Akkermansia muciniphila is a promising probiotic

Akkermansia muciniphila: A promising probiotic against inflammation and metabolic disorders

Metabolic disease is a worldwide epidemic that has become a public health problem. Gut microbiota is considered to be one of the important factors that maintain human health by regulating host metabolism. As an abundant bacterium in the host gut, A. muciniphila regulates metabolic and immune functions, and protects gut health. Multiple studies have indicated that alterations in the abundance of A. muciniphila are associated with various diseases, including intestinal inflammatory diseases, obesity, type 2 diabetes mellitus, and even parasitic diseases. Beneficial effects were observed not only in live A. muciniphila, but also in pasteurized A. muciniphila, A. muciniphila-derived extracellular vesicles, outer membrane, and secreted proteins. Although numerous studies have only proven the simple correlation between multiple diseases and A. muciniphila, an increasing number of studies in animal models and preclinical models have demonstrated that the beneficial impacts shifted from correlations to in-depth mechanisms. In this review, we provide a comprehensive view of the beneficial effects of A. muciniphila on different diseases and summarize the potential mechanisms of action of A. muciniphila in the treatment of diseases. We provide a comprehensive understanding of A. muciniphila for improving host health and discuss the perspectives of A. muciniphila in the future studies.

Traditional medicine Xianglian pill suppresses high-fat diet-related colorectal cancer via inactivating TLR4/MyD88 by remodeling gut microbiota composition and bile acid metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Previous studies have revealed that a high-fat diet (HFD) promotes the progression of colorectal cancer (CRC) in close association with disturbances in the intestinal flora and metabolic disorders. Xianglian pill (XLP) is a well-established traditional prescription with unique advantages in controlling intestinal flora imbalance and inflammation. However, its therapeutic effects on HFD-related CRC remain largely unknown.

AIM OF THE STUDY

The primary objective of this research was to investigate the anticancer mechanism of XLP in countering HFD-related CRC.

MATERIALS AND METHODS

The protective effect of XLP was evaluated using azoxymethane (AOM) and dextran sulfate sodium (DSS)-induced CRC model of mice exposed to a HFD. The degree of colorectal carcinogenesis, including body weight, colon length, and histopathology, was measured in mice treated with XLP and untreated mice. The effect of XLP on gut microbiota and its metabolites was detected using 16S rDNA and liquid chromatography/mass spectrometry analysis. Furthermore, a "pseudo-sterile" mouse model was constructed using antibiotics (Abx) to verify whether the gut microbiota and metabolites play a role in the pathogenesis of CRC.

RESULTS

XLP inhibited colorectal tumorigenesis in a dose-dependent fashion. Our findings also highlighted that XLP protected the integrity of the intestinal barrier by reducing the expression of pro-inflammatory cytokines, such as IL-6 and TNF-α, as well as the infiltration of pro-inflammatory macrophages. Mechanistically, XLP inhibited the TLR4/MyD88 pathway. Notably, the XLP treatment increased the proportion of probiotics (particularly Akkermansia) and significantly reduced fecal deoxycholic acid (DCA), a microbiota-derived metabolite of bile acids (BA) closely related to Muribaculaceae. Furthermore, after Abx treatment, XLP showed no clear antitumor effects on CRC. Simultaneously, DCA-supplemented feedings promoted colorectal tumorigenesis and provoked obvious colonic inflammation, M1 macrophage infiltration, and colonic injury. In vitro, the results of RAW-264.7 macrophages and normal intestinal epithelial cells treated with DCA corroborated our in vivo findings, demonstrating consistent patterns in inflammatory responses and intestinal barrier protein expression.

CONCLUSION

Our findings suggest that XLP inhibits colorectal cancer associated with HFD via inactivating TLR4/MyD88 by remodeling gut microbiota composition and BA metabolism.

Chinese expert consensus on standard technical specifications for a gut microecomics laboratory (Review)

The intestinal microbiota is a complex ecosystem that not only affects various physiological functions, such as metabolism, inflammation and the immune response, but also has an important effect on the development of tumors and response to treatment. The detection of intestinal flora enables the timely identification of disease-related flora abnormalities, which has significant implications for both disease prevention and treatment. In the field of basic and clinical research targeting gut microbiome, there is a need to recognize and understand the laboratory assays for gut microbiomics. Currently, there is no unified standard for the experimental procedure, quality management and report interpretation of intestinal microbiome assay technology. In order to clarify the process, the Tumor and Microecology Committee of China Anti-Cancer Association and the Tumor and Microecology Committee of Hubei Provincial Immunology Society organized relevant experts to discuss and put forward the standard technical specifications for gut microecomics laboratories, which provides a basis for further in-depth research in the field of intestinal microecomics.

Exploring the efficacy and mechanism of Bailing capsule to improve polycystic ovary syndrome in mice based on intestinal-derived LPS-TLR4 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Polycystic ovary syndrome (PCOS) is a common endocrine disorder associated with reproductive dysfunction and metabolic abnormalities, particularly characterized by insulin resistance and chronic low-grade inflammation. Multiple clinical studies have clearly demonstrated the significant efficacy and safety of the combination of Bailing capsules (BL) in the treatment of PCOS, but its pharmacological effects and mechanisms still require further study.

AIM OF THE STUDY

To evaluate the effect of BL on improving PCOS in mice and explore the mechanism.

METHODS

In this study, Dehydroepiandrosterone (DHEA) injection was administered alone and in combination with a high-fat and high-sugar diet to induce PCOS-like mouse. They were randomly divided into five groups: normal group (N), PCOS group (P), Bailing capsule low-dose group (BL-L), Bailing capsule high-dose group (BL-H) and Metformin + Daine-35 group (M + D). Firstly, the effects of BL on ovarian lesions, serum hormone levels, HOMA-IR, intestinal barrier function, inflammation levels, along with the expression of IRS1, PI3K, AKT, TLR4, Myd88, NF-κB p65, TNF-α, IL-6, and Occludin of the ovary, liver and colon were investigated. Finally, the composition of the gut microbiome of fecal was tested.

RESULTS

The administration of BL significantly reduced body weight, improved hormone levels, improved IR, and attenuated pathological damage to ovarian tissues, up-regulated the expression of IRS1, PI3K, and AKT in liver. It also decreased serum LPS, TNF-α, and IL-6 levels, while downregulating the expression of Myd88, TLR4, and NF-κB p65. Additionally, BL improved intestinal barrier damage and upregulated the expression of Occludin. Interestingly, the abundance of norank_f__Muribaculacea and Lactobacillus was down-regulated, while the abundance of Akkermansia was significantly up-regulated.

CONCLUSION

The results of the study showed that BL exerts a treatment PCOS effect, which may be related to the modulation of the gut microbiota, the improvement of insulin resistance and the intestinal-derived LPS-TLR4 inflammatory pathway. Our research will provide a theoretical basis for the clinical treatment of PCOS.

Preeclampsia: A comprehensive review

Preeclampsia (PE) is a life-threatening disease of pregnancy and a prominent cause of neonatal and maternal mortality and morbidity. PE affects approximately 5-10% of pregnancies worldwide, posing significant risks to perinatal and maternal health. It is characterized by a variety of interconnected pathological cascades contributing to the stimulation of intravascular inflammation, oxidative stress (OS), endothelial cell activation, and syncytiotrophoblast stress that converge on a common pathway, ultimately resulting in disease progression. The present study was designed and executed to review the existing scientific literature, specifically focusing on the etiology (gestational diabetes mellitus and maternal obesity, insulin resistance, metabolic syndrome, maternal infection, periodontal disease, altered microbiome, and genetics), clinical presentations (hypertension, blood disorders, proteinuria, hepatic dysfunction, renal dysfunction, pulmonary edema, cardiac dysfunction, fetal growth restrictions, and eclampsia), therapeutic clinical biomarkers (creatinine, albuminuria, and cystatin C) along with their associations and mechanisms in PE. In addition, this study provides insights into the potential of nanomedicines for targeting these mechanisms for PE management and treatment. Inflammation, OS, proteinuria, and an altered microbiome are prominent biomarkers associated with progression and PE-related pathogenesis. Understanding the molecular mechanisms, exploring suitable markers, targeted interventions, comprehensive screening, and holistic strategies are critical to decreasing the incidence of PE and promoting maternal-fetal well-being. The present study comprehensively reviewed the etiology, clinical presentations, therapeutic biomarkers, and preventive potential of nanomedicines in the treatment and management of PE.

Immune and microbiome modulatory effects of Limosilactobacillus fermentum NCDC 400 in an immunocompromised mouse model

The present study was aimed to assess and validate the safety and functional efficacy of an indigenous probiotic strain Limosilactobacillus fermentum NCDC 400 (hereafter, LFN400) in an immunocompromised murine model. The study included four groups; a normal control (NC) group without immune suppression; an experimental model control (MC) with immune suppression induced via intraperitoneal cyclophosphamide (Cy) administration; and two MC groups orally administered with either low dose (LD) or high dose (HD) of LFN400 at dose 108 and 1010 CFU/mouse/day, respectively, for 15-days. Both control groups received normal saline as placebo control. LFN400 improved specific experimental characteristics including hematological and serum biochemical markers. Compared to MC group, LFN400-fed groups showed markedly (P < 0.05) decreased arrays of detrimental caecal enzymes. We did not observe instances of bacterial translocation of LFN400 from gut to bloodstream or extra-intestinal organs. LFN400 intake significantly (P < 0.05) enhanced spleen cell differentiation, immune and oxidative stress markers, and restored Cy-induced histopathological changes in multiple tissues, including the spleen. There was no genotoxic effect of LFN400 on bone marrow cells. Although not statistically significant, LFN400 feeding moderately increased gut microbiome diversity, supporting the growth of beneficial saccharolytic microorganisms and reducing the presence of pathobionts. The findings demonstrate that the probiotic strain LFN400 possesses in vivo safety and immunomodulatory potency and thus should be considered a potential candidate for future human clinical studies.

