Salacia – The new multi-targeted approach in diabetics

Salacia species plant has been used traditionally as an Ayurvedic medicine for diabetes mellitus. Studies over the past decades have shown its multi-targeted role in diabetics. In the present review article, various mechanisms of action of Salacia on diabetics are discussed in detail. Apart from the well-known action of decreasing postprandial glucose sugar by inhibiting α-glucosidase and α-pancreatic amylase, it also inhibits aldose reductase which otherwise results in microvascular complications. Importantly, its peroxisome proliferator-activated receptor (PPAR)-γ agonist (such as thiazolidinediones, the insulin sensitizers) action increases the uptake of free fatty acid (FFA) and facilitates their storage in subcutaneous fat rather than the visceral fat. This reduces plasma FFA and insulin resistance. Furthermore, it increases the expression of and translocation to the cell surface of glucose transporter 1 and 4 receptors which result in glucose uptake by the liver and skeletal muscle and decreases plasma glucose levels. It also decreases inflammatory cytokines and increases adiponectin expression. Salacia as PPAR-α agonist (such as fibrates) has a role in the management of dyslipidemia. The activation of PPAR-α leads to the increased expression of lipoprotein lipase and apolipoprotein (Apo) A-V and decrease in hepatic Apo-C-III. These actions lower plasma triglycerides in chylomicrons and very low-density lipoprotein particles, thus liberating fatty acids, which are taken up and stored as fat in adipocytes. Salacia has been shown to suppress the overexpression of cardiac PPAR-α (similar to angiotensin-converting enzyme inhibitors/angiotensin receptor blockers) and thereby preventing diabetic cardiomyopathy. It also suppresses the cardiac angiotensin II Type 1 receptors resulting in antihypertrophic and antifibrogenic effect.