Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deacetilasi oin combinazione con l’inibitore della sintesi del glutatione butiomina sulfoximina nel risvegliare dalla quiescienzale cellule che integrano HIV-1
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http://www.retrovirology.com/content/6/1/52
Retrovirology. 2009 Jun 2;6(1):52
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Benzanthrone induced immunotoxicity via oxidative stressPrachi Tewari
The document summarizes a study on the immunotoxic effects of benzanthrone (BA) in mice. The key findings are:
1) BA exposed mice exhibited signs of systemic inflammation like enhanced delayed type hypersensitivity response and myeloperoxidase activity. Histopathological examination showed hyperplastic and dysplastic changes in spleen and lung tissues.
2) Exposure to BA led to oxidative stress, upregulation of inflammatory markers iNOS and COX-2, and DNA damage in spleen tissues.
3) Inflammatory and regulatory cytokine levels like IL-17, TNF-α, IFN-γ, IL-1, IL-10 and IL-4 were significantly increased in serum and spleen tissues.
Aluminium hydroxide, Aluminium phosphate and calcium phosphate are used as adjuvant in (TT) vaccine. In this review mechanism, potency, benefits and limitations of alum adjuvant have been discussed.
This document provides an introduction to the fifth edition of the manual "Recognition and Management of Pesticide Poisonings". The manual aims to provide health professionals with information on currently used pesticides and their health hazards, as well as recommendations for managing pesticide poisonings. Pesticide poisoning remains underdiagnosed, so the manual seeks to improve education of healthcare providers in this area. Key principles of pesticide poisoning management discussed include airway protection, gastric emptying procedures, use of activated charcoal and other decontamination methods, and hemodialysis or hemoperfusion for severe poisonings. Common pesticide exposures associated with poisonings are also summarized based on national surveillance data.
Invited lectures, presentations and publicationsOlga Pulido
This document lists invited lectures, publications, and research presentations by the author from 2000 to the present. It focuses on topics related to toxicology pathology, including harmful algal blooms, celiac disease, neurotoxicology, food allergens and excitotoxins, marine biotoxins, and the role of pathology in regulatory toxicology. Many of the presentations and publications were invited works in international forums on topics pertaining to the health effects of environmental and food toxins.
This document summarizes findings from studies on acute pesticide poisonings. It identifies the following key points:
1) Cholinesterase-inhibiting pesticides (organophosphates and carbamates) were the most common causes of severe acute poisonings and deaths. Commonly implicated pesticides include aldicarb, methyl parathion, and carbofuran.
2) Paraquat and endosulfan have also been frequent causes of severe acute poisonings, including fatal cases.
3) The use of pesticide mixtures is related to higher incidence of poisonings. Developing countries commonly have unsafe pesticide application practices like using backpacks without protective equipment.
4
This document describes the design, synthesis, and evaluation of novel antimicrobial dipeptidomimetic compounds. A library of linear and branched dipeptidomimetics was created by modifying spermine with tryptophan residues at different positions and with different N-terminal tags. Eight compounds showed good antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis. Two lead compounds were nonhemolytic, rapidly bactericidal against MRSA, and did not induce resistance after multiple passages. These compounds were also effective against MRSA biofilms by inhibiting formation and reducing viability of mature biofilms. The membrane interactions and lower
Antimicrobial Sensitivity Pattern of Pseudomonas fluorescens after Biofield T...Mahendra Kumar Trivedi
Objective of this study was to investigate the effect of biofield treatment on antimicrobial sensitivity patternof P. fluorescens. P. fluorescens cells were procured from MicroBioLogics in sealed packs bearing the AmericanType Culture Collection (ATCC 49838) number.
Toxicology is the branch of science that deals with nature, effects, and detection of poison. The degree to which a substance can harm an organism is called toxicity. The types of toxicity depending upon the time of exposure of the toxicant have been described.
Benzanthrone induced immunotoxicity via oxidative stressPrachi Tewari
The document summarizes a study on the immunotoxic effects of benzanthrone (BA) in mice. The key findings are:
1) BA exposed mice exhibited signs of systemic inflammation like enhanced delayed type hypersensitivity response and myeloperoxidase activity. Histopathological examination showed hyperplastic and dysplastic changes in spleen and lung tissues.
2) Exposure to BA led to oxidative stress, upregulation of inflammatory markers iNOS and COX-2, and DNA damage in spleen tissues.
3) Inflammatory and regulatory cytokine levels like IL-17, TNF-α, IFN-γ, IL-1, IL-10 and IL-4 were significantly increased in serum and spleen tissues.
Aluminium hydroxide, Aluminium phosphate and calcium phosphate are used as adjuvant in (TT) vaccine. In this review mechanism, potency, benefits and limitations of alum adjuvant have been discussed.
This document provides an introduction to the fifth edition of the manual "Recognition and Management of Pesticide Poisonings". The manual aims to provide health professionals with information on currently used pesticides and their health hazards, as well as recommendations for managing pesticide poisonings. Pesticide poisoning remains underdiagnosed, so the manual seeks to improve education of healthcare providers in this area. Key principles of pesticide poisoning management discussed include airway protection, gastric emptying procedures, use of activated charcoal and other decontamination methods, and hemodialysis or hemoperfusion for severe poisonings. Common pesticide exposures associated with poisonings are also summarized based on national surveillance data.
Invited lectures, presentations and publicationsOlga Pulido
This document lists invited lectures, publications, and research presentations by the author from 2000 to the present. It focuses on topics related to toxicology pathology, including harmful algal blooms, celiac disease, neurotoxicology, food allergens and excitotoxins, marine biotoxins, and the role of pathology in regulatory toxicology. Many of the presentations and publications were invited works in international forums on topics pertaining to the health effects of environmental and food toxins.
This document summarizes findings from studies on acute pesticide poisonings. It identifies the following key points:
1) Cholinesterase-inhibiting pesticides (organophosphates and carbamates) were the most common causes of severe acute poisonings and deaths. Commonly implicated pesticides include aldicarb, methyl parathion, and carbofuran.
2) Paraquat and endosulfan have also been frequent causes of severe acute poisonings, including fatal cases.
3) The use of pesticide mixtures is related to higher incidence of poisonings. Developing countries commonly have unsafe pesticide application practices like using backpacks without protective equipment.
4
This document describes the design, synthesis, and evaluation of novel antimicrobial dipeptidomimetic compounds. A library of linear and branched dipeptidomimetics was created by modifying spermine with tryptophan residues at different positions and with different N-terminal tags. Eight compounds showed good antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis. Two lead compounds were nonhemolytic, rapidly bactericidal against MRSA, and did not induce resistance after multiple passages. These compounds were also effective against MRSA biofilms by inhibiting formation and reducing viability of mature biofilms. The membrane interactions and lower
Antimicrobial Sensitivity Pattern of Pseudomonas fluorescens after Biofield T...Mahendra Kumar Trivedi
Objective of this study was to investigate the effect of biofield treatment on antimicrobial sensitivity patternof P. fluorescens. P. fluorescens cells were procured from MicroBioLogics in sealed packs bearing the AmericanType Culture Collection (ATCC 49838) number.
Toxicology is the branch of science that deals with nature, effects, and detection of poison. The degree to which a substance can harm an organism is called toxicity. The types of toxicity depending upon the time of exposure of the toxicant have been described.
Hydroxychloroquine was found to be more potent than chloroquine at inhibiting SARS-CoV-2 in vitro. Based on physiologically-based pharmacokinetic models, a dosing regimen of hydroxychloroquine sulfate 400 mg twice daily for one day, followed by 200 mg twice daily for four more days is recommended for treating SARS-CoV-2 infection. This dosing regimen achieved concentrations in lung fluid three times higher than a chloroquine regimen used in previous studies.
INTRODUCTION
Toxicology is the science of the poisons. It also studies the nature, effects, detection, assessment and treatment of their effects on biological material.
Toxicology is a multidisciplinary science. The ultimate objective of the combined research is to determine how an organism is affected by exposure to an agent.
This includes an understanding of:
How the agent moves and interact with living cells and tissues of the organism;
What parts of the organism are affected by its presence and health outcomes of this exposure.
Evaluation of the toxicity of substances whose biological effects may not have been well characterized.
The influence of chemical toxicity is mainly
determined by the dosage, duration of exposure,
route of exposure, species, age, sex, and environment.
The goal of toxicology is to contribute to the
general knowledge and harmful actions of
chemical substances.
2. to study their mechanisms of action,
3. and to estimate their possible risks to humans
HISTORY
Dioscorides, a Greek physician in the court of the Roman emperor Nero, made the first attempt to classify plants according to their toxic and therapeutic effect. Poisonous plants and animals were recognized and their extracts used for hunting or in warfare.
In 1500 BC people used hemlock, opium, arrow poisons, and certain metals to poison enemies or for state executions.
Theophrastus Phillipus Auroleus Bombastus von Hohenheim (1493–1541) (also referred to as Paracelsus, a Roman physician from the first century) is considered "the father" of toxicology.
He stated that "All things are poisonous and nothing is without poison; only the dose makes a thing not poisonous.“
Mathieu Orfila (1813) is considered the modern father of toxicology.
In 1850, Jean Stas became the first person to successfully isolate plant poisons from human tissue.
Hippolyte Visart de Bocarmé used nicotine to kill his brother-in-law. He extracted nicotine from tobacco leaves.
The 20th and 21st Centuries have marked by great advancements in the level of understanding of toxicology. DNA and various biochemicals that maintain body functions have been discovered. Our level of knowledge of toxic effects on organs and cells has expanded to the molecular level.
