4-萜品醇对脂多糖诱导的免疫应激断奶仔猪肝脏发育、抗氧化能力和免疫功能的调节作用

Regulatory Effects of Terpinen-4-ol on Liver Development, Antioxidant Capacity and Immune Function of Weaned Piglets under Immune Stress Induced by Lipopolysaccharide

本试验旨在研究4-萜品醇(TER)对脂多糖(LPS)诱导的免疫应激断奶仔猪肝脏发育、抗氧化能力和免疫功能的调节作用。选取体重相近的28日龄仔猪40头(21日龄断奶),随机分为5组,每组8头仔猪。对照组(CON)和脂多糖组(LPS)饲喂基础饲粮,低、中和高剂量4-萜品醇组分别在基础饲粮中添加30(PLT组)、60(PMT组)和90 mg/kg(PHT组)的4-萜品醇。预试期3 d,正试期21 d。试验结束时,LPS组和各4-萜品醇组断奶仔猪腹腔注射100μg/kg BW的LPS,对照组腹腔注射等量的0.9%生理盐水。结果表明:1)与CON组相比,LPS组肝脏重和肝脏指数显著降低(P<0.05)。与LPS组相比,PHT组肝脏重显著提高(P<0.05)。2)CON组肝脏细胞细胞质完好,未发现明显炎症和坏死的现象;LPS组肝脏组织出现严重损伤,包括肝脏细胞坏死、细胞肿胀、细胞膜结构破坏以及核的收缩。与CON组相比,LPS组肝脏细胞面积和粒径均显著降低(P<0.05)。与LPS组相比,PLT、PMT和PHT组肝脏细胞面积和粒径均显著提高(P<0.05)。3)与CON组相比,LPS组肝脏过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)活性显著降低(P<0.05)。与LPS组相比,PLT、PMT和PHT组肝脏GSH-Px活性显著提高(P<0.05)。4)与CON组相比,LPS组肝脏白细胞介素-1β(IL)含量显著升高(P<0.05)。与LPS组相比,PMT和PHT组肝脏IL-1β含量显著降低(P<0.05),PHT组肝脏白细胞介素-6(IL-6)和白细胞介素-8(IL-8)含量显著降低(P<0.05)。由此可见,LPS刺激可导致断奶仔猪肝脏损伤,肝脏抗氧化和免疫功能受损;饲粮中添加4-萜品醇可通过提高断奶仔猪肝脏抗氧化酶活性、减少促炎因子含量、增加抗炎因子含量,增强抗氧化能力和免疫功能,缓解肝脏炎症损伤。

The aim of this study was to investigate the regulatory effects of terpinen-4-ol(TER)on liver development,antioxidant capacity and immune function of weaned piglets under immune stress induced by LPS.Forty 28-day-old weaned piglets(weaned at 21 days of age)with similar body weight were selected and randomly divided into five groups with eight piglets per group.Piglets in the control group(CON group)and lipopolysaccharide group(LPS group)were fed a basal diet,and others in low,medium and high-dose terpinen-4-ol groups were fed the basal diet supplemented with 30(PLT group),60(PMT group)and 90 mg/kg(PHT group)terpinen-4-ol,respectively.The pre-experimental period lasted for 3 days,and the experimental period lasted for 21 days.At the end of the experiment,the weaned piglets in LPS group and terpinen-4-ol groups were intraperitoneally injected with 100μg/kg BW of LPS,while others in the control group were intraperitoneally injected with equivalent dose of 0.9%saline.The results showed as follows:1)compared with CON group,the liver weight and liver index of LPS group were significantly decreased(P<0.05).Compared with LPS group,the liver weight of PHT group was significantly increased(P<0.05).2)The cytoplasm of liver cells of CON group was intact,no obvious inflammation and necrosis were found;the liver tissue of LPS group was seriously damaged,including liver cell necrosis,cell swelling,cell membrane structure destruction and nuclear contraction.Compared with CON group,the area and particle size of liver cells of LPS group were significantly decreased(P<0.05).Compared with LPS group,the area and particle size of liver cells of PLT,PMT and PHT groups were significantly increased(P<0.05).3)Compared with CON group,the activities of catalase(CAT)and glutathione peroxidase(GSH-Px)in liver of LPS group were significantly decreased(P<0.05).Compared with LPS group,the liver GSH-Px activity of PLT,PMT and PHT groups was significantly increased(P<0.05).4)Compared with CON group,the liver interleukin-1β(IL-1β)content of LPS group was significantly increased(P<0.05).Compared with LPS group,the liver IL-1βcontent of PMT and PHT groups was significantly decreased(P<0.05),and the contents of interleukin-6(IL-6)and interleukin-8(IL-8)in liver of PHT group were significantly decreased(P<0.05).In conclusion,the LPS stimulation can lead to liver damage,liver antioxidant and immune function impairment.Dietary terpinen-4-ol can enhance antioxidant capacity and immune function and alleviate liver inflammatory damage of weaned piglets by increasing liver antioxidant oxidase activity,reducing pro-inflammatory factor content and increasing anti-inflammatory factor content.