Evaluation of differentiation induction of mesenchymal stem cells into pancreatic beta cells by methanolic extract of Medicago sativa L.

β cell replacement therapy by pancreatic islet transplantation has become a promising treatment for type 1 diabetes. Medicago sativa L (Lucerne) from leguminosae family is known to exhibit hypoglycaemic activity both in animal and human studies. Most of these studies were concentrated on the effects of plant extracts on fasting glucose levels. Until now no researches have been carried out to evaluate the potential of this plant on in vitro differentiation of stem cells into pancreatic β cells. The present study was done to examine the possibility of trophic effects of Medicago sativa L. extract (MSE) on differentiation of insulin-producing cells (IPCs) from mesenchymal stem cells (MSCs). Mouse MSCs were isolated and cultured as monolayers. The cells allowed becoming confluent and their identification was confirmed by adipogenic and osteogenic induction tests. In order to induce differentiation of MSCs into IPCs, given concentration of MSE was added to culture medium. Dithizone (DTZ) staining was used to detect IPCs derived from MSCs in vitro. DTZ-positive cells were counted and statistically analyzed using SPSS. Pancreatic β cell-specific proteins were determined by immunofluorescence. MSE treatment had dramatic effects on differentiation of MSC cells into IPCs. Morphological studies using DTZ documented crimson red cell clusters similar to islet. The differentiated cells were immunoreactive for proinsulin, insulin, C-peptide and insulin receptor beta. The results showed that MSE could efficiently induce IPCs differentiation of MSCs. Since, MSC cells are widely available and easily cultured; they would provide a valuable experimental tool for studying pancreatic β cell differentiation.