A next generation probiotic, Akkermansia muciniphila

Exposure to microcystin-LR promotes the progression of colitis-associated colorectal cancer by inducing barrier disruption and gut microbiota dysbiosis

Microcystins (MCs) are secondary metabolites generated by cyanobacterial blooms, among which microcystin-LR (MC-LR) stands out as the most widely distributed variant in aquatic environments. However, the effects of MC-LR on the colorectum and its role in promoting colorectal tumor progression remain unclear. Therefore, this study aims to scrutinize the impact of MC-LR on a mice model of colitis-associated colorectal cancer and elucidate the potential underlying molecular mechanisms. In this study, we used AOM/DSS mice and orally administered MC-LR at doses of 40 µg/kg or 200 µg/kg. Exposure to MC-LR increased tumor burden, promoted tumor growth, shortened colon size, and decreased goblet cell numbers and tight junction protein levels in intestinal tissues. Additionally, exposure to MC-LR induced alterations in the structure of gut microbiota in the mouse colon, characterized by an increase in the relative abundance of Escherichia_coli and Shigella_sonnei, and a decline in the relative abundance of Akkermansia_muciniphila. Transcriptomic analysis revealed that MC-LR exposure activated the IL-17 signaling pathway in mouse colorectal tissues and participated in inflammation regulation and immune response. Immunofluorescence results demonstrated an increase in T-helper 17 (Th17) cell levels in mouse colorectal tumors following MC-LR exposure. The results from RT-qPCR revealed that MC-LR induced the upregulation of IL-6, IL-1β, IL-10, IL-17A, TNF-α, CXCL1, CXCL2, CXCL5 and CCL20. The novelty of this study lies in its comprehensive approach to understanding the mechanisms by which MC-LR may contribute to CRC progression, offering new perspectives and valuable reference points for establishing guidance standards regarding MC-LR in drinking water. Our findings suggest that even at guideline value, MC-LR can have profound effects on susceptible mice, emphasizing the need for a reevaluation of guideline value and a deeper understanding of the role of environmental toxins in cancer progression.

Revitalizing gut health: Liangxue guyuan yishen decoction promotes akkermansia muciniphila -induced intestinal stem cell recovery post-radiation in mice

BACKGROUND

The efficacy of Liangxue Guyuan Yishen Decoction (LGYD), a traditional Chinese medicine, has been scientifically proven in the treatment of radiation-induced intestinal injury (RIII) and preservation of intestinal integrity and function following high-dose radiation exposure. However, further investigation is required to comprehensively elucidate the precise mechanisms underlying the therapeutic effects of LGYD in order to provide potential pharmaceutical options for radiation protection.

PURPOSE

This study aims to elucidate the potential mechanism through which LGYD exerts its therapeutic effects on RIII by modulating the gut microbiota (GM).

METHODS

16 s rRNA analysis was employed to assess the impact of varying doses of whole body irradiation (WBI) on GM in order to establish an appropriate model for this study. The effects of LGYD on GM and SCFA were evaluated using 16 s rRNA and Quantification of SCFA. UHPLC-QE-MS was utilized to identify the active components in LGYD as well as LGYD drug containing serum (LGYD-DS). Subsequently, immunofluorescence and immunohistochemical staining were conducted to validate the influence of LGYD and/or characteristic microbiota on RIII recovery in vivo. The effects of LGYD-DS, characteristic flora, and SCFA on intestinal stem cell (ISC) were assessed by measuring organoid surface area in intestinal organoid model.

RESULTS

The species composition and abundance of GM were significantly influenced by whole-body irradiation with a dose of 8.5 Gy, which was used as in vivo model. LGYD significantly improves the survival rate and promotes recovery from RIII. Additionally, LGYD exhibited a notable increase in the abundance of Akkermansia muciniphila (AKK) and levels of SCFA, particularly isobutyric acid. LGYD-DS consisted of seven main components derived from herbs of LGYD. In vivo experiments indicated that both LGYD and AKK substantially enhanced the survival rate after radiation and facilitated the recovery process for intestinal structure and function. In the organoid model, treatment with LGYD-DS, AKK supernatant or isobutyric acid significantly increased organoid surface area.

CONCLUSIONS

LGYD has the potential to enhance RIII by promoting the restoration of intestinal stem cell, which is closely associated with the upregulation of AKK abundance and production of SCFA, particularly isobutyric acid.

Intestinal Akkermansia muciniphila is Beneficial to Functional Recovery Following Ischemic Stroke

Recent studies have demonstrated the interaction between gut microbiota and brain on ischemic stroke, but the roles of gut microbiota in the pathophysiology of ischemic stroke remain largely unclear. In this study, we detected a significant increase of intestinal Akkermansia muciniphila (AKK) following ischemic stroke by a rose bengal photothrombosis model. To investigate the function and mechanism of AKK on ischemic stroke, we performed the AKK administration prior to stroke surgery. The results showed that mice treated with AKK gained significantly higher body weight and behaved better than those in PBS group at 3 days after ischemic stroke. Consistently, AKK administration remarkably decreased the infarct volumes as well as the density of degenerating neurons and apoptotic cells after ischemic stroke. Notably, AKK is a potential therapeutic target in immune-related disorders connected to the microbiota, and inflammation is crucially involved in the pathophysiological process of ischemic stroke. For the determination of underlying mechanisms of this protective effect, we investigated whether there are associations between AKK and neuroinflammation following ischemic stroke. The results suggested that AKK administration significantly reduced the activation of astrocytes and microglia but up-regulated multiple anti-inflammatory factors following ischemic stroke. Therefore, our study highlighted the beneficial roles of intestinal AKK on ischemic stroke and provided a new perspective for the treatment of ischemic stroke.

Leech Poecilobdella manillensis protein extract ameliorated hyperuricemia by restoring gut microbiota dysregulation and affecting serum metabolites

BACKGROUND

Hyperuricemia (HUA) is a public health concern that needs to be solved urgently. The lyophilized powder of Poecilobdella manillensis has been shown to significantly alleviate HUA; however, its underlying metabolic regulation remains unclear.

AIM

To explore the underlying mechanisms of Poecilobdella manillensis in HUA based on modulation of the gut microbiota and host metabolism.

METHODS

A mouse model of rapid HUA was established using a high-purine diet and potassium oxonate injections. The mice received oral drugs or saline. Additionally, 16S rRNA sequencing and ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry-based untargeted metabolomics were performed to identify changes in the microbiome and host metabolome, respectively. The levels of uric acid transporters and epithelial tight junction proteins in the renal and intestinal tissues were analyzed using an enzyme-linked immunosorbent assay.

RESULTS

The protein extract of Poecilobdella manillensis lyophilized powder (49 mg/kg) showed an enhanced anti-trioxypurine ability than that of allopurinol (5 mg/kg) (P < 0.05). A total of nine bacterial genera were identified to be closely related to the anti-trioxypurine activity of Poecilobdella manillensis powder, which included the genera of Prevotella, Delftia, Dialister, Akkermansia, Lactococcus, Escherichia_Shigella, Enterococcus, and Bacteroides. Furthermore, 22 metabolites in the serum were found to be closely related to the anti-trioxypurine activity of Poecilobdella manillensis powder, which correlated to the Kyoto Encyclopedia of Genes and Genomes pathways of cysteine and methionine metabolism, sphingolipid metabolism, galactose metabolism, and phenylalanine, tyrosine, and tryptophan biosynthesis. Correlation analysis found that changes in the gut microbiota were significantly related to these metabolites.

CONCLUSION

The proteins in Poecilobdella manillensis powder were effective for HUA. Mechanistically, they are associated with improvements in gut microbiota dysbiosis and the regulation of sphingolipid and galactose metabolism.

Akkermansia muciniphila Protects Against Antibiotic-Associated Diarrhea in Mice

Probiotics are used to prevent antibiotic-associated diarrhea (AAD) via the restoration of the gut microbiota. However, the precise effects of Akkermansia muciniphila (Akk), which is a promising probiotics, on AAD are unknown. Here, AAD models were established via the administration of lincomycin and ampicillin with or without pasteurized Akk or Amuc_1100 treatment. A diffusion test revealed that Akk was susceptible to the majority of the antibiotics, such as ampicillin. These effects were confirmed by the reduced Akk abundance in AAD model mice. Pasteurized Akk or Amuc_1100 significantly decreased the diarrhea status score and colon injury of AAD model mice. Additionally, these treatments significantly decreased the relative abundance of Citrobacter at genus level and reshaped the metabolic function of gut microbiota. Notably, pasteurized Akk or Amuc_1100 significantly changed the serum metabolome of AAD model mice. In addition, pasteurized Akk or Amuc_1100 suppressed intestinal inflammation by upregulating the expression of GPR109A and SLC5A8 and downregulating the expression of TNFα, IFNγ, IL1β, and IL6. Furthermore, they enhanced water and electrolyte absorption by upregulating AQP4, SLC26A3, and NHE3. Pasteurized Akk or Amuc_1100 also restored intestinal barrier function by ameliorating the downregulation of ZO-1, OCLN, CLDN4, and Muc2 in AAD model mice. In summary, optimizing intestinal health with pasteurized Akk or Amuc_1100 may serve as an approach for preventing AAD.

