Mao Xinru, Zhang Ping, Du Heng, Ge Lei, Liu Shuiping, Huang Kehe, Chen Xingxiang
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China; Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China.
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China.
Toxicol Lett. 2023 Jan 1;372:25-35. doi: 10.1016/j.toxlet.2022.10.007. Epub 2022 Oct 26.
Currently, due to the actual contamination levels of multiple mycotoxins, the limits for a single mycotoxin may be no longer applicable. Deoxynivalenol (DON) and Fumonisin B (FB) had high positive rate in grain and feed worldwide. The intestine is the first target of mycotoxins. NLRP3 plays a crucial role in the gut's defense against external stimuli, which contributes vitally to pyroptosis activation. However, whether pyroptosis is engaged in the regulation of intestinal toxicity induced by DON and FB remains unclear. In this study, we explored the combined toxicity of DON and FB on the intestine and its underlying mechanisms in vivo and in vitro. Our data demonstrated gavage with DON and FB led to intestinal damage and promoted the secretion of pro-inflammatory cytokines (IL-1β, IL-18, IL-6) in mice, especially in the group exposed to both mycotoxins. Meanwhile, the expressions of pyroptosis related genes (NLRP3, ASC, caspase-1, GSDMD) were significantly increased after mycotoxins exposure. Same as in vivo, DON and FB promoted pyroptosis and cellular inflammatory response in IPEC-J2 cells, especially in the group exposed to both mycotoxins. In addition, the pretreatment with MCC950 and VX765, inhibitors for NLRP3 and caspase-1, abolished the expression of GSDMD and the release of pro-inflammatory factors (IL-1β, IL-18) induced by DON and FB exposure in IPEC-J2 cells. Our data demonstrated that the combination of DON and FB exhibited a synergistic or additive effect in facilitating intestinal inflammation via pyroptosis. Our finding may contribute to improve mycotoxin limit standards in feed.
目前，由于多种霉菌毒素的实际污染水平，单一霉菌毒素的限量可能不再适用。脱氧雪腐镰刀菌烯醇（DON）和伏马菌素B（FB）在全球范围内的谷物和饲料中阳性率较高。肠道是霉菌毒素的首要作用靶点。NLRP3在肠道抵御外部刺激的防御过程中发挥关键作用，对细胞焦亡的激活至关重要。然而，细胞焦亡是否参与DON和FB诱导的肠道毒性调节仍不清楚。在本研究中，我们在体内和体外探究了DON和FB对肠道的联合毒性及其潜在机制。我们的数据表明，给小鼠灌胃DON和FB会导致肠道损伤，并促进促炎细胞因子（IL-1β、IL-18、IL-6）的分泌，尤其是在同时暴露于两种霉菌毒素的组中。同时，暴露于霉菌毒素后，细胞焦亡相关基因（NLRP3、ASC、caspase-1、GSDMD）的表达显著增加。与体内情况相同，DON和FB促进了IPEC-J2细胞中的细胞焦亡和细胞炎症反应，尤其是在同时暴露于两种霉菌毒素的组中。此外，用NLRP3抑制剂MCC950和caspase-1抑制剂VX765预处理，消除了DON和FB暴露诱导的IPEC-J2细胞中GSDMD的表达以及促炎因子（IL-1β、IL-18）的释放。我们的数据表明，DON和FB的组合在通过细胞焦亡促进肠道炎症方面表现出协同或相加作用。我们的发现可能有助于改进饲料中的霉菌毒素限量标准。
