The PPAR-α agonist oleoyethanolamide (OEA) ameliorates valproic acid-induced steatohepatitis in rats via suppressing Wnt3a/β-catenin and activating PGC-1α: Involvement of network pharmacology and molecular docking

Abstract

Liver damage is one of the most severe side effects of valproic acid (VPA) therapy. Research indicates that PPAR-α prevents Wnt3a/β-catenin-induced PGC-1α dysregulation, which is linked to liver injury. Although PPAR-α activation has hepatoprotective effects, its role in preventing VPA-induced liver injury remains unclear. Our research used network analysis, molecular docking, and in-vivo validation to predict and assess targets and pathways associated with the hepatoprotective effects of oleoylethanolamide (OEA), a PPAR-α agonist, on VPA-induced steatohepatitis. For in-vivo experiments, 24 rats were assigned to V, OEA, VPA, and OEA + VPA. Liver functions, TGs, cholesterol, and LDL were tested. Hepatic levels of PPAR-α, ACO, TNF-α, IL-1β, HO-1, MDA, and TAC, along with Wnt3a/β-catenin, PGC-1α, and Nrf2 expression were assessed. Further, NF-κB, Bax, Bcl-2, and caspase-3 expression were detected immunohistochemically. Network pharmacology identified 258 targets for OEA-steatohepatitis connection, including NFKB1, PPARA, and NFE2L2, in addition to TNF, non-alcoholic fatty liver, NF-κB, PPAR, and WNT signaling, as contributing to steatohepatitis pathogenesis. The docking revealed a strong affinity between OEA and Wnt3a, β-catenin, and PGC-1α. Therefore, we postulated that the hepatoprotective effect of OEA may be due to Wnt3a/β-catenin-mediated inactivation of PGC1-α pathway. In vivo, OEA inhibited Wnt3a/β-catenin and increased PGC1-α by activating PPAR-α. Hence, PGC1-α reduced fat cell β-oxidation and NF-κB-mediated inflammation. OEA lessened MDA and raised TAC to mitigate oxidative damage. OEA additionally reduced apoptosis by lowering Bax/Bcl-2 ratio and caspase-3. In summary, PPAR-α involvement in the protective effects of OEA against VPA-induced steatohepatitis can be confirmed by suppressing Wnt3a/β-catenin and activating PGC-1α signaling.