Eicosanoids is the class of lipids derived from arachidonic acid. Eicosanoids play an important role in the growth and development, cellular signalling, drug response, platelet action and maintenance of body homeostasis.
Eicosanoids are 20-carbon compounds derived from polyunsaturated fatty acids like arachidonic acid that act as local hormones. They include prostaglandins, thromboxanes, and leukotrienes, which play important roles in inflammation and regulating other physiological processes. They are synthesized through the cyclooxygenase and lipoxygenase pathways and have short lifespans, being quickly degraded. Eicosanoids function through G-protein coupled cell surface receptors and though potent, also have diverse tissue-specific actions.
Eicosanoids are derived from omega-3 and omega-6 fatty acids and include prostaglandins, thromboxanes, and leukotrienes. Prostaglandins function in vasodilation, inducing labor pains, regulating inflammation and cell growth. Thromboxanes are involved in blood clot formation and platelet activation. Leukotrienes contribute to pathologies like asthma and dementia by promoting inflammation and bronchoconstriction. The three classes of eicosanoids serve important physiological roles through their diverse functions.
This document summarizes different classes of lipids, including eicosanoids, terpenoids, steroids, and phytosterols. It describes the structures and properties of prostaglandins, leukotrienes, lipoxins, terpenes, carotenoids, dolichol, coenzyme Q, cholesterol, bile acids, phytosterols like sitosterol and stigmasterol. Examples are provided of monoterpenes, sesquiterpenes, diterpenes, and tetraterpenes. The roles of these lipids in biological processes and potential applications are briefly mentioned.
This document discusses eicosanoids, a class of biologically active lipid compounds derived from 20-carbon polyunsaturated fatty acids like arachidonic acid. It describes the biosynthesis of eicosanoids via three main pathways (cyclooxygenase, lipoxygenase, cytochrome P450), their biological effects like inflammation and platelet aggregation, and examples of specific eicosanoids like prostaglandins, thromboxanes, leukotrienes, lipoxins, and hydroxyeicosatetraenoic acids.
This document discusses eicosanoids, a class of biologically active lipid compounds that includes prostaglandins and leukotrienes. It notes that most eicosanoids are produced from arachidonic acid and classified into prostanoids, leukotrienes, and lipoxins. The document provides details on the synthesis and functions of various prostaglandins and thromboxanes, including their role in inflammation, smooth muscle contraction, kidney function, and other physiological processes. It also summarizes the synthesis and functions of leukotrienes and lipoxins.
This document discusses eicosanoids, which are signaling molecules derived from fatty acids. Eicosanoids are classified into two main groups - prostanoids and leukotrienes/lipoxins. They are produced through the oxidation of fatty acids like arachidonic acid by enzymes like cyclooxygenase and lipoxygenase. Eicosanoids play important roles in inflammation and other bodily processes through their effects on systems like the cardiovascular and respiratory systems.
Prostaglandin, leukotriene, and thromboxaneGeeta Jaiswal
Eicosanoids are signaling molecules derived from polyunsaturated fatty acids like arachidonic acid. They are involved in complex control over inflammation, immunity, and the central nervous system. Eicosanoids are synthesized through the enzymatic oxidation of fatty acids by cyclooxygenase and lipoxygenase enzymes. They have short half-lives and act locally through autocrine and paracrine signaling. Examples of important eicosanoids include prostaglandins, thromboxanes, and leukotrienes.
Eicosanoids are 20-carbon compounds derived from polyunsaturated fatty acids like arachidonic acid that act as local hormones. They include prostaglandins, thromboxanes, and leukotrienes, which play important roles in inflammation and regulating other physiological processes. They are synthesized through the cyclooxygenase and lipoxygenase pathways and have short lifespans, being quickly degraded. Eicosanoids function through G-protein coupled cell surface receptors and though potent, also have diverse tissue-specific actions.
Eicosanoids are derived from omega-3 and omega-6 fatty acids and include prostaglandins, thromboxanes, and leukotrienes. Prostaglandins function in vasodilation, inducing labor pains, regulating inflammation and cell growth. Thromboxanes are involved in blood clot formation and platelet activation. Leukotrienes contribute to pathologies like asthma and dementia by promoting inflammation and bronchoconstriction. The three classes of eicosanoids serve important physiological roles through their diverse functions.
This document summarizes different classes of lipids, including eicosanoids, terpenoids, steroids, and phytosterols. It describes the structures and properties of prostaglandins, leukotrienes, lipoxins, terpenes, carotenoids, dolichol, coenzyme Q, cholesterol, bile acids, phytosterols like sitosterol and stigmasterol. Examples are provided of monoterpenes, sesquiterpenes, diterpenes, and tetraterpenes. The roles of these lipids in biological processes and potential applications are briefly mentioned.
This document discusses eicosanoids, a class of biologically active lipid compounds derived from 20-carbon polyunsaturated fatty acids like arachidonic acid. It describes the biosynthesis of eicosanoids via three main pathways (cyclooxygenase, lipoxygenase, cytochrome P450), their biological effects like inflammation and platelet aggregation, and examples of specific eicosanoids like prostaglandins, thromboxanes, leukotrienes, lipoxins, and hydroxyeicosatetraenoic acids.
This document discusses eicosanoids, a class of biologically active lipid compounds that includes prostaglandins and leukotrienes. It notes that most eicosanoids are produced from arachidonic acid and classified into prostanoids, leukotrienes, and lipoxins. The document provides details on the synthesis and functions of various prostaglandins and thromboxanes, including their role in inflammation, smooth muscle contraction, kidney function, and other physiological processes. It also summarizes the synthesis and functions of leukotrienes and lipoxins.
This document discusses eicosanoids, which are signaling molecules derived from fatty acids. Eicosanoids are classified into two main groups - prostanoids and leukotrienes/lipoxins. They are produced through the oxidation of fatty acids like arachidonic acid by enzymes like cyclooxygenase and lipoxygenase. Eicosanoids play important roles in inflammation and other bodily processes through their effects on systems like the cardiovascular and respiratory systems.
