Clostridium butyricum modulates gut microbiota and reduces colitis associated colon cancer in mice

Clostridium butyricum Regulates the Inflammatory and Immunoregulatory Pathway Through NFKB1 in Colorectal Cancer Treatment

Colorectal cancer (CRC) ranks among the top three most prevalent malignancies globally and is a leading cause of cancer-related mortality. Traditional therapeutic approaches usually cause significant adverse effects, highlighting the urgent demand for alternative, more effective treatments. Probiotics have gained attentions as potential cancer therapy due to their beneficial impacts on host health. Clostridium butyricum (Cl. butyricum) has shown anticancer properties in recent studies, though the underlying mechanisms remain inadequately understood. This study presents an integrative analysis of network pharmacology and proteomics to elucidate the key targets of Cl. butyricum in CRC treatment. The network pharmacology analysis identified 72 overlapping genes, and functional analysis of these genes indicated that most pathways were related to pathways in cancer and inflammation, and butyrate emerging as the pivotal product of Cl. butyricum due to its strong associations with the identified hub genes. In parallel, proteomics analysis revealed 168 differential expressed proteins (DEPs) in Cl. butyricum-treated HCT-116 cells, comprising 78 upregulated and 90 downregulated proteins. These DEPs were primarily enriched in apoptosis and inflammatory pathways. PPI analysis further highlighted NFKB1 as key contributors to the anticancer effects of Cl. butyricum. The integrative analysis revealed a significant convergence of pathways enrichment patterns, particularly in inflammatory and immune-related pathways. Computational and experimental validation identified NFKB1 as a pivotal molecular target in CRC intervention. These collective findings elucidate the mechanistic basis of the antitumor properties of Cl. butyricum, highlighting its regulatory effects on NFKB1 through both inflammatory and, to a lesser extent, immunoregulatory pathways.

Protective effects of carboxymethyl chitosan-dialdehyde glucan/polydopamine carrier-delivered Bacillus subtilis on the intestinal tract of mice infected with Salmonella

This study investigated the protective effects of carboxymethyl chitosan-dialdehyde glucan/polydopamine carrier-delivered Bacillus subtilis (PBS) on Salmonella-induced intestinal inflammation in mice. The results indicated that PBS significantly lowered the organ index and inflammatory factor levels while increasing the levels of oxidase in mice. Interestingly, after PBS intervention, the mRNA expression levels of mucin, tight junction proteins, immune proteins, and transcription factors that constitute the intestinal barrier in mice exhibited a significant increase compared to those in the model group. The intestinal flora results showed that PBS improved the abundance of Ruminococcus, Bacillus, and Roseburia, simultaneously increasing the content of short-chain fatty acids. Furthermore, the downstream protein expression of pathway genes confirmed that PBS inhibited the inflammatory response by regulating the TLR4-NF-κB-NLRP3 inflammasome signaling pathway. These results indicate that carrier protection for Bacillus subtilis can enhance its relief effect on mice infected with Salmonella.

Probiotic effects of Clostridium cellabutyricum YQ-FP-027T on DSS-induced colitis mice via modulating gut microbiota and preventing inflammation

Butyrate-producing Clostridium spp. play fundamental roles in maintaining gut microbiota homeostasis by producing short-chain fatty acids. However, exploration of the strain resources and their probiotic effects remains limited. In previous work, a novel species of butyrate-producing Clostridium, Clostridium cellabutyricum YQ-FP-027T, was isolated from the pit mud of Chinese Baijiu brewing, which possesses antibacterial activities by modulating gut microbiota. The present study investigated the probiotic effects of YQ-FP-027T on mice with dextran sulfate sodium (DSS)-induced colitis and the underlying mechanism. The results showed that the mice treated with YQ-FP-027T exhibited lower disease activity index (DAI), recovered weight loss, and reduced colon shortening. Regarding gut microbial composition, these mice showed increased Shannon and Species richness observed (Sobs) indexes and a rising abundance of beneficial bacteria such as Akkermansia and Alistipes. Additionally, the expression levels of inflammatory factors Interleukin-1 beta (IL-1β), Interleukin-6 (IL-6), and Tumor Necrosis Factor-alpha (TNF-α) were suppressed, while those of anti-inflammatory factor Interleukin-10 (IL-10) and the cathelicidin-related antimicrobial peptide (CRAMP) were enhanced under YQ-FP-027T treatment. These results suggest that YQ-FP-027T holds potential as a promising probiotic against DSS-induced colitis via optimizing gut microbial community structure and modulating gut immune microenvironment.

Bifidobacterium longum subsp. longum XZ01 delays the progression of colon cancer in mice through the interaction between the microbial spatial distribution and tumour immunity

Studies have shown that the colonisation of active microorganisms is more conducive to the development of tumour immunotherapy, but intuitive evidence regarding shaping of the tumour immune microenvironment is lacking. In this study, we used Bifidobacterium longum subsp. longum (XZ01) to intervene in a colon cancer mouse model and found that its mechanism may be related to the interaction between the spatial distribution of microorganisms and tumour immunity. Through the visualisation method we established, for the first time, we showed that harmful active bacteria such as Streptococcus and Rhodococcus specifically accumulate in the middle and upper layers of tumour tissue. These bacteria likely participate in signalling pathways that affect macrophages by directly contacting or invading the macrophages, leading to a nondifferentiated state in macrophages and the loss of some immune functions. Furthermore, the accumulation of Streptococcus and Rhodococcus fragments in the deep layer of tumour tissue likely upregulates the expression of IL-10 in tumour tissue and inhibits other immune cells, such as CD8+ T cells, DC and NK cells. In contrast, XZ01 can specifically compete for the growth sites of Streptococcus and Rhodococcus in the middle and upper layers of tumour tissue and probably protects macrophages from being invaded by harmful bacteria. XZ01 directly regulates the polarisation of M0 macrophages towards the M1 phenotype by upregulating IFN-γ, thus activating tumour immunity to inhibit the growth of tumour cells. This study revealed that the influence of active microorganisms on the tumour immune microenvironment is crucial for effective immunotherapy intervention, potentially offering new targets for improving patient prognosis.

Causal relationships of gut microbiota and blood metabolites with ovarian cancer and endometrial cancer: a Mendelian randomization study

OBJECTIVES

The study aimed to investigate the causal relationships of gut microbiota (GM), ovarian cancer (OC), endometrial cancer (EC), and potential metabolite mediators using Mendelian randomization (MR) analysis.

METHODS

Bidirectional two-sample MR analysis and reverse MR analysis of GM on OC/EC were employed to determine the causal effects of GM on OC/EC and the mediating role of blood metabolites in the relationship between GM and OC/EC, with results validated through sensitivity analysis.

RESULTS

We identified 6 pathogenic bacterial taxa associated with OC, including Euryarchaeota, Escherichia-Shigella, FamilyXIIIAD3011group, Prevotella9, and two unknown genera. Christensenellaceae R.7group, Tyzzerella3, and Victivallaceae were found to be protective against OC. The increase in EC risk was positively associated with Erysipelotrichia, Erysipelotrichaceae, Erysipelotrichales, and FamilyXI. Dorea, RuminococcaceaeUCG014, and Turicibacter exhibited a negative correlation with the EC risk. A total of 26 and 19 blood metabolites related to GM were identified, showing significant correlations with OC and EC, respectively. Cytosine was found to be an intermediate metabolite greatly associated with EC and FamilyXI. In reverse MR analysis, the FamilyXIIIAD3011group exhibited a significant bidirectional causal relationship with OC.

CONCLUSION

Our study revealed causal relationships of GM and intermediate metabolites with OC/EC, providing new avenues for understanding OC/EC and developing effective treatment strategies.

