Up Regulation of cystathione γ lyase and Hydrogen Sulphide in the Myocardium Inhibits the Progression of Isoproterenol-Caffeine Induced Left Ventricular Hypertrophy in Wistar Kyoto Rats.

Ashfaq Ahmad,Munavvar A Sattar,Mohammed H Abdulla,Safia A Khan,Edward J Johns,Maleeha Azam,Hassaan A Rathore,Nor A Abdullah

doi:10.1371/journal.pone.0150137

Abstract

Hydrogen sulphide (H2S) is an emerging molecule in many cardiovascular complications but its role in left ventricular hypertrophy (LVH) is unknown. The present study explored the effect of exogenous H2S administration in the regression of LVH by modulating oxidative stress, arterial stiffness and expression of cystathione γ lyase (CSE) in the myocardium. Animals were divided into four groups: Control, LVH, Control-H2S and LVH-H2S. LVH was induced by administering isoprenaline (5mg/kg, every 72 hours, S/C) and caffeine in drinking water (62mg/L) for 2 weeks. Intraperitoneal NaHS, 56μM/kg/day for 5 weeks, was given as an H2S donor. Myocardial expression of Cystathione γ lyase (CSE) mRNA was quantified using real time polymerase chain reaction (qPCR).There was a 3 fold reduction in the expression of myocardial CSE mRNA in LVH but it was up regulated by 7 and 4 fold in the Control-H2S and LVH-H2S myocardium, respectively. Systolic blood pressure, mean arterial pressure, pulse wave velocity were reduced (all P<0.05) in LVH-H2S when compared to the LVH group. Heart, LV weight, myocardial thickness were reduced while LV internal diameter was increased (all P<0.05) in the LVH-H2S when compared to the LVH group. Exogenous administration of H2S in LVH increased superoxide dismutase, glutathione and total antioxidant capacity but significantly reduced (all P<0.05) plasma malanodialdehyde in the LVH-H2S compared to the LVH group. The renal cortical blood perfusion increased by 40% in LVH-H2S as compared to the LVH group. Exogenous administration of H2S suppressed the progression of LVH which was associated with an up regulation of myocardial CSE mRNA/ H2S and a reduction in pulse wave velocity with a blunting of systemic hemodynamic. This CSE/H2S pathway exhibits an antihypertrophic role by antagonizing the hypertrophic actions of angiotensin II(Ang II) and noradrenaline (NA) but attenuates oxidative stress and improves pulse wave velocity which helps to suppress LVH. Exogenous administration of H2S augmented the reduced renal cortical blood perfusion in the LVH state.

Highlights

Left ventricular hypertrophy (LVH) is a compensatory response of the heart against the elevated after load to maintain the ejection fraction
The present study explored the hypothesis that in left ventricular hypertrophy there would be a down regulation of cystathione γ lyase (CSE) mRNA in the heart with increased oxidative stress in the systemic circulation.We hypothesized that exogenous administration of H2S would up regulate cardiac CSE associated with an attenuation of physical indices, as an antihypertophic agent on one doi:10.1371/journal.pone.0150137.g004
Exogenous administration of H2S up regulated CSE mRNA expression in the heart and suppressed the progression of left ventricular hypertrophy associated with a corresponding increase in H2S concentrations in the myocardium and plasma

Summary

Introduction

Left ventricular hypertrophy (LVH) is a compensatory response of the heart against the elevated after load to maintain the ejection fraction. Persistent elevated hypertrophy progresses to dilation of the heart and decreased ejection fraction which leads to heart failure [1]. Elevated blood pressure and LVH have been found to be surrogate markers of each other in many studies [4,5,6] and spontaneously hypertensive rats (SHR) have been used as model of LVH [7]. Hydrogen sulphide (H2S) has been reported to modulate vascular tone [14]and has a cardio protective role [15]. Oxidative stress is considered to play a major contribution in the pathogenesis of LV remodelling [16,17,18]. H2S has an antioxidant role by suppressing NAPH oxidase [19], scavenging lipid peroxides [20, 21], potentiating catalase and superoxide dismutase while up regulating GSH [22] in the brain and endothelial cells which may play a therapeutic role in many diseased conditions where the suppression of oxidative stress is required

Methods

Results

Discussion

Conclusion