Parishin Protects Against Sepsis-Induced Intestinal Injury by Modulating the ACSL4/p-Smad3/PGC-1α Pathway: An Integrated Approach of Bioinformatics and Experimental Validation

Abstract

Background: Sepsis is a major clinical challenge, with in-hospital mortality of 25%-40% in intensive care unit patients. The gastrointestinal tract is recognized as both the “initiating organ” of multiple organ dysfunction syndrome and the “central organ” in orchestrating the host stress response during critical illness. ACSL4, a regulator of lipid metabolism and ferroptosis, is a potential target for sepsis-induced intestinal injury, but its inhibitor parishin has not been evaluated in this context. Methods: Key genes implicated in sepsis pathogenesis were identified through bioinformatic analysis of publicly available datasets from the GEO. Network pharmacology approaches were used to screen for small-molecule compounds with high binding affinity to the identified hub genes. Molecular docking, followed by in vivo and in vitro validation, was employed to evaluate the therapeutic efficacy and mechanistic impact of the top candidate compound in a murine sepsis model. Results: Weighted Gene Co-expression Network Analysis identified five genes most significantly associated with sepsis diagnosis. Protein-protein interaction network analysis revealed 157 hub genes, among which ACSL4 was the sole gene shared across diagnostic and functional modules. Molecular docking analysis indicated that Parishin exhibited the strongest binding affinity to ACSL4 (docking score: −17.701). In septic animal models, ACSL4 expression was markedly upregulated in both plasma monocytes and intestinal tissues (P < 0.05), accompanied by increased levels of inflammatory cytokines, lipid peroxidation (LPO), MDA, and Fe2+ (P < 0.05). Expression of ferroptosis-associated proteins was also evidently elevated (P < 0.05). Treatment with Parishin notably attenuated these pathological changes, reduced ferroptosis-related markers, and improved 72-hour survival rates in septic mice (P < 0.05). Conclusion: Parishin ameliorates sepsis-induced intestinal injury by downregulating ACSL4 expression, thereby inhibiting Smad3 phosphorylation and suppressing ferroptosis. These findings suggest that ACSL4 is a promising therapeutic target for mitigating intestinal damage in sepsis.