The human microbiome in space: parallels between Earth-based dysbiosis, implications for long-duration spaceflight, and possible mitigation strategies

SUMMARYThe human microbiota encompasses the diverse communities of microorganisms that reside in, on, and around various parts of the human body, such as the skin, nasal passages, and gastrointestinal tract. Although research is ongoing, it is well established that the microbiota exert a substantial influence on the body through the production and modification of metabolites and small molecules. Disruptions in the composition of the microbiota-dysbiosis-have also been linked to various negative health outcomes. As humans embark upon longer-duration space missions, it is important to understand how the conditions of space travel impact the microbiota and, consequently, astronaut health. This article will first characterize the main taxa of the human gut microbiota and their associated metabolites, before discussing potential dysbiosis and negative health consequences. It will also detail the microbial changes observed in astronauts during spaceflight, focusing on gut microbiota composition and pathogenic virulence and survival. Analysis will then turn to how astronaut health may be protected from adverse microbial changes via diet, exercise, and antibiotics before concluding with a discussion of the microbiota of spacecraft and microbial culturing methods in space. The implications of this review are critical, particularly with NASA's ongoing implementation of the Moon to Mars Architecture, which will include weeks or months of living in space and new habitats.

Bacterial interactions on nutrient-rich surfaces in the gut lumen

The intestinal lumen is a turbulent, semi-fluid landscape where microbial cells and nutrient-rich particles are distributed with high heterogeneity. Major questions regarding the basic physical structure of this dynamic microbial ecosystem remain unanswered. Most gut microbes are non-motile, and it is unclear how they achieve optimum localization relative to concentrated aggregations of dietary glycans that serve as their primary source of energy. In addition, a random spatial arrangement of cells in this environment is predicted to limit sustained interactions that drive co-evolution of microbial genomes. The ecological consequences of random versus organized microbial localization have the potential to control both the metabolic outputs of the microbiota and the propensity for enteric pathogens to participate in proximity-dependent microbial interactions. Here, we review evidence suggesting that several bacterial species adopt organized spatial arrangements in the gut via adhesion. We highlight examples where localization could contribute to antagonism or metabolic interdependency in nutrient degradation, and we discuss imaging- and sequencing-based technologies that have been used to assess the spatial positions of cells within complex microbial communities.

Gut microbiota and risk of ankylosing spondylitis

OBJECTIVE

Observational studies have established a connection between gut microbiota and ankylosing spondylitis (AS) risk; however, whether the observed associations are causal remains unclear. Therefore, we conducted a two-sample Mendelian randomization (MR) analysis to assess the potential causal associations of gut microbiota with AS risk.

METHODS

Instrumental variants of gut microbiota were obtained from the MiBioGen consortium (n = 18,340) and the Dutch Microbiome Project (n = 7738). The FinnGen consortium provided genetic association summary statistics for AS, encompassing 2860 cases and 270,964 controls. We used the inverse-variance weighted (IVW) method as the primary analysis, supplemented with the weighted median method, maximum likelihood-based method, MR pleiotropy residual sum and outlier test, and MR-Egger regression. In addition, we conducted a reverse MR analysis to assess the likelihood of reverse causality.

RESULTS

After the Bonferroni correction, species Bacteroides vulgatus remained statistically significantly associated with AS risk (odds ratio (OR) 1.55, 95% confidence interval (CI) 1.22-1.95, P = 2.55 × 10-4). Suggestive evidence of associations of eleven bacterial traits with AS risk was also observed (P < 0.05 by IVW). Among them, eight were associated with an elevated AS risk (OR 1.37, 95% CI 1.07-1.74, P = 0.011 for phylum Verrucomicrobia; OR 1.31, 95% CI 1.03-1.65, P = 0.026 for class Verrucomicrobiae; OR 1.17, 95% CI 1.01-1.36, P = 0.035 for order Bacillales; OR 1.31, 95% CI 1.03-1.65, P = 0.026 for order Verrucomicrobiales; OR 1.43, 95% CI 1.13-1.82, P = 0.003 for family Alcaligenaceae; OR 1.31, 95% CI 1.03-1.65, P = 0.026 for family Verrucomicrobiaceae; OR 1.31, 95% CI 1.03-1.65, P = 0.026 for genus Akkermansia; OR 1.55, 95% CI 1.19-2.02, P = 0.001 for species Sutterella wadsworthensis). Three traits exhibited a negative association with AS risk (OR 0.68, 95% CI 0.53-0.88, P = 0.003 for genus Dialister; OR 0.84, 95% CI 0.72-0.97, P = 0.020 for genus Howardella; OR 0.75, 95% CI 0.59-0.97, P = 0.026 for genus Oscillospira). Consistent associations were observed when employing alternate MR methods. In the reverse MR, no statistically significant correlations were detected between AS and these bacterial traits.

CONCLUSION

Our results revealed the associations of several gut bacterial traits with AS risk, suggesting a potential causal role of gut microbiota in AS development. Nevertheless, additional research is required to clarify the mechanisms by which these bacteria influence AS risk. Key Points • The association of gut microbiota with AS risk in observational studies is unclear. • This MR analysis revealed associations of 12 gut bacterial traits with AS risk.

Novel pectin-carboxymethylcellulose-based double-layered mucin/chitosan microcomposites successfully protect the next-generation probiotic Akkermansia muciniphila through simulated gastrointestinal transit and alters microbial communities within colonic ex vivo bioreactors

The rapid acceleration of microbiome research has identified many potential Next Generation Probiotics (NGPs). Conventional formulation processing methods are non-compatible, leading to reduced viability and unconfirmed incorporation into intestinal microbial communities; consequently, demand for more bespoke formulation strategies of such NGPs is apparent. In this study, Akkermansia muciniphila (A.muciniphila) as a candidate NGP was investigated for its growth and metabolism properties, based on which a novel microcomposite-based oral formulation has been formed. Initially, a chitosan-based microcomposite is coated with mucin to establish surface culture of A.muciniphila. This was followed by 'double encapsulation' with pectin (PEC) using a novel Entrapment Deposition by Prilling method to create core-shell double-encapsulated microcapsules. The formulation of A.muciniphila was verified to require no oxygen-restriction properties, and additionally, biopolymers were selected (including carboxymethylcellulose (CMC)) that support and enhance its growth; consequently, a high viability (6 log CFU/g) of A.muciniphila microencapsulated in PEC-CMC double-encapsulates was obtained. Subsequently, the high stability of the PEC-CMC double-encapsulates was verified in simulated gastric fluid, successfully protecting and then releasing the A.muciniphila within intestinal conditions. Finally, employing a model of gastrointestinal transit and faecal-inoculated colonic bioreactors, significant alterations in microbial communities following administration and successful establishment of A.muciniphila were demonstrated.

Inhibition of FoxO1 ameliorates hepatic steatosis and hepatitis in nonalcoholic steatohepatitis mice through regulation of gut microbiota

OBJECTIVE

We aimed to investigate the role of forkhead box O1 (FoxO1) inhibitor AS1842856 (AS) in nonalcoholic steatohepatitis (NASH) mice and the potential mechanisms.

METHODS

Mice were given methionine-choline-sufficient (MCS), or methionine- and choline-deficient (MCD) diet for 5 weeks, along with AS (60 mg/kg) or vehicle gavage treatment (0.2 mL/day). Body and liver weight, serum triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), alanine aminotransferase (ALT), aspartate aminotransferase (AST), fasting glucose and insulin levels were measured. Liver macrophage infiltration and ileal ZO-1 protein expression were also detected. Interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α, sterol regulatory element binding protein (SREBP)-1c, phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (G6Pase), α-smooth muscle actin (SMA), recombinant collagen type III α1 (Col3a1), and connective tissue growth factor (Ctgf) expressions were measured. Stool samples were collected for 16S rDNA sequencing.

RESULTS

Compared to the MCD group, AS attenuated liver weight, reduced serum TG, ALT, and AST levels, increased HDL-C levels, mitigated hepatic steatosis, decreased macrophage infiltration, and augmented ileal ZO-1 proteins in NASH mice. It also reduced the levels of IL-6, IL-1β, and TNF-α, alongside with the Srebp-1c mRNA expression. However, no significant effects on Pepck, G6Pase, α-SMA, Col3a1, or Ctgf were observed. Furthermore, AS promoted diversity and altered gut microbiota composition in NASH mice, causing increased beneficial bacteria like Akkermansia muciniphila, Parabacteroides distasonis, and Prevotellamassilia, which were associated with metabolic functions.

CONCLUSION

FoxO1 inhibitor AS ameliorated hepatic steatosis, inflammation, and intestinal dysbiosis in NASH mice, making it a potentially promising treatment for NASH.

Difference in gut microbial dysbiotic patterns between body-first and brain-first Parkinson's disease

BACKGROUND

This study aims to identify distinct microbial and functional biomarkers characteristic of body-first or brain-first subtypes of Parkinson's disease (PD). This could illuminate the unique pathogenic mechanisms within these subtypes.

METHODS

In this cross-sectional study, we classified 36 well-characterized PD patients into body-first, brain-first, or undetermined subtypes based on the presence of premotor REM sleep behavior disorder (RBD) and cardiac meta-iodobenzylguanidine (MIBG) uptake. We then conducted an in-depth shotgun metagenomic analysis of the gut microbiome for each subtype and compared the results with those from age- and sex-matched healthy controls.

