This study investigated the effects of the antioxidant baicalein on the pharmacokinetics of the calcium channel blocker nimodipine in rats. Baicalein inhibited the activity of CYP3A4, a key enzyme involved in nimodipine metabolism, in a concentration-dependent manner. It also enhanced the accumulation of a P-glycoprotein substrate, suggesting it inhibits this efflux transporter. When administered with oral nimodipine, baicalein significantly increased nimodipine bioavailability by inhibiting its intestinal and hepatic metabolism and intestinal efflux, without affecting intravenous nimodipine pharmacokinetics. This drug-drug interaction between baicalein and nimodipine could impact their combined
Protein and-peptide-drug-delivery-systemsGaurav Kr
The document discusses protein and peptide drug delivery systems. It begins by defining proteins and peptides, noting that proteins are molecules composed of over 50 amino acids, while peptides are molecules composed of less than 50 amino acids. It then discusses how scientific advances in molecular and cell biology have led to the development of recombinant DNA and hybridoma technology to produce protein products. The document provides examples of marketed protein and peptide drugs and discusses challenges with delivering these drugs orally due to their large molecular size and susceptibility to enzymatic degradation. It explores approaches to protein and peptide delivery including non-parenteral systemic delivery methods and various considerations for developing delivery systems for these pharmaceuticals.
The all the content in this profile is completed by the teachers, students as well as other health care peoples.
thank you, all the respected peoples, for giving the information to complete this presentation.
this information is free to use by anyone.
Protein and peptide drug delivery seminar-97-2003-final2Pravin Chinchole
The document discusses protein and peptide drug delivery. It covers the introduction to proteins and peptides, routes of absorption, properties that present challenges for delivery, and various pharmaceutical approaches to overcome these challenges. These approaches include chemical modification through prodrug approaches, use of enzyme inhibitors, penetration enhancers, and formulation vehicles like dry emulsions, microspheres, liposomes and nanoparticles. It also discusses stability aspects and recent advances in delivery of therapeutic proteins and peptides.
1) Peptic ulcer occurs in the stomach and duodenum where gastric acid and pepsin are present.
2) Factors like H. pylori infection, psychosomatic issues, and vascular or humoral imbalances can contribute to ulcer formation.
3) Treatment includes H2 antagonists, proton pump inhibitors, and anti-H. pylori drugs to relieve symptoms, promote healing, and prevent recurrence.
This document summarizes a presentation on protein and peptide drug delivery systems. It discusses the importance of pre-formulation and formulation considerations for proteins and peptides, including toxicity, immunogenicity, and stability from regulatory perspectives. The key points covered include the definition of proteins and peptides, common formulation excipients to prevent denaturation like serum albumin and amino acids, and analytical techniques used for characterization like UV spectroscopy, electrophoresis and liquid chromatography. Maximizing oral absorption through chemical modifications like hydrophobization is also summarized.
Prodrug approaches for cns delivery ppt finished copyAtul Thakur
This document discusses prodrug approaches for central nervous system (CNS) drug delivery. It covers various prodrug concepts including increasing lipophilicity to enhance passive diffusion across the blood-brain barrier (BBB), utilizing endogenous transporters for carrier-mediated delivery, overcoming efflux transport, and antibody or gene-directed targeted therapies. The key roles of prodrug bioconversion kinetics and competing elimination processes are also addressed. Overall, the document provides an overview of rational chemistry and biology-based strategies to improve brain delivery of CNS therapeutics.
Protein and-peptide-drug-delivery-systemsGaurav Kr
The document discusses protein and peptide drug delivery systems. It begins by defining proteins and peptides, noting that proteins are molecules composed of over 50 amino acids, while peptides are molecules composed of less than 50 amino acids. It then discusses how scientific advances in molecular and cell biology have led to the development of recombinant DNA and hybridoma technology to produce protein products. The document provides examples of marketed protein and peptide drugs and discusses challenges with delivering these drugs orally due to their large molecular size and susceptibility to enzymatic degradation. It explores approaches to protein and peptide delivery including non-parenteral systemic delivery methods and various considerations for developing delivery systems for these pharmaceuticals.
The all the content in this profile is completed by the teachers, students as well as other health care peoples.
thank you, all the respected peoples, for giving the information to complete this presentation.
this information is free to use by anyone.
Protein and peptide drug delivery seminar-97-2003-final2Pravin Chinchole
The document discusses protein and peptide drug delivery. It covers the introduction to proteins and peptides, routes of absorption, properties that present challenges for delivery, and various pharmaceutical approaches to overcome these challenges. These approaches include chemical modification through prodrug approaches, use of enzyme inhibitors, penetration enhancers, and formulation vehicles like dry emulsions, microspheres, liposomes and nanoparticles. It also discusses stability aspects and recent advances in delivery of therapeutic proteins and peptides.
1) Peptic ulcer occurs in the stomach and duodenum where gastric acid and pepsin are present.
2) Factors like H. pylori infection, psychosomatic issues, and vascular or humoral imbalances can contribute to ulcer formation.
3) Treatment includes H2 antagonists, proton pump inhibitors, and anti-H. pylori drugs to relieve symptoms, promote healing, and prevent recurrence.
This document summarizes a presentation on protein and peptide drug delivery systems. It discusses the importance of pre-formulation and formulation considerations for proteins and peptides, including toxicity, immunogenicity, and stability from regulatory perspectives. The key points covered include the definition of proteins and peptides, common formulation excipients to prevent denaturation like serum albumin and amino acids, and analytical techniques used for characterization like UV spectroscopy, electrophoresis and liquid chromatography. Maximizing oral absorption through chemical modifications like hydrophobization is also summarized.
Prodrug approaches for cns delivery ppt finished copyAtul Thakur
This document discusses prodrug approaches for central nervous system (CNS) drug delivery. It covers various prodrug concepts including increasing lipophilicity to enhance passive diffusion across the blood-brain barrier (BBB), utilizing endogenous transporters for carrier-mediated delivery, overcoming efflux transport, and antibody or gene-directed targeted therapies. The key roles of prodrug bioconversion kinetics and competing elimination processes are also addressed. Overall, the document provides an overview of rational chemistry and biology-based strategies to improve brain delivery of CNS therapeutics.
This document discusses proteins and peptides as drug delivery systems. It covers the structure and classification of proteins, as well as stability problems such as denaturation, aggregation, oxidation, and proteolysis. Common excipients used to address these issues are presented. Several marketed protein and peptide drugs are listed along with their formulations and medical applications. The conclusion emphasizes that protein and peptide drugs will replace many existing pharmaceuticals, posing a challenge to develop viable delivery systems for non-parenteral administration.
Drug and gene delivery vehicles are biocompatible devices that can carry therapeutic components in the body. Synthetic vehicles include block copolymers, liposomes, dendrimers, and magnetic nanoparticles. Block copolymers form micelles with hydrophobic cores that can encapsulate drugs. Liposomes are phospholipid vesicles that can encapsulate both hydrophilic and hydrophobic drugs. Dendrimers are nanoscale polymers that can be functionalized to target drugs. Magnetic nanoparticles can be used for drug delivery, hyperthermia cancer treatment, and as MRI contrast agents. These vehicles aim to improve drug bioavailability and targeting while decreasing toxicity.
This document discusses protein and peptide drug delivery systems. It begins by defining proteins and peptides, and describing their structures. It then discusses various challenges in delivering protein and peptide drugs, such as stability issues like denaturation, aggregation, oxidation, and proteolysis. It also categorizes different drug delivery routes like parenteral, pulmonary, transdermal, and oral. Finally, it provides examples of marketed protein and peptide drug formulations and discusses strategies to improve stability and delivery of these drugs.
Biotransformation, or metabolism, refers to the chemical alteration of drugs in the body. The primary site is the liver, where drugs undergo two main phases of metabolism - phase I and phase II reactions. Phase I reactions like oxidation and hydrolysis functionally alter drugs, while phase II or conjugation reactions make drugs more polar and excretable by conjugating them to other molecules. Many drugs are activated or inactivated in these metabolic pathways. Metabolism can occur in other tissues as well and is mediated by various enzyme systems like the cytochrome P450 enzymes. Drug metabolism can be inhibited or induced, affecting the activity of other drugs a patient may be taking.
Protein and peptide are biopolymers which yield more than two amino acids on hydrolysis.
Although the terms ‘proteins’ and ‘peptides’ are used freely, peptides are those with molecular weight below 10,000 and proteins are molecules with higher molecular weight.