Prostaglandin, leukotriene, and thromboxaneGeeta Jaiswal
Eicosanoids are signaling molecules derived from polyunsaturated fatty acids like arachidonic acid. They are involved in complex control over inflammation, immunity, and the central nervous system. Eicosanoids are synthesized through the enzymatic oxidation of fatty acids by cyclooxygenase and lipoxygenase enzymes. They have short half-lives and act locally through autocrine and paracrine signaling. Examples of important eicosanoids include prostaglandins, thromboxanes, and leukotrienes.
The document discusses various topics related to metabolic regulation and integration. It describes how the liver, adipose tissue, muscle, and brain are important organs for fuel metabolism. It also summarizes the roles of insulin and glucagon in regulating metabolism. Insulin promotes anabolic processes like glycogen synthesis and fat storage, while glucagon stimulates catabolic processes like gluconeogenesis to increase blood glucose. The document also provides information on fuel storage in the body and the key roles of glucose-6-phosphate, pyruvate, and acetyl-CoA as junction points in metabolic pathways.
This document summarizes the biosynthesis, receptors, and pharmacological actions of eicosanoids including prostaglandins, thromboxanes, prostacyclins, and leukotrienes. It describes that these molecules are derived from arachidonic acid and produced via the cyclooxygenase and lipoxygenase pathways. The document outlines the different receptors for each eicosanoid class and their downstream signaling effects. It also provides details on the physiological and pathological roles of eicosanoids in various organ systems such as the cardiovascular, pulmonary, gastrointestinal, renal and immune systems.
This document discusses second messenger systems, which relay signals from cell surface receptors to target molecules inside cells. There are three major classes of second messenger systems: 1) the adenylyl cyclase-cAMP system, which is activated by hormones like epinephrine and glucagon and uses cAMP as the second messenger; 2) the phospholipid system, which uses IP3 and DAG as second messengers; and 3) the calcium-calmodulin system, where calcium acts as the second messenger and binds to and activates calmodulin. These second messengers amplify signals and allow hormones and neurotransmitters to trigger intracellular responses.
This document summarizes the glucuronic acid pathway, an alternative oxidative pathway for glucose metabolism. It provides UDP-glucuronic acid, which is used to conjugate bilirubin, steroids, and drugs to make them more water soluble and excretable. The pathway also synthesizes glycosaminoglycans and is involved in vitamin C synthesis in many animals. Key steps include the conversion of glucose-6-phosphate to UDP-glucuronate and the subsequent production of L-gulonate, a precursor for ascorbic acid synthesis. Certain genetic disorders can cause excess excretion of metabolites from this pathway such as L-xylulose in essential pentosuria.
This document outlines key hormones that regulate metabolic homeostasis, including insulin, glucagon, epinephrine, and cortisol. It describes their structure, biosynthesis, mechanisms of action, and metabolic effects. Insulin promotes anabolism and lowers blood glucose levels, while glucagon, epinephrine, and cortisol have catabolic effects and increase blood glucose as counterregulatory hormones opposed to insulin. Precise regulation of these hormones maintains stable blood glucose levels and fuels metabolism.
This document compares four main types of prostaglandins: PGI2, PGD2, PGE2, and PGF2α. PGI2 regulates cardiovascular homeostasis through vasodilation and platelet inhibition. PGD2 is involved in regulating sleep and pain perception in the brain and inflammation in tissues. PGE2 mediates immune responses and various physiological functions through different receptors. PGF2α derived from COX-1 plays roles in female reproduction and other processes such as renal function and inflammation.
Glycoproteins are proteins that contain carbohydrate chains covalently attached to their polypeptide side chains. They can be N-linked, O-linked, or GPI-linked. Glycoproteins serve many important functions including structure, protection, reproduction, hormones, and enzymes. Alterations in cell surface glycoproteins can impact physiology, for example certain viruses use cell surface glycoproteins to infect cells. I-cell disease results from a deficiency in an enzyme involved in glycoprotein targeting, leading to severe developmental and neurological issues.
- Glycoproteins are proteins that contain oligosaccharide chains covalently attached to their polypeptide backbones. They serve important biological roles.
- There are two main classes of glycoproteins: O-linked, where sugars attach to serine or threonine residues, and N-linked, where sugars attach to asparagine residues.
- Diseases can result from defects in glycoprotein biosynthesis, such as I-cell disease caused by a defect in N-linked glycosylation and congenital disorders of glycosylation caused by various defects impacting O-linked or N-linked glycosylation.
Prostaglandins are 20 carbon compounds derived from arachidonic acid. They are produced in various tissues and act as local hormones, regulating processes like blood pressure, reproduction, pain and fever. Examples include prostaglandin E2, D2, I2 and F2α. Prostaglandins have important biochemical actions and biomedical applications, such as treatment of ulcers, hypertension, asthma, and induction of labor.
Prostaglandins are locally-acting lipid mediators derived from arachidonic acid through the cyclooxygenase pathway. They have diverse hormone-like effects and are produced throughout the body, acting on nearby cells through G-protein coupled receptors. Prostaglandins have many functions including regulating inflammation, sensitizing neurons to pain, inducing labor, and vasodilation. They are different from true hormones as they act locally rather than at a distance and are synthesized as needed rather than being stored.
This presentation includes information about secretion of glucagon, inhibitors, regulation of secretion, mechanism of action & actions of glucagon. It also includes ways to prevention of occurrence of hyperglycemia.
1. The document discusses several hormones involved in regulating blood glucose levels, including insulin, glucagon, somatostatin, and pancreatic polypeptide.
2. Insulin decreases blood glucose levels, while glucagon and other hormones like growth hormone and cortisol increase blood glucose.
3. The liver plays an important role in maintaining blood glucose homeostasis by storing glucose as glycogen and releasing it as needed.