This document provides an overview of toxicology and environmental toxicology. It discusses how environmental toxicology examines the effects of chemicals released into the environment on human health, other animals, and ecosystems. It defines key terms like toxicant, pollutant, and persistence. It also describes how synthetic chemicals are now ubiquitous in the environment, how they can accumulate and concentrate in water and air, mimic hormones, and persist for long periods.
An Impact of Biofield Treatment: Antimycobacterial Susceptibility Potential U...albertdivis
The aim was to evaluate the impact of biofield treatment modality on mycobacterial strains in relation to antimycobacterials susceptibility. Mycobacterial sensitivity was analysed using 12 B BACTEC vials on the BACTEC 460 TB machine in 39 lab isolates (sputum samples) from stored stock cultures.
This document discusses research on the effects of omalizumab (anti-IgE therapy) treatment in patients with severe persistent asthma over 4 years. It lists 15 publications by the author on outcomes related to omalizumab therapy, including effects on oxidative stress markers, cytokines, quality of life, and side effects. The author has studied how omalizumab impacts factors involved in coagulation, fibrinolysis, angiogenesis and inflammation.
This document summarizes research on a class of compounds called thiazolides and their potential as antiviral agents, specifically against hepatitis B virus (HBV). Key points:
1. Thiazolides show promise as novel antiviral agents that could help treat HBV infections by acting through a non-resistance inducing mechanism. Nitazoxanide is a broad-spectrum thiazolide currently used as an antiparasitic drug.
2. The study synthesized and tested a wide range of thiazolide analogs for anti-HBV activity. Compound 3 showed potent and selective inhibition of HBV replication with low toxicity.
3. Structure-activity relationship analysis found good correlation
Hepatoprotective and antioxidant effects of Azolla microphylla based gold nan...Nanomedicine Journal (NMJ)
Abstract
Objective(s):
Our present study sought to evaluate hepatoprotective and antioxidant effects of methanol extract of Azolla microphylla phytochemically synthesized gold nanoparticles (GNaP) in acetaminophen (APAP) - induced hepatotoxicity of fresh water common carp fish.
Materials and Methods:
GNaP were prepared by green synthesis method using methanol extract of Azolla microphylla. Twenty four fishes weighing 146 ± 2.5 g were used in this experiment and these were divided into four experimental groups, each comprising 6 fishes. Group 1 served as control. Group 2 fishes were exposed to APAP (500 mg/kg) for 24 h. Groups 3 and 4 fishes were exposed to APAP (500 mg/kg) + GNaP (2.5 mg/kg) and GNaP (2.5 mg/kg) for 24 h, respectively. The hepatoprotective and antioxidant potentials were assessed by measuring liver damage, biochemical parameters, ions status, and histological alterations.
Results:
APAP exposed fish showed significant elevated levels of metabolic enzymes (LDH, G6PDH and MDH), hepatotoxic markers (GPT, GOT and ALP), reduced hepatic glycogen, lipids, protein, albumin, globulin, increased levels of bilirubin, creatinine, and oxidative stress markers (TBRAS, LHP and protein carbonyl), altered the tissue enzymes (SOD, CAT, GSH-Px and GST) non-enzyme (GSH), cellular sulfhydryl (T-SH, P-SH and NP-SH) levels, reduced hepatic ions (Ca2+, Na+ and K+), and abnormal liver histology. It was observe that GNaP has reversal effects on the levels of above mentioned parameters in APAP hepatotoxicity.
Conclusion:
Azolla microphylla phytochemically synthesized GNaP protects liver against oxidative damage and tissue damaging enzyme activities and could be used as an effective protector against acetaminophen-induced hepatic damage in fresh water common carp fish.
Limitations in the screening of potentially anti-cryptosporidial agents using...UniversitasGadjahMada
The emergence of cryptosporidiosis, a zoonotic disease of the gastrointestinal and respiratory tract caused by Cryptosporidium Tyzzer, 1907, triggered numerous screening studies of various compounds for potential anti-cryptosporidial activity, the majority of which proved ineffective. Extracts of Indonesian plants, Piper betle and Diospyros sumatrana, were tested for potential anticryptosporidial activity using Mastomys coucha (Smith), experimentally inoculated with Cryptosporidium proliferans Kváč, Havrdová, Hlásková, Daňková, Kanděra, Ježková, Vítovec, Sak, Ortega, Xiao, Modrý, Chelladurai, Prantlová et McEvoy, 2016. None of the plant extracts tested showed significant activity against cryptosporidia; however, the results indicate that the following issues should be addressed in similar experimental studies. The monitoring of oocyst shedding during the entire experimental trial, supplemented with histological examination of affected gastric tissue at the time of treatment termination, revealed that similar studies are generally unreliable if evaluations of drug efficacy are based exclusively on oocyst shedding. Moreover, the reduction of oocyst shedding did not guarantee the eradication of cryptosporidia in treated individuals. For treatment trials performed on experimentally inoculated laboratory rodents, only animals in the advanced phase of cryptosporidiosis should be used for the correct interpretation of pathological alterations observed in affected tissue. All the solvents used (methanol, methanol-tetrahydrofuran and dimethylsulfoxid) were shown to be suitable for these studies, i.e. they did not exhibit negative effects on the subjects. The halofuginone lactate, routinely administered in intestinal cryptosporidiosis in calves, was shown to be ineffective against gastric cryptosporidiosis in mice caused by C. proliferans. In contrast, the control application of extract Arabidopsis thaliana, from which we had expected a neutral effect, turned out to have some positive impact on affected gastric tissue.
Biochemical Characteristics of Staphylococcus aureusdeeptimishra10
The specific biochemicals showed some changes against S. aureus after biofiel d treatment. In this study, overall 37.93% biochemical reactions were altered in tested twenty nine biochemicals with respect to control after biofield treatment.
The document summarizes an experiment using an ELISA test with recombinant NcSAG1 to detect antibodies for Neospora caninum in canine serum samples. Key points:
- The indirect ELISA method was used to test 12 canine serum samples for N. caninum antibodies. This method has advantages like increased sensitivity but requires an extra incubation step.
- OD values indicated samples 1, 4, and 3 had the highest antibody levels while samples 9, 6, and 2 had the lowest.
- Based on the OD values, samples 1, 3, 4, 5, 7, 8, 10, 11, and 12 tested positive for N. caninum antibodies while 2,
Toxicology deals with the study of the harmful effects of chemicals on living beings. This branch of science has been equally recognised in medical as well as scientific field
Assessment of Antibiogram of Multidrug-Resistant Isolates of Enterobacter aer...wilhelm mendel
Enterobacter aerogenes (E. aerogenes) has been reported as the versatile opportunistic pathogen associated with the hospital infections worldwide. The aim of the study was to determine the impact of Mr. Trivedi’s biofield energy treatment on multidrug resistant clinical lab isolates (LSs) of E. aerogenes. The MDR isolates of E. aerogenes (i.e., LS 45 and LS 54) were divided into two groups, i.e., control and treated. Samples were analyzed for antimicrobial susceptibility pattern, minimum inhibitory concentration (MIC), biochemical study, and biotype number using MicroScan Walk-Away® system, on day 10 after the biofield treatment. The antimicrobial sensitivity assay showed 14.28% alteration out of twenty eight tested antimicrobials with respect to the control. The cefotetan sensitivity changed from intermediate (I) to inducible β-lactamase (IB), while piperacillin/tazobactam changed from resistant to IB in the treated LS 45. Improved sensitivity was reported in tetracycline, i.e., from I to susceptible (S) in LS 45, while chloramphenicol and tetracycline sensitivity changed from R to I in treated LS 54. Four-fold decrease in MIC value was reported in piperacillin/tazobactam, and two-fold decrease in cefotetan and tetracycline in the biofield treated LS 45 as compared to the control. MIC results showed an overall decreased MIC values in 12.50% tested antimicrobials such as chloramphenicol (16 μg/mL) and tetracycline (8 μg/mL) in LS 54. The biochemical study showed an overall 45.45% negative reaction in the tested biochemical in both the treated isolates as compared to the control. A change in biotype number was reported in MDR isolates (LS 45 and LS 54), while in LS 54, altered biotype number, i.e., 0406 0374 as compared to the control (7770 4376), with identification of the new species as Stenotrophomonas maltophilia with brown color as special characteristic. The study findings suggest that Mr. Trivedi’s biofield energy treatment on clinical MDR isolates of E. aerogenes has the significant effect on altering the sensitivity of antimicrobials, decreasing the MIC values, changed biochemical reactions, and biotype number.
Environmental toxicity Dr prerok regmi 15th May 2018Dr. Prerok regmi
This document discusses environmental toxicity and pollution. It defines key terms like environment, ecosystem, toxicity, toxins, and pollutants. It describes different types of pollution like air, water, soil, and radiation pollution. It discusses how pollution can lead to environmental toxicity and disease. Methods to assess and manage risks of environmental incidents are outlined. Historical examples from ancient texts describe how kings would check for poison in water, food, air and surroundings when entering enemy territories. Various techniques to detect and remove toxins from air and water are also mentioned from ancient texts.
Arif Jamal Siddiqui is currently a postdoctoral research associate at Texas Tech University Health Science Center in Lubbock, Texas. He received his PhD in biological sciences from the Academy of Scientific and Innovative Research in New Delhi, India. His research focuses on immunology, molecular cell biology, and drug discovery for diseases like malaria and schistosomiasis. Currently, he is working on developing vaccines for schistosomiasis using the Sm-P80 vaccine in baboons.
