Characterizing the gut microbiota composition in Taiwanese hypertensive patients using 16S rRNA sequencing analysis

Abstract Objective Hypertension (HTN) is a significant risk factor for cardiovascular and cerebrovascular diseases. Accumulating evidence suggests a close relationship between HTN and dysbiosis of the gut microbiota. Methods In the present study, we recruited 23 HTN patients and 17 controls matched for demographic characteristics. DNA extracted from fecal samples of patients was subjected to Illumina MiSeq sequencing, targeting the V3-V4 region of the bacterial 16S rRNA gene for analysis. We compared the diversity and composition of gut microbiota between the two groups. Results The α-diversity of gut microbiota in HTN patients was similar to that in the control group. β-diversity analysis showed slight differences in microbial composition between the HTN and control groups. We used Welch's t -test to evaluate the significant difference in the bacterial composition of the top 20 ASVs between the HTN group and the control group, and the results showed that Tyzzerella was significantly increased, while Faecalibacterium was significantly decreased in the HTN group. We also conducted the Kruskal-Wallis test to compare the significant differences between the HTN group and the control group at various taxonomic levels (phylum, class, order, family, genus, and species). The results revealed that a significant reduction in the abundance of Faecalibacterium , Lachnospiraceae_UCG-004 , Coprobacter , and Alphaproteobacteria in the HTN group compared to the control group. Additionally, Linear Discriminant Analysis Effect Size (LEfSe) results showed significant enrichment of Enterobacteriaceae in the HTN group, whereas Alphaproteobacteria , Lachnospiraceae_UCG_004 , and Faecalibacterium dominated in the control group. As Faecalibacterium exhibited lower abundance in the HTN group according to the above results, we performed PCR using Faecalibacterium -specific primers and analyzed their levels through agarose gel electrophoresis, confirming the reduced abundance of Faecalibacterium in the HTN group. In addition, Tax4Fun2 analysis was employed to examine differences in microbial functionality between the HTN group and the control group. Conclusion We studied the fecal microbiota of hypertensive population in Taiwan through 16S rRNA gene sequencing, and found that Faecalibacterium has a lower abundance in hypertensive patients. This unique alteration in gut microbiota may provide insights into the pathogenesis of HTN and aid in the development of novel biomarkers and therapeutic targets.