The combination of Clostridium butyricum and Akkermansia muciniphila mitigates DSS-induced colitis and attenuates colitis-associated tumorigenesis by modulating gut microbiota and reducing CD8+ T cells in mice

The gut microbiota is closely associated with inflammatory bowel disease (IBD) and colorectal cancer (CRC). Probiotics such as Clostridium butyricum (CB) or Akkermansia muciniphila (AKK) have the potential to treat inflammatory bowel disease (IBD) or colorectal cancer (CRC). However, research on the combined therapeutic effects and immunomodulatory mechanisms of CB and AKK in treating IBD or CRC has never been studied. This study evaluates the potential of co-administration of CB and AKK in treating DSS/AOM-induced IBD and colitis-associated CRC. Our results indicate that compared to mono-administration, the co-administration of CB and AKK not only significantly alleviates symptoms such as weight loss, colon shortening, and increased Disease Activity Index in IBD mice but also regulates the gut microbiota composition and effectively suppresses colonic inflammatory responses. In the colitis-associated CRC mice model, a combination of CB and AKK significantly alleviates weight loss and markedly reduces inflammatory infiltration of macrophages and cytotoxic T lymphocytes (CTLs) in the colon, thereby regulating anti-tumor immunity and inhibiting the occurrence of inflammation-induced CRC. In addition, we found that the combined probiotic therapy of CB and AKK can enhance the sensitivity of colitis-associated CRC mice to the immune checkpoint inhibitor anti-mouse PD-L1 (aPD-L1), significantly improving the anti-tumor efficacy of immunotherapy and the survival rate of colitis-associated CRC mice. Furthermore, fecal microbiota transplantation therapy showed that transplanting feces from CRC mice treated with the co-administration of CB and AKK into other CRC mice alleviated the tumor loads in the colon and significantly extended their survival rate. Our study suggests that the combined use of two probiotics, CB and AKK, can not only alleviate chronic intestinal inflammation but also inhibit the progression to CRC. This may be a natural and relatively safe method to support the gut microbiota and enhance the host's immunity against cancer.

IMPORTANCE

Our study suggests that the combined administration of CB and AKK probiotics, as opposed to a single probiotic strain, holds considerable promise in preventing the advancement of IBD to CRC. This synergistic effect is attributed to the ability of this probiotic combination to more effectively modulate the gut microbiota, curb inflammatory reactions, bolster the efficacy of immunotherapeutic approaches, and optimize treatment results via fecal microbiota transplantation.

Sodium butyrate regulates macrophage polarization by TGR5/β-arrestin2 in vitro

BACKGROUND

Macrophages play an important role in the pathogenesis of ulcerative colitis (UC). We will explore the effects of sodium butyrate (SB) on macrophage function.

METHODS

The targets of butyric acid were identified using SwissTargetPrediction database and surface plasmon resonance (SPR). Limited proteolysis mass spectrometry (Lip-MS) was used to further investigate the binding sites of butyric acid with its targets and molecular docking was employed to simulate their binding modes. Macrophage polarization model was established with lipopolysaccharide (LPS) in vitro. Takeda G protein-coupled receptor 5 (TGR5) and β-arrestin2 expression and macrophage polarization markers were detected with or without SB.

RESULTS

TGR5 was identified as the target of butyric acid. Moreover, the amino acid regions 275-286 and 321-330 of TGR5 (GPBAR1 [275-286] and GPBAR1 [321-330]) were the potential binding regions for butyric acid. Based on molecular docking analysis, butyric acid formed effective hydrogen-bonding interactions with ASP-284 and TYR-287 of TGR5. In cell experiments, LPS inhibited the expression of TGR5, β-arrestin2, IL-10, ARG1, and CD206 and increased the expression of IL-1β, iNOS, and CD86, while SB reversed the effect of LPS. SBI-115, a TGR5 antagonist, and knockdown of β-arrestin2 inhibited the effect of sodium butyrate. INT-777, a TGR5 agonist, reversed the inhibitory effect of knockdown of β-arrestin2.

CONCLUSION

SB inhibited M1-like polarization and promoted M2-like polarization induced by LPS via TGR5/β-arrestin2 in RAW264.7 cells and TGR5 was the target of SB.

Research progress on anti-inflammatory drugs for preventing colitis-associated colorectal cancer

Colorectal cancer (CRC) is the third most prevalent malignancy worldwide. Inflammatory bowel diseases (IBD) encompass a group of chronic intestinal inflammatory disorders, including ulcerative colitis (UC) and Crohn's disease (CD). As a chronic inflammatory bowel disease, UC may persist and elevate the risk of malignancy, thereby contributing to the development of colorectal cancer, known as colitis-associated colorectal cancer (CAC). Chronic intestinal inflammation is a significant risk factor for colorectal cancer, and the incidence of colitis-associated colorectal cancer continues to rise. Current studies indicate that therapeutic agents targeting inflammation and key molecules or signaling pathways involved in the inflammatory process may effectively prevent and treat CAC. Mechanistically, drugs with anti-inflammatory or modulatory effects on inflammation-related pathways may exert preventive or therapeutic roles in CAC through multiple molecules or signaling pathways implicated in tumor development. Moreover, the development or discovery of novel drugs with anti-inflammatory properties to prevent or delay CAC progression is becoming an emerging field in fighting against CRC. Therefore, this review aims to summarize drugs that prevent or delay CAC through modulating anti-inflammatory pathways. First, we categorize the published studies exploring the role of anti-inflammatory in CAC prevention. Second, we highlight the specific molecular mechanisms underlying the anti-inflammatory effect of the above-mentioned drugs. Finally, we discuss the potential and challenges associated with clinical application of these drugs. It is hoped that this review offers new insights for further drug development and mechanism exploration.

Beneficial microbiome and diet interplay in early-onset colorectal cancer

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second leading cause of cancer-related deaths worldwide. Although the risk of developing CRC increases with age, approximately 10% of newly diagnosed cases occur in individuals under the age of 50. Significant changes in dietary habits in young adults since industrialization create a favorable microenvironment for colorectal carcinogenesis. We aim here to shed light on the complex interplay between diet and gut microbiome in the pathogenesis and prevention of early-onset CRC (EO-CRC). We provide an overview of dietary risk factors associated with EO-CRC and contrast them with the general trends for CRC. We delve into gut bacteria, fungi, and phages with potential benefits against CRC and discuss the underlying molecular mechanisms. Furthermore, based on recent findings from human studies, we offer insights into how dietary modifications could potentially enhance gut microbiome composition to mitigate CRC risk. All together, we outline the current research landscape in this area and propose directions for future investigations that could pave the way for novel preventive and therapeutic strategies.

Clostridium butyricum, a future star in sepsis treatment

Sepsis is a systemic inflammatory response syndrome of multiorgan failure caused by dysregulation of the host response to infection and is a major cause of death in critically ill patients. In recent years, with the continuous development of sequencing technology, the intestinal microecology of this disease has been increasingly studied. The gut microbiota plays a host-protective role mainly through the maintenance of normal immune function and the intestinal barrier. Recent evidence suggests that intestinal flora dysbiosis plays a crucial role in sepsis. Clostridium butyricum (C. butyricum), which has been used as a probiotic in poultry feed since its discovery, has been found to play a potential protective role in intestinal infections, inflammatory bowel disease (IBD), colorectal cancer, and other diseases in recent studies. In this review, we continue to focus on the important role and mechanism of C. butyricum as a probiotic in human diseases, especially intestinal diseases. Additionally, we evaluate the research progress of C. butyricum in treatment of sepsis to identify more therapeutic targets for the clinical treatment of sepsis.

Targeting the gut microbiota: a new strategy for colorectal cancer treatment

BACKGROUND

How to reduce the high incidence rate and mortality of colorectal cancer (CRC) effectively is the focus of current research. Endoscopic treatment of early-stage CRC and colorectal adenomas (CAC) has a high success rate, but although several treatments are available for advanced CRC, such as surgery, radiotherapy, chemotherapy, and immunotherapy, the 5-year survival rate remains low. In view of the high incidence rate and mortality of CRC, early rational drug prevention for high-risk groups and exploration of alternative treatment modalities are particularly warranted. Gut microbiota is the target of and interacts with probiotics, prebiotics, aspirin, metformin, and various Chinese herbal medicines (CHMs) for the prevention of CRC. In addition, the anti-cancer mechanisms of probiotics differ widely among bacterial strains, and both bacterial strains and their derivatives and metabolites have been found to have anti-cancer effects. Gut microbiota plays a significant role in early drug prevention of CRC and treatment of CRC in its middle and late stages, targeting gut microbiota may be a new strategy for colorectal cancer treatment.

Transformation of colitis and colorectal cancer: a tale of gut microbiota

Intestinal inflammation modifies host physiology to promote the occurrence of colorectal cancer (CRC), as seen in colitis-associated CRC. Gut microbiota is crucial in cancer progression, primarily by inducing intestinal chronic inflammatory microenvironment, leading to DNA damage, chromosomal mutation, and alterations in specific metabolite production. Therefore, there is an increasing interest in microbiota-based prevention and treatment strategies, such as probiotics, prebiotics, microbiota-derived metabolites, and fecal microbiota transplantation. This review aims to provide valuable insights into the potential correlations between gut microbiota and colitis-associated CRC, as well as the promising microbiota-based strategies for colitis-associated CRC.