Most therapeutic proteins and peptide-based drugs are administered by parenteral route and are incorporated in liposomes to prolong their action or fused with Immunoglobulins or Albumin to improve their half-life.
PEGylation is a proven technique for improving the potentials of Proteins/peptide delivery systems.
ANTIOXIDANT ACTIVITY AND HEPATOPROTECTIVE EFFECTOF POMEGRANATE PEEL AND WHEY...Anurag Raghuvanshi
The antioxidant activity of pomegranate peel powder (PPP) and whey powder (WP) was evaluated, their hepatoprotective effect of each alone or in combination (PPWP) at equal levels was also evaluated in Wistar rats against carbon tetrachloride (CCL4) induced liver injury.
The hepatoprotective activity was assessed using various biochemical parameters and histopathological studies.
PLGA is a biodegradable and biocompatible copolymer of PLA and PGA that is widely used for controlled drug delivery. It can be synthesized via melt polycondensation or ring opening polymerization to produce copolymers of varying molecular weight and properties. PLGA nanoparticles are effectively used to encapsulate drugs and provide sustained release over time. The drug release kinetics from PLGA nanoparticles are dependent on factors like polymer composition, drug loading, particle size and shape. PLGA degrades via hydrolysis of its ester linkages into biocompatible monomers. Alpha-1 antitrypsin encapsulated in PLGA nanoparticles is a promising approach for pulmonary delivery to treat lung diseases.
This document discusses biotransformation, or the metabolism, of drugs in the body. It defines biotransformation as the chemical conversion of drugs from one form to another. The major organs involved in drug metabolism are the liver, lungs, kidneys, intestine, and placenta. The enzymes responsible for drug metabolism are divided into microsomal and non-microsomal enzymes. Drug metabolism occurs in two phases - phase I involves processes like oxidation and hydrolysis, while phase II involves conjugation reactions like glucuronidation and sulfation. Factors like the drug's physicochemical properties, genetic factors, age, and diet can influence a drug's metabolism in the body.
This document discusses proteins and peptides, their structures and functions. It provides examples of proteins and peptides used for various purposes like erythropoietin for red blood cell production and insulin for maintaining blood sugar levels. It then discusses challenges with oral delivery of proteins and peptides like degradation in the gastrointestinal tract. Various approaches to overcome these challenges are described, such as modifying the peptide structure, adding lipid chains to increase permeability, and using enzyme inhibitors and absorption enhancers. Specific examples of formulations using these approaches are also provided.
Protein and peptides drug delivery systemsVINOTH R
This document provides an overview of protein and peptide drug delivery. It discusses the structure of proteins and peptides, which consist of amino acids linked by peptide bonds. Various drug delivery techniques for proteins are described, including polymer, liposome, hydrogel, and emulsion-based systems. Challenges in delivering proteins include instability, degradation, and poor absorption. The document also discusses pumps, barriers to delivery, manufacturing, stability testing, instability issues, and some marketed protein and peptide drugs.
Practical consideration of protien and peptidesSuchandra03
This document summarizes a seminar on practical considerations for protein and peptide drug delivery. It begins with an introduction discussing the two main pathways of protein delivery research: non-invasive delivery methods and increasing drug half-life. It then covers the major barriers to protein delivery such as poor permeability, degradation, and stability issues. The document reviews protein structure, classification, properties, degradation pathways, and the rationale for protein drug delivery. It discusses various delivery strategies including chemical modifications, formulation vehicles, advancement like molecular conjugation and encapsulation, and considers toxicity, commercialization factors, and concludes discussing the challenges of oral protein delivery.
Pharmacokinetics and pharmacodynamics of protiens and peptidesSachinkumarBhairagon
This document discusses the pharmacokinetics and pharmacodynamics of proteins and peptides. It covers their administration pathways including injection, inhalation, and transdermal delivery. It describes their distribution throughout the body, with factors like protein binding and active transport processes affecting their volume of distribution. The document outlines their elimination, primarily through metabolism by proteases and peptidases in the gastrointestinal tract, liver, and kidneys, breaking them down into amino acids. It also briefly discusses pharmacodynamics, focusing on the drug-receptor interaction and subsequent physiological effects.
This document provides an overview of prodrug design and practical considerations. It defines prodrugs as chemically inert precursors that release the active pharmacological compound. Prodrugs are classified based on their carrier and linker groups. The rationale for prodrug design includes improving solubility, enhancing membrane permeability, reducing pre-systemic metabolism, and targeting delivery to specific sites. Practical considerations for prodrug design involve the use of ester, amide, phosphate and carbamate groups to link the drug. The document discusses several examples of prodrugs and their advantages over parent drugs.
This document discusses prodrugs, which are biologically inert derivatives of drug molecules that undergo conversion in vivo to release the active parent drug. Prodrugs can help overcome issues like poor solubility, stability, absorption and toxicity. They are designed to improve pharmaceutical, pharmacokinetic and pharmacodynamic properties. The concepts of carrier-linked prodrugs, mutual prodrugs, bioprecursor prodrugs and polymeric prodrugs are explained. The objectives of prodrug design like improving formulation, absorption and safety are covered. In conclusion, prodrug design is an important part of drug development that can enhance clinical effectiveness by overcoming undesirable properties.
This document provides an overview of metabolism and biotransformation. It defines key terms like metabolism, biotransformation, and xenobiotics. It describes the major sites of drug metabolism as the liver and secondary sites like the kidneys, lungs, and intestines. It outlines the two phases of biotransformation - phase I involving oxidation, reduction, and hydrolysis, and phase II involving conjugation reactions. Several examples of phase I and II enzyme systems and reactions are provided. The document also discusses enzyme induction and inhibition and their clinical importance in drug metabolism.
proteins are chains of amino acids, each joined to it
neighbor by a specific type of covalent bond. The
polymerization of L-α-amino acids by peptide
bonds forms the structural framework of proteins. The
term protein is used for molecules composed of over 50
amino acids. The term peptide is used for molecules
composed of less than 50 amino acids.
The chemical and structural complexities involved
demand an effective delivery system in which the
physicochemical and biologic properties, including
molecular size, conformational stability, solubility,
sensitivity to light, moisture and heat, biological half-life,
immunogenicity, dose requirements, susceptibility to
break down in both physical and biological environments,
requirement for specialized mechanisms for transport
across biological membranes are to be considered.
Peptide and Protein Structure
It is essential to have an idea about structure of protein
and peptide in order to deal with various problems
encountered while developing drug delivery system.
The proteins are relatively large molecules with complex
structure. The peptide chains in peptides and proteins are
seldom linear and adapt a variety of specific folded three
dimensional patterns and conformations.
All peptides and proteins are polymers of amino acids
connected via amide linkages referred to as peptide
bonds.
• Primary structure: It denotes the number and
specific sequence of amino acids.
• Secondary structure: Arrangement of individual
amino acids along the polypeptide backbone.
• Tertiary structure: Three dimensional
arrangement of a single protein molecule.
• Quaternary structure: Proteins that contain two
or more polypeptide chains associated by noncovalent
forces
Protein And Peptide Drug Delivery SystemKushal Saha
1) The document discusses protein and peptide drug delivery systems. It describes the structures of proteins, the need for effective delivery of proteins and peptides to overcome barriers like enzymatic degradation, and challenges like molecular size and stability.
2) Various delivery routes are covered including oral, buccal, nasal, pulmonary, transdermal and parental. Approaches to enhance delivery through each route like penetration enhancers, nanoparticles, and conjugates are summarized.
3) Key applications of protein and peptide drugs in cardiovascular, CNS, GI and immune systems are highlighted. Stability considerations like oxidation, deamination and hydrolysis are also discussed.
Clinical pharmacokintics part 2 dr jayesh vaghelajpv2212
This document discusses biotransformation and drug metabolism. It begins by introducing biotransformation as the biochemical transformation of drugs within living organisms catalyzed by enzymes. This allows insoluble compounds to become water soluble and be easily excreted. It then covers the phases of drug metabolism and the enzymes involved such as cytochrome P450 and discusses factors that can affect drug metabolism like age, sex, nutrition, and drug-drug interactions. Finally, it addresses the importance of understanding drug metabolism in the drug development process.
The document discusses three main topics:
1) How the number of hydroxyl groups on flavonols affects their binding affinity to serum albumin, with more hydroxyl groups increasing binding.
2) Glycosylation of flavonoids decreases their binding affinity to serum albumin by 1-3 orders of magnitude by introducing steric hindrance.
3) EGCG strongly binds to serum albumin and enhances the interaction of huperzine A, an acetylcholinesterase inhibitor, with serum albumin, potentially improving its transport and effects.
