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Matrine Oxide
Oxymatrine (matrine oxide, matrine ''N''-oxide, matrine 1-oxide) is one of many quinolizidine alkaloid compounds extracted from the root of ''Sophora flavescens'', a Chinese herb. It is very similar in structure to matrine, which has one less oxygen atom. Oxymatrine has a variety of effects ''in vitro'' and in animal models, including protection against apoptosis, tumor and fibrotic tissue development, and inflammation. Furthermore, oxymatrine has been shown to decrease cardiac ischemia (decreased blood perfusion), myocardial injury, arrhythmias (irregular heartbeats), and improve heart failure by increasing cardiac function. Role in cardiac fibrosis Recent research has shown that oxymatrine prevents cardiac fibrosis in rats.Shen, X, Yang, Y, Xiao, T, Peng, J, Liu, X. (2011) Protective effect of oxymatrine on myocardial fibrosis induced by acute myocardial infarction in rats involved in TGF-b1-Smads signal pathway. Journal of Asian Natural Products Research 13: 215-224 The developm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinolizidine Alkaloids
Quinolizidine alkaloids are natural products that have a quinolizidine structure; this includes the lupine alkaloids. Occurrence Quinolizidine alkaloids can be found in the plant family of legumes, especially in papilionaceous plants. While the lupine alkaloids (following their name) can be found in lupines, tinctorin, for example, was isolated from the dyer's broom. Examples More than 200 quinolizidine alkaloids are known which can be classified into 6 structural types: * the lupinine type with 34 known structures, including lupinine and its derivatives * the camoensine type with 6 known structures, including camoensin * the spartein type with 66 structures, including sparteine, lupanine, angustifoline * the α-pyridone type with 25 structures, including anagyrine and cytisine * the matrine type with 31 structures, including matrine * and the ormosanin type with 19 structures, including ormosanine. (–)-Lupinine Structural Formula V2.svg, Lupinine, (–)-lupinine (6R,7 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extracellular Matrix
In biology, the extracellular matrix (ECM), also called intercellular matrix (ICM), is a network consisting of extracellular macromolecules and minerals, such as collagen, enzymes, glycoproteins and hydroxyapatite that provide structural and biochemical support to surrounding cells. Because multicellularity evolved independently in different multicellular lineages, the composition of ECM varies between multicellular structures; however, cell adhesion, cell-to-cell communication and differentiation are common functions of the ECM. The animal extracellular matrix includes the interstitial matrix and the basement membrane. Interstitial matrix is present between various animal cells (i.e., in the intercellular spaces). Gels of polysaccharides and fibrous proteins fill the interstitial space and act as a compression buffer against the stress placed on the ECM. Basement membranes are sheet-like depositions of ECM on which various epithelial cells rest. Each type of connective tissue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P-glycoprotein
P-glycoprotein 1 (permeability glycoprotein, abbreviated as P-gp or Pgp) also known as multidrug resistance protein 1 (MDR1) or ATP-binding cassette sub-family B member 1 (ABCB1) or cluster of differentiation 243 (CD243) is an important protein of the cell membrane that pumps many foreign substances out of cells. More formally, it is an ATP-dependent efflux pump with broad substrate specificity. It exists in animals, fungi, and bacteria, and it likely evolved as a defense mechanism against harmful substances. P-gp is extensively distributed and expressed in the intestinal epithelium where it pumps xenobiotics (such as toxins or drugs) back into the intestinal lumen, in liver cells where it pumps them into bile ducts, in the cells of the proximal tubule of the kidney where it pumps them into urinary filtrate (in the proximal tubule), and in the capillary endothelial cells composing the blood–brain barrier and blood–testis barrier, where it pumps them back into the ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dose–response Relationship
