Ameliorative effect of phenolic compound-pterostilbene on corticosterone-induced hepatic lipid metabolic disorder in broilers

The aim of this study was to investigate the ameliorative effects of pterostilbene (PTE), a polyphenolic compound, on stress-induced lipid metabolic disorders in the liver of broiler chickens. Six hundred healthy, 1-day-old Arbor Acres with similar weight were randomly assigned to five groups, each consisting of eight replicates with 15 broilers per replicate. The groups included: a control group (fed a basal diet), and four groups treated with corticosterone (CORT) at varying dietary levels of PTE supplementation: CORT (0 mg/kg PTE), CORT-PT200 (200 mg/kg PTE), CORT-PT400 (400 mg/kg PTE), and CORT-PT600 (600 mg/kg PTE). The results indicated that PTE administration to corticosterone (CORT)-injected broilers significantly improved weight gain, reduced liver index, and lowered the elevation of serum aspartate aminotransferase, gamma-glutamyl transferase, glucose, total cholesterol, triglycerides, and lipoprotein cholesterol concentrations induced by CORT injection (P<.05), but had no significant effect on serum CORT concentration (P>.05). PTE also significantly reduced the increased rate of abdominal fat deposition induced by CORT, decreased the average size of adipocytes, and downregulated the expression of the FAS gene (P<.05). It reversed the increase in liver total cholesterol, triglycerides, lipoprotein cholesterol, and non-esterified fatty acids content induced by CORT (P<.05). PTE had no significant effect on the expression of the glucocorticoid receptor (P>.05), but significantly upregulated the protein expression of Sirt1 and p-AMPK (P<.05), promoted the expression of lipid autophagy genes MAP1LC3B and lipolytic genes LPL, but inhibited the expression of fatty acid synthesis genes SREBP-1c, ACC, and SCD (P<.05). The addition of PTE to the diet alleviated CORT-induced oxidative stress and inflammation by enhancing T-SOD and GSH-Px activities, reducing MDA content, inhibiting p-NF-κB p65 and NLRP3 expression and the release of TNF-α and IL-1β in the serum, and increasing IL-4 content (P<.05). Overall, dietary PTE effectively regulates lipid metabolism and antioxidant status, offering a potential strategy to mitigate stress-induced metabolic disruptions in broilers.