肠道菌群介导贞术调脂胶囊抑制去势小鼠骨丢失的机制研究

Study on the Mechanism of FTZ on bone loss in ovariectomized mice via gut microbiota

目的基于肠道菌群的变化,探讨贞术调脂胶囊(FTZ)抑制去卵巢(OVX)小鼠骨丢失的作用机制。方法选取18只11周C57BL6/J雌性小鼠,平均分为假手术组(SHAM组)、OVX组和FTZ组。FTZ组在OVX基础上给予FTZ[1.55 g/(kg·d)]灌胃,SHAM组和OVX组以等剂量0.9%氯化钠溶液灌胃,12周后收集小鼠左侧股骨、血清和粪便标本。左侧股骨行Micro-CT扫描;采用ELISA法检测血清中TNF-α、IL-10、IL-6、LPS和TRACP5b的含量;末次灌胃结束24 h后收集小鼠粪便,提取并检测粪菌总DNA,利用16 S rRNA高通量肠菌基因测序技术,对标本中的细菌16 S rRNA基因V3-V4可变区进行定性分析和OUT分析。结果与SHAM组相比,OVX组BV/TV、Tb.N、BMD和IL-10均显著性降低(P<0.05),Tb.Sp、TNF-α、IL-6、LPS和TRACP5b显著性增高(P<0.05);与OVX组相比,FTZ组Tb.N和IL-10显著性增高(P<0.05),Tb.Sp、TNF-α、IL-6和TRACP5b显著性降低(P<0.05)。在门水平,OVX组Firmicutes/Bacteroidota(F/B)率较SHAM组有增高趋势(P=0.310),但无显著性差异,而与OVX组相比,FTZ组F/B率显著性降低(P=0.002)。在属水平,与SHAM组相比,Faecalibaculum和Coriobacteriaceae_UCG-002丰度在OVX组中显著减少(P=0.030,P=0.005),Lachnoclostridium丰度在OVX组中显著增加(P=0.037),而与OVX组相比,FTZ组Faecalibaculum和Coriobacteriaceae_UCG-002丰度显著增加(P=0.045,P=0.005),Lachnoclostridium丰度显著减少(P=0.013)。结论FTZ能够延缓去势小鼠骨量丢失,其机制可能是通过调节肠道菌群中Faecalibaculum、Coriobacteriaceae_UCG-002和Lachnoclostridium丰度实现的,且同时抑制炎性反应。

Objective To investigate the regulatory mechanism of FTZ inhibiting bone loss in ovariectomized(OVX)mice based on the changes of gut microbiota.Methods Eighteen 11-week-old C57BL6/J female mice were randomly divided into three groups:SHAM group(n=6)and OVX group(n=6)received an equal dose of 0.9%NaCl in the same manner;FTZ group(n=6)received FTZ at a dose of 1.55 g/kg/d via oral gavage.After 12 weeks of intervention,the outcomes were changes in bone microstructures as measured by Micro-CT scanning analysis,serum parameters(TNF-α,IL-10,IL-6,LPS and TRACP5b)and gut microbiota were measured by ELISA and 16 S rRNA sequencing respectively.Results Compared with SHAM group,BV/TV,Tb.N,BMD and concentration of IL-10 were significantly decreased(P<0.05);Tb.Sp and concentration of TNF-α,IL-6,LPS and TRACP5b were significantly increased(P<0.05)in OVX group.The Tb.N and IL-10 were significantly increased(P<0.05),Tb.Sp,TNF-α,IL-6 and TRACP5b were significantly decreased in FTZ group compared with OVX group(P<0.05).At the phylum level,there was an increasing trend in F/B ratio(P=0.310)in OVX group compared with SHAM group.F/B ratio was significantly lower in FTZ group compared with OVX group(P=0.002).At the genus level,Faecalibaculum and Coriobacteriaceae_UCG-002 were significantly decreased(P=0.030,P=0.005)and Lachnoclostridium was significantly increased(P=0.037)in OVX group compared with SHAM group.Faecalibaculumand and Coriobacteriaceae_UCG-002 were significantly increased(P=0.045,P=0.005)and Lachnoclostridium was significantly decreased(P=0.013)in FTZ group.Conclusion FTZ can alleviate bone loss in OVX mice may be achieved by regulating the abundance of Faecalibaculum,Coriobacteriaceae_UCG-002 and Lachnoclostridium,meanwhile ameliorating the inflammatory response.