N-乙酰半胱氨酸对脂多糖刺激仔猪空肠黏膜抗氧化能力的影响

Effects of Dietary N-acetylcysteine on the Antioxidant Capacity of Jejunal Mucosa of Piglets Challenged with Lipopolysaccharide

本试验旨在研究N-乙酰半胱氨酸(NAC)对脂多糖(LPS)慢性刺激仔猪空肠黏膜抗氧化能力的影响。选用18头健康仔猪[平均体重为(11.58±0.26)kg],随机分为3个组(对照组、LPS组、NAC组),每组6个重复,每个重复1头猪。对照组和LPS组饲喂基础饲粮,NAC组饲喂基础饲粮+0.05%NAC。在试验第10天、第13天和第20天清晨,LPS组和NAC组仔猪腹膜注射100μg/kg BW的LPS,对照组注射相应剂量的灭菌生理盐水。第21天屠宰,取小肠黏膜样品,待测。结果表明:1)LPS刺激降低了仔猪空肠黏膜超氧化物歧化酶(SOD,P<0.01)和过氧化氢酶(CAT,P<0.01)活性,提高了一氧化氮合酶(NOS,P<0.05)和诱导型一氧化氮合酶(iNOS,P<0.01)活性;饲粮中添加0.05%的NAC提高了LPS刺激仔猪空肠黏膜CAT活性(P<0.01),降低了iNOS活性(P<0.01)。2)LPS刺激提高了仔猪空肠黏膜丙二醛(MDA,P<0.05)、过氧化氢(H2O2,P<0.05)、超氧阴离子(O-2,P<0.01)含量和氧化型谷胱甘肽/还原型谷胱甘肽(GSSG/GSH,P<0.01);饲粮中添加0.05%的NAC降低了LPS刺激仔猪空肠黏膜MDA(P<0.05)、H2O2(P<0.05)、O-2含量(P<0.01)和GSSG/GSH(P<0.01)。由此可知,饲粮中添加0.05%NAC能有效缓解LPS刺激对仔猪肠黏膜抗氧化能力的负影响。

The study was conducted to investigate the effects of N-acetylcystine（NAC） on the antioxidant capacity of jejunal mucosa of piglets chronically challenged with lipopolysaccharide（LPS）.Eighteen healthy piglets [average body weight,（11.58±0.26） kg] were randomly allocated into 3 groups（control group,LPS group and NAC group）.Each group included 6 replicates with one piglet per replicate.The control group and LPS group were fed the basal diet,and NAC group was fed the basal diet supplemented with 0.05% NAC.On d 10,13 and 20,piglets in the LPS and NAC groups were injected intraperitoneally with LPS at 100 μg/kg BW,whereas piglets in the control group were injected intraperitoneally with normal sterile saline at the same volume.On d 21,all pigs were sacrificed to obtain jejunal mucosa for analysis.The results showed as follows： 1） LPS challenge reduced the activities of superoxide dismutase（SOD,P0.01） and catalase（CAT,P0.01）,and increased the activities of nitric oxide synthase（NOS,P0.05） and inducible nitric oxide synthase（iNOS,P0.01） in jejunal mucosa of the piglets;the supplementation of 0.05% NAC in the diet increased CAT activity（P0.01）,and reduced iNOS activity（P0.01） in jejunal mucosa of the piglets challenged with LPS.2） LPS challenge increased the contents of malondialdehyde（MDA,P0.05）,hydrogen peroxide（H2O2,P0.05） and superoxide anion（O-2,P0.01）,and glutathione oxidized/glutathione（GSSG/GSH,P0.01） ratio in jejunal mucosa of the piglets;the supplementation of 0.05% NAC in the diet reduced the contents of MDA（P0.05）,H2O2（P0.05） and O-2（P0.01）,and GSSG/GSH ratio（P0.01） in jejunal mucosa of the piglets challenged with LPS.In conclusion,the supplementation of 0.05% NAC in the diet can effectively alleviate the oxidative stress in intestinal mucosa of the piglets induced by LPS challenge.