RESULTS

Significant differences were found in the gut microbiome of body-first PD patients (n = 15) compared to both brain-first PD patients (n = 9) and healthy controls. The gut microbiome in body-first PD showed a distinct profile, characterized by an increased presence of Escherichia coli and Akkermansia muciniphila, and a decreased abundance of short-chain fatty acid-producing commensal bacteria. These shifts were accompanied by a higher abundance of microbial genes associated with curli protein biosynthesis and a lower abundance of genes involved in putrescine and spermidine biosynthesis. Furthermore, the combined use of premotor RBD and MIBG criteria was more strongly correlated with these microbiome differences than the use of each criterion independently.

CONCLUSIONS

Our findings highlight the significant role of dysbiotic and pathogenic gut microbial alterations in body-first PD, supporting the body-first versus brain-first hypothesis. These insights not only reinforce the gut microbiome's potential as a therapeutic target in PD but also suggest the possibility of developing subtype-specific treatment strategies.

Metabolomics combined with intestinal microbiota reveals the mechanism of compound Qilian tablets against diabetic retinopathy

Background

Diabetic retinopathy (DR) is one of the common chronic complications of diabetes mellitus, which has developed into the leading cause of irreversible visual impairment in adults worldwide. Compound Qilian tablets (CQLT) is a traditional Chinese medicine (TCM) developed for treating DR, but its mechanism is still unclear. This study explored the mechanism of action of CQLT in treating DR through metabolomics and intestinal microbiota.

Methods

Histopathologic examination of the pancreas and retina of Zucker diabetic fatty (ZDF) rats and immunohistochemistry were used to determine the expression levels of retinal nerve damage indicators ionized calcium binding adaptor molecule-1 (Iba-1) and glial fibrillary acidic protein (GFAP). Rat fecal samples were tested by LC-MS metabolomics to search for potential biomarkers and metabolic pathways for CQLT treatment of DR. Characteristic nucleic acid sequences of rat intestinal microbiota from each group were revealed using 16S rDNA technology to explore key microbes and related pathways for CQLT treatment of DR. At the same time, we investigated the effect of CQLT on the gluconeogenic pathway.

Results

After CQLT intervention, islet cell status was improved, Iba-1 and GFAP expression were significantly decreased, and abnormal retinal microvascular proliferation and exudation were ameliorated. Metabolomics results showed that CQLT reversed 20 differential metabolites that were abnormally altered in DR rats. Intestinal microbiota analysis showed that treatment with CQLT improved the abundance and diversity of intestinal flora. Functional annotation of metabolites and intestinal flora revealed that glycolysis/gluconeogenesis, alanine, aspartate and glutamate metabolism, starch and sucrose metabolism were the main pathways for CQLT in treating DR. According to the results of correlation analysis, there were significant correlations between Iba-1, GFAP, and intestinal microbiota and metabolites affected by CQLT. In addition, we found that CQLT effectively inhibited the gluconeogenesis process in diabetic mice.

Conclusion

In conclusion, CQLT could potentially reshape intestinal microbiota composition and regulate metabolite profiles to protect retinal morphology and function, thereby ameliorating the progression of DR.

Alterations in gut microbiota and inflammatory cytokines after administration of antibiotics in mice

Antibiotics are widely used to treat bacterial infection and reduce the mortality rate, while antibiotic overuse can cause gut microbiota dysbiosis. The impact of antibiotics on gut microbiota is not fully understood. In our study, four commonly used antibiotics (ceftazidime, cefoperazone-sulbactam, imipenem-cilastatin, and moxifloxacin) were given subcutaneously to mice, and their impacts on the gut microbiota composition and serum cytokine levels were evaluated through 16S rRNA analysis and a multiplex immunoassay. Antibiotic treatment markedly reduced gut microbiota diversity and changed gut microbiota composition. Antibiotic treatment significantly increased and decreased the abundance of Firmicutes and Bacteroidota, respectively. The antibiotic treatments increased the abundance of opportunistic pathogens such as Enterococcus and decreased that of Lachnospiraceae and Muribaculaceae. For moxifloxacin, the significantly high abundance of Enterococcus and Klebsiella was observed after 14 and 21 days of treatment. However, a relatively low abundance of opportunistic pathogens was found after 14 days of imipenem-cilastatin treatment. Additionally, the serum levels of various pro-inflammatory cytokines, such as IL-1β, IL-12 (p70), and IL-17, significantly increased after 21 days of antibiotic treatments. Overall, these results provide a guide for rational use of antibiotics in clinical settings: short-term use of moxifloxacin is recommended with regard to gut microbiota health, and the 14-day use of imipenem-cilastatin may have a less severe impact than other antibiotics.IMPORTANCEAntibiotic treatments are directly associated with changes in gut microbiota and are effective against both pathogens and beneficial bacteria. Gut microbiota dysbiosis induced by antibiotic treatment could increase the risk of some diseases. Therefore, an adequate understanding of gut microbiota changes after antibiotic use is crucial. In this study, we investigated the effects of continuous treatment with antibiotics on gut microbiota, serum cytokines, and intestinal inflammatory response. Our results suggest that short-term use of moxifloxacin is recommended, and the 14-day use of imipenem-cilastatin may have a less severe effect on gut microbiota health than cefoperazone-sulbactam. These results provide useful guidance on the rational use of antibiotics with regard to gut microbiota health.

Duck gut metagenome reveals the microbiome signatures linked to intestinal regional, temporal development, and rearing condition

The duck gastrointestinal tract (GIT) harbors an abundance of microorganisms that play an important role in duck health and production. Here, we constructed the first relatively comprehensive duck gut microbial gene catalog (24 million genes) and 4437 metagenome-assembled genomes using 375 GIT metagenomic samples from four different duck breeds across five intestinal segments under two distinct rearing conditions. We further characterized the intestinal region-specific microbial taxonomy and their assigned functions, as well as the temporal development and maturation of the duck gut microbiome. Our metagenomic analysis revealed the similarity within the microbiota of the foregut and hindgut compartments, but distinctive taxonomic and functional differences between distinct intestinal segments. In addition, we found a significant shift in the microbiota composition of newly hatched ducks (3 days), followed by increased diversity and enhanced stability across growth stages (14, 42, and 70 days), indicating that the intestinal microbiota develops into a relatively mature and stable community as the host duck matures. Comparing the impact of different rearing conditions (with and without water) on duck cecal microbiota communities and functions, we found that the bacterial capacity for lipopolysaccharide biosynthesis was significantly increased in ducks that had free access to water, leading to the accumulation of pathogenic bacteria and antibiotic-resistance genes. Taken together, our findings expand the understanding of the microbiome signatures linked to intestinal regional, temporal development, and rearing conditions in ducks, which highlight the significant impact of microbiota on poultry health and production.

A Critical Review on Akkermansia muciniphila: Functional Mechanisms, Technological Challenges, and Safety Issues

Due to its physiological benefits from in vitro and in vivo points of view, Akkermansia muciniphila, a common colonizer in the human gut mucous layer, has consistently been identified as an option for the next-generation probiotic. A. muciniphila is a significant bacterium that promotes host physiology. However, it also has a great deal of potential to become a probiotic due to its physiological advantages in a variety of therapeutic circumstances. Therefore, it can be established that the abundance of A. muciniphila in the gut environment, which is controlled by many genetic and dietary variables, is related to the biological behaviors of the intestinal microbiota and gut dysbiosis/eubiosis circumstances. Before A. muciniphila is widely utilized as a next-generation probiotic, regulatory obstacles, the necessity for significant clinical trials, and the sustainability of manufacturing must be eliminated. In this review, the outcomes of recent experimental and clinical reports are comprehensively reviewed, and common colonization patterns, main factors involved in the colonization of A. muciniphila in the gut milieu, their functional mechanisms in establishing homeostasis in the metabolic and energy pathways, the promising delivery role of microencapsulation, potential genetic engineering strategies, and eventually safety issues of A. muciniphila have been discussed.

Causal associations among gut microbiota, 1400 plasma metabolites, and asthma: a two-sample Mendelian randomization study

Background

Emerging evidence indicates a correlation between imbalances in intestinal microbiota and changes in plasma metabolites in the progression of asthma. However, the causal link between these factors remains unclear.

Methods

A two-sample Mendelian randomization (MR) study was employed to evaluate the potential causal connection between gut microbiota, plasma metabolites, and asthma susceptibility. Gut microbiota data from expansive genome-wide genotype studies and 16S fecal microbiome datasets were examined by the MiBioGen Alliance. Asthma data were procured from the FinnGen biobank analysis, while comprehensive Genome-Wide Association Studies (GWAS) summary statistics for plasma metabolites were derived from the NHGRI-EBI GWAS Catalog. Fluctuations in intestinal flora and plasma metabolites in asthma patients were evaluated using the weighted mode method. Additionally, pleiotropic and heterogeneity analyses were performed to ascertain the reliability of the findings.

Results

Upon examining the gut microbiota through MR with the IVW method, alongside tests for heterogeneity and pleiotropy, findings reveal a negative association between the abundance of the Christensenellaceae R.7 group and asthma risk. In contrast, the Bifidobacterium and Prevotella 7 genera exhibit a positive association with asthma risk, indicating they may be potential risk factors (p < 0.05). Furthermore, MR analysis of 1,400 metabolites employing Weighted median, IVW, and Weighted mode methods resulted in p-values below 0.05. Subsequent tests for pleiotropy and heterogeneity showed that the levels of 3,5-dichloro-2,6-dihydroxybenzoic acid have a negative correlation with asthma, whereas the phenylalanine to phosphate ratio has a positive correlation, suggesting their potential as risk factors for asthma (p < 0.05).

