宰后成熟过程中脂多糖诱导剂对滩羊肌细胞线粒体凋亡信号通路的影响  

Effects of Lipopolysaccharide as an Inducer on the Mitochondrial Apoptosis Signaling Pathway in Tan Sheep Muscle Cells during Postmortem Aging

作　　者：李荣[1] 罗瑞明[1] 杜瑞 罗玉龙 王金霞 张倩[1] 陈雪妍 LI Rong;LUO Ruiming;DU Rui;LUO Yulong;WANG Jinxia;ZHANG Qian;CHEN Xueyan(School of Food Science and Engineering,Ningxia University,Yinchuan 750021,China;Yinchuan Agricultural Products Quality Testing Center,Yinchuan 750000,China)

机构地区：[1]宁夏大学食品科学与工程学院,宁夏银川750021 [2]银川市农产品质量检测中心,宁夏银川750000

出　　处：《食品科学》2023年第19期10-17,共8页Food Science

基　　金：国家自然科学基金青年科学基金项目(32202135);宁夏青年科技人才托举工程项目。

摘　　要：为探究脂多糖(lipopolysaccharide,LPS)诱导剂对滩羊肌细胞线粒体信号通路的影响,以6月龄滩羊背最长肌(M longissimus dorsi)为研究对象,分析其4℃成熟0、6、12、24、72 h时pH值、ATP含量、细胞凋亡率、细胞凋亡酶活力、琥珀酸脱氢酶(succinatedehydrogenase,SDH)和柠檬酸合酶(citrate synthase,CS)活力、Bcl-2家族蛋白含量、细胞凋亡因子细胞色素c(cytochrome c,Cyt-c)和半胱氨酸蛋白酶3(cysteinyl aspartate specific proteinase 3,Caspase-3)表达量的变化情况。结果表明,宰后成熟过程中,对照组和LPS诱导处理组滩羊肌肉中细胞凋亡率、Bax/Bcl-2的比值呈显著上升趋势(P<0.05);Caspase-3和Caspase-9活力均呈现先上升后下降趋势,经LPS处理后,滩羊肉骨骼肌中Caspase-3和Caspase-9活力均在任一时间点均高于对照组;pH值、Cyt-c还原水平和线粒体ATP含量整体呈现显著下降趋势(P<0.05);对照组和处理组胞浆Cyt-c相对表达量在宰后12 h较初始水平显著升高,24~72 h内LPS处理组胞浆Cyt-c相对表达量呈现下降趋势;同一时间LPS处理组的Caspase-3活化片段蛋白相对含量均高于对照组。结论:滩羊宰后成熟过程中LPS诱导剂对线粒体信号通路的影响是通过激活Caspase-9和Caspase-3的活性、降低线粒体ATP含量从而导致能量代谢水平降低,进而影响SDH和CS的活性,促使Cyt-c的释放,提高Bax/Bcl-2的比值,最终诱导细胞通过线粒体信号通路发生凋亡。In order to investigate the effects of lipopolysaccharide(LPS)on the mitochondrial signaling pathway in muscle cells of Tan sheep,M longissimus dorsi muscles from six-month-old Tan sheep were aged at 4℃for 0,6,12,24 and 72 h postmortem and evaluated for pH,ATP content,cell apoptosis rate,cell apoptosis-related enzyme activity,succinatedehydrogenase(SDH)activity,citrate synthase(CS)activity,B-cell lymphoma 2(Bcl-2)family protein contents,and cytochrome c(Cyt-c)and cysteinyl aspartate specific proteinase 3(Caspase-3)expression levels.The results showed that the apoptosis rate and Bcl-2-associated X protein(Bax)/Bcl-2 ratio in the control and LPS-induced groups were significantly increased during postmortem aging(P<0.05).The activities of Caspase-3 and Caspase-9 increased first and then decreased.After LPS treatment,the activities of Caspase-3 and Caspase-9 were higher than those in the control group at all time points.The pH,Cyt-c reduction level and mitochondrial ATP content were significantly decreased overall(P<0.05).The relative expression level of Cyt-c was significantly increased in both groups at 12 h postmortem,and decreased during 24–72 h in the LPS group.The content of Caspase-3 activated fragment protein in the LPS treatment group was higher than that in control group at the same time points.In conclusion,LPS could activate Caspase-3 and Caspase-9,and reduce the mitochondrial content of ATP and consequently energy metabolism level,thus affecting the activities of SDH and CS,promoting the release of Cyt-C,and increasing Bax/Bcl-2 ratio,and finally inducing cell apoptosis through the mitochondrial signaling pathway.

关 键 词：滩羊 脂多糖 细胞凋亡 线粒体通路 

分 类 号：TS251.53[轻工技术与工程—农产品加工及贮藏工程]