a1 Agroprocessing and Natural Products Division, Council of Scientific and Industrial Research-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Pappanamcode, Trivandrum 695 019, Kerala, India
a2 Department of Biochemistry, University of Kerala, Kariavattom Campus, Trivandrum 695 581, Kerala, India
The present study evaluated the antihypertrophic potential of the ethanolic extract of Boerhaavia diffusa (BDE), a well-known edible cardiotonic plant reported in Ayurveda against angiotensin II-induced hypertrophy in H9c2 cardiac myoblast cells. Markers of hypertrophy such as cell size, protein content and the concentrations of atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) were analysed for the confirmation of hypertrophy induction. Angiotensin II (100 nm) caused an increase in cell volume (69·26 (sd 1·21) %), protein content (48·48 (sd 1·64) %), ANP (81·90 (sd 1·22) %) and BNP (108·57 (sd 1·47) %). BDE treatment significantly reduced cell volume, protein content and the concentrations of ANP and BNP (P≤ 0·05) in H9c2 cells. The activity of various antioxidant enzymes and the concentration of reduced glutathione, which was lowered due to hypertrophy, were increased in BDE-treated cells. The BDE treatment also reduced intracellular reactive oxygen species generation, lipid peroxidation and protein carbonyls in cells. In addition, the expression patterns of NF-κβ and transforming growth factor β1 were found to be increased during hypertrophy, and their expressions were reduced on BDE treatment. In vitro chemical assays showed that BDE inhibits angiotensin-converting enzyme and xanthine oxidase in a dose-dependent manner with an estimated 50 % effective concentration (EC50) value of 166·12 (sd 2·42) and 60·05 (sd 1·54) μg/ml, respectively. The overall results clearly indicate the therapeutic potential of B. diffusa against cardiac hypertrophy, in addition to its nutritional qualities.
(Received July 17 2012)
(Revised January 29 2013)
(Accepted January 29 2013)
(Online publication April 16 2013)
Abbreviations: ACE, angiotensin-converting enzyme; ANP, atrial natriuretic peptide; BDE, Boerhaavia diffusa extract; BNP, B-type natriuretic peptide; GSH, reduced glutathione; LDH, lactate dehydrogenase; ROS, reactive oxygen species; TBARS, thiobarbituric acid-reactive substances; TGF-β1, transforming growth factor β1; TPC, total phenolic content; XO, xanthine oxidase