The dose–response relationship, or exposure–response relationship, describes the magnitude of the Stimulus–response model, response of an organism, as a Function (mathematics), function of exposure (or Dose (biochemistry), doses) to a Stimulus (physiology), stimulus or stressor (usually a chemical) after a certain exposure time. Dose–response relationships can be described by dose–response curves. This is explained further in the following sections. A stimulus response function or stimulus response curve is defined more broadly as the response from any type of stimulus, not limited to chemicals. Motivation for studying dose–response relationships Studying dose response, and developing dose–response models, is central to determining "safe", "hazardous" and (where relevant) beneficial levels and dosages for drugs, pollutants, foods, and other substances to which humans or other organisms are exposed. These conclusions are often the basis for public policy. The Unit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signal Transduction
Signal transduction is the process by which a chemical or physical signal is transmitted through a cell as a biochemical cascade, series of molecular events. Proteins responsible for detecting stimuli are generally termed receptor (biology), receptors, although in some cases the term sensor is used. The changes elicited by ligand (biochemistry), ligand binding (or signal sensing) in a receptor give rise to a biochemical cascade, which is a chain of biochemical events known as a Cell signaling#Signaling pathways, signaling pathway. When signaling pathways interact with one another they form networks, which allow cellular responses to be coordinated, often by combinatorial signaling events. At the molecular level, such responses include changes in the transcription (biology), transcription or translation (biology), translation of genes, and post-translational modification, post-translational and conformational changes in proteins, as well as changes in their location. These molecula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smad4
SMAD4, also called SMAD family member 4, Mothers against decapentaplegic homolog 4, or DPC4 (Deleted in Pancreatic Cancer-4) is a highly conserved protein present in all metazoans. It belongs to the SMAD family of transcription factor proteins, which act as mediators of TGF-β signal transduction. The TGFβ family of cytokines regulates critical processes during the lifecycle of metazoans, with important roles during embryo development, tissue homeostasis, regeneration, and immune regulation. SMAD 4 belongs to the co-SMAD group (''common mediator'' SMAD), the second class of the SMAD family. SMAD4 is the only known co-SMAD in most metazoans. It also belongs to the Dwarfin family of proteins that modulate members of the TGFβ protein superfamily, a family of proteins that all play a role in the regulation of cellular responses. Mammalian SMAD4 is a homolog of the ''Drosophila'' protein " Mothers against decapentaplegic" named Medea. SMAD4 interacts with R-Smads, such as SMA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smad3
Mothers against decapentaplegic homolog 3 also known as SMAD family member 3 or SMAD3 is a protein that in humans is encoded by the SMAD3 gene. SMAD3 is a member of the SMAD (protein), SMAD family of proteins. It acts as a mediator of the signals initiated by the transforming growth factor beta (TGF-β) superfamily of cytokines, which regulate cell proliferation, differentiation and death. Based on its essential role in TGF beta signaling pathway, SMAD3 has been related with tumor growth in cancer development. Gene The human SMAD3 gene is located on chromosome 15 (human), chromosome 15 on the cytogenic band at 15q22.33. The gene is composed of 9 exons over 129,339 base pairs. It is one of several human homology (biology), homologues of a gene that was originally discovered in the fruit fly ''Drosophila, Drosophila melanogaster''. The expression of SMAD3 has been related to the mitogen-activated protein kinase (MAPK/ERK pathway), particularly to the activity of mitogen-activat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smad2
Mothers against decapentaplegic homolog 2, also known as SMAD family member 2 or SMAD2, is a protein that in humans is encoded by the ''SMAD2'' gene. MAD homolog 2 belongs to the SMAD, a family of proteins similar to the gene products of the ''Drosophila'' gene ' mothers against decapentaplegic' (Mad) and the '' C. elegans'' gene Sma. SMAD proteins are signal transducers and transcriptional modulators that mediate multiple signaling pathways. Function SMAD2 mediates the signal of the transforming growth factor (TGF)-beta, and thus regulates multiple cellular processes, such as cell proliferation, apoptosis, and differentiation. This protein is recruited to the TGF-beta receptors through its interaction with the SMAD anchor for receptor activation (SARA) protein. In response to TGF-beta signal, this protein is phosphorylated by the TGF-beta receptors. The phosphorylation induces the dissociation of this protein with SARA and the association with the family member SMA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine/threonine-specific Protein Kinase