Conclusion

The current Mendelian randomization study provides evidence supporting a potential causal link between specific gut microbiota taxa, plasma metabolites, and asthma. These findings offer novel perspectives for future research and the development of treatment and prevention strategies for asthma.

Monoacylglycerol acyltransferase-2 inhibits colorectal carcinogenesis in APCmin+/- mice

Monoacylglycerol acyltransferase-2 (MOGAT2), encodes MOGAT enzyme in the re-synthesis of triacylglycerol and protects from metabolism disorders. While, its precise involvement in colorectal cancer (CRC) progression remains inadequately understood. Our study demonstrated that knockout of Mogat2 in Apcmin/+ mice expedited intestinal tumor growth and progression, indicating that Mogat2 plays a tumor-suppressing role in CRC. Mechanically, Mogat2 deletion resulted in a significant alter the gut microbiota, while Fecal Microbiota Transplantation (FMT) experiments demonstrated that the gut microbiota in Mogat2 deleted mice promoted tumor growth. Furthermore, we identified Mogat2 as a functional regulator suppressing CRC cell proliferation and tumor growth by inhibiting the NF-κB signaling pathway in vivo. Collectively, these results provide novel insights into the protective double roles of Mogat2, inhibiting of NF-κB pathway and keeping gut microbiota homeostasis in colorectal cancer, which may help the development of novel cancer treatments for CRC.

Gut microbiota-derived metabolites tune host homeostasis fate

The gut microbiota, housing trillions of microorganisms within the gastrointestinal tract, has emerged as a critical regulator of host health and homeostasis. Through complex metabolic interactions, these microorganisms produce a diverse range of metabolites that substantially impact various physiological processes within the host. This review aims to delve into the intricate relationships of gut microbiota-derived metabolites and their influence on the host homeostasis. We will explore how these metabolites affect crucial aspects of host physiology, including metabolism, mucosal integrity, and communication among gut tissues. Moreover, we will spotlight the potential therapeutic applications of targeting these metabolites to restore and sustain host equilibrium. Understanding the intricate interplay between gut microbiota and their metabolites is crucial for developing innovative strategies to promote wellbeing and improve outcomes of chronic diseases.

Taste Preferences at Different Ambient Temperatures and Associated Changes in Gut Microbiota and Body Weight in Mice

Taste, dietary choices, and gut microbiota are often analyzed as major factors of metabolic health. Populations living in cold or hot regions have different dietary habits. This study aims to investigate the potential association among ambient temperature, food taste preferences, and cecal microbiota community profiles in mice. By exposing mice to mixed diets containing sweet, sour, salty, and bitter flavors at low (4 °C) and high (37 °C) ambient temperatures, the taste preferences of mice at both ambient temperatures were in the order of saltiness > sweetness > bitterness > sourness. Exposing mice to sweet, sour, salty, and bitter diets, respectively, revealed that in a low-temperature environment, mice consuming salty (5.00 ± 1.49 g), sweet (4.99 ± 0.35 g), and sour (3.90 ± 0.61 g) diets had significantly higher weight gain compared to those consuming normal feeds (2.34 ± 0.43 g, p < 0.05). Conversely, in a high-temperature environment, no significant changes in body weight were observed among mice consuming different flavored diets (p > 0.05). In a low-temperature environment, mice fed sour and sweet diets showed a significant difference in the gut microbiota composition when compared to those fed a normal diet. A higher abundance of Lachnospiraceae, UBA1819, and Clostridiales was identified as the most significant taxa in the sour group, and a higher abundance of Ruminiclostridium was identified in the sweet group. These differences were associated with microbial pathways involved in carbohydrate metabolism, amino acid metabolism, and energy metabolism. A high-temperature environment exhibited only minor effects on the gut microbiota profile. Overall, our findings provide evidence for temperature-modulated responses to the taste, gut microbiota functions, and body weight changes in mice.

Quercetin influences intestinal dysbacteriosis and delays alveolar epithelial cell senescence by regulating PTEN/PI3K/AKT signaling in pulmonary fibrosis

Pulmonary fibrosis is a chronic and progressive lung disease with high mortality. This study aims to explore the protective mechanism of quercetin against pulmonary fibrosis regarding cell senescence and gut microbiota. Rats were intratracheally injected with bleomycin (BLM) to establish a pulmonary fibrosis rat model. RLE-6TN cells were stimulated with BLM to build the model of alveolar epithelial cell senescence, and RLE-6TN-derived conditional medium (CM) was harvested to further culture fibroblasts. Histopathological changes were assessed by H&E and Masson staining. α-SMA expression was assessed by immunofluorescence assay. Senescence-associated β-galactosidase (SA-β-gal) staining and senescence-associated secretory phenotype (SASP) cytokine assay were conducted to assess cellular senescence. Gut microbiota was analyzed by 16S rRNA gene sequencing. The fibrosis-, senescence-, and PTEN/PI3K/AKT signaling-related proteins were examined by western blot. In BLM-induced pulmonary fibrosis rats, quercetin exerted its protective effects by reducing histological injury and collagen deposition, lessening cellular senescence, and regulating gut microbiota. In BLM-induced alveolar epithelial cell senescence, quercetin inhibited senescence, lessened SASP cytokine secretion of alveolar epithelial cells, and further ameliorated collagen deposition in fibroblasts. In addition, quercetin might exert its functional effects by regulating the PTEN/PI3K/AKT signaling pathway. Moreover, quercetin regulated intestinal dysbacteriosis in BLM-induced pulmonary fibrosis rats, especially boosting the abundance of Akkermansia. To conclude, our findings provide an in-depth understanding of the potential mechanism behind the protective role of quercetin against pulmonary fibrosis.

Solanum nigrum L. berries extract ameliorated the alcoholic liver injury by regulating gut microbiota, lipid metabolism, inflammation, and oxidative stress

Solanum nigrum L. (SN) berry is an edible berry containing abundant polyphenols and bioactive compounds, which possess antioxidant and antiinflammatory properties. However, the effects of SN on alcohol-induced biochemical changes in the enterohepatic axis remain unclear. In the current study, a chronic ethanol-fed mice ALD model was used to test the protective mechanisms of SN berries. Microbiota composition was determined via 16S rRNA sequencing, we found that SN berries extract (SNE) improved intestinal imbalance by reducing the Firmicutes to Bacteroides ratio, restoring the abundance of Akkermansia microbiota, and reducing the abundance of Allobaculum and Shigella. SNE restored the intestinal short-chain fatty acids content. In addition, liver transcriptome data analysis revealed that SNE primarily affected the genes involved in lipid metabolism and inflammatory responses. Furthermore, SNE ameliorated hepatic steatosis in alcohol-fed mice by activating AMP-activated protein kinase (AMPK), acetyl-CoA carboxylase (ACC), peroxisome proliferator-activated receptor α (PPAR-α). SNE reduced the expression of toll-like receptor 4 (TLR4), myeloid differentiation factor-88 (MyD88) nuclear factor kappa-B (NF-κB), which can indicate that SNE mainly adjusted LPS/TLR4/MyD88/NF-κB pathway to reduce liver inflammation. SNE enhanced hepatic antioxidant capacity by regulating NRF2-related protein expression. SNE alleviates alcoholic liver injury by regulating of gut microbiota, lipid metabolism, inflammation, and oxidative stress. This study may provide a reference for the development and utilization of SN resources.

Effects of three Huanglian-derived polysaccharides on the gut microbiome and fecal metabolome of high-fat diet/streptozocin-induced type 2 diabetes mice

Plant-derived polysaccharides are important components for biological functions. The objective of this study is to study the mechanisms by which polysaccharides from three Huanglian (Rhizome Coptidis, HL) of Coptis chinensis, C. deltoidea, and Coptis teeta affect type 2 diabetes mellitus (T2DM) by analyzing the gut microbiome and their metabolites. A long-term high-fat diet (HFD) combined with streptozocin (STZ) induction was used to construct the T2DM mice model. The histopathology of liver, pancreas, and colon, biochemical indexes related to mice were determined to assess the ameliorative effects of these three HL polysaccharides (HLPs) on T2DM. The results indicated that oral HLPs improved hyperglycemia, insulin resistance, blood lipid levels, and β-cell function. Further, HLPs elevated the growth of advantageous beneficial bacteria within the gut microbiota and raised the concentrations of short-chain fatty acids (SCFAs), particularly butyric acid. Metabolic analyses showed that HLPs ameliorated the effects of T2DM on microbial-derived metabolites and related metabolic pathways, especially the biosynthetic pathways of phenylalanine, tyrosine, and tryptophan. In the combined analysis, many associations of T2DM-related biochemical indicators with gut microbes and their metabolites were extracted, which suggested the important role of gut microbiome and fecal metabolome in the amelioration of type 2 diabetes mellitus by HLPs.

Untargeted metabolomics analysis of probiotic jujube juice and its anti-obesity effects on high-fat-diet-induced obese mice

BACKGROUND

Dietary intervention, including polyphenol consumption, is recognized as an effective strategy to prevent obesity. Although fermented jujube juice (FJJ) with lactic acid bacteria has been shown to be rich in polyphenols and have strong antioxidant properties, little is known about its anti-obesity properties.

