Polygonatum sibiricum Polysaccharides Alleviate LPS-Induced Liver Injury in Chicks by Suppressing Inflammation and Oxidative Stress Through the PPAR Signaling Pathway.

Polygonatum sibiricum polysaccharides (PSPs), plant-derived polysaccharides widely used in the pharmaceutical field, exhibit various biological activities, including anti-inflammatory and antioxidant effects. However, research on their application in chicks remains limited. Therefore, the aim of this study is to investigate the protective mechanism of PSP against liver injury in chicks using an LPS-induced inflammatory model. A total of 200 one-day-old Hy-Line Brown laying chicks were randomly assigned to five groups (40 chicks each): a control group (CON) fed a basal diet, an LPS group, and three PSP groups receiving low (250 mg/L), medium (500 mg/L), and high (1000 mg/L) doses of PSP (PSP250_LPS, PSP500_LPS, and PSP1000_LPS, respectively). The experiment lasted 21 days. During this period, the LPS and PSP groups were intraperitoneally injected with 1500 μg/kg LPS on days 14, 16, 18, and 20, while the CON group received normal saline. On day 21, organs were collected for analysis. The results indicated that PSP treatment significantly reduced the liver and kidney indices that were elevated by LPS (p < 0.05) without affecting the indices of the spleen, thymus, or bursa of Fabricius (p > 0.05). Histological analysis revealed that PSP alleviated LPS-induced ballooning degeneration and cell swelling in hepatocytes. Furthermore, PSP treatment decreased the levels of ALT and AST and significantly mitigated increases in the pro-inflammatory cytokines IL-1β, IL-6, and TNF-α while enhancing the level of the anti-inflammatory cytokine IL-10 (p < 0.05). Transcriptome sequencing of liver samples revealed that LPS significantly altered the expression of 10 genes in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which were regulated by PSP intervention. qPCR validation supported these findings. Furthermore, biochemical analyses of liver tissue showed that PSP alleviated oxidative stress by affecting levels of SOD, MDA, NADPH, ROS, and H(2)O(2). In conclusion, PSP may alleviate LPS-induced liver injury in chicks by modulating the PPAR signaling pathway. These findings provide valuable insights for promoting healthy chick rearing and ensuring the safe supply of poultry products.