A serine/threonine protein kinase () is a kinase enzyme, in particular a protein kinase, that phosphorylation, phosphorylates the hydroxyl, OH group of the amino acid, amino-acid residues serine or threonine, which have similar side chains. At least 350 of the 500+ human protein kinases are serine/threonine kinases (STK). In enzymology, the term ''serine/threonine protein kinase'' describes a class of enzymes in the family of transferases, that transfer phosphates to the oxygen atom of a serine or threonine side chain in proteins. This process is called phosphorylation. Protein phosphorylation in particular plays a significant role in a wide range of cellular processes and is a very important post-translational modification. The chemical reaction performed by these enzymes can be written as :ATP + a protein \rightleftharpoons ADP + a phosphoprotein Thus, the two substrate (biochemistry), substrates of this enzyme are adenosine triphosphate, ATP and a protein, whereas its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TGF Beta Receptor 2
Transforming growth factor, beta receptor II (70/80kDa) is a TGF beta receptor. ''TGFBR2'' is its human gene. It is a tumor suppressor gene. Function This gene encodes a member of the serine/threonine protein kinase family and the TGFB receptor subfamily. The encoded protein is a transmembrane protein that has a protein kinase domain, forms a heterodimeric complex with another receptor protein, and binds TGF-beta. This receptor/ligand complex phosphorylates proteins, which then enter the nucleus and regulate the transcription of a subset of genes related to cell proliferation. Mutations in this gene have been associated with Marfan syndrome, Loeys-Deitz aortic aneurysm syndrome, Osler–Weber–Rendu syndrome, and the development of various types of tumors. At least 73 disease-causing mutations in this gene have been discovered. Alternatively spliced transcript variants encoding different isoforms have been characterized. Interactions TGF beta receptor 2 has been shown t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TGF Beta Receptor 1
Transforming growth factor beta receptor I (activin A receptor type II-like kinase, 53kDa) is a membrane-bound TGF beta receptor protein of the TGF-beta receptor family for the TGF beta superfamily of signaling ligands. ''TGFBR1'' is its human gene. Function The protein encoded by this gene forms a heteromeric complex with type II TGF-β receptors when bound to TGF-β, transducing the TGF-β signal from the cell surface to the cytoplasm. The encoded protein is a serine/threonine protein kinase. Mutations in this gene have been associated with Loeys–Dietz aortic aneurysm syndrome (LDS, LDAS). Interactions TGF beta receptor 1 has been shown to interact with: * Caveolin 1, * Endoglin, * FKBP1A, * FNTA, * Heat shock protein 90kDa alpha (cytosolic), member A1 * Mothers against decapentaplegic homolog 7, * PPP2R2A, * STRAP, * TGF beta 1, and * TGF beta receptor 2. Inhibitors * GW-788388 * LY-2109761 * Galunisertib (LY-2157299) * SB-431542 * SB-52 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TGF Beta 1
Transforming growth factor beta 1 or TGF-β1 is a polypeptide member of the transforming growth factor beta superfamily of cytokines. It is a secreted protein that performs many cellular functions, including the control of cell growth, cell proliferation, cell differentiation, and apoptosis. In humans, TGF-β1 is encoded by the gene. Function TGF-β is a multifunctional set of peptides that controls proliferation, differentiation, and other functions in many cell types. TGF-β acts synergistically with transforming growth factor-alpha (TGF-α) in inducing transformation. It also acts as a negative autocrine growth factor. Dysregulation of TGF-β activation and signaling may result in apoptosis. Many cells synthesize TGF-β and almost all of them have specific receptors for this peptide. TGF-β1, TGF-β2, and TGF-β3 all function through the same receptor signaling systems. TGF-β1 was first identified in human platelets as a protein with a molecular mass of 25 kil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
