酿酒酵母NAU-LYH-SGS株对猪OTA中毒的干预作用及其机制研究

赭曲霉毒素A(OTA)是广泛存在于饲料中的一种具有很强毒性的霉菌毒素，有大量猪OTA中毒的报道。酿酒酵母NAU-LYH-SGS株由本研究室自主分离，能产GSH和硒蛋氨酸。初步研究表明，该菌株能降解OTA，减弱OTA的肠、肾和免疫毒性。本项目首先是通过仔猪试验，进一步确认该菌株防控猪OTA中毒的效果，并从肠内微生物群落多样性、OTA降解、肠道屏障功能、SIRT1通路和自噬等方面探讨机制。其次用该菌株与猪上皮细胞IPEC-J2共培养，应用电镜、流式细胞术、免疫印迹和RNA干扰等技术研究其减弱OTA肠毒性的效果与信号通路机制。最后以猪肾细胞和原代T淋巴细胞为模型，进一步应用GFP-LC3转染和激光共聚焦等技术研究酵母多糖、硒蛋氨酸或/和GSH减弱OTA的肾毒性和免疫毒性的自噬机制。目的是阐明该菌株防控猪OTA中毒的机制，为其广泛应用提供科学依据，项目无疑对猪OTA中毒的防控和人类健康有重要意义。

Ochratoxin A (OTA) is a world-wide potent mycotoxin that naturally occurs in food and feeds， and there are many reports of pig OTA poisoning. Saccharomyces cerevisiae NAU-LYH-SGS is isolated by our lab, and can produce GSH and selenomethionine. Preliminary study showed that Saccharomyces cerevisiae NAU-LYH-SGS can degrade OTA, and alleviate the OTA-induced enterotoxigenesis, nephrotoxicity and immunotoxicity. The contents of the project are as follows: ① verifying the protective effects of Saccharomyces cerevisiae NAU-LYH-SGS on OTA-induced toxicity and exploring the mechanism from intestinal microbial community diversity, OTA degradation, the intestinal barrier function, SIRT1 pathways and autophagy by using piglets as the model; ② investigating the alleviating effects of Saccharomyces cerevisiae NAU-LYH-SGS on OTA-induced enterotoxigenesis and their signaling pathway mechanism by using IPEC-J2 cells to co-culture with Saccharomyces cerevisiae NAU-LYH-SGS; ③ investigating the alleviating effects of zymosan, GSH or/and selenomethionine on OTA-induced nephrotoxicity and immunotoxicity and their autophagy mechanism by using the porcine kidney 15 cells and porcine primary T lymphocyte cells as the models. Someadvanced technologies such as transmission electron microscopy, flow cytometry, western blotting, GFP-LC3 transfection, confocal laser, and RNA interference will be used in the project. The objective is to clarify the mechanism of the protective effects of Saccharomyces cerevisiae NAU-LYH-SGS on OTA poisoning, and provide a scientific basis for Saccharomyces cerevisiae NAU-LYH-SGS widely use in livestock production, and for the control of OTA poisoning and human health.