Multi-omics analysis reveals the impact of gut microbiota on antipsychotic-induced weight gain in schizophrenia

Emerging evidence indicates that gut microbial dysbiosis is associated with the development of antipsychotic-induced weight gain in schizophrenia (SZ). However, the exact taxonomic composition and functionality that constitute the "obesogenic" microbial profile remain elusive. Our retrospective survey identified two groups of the SZ population separated by BMI, with 1/3 of patients developing overweight/obesity after chronic antipsychotic treatment. Based on multi-omics analysis, we observed altered gut microbiota in SZ patients with overweight/obesity, characterized by a reduction in several beneficial bacteria genera, including Bacteroides, Parabacteroides, Akkermansia, and Clostridium. This microbial dysbiosis was accompanied by disrupted energy expenditure and nutritional metabolism, worsened metabolic indices, and reduced levels of beneficial metabolites, e.g. indole-3-carboxylic acid and propionic acid. Moreover, leveraging data from first-episode drug-naïve schizophrenia (FSZ) patients at one-month and one-year follow-up, both artificial neural network and random forest classifier-based prediction models demonstrated a strong ability of microbial profiles to predict antipsychotic-induced weight gain. Importantly, FSZ patients with higher relative abundance of Parabacteria distasonis were less susceptible to antipsychotic-induced weight gain. Thus, gut microbiota could serve as a noninvasive approach to predict antipsychotic-induced weight gain, guiding clinical antipsychotics administration and developing novel therapeutic strategies for weight management in SZ.

Metabolism of quercitrin in the colon and its beneficial regulatory effects on gut microbiota

BACKGROUND

Quercitrin is a dietary flavonoid widely found in plants with various physiological activities. However, whether quercitrin alters gut microbiota in vivo is not well understood. The aim of this study was to investigate metabolism of quercitrin in the colon and its regulation on gut microbiota in mice.

RESULTS

Herein, 22 flavonoids related to quercitrin metabolism were identified based on ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS). Gas chromatography and 16S rDNA gene sequencing were used to investigate short-chain fatty acid (SCFA) content and diversity of composition of gut microbiota, respectively. The results showed that quercitrin significantly alters the beta-diversity of the gut microbiota, probiotics such as Akkermansia and Lactococcus were significantly increased, and the production of propanoate, isovalerate and hexanoate of the quercitrin group were enhanced significantly. The Spearman's association analysis provided evidence that Gardnerella and Akkermansia have obvious correlations with most of quercitrin metabolites and SCFAs.

CONCLUSION

Quercitrin and its metabolites in the colon altered the structure of the mice gut microbiota and increased the content of SCFAs. Our experiments provide valuable insights into quercitrin research and application. © 2024 Society of Chemical Industry.

Supplementation of coated sodium butyrate relieved weaning stress and reshaped microbial flora in weaned lambs

Weaning is an important period in the growth and development of lambs. Thus, effectively reducing the occurrence of weaning stress is critical for maintaining lamb production. Coated sodium butyrate has been shown to reduce inflammation, promote intestinal health, and maintain homeostasis. However, the application and potential mechanism of coated sodium butyrate in alleviating weaning stress in lambs are still unclear. To evaluate the effects of coated sodium butyrate on the growth performance, antioxidant capacity, and gut microbiota of weaned lambs, 10 weaned lambs of 21-day-old were randomly divided into two groups: the CON group (basal diet) and the NaB group (basal diet +3 g/kg of coated sodium butyrate). The trial lasted 21 days. The experimental results showed that compared to the CON group, coated sodium butyrate supplementation in the diet significantly increased the average daily weight gain and daily feed intake of lambs (p < 0.05). In addition, compared to the CON group, the addition of coated sodium butyrate also significantly decreased the serum MDA level of lambs (p < 0.05). Notably, the addition of coated sodium butyrate did not have a significant effect on the cecal microbiota, while increasing the diversity of colonic microbiota and promoting the abundance of Lachnospiraceae, Verrucomicrobiota, Akkermansia, Roseburia, and Sinobacteraceae, which are associated with the nutrient absorption of lambs (p < 0.05). These results indicate that dietary supplementation with coated sodium butyrate could promote the growth and antioxidant capacity of weaned lambs and alleviate weaning stress.

Urolithin B protects mice from diet-induced obesity, insulin resistance, and intestinal inflammation by regulating gut microbiota composition

The increasing prevalence of obesity and type 2 diabetes (T2D) signifies the failure of conventional treatments for these diseases. The gut microbiota has been proposed as a key player in the pathophysiology of diet-induced T2D. Urolithin B (Uro B), a gut microbiota-derived polyphenol metabolite, exerts several beneficial health effects. In this study, we investigated the metabolic effects of Uro B on high-fat/high-sucrose (HFHS)-fed mice and determined whether its antidiabetic effects are related to the modulation of the gut microbiota. C57BL/6J mice were fed either a chow or HFHS diet. HFHS-fed mice were administered daily with either a vehicle (water) or different doses of Uro B (100 or 200 mg kg-1) for eight weeks. The composition of the gut microbiota was assessed by 16S rRNA sequencing. The results showed that Uro B treatment reduced HFHS-induced weight gain and visceral obesity and decreased liver weight and triglyceride accumulation associated with blunted hepatic oxidative stress and inflammation. Furthermore, Uro B administration improved insulin sensitivity as revealed by improved insulin tolerance, a lower homeostasis model assessment of insulin resistance, and decreased glucose-induced hyperinsulinemia during the oral glucose tolerance test. Uro B treatment was found to lower the intestinal triglyceride content and alleviate intestinal inflammation and oxidative stress. Remarkably, Uro B treatment markedly increased the proportion of the mucin-degrading bacterium Akkermansia in metagenomic samples. In conclusion, Uro B exerts beneficial metabolic effects by alleviating HFHS diet-induced features of metabolic syndrome, which is associated with a proportional increase in the population of Akkermansia spp.

Natural polysaccharides as promising reno-protective agents for the treatment of various kidney injury

Renal injury, a prevalent clinical outcome with multifactorial etiology, imposes a substantial burden on society. Currently, there remains a lack of effective management and treatments. Extensive research has emphasized the diverse biological effects of natural polysaccharides, which exhibit promising potential for mitigating renal damage. This review commences with the pathogenesis of four common renal diseases and the shared mechanisms underlying renal injury. The renoprotective roles of polysaccharides in vivo and in vitro are summarized in the following five aspects: anti-oxidative stress effects, anti-apoptotic effects, anti-inflammatory effects, anti-fibrotic effects, and gut modulatory effects. Furthermore, we explore the structure-activity relationship and bioavailability of polysaccharides in relation to renal injury, as well as investigate their utility as biomaterials for alleviating renal injury. The clinical experiments of polysaccharides applied to patients with chronic kidney disease are also reviewed. Broadly, this review provides a comprehensive perspective on the research direction of natural polysaccharides in the context of renal injury, with the primary aim to serve as a reference for the clinical development of polysaccharides as pharmaceuticals and prebiotics for the treatment of kidney diseases.

Intestinal microbiota imbalance resulted by anti-Toxoplasma gondii immune responses aggravate gut and brain injury

BACKGROUND

Toxoplasma gondii infection affects a significant portion of the global population, leading to severe toxoplasmosis and, in immunocompromised patients, even death. During T. gondii infection, disruption of gut microbiota further exacerbates the damage to intestinal and brain barriers. Therefore, identifying imbalanced probiotics during infection and restoring their equilibrium can regulate the balance of gut microbiota metabolites, thereby alleviating tissue damage.

METHODS

Vimentin gene knockout (vim-/-) mice were employed as an immunocompromised model to evaluate the influence of host immune responses on gut microbiota balance during T. gondii infection. Behavioral experiments were performed to assess changes in cognitive levels and depressive tendencies between chronically infected vim-/- and wild-type (WT) mice. Fecal samples were subjected to 16S ribosomal RNA (rRNA) sequencing, and serum metabolites were analyzed to identify potential gut probiotics and their metabolites for the treatment of T. gondii infection.

RESULTS

Compared to the immunocompetent WT sv129 mice, the immunocompromised mice exhibited lower levels of neuronal apoptosis and fewer neurobehavioral abnormalities during chronic infection. 16S rRNA sequencing revealed a significant decrease in the abundance of probiotics, including several species of Lactobacillus, in WT mice. Restoring this balance through the administration of Lactobacillus murinus and Lactobacillus gasseri significantly suppressed the T. gondii burden in the intestine, liver, and brain. Moreover, transplantation of these two Lactobacillus spp. significantly improved intestinal barrier damage and alleviated inflammation and neuronal apoptosis in the central nervous system. Metabolite detection studies revealed that the levels of various Lactobacillus-related metabolites, including indole-3-lactic acid (ILA) in serum, decreased significantly after T. gondii infection. We confirmed that L. gasseri secreted much more ILA than L. murinus. Notably, ILA can activate the aromatic hydrocarbon receptor signaling pathway in intestinal epithelial cells, promoting the activation of CD8+ T cells and the secretion of interferon-gamma.