Second messengers are intracellular signaling molecules that are responsible for transmitting signals from hormones and neurotransmitters outside the cell to trigger physiological responses inside the cell. There are three main types of second messenger systems: cyclic nucleotides (cAMP and cGMP), phospholipid derivatives (IP3 and DAG), and calcium/calmodulin. Hormones activate G-protein coupled receptors which stimulate the production of cyclic nucleotides via adenylate cyclase or guanylate cyclase. Phospholipase C breaks down phospholipids to form IP3 and DAG. Calcium entry activates the calcium/calmodulin system. These second messengers go on to activate downstream effector proteins to elicit cellular responses.
GPCRs are the most dynamic and most abundant all the receptors. The G protein-coupled receptor (GPCR) superfamily comprises the largest and most diverse group of proteins in mammals. GPCRs are responsible for every aspect of human biology from vision, taste, sense of smell, sympathetic and parasympathetic nervous functions, metabolism, and immune regulation to reproduction. GPCRs interact with a number of ligands ranging from photons, ions, amino acids, odorants, pheromones, eicosanoids, neurotransmitters, peptides, proteins, and hormones.
Nevertheless, for the majority of GPCRs, the identity of their natural ligands is still unknown, hence remain orphan receptors.
The simple dogma that underpins much of our current understanding of GPCRs, namely,
one GPCR gene− one GPCR protein− one functional GPCR− one G protein −one response
is showing distinct signs of wear.
The document summarizes different mechanisms of hormone signal transduction. It describes how hormones bind to cell surface or intracellular receptors which then activate intracellular signaling pathways using second messengers like cAMP, IP3, DAG, calcium. These second messengers go on to affect cell functions like glycogen breakdown, lipid metabolism, transcription etc. through kinases and other effector proteins. The document also discusses G-protein coupled receptor pathway and steroid hormone signaling pathway involving hormone-receptor complexes in the cytoplasm and nucleus.
Glycogen is the storage form of carbohydrates in the human body, primarily in the liver and muscle. The liver stores glycogen to provide glucose to maintain blood sugar levels during periods of starvation. Muscle stores glycogen to act as a fuel reserve for muscle contraction, becoming depleted during prolonged exercise.
Proteoglycans are proteins that are heavily glycosylated*. The basic proteoglycan unit consists of a "core protein" with one or more covalently attached glycosaminoglycan (GAG) chain(s).
Dr. Pavani discusses G protein-coupled receptors (GPCRs), which are integral membrane proteins that sense molecules outside the cell and activate internal signal transduction pathways and cellular responses. There are over 800 GPCRs in humans that detect a wide range of ligands and are involved in many physiological processes. GPCRs work by coupling to G proteins, which activate various intracellular effectors like adenylyl cyclase, phospholipase C, and ion channels. Dysregulation of GPCR signaling can lead to many human diseases. Martin Rodbell and Alfred Gilman were awarded the 1994 Nobel Prize in Physiology or Medicine for their discoveries related to G proteins and GPCR signal transduction.
Eicosanoids mwisho.. For bettr understanding.pptxPharmTecM
The document discusses eicosanoids, which are signaling molecules derived from arachidonic acid that play roles in various physiological processes. There are three main types of eicosanoids: prostanoids, leukotrienes, and lipoxins. Prostanoids like prostaglandins and thromboxanes are derived from arachidonic acid via the cyclooxygenase pathway. Leukotrienes promote inflammation while lipoxins help resolve it. Eicosanoids act via specific receptors and are synthesized via cyclooxygenase and lipoxygenase enzymes acting on arachidonic acid. They are metabolized in the kidneys, lungs, and liver and play important roles in processes like
The principal eicosanoids of biological significance to humans are a group of molecules derived from the 20:4 (20 carbons: 4 sites of unsaturation) fatty acid, arachidonic acid.
The document discusses various topics related to metabolic regulation and integration. It describes how the liver, adipose tissue, muscle, and brain are important organs for fuel metabolism. It also summarizes the roles of insulin and glucagon in regulating metabolism. Insulin promotes anabolic processes like glycogen synthesis and fat storage, while glucagon stimulates catabolic processes like gluconeogenesis to increase blood glucose. The document also provides information on fuel storage in the body and the key roles of glucose-6-phosphate, pyruvate, and acetyl-CoA as junction points in metabolic pathways.
This document summarizes the biosynthesis, receptors, and pharmacological actions of eicosanoids including prostaglandins, thromboxanes, prostacyclins, and leukotrienes. It describes that these molecules are derived from arachidonic acid and produced via the cyclooxygenase and lipoxygenase pathways. The document outlines the different receptors for each eicosanoid class and their downstream signaling effects. It also provides details on the physiological and pathological roles of eicosanoids in various organ systems such as the cardiovascular, pulmonary, gastrointestinal, renal and immune systems.
This document discusses second messenger systems, which relay signals from cell surface receptors to target molecules inside cells. There are three major classes of second messenger systems: 1) the adenylyl cyclase-cAMP system, which is activated by hormones like epinephrine and glucagon and uses cAMP as the second messenger; 2) the phospholipid system, which uses IP3 and DAG as second messengers; and 3) the calcium-calmodulin system, where calcium acts as the second messenger and binds to and activates calmodulin. These second messengers amplify signals and allow hormones and neurotransmitters to trigger intracellular responses.
This document summarizes the glucuronic acid pathway, an alternative oxidative pathway for glucose metabolism. It provides UDP-glucuronic acid, which is used to conjugate bilirubin, steroids, and drugs to make them more water soluble and excretable. The pathway also synthesizes glycosaminoglycans and is involved in vitamin C synthesis in many animals. Key steps include the conversion of glucose-6-phosphate to UDP-glucuronate and the subsequent production of L-gulonate, a precursor for ascorbic acid synthesis. Certain genetic disorders can cause excess excretion of metabolites from this pathway such as L-xylulose in essential pentosuria.
This document outlines key hormones that regulate metabolic homeostasis, including insulin, glucagon, epinephrine, and cortisol. It describes their structure, biosynthesis, mechanisms of action, and metabolic effects. Insulin promotes anabolism and lowers blood glucose levels, while glucagon, epinephrine, and cortisol have catabolic effects and increase blood glucose as counterregulatory hormones opposed to insulin. Precise regulation of these hormones maintains stable blood glucose levels and fuels metabolism.