Immunomodulation aspects of gut microbiome-related interventional strategies in colorectal cancer

Colorectal cancer (CRC), the third most common cancer worldwide, develops mainly due to the accumulation of genetic and epigenetic changes over many years. Substantial evidence suggests that gut microbiota plays a significant role in the initiation, progression, and control of CRC, depending on the balance between beneficial and pathogenic microorganisms. Nonetheless, gut microbiota composition by regulating the host immune response may either promote or inhibit CRC. Thus, modification of gut microbiota potentially impacts clinical outcomes of immunotherapy. Previous studies have indicated that therapeutic strategies such as probiotics, prebiotics, and postbiotics enhance the intestinal immune system and improve the efficacy of immunotherapeutic agents, potentially serving as a complementary strategy in cancer immunotherapy. This review discusses the role of the gut microbiota in the onset and development of CRC in relation to the immune response. Additionally, we focus on the effect of strategies manipulating gut microbiome on the immune response and efficacy of immunotherapy against CRC. We demonstrate that manipulation of gut microbiome can enhance immune response and outcomes of immunotherapy through downregulating Treg cells and other immunosuppressive cells while improving the function of T cells within the tumor; however, further research, especially clinical trials, are needed to evaluate its efficacy in cancer treatment.

Antioxidant Role of Probiotics in Inflammation-Induced Colorectal Cancer

Colorectal cancer (CRC) continues to be a significant contributor to global morbidity and mortality. Emerging evidence indicates that disturbances in gut microbial composition, the formation of reactive oxygen species (ROS), and the resulting inflammation can lead to DNA damage, driving the pathogenesis and progression of CRC. Notably, bacterial metabolites can either protect against or contribute to oxidative stress by modulating the activity of antioxidant enzymes and influencing signaling pathways that govern ROS-induced inflammation. Additionally, microbiota byproducts, when supplemented through probiotics, can affect tumor microenvironments to enhance treatment efficacy and selectively mediate the ROS-induced destruction of CRC cells. This review aims to discuss the mechanisms by which taxonomical shifts in gut microbiota and related metabolites such as short-chain fatty acids, secondary bile acids, and trimethylamine-N-oxide influence ROS concentrations to safeguard or promote the onset of inflammation-mediated CRC. Additionally, we focus on the role of probiotic species in modulating ROS-mediated signaling pathways that influence both oxidative status and inflammation, such as Nrf2-Keap1, NF-κB, and NLRP3 to mitigate carcinogenesis. Overall, a deeper understanding of the role of gut microbiota on oxidative stress may aid in delaying or preventing the onset of CRC and offer new avenues for adjunct, CRC-specific therapeutic interventions such as cancer immunotherapy.

Bifidobacterium bifidum Ameliorates DSS-Induced Colitis in Mice by Regulating Microbial Metabolome and Targeting Gut Microbiota

Inflammatory bowel disease (IBD) is a recurrent inflammatory condition affecting the gastrointestinal tract, and its clinical treatment remains suboptimal. Probiotics have shown effectiveness in alleviating dextran sulfate sodium salt (DSS)-induced colitis, exhibiting strain-specific anti-inflammatory properties. In this study, we compared the therapeutic effects of five strains of Bifidobacterium bifidum isolated from healthy adult feces on DSS-induced colitis in mice. Additionally, we investigated the underlying mechanisms by examining gut microbiota composition and microbial metabolome. Our findings highlighted the superior efficacy of B. bifidum M1-3 compared to other strains. It significantly improved colitis symptoms, mitigated gut barrier disruption, and reduced colonic inflammation in DSS-treated mice. Moreover, gut microbiota composition analysis revealed that B. bifidum M1-3 treatment increased the abundance and diversity of gut microbiota. Specifically, it significantly increased the abundance of Muribaculaceae, Lactobacillus, Bacteroides, and Enterorhabdus, while decreasing the abundance of Escherichia-Shigella. Furthermore, our nontargeted metabolomics analysis illustrated that B. bifidum M1-3 treatment had a regulatory effect on various metabolic pathways, including tyrosine metabolism, lysine degradation, and tryptophan metabolism. Importantly, we confirmed that the therapeutic efficiency of B. bifidum M1-3 was dependent on the gut microbiota. These results are conducive to the development of probiotic products for alleviating colitis.

Engineered bacteria in tumor immunotherapy

As the limitations of cancer immunotherapy become increasingly apparent, there is considerable anticipation regarding the utilization of biological tools to enhance treatment efficacy, particularly bacteria and their derivatives. Leveraging advances in genetic and synthetic biology technologies, engineered bacteria now play important roles far beyond those of conventional immunoregulatory agents, and they could function as tumor-targeting vehicles and in situ pharmaceutical factories. In recent years, these engineered bacteria play a role in almost every aspect of immunotherapy. It is nothing short of impressive to keep seeing different strain of bacteria modified in diverse ways for unique immunological enhancement. In this review, we have scrutinized the intricate interplay between the immune system and these engineered bacteria. These interactions generate strategies that can directly or indirectly optimize immunotherapy and even modulate the effects of combination therapies. Collectively, these engineered bacteria present a promising novel therapeutic strategy that promises to change the current landscape of immunotherapy.

Clostridium butyricum isolated from giant panda can attenuate dextran sodium sulfate-induced colitis in mice

Objective

Probiotics are beneficial to the intestinal barrier, but few studies have investigated probiotics from giant pandas. This study aims to explore the preventive effects of giant panda-derived Clostridium butyricum on dextran sodium sulfate (DSS)-induced colitis in mice.

Methods

Clostridium butyricum was administered to mice 14 days before administering DSS treatment to induce enteritis.

Results

Clostridium butyricum B14 could more effectively prevent colitis in mice than C. butyricum B13. C. butyricum B14 protected the mouse colon by decreasing the histology index and serum interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) levels, which improved intestinal inflammation-related symptoms. In addition, the treatment led to the regulation of the expression of Tifa, Igkv12-89, and Nr1d1, which in turn inhibited immune pathways. The expression of Muc4, Lama3, Cldn4, Cldn3, Ocln, Zo1, Zo2, and Snai is related the intestinal mucosal barrier. 16S sequencing shows that the C. butyricum B14 significantly increased the abundance of certain intestinal probiotics. Overall, C. butyricum B14 exerted a preventive effect on colitis in mice by inhibiting immune responses, enhancing the intestinal barrier and increasing the abundance of probiotic species. Thus, C. butyricum B14 administration helps regulate the balance of the intestinal microecology. It can suppress immune pathways and enhance barrier-protective proteins.

Fabrication of zein-tamarind seed polysaccharide-curcumin nanocomplexes: their characterization and impact on alleviating colitis and gut microbiota dysbiosis in mice

In this work, a zein-tamarind seed polysaccharide (TSP) co-delivery system was fabricated using an anti-solvent precipitation method. The formation mechanism, characterization, and effect on alleviating colitis and gut microbiota dysbiosis in mice of zein-TSP-curcumin (Z/T-Cur) nanocomplexes were investigated. Hydrogen bonding and the hydrophobic effect played a key role in the formation of Z/T-Cur nanocomplexes, and the interactions were spontaneous and driven by enthalpy. The encapsulation efficiency, loading capacity, and bioavailability increased from 60.8% (Zein-Cur) to 91.7% (Z/T-Cur1:1), from 6.1% (Zein-Cur) to 18.3% (Z/T-Cur1:1), and from 4.7% (Zein-Cur) to 20.0% (Z/T-Cur1:1), respectively. The Z/T-Cur significantly alleviated colitis symptoms in DSS-treated mice. Additionally, the prepared nanocomplexes rebalanced the gut microbiota composition of colitis mice by increasing the abundance of Akkermansia. Odoribacter and Monoglobus were rich in the Z-T-Cur treatment group, and Turicibacter and Bifidobacterium were rich in the zein-TSP treatment group. This study demonstrated that the TSP could be helpful in the targeted drug delivery system.

