[Metformin effect on the mouse pancreatic langerhans islets volume]

Metformin is a widely used medicine for treatment of type 2 diabetes. In this study, the effect of various doses of metformin on the mouse islets of langerhans volume was investigated. Twenty four C57BL/6 adult male mice weighting 30 +/- 5 gr were randomly divided into 4 groups. Normal saline was given to the control group [group 4] and the experimental groups [groups 1-3] received 75, 150 and 300 mg/kg metformin daily by intraperitoneal injection for seven days. One day after the last injection the mice were sacrificed by cervical dislocation and their pancreases were fixed in 10% formalin for histological studies. The volume of the islets of langerhans was estimated by using Cavalieri method. Volume of the islets of langerhans in doses of 75 and 150 mg/kg Metformin showed a nonsignificant difference in comparison to control group [P>0.05]. 300 mg/kg metformin treated mice showed a significant increase in islets of langerhans volume compared to the control group [P<0.05]. Metformin increases in the islets of langerhans volume in a dose-dependent manner. Increasing effects of Metformin on the islets of langerhans volume may be due to proliferation or hypertrophy of beta cells

[Effect of metformin on the Pdx-1 gene expression during development of mouse pancreas]

Metformin, an oral medicine used to treat type 2 diabetes, is a Glucagon-Like Peptide-1 [GLP-1] analogue, which has been demonstrated to stimulate the expression of Pancreatic duodenal homeobox-1 [Pdx-1], Insulin and Glucose transporter 2 [Glut-2] genes. In this study, the regulatory effect of metformin on beta cells function through the expression of Pdx-1, Insulin and Glut-2 genes was investigated. Pregnant C57BL/6 mice were randomly divided into 2 groups. Normal saline was given to the control group and the experimental group received 75, 150 and 250 mg/kg metformin daily by intraperitoneal injection from day 8.5 of pregnancy. Half the pregnant animals were then sacrificed by cervical dislocation or day 19.5 of pregnancy and the pancreases of embryos were dissected. The other half of pregnant animals were allowed to deliver their pups and the pancreases of one day old mice were dissected. The dissected pancreases were then used for assessment of Pdx-1, Insulin and Glut-2 genes expression by semi-quantitative RT-PCR method. Results showed that the administration of various doses of metformin caused no changes in the expression of Pdx-1, Insulin and Glut-2 genes compared to the control group [P>0.05]. The regulatory effect of metformin on beta cells function might not be related to the expression of Pdx-1, Insulin and Glut-2 genes and may be related to the expression of gloconeogenesis pathway genes