Anti-inflammatory properties of BHUx, a polyherbal formulation to prevent atherosclerosis

BHUx is a polyherbal formulation consisting of water-soluble fractions of five medicinal plants ( Commiphora mukul , Terminalia arjuna , Boswellia serrata , Semecarpus anacardium and Strychnos nux vomica ). The present study was undertaken to evaluate its antioxidant and anti-inflammatory effects. BHUx, standardized by HPLC fingerprinting and filtered through 0.2 μ m filter paper, was employed for different studies under in vivo and in vitro conditions. Under in vivo conditions, BHUx significantly reduced inflammation in the carrageenan-induced rat paw oedema model of inflammation, suggesting its anti-inflammatory properties. In order to test the mechanism of action of BHUx, further in vitro studies were undertaken on cumene-hydroperoxide-induced lipid peroxidation (CHP) in liver homogenate, LPS-induced NO production in peritoneal macrophages and on key enzymes of arachidonic acid cascade, involved in the mediation of inflammation. Under the conditions, BHUx showed concentration-dependent inhibition of CHP-induced lipid peroxidation in liver homogenate, suggesting its antioxidant properties. Similarly the potent anti-inflammatory effects of BHUx are evident by (a) preferential inhibition of COX-2 (IC 50 for COX-2 = 80 μ g/ml and IC 50 for COX-1 = 169 μ g/ml), (b) low ratios in the IC 50 values of COX-2/COX-1 (0.47), (c) decreased production of NO in LPS-induced peritoneal macrophages and (d) inhibition of 5-LOX (IC 50 = 795 μ g/ml). BHUx also showed a preference for inhibiting 15-lipoxygenase (IC 50 = 44 μ g/ml), a key enzyme implicated in LDL oxidation. These studies suggest that BHUx is acting mainly at three levels, i.e., as a potent natural antioxidant, by reduction of key inflammatory mediators of arachidonic acid cascade and by preventing 15-LOX-mediated LDL oxidations, to prevent atherosclerosis.