The Potential of Clostridium butyricum to Preserve Gut Health, and to Mitigate Non-AIDS Comorbidities in People Living with HIV

A dramatic reduction in mortality among people living with HIV (PLWH) has been achieved during the modern antiretroviral therapy (ART) era. However, ART does not restore gut barrier function even after long-term viral suppression, allowing microbial products to enter the systemic blood circulation and induce chronic immune activation. In PLWH, a chronic state of systemic inflammation exists and persists, which increases the risk of development of inflammation-associated non-AIDS comorbidities such as metabolic disorders, cardiovascular diseases, and cancer. Clostridium butyricum is a human butyrate-producing symbiont present in the gut microbiome. Convergent evidence has demonstrated favorable effects of C. butyricum for gastrointestinal health, including maintenance of the structural and functional integrity of the gut barrier, inhibition of pathogenic bacteria within the intestine, and reduction of microbial translocation. Moreover, C. butyricum supplementation has been observed to have a positive effect on various inflammation-related diseases such as diabetes, ulcerative colitis, and cancer, which are also recognized as non-AIDS comorbidities associated with epithelial gut damage. There is currently scant published research in the literature, focusing on the influence of C. butyricum in the gut of PLWH. In this hypothesis review, we speculate the use of C. butyricum as a probiotic oral supplementation may well emerge as a potential future synergistic adjunctive strategy in PLWH, in tandem with ART, to restore and consolidate intestinal barrier integrity, repair the leaky gut, prevent microbial translocation from the gut, and reduce both gut and systemic inflammation, with the ultimate objective of decreasing the risk for development of non-AIDS comorbidities in PLWH.

Overcoming cancer risk in inflammatory bowel disease: new insights into preventive strategies and pathogenesis mechanisms including interactions of immune cells, cancer signaling pathways, and gut microbiota

Inflammatory bowel disease (IBD), characterized primarily by gastrointestinal inflammation, predominantly manifests as Crohn's disease (CD) and ulcerative colitis (UC). It is acknowledged that Inflammation plays a significant role in cancer development and patients with IBD have an increased risk of various cancers. The progression from inflammation to carcinogenesis in IBD is a result of the interplay between immune cells, gut microbiota, and carcinogenic signaling pathways in epithelial cells. Long-term chronic inflammation can lead to the accumulation of mutations in epithelial cells and the abnormal activation of carcinogenic signaling pathways. Furthermore, Immune cells play a pivotal role in both the acute and chronic phases of IBD, contributing to the transformation from inflammation to tumorigenesis. And patients with IBD frequently exhibit dysbiosis of the intestinal microbiome. Disruption of the gut microbiota and subsequent immune dysregulation are central to the pathogenesis of both IBD and colitis associated colorectal cancer (CAC). The proactive management of inflammation combined with regular endoscopic and tumor screenings represents the most direct and effective strategy to prevent the IBD-associated cancer.

Probiotics intervention in colorectal cancer: From traditional approaches to novel strategies

ABSTRACT

The intestine harbors a large population of microorganisms that interact with epithelial cells to maintain host healthy physiological status. These intestinal microbiota engage in the fermentation of non-digestible nutrients and produce beneficial metabolites to regulate host homeostasis, metabolism, and immune response. The disruption of microbiota, known as dysbiosis, has been implicated in many intestinal diseases, including colorectal cancer (CRC). As the third most common cancer and the second leading cause of cancer-related death worldwide, CRC poses a significant health burden. There is an urgent need for novel interventions to reduce CRC incidence and improve clinical outcomes. Modulating the intestinal microbiota has emerged as a promising approach for CRC prevention and treatment. Current research efforts in CRC probiotics primarily focus on reducing the incidence of CRC, alleviating treatment-related side effects, and potentiating the efficacy of anticancer therapy, which is the key to successful translation to clinical practice. This paper aims to review the traditional probiotics and new interventions, such as next-generation probiotics and postbiotics, in the context of CRC. The underlying mechanisms of probiotic anti-cancer effects are also discussed, including the restoration of microbial composition, reinforcement of gut barrier integrity, induction of cancer cell apoptosis, inactivation of carcinogens, and modulation of host immune response. This paper further evaluates the novel strategy of probiotics as an adjuvant therapy in boosting the efficacy of chemotherapy and immunotherapy. Despite all the promising findings presented in studies, the evaluation of potential risks, optimization of delivery methods, and consideration of intra-patient variability of gut microbial baseline must be thoroughly interpreted before bench-to-bedside translation.

Effect of the Combination of Clostridium butyricum and Mycelium of Phellinus igniarius on Intestinal Microbiota and Serum Metabolites in DSS-Induced Colitis

Clostridium butyricum (CB) and Phellinus igniarius (PI) have anti-inflammatory, immune regulation, anti-tumor, and other functions. This study aimed to explore the therapeutic effect of CB and mycelium of PI (MPI) alone and in combination on colitis mice induced by dextran sodium sulfate (DSS). Mice were randomly assigned to five groups: (1) control (CTRL), (2) DSS, (3) CB, (4) MPI, and (5) CB + MPI (CON). The weight of the mice was recorded daily during the experiment, and the length of the colon was measured on the last day of the experiment. The colons were collected for hematoxylin and eosin staining, colon contents were collected for intestinal flora analysis, and serum was collected for metabolite analysis. The results showed that compared with the DSS group, CB, MPI, and CON treatments inhibited the weight loss and colon length shortening caused by DSS, significantly increased the concentrations of interleukin (IL)-4, IL-10, and superoxide dismutase, and significantly decreased the concentrations of IL-6, tumor necrosis factor-α, and myeloperoxidase. Gene sequence analysis of 16S rRNA showed that CB, MPI, and CON treatments changed the composition and structure of intestinal microorganisms. Metabolome results showed that CB, MPI, and CON treatments changed serum metabolites in DSS-treated mice, including dodecenoylcarnitine, L-urobilinogen, and citric acid. In conclusion, CB, MPI, and CON treatments alleviated DSS-induced colitis in mice by regulating intestinal flora and metabolites, with the CON group having the best effect.

Probiotic Clostridium butyricum ameliorates cognitive impairment in obesity via the microbiota-gut-brain axis

Obesity is a risk factor for cognitive dysfunction and neurodegenerative disease, including Alzheimer's disease (AD). The gut microbiota-brain axis is altered in obesity and linked to cognitive impairment and neurodegenerative disorders. Here, we targeted obesity-induced cognitive impairment by testing the impact of the probiotic Clostridium butyricum, which has previously shown beneficial effects on gut homeostasis and brain function. Firstly, we characterized and analyzed the gut microbial profiles of participants with obesity and the correlation between gut microbiota and cognitive scores. Then, using an obese mouse model induced by a Western-style diet (high-fat and fiber-deficient diet), the effects of Clostridium butyricum on the microbiota-gut-brain axis and hippocampal cognitive function were evaluated. Finally, fecal microbiota transplantation was performed to assess the functional link between Clostridium butyricum remodeling gut microbiota and hippocampal synaptic protein and cognitive behaviors. Our results showed that participants with obesity had gut microbiota dysbiosis characterized by an increase in phylum Proteobacteria and a decrease in Clostridium butyricum, which were closely associated with cognitive decline. In diet-induced obese mice, oral Clostridium butyricum supplementation significantly alleviated cognitive impairment, attenuated the deficit of hippocampal neurite outgrowth and synaptic ultrastructure, improved hippocampal transcriptome related to synapses and dendrites; a comparison of the effects of Clostridium butyricum in mice against human AD datasets revealed that many of the genes changes in AD were reversed by Clostridium butyricum; concurrently, Clostridium butyricum also prevented gut microbiota dysbiosis, colonic barrier impairment and inflammation, and attenuated endotoxemia. Importantly, fecal microbiota transplantation from donor-obese mice with Clostridium butyricum supplementation facilitated cognitive variables and colonic integrity compared with from donor obese mice, highlighting that Clostridium butyricum's impact on cognitive function is largely due to its ability to remodel gut microbiota. Our findings provide the first insights into the neuroprotective effects of Clostridium butyricum on obesity-associated cognitive impairments and neurodegeneration via the gut microbiota-gut-brain axis.

Advancements in Endoscopic Resection for Colitis-Associated Colorectal Neoplasia in Inflammatory Bowel Disease: Turning Visible into Resectable

Patients suffering from inflammatory bowel disease (IBD) face a two to three-fold higher risk of developing colorectal cancer (CRC) compared to the general population. In recent years, significant progress has been made in comprehending the natural history of IBD-associated CRC (IBD-CRC) and refining its treatment strategies. The decreased incidence of IBD-CRC can be attributed to improved therapeutic management of inflammation, advancements in endoscopy, and early detection of precancerous lesions via surveillance programs. Advanced imaging technologies have made previously undetectable dysplasia visible in most cases, allowing for a much more precise and detailed examination of the mucosa. Additionally, new tools have facilitated the endoscopic resection (ER) of visible lesions in IBD. Particularly, the key to effectively manage colitis-associated colorectal neoplasia (CAN) is to first identify it and subsequently guarantee a complete ER in order to avoid surgery and opt for continuing surveillance. Advanced ER techniques for CAN include endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and hybrid ESD-EMR (h-ESD). This narrative review aims to consolidate the current literature on IBD-CRC, providing an overview of advanced techniques for ER of CAN in IBD, with a particular emphasis on the impact of ESD on the long-term outcomes of IBD patients.

