佐剂性关节炎大鼠肠道G蛋白耦联受体43、短链脂肪酸的表达及相关性分析

Expressions of and correlation between GPR43 and short-chain fatty acids in intestinal tract of rats with adjuvant arthritis

目的观察佐剂性关节炎(AA)大鼠肠道短链脂肪酸(SCFAs)、G蛋白耦联受体43(GPR43)的变化并分析二者之间的相关性。方法Wistar雄性大鼠被随机分为正常组(NC组)、模型组(AA组),每组8只。模型组大鼠采用弗氏完全佐剂(CFA)注射法复制AA模型。复制成功后观察各组大鼠关节肿胀度(JSD)、关节炎指数(AI)的变化;采用透射电镜观察各组大鼠踝关节滑膜细胞结构的改变;使用蛋白质印迹法检测各组大鼠结肠组织中GPR43的水平;应用液相色谱—质谱联用(LC-MS/MS)检测粪便中菌群代谢物SCFAs水平。结果与NC组相比,AA组大鼠足趾部红肿明显,JSD(t’=15.046,P<0.001)、AI评分(t’=23.910,P<0.001)均显著升高,滑膜病理损伤明显,线粒体形态评分升高(z=2.023,P<0.050);AA组结肠组织GPR43相对表达量降低(t=3.182,P<0.050),粪便丁酸(t’=4.798,P<0.010)、己酸(t=4.123,P<0.010)水平显著降低,其余SCFAs差异无统计学意义。结肠组织GPR43水平与大鼠粪便丁酸(r=0.817,P<0.050)、己酸(r=0.789,P<0.050)存在线性相关关系。结论AA大鼠粪便丁酸、己酸水平及结肠组织GPR43相对表达量均下降,且结肠组织GPR43水平与粪便丁酸、己酸水平呈正相关。

Objective To observe the changes of intestinal short-chain fatty acids(SCFAs)and G-protein-coupled receptor 43(GPR43)and analyze the correlation between them in adjuvant arthritis(AA)rats.Methods Wistar male rats were randomly divided into normal group(NC group)or model group(AA group),with 8 rats in each group.In AA group,the AA model rats were replicated by using the Fuchs'complete adjuvant(CFA)injection method.After successful replication,the changes of joint swelling degree(JSD)and arthritis index(AI)were observed in each group;the changes in the cellular structure of synovial membrane of ankle joint in each group were observed with transmission electron microscopy.GPR43 in the colon tissue was detected with protein blotting;the content of colony metabolites SCFAs in feces was detected using liquid chromatography-tandem spectrometry(LC-MS/MS).Results Compared with NC group,the rats in AA group had obvious redness and swelling of toes,significantly higher JSD(t'=15.046,P<0.001)and AI scores(t'=23.910,P<0.001),obvious pathological damage of synovium,and higher mitochondrial morphology scores(z=2.023,P<0.050).The relative expression of GPR43 in the colon tissue reduced in the AA group(t=3.182,P<0.050),and the contents of fecal butyric acid(t'=4.798,P<0.010)and hexanoic acid(t=4.123,P<0.010)significantly reduced;the difference between the remaining SCFAs was not statistically significant.There was a linear correlation between GPR43 level in colon tissue and fecal butyric acid(r=0.817,P<0.050)and caproic acid(r=0.789,P<0.050)in the rats.Conclusion The levels of fecal butyric acid and hexanoic acid as well as the relative expression of GPR43 in the colon tissues decreased in rats with adjuvant arthritis,and there was a positive correlation between the level of GPR43 in the colon tissues and the levels of fecal butyric acid and hexanoic acid.