CONCLUSION

Our study revealed that host immune responses against T. gondii infection severely disrupted the balance of gut microbiota, resulting in intestinal and brain damage. Lactobacillus spp. play a crucial role in immune regulation, and the metabolite ILA is a promising therapeutic compound for efficient and safe treatment of T. gondii infection.

Impacts of liver macrophages, gut microbiota, and bile acid metabolism on the differences in iHFC diet-induced MASH progression between TSNO and TSOD mice

BACKGROUND

Tsumura-Suzuki non-obese (TSNO) mice exhibit a severe form of metabolic dysfunction-associated steatohepatitis (MASH) with advanced liver fibrosis upon feeding a high-fat/cholesterol/cholate-based (iHFC) diet. Another ddY strain, Tsumura-Suzuki diabetes obese (TSOD) mice, are impaired in the progression of iHFC diet-induced MASH.

AIM

To elucidate the underlying mechanisms contributing to the differences in MASH progression between TSNO and TSOD mice.

METHODS

We analyzed differences in the immune system, gut microbiota, and bile acid metabolism in TSNO and TSOD mice fed with a normal diet (ND) or an iHFC diet.

RESULTS

TSOD mice had more anti-inflammatory macrophages in the liver than TSNO mice under ND feeding, and were impaired in the iHFC diet-induced accumulation of fibrosis-associated macrophages and formation of histological hepatic crown-like structures in the liver. The gut microbiota of TSOD mice also exhibited a distinct community composition with lower diversity and higher abundance of Akkermansia muciniphila compared with that in TSNO mice. Finally, TSOD mice had lower levels of bile acids linked to intestinal barrier disruption under iHFC feeding.

CONCLUSIONS

The dynamics of liver macrophage subsets, and the compositions of the gut microbiota and bile acids at steady state and post-onset of MASH, had major impacts on MASH development.

Research trends of next generation probiotics

Gut represents one of the largest interfaces for the interaction of host factors and the environmental ones. Gut microbiota, largely dominated by bacterial community, plays a significant role in the health status of the host. The healthy gut microbiota fulfills several vital functions such as energy metabolism, disease protection, and immune modulation. Dysbiosis, characterized by microbial imbalance, can contribute to the development of various disorders, including intestinal, systemic, metabolic, and neurodegenerative conditions. Probiotics offer the potential to address dysbiosis and improve overall health. Advancements in high-throughput sequencing, bioinformatics, and omics have enabled mechanistic studies for the development of bespoke probiotics, referred to as next generation probiotics. These tailor-made probiotics have the potential to ameliorate specific disease conditions and thus fulfill the specific consumer needs. This review discusses recent updates on the most promising next generation probiotics, along with the challenges that must be addressed to translate this concept into reality.

Coprococcus eutactus screened from healthy adolescent attenuates chronic restraint stress-induced depression-like changes in adolescent mice: Potential roles in the microbiome and neurotransmitter modulation

The onset of depression commonly occurs in adolescence; therefore, depressive prevention and intervention are pivotal during this period. It is becoming evident that neurotransmitter imbalance and gut microbiota dysbiosis are prominent causes of depression. However, the underlying links and mechanisms remain poorly understood. In this study, with 16S ribosomal RNA gene sequencing, genus Coprococcus markedly differentiated between the healthy and unmedicated depressive adolescents. Based on this, transplantation of Coprococcus eutactus (C.e.) was found to dramatically ameliorate the chronic restraint stress (CRS) induced depression-like changes and prevent synaptic loss and glial-stimulated neuroinflammation in mice. The Ultra-high performance liquid chromatography tandem mass spectrometry analysis (UHPLC-MS/MS) further showed that neurotoxic neurotransmitters in kynurenine pathway (KP) such as 3-hydroxykynurenine (3-HK) and 3-hydroxyanthranilic acid (3-HAA) decreased in mouse brains, mechanistically deciphering the transfer of the tryptophan metabolic pathway to serotonin metabolic signaling in the brain after C.e. treatment, which was also verified in the colon. Molecularly, blockage of KP activities mediated by C.e. was ascribed to the restraint of the limit-step enzymes responsible for kynurenine, 3-HK, and quinolinic acid generation. In the colon, C.e. treatment significantly recovered goblet cells and mucus secretion in CRS mice which may ascribe to the rebalance of the disordered gut microbiota, especially Akkermansia, Roseburia, Rikenella, Blautia, and Alloprevotella. Taken together, the current study reveals for the first time the beneficial effects and potential mechanisms of C.e. in ameliorating CRS-induced depression, unraveling the direct links between C.e. treatment and neurotransmitter rebalance, which may provide efficacious therapeutic avenues for adolescent depressive intervention.

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.

Pediococcus pentosaceus MIANGUAN2 Alleviates Influenza Virus Infection by Modulating Gut Microbiota and Enhancing Short-Chain Fatty Acid Production

Influenza, a severe respiratory disease caused by the influenza virus, has long been a prominent threat to human health. An increasing number of studies have demonstrated that oral administration with probiotics may increase the immune response to lung infection via the gut-lung axis leading to the alleviation of the pulmonary disease. In this study, we evaluated the effects of oral administration of Pediococcus pentosaceus MIANGUAN2 (MIANGUAN2) on influenza infection in a mouse model. Our results showed that oral administration of MIANGUAN2 significantly improved weight loss, lung index, and lung pathology, and decreased lung viral load of influenza-infected mice. Additionally, MIANGUAN2-treated mice showed significantly lower levels of TNF-α, IL-1β, IFN-γ, and IL-12p70 and higher production of IL-4 in the lung. In accordance with this, the transcriptome analysis of the lung indicated that MIANGUAN2-treated mice had reduced expression of inflammation markers, such as TNF, apoptosis, and the NF-Kappa B pathway. Furthermore, the administration of MIANGUAN2 restored the SCFAs profiles through regulating the gut microbiota. SCFA-producing bacteria, such as p_Firmicutes, f_Lachnospiraceae, and f_Ruminococcaceae, were enriched in the MIANGUAN2-treated group compared with PBS-treated group. Consistently, the concentrations of SCFAs in the MIANGUAN2 group were significantly higher than those in the PBS-treated group. In addition, the concentrations of SCFAs were positively correlated with SCFA-producing bacteria, such as Ruminococcus, while being negatively correlated with the virial titers and proinflammatory cytokines. In conclusion, this animal study suggests that Pediococcus pentosaceus MIANGUAN2 may alleviate the influenza infection by altering the gut microbiota composition and increasing the levels of gut microbiota-derived SCFAs.

Gynostemma pentaphyllum Extract Alleviates NASH in Mice: Exploration of Inflammation and Gut Microbiota

NASH (non-alcoholic steatohepatitis) is a severe liver disease characterized by hepatic chronic inflammation that can be associated with the gut microbiota. In this study, we explored the therapeutic effect of Gynostemma pentaphyllum extract (GPE), a Chinese herbal extract, on methionine- and choline-deficient (MCD) diet-induced NASH mice. Based on the peak area, the top ten compounds in GPE were hydroxylinolenic acid, rutin, hydroxylinoleic acid, vanillic acid, methyl vanillate, quercetin, pheophorbide A, protocatechuic acid, aurantiamide acetate, and iso-rhamnetin. We found that four weeks of GPE treatment alleviated hepatic confluent zone inflammation, hepatocyte lipid accumulation, and lipid peroxidation in the mouse model. According to the 16S rRNA gene V3-V4 region sequencing of the colonic contents, the gut microbiota structure of the mice was significantly changed after GPE supplementation. Especially, GPE enriched the abundance of potentially beneficial bacteria such as Akkerrmansia and decreased the abundance of opportunistic pathogens such as Klebsiella. Moreover, RNA sequencing revealed that the GPE group showed an anti-inflammatory liver characterized by the repression of the NF-kappa B signaling pathway compared with the MCD group. Ingenuity Pathway Analysis (IPA) also showed that GPE downregulated the pathogen-induced cytokine storm pathway, which was associated with inflammation. A high dose of GPE (HGPE) significantly downregulated the expression levels of the tumor necrosis factor-α (TNF-α), myeloid differentiation factor 88 (Myd88), cluster of differentiation 14 (CD14), and Toll-like receptor 4 (TLR4) genes, as verified by real-time quantitative PCR (RT-qPCR). Our results suggested that the therapeutic potential of GPE for NASH mice may be related to improvements in the intestinal microenvironment and a reduction in liver inflammation.