This document compares four main types of prostaglandins: PGI2, PGD2, PGE2, and PGF2α. PGI2 regulates cardiovascular homeostasis through vasodilation and platelet inhibition. PGD2 is involved in regulating sleep and pain perception in the brain and inflammation in tissues. PGE2 mediates immune responses and various physiological functions through different receptors. PGF2α derived from COX-1 plays roles in female reproduction and other processes such as renal function and inflammation.
Glycoproteins are proteins that contain carbohydrate chains covalently attached to their polypeptide side chains. They can be N-linked, O-linked, or GPI-linked. Glycoproteins serve many important functions including structure, protection, reproduction, hormones, and enzymes. Alterations in cell surface glycoproteins can impact physiology, for example certain viruses use cell surface glycoproteins to infect cells. I-cell disease results from a deficiency in an enzyme involved in glycoprotein targeting, leading to severe developmental and neurological issues.
- Glycoproteins are proteins that contain oligosaccharide chains covalently attached to their polypeptide backbones. They serve important biological roles.
- There are two main classes of glycoproteins: O-linked, where sugars attach to serine or threonine residues, and N-linked, where sugars attach to asparagine residues.
- Diseases can result from defects in glycoprotein biosynthesis, such as I-cell disease caused by a defect in N-linked glycosylation and congenital disorders of glycosylation caused by various defects impacting O-linked or N-linked glycosylation.
Prostaglandins are 20 carbon compounds derived from arachidonic acid. They are produced in various tissues and act as local hormones, regulating processes like blood pressure, reproduction, pain and fever. Examples include prostaglandin E2, D2, I2 and F2α. Prostaglandins have important biochemical actions and biomedical applications, such as treatment of ulcers, hypertension, asthma, and induction of labor.
Prostaglandins are locally-acting lipid mediators derived from arachidonic acid through the cyclooxygenase pathway. They have diverse hormone-like effects and are produced throughout the body, acting on nearby cells through G-protein coupled receptors. Prostaglandins have many functions including regulating inflammation, sensitizing neurons to pain, inducing labor, and vasodilation. They are different from true hormones as they act locally rather than at a distance and are synthesized as needed rather than being stored.
This presentation includes information about secretion of glucagon, inhibitors, regulation of secretion, mechanism of action & actions of glucagon. It also includes ways to prevention of occurrence of hyperglycemia.
1. The document discusses several hormones involved in regulating blood glucose levels, including insulin, glucagon, somatostatin, and pancreatic polypeptide.
2. Insulin decreases blood glucose levels, while glucagon and other hormones like growth hormone and cortisol increase blood glucose.
3. The liver plays an important role in maintaining blood glucose homeostasis by storing glucose as glycogen and releasing it as needed.
Second messengers are intracellular signaling molecules that are responsible for transmitting signals from hormones and neurotransmitters outside the cell to trigger physiological responses inside the cell. There are three main types of second messenger systems: cyclic nucleotides (cAMP and cGMP), phospholipid derivatives (IP3 and DAG), and calcium/calmodulin. Hormones activate G-protein coupled receptors which stimulate the production of cyclic nucleotides via adenylate cyclase or guanylate cyclase. Phospholipase C breaks down phospholipids to form IP3 and DAG. Calcium entry activates the calcium/calmodulin system. These second messengers go on to activate downstream effector proteins to elicit cellular responses.
GPCRs are the most dynamic and most abundant all the receptors. The G protein-coupled receptor (GPCR) superfamily comprises the largest and most diverse group of proteins in mammals. GPCRs are responsible for every aspect of human biology from vision, taste, sense of smell, sympathetic and parasympathetic nervous functions, metabolism, and immune regulation to reproduction. GPCRs interact with a number of ligands ranging from photons, ions, amino acids, odorants, pheromones, eicosanoids, neurotransmitters, peptides, proteins, and hormones.
Nevertheless, for the majority of GPCRs, the identity of their natural ligands is still unknown, hence remain orphan receptors.
The simple dogma that underpins much of our current understanding of GPCRs, namely,
one GPCR gene− one GPCR protein− one functional GPCR− one G protein −one response
is showing distinct signs of wear.
The document summarizes different mechanisms of hormone signal transduction. It describes how hormones bind to cell surface or intracellular receptors which then activate intracellular signaling pathways using second messengers like cAMP, IP3, DAG, calcium. These second messengers go on to affect cell functions like glycogen breakdown, lipid metabolism, transcription etc. through kinases and other effector proteins. The document also discusses G-protein coupled receptor pathway and steroid hormone signaling pathway involving hormone-receptor complexes in the cytoplasm and nucleus.
Glycogen is the storage form of carbohydrates in the human body, primarily in the liver and muscle. The liver stores glycogen to provide glucose to maintain blood sugar levels during periods of starvation. Muscle stores glycogen to act as a fuel reserve for muscle contraction, becoming depleted during prolonged exercise.
Proteoglycans are proteins that are heavily glycosylated*. The basic proteoglycan unit consists of a "core protein" with one or more covalently attached glycosaminoglycan (GAG) chain(s).
Dr. Pavani discusses G protein-coupled receptors (GPCRs), which are integral membrane proteins that sense molecules outside the cell and activate internal signal transduction pathways and cellular responses. There are over 800 GPCRs in humans that detect a wide range of ligands and are involved in many physiological processes. GPCRs work by coupling to G proteins, which activate various intracellular effectors like adenylyl cyclase, phospholipase C, and ion channels. Dysregulation of GPCR signaling can lead to many human diseases. Martin Rodbell and Alfred Gilman were awarded the 1994 Nobel Prize in Physiology or Medicine for their discoveries related to G proteins and GPCR signal transduction.
