Modulating gut microbes

Coculture of Bifidobacterium bifidum G9-1 With Butyrate-Producing Bacteria Promotes Butyrate Production

Supplementation with Bifidobacterium bifidum G9-1 (BBG9-1) has been established to enhance the production of butyrate, a short-chain fatty acid (SCFA) known for its beneficial effects in alleviating constipation. We hypothesized that BBG9-1 alters gut microbiota such that bacteria that produce butyric acid from lactate and acetate become more abundant. In this study, we sought to determine whether BBG9-1 promotes the growth of butyrate-producing bacteria and thereby enhances butyrate production. BBG9-1 was cocultured with different butyrate-producing bacteria to compare differences in the SCFA production of cocultures and monocultures. We indeed detected significant increases in the production of SCFAs in cocultures compared to monocultures. Moreover, lactate and butyrate production increased in a time-dependent manner in the BBG9-1 and Faecalibacterium prausnitzii ID 6052 coculture. In addition, acetate production in cocultures initially increased until 16 h, followed by a decline between 20 and 24 h, and a subsequent significant increase at 48 h. Comparatively, lactate and acetate production in the BBG9-1 and Anaerostipes caccae JCM 13470T coculture peaked at 16 h and declined thereafter, and butyrate production increased in a time-dependent manner. In contrast, lactate, acetate, and butyrate production in the BBG9-1 and Roseburia hominis JCM 17582T coculture increased in a time-dependent manner. These findings indicate that butyrate-producing bacteria increase butyrate production by utilizing BBG9-1-produced lactate and acetate. Thus, the butyrate-mediated physiological activity of BBG9-1 could be attributed to an indirect enhancement of butyrate production.

Regulatory role of gut microbiota in immunotherapy of hepatocellular carcinoma

BACKGROUND

The gut microbiota plays a role in triggering innate immunity and regulating the immune microenvironment (IME) of hepatocellular carcinoma (HCC) by acting on various signaling receptors and transcription factors through its metabolites and related molecules. Furthermore, there is an increasing recognition of the gut microbiota as a potential therapeutic target for HCC, given its ability to modulate the efficacy of immune checkpoint inhibitors (ICIs).

OBJECTIVE

This review will discuss the mechanisms of gut microbiota in modulating immunotherapy of HCC, the predictive value of efficacy, and the therapeutic strategies for modulating the gut microbiota in detail.

METHODS

We conducted a systematic literature search in PubMed, Embase, Scopus, Cochrane Library, China National Knowledge Infrastructure, and Wanfang Chinese databases for articles involving the influence of gut microbiota on HCC immunotherapy.

RESULTS

The mechanisms underlying the effect of gut microbiota on HCC immunotherapy include gut-liver axis, tumor immune microenvironment (TIME), and antibodies. Patients who benefit from ICIs exhibit a higher abundance of gut microbiota. Antibiotics, fecal microbiota transplantation (FMT), probiotics, and prebiotics are effective methods to regulate gut microbiota.

CONCLUSION

The strong connection between the liver and gut will provide numerous opportunities for the development of microbiome-based diagnostics, treatments, or prevention strategies for HCC patients.

Microfluidics-Based Microcarriers for Live-Cell Delivery

Live-cell therapy has emerged as a revolutionary treatment modality, providing a novel therapeutic avenue for intractable diseases. However, a major challenge in live-cell therapy is to maintain live-cell viability and efficacy during the treatment. Microcarriers are crucial for enhancing cell retention, viability, and functions by providing a protective scaffold and creating a supportive environment for live-cell proliferation and metabolism. For microcarrier construction, the microfluidic technology demonstrates excellent characteristics in terms of controllability over microcarrier size and morphology as well as potential for high-throughput production. To date, multiple live-cell delivery microcarrier types (e.g., microspheres, microfibers, and microneedles) are prepared via microfluidic liquid templates to meet different therapeutic needs. In this review, recent developments in microfluidics-based microcarriers for live-cell delivery are presented. It is focused on categorizing the structural design of microfluidic-derived cell-laden microcarriers, and summarizing various therapeutic applications. Finally, an outlook is provided on the future challenges and opportunities in this field.

Simulated digestion and gut microbiota fermentation of polysaccharides from Lactarius hatsudake Tanaka mushroom

Lactarius hatsudake Tanaka is a popular edible mushroom known for its delicious flavor and health benefits. Its polysaccharides (LHP) exhibit significant bioactivity, but their application is limited due to uncertainties in digestion. This study used in vitro simulated models to explore the dynamic changes of LHP during the digestive and fermentation process and validated them through mouse models. Results revealed that LHP cannot be digested by the simulated digestive system, but is primarily degraded into fatty acids by gut microbes, accompanied by reductions in molecular weight, carbohydrate content, and pH. Additionally, LHP promotes the proliferation of beneficial bacteria (Faecalibacterium, Bifidobacterium, Lactobacillus, etc.), while inhibiting harmful bacteria (Escherichia and Shigella). Metabolite analysis in serum indicated that LHP can regulate amino acid and lipid metabolism, enhancing overall health. These findings provide a theoretical foundation for developing LHP as a potential prebiotic, highlighting its considerable promise for disease prevention through improved intestinal health.

Ameba-inspired strategy enhances probiotic efficacy via prebound nutrient supply

Nutrient competition with indigenous microbes or pathogens presents a significant challenge for oral probiotic efficacy. To address this issue, we develop an ameba-inspired food-carrying strategy (AIFS) by prebinding ginger-derived exosome-like nanoparticles (GELNs) onto probiotics as food depots. AIFS enables probiotics to efficiently and exclusively consume GELNs in situ, even in the presence of competing bacteria. This results in up to 21 times higher uptake efficiency compared to unengineered probiotics, dramatically accelerating probiotic proliferation. Meanwhile, AIFS potentiates probiotics' resistance to multiple GI stressors. In a murine model of colitis, AIFS can improve the abundance of probiotics and inhibit pathogens, maintaining intestinal flora homeostasis. Additionally, it can upregulate the anti-inflammatory IL-10, reduce the proinflammatory IL-1β, and repair damaged intestinal mucus. Thereby, AIFS displays potently elevated prophylactic and therapeutic efficacy for colitis mice. This work provides a method for microbial engineering, with broad implications for microbiotherapy and gut health.

