Gut Microbiota Interplay With COVID-19 Reveals Links to Host Lipid Metabolism Among Middle Eastern Populations

Abstract

The interplay between the compositional changes in the gastrointestinal microbiome, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) susceptibility and severity, and host functions is complex and yet to be fully understood. This study performed 16S rRNA gene-based microbial profiling of 143 subjects. We observed structural and compositional alterations in the gut microbiota of the SARS-CoV-2-infected group in comparison to non-infected controls. The gut microbiota composition of the SARS-CoV-2-infected individuals showed an increase in anti-inflammatory bacteria such as Faecalibacterium (p-value = 1.72 × 10–6) and Bacteroides (p-value = 5.67 × 10–8). We also revealed a higher relative abundance of the highly beneficial butyrate producers such as Anaerostipes (p-value = 1.75 × 10–230), Lachnospiraceae (p-value = 7.14 × 10–65), and Blautia (p-value = 9.22 × 10–18) in the SARS-CoV-2-infected group in comparison to the control group. Moreover, phylogenetic investigation of communities by reconstructing unobserved state (PICRUSt) functional prediction analysis of the 16S rRNA gene abundance data showed substantial differences in the enrichment of metabolic pathways such as lipid, amino acid, carbohydrate, and xenobiotic metabolism, in comparison between both groups. We discovered an enrichment of linoleic acid, ether lipid, glycerolipid, and glycerophospholipid metabolism in the SARS-CoV-2-infected group, suggesting a link to SARS-CoV-2 entry and replication in host cells. We estimate the major contributing genera to the four pathways to be Parabacteroides, Streptococcus, Dorea, and Blautia, respectively. The identified differences provide a new insight to enrich our understanding of SARS-CoV-2-related changes in gut microbiota, their metabolic capabilities, and potential screening biomarkers linked to COVID-19 disease severity.

Gut microbiota and COVID-19: A systematic review

“…In general, the main alternations in the gut microbiome of COVID-19 infected individuals were the higher abundance of; Bacteroides, Streptococcus, Fusobacterium, Campylobacter, Lactobacillus, Proteobacteria, Enterococcaceae, Enterococcus, Rothia, Pseudomonas, Veillonella, Clostridium, and Staphylococcaceae, and lower presence of; Coprococcus, Faecalibacterium, Eubacterium, Roseburia, Bi dobacterium, and Blautia. In our review, ve studies reported an increase in Bacteroides in COVID-19 patients [51,61,[78][79][80] while only one reported a decrease in them [42]. These studies observed a rise in Bacteroides stercoris, Bacteroides dorei, Bacteroides vulgatus, Bacteroides massiliensis, Bacteroides oleiciplenus, and Bacteroides ovatus as main species in fecal samples of COVID-19 patients.…”

“…was another common genus mentioned by four articles in our review. One study reported a decrease in the levels of this bacterium [75], while another study reported increasing patterns of this bacteria [42]; in addition, its presence in the gut microbiome of CRC patients has been linked to more severe disease [44] and increased levels of this bacterium have been reported after COVID-19 recovery [46]. In a similar study investigating the alterations of gut microbial composition among COVID-19 patients, the authors reported declining bene cial species and increasing opportunistic pathogens such asBlautia sp.…”

“…Five studies reported alterations in Streptococcus spp., in fecal samples of COVID-19 patients. Four studies reported increasing levels of this bacterium [29,42,61,73] and two articles speci ed Streptococcus thermophilus [61], and Streptococcus infantis [29] as the main increasing bacteriain COVID-19 patients' gut. On the other hand, two studies reported a decrease in this bacterium level[61, 69]; Li et al speci ed Streptococcus salivarius as the main decreasing species [61].…”

“…Four studies stated a decrease in Bi dobacterium genus in COVID-19 patients' gut microbiome [42,69,78,79] while only one study reported an increase in this genus [61]. Although Bi dobacterium longum was reported as the main increasing species [61], Bi dobacterium adolescentis was reported by another study as the decreasing bacteria [79].…”

Immune Profiling of COVID-19 in Correlation with SARS and MERS

“…Similarly, SARS-CoV-2 uses the S protein to bind ACE2, yet attaches to the host cell with a higher affinity compared to SARS-CoV [44][45][46][47]. ACE2 is expressed on a variety of cells in the lungs and the gut, including epithelial cells of the airways and alveoli, vascular endothelial cells, and macrophages [48][49][50][51]. The transmembrane serine protease 2 (TMPRSS2) is also needed for SARS-CoV-2 entry [52].…”