1) Nanorobots could potentially be used to treat AIDS by recognizing and converting HIV-infected white blood cells back to their original form, maintaining a constant level of immune cells and allowing the patient to defend against diseases.
2) The nanorobot would use a DNA sensor to identify HIV-infected cells and an RNA converter to change the cell's RNA and reverse the HIV infection. It would be powered by metabolizing glucose and oxygen or external acoustic power.
3) Key challenges in using nanorobots for this approach include their size needing to be small enough to avoid blocking blood flow while still performing tasks, using biocompatible materials like diamond or carbon that don't trigger an immune response, and
The biotechnology revolution - Background informationXplore Health
This guide provides background information on the current techniques used in biotechnology as well as information on the the ethical, legal and social aspects associated with biotechnology.
This document provides an introduction to toxicology and multiple choice questions (MCQs) related to the field. It discusses key topics like dose-response relationships, routes of exposure, biotransformation, bioaccumulation, targets of chemicals, acute vs chronic toxicity, and phases of biotransformation. The document is intended to help students and general audiences improve their knowledge of toxicology through practicing MCQs. It includes 20 MCQs in the first set, with answer keys and brief explanations provided for each.
This document discusses using tannins extracted from Guazuma ulmifolia to inhibit the HIV virus. It aims to identify the molecular weight of tannin that most effectively inhibits the HIV reverse transcriptase with the fewest toxic side effects. The justification is that current anti-HIV drugs can have significant side effects and new treatments are needed. Tannins may offer an alternative as studies have shown some can inhibit HIV replication, but their specific mechanisms and toxicities require further investigation.
The document discusses using tannins extracted from Guazuma ulmifolia to inhibit the HIV reverse transcriptase. It aims to identify the molecular weight of tannin that most effectively inhibits HIV replication with lowest toxicity. The justification is the need for new anti-HIV drugs due to virus persistence and resistance to current treatments, which can cause side effects. Some studies found tannins show inhibitory activity against HIV replication.
Hydroxychloroquine was found to be more potent than chloroquine at inhibiting SARS-CoV-2 in vitro. Based on physiologically-based pharmacokinetic models, a dosing regimen of hydroxychloroquine sulfate 400 mg twice daily for one day, followed by 200 mg twice daily for four more days is recommended for treating SARS-CoV-2 infection. This dosing regimen achieved concentrations in lung fluid three times higher than a chloroquine regimen used in previous studies.
INTRODUCTION
Toxicology is the science of the poisons. It also studies the nature, effects, detection, assessment and treatment of their effects on biological material.
Toxicology is a multidisciplinary science. The ultimate objective of the combined research is to determine how an organism is affected by exposure to an agent.
This includes an understanding of:
How the agent moves and interact with living cells and tissues of the organism;
What parts of the organism are affected by its presence and health outcomes of this exposure.
Evaluation of the toxicity of substances whose biological effects may not have been well characterized.
The influence of chemical toxicity is mainly
determined by the dosage, duration of exposure,
route of exposure, species, age, sex, and environment.
The goal of toxicology is to contribute to the
general knowledge and harmful actions of
chemical substances.
2. to study their mechanisms of action,
3. and to estimate their possible risks to humans
HISTORY
Dioscorides, a Greek physician in the court of the Roman emperor Nero, made the first attempt to classify plants according to their toxic and therapeutic effect. Poisonous plants and animals were recognized and their extracts used for hunting or in warfare.
In 1500 BC people used hemlock, opium, arrow poisons, and certain metals to poison enemies or for state executions.
Theophrastus Phillipus Auroleus Bombastus von Hohenheim (1493–1541) (also referred to as Paracelsus, a Roman physician from the first century) is considered "the father" of toxicology.
He stated that "All things are poisonous and nothing is without poison; only the dose makes a thing not poisonous.“
Mathieu Orfila (1813) is considered the modern father of toxicology.
In 1850, Jean Stas became the first person to successfully isolate plant poisons from human tissue.
Hippolyte Visart de Bocarmé used nicotine to kill his brother-in-law. He extracted nicotine from tobacco leaves.
The 20th and 21st Centuries have marked by great advancements in the level of understanding of toxicology. DNA and various biochemicals that maintain body functions have been discovered. Our level of knowledge of toxic effects on organs and cells has expanded to the molecular level.
This document provides an overview of toxicology and environmental toxicology. It discusses how environmental toxicology examines the effects of chemicals released into the environment on human health, other animals, and ecosystems. It defines key terms like toxicant, pollutant, and persistence. It also describes how synthetic chemicals are now ubiquitous in the environment, how they can accumulate and concentrate in water and air, mimic hormones, and persist for long periods.
An Impact of Biofield Treatment: Antimycobacterial Susceptibility Potential U...albertdivis
The aim was to evaluate the impact of biofield treatment modality on mycobacterial strains in relation to antimycobacterials susceptibility. Mycobacterial sensitivity was analysed using 12 B BACTEC vials on the BACTEC 460 TB machine in 39 lab isolates (sputum samples) from stored stock cultures.
This document discusses research on the effects of omalizumab (anti-IgE therapy) treatment in patients with severe persistent asthma over 4 years. It lists 15 publications by the author on outcomes related to omalizumab therapy, including effects on oxidative stress markers, cytokines, quality of life, and side effects. The author has studied how omalizumab impacts factors involved in coagulation, fibrinolysis, angiogenesis and inflammation.
This document summarizes research on a class of compounds called thiazolides and their potential as antiviral agents, specifically against hepatitis B virus (HBV). Key points:
1. Thiazolides show promise as novel antiviral agents that could help treat HBV infections by acting through a non-resistance inducing mechanism. Nitazoxanide is a broad-spectrum thiazolide currently used as an antiparasitic drug.
2. The study synthesized and tested a wide range of thiazolide analogs for anti-HBV activity. Compound 3 showed potent and selective inhibition of HBV replication with low toxicity.
3. Structure-activity relationship analysis found good correlation
Hepatoprotective and antioxidant effects of Azolla microphylla based gold nan...Nanomedicine Journal (NMJ)
Abstract
Objective(s):
Our present study sought to evaluate hepatoprotective and antioxidant effects of methanol extract of Azolla microphylla phytochemically synthesized gold nanoparticles (GNaP) in acetaminophen (APAP) - induced hepatotoxicity of fresh water common carp fish.
Materials and Methods:
GNaP were prepared by green synthesis method using methanol extract of Azolla microphylla. Twenty four fishes weighing 146 ± 2.5 g were used in this experiment and these were divided into four experimental groups, each comprising 6 fishes. Group 1 served as control. Group 2 fishes were exposed to APAP (500 mg/kg) for 24 h. Groups 3 and 4 fishes were exposed to APAP (500 mg/kg) + GNaP (2.5 mg/kg) and GNaP (2.5 mg/kg) for 24 h, respectively. The hepatoprotective and antioxidant potentials were assessed by measuring liver damage, biochemical parameters, ions status, and histological alterations.
Results:
APAP exposed fish showed significant elevated levels of metabolic enzymes (LDH, G6PDH and MDH), hepatotoxic markers (GPT, GOT and ALP), reduced hepatic glycogen, lipids, protein, albumin, globulin, increased levels of bilirubin, creatinine, and oxidative stress markers (TBRAS, LHP and protein carbonyl), altered the tissue enzymes (SOD, CAT, GSH-Px and GST) non-enzyme (GSH), cellular sulfhydryl (T-SH, P-SH and NP-SH) levels, reduced hepatic ions (Ca2+, Na+ and K+), and abnormal liver histology. It was observe that GNaP has reversal effects on the levels of above mentioned parameters in APAP hepatotoxicity.
Conclusion:
Azolla microphylla phytochemically synthesized GNaP protects liver against oxidative damage and tissue damaging enzyme activities and could be used as an effective protector against acetaminophen-induced hepatic damage in fresh water common carp fish.
Limitations in the screening of potentially anti-cryptosporidial agents using...UniversitasGadjahMada
The emergence of cryptosporidiosis, a zoonotic disease of the gastrointestinal and respiratory tract caused by Cryptosporidium Tyzzer, 1907, triggered numerous screening studies of various compounds for potential anti-cryptosporidial activity, the majority of which proved ineffective. Extracts of Indonesian plants, Piper betle and Diospyros sumatrana, were tested for potential anticryptosporidial activity using Mastomys coucha (Smith), experimentally inoculated with Cryptosporidium proliferans Kváč, Havrdová, Hlásková, Daňková, Kanděra, Ježková, Vítovec, Sak, Ortega, Xiao, Modrý, Chelladurai, Prantlová et McEvoy, 2016. None of the plant extracts tested showed significant activity against cryptosporidia; however, the results indicate that the following issues should be addressed in similar experimental studies. The monitoring of oocyst shedding during the entire experimental trial, supplemented with histological examination of affected gastric tissue at the time of treatment termination, revealed that similar studies are generally unreliable if evaluations of drug efficacy are based exclusively on oocyst shedding. Moreover, the reduction of oocyst shedding did not guarantee the eradication of cryptosporidia in treated individuals. For treatment trials performed on experimentally inoculated laboratory rodents, only animals in the advanced phase of cryptosporidiosis should be used for the correct interpretation of pathological alterations observed in affected tissue. All the solvents used (methanol, methanol-tetrahydrofuran and dimethylsulfoxid) were shown to be suitable for these studies, i.e. they did not exhibit negative effects on the subjects. The halofuginone lactate, routinely administered in intestinal cryptosporidiosis in calves, was shown to be ineffective against gastric cryptosporidiosis in mice caused by C. proliferans. In contrast, the control application of extract Arabidopsis thaliana, from which we had expected a neutral effect, turned out to have some positive impact on affected gastric tissue.