3-Hydroxypropionaldehyde modulates tryptophan metabolism to activate AhR signaling and alleviate ethanol-induced liver injury

BACKGROUND

Although probiotics-based therapies and postbiotics derived from Lactobacillus reuteri (L. reuteri) hold promising potential in mitigating alcohol-associated liver disease (ALD), the role of L. reuteri's metabolite, 3-Hydroxypropionaldehyde (3-HPA, reuterin), remains elusive.

PURPOSE

The objective of this study is to examine the influence of 3-HPA on the attenuation of alcohol-induced hepatic steatosis and its underlying mechanisms.

METHODS

The study utilizes network pharmacology to identify potential targets for 3-HPA in treating ALD. Comprehensive analytical methods, including histological and biochemical assessments, coupled with metabolomics techniques, are employed to evaluate the protective mechanisms and actions of 3-HPA in ALD. Additionally, the therapeutic potential of hepatic aryl hydrocarbon receptor (AhR) activation is explored through using both an AhR agonist and inhibitor, in order to assess the potential of 3-HPA as an AhR ligand in treating ALD.

RESULTS

Chronic alcohol consumption stimulates AhR activation in hepatocytes, both in vivo and in vitro, leading to the disruption of hepatic tryptophan metabolism. Our observations indicate that 3-HPA has the potential to regulate this process by activating AhR signaling through modulating tryptophan metabolism, specifically affecting indole acetaldehyde, indole, and 5‑hydroxy-l-tryptophan (5-HTP) levels. Mechanistically, 3-HPA demonstrates potential as an effective AhR agonist in mitigating ethanol-induced liver injury by regulating AhR-CD36 signaling, thereby exerting protective effects against hepatic steatosis.

CONCLUSION

Ultimately, the study identifies a previously uncharacterized role of 3-HPA in alleviating alcohol-associated liver injury and hepatic steatosis. It further elucidates that 3-HPA serves as a mediator in tryptophan metabolism, activating the AhR signaling, thereby suggesting its potential as a promising candidate for the treatment of ALD.

In vitro fermentation characteristics and modulation effects of polysaccharide fractions from Schisandra sphenanthera on intestinal microflora

Schisandra Sphenanthera polysaccharides fractions (SSPs), namely SSP40, SSP60, and SSP80, were obtained by gradient precipitation with 40 %, 60 %, and 80 % (v/v) ethanol, respectively. It was found that gradient ethanol precipitation (GEP) significantly affected the physicochemical and structural characteristics of SSPs, including molecular weight, monosaccharide composition, and surface morphology. Compared to fractions SSP40 and SSP60, SSP80 was observed to have a lower molecular weight (22.58 kDa) and certain specific monosaccharide composition, such as lower glucose content and higher galactose, arabinose, rhamnose, and galacturonic acid content. Furthermore, the apparent porosity of the SSPs increased with increasing ethanol concentration in GEP. After fermentation at 37 °C for 48 h, fraction SSP80 prominently promoted the production of more short-chain fatty acids (SCFAs), increasing from an initial 1.39 ± 0.08 to 26.75 ± 0.54 mmol/L. The SSP fraction types extracted by GEP greatly affected the modulation of the intestinal microflora at different levels. The SSP80 fraction with excellent structure demonstrated the best ability to modulate the intestinal microflora by increasing the relative abundance of Bacteroides, Faecalibacterium and Dialister and decreasing the relative abundance of Escherichia-Shigella. The remarkable differences in modulating the intestinal microflora confirmed the importance of carefully selecting GEP to fraction SSPs that promote health.

Angiogenesis, a key point in the association of gut microbiota and its metabolites with disease

The gut microbiota is a complex and dynamic ecosystem that plays a crucial role in human health and disease, including obesity, diabetes, cardiovascular diseases, neurodegenerative diseases, inflammatory bowel disease, and cancer. Chronic inflammation is a common feature of these diseases and is closely related to angiogenesis (the process of forming new blood vessels), which is often dysregulated in pathological conditions. Inflammation potentially acts as a central mediator. This abstract aims to elucidate the connection between the gut microbiota and angiogenesis in various diseases. The gut microbiota influences angiogenesis through various mechanisms, including the production of metabolites that directly or indirectly affect vascularization. For example, short-chain fatty acids (SCFAs) such as butyrate, propionate, and acetate are known to regulate immune responses and inflammation, thereby affecting angiogenesis. In the context of cardiovascular diseases, the gut microbiota promotes atherosclerosis and vascular dysfunction by producing trimethylamine N-oxide (TMAO) and other metabolites that promote inflammation and endothelial dysfunction. Similarly, in neurodegenerative diseases, the gut microbiota may influence neuroinflammation and the integrity of the blood-brain barrier, thereby affecting angiogenesis. In cases of fractures and wound healing, the gut microbiota promotes angiogenesis by activating inflammatory responses and immune effects, facilitating the healing of tissue damage. In cancer, the gut microbiota can either inhibit or promote tumor growth and angiogenesis, depending on the specific bacterial composition and their metabolites. For instance, some bacteria can activate inflammasomes, leading to the production of inflammatory factors that alter the tumor immune microenvironment and activate angiogenesis-related signaling pathways, affecting tumor angiogenesis and metastasis. Some bacteria can directly interact with tumor cells, activating angiogenesis-related signaling pathways. Diet, as a modifiable factor, significantly influences angiogenesis through diet-derived microbial metabolites. Diet can rapidly alter the composition of the microbiota and its metabolic activity, thereby changing the concentration of microbial-derived metabolites and profoundly affecting the host's immune response and angiogenesis. For example, a high animal protein diet promotes the production of pro-atherogenic metabolites like TMAO, activating inflammatory pathways and interfering with platelet function, which is associated with the severity of coronary artery plaques, peripheral artery disease, and cardiovascular diseases. A diet rich in dietary fiber promotes the production of SCFAs, which act as ligands for cell surface or intracellular receptors, regulating various biological processes, including inflammation, tissue homeostasis, and immune responses, thereby influencing angiogenesis. In summary, the role of the gut microbiota in angiogenesis is multifaceted, playing an important role in disease progression by affecting various biological processes such as inflammation, immune responses, and multiple signaling pathways. Diet-derived microbial metabolites play a crucial role in linking the gut microbiota and angiogenesis. Understanding the complex interactions between diet, the gut microbiota, and angiogenesis has the potential to uncover novel therapeutic targets for managing these conditions. Therefore, interventions targeting the gut microbiota and its metabolites, such as through fecal microbiota transplantation (FMT) and the application of probiotics to alter the composition of the gut microbiota and enhance the production of beneficial metabolites, present a promising therapeutic strategy.

