LSD1-S112A exacerbates the pathogenesis of CSE/LPS-induced chronic obstructive pulmonary disease in mice.

Lysine-specific demethylase 1 (LSD1) is an epigenetic regulator that modulates the chromatin status, contributing to gene activation or repression. The post-translational modification of LSD1 is critical for the regulation of many of its biological processes. Phosphorylation of serine 112 of LSD1 by protein kinase C alpha (PKCα) is crucial for regulating inflammation, but its physiological significance is not fully understood. This study aimed to investigate the role of Lsd1-S112A, a phosphorylation defective mutant, in the cigarette smoke extract/LPS-induced chronic obstructive pulmonary disease (COPD) model using Lsd1SA/SA mice and to explore the potential mechanism underpinning the development of COPD. We found that Lsd1SA/SA mice exhibited increased susceptibility to CSE/LPS-induced COPD, including high inflammatory cell influx into the bronchoalveolar lavage fluid and airspace enlargement. Additionally, the high gene expression associated with the inflammatory response and oxidative stress was observed in cells and mice containing Lsd1-S112A. Similar results were obtained from the mouse embryonic fibroblasts exposed to a PKCα inhibitor, Go6976. Thus, the lack of LSD1 phosphorylation exacerbates CSE/LPS-induced COPD by elevating inflammation and oxidative stress. [BMB Reports 2021; 54(10): 522-527].

Inhibition of LSD1 phosphorylation alleviates colitis symptoms induced by dextran sulfate sodium.

Inflammatory Bowel Disease is caused by an acute or chronic dysfunction of the mucosal inflammatory system in the intestinal tract. In line with the results of our previous study, wherein we found that the PKCα-LSD1-NF-κB signaling plays a critical role in the prolonged activation of the inflammatory response, we aimed to investigate the effect of signaling on colitis in the present study. Lsd1 S112A knock-in (Lsd1SA/SA) mice, harboring a deficiency in phosphorylation by PKCα, exhibited less severe colitis symptoms and a relatively intact colonic epithelial lining in dextran sulfate sodium (DSS)- induced colitis models. Additionally, a reduction in pro-inflammatory gene expression and immune cell recruitment into damaged colon tissues in Lsd1SA/SA mice was observed upon DSS administration. Furthermore, LSD1 inhibition alleviated colitis symptoms and reduced colonic inflammatory responses. Both LSD1 phosphorylation and its activity jointly play a role in the progression of DSS-induced colitis. Therefore, the inhibition of LSD1 activity could potentially protect against the colonic inflammatory response. [BMB Reports 2020; 53(7): 385-390].