Evaluation of hypoglycemic activity of the leaves of Malva parviflora in streptozotocin-induced diabetic rats

Malva parviflora (MP), known in Mexico by the name of "quesitos" or "malva", is popular due to its culinary and medicinal properties. Diabetic rats were treated with the hexane, chloroform and methanol extracts of the M. parviflora leaves for 28 days and a set of biochemical parameters were studied including: glucose level, total cholesterol, triglycerides, lipid peroxidation, liver and muscle glycogen, superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase. We also looked into liver function by determining glucose-6-phosphatase, glucokinase and hexokinase activities, and the effect of the extracts on insulin level and protein glycation. As a result we found that with the hexane extract the blood glucose level, serum biochemical parameters, hepatic enzymes, thiobarbituric acid reactive substances, glycosylated hemoglobin, advanced glycation end products, and insulin level were restored in streptozotocin induced diabetic rats to nearly normal levels. We conclude that the hexane extract of M. parviflora leaves can efficiently inhibit insulin resistance, lipid abnormalities and oxidative stress, indicating that its therapeutic properties may be due to the interaction plant components soluble in the hexane extract, with any of the multiple targets involved in diabetes pathogenesis.