(P15-004-25) Poria cocos Polysaccharides Alleviated Porcine Epidemic Diarrhea Virus-Induced Intestinal Injury by Modulating Lipid Metabolism in Piglets

Objectives: Poria cocos polysaccharides (PCP) exhibited immunomodulatory and intestinal repair properties. As vaccine adjuvant, PCP enhanced immune responses of both human and animals. Porcine epidemic diarrhea virus (PEDV) caused severe diarrhea and high mortality in piglets, disrupting intestinal integrity and posing challenges for control due to genetic variability. This study investigated the potential of PCP to mitigate PEDV-induced intestinal damage of piglets and underlying mechanisms.

Methods: Eighteen 7-day-old piglets (2.6 ± 0.3 kg) were randomly assigned to 3 groups: control, PEDV, and PCP + PEDV. All piglets were fed milk replacer ad libitum during the 11-day trial. After a 3-day adaptation period, the PCP + PEDV group received PCP (10 mg/kg BW) daily from days 4–10. On day 8, PEDV (10⁴. ⁵ TCID₅₀) was administered to the PEDV and PCP + PEDV groups, while the control group received PBS. On day 11, after fasting, piglets were weighed, given D-xylose, and sampled for blood and intestinal tissues for analysis.

Results: The PCP administration effectively alleviated diarrhea, reduced PEDV replication in the small intestine and colon of piglets, and significantly improved intestinal mucosal morphology by increasing villus height in both the jejunum and ileum, as well as enhancing the villus height to crypt depth ratio in the ileum. Improved intestinal function was indicated by elevated D-xylose levels and decreased DAO levels in plasma. Transcriptomic and proteomic analyses highlighted the role of lipid metabolism in PCP's regulation of PEDV infection, while metabolomic analysis revealed that PCP primarily modulated the levels of plasmanylphosphoethanolamine, lysophosphatidylcholine, and carnitine. Furthermore, PCP reversed the expression of FABP2, FATP4, APOB, APOC3, FASN, ACSL3, LPL and ACOT12, all of which are involved in fatty acid uptake, intracellular lipid transport, and fatty acid synthesis in enterocytes.

Conclusions: The PCP could effectively resist PEDV infection and mitigate intestinal injury by modulating lipid metabolism in PEDV-infected piglets. The enhancement of anti-PEDV defenses and improvement of overall intestinal health by PCP in piglets indicated its potential in human nutrition.

Funding Sources: This work was supported by the National Natural Science Foundation of China (U22A20514, 32172763).