Eicosanoids mwisho.. For bettr understanding.pptxPharmTecM
The document discusses eicosanoids, which are signaling molecules derived from arachidonic acid that play roles in various physiological processes. There are three main types of eicosanoids: prostanoids, leukotrienes, and lipoxins. Prostanoids like prostaglandins and thromboxanes are derived from arachidonic acid via the cyclooxygenase pathway. Leukotrienes promote inflammation while lipoxins help resolve it. Eicosanoids act via specific receptors and are synthesized via cyclooxygenase and lipoxygenase enzymes acting on arachidonic acid. They are metabolized in the kidneys, lungs, and liver and play important roles in processes like
The principal eicosanoids of biological significance to humans are a group of molecules derived from the 20:4 (20 carbons: 4 sites of unsaturation) fatty acid, arachidonic acid.
Prostaglandins, leukotrienes, angiotensin, bradykinin, and substance P are biologically active lipid mediators that play important roles in inflammation and other physiological processes. Prostaglandins and leukotrienes are derived from arachidonic acid and function as autacoids. Angiotensin is derived from angiotensinogen and regulates blood pressure and sodium balance. Bradykinin is formed from kininogens and causes vasodilation. Substance P functions as a neurotransmitter and mediates pain, inflammation, and vasodilation. These mediators act through G-protein coupled receptors and have diverse effects in various organ systems.
Eicosanoids like prostaglandins and leukotrienes are lipid mediators derived from arachidonic acid. They have diverse pharmacological actions, including effects on the gastrointestinal, cardiovascular, renal and reproductive systems. Prostaglandins can cause contraction or relaxation of smooth muscles depending on the specific prostaglandin and tissue. Leukotrienes are important mediators of inflammation and bronchoconstriction in asthma. Platelet activating factor is a potent lipid mediator that causes platelet aggregation, increases vascular permeability, and has roles in inflammation and anaphylaxis.
Eicosanoids are signalling molecules derived from polyunsaturated fatty acids like arachidonic acid. They include prostaglandins, thromboxanes, leukotrienes, and lipoxins. Eicosanoids function as local hormones and have diverse physiological effects, such as modulating inflammation and immune responses. They are synthesized from cell membranes when needed and act locally before being rapidly degraded.
Chemistry of Prostaglandins,Leukotrienes and Thromboxanes.pptxPurushothamKN1
This document provides an overview of prostaglandins, leukotrienes, and thromboxanes. It discusses their introduction, classification, chemical structures, biosynthesis, regulation, mechanisms of action, functions, and applications. Specifically, it notes that prostaglandins are derived from arachidonic acid and have diverse hormone-like effects. Leukotrienes are inflammatory mediators produced from arachidonic acid oxidation. They are involved in inflammation and hypersensitivity reactions. Thromboxanes are involved in blood clotting and are derived from arachidonic acid through a biosynthetic pathway involving thromboxane-A-synthase.
The document discusses anti-leukotriene drugs for treating asthma and other conditions. It provides details on:
1) How leukotrienes are synthesized from arachidonic acid by the 5-lipoxygenase pathway in leukocytes and other cells. This involves enzymes like 5-lipoxygenase, FLAP, and LTA4 hydrolase.
2) The receptors that leukotrienes act on, including CysLT1, CysLT2, CysLT3, BLT1, and BLT2. CysLT1 mediates effects like bronchoconstriction while BLT1 mediates leukocyte recruitment.
3) Ways to block
Chemistry of Prostaglandins,Leukotrienes and Thromboxanes.pptxPurushothamKN1
This document provides an overview of prostaglandins, leukotrienes, and thromboxanes. It discusses their introduction, classification, chemical structures, biosynthesis, regulation, mechanisms of action, functions, and applications. Specifically, it notes that prostaglandins are derived from arachidonic acid and have diverse hormone-like effects. Leukotrienes are inflammatory mediators produced from arachidonic acid oxidation. They are involved in inflammation and hypersensitivity reactions. Thromboxanes are involved in blood clotting and are derived from arachidonic acid through the action of thromboxane-A-synthase.
Chemistry of Prostaglandins, leukotrienes and thromboxanes(Advance medicinal ...Rohit kaushiK.
This document provides an overview of a presentation on eicosanoids, prostaglandins, leukotrienes, and thromboxanes. It discusses how these compounds are synthesized from arachidonic acid and their roles in regulating cellular functions and mediating processes like inflammation, smooth muscle contraction, platelet aggregation, and uterine contraction. The presentation covers the biosynthesis, receptors, inhibitors, degradation and biochemical actions of each class of compounds.
Prostaglandins and leukotrienes are eicosanoids derived from arachidonic acid. They were first discovered in seminal fluid in the 1930s. Prostaglandins are synthesized via the cyclooxygenase pathway while leukotrienes are synthesized via the lipoxygenase pathway. These lipid mediators act on specific G-protein coupled receptors and are involved in various physiological processes like contraction and relaxation of smooth muscles, inflammation, and platelet aggregation. Due to their role in inflammation and bronchoconstriction, leukotriene receptor antagonists are used to treat asthma.
Leukotrienes are inflammatory mediators produced from the oxidation of arachidonic acid and eicosapentaenoic acid by the enzyme 5-lipoxygenase. They act on G protein-coupled receptors and are involved in asthmatic and allergic reactions. Cysteinyl leukotrienes like LTC4 and LTD4 trigger smooth muscle contractions in the bronchioles and are a major cause of inflammation in asthma. Leukotriene receptor antagonists are used to treat asthma by inhibiting leukotriene production or activity. Leukotrienes also recruit neutrophils and promote cytokine production, playing an important role in the inflammatory response.
Drugs having Pleiotropic effects, Nutraceuticals and role of antioxidants ant...SwaroopaNallabariki
This document discusses several drugs that have pleiotropic effects beyond their primary mechanism of action, including statins, SGLT2 inhibitors, metformin, thiazolidinediones, cardiac glycosides, and antithrombotic drugs. It also discusses the role of antioxidants in disease prevention and treatment. Statins have beneficial effects including improving endothelial function, reducing inflammation and oxidative stress, stabilizing plaques, and inhibiting smooth muscle proliferation. SGLT2 inhibitors and thiazolidinediones improve glycemic control and have additional vascular benefits. Metformin reshapes the gut microbiota. Antioxidants help counteract free radical damage linked to diseases. Nutraceuticals and antioxidants’ properties influence their bioavailability
Thromboxane is a lipid derived from arachidonic acid that plays an important role in blood clotting. There are two main types of thromboxane - thromboxane A2, which is produced by activated platelets and stimulates further platelet activation and aggregation, and thromboxane B2, an inactive metabolite of thromboxane A2. The primary function of thromboxane is to restrict blood flow and promote platelet aggregation, helping to form clots that stop bleeding at sites of vascular injury.