Biochemical Characteristics of Staphylococcus aureusdeeptimishra10
The specific biochemicals showed some changes against S. aureus after biofiel d treatment. In this study, overall 37.93% biochemical reactions were altered in tested twenty nine biochemicals with respect to control after biofield treatment.
The document summarizes an experiment using an ELISA test with recombinant NcSAG1 to detect antibodies for Neospora caninum in canine serum samples. Key points:
- The indirect ELISA method was used to test 12 canine serum samples for N. caninum antibodies. This method has advantages like increased sensitivity but requires an extra incubation step.
- OD values indicated samples 1, 4, and 3 had the highest antibody levels while samples 9, 6, and 2 had the lowest.
- Based on the OD values, samples 1, 3, 4, 5, 7, 8, 10, 11, and 12 tested positive for N. caninum antibodies while 2,
Toxicology deals with the study of the harmful effects of chemicals on living beings. This branch of science has been equally recognised in medical as well as scientific field
Assessment of Antibiogram of Multidrug-Resistant Isolates of Enterobacter aer...wilhelm mendel
Enterobacter aerogenes (E. aerogenes) has been reported as the versatile opportunistic pathogen associated with the hospital infections worldwide. The aim of the study was to determine the impact of Mr. Trivedi’s biofield energy treatment on multidrug resistant clinical lab isolates (LSs) of E. aerogenes. The MDR isolates of E. aerogenes (i.e., LS 45 and LS 54) were divided into two groups, i.e., control and treated. Samples were analyzed for antimicrobial susceptibility pattern, minimum inhibitory concentration (MIC), biochemical study, and biotype number using MicroScan Walk-Away® system, on day 10 after the biofield treatment. The antimicrobial sensitivity assay showed 14.28% alteration out of twenty eight tested antimicrobials with respect to the control. The cefotetan sensitivity changed from intermediate (I) to inducible β-lactamase (IB), while piperacillin/tazobactam changed from resistant to IB in the treated LS 45. Improved sensitivity was reported in tetracycline, i.e., from I to susceptible (S) in LS 45, while chloramphenicol and tetracycline sensitivity changed from R to I in treated LS 54. Four-fold decrease in MIC value was reported in piperacillin/tazobactam, and two-fold decrease in cefotetan and tetracycline in the biofield treated LS 45 as compared to the control. MIC results showed an overall decreased MIC values in 12.50% tested antimicrobials such as chloramphenicol (16 μg/mL) and tetracycline (8 μg/mL) in LS 54. The biochemical study showed an overall 45.45% negative reaction in the tested biochemical in both the treated isolates as compared to the control. A change in biotype number was reported in MDR isolates (LS 45 and LS 54), while in LS 54, altered biotype number, i.e., 0406 0374 as compared to the control (7770 4376), with identification of the new species as Stenotrophomonas maltophilia with brown color as special characteristic. The study findings suggest that Mr. Trivedi’s biofield energy treatment on clinical MDR isolates of E. aerogenes has the significant effect on altering the sensitivity of antimicrobials, decreasing the MIC values, changed biochemical reactions, and biotype number.
Environmental toxicity Dr prerok regmi 15th May 2018Dr. Prerok regmi
This document discusses environmental toxicity and pollution. It defines key terms like environment, ecosystem, toxicity, toxins, and pollutants. It describes different types of pollution like air, water, soil, and radiation pollution. It discusses how pollution can lead to environmental toxicity and disease. Methods to assess and manage risks of environmental incidents are outlined. Historical examples from ancient texts describe how kings would check for poison in water, food, air and surroundings when entering enemy territories. Various techniques to detect and remove toxins from air and water are also mentioned from ancient texts.
Arif Jamal Siddiqui is currently a postdoctoral research associate at Texas Tech University Health Science Center in Lubbock, Texas. He received his PhD in biological sciences from the Academy of Scientific and Innovative Research in New Delhi, India. His research focuses on immunology, molecular cell biology, and drug discovery for diseases like malaria and schistosomiasis. Currently, he is working on developing vaccines for schistosomiasis using the Sm-P80 vaccine in baboons.
Similar to Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deacetilasi oin combinazione con l’inibitore della sintesi del glutatione butiomina sulfoximina nel risvegliare dalla quiescienzale cellule che integrano HIV-1
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The biotechnology revolution - Background informationXplore Health
This guide provides background information on the current techniques used in biotechnology as well as information on the the ethical, legal and social aspects associated with biotechnology.
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This document discusses using tannins extracted from Guazuma ulmifolia to inhibit the HIV virus. It aims to identify the molecular weight of tannin that most effectively inhibits the HIV reverse transcriptase with the fewest toxic side effects. The justification is that current anti-HIV drugs can have significant side effects and new treatments are needed. Tannins may offer an alternative as studies have shown some can inhibit HIV replication, but their specific mechanisms and toxicities require further investigation.
The document discusses using tannins extracted from Guazuma ulmifolia to inhibit the HIV reverse transcriptase. It aims to identify the molecular weight of tannin that most effectively inhibits HIV replication with lowest toxicity. The justification is the need for new anti-HIV drugs due to virus persistence and resistance to current treatments, which can cause side effects. Some studies found tannins show inhibitory activity against HIV replication.
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Basic definition and types of toxicology (general, mechanistic, regulatory and descriptive), Regulatory guidelines for conducting toxicity studies OECD, ICH, EPA and Schedule Y OECD principles of Good laboratory practice (GLP)
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This document provides a summary of a student's research project on using personalised learning strategies to overcome difficulties in understanding biology topics related to pathogens and antibiotic resistance. The research project involved examining educational placement, background, aims and objectives. Effectiveness of strategies was assessed through references and an appendix providing details on case studies and educational introduction, biological introduction on pathogens and antibiotic resistance, as well as further learning sections on HIV and Ebola.
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This chapter discusses environmental health and toxicology. It introduces key concepts like what environmental health is, emerging infectious diseases, toxins and their effects on health, and how toxicity is measured. It also examines factors that influence the movement and concentration of toxins in ecosystems and organisms, and mechanisms that minimize toxic effects. Risk assessment and establishing public policy to address environmental health issues are also covered.
Pharmacogenetics and antibiotic drugs.pptxGunjitSetia1
Antibiotics have revolutionized modern medicine, saving countless lives by combatting bacterial infections.
However, the emergence of antibiotic-resistant bacteria presents a formidable challenge to global health.
Pharmacogenetics focuses on the interplay between an individual's genetic makeup and their response to drugs.
This presentation delves into the intriguing realm of pharmacogenetics within the context of antibiotic therapy, aiming to shed light on how genetic variations can influence antibiotic effectiveness and how this knowledge can be harnessed to develop more precise, personalized treatment strategies.
The Role Of Cytokines On Immune PrivilegeKaty Allen
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- Experiments on mice found that chronic early-life stress impaired microglial function and rewired the brain's stress response pathways, causing depression-like behaviors in adulthood. Treating the stress hormone CRH reversed these effects.
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The document discusses several methods for controlling infectious diseases, including preventing transmission, modifying the environment, behavioral changes, immunization, and using antimicrobial drugs and vaccines. It provides details on the different types of vaccines, how they work, and new approaches like DNA vaccines and monoclonal antibodies. The roles of organizations like the WHO and CDC in monitoring, controlling and preventing the spread of diseases globally are also summarized.
The document discusses using tannins extracted from the Guazuma ulmifolia plant to inhibit the reverse transcriptase of the HIV virus. The study aims to identify the most effective tannin for inhibiting viral replication with the lowest toxicity risk. Specifically, it seeks to determine the molecular weight of tannin that most strongly inhibits the reverse transcriptase with fewest side effects. The justification is the need for new HIV treatment options given virus persistence and drug resistance, as well as high rates of side effects from current antiretroviral drugs.
1. The document discusses approaches to evaluating the toxicity of industrial chemicals in a humane manner. It examines using laboratory animals versus alternative in vitro methods.
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3. Society demands high certainty in toxicity assessments to minimize risk to humans. Toxicologists must be cautious not to reduce predictive quality by replacing animal tests prematurely with alternatives that have not been fully validated.
Toxicology is the study of poisons and their effects. There are several branches and types of toxicology. Descriptive toxicology focuses on toxicity testing through hazard identification, dose-response assessment, exposure assessment, and risk characterization. This involves in vitro, in vivo, and in silico testing to evaluate toxic doses, safe exposure levels, and set regulatory standards to protect public health. Mechanistic toxicology studies how toxins interact with living organisms on a molecular level. Regulatory toxicology supports rule making and compliance through standardized testing protocols.
This document discusses experimental therapy using intravenous administration of sodium hypochlorite solution to treat antibiotic-resistant bacteria and other severe viral infections. Sodium hypochlorite generates reactive oxygen species that can destroy bacteria and viruses. The therapy has been approved in Russia and involves intravenous infusions of diluted sodium hypochlorite at doses of 30-300 mg/L daily for 10-20 days. Preliminary studies show the method is effective against multidrug-resistant bacteria and potential for treating diseases like Ebola and hepatitis.