The whole life journey and destination of microplastics: A review

Recent reports indicate that ubiquitous microplastics (MPs) in the environment can infiltrate the human body, posing significant health risks and garnering widespread attention. However, public understanding of the intricate processes through which microplastics are transferred to humans remains limited. Consequently, developing effective strategies to mitigate the escalating issue of MPs pollution and safeguard human health is still challenging. In this review, we elucidated the sources and dynamic migration pathways of MPs, examined its complex interactions with other pollutants, and identified primary routes of human exposure. Subsequently, the events and alterations of gut microbiota, gut microbiota metabolism, and intestinal barrier after MPs enter the gut of organisms are unclosed. Additionally, it highlighted the ease with which MPs translocate from the intestine to other organs along with their biological toxicities. Finally, we also emphasized the knowledge gaps in the current research field and proposes future research directions. This review aims to enhance public awareness regarding microplastic pollution and provide valuable references for forthcoming research endeavors as well as policy formulation related to this pressing issue.

Using lifestyle interventions and the gut microbiota to improve PTSD symptoms

Posttraumatic stress disorder is part of a spectrum of psychological symptoms that are frequently linked with a single defining traumatic experience. Symptoms can vary over the lifespan in intensity based on additional life stressors, individual stability, and connectedness to purpose. Historically, treatment has centered on psychotropic agents and individual and group therapy to increase the individual's window of tolerance, improve emotional dysregulation, and strengthen relationships. Unfortunately, there is a growing segment of individuals with posttraumatic stress disorder who do not respond to these traditional treatments, perhaps because they do not address the multidirectional relationships between chronic cortisol, changes in the brain gut microbiota system, neuroinflammation, and posttraumatic symptoms. We will review the literature and explain how trauma impacts the neuroendocrine and neuroimmunology within the brain, how these processes influence the brain gut microbiota system, and provide a mechanism for the development of posttraumatic stress disorder symptoms. Finally, we will show how the lifestyle psychiatry model provides symptom amelioration.

Extracellular Vesicles from Nanomedicine-Trained Intestinal Microbiota Substitute for Fecal Microbiota Transplant in Treating Ulcerative Colitis

The biosafety concerns associated with fecal microbiota transplant (FMT) limit their clinical application in treating ulcerative colitis (UC). Gut microbiota secrete abundant extracellular vesicles (Gm-EVs), which play a critical role in bacteria-to-bacteria and bacteria-to-host communications. Herein, intestinal microbiota are trained using tea leaf lipid/pluronic F127-coated curcumin nanocrystals (CN@Lp127s), which can maintain stability during transit through the gastrointestinal tract. Compared with FMT, Gm-EVs derived from healthy mice significantly improve treatment outcomes against UC by reducing colonic inflammatory responses, restoring colonic barrier function, and rebalancing intestinal microbiota. Strikingly, Gm-EVs obtained from CN@Lp127-trained healthy mice exhibit a superior therapeutic effect on UC compared to groups receiving FMT from healthy mice, Gm-EVs from healthy mice, and FMT from CN@Lp127-trained healthy mice. Oral administration of Gm-EVs from CN@Lp127-trained healthy mice not only alleviates colonic inflammation, promotes mucosal repair, and regulates gut microbiota but also regulates purine metabolism to decrease the uric acid level, resulting in a robust improvement in the UC. This study demonstrates the UC therapeutic efficacy of Gm-EVs derived from nanomedicine-trained gut microbiota in regulating the immune microenvironment, microbiota, and purine metabolism of the colon. These EVs provide an alternative platform to replace FMT as a treatment for UC.

A systematic framework for understanding the microbiome in human health and disease: from basic principles to clinical translation

The human microbiome is a complex and dynamic system that plays important roles in human health and disease. However, there remain limitations and theoretical gaps in our current understanding of the intricate relationship between microbes and humans. In this narrative review, we integrate the knowledge and insights from various fields, including anatomy, physiology, immunology, histology, genetics, and evolution, to propose a systematic framework. It introduces key concepts such as the 'innate and adaptive genomes', which enhance genetic and evolutionary comprehension of the human genome. The 'germ-free syndrome' challenges the traditional 'microbes as pathogens' view, advocating for the necessity of microbes for health. The 'slave tissue' concept underscores the symbiotic intricacies between human tissues and their microbial counterparts, highlighting the dynamic health implications of microbial interactions. 'Acquired microbial immunity' positions the microbiome as an adjunct to human immune systems, providing a rationale for probiotic therapies and prudent antibiotic use. The 'homeostatic reprogramming hypothesis' integrates the microbiome into the internal environment theory, potentially explaining the change in homeostatic indicators post-industrialization. The 'cell-microbe co-ecology model' elucidates the symbiotic regulation affecting cellular balance, while the 'meta-host model' broadens the host definition to include symbiotic microbes. The 'health-illness conversion model' encapsulates the innate and adaptive genomes' interplay and dysbiosis patterns. The aim here is to provide a more focused and coherent understanding of microbiome and highlight future research avenues that could lead to a more effective and efficient healthcare system.

Bidirectional Mendelian randomization to explore the causal relationships between the gut microbiota and male reproductive diseases

Gut bacteria might play an important role in male reproductive disorders, such as male infertility and sperm abnormalities; however, their causal role is unclear. Herein, Mendelian randomization (MR)-Egger, weighted median, inverse variance weighting, Simple mode, and Weighted mode were used to test the causal relationship between gut microbes and male reproductive diseases. The MR results were validated using various metrics. The MR results were also consolidated using reverse causality speculation, conducted using two-way MR analysis and Steiger filtering. Biological function was analysed using enrichment analyses. The results suggested that eight intestinal microflorae were causally associated with male infertility. The Eubacterium oxidoreducens group was associated with an increased risk of male infertility, while the family Bacteroidaceae was negatively associated with male reproductive diseases. Eight intestinal microflorae were causally associated with abnormal spermatozoa. The family Streptococcaceae was associated with a high risk of abnormal spermatozoa, whereas the family Porphyromonadaceae was associated with a low risk of abnormal spermatozoa. No pleiotropy was observed, this study identified a high correlation between the gut flora and the likelihood of male reproductive diseases. Future research will attempt to advance microbial-focused treatments for such diseases.