Chemistry of prostaglandins, leukotrienes and thromboxanesAbhimanyu Awasthi
The document summarizes a presentation on the chemistry of prostaglandins, leukotrienes, and thromboxanes. Prostaglandins, leukotrienes, and thromboxanes are oxygen metabolites of arachidonic acid that form a family of lipid substances with intrinsic biological activities. They are involved in processes like inflammation, platelet aggregation, and vascular homeostasis. The presentation covers their biosynthesis from arachidonic acid, sub-families, properties, and biologically important examples like prostacyclin, thromboxane A2, and leukotriene B4. It also discusses the enzymes and pathways involved in their synthesis.
Inflammatory mediators are substances that initiate and regulate inflammatory reactions. There are two types of mediators: cell-derived mediators and plasma protein-derived mediators. Mediators include histamine, serotonin, prostaglandins, leukotrienes, and platelet-activating factor. Histamine is stored in mast cells and basophils and is released during inflammatory or allergic reactions. It increases vascular permeability and contracts smooth muscle. Prostaglandins are produced in response to inflammatory stimuli and play a modulatory role in inflammation. Leukotrienes are synthesized from arachidonic acid and contribute to bronchial hyperactivity in asthma. Platelet-activating factor is secreted by various cells and produces
This document provides an overview of autacoids and the arachidonic acid cascade that produces inflammatory mediators. It defines autacoids as locally-acting substances produced by cells that have biological activity. The main classes of autacoids - amine, lipid, peptide and others - are described. The document then focuses on the arachidonic acid cascade, outlining the enzyme pathways, key players like prostaglandins and leukotrienes, and how NSAIDs inhibit parts of this cascade. The roles of these inflammatory mediators in various body systems and processes like inflammation are summarized.
Eicosanoids are derived from 20-carbon polyunsaturated fatty acids and play important roles in human physiology. They include prostaglandins, thromboxanes, and leukotrienes, which are produced via the cyclooxygenase, lipoxygenase, and epoxygenase pathways. Specific eicosanoids have roles in inflammation and pain, vascular function, bronchial contraction, gastrointestinal function, and uterine contraction. Prostaglandins and leukotrienes are involved in processes like platelet aggregation, vasodilation, smooth muscle contraction, and inflammation. They are also used therapeutically to induce labor or abortion and maintain ductus arteriosus patency in newborns.
1. Arachidonic acid is released from cell membranes and metabolized via either the cyclooxygenase pathway or lipoxygenase pathway to produce prostaglandins, thromboxanes, leukotrienes, and lipoxins.
2. These metabolites are involved in various physiological and pathological processes such as inflammation, hemostasis, smooth muscle contraction, and pain sensation.
3. Nonsteroidal anti-inflammatory drugs function by inhibiting cyclooxygenase, thereby blocking prostaglandin production and reducing inflammation.
A brief description of all topics to recent advances,SDD, host modulation and diabetes, host modulation in smokers, chemically modified tetracyclines, bisphosphonates
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...Leonel Morgado
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
Authoring a personal GPT for your research and practice: How we created the Q...Leonel Morgado
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
The binding of cosmological structures by massless topological defectsSérgio Sacani
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
The technology uses reclaimed CO₂ as the dyeing medium in a closed loop process. When pressurized, CO₂ becomes supercritical (SC-CO₂). In this state CO₂ has a very high solvent power, allowing the dye to dissolve easily.
ESR spectroscopy in liquid food and beverages.pptxPRIYANKA PATEL
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
The cost of acquiring information by natural selectionCarl Bergstrom
This is a short talk that I gave at the Banff International Research Station workshop on Modeling and Theory in Population Biology. The idea is to try to understand how the burden of natural selection relates to the amount of information that selection puts into the genome.
It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
2. Introduction to Eicosanoids
• Eicosanoids are the derivatives of the 20 carbon polyunsaturated fatty
acids (PUFA).
• Eicosanoids can act as the paracrine or autocrine hormones.
• Involved in physiological process such as platelet aggregation, pain
induction, role in reproduction and maintenance of haemodynamics of
blood.
2
3. Types of Eicosanoids
• Eicosanoids can be of following types
• Prostaglandins (PG)
• Thromboxanes (TX)
• Leukotrienes (LT)
• Infact, the discovery of the eicosanoids was based upon the
identification of prostaglandins in the human semen.
• Origin: PG = Prostate gland, TX = Platelets, LT = Leucocytes.
3
5. Nomenclature of Eicosanoids
• Prostaglandins are labelled as either E or F depending upon their
solubility in ether or fats respectively. Also, there exist PGD and PGI2
(prostacyclin).
• The numeric value (n) subscripted after the PGxn (x=E, F, D, I) defines
the number of the double bonds in side chain of the molecule such as
PGE2, PGE3, PGF2α.
• Leukotrienes are named as the LT with the third letter following A, B,
C and D based on their structure. Similar to the PG, the LT are
subscripted in by the number of double bonds in the chain.
5
7. Phospholipases
• Phospholipases are the class of enzyme
which act upon the phospholipid
molecules.
• Phospholipases can be of following
types, A1, A2, C and D. Each having a
specific cleavage site in the phospholipid
molecule.
• Phospholipase act on the extracellular as
well as intracellular membranes such as
that of the nuclear envelope and
endoplasmic reticulum.
• The activity of phospholipase is
regulated by the calcium ions and
phosphorylation of specific serine
residues. 7
C1
C2
C3
R1=Fatty acid molecule generally saturated
R2= Fatty acid molecule generally unsaturated
R3= Base group such as choline, ethanolamine etc.