Administering Lactiplantibacillus fermentum F6 decreases intestinal Akkermansia muciniphila in a dextran sulfate sodium-induced rat colitis model

Probiotics are increasingly used to manage gut dysbiosis-related conditions due to their robust ability to manipulate the gut microbial community. However, few studies have reported that probiotics can specifically modulate individual gut microbes. This study demonstrated that administering the probiotic, Lactiplantibacillus fermentum F6, could ameliorate dextran sulfate sodium-induced colitis in a rat model, evidenced by the decreases in the disease activity index score, histopathology grading, and serum pro-inflammatory cytokine levels, as well as the increase in the serum anti-inflammatory cytokine levels. Shotgun metagenomics revealed that the fecal metagenomic of colitis rats receiving the probiotic intervention contained substantially fewer Akkermansia muciniphila than the dextran sulfate sodium group. Thus, the probiotic mechanism might be exerted by reducing specific gut microbial species associated with disease pathogenesis. A new paradigm for designing probiotics that manage diseases through direct and precise manipulation of gut microbes has been provided through this study.

Akkermansia muciniphila isolated from forest musk deer ameliorates diarrhea in mice via modification of gut microbiota

BACKGROUND

The forest musk deer, a rare fauna species found in China, is famous for its musk secretion which is used in selected Traditional Chinese medicines. However, over-hunting has led to musk deer becoming an endangered species, and their survival is also greatly challenged by various high incidence and high mortality respiratory and intestinal diseases such as septic pneumonia and enteritis. Accumulating evidence has demonstrated that Akkermannia muciniphila (AKK) is a promising probiotic, and we wondered whether AKK could be used as a food additive in animal breeding programmes to help prevent intestinal diseases.

METHODS

We isolated one AKK strain from musk deer feces (AKK-D) using an improved enrichment medium combined with real-time PCR. After confirmation by 16S rRNA gene sequencing, a series of in vitro tests was conducted to evaluate the probiotic effects of AKK-D by assessing its reproductive capability, simulated gastrointestinal fluid tolerance, acid and bile salt resistance, self-aggregation ability, hydrophobicity, antibiotic sensitivity, hemolysis, harmful metabolite production, biofilm formation ability, and bacterial adhesion to gastrointestinal mucosa.

RESULTS

The AKK-D strain has a probiotic function similar to that of the standard strain in humans (AKK-H). An in vivo study found that AKK-D significantly ameliorated symptoms in the enterotoxigenic Escherichia coli (ETEC)-induced murine diarrhea model. AKK-D improved organ damage, inhibited inflammatory responses, and improved intestinal barrier permeability. Additionally, AKK-D promoted the reconstitution and maintenance of the homeostasis of gut microflora, as indicated by the fact that AKK-D-treated mice showed a decrease in Bacteroidetes and an increase in the proportion of other beneficial bacteria like Muribaculaceae, Muribaculum, and unclassified f_Lachnospiaceae compared with the diarrhea model mice.

CONCLUSION

Taken together, our data show that this novel AKK-D strain might be a potential probiotic for use in musk deer breeding, although further extensive systematic research is still needed.

A syrup containing L-arabinose and D-xylose appears superior to PEG-4000 as a bowel cleansing agent

Adequate bowel cleansing is crucial for endoscopic diagnosis and treatment, and the recovery of gut microbiota after intestinal cleansing is also important. A hypertonic syrup predominantly comprising L-arabinose and D-xylose (20% xylo-oligosaccharides) can be extracted from the hemicellulose of corn husks and cobs. L-Arabinose and xylo-oligosaccharides have been reported to relieve constipation and improve the gut microbial environment. This study evaluated the bowel cleansing effect of the aforementioned syrup and its influence on the organism and intestinal microbiota after cleansing in comparison with polyethylene glycol-4000 (PEG-4000) in mice. Bowel cleansing was performed using syrup or PEG-4000 in C57BL/6J mice, and the effect of intestinal preparation and its influence on serum electrolytes and gut microbiota after bowel cleansing were evaluated. The volume of intestinal residual feces in the syrup group was significantly lower than that in the PEG-4000 group. Additionally, syrup disturbed serum electrolytes more mildly than PEG-4000. Alpha diversity in the gut microbiota was significantly higher in the syrup group than in the PEG-4000 group on the first day after bowel cleansing. However, no difference in beta diversity was observed between the two groups. Syrup increased the abundance of Bifidobacteria and Christensenella and decreased the abundance of Akkermansia in comparison with PEG-4000 on the first day after bowel cleansing. Thus, this syrup has potential clinical use as a bowel cleansing agent given the above effects, its benefits and safety, and better taste and acceptability.

Diet-driven differential response of Akkermansia muciniphila modulates pathogen susceptibility

The erosion of the colonic mucus layer by a dietary fiber-deprived gut microbiota results in heightened susceptibility to an attaching and effacing pathogen, Citrobacter rodentium. Nevertheless, the questions of whether and how specific mucolytic bacteria aid in the increased pathogen susceptibility remain unexplored. Here, we leverage a functionally characterized, 14-member synthetic human microbiota in gnotobiotic mice to deduce which bacteria and functions are responsible for the pathogen susceptibility. Using strain dropouts of mucolytic bacteria from the community, we show that Akkermansia muciniphila renders the host more vulnerable to the mucosal pathogen during fiber deprivation. However, the presence of A. muciniphila reduces pathogen load on a fiber-sufficient diet, highlighting the context-dependent beneficial effects of this mucin specialist. The enhanced pathogen susceptibility is not owing to altered host immune or pathogen responses, but is driven by a combination of increased mucus penetrability and altered activities of A. muciniphila and other community members. Our study provides novel insights into the mechanisms of how discrete functional responses of the same mucolytic bacterium either resist or enhance enteric pathogen susceptibility.

Dual engineered bacteria improve inflammatory bowel disease in mice

Currently, there are many different therapies available for inflammatory bowel disease (IBD), including engineered live bacterial therapeutics. However, most of these studies focus on producing a single therapeutic drug using individual bacteria, which may cause inefficacy. The use of dual drugs can enhance therapeutic effects. However, expressing multiple therapeutic drugs in one bacterial chassis increases the burden on the bacterium and hinders good secretion and expression. Therefore, a dual-bacterial, dual-drug expression system allows for the introduction of two probiotic chassis and enhances both therapeutic and probiotic effects. In this study, we constructed a dual bacterial system to simultaneously neutralize pro-inflammatory factors and enhance the anti-inflammatory pathway. These bacteria for therapy consist of Escherichia coli Nissle 1917 that expressed and secreted anti-TNF-α nanobody and IL-10, respectively. The oral administration of genetically engineered bacteria led to a decrease in inflammatory cell infiltration in colon and a reduction in the levels of pro-inflammatory cytokines. Additionally, the administration of engineered bacteria did not markedly aggravate gut fibrosis and had a moderating effect on intestinal microbes. This system proposes a dual-engineered bacterial drug combination treatment therapy for inflammatory bowel disease, which provides a new approach to intervene and treat IBD. KEY POINTS: • The paper discusses the effects of using dual engineered bacteria on IBD • Prospects of engineered bacteria in the clinical treatment of IBD.

Heterologous expression of P9 from Akkermansia muciniphila increases the GLP-1 secretion of intestinal L cells

Glucagon-like peptide-1(GLP-1) is an incretin hormone secreted primarily from the intestinal L-cells in response to meals. GLP-1 is a key regulator of energy metabolism and food intake. It has been proven that P9 protein from A. muciniphila could increase GLP-1 release and improve glucose homeostasis in HFD-induced mice. To obtain an engineered Lactococcus lactis which produced P9 protein, mature polypeptide chain of P9 was codon-optimized, fused with N-terminal signal peptide Usp45, and expressed in L. lactis NZ9000. Heterologous secretion of P9 by recombinant L. lactis NZP9 were successfully detected by SDS-PAGE and western blotting. Notably, the supernatant of L. lactis NZP9 stimulated GLP-1 production of NCI-H716 cells. The relative expression level of GLP-1 biosynthesis gene GCG and PCSK1 were upregulated by 1.63 and 1.53 folds, respectively. To our knowledge, this is the first report on the secretory expression of carboxyl-terminal processing protease P9 from A. muciniphila in L. lactis. Our results suggest that genetically engineered L. lactis which expressed P9 may have therapeutic potential for the treatment of diabetes, obesity and other metabolic disorders.

Optimizing Akkermansia muciniphila Isolation and Cultivation: Insights into Gut Microbiota Composition and Potential Growth Promoters in a Chinese Cohort

The study aims to analyze the composition of the gut microbiota in Chinese individuals using metagenomic sequencing technology, with a particular focus on the abundance of Akkermansia muciniphila (Akk). To improve the efficiency of Akk isolation and identification accuracy, modifications were made to the enrichment culture medium and 16S rRNA universal primers. Additionally, potential growth-promoting factors that stimulate Akk growth were explored through in vitro screening. The research results revealed that the abundance of Akk in Chinese fecal samples ranged from 0.004% to 0.4%. During optimization, a type of animal protein peptide significantly enhanced the enrichment efficiency of Akk, resulting in the isolation of three Akk strains from 14 fecal samples. Furthermore, 17 different growth-promoting factors were compared, and four factors, including galactose, sialic acid, lactose, and chitosan, were identified as significantly promoting Akk growth. Through orthogonal experiments, the optimal ratio of these four growth-promoting factors was determined to be 1:1:2:1. After adding 1.25% of this growth-promoting factor combination to the standard culture medium, Akk was cultivated at 37° for 36 h, achieving an OD600nm value of 1.169, thus realizing efficient proliferation and optimized cultivation of Akk. This study provides important clues for a deeper understanding of the gut microbiota composition in Chinese individuals, while also offering effective methods for the isolation and cultivation of Akk, laying the groundwork for its functional and application research in the human body.