Exploring Therapeutic Advances: A Comprehensive Review of Intestinal Microbiota Modulators

The gut microbiota establishes a mutually beneficial relationship with the host starting from birth, impacting diverse metabolic and immunological processes. Dysbiosis, characterized by an imbalance of microorganisms, is linked to numerous medical conditions, including gastrointestinal disorders, cardiovascular diseases, and autoimmune disorders. This imbalance promotes the proliferation of toxin-producing bacteria, disrupts the host's equilibrium, and initiates inflammation. Genetic factors, dietary choices, and drug use can modify the gut microbiota. However, there is optimism. Several therapeutic approaches, such as probiotics, prebiotics, synbiotics, postbiotics, microbe-derived products, and microbial substrates, aim to alter the microbiome. This review thoroughly explores the therapeutic potential of these microbiota modulators, analysing recent studies to evaluate their efficacy and limitations. It underscores the promise of microbiota-based therapies for treating dysbiosis-related conditions. This article aims to ensure practitioners feel well-informed and up to date on the most influential methods in this evolving field by providing a comprehensive review of current research.

Microecological regulation in HCC therapy: Gut microbiome enhances ICI treatment

The exploration of the complex mechanisms of cancer immunotherapy is rapidly evolving worldwide, and our focus is on the interaction of hepatocellular carcinoma (HCC) with immune checkpoint inhibitors (ICIs), particularly as it relates to the regulatory role of the gut microbiome. An important basis for the induction of immune responses in HCC is the presence of specific anti-tumor cells that can be activated and reinforced by ICIs, which is why the application of ICIs results in sustained tumor response rates in the majority of HCC patients. However, mechanisms of acquired resistance to immunotherapy in unresectable HCC result in no long-term benefit for some patients. The significant heterogeneity of inter-individual differences in the gut microbiome in response to treatment with ICIs makes it possible to target modulation of specific gut microbes to assist in augmenting checkpoint blockade therapies in HCC. This review focuses on the complex relationship between the gut microbiome, host immunity, and HCC, and emphasizes that manipulating the gut microbiome to improve response rates to cancer ICI therapy is a clinical strategy with unlimited potential.

Materials-driven strategies in bacterial engineering

This perspective article focuses on the innovative field of materials-based bacterial engineering, highlighting interdisciplinary research that employs material science to study, augment, and exploit the attributes of living bacteria. By utilizing exogenous abiotic material interfaces, researchers can engineer bacteria to perform new functions, such as enhanced bioelectric capabilities and improved photosynthetic efficiency. Additionally, materials can modulate bacterial communities and transform bacteria into biohybrid microrobots, offering promising solutions for sustainable energy production, environmental remediation, and medical applications. Finally, the perspective discusses a general paradigm for engineering bacteria through the materials-driven modulation of their transmembrane potential. This parameter regulates their ion channel activity and ultimately their bioenergetics, suggesting that controlling it could allow scientists to hack the bioelectric language bacteria use for communication, task execution, and environmental response.

Graphical abstract

Bibliometric analysis of global research trends between gut microbiota and breast cancer: from 2013 to 2023

Background

Breast cancer is the most prevalent cancer globally and is associated with significant mortality. Recent research has provided crucial insights into the role of gut microbiota in the onset and progression of breast cancer, confirming its impact on the disease's management. Despite numerous studies exploring this relationship, there is a lack of comprehensive bibliometric analyses to outline the field's current state and emerging trends. This study aims to fill that gap by analyzing key research directions and identifying emerging hotspots.

Method

Publications from 2013 to 2023 were retrieved from the Web of Science Core Collection database. The VOSviewer, R language and SCImago Graphica software were utilized to analyze and visualize the volume of publications, countries/regions, institutions, authors, and keywords in this field.

Results

A total of 515 publications were included in this study. The journal Cancers was identified as the most prolific, contributing 21 papers. The United States and China were the leading contributors to this field. The University of Alabama at Birmingham was the most productive institution. Peter Bai published the most papers, while James J. Goedert was the most cited author. Analysis of highly cited literature and keyword clustering confirmed a close relationship between gut microbiota and breast cancer. Keywords such as "metabolomics" and "probiotics" have been prominently highlighted in the keyword analysis, indicating future research hotspots in exploring the interaction between metabolites in the breast cancer microenvironment and gut microbiota. Additionally, these keywords suggest significant interest in the therapeutic potential of probiotics for breast cancer treatment.

Conclusion

Research on the relationship between gut microbiota and breast cancer is expanding. Attention should be focused on understanding the mechanisms of their interaction, particularly the metabolite-microbiota-breast cancer crosstalk. These insights have the potential to advance prevention, diagnosis, and treatment strategies for breast cancer. This bibliometric study provides a comprehensive assessment of the current state and future trends of research in this field, offering valuable perspectives for future studies on gut microbiota and breast cancer.

The bacterial patterns suggesting the dynamic features of tick-associated microorganisms in hard ticks

BACKGROUND

Ticks are blood-feeding significant arthropods that can harbour various microorganisms, including pathogens that pose health risks to humans and animals. Tick-symbiont microorganisms are believed to influence tick development, but the intricate interactions between these microbes and the relationships between different tick-borne microorganisms remain largely unexplored.

RESULTS

Based on 111 tick pool samples presenting questing and engorged statuses including 752 questing tick and 1083 engorged tick from cattle and goats, which were collected in two types of geographic landscape (semi-desert and alpine meadow). We observed significant variations in the composition of tick-borne microorganisms across different environments and blood-engorgement statuses, with a pronounced divergence in symbionts compared to environmental bacteria. Metabolic predictions revealed over 90 differential pathways for tick-borne microorganisms in distinct environments and more than 80 metabolic variations in response to varying blood engorgement statuses. Interestingly, nine pathways were identified, particularly related to chorismate synthesis and carbohydrate metabolism. Moreover, microbial network relationships within tick-borne microorganism groups were highly distinct across different environments and blood-engorgement statuses. The microbial network relationships of symbionts involve some pathogenic and environmental microorganisms. Regression modelling highlighted positive correlations between the Coxiella symbiont and related pathogens, while some environmental bacteria showed strong negative correlations with Coxiella abundance. We also identified commensal bacteria/pathogens in bacterial cooccurrence patterns. Furthermore, we tested pathogenic microorganisms of each tick sample analysis revealed that 86.36% (1601/1855) of the tick samples carried one or more pathogenic microorganisms, The total carrier rate of bacterial pathogens was 43.77% ((812/1855). Most blood samples carried at least one pathogenic microorganism. The pathogens carried by the ticks have both genus and species diversity, and Rickettsia species are the most abundant pathogens among all pathogens.