RESULTS

Untargeted metabolomics was employed to identify and analyze the differential metabolites between FJJ and raw jujube juice. A total of 431 metabolites belonging to diverse classes and with various functional active ingredients were quantitatively identified. The animal experiments results showed that FJJ administration for 13 weeks significantly inhibited high-fat-diet-induced body and epididymal adipose weight gain, and improved the serum lipid parameters in obese mice. Additionally, DNA-sequencing results revealed that FJJ treatment increased Akkermansia abundance in the gut and changed the composition of fecal microbiota by decreasing the Firmicutes/Bacteroidota ratio and Helicobacter pylori abundance.

CONCLUSION

These findings suggest that FJJ contributes to regulating lipid accumulation and gut microbiota composition in high-fat-diet-induced obese mice, which helps to prevent obesity. Hence, FJJ has the potential to be a beneficial beverage for controlling obesity. © 2024 Society of Chemical Industry.

L.acidophilus HSCC LA042 and HKL suspension ameliorate DSS-induced ulcerative colitis in mice by improving the intestinal barrier inhibiting the NLRP3 inflammasome and pathogenic bacteria

Ulcerative Colitis(UC) is a chronic intestinal inflammation affecting the intestines, yet its underlying causes remain unclear. In recent decades, the global prevalence of UC has been on the rise, leading to an increasing demand for therapeutic drugs with minimal side effects. Huan Kui Le (HKL), a traditional Chinese medicine compound, has demonstrated promising efficacy when combined with Lactobacillus acidophilus (Lac.) for UC intervention. However, the precise therapeutic mechanism of this combination remains unknown. The study focused on understanding the mechanisms of UC by examining the effects of Lac. and HKL (LH) treatment. The outcomes discovered that the disruption of gut microbiota, triggered by the activation of the NLRP3 inflammasome, plays a crucial role in UC development. This disruption exacerbates UC symptoms by causing disturbances in inflammatory cytokines and mucosal permeability. We investigated the dynamic changes following the application of this treatment using 16S rRNA sequencing, HE, WB, IHC, and ELISA. Compared with the UC group, LH treatment reduced colon pathological injury, improved colon length, and decreased IL-1 β serum levels. Furthermore, it restored the expression of TJs and preserved mucosal barrier integrity. LH treatment also mitigated colon injury by attenuating the expression of pyroptosis-related genes and proteins, such as NLRP3 and Caspase-1. Additionally, LH treatment altered the gut microbiota's microecology, characterized by a reduction in pathogenic bacteria abundance like Escherichia-shigella and an increase in beneficial bacteria abundance like Akkermansia and Erysipelatoclostridium. Overall, our findings indicate that LH therapy may be associated with intestinal barrier repair, inflammasome inhibition, and gut microbiota regulation, suggesting its potential as a UC treatment.

Multi-omics Study of Hypoxic-Ischemic Brain Injury After Cardiopulmonary Resuscitation in Swine

BACKGROUND

Hypoxic-ischemic brain injury is a common cause of mortality after cardiac arrest (CA) and cardiopulmonary resuscitation; however, the specific underlying mechanisms are unclear. This study aimed to explore postresuscitation changes based on multi-omics profiling.

METHODS

A CA swine model was established, and the neurological function was assessed at 24 h after resuscitation, followed by euthanizing animals. Their fecal, blood, and hippocampus samples were collected to analyze gut microbiota, metabolomics, and transcriptomics.

RESULTS

The 16S ribosomal DNA sequencing showed that the microbiota composition and diversity changed after resuscitation, in which the abundance of Akkermansia and Muribaculaceae_unclassified increased while the abundance of Bifidobacterium and Romboutsia decreased. A relationship was observed between CA-related microbes and metabolites via integrated analysis of gut microbiota and metabolomics, in which Escherichia-Shigella was positively correlated with glycine. Combined metabolomics and transcriptomics analysis showed that glycine was positively correlated with genes involved in apoptosis, interleukin-17, mitogen-activated protein kinases, nuclear factor kappa B, and Toll-like receptor signal pathways.

CONCLUSIONS

Our results provided novel insight into the mechanism of hypoxic-ischemic brain injury after resuscitation, which is envisaged to help identify potential diagnostic and therapeutic markers.

Genome- and Toxicology-Based Safety Assessment of Probiotic Akkermansia muciniphila ONE Isolated from Humans

In this study, the genome of Akkermansia muciniphila ONE (designated AKK ONE) was sequenced, assembled, and analyzed. In addition, the safety of this strain was further evaluated by toxicological studies. The results showed that the AKK ONE genome is contained on a single chromosome with a total length of 2,817,524 bp and an average GC content of 55.48%. In total, 2411, 1131, 1168, 1745, and 1402 genes were annotated to the NR, GO, KEGG, COG, and SwissProt database, respectively. Potential resistance genes, adeF, tetW, ANT(3″)-IIa, and aadA1 were detected. AKK ONE was sensitive to ampicillin, ceftriaxone, cefotaxime, meropenem, tetracycline, and chloramphenicol and resistant to moxifloxacin. No potential virulence-related genes were detected. The PathogenFinder database analysis showed that AKK ONE was a non-potential human pathogen. This strain had good gastroenteric fluid tolerance and a weak ability to colonize the gut. No test item-related adverse effects were observed in the acute and subchronic toxicity test. AKK ONE did not display mutagenic activity either. This strain did not change the hematological and clinical biochemical parameters of mice. The weights of the organs were not affected by AKK ONE treatment. These results support that AKK ONE is safe for use as a probiotic at a dose of 8.28 × 109 CFU/kg bw/day.

The Effect of the Lacticaseibacillus paracasei BEPC22 and Lactiplantibacillus plantarum BELP53 Combination (BN-202M) on Body Fat Percentage Loss in Overweight Individuals: A Randomized, Double-Blind, Placebo-Controlled Study

BN-202M is derived from humans and consists of two strains, Lacticaseibacillus paracasei BEPC22 and Lactiplantibacillus plantarum BELP53. Body fat reduction effect and safety of BN-202M were assessed in overweight participants. A total of 150 participants were randomly assigned to the BN-202M and placebo groups at a 1:1 ratio. Dual-energy X-ray absorptiometry was used to objectively measure body fat. After 12 weeks of oral administration, the body fat percentage (-0.10 ± 1.32% vs. 0.48 ± 1.10%; p = 0.009) and body fat mass (-0.24 ± 1.19 kg vs. 0.23 ± 1.05 kg; p = 0.023) of the BN-202M group decreased significantly compared to those of the placebo group. The body weight (-0.58 kg, p = 0.004) and body mass index (BMI; -0.23, p = 0.003) was found to decrease significantly at 12 weeks in the BN-202M group, but not in the placebo group. Metabolome analysis revealed that β-alanine, 3-aminoisobutyric acid, glutamic acid, and octopamine decreased in the weight-decreased BN-202M post-intake group. In the gut microbiota analysis, Akkermansia showed a statistically significant increase in the BN-202M group post-intake compared to the placebo group. No serious adverse events were observed in either group. These results suggest that BN-202M is safe and effective for reducing body fat and weight.

Utilization of Ningxiang pig milk oligosaccharides by Akkermansia muciniphila in vitro fermentation: enhancing neonatal piglet survival

Akkermansia muciniphila (A. muciniphila), an intestinal symbiont residing in the mucosal layer, shows promise as a probiotic. Our previous study found that the abundance of A. muciniphila was significantly higher in Ningxiang suckling piglets compared to other breeds, suggesting that early breast milk may play a crucial role. This study examines A. muciniphila's ability to utilize Ningxiang pig milk oligosaccharides. We discovered that A. muciniphila can thrive on both Ningxiang pig colostrum and purified pig milk oligosaccharides. Genetic analysis has shown that A. muciniphila harbors essential glycan-degrading enzymes, enabling it to effectively break down a broad spectrum of oligosaccharides. Our findings demonstrate that A. muciniphila can degrade pig milk oligosaccharides structures such as 3'-FL, 3'-SL, LNT, and LNnT, producing short-chain fatty acids in the process. The hydrolysis of these host-derived glycan structures enhances A. muciniphila's symbiotic interactions with other beneficial gut bacteria, contributing to a dynamic microbial ecological network. The capability of A. muciniphila to utilize pig milk oligosaccharides allows it to establish itself in the intestines of newborn piglets, effectively colonizing the mucosal layer early in life. This early colonization is key in supporting both mucosal and metabolic health, which is critical for enhancing piglet survival during lactation.

A Novel Foodstuff Mixture Improves the Gut-Liver Axis in MASLD Mice and the Gut Microbiota in Overweight/Obese Patients

Microbial community control is crucial for maintaining homeostasis of the gut-liver axis in metabolic dysfunction-associated steatotic liver disease (MASLD). Here, we show that supplementation with a mixture of Mexican foodstuffs (MexMix)-Opuntia ficus indica (nopal), Theobroma cacao (cocoa) and Acheta domesticus (crickets)-enriches several beneficial taxa in MASLD mice and overweight/obese humans. Thus, MexMix induces an important prebiotic effect. In mice, a restoration of intestinal health was observed due to the increased short-chain fatty acids (SCFAs) and intestinal crypt depth, Ocln and Cldn1 expression, and decreased Il6 and Tnfa expression. MexMix significantly reduced steatosis in the mice's liver and modified the expression of 1668 genes. By PCR, we corroborated a Tnfa and Pparg decrease, and a Cat and Sod increase. In addition, MexMix increased the hepatic NRF2 nuclear translocation and miRNA-34a, miRNA-103, and miRNA-33 decline. In overweight/obese humans, MexMix improved the body image satisfaction and reduced the fat intake. These findings indicate that this new food formulation has potential as a therapeutic approach to treat conditions associated with excessive consumption of fats and sugars.