In vitro-simulated intestinal flora fermentation of Porphyra haitanensis polysaccharides obtained by different assisted extractions and their fermented products against HT-29 human colon cancer cells

Herein, we studied the in vitro-simulated intestinal flora fermentation of Porphyra haitanensis polysaccharides (PHPs) with microwave, ultrasonic, ultra-high pressure-assisted extraction and the protective effect of their fermented products against HT-29 human colon cancer cells. The results showed that PHPs were largely degraded at the 18 h stage of ascending colon fermentation, further greatly increasing the contents of reducing sugars and short-chain fatty acids (p < 0.05). Particularly, the PHPs subjected to ultra-high pressure-assisted extraction (UHP-PHP) showed the highest reducing sugar content of 1.68 ± 0.01 mg mL-1 and butyric acid content of 410.77 ± 7.99 mmol mL-1. Moreover, UHP-PHP showed a better effect in increasing the ratio of Bacteroidetes/Firmicutes and decreasing the abundance of Proteobacteria and Escherichia coli. PHPs could protect against HT-29 cells by increasing the ROS levels in a concentration-dependent manner, especially UHP-PHP fermented in a descending colon for 24 h. This was related to the up-regulated apoptosis-related genes (Bax and Bak), down-regulated protein expression of Bcl-2 and activation of the p-AKT protein, thereby promoting the apoptosis of HT-29 cells. Our results can facilitate the modification of PHPs and their practical application in the development of intestinal health improving products.

Microbiota in cancer: molecular mechanisms and therapeutic interventions

The diverse bacterial populations within the symbiotic microbiota play a pivotal role in both health and disease. Microbiota modulates critical aspects of tumor biology including cell proliferation, invasion, and metastasis. This regulation occurs through mechanisms like enhancing genomic damage, hindering gene repair, activating aberrant cell signaling pathways, influencing tumor cell metabolism, promoting revascularization, and remodeling the tumor immune microenvironment. These microbiota-mediated effects significantly impact overall survival and the recurrence of tumors after surgery by affecting the efficacy of chemoradiotherapy. Moreover, leveraging the microbiota for the development of biovectors, probiotics, prebiotics, and synbiotics, in addition to utilizing antibiotics, dietary adjustments, defensins, oncolytic virotherapy, and fecal microbiota transplantation, offers promising alternatives for cancer treatment. Nonetheless, due to the extensive and diverse nature of the microbiota, along with tumor heterogeneity, the molecular mechanisms underlying the role of microbiota in cancer remain a subject of intense debate. In this context, we refocus on various cancers, delving into the molecular signaling pathways associated with the microbiota and its derivatives, the reshaping of the tumor microenvironmental matrix, and the impact on tolerance to tumor treatments such as chemotherapy and radiotherapy. This exploration aims to shed light on novel perspectives and potential applications in the field.

A Novel Bifidobacterium/Klebsiella Ratio in Characterization Analysis of the Gut and Bile Microbiota of CCA Patients

Cholangiocarcinoma (CCA) is a serious health problem worldwide. The gut and bile microbiota have not been clearly characterized in patients with CCA, and better noninvasive diagnostic approaches for CCA need to be established. The aim of this study was to investigate the characteristics of the gut and bile microbiota in CCA patients. Forty-two CCA patients and 16 healthy normal controls (HNCs) were enrolled. DNA was extracted from fecal and bile samples and subjected to 16S rRNA gene analysis. We found that there were significant differences in the species diversity, structure, and composition of the microbial communities between the CCA group and the HNC grouAt the phylum level, compared with that in the HNC group, the relative abundance of Firmicutes and Actinobacteriota was significantly decreased in the CCA group, whereas Proteobacteria and Bacteroidota were significantly enriched. The Firmicutes/Bacteroidota (F/B) ratio significantly decreased in the CCA group compared to the HNC grouThe relative abundance of Klebsiella in the CCA group was significantly higher than that in the HNC group, while the relative abundance of Bifidobacterium was significantly decreased. The Bifidobacterium/Klebsiella (B/K) ratio was established as a novel biomarker and was found to be significantly decreased in the CCA group compared with the HNC grouOur findings provide evidence supporting the use of Klebsiella and Bifidobacterium as noninvasive intestinal microbiomarkers for improving the diagnosis of CCA.

Polystyrene may alter the cooperation mechanism of gut microbiota and immune system through co-exposure with DCBQ

The toxicity of Polystyrene (PS) may be higher through co-exposure with other pollutants. Human can simultaneously face the challenges from the various pollutants. Nevertheless, little research has been done on the combined effects of PS and 2,6-dichloro-p-benzoquinone (DCBQ) disinfection byproduct. Considering the potential risk of PS and DCBQ, we aimed to illustrate the effects of PS in combination with DCBQ on the immune responses of mice. We found that cotreatment of DCBQ and PS may inhibit the activity of spleen CD4+ T cells and interfere with the normal function of the immune system. Further research found that DCBQ + PS resulted in increasing amount of the inflammatory cells in intestine via histopathological evaluation. The reason might be that DCBQ + PS has changed the composition of intestinal flora, abnormally activated intestinal macrophage, and inhibited the expression of immune-related genes, thus leading to intestinal immune disorders and triggering intestinal inflammation. In summary, PS may alter the cooperation mechanism of gut microbiota and immune system through co-exposure with DCBQ. Current results suggested that more attention should be paid to the combined toxic effects of environmental contaminants.

The metagenomic and metabolomic profile of the gut microbes in Chinese full-term and late preterm infants treated with Clostridium butyricum

The present study investigated the composition, abundance, and diversity of gut microbes in full-term and late-preterm infants from a medical center in eastern China. A total of 144 genomes of stool samples were captured for 16S rRNA metagenomic analyses. A high abundance of commensal intestinal bacteria was detected in these samples such as Phocaeicola vulgatus, Escherichia coli, and Faecalibacterium prausnitzii, indicating a relatively consistent diversity of gut microbes in the present full-term infants aged 38-40 weeks. However, late preterm infants (n = 50) with mandatory antimicrobials feeding exhibited lower diversity but a higher composition of opportunistic pathogens such as Enterococcus species. Centralized on the situation, we explored the regulatory effect of Clostridium butyricum as probiotics on these late preterm infants. The consumption of C. butyricum did not restore the composition of gut microbes altered by antimicrobials to normal levels, although several opportunistic pathogens decreased significantly after probiotic therapy including Staphylococcus aureus, Sphingomonas echinoides, and Pseudomonas putida. We also compared the effects of day-fed versus night-fed probiotics. Intriguingly, the nighttime feeding showed a higher proportion of C. butyricum compared with probiotic day-feeding. Finally, fecal metabolome and metabolites were analyzed in late preterm infants with (n = 20) or without probiotic therapy (n = 20). The KEGG enrichment analysis demonstrated that vitamin digestion and absorption, synaptic vesicle cycle, and biotin metabolism were significantly increased in the probiotic-treated group, while MSEA indicated that a series of metabolism were significantly enriched in probiotic-treated infants including glycerolipid, biotin, and lysine, indicating the complex effects of probiotic therapy on glutathione metabolism and nutrients digestion and absorption in late preterm infants. Overall, this study provided metagenomic and metabolomic profile of the gut microbes in full-term newborns and late preterm infants in eastern China. Further studies are needed to support and elucidate the role of probiotic feeding in late preterm infants with mandatory antimicrobial treatment.

Genome Analysis and Optimization of Caproic Acid Production of Clostridium butyricum GD1-1 Isolated from the Pit Mud of Nongxiangxing Baijiu

Caproic acid is a precursor substance for the synthesis of ethyl caproate, the main flavor substance of nongxiangxing baijiu liquor. In this study, Clostridium butyricum GD1-1, a strain with high caproic acid concentration (3.86 g/l), was isolated from the storage pit mud of nongxiangxing baijiu for sequencing and analysis. The strain's genome was 3,840,048 bp in length with 4,050 open reading frames. In addition, virulence factor annotation analysis showed C. butyricum GD1-1 to be safe at the genetic level. However, the annotation results using the Kyoto Encyclopedia of Genes and Genomes Automatic Annotation Server predicted a deficiency in the strain's synthesis of alanine, methionine, and biotin. These results were confirmed by essential nutrient factor validation experiments. Furthermore, the optimized medium conditions for caproic acid concentration by strain GD1-1 were (g/l): glucose 30, NaCl 5, yeast extract 10, peptone 10, beef paste 10, sodium acetate 11, L-cysteine 0.6, biotin 0.004, starch 2, and 2.0% ethanol. The optimized fermentation conditions for caproic acid production by C. butyricum GD1-1 on a single-factor basis were: 5% inoculum volume, 35°C, pH 7, and 90% loading volume. Under optimal conditions, the caproic acid concentration of strain GD1-1 reached 5.42 g/l, which was 1.40 times higher than the initial concentration. C. butyricum GD1-1 could be further used in caproic acid production, NXXB pit mud strengthening and maintenance, and artificial pit mud preparation.