This document discusses plant-derived anticancer agents that are currently used in clinical practice or show promise as future treatments. It summarizes several prominent plant-derived compounds that are used clinically to treat various cancers, including vincristine, vinblastine, paclitaxel, camptothecin, and podophyllotoxin derivatives. It also outlines some challenges with developing plant-derived anticancer drugs and the process of isolating active compounds from plants and testing their efficacy and safety.
This document discusses proteins and peptides as drug delivery systems. It covers the structure and classification of proteins, as well as stability problems such as denaturation, aggregation, oxidation, and proteolysis. Common excipients used to address these issues are presented. Several marketed protein and peptide drugs are listed along with their formulations and medical applications. The conclusion emphasizes that protein and peptide drugs will replace many existing pharmaceuticals, posing a challenge to develop viable delivery systems for non-parenteral administration.
Drug and gene delivery vehicles are biocompatible devices that can carry therapeutic components in the body. Synthetic vehicles include block copolymers, liposomes, dendrimers, and magnetic nanoparticles. Block copolymers form micelles with hydrophobic cores that can encapsulate drugs. Liposomes are phospholipid vesicles that can encapsulate both hydrophilic and hydrophobic drugs. Dendrimers are nanoscale polymers that can be functionalized to target drugs. Magnetic nanoparticles can be used for drug delivery, hyperthermia cancer treatment, and as MRI contrast agents. These vehicles aim to improve drug bioavailability and targeting while decreasing toxicity.
This document discusses protein and peptide drug delivery systems. It begins by defining proteins and peptides, and describing their structures. It then discusses various challenges in delivering protein and peptide drugs, such as stability issues like denaturation, aggregation, oxidation, and proteolysis. It also categorizes different drug delivery routes like parenteral, pulmonary, transdermal, and oral. Finally, it provides examples of marketed protein and peptide drug formulations and discusses strategies to improve stability and delivery of these drugs.
Biotransformation, or metabolism, refers to the chemical alteration of drugs in the body. The primary site is the liver, where drugs undergo two main phases of metabolism - phase I and phase II reactions. Phase I reactions like oxidation and hydrolysis functionally alter drugs, while phase II or conjugation reactions make drugs more polar and excretable by conjugating them to other molecules. Many drugs are activated or inactivated in these metabolic pathways. Metabolism can occur in other tissues as well and is mediated by various enzyme systems like the cytochrome P450 enzymes. Drug metabolism can be inhibited or induced, affecting the activity of other drugs a patient may be taking.
Protein and peptide are biopolymers which yield more than two amino acids on hydrolysis.
Although the terms ‘proteins’ and ‘peptides’ are used freely, peptides are those with molecular weight below 10,000 and proteins are molecules with higher molecular weight.
Most therapeutic proteins and peptide-based drugs are administered by parenteral route and are incorporated in liposomes to prolong their action or fused with Immunoglobulins or Albumin to improve their half-life.
PEGylation is a proven technique for improving the potentials of Proteins/peptide delivery systems.
ANTIOXIDANT ACTIVITY AND HEPATOPROTECTIVE EFFECTOF POMEGRANATE PEEL AND WHEY...Anurag Raghuvanshi
The antioxidant activity of pomegranate peel powder (PPP) and whey powder (WP) was evaluated, their hepatoprotective effect of each alone or in combination (PPWP) at equal levels was also evaluated in Wistar rats against carbon tetrachloride (CCL4) induced liver injury.
The hepatoprotective activity was assessed using various biochemical parameters and histopathological studies.
PLGA is a biodegradable and biocompatible copolymer of PLA and PGA that is widely used for controlled drug delivery. It can be synthesized via melt polycondensation or ring opening polymerization to produce copolymers of varying molecular weight and properties. PLGA nanoparticles are effectively used to encapsulate drugs and provide sustained release over time. The drug release kinetics from PLGA nanoparticles are dependent on factors like polymer composition, drug loading, particle size and shape. PLGA degrades via hydrolysis of its ester linkages into biocompatible monomers. Alpha-1 antitrypsin encapsulated in PLGA nanoparticles is a promising approach for pulmonary delivery to treat lung diseases.
This document discusses biotransformation, or the metabolism, of drugs in the body. It defines biotransformation as the chemical conversion of drugs from one form to another. The major organs involved in drug metabolism are the liver, lungs, kidneys, intestine, and placenta. The enzymes responsible for drug metabolism are divided into microsomal and non-microsomal enzymes. Drug metabolism occurs in two phases - phase I involves processes like oxidation and hydrolysis, while phase II involves conjugation reactions like glucuronidation and sulfation. Factors like the drug's physicochemical properties, genetic factors, age, and diet can influence a drug's metabolism in the body.
This document discusses proteins and peptides, their structures and functions. It provides examples of proteins and peptides used for various purposes like erythropoietin for red blood cell production and insulin for maintaining blood sugar levels. It then discusses challenges with oral delivery of proteins and peptides like degradation in the gastrointestinal tract. Various approaches to overcome these challenges are described, such as modifying the peptide structure, adding lipid chains to increase permeability, and using enzyme inhibitors and absorption enhancers. Specific examples of formulations using these approaches are also provided.
Protein and peptides drug delivery systemsVINOTH R
This document provides an overview of protein and peptide drug delivery. It discusses the structure of proteins and peptides, which consist of amino acids linked by peptide bonds. Various drug delivery techniques for proteins are described, including polymer, liposome, hydrogel, and emulsion-based systems. Challenges in delivering proteins include instability, degradation, and poor absorption. The document also discusses pumps, barriers to delivery, manufacturing, stability testing, instability issues, and some marketed protein and peptide drugs.
Practical consideration of protien and peptidesSuchandra03
This document summarizes a seminar on practical considerations for protein and peptide drug delivery. It begins with an introduction discussing the two main pathways of protein delivery research: non-invasive delivery methods and increasing drug half-life. It then covers the major barriers to protein delivery such as poor permeability, degradation, and stability issues. The document reviews protein structure, classification, properties, degradation pathways, and the rationale for protein drug delivery. It discusses various delivery strategies including chemical modifications, formulation vehicles, advancement like molecular conjugation and encapsulation, and considers toxicity, commercialization factors, and concludes discussing the challenges of oral protein delivery.
Pharmacokinetics and pharmacodynamics of protiens and peptidesSachinkumarBhairagon
This document discusses the pharmacokinetics and pharmacodynamics of proteins and peptides. It covers their administration pathways including injection, inhalation, and transdermal delivery. It describes their distribution throughout the body, with factors like protein binding and active transport processes affecting their volume of distribution. The document outlines their elimination, primarily through metabolism by proteases and peptidases in the gastrointestinal tract, liver, and kidneys, breaking them down into amino acids. It also briefly discusses pharmacodynamics, focusing on the drug-receptor interaction and subsequent physiological effects.
This document provides an overview of prodrug design and practical considerations. It defines prodrugs as chemically inert precursors that release the active pharmacological compound. Prodrugs are classified based on their carrier and linker groups. The rationale for prodrug design includes improving solubility, enhancing membrane permeability, reducing pre-systemic metabolism, and targeting delivery to specific sites. Practical considerations for prodrug design involve the use of ester, amide, phosphate and carbamate groups to link the drug. The document discusses several examples of prodrugs and their advantages over parent drugs.
This document discusses prodrugs, which are biologically inert derivatives of drug molecules that undergo conversion in vivo to release the active parent drug. Prodrugs can help overcome issues like poor solubility, stability, absorption and toxicity. They are designed to improve pharmaceutical, pharmacokinetic and pharmacodynamic properties. The concepts of carrier-linked prodrugs, mutual prodrugs, bioprecursor prodrugs and polymeric prodrugs are explained. The objectives of prodrug design like improving formulation, absorption and safety are covered. In conclusion, prodrug design is an important part of drug development that can enhance clinical effectiveness by overcoming undesirable properties.
This document provides an overview of metabolism and biotransformation. It defines key terms like metabolism, biotransformation, and xenobiotics. It describes the major sites of drug metabolism as the liver and secondary sites like the kidneys, lungs, and intestines. It outlines the two phases of biotransformation - phase I involving oxidation, reduction, and hydrolysis, and phase II involving conjugation reactions. Several examples of phase I and II enzyme systems and reactions are provided. The document also discusses enzyme induction and inhibition and their clinical importance in drug metabolism.
proteins are chains of amino acids, each joined to it
neighbor by a specific type of covalent bond. The
polymerization of L-α-amino acids by peptide
bonds forms the structural framework of proteins. The
term protein is used for molecules composed of over 50
amino acids. The term peptide is used for molecules
composed of less than 50 amino acids.