CONCLUSION

Our findings underscore that the bacterial pattern of ticks is dynamic and unstable, which is influenced by the environment factors and tick developmental characteristics.

A Gas Therapy Strategy for Intestinal Flora Regulation and Colitis Treatment by Nanogel-Based Multistage NO Delivery Microcapsules

Current approaches to treating inflammatory bowel disease focus on the suppression of overactive immune responses, the removal of reactive intestinal oxygen species, and regulation of the intestinal flora. However, owing to the complex structure of the gastrointestinal tract and the influence of mucus, current small-molecule and biologic-based drugs for treating colitis cannot effectively act at the site of colon inflammation, and as a result, they tend to exhibit low efficacies and toxic side effects. In this study, nanogel-based multistage NO delivery microcapsules are developed to achieve NO release at the inflammation site by targeting the inflammatory tissues using the nanogel. Surprisingly, oral administration of the microcapsules suppresses the growth of pathogenic bacteria and increases the abundance of probiotic bacteria. Metabolomics further show that an increased abundance of intestinal probiotics promotes the production of metabolites, including short-chain fatty acids and indole derivatives, which modulate the intestinal immunity and restore the intestinal barrier via the interleukin-17 and PI3K-Akt signaling pathways. This work reveals that the developed gas therapy strategy based on multistage NO delivery microcapsules modulates the intestinal microbial balance, thereby reducing inflammation and promoting intestinal barrier repair, ultimately providing a new therapeutic approach for the clinical management of colitis.

Standards for fecal microbiota transplant: Tools and therapeutic advances

Fecal microbiota transplantation (FMT) has been demonstrated to be efficacious in preventing recurrent Clostridioides difficile (C. difficile) infections, and is being investigated for treatment of several other diseases including inflammatory bowel disease, cancer, obesity, liver disease, and diabetes. To speed up the translation of FMT into clinical practice as a safe and standardized therapeutic intervention, additional evidence-based technical and regulatory guidance is needed. To this end in May of 2022, the International Alliance for Biological Standardization (IABS) and the BIOASTER Microbiology Technology Institute hosted a second webinar to discuss key issues still impeding the advancement and standardization of FMT. The goal of this two-day webinar was to provide a forum for scientific experts to share and discuss data and key challenges with one another. Discussion included a focus on the evaluation of safety, efficacy, clinical trial design, reproducibility and accuracy in obtained microbiome measurements and data reporting, and the potential for standardization across these areas. It also focused on increasing the application potential and visibility of FMT beyond treating C. difficile infections.

Therapeutic bacteria and viruses to combat cancer: double-edged sword in cancer therapy: new insights for future

Cancer, ranked as the second leading cause of mortality worldwide, leads to the death of approximately seven million people annually, establishing itself as one of the most significant health challenges globally. The discovery and identification of new anti-cancer drugs that kill or inactivate cancer cells without harming normal and healthy cells and reduce adverse effects on the immune system is a potential challenge in medicine and a fundamental goal in Many studies. Therapeutic bacteria and viruses have become a dual-faceted instrument in cancer therapy. They provide a promising avenue for cancer treatment, but at the same time, they also create significant obstacles and complications that contribute to cancer growth and development. This review article explores the role of bacteria and viruses in cancer treatment, examining their potential benefits and drawbacks. By amalgamating established knowledge and perspectives, this review offers an in-depth examination of the present research landscape within this domain and identifies avenues for future investigation.

Mechanoelectronic stimulation of autologous extracellular vesicle biosynthesis implant for gut microbiota modulation

Pathogenic gut microbiota is responsible for a few debilitating gastrointestinal diseases. While the host immune cells do produce extracellular vesicles to counteract some deleterious effects of the microbiota, the extracellular vesicles are of insufficient doses and at unreliable exposure times. Here we use mechanical stimulation of hydrogel-embedded macrophage in a bioelectronic controller that on demand boost production of up to 20 times of therapeutic extracellular vesicles to ameliorate the microbes' deleterious effects in vivo. Our miniaturized wireless bioelectronic system termed inducible mechanical activation for in-situ and sustainable generating extracellular vesicles (iMASSAGE), leverages on wireless electronics and responsive hydrogel to impose mechanical forces on macrophages to produce extracellular vesicles that rectify gut microbiome dysbiosis and ameliorate colitis. This in vivo controllable extracellular vesicles-produced system holds promise as platform to treat various other diseases.

Advances in the study of the interaction between schistosome infections and the host's intestinal microorganisms

Schistosomiasis, also called bilharziasis, is a neglected tropical disease induced by schistosomes that infects hundreds of millions of people worldwide. In the life cycle of schistosomiasis, eggs are regarded as the main pathogenic factor, causing granuloma formation in the tissues and organs of hosts, which can cause severe gastrointestinal and liver granulomatous immune responses and irreversible fibrosis. Increasing evidence suggests that the gut microbiome influences the progression of schistosomiasis and plays a central role in liver disease via the gut-liver axis. When used as pharmaceutical supplements or adjunctive therapy, probiotics have shown promising results in preventing, mitigating, and even treating schistosomiasis. This review elucidates the potential mechanisms of this three-way parasite-host-microbiome interaction by summarizing schistosome-mediated intestinal flora disorders, local immune changes, and host metabolic changes, and elaborates the important role of the gut microbiome in liver disease after schistosome infection through the gut-liver axis. Understanding the mechanisms behind this interaction may aid in the discovery of probiotics as novel therapeutic targets and sustainable control strategies for schistosomiasis.

Probiotic-fermented edible herbs as functional foods: A review of current status, challenges, and strategies

Recently, consumers have become increasingly interested in natural, health-promoting, and chronic disease-preventing medicine and food homology (MFH). There has been accumulating evidence that many herbal medicines, including MFH, are biologically active due to their biotransformation through the intestinal microbiota. The emphasis of scientific investigation has moved from the functionally active role of MFH to the more subtle role of biotransformation of the active ingredients in probiotic-fermented MFH and their health benefits. This review provides an overview of the current status of research on probiotic-fermented MFH. Probiotics degrade toxins and anti-nutritional factors in MFH, improve the flavor of MFH, and increase its bioactive components through their transformative effects. Moreover, MFH can provide a material base for the growth of probiotics and promote the production of their metabolites. In addition, the health benefits of probiotic-fermented MFH in recent years, including antimicrobial, antioxidant, anti-inflammatory, anti-neurodegenerative, skin-protective, and gut microbiome-modulating effects, are summarized, and the health risks associated with them are also described. Finally, the future development of probiotic-fermented MFH is prospected in combination with modern development technologies, such as high-throughput screening technology, synthetic biology technology, and database construction technology. Overall, probiotic-fermented MFH has the potential to be used in functional food for preventing and improving people's health. In the future, personalized functional foods can be expected based on synthetic biology technology and a database on the functional role of probiotic-fermented MFH.

