Hyperinsulinemia may have a protective role in the early stages of atherosclerosis in rabbit model of hypercholesterolemia

Journal of Diabetes & Metabolic Disorders

Nasim Dana²  Azam Feghhi²  Mehdi Nematbakhsh¹  Shaghayegh Haghjooy Javanmard² 

[1] Water and electrolytes research center, Isfahan University of Medical Sciences, Isfahan, Iran;Physiology Research Center, Isfahan University of Medical Sciences, Hezar jarib Avenue, Isfahan, Iran

关键词: Nitric oxide;    C-reactive protein;    Insulin;    Hypercholesterolemia;    Inflammation;   

Others  :  807284
DOI  :  10.1186/2251-6581-11-5

 received in 2012-07-18, accepted in 2012-08-02,  发布年份 2012

【 摘 要 】

Background

Hypercholesterolemia causes inflammation and insulin resistance in the vasculature. Previous data suggest that vascular endothelium is a physiological target of insulin. Dyslipidemia and atherosclerosis are disorders with endothelial dysfunction that are associated with an increased production of superoxide anion, and early deficit of nitric oxide (NO) production. We examined alteration of plasma levels of insulin, C-reactive protein (CRP) and total NO metabolites (NOx), as well as fatty streak formation in the rabbit model of hypercholesterolemia.

Methods

White male rabbits were fed either a high-cholesterol diet (HC; 1% cholesterol, n = 6) or control diet (c, n = 6) for one month. The serum levels of Cholesterol, LDL, HDL, NOx, insulin and CRP were measured before and after study. By the end of study, rabbits' aorta was explored for fatty streak formation.

Results

The cholesterol-rich diet induced a significant increase in total cholesterol, LDL, and HDL as well as fatty streak lesions in HC group while there were no significant changes of these parameters in control group (p <0.05). There was significant difference in plasma levels of CRP, insulin and total NO metabolite between two groups of experiment. Negative significant correlation of CRP and insulin also was observed in HC rabbits (r = −0.99, p <0.05).

Conclusion

Parallel NOx and insulin increment and negative correlation of CRP and insulin in HC rabbits may be suggestive a protective role of hyperinsulinemia in early atherosclerosis.

【 授权许可】

   
2012 Javanmard et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1 .

Figure 2 .

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