Interleukin-10 limits increased blood pressure and vascular RhoA/Rho-kinase signaling in angiotensin II-infused mice.

Aims: Interleukin-10 (IL-10) is a multi-functional cytokine with potent anti-inflammatory properties. We hypothesized that IL-10 limits increased RhoA/Rho-kinase signaling and vascular reactivity in arteries from angiotensin II (Ang II) hypertensive mice.

Main Methods: Wild type (WT) and IL-10 knockout ((-/-)) mice were infused with Ang II (90ng/min) for 14days. Additionally, WT mice were infused with Ang II and simultaneously infused with exogenous IL-10 (0.5ηg/min, 14days). Aortic rings were mounted in a myograph and concentration-response curve to phenylephrine (PE) were evaluated.

Key Findings: After Ang II infusion, blood pressure responses, but not maximal contraction to PE, was greater in IL-10(-/-) mice, compared to WT. Rho-kinase inhibition (Y-27632; 10μM) resulted in a more evident reduction of PE-induced contraction in WT hypertensive mice, when compared to IL-10(-/-) hypertensive mice. IL-10 exogenous infusion prevented the blood pressure increase in Ang II-infused WT mice. The augmented PE-contraction observed in aorta from WT mice infused with Ang II was also prevented by exogenous infusion of IL-10. Additionally, Rho-kinase inhibition (Y-27632; 10μM) abolished the differences in the contractile response to PE between these groups.

Significance: These results demonstrate that IL-10 counteracts both the pressoric activity of Ang II as well as vascular dysfunction associated with hypertension, partially, modulating the RhoA-Rho kinase pathway. Strategies to enhance IL-10 levels during hypertension may enhance the benefits provided by regular treatments.