Modulation of gut microbiota: a novel approach to enhancing the effects of immune checkpoint inhibitors

Although immune checkpoint inhibitors (ICIs) have greatly improved the prognosis of some cancer patients, the majority still fail to respond adequately, and the available biomarkers cannot reliably predict drug efficacy. The gut microbiota has received widespread attention among the various intrinsic and extrinsic factors contributing to drug resistance. As an essential regulator of physiological function, the impact of gut microbiota on host immunity and response to cancer therapy is increasingly recognized. Several studies have demonstrated significant differences in gut microbiota between responders and nonresponders. The gut microbiota associated with better clinical outcomes is called 'favorable gut microbiota'. Significantly, interventions can alter the gut microbiota. By shifting the gut microbiota to the 'favorable' one through various modifications, preclinical and clinical studies have yielded more pronounced responses and better clinical outcomes when combined with ICIs treatment, providing novel approaches to improve the efficacy of cancer immunotherapy. These findings may be attributed to the effects of gut microbiota and its metabolites on the immune microenvironment and the systemic immune system, but the underlying mechanisms remain to be discovered. In this review, we summarize the clinical evidence that the gut microbiota is strongly associated with the outcomes of ICI treatment and describe the gut microbiota characteristics associated with better clinical outcomes. We then expand on the current prevalent modalities of gut microbiota regulation, provide a comprehensive overview of preclinical and clinical research advances in improving the therapeutic efficacy and prognosis of ICIs by modulating gut microbiota, and suggest fundamental questions we need to address and potential directions for future research expansion.

An Update on the Pivotal Roles of Probiotics, Their Components, and Metabolites in Preventing Colon Cancer

Diet, lifestyle, and gut microbiota composition are key risk factors for the progression of colon cancer. Probiotics are living microorganisms that can offer health benefits to the parasitifer when ingested in competent quantities. Several in vivo, in vitro, and clinical studies have demonstrated that probiotics can prevent and mitigate the development of colon cancer. The anti-colon cancer mechanisms of probiotics include the suppression of cell proliferation and the promotion of cancer cell apoptosis, immunomodulation, the modulation of intestinal microorganisms and their metabolism, strengthening the intestinal barrier, and antioxidant effects. This article describes the pathogenesis of colon cancer and the available therapeutic options. In addition, this paper reviews the mechanisms by which probiotics mitigate colon cancer as well as the mitigating effects of probiotic components and metabolites on colon cancer.

Intestinal Microbiotas and Alcoholic Hepatitis: Pathogenesis and Therapeutic Value

Alcoholic hepatitis (AH) is a rapidly progressing and severe stage of alcoholic liver disease, presenting a grim prognosis. Extensive research has elucidated several underlying mechanisms that contribute to the development of AH, including metabolic alterations, immune stimulation, and intestinal dysbiosis. These pathological changes intricately intertwine during the progression of AH. Notably, recent studies have increasingly highlighted the pivotal role of alterations in the intestinal microbiota in the pathogenesis of AH. Consequently, future investigations should place significant emphasis on exploring the dynamics of intestinal microbiota. In this comprehensive review, we consolidate the primary causes of AH while underscoring the influence of gut microbes. Furthermore, by examining AH treatment strategies, we delineate the potential therapeutic value of interventions targeting the gut microbiota. Given the existing limitations in AH treatment options, we anticipate that this review will contribute to forthcoming research endeavors aimed at advancing AH treatment modalities.

Association between Probiotics and Modulation of Gut Microbial Community Composition in Colorectal Cancer Animal Models: A Systematic Review (2010-2021)

Background

Colorectal cancer (CRC) is one of the most prevalent gastrointestinal malignancies and is considered the third major cause of mortality globally. Probiotics have been shown to protect against the CRC cascade in numerous studies.

Aims

The goal of this systematic review was to gather the preclinical studies that examined the impact of probiotics on the alteration of gut microbiota profiles (bacterial communities) and their link to colorectal carcinogenesis as well as the potential processes involved.

Methods

The search was performed using Scopus, Web of Science, and PubMed databases. Five parameters were used to develop search filters: "probiotics," "prebiotics," "synbiotics," "colorectal cancer," and "animal model."

Results

Of the 399 full texts that were screened, 33 original articles met the inclusion criteria. According to the current findings, probiotics/synbiotics could significantly attenuate aberrant crypt foci (ACF) formation, restore beneficial bacteria in the microbiota population, increase short-chain fatty acids (SCFAs), and change inflammatory marker expression.

Conclusions

The present systematic review results indicate that probiotics could modulate the gut microbial composition and immune regulation to combat/inhibit CRC in preclinical models. However, where the evidence is more limited, it is critical to transfer preclinical research into clinical data.

Probiotics treatment ameliorated mycophenolic acid-induced colitis by enhancing intestinal barrier function and improving intestinal microbiota dysbiosis in mice

Background

Mycophenolic acid (MPA)-induced colitis was still a severe side effect and challenge faced by solid transplant recipients. We aimed to explore the function and mechanism of probiotics in the treatment of MPA-induced colitis.

Methods

In this study, 15 mice (C57BL/6) were randomly assigned into three groups: control (CNTL) group (n = 5), MPA group (n = 5) and the MPA + Probiotic group (n = 5). Bifid Triple Viable capsules, which were drugs for clinical use and consisted of Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis, were used in Probiotic group. Body weight change, stool scores, colon histopathology and morphology were used to evaluate the disease severity. The intestinal mucosal barrier function was assessed by measuring the expression level of secretory immunoglobulin A (sIgA), Zonula occludens-1 (ZO-1) and Occludin. Finally, 16S rDNA sequencing and bioinformatics analysis were performed on mice feces to compare the different intestinal microbial composition and diversity among three groups.

Results

Compared with the CNTL group, the mice in MPA group showed a significantly decreased body weight, increased stool scores, shortened colon length and severe colon inflammation. However, probiotics treated MPA mice reversed the disease severity, indicating that probiotics ameliorated MPA-induced colitis in mice. Mechanistically, probiotics improved the intestinal barrier function by up-regulating the expression of sIgA, ZO-1 and Occludin. Moreover, MPA-induced colitis led to intestinal microbiota dysbiosis, including the change of Firmicutes/Bacteroidetes ratio, α- and β-diversity. But probiotic treated group showed mild change in these microbial features. Additionally, we found that Clostridiales was the most significantly different microbiota flora in MPA group.

Conclusion

Probiotics treatment ameliorated MPA-induced colitis by enhancing intestinal barrier function and improving intestinal microbiota dysbiosis. Clostridiales might be the dominant functional intestinal microflora and serve as the potential therapy target in MPA-induced colitis.

Progress of gut microbiome and its metabolomics in early screening of colorectal cancer

Gut microbes are widely considered to be closely associated with colorectal cancer (CRC) development. The microbiota is regarded as a potential identifier of CRC, as several studies have found great significant changes in CRC patients' microbiota and metabolic groups. Changes in microbiota, like Fusobacterium nucleatum and Bacteroides fragilis, also alter the metabolic activity of the host, promoting CRC development. In contrast, the metabolome is an intuitive discriminative biomarker as a small molecular bridge to distinguish CRC from healthy individuals due to the direct action of microbes on the host. More diagnostic microbial markers have been found, and the potential discriminatory power of microorganisms in CRC has been investigated through the combined use of biomic genomic metabolomics, bringing new ideas for screening fecal microbial markers. In this paper, we discuss the potential of microorganisms and their metabolites as biomarkers in CRC screening, hoping to provide thoughts and references for non-invasive screening of CRC.

Tumorigenesis in Inflammatory Bowel Disease: Microbiota-Environment Interconnections

Colo-rectal cancer (CRC) is undoubtedly one of the most severe complications of inflammatory bowel diseases (IBD). While sporadic CRC develops from a typical adenoma-carcinoma sequence, IBD-related CRC follows different and less understood pathways and its pathophysiological mechanisms were not completely elucidated. In contrast to chronic inflammation, which is nowadays a well-recognised drive towards neoplastic transformation in IBD, only recently was gut microbiota demonstrated to interfere with both inflammation processes and immune-mediated anticancer surveillance. Moreover, the role of microbiota appears particularly complex and intriguing when also considering its multifaceted interactions with multiple environmental stimuli, notably chronic pathologies such as diabetes and obesity, lifestyle (diet, smoking) and vitamin intake. In this review, we presented a comprehensive overview on current evidence of the influence of gut microbiota on IBD-related CRC, in particular its mutual interconnections with the environment.