Adverse effects of fenpropathrin on the intestine of common carp (Cyprinus carpio L.) and the mechanism involved

Fenpropathrin (FEN), a pyrethroid pesticide, is frequently detected in natural water bodies, unavoidable pose adverse effects to aquatic organisms. However, the harmful effects and potential mechanisms of FEN on aquatic species are poorly understood. In this study, common carp were treatment with FEN at 0.45 and 1.35 μg/L for 14 d, and the toxic effects and underlying mechanisms of FEN on the intestine of carp were revealed. RNA-seq results showed that FEN exposure cause a wide range of transcriptional alterations in the intestine and the differentially expressed genes were mainly enrichment in the pathways related to immune and metabolism. Specifically, FEN exposure induced pathological damage and altered submicroscopic structure of the intestine, elevated the levels of Bacteroides fragilis enterotoxin, altered the contents of claudin-1, occludin, and zonula occluden-1 (ZO-1), and causing injury to the intestinal barrier. In addition, inflammation-related index TNF-α in the serum and IL-6 in the intestinal tissues were generally increased after FEN exposure. Moreover, FEN exposure promoted an increase in reactive oxygen species (ROS), altered the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), upregulated the contents of malondialdehyde (MDA) in the intestines. The apoptosis-related parameter cytochrome c, caspase-9, and caspase-3 were significantly altered, indicating that inflammation reaction, oxidative stress, and apoptosis may be involved in the toxic mechanism of FEN on carp. Moreover, FEN treatment also altered the intestinal flora community significantly, which may affect the intestinal normal physiological function and thus affect the growth of fish. Overall, the present study help to clarify the intestinal reaction mechanisms after FEN treatment, and provide a basis for the risk assessment of FEN.

Improving broiler health through cecal microbiota transplantation: a comprehensive study on growth, immunity, and microbial diversity

Cecal microbiota has emerged as a prominent intervention target for improving the production and welfare of poultry. This is essential for the overall health and performance of broiler chickens. The current study focused on investigating the effect of cecal microbiota transplantation (CMT) from healthy donor chickens on the growth performance, immunity, and microbial composition of newly hatched chicks and evaluated the effect of sample storage on the microbial diversity of the cecal samples. A healthy "Wannan Yellow Chicken line" was selected as the donor, and 180 1-d-old chicks from the same line were used as recipients for a 60-d feed trial. The chicks were randomly allocated to three groups (60 birds per group) with three replicates in each group. The three treatment groups were CMT-0 (control, normal saline solution), CMT-I (1:12 cecal content, normal saline supplemented with 10% glycerol), and CMT-II (1:6 cecal content, normal saline supplemented with 10% glycerol). The results of weight gain and absolute organ weight showed significant improvements in the CMT-II group compared with the CMT-0 group. Serum IgG level was significantly improved (P < 0.05) in CMT-I compared with that in the CMT-0. However, IL-6 levels increased in CMT-I and then significantly decreased in CMT-II. The cecal microbial diversity of CMT treatment was compared between two groups, fresh samples (FS) and stored samples at-80 °C (SS). The results showed that beneficial taxa, such as Firmicutes and Verrucomicrobiota, were substantially more abundant in both CMT-I and CMT-II than in CMT-0 in both FS and SS. Microbial function analysis at levels 1, 2, and 3 showed improved metabolism, genetic information processing, cellular processes, environmental information processing, and organismal systems in CMT-I and CMT-II for both FS and SS groups. However, the SS group showed decreased microbial diversity and function. To conclude, cecal microbiota transplantation is a promising strategy for enhancing the productivity and health of broiler chickens.

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.

Predictive Analysis of Quality Markers of Atractylodis Rhizoma Based on Fingerprint and Network Pharmacology

BACKGROUND

Atractylodes chinensis (DC.) Koidz. (A. chinensis) is a perennial herbaceous plant that is widely used as a Chinese medicine herb for gastric diseases. However, the bioactive compounds of this herbal medicine have not been defined, and quality control is imperfect.

OBJECTIVE

Although the method of quality evaluation method for A. chinensis by high-performance liquid chromatography (HPLC) fingerprinting has been reported in related papers, it remains unknown whether the chemical markers selected are representative of their clinical efficacy. To develop methods for qualitative analysis and improved quality evaluation of A. chinensis.

METHOD

In this study, HPLC was used to establish fingerprints and conduct similarity evaluation. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to reveal the differences of these fingerprints. Network pharmacology was used to analyze the corresponding targets of the active ingredients. Meantime, an active ingredient-target-pathway network was constructed to investigate the characteristics of the medical efficacy of A. chinensis and to predict potential Q-markers.

RESULTS

Combining network pharmacological effectiveness and composition specificity with the Q-marker concept, atractylodin (ATD), β-eudesmol, atractylenolide Ι (AT-I) and atractylenolide III (AT-III) were predicted to be potential Q-markers of A. chinensis that showed anti-inflammatory, antidepressant, anti-gastric, and antiviral effects by acting on 10 core targets and 20 key pathways.

CONCLUSIONS

The HPLC fingerprinting method established in this study is straightforward, and the identified four active constituents can be used as Q-markers of A. chinensis. These findings facilitate effective quality evaluation of A. chinensis and suggest this approach could be applied to evaluate the quality of other herbal medicines.

HIGHLIGHTS

The fingerprints of Atractylodis rhizoma were organically combined with network pharmacology to further clarify its criteria for quality control.

Understanding the mechanisms and translational implications of the microbiome for cancer therapy innovation

The intersection of the microbiota and cancer and the mechanisms that define these interactions are a fascinating, rapidly evolving area of cancer biology and therapeutics. Here we present recent insights into the mechanisms by which specific bacteria or their communities contribute to carcinogenesis and discuss the bidirectional interplay between microbiota and host gene or epigenome signaling. We conclude with comments on manipulation of the microbiota for the therapeutic benefit of patients with cancer.

