• • MSCs significantly improved IMQ-induced psoriasis skin lesions in mice, reducing inflammatory cytokines (IL-1β, IL-6, IL-8, TNF-α) and chemokines (MCP-1, CCL7, CCL20, CCL27) in skin lesions and M5-induced HaCaT cells, with statistical significance (P<0.05 to P<0.001).
• • MSCs restored skin barrier by upregulating claudin-1 expression in vivo, and normalized keratinocyte differentiation markers (increased KRT1, decreased KRT6) both in vivo and in vitro, indicating functional recovery of epidermal differentiation.
• • Amino acid metabolomics showed MSCs improved serine metabolism in mouse skin, upregulating key enzyme PSPH; knockdown of PSPH reversed MSCs' therapeutic effects in vitro, confirming PSPH as a critical mediator.
• • MSCs activated PINK1-Parkin mitophagy pathway, with elevated PINK1, Parkin, p-Parkin, Beclin-1, and LC3B-II/I ratio, and reduced P62 (n=3, P<0.05 to P<0.001), leading to suppression of NLRP3 inflammasome and keratinocyte hyperproliferation.