Metabolic dysfunction-associated fatty liver disease (MAFLD) is a phenotype of liver diseases associated with metabolic syndrome. The pathogenesis MAFLD remains unclear. The liver maintains is located near the intestine and is physiologically interdependent with the intestine via metabolic exchange and microbial transmission, underpinning the recently proposed "oral-gut-liver axis" concept. However, little is known about the roles of commensal fungi in the disease development. This study aimed to characterize the alterations of oral and gut mycobiota and their roles in MAFLD. Twenty-one MAFLD participants and 20 healthy controls were enrolled. Metagenomics analyses of saliva, supragingival plaques, and feces revealed significant alterations in the gut fungal composition of MAFLD patients. Although no statistical difference was evident in the oral mycobiome diversity within MAFLD and healthy group, significantly decreased diversities were observed in fecal samples of MAFLD patients. The relative abundance of one salivary species, five supragingival species, and seven fecal species was significantly altered in MAFLD patients. Twenty-two salivary, 23 supragingival, and 22 fecal species were associated with clinical parameters. Concerning the different functions of fungal species, pathways involved in metabolic pathways, biosynthesis of secondary metabolites, microbial metabolism in diverse environments, and carbon metabolism were abundant both in the oral and gut mycobiomes. Moreover, different fungal contributions in core functions were observed between MAFLD patients and the healthy controls, especially in the supragingival plaque and fecal samples. Finally, correlation analysis between oral/gut mycobiome and clinical parameters identified correlations of certain fungal species in both oral and gut niches. Particularly, Mucor ambiguus, which was abundant both in saliva and feces, was positively correlated with body mass index, total cholesterol, low-density lipoprotein, alanine aminotransferase, and aspartate aminotransferase, providing evidence of a possible "oral-gut-liver" axis. The findings illustrate the potential correlation between core mycobiome and the development of MAFLD and could propose potential therapeutic strategies.
Experiment 1
Subjects
- Location of subjects
- China
- Host species Species from which microbiome was sampled. Contact us to have more species added.
- Homo sapiens
- Body site Anatomical site where microbial samples were extracted from according to the Uber Anatomy Ontology
- Saliva Sailva normalis,Saliva atomaris,Saliva molecularis,Salivary gland secretion,Saliva,saliva
- Condition The experimental condition / phenotype studied according to the Experimental Factor Ontology
- Non-alcoholic fatty liver disease fatty liver disease, nonalcoholic,fatty liver disease, nonalcoholic, susceptibility to, 1,liver disease, alcoholic, susceptibility to, 1,NAFLD - Nonalcoholic Fatty Liver Disease,NAFLD - nonalcoholic fatty liver disease,NAFLD1,non-alcoholic fatty liver,non-alcoholic fatty liver disease,Nonalcoholic Fatty Liver Disease,nonalcoholic fatty liver disease,Non-alcoholic fatty liver disease
- Group 0 name Corresponds to the control (unexposed) group for case-control studies
- Healthy control group
- Group 1 name Corresponds to the case (exposed) group for case-control studies
- Non-alcoholic fatty liver disease participants
- Group 1 definition Diagnostic criteria applied to define the specific condition / phenotype represented in the case (exposed) group
- Partcipants diagnosed with Non-alcoholic fatty liver disease (now known as Metabolic dysfunction-associated fatty liver disease "MAFLD")
- Group 0 sample size Number of subjects in the control (unexposed) group
- 20
- Group 1 sample size Number of subjects in the case (exposed) group
- 21
- Antibiotics exclusion Number of days without antibiotics usage (if applicable) and other antibiotics-related criteria used to exclude participants (if any)
- 6 months
Lab analysis
- Sequencing type
- WMS
- 16S variable region One or more hypervariable region(s) of the bacterial 16S gene
- Not specified
- Sequencing platform Manufacturer and experimental platform used for quantifying microbial abundance
- Illumina
Statistical Analysis
- Data transformation Data transformation applied to microbial abundance measurements prior to differential abundance testing (if any).
- relative abundances
- Statistical test
- LEfSe
- Significance threshold p-value or FDR threshold used for differential abundance testing (if any)
- 0.05
- MHT correction Have statistical tests be corrected for multiple hypothesis testing (MHT)?
- No
- LDA Score above Threshold for the linear discriminant analysis (LDA) score for studies using the popular LEfSe tool
- 2.0
- Matched on Factors on which subjects have been matched on in a case-control study
- age, sex
Alpha Diversity
- Shannon Estimator of species richness and species evenness: more weight on species richness
- unchanged
- Chao1 Abundance-based estimator of species richness
- increased
- Simpson Estimator of species richness and species evenness: more weight on species evenness
- unchanged
Experiment 2
Differences from previous experiment shown
Lab analysis
Statistical Analysis
- Statistical test
- Kruskall-Wallis
- Confounders controlled for Confounding factors that have been accounted for by stratification or model adjustment
- age, sex
Alpha Diversity
- Shannon Estimator of species richness and species evenness: more weight on species richness
- unchanged
- Chao1 Abundance-based estimator of species richness
- increased
- Simpson Estimator of species richness and species evenness: more weight on species evenness
- unchanged
Experiment 3
Differences from previous experiment shown
Subjects
- Body site Anatomical site where microbial samples were extracted from according to the Uber Anatomy Ontology
- Feces Cow dung,Cow pat,Droppings,Dung,Excrement,Excreta,Faeces,Fecal material,Fecal matter,Fewmet,Frass,Guano,Matières fécales@fr,Merde@fr,Ordure,Partie de la merde@fr,Piece of shit,Porción de mierda@es,Portion of dung,Portion of excrement,Portion of faeces,Portion of fecal material,Portion of fecal matter,Portion of feces,Portion of guano,Portion of scat,Portionem cacas,Scat,Spoor,Spraint,Stool,Teil der fäkalien@de,Feces,feces
Lab analysis
Statistical Analysis
Alpha Diversity
- Shannon Estimator of species richness and species evenness: more weight on species richness
- decreased
- Simpson Estimator of species richness and species evenness: more weight on species evenness
- decreased