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PPAR-gamma
Peroxisome proliferator-activated receptor gamma (PPAR-γ or PPARG), also known as the glitazone reverse insulin resistance receptor, or NR1C3 (nuclear receptor subfamily 1, group C, member 3) is a type II nuclear receptor functioning as a transcription factor that in humans is encoded by the ''PPARG'' gene. Tissue distribution PPARG is mainly present in adipose tissue, colon and macrophages. Two isoforms of PPARG are detected in the human and in the mouse: PPAR-γ1 (found in nearly all tissues except muscle) and PPAR-γ2 (mostly found in adipose tissue and the intestine). Gene expression This gene encodes a member of the peroxisome proliferator-activated receptor (PPAR) subfamily of nuclear receptors. PPARs form heterodimers with retinoid X receptors (RXRs) and these heterodimers regulate transcription of various genes. Three subtypes of PPARs are known: PPAR-alpha, PPAR-delta, and PPAR-gamma. The protein encoded by this gene is PPAR-gamma and is a regulator of adipocyte dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adipogenesis
Adipogenesis is the formation of adipocytes (fat cells) from stem cells. It involves 2 phases, determination, and terminal differentiation. Determination is mesenchymal stem cells committing to the adipocyte precursor cells, also known as lipoblasts or preadipocytes which lose the potential to differentiate to other types of cells such as chondrocytes, myocytes, and osteoblasts. Terminal differentiation is that preadipocytes differentiate into mature adipocytes. Adipocytes can arise either from preadipocytes resident in adipose tissue, or from bone-marrow derived progenitor cells that migrate to adipose tissue. Introduction Adipocytes play a vital role in energy homeostasis and process the largest energy reserve as triglycerol in the body of animals. Adipocytes stay in a dynamic state, they start expanding when the energy intake is higher than the expenditure and undergo mobilization when the energy expenditure exceeds the intake. This process is highly regulated by counter reg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxisome Proliferator-activated Receptor
In the field of molecular biology, the peroxisome proliferator–activated receptors (PPARs) are a group of nuclear receptor proteins that function as transcription factors regulating gene expression. PPARs play essential roles in regulating cell differentiation, cellular differentiation, developmental biology, development, and metabolism (carbohydrate metabolism, carbohydrate, lipid metabolism, lipid, protein metabolism, protein), and tumorigenesis Nomenclature and tissue distribution Three types of PPARs have been identified: alpha, PPARG, gamma, and delta (beta): * Peroxisome proliferator-activated receptor alpha, α (alpha) - expressed in liver, kidney, heart, muscle, adipose tissue, and others * Peroxisome proliferator-activated receptor delta, β/δ (beta/delta) - expressed in many tissues, especially in brain, adipose tissue, and skin * Peroxisome proliferator-activated receptor gamma, γ (gamma) - although transcribed by the same gene, this PPAR, by way of alternativ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Receptor
In the field of molecular biology, nuclear receptors are a class of proteins responsible for sensing steroids, thyroid hormones, vitamins, and certain other molecules. These intracellular receptors work with other proteins to regulate the expression of specific genes, thereby controlling the development, homeostasis, and metabolism of the organism. Nuclear receptors bind directly to DNA regulating the expression of adjacent genes; hence these receptors are classified as transcription factors. The regulation of gene expression by nuclear receptors often occurs in the presence of a ligand—a molecule that affects the receptor's behavior. Ligand binding to a nuclear receptor results in a conformational change activating the receptor. The result is up- or down-regulation of gene expression. A unique property of nuclear receptors that differentiates them from other classes of receptors is their direct control of genomic DNA. Nuclear receptors play key roles in both embryonic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FGF21