The chemical and structural complexities involved
demand an effective delivery system in which the
physicochemical and biologic properties, including
molecular size, conformational stability, solubility,
sensitivity to light, moisture and heat, biological half-life,
immunogenicity, dose requirements, susceptibility to
break down in both physical and biological environments,
requirement for specialized mechanisms for transport
across biological membranes are to be considered.
Peptide and Protein Structure
It is essential to have an idea about structure of protein
and peptide in order to deal with various problems
encountered while developing drug delivery system.
The proteins are relatively large molecules with complex
structure. The peptide chains in peptides and proteins are
seldom linear and adapt a variety of specific folded three
dimensional patterns and conformations.
All peptides and proteins are polymers of amino acids
connected via amide linkages referred to as peptide
bonds.
• Primary structure: It denotes the number and
specific sequence of amino acids.
• Secondary structure: Arrangement of individual
amino acids along the polypeptide backbone.
• Tertiary structure: Three dimensional
arrangement of a single protein molecule.
• Quaternary structure: Proteins that contain two
or more polypeptide chains associated by noncovalent
forces
Protein And Peptide Drug Delivery SystemKushal Saha
1) The document discusses protein and peptide drug delivery systems. It describes the structures of proteins, the need for effective delivery of proteins and peptides to overcome barriers like enzymatic degradation, and challenges like molecular size and stability.
2) Various delivery routes are covered including oral, buccal, nasal, pulmonary, transdermal and parental. Approaches to enhance delivery through each route like penetration enhancers, nanoparticles, and conjugates are summarized.
3) Key applications of protein and peptide drugs in cardiovascular, CNS, GI and immune systems are highlighted. Stability considerations like oxidation, deamination and hydrolysis are also discussed.
Clinical pharmacokintics part 2 dr jayesh vaghelajpv2212
This document discusses biotransformation and drug metabolism. It begins by introducing biotransformation as the biochemical transformation of drugs within living organisms catalyzed by enzymes. This allows insoluble compounds to become water soluble and be easily excreted. It then covers the phases of drug metabolism and the enzymes involved such as cytochrome P450 and discusses factors that can affect drug metabolism like age, sex, nutrition, and drug-drug interactions. Finally, it addresses the importance of understanding drug metabolism in the drug development process.
The document discusses three main topics:
1) How the number of hydroxyl groups on flavonols affects their binding affinity to serum albumin, with more hydroxyl groups increasing binding.
2) Glycosylation of flavonoids decreases their binding affinity to serum albumin by 1-3 orders of magnitude by introducing steric hindrance.
3) EGCG strongly binds to serum albumin and enhances the interaction of huperzine A, an acetylcholinesterase inhibitor, with serum albumin, potentially improving its transport and effects.
This document discusses plant-derived anticancer agents that are currently used in clinical practice or show promise as future treatments. It summarizes several prominent plant-derived compounds that are used clinically to treat various cancers, including vincristine, vinblastine, paclitaxel, camptothecin, and podophyllotoxin derivatives. It also outlines some challenges with developing plant-derived anticancer drugs and the process of isolating active compounds from plants and testing their efficacy and safety.
The document summarizes information about Scutellaria baicalensis and its primary active compound, baicalin. S. baicalensis has been used in traditional Chinese medicine to treat various conditions. Modern research indicates that baicalin has anti-cancer, anti-inflammatory, and antiviral properties. Baicalin is primarily extracted from S. baicalensis roots using heat reflux extraction or ultrasound-assisted extraction, with the latter providing higher yields in less time.
Potential plants molecule in cancer disease. The document discusses several herbal plants that show anticancer activity, including their mechanisms of action. It summarizes that Camptotheca acuminata contains camptothecin which inhibits topoisomerase I and DNA replication. Podophyllum contains podophyllotoxin and related compounds that inhibit topoisomerase II. Periwinkle contains alkaloids vinblastine and vincristine which prevent microtubule assembly. Taxus brevifolia contains taxol and related compounds that stabilize microtubules. Curcuma longa contains curcumin which has anti-inflammatory and apoptotic effects. Many herbal compounds show promise for cancer treatment but developing safe, economic anticancer drugs remains a
Cancer can be treated through natural products in addition to conventional treatments like surgery, chemotherapy, and radiation therapy. Natural products have anti-cancer properties and can help relieve cancer symptoms with fewer side effects than conventional treatments. Some promising natural products for cancer treatment discussed in the document include curcumin from turmeric, ellagic acid, green tea, and squalamine. Research is also exploring using peptides from natural sources to selectively target tumors. Both Western and Indian research is investigating using herbal extracts for cancer treatment and cure.
Studies that examined the therapeutic potential of plants leaf extracts
Plant Scientific Name Common Name Type of extraction Proposed active material
1. Solanum viarum Tropical Soda Apple Ether Solasodine glycoalkaloid
2. Acanthus illicifolious Harkucha Kanta Methanol Triterpenoids,Flavonoids,
Alkaloids
3. Annona squamosa Custard Apple Ethyl acetate Acetogenins,Alkaloids,
Dofamine
4 Alstonia scholaris. Chatium Methanol Alkaloids,Flavonoids
5. Calotropis gigantea Akanda Ethanol Triterpenoids,Flavonol
Glycosides
This document describes a molecular docking study examining lunacridine, scopoletin, and skimmianine from the Rutaceae plant family as potential inhibitors of the α-glucosidase enzyme. Docking results showed that all three compounds were able to bind to and inhibit α-glucosidase. Lunacridine exhibited the highest binding affinity and formed hydrogen bonds with two key amino acids. Pharmacokinetic analysis predicted good intestinal absorption for all compounds and compliance with Lipinski's rule of five, suggesting the ability to pass through cell membranes. Overall, lunacridine showed the most potential as an α-glucosidase inhibitor comparable to the control drug acarbose.
Preparation of protein-loaded PLGA-PVP blend nanoparticles by nanoprecipitati...Nanomedicine Journal (NMJ)
Abstract
Objective(s):
Despite of wide range applications of polymeric nanoparticles in protein delivery, there are some problems for the field of protein entrapment, initial burst and controlled release profile.
Materials and Methods:
In this study, we investigated the influence of some changes in PLGA nanoparticles formulation to improve the initial and controlled release profile. Selected parameters were: pluronic F127, polysorbate 80 as surfactant, pH of inner aqueous phase, L/G ratio of PLGA polymer, volume of inner aqueous phase and addition of polyvinylpyrrolidone as an excipient. FITC-HSA was used as a model hydrophilic drug. The nanoparticles were prepared by nanoprecipitation.
Results:
Initial release of FITC-HSA from PLGA-tween 80 nanoparticles (opt-4, 61%) was faster than control (PLGA-pluronic) after 2.30 h of incubation. Results showed that decrease in pH of inner aqueous phase to pI of protein can decrease IBR but the release profile of protein is the same as control. Release profile with three phases including a) initial burst b) plateau and c) final release phase was observed when we changed volume of inner aqueous phase and L/G ratio in formulation. Co-entrapment of HSA with PVP and pluronic reduced the IBR and controlled release profile in opt-19. Encapsulation efficiency was more than 97% and nanoparticles size and zeta potentials were mono-modal and -18.99 mV, respectively.
Conclusion:
In this research, we optimized a process for preparation of PLGA-PVP-pluronic nanoparticles of diameter less than 300 nm using nanoprecipitation method. This formulation showed a decreased initial burst and long lasting controlled release profile for FITC-HSA as a model drug for proteins.
Clopidogrel is a prodrug used to inhibit platelet aggregation. It requires hepatic metabolism to form its active metabolite. The metabolite binds irreversibly to the P2Y12 receptor on platelets to inhibit ADP-induced platelet activation and aggregation. Pharmacokinetic studies have found challenges in measuring clopidogrel and its active metabolite due to their instability and low plasma concentrations. Genetic polymorphisms of CYP enzymes involved in clopidogrel metabolism can affect its activation and antiplatelet effects.
Rational drug design begins by identifying a biological target implicated in disease. Drugs are then designed to modulate this target's activity in order to treat the disease. For a target to be suitable, there must be evidence it is disease-relevant and capable of binding small molecules. Once identified, the target is cloned, expressed, and purified. This allows high-throughput screening of chemical libraries to identify candidates that modify the target. Successful candidates should have properties predicting oral availability and low toxicity. Prodrugs and combinatorial chemistry are approaches that can improve drug properties and efficiency of discovery.
