心血管疾病為慢性腎病及末期腎病患者中相當常見的併發及死亡原因之一，其中血管鈣化為一個重要的危險因子。本研究探討腸道微生物群對於血管鈣化對於末期腎病患者心血管疾病的影響。實驗材料使用之糞便檢體，分別來自於健康對照組、控制良好鈣磷乘積產物的血液透析患者(HD)以及具有高鈣磷乘積產物的血液透析患者(HDHCP)，並對這些組別進行了16S片段定序再進行後續腸道微生物組成分析。 結果顯示，腸道微生物組成在健康對照組和血液透析患者中存在著顯著差異。在血液透析患者的菌相中，厚壁菌門、放線菌門以及變形菌門在豐度上有明顯增加。而在高鈣磷乘積產物組中，厚壁菌門中的一種菌屬Lachnospiraceae_FCS020_group，比起其他組別，則有顯著的增加。除了偵測腸道微生物組成變化外，我們利用PICRUSt軟體來預測功能性分析，發現HDHCP組中有幾個與血管鈣化相關的代謝途徑明顯差異，包括糖醣磷酸途徑、類固醇及萜烯骨架生物合成途徑與脂肪酸鏈的延長合成的上調。我們的研究結果證明了腸道微生物菌相的改變以及其代謝物，在末期腎病患者血管鈣化過程中扮演著重要角色，並對鈣磷乘積產物的生成具有潛在影響。某些微生物的增加和特定代謝途徑可能會影響末期腎病患者中的血管鈣化程度。

This study investigated the impact of gut microbiota on vascular calcification (VC), a cardiovascular risk factor in end-stage renal disease (ESRD). Fecal samples were collected from healthy controls, dialysis patients with controlled Ca x P, and dialysis patients with higher Ca x P (HDHCP). The samples were subjected to 16S amplicon sequencing to analyze the gut microbial composition. The results showed significant differences in gut microbial composition between hemodialysis patients and healthy controls. Three phyla (Firmicutes, Actinobacteria, and Proteobacteria) were notably more abundant in hemodialysis patients. Within the group with higher Ca x P, a specific genus called Lachnospiraceae_FCS020_group was significantly increased. Serval metabolic pathway, as predicted by the PICRUSt software, including the pentose phosphate pathway, the steroid biosynthesis pathway, the terpenoid backbone biosynthesis pathway and fatty acid elongation pathway, were found to be upregulated in the higher Ca x P group. Our research highlights the significance of dysbiosis in the gut microbiome of hemodialysis patients and its potential influence on Ca x P levels. We observed an elevated presence of specific microbial taxa and the upregulation of certain metabolic pathways. These findings suggest that these factors may play a role in the development of VC, a known cardiovascular risk factor in individuals with ESRD.

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