Mechanisms underlying the pathogenesis of hyper-contractility of bronchial smooth muscle in allergic asthma.

Mechanisms underlying the pathogenesis of hyper-contractility of bronchial smooth muscle in allergic asthma. J Smooth Muscle Res. 2017;53(0):37-47 Authors: Sakai H, Suto W, Kai Y, Chiba Y Abstract Airway hyperresponsiveness (AHR) and inflammation are key pathophysiological features of asthma. Enhanced contraction of bronchial smooth muscle (BSM) is one of the causes of the AHR. It is thus important for development of asthma therapy to understand the change in the contractile signaling of airway smooth muscle cells associated with the AHR. In addition to the Ca(2+)-mediated phosphorylation of myosin light chain (MLC), contractile agonists also enhance MLC phosphorylation level, Ca(2+)-independently, by inactivating MLC phosphatase (MLCP), called Ca(2+) sensitization of contraction, in smooth muscle cells including airways. To date, involvements of RhoA/ROCKs and PKC/Ppp1r14a (also called as CPI-17) pathways in the Ca(2+) sensitization have been identified. Our previous studies revealed that the agonist-induced Ca(2+) sensitization of contraction is markedly augmented in BSMs of animal models of allergen-induced AHR. In BSMs of these animal models, the expression of RhoA and CPI-17 proteins were significantly increased, indicating that both the Ca(2+) sensitizing pathways are augmented. Interestingly, incubation of BSM cells with asthma-associated cytokines, such as interleukin-13 (IL-13), IL-17, and tumor necrosis factor-α (TNF-α), ...
Source: Journal of Smooth Muscle Research - Category: Research Tags: J Smooth Muscle Res Source Type: research