Effects of gut microbiota and gut-derived lipopolysaccharide on patients with coronary heart disease

Abstract

Background: To research the associations between gut microbiota composition, lipopolysaccharide (LPS), and atherosclerosis in process of coronary heart disease（CHD） Methods: We enrolled 50 patients who had been given a traditional coronary angiography diagnosis of coronary heart disease in the CHD group, and 50 matching patients who had CHD excluded in the control group. The CHD patients were further classified into three groups based on their Gensini scores, which were determined using the modified scoring schema: a mild CHD group (26 scores, N=16), a moderate CHD group (26-54 scores, N=23), and a severe CHD group (>54 scores, N=11). The DNA of the gut microbiota was then extracted from their excrement. 16S rRNA sequencing was used to compare the differences in the bacteria between the two groups. BugBase and Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) were used to predict the functional composition of the bacteria. In addition, The level of plasma LPS and serum proinflammatory cytokines in the two groups was measured. Results: Plasma LPS and serum IL-1β, IL-6, and TNF-α concentrations were significantly higher in patients with CHD and significantly different among mild CHDgroup, moderate CHDgroup, and severe CHDgroup(all P＜0.05). There was no difference in the diversity of gut microbiota among the two groups (P＞0.05). At the phylum level, Bacteroidetes were more numerous in the control group. At the genus level, Enterococcus, Butyrivibrio, Dolosigranulum, Pseudomonas, and Anaerotignum were more numerous in the CHD group whereas Enterobacter, Parabacteriodes, Lachnoclostridium, Streptococcus were more numerous in the control group. PICRUSt analysis found that the level of LPS choline phosphotransferase (licD) gene expression and LPS biosynthesis correlated with LPS production was higher in the fecal microbiome of the CHD group(P＜0.05). Conclusion: The gut microbiota and LPS play a vital role in the development of atherosclerosis through its metabolites, which were anticipated to develop into a CHD diagnostic marker and unique treatment approach.