In Vivo Effects of Quercetin in Association with Moderate Exercise Training in Improving Streptozotocin-Induced Aortic Tissue Injuries

Molecules. 2015 Dec 4;20(12):21770-86. doi: 10.3390/molecules201219802.

Abstract

Background: Diabetes mellitus (DM) is a chronic endocrine-metabolic disorder associated with endothelial dysfunction. Hyperglycemia, dyslipidemia and abnormal nitric oxide-mediated vasodilatation are the major causal factors in the development of endothelial dysfunction in DM. The prevention of endothelial dysfunction may be a first target against the appearance of atherosclerosis and cardiovascular diseases. We have investigated the synergistic protective effects of quercetin administration and moderate exercise training on thoracic aorta injuries induced by diabetes.

Methods: Diabetic rats that performed exercise training were subjected to a swimming training program (1 h/day, 5 days/week, 4 weeks). The diabetic rats received quercetin (30 mg/kg body weight/day) for 4 weeks. At the end of the study, the thoracic aorta was isolated and divided into two parts; one part was immersed in 10% formalin for histopathological evaluations and the other was frozen for the assessment of oxidative stress markers (malondialdehyde, MDA and protein carbonyls groups, PC), the activity of antioxidant enzymes (superoxide dismutase, SOD and catalase, CAT), nitrite plus nitrate (NOx) production and inducible nitric oxide synthase (iNOS) protein expression.

Results: Diabetic rats showed significantly increased MDA and PC levels, NOx production and iNOS expression and a reduction of SOD and CAT activity in aortic tissues. A decrease in the levels of oxidative stress markers, NOx production and iNOS expression associated with elevated activity of antioxidant enzymes in the aortic tissue were observed in quercetin-treated diabetic trained rats.

Conclusions: These findings suggest that quercetin administration in association with moderate exercise training reduces vascular complications and tissue injuries induced by diabetes in rat aorta by decreasing oxidative stress and restoring NO bioavailability.

Keywords: diabetes mellitus; endothelial dysfunction; exercise training; quercetin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / pharmacology
  • Antioxidants / therapeutic use*
  • Aorta, Thoracic / drug effects
  • Aorta, Thoracic / pathology
  • Blood Glucose
  • Cholesterol / blood
  • Diabetes Mellitus, Experimental / blood
  • Diabetes Mellitus, Experimental / chemically induced
  • Diabetes Mellitus, Experimental / complications*
  • Diabetic Angiopathies / blood
  • Diabetic Angiopathies / therapy*
  • Drug Evaluation, Preclinical
  • Exercise Therapy
  • Male
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase Type II / metabolism
  • Oxidative Stress
  • Quercetin / pharmacology
  • Quercetin / therapeutic use*
  • Rats, Wistar
  • Streptozocin
  • Swimming
  • Triglycerides / blood

Substances

  • Antioxidants
  • Blood Glucose
  • Triglycerides
  • Nitric Oxide
  • Streptozocin
  • Cholesterol
  • Quercetin
  • Nitric Oxide Synthase Type II
  • Nos2 protein, rat