A brief description to antibiotic uses in chemistry.It includes almost every thing related to antibiotic chemistry
Similar to Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deacetilasi oin combinazione con l’inibitore della sintesi del glutatione butiomina sulfoximina nel risvegliare dalla quiescienzale cellule che integrano HIV-1 (20)
Il consumo di antiossidanti e di integratori è un fenomeno crescente nella nostra società. Negli Stati Uniti circa il 50% degli adulti assume integratori, con una spesa di circa 17,5 miliardi di euro/anno.
Di fronte a un fenomeno così imponente ci si è chiesti quale fosse il reale impatto di tali consumi sulla salute.
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I risultati sono sconfortanti e sconcertanti: se è vero che l’assunzione di selenio sembra blandamente protettiva, la vitamina E sembra associata a un incremento del 17% del rischio di carcinoma della prostata.
Questo studio pone una grossa ipoteca sull’abitudine alla supplementazione, un’ipoteca che probabilmente va ben oltre l’oggetto dello studio.
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L’insegnamento che dovremmo trarne è che i consumatori dovrebbero essere scettici sulle promesse riguardanti la salute di prodotti “da banco” che non mostrino forti evidenze da studi clinici… peccato che -per definizione- questo tipo di prodotti sia venduto come integratore alimentare e quindi non ci siano quasi mai studi specifici, al più richiami a proprietà dei principi attivi in essi contenuti, solitamente incoerenti con i dosaggi finali e la prospettiva di assunzione vita natural durante di questi prodotti…
This one sentence document appears to be testing the ability to download something, but provides no other context or information. It is unclear what is specifically being tested or evaluated based on the download.
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Articolo di “Più Salute”.
Il caso è stato sollevato dall’Nps, l’associazione di persone sieropositive, che ha segnalato all’Autorità garante della privacy che “uno studio dentistico raccoglieva informazioni sull'Hiv mediante la distribuzione di un questionario al momento dell'accettazione dei pazienti”, una raccolta generalizzata e ingiustificata di informazioni delicatissime.
Un dato che non può essere richiesto quando il paziente arriva in studio per la prima volta, ma solo in un secondo momento e solo se può determinare la scelta della terapia.
Ricerca italiana: al via i test sull’uomo del vaccino anti-HIVmabasta
Articolo di “Più Salute” sulle prospettive di un vaccino per l’HIV, con intervista al Prof. Arnaldo Caruso, Docente di Microbiologia dell’Università di Brescia.
Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deaceti...mabasta
Questo è il file con il quale l’articolo è stato proposto alla rivista. Viene direttamente dal sito della rivista, ed è accessibile sotto la licenza “open access”, perciò non ci sono problemi legali.
http://www.retrovirology.com/content/6/1/52
Retrovirology. 2009 Jun 2;6(1):52
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Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deaceti...mabasta
Questo è il file con il quale l’articolo è stato proposto alla rivista. Viene direttamente dal sito della rivista, ed è accessibile sotto la licenza “open access”, perciò non ci sono problemi legali.
http://www.retrovirology.com/content/6/1/52
Retrovirology. 2009 Jun 2;6(1):52
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Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deaceti...mabasta
Questo è il file con il quale l’articolo è stato proposto alla rivista. Viene direttamente dal sito della rivista, ed è accessibile sotto la licenza “open access”, perciò non ci sono problemi legali.
http://www.retrovirology.com/content/6/1/52
Retrovirology. 2009 Jun 2;6(1):52
http://www.biomedcentral.com/info/about/openaccess/
Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deaceti...mabasta
Questo è il file con il quale l’articolo è stato proposto alla rivista. Viene direttamente dal sito della rivista, ed è accessibile sotto la licenza “open access”, perciò non ci sono problemi legali.
http://www.retrovirology.com/content/6/1/52
Retrovirology. 2009 Jun 2;6(1):52
http://www.biomedcentral.com/info/about/openaccess/
Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deaceti...mabasta
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Una guida a: persistenza del virus hiv nei pazienti sottoposti a haart valuta...mabasta
Eccoci qua, ogni promessa è debito!
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Spero sia utile…
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A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
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Dive into an in-depth exploration of the histological structure of female reproductive system with this comprehensive lecture. Presented by Dr. Ayesha Irfan, Assistant Professor of Anatomy, this presentation covers the Gross anatomy and functional histology of the female reproductive organs. Ideal for students, educators, and anyone interested in medical science, this lecture provides clear explanations, detailed diagrams, and valuable insights into female reproductive system. Enhance your knowledge and understanding of this essential aspect of human biology.
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Lo studio “Shock and kill” sugli effetti degli inibitori delle istone deacetilasi oin combinazione con l’inibitore della sintesi del glutatione butiomina sulfoximina nel risvegliare dalla quiescienzale cellule che integrano HIV-1
2. “Shock and kill” effects of class I-selective histone deacetylase
inhibitors in combination with the glutathione synthesis inhibitor
buthionine sulfoximine in cell line models for HIV-1 quiescence
Andrea Savarino*1§ Antonello Mai,*2 Sandro Norelli1, Sary El Daker1, Sergio
Valente,2 Dante Rotili,2 Lucia Altucci,3 Anna Teresa Palamara2,5 and Enrico Garaci6.
Address: 1Dept. of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità,
Viale Regina Elena, 299, 00161, Rome, Italy, 2Pasteur Institute, Cenci-Bolognetti Foundation,
Dept. of Drug Chemistry and Technologies, Sapienza University of Rome, P.le A. Moro, 5, 00185,
Rome, Italy, 3Dept. of General Pathology, 2nd University of Naples, Vico L. De Crecchio 7, 80138
Naples, Italy, 5Pasteur Institute, Cenci-Bolognetti Foundation, Dept. of Public Health Sciences,
Sapienza University of Rome, P.le A. Moro, 5, 00185, Rome, Italy, 6Dept. of Experimental
Medicine, University of Rome Tor Vergata, Rome, Italy.
E-mail: Andrea Savarino: andrea.savarino@iss.it; Antonello Mai: antonello.mai@uniroma1.it; Sary
El Daker: saryeldaker@yahoo.it; Sandro Norelli: sandro.norelli@iss.it; Sergio Valente:
sergio.valente1977@libero.it; Dante Rotili: danterotili@libero.it; Lucia Altucci:
lucia.altucci@unina2.it; Anna Teresa Palamara: microbiologia.farmaceutica@uniroma1.it; Enrico
Garaci: presidenza@iss.it
*Equal contribution
§
Corresponding author
3. 2
Abstract
Latently infected, resting memory CD4+ T cells and macrophages represent a major obstacle to the
eradication of HIV-1. For this purpose, “shock and kill” strategies have been proposed (activation
of HIV-1 followed by stimuli leading to cell death). Histone deacetylase inhibitors (HDACIs)
induce HIV-1 activation from quiescence, yet class/isoform-selective HDACIs are needed to
specifically target HIV-1 latency. We tested 32 small molecule HDACIs for their ability to induce
HIV-1 activation in the ACH-2 and U1 cell line models. In general, potent activators of HIV-1
replication were found among non-class selective and class I-selective HDACIs. However, class I
selectivity did not reduce the toxicity of most of the molecules for uninfected cells, which is a major
concern for possible HDACI-based therapies. To overcome this problem, complementary strategies
using lower HDACI concentrations have been explored. We added to class I HDACIs the
glutathione-synthesis inhibitor buthionine sulfoximine (BSO), in an attempt to create an
intracellular environment that would facilitate HIV-1 activation. The basis for this strategy was that
HIV-1 replication decreases the intracellular levels of reduced glutathione, creating a pro-oxidant
environment which in turn stimulates HIV-1 transcription. We found that BSO increased the ability
of class I HDACIs to activate HIV-1. This interaction allowed the use of both types of drugs at
concentrations that were non-toxic for uninfected cells, whereas the infected cell cultures
succumbed more readily to the drug combination. These effects were associated with BSO-induced
recruitment of HDACI-insensitive cells into the responding cell population, as shown in Jurkat cell
models for HIV-1 quiescence. The results of the present study may contribute to the future design
of class I HDACIs for treating HIV-1. Moreover, the combined effects of class I-selective HDACIs
and the glutathione synthesis inhibitor BSO suggest the existence of an Achilles’ heel that could be
manipulated in order to facilitate the “kill” phase of experimental HIV-1 eradication strategies.
4. 3
Findings
Given the inability of antiretroviral therapy (ART) to eradicate HIV-1 from the body (even after
decade-long periods of therapy), and the absence of effective vaccines on the horizon, novel
approaches to HIV-1 eradication are needed. To this end, the so-called “shock and kill” strategies
have been proposed [1]. These strategies consist of inducing, through drugs, HIV-1 activation from
quiescence (i.e. the “shock” phase), in the presence of ART (to block viral spread), followed by the
elimination of infected cells (i.e. the “kill” phase), through either natural means (e.g. immune
response, viral cytopathogenicity) or artificial means (e.g. drugs, monoclonal antibodies, etc.) [1].
For the “shock” phase, histone deacetylase inhibitors (HDACIs) have been proposed [2]. Histone
deacetylases (HDACs) contribute to nucleosomal integrity by maintaining histones in a form that
has high affinity for DNA [3]. Physiologically, this activity is counteracted by histone acetyl
transferases (HATs) which are recruited to gene promoters by specific transcription factor-
activating stimuli [3].
Several of the currently available HDACIs activate HIV-1 from quiescence in vitro [4, 5]. However,
this activity is associated with a certain degree of toxicity [6], given that these inhibitors are not
class-specific and compromise a large number of cellular pathways [7, 8]. Class I HDACs comprise
HDAC1-3 and 8; they are predominantly nuclear enzymes and are ubiquitously expressed [9]. Class
II HDACs include HDAC4-7, 9 and 10 and shuttle between the nucleus and the cytoplasm [10, 11].
