Effect of total extract of Urtica dioica on insulin and C-peptide secretion from rat (RIN5F) pancreatic ? cells and glucose utilization by human muscle cells

Abstract

Introduction: The hypoglycemic effects of the Uritca Dioica (UD) extract, used for treatment of diabetes mellitus for many centuries, have been documented in several studies. The present study was designed to determine the possible mechanisms of hypoglycemic effects of UD on human muscle cells and RIN5F rat pancreatic ? cells. Materials and Methods: In the cell culture laboratory of the Drug Applied Research Center, pancreatic ? cells and human muscle cells were prepared in multiple flasks containing culture media. Alcoholic extract of UD at concentrations of 50, 100 and 200 ?g/mL were added to muscle cell flasks. The same concentrations of extract plus insulin were added to other muscle cell flasks. Glucose levels were measured in the flasks before and after 60, 120 and 180 minutes after adding of extract. Also the same concentrations of UD were added to flask containing RIN5F rat pancreatic ? cells, and insulin and C-peptide level were measured at 0, 60, 120 and 180 minutes. Results: Mean glucose level in the muscle cell media with UD alone and UD plus insulin, at the concentrations and time intervals mentioned, did not change significantly. Insulin levels in pancreatic cells media, before and after applying of UD at different concentrations, and at different times was ?0.2 ?g/ml. C-peptide (?g/ml) levels in these medias with a dose of 50 ?g/ml of UD and at above mentioned times were 0.31, 0.33, 0.86 and 0.8; at concentration of 100 ?g/mL they were 0.7, 0.2, 0.4 and 0.39, and at concentration of 200 ?g/mL were 0.32, 0.33, 0.93, 0.77 respectively (Nonsignificant changes). Conclusion: The results of the present study showed that alcoholic extract of UD was unable to increase insulin sensitivity in muscle cells and/or increase insulin and C-peptide secretion from RIN5F pancreatic ? cells. It seems that hypoglycemic effects of UD were not mediated through the proposed mechanisms of this study.