Ref:
Chapter
8,
Eicosanoids,
Hormones,
2015
8. Cyclooxygenases (COX) & Lipoxygenases (LOX)
• Cyclooxygenases or COX or
Prostaglandin H synthetase is the
class of the dioxygenases that
catalyse the insertion of the oxygen
(O=O) to the substrate leading to
the formation of epoxides.
• The COX enzymes can be of two
isoforms COX 1 and COX 2.
• The binding of one monomer of the
homodimer with ligand
cooperatively activates the catalytic
activity of the other.
8
• Lipoxygenase or LOX are
monoxygeanses that catalyse the
peroxidation of the arachidonic
acid or linoleic acid.
• LOX can be 5-lipoxygenases, 12-
lipoxygenases based upon the
position of carbon they act upon.
• This enzyme is inhibited by its
product.
The activity of both the oxygenase is regulated by the calcium ion and
phosphorylation of specific serine residues.
9. Cyclooxygenase
Reaction
Peroxidase
Reaction
LT= Leukotrienes, PG= Prostaglandins, TX=
Thromboxanes, COX= Cyclooxygenase, 5-HpETE= 5-
Hydroperoxy-6,8,9,14-eicosatetranoate
Biosynthesis of Eicosanoids
9
Cytochrome P450
Ref:
Cyclooxygenase
Isozymes:
The
Biology
of
Prostaglandin
Synthesis
and
Inhibition;
Daniel
L.
Simmons
10. Transport of Eicosanoids
• To act in a paracrine manner, the
eicosanoids synthesised in the cell has
to be transported outside the
membrane.
• Influx of prostanoids: Prostaglandin
transporter (PGT)
• Efflux of prostanoids: Multidrug
resistance protein 4 (MRP4)
• For leukotrienes, multidrug resistance
protein are used for the flux across
the cell.
10
Intracellular
Extracellular
(A) PGT Structure
Intracellular
Extracellular
(B) MRP4 Structure
Ref: (A) Overview of organic anion transporters and organic anion transporter polypeptides and their roles in the liver, Ting-Ting Li,
World J Clin Cases 2019 (B) Multidrug resistance in cancer: role of ATP–dependent transporter, M. Gottesman, Medicine Nature
Reviews Cancer, 2002
11. Receptor of Eicosanoids – Prostanoids
• Prostanoids act upon the cell by acting as a ligand for the G-coupled
protein cell receptors.
• They can classified in three categories based on the result of the
downstream cell signalling.
11
Ref: Chapter 8, Eicosanoids, Hormones, 2015
12. Receptor of Eicosanoids – Leukotrienes
• Leukotrienes act upon by binding to cysteine leukotriene receptor
(CysLT 1 or CysLT 2) and leukotriene B4 receptor (BLT 1 or BLT 2).
12
BLT 1
c-AMP, Ca+2
BLT 2
c-AMP, Ca+2
LTB4 CysLT 2
Ca+2
LTC4 CysLT 1
Ca+2
LTD4
13. 13
Overview of Functions of Prostaglandins and Thromboxane
Ref:
Prostaglandins
analysis
service,
Creative
Proteomics
16. Role of Prostaglandins in Reproduction
• As known PG play a vital role in female reproductive cycle.
• PGE2 is responsible for the suppression of chemokine signalling
(caused by ovulation) causing the ECM disassembly and sperm
penetration, which leads to occurrence of the fertilization.
• PGF2α is involved in the parturition by the termination of the
progesterone production.
• Moreover, certain signals from the PGE2 receptor EP are also
responsible for the myometrial contraction at the time of parturition.
16
17. 17
Ptgs2 gene for
COX-2
Ptger2 gene for
PGE EP
receptor
Ref:
Roles
of
prostaglandin
receptors
in
female
reproduction,
Yukihiko
Sugimoto,
J.
Biochem.
2015
18. Action of Prostaglandins PGE2 and PGF2α
18
Role of PGE2 at the time of fertilization Role of PGF2α at the time of luteolysis and parturition
Ref: Roles of prostaglandin receptors in female reproduction, Yukihiko Sugimoto, J. Biochem. 2015
19. Function of Thromboxane
• Ligand based downstream
signalling leads to the synthesis of
the thromboxane in the platelets.
• Thromboxanes are responsible to
induce the platelet aggregation by
increasing the cAMP concentration
in the cell.
• Thromboxane are also acts on the
smooth muscle through myosin light
chain kinases and cause
vasoconstriction.
19
Upon binding with the ligand
such as fibrinogen, platelet
activates
Synthesis of Thromboxane A2
Binding of the TXA2 with the TP
receptor (a GPCR) on platelets
Platelet shape change
and spreading
Calcium ion concentration
increases
20. Functions of Leukotrienes
• Leukotrienes can have affect on physiology of lungs, kidney, cardio-
vasculature system and can also lead to the inflammatory diseases.
• Cysteine leukotrienes are found to constrict the pulmonary airway leading
to the asthma in patients. The use of Zafirlukast, Montelukast and 5-
lipoxygenase Zileuton has been approved against this issue.
• Cysteine leukotrienes have also been reported to cause vasoconstriction of
pulmonary arterioles. Though, it has to be studied extensively.
• The higher expression of the 5-lipoxygenase and LTA4 synthase has found
to affect the glomerular filtration rate and renal blood flow.
• The LTB4 act as a potent chemotactic agent for the infiltration of leukocytes
in GI tissue or skin.
20
21. Non Steroidal Anti-Inflammatory Drugs (NSAIDs)
• Aspirin
• Acetyl salicylate molecule that
irreversibly acetylates the serine
residues at active site.
• Acts efficiently on the COX 1
homodimer as compared to COX 2.
• Hence, it irreversibly inhibits the
activity of the COX 1.
• Ibuprofen
• Acts immediately by binding as the
antagonist to COX 1.
21
Ref:
Chapter
21,
Lehninger
Principles
of
Biochemistry,
David
L.
