ABSTRACT
In this study, we studied whether chronic oral administration of the natural antioxidant, malabaricone C (mal C) can reduce blood pressure (BP) and attenuate cardio-vascular remodeling in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. The dose of mal C for its anti-hypertensive action was optimized by measuring the systolic BP (SBP). DOCA-salt rats showed very high SBP, associated with organ hypertrophy, collagen depositions, and inflammatory infiltrations in cardiac and aortic sections, reduced plasma total antioxidant status and NO level, and increased levels of TBARS, PGI2 as well as vasoconstrictors (AVP, Big ET, and ET-1). DOCA-salt also reduced smooth muscle- and endothelium-dependent vascular relaxation in rats. Mal C reversed all these changes of the DOCA-salt rats and improved their vascular reactivity. Mal C exerts anti-hypertensive property in DOCA-salt rats by reducing oxidative stress and organ hypertrophy, and improving endothelial and vascular functions. Given that mal C has appreciable natural abundance and is non-toxic to rodents, further studies would help in establishing its medicinal potential against hypertension.
Subject(s)
Antihypertensive Agents/therapeutic use , Hypertension/drug therapy , Resorcinols/therapeutic use , Animals , Antioxidants/pharmacology , Aorta/drug effects , Aorta/pathology , Desoxycorticosterone Acetate , Disease Models, Animal , Heart/drug effects , Hypertension/chemically induced , Hypertrophy/drug therapy , Male , Myocardium/pathology , Oxidative Stress/drug effects , Rats , Vasodilation/drug effectsABSTRACT
The 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay of the ethanol extracts of three varieties (Bangla, sweet, and Mysore) of Piper betel (pan) revealed the Bangla variety to possess the best antioxidant activity that can be correlated with the total phenolic content and reducing powers of the respective extracts. Column chromatography of the extract of the Bangla variety led to the isolation of chevibetol (CHV), allylpyrocatechol (APC), and their respective glucosides. The HPTLC analyses of the extracts revealed similar chemical profiles in all three P. betel varieties, although the concentrations of CHV and APC were significantly less in the sweet and Mysore varieties. Among the isolated compounds, APC showed the best results in all the in vitro experiments. It could prevent Fe(II)-induced lipid peroxidation (LPO) of liposomes and rat brain homogenates as well as gamma-ray-induced damage of pBR322 plasmid DNA more efficiently than CHV. The superior anti-LPO and radioprotective activities of APC vis-à-vis those of CHV could not be explained by their respective Fe(II) chelation and .OH radical scavenging capacities. The better ability of APC to scavenge O2-. radicals and H2O2 might account for the results.
