Vibrio parahaemolyticus infection induces time-dependent ferroptosis in the liver of silver pomfret (Pampus argenteus)

The silver pomfret (Pampus argenteus), an economically important species in China, which is susceptible to Vibrio infection during farming. Vibrio parahaemolyticus is a gram-negative bacterium that is known to cause significant infections in marine fish. However, the molecular mechanisms underlying the silver pomfret's response to V. parahaemolyticus infection remain unclear. In this study, healthy silver pomfrets were included in the control group. Artificial infection of silver pomfrets was performed via intraperitoneal injection, and the hepatic responses were analyzed at multiple post-infection time points, including 3, 12, 24 and 48 h post-infection (hpi). A total of 50 fish (10 per group) were used, including controls and infected groups at multiple time points. Histopathological changes were observed in infected tissues. Furthermore, Integrated analysis of differentially expressed genes (DEGs) and Weighted Gene Coexpression Network Analysis (WGCNA) identified a temporally regulated defense cascade in silver pomfrets following V. parahaemolyticus infection. This cascade is characterized by sequential phase transitions: early cell death at 3 hpi, an oxidative stress response at 12 hpi, antibody presentation at 24 hpi, and metabolic regulation at 48 hpi. Interestingly, gene set enrichment analysis (GSEA) revealed persistent activation of the ferroptosis signaling pathway. Additionally, WGCNA identified several hub genes, including usp5, fbxw7, maff and ldha, which have been reported to be associated with the occurrence of ferroptosis. Therefore, ferroptosis was selected as the focus of our subsequent research. Measurements of ferroptosis-related markers (genes, Fe²⁺, oxidative stress, and key proteins) revealed that the ferroptotic response in silver pomfret exhibited a time-dependent and progressively intensified pattern during V. parahaemolyticus infection. These findings provide valuable insights into the acute immune response of silver pomfrets challenged with V. parahaemolyticus and establish a foundation for identifying molecular targets and developing therapeutic interventions against Vibrio infections in economically important marine fish farming.