Systemic administration of ghrelin did not restore angiogenesis in hindlimb ischemia in control and diet-induced obese mice.

Abstract

Ghrelin is a novel growth hormone releasing peptide that mainly regulates food intake and energy homeostasis, however, recently, it is indicated that it may be closely related with physiological and/or pathological angiogenesis. The objective of the present study was to evaluate the effect of systemic ghrelin administration on angiogenesis in hindlimb ischemia in normal and diet-induced obese mice. 24 male C57BL/6 mice were fed with high-fat diet (HFD) or standard for 14 weeks. Then, the mice underwent unilateral hindlimb ischemia. Next, each group was divided into the two subgroups: treatment with ghrelin (100 µg/kg, twice daily, Sc) or without treatment. After 10 days, the animals were sacrificed, blood samples were taken and the gastrocnemius muscles removed. There was no significant difference in capillary/fiber ratio in hind limb ischemia between obese and control groups. Administration of ghrelin reduced serum nitric oxide (NO) and leptin and increased vascular endothelial growth factor (VEGF) concentrations in obese mice, however, did not change the capillary/fiber ratio in ischemic legs. Systemic administration of ghrelin did not restore angiogenesis in hindlimb ischemia in control and diet-induced obese mice (Fig. 4, Ref. 35).