Effects and mechanisms of berberine in diabetes treatment

Berberine from Rhizoma Coptidis is an oral hypoglycemic agent with anti-dyslipidemia and anti-obesity activities. Its metabolic activity of regulating blood glucose and lipids has been widely studied and evidenced in patients and various animal models. Berberine is known as an AMP-activated protein kinase (AMPK) activator. Its insulin-independent hypoglycemic effect is related to inhibition of mitochondrial function, stimulation of glycolysis and activation of AMPK pathway. Additionally, berberine may also act as an cc-glucosidase inhibitor. In the newly diagnosed type 2 diabetic patients, berberine is able to lower blood insulin level via enhancing insulin sensitivity. However, in patients with poor beta-cell function, berberine may improve insulin secretion via resuscitating exhausted islets. Furthermore, berberine may have extra beneficial effects on diabetic cardiovascular complications due to its cholesterol-lowering, anti-arrhythmias and nitric oxide (NO) inducing properties. The antioxidant and aldose reductase inhibitory activities of berberine may be useful in alleviating diabetic nephropathy. Although evidence from animal and human studies consistently supports the therapeutic activities of berberine, large-scale multicenter trials are still necessary to evaluate the efficacy of berberine on diabetes and its related complications. (C) 2012 Institute of Materia Medica, Chinese Academy of Medical Sciences and Chinese Pharmaceutical Association. Production and hosting by Elsevier B.V. All rights reserved.