HDACs are recruited to the HIV-1 promoter by several transcription factors, including NF-κB
(p50/p50 homodimers), AP-4, Sp1, YY1 and c-Myc [12-14]. Identification of class/isoform-
selective HDACIs with increased potency and lower toxicity [3] and drugs able to potentiate their
effects is believed to be important for HIV-1 eradication.
To identify novel HDACIs capable of activating HIV-1, we first tested the HIV-1 activating ability
of our institutional library of HDACIs [see Additional file 1] in cell lines in which HIV-1 is
inducible (i.e. T-lymphoid ACH-2 cells and monocytic U1 cells). The potency of these molecules to
activate HIV-1 was assessed in terms of p24 production, as measured by ELISA (Perkin-Elmers,
5. 4
Boston, MA), following incubation with a drug concentration of 1 µM (generally used as a
threshold for selection of lead compounds). As a positive control, we used TNF-α (5 ng/ml), a
cytokine that activates HIV-1 transcription through NF-κB (p65/p50) induction [1]. As a reference
standard for the comparison of results, we used suberoylamide hydroxamic acid (SAHA; also
referred to as “vorinostat”), a non-specific inhibitor of both classes of HDACs when used in the
upper-nanomolar/micromolar range of concentrations [15].
The results revealed a number of compounds capable of activating HIV-1; and, for the most potent
compounds, there was good agreement between the results in the ACH-2 and U1 cells (Figure 1).
Only non-class selective and class I-selective HDACIs were significantly active (Figure 1), and
potent class I-selective HDACIs enhanced HIV-1 replication in the nanomolar range in a dose-
dependent manner (Figure 2). In general, class I selectivity was insufficient for eliminating toxicity,
although some of the compounds (e.g. MC2211) induced adequate HIV-1 activation and low-level
toxicity (Figure 1, 2). Of note, the class I-selective HDACIs that activated HIV-1 included MS-275,
an HDAC1-3-selective inhibitor currently being tested in phase II clinical trials as an anticancer
drug [15].
A previous study showed a trend towards higher toxicity of the HDACI trichostatin in ACH-2 cells
than in their uninfected counterparts and linked this phenomenon to the cytotoxicity of activated
HIV-1 replication in lymphoid cells [16]. In our experiments, three different class I HDACIs (i.e.
MS-275, MC2113 and MC2211) displayed lower CC50 in ACH-2 cells (Figure 2D) than in
uninfected CD4+ T cells (data from Jurkat cells are shown as an example in Figure 2E), yet the
extent of the difference did not support the possibility of a “therapeutic window”. The same
compounds displayed non-significant toxicity in U1 cells at concentrations up to 1 µM (Figure 2F).
In these experiments, an incubation period of 72 hours was preferred to shorter periods, because of
the intrinsically slow mode of action of epigenetic modulators, which only indirectly induce HIV-1
activation. This was confirmed by our experiments using Jurkat cell clones with an integrated green
fluorescence protein (GFP)-encoding gene under control of the HIV-1 LTR [17]. In these Jurkat cell
6. 5
clones, GFP induction by HDACIs was evident only in a fraction of cells at 24 hours of incubation
and increased over time [see Additional file 2].
To focus on the structural requirements for the most potent class I-selective HDACIs, we then
performed a structure/activity relationship (SAR) study. SAR studies relate the effect or the potency
of bioactive chemical compounds with their chemical structure and help to understand the structural
requirements for obtaining a desired effect. HDACIs are structured according to a general
pharmacophore model (i.e. quot;a molecular framework that carries the essential features responsible
for a drug’s biological activityquot; [18]) (Figure 3A). This pharmacophore model comprises a cap
group (CAP), a polar connection unit (CU), and a hydrophobic spacer (HS), which carries at its end
a Zn2+ binding group (ZBG), able to complex the Zn2+ at the bottom of the cavity [19]. The ZBG
consists of a hydroxamate, a sulfhydryl, or a benzamide moiety (Figure 3A shows a benzamide
inhibitor complexed with HDAC2). A general scaffold describing the characteristics of the most
potent HDACIs from our library is presented in Figure 3B, C. The differences in the general
structural requirements for the two main chemical types of HDACIs in our library (hydroxamates
and benzamides) can probably be attributed to the hydrophobicity/hydrophilicity balance (the more
hydrophobic benzamides require less hydrophobic CAP groups than hydroxamates do). The
molecular docking simulations, conducted as previously described [20,21], highlighted particular
requirements for the CU (Figure 3D). These requirements consisted of a uracil group or an amide
group in a cis-conformation, which presented the nitrogen-bond hydrogen and the carbonylic
oxygen on the same side of the molecule (usually amide groups are in a trans-conformation, with
the nitrogen-bond hydrogen and the carbonylic oxygen oriented in opposite directions) (Figure 3D).
SAHA, consistent with its non-specific inhibitory activity on HDACs [15], did not match the
characteristics of our pharmacophore model [see Additional file 3].
Given that class I selectivity, in general, did not markedly decrease the toxicity of HDACIs, we
have begun studies on complementary strategies that might increase the efficacy of class I HDACIs
at non-toxic concentrations. It is well known that HIV-1 induces a pro-oxidant status which in turn
7. 6
enhances the levels of HIV-1 transcription [22-25]. There are probably many mechanisms behind
HIV-1-induced oxidative stress, and the signals that it sparks are still far from being fully
understood [26]. In general, oxidative stress tilts the balance of HAT/HDAC activity towards
increased HAT activity and DNA unwinding, thus facilitating the binding of several transcription
factors [27]. The HIV-1–induced pro-oxidant status is in part mediated by decreased intracellular
levels of reduced glutathione [26, 28]. The depletion of reduced glutathione has been linked to
activation of viral replication [29], whereas the administration of this cofactor results in
antiretroviral effects [26]. We hypothesized that glutathione depletion might create an intracellular
environment that facilitates HIV-1 activation by HDACIs. To test this hypothesis, we evaluated the
HIV-1 activating effects of buthionine sulfoximine (BSO), which depletes glutathione by inhibiting
γ-glutamyl cysteine synthetase (a limiting step in glutathione synthesis) [27, 30].
BSO, at concentrations of up to 500 µM, did not significantly raise the p24 concentrations; yet it
increased the HIV-1 promoting effects of class I HDACIs, such as MS-275 (Figure 4A) and
MC2113 (data not shown) in ACH-2 cells (Figure 4A) and U1 cells (data not shown). According to
the literature, the concentrations of MS-275 and BSO adopted here are clinically achievable [31,
32]. The results shown in Figure 4A are based on a 24 hour incubation time, given the marked
cytotoxicity shown by the drug combination in the ACH-2 cells at 72 hours of incubation (Figure
4B). Since HIV-1 replicating cell cultures display decreased levels of reduced glutathione [29], their
poor tolerance to an inhibitor of glutathione synthesis is not surprising. This concept is supported by
experiments in uninfected Jurkat cells and Jurkat cell clones (6.3 and 8.4), which contain a
quiescent HIV-1 genome (with the GFP gene) under control of the LTR [17]. We found that the 6.3
cell clone succumbed more readily to the MS-275/BSO combination than its uninfected counterpart
(Figure 4 C, D). Similar results were obtained with the 8.4 clone (data not shown).
The Jurkat model for HIV-1 quiescence showed that BSO recruited HDACI-insensitive cells into
the responding cell population (Figure 5). These results are derived from the A1 Jurkat cell clone,
which has an integrated GFP/Tat construct under control of the HIV-1 LTR, which is quiescent in
8. 7
the majority of cells [17]. This clone was chosen because this type of analysis could not be
conducted in the 6.3 or 8.4 clones, since, at 24 hours of incubation with the drugs, these clones
displayed only a small proportion of cells expressing GFP, and a correct estimate of the expression
of this protein at subsequent time points was biased by the autofluorescence of dying cells. The A1
clone, which does not have a complete HIV-1 genome, was less sensitive to the toxic effects of the
MS-275/BSO combination than the 6.3 and 8.4 clones (data not shown).
To sum up, the combination of a class I-selective HDACI and BSO activates HIV-1 at
concentrations that show low toxicity in uninfected cells, and it induces cell death in infected cell
cultures. These results are consistent with a model in which BSO would favor the HIV-1 activating
effects of HDACIs by lowering the intracellular levels of reduced glutathione [30] and would
induce the death of infected cells by preventing replenishment of the reduced glutathione pools that
are further “consumed” by the virus activated from quiescence [28, 29]. If these results are
confirmed, the decreased pool of reduced glutathione may become an Achilles’ heel of the infected
cells, and its manipulation may open new avenues to their elimination.
This strategy will of course require optimization, and several issues still have to be addressed. First,
not all of the cells with a quiescent provirus respond to the treatment. A variegated phenotype after
activation, with only a fraction of the cell population becoming activated in response to a global
signal, was also shown by Jordan et al. [17], who attributed this phenomenon to the different local
chromatin environments. A thorough investigation of the molecular signals sparked by the
BSO/class I-selective HDACI combination (currently in progress in our laboratories) is expected to
provide insight into these phenomena. Moreover, the “therapeutic window” (i.e. the differential
toxicity in uninfected vs. infected cells) still needs to be widened. In this regard, the general
structural requirements for the HIV-1 activating HDACIs presented in our study, as well as the
recent identification of HDAC2 as a potential target for HIV-1 reactivation strategies [33], may
represent a good starting point for developing next-generation class I HDACIs with increased
selectivity and decreased toxicity. Finally, we are currently searching for novel γ-glutamyl-cysteine
9. 8
synthetase inhibitors acting in the nanomolar range and displaying lower toxicity than BSO in
uninfected cells.