This document provides an overview of prodrugs. It begins with definitions, noting that a prodrug is a chemically modified inactive precursor that is metabolized in the body to release the active drug. The document then discusses the history of prodrugs, classifications including carrier-linked and bio-precursor prodrugs, and applications such as improving solubility, bioavailability, and site-specific drug delivery including targeting to the brain or colon. In summary, the document defines prodrugs, outlines their classifications and metabolic activation, and explores their applications in enhancing drug delivery and targeting.
Kaempferol increases levels of coenzyme Q in kidney cells and serves as a biosynthetic ring precursor
Complete study available in Free Radical Biology and Medicine. 2017 Sep;110:176-187.
doi: 10.1016/j.freeradbiomed.2017.06.006. Epub 2017 Jun 9.
This document discusses P-glycoprotein (P-gp), an ATP-dependent efflux pump found in the cell membranes of many tissues. P-gp pumps many foreign substances, drugs, and toxins out of cells. It plays an important physiological role and contributes to multidrug resistance in cancer cells by transporting chemotherapy drugs out of the cells. The document outlines the structure, mechanism of action, substrates, inhibitors, and approaches to bypassing P-gp efflux, such as using nanocarrier drug delivery systems.
This study investigated the gastroprotective effects of coenzyme Q10 (CoQ10) in indomethacin-induced gastric injury in rats and the role of matrix metalloproteinase 9 (MMP-9). Rats pretreated with CoQ10 before indomethacin showed significantly reduced gastric damage, increased prostaglandin E2 levels, and decreased MMP-9 and myeloperoxidase activities compared to rats given indomethacin alone. Pretreating rats with a nitric oxide inhibitor before CoQ10 attenuated the gastroprotective effect of CoQ10. The results suggest that regulation of MMP-9 is one mechanism of CoQ10's gastroprotective effect and that
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International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
In vitro and in vivo evaluation of positively charged liposaccharide derivati...Adel Abdelrahim, PhD
This document describes a study evaluating positively charged liposaccharide derivatives as oral absorption enhancers for delivering anionic drugs. Positively charged liposaccharide derivatives were synthesized and combined with the anionic model drug piperacillin through ion pairing. The conjugates were evaluated in vitro and in vivo to assess antimicrobial activity, plasma stability, permeability across Caco-2 cell monolayers, and oral absorption. Results showed that ion pairing the liposaccharide derivatives with piperacillin improved permeability in Caco-2 cells without altering antimicrobial activity, indicating potential as oral absorption enhancers.
This document discusses several potential drug-drug interactions involving various medications:
1. A woman taking simvastatin, diltiazem, aspirin is prescribed clarithromycin. Clarithromycin is a strong CYP3A4 inhibitor and may significantly increase simvastatin levels, increasing risk of side effects like rhabdomyolysis. The patient's simvastatin dose should not exceed 40 mg daily while taking clarithromycin.
2. Minocycline is unlikely to reduce the effectiveness of a low-dose combined oral contraceptive. Any interaction would be due to suppressed gut bacteria and is considered very rare.
3. A man's phenytoin levels increased after starting flu
International Journal of Clinical Pharmacology & Toxicology (IJCPT) ISSN:2167-910X is an Open Access journal, which aims to develop coherent means to modify drug therapy, with respect to the patient's genotype, and to ensure maximum efficiency with minimal contrary effects.
International Journal of Clinical Pharmacology & Toxicology (IJCPT) ISSN:2167-910X is an Open Access journal and a peer-reviewed journal. Clinical Pharmacology & Toxicology is the all-encompassing and becoming an increasingly important discipline for the identification of disease targets and drug designing with their toxicological effects and means to eradicate diseases.
Drug-Drug interactions (DDI) is a serious clinical issue. An important mechanism underlying of DDI, is
induction or inhibition of drug metabolizing enzymes (DMEs) and transporters that mediate metabolism, cellular uptake and efflux of xenobiotics. DDI cannot be avoided in many cases, as they belong to routine medical practice.
Bioanalytical support plays a vital role during the lead optimization stages. The major goal of the bioanalysis is to assess the over-all ADME characteristics of the NCEs and biologics. Bioanalytical tools can play a significant role and impact the progress in drug discovery and development. Dramatic increases in investments in new modalities beyond traditional small and large molecule drugs, such as peptides, oligonucleotides, and ADC, necessitated further innovations in bioanalytical and experimental tools for the characterization of their ADME and PK properties.https://www.medicilon.com/blog/featured-stories/dmpk-bioanalysis/
This research article investigates the effects of the natural flavonoid luteolin on colon cancer cells. The researchers found that physiological concentrations of luteolin induce apoptosis in colon cancer cells by increasing levels of the sphingolipid ceramide. Luteolin inhibits the conversion of ceramide to more complex sphingolipids and disrupts the transport of ceramide between organelles. These effects are mediated by luteolin's ability to inhibit the enzymes sphingosine kinase 2 and Akt, thereby reducing levels of the molecule sphingosine-1-phosphate which normally promotes cell survival. Overall, the study reveals that luteolin exerts anticancer effects by targeting the balance between ceramide and sphingosine-1-
Bryophyllum Pinnatum: A Potential Attenuator of Cadmium-Induced Oxidative Str...IOSR Journals
Cadmium has been famously implicated in the stimulation of free radical production in biosystems resulting in oxidative deterioration of lipids, proteins and DNA, and initiating various pathological conditions in humans and animals. This study therefore, examined the antidotal and ameliorative capacity of crude ethanolic extract of Bryophyllum pinnatum on cadmium-induced oxidative stress using rabbit models. A total of fifteen rabbits (1.30±0.05kg) were used for the study. After two weeks of acclimatization, the rabbits were randomly rifted into three experimental groups- (N, CD & CB) with five animals per group. The control group (N) was injected normal saline intraperitoneally (3mg/kg body weight) and the test groups (CD & CB) were administered cadmium once daily by subcutaneous injection (3mg/kg body weight). The ethanolic extract of the plant was orally administered once daily at a dose of 100mg/kg body weight. The oxidative and antioxidative stress parameters were assessed in tissues. The results showed significant difference (p˂ 0.05)in treated groups relative to the control group with the exception of glutathione peroxidase activity in leg muscles. Therefore, the results obtained in this study confirmed the potency of the plant to annihilate cadmium toxicity in animals
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Colloids and Surfaces B: Biointerfaces 101 (2013) 353– 360
Contents lists available at SciVerse ScienceDirect
Colloids and Surfaces B: Biointerfaces
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c o l s u r f b
harmacokinetics of curcumin-loaded PLGA and PLGA–PEG blend nanoparticles
fter oral administration in rats
ajeh Maissar Khalil , Thuane Castro Frabel do Nascimento , Diani Meza Casa , Luciana Facco Dalmolin ,
na Cristina de Mattos, Ivonete Hoss, Marco Aurélio Romano, Rubiana Mara Mainardes ∗
epartment of Pharmacy, Universidade Estadual do Centro-Oeste/UNICENTRO, Rua Simeão Camargo Varela de Sá 03, 85040-080 Guarapuava, PR, Brazil
r t i c l e i n f o
rticle history:
eceived 2 March 2012
eceived in revised form 10 June 2012
ccepted 12 June 2012
vailable online 28 June 2012
eywords:
urcumin
C–MS/MS
ioavailability
anoparticles
a b s t r a c t
The aim of this study was to assess the potential of nanoparticles to improve the pharmacokinetics of
curcumin, with a primary goal of enhancing its bioavailability. Polylactic-co-glycolic acid (PLGA) and
PLGA–polyethylene glycol (PEG) (PLGA–PEG) blend nanoparticles containing curcumin were obtained
by a single-emulsion solvent-evaporation technique, resulting in particles size smaller than 200 nm. The
encapsulation efficiency was over 70% for both formulations. The in vitro release study showed that cur-
cumin was released more slowly from the PLGA nanoparticles than from the PLGA–PEG nanoparticles. A
LC–MS/MS method was developed and validated to quantify curcumin in rat plasma. The nanoparticles
were orally administered at a single dose in rats, and the pharmacokinetic parameters were evaluated
and compared with the curcumin aqueous suspension. It was observed that both nanoparticles formu-
lations were able to sustain the curcumin delivery over time, but greater efficiency was obtained with
the PLGA–PEG nanoparticles, which showed better results in all of the pharmacokinetic parameters ana-
lyzed. The PLGA and PLGA–PEG nanoparticles increased the curcumin mean half-life in approximately 4
and 6 h, respectively, and the Cmax of curcumin increased 2.9- and 7.4-fold, respectively. The distribution
and metabolism of curcumin decreased when it was carried by nanoparticles, particularly PLGA–PEG
nanoparticles. The bioavailability of curcumin-loaded PLGA–PEG nanoparticles was 3.5-fold greater than
the curcumin from PLGA nanoparticles. Compared to the curcumin aqueous suspension, the PLGA and
PLGA–PEG nanoparticles increased the curcumin bioavailability by 15.6- and 55.4-fold, respectively.