Fibroblast growth factor 21 (FGF-21) is a protein that in mammals is encoded by the ''FGF21'' gene. The protein encoded by this gene is a member of the fibroblast growth factor (FGF) family and specifically a member of the endocrine subfamily which includes FGF23 and FGF15/19. FGF21 is the primary endogenous agonist of the FGF21 receptor, which is composed of the co-receptors FGF receptor 1 and β-Klotho. FGF family members possess broad mitogenic and cell survival activities and are involved in a variety of biological processes including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. FGFs act through a family of four FGF receptors. Binding is complicated and requires both interaction of the FGF molecule with an FGF receptor and binding to heparin through a heparin binding domain. Endocrine FGFs lack a heparin binding domain and thus can be released into the circulation. FGF21 is a hepatokine – i.e., a hormone secreted by the liv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxisome Proliferator-activated Receptor Alpha
Peroxisome proliferator-activated receptor alpha (PPAR-α), also known as NR1C1 (nuclear receptor subfamily 1, group C, member 1), is a nuclear receptor protein functioning as a transcription factor that in humans is encoded by the ''PPARA'' gene. Together with peroxisome proliferator-activated receptor delta and peroxisome proliferator-activated receptor gamma, PPAR-alpha is part of the subfamily of peroxisome proliferator-activated receptors. It was the first member of the PPAR family to be cloned in 1990 by Stephen Green and has been identified as the nuclear receptor for a diverse class of rodent Liver, hepatocarcinogens that causes proliferation of peroxisomes. Expression PPAR-α is primarily activated through ligand binding. Endogenous ligands include fatty acids such as arachidonic acid as well as other polyunsaturated fatty acids and various fatty acid-derived compounds such as certain members of the 15-hydroxyicosatetraenoic acid, 15-hydroxyeicosatetraenoic acid family ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyunsaturated Fatty Acids
In biochemistry and nutrition, a polyunsaturated fat is a fat that contains a polyunsaturated fatty acid (abbreviated PUFA), which is a subclass of fatty acid characterized by a backbone with two or more carbon–carbon double bonds. Some polyunsaturated fatty acids are essentials. Polyunsaturated fatty acids are precursors to and are derived from polyunsaturated fats, which include drying oils. Nomenclature The position of the carbon-carbon double bonds in carboxylic acid chains in fats is designated by Greek letters. The carbon atom closest to the carboxyl group is the ''alpha'' carbon, the next carbon is the ''beta'' carbon and so on. In fatty acids the carbon atom of the methyl group at the end of the hydrocarbon chain is called the ''omega'' carbon because ''omega'' is the last letter of the Greek alphabet. Omega-3 fatty acids have a double bond three carbons away from the methyl carbon, whereas omega-6 fatty acids have a double bond six carbons away from the methyl ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ABCA1
ATP-binding cassette transporter ABCA1 (member 1 of human transporter sub-family ABCA), also known as the ''cholesterol efflux regulatory protein'' (CERP) is a protein which in humans is encoded by the ''ABCA1'' gene. This transporter is a major regulator of cellular cholesterol and phospholipid homeostasis. Tangier disease It was discovered that a mutation in the ABCA1 protein is responsible for causing Tangier disease by several groups in 1998. Gerd Schmitz's group in Germany and Michael Hayden's group in British Columbia were using standard genetics techniques and DNA from family pedigrees to locate the mutation. Richard Lawn's group at CV Therapeutics in Palo Alto, CA used cDNA microarrays, which were relatively new at the time, to assess gene expression profiles from cell lines created from normal and affected individuals. They showed cell lines from patients with Tangier's disease showed differential regulation of the ABCA1 gene. Subsequent sequencing of the gene identifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Cholesterol Transport
Reverse cholesterol transport (RCT) is a multistep process comprising removal of excess cholesterol from cells in the body and delivery to the liver for excretion into the small intestine. Enhancing reverse cholesterol transport is considered a potential strategy for preventing and treating atherosclerosis and associated diseases such as cardiovascular disease and stroke. Atherosclerosis is caused by the build-up in arterial blood vessels of atherosclerotic plaques. These consist mostly of foam cells, which are macrophages overloaded with cholesterol and other lipids. Foam cells and other cells in peripheral tissues can hand over their excess cholesterol to high-density lipoprotein (HDL) particles. These will transport the cholesterol via the lymph and then the blood stream to the liver, from where it will be excreted with bile into the small intestine. Reverse cholesterol transport thereby works against the build-up of atherosclerotic plaques from dying foam cells. In more deta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liver X Receptor
