Pharmacologically Active Phytomolecules Isolated from Traditional Antidiabetic Plants and Their Therapeutic Role for the Management of Diabetes Mellitus.

Diabetes mellitus is a chronic complication that affects people of all ages. The increased prevalence of diabetes worldwide has led to the development of several synthetic drugs to tackle this health problem. Such drugs, although effective as antihyperglycemic agents, are accompanied by various side effects, costly, and inaccessible to the majority of people living in underdeveloped countries. Medicinal plants have been used traditionally throughout the ages to treat various ailments due to their availability and safe nature. Medicinal plants are a rich source of phytochemicals that possess several health benefits. As diabetes continues to become prevalent, health care practitioners are considering plant-based medicines as a potential source of antidiabetic drugs due to their high potency and fewer side effects. To better understand the mechanism of action of medicinal plants, their active phytoconstituents are being isolated and investigated thoroughly. In this review article, we have focused on pharmacologically active phytomolecules isolated from medicinal plants presenting antidiabetic activity and the role they play in the treatment and management of diabetes. These natural compounds may represent as good candidates for a novel therapeutic approach and/or effective and alternative therapies for diabetes.

Insulin secretory actions of ethanolic extract of Acacia arabica bark in high fat-fed diet-induced obese Type 2 diabetic rats.

Acacia arabica commonly known as 'babul' has been widely used for the treatment of numerous diseases, including diabetes due to their potential pharmacological actions. The aim of the present study was to investigate the insulinotropic and antidiabetic properties of ethanol extract of Acacia arabica (EEAA) bark through in vitro and in vivo studies in high fat-fed (HFF) rats. EEAA at 40-5000 µg/ml significantly increased (P<0.05-0.001) insulin secretion with 5.6 and 16.7 mM glucose, respectively, from clonal pancreatic BRIN BD11 ß-cells. Similarly, EEAA at 10-40 µg/ml demonstrated a substantial (P<0.05-0.001) insulin secretory effect with 16.7 mM glucose from isolated mouse islets, with a magnitude comparable to 1 µM glucagon-like peptide-1 (GLP-1). Diazoxide, verapamil, and calcium-free conditions decreased insulin secretion by 25-26%. The insulin secretory effect was further potentiated (P<0.05-0.01) with 200 µM isobutylmethylxanthine (IBMX; 1.5-fold), 200 µM tolbutamide (1.4-fold), and 30 mM KCl (1.4-fold). EEAA at 40 µg/ml, induced membrane depolarization and elevated intracellular Ca2+ as well as increased (P<0.05-0.001) glucose uptake in 3T3L1 cells and inhibited starch digestion, glucose diffusion, dipeptidyl peptidase-IV (DPP-IV) enzyme activity, and protein glycation by 15-38%, 11-29%, 15-64%, and 21-38% (P<0.05, 0.001), respectively. In HFF rats, EEAA (250 mg/5 ml/kg) improved glucose tolerance, plasma insulin, and GLP-1 levels, and lowered DPP-IV enzyme activity. Phytochemical screening of EEAA revealed the presence of flavonoids, tannins and anthraquinone. These naturally occurring phytoconstituents may contribute to the potential antidiabetic actions of EEAA. Thus, our finding suggests that EEAA, as a good source of antidiabetic constituents, would be beneficial for Type 2 diabetes patients.