These results suggest that PLGA and, in particular, P.
Metabolism,Excretion,prodrug,Therapeutic Drug monitoringSrinivasSree11
1. Metabolism and excretion are important processes that determine the duration and intensity of a drug's effects in the body. Metabolism involves chemical alteration of drugs through phase I and phase II reactions, while excretion removes drugs and metabolites from the body through renal, hepatic, pulmonary and other routes.
2. Factors like age, diet, diseases, genetic factors and simultaneous administration of other drugs can influence drug metabolism by inducing or inhibiting drug-metabolizing enzymes. Metabolism can convert drugs to active, inactive or less active forms.
3. Prodrugs are inactive forms administered to deliver the active drug selectively or improve pharmacokinetics. They are converted to active drugs through metabolic processes
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...Oleg Kshivets
Overall life span (LS) was 1671.7±1721.6 days and cumulative 5YS reached 62.4%, 10 years – 50.4%, 20 years – 44.6%. 94 LCP lived more than 5 years without cancer (LS=2958.6±1723.6 days), 22 – more than 10 years (LS=5571±1841.8 days). 67 LCP died because of LC (LS=471.9±344 days). AT significantly improved 5YS (68% vs. 53.7%) (P=0.028 by log-rank test). Cox modeling displayed that 5YS of LCP significantly depended on: N0-N12, T3-4, blood cell circuit, cell ratio factors (ratio between cancer cells-CC and blood cells subpopulations), LC cell dynamics, recalcification time, heparin tolerance, prothrombin index, protein, AT, procedure type (P=0.000-0.031). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and N0-12 (rank=1), thrombocytes/CC (rank=2), segmented neutrophils/CC (3), eosinophils/CC (4), erythrocytes/CC (5), healthy cells/CC (6), lymphocytes/CC (7), stick neutrophils/CC (8), leucocytes/CC (9), monocytes/CC (10). Correct prediction of 5YS was 100% by neural networks computing (error=0.000; area under ROC curve=1.0).
Histololgy of Female Reproductive System.pptxAyeshaZaid1
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.
Osteoporosis - Definition , Evaluation and Management .pdfJim Jacob Roy
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
share - Lions, tigers, AI and health misinformation, oh my!.pptxTina Purnat
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2. Effects of baicalein on nimodipine pharmacokinetics
Young-Ah Cho et al.
stitute up to 20% of the dry weight of S. radix [25,
Introduction
32]. After digestion, the glucuronides are readily hy-
drolyzed by intestinal bacteria [18]. Baicalein and re-
lated flavonoids are the major components responsible
Nimodipine is a dihydropyridine calcium channel
for the pharmacological effects of S. radix [16, 20].
blocker that has been shown to selectively dilate cere-
Baicalein inhibits the testosterone 6b-hydroxyl-
bral arteries and increase cerebral blood flow in ani-
ation activity of CYP3A4 and can also inhibit P-gly-
mals and humans [12]. Its major therapeutic indica-
coprotein in the multidrug resistant (TB/MDR) cell
tion is for the prevention and treatment of delayed
system [15], but the inhibitory effect of baicalein on
ischemic neurological disorders that often occur in
CYP3A4 and P-glycoprotein is partially ambiguous.
patients with subarachnoid hemorrhages [7, 27]. Ni-
Thus, we reevaluated CYP3A4 and P-glycoprotein
modipine is rapidly absorbed after oral administration activity using the rhodamine-123 retention assay in
and is widely distributed throughout the body. Orally the adriamycin-resistant human breast cancer cell line
administered nimodipine undergoes an extensive (MCF-7/ADR) overexpressing P-glycoprotein. The
first-pass hepatic metabolism from the portal circula- effect of baicalein was similar to that of quercetin [13]
tion, resulting in a low systemic bioavailability [19, and morin [2]. There are a few interactions between
30]. Usually only the parent compound is active and flavonoids and nimodipine [2]. However, little infor-
most of the metabolic steps involve reactions cata- mation is available regarding the in vivo effects of
lyzed by cytochrome P450 (CYP) enzymes. CYP en- these flavonoids on the pharmacokinetics of nimodip-
zymes have been shown to catalyze pyridine forma- ine. Baicalein and nimodipine could be prescribed as
tion, methyl hydroxylation, and various modes of a combination therapy [21]. Therefore, the aim of this
side-chain oxidation [23, 26]. study was to examine the effects of the antioxidant
The reduced bioavailability of nimodipine after oral ad- baicalein on CYP3A4 and P-glycoprotein activity on
ministration orally might not only be due to the metaboliz- the pharmacokinetics of nimodipine after oral admini-
ing enzyme CYP3A4 but also to the P-glycoprotein ef- stration of baicalein in rats.
flux transporter in the small intestine. Saeki et al. [24]
reported that nimodipine is a substrate for P-glyco-
protein-driven efflux, and Wacher et al. [33] reported
that nimodipine is a substrate for both CYP3A4 and
P-glycoprotein. P-glycoprotein is found in the secre- Materials and Methods
tory epithelial tissues, including the brush border of
the renal proximal tubules, the canalicular membranes Materials
in the liver and the apical membranes lining the gut.
In the small intestine, P-glycoprotein and CYP3A4 Nimodipine, nitrendipine (internal standard) and bai-
co-localize at the apical membrane of cells [9]. P-gly- calein were purchased from Sigma Chemical Co. (St.
coprotein and CYP3A4 may act synergistically during Louis, MO, USA). Ethyl acetate and methanol were
presystemic drug metabolism to cause the substrate of purchased from Merck Co. (Darmstadt, Germany). All
P-glycoprotein to move between the lumen and other chemicals were reagent grade and were used
epithelial cells, leading to prolonged exposure to without further purification. The apparatuses used in-
CYP3A4 and therby a reduced absorption of the drug cluded HPLC (Model LC-10A, Shimadzu Co., Kyoto,
[8, 10, 33, 34]. Japan), a syringe pump (Model341B, Sage Co., Kyoto,
Flavonoids are phytochemicals produced in high Japan), a vortex mixer (Scientific Industries, Seoul,
quantities by various plants [6]. These compounds ex- Korea) and a centrifuge (Abbot Co., TM, USA).
hibit a wide range of beneficial biological activities
including antioxidative, radical scavenging, antiathe- Animal experiments
rosclerotic, antitumor and antiviral effects [21]. Fla-
vonoids also modulate the CYP3A subfamily and/or Male Sprague-Dawley rats weighing 270–300 g were
P-glycoprotein [1, 5, 14]. Baicalein is the major fla- purchased from the Dae Han Laboratory Animal Re-
vonoid in Scutellariae radix and is mainly present in search Co. (Choongbuk, Korea) and were given ac-
its glucuronide form. Baicalein glucuronides can con- cess to a commercial rat chow diet (No. 322-7-1, Su-
Pharmacological Reports, 2011, 63, 1066–1073 1067
3. perfeed Co., Gangwon, Korea) and tap water. The ani- The HPLC system consisted of two solvent deliv-
mals were housed two per cage and maintained at ery pumps (Model LC-10AD, Shimadzu Co., Japan),
22 ± 2°C and 50–60% relative humidity under a 12:12 a UV detector (Model SPD-10A), a system controller
h light-dark cycle. The experiments were initiated af- (Model SCL-10A), a degasser (Model DGU-12A) and
ter acclimation under these conditions for at least an auto injector (SIL-10AD). The UV detector was set
1-week. The Animal Care Committee of Chosun Uni- at a wavelength of 310 nm. The stationary phase was
versity (Gwangju, Korea) approved the design and a Hypersil ODS column (5 µm, 4.6 × 150 mm). The
conduction of this study. The rats fasted for at least mobile phase consisted of methanol and water (65:35,
24 h prior to the experiments, and each animal was v/v). The mobile phase was filtered by passage
anesthetized lightly with diethyl ether. The left femo- through a 0.45-µm pore size membrane filter. The re-
ral artery and vein were cannulated using polyethyl- tention times at a flow rate of 1.0 ml/min were as fol-
ene tubing (SP45, i.d. 0.58 mm, o.d. 0.96 mm; Nat- lows: internal standard, 7.6 min; nimodipine, 9.1 min.
sume Seisakusho Co. LTD., Tokyo, Japan) for blood Linear regression analysis using a least-square fit was
sampling and intravenous injection, respectively. performed. The calibration curve was obtained from
the standard samples at 10, 20, 50, 100, 500, and
1,000 ng/ml. The regression equation obtained was
Drug administration
y = 206.0x + 18.1 (r = 0.999). The limit of detection
(LOD) of nimodipine in rat’s plasma was 3.3 ng/ml
The rats were divided into four groups (n = 6): an oral
(S/N ratio = 3). The coefficients of variation for nimo-
control group (12 mg/kg of nimodipine dissolved in
dipine were below 12.5%.
distilled water, 3.0 ml/kg) with or without 0.4, 2 and
8 mg/kg of baicalein (mixed in distilled water, 3.0 ml/
CYP3A4 inhibition assay
kg), and an intravenous (iv) group (3 mg/kg of nimo-
dipine, dissolved in 0.9% NaCl solution, 1.5 ml/kg).