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.

Comparative analysis of growth and health of juvenile African catfish (Clarias gariepinus) fed with different starch diets

This study evaluated the effects of potato, wheat, rice, and corn starch on growth performance, blood parameters, digestive enzyme activity, antioxidative response, and gut microbiota of African catfish, Clarias gariepinus. A control diet (a commercial fish diet) and four different starch (potato, PO; wheat, WH; corn, CO; rice, RC) formulations were fed to African catfish with average weight of 10.5g (n = 30) for eight weeks. The experiment was conducted in triplicates. At the end of the feeding trial, the growth performance of African catfish fed with potato starch (PO) was significantly higher than other treatment groups. Furthermore, this group recorded significant and lowest feed conversion ratio (FCR) compared to other groups. Meanwhile, there were no significant differences in all tested hematological parameters and antioxidative response between the groups. Digestive enzyme activities in the fish intestines, including amylase, lipase, and protease, were significantly higher in African catfish fed with the PO diet. In addition, this group demonstrated substantially lower viscerosomatic index (VSI) and hepatosomatic index (HSI) than other groups, indicating that the fish has more meat on its body. The PO diet group also recorded significantly higher Akkermansia muciniphila, a good gut microbiota. Therefore, the PO diet potentially improves African catfish's growth performance and health status.

Unlocking the power of postbiotics: A revolutionary approach to nutrition for humans and animals

Postbiotics, which comprise inanimate microorganisms or their constituents, have recently gained significant attention for their potential health benefits. Extensive research on postbiotics has uncovered many beneficial effects on hosts, including antioxidant activity, immunomodulatory effects, gut microbiota modulation, and enhancement of epithelial barrier function. Although these features resemble those of probiotics, the stability and safety of postbiotics make them an appealing alternative. In this review, we provide a comprehensive summary of the latest research on postbiotics, emphasizing their positive impacts on both human and animal health. As our understanding of the influence of postbiotics on living organisms continues to grow, their application in clinical and nutritional settings, as well as animal husbandry, is expected to expand. Moreover, by substituting postbiotics for antibiotics, we can promote health and productivity while minimizing adverse effects. This alternative approach holds immense potential for improving health outcomes and revolutionizing the food and animal products industries.

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.

Correlation between the gut microbiome and neurodegenerative diseases: a review of metagenomics evidence

A growing body of evidence suggests that the gut microbiota contributes to the development of neurodegenerative diseases via the microbiota-gut-brain axis. As a contributing factor, microbiota dysbiosis always occurs in pathological changes of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. High-throughput sequencing technology has helped to reveal that the bidirectional communication between the central nervous system and the enteric nervous system is facilitated by the microbiota's diverse microorganisms, and for both neuroimmune and neuroendocrine systems. Here, we summarize the bioinformatics analysis and wet-biology validation for the gut metagenomics in neurodegenerative diseases, with an emphasis on multi-omics studies and the gut virome. The pathogen-associated signaling biomarkers for identifying brain disorders and potential therapeutic targets are also elucidated. Finally, we discuss the role of diet, prebiotics, probiotics, postbiotics and exercise interventions in remodeling the microbiome and reducing the symptoms of neurodegenerative diseases.

Bioactives and metabolites of Tetrastigma hemsleyanum root extract alleviate DSS-induced ulcerative colitis by targeting the SYK protein in the B cell receptor signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Tetrastigma hemsleyanum is an endemic Chinese herb with a wide range of pharmacological activities, including anti-inflammatory, antiviral, antioxidant, antitumor, and immunomodulatory activities. However, the effect and mechanisms of the anti-inflammatory activity of T. hemsleyanum root extract against dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) have not yet been fully investigated.

AIM OF THE STUDY

This study aimed to explore the therapeutic effect and molecular mechanisms of T. hemsleyanum root extract in DSS-induced UC mice and knockdown cells.

MATERIALS AND METHODS

T. hemsleyanum root extract was obtained and analyzed by high-performance liquid chromatography (HPLC). The therapeutic effects of T. hemsleyanum root extract on DSS-induced UC mice were evaluated by the disease activity index (DAI) score, colon length, serum inflammatory cytokines and oxidant/antioxidant levels, and histopathological features of the ileum and colon. Genome-wide gene expression profiles of ileal and colonic tissues were collected by transcriptomics, and signaling pathways were analyzed by the KEGG database. UC-related pathways were uploaded to the STRING database, then the protein-protein interactions (PPIs) were determined by Cytoscape, and the enriched genes were evaluated by real-time quantitative PCR (qPCR). The protein-ligand complexes were docked by AutoDock, and the genes were knocked down in Caco-2 cells by shRNA. The non-targeted metabolomic profiling of ileal contents was analyzed by ultra-high-performance liquid chromatography (UHPLC), and gut microflora were sequenced by an Illumina MiSeq System.

RESULTS

Ten components that alleviated UC symptoms in mice by decreasing the DAI and serum inflammatory cytokines and oxidant levels, promoting intestinal development, and increasing serum antioxidant levels were identified in T. hemsleyanum root extract. T. hemsleyanum root extract activated the B cell receptor signaling pathway in the colon tissue of UC mice, in which two components, rutin and astragaline, bound to the spleen tyrosine kinase (SYK) protein but also restored gut microflora diversity and increased the proportion of probiotics. Furthermore, metabolites of T. hemsleyanum root extract were involved in vitamin metabolism, fatty acid metabolism, and ferroptosis.

CONCLUSIONS

The rutin and astragaline components of T. hemsleyanum root extract, by binding to SYK protein, activated the B cell receptor signaling pathway and restored gut microflora diversity to alleviate UC symptoms in mice.

Inulin protects against the harmful effects of dietary emulsifiers on mice gut microbiome

Background

The prevalence of inflammatory bowel diseases is increasing, especially in developing countries, with adoption of Western-style diet. This study aimed to investigate the effects of two emulsifiers including lecithin and carboxymethyl cellulose (CMC) on the gut microbiota, intestinal inflammation and the potential of inulin as a means to protect against the harmful effects of emulsifiers.

Methods

In this study, male C57Bl/6 mice were divided into five groups (n:6/group) (control, CMC, lecithin, CMC+inulin, and lecithin+inulin). Lecithin and CMC were diluted in drinking water (1% w/v) and inulin was administered daily at 5 g/kg for 12 weeks. Histological examination of the ileum and colon, serum IL-10, IL-6, and fecal lipocalin-2 levels were analyzed. 16S rRNA gene V3-V4 region amplicon sequencing was performed on stool samples.

Results

In the CMC and lecithin groups, shortening of the villus and a decrease in goblet cells were observed in the ileum and colon, whereas inulin reversed this effect. The lipocalin level, which was 9.7 ± 3.29 ng in the CMC group, decreased to 4.1 ± 2.98 ng with the administration of inulin. Bifidobacteria and Akkermansia were lower in the CMC group than the control, while they were higher in the CMC+inulin group. In conclusion, emulsifiers affect intestinal health negatively by disrupting the epithelial integrity and altering the composition of the microbiota. Inulin is protective on their harmful effects. In addition, it was found that CMC was more detrimental to microbiota composition than lecithin.

Data-driven prediction of colonization outcomes for complex microbial communities

Microbial interactions can lead to different colonization outcomes of exogenous species, be they pathogenic or beneficial in nature. Predicting the colonization of exogenous species in complex communities remains a fundamental challenge in microbial ecology, mainly due to our limited knowledge of the diverse mechanisms governing microbial dynamics. Here, we propose a data-driven approach independent of any dynamics model to predict colonization outcomes of exogenous species from the baseline compositions of microbial communities. We systematically validate this approach using synthetic data, finding that machine learning models can predict not only the binary colonization outcome but also the post-invasion steady-state abundance of the invading species. Then we conduct colonization experiments for commensal gut bacteria species Enterococcus faecium and Akkermansia muciniphila in hundreds of human stool-derived in vitro microbial communities, confirming that the data-driven approaches can predict the colonization outcomes in experiments. Furthermore, we find that while most resident species are predicted to have a weak negative impact on the colonization of exogenous species, strongly interacting species could significantly alter the colonization outcomes, e.g., Enterococcus faecalis inhibits the invasion of E. faecium invasion. The presented results suggest that the data-driven approaches are powerful tools to inform the ecology and management of microbial communities.

