高脂饮食诱导的肥胖及其脂肪细胞外泌体对年轻小鼠创伤性膝关节炎的影响及机制研究  

Effect of obesity induced by high-fat diet and adipose exosomes on knee post-traumatic osteoarthritis caused by destabilization of medial meniscus surgery in young mice

作　　者：吴立桐 李保超 姚波 华子春[3,4] WU Li-tong;LI Bao-chao;YAO Bo;HUA Zi-chun(Nanjing Foreign Language School,Nanjing 210008,China;Nanjing Stomatological Hospital,Affiliated Stomatological Hospital,Medical School,Nanjing University,Nanjing 210019,China;School of Life Sciences,Nanjing University,Nanjing 210023,China;Jiangsu Society of Biochemistry and Molecular Biology and Nanjing Genrecom Laboratories,Ltd.,Nanjing 211899,China)

机构地区：[1]南京外国语学校,江苏南京210008 [2]南京大学医学院附属口腔医院,南京市口腔医院,江苏南京210019 [3]南京大学生命科学学院,江苏南京210023 [4]江苏省生物化学与分子生物学学会和南京吉芮康生物科技研究院,江苏南京211899

出　　处：《药学学报》2023年第8期2415-2423,共9页Acta Pharmaceutica Sinica

基　　金：中国科协中学生英才计划生物项目(2022年度);国家自然科学基金资助项目(82130106);江苏省卫健委重点项目(ZD2022025).

摘　　要：肥胖是膝关节炎的重要风险因素,但其对于青少年创伤性骨关节炎的影响仍有待于进一步研究。除了机械负重,其内在机制是否和脂肪组织外泌体的远程调控相关?为明确高脂饮食诱导的肥胖及其分泌的脂肪组织外泌体对年轻小鼠创伤性膝关节炎的影响作用,本研究首先将20只6周龄C57BL/6J年轻小鼠随机分为正常饮食组(control diet,CD组)、内侧半月板失稳术(destabilization of medial meniscus,DMM)手术组、高脂饮食组(high fat diet,HFD组)及高脂饮食加DMM手术组(HFD+DMM组),每组5只小鼠。CD和DMM组喂养常规饲料,HFD和HFD+DMM组喂养高脂饲料。在小鼠10周龄时进行DMM手术或假手术。提取高脂饮食组和正常饮食组小鼠脂肪组织外泌体(exosomes,Exo),进行体外鉴定,荧光标记活体成像。然后,本研究将15只6周龄C57BL/6J小鼠随机分为DMM组、DMM加肥胖小鼠脂肪组织外泌体注射组(DMM+HFD-Exo组)及DMM加正常小鼠脂肪细胞外泌体注射组(DMM+CD-Exo组),每组5只小鼠。DMM+HFD-Exo组与DMM+CD-Exo组小鼠进行外泌体尾静脉注射,每周一次(每次100μL,浓度为1μg·μL^(-1))。本研究动物福利和实验过程均遵循南京大学实验动物伦理委员会的规定(批准号:IACUC-D2204005)。所有组别的小鼠于18周时终止实验,取膝关节软骨组织进行固定,行micro CT检测,测量骨体积分数、骨小梁厚度、骨小梁数目和骨小梁分离度。然后再将组织标本脱钙,制成4μm的石蜡切片,进行H&E及番红O固绿染色,观察小鼠膝关节的组织形态学变化。结果显示,与正常饮食组相比,高脂饮食诱导的肥胖能显著加重年轻小鼠创伤性膝关节炎的病理变化,表现为软骨Mankin评分增加,软骨表面粗糙,软骨下骨硬化增加;肥胖组织外泌体能加重DMM手术诱导的软骨病理变化,但不加重软骨下骨病变。因此,高脂饮食诱导的肥胖可以显著加重DMM手术诱导的年轻小鼠的创伤性膝关节炎,其�Obesity is an important risk factor related to osteoarthritis,but it′s role in post-traumatic osteoarthritis on young people need to further study.The internal mechanism except the mechanical loading may be associated with adipose exosomes.To examine the effect of obesity induced by high fat diet and adipose exosomes on knee post-traumatic osteoarthritis caused by destabilization of medial meniscus(DMM)surgery in young mice,206-week-old C57BL/6J mice were randomly assigned to the control diet group(CD,n=5),the DMM group(n=5),the high fat diet group(HFD,n=5)and the HFD plus DMM group(HFD+DMM,n=5).The CD and DMM group were fed with a control diet,and the HFD and HFD+DMM group were fed with a high fat diet.We did the DMM surgery and the sham surgery on the mice when it was 10 weeks old.Extract obese and normal adipose exosomes,identify exosomes in vitro,and proceed fluorescence imaging in vivo using DiR staining.DMM+HFD-Exo group and DMM+CD-Exo group were injected the exosomes from the tail vain once a week(100μL per shot with a concentration of 1μg·μL^(-1)).Second,156-week-old C57BL/6J mice were randomly assigned to the DMM group(n=5),the DMM plus obese adipose exosomes group(DMM+HFD-Exo,n=5),and the DMM plus control diet adipose exosomes group(DMM+CD-Exo,n=5).Animal welfare and experimental process are in accordance with the regulations of the Experimental Animal Ethics Committee of Nanjing University(IACUC-D2204005).All mice were sacrificed at the age of 18 weeks,the knee joints of the mice were harvested and fixed.We used micro CT to examine the samples and measured the bone volume/tissue volume,trabecular thickness,trabecular number and trabecular separation.Then the samples were decalcified and embedded in paraffin,and 4μm thickness sections were stained with H&E and safranin O/fast green to observe the histological changes of the knee joint.The results showed compared with the control diet group,high fat diet induced obesity can aggravate the pathological changes of the post-traumatic osteoarthritis ca

关 键 词：高脂饮食 肥胖 脂肪组织 外泌体 创伤性膝关节炎 

分 类 号：R966[医药卫生—药理学]