Short-term in vitro Inhibition of Glycogen - 1582 Words

Introduction: Overt type 2 diabetes mellitus is the most prevalent form of diabetes, accounting for approximately 90% of the 20.8 million cases in the United States. Unlike type 1 diabetes mellitus, type 2 diabetes mellitus is most commonly caused by a defect in insulin action on cells rather than by a defect in the insulin itself1. It has recently been shown that overactivity of glycogen synthase kinase 3 (GSK-3) may be implicated in the impaired insulin action2. Although GSK-3 is a distal element of the insulin signaling pathway (which includes insulin receptor substrate 1 or IRS-1), when it is overactive, this affects both insulin signaling and the removal of glucose from the blood stream by skeletal muscle. Firstly, when†¦show more content†¦In addition, the tyrosine-phosporylated IR and IRS-1 measured using the same method used to assess insulin signaling. Results: 3.1 GSK-3 serine phosphorylation in soleus muscle from lean Zucker and ZDF rats. 3.2 Effects of GSk-3 inhibition in glucose transport activity 3.3 Effects of GSK-3 inhibition on insulin signaling functionality 3.1 GSK-3 serine phosphorylation in soleus muscle from lean Zucker and ZDF rats. In order to evaluate the activity state of GSK-3 in the skeletal muscle of ZDF rats, the phosphorylation of the GSK-3ÃŽ ² Ser9 was measured. This information was then compared to the data obtained from lean Zucker rats. The first test was conducted in the absence of insulin and showed that the GSK-3ÃŽ ² Ser9 phosphorylation of the ZDF rats was significantly less [36%] than that of the lean Zucker rats. The second test performed between the lean Zucker and ZDF rats was identical to the first minus one aspect: the presence of insulin. When given insulin, the phosphorylation of the GSK-3ÃŽ ² Ser9 in ZDF rats was considerably less [35%] than the phosphorylation in lean Zucker rats. These findings were expected because type 2 diabetes lowers an organism’s ability to phosphorylate GSK-3ÃŽ ² Ser9. This lowered ability is inversely related to GSK-3 activity. Thus, the ZDF rats, which have type 2 diabetes, had a higher activity rate of GSK-3 in their skeletal muscles than the lean Zuck er rats. Finally,Show MoreRelatedCognitive Impairment Of Alzheimer s Disease1313 Words   |  6 Pages(Garcia-Osta Alberini, 2009). The microtubule stabilizing protein tau may become hyper-phosphorylated in AD due to the presence of high levels of AÃŽ ². Hoshi et al (1996) showed that AÃŽ ² exposure to rat hippocampal neurons in vitro produced increased levels of the tau kinase GSK-3 (glycogen synthase kinase 3) which in turn hyper-phosphorylated tau leading to cellular death. (Hoshi et al., 1996) The neurotoxicity of tau may not be produced solely because of GSK-3, but may be due to improper microtubule stabilizationRead MoreMyocardial Infaraction6192 Words   |  25 Pagesoverall and by type. Existing studies have been largely limited by modest sample sizes, limited diversity within the study populations, the use of composite end points that combine disparate outcomes, and the inability to characterize the effect of long-term outpatient medication use on observed trends in inci dence and severity of myocardial infarction. CONCLUSION: More contemporary assessments of community-wide changes in the epidemiology of myocardial infarction are needed to help assess the effectivenessRead MoreCell Biology Final Essay30093 Words   |  121 Pagesimmortal cell lines. 54. The growth factor that stimulates fibroblasts to divide around a wound is released by A) other fibroblasts. B) capillary endothelial cells. C) platelets. D) lymphocytes. 55. Robert Hooke first coined the term â€Å"cell† following his observation of the pattern of cell walls in cork with a light microscope. A) True B) False 56. Because the wavelength of electrons is 100,000 times shorter than the wavelength of visible light, the resolution of the electron