The liver X receptor (LXR) is a member of the nuclear receptor family of transcription factors and is closely related to nuclear receptors such as the PPARs, FXR and RXR. Liver X receptors (LXRs) are important regulators of cholesterol, fatty acid, and glucose homeostasis. LXRs were earlier classified as orphan nuclear receptors, however, upon discovery of endogenous oxysterols as ligands they were subsequently deorphanized. Two isoforms of LXR have been identified and are referred to as LXRα and LXRβ. The liver X receptors are classified into subfamily 1 ( thyroid hormone receptor-like) of the nuclear receptor superfamily, and are given the nuclear receptor nomenclature symbols NR1H3 (LXRα) and NR1H2 (LXRβ) respectively. LXRα and LXRβ were discovered separately between 1994-1995. LXRα isoform was independently identified by two groups and initially named RLD-1 and LXR, whereas four groups identified the LXRβ isoform and called it UR, NER, OR-1, and RIP-15. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5-hydroxyicosatetraenoic Acid
5-Hydroxyeicosatetraenoic acid (5-HETE, 5(''S'')-HETE, or 5''S''-HETE) is an eicosanoid, i.e. a metabolite of arachidonic acid. It is produced by diverse cell types in humans and other animal species. These cells may then metabolize the formed 5(''S'')-HETE to 5-oxo-eicosatetraenoic acid (5-oxo-ETE), 5(''S''),15(''S'')-dihydroxyeicosatetraenoic acid (5(''S''),15(''S'')-diHETE), or 5-oxo-15-hydroxyeicosatetraenoic acid (5-oxo-15(''S'')-HETE). 5(''S'')-HETE, 5-oxo-ETE, 5(''S''),15(''S'')-diHETE, and 5-oxo-15(''S'')-HETE, while differing in potencies, share a common mechanism for activating cells and a common set of activities. They are therefore a family of structurally related metabolites. Animal studies and a limited set of human studies suggest that this family of metabolites serve as hormone-like autocrine and paracrine signalling agents that contribute to the up-regulation of acute inflammatory and allergic responses. In this capacity, these metabolites may be members of the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachidonic Acid
Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega−6 fatty acid 20:4(ω−6), or 20:4(5,8,11,14). It is a precursor in the formation of leukotrienes, prostaglandins, and thromboxanes. Together with omega−3 fatty acids and other omega−6 fatty acids, arachidonic acid provides energy for body functions, contributes to cell membrane structure, and participates in the synthesis of eicosanoids, which have numerous roles in physiology as signaling molecules. Its name derives from the ancient Greek neologism ''arachis'' 'peanut', although peanut oil does not contain any arachidonic acid. Arachidonate is the name of the derived carboxylate anion ( conjugate base of the acid), salts, and some esters. Chemistry In chemical structure, arachidonic acid is a carboxylic acid with a 20-carbon chain and four '' cis''- double bonds; the first double bond is located at the sixth carbon from the omega end. Some chemistry sources define 'arachidonic acid' to designa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophage Polarization
Macrophage polarization is a process by which macrophages adopt different functional programs in response to the signals from their microenvironment. This ability is connected to their multiple roles in the organism: they are powerful effector cells of the innate immune system, but also important in removal of cellular debris, embryonic development and tissue repair. By simplified classification, macrophage phenotype has been divided into 2 groups: M1 (classically activated macrophages) and M2 (alternatively activated macrophages). This broad classification was based on ''in vitro'' studies, in which cultured macrophages were treated with molecules that stimulated their phenotype switching to a particular state. In addition to chemical stimulation, it has been shown that the stiffness of the underlying substrate a macrophage is grown on can direct polarization state, functional roles and migration mode. A continuum of M1-M2 polarization may arise even in the absence of polarizing cy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
