Interactions of Segmented Filamentous Bacteria (Candidatus Savagella) and bacterial drivers in colitis-associated colorectal cancer development

Sex differences in colorectal cancer: with a focus on sex hormone-gut microbiome axis

Sexual dimorphism has been observed in the incidence and prognosis of colorectal cancer (CRC), with men generally exhibiting a slightly higher incidence than women. Research suggests that this difference may be attributed to variations in sex steroid hormone levels and the gut microbiome. The gut microbiome in CRC shows variations in composition and function between the sexes, leading to the concept of 'microgenderome' and 'sex hormone-gut microbiome axis.' Conventional research indicates that estrogens, by promoting a more favorable gut microbiota, may reduce the risk of CRC. Conversely, androgens may have a direct pro-tumorigenic effect by increasing the proportion of opportunistic pathogens. The gut microbiota may also influence sex hormone levels by expressing specific enzymes or directly affecting gonadal function. However, this area remains controversial. This review aims to explore the differences in sex hormone in CRC incidence, the phenomenon of sexual dimorphism within the gut microbiome, and the intricate interplay of the sex hormone-gut microbiome axis in CRC. The objective is to gain a better understanding of these interactions and their potential clinical implications, as well as to introduce innovative approaches to CRC treatment.

Identification of commensal gut microbiota signatures as predictors of clinical severity and disease progression in multiple sclerosis

Background

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system and a leading cause of neurological disability in young adults. Clinical presentation and disease course are highly heterogeneous. Typically, disease progression occurs over time and is characterized by the gradual accumulation of disability. The risk of developing MS is driven by complex interactions between genetic and environmental factors, including the gut microbiome. How the commensal gut microbiota impacts disease severity and progression over time remains unknown.

Methods

In a longitudinal study, disability status and associated clinical features in 60 MS patients were tracked over 4.2 ± 0.97 years, and the baseline fecal gut microbiome was characterized via 16S amplicon sequencing. Progressor status, defined as patients with an increase in Expanded Disability Status Scale (EDSS), were correlated with features of the gut microbiome to determine candidate microbiota associated with risk of MS disease progression.

Results

We found no overt differences in microbial community diversity and overall structure between MS patients exhibiting disease progression and non-progressors. However, a total of 45 bacterial species were associated with worsening disease, including a marked depletion in Akkermansia , Lachnospiraceae, and Oscillospiraceae , with an expansion of Alloprevotella , Prevotella-9 , and Rhodospirillales . Analysis of the metabolic potential of the inferred metagenome from taxa associated with progression revealed a significant enrichment in oxidative stress-inducing aerobic respiration at the expense of microbial vitamin K ₂ production (linked to Akkermansia ), and a depletion in SCFA metabolism (linked to Lachnospiraceae and Oscillospiraceae ). Further, statistical modeling demonstrated that microbiota composition and clinical features were sufficient to robustly predict disease progression. Additionally, we found that constipation, a frequent gastrointestinal comorbidity among MS patients, exhibited a divergent microbial signature compared with progressor status.

Conclusions

These results demonstrate the utility of the gut microbiome for predicting disease progression in MS. Further, analysis of the inferred metagenome revealed that oxidative stress, vitamin K ₂ and SCFAs are associated with progression.

Abstract Figure

Modulatory Effect of Fermented Black Soybean and Adlay on Gut Microbiota Contributes to Healthy Aging

SCOPE

Aging is a natural process characterized by a multifactorial, physical decline, and functional disability. Nevertheless, healthy aging can be achieved by following a multidirectional strategy. The current study aims to investigate the anti-aging potential of fermented black soybean and adlay (FBA).

METHODS AND RESULTS

FBA supplements are incorporated into a natural aging mouse model that is designed to evaluate anti-aging effects. Results show that FBA supplementation prevents muscle loss and visceral adipose tissue accumulation. FBA can also reduce aging biomarkers (including the expression of hepatic p16^INK4A and galactosidase beta-1 (GLB1). Hepatic 8-hydoxy-2'-deoxyguanosine (8-oxodG) and pro-inflammatory cytokines have been significantly reduced. Lastly, FBA supplementation improves aging-related gut microbial dysbiosis by reshaping gut microbial composition and promoting the growth of beneficial microbes such as Alistipes, Anaeroplasma, Coriobacteriaceae UCG002, and Parvibacter members in both genders of aged mice. In the functional prediction of gut microbiota, correlations to metabolic, neurodegenerative, infectious, and immune system diseases have been reduced in supplemented mice compared to aged mice. Moreover, FBA supplementation can reverse the reduced ability of microbiota in aged mice for lipid metabolism and xenobiotics biodegradation.

CONCLUSIONS

The results suggest that FBA exhibits noteworthy anti-aging effects and that it can potentially be developed into a functional food for healthy aging.

The gut microbiome of laboratory mice: considerations and best practices for translational research

Just as the gut microbiota (GM) is now recognized as an integral mediator of environmental influences on human physiology, susceptibility to disease, and response to pharmacological intervention, so too does the GM of laboratory mice affect the phenotype of research using mouse models. Multiple experimental factors have been shown to affect the composition of the GM in research mice, as well as the model phenotype, suggesting that the GM represents a major component in experimental reproducibility. Moreover, several recent studies suggest that manipulation of the GM of laboratory mice can substantially improve the predictive power or translatability of data generated in mouse models to the human conditions under investigation. This review provides readers with information related to these various factors and practices, and recommendations regarding methods by which issues with poor reproducibility or translatability can be transformed into discoveries.