Clostridium butyricum inhibits epithelial-mesenchymal transition of intestinal carcinogenesis through downregulating METTL3

Colorectal cancer (CRC) is related to gut microbiota dysbiosis, especially butyrate-producing bacteria reduction. Our previous study suggested that administration of Clostridium butyricum, a butyrate-producing bacterium, exerts a crucial effect against CRC, however the potential mechanism is not clear. We first found that methyltransferase-like 3 (METTL3) showed a positive correlation with proliferation, epithelial-mesenchymal transition (EMT), DNA repair, metastasis, and invasion in a database analysis. The expression of METTL3 gradually increased from human normal colon tissue, to adenoma, and carcinoma, and was positively correlated with E-cadherin and CD34 levels. Overexpression of METTL3 promoted the proliferation, migration, and invasion of CRC cells and induced vasculogenic mimicry (VM) formation. Clostridium butyricum could downregulate METTL3 expression in CRC cells and decrease the expression of vimentin and vascular endothelial growth factor receptor 2 to reduce EMT and VM formation. Clostridium butyricum alleviated the pro-oncogenic effect of METTL3 overexpressing plasmid in CRC cells. The anti-EMT effect on METTL3 reduction of C. butyricum could be blunted by knocking down G-protein coupled receptor 43. Moreover, C. butyricum prevented EMT and VM and inhibited tumor metastasis in nude mice. Accordingly, C. butyricum could inhibit EMT and VM formation of intestinal carcinogenesis through downregulating METTL3. These findings broaden our understanding of probiotics supplement in CRC prevention and treatment.

Indole metabolites and colorectal cancer: Gut microbial tryptophan metabolism, host gut microbiome biomarkers, and potential intervention mechanisms

Tryptophan (Trp) functions in host-disease interactions. Its metabolism is a multi-pathway process. Indole and its derivatives are Trp metabolites unique to the human gut microbiota. Changes in Trp metabolism have also been detected in colorectal cancer (CRC). Here, combined with the existing CRC biomarkers, we ascribed it to the altered bacteria having the indole-producing ability by making a genomic prediction. We also reviewed the anti-inflammatory and possible anti-cancer mechanisms of indoles, including their effects on tumor cells, the ability to repair the gut barrier, regulation of the host immune system, and provide resistance against oxidative stress. Indole and its derivatives, along with related bacteria, could be targeted as auxiliary strategies to restrain cancer development in the future.

Inhibitory effects of Clostridium butyricum culture and supernatant on inflammatory colorectal cancer in mice

Clostridium butyricum (CB) is a spore-forming, gram-positive and obligate anaerobic rod bacterium. CB can modulate the composition of the gut microbiome and promote the growth of beneficial microbes in the intestine by generating short-chain fatty acids (SCFAs), which in turn protect against colitis and prevents the formation of inflammatory-associated colorectal cancer (CRC) by ameliorating colon inflammatory processes. Yet, it remains unclear whether the culture and supernatant of CB could directly influence inflammatory CRC in mice. In this study, azoxymethane (AOM)+dextran sodium sulphate (DSS) was used to induce CRC model in C57BL/6 mice. Next, the serum levels of inflammatory cytokines, including interleukin-6 (IL-6), interleukin-10 (IL-10), and cytokines TNF-α, were measured and the pathohistological examination of the large intestine was performed. Both CB culture and supernatant were found to have anti-inflammatory properties. Subsequently, Western blot and Real-Time Quantitative PCR (RT-qPCR) revealed that CB and supernatant regulate the NF-κB/p65 pathway to inhibit the development and progression of inflammatory CRC in AOM+DSS-treated mice, which could be due to the high levels of butyric acid in the supernatant.

Tebuconazole mediates cognitive impairment via the microbe-gut-brain axis (MGBA) in mice

Tebuconazole, one of the most widely used triazole fungicides, is reported to potentially pose a risk of inducing neurological disorders in human beings. Considering the increasing exposure, whether it could influence cognitive function remains to be elucidated. Herein, we used a mouse model to evaluate the potential cognitive risks and possible mechanisms from the continuous edible application of tebuconazole at low concentrations. Our study revealed that tebuconazole deteriorated spatial learning and memory and downregulated the expression of glutamate receptor subunits. Importantly, metagenomic analysis indicated that tebuconazole not only led to significant shifts in the composition and diversity of the gut microbiota but also changed intestinal homeostasis. Specifically, after exposure, tebuconazole circulated in the bloodstream and largely entered the gut-brain axis for disruption, including disturbing the Firmicutes/Bacteroidetes ratio, interrelated neurotransmitters and systemic immune factors. Moreover, pretreatment with probiotics improved immune factor expression and restored the deterioration of synaptic function and spatial learning and memory. The current study provides novel insights concerning perturbations of the gut microbiome and its functions as a potential new mechanism by which tebuconazole exposes cognitive function-related human health.

Gut Microbiota in Colorectal Cancer: Biological Role and Therapeutic Opportunities

Colorectal cancer (CRC) is the second-leading cause of cancer-related deaths worldwide. While CRC is thought to be an interplay between genetic and environmental factors, several lines of evidence suggest the involvement of gut microbiota in promoting inflammation and tumor progression. Gut microbiota refer to the ~40 trillion microorganisms that inhabit the human gut. Advances in next-generation sequencing technologies and metagenomics have provided new insights into the gut microbial ecology and have helped in linking gut microbiota to CRC. Many studies carried out in humans and animal models have emphasized the role of certain gut bacteria, such as Fusobacterium nucleatum, enterotoxigenic Bacteroides fragilis, and colibactin-producing Escherichia coli, in the onset and progression of CRC. Metagenomic studies have opened up new avenues for the application of gut microbiota in the diagnosis, prevention, and treatment of CRC. This review article summarizes the role of gut microbiota in CRC development and its use as a biomarker to predict the disease and its potential therapeutic applications.

Gut microbiota-derived short-chain fatty acids regulate gastrointestinal tumor immunity: a novel therapeutic strategy?

Tumor immune microenvironment (TIME), a tumor-derived immune component, is proven to be closely related to the development, metastasis, and recurrence of tumors. Gut microbiota and its fermented-metabolites short-chain fatty acids (SCFAs) play a critical role in maintaining the immune homeostasis of gastrointestinal tumors. Consisting mainly of acetate, propionate, and butyrate, SCFAs can interact with G protein-coupled receptors 43 of T helper 1 cell or restrain histone deacetylases (HDACs) of cytotoxic T lymphocytes to exert immunotherapy effects. Studies have shed light on SCFAs can mediate the differentiation and function of regulatory T cells, as well as cytokine production in TIME. Additionally, SCFAs can alter epigenetic modification of CD8⁺ T cells by inhibiting HDACs to participate in the immune response process. In gastrointestinal tumors, the abundance of SCFAs and their producing bacteria is significantly reduced. Direct supplementation of dietary fiber and probiotics, or fecal microbiota transplantation to change the structure of gut microbiota can both increase the level of SCFAs and inhibit tumor development. The mechanism by which SCFAs modulate the progression of gastrointestinal tumors has been elucidated in this review, aiming to provide prospects for the development of novel immunotherapeutic strategies.

The relationship between Clostridium butyricum and colorectal cancer

Gut microbiota dysbiosis is involved in intestinal diseases. The resident microorganisms in the digestive tract contribute to maintenance of gut homeostasis. Some bacterial species have been identified and are suspected to play a role in colorectal cancer (CRC). Many studies have found that Clostridium butyricum has a close relationship with CRC, and the mechanism is becoming increasingly clear. This review discusses the possible relationship between C. butyricum and CRC.