Gut microbiota enhance energy accumulation of black-necked crane to cope with impending migration

Less is known about the role of gut microbiota in overwintering environmental adaptation in migratory birds. Here, we performed metagenomic sequencing on fresh fecal samples (n = 24) collected during 4 periods of overwintering (Dec: early; Jan: middle I; Feb: middle II; Mar: late) to characterize gut microbial taxonomic and functional characteristics of black-necked crane (Grus nigricollis). The results demonstrated no significant change in microbial diversity among overwintering periods. Analysis of compositions of microbiomes with bias correction (ANCOM-BC) determined 15 Proteobacteria species enriched in late overwintering period. Based on previous reports, these species are associated with degradation of chitin, cellulose, and lipids. Meanwhile, fatty acid degradation and betalain biosynthesis pathways are enriched in late overwintering period. Furthermore, metagenomic binning obtained 91 high-quality bins (completeness >70% and contamination <10%), 5 of which enriched in late overwintering period. Carnobacterium maltaromaticum, unknown Enterobacteriaceae, and Yersinia frederiksenii have genes for chitin and cellulose degradation, acetate, and glutamate production. Unknown Enterobacteriaceae and Y. frederiksenii hold genes for synthesis of 10 essential amino acids required by birds, and the latter has genes for γ-aminobutyrate production. C. maltaromaticum has genes for pyridoxal synthesis. These results implied the gut microbiota is adapted to the host diet and may help black-necked cranes in pre-migratory energy accumulation by degrading the complex polysaccharide in their diet, supplying essential amino acids and vitamin pyridoxal, and producing acetate, glutamate, and γ-aminobutyrate that could stimulate host feeding. Additionally, enriched Proteobacteria also encoded more carbohydrate-active enzymes (CAZymes) and antibiotic resistance genes (ARGs) in late overwintering period. KEY POINTS: • Differences in gut microbiota function during overwintering period of black-necked cranes depend mainly on changes in core microbiota abundance • Gut microbiota of black-necked crane adapted to the diet during overwintering period • Gut microbiota could help black-necked cranes to accumulate more energy in the late overwintering period.

Revitalizing myocarditis treatment through gut microbiota modulation: unveiling a promising therapeutic avenue

Numerous studies have demonstrated that gut microbiota plays an important role in the development and treatment of different cardiovascular diseases, including hypertension, heart failure, myocardial infarction, arrhythmia, and atherosclerosis. Furthermore, evidence from recent studies has shown that gut microbiota contributes to the development of myocarditis. Myocarditis is an inflammatory disease that often results in myocardial damage. Myocarditis is a common cause of sudden cardiac death in young adults. The incidence of myocarditis and its associated dilated cardiomyopathy has been increasing yearly. Myocarditis has gained significant attention on social media due to its association with both COVID-19 and COVID-19 vaccinations. However, the current therapeutic options for myocarditis are limited. In addition, little is known about the potential therapeutic targets of myocarditis. In this study, we review (1) the evidence on the gut-heart axis, (2) the crosslink between gut microbiota and the immune system, (3) the association between myocarditis and the immune system, (4) the impact of gut microbiota and its metabolites on myocarditis, (5) current strategies for modulating gut microbiota, (6) challenges and future directions for targeted gut microbiota in the treatment of myocarditis. The approach of targeting the gut microbiota in myocarditis is still in its infancy, and this is the study to explore the gut microbiota-immune system-myocarditis axis. Our findings are expected to pave the way for the use of gut microbiota as a potential therapeutic target in the treatment of myocarditis.

Antibiotic-induced gut bacteria depletion has no effect on HBV replication in HBV immune tolerance mouse model

Commensal microbiota is closely related to Hepatitis B virus (HBV) infection. Gut bacteria maturation accelerates HBV immune clearance in hydrodynamic injection (HDI) HBV mouse model. However, the effect of gut bacteria on HBV replication in recombinant adeno-associated virus (AAV)-HBV mouse model with immune tolerance remains obscure. We aim to investigate its role on HBV replication in AAV-HBV mouse model. C57BL/6 mice were administrated with broad-spectrum antibiotic mixtures (ABX) to deplete gut bacteria and intravenously injected with AAV-HBV to establish persistent HBV replication. Gut microbiota community was analyzed by fecal qPCR assay and 16S ribosomal RNA (rRNA) gene sequencing. HBV replication markers in blood and liver were determined by ELISA, qPCR assay and Western blot at indicated time points. Immune response in AAV-HBV mouse model was activated through HDI of HBV plasmid or poly(I:C) and then detected by quantifying the percentage of IFN-γ⁺/CD8⁺ T cells in the spleen via flow cytometry as well as the splenic IFN-γ mRNA level via qPCR assay. We found that antibiotic exposure remarkably decreased gut bacteria abundance and diversity. Antibiotic treatment failed to alter the levels of serological HBV antigens, intrahepatic HBV RNA transcripts and HBc protein in AAV-HBV mouse model, but contributed to HBsAg increase after breaking of immune tolerance. Overall, our data uncovered that antibiotic-induced gut bacteria depletion has no effect on HBV replication in immune tolerant AAV-HBV mouse model, providing new thoughts for elucidating the correlation between gut bacteria dysbiosis by antibiotic abuse and clinical chronic HBV infection.

A structure defined pectin SA02B from Semiaquilegia adoxoides is metabolized by human gut microbes

Polysaccharide is one of the major factors for shaping the gut microbiota. However, bioactivity of polysaccharide isolated from Semiaquilegia adoxoides on human gut microbiota remains unclear. Thus, we hypothesize gut microbes may act on it. Herein, pectin SA02B from the roots of Semiaquilegia adoxoides with molecular weight 69.26 kDa was elucidated. The backbone of SA02B was composed of alternate 1, 2-linked α-Rhap and 1, 4-linked α-GalpA, with branches of terminal (T) -, 1, 4-, 1, 3- and 1, 3, 6-linked β-Galp, T-, 1, 5- and 1, 3, 5-linked α-Araf and T-, 1, 4-linked-β-Xylp substituted at C-4 of 1, 2, 4-linked α-Rhap. Bioactivity screening showed SA02B promoted the growth of Bacteroides spp. which deconstructed it into monosaccharide. Simultaneously, we observed competition might exist between Bacteroides spp. and probiotics. Besides, we found that both Bacteroides spp. and probiotics could generate SCFAs grown on SA02B. Our findings highlight SA02B may deserve as a prebiotic to be explored to benefit the health gut microbiota.

