Table 1.
Author Reference | Country | Study Design | Participants | Changes in the Composition of Gut Microbiota in NAFLD | Key Findings |
---|---|---|---|---|---|
[38] | France | Cross-sectional study | 57 NAFLD 35 NASH |
↑ Actinobacteria ↑ Bacteroides ↑ Ruminococcus ↓ Prevotella No change in Firmicutes |
↑ Ruminococcus
was significant in NASH Gut microbiota can be one of the prognostic tools to evaluate NAFLD progression and severity |
[40] | Canada | Prospective cross-sectional study | 33 NAFLD: 11 simple steatosis 22 NASH 17 healthy controls |
↑ C. Coccoides in NASH ↓ Bacteroidetes in NASH compared to the SS and HCC |
The relationship between Bacteroidetes and liver disease state was not dependent on the increase in BMI or diet |
[41] | United States | Cross-sectional study | 44 NAFLD 29 healthy controls |
↓ Bacteroidetes ↓ Prevotella ↓ Gemmiger ↓ Oscillospira |
↓ Bacterial diversity in patients with NAFLD compared to controls contributed to an increase in the rate of inflammation in NAFLD |
[35] | United States | Prospective, observational, cross-sectional study | 87 NAFLD 37 healthy controls |
↑ Bacteroidetes ↑ Proteobacteria ↓ Firmicutes |
↓ α-diversity in NAFLD was attributed to the differences in bacterial abundance rather than an increase in specific phyla or genus ↑ Pro-inflammatory bacterial products (LPS) in patients with NAFLD |
[36] | United States | Case-control | 22 NASH 25 obese 16 healthy controls |
↑ Bacteroides (Prevotella) ↑ Proteobacteria (Escherichia) ↓ Firmicutes ↓ Actinobacteria |
↑ Abundance of ethanol producing bacteria (Escherichia) in patients with NASH contributed to disease progression ↑ Ethanol-producing bacteria (Escherichia) was attributed to the use of antibiotics |
[39] | Italy | Case-control | 61 NASH/NAFL 54 healthy controls |
↑ Actinobacteria ↑ Bradyrhizobium ↑ Anaerococcus ↑ Peptoniphilus ↑ Propionibacterium acnes ↑ Enterobacteriaceae (Escherichia coli) ↑ Dorea ↑ Ruminococcus ↓ Bacteroidetes ↓ Oscillospira ↓ Rikenellaceae |
↓ Microbial diversity in NASH/NAFL ↓ Bacteroidaceae and Bacteroides were in NAFL and NASH, while it ↑ in obese patients compared to controls ↑ Ethanol-producing bacteria (Enterobacteriaceae) in NAFL/NASH compared to controls |
[37] | Canada | Case-control | 30 NAFLD 30 healthy controls |
↑ Proteobacteria ↑ Firmicutes ↓ Bacteroidetes |
Fecal ester volatile organic compounds could influence the microbiome composition of patients with NAFLD in an unfavorable way |
BMI, body mass index; HCC, hepatocellular carcinoma; LPS, lipopolysaccharide; NAFL, nonalcoholic fatty liver; NAFLD, nonalcoholic fatty liver disease; NASH, nonalcoholic steatohepatitis; SS, steatohepatitis; ↑, increase; and ↓, decrease.