Preventive and Therapeutic Potentials of Anthocyanins in Diabetes and Associated Complications.

Diet is an essential factor affecting the development of and risk for diabetes mellitus. In search of preventative and therapeutic strategies, the potential role of certain foods and their bioactive compounds to prevent the pathogenesis associated with metabolic diseases is to be considered. Human consumption of anthocyanins is among the highest of all flavonoids. Epidemiological studies have suggested that the consumption of anthocyanins lowers the risk of diabetes and diabetic complications. Anthocyanins are important natural bioactive pigments responsible for red to blue colour of fruits, leaves, seeds, stems and flowers, which are present in a variety of plant species particularly in berries and cherries. A large number of bioactive anthocyanins, such as cyanidin, malvidin, delphinidin, pelargonidin, peonidin, petunidin and their metabolites have shown multiple biological activities with apparent effects on glucose absorption, glucose uptake, insulin secretion and sensitivity, on the enzymes involved in glucose metabolism, gene expressions, inflammatory mediators, glucose transporters in progression of diabetes and associated complications, such as diabetic retinopathy, nephropathy, neuropathy and diabetic vascular diseases. The versatility of the anthocyanins provides a promising approach for diabetes management than synthetic drugs. Here we summarize the effect of several anthocyanins on many in vitro, in vivo and clinical studies and also reveal the mechanisms which could prevent or reverse the underlying mechanisms of diabetic pathologies including promotion of antioxidant, antihyperlipidemic, anti-inflammatory and anti-apoptotic activities.

Influence of selenium (antioxidant) on gliclazide induced hypoglycaemia/anti hyperglycaemia in normal/alloxan-induced diabetic rats.

Oxidative stress is involved in diabetes mellitus and its complications. Since diabetes is a stress-related disorder, supplementation with antioxidants may improve the condition. The purpose of this study is to know the effect of oral administration of selenium on blood glucose and its influence on gliclazide induced hypoglycaemia/antihyperglycaemia in normal and alloxan-induced diabetic rats. Albino rats of either sex were divided into three groups of six each. Group-I/II/III were treated with selenium 1/2 TD (0.9 microg/200 g rat)/TD (1.8 microg/200 g rat)/2TD (3.6 microg/200 g rat), respectively. Later group II was treated with gliclazide TD (1.44 mg/200 g rat)/selenium TD + gliclazide TD with a washout period of 1 week between the treatments. Diabetes was induced by alloxan monohydrate 100 mg/kg body weight i.p. A group of six rats showing fasting blood glucose levels ranging from 175-250 mg/dl were selected for the study. Rats were treated with selenium TD, gliclazide TD and selenium TD + gliclazide TD with a washout period of 1 week between the treatments. Selenium 1/2 TD and TD produced hypoglycaemia while 2TD produced hyperglycaemia. The combination of selenium TD with gliclazide TD, significantly enhanced the glucose lowering effect of gliclazide in normal and diabetic rats.