L Guo1, B He2, P Fang2, P Bo2, Z Zhang3. 1. Department of Physical Education, Chuzhou College, Chuzhou, 239012, Anhui, China. 2. Department of Endocrinology, Clinical Medical College, Yangzhou University, Nantong Street #98, Yangzhou, 225001, China. 3. Department of Endocrinology, Clinical Medical College, Yangzhou University, Nantong Street #98, Yangzhou, 225001, China. shimyyz@126.com.
Abstract
PURPOSE: Our and other's studies showed that administration of neuropeptide galanin may mitigate insulin resistance via promoting glucose transporter 4 (GLUT4) expression and translocation in rats. The objective of this study is to investigate whether galanin receptor 2 (GAL2-R) in brain mediates the ameliorative effect of galanin on insulin resistance in adipose tissues of type 2 diabetic rats. METHODS: In this study galanin, GAL2-R agonist M1145 and GAL2-R antagonist M871 were respectively or cooperatively injected into intracerebroventricles of type 2 diabetic rats once a day for successive fifteen days. Then the plasma and fat tissues of rats were used to estimate the alterations of insulin resistance indexes. RESULTS: The central administration of galanin enhanced 2-deoxy-[3H]-D-glucose, peroxisome proliferator-activated receptor γ and adiponectin levels, food intake and body weight, GLUT4 mRNA expression and GLUT4 concentration in plasma membranes, as well as homeostasis model assessment-insulin resistance index. Those effects of galanin may be blocked by M817, and imitated by M1145 except for food intake and body weight. CONCLUSION: Those results suggest that central GAL2-R mediates the beneficial effects of galanin on insulin sensitivity in type 2 diabetic rats. GAL2-R agonist may be taken as a potential antidiabetic agent to treat insulin resistance and type 2 diabetes.
PURPOSE: Our and other's studies showed that administration of neuropeptide galanin may mitigate insulin resistance via promoting glucose transporter 4 (GLUT4) expression and translocation in rats. The objective of this study is to investigate whether galanin receptor 2 (GAL2-R) in brain mediates the ameliorative effect of galanin on insulin resistance in adipose tissues of type 2 diabeticrats. METHODS: In this study galanin, GAL2-R agonist M1145 and GAL2-R antagonist M871 were respectively or cooperatively injected into intracerebroventricles of type 2 diabeticrats once a day for successive fifteen days. Then the plasma and fat tissues of rats were used to estimate the alterations of insulin resistance indexes. RESULTS: The central administration of galanin enhanced 2-deoxy-[3H]-D-glucose, peroxisome proliferator-activated receptor γ and adiponectin levels, food intake and body weight, GLUT4 mRNA expression and GLUT4 concentration in plasma membranes, as well as homeostasis model assessment-insulin resistance index. Those effects of galanin may be blocked by M817, and imitated by M1145 except for food intake and body weight. CONCLUSION: Those results suggest that central GAL2-R mediates the beneficial effects of galanin on insulin sensitivity in type 2 diabeticrats. GAL2-R agonist may be taken as a potential antidiabetic agent to treat insulin resistance and type 2 diabetes.
Authors: T S Guillot; J R Richardson; M Z Wang; Y J Li; T N Taylor; B J Ciliax; O Zachrisson; A Mercer; G W Miller Journal: Neuropeptides Date: 2008-06-03 Impact factor: 3.286