Activation of α-7 Nicotinic Acetylcholine Receptor Attenuates Cardiac Inflammation Through NLRP3/Caspase-1/IL-18 Pathway

Abstract

Activation of α-7 nicotinic acetylcholine receptor (α7nAChR) receptor might induce cardiac inflammation, cardiac remodeling, and dysfunction. In this regard, this study aims to clarify the role and mechanism of α7nAChR in the process of cardiac inflammation and damage. Normal male C57BL/6J and NLRP3-knockout mice were used to evaluate the effect of PHA-543613, a selective agonist of α7nAChR, on cardiac inflammation and possible involvement of NLRP3/Caspase-1/IL-18 using western blotting and ELISA. Activation of α7nAChR using PHA-543613 (NE), at the doses of 0.5 mg/kg and 1 mg/kg, induced cardiac inflammation. In addition, both in vivo and in vitro studies showed higher expression of NLRP3 and higher activation of Caspase-1 and IL-18 after treating animals with NE. On the other hand, we did not observe any significant changes in inflammatory cytokines and cardiac inflammation after administration of NE in NLRP3-knockout mice. It could be concluded that blocking the NLRP3/Caspase-1/IL-18 pathway can simultaneously inhibit the inflammatory response mediated by α7nAChR and it would a novel target for inhibiting cardiac inflammation and remodeling.

Keywords: Cardiac inflammation; Cardiac remodeling; Caspase-1; IL-18; NLRP3; α7nAChR.