Sheng-Jiang powder ameliorates NAFLD via regulating intestinal microbiota in mice

Background

Intestinal microbiota have been demonstrated to be involved in the development of NAFLD, while the relationship between the severity of NAFLD and intestinal microbiota is still not fully elucidated. Sheng-Jiang Powder (SJP) showed exact efficacy in treating SFL and great potential in regulating intestinal microbiota, but the effects need to be further addressed in NASH and liver fibrosis.

Objectives

To investigate the differences in intestinal microbiota of NAFLD with different severity and the effect of SJP on liver damage and intestinal microbiota.

Design

NAFLD mice models with different severity were induced by high-fat diet (HFD) or choline-deficient, L-amino acid-defined high-fat diet (CDAHFD) feeding and then treated with SJP/normal saline.

Methods

Biochemical blood tests, H&E/Masson/Oil Red O/IHC staining, Western blot, and 16SrDNA sequencing were performed to explore intestinal microbiota alteration in different NAFLD models and the effect of SJP on liver damage and intestinal microbiota.

Results

Intestinal microbiota alteration was detected in all NAFLD mice. SJP induced increased expression of Pparγ and alleviated liver lipid deposition in all NAFLD mice. Microbiome analysis revealed obvious changes in intestinal microbiota composition, while SJP significantly elevated the relative abundance of Roseburia and Akkermansia, which were demonstrated to be beneficial for improving inflammation and intestinal barrier function.

Conclusion

Our results demonstrated that SJP was effective in improving lipid metabolism in NAFLD mice, especially in mice with SFL. The potential mechanism may be associated with the regulation of intestinal microbiota.

An altered gut microbiome in pre-eclampsia: cause or consequence

Hypertensive disorders of pregnancy, including pre-eclampsia, are a leading cause of serious and debilitating complications that affect both the mother and the fetus. Despite the occurrence and the health implications of these disorders there is still relatively limited evidence on the molecular underpinnings of the pathophysiology. An area that has come to the fore with regard to its influence on health and disease is the microbiome. While there are several microbiome niches on and within the body, the distal end of the gut harbors the largest of these impacting on many different systems of the body including the central nervous system, the immune system, and the reproductive system. While the role of the microbiome in hypertensive disorders, including pre-eclampsia, has not been fully elucidated some studies have indicated that several of the symptoms of these disorders are linked to an altered gut microbiome. In this review, we examine both pre-eclampsia and microbiome literature to summarize the current knowledge on whether the microbiome drives the symptoms of pre-eclampsia or if the aberrant microbiome is a consequence of this condition. Despite the paucity of studies, obvious gut microbiome changes have been noted in women with pre-eclampsia and the individual symptoms associated with the condition. Yet further research is required to fully elucidate the role of the microbiome and the significance it plays in the development of the symptoms. Regardless of this, the literature highlights the potential for a microbiome targeted intervention such as dietary changes or prebiotic and probiotics to reduce the impact of some aspects of these disorders.

Tolypocladium sinense Mycelium Polysaccharide Alleviates Obesity, Lipid Metabolism Disorder, and Inflammation Caused by High Fat Diet via Improving Intestinal Barrier and Modulating Gut Microbiota

SCOPE

Tolypocladium sinense is a fungus isolated from Cordyceps. Cordyceps has some medicinal value and is also a daily health care product. This study explores the preventive effects of T. sinense mycelium polysaccharide (TSMP) on high-fat diet-induced obesity and chronic inflammation in mice.

METHODS AND RESULTS

Here, the study establishes an obese mouse model induced by high-fat diet. In this study, the mice are administered TSMP daily basis to evaluate its effect on alleviating obesity. The results show that TSMP can significantly inhibit obesity and alleviate dyslipidemia by regulating the expression of lipid metabolism-related genes such as liver kinase B1 (LKB1), phosphorylated AMP-activated protein kinase (pAMPK), peroxisome proliferator activated receptor α (PPARα), fatty acid synthase (FAS), and hydroxymethylglutaryl-CoA reductase (HMGCR) in the liver. TSMP can increase the protein expression of zona occludens-1 (ZO-1), Occludin, and Claudin-1 in the colon, improve the intestinal barrier dysfunction, and reduce the level of serum LPS, thereby reducing the inflammatory response. 16S rDNA sequencing shows that TSMP alters the intestinal microbiota by increasing the relative abundance of Akkermansia, Lactobacillus, and Prevotellaceae_NK3B31_group, while decreasing the relative abundance of Faecalibaculum.

CONCLUSION

The findings show that TSMP can inhibit obesity and alleviates obesity-related lipid metabolism disorders, inflammatory responses, and oxidative stress by modulating the gut microbiota and improving intestinal barrier.

Microbiome-Metabolome Analysis Insight into the Effects of the Extract of Phyllanthus emblica L. on High-Fat Diet-Induced Hyperlipidemia

The fruit of Phyllanthus emblica L. (FEPE) has a long history of use in Asian folk medicine. The main bioactive compounds in FEPE are polyphenols, known for their potent antioxidant, anti-inflammatory, and hypolipidemic activities. The present study aimed to investigate the intervention effect of FEPE (100 and 200 mg/kg) on hyperlipidemia for 8 weeks and preliminarily explored the potential mechanism by microbiome-metabolome analysis. The results showed that a high-dose FEPE (200 mg/kg) effectively alleviated dyslipidaemic symptoms and body weight gain in hyperlipidemic mice induced by a high-fat diet (HFD). Microbiome analysis showed that FEPE altered the structure of the intestinal microbiota, which included an increase in specific probiotics (such as Akkermansia, Anaerovorax, and Bacteroides) and a decrease in harmful bacteria (including A2, Acetitomaculum, Candidatus_Arthromitus, Lachnospiraceae_NK4A136_group, Lachnospiraceae_NK4B4_group, Rikenella, and Streptococcus), as well as a reduction in the level of short-chain fatty acids (SCFAs). In addition, significant changes in the hepatic metabolome were observed, and eight key metabolites associated with betaine metabolism, lysine degradation, methionine metabolism, and fatty acid metabolism pathways were primarily filtered. The correlated analysis identified several key "microbiota-metabolite" axes in the treatment of hyperlipidemia by FEPE extract. In conclusion, the present study is expected to provide a basis for treating hyperlipidemia with FEPE from the perspective of the microbiome-liver metabolome axis.

Akkermania muciniphila: a rising star in tumor immunology

Tumor is accompanied by complex and dynamic microenvironment development, and the interaction of all its components influences disease progression and response to treatment. Once the tumor microenvironment has been eradicated, various mechanisms can induce the tumors. Microorganisms can maintain the homeostasis of the tumor microenvironment through immune regulation, thereby inhibiting tumor development. Akkermania muciniphila (A. muciniphila), an anaerobic bacterium, can induce tumor immunity, regulate the gastrointestinal microenvironment through metabolites, outer membrane proteins, and some cytokines, and enhance the curative effect through combined immunization. Therefore, a comprehensive understanding of the complex interaction between A. muciniphila and human immunity will facilitate the development of immunotherapeutic strategies in the future and enable patients to obtain a more stable clinical response. This article reviews the most recent developments in the tumor immunity of A. muciniphila.

Effect of Lactobacillus plantarum BFS1243 on a female frailty model induced by fecal microbiota transplantation in germ-free mice

Frailty, a complex geriatric syndrome, significantly impedes the goal of achieving 'healthy aging'. Increasing evidence suggests a connection between gut microbiota, systemic inflammation, and disease. However, it remains to be determined whether interventions targeting the intestinal flora can effectively ameliorate frailty. Our research involved fecal microbiota transplantation (FMT) experiments on germ-free (GF) mice, dividing these mice into three groups: a group receiving transplants from healthy elderly individuals (HF group), a group of frailty patients (FF group), and the FF group supplemented with Lactobacillus plantarum BFS1243 (FFL group). Our findings indicated a significant shift in the gut microbiota of the FF group, in contrast to the HF group, characterized by decreased Akkermansia and increased Enterocloster, Parabacteroides, and Eisenbergiella. Concurrently, there was a reduction in amino acids and SCFAs, with BFS1243 partially mitigating these changes. The FF group exhibited an upregulation of inflammatory markers, including PGE2, CRP, and TNF-α, and a downregulation of irisin, all of which were moderated by BFS1243 treatment. Furthermore, BFS1243 improved intestinal barrier integrity and physical endurance in the FF mice. Correlation analysis revealed a negative association between SCFA-producing species and metabolites like lysine and butyric acid with pro-inflammatory factors. In conclusion, our study conclusively demonstrated that alterations in the gut microbiota of elderly individuals can lead to physical frailty, likely due to detrimental effects on the intestinal barrier and a pro-inflammatory state. These findings underscore the potential of gut microbiome modulation as a clinical strategy for treating frailty.

Effects of Gluten on Gut Microbiota in Patients with Gastrointestinal Disorders, Migraine, and Dermatitis

As gluten may trigger gastrointestinal disorders (GIDs), its presence or absence in the diet can change the diversity and proportion of gut microbiota. The effects of gluten after six weeks of a double-blind, placebo-controlled intervention with a gluten-free diet (GFD) were studied in participants with GIDs suffering from migraines and atopic dermatitis (n = 46). Clinical biomarkers, digestive symptoms, stool, the Migraine Disability Assessment questionnaire, and zonulin levels were analyzed. Next-generation sequencing was used to amplify the 16S rRNA gene of bacteria and the internal transcribed spacer (ITS) regions of fungi. The GFD increased Chao1 fungal diversity after the intervention, while the fungal composition showed no changes. Bacterial diversity and composition remained stable, but a positive association between bacterial and fungal Chao1 diversity and a negative association between Dothideomycetes and Akkermansia were observed. GIDs decreased in both groups and migraines improved in the placebo group. Our findings may aid the development of GID treatment strategies.