To assay the inhibition of human CYP3A4 enzyme
Oral nimodipine was administered intragastrically us-
activity, a CYP inhibition assay kit (GENTEST,
ing a feeding tube, and baicalein was administered in
Woburn, MA) was used in a multiwell plate as
the same manner 30 min prior to the oral administra-
described previously [3]. Briefly, human CYP was
tion of nimodipine. Nimodipine for iv administration
obtained from baculovirus-infected insect cells. The
was injected through the femoral vein within 0.5 min.
CYP substrate 7-benzyloxy-4-trifluoromethylcoumarin
A 0.4 ml of blood was collected into heparinized
(BFC) was incubated with or without test compounds
tubes from the femoral artery at 0 (to serve as con-
in the buffer containing enzyme and substrate with
trol), 0.25, 0.5, 1, 2, 3, 4, 8, 12, 24 and 36 h after ni-
1 pmol of P450 enzyme and an NADPH-generating sys-
modipine administration. The blood samples were
tem (1.3 mM NADP, 3.54 mM glucose 6-phosphate,
centrifuged at 16,800 × g for 5 min, and the plasma
0.4 U/ml glucose 6-phosphate dehydrogenase and
samples were stored at –40°C until HPLC analysis.
3.3 mM MgCl2) in a potassium phosphate buffer (pH
7.4). Reactions were terminated by adding stop solu-
HPLC assay tion after a 45-min incubation. Metabolite concentra-
tions were measured by spectrofluorometry (Molecular
The plasma nimodipine concentration was determined Device, Sunnyvale, CA) at an excitation wavelength of
by an HPLC assay using a modification of the method 409 nm and an emission wavelength of 530 nm. The
reported by Qian et al. [22]. Briefly, 50 µl of nitren- positive control (1 µM ketoconazole for CYP3A4) was
dipine (1 µg/ml) as the internal standard and 50 µl of run on the same plate and produced 99% inhibition. All
ethyl acetate were added to 0.2 ml of the plasma sam- experiments were conducted in duplicate, and the re-
ples. The mixture was stirred for 10 min and centri- sults are expressed as the percent of inhibition.
fuged at 3,000 rpm for 10 min. Next, 5 ml of the or-
ganic layer was transferred to a clean test tube and Rhodamine-123 retention assay
evaporated at 40°C under a stream of nitrogen. The
residue was then dissolved in 300 µl of 65% metha- MCF-7/ADR cells were seeded in 24-well plates. At
nol, centrifuged at 3,000 rpm for 10 min, and 50 µl of 80% confluence, the cells were incubated in fetal bo-
the solution was injected into the HPLC system. vine serum (FBS)-free Dulbecco’s modified Eagle’s
1068 Pharmacological Reports, 2011, 63, 1066–1073
4. Effects of baicalein on nimodipine pharmacokinetics
Young-Ah Cho et al.
medium (DMEM) for 18 h. The culture medium was
Results
changed to Hanks’ balanced salt solution and the cells
were incubated at 37°C for 30 min. After incubation of
the cells with 20 µM rhodamine-123 in the presence or Inhibition of CYP3A4
absence of baicalein (1, 3 and 10 µM) for 90 min, the
The inhibitory effect of baicalein on CYP3A4 activity
medium was completely removed. The cells were
is shown in Figure 1. Baicalein inhibited CYP3A4 ac-
then washed three times with ice-cold phosphate
tivity in a concentration-dependent manner. Baicalein
buffer (pH 7.0) and lysed in EBC lysis buffer.
inhibited human CYP3A4 with a 50% inhibition con-
Rhodamine-123 fluorescence in the cell lysates was
centration (IC50) value of 9.2 µM.
measured using excitation and emission wavelengths
of 480 and 540 nm, respectively. Fluorescence values
Rhodamine-123 retention assay
were normalized to the total protein content of each
sample and are presented as the ratio to control. The accumulation of rhodamine-123, a P-glycoprotein
substrate, in MCF-7/ADR cells overexpressing P-gly-
coprotein was greater than that of MCF-7 cells lack-
Pharmacokinetic analysis
ing P-glycoprotein, as shown in Figure 2. The concur-
rent use of baicalein enhanced the cellular uptake of
The plasma concentration data were analyzed using rhodamine-123 in a concentration-dependent manner
a non-compartmental method from WinNonlin soft- ranging from 1 to 10 µM. This result suggests that
ware, version 4.1 (Pharsight Co., Mountain View, CA, baicalein significantly (p < 0.05 and p < 0.01) inhib-
USA). The elimination rate constant (Kel) was calcu- ited P-glycoprotein activity.
lated using the log-linear regression of nimodipine con-
centration data during the elimination phase, and the
terminal half-life (t1/2) was calculated by 0.693/Kel. The
peak concentration (Cmax) and time to reach the peak
concentration (Tmax) of nimodipine in the plasma were
obtained by a visual inspection of the data from the
concentration-time curve. The area under the plasma
concentration-time curve (AUC0–t) from time zero to
the time of the last-measured concentration (Clast) was
calculated using the linear trapezoidal rule. The AUC
zero to infinity (AUC0–¥) was obtained by adding
AUC0–t, and the extrapolated area was calculated by
Clast/Kel. The total body clearance for the iv route (CLt)
was calculated as D/AUC, where D is the dose of ni-
modipine. The absolute bioavailability (AB) of nimo-
dipine was calculated by AUCoral/AUCiv × Doseiv/
Doseoral × 100; the relative bioavailability (RB) was
calculated as (AUCcontrol/AUCwith baicalein) × 100.
Statistical analysis
Fig. 1. The inhibitory effect of baicalein on CYP3A4 activity. The CYP
All data are presented the mean with standard devia- substrate 7-BFC was incubated with or without test compounds in
the enzyme/substrate mixture. Reactions were terminated by adding
tion. The analysis of variance (ANOVA) with Schef- stop solution after a 45-min incubation. Metabolite concentrations
were measured by spectrofluorometry with excitation and emission
fe’s test was used to determine significant differences wavelengths of 409 and 530 nm, respectively. The positive control
between the control groups and co-administration or (1 µM ketoconazole for CYP3A4) was run on the same plate and pro-
duced 99% inhibition. All experiments were conducted in duplicate,
pretreatment groups. A p value < 0.05 was considered and the results are expressed as the percent of inhibition (IC50:
significant. 9.2 µM)
Pharmacological Reports, 2011, 63, 1066–1073 1069
5. uptake
Fig. 2. Rhodamine-123 retention. MCF-7/ADR cells were incubated
in FBS-free DMEM for 18 h and then with 20 µM rhodamine-123 in the
presence or absence of baicalein (1, 3 and 10 µM) for 90 min.
