HDAC1-mediated regulation of KDM1A in pemphigus vulgaris: unlocking mechanisms on ERK pathway activation and cohesion loss.

Pemphigus vulgaris (PV) is an autoimmune skin disorder characterized by the loss of cell cohesion, with the histone deacetylase 1 (HDAC1) and lysine demethylase 1A (KDM1A) playing critical roles in its pathogenesis. This study aimed to elucidate the molecular mechanisms behind PV, focusing on the function of HDAC1 and KDM1A in disease onset and progression. Based on in vitro and in vivo PV models, we observed a significant increase in HDAC1 mRNA and protein levels in skin tissues of PV patients. Inhibition of HDAC1 ameliorated cell damage and reduced the loss of cell cohesion in human epidermal keratinocytes (HEKs) induced by PV-IgG. Our findings suggest that HDAC1 regulates KDM1A expression through deacetylation, with a notable deficiency in KDM1A expression in PV. Overexpression of KDM1A mitigated cell damage and cohesion loss. The extracellular signal-regulated kinase (ERK) pathway serves as a downstream executor of the HDAC1/KDM1A axis. Inhibiting HDAC1 and increasing KDM1A expression suppressed ERK phosphorylation, reducing PV-related apoptosis. These insights provide a new perspective on treating PV, highlighting the therapeutic potential of targeting HDAC1 expression. The regulatory mechanism of the HDAC1/KDM1A/ERK axis offers crucial clues for understanding PV pathogenesis and developing novel treatments.