Comparison of Microbial Populations in the Blood of Patients With Myocardial Infarction and Healthy Individuals

Abstract

Increased bacterial translocation in the gut and bloodstream infections are both major comorbidities of heart failure and myocardial infarction (MI). However, the alterations in the microbiome of the blood of patients with MI remain unclear. To test this hypothesis, we conducted this case-control study to explore the microbiota compositions in the blood of Chinese patients with MI. Using high-throughput Illumina HiSeq sequencing targeting the V3–V4 region of the 16S ribosomal RNA (rRNA) gene, the microbiota communities in the blood of 29 patients with MI and 29 healthy controls were examined. In addition, the relationship between the blood microbiome and clinical features of MI was investigated. This study revealed a significant reduction in alpha diversity (Shannon index) in the MI group compared with the healthy controls. Also, a significant difference was detected in the structure and richness between the patients with MI and healthy controls. The members of the phylum Actinobacteria, class Actinobacteria, order Bifdobacteriales, family Bifidobacteriaceae, and genus Bifidobacterium were significantly abundant in the MI group, while the members of the phylum Bacteroidetes, class Bacteroidia, and order Bacteroidales were significantly enriched in the healthy controls (p < 0.05). Moreover, the functional analysis revealed a significant variation between both groups. For instance, the enrichment of genes involved in the metabolism pathways of three amino acids decreased, that is, nucleotide transport and metabolism, coenzyme transport and metabolism, and lipid transport and metabolism, among others. Our study will contribute to a better knowledge of the microbiota of blood, which will further lead to improved MI diagnosis and therapy. Further study is needed to determine the role of the blood microbiota in human health and disease.

Analysis of the blood bacterial composition of patients with acute coronary syndrome and chronic coronary syndrome

“…Considering multiple recent studies that showed changes in blood microbiota composition and diversity are linked to non-communicable diseases, by examining changes in blood microbial signature among acute coronary syndrome, chronic coronary syndrome, and Healthy group, we hope to determine the role of circulating microbiota on atherosclerosis. In addition, our results revealed that the patients with acute coronary syndrome and chronic coronary syndrome were significantly older than healthy individuals, these findings are similar to our previous results ( Khan et al., 2022b ), this suggests that another important factor influencing atherosclerosis is age, a detailed study worth needed to investigate the blood microbiota profile between young and aged individuals. Improving the accuracy of risk prediction is very important because it helps target those subjects who are most likely to benefit from preventive treatment.…”

“…DNA extraction and implication of V3-V4 regions of 16Sr RNA gene were amplified by using 338F: 5’-ACTCCTACGGGAGGCAGCA-3’ and 806R: 5’-GGACTACHVGGGTWTCTAAT-3’ universal primer set by following our previous study protocols ( Khan et al., 2022b ). Followed by Amplicons sequencing using Illumina Novaseq 6000.…”

Circulating microbiota and metabolites: Insights into cardiovascular diseases

“…Our study revealed a significant reduction in alpha diversity (Shannon index, p = 0.05), in the MI group when compared to the healthy controls. 20 More recently, we performed another study that confirmed that the patients with myocardial infarction including (acute coronary syndrome patients, and chronic coronary syndrome patients) were distinct blood microbial profiles. Our study observed a significantly higher alpha diversity (Chao1, p = 0.001 and Shannon indices, p = 0.004) in the acute coronary syndrome group compared with the chronic coronary syndrome and healthy group, although a significantly lower alpha diversity was observed in the chronic coronary syndrome compared to acute coronary syndrome and healthy group, and beta diversity analysis demonstrated a major separation among three groups.…”

“…During the last 2 years, numerous studies have been published on blood microbial composition and its association with human health and diseases. For instance, several recent studies demonstrated a significant role of the tissue microbiome in the onset of cancer, 13 other diseases, 14 pre‐diabetic and type 2 diabetic patients, 15 COVID‐19, 16 metabolic diseases, 17 portal hypertension, 18 polycystic ovary syndrome, 19 myocardial infarction, 20 acute coronary syndrome, and chronic coronary syndrome 21 . Moreover, microbial metabolites present in the gut include amino acid derivatives, hormones, short‐chain fatty acids (SCFAs), vitamins, and antioxidants 22 .…”

High fiber diet attenuate the inflammation and adverse remodeling of myocardial infarction via modulation of gut microbiota and metabolites

“…The trimmed sequences were then clustered into operational taxonomical units (OTUs) with a threshold of 97% by the UPARSE algorithm. Microbiota bacterial composition analysis was done in QIIME (version 2.0) according to previously published work ( Hu et al, 2021 ; Khan et al, 2022 ). The sequencing data for our study are available in the NCBI Sequence Read Archive under accession no.…”