Rhodamine-123 fluorescence in the cell lysates was measured using Fig. 3. Mean plasma concentration-time profiles of nimodipine after
excitation and emission wavelengths of 480 and 540 nm, respec- the oral co-administration of nimodipine (12 mg/kg) and baicalein to
tively. The values were divided by the total protein contents of each rats. (l) Nimodipine control, (o) with 0.4 mg/kg baicalein, (q) with
sample. Data are represented as the mean ± SD (n = 6). * p < 0.05, 2 mg/kg baicalein, (<) with 8 mg/kg baicalein. Bars represent the
** p < 0.01, significant difference compared to control MCF-7 cells standard deviation (n = 6)
ine. Compared to the control group given oral nimodip-
Effect of baicalein on the pharmacokinetics of
oral nimodipine ine alone, baicalein significantly (p < 0.05 for 2 mg/kg;
p < 0.01 for 8 mg/kg) increased the area under the
The mean arterial plasma concentration-time profiles plasma concentration-time curve (AUC0–¥) and the peak
of nimodipine following an oral administration of ni- plasma concentration (Cmax) of nimodipine. Baicalein
modipine (12 mg/kg) to rats in the presence or ab- also significantly (p < 0.05 for 2 mg/kg; p < 0.01 for
sence of baicalein (0.4, 2 and 8 mg/kg) are shown in 8 mg/kg) increased the absolute bioavailability (AB) of
Figure 3, and the corresponding pharmacokinetic pa- nimodipine by 31.0–35.5% compared to the oral control
rameters are shown in Table 1. Baicalein significantly group (22.3%), and the relative bioavailability (RB) of
altered the pharmacokinetic parameters of nimodip- nimodipine was increased by 1.39- to 1.58-fold.
Tab. 1. Mean pharmacokinetic parameters of nimodipine after the oral administration of nimodipine (12 mg/kg) to rats with baicalein (0.4, 2 and
8 mg/kg)
Parameter Control Nimodipine with baicalein
0.4 mg/kg 2 mg/kg 8 mg/kg
AUC0–¥ (ng¡ ´ h/ml) 509 ± 112 587 ± 126 706 ± 165* 805 ± 178**
Cmax (ng/ml) 91 ± 16 95 ± 22 113 ± 17* 123 ± 25*
Tmax (h) 0.25 0.25 0.25 0.25
T1/2 (h) 7.4 ± 1.6 7.8 ± 1.9 8.2 ± 2.1 8.4 ± 2.3
AB (%) 22.3 ± 4.7 25.7 ± 5.9 31.0 ± 6.6* 35.3 ± 7.8**
RB (%) 100 115 139 158
The mean ± SD (n = 6), * p < 0.05, ** p < 0.01, significant difference compared to control, AUC0–¥ – area under the plasma concentration- time
curve from 0 h to infinity; Cmax – peak plasma concentration; Tmax – time to reach Cmax; T1/2 – terminal half-life; AB – absolute bioavailability; RB –
relative bioavailability
1070 Pharmacological Reports, 2011, 63, 1066–1073
6. Effects of baicalein on nimodipine pharmacokinetics
Young-Ah Cho et al.
were not affected by the concurrent use of baicalein in
contrast to those of oral nimodipine. Accordingly, the
enhanced oral bioavailability in the presence of bai-
calein without a significant change in the pharmacoki-
netics of intravenous nimodipine may be mainly due
to the inhibition of CYP3A-mediated metabolism of
nimodipine in the small intestine and/or in the liver
and to the inhibition of the P-glycoprotein efflux
pump in the small intestine by baicalein, rather than
renal elimination of nimodipine.
Discussion
Fig. 4. Mean plasma concentration-time profiles of nimodipine after
iv administration of nimodipine (3 mg/kg) and baicalein to rats. (l) Ni-
Based on the broad overlap in substrate specificities
modipine control, (o) with 0.4 mg/kg baicalein, (q) with 2 mg/kg bai- and the co-localization in the small intestine, the pri-
calein, (<) with 8 mg/kg baicalein. Bars represent the standard de-
viation (n = 6) mary site of absorption for orally administered drugs,
CYP3A4 and P-glycoprotein are recognized as a bar-
rier to drug absorption [4, 35]. CYP enzymes signifi-
cantly contribute to first-pass metabolism and oral
bioavailability. Moreover, induction or inhibition of
Effect of baicalein on the pharmacokinetics intestinal CYP enzymes may be responsible for sig-
of iv nimodipine nificant drug-drug interactions [17], in which one
agent decreases or increases the bioavailability and
The mean arterial plasma concentration-time profiles absorption rate constant of another drug administered
of nimodipine following an intravenous administra- concurrently [11]. Therefore, dual inhibitors against
tion of nimodipine (3 mg/kg) to rats in the presence or both CYP3A4 and P-glycoprotein should have a great
absence of baicalein (0.4, 2 and 8 mg/kg) are shown impact on the bioavailability of many drugs for which
in Figure 4, and the corresponding pharmacokinetic CYP3A4 metabolism and P-glycoprotein mediated
parameters are shown in Table 2. The AUC of nimo- efflux are the major barriers to systemic availability.
dipine increased but was not statistically different With the great interest in herbal components as alterna-
than the iv control group. The T1/2 of nimodipine was tive medicines, much effort is currently being expended
also prolonged, but this increase was not significant. to identify natural compounds of plant origin that modu-
The pharmacokinetics of intravenous nimodipine late P-glycoprotein and metabolic enzymes. However,
Tab. 2. Mean pharmacokinetic parameters of nimodipine after iv administration of nimodipine (3 mg/kg) to rats with baicalein (0.4, 2 and
8 mg/kg)
Parameter Control Nimodipine with baicalein
0.4 mg/kg 2 mg/kg 8 mg/kg
AUC0–¥ (ng¡ ´ h/ml) 570 ± 118 605 ± 127 641 ± 131 675 ± 137
CLt (ml/h/kg) 87 ± 18 82 ± 17 78 ± 16 74 ± 15
T1/2 (h) 6.5 ± 1.3 6.7 ± 1.4 7.1 ± 1.5 7.2 ± 1.5
RB 100 106 112 118
The mean ± SD (n = 6), AUC0–¥ – area under the plasma concentration-time curve from 0 h to infinity; CLt – total body clearance; T1/2 – terminal
half-life; RB – relative bioavailability
Pharmacological Reports, 2011, 63, 1066–1073 1071
7. there is less information on the pharmacokinetic inter- in reduced intestinal or hepatic first-pass metabolism.
actions between herbal components and medicines. These results are consistent with a report by Choi et al.
More preclinical and clinical investigations on the in- [2], which showed that morin significantly increased
teractions between herbal constituents and drugs the AUC0–¥ and Cmax of nimodipine, a P-glycoprotein
should be performed to prevent potential adverse re- and CYP3A4 substrate, and a report by Shin et al. [28],
actions in patients or to utilize those interactions for which showed that baicalein significantly increased the
a therapeutic benefit. To this end, the present study AUC0–¥ and bioavailability of doxorubin in rats.
evaluated the effect of baicalein, a naturally occurring Baicalein significantly enhanced the oral bioavail-
flavonoid, on the pharmacokinetics of nimodipine in ability of nimodipine, which might be primarily at-
rats to examine a potential drug interaction between tributable to the promotion of intestinal absorption
baicalein and nimodipine via the dual inhibition of and the reduction of first-pass metabolism of nimo-
CYP3A4 and P-glycoprotein. dipine in the intestine and/or liver via inhibition of
Nimodipine is metabolized by CYP3A4 in both the P-glycoprotein and CYP3A4.
liver and small intestine [23, 26] and the absorption of
nimodipine in the intestinal mucosa is inhibited by the
P-glycoprotein efflux pump [24]. P-glycoprotein is ex-
pressed with the glutathione-S-transferases CYP3A4 Conclusion
[29, 31], which may play a synergistic function in
regulating the bioavailability of many orally ingested
Baicalein significantly enhanced the oral bioavailabil-
compounds. In the small intestine, P-glycoprotein
ity of nimodipine, which might be mainly due to the
co-localized with CYP3A4 at the apical membrane of
inhibition of CYP3A4-mediated metabolism of nimo-
cells [35]. P-glycoprotein and CYP3A4 might act syn-
dipine in the small intestine and/or in the liver and in-
ergistically to limit oral absorption and first-pass me-
hibition of the P-glycoprotein efflux pump in the
tabolism [32]. Therefore, CYP3A4 and P-glycoprotein
small intestine by baicalein, rather than the renal
inhibitors have the potential to alter the pharmacokinet-
elimination of nimodipine. The increase in oral bioa-
ics of nimodipine. The inhibitory effect of baicalein
vailability of nimodipine in the presence of baicalein
against CYP3A4-mediated metabolism was confirmed
should be taken into consideration as a potential drug
by the use of the recombinant CYP3A4 enzyme.
interactions between nimodipine and baicalein.
As shown in Figures 1 and 2, baicalein had an in-
hibitory effect against CYP3A4-mediated metabolism
and significantly inhibited P-glycoprotein activity.
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