Atorvastatin protects against aorta contractility impairment in insulin‐resistant rats

Abstract

This study aimed to investigate the possible protective role of atorvastatin against the vascular dysfunction associated with insulin resistance (IR) in high fructose‐fed rats. In the pursuit of this aim, blood levels of glucose, cholesterol, insulin as well as vascular reactivity and insulin resistance index were assessed in a well‐established model of insulin resistance in presence or absence of atorvastatin (10 mg/kg/day for 8 weeks). Fructose feeding (10% fructose in drinking water for 8 weeks) induced hypercholesterolemia, hyperinsulinemia without any change in blood glucose level. Additionaly, serum tumor necrosis factor (TNF‐α), insulin resistance index, leukocyte infiltration of aorta and endothelial cell pyknosis were elevated. Fructose feeding induced hyperresponsiveness to both phenylephrine (PE) and KCl and hyporesponsiveness to ACh but not to sodium nitroprusside (SNP) relaxations. Most importantly, in atorvastatin‐treated rats, blood levels of cholesterol, insulin and TNF‐α, in addition to insulin resistance index were significantly reduced. Furthermore, atorvastatin treatment reduced leukocyte infiltration and endothelial cell pyknosis and decreased the hyperresponsiveness to both phenylephrine and KCl. In conclusion, the current study highlights a protective role for atorvastatin against the impairment in aortic vascular reactivity via a mechanism that involves reduction of the elevated cholesterol and TNF‐α levels in insulin resistance rats.