日粮中添加沙棘果渣对肉羊肌内脂肪沉积及其关键基因和酶活力的影响  

Effect of Dietary Seabuckthorn Pomace Supplementation on Intramuscular Fat Deposition Related Gene Expression and Enzyme Activity in Lambs

作　　者：邓步皓 秦旭泽 张婷 张建新[1] 赵俊星[1] DENG Buhao;QIN Xuze;ZHANG Ting;ZHANG Jianxin;ZHAO Junxing(College of Animal Science,Shanxi Agricultural University,Taigu 030801)

机构地区：[1]山西农业大学动物科学学院,太谷030801

出　　处：《激光生物学报》2020年第5期475-480,F0003,共7页Acta Laser Biology Sinica

基　　金：国家肉羊产业技术体系专项项目(CARS-38);国家自然科学基金项目(31972559)。

摘　　要：本文旨在研究日粮中添加沙棘果渣(SBP)对肉羊肌内脂肪沉积的影响及作用机制。试验随机选择4月龄,体重相近的杜泊×小尾寒羊杂交公羊30只,平均分为3组,饲喂添加含不同SBP的日粮:0%(对照组)、7.8%(7.8SBP组)和16.0%(16SBP组)。试验采用索氏提取法测定肌内脂肪含量,马森(Masson)三色染色法测定肌内脂肪细胞数量;同时运用实时定量荧光PCR(real time qPCR)与蛋白质印迹法(Western blot)对脂肪细胞分化、脂肪酸代谢相关关键基因及蛋白进行分析;并采用酶联免疫吸附测定(ELISA)分析了脂肪酸合成和降解的关键酶活性。研究结果表明,与对照组相比,7.8SBP组和16SBP组剪切力极显著降低(P<0.01)。16SBP组背最长肌中粗脂肪含量显著上升(P<0.05),成熟脂肪细胞数目显著增加(P<0.05)。与对照组相比,16SBP组的ZNF423(P<0.05)、PPARγ(P<0.05)和C/EBPα(P<0.01)等脂肪细胞分化关键基因的mRNA表达量增加,同时C/EBPα(P<0.05)和PPARγ(P<0.05)蛋白的表达量显著提高。16SBP组的SREBP1 mRNA含量显著高于对照组(P<0.05),而7.8SBP组与16SBP组的SREBP1蛋白表达量均显著(P<0.05)高于对照组。16SBP组中FAS mRNA(P<0.05)含量与酶活性(P<0.05)均显著高于对照组,乙酰辅酶A羧化酶(ACC)蛋白(P<0.05)含量与酶活性(P<0.05)也显著高于对照组。与对照组相比,16SBP组中激素敏感脂肪酶(HSL)的酶活力显著降低(P<0.05),而苹果酸脱氢酶(MDH)与脂蛋白脂酶(LPL)活性未见显著差异。试验结果表明,饲料中添加16%SBP可以有效提高羊肉嫩度,促进脂肪细胞的生成与改善脂肪酸代谢相关酶类活性,最终促进肌内脂肪的沉积。The objective of the present study was to determine the effects and mechanisms of dietary sea buckthorn pomace(SBP)supplementation on intramuscular fat(IMF)accumulation in LD muscle of ram lambs.A total of 30 Dorper×thin-tailed crossed ram lambs(4 months old)were randomly selected and equally assigned into 3 groups:control,7.8SBP and 16SBP,which received 3 levels of SBP supplementation(0%,7.8%and 16%).After experiment,the crude fat was determined by Soxhlet extraction,the number of mature adipocytes were determined by Masson trichrome staining.The real time-qPCR were used to determine key gene’s expression and Western blotting were used to analyze protein alteration.Additionally,ELISA was employed to analyze enzyme’s activity.Compare with control lambs,the WBSF in both 7.8SBP and 16SBP groups were decreased(P<0.01).The crude fat content in LD muscle of 16SBP was increased(P<0.05),together with higher mature adipocytes number(P<0.05).The mRNA content of key adipogenic related genes,including ZNF423(P<0.05),PPARγ(P<0.05)and C/EBPα(P<0.01)were upregulated by the supplementation of 16%SBP.Consistently,both the C/EBPαand PPARγcontent in LD muscle of lambs were higher compared with those from control group.SREBP1 was unregulated(P<0.05)in LD muscle of 16SBP lambs both at mRNA and protein level.Meanwhile,both mRNA(P<0.05)and enzymatic activity(P<0.05)of FAS were higher than that in control group.Moreover,ACC’s activity was significantly upregulated(P<0.05).Additionally,although both MDH and LPL activity were not affected by SBP supplementation,a reduced HSL activity was observed in lambs received 16%dietary SBP.Dietary 16%SBP supplementation effectively promoted intramuscular adipogenesis related transcriptional factors expression,and regulated triglyceride metabolisms through enzyme’s activity manipulation,which might be contributed to reduce WBSF.

关 键 词：肉羊 剪切力 沙棘果渣 肌内脂肪 基因表达 

分 类 号：S826[农业科学—畜牧学]