Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.4.1.2 (acetyl-CoA carboxylase)
 2,876 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Regulation of the gene expressions of leptin, insulin receptors and lipogenic enzymes was investigated after refeeding a fat-free diet or a 10 g/100 g corn oil diet to food-deprived rats. Plasma glucose and insulin concentrations began to increase 30 min after the feeding and further increased up until 8 h. In these rats, the expression of leptin mRNA in adipose tissue began to increase significantly only 30 min after feeding, and reached a maximum at 8-16 h. However, plasma leptin levels did not increase until 4 h after refeeding, then markedly increased and reached the maximal level after 8 h. The expression of leptin mRNA and plasma leptin concentrations generally were greater in rats fed the corn oil diet compared to those fed the fat-free diet. Insulin receptor mRNA concentrations in the liver and adipose tissue began to decrease 30 min after the refeeding, in contrast to the plasma insulin increase, and continued to decrease until 8 h. The expression of acetyl-CoA carboxylase and fatty acid synthase mRNA began to increase 4-8 h after feeding and reached maximal levels at 16-24 h. Leptin treatment suppressed the expression of lipogenic enzyme mRNA in rats fed the fat-free diet but not in corn oil-fed rats, in which the expression was suppressed by polyunsaturated fatty acids and leptin expression was higher. Thus, we suggest that the glucose and insulin-dependent expressions of leptin, insulin receptors and lipogenic enzymes are coordinately and/or mutually regulated by dietary manipulation.
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PMID:Gene expressions of leptin, insulin receptors and lipogenic enzymes are coordinately regulated by insulin and dietary fat in rats. 1080 16

The molecular signaling mechanisms by which insulin leads to increased glucose transport and metabolism and gene expression are not completely elucidated. We have characterized the nature of insulin signaling defects in skeletal muscle from Type 2 diabetic patients. Insulin receptor substrate (IRS-1) phosphorylation, phosphatidylinositol (PI) 3-kinase activity, and glucose transport activity are impaired as a consequence of functional defects, whereas insulin receptor tyrosine phosphorylation, mitogen-activated protein kinase (MAPK) phosphorylation, and glycogen synthase activity are normal. Using biotinylated photoaffinity labeling, we have shown that reduced cell surface GLUT4 levels can explain glucose transport defects in skeletal muscle from Type 2 diabetic patients under insulin-stimulated conditions. Current work is focused on mechanisms behind insulin-dependent and insulin-independent regulation of glucose uptake. We have recently determined the independent effects of insulin and hypoxia/AICAR exposure on glucose transport and cell surface GLUT4 content in skeletal muscle from nondiabetic and Type 2 diabetic subjects. Hypoxia and AICAR increase glucose transport via an insulin-independent mechanism involving activation of 5'-AMP-activated kinase (AMPK). AMPK signaling is intact, because 5-aminoimidazole-4-carboxamide 1-beta-D-ribonucleoside (AICAR) increased AMPK and acetyl-CoA carboxylase (ACC) phosphorylation to a similar extent in Type 2 diabetic and nondiabetic subjects. However, AICAR responses on glucose uptake were impaired. Our studies highlight important AMPK-dependent and independent pathways in the regulation of GLUT4 and glucose transport activity in insulin resistant skeletal muscle. Understanding signaling mechanisms to downstream metabolic responses may provide valuable clues to a future therapy for Type 2 diabetes.
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PMID:Sending the signal: molecular mechanisms regulating glucose uptake. 1523 28