Gut microbiota and metabolic biomarkers in metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease (MASLD), a replacement of the nomenclature employed for NAFLD, is the most prevalent chronic liver disease worldwide. Despite its high global prevalence, NAFLD is often under-recognized due to the absence of reliable noninvasive biomarkers for diagnosis and staging. Growing evidence suggests that the gut microbiome plays a significant role in the occurrence and progression of NAFLD by causing immune dysregulation and metabolic alterations due to gut dysbiosis. The rapid advancement of sequencing tools and metabolomics has enabled the identification of alterations in microbiome signatures and gut microbiota-derived metabolite profiles in numerous clinical studies related to NAFLD. Overall, these studies have shown a decrease in α-diversity and changes in gut microbiota abundance, characterized by increased levels of Escherichia and Prevotella, and decreased levels of Akkermansia muciniphila and Faecalibacterium in patients with NAFLD. Furthermore, bile acids, short-chain fatty acids, trimethylamine N-oxide, and tryptophan metabolites are believed to be closely associated with the onset and progression of NAFLD. In this review, we provide novel insights into the vital role of gut microbiome in the pathogenesis of NAFLD. Specifically, we summarize the major classes of gut microbiota and metabolic biomarkers in NAFLD, thereby highlighting the links between specific bacterial species and certain gut microbiota-derived metabolites in patients with NAFLD.

Therapeutic Potential of Bacteroides fragilis SNBF-1 as a Next-Generation Probiotic: In Vitro Efficacy in Lipid and Carbohydrate Metabolism and Antioxidant Activity

This study explores the potential of aerotolerant Bacteroides fragilis (B. fragilis) strains as next-generation probiotics (NGPs), focusing on their adaptability in the gastrointestinal environment, safety profile, and probiotic functions. From 23 healthy infant fecal samples, we successfully isolated 56 beneficial B. fragilis strains. Notably, the SNBF-1 strain demonstrated superior cholesterol removal efficiency in HepG2 cells, outshining all other strains by achieving a remarkable reduction in cholesterol by 55.38 ± 2.26%. Comprehensive genotype and phenotype analyses were conducted, including sugar utilization and antibiotic sensitivity tests, leading to the development of an optimized growth medium for SNBF-1. SNBF-1 also demonstrated robust and consistent antioxidant activity, particularly in cell-free extracts, as evidenced by an average oxygen radical absorbance capacity value of 1.061 and a 2,2-diphenyl-1-picrylhydrazyl scavenging ability of 94.53 ± 7.31%. The regulation of carbohydrate metabolism by SNBF-1 was assessed in the insulin-resistant HepG2 cell line. In enzyme inhibition assays, SNBF-1 showed significant α-amylase and α-glucosidase inhibition, with rates of 87.04 ± 2.03% and 37.82 ± 1.36%, respectively. Furthermore, the cell-free supernatant (CFS) of SNBF-1 enhanced glucose consumption and glycogen synthesis in insulin-resistant HepG2 cells, indicating improved cellular energy metabolism. This was consistent with the observation that the CFS of SNBF-1 increased the proliferation of HepG2 cells by 123.77 ± 0.82% compared to that of the control. Overall, this research significantly enhances our understanding of NGPs and their potential therapeutic applications in modulating the gut microbiome.

Gut Microbiota and Biomarkers of Intestinal Barrier Damage in Cirrhosis

Gut dysbiosis and subclinical intestinal damage are common in cirrhosis. The aim of this study was to examine the association of intestinal damage biomarkers (diamine oxidase [DAO], claudin 3, and intestinal fatty acid binding protein [I-FABP; FABP2]) with the state of the gut microbiota in cirrhosis. The blood levels of DAO were inversely correlated with blood levels of claudin 3, lipopolysaccharide (LPS), presepsin, TNF-α, and the severity of cirrhosis according to Child-Pugh scores. The blood level of I-FABP was directly correlated with the blood level of claudin 3 but not with that of DAO. Patients with small intestinal bacterial overgrowth (SIBO) had lower DAO levels than patients without SIBO. There was no significant difference in claudin 3 levels and I-FABP detection rates between patients with and without SIBO. The DAO level was directly correlated with the abundance of Akkermansiaceae, Akkermansia, Allisonella, Clostridiaceae, Dialister, Lactobacillus, Muribaculaceae, Negativibacillus, Ruminococcus, Thiomicrospiraceae, Verrucomicrobiae, and Verrucomicrobiota; and it was inversely correlated with the abundance of Anaerostipes, Erysipelatoclostridium, and Vibrio. The I-FABP level was directly correlated with Anaerostipes, Bacteroidia, Bacteroidota, Bilophila, Megamonas, and Selenomonadaceae; and it was inversely correlated with the abundance of Brucella, Pseudomonadaceae, Pseudomonas, and Vibrionaceae. The claudin 3 level was directly correlated with Anaerostipes abundance and was inversely correlated with the abundance of Brucella, Coriobacteriia, Eggerthellaceae, and Lactobacillus.

Qi-Zhi-Wei-Tong granules alleviates chronic non-atrophic gastritis in mice by altering the gut microbiota and bile acid metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional Chinese medicine, Qi-zhi-wei-tong granule (QZWT) significantly reduced the major gastrointestinal and psychological symptoms of functional dyspepsia.

AIM OF THE STUDY

We aimed to explore the therapeutic effect of QZWT treated chronic non-atrophic gastritis (CNAG) and to elucidate its potential mechanism.

MATERIALS AND METHODS

The composition of QZWT was analysed by UPLC-Q/TOF-MS. The CNAG mice model was established by chronic restraint stress (CRS) in combination with iodoacetamide (IAA). Morphological staining was utilized to reveal the impact of QZWT on stomach and gut integrity. RT‒qPCR and ELISA were used to measure proinflammatory cytokines in the stomach, colon tissues and serum of CNAG mice. Next-generation sequencing of 16 S rDNA was applied to analyse the gut microbiota community of faecal samples. Finally, we investigated the faecal bile acid composition using GC‒MS.

RESULTS

Twenty-one of the compounds from QZWT were successfully identified by UPLC-Q/TOF-MS analysis. QZWT enhanced gastric and intestinal integrity and suppressed inflammatory responses in CNAG mice. Moreover, QZWT treatment reshaped the gut microbiota structure by increasing the levels of the Akkermansia genus and decreasing the populations of the Desulfovibrio genus in CNAG mice. The alteration of gut microbiota was associated with gut bacteria BA metabolism. In addition, QZWT reduced BAs and especially decreased conjugated BAs in CNAG mice. Spearman's correlation analysis further confirmed the links between the changes in the gut microbiota and CNAG indices.

CONCLUSIONS

QZWT can effectively inhibited gastrointestinal inflammatory responses of CNAG symptoms in mice; these effects may be closely related to restoring the balance of the gut microbiota and regulating BA metabolism to protect the gastric mucosa. This study provides a scientific reference for the pathogenesis of CNAG and the mechanism of QZWT treatment.

Isoquercitrin alleviates lipopolysaccharide-induced intestinal mucosal barrier damage in mice by regulating TLR4/MyD88/NF-κB signaling pathway and intestinal flora

Intestinal mucosal barrier damage is closely associated with the development of several intestinal inflammatory diseases. Isoquercitrin (IQ) is a natural flavonoid compound derived from plants, which exhibits high antioxidant and anti-inflammatory activity with minimal side effects in humans. Therefore, it shows great potential for preventing and treating intestinal mucosal barrier damage. This study aims to investigate the ameliorative effect and mechanism of IQ on lipopolysaccharide (LPS)-induced intestinal mucosal barrier damage in mice. The mice were treated with IQ for 7 days and then injected with LPS to induce intestinal mucosal barrier damage. The results revealed that IQ treatment alleviated LPS-induced intestinal mucosal barrier damage in mice, which can be evidenced by the improvements in intestinal morphology and the promotion of expression in intestinal tight junctions (ZO-1, Claudin-1, and Occludin), as well as MUC2 mucin. IQ also attenuated intestinal inflammatory responses by inhibiting the TLR4/MyD88/NF-κB signaling pathway and reducing the expression and plasma levels of IL-6, IL-1β, and TNF-α. Furthermore, IQ significantly increased the relative abundance of beneficial bacteria, including Dubosiella, Akkermansia muciniphila and Faecalibaculum rodentium, while suppressing the growth of harmful bacteria such as Mucispirillum schaedleri in the intestinal flora of mice. Consequently, IQ can alleviate the LPS-induced intestinal mucosal barrier damage in mice by inhibiting the TLR4/MyD88/NF-κB signaling pathway and modulating the intestinal flora.

