LM long-term treatment reduces plasma HbA1c, increases serum insulin and improves insulin release. Blood samples were collected during the OGTT performed on day 0, 10 and 20 to measure plasma HbA1c in GK rats (A) and in W rats (B) (n = 6). Serum insulin was measured at 0 and 30 min during the OGTT; GK rats (C) and W rats (D) (n = 6). Pancreatic islets isolated from GK rats (E) and Wistar rats (F) at the end point of treatment were incubated in low (3.3 mM) and high (16.7 mM) glucose. Insulin concentration was measured by RIA. The data are presented as means ± SE, * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001 when compared to placebo group and ####
p < 0.0001 when compared to same group values at different days of treatment.