Priestia megaterium ASC-1 Isolated from Pickled Cabbage Ameliorates Hyperuricemia by Degrading Uric Acid in Rats

Pickled cabbage, a traditional fermented food rich in functional microorganisms, can effectively control hyperuricemia and gout. In this study, a Priestia megaterium ASC-1 strain with strong uric acid (UA) degradation ability was isolated from pickled cabbage. After oral administration for 15 days, ASC-1 was stably colonized in the rats in this study. ASC-1 significantly reduced UA levels (67.24%) in hyperuricemic rats. Additionally, ASC-1 alleviated hyperuricemia-related inflammatory response, oxidative stress, and blood urea nitrogen. Intestinal microbial diversity results showed that ASC-1 restored intestinal injury and gut flora dysbiosis caused by hyperuricemia. These findings suggest that P. megaterium ASC-1 may be used as a therapeutic adjuvant for the treatment of hyperuricemia.

Akkermansia muciniphila improves gastric cancer treatment by modulating the immune microenvironment

Background: Gut microbiota is pivotal in tumor occurrence and development, and there is a close relationship between Akkermansia muciniphila (AKK) and cancer immunotherapy. Methods: The effects of AKK and its outer membrane proteins on gastric cancer (GC) were evaluated in vitro and in vivo using cell counting kit-8 assay, flow cytometry, western blotting, ELISA, immunohistochemistry and immunofluorescence. Results: AKK outer membrane protein facilitated apoptosis of GC cells and exerted an immunostimulatory effect (by promoting M1 polarization of macrophages, enhancing expression of cytotoxic T-lymphocyte-related cytokines and suppressing that of Treg-related cytokines). Additionally, AKK and its formulation could inhibit tumor growth of GC and enhance the infiltration of immune cells in tumor tissues. Conclusion: AKK could improve GC treatment by modulating the immune microenvironment.

Microbiome bacterial influencers of host immunity and response to immunotherapy

The gut microbiota influences anti-tumor immunity and can induce or inhibit response to immune checkpoint inhibitors (ICIs). Therefore, microbiome features are being studied as predictive/prognostic biomarkers of patient response to ICIs, and microbiome-based interventions are attractive adjuvant treatments in combination with ICIs. Specific gut-resident bacteria can influence the effectiveness of immunotherapy; however, the mechanism of action on how these bacteria affect anti-tumor immunity and response to ICIs is not fully understood. Nevertheless, early bacterial-based therapeutic strategies have demonstrated that targeting the gut microbiome through various methods can enhance the effectiveness of ICIs, resulting in improved clinical responses in patients with a diverse range of cancers. Therefore, understanding the microbiota-driven mechanisms of response to immunotherapy can augment the success of these interventions, particularly in patients with treatment-refractory cancers.

Next-generation probiotics: the upcoming biotherapeutics

Recent and continuing advances in gut microbiome research have pointed out the role of the gut microbiota as an unexplored source of potentially beneficial probiotic microbes. Along the lines of these advances, both public awareness and acceptance of probiotics are increasing. That's why; academic and industrial research is dedicated to identifying and investigating new microbial strains for the development of next-generation probiotics (NGPs). At this time, there is a growing interest in NGPs as biotherapeutics that alter the gut microbiome and affect various diseases development. In this work, we have focused on some emergent and promising NGPs, specifically Eubacterium hallii, Faecalibacterium prausnitzii, Roseburia spp., Akkermansia muciniphila, and Bacteroides fragilis, as their presence in the gut can have an impact on the development of various diseases. Emerging studies point out the beneficial roles of these NGPs and open up novel promising therapeutic options. Interestingly, these NGPs were found to enhance gastrointestinal immunity, enhance immunotherapy efficacy in cancer patients, retain the intestinal barrier integrity, generate valuable metabolites, especially short-chain fatty acids, and decrease complications of chemotherapy and radiotherapy. Although many of these NGPs are considered promising for the prevention and treatment of several chronic diseases, research on humans is still lacking. Therefore, approval of these microbes from regulatory agencies is rare. Besides, some issues limit their wide use in the market, such as suitable methods for the culture and storage of these oxygen-sensitive microbes. The present review goes over the main points related to NGPs and gives a viewpoint on the key issues that still hinder their wide application. Furthermore, we have focused on the advancement in NGPs and human healthiness investigations by clarifying the limitations of traditional probiotic microorganisms, discussing the characteristics of emerging NGPs and defining their role in the management of certain ailments. Future research should emphasize the isolation, mechanisms of action of these probiotics, safety, and clinical efficacy in humans.

Effects of Lactobacillus-fermented low-protein diets on the growth performance, nitrogen excretion, fecal microbiota and metabolomic profiles of finishing pigs

This study investigated the effects of Lactobacillus-fermented low-protein diet on the growth performance, nitrogen balance, fecal microbiota, and metabolomic profiles of finishing pigs. A total of 90 finishing pigs were assigned to one of three dietary treatments including a normal protein diet (CON) as well as two experimental diets in which a low-protein diet supplemented with 0 (LP) or 1% Lactobacillus-fermented low-protein feed (FLP). In comparison with CON, the LP and FLP significantly increased average daily gain (P = 0.044), significantly decreased feed to gain ratio (P = 0.021), fecal nitrogen (P < 0.01), urine nitrogen (P < 0.01), and total nitrogen (P < 0.01), respectively. The LP group exhibited increased abundances of unclassified_f_Selenomonadaceae, Coprococcus, Faecalibacterium, and Butyricicoccus, while the abundances of Verrucomicrobiae, Verrucomicrobiales, Akkermansiaceae, and Akkermansia were enriched in the FLP group. Low-protein diet-induced metabolic changes were enriched in sesquiterpenoid and triterpenoid biosynthesis and Lactobacillus-fermented low-protein feed-induced metabolic changes were enriched in phenylpropanoid biosynthesis and arginine biosynthesis. Overall, low-protein diet and Lactobacillus-fermented low-protein diet improved the growth performance and reduce nitrogen excretion, possibly via altering the fecal microbiota and metabolites in the finishing pigs. The present study provides novel ideas regarding the application of the low-protein diet and Lactobacillus-fermented low-protein diet in swine production.

A digital twin of the infant microbiome to predict neurodevelopmental deficits

Despite the recognized gut-brain axis link, natural variations in microbial profiles between patients hinder definition of normal abundance ranges, confounding the impact of dysbiosis on infant neurodevelopment. We infer a digital twin of the infant microbiome, forecasting ecosystem trajectories from a few initial observations. Using 16S ribosomal RNA profiles from 88 preterm infants (398 fecal samples and 32,942 abundance estimates for 91 microbial classes), the model (Q-net) predicts abundance dynamics with R2 = 0.69. Contrasting the fit to Q-nets of typical versus suboptimal development, we can reliably estimate individual deficit risk (Mδ) and identify infants achieving poor future head circumference growth with ≈76% area under the receiver operator characteristic curve, 95% ± 1.8% positive predictive value at 98% specificity at 30 weeks postmenstrual age. We find that early transplantation might mitigate risk for ≈45.2% of the cohort, with potentially negative effects from incorrect supplementation. Q-nets are generative artificial intelligence models for ecosystem dynamics, with broad potential applications.

The secreted protein Amuc_1409 from Akkermansia muciniphila improves gut health through intestinal stem cell regulation

Akkermansia muciniphila has received great attention because of its beneficial roles in gut health by regulating gut immunity, promoting intestinal epithelial development, and improving barrier integrity. However, A. muciniphila-derived functional molecules regulating gut health are not well understood. Microbiome-secreted proteins act as key arbitrators of host-microbiome crosstalk through interactions with host cells in the gut and are important for understanding host-microbiome relationships. Herein, we report the biological function of Amuc_1409, a previously uncharacterised A. muciniphila-secreted protein. Amuc_1409 increased intestinal stem cell (ISC) proliferation and regeneration in ex vivo intestinal organoids and in vivo models of radiation- or chemotherapeutic drug-induced intestinal injury and natural aging with male mice. Mechanistically, Amuc_1409 promoted E-cadherin/β-catenin complex dissociation via interaction with E-cadherin, resulting in the activation of Wnt/β-catenin signaling. Our results demonstrate that Amuc_1409 plays a crucial role in intestinal homeostasis by regulating ISC activity in an E-cadherin-dependent manner and is a promising biomolecule for improving and maintaining gut health.

Bifidobacterium longum GL001 alleviates rat intestinal ischemia-reperfusion injury by modulating gut microbiota composition and intestinal tissue metabolism

Intestinal ischemia-reperfusion (IIR) injury leads to inflammation and oxidative stress, resulting in intestinal barrier damage. Probiotics, due to their anti-inflammatory and antioxidant properties, are considered for potential intervention to protect the intestinal barrier during IIR injury. Bifidobacterium longum, a recognized probiotic, has targeted effects on IIR injury, but its mechanisms of action are not yet understood. To investigate the mechanism of Bifidobacterium longum intervention in IIR injury, we conducted a study using a rat IIR injury model. The results showed that Bifidobacterium longum could alleviate inflammation and oxidative stress induced by IIR injury by suppressing the NF-κB inflammatory pathway and activating the Keap1/Nrf2 signaling pathway. Bifidobacterium longum GL001 also increased the abundance of the gut microbiota such as Oscillospira, Ouminococcus, Corynebacterium, Lactobacillus, and Akkermansia, while decreasing the abundance of Allobaculum, [Prevotella], Bacteroidaceae, Bacteroides, Shigella, and Helicobacter. In addition, Bifidobacterium longum GL001 reversed the changes in amino acids and bile acids induced by IIR injury and reduced the levels of DL-cysteine, an oxidative stress marker, in intestinal tissue. Spearman correlation analysis showed that L-cystine was positively correlated with Lactobacillus and negatively correlated with Shigella, while DL-proline was positively correlated with Akkermansia. Moreover, bile acids, cholic acid and lithocholic acid, were negatively correlated with Lactobacillus and positively correlated with Shigella. Therefore, Bifidobacterium longum GL001 may alleviate IIR injury by regulating the gut microbiota to modulate intestinal lipid peroxidation and bile acid metabolism.

