Taurine supplementation reduces blood pressure and prevents endothelial dysfunction and oxidative stress in post-weaning protein-restricted rats

PLoS One. 2014 Aug 29;9(8):e105851. doi: 10.1371/journal.pone.0105851. eCollection 2014.

Abstract

Introduction: Taurine is a sulfur-containing amino acid that exerts protective effects on vascular function and structure in several models of cardiovascular diseases through its antioxidant and anti-inflammatory properties. Early protein malnutrition reprograms the cardiovascular system and is linked to hypertension in adulthood. This study assessed the effects of taurine supplementation in vascular alterations induced by protein restriction in post-weaning rats.

Methods and results: Weaned male Wistar rats were fed normal- (12%, NP) or low-protein (6%, LP) diets for 90 days. Half of the NP and LP rats concomitantly received 2.5% taurine supplementation in the drinking water (NPT and LPT, respectively). LP rats showed elevated systolic, diastolic and mean arterial blood pressure versus NP rats; taurine supplementation partially prevented this increase. There was a reduced relaxation response to acetylcholine in isolated thoracic aortic rings from the LP group that was reversed by superoxide dismutase (SOD) or apocynin incubation. Protein expression of p47phox NADPH oxidase subunit was enhanced, whereas extracellular (EC)-SOD and endothelial nitric oxide synthase phosphorylation at Ser 1177 (p-eNOS) were reduced in aortas from LP rats. Furthermore, ROS production was enhanced while acetylcholine-induced NO release was reduced in aortas from the LP group. Taurine supplementation improved the relaxation response to acetylcholine and eNOS-derived NO production, increased EC-SOD and p-eNOS protein expression, as well as reduced ROS generation and p47phox expression in the aortas from LPT rats. LP rats showed an increased aortic wall/lumen ratio and taurine prevented this remodeling through a reduction in wall media thickness.

Conclusion: Our data indicate a protective role of taurine supplementation on the high blood pressure, endothelial dysfunction and vascular remodeling induced by post-weaning protein restriction. The beneficial vascular effect of taurine was associated with restoration of vascular redox homeostasis and improvement of NO bioavailability.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetophenones / pharmacology
  • Acetylcholine / pharmacology
  • Animals
  • Aorta, Thoracic / drug effects
  • Aorta, Thoracic / physiology
  • Blood Pressure / drug effects*
  • Blotting, Western
  • Diet, Protein-Restricted*
  • Dietary Supplements*
  • Endothelium, Vascular / drug effects*
  • Endothelium, Vascular / metabolism
  • Endothelium, Vascular / physiopathology
  • Heart Rate / drug effects
  • In Vitro Techniques
  • Male
  • NADPH Oxidases / metabolism
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase Type III / metabolism
  • Oxidative Stress / drug effects*
  • Rats, Wistar
  • Reactive Oxygen Species / metabolism
  • Superoxide Dismutase / metabolism
  • Superoxide Dismutase / pharmacology
  • Taurine / administration & dosage
  • Taurine / pharmacology*
  • Vasodilation / drug effects
  • Vasodilator Agents / pharmacology
  • Weaning

Substances

  • Acetophenones
  • Reactive Oxygen Species
  • Vasodilator Agents
  • Taurine
  • Nitric Oxide
  • acetovanillone
  • Nitric Oxide Synthase Type III
  • Superoxide Dismutase
  • NADPH Oxidases
  • neutrophil cytosolic factor 1
  • Acetylcholine

Grant support

This work (data collection and analysis) was supported by grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP). EMC is a research fellow from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.