The concept to activate provirus transcription to target latency is not new, and several clinical trials
have been conducted in the past years along this line, ranging from the administration of IL-2 to the
utilization of valproic acid [34-36]. The results of these trials have been largely disappointing so far.
Valproic acid, a relatively weak HDACI, was tested in a small clinical trial in combination with
antiretroviral therapy intensified with the fusion inhibitor enfuvirtide [35, 36], but some more recent
studies have failed to show a decay of resting CD4+ T cell infection in individuals under valproic
acid treatment for clinical reasons while also receiving standard ART [37]. Our study provides a
potentially more powerful approach for the “shock” phase of experimental HIV-1 eradicating
strategies and a potential tool for the “kill” phase. Notwithstanding the aforementioned need for
amelioration, it is interesting to point out that both MS-275 and BSO have passed class I clinical
trials for safety in humans and are therefore ready for testing in animal models. Such testing would
be important at a time when no proof-of-concept exists for the “shock and kill” theory. In this
regard, even a partial response (e.g. a reduction in latently infected cells) would be a valuable
indicator of the validity of this approach. The possible efficacy of the “shock and kill” approach is
still a matter of debate. For example, a recent study of Jeeninga et al. suggests that there are
different cellular reservoirs for HIV-1 latency and that each reservoir may require a specific
activation strategy [38]. Viral factors, along with cellular factors, may contribute to HIV-1
quiescence, and these factors may not be controlled by strategies using HDACIs.
Competing interests
AS, AM, ATP, and EG have requested patent rights on several compounds described in the present
study and on the MS-275/BSO combination.
10. 9
Authors’ contributions
AS conceived and coordinated the study, supervised the generation of biological data, conducted
the molecular docking, analyzed the data and drafted the manuscript. AM conceived the majority of
the structures described in the present study, supervised their synthesis and participated in
manuscript drafting. SN and SED conducted the biological testing and contributed to molecular
modeling and data analysis. SV, DR, and LA conducted synthesis and development of the HDACi.
LA conducted the HDAC inhibitory assays. ATP and EG contributed the idea of using BSO for
HIV-1 escape from latency and participated in the experimental planning.
Acknowledgements
The authors are thankful to Mr. Federico Mele, Rome, Italy, and Ms. Dora Pinto, ibidem, for
technical help, Ms. Maria Grazia Bedetti, ibidem, for administrative support, and Dr. Mark Kanieff,
ibidem, for the linguistic revision. This work was partially supported by grants from Special Project
AIDS-Italian Ministry of Health (AS), FIRB 2006 (ATP), PRIN 2006 (AM), European Union
(Epitron LSHC-CT2005-518417; Apo-sys HEALTH-F4-2007-200767) (LA), and PRIN 2006 and
AIRC (LA). Special thanks to Dr. Marco Sgarbanti, Rome, Italy, and Dr. Marina Lusic, Trieste,
Italy, for providing reagents and illuminating discussion. We finally would like to acknowledge the
AIDS Reagent Program (Bethesda, MD) as the source of the Jukat clones used in this study.
References
1. Hamer DH: Can HIV be Cured? Mechanisms of HIV persistence and strategies to combat it.
Curr HIV Res 2004, 2:99-111.
2. Demonté D, Quivy V, Colette Y, Van Lint C: Administration of HDAC inhibitors to
reactivate HIV-1 expression in latent cellular reservoirs: implications for the development of
therapeutic strategies. Biochem Pharmacol 2004, 68:1231-1238.
11. 10
3. Rotili D, Simonetti G, Savarino A, Palamara AT, Migliaccio AR, Mai A: Non-cancer uses of
histone deacetylase inhibitors: effects on infectious diseases and β-hemoglobinopathies. Curr
Topics Med Chem 2009, 9:272-291.
4. Richman DD, Margolis DM, Delaney M, Greene WC, Hazuda D, Pomerantz RJ: The challenge
of finding a cure for HIV infection. Science 2009, 323:1304-1307.
5. Mai A, Altucci L: Epi-drugs to fight cancer: From chemistry to cancer treatment, the road
ahead. Int J Biochem Cell Biol 2009, 41:199-213.
6. Duverger A, Jones J, May J, Bibollet-Ruche F, Wagner FA, Cron RQ, Kutsch O: Determinants
of the establishment of human immunodeficiency virus type 1 latency. J Virol 2009, 83:3078-
3093.
7. Dokmanovic M, Clarke C, Marks PA: Histone deacetylase inhibitors: overview and
perspectives. Mol Cancer Res 2007, 5:981-989.
8. Bolden JE, Peart MJ, Johnstone RW: Anticancer activities of histone deacetylase inhibitors.
Nat Rev Drug Discov 2006, 5:769-784.
9. De Ruijter A JM, Van Gennip AH, Caron HN, Kemp S, Van Kuilemburg ABP: Histone
deacetylases (HDACs): Characterization of the classical HDAC family. Biochem J 2003,
370:737-749.
10 . Verdin E, Dequiedt F, Kasler G: Class II histone deacetylases: versatile regulators. Trends
Genet 2003, 19:5286-5293.
11. Mai A: The therapeutic uses of chromatin-modifying agents. Expert Opin Ther Targets
2007, 11:835-851.
12. Williams SA, Greene WC: Regulation of HIV-1 latency by T-cell activation. Cytokine 2007,
39:63-74.
13. Imai K, Okamoto T: Transcriptional repression of human immunodeficiency virus type 1
by AP-4. J Biol Chem 2006, 281:12495-12505.
12. 11
14. Jiang G, Espeseth A, Hazuda DJ, Margolis DM: c-Myc and Sp1 contribute to proviral
latency by recruiting histone deacetylase 1 to the human immunodeficiency virus type 1
promoter. J Virol 2007, 81:10914-10923.
15. Khan N, Jeffers M, Kumar S, Hackett C, Boldog F, Khramtsov N, Qian X, Mills E, Berghs SC,
Carey N, Finn PW, Collins LS, Tumber A, Ritchie JW, Jensen PB, Lichenstein HS, Sehested M:
Determination of the class and isoform selectivity of small-molecule histone deacetylase
inhibitors. Biochem J 2008, 409:581-589.
16. Vandergeeten C, Quivy V, Moutschen M, Van Lint C, Piette J, Legrand-Poels S: HIV-1
protease inhibitors do not interfere with provirus transcription and host cell apoptosis
induced by combined treatment TNF-alpha + TSA. Biochem Pharmacol 2007, 73:1738-1748.
17. Jordan A, Bisgrove D, Verdin E: HIV reproducibly establishes a latent infection after acute
infection of T cells in vitro. EMBO J 2003, 22:1868-1877.
18. Ehrlich P: Über den jetzigen Stand der Chemotherapie. Dtsch. Chem. Ges. 1909, 42: 17-47.
19. Mai A, Massa S, Rotili D, Pezzi R, Bottoni P, Scatena R, Meraner J, Brosch G: Exploring the
connection unit in the HDAC inhibitor pharmacophore model: novel uracil-based
hydroxamates. Bioorg Med Chem Lett 2005, 15:4656-4661.
20. Savarino A, Pistello M, D'Ostilio D, Zabogli E, Taglia F, Mancini F, Ferro S, Matteucci D, De
Luca L, Barreca ML, Ciervo A, Chimirri A, Ciccozzi M, Bendinelli M: Human immunodeficiency
virus integrase inhibitors efficiently suppress feline immunodeficiency virus replication in
vitro and provide a rationale to redesign antiretroviral treatment for feline AIDS.
Retrovirology 2007, 4:79.
21. Savarino A: In-Silico docking of HIV-1 integrase inhibitors reveals a novel drug type
acting on an enzyme/DNA reaction intermediate. Retrovirology 2007, 4:21.
22. Masutani H: Oxidative stress response and signaling in hematological malignancies and
HIV infection. Int J Hematol 2000, 71:25-32.
13. 12
23. Israël N, Gougerot-Pocidalo MA: Oxidative stress in human immunodeficiency virus
infection. Cell Mol Life Sci 1997, 53:864-870.
24. Savarino A, Pescarmona GP, Boelaert JR: Iron metabolism and HIV infection: reciprocal
interactions with potentially harmful consequences? Cell Biochem Funct 1999, 17:279-287.
25. Perl A, Banki K: Genetic and metabolic control of the mitochondrial transmembrane
potential and reactive oxygen intermediate production in HIV disease. Antioxid Redox Signal
2000, 2:551-573.
26. Fraternale A, Paoletti MF, Casabianca A, Nencioni L, Garaci E, Palamara AT, Magnani M:
GSH and analogs in antiviral therapy. Mol Aspects Med 2008, 30:99-110.
27. Rahman I, Marwick J, Kirkham P: Redox modulation of chromatin remodeling: impact on
histone acetylation and deacetylation, NF-kappaB and pro-inflammatory gene expression.
Biochem Pharmacol 2004, 68:1255-1267.
28. Garaci E, Palamara AT, Ciriolo MR, D'Agostini C, Abdel-Latif MS, Aquaro S, Lafavia E,
Rotilio G: Intracellular GSH content and HIV replication in human macrophages. J Leukoc
Biol 1997, 62:54-59.
