Roles of interleukin 17 in angiotensin II type 1 receptor-mediated insulin resistance.

Department of Molecular Cardiovascular Biology and Pharmacology, Ehime University, Graduate School of Medicine, Shitsukawa, Tohon, Ehime 791-0295, Japan.
Hypertension (Impact Factor: 6.87). 12/2011; 59(2):493-9. DOI: 10.1161/HYPERTENSIONAHA.111.183178
Source: PubMed

ABSTRACT Interleukin 17 (IL-17) is known to contribute to the pathogenesis of hypertension, atherosclerosis, and adipocyte differentiation; however, the roles of IL-17 in glucose metabolism remain to be elucidated. Angiotensin II type 1 receptor blockers improve insulin resistance at least in part because of the amelioration of inflammation. Therefore, we examined the possible roles of IL-17 in the pathogenesis of insulin resistance in type 2 diabetes mellitus using a mouse model, KK-Ay, and angiotensin II type 1 receptor-mediated insulin resistance. KK-Ay mice were administered control-IgG(2A) or anti-IL-17 antibody 5 times at a dose of 100 μg every second day by IP injection. KK-Ay mice were administered telmisartan for 2 weeks. C57BL/6J mice treated with angiotensin II infusion for 2 weeks were administered telmisartan or hydralazine. Insulin resistance was evaluated by oral glucose tolerance test, insulin tolerance test, and uptake of 2-[(3)H]deoxy-d-glucose in peripheral tissues. Serum IL-17 concentration in KK-Ay mice was significantly higher than that in C57BL/6J mice. Treatment of KK-Ay mice with anti-IL-17 antibody significantly increased 2-[(3)H]deoxy-d-glucose uptake in skeletal muscle but not in white adipose tissue and attenuated the increase in blood glucose level after a glucose load. Blockade of IL-17 enhanced the expression of adipocyte differentiation markers and adiponectin. Treatment with telmisartan decreased serum IL-17 concentration in KK-Ay and ameliorated angiotensin II-induced insulin resistance with a decrease in serum IL-17 level in C57BL/6J. In conclusion, IL-17 could play an important role in the pathogenesis of angiotensin II type 1 receptor-induced insulin resistance.

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