大肠埃希菌LPS感染对乌鸡脂肪代谢及相关调控基因表达的影响  

Effects of the inflammation mediated by Escherichia coli LPS on the lipid metabolism and the expression of genes of black-bone chicken

作　　者：齐仁立[1] 解芸菲[1] 孙婵[1] 王勇[1] 孙超[1] 

机构地区：[1]西北农林科技大学动物科技学院,陕西杨凌712100

出　　处：《西北农林科技大学学报（自然科学版）》2011年第8期1-8,共8页Journal of Northwest A&F University(Natural Science Edition)

基　　金：教育部新世纪优秀人才计划项目(NCET-06-0865)

摘　　要：【目的】研究大肠埃希菌脂多糖(LPS)感染对乌鸡脂肪代谢及相关调控基因转录表达的影响。【方法】将120只35日龄乌鸡随机分为对照组和3个试验组(低剂量LPS组、中剂量LPS组、高剂量LPS组),试验组乌鸡每48 h注射1次不同浓度的大肠埃希菌LPS生理盐水溶液,剂量为1 mL/(只.次),低、中、高剂量LPS组乌鸡的LPS用量分别为0.25,0.5,1 mg/(kg.次),对照组注射等量生理盐水,持续2周。每次注射后12 h,用温度计测量鸡只泄殖腔温度;35,42,49日龄时称鸡体质量;49日龄时,各组随机选取10只鸡翅下静脉采血,分离血清,试剂盒检测血脂指标和脂解酶的活性,然后屠宰,取胸部肌肉、腿部肌肉和腹部脂肪计算脂肪沉积率,定量PCR检测脂肪和肌肉中脂肪代谢调控基因和脂肪酸转运调控基因的转录表达情况。【结果】试验期内LPS处理组乌鸡的泄殖腔温度极显著高于对照组;与对照组相比,LPS处理组乌鸡生产性能极显著下降;脂肪沉积量减少,肌间脂肪、皮下脂肪和腹部脂肪的含量明显降低;血清中总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)浓度极显著下降,而甘油三酯(TG)、游离脂肪酸(FFA)浓度极显著升高;LPS处理组乌鸡血清中的脂蛋白脂酶、肝脂酶和脂肪酶的活性均极显著高于对照组。定量PCR检测表明,LPS处理组乌鸡肌肉和脂肪中的脂肪合成基因FAS、ACC以及控制脂肪酸氧化的CPT-ⅠmRNA水平都显著下降,且FAS/CPT-ⅠmRNA表达水平的比率明显降低;而调控脂肪分解的LPL和控制能量稳态的PPARα的mRNA水平在低剂量LPS组明显升高,但在高剂量LPS组又显著降低;LPS处理组乌鸡的脂肪酸转运调控基因FATP1、FATP4随着LPS剂量的增大而显著降低,FABP和FAT/CD36mRNA在低剂量LPS组显著升高,但随着LPS剂量升高,其表达又降低。【结论】低剂量LPS处理减弱了乌鸡体内的脂肪生成和脂肪酸的氧化,强化了脂�【Objective】 This study was to investigate the effects of the inflammation indeuced by Escherichia coli lipopolysaccharides（LPS） on the lipid metabolism and the expression of genes of black-bone chicken.【Method】 120 35-day-old Sichuan black-bone chicken were randomly divided into 4 groups,treatment groups were injected with three different concentrations of E.coli LPS solution（low 0.25 mg/kg,middle 0.5 mg/kg,high 1 mg/kg） for every 48 h,respectively,and the control group was injected with equal volume of saline.The cloacal temperature of chicken was measured at 12 h after injection and body weight was measeured at the age of 35,42 and 49 days.Chickens were slaughtered after 2 weeks,chest muscle,leg muscle and abdominal fat were obtained for measurement of fat accumulation.Contents of total cholesterol（TC）,triglycerides（TG）,high density lipoprotein cholesterol（HDL-C）,low density lipoprotein cholesterol（LDL-C）,FFAs as well as the activity of enzymes in serum were measured by Kits.The mRNA expression levels of lipometabolism and FA transport genes in muscle and adipose were analyzed by Realtime-PCR.【Result】 Infection with the LPS markedly raised the cloacal temperature of chicken while decreased the performance and fat accumulation.Compared with the control,LPS challenged birds had lower concentrations of TC,HDL-C and LDL-C and higher concentrations of TG and FFAs.Moreover,the LPS increased the activity of lipoprotein lipase,hepatic lipase and lipase in chicken serum.PCR results showed that the mRNA levels of FAS,ACC and CPT-Ⅰ in muscle and adipose were down-regulated by the LPS,and the ratio between FAS and CPT-Ⅰ mRNA levels was markedly attenuated.However,the mRNA levels of LPL and PPARα were up-regulated by the low concentration LPS while down-regulated by the high concentration.Likewise,the mRNA expression of FATP1,FATP4 was down-regulated LPS while the mRNA levels of FABP and FAT/CD36 were up-regulated by the low concentration LPS,and down-regulated by the high concentrat

关 键 词：脂多糖 脂肪代谢 脂肪酸转运 乌鸡 

分 类 号：S831.1[农业科学—畜牧学]