Increased insulin and GLUT2 gene expression and elevated glucokinase activity in ß-like cells of islets of langerhans differentiated from human haematopoietic stem cells on treatment with Costus igneus leaf extract.

ABSTRACT

In the quest to understand lost ß-cells regeneration in the diabetic condition, we have demonstrated successful differentiation of human haematopoietic stem cells (HSCs) to functional ß-like cells. Costus igneus (Ci) leaf extract is known to exhibit anti-diabetic properties by lowering the blood glucose level as demonstrated in mice models. To establish the anti-diabetic properties of Ci leaf extract on human subjects, we studied the effect of Ci on these differentiated ß-like cells. Ci leaf extract showed its anti-diabetic property through elevated glucokinase activity which catalyzes the rate-limiting step of glucose catabolism in ß-like cells and acts as a sensor for insulin production while decreasing the glucose-6-phosphatase activity. Upon increasing the concentrations of Ci leaf extract (25, 65, 105, 145, 185 µg/ml) and glucose concentrations (5.5, 11.1, and 25 mM) Ci leaf extract treated ß-like cells showed enhanced glucokinase and decreased glucose-6-phosphatase activities and an exponential rise in gene expressions of INS and GLUT2 was observed. The present study shows enhanced INS and GLUT2 gene expression and elevated glucokinase activity in ß-like cells differentiated from HSCs upon treatment with Ci leaf extract explain the anti-diabetic property of Ci leaf extract. This extract can be effectively used in the management of diabetes.