Amelioration of ammonia-induced intestinal oxidative stress by dietary Clostridium butyricum in giant freshwater prawn (Macrobrachium rosenbergii)

The use of Clostridium butyricum in crustacean aquaculture for anti-abiotic stress is yet unknown. Feeds were formulated containing 0, 125, 250, 500, and 1000 mg/kg Clostridium butyricum (2 × 10⁷ CFU/g), respectively. The giant freshwater prawns (Macrobrachium rosenbergii) were fed for 8 weeks in triplicate. The results showed that C. butyricum-supplemented groups improved growth performance significantly with the optimum level at 610 mg/kg. Ammonia stress reduced hemolymph glucose, total protein, total cholesterol, and triglyceride concentrations while dietary C. butyricum significantly increased hemolymph glucose and total protein levels after the ammonia challenge. Ammonia stress increased inducible nitric oxide synthase (iNOS) and nitric oxide (NO) levels, and the treatments supplemented with C. butyricum had considerably enhanced levels of iNOS and NO after stress. Treatment with C. butyricum increased the level of superoxide dismutase (SOD), and decreased the level of malondialdehyde (MDA) and superoxide anion, with the 125 mg/kg treated groups having the extreme value. Furthermore, C. butyricum-treated groups reduced the expression of HSPs after ammonia stress while the ammonia stress induced the expression of HSP60, HSP70, and HSP90. Dietary C. butyricum elevated the expression of peroxiredoxin-5 and toll in response to ammonia stress. The results indicate that dietary supplementation with 125-500 mg/kg of C. butyricum (2 × 10⁷ CFU/g) improved biochemical and antioxidant features as well as intestinal immunity of M. rosenbergii under ammonia challenge by activating the toll signal pathway.

Role of microbes in colorectal cancer therapy: Cross-talk between the microbiome and tumor microenvironment

The human gut microbiota is associated with the development and progression of colorectal cancer, and manipulation of the gut microbiota is a novel strategy for the prevention and treatment of colorectal cancer. Some bacteria have antitumor activity against colorectal cancer, where specific bacteria can improve the tumor microenvironment, activate immune cells including dendritic cells, helper T cells, natural killer cells, and cytotoxic T cells, and upregulate the secretion of pro-tumor immune cytokines such as interleukin-2 and interferon. In this paper, we summarize some bacteria with potential benefits in colorectal cancer and describe their roles in the tumor microenvironment, demonstrate the application of gut microbes in combination with immunosuppressive agents, and provide suggestions for further experimental studies and clinical practice applications.

Rapamycin Liposomes Combined with 5-Fluorouracil Inhibits Angiogenesis and Tumor Growth of APC (Min/+) Mice and AOM/DSS-Induced Colorectal Cancer Mice

BACKGROUND

Transgenic C57BL/6-APC^(Min/+) spontaneous cancer mouse model and the Azoxymethane (AOM)/Dextran Sulfate Sodium (DSS) chemically induced orthotopic colorectal cancer mouse model represented distinct pathogenesis of colorectal cancers. Our previous study revealed that the combination of Rapamycin liposomes (Rapa/Lps) and 5-Fluorouracil (5-FU) has anti-colorectal cancer effects. However, the therapeutic efficacy of Rapa/Lps and 5-FU in other colorectal cancer mice models is yet to be thoroughly explored. The purpose of this study was to investigate the anti-tumor effect of Rapa/Lps combined with 5-FU in vivo and in vitro.

METHODS

In this study, we evaluated the effect of Rapa/Lps and 5-FU on APC ^(Min/+) mice and AOM/DSS-induced colorectal cancer mice. The small intestine, colorectum, serum, and plasma of mice in each group were collected following sacrifice to record the number of tumors. HE staining was utilized for observing pathological damage to intestine tissues. Tube formation assay, Transwell assay, wound healing assay, Western Blot were used to explore the anti-angiogenesis effect of drugs in HUVECs.

RESULTS

As expected, Rapa/Lps and 5-FU significantly suppressed tumor formation, decreased the number of tumors, and tumor load both in two mouse models, and had no influence on mouse weight. Mechanically, the anti-tumor effect of the drug also was associated in inhibiting angiogenesis and proliferation. Furthermore, we found that Rapa/Lps obviously inhibited HUVECs tube formation and migration.

CONCLUSION

Altogether, we revealed the Rapa/Lps synergism with 5-FU decreased colon and small intestinal tumorigenesis in AOM/DSS-treated and APC ^(Min/+) mice, respectively, and correlated with anti-angiogenesis.

Regulation of gut microbiota-bile acids axis by probiotics in inflammatory bowel disease

Inflammatory bowel disease (IBD) is characterized by chronic and relapsing inflammation of gastrointestinal tract, with steadily increased incidence and prevalence worldwide. Although the precise pathogenesis remains unclear, gut microbiota, bile acids (BAs), and aberrant immune response play essential roles in the development of IBD. Lately, gut dysbiosis including certain decreased beneficial bacteria and increased pathogens and aberrant BAs metabolism have been reported in IBD. The bacteria inhabited in human gut have critical functions in BA biotransformation. Patients with active IBD have elevated primary and conjugated BAs and decreased secondary BAs, accompanied by the impaired transformation activities (mainly deconjugation and 7α-dehydroxylation) of gut microbiota. Probiotics have exhibited certain positive effects by different mechanisms in the therapy of IBD. This review discussed the effectiveness of probiotics in certain clinical and animal model studies that might involve in gut microbiota-BAs axis. More importantly, the possible mechanisms of probiotics on regulating gut microbiota-BAs axis in IBD were elucidated, which we focused on the elevated gut bacteria containing bile salt hydrolase or BA-inducible enzymes at genus/species level that might participate in the BA biotransformation. Furthermore, beneficial effects exerted by activation of BA-activated receptors on intestinal immunity were also summarized, which might partially explain the protect effects and mechanisms of probiotics on IBD. Therefore, this review will provide new insights into a better understanding of probiotics in the therapy targeting gut microbiota-BAs axis of IBD.

Changes of gut microbiota in colorectal cancer patients with Pentatrichomonas hominis infection

Pentatrichomonas hominis is a parasitic trichomonads protozoa that parasitizes in the colon and cecum of humans and other animals. Our previous studies have demonstrated that infection with P. hominis is associated with the incidence of colon cancer (37.93%). However, the mechanism by which P. hominis infections increase the incidence of colon cancer remains unclear. Previous studies have suggested that certain parasites promote colon cancer by regulating gut microbiota. This study aimed to elucidate whether the association between P. hominis infections and the increased incidence of colon cancer is related to changes in gut microbiota. Therefore, the gut microbiota patients with colon cancer who were infected with P. hominis and uninfected patients with colon cancer were analyzed by 16S rRNA high-throughput sequencing. The results demonstrated that patients with colon cancer who were not infected with P. hominis showed increased gut bacterial diversity, a higher relative abundance of Alcaligenes sp., Leucobacter sp., Paraprevotella sp., Ruminococcaceae UCG-002, and a significant reduction in the abundance of Veillonella sp., compared to individuals without colon cancer. Additionally, the relative abundance of the Ruminococcaceae UCG-002 and the Eubacterium eligens groups was reduced, while the relative abundance of bacteria associated with colon cancer, including Flavonifractor sp., Lachnoclostridium sp., and the Ruminococcus gnavus group, increased significantly in patients with colon cancer who were infected with P. hominis, compared to those of uninfected patients with colon cancer. In conclusion, these results suggested that P. hominis infections may aggravate the development of colon cancer and the findings provide new insights for subsequent in-depth studies on the pathogenesis, diagnosis, and prevention of colon cancer.

Presume Why Probiotics May Not Provide Protection in Inflammatory Bowel Disease through an Azoxymethane and Dextran Sodium Sulfate Murine Model

Recent studies have shown dysbiosis is associated with inflammatory bowel disease (IBD). However, trying to restore microbial diversity via fecal microbiota transplantation (FMT) or probiotic intervention fails to achieve clinical benefit in IBD patients. We performed a probiotic intervention on a simulated IBD murine model to clarify their relationship. IBD was simulated by the protocol of azoxymethane and dextran sodium sulfate (AOM/DSS) to set up a colitis and colitis-associated neoplasm model on BALB/c mice. A single probiotic intervention using Clostridium butyricum Miyairi (CBM) on AOM/DSS mice to clarify the role of probiotic in colitis, colitis-associated neoplasm, gut microbiota, and immune cytokines was performed. We found dysbiosis occurred in AOM/DSS mice. The CBM intervention on AOM/DSS mice failed to improve colitis and colitis-associated neoplasms but changed microbial composition and unexpectedly increased expression of proinflammatory IL-17A in rectal tissue. We hypothesized that the probiotic intervention caused dysbiosis. To clarify the result, we performed inverse FMT using feces from AOM/DSS mice to normal recipients to validate the pathogenic effect of dysbiosis from AOM/DSS mice and found mice on inverse FMT did develop colitis and colon neoplasms. We presumed the probiotic intervention to some extent caused dysbiosis as inverse FMT. The role of probiotics in IBD requires further elucidation.