Insulin is a key hormone regulating glucose homeostasis and has many cellular effects on metabolism, growth, and differentiation. Insulin action is mediated through a specific cell-surface receptor. The first step following insulin binding consists in receptor autophosphorylation and stimulation of its tyrosine kinase activity. Among the multiple substrates, the insulin receptor substrate-1 (IRS-1) is the major cytoplasmic substrate for insulin. IRS-1 binds several Src homology 2 (SH2) proteins through its multiple tyrosine phosphorylation sites: phosphatidylinositol 3-kinase (PI 3-kinase), the Ras guanine-nucleotide-releasing complex Grb2-SOS, the tyrosine phosphatase Syp, and the adapter protein Nck. IRS-1 is essential for many, but not all of the insulin's biological responses. Recently, a primary alternative substrate, i.e. IRS-2, was purified and cloned. Numerous biochemical abnormalities of the insulin signaling system lead to insulin resistance. No doubt, the recent data about the molecular mechanisms of insulin action will provide new insights into the pathophysiology and therapy of diabetes and other insulin resistant states.
{"title":"[The insulin transduction system].","authors":"V Mitev","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Insulin is a key hormone regulating glucose homeostasis and has many cellular effects on metabolism, growth, and differentiation. Insulin action is mediated through a specific cell-surface receptor. The first step following insulin binding consists in receptor autophosphorylation and stimulation of its tyrosine kinase activity. Among the multiple substrates, the insulin receptor substrate-1 (IRS-1) is the major cytoplasmic substrate for insulin. IRS-1 binds several Src homology 2 (SH2) proteins through its multiple tyrosine phosphorylation sites: phosphatidylinositol 3-kinase (PI 3-kinase), the Ras guanine-nucleotide-releasing complex Grb2-SOS, the tyrosine phosphatase Syp, and the adapter protein Nck. IRS-1 is essential for many, but not all of the insulin's biological responses. Recently, a primary alternative substrate, i.e. IRS-2, was purified and cloned. Numerous biochemical abnormalities of the insulin signaling system lead to insulin resistance. No doubt, the recent data about the molecular mechanisms of insulin action will provide new insights into the pathophysiology and therapy of diabetes and other insulin resistant states.</p>","PeriodicalId":79449,"journal":{"name":"Molekuliarna meditsina = Molecular medicine","volume":"1 2","pages":"4-8"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19946037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work reviews clonal rearrangements of T-cell receptor genes in peripheral T-cells of patients with lymphoproliferative diseases. The role of T-cell genes for predisposition to autoimmune diseases is analysed. Methodological approaches for analysis of T-cell receptor repertoire and autoimmune diseases are presented. The role of T-cell receptor-antigen recognitions in IgE mediated allergic reactions is described.
{"title":"[The T-cell receptor--its participation in the pathological immune response].","authors":"B Bozhkov","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>This work reviews clonal rearrangements of T-cell receptor genes in peripheral T-cells of patients with lymphoproliferative diseases. The role of T-cell genes for predisposition to autoimmune diseases is analysed. Methodological approaches for analysis of T-cell receptor repertoire and autoimmune diseases are presented. The role of T-cell receptor-antigen recognitions in IgE mediated allergic reactions is described.</p>","PeriodicalId":79449,"journal":{"name":"Molekuliarna meditsina = Molecular medicine","volume":"1 2","pages":"9-15"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19946038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Candidate genes for the familial forms of breast and ovarian carcinomas (BRCA)].","authors":"A Markov","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":79449,"journal":{"name":"Molekuliarna meditsina = Molecular medicine","volume":"1 1","pages":"17-20"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19938127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The important role of the natural polyamines putrescine, spermidine and spermine in the normal and pathological cell growth is the main reason for the active investigation of their metabolism. The essential catabolic reactions of polyamine interconversion and terminal oxidation as well as data for the catabolic enzymes and the regulatory mechanisms of their activities are reviewed. The importance of catabolic reactions for the maintenance of the optimal polyamine concentrations during the cell growth and differentiation is also presented. The role of the essential catabolic enzymes spermidine/spermine N1-acetyltransferase, polyamine oxidase and diamine oxidase in normal and pathological cell growth is discussed.
{"title":"[The catabolism of polyamines].","authors":"V Pavlov, O Dimitrov","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The important role of the natural polyamines putrescine, spermidine and spermine in the normal and pathological cell growth is the main reason for the active investigation of their metabolism. The essential catabolic reactions of polyamine interconversion and terminal oxidation as well as data for the catabolic enzymes and the regulatory mechanisms of their activities are reviewed. The importance of catabolic reactions for the maintenance of the optimal polyamine concentrations during the cell growth and differentiation is also presented. The role of the essential catabolic enzymes spermidine/spermine N1-acetyltransferase, polyamine oxidase and diamine oxidase in normal and pathological cell growth is discussed.</p>","PeriodicalId":79449,"journal":{"name":"Molekuliarna meditsina = Molecular medicine","volume":"1 2","pages":"16-21"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19945405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nitric oxide (NO) exerts its vasodilatator effect in smooth muscle by activation of guanylyl cyclase. This in turn leads to decreases in intracellular calcium and dephosphorylation of myosin light chains and relaxation. NO is synthesised from L-arginine by a family of enzymes called Nitric oxide synthase (NOS). In the vascular system two isoenzymes of NOS are largely expressed: the constitutive NOS and the inducible NOS. The constitutive NOS identified in the endothelium generates NO continuously providing the vasodilatator tone and modulating platelet function. NOS type 1 is expressed in preoptic and infundibular nucleus of hypothalamus. NO acts as presynaptic agonist of glutamatergic NMDA-receptor mediation in the motor nucleus of nervus vagus. NO decreases the frequency of the spontaneous discharges in the carotid bodies. NO is involved in the processes of synaptic plasticity in the hippocampus.
{"title":"[The participation of nitric oxide in the functions of the central nervous system and the cardiovascular system].","authors":"I Krushkov, Ts Markova, A Tsankov","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Nitric oxide (NO) exerts its vasodilatator effect in smooth muscle by activation of guanylyl cyclase. This in turn leads to decreases in intracellular calcium and dephosphorylation of myosin light chains and relaxation. NO is synthesised from L-arginine by a family of enzymes called Nitric oxide synthase (NOS). In the vascular system two isoenzymes of NOS are largely expressed: the constitutive NOS and the inducible NOS. The constitutive NOS identified in the endothelium generates NO continuously providing the vasodilatator tone and modulating platelet function. NOS type 1 is expressed in preoptic and infundibular nucleus of hypothalamus. NO acts as presynaptic agonist of glutamatergic NMDA-receptor mediation in the motor nucleus of nervus vagus. NO decreases the frequency of the spontaneous discharges in the carotid bodies. NO is involved in the processes of synaptic plasticity in the hippocampus.</p>","PeriodicalId":79449,"journal":{"name":"Molekuliarna meditsina = Molecular medicine","volume":"1 2","pages":"21-7"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19945408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号