Nelson
22. Specific NSAIDs
• Celecoxib and Rofecoxib are
the specific drugs that inhibit
the activity of the COX 2.
• These drugs have
comparatively low interference
in the gastro-intestinal
production of the PG, as it is
required to secrete the gastric
mucin.
• Though, only celecoxib is
mostly used for the arthritis.
22
Ref: Eicosanoids in
Inflammation: Biosynthesis,
Pharmacology, and
Therapeutic Frontiers,
Subhash P. Khanapure, Current
Topics in Medicinal Chemistry,
2007
23. LOX Inhibitors & LT Receptor Antagonists
• 5-lipoxygenase Zileuton and ABT 761 are the potent inhibitors of the
5-lipoxygenase enzyme. They are effective in asthmatic treatment and
reduction in pulmonary inflammation.
• Zafirlukast; Accolate are the orally consumed indole derivates that
act the antagonist to the cysteine leukotriene receptor.
• Pro-drug (Biil284) for BLT receptor effectively inhibits the neutrophil
expression suggesting its potent role in the treatment of the
Rheumatoid arthritis.
23
24. References
• Chapter 8, Eicosanoids, Hormones, 2015 DOI: 10.1016/B978-0-12-369444-7.00008-5.
• Cyclooxygenase Isozymes: The Biology of Prostaglandin Synthesis and Inhibition; Daniel L. Simmons, Regina M. Botting, and
Timothy Hla, The American Society for Pharmacology and Experimental Therapeutics 40304/1169404, Pharmacol Rev 56:387–437,
2004.
• Eicosanoids in Inflammation: Biosynthesis, Pharmacology, and Therapeutic Frontiers, Subhash P. Khanapure, David S. Garvey,
David R. Janero and L. Gordon Letts, Current Topics in Medicinal Chemistry, 2007, 7, 311-340.
• Lehninger Principles of Biochemistry, David L. Nelson, Michael M. Cox.
• Leukotrienes: Biosynthesis, Transport, Inactivation, and Analysis, Dietrich Keppler, Rev. Physiol. Biochem. Pharmacol., Vol. 121,
1992.
• Multidrug resistance in cancer: role of ATP–dependent transporters, M. Gottesman, T. Fojo, S. Bates, Medicine Nature Reviews
Cancer, 2002.
• Overview of organic anion transporters and organic anion transporter polypeptides and their roles in the liver, Ting-Ting Li, Jia-Xing
An, Jing-Yu Xu, Bi-Guang Tuo, World J Clin Cases, Dec 6, 2019; 7(23): 3915-3933.
• Prostaglandins analysis service, Creative Proteomics.
• Roles of prostaglandin receptors in female reproduction, Yukihiko Sugimoto, Tomoaki Inazumi and Soken Tsuchiya, J. Biochem.
2015; 157(2):73–80 DOI :10.1093/jb/mvu081
• The Eicosanoids: A Historical Overview, R. Roy Baker, Clin Biochem, Vol. 23, pp. 455-458, 1990. 24
5/6 Membered ring structure with oxygen molecule bonded to the ring.
Leukotrienes are open fatty acids that might be in conjugation with the glutathione degradation product.
Number of double bonds in the parent carbon – 2 = no of double bond in the PG as one is broken a the time of the ring formation while the other broken due to the substitution of the hydroxyl group.
Arachidonic acid gives leads to the formation of the eicosanoids with 2 series while the eicosapentaenoic acid give rise to 3 series eicosanoids.
Phospholipases could be secretory or cytosolic. Secretory are found in snake venom are active upon millimolar conc. of Ca+2 whereas the cytosolic are active even at micromolar conc. For point 3, because the COX are the membrane bound enzymes present in the nuclear or endoplasmic membrane. The production of the arachidonate by PLP is rate limiting step in the Eicosanoid biosynthesis.
Isoforms of the enzyme are those which are encoded by the separate gene but function is same. The COX 2 has comparatively a larger catalytic pocket as compared to the COX 1. Contains high level of the non heme iron and trace levels of the heme iron.
COX-1 Ile 523 to Val COX-2
LOX, ATP binding Fe+2 to Fe+3; 5LO hinges at membrane through FLAP protein; Conversion starts
PGI. P450 non oxidative
PGD; glutathione-dependent H-PGDS found in mast cells and microglia; L-PGDS brain, male genital organs and cardiovascular tissues and dependent on the sulphahydral compounds .
PGE; microsomal PGES-1 and membrane bound m-PGES-2
Negatively charged molecules
Overview of organic anion transporters and organic anion transporter polypeptides and their roles in the liver
Ting-Ting Li, Jia-Xing An, Jing-Yu Xu, Bi-Guang Tuo
Multidrug resistance in cancer: role of ATP–dependent transporters
M. Gottesman, T. Fojo, S. Bates Published 2002MedicineNature Reviews Cancer
CysLT 1 is present in the lung smooth muscle cells and macrophages while CysLT 2 is present in the spleen, heart and endothelial cells.
B LT 1 is majorly present in the leukocytes while BLT 2 is omnipresent on the cellular membrane.
5-HT hydroxytryptamine or serotonin.
Nociceptors of Afferent neuron>signal to brain> Membrane depolarisation
CCL gene is responsible for the generation of the CCL7 molecules that activates the integrins which further binds to the fibronectin building ECM.PGE suppresses the activity of this gene by increasing the cAMP concentration thereby initiating the disassembly of the ECM.
This finding can be used to develop PGE antagonists that bind with EP2 receptor and block the process of fertilization.
Serine residue 530 in COX1 and 516 in COX 2
NSAIDs affects severely the female reproductive health by inhibiting the gnRH, ovulation, fertilization, luteolysis and parturition.
Aspirin dose 75mg to 110mg / day
Aspirin tolerant patients can consume antiplatelet drugs such as clopidogrel
Ibuprofen is time independent, reversible inhibition.
The COX-2 allowed the binding of these COXIB by allowing the hydrogen bonding of the sulfur pharmacophore with the arginine 499 residue. Moreover, the pocket size is large due to the replacement of phenylalanine 503 by the leucine 489.