Potential mitigation of titanium dioxide nanoparticles against 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis through inhibiting the canonical NF-κB pathway

Titanium dioxide nanoparticles (TiO2 NPs) have been widely employed in various industry fields, which makes consumers concerned about their health impact. Our previous work displayed that TiO2 NPs participated in the mitigation of TNBS-induced colitis, but the mechanism is still unknown. This work aimed to explore the role of oxidative stress and NF-κB pathway in the effect of TiO2 NPs on TNBS-induced colitis. The results showed that TiO2 NPs administration reduced the DAI score of colitis mice after TNBS enema. TiO2 NPs did not alter oxidative stress status (GSH/GSSG), but repaired the gut dysbacteriosis and inhibited the canonical NF-κB pathway activation in TNBS-induced colitis mice, manifested as a decrease in pathogenic bacteria and an increase in beneficial bacteria, as well as down-regulation of toll-like receptors (TLRs), IKKα, IKKβ, p65 and pro-inflammatory cytokines (IL-1β, IL-6, TNF-α and IFN-γ) in mRNA level, and the increased transcription of anti-inflammatory cytokines (IL-10, TGF-β, and IL-12), along with the declined protein level of TNF-α in TiO2 NPs treated colitis mice. The present study suggested that oral TiO2 NPs administration inhibited the canonical NF-κB pathway activation by repairing gut dysbacteriosis, which made a predominant role in alleviating colitis. These findings provided a new perspective for exploring the safety of TiO2 NPs.

The role of Akkermansia muciniphila in colorectal cancer: A double-edged sword of treatment or disease progression?

Colorectal cancer (CRC) is the second most cancer-related death worldwide. In recent years, probiotics have been used to reduce the potential risks of CRC and tumors with various mechanisms. Different bacteria have been suggested to play different roles in the progression, prevention, or treatment of CRC. Akkermansia muciniphila is considered a next-generation probiotic for preventing and treating some diseases. Therefore, in this review article, we aimed to describe and discuss different mechanisms of A. muciniphila as an intestinal microbiota or probiotic in CRC. Some studies suggested that the abundance of A. muciniphila was higher or increased in CRC patients compared to healthy individuals. However, the decreased abundance of A. muciniphila was associated with severe symptoms of CRC, indicating that A. muciniphila did not play a role in the development of CRC. In addition, A. muciniphila administration elevates gene expression of proliferation-associated molecules such as S100A9, Dbf4, and Snrpd1, or markers for cell proliferation. Some other studies suggested that inflammation and tumorigenesis in the intestine might promoted by A. muciniphila. Overall, the role of A. muciniphila in CRC development or inhibition is still unclear and controversial. Various methods of bacterial supplementation, such as viability, bacterial number, and abundance, could all influence the colonization effect of A. muciniphila administration and CRC progression. Overall, A. mucinipila has been revealed to modulate the therapeutic potential of immune checkpoint inhibitors. Preliminary human data propose that oral consumption of A. muciniphila is safe, but its efficacy needs to be confirmed in more human clinical studies.

The Effect of Akkermansia muciniphila and Its Outer Membrane Vesicles on MicroRNAs Expression of Inflammatory and Anti-inflammatory Pathways in Human Dendritic Cells

Probiotics play a crucial role in immunomodulation by regulating dendritic cell (DC) maturation and inducing tolerogenic DCs. Akkermansia muciniphila affects inflammatory response by elevating inhibitory cytokines. We aimed to evaluate whether Akkermansia muciniphila and its outer membrane vesicles (OMVs) affect microRNA-155, microRNA-146a, microRNA-34a, and let-7i expression of inflammatory and anti-inflammatory pathways. Peripheral blood mononuclear cells (PBMCs) were isolated from the healthy volunteers. To produce DCs, monocytes were cultivated with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). DCs were allocated into six subgroups: DC + Lipopolysaccharide (LPS), DC + dexamethasone, DC + A. muciniphila (MOI 100, 50), DC + OMVs (50 µg/ml), and DC + PBS. The surface expression of human leukocyte antigen-antigen D related (HLA-DR), CD86, CD80, CD83, CD11c, and CD14 was examined using flow cytometry, and the expression of microRNAs was assessed using qRT-PCR, and the levels of IL-12 and IL-10 were measured using ELISA. A. muciniphila (MOIs 50, 100) could significantly decrease IL-12 levels relative to the LPS group. The IL-10 levels were decreased in the DC + LPS group than the DC + dexamethasone group. Treatment with A. muciniphila (MOI 100) and OMVs could elevate the concentrations of IL-10. DC treatment with LPS led to a significant increment in the expression of microRNA-155, microRNA-34a, and microRNA-146a. The expression of these microRNAs was reversed by A. muciniphilia and its OMVs treatment. Let-7i increased in treatment groups compared to the DC + LPS group. A. muciniphilia (MOI 50) had a substantial effect on the expression of HLA-DR, CD80, and CD83 on DCs. Therefore, DCs treatment with A. muciniphila led to induce tolerogenic DCs and the production of anti-inflammatory IL-10.

The inhibitory effects of live and UV-killed Akkermansia muciniphila and its derivatives on cytotoxicity and inflammatory response induced by Clostridioides difficile RT001 in vitro

Clostridioides difficile infection (CDI) is the leading cause of healthcare-acquired infections worldwide. Probiotics are widely recommended to prevent CDI and its recurrences. Akkermansia muciniphila, as a therapeutic symbiont colonizing the intestinal mucosal layer, is considered to be a promising next-generation probiotic. In this work, we assessed the inhibitory effects of A. muciniphila MucT and its derivatives on cytotoxicity and inflammatory response induced by C. difficile RT001 in Caco-2 cells. The results obtained from SEM revealed that the morphology of UV-killed A. muciniphila remained unchanged after UV inactivation. TEM analysis showed that A. muciniphila-isolated extracellular vesicles (EVs) were spherical and ranged from 50 to 200 nm in size. Toxigenic supernatant (Tox-S) of C. difficile RT001 (500 μg/ml) significantly (P <0.01) reduced the cell viability of Caco-2 cells. Caco-2 cells treated with live (MOI 10), UV-killed (MOI 10), cell-free supernatant (CFS, 106 cfu/ml), and EVs (20 μg/ml) of A. muciniphila exhibited over 90% viability in comparison to untreated control. The neutralized CFS preparation using A. muciniphila and its derivatives could notably reduce the expression level of inflammatory markers. Additionally, A. muciniphila and its derivatives modulated the production of IL-1β, TNF-α, and IL-10 in Tox-S stimulated Caco-2 cells. We demonstrated that A. muciniphila and its derivatives can modulate changes in the gut barrier-related genes and inflammatory response caused by C. difficile Tox-S in Caco-2 cells.

Cross-talk between the gut microbiota and hypothyroidism: a bidirectional two-sample Mendelian randomization study

Background

Multiple observational studies suggest a connection between the composition of the gut microbiota and hypothyroidism. However, it has yet to be determined whether the gut microbiota has a causal effect on hypothyroidism.

Methods

To investigate the connection between the gut microbiota and hypothyroidism, two-sample Mendelian randomization was performed using data from a genome-wide association study meta-analysis (n = 18,430) conducted by the MiBioGen consortium. Summary statistics for hypothyroidism (26,342 cases and 59,827 controls) were obtained using the data from the FinnGen consortium R8 release data. To investigate the causal link between the gut microbiota and hypothyroidism, various methods, including MR-Egger, weighted median, weighted model, simple model, MR-PRESSO, and inverse variance weighted (IVW), were employed. The bacteria that were causally linked to hypothyroidism in forward Mendelian randomization analysis were subjected to reverse Mendelian randomization analysis. Cochran's Q statistics were utilized to gauge the heterogeneity of the instrumental variables.

Results

The results indicated that Akkermansia had a positive impact on hypothyroidism, with an odds ratio of 0.84 (95% CI 0.74-0.95, p = 0.01) based on the inverse variance-weighted estimates. Additionally, Anaerostipes (OR = 1.17, 95% CI 1.01-1.36, p = 0.04), Butyrivibrio (OR = 0.93, 95% CI 0.88-0.99, p = 0.02), Holdemania (OR = 0.89, 95% CI 0.81-0.99, p = 0.03), Intestinimonas (OR = 1.13, 95% CI 1.02-1.26, p = 0.03), Ruminiclostridium5 (OR = 1.19, 95% CI 1.01-1.41, p = 0.04), and Ruminococcaceae UCG-011 (OR = 0.91, 95% CI 0.84-0.99, p = 0.03) were identified. The gut microbiota was not significantly affected by hypothyroidism, as indicated by the results of the reverse MR analysis. There was no significant variation in the instrumental variables or horizontal pleiotropy.

Conclusion

The findings of this study using two-sample Mendelian randomization indicate a causal relationship between Akkermansia and hypothyroidism. Increased Akkermansia inhibits the onset and progression of hypothyroidism. Additional randomized controlled experiments are necessary to elucidate the beneficial impact of probiotics on hypothyroidism and their distinct protective mechanisms.