摘要
本试验旨在探究番茄红素(LYC)对玉米赤霉烯酮(ZEN)、呕吐毒素(DON)和黄曲霉毒素B1(AFB1)联合暴露小鼠回肠损伤的保护作用及机制.选用80只6周龄无特异病原体(SPF)的ICR雄性小鼠[体重为(31.01±0.29)g],随机分为4组(每组20只),分别为:对照组、LYC组、霉菌毒素组和LYC+霉菌毒素组.将小鼠适应性饲养10 d后,连续灌胃10 mg/kg LYC或等量其溶剂14 d,随后腹腔注射10 mg/kg ZEN+1 mg/kg DON+0.5 mg/kg AFB1或等量溶剂.在处理结束时,小鼠禁食24 h后称重并处死,立即收集回肠样本待测.结果表明:1)与对照组相比,霉菌毒素组小鼠回肠隐窝深度极显著提高(P＜0.01),回肠绒毛高度/隐窝深度值显著降低(P＜0.05);与霉菌毒素组相比,LYC+霉菌毒素组回肠绒毛高度有提高趋势(P＞0.05),回肠隐窝深度有降低趋势(P＞0.05).2)与对照组相比,霉菌毒素组小鼠回肠封闭蛋白-1(claudin-1)、闭锁小带蛋白-1(ZO-1)和闭合蛋白(occludin)的分布减少;与霉菌毒素组相比,LYC+霉菌毒素组回肠claudin-1、ZO-1和occludin的分布增加.3)与对照组相比,霉菌毒素组小鼠回肠上皮细胞紧密连接模糊化,线粒体膜溶解,嵴断裂,且线粒体肿胀、空泡化严重;与霉菌毒素组相比,LYC+霉菌毒素组回肠上皮细胞紧密连接完整清晰,线粒体出现轻微的肿胀、空泡化.4)与对照组相比,霉菌毒素组小鼠回肠受体相互作用蛋白3(RIP3)和混合系列蛋白激酶结构域样蛋白(MLKL)蛋白表达量显著或极显著提高(P＜0.05或P＜0.01);与霉菌毒素组相比,LYC+霉菌毒素组回肠RIP3蛋白表达量显著降低(P＜0.05).5)与对照组相比,霉菌毒素组小鼠回肠受体相互作用蛋白1(RIP1)、RIP3和MLKL的mRNA表达量极显著提高(P＜0.01);与霉菌毒素组相比,LYC+霉菌毒素组回肠RIP1和RIP3的mRNA表达量极显著降低(P＜0.01).综上所述,LYC可通过维持肠道黏膜屏障及线粒体结构的完整性,抑制回肠程序性坏死信号通路,以减轻ZEN、DON和AFB1联合暴露引起的小鼠回肠损伤.
Abstract
The aim of this study was to investigate the protective effects of lycopene(LYC)on ileum injury of mice exposed to zearalenone(ZEN),deoxynivalenol(DON)and aflatoxin B1(AFB1)and its mechanism.A total of 80 specific pathogen free(SPF)male ICR mice of 6-week-old with body weight of(31.01±0.29)g were randomly divided into 4 groups(20 mice per group),which were control group,LYC group,mycotoxin group and LYC+mycotoxin group,respectively.After 10 days of adaptive feeding,the mice were given con-tinuous intragastric administration of 10 mg/kg LYC or its equivalent solvent for 14 days,followed by intraper-itoneal injection of 10 mg/kg ZEN+1 mg/kg DON+0.5 mg/kg AFB,or its equivalent solvent.At the end of the treatment,the mice were fasted for 24 h,then weighed and killed,and the ileum samples were collected immediately for testing.The results showed as follows:1)compared with the control group,the crypt depth of ileum of mice in mycotoxin group was extremely significantly increased(P＜0.01),and the villus height to crypt depth ratio of ileum was significantly decreased(P＜0.05);compared with mycotoxin group,the villus height of ileum in LYC+mycotoxin group had a tendency to increase(P＞0.05),and the crypt depth of ileum had a tendency to decrease(P＞0.05).2)Compared with the control group,the distribution of claudin-1,zonula occludens-1(ZO-1)and occludin in ileum of mice in mycotoxin group was decreased;compared with mycotoxin group,the distribution of claudin-1,ZO-1 and occludin in ileum in LYC+mycotoxin group was in-creased.3)Compared with the control group,the tight junctions in ileal epithelial cells of mice in mycotoxin group were blurred,the mitochondrial membrane was dissolved,the cristae were broken,and the mitochondria were swollen and vacuolated seriously;compared with mycotoxin group,the tight junctions in ileal epithelial cells in LYC+mycotoxin group were intact and clear,and the mitochondria showed slight swelling and vacuola-tion.4)Compared with the control group,the protein expression levels of receptor interaction protein 3(RIP3)and mixed series protein kinase domain-like protein(MLKL)in ileum of mice in mycotoxin group were significantly or extremely significantly increased(P＜0.05 or P＜0.01);compared with mycotoxin group,the RIP3 protein expression level in ileum in LYC+mycotoxin group was significantly decreased(P＜0.05).5)Compared with the control group,the mRNA expression levels of receptor interacting protein 1(RIP1),RIP3 and MLKL in ileum in mycotoxin group were extremely significantly increased(P＜0.01);compared with my-cotoxin group,the mRNA expression levels of RIP1 and RIP3 in ileum in LYC+mycotoxin group were ex-tremely significantly decreased(P＜0.01).In conclusion,LYC can maintain the integrity of intestinal mucosal barrier and mitochondrial structure,and inhibit the programmed necrosis signaling pathway in ileum,so as to alleviate the ileum injury of mice caused by ZEN,DON and AFB,combined exposure.[Chinese Journal of Animal Nutrition,2024,36(5):3306-3316]
基金项目
浙江省领军型创新创业团队项目(2020R01015)
国家自然科学基金青年基金(32002346)
万方数据