Akkermansia muciniphila MucT attenuates sodium valproate-induced hepatotoxicity and upregulation of Akkermansia muciniphila in rats

In the previous study, we found that the oral sodium valproate (SVP) increased the relative abundance of Akkermansia muciniphila (A. muciniphila) in rats, and plasma aspartate transaminase (AST) and alanine aminotransferase (ALT) activities were positively correlated with A. muciniphila levels. This study aimed to further investigate the role of A. muciniphila in SVP-induced hepatotoxicity by orally supplementing rats with the representative strain of A. muciniphila, A. muciniphila MucT. Additionally, the fresh faeces were incubated anaerobically with SVP to investigate the effect of SVP on faecal A. muciniphila in the absence of host influence. Results showed that A. muciniphila MucT ameliorated the hepatotoxicity and upregulation of A. muciniphila induced by SVP. SVP also induced a noteworthy elevation of A. muciniphila level in vitro, supporting the observation in vivo. Therefore, we speculate that A. muciniphila MucT may be a potential therapeutic strategy for SVP-induced hepatotoxicity. In addition, the increased A. muciniphila induced by SVP may differ from A. muciniphila MucT, but further evidence is needed. These findings provide new insights into the relationships between A. muciniphila and SVP-induced hepatotoxicity, highlighting the potential for different A. muciniphila strains to have distinct or even opposing effects on SVP-induced hepatotoxicity.

Akkermansia muciniphila and Alcohol-Related Liver Diseases. A Systematic Review

SCOPE

Akkermansia muciniphila (A. muciniphila) are Gram negative commensal bacteria, degrading mucin in the intestinal mucosa, modulating intestinal permeability and inflammation in the digestive tract, liver, and blood. Some components can promote the relative abundance of A. muciniphila in the gut microbiota, but lower levels of A. muciniphila are more commonly found in people with obesity, diabetes, metabolic syndromes, or inflammatory digestive diseases. Over-intake of ethanol can also induce a decrease of A. muciniphila, associated with dysregulation of microbial metabolite production, impaired intestinal permeability, induction of chronic inflammation, and production of cytokines.

METHODS AND RESULTS

Using a PRISMA search strategy, a review is performed on the bacteriological characteristics of A. muciniphila, the factors capable of modulating its relative abundance in the digestive tract and its probiotic use in alcohol-related liver diseases (alcoholic hepatitis, cirrhosis, hepatocellular carcinoma, hepatic transplantation, partial hepatectomy).

CONCLUSION

Several studies have shown that supplementation with A. muciniphila can improve ethanol-related hepatic pathologies, and highlight the interest in using this bacterial species as a probiotic.

The Microbial Tryptophan Metabolite Contributes to the Remission of Salmonella typhimurium Infection in Mice

Salmonella enterica serovar Typhimurium (S. Tm) causes severe foodborne diseases. Interestingly, gut microbial tryptophan (Trp) metabolism plays a pivotal role in such infections by a yet unknown mechanism. This study aimed to explore the impact of Trp metabolism on S. Tm infection and the possible mechanisms involved. S. Tm-infected C57BL6/J mice were used to demonstrate the therapeutic benefits of the Bacillus velezensis JT3-1 (B. velezensis/JT3-1) strain or its cell-free supernatant in enhancing Trp metabolism. Targeted Trp metabolomic analyses indicated the predominance of indole-3-lactic acid (ILA), an indole derivative and ligand for aryl hydrocarbon receptor (AHR). Based on the 16S amplicon sequencing and correlation analysis of metabolites, we found that B. velezensis supported the relative abundance of Lactobacillus and Ligilactobacillus in mouse gut and showed positive correlations with ILA levels. Moreover, AHR and its downstream genes (especially IL-22) significantly increased in mouse colons after B. velezensis or cell-free supernatant treatment, suggesting the importance of AHR pathway activation. In addition, ILA was found to stimulate primary mouse macrophages to secrete IL-22, which was antagonized by CH-223191. Furthermore, ILA could protect mice from S. Tm infection by increasing IL-22 in Ahr+/- mice, but not in Ahr-/- mice. Finally, Trp-rich feeding showed amelioration of S. Tm infection in mice, and the effect depended on gut microbiota. Taken together, these results suggest that B. velezensis-associated ILA contributes to protecting mice against S. Tm infection by activating the AHR/IL-22 pathway. This study provides insights into the involvement of microbiota-derived Trp catabolites in protecting against Salmonella infection.

Quinoa protein and its hydrolysate ameliorated DSS-induced colitis in mice by modulating intestinal microbiota and inhibiting inflammatory response

The objective of this study was to investigate the protective effects of quinoa protein (QPro) and its derived peptides (QPep) in dextran sulfate sodium (DSS)-induced colitis in mice. The results demonstrated that oral administration of QPro and QPep significantly alleviated colitis symptoms, including diarrhea, abdominal pain, bloody stools, weight loss, as well as reduced colonic shortening, inflammatory factor release, and intestinal barrier injury. Short-chain fatty acids (SCFAs) production rose as QPro and QPep modulated the composition of the intestinal microbiota. Western blotting results revealed that QPro and QPep also suppressed TLR4 levels and inhibited IκB-α and NF-κB phosphorylation in colon tissue, implying that the TLR4/IκB-α/NF-κB signaling pathway may be involved in the amelioration of QPro and QPep in DSS-induced colitis. These results indicate the potential of quinoa protein and its hydrolysate to serve as bioactive components in functional diets for intestinal health and to significantly lower intestinal inflammation.

Diet-driven differential response of Akkermansia muciniphila modulates pathogen susceptibility

The erosion of the colonic mucus layer by a dietary fiber-deprived gut microbiota results in heightened susceptibility to an attaching and effacing pathogen, Citrobacter rodentium. Nevertheless, the questions of whether and how specific mucolytic bacteria aid in the increased pathogen susceptibility remain unexplored. Here, we leverage a functionally characterized, 14-member synthetic human microbiota in gnotobiotic mice to deduce which bacteria and functions are responsible for the pathogen susceptibility. Using strain dropouts of mucolytic bacteria from the community, we show that Akkermansia muciniphila renders the host more vulnerable to the mucosal pathogen during fiber deprivation. However, the presence of A. muciniphila reduces pathogen load on a fiber-sufficient diet, highlighting the context-dependent beneficial effects of this mucin specialist. The enhanced pathogen susceptibility is not owing to altered host immune or pathogen responses, but is driven by a combination of increased mucus penetrability and altered activities of A. muciniphila and other community members. Our study provides novel insights into the mechanisms of how discrete functional responses of the same mucolytic bacterium either resist or enhance enteric pathogen susceptibility.

Effects of secretin gene knockout on the diversity, composition, and function of gut microbiota in adult male mice

The gut microbiota plays a vital role in maintaining gastrointestinal homeostasis, however, whether it is influenced by gut hormones remains unknown. Secretin is a well-known gastrointestinal hormone produced by enteroendocrine S cells. This study utilized 16S rRNA amplicon sequencing to characterize the effect of SCT deficiency on the gut microbiota. Our results show that systemic SCT knockout alters the composition and abundance of the mouse gut microbiota but does not affect fecal short-chain fatty acids and lipids concentrations. At the genus level, the abundance of Turicibacter, Bacteroides, Ruminococcu, Romboutsia, Asaccharobacter, and Parasutterella increased in SCT-/- mice, whereas the abundance of Akkermansia and Escherichia decreased. Functional prediction results showed that lack of SCT reduced the abundance of carbohydrate metabolism-related pathways but increased the abundance of linoleic acid metabolism and branched-chain amino acid degradation. Overall, systemic SCT knockout had only minor effects on gut microbiota composition and function in adult male mice fed a standard chow diet.

Metagenomics study on taxonomic and functional change of gut microbiota in patients with obesity with PCOS treated with exenatide combination with metformin or metformin alone

OBJECTIVE

To investigate the effect of exenatide treatment on the composition of intestinal flora and metabolic pathways in patients with obesity with polycystic ovary syndrome.

METHODS

Patients with obesity with polycystic ovary syndrome (PCOS) were distributed to two groups: one received exenatide combined with metformin (COM group, n = 14) and the other used metformin alone (MF group, n = 15). Fresh fecal specimens from the participants, including 29 patients with obesity with PCOS and 6 healthy controls, were collected for metagenomic sequencing. The effect of exenatide combination with metformin or metformin alone on the composition and function of intestinal flora in patients with obesity with PCOS were compared by bioinformatics analysis.

RESULTS

The level of BMI, TT, HbA1c, and HDL-c was significantly improved in both groups. The MF and COM groups were abundant in Firmicutes, Bacteroidetes, Uroviricota, Actinobacteria, and Proteobacteria. Abundance of Bacteroidetes, Proteobacteria, Hungatella, and certain probiotics like Phocaeicola and Anaerobutyricum significantly increased in both groups after treatment. Enriched microbial species in the MF and COM group were different. Clostridium, Fusobacterium, and Oxalobacter were the main bacteria in the post-MF group, while Lactococcus_garvieae, Clostridium_perfringens, and Coprococcus_sp_AF16_5 were the main bacteria in the post-COM group. The post-COM group had more probiotic species including Bifidobacterium, Prevotella, and Anaerobutyricum after treatment.

CONCLUSION

Both exenatide combined with metformin and metformin monotherapy can improve metabolic and endocrine markers, and the diversity and abundance of gut microbiota in patients with obesity with PCOS. The effects of the combination and monotherapy agents on intestinal flora were consistent to some extent but also unique respectively.

