A review of α-amylase inhibitors on weight loss and glycemic control in pathological state such as obesity and diabetes

Overweight, obesity, and diabetes are the most common disorders in the world. In most diets, carbohydrates are the greatest source of calories. Inhibition of carbohydrate digestion or absorption can decrease calorie intake to promote weight loss and combat obesity. It is also a mechanism for reducing hyperglycemia in diabetic subjects. Before being absorbed by the body, carbohydrates must be broken down into monosaccharides. α-Amylase catalyzes the hydrolysis of α-(1,4)-d-glycosidic linkages of starch and other glucose polymers. Inhibitors of this enzyme can be used in treatment of obesity and diabetes. In diabetic patients, inhibition of α-amylase leads to prohibition starch breaking and results in lower levels of blood glucose. The effects of pseudosaccharides, proteinaceous, and polyphenolic inhibitors have been previously reported. Polyphenolic compounds are widely distributed in plants and fruits and are present in normal diets. These compounds have been shown to possess beneficial effects in diabetes, cardiovascular diseases, atherosclerosis, allergy, inflammation, and osteoporosis. Among polyphenolic compounds, flavonoids are of particular significance: They have been shown to reduce cholesterol synthesis via direct action on HMG-CoA reductase and hydrolyze lipids via inhibition of phosphodiesterase (PDE) and diminution of cAMP breakdown. In recent years, many lines of research have been done on those plants which are being used traditionally as drug plants, and their effects have been surveyed on weight loss and control of blood glucose levels in diabetic patients. In this review, we want to investigate α-amylase inhibitors especially human pancreatic α-amylase (HPA)