29. Simon G, Moog C, Obert G: Valproic acid reduces the intracellular level of glutathione and
stimulates human immunodeficiency virus. Chem Biol Interact 1994, 91:111-121.
30. Anderson ME: Glutathione: an overview of biosynthesis and modulation. Chem Biol
Interact 1998, 111-112:1-14.
31. Zhao M, Rudek MA, Mnasakanyan A, Hartke C, Pili R, Baker SD: A liquid
chromatography/tandem mass spectrometry assay to quantitate MS-275 in human plasma. J
Pharm Biomed Anal 2007, 43:784-787.
32. Lacreta FP, Brennan JM, Hamilton TC, Ozols RF, O'Dwyer PJ: Stereoselective
pharmacokinetics of L-buthionine SR-sulfoximine in patients with cancer. Drug Metab Dispos
1994, 22:835-842.
14. 13
33. Keedy KS, Archin NM, Gates AT, Espeseth A, Hazuda DJ, Margolis DM: A limited group of
class I histone deacetylases act to repress human immunodeficiency virus type-1 expression. J
Virol 2009, 83:4749-4756.
34. Stellbrink HJ, van Lunzen J, Westby M, O'Sullivan E, Schneider C, Adam A, Weitner L,
Kuhlmann B, Hoffmann C, Fenske S, Aries PS, Degen O, Eggers C, Petersen H, Haag F, Horst HA,
Dalhoff K, Möcklinghoff C, Cammack N, Tenner-Racz K, Racz P. Effects of interleukin-2 plus
highly active antiretroviral therapy on HIV-1 replication and proviral DNA (COSMIC trial).
AIDS 2002, 16:1479-1487.
35. Lehrman G, Hogue IB, Palmer S, Jennings C, Spina CA, Wiegand A, Landay AL, Coombs RW,
Richman DD, Mellors JW, Coffin JM, Bosch RJ, Margolis DM: Depletion of latent HIV-1
infection in vivo: a proof-of-concept study. Lancet 2005, 366:523-524.
36. Smith SM: Valproic acid and HIV-1 latency: beyond the sound bite. Retrovirology 2005,
2:56.
37. Sagot-Lerolle N, Lamine A, Chaix ML, Boufassa F, Aboulker JP, Costagliola D, Goujard C,
Pallier C, Delfraissy JF, Lambotte O; ANRS EP39 study. Prolonged valproic acid treatment does
not reduce the size of latent HIV reservoir. AIDS 2008, 22:1125-1129.
38. Jeeninga RE, Westerhout EM, van Gerven ML, Berkhout B. HIV-1 latency in actively
dividing human T cell lines. Retrovirology 2008, 5:37.
15. 14
Figure legends
Figure 1. Potencies of different HDACIs in terms of activation of HIV-1 replication in U1 and
ACH-2 cells, and toxicity in uninfected Jurkat T-cells.
Panel A: Cells were incubated with the test compounds (1 µM), and p24 production was measured
by ELISA in cell culture supernatants at 72 hours post-infection (means ± SEM; 3 experiments).
Asterisks show the significant differences in comparison to untreated control cultures according to
repeated-measures ANOVA using Dunnet’s multiple comparison post-test (a Log transformation of
p24 values was applied to restore normality). Panel B: Uninfected Jurkat T cells were incubated for
72 h under similar conditions, and toxicity was measured by the methyl tetrazolium (MTT) method.
Results are presented as a percentage of the O.D. (λ = 550) of untreated controls subtracted of
background (means ± SEM; 3 experiments). Asterisks show the significant differences in
comparison to untreated control cultures according to repeated-measures ANOVA using Dunnet’s
multiple comparison post-test.
Figure 2. Dose-dependent activation of HIV-1 replication by class I-selective HDACIs and
corresponding toxicity in U1 and ACH-2 cells
Panels A,B: Concentration-dependent stimulation of HIV-1 p24 production in the latently infected
cell lines U1 (A) and ACH-2 (B) at 72 hours of incubation with MS-275, MC2211, MC2113 (class
I-selective HDACIs) and SAHA (a non-class-selective HDACI used as a positive control). Mean
values are from three independent experiments (error bars are not shown for better clarity). Dotted
lines represent the average p24 levels found in untreated controls in the same experiments. Panel C.
Effective concentrations for increasing viral replication to 500% of the basal levels of untreated
controls (EC500). Panel D: Cell viability of ACH-2 cells, as measured by the methyl tetrazolium
(MTT) method. Results are presented as a percentage of the O.D. (λ = 550) of untreated controls
subtracted for background (means ± SEM; 3 experiments). Panel E: Cell viability of uninfected
16. 15
Jurkat T cells incubated for 72 hours with the same drugs is shown as comparison. Panel F. 50%
cytotoxic concentrations (CC50). For the symbols in panels D,E, the reader should refer to those of
panels A,B.
Figure 3. Structural characteristics of HIV-1 activating HDACIs
Panel A: Docking of the HDACI MC2211 at the catalytic cavity of HDAC2, a class I enzyme. The
different portions of the inhibitor [i.e. the CAP portion (CAP), the connection unit (CU), the
hydrophobic spacer (HS), and the zinc-binding group (ZBG)] are mapped to the molecule
represented in the picture. The enzyme is shown as semi-transparent Connolly surface. The Zn++ ion
embedded in the catalytic cavity is shown as a dotted sphere. The inhibitor is shown according to
CPK colouring. General formulas for HDACIs capable of inducing HIV-1 activation from
quiescence. Panel D: Structural superimposition of the best docking poses for the HDACIs MC2113
and MC2211 within the catalytic cavity of HDAC2. Inhibitors are shown in CPK (MC2113: carbon
backbone in white; MC2211: carbon backbone in cyan). The enzyme backbone is shown as
cartoons. The Zn++ ion is shown as a gray sphere. Amino acids D100, H141 and G150 (important
for hydrogen bonding with the inhibitors) are shown as orange sticks.
Figure 4. Effects on HIV-1 replication and cell viability of class I-selective HDACIs, MS-275
and buthionine sulfoximine (BSO), alone or in combination. Panel A: HIV-1 p24 concentrations
in ACH-2 cell culture supernatants at 24 hours of incubation with the drugs. Panels B-D: Cell
viability values at 72 hours of incubation, as determined by the methyl tetrazolium (MTT) method:
ACH-2 cells (B), Jurkat 6.3 cells (C), uninfected Jurkat cells (D). Results are presented as
percentages of the absorbance (λ = 550) in untreated controls subtracted for background (means ±
SEM; 3 experiments). Asterisks show the significant differences found between BSO treatments
and matched treatments in the absence of BSO (* P < 0.05; ** P < 0.01; *** P < 0.001). Statistical
significance was calculated using repeated-measures, two-way ANOVA and Bonferroni’s post-test,
17. 16
following an appropriate transformation to restore normality, where necessary. The higher drug
concentrations adopted in Panels C,D serve as comparisons with the experiment in Figure 5.
Figure 5. Stimulation of HIV-1 LTR-controlled expression of green fluorescent protein (GFP)
by MS-275 and buthionine sulfoximine (BSO), alone or in combination in a Jurkat cell clone
(A1). The A1 cell clone, derived from T-lymphoid Jurkat cells, is a model for latent HIV-1
infection. This clone has an integrated GFP/Tat construct under the control of the HIV-1 LTR and
displays a basal proportion of cells expressing GFP, which increase following stimuli activating the
HIV-1 promoter. A1 cells were incubated for 72 hours with the different treatments, and GFP
expression was monitored by standard flow-cytometric techniques and assessed as the percentage of
fluorescent cells (indicated for each histogram) beyond the threshold value established using control
non-transfected Jurkat cells. One experiment out of three with similar results is shown. The
histograms derived from double-drug treatments were found to be significantly different (P < 0.01)
from those derived from treatments with a single drug at matched concentrations (Kolmogorov-
Smirnoff statistics). Differences between the drug concentrations adopted in this experiment and
that in Figure 4A are derived from adjustments due to the different nature of the cell lines adopted.
Additional files
Additional file 1
File format: DOC
Title: Additional file 1
Description: Structures and HDAC inhibiting activity of the cited HDACIs. Where data on human
HDACs are unavailable, data on maize HD1-B (homologous with human class I HDACs) and HD1-
A (homologous with human class II HDACs), or relevant references, are provided.
Additional file 2
18. 17
File format: PPT
Title: Additional file 2
Description: To study the HDACI response in a cell population, we used quiescently infected T-
lymphoid Jurkat cell clones. Two types of cell clones were used: 1) A1, and A2, which have an
integrated GFP/Tat construct under control of the HIV-1 LTR; 2) 6.3, and 8.4, which contain the
entire HIV-1 genome under control of the LTR and have the GFP gene replacing nef. The 6.3 cells
display insignificant basal levels of GFP expression. Cells were incubated with the different
treatments, and GFP expression was monitored in gated live cells at 12, 24 and 72 hours by
standard flow cytometric techniques. Results are presented as fluorescence histograms. Each
histogram reports the percentage of fluorescent cells beyond a threshold value established using
non-infected Jurkat cells.
Additional file 3
File format: PNG
Title: Additional file 3
Description: Structural superimposition of MC2211 (carbon backbone in cyan) and SAHA
(vorinostat; carbon backbone in yellow) docking at the HDAC2 catalytic site. SAHA, a non-
selective HDACI, displays an amide group in a conformation that does not match that of the class I-
selective HDACIs (Figure 2). The other molecular players are displayed in the same fashion as in
Figure 3.