Research trends on the relationship between Helicobacter pylori and microbiota: A bibliometric analysis

BACKGROUND

Increasing evidence has indicated that Helicobacter pylori infection is associated with the complex microbiota in the digestive tract of the human body. We aimed to assess the research trends and hotspots in the field of H. pylori and microbiota using a quantitative method.

MATERIALS AND METHODS

The clinical studies on H. pylori and microbiota published from 2001 to 2022 were extracted from the Web of Science database. We visualized and analyzed countries/regions, institutions, authors, journals, and keywords through VOSviewer and CiteSpace software. The test techniques, specimen type, as well as microbiota variation after H. pylori infection and eradication were also evaluated.

RESULTS

A total of 98 publications were finally identified, and the number of annual papers increased gradually. China showed its dominant position in the publication outputs, and Nanchang University was the most productive institution. Cong He, Xu Shu, and Yin Zhu published the highest number of papers, whereas Helicobacter was the most productive journal. "Helicobacter pylori" ranked highest in the keyword occurrences. 16S rRNA gene sequencing was the most frequently used method for microbiota analysis. Fecal samples had the highest frequency of use, followed by gastric mucosa and saliva. H. pylori infection was associated with the alterations of microbiota through the digestive tract, characterized by the enrichment of Helicobacter in the stomach. Triple and quadruple therapy were the most utilized eradication regimens, and probiotics supplementation therapy has been proven to reduce side effects and restore microbial diversity.

CONCLUSIONS

This bibliometric analysis provides an overview of advancements in the field of H. pylori and microbiota. While numerous studies have been conducted on the correlation between H. pylori and the alterations of microbiota, future research is warranted to investigate the mechanisms underlying the interplay between H. pylori and other microbes in the development of related diseases.

Probiotics, prebiotics, and postbiotics in health and disease

The gut microbiota and its homeostasis play a crucial role in human health. However, for some diseases related to the gut microbiota, current traditional medicines can only relieve symptoms, and it is difficult to solve the root causes or even cause side effects like disturbances in the gut microbiota. Increasing clinical studies and evidences have demonstrated that probiotics, prebiotics, and postbiotics can prevent and treat various diseases, but currently they can only be used as dietary supplements rather than medicines, which restricts the application of probiotics in the field of medicine. Here, this review analyzes the importance of gut microbiota in human health and the current problems of traditional medicines, and systematically summarizes the effectiveness and mechanisms of probiotics, prebiotics, and postbiotics in maintaining health and treating diseases based on animal models and clinical trials. And based on current research outcomes and development trends in this field, the challenges and prospects of their clinical application in maintaining health, alleviating and treating diseases are analyzed. It is hoped to promote the application of probiotics, prebiotics, and postbiotics in disease treatment and open up new frontiers in probiotic research.

Potential Effects of Akkermansia Muciniphila in Aging and Aging-Related Diseases: Current Evidence and Perspectives

Akkermansia muciniphila (A. muciniphila) is an anaerobic bacterium that widely colonizes the mucus layer of the human and animal gut. The role of this symbiotic bacterium in host metabolism, inflammation, and cancer immunotherapy has been extensively investigated over the past 20 years. Recently, a growing number of studies have revealed a link between A. muciniphila, and aging and aging-related diseases (ARDs). Research in this area is gradually shifting from correlation analysis to exploration of causal relationships. Here, we systematically reviewed the association of A. muciniphila with aging and ARDs (including vascular degeneration, neurodegenerative diseases, osteoporosis, chronic kidney disease, and type 2 diabetes). Furthermore, we summarize the potential mechanisms of action of A. muciniphila and offer perspectives for future studies.

Translocation of gut microbes to epididymal white adipose tissue drives lipid metabolism disorder under heat stress

Heat stress induces multi-organ damage and serious physiological dysfunction in mammals, and gut bacteria may translocate to extra-intestinal tissues under heat stress pathology. However, whether gut bacteria translocate to the key metabolic organs and impair function as a result of heat stress remains unknown. Using a heat stress-induced mouse model, heat stress inhibited epididymal white adipose tissue (eWAT) expansion and induced lipid metabolic disorder but did not damage other organs, such as the heart, liver, spleen, or muscle. Microbial profiling analysis revealed that heat stress shifted the bacterial community in the cecum and eWAT but not in the inguinal white adipose tissue, blood, heart, liver, spleen, or muscle. Notably, gut-vascular barrier function was impaired, and the levels of some bacteria, particularly Lactobacillus, were higher in the eWAT, as confirmed by catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH) staining when mice were under heat stress. Moreover, integrated multi-omics analysis showed that the eWAT microbiota was associated with host lipid metabolism, and the expression of genes involved in the lipid metabolism in eWAT was upregulated under heat stress. A follow-up microbial supplementation study after introducing Lactobacillus plantarum to heat-stressed mice revealed that the probiotic ameliorated heat stress-induced loss of eWAT and dyslipidemia and reduced gut bacterial translocation to the eWAT by improving gut barrier function. Overall, our findings suggest that gut bacteria, particularly Lactobacillus spp., play a crucial role in heat stress-induced lipid metabolism disorder and that there is therapeutic potential for using probiotics, such as Lactobacillus plantarum.

Surgery-induced gut microbial dysbiosis promotes cognitive impairment via regulation of intestinal function and the metabolite palmitic amide

BACKGROUND

Perioperative neurocognitive disorders (PND) are the most common postoperative complications with few therapeutic options. Gut microbial dysbiosis is associated with neurological diseases; however, the mechanisms by which the microbiota regulates postoperative gastrointestinal and cognitive function are incompletely understood.

METHODS

Behavioral testing, MiSeq 16S rRNA gene sequencing, non-target metabolism, intestinal permeability detection, protein assays, and immunofluorescence staining were employed to discern the impacts of surgery on microbial profiles, intestinal barriers, serum metabolism, and the brain. Interventions in mice included fecal microbiota transplantation, the anti-inflammatory agent dexamethasone, Lactobacillus supplementation, indole propionic acid supplementation, and palmitic amide administration.

RESULTS

Surgery-induced cognitive impairment occurs predominantly in aged mice, and surgery-induced alterations in the microbiota composition profile exacerbate intestinal barrier disruption in aged mice. These adverse effects can be mitigated by transferring microbiota from young donors or by bolstering the intestinal barrier function using dexamethasone, Lactobacillus, or indole propionic acid. Moreover, microbiota composition profiles can be restored by transplanting feces from young mice to aged surgical mice, improving neuropathology and cognitive function, and these effects coincide with increased intestinal permeability. Metabolomic screening identified alterations in metabolites in mouse serum after surgery, especially the increase in palmitic amide. Palmitic amide levels in serum and brain can be decreased by transplanting feces from young mice to aged surgical mice. Oral palmitic amide exacerbates cognitive impairment and neuropathological changes in mice.

CONCLUSIONS

Gut microbial dysbiosis in mice after surgery is a key mechanism leading to cognition dysfunction, which disrupts the intestinal barrier and metabolic abnormalities, resulting in neuroinflammation and dendritic spine loss. Intestinal barrier damage and high level of palmitic amide in old mice may be the cause of high incidence of PND in the elderly. Preoperative microbiota regulation and intestinal barrier restoration may be of therapeutic benefit in preventing PND. Video Abstract.

Effects of gut microbiota on prostatic cancer: a two-sample Mendelian randomization study

Aim

Recent observational and small-sample case-control studies have shown a relationship between gut microbiota composition and prostatic cancer (PCa). Nevertheless, the causal association between gut microbiota and PCa is still unclear. Herein, we used the Mendelian randomization (MR) method to explore the potential causal relationship between gut microbiota and PCa.

Methods

In this two-sample MR study, data were extracted from the summary statistics of gut microbiota from the largest available genome-wide association study meta-analysis conducted by the MiBioGen consortium (n = 14,306) and the Dutch Microbiome Project (n = 8,208). Summary statistics for PCa were obtained from the FinnGen consortium release data (n = 95,213). Inverse variance weighted (IVW), MR-Egger, strength test (F), and MR-PRESSO were used to examine the potential causal association between gut microbiota and PCa. Cochran's Q statistics were used to quantify the heterogeneity of instrumental variables.

Results

IVW estimates suggested that the relative abundance of Akkermansia muciniphila (odds ratio [OR] = 0.7926, 95% confidence interval [CI]: 0.6655-0.9440) and Bacteroides salyersiae (OR = 0.9023, 95% CI: 0.8262-0.9853) were negatively associated with the odds of PCa, while that of Eubacterium biforme (OR = 1.1629, 95% CI: 1.0110-1.3376) was positively associated with the odds of PCa. In addition, we explored these relationships among patients without other cancers and similarly found that the relative abundance of Akkermansia muciniphila, Bacteroides salyersiae, and Eubacterium biforme were linked to PCa (all P < 0.05).

Conclusion

Gut microbiota potentially influenced the occurrence of PCa. Our findings may provide some new ideas for researching the methods of PCa prevention. In addition, further studies are needed to explore the causal association and specific underlying mechanisms between gut microbiota and PCa.