Positive Health Outcomes Associated with Live Microbe Intake from Foods, Including Fermented Foods, Assessed using the NHANES Database

BACKGROUND

Live dietary microbes have been hypothesized to contribute to human health but direct evidence is lacking.

OBJECTIVES

This study aimed to determine whether the dietary consumption of live microbes is linked to improved health outcomes.

METHODS

Data from the NHANES 2001-2018 were used to assess microbial intake and their adjusted associations with selected physiological parameters (e.g., blood pressure, anthropometric measures, and biomarkers) among adults aged 19 y and older. Regression models were constructed to assess the microbial intake with each physiological parameter and adjusted for demographics and other covariates. Microbial intake was assessed as both a continuous variable and a 3-level categorical variable. Fermented foods were assessed in a separate model.

RESULTS

In continuous models, an additional 100-g intake of microbe-containing foods was associated with a lower systolic blood pressure (regression coefficient: -0.331; 95% CI: -0.447, -0.215 mm Hg), C-reactive protein (-0.013; 95% CI: -0.019, -0.008 mg/dL), plasma glucose -0.347; 95% CI: -0.570, -0.124 mg/dL), plasma insulin (-0.201; 95% CI: -0.304, -0.099 μU/mL), triglyceride (-1.389; 95% CI: -2.672, -0.106 mg/dL), waist circumference (-0.554; 95% CI: -0.679, -0.428 cm), and BMI -0.217; 95% CI: -0.273, -0.160 kg/m2) levels and a higher level of high density lipoprotein cholesterols (0.432; 95% CI: 0.289, 0.574 mg/dL). Patterns were broadly similar when microbial intake was assessed categorically and when fermented foods were assessed separately.

CONCLUSIONS

To our knowledge, this study is the first to quantify, in a nationally representative data set of American adults and using stable sets of covariates in the regression models, the adjusted associations of dietary intakes of live microbes with a variety of outcomes, such as anthropometric measures, biomarkers, and blood pressure levels. Our findings suggest that foods with higher microbial concentrations are associated with modest health improvements across a range of outcomes.

Change in the Gut Microbiome and Immunity by Lacticaseibacillus rhamnosus Probio-M9

With the exploding growth of the global market for probiotics and the rapid awakening of public awareness to manage health by probiotic intervention, there is still an active debate about whether the consumption of probiotics is beneficial for nonpatients, which is due to the lack of systematic analysis based on time series multiomics data sets. In this study, we recruited 100 adults from a college in China and performed a random case-control study by using a probiotic (Lacticaseibacillus rhamnosus Probio-M9) as an intervention for 6 weeks, aiming to achieve a comprehensive evaluation and understanding of the beneficial effect of Probio-M9 consumption. By testing advanced blood immunity indicators, sequencing the gut microbiome, and profiling the gut metabolome at baseline and the end of the study, we found that although the probiotic intervention has a limited impact on the human immunity and the gut microbiome and metabolome, the associations between the immunity indicators and multiomics data were strengthened, and further analysis of the gut microbiome's genetic variations revealed inhibited generation of single nucleotide variants (SNVs) by probiotic consumption. Taken together, our findings indicated an underestimated influence of the probiotic, not on altering the microbial composition but on strengthening the association between human immunity and commensal microbes and stabilizing the genetic variations of the gut microbiome. IMPORTANCE Although the global market for probiotics is growing explosively, there is still an active debate about whether the consumption of probiotics is beneficial for nonpatients. In this study, we recruited 100 adults from a college in China and performed 6 weeks of intervention for half of the volunteers. By analyzing the time series multiomics data in this study, we found that the probiotic intervention (i) has a limited effect on human immunity or the global structure of the gut microbiome and metabolome, (ii) can largely influence the correlation of the development between multiomics data and immunity, which was not able to be discovered by conventional differential abundance analysis, and (iii) can inhibit the generation of SNVs in the gut microbiome instead of promoting it.

A soil-inspired dynamically responsive chemical system for microbial modulation

Interactions between the microbiota and their colonized environments mediate critical pathways from biogeochemical cycles to homeostasis in human health. Here we report a soil-inspired chemical system that consists of nanostructured minerals, starch granules and liquid metals. Fabricated via a bottom-up synthesis, the soil-inspired chemical system can enable chemical redistribution and modulation of microbial communities. We characterize the composite, confirming its structural similarity to the soil, with three-dimensional X-ray fluorescence and ptychographic tomography and electron microscopy imaging. We also demonstrate that post-synthetic modifications formed by laser irradiation led to chemical heterogeneities from the atomic to the macroscopic level. The soil-inspired material possesses chemical, optical and mechanical responsiveness to yield write-erase functions in electrical performance. The composite can also enhance microbial culture/biofilm growth and biofuel production in vitro. Finally, we show that the soil-inspired system enriches gut bacteria diversity, rectifies tetracycline-induced gut microbiome dysbiosis and ameliorates dextran sulfate sodium-induced rodent colitis symptoms within in vivo rodent models.

Impact of the Host Microbiome on Vaccine Responsiveness: Lessons Learned and Future Perspective

Vaccination shows high variability in the elicited immune responses among individuals and populations for reasons still poorly understood. An increasing number of studies is supporting the evidence that gut microbiota, along with other interplaying variables, is able to modulate both humoral and cellular responses to infection and vaccination. Importantly, vaccine immunogenicity is often suboptimal at the extremes of age and also in low- and middle-income countries (LMICs), where the microbiota is believed to have an important role on immune responses. Still, contrasting findings and lack of causal evidence are calling for sophisticated methodologies to be able to overcome scientific and technical challenges to better decipher the immunomodulatory role of microbiota. In this perspective, we briefly review the status of the vaccine field in relation to the microbiome and offer possible scientific approaches to better understand the impact of the host microbiome on vaccine responsiveness.

Microbiome Therapeutics for Food Allergy

The prevalence of food allergies continues to rise, and with limited existing therapeutic options there is a growing need for new and innovative treatments. Food allergies are, in a large part, related to environmental influences on immune tolerance in early life, and represent a significant therapeutic challenge. An expanding body of evidence on molecular mechanisms in murine models and microbiome associations in humans have highlighted the critical role of gut dysbiosis in the pathogenesis of food allergies. As such, the gut microbiome is a rational target for novel strategies aimed at preventing and treating food allergies, and new methods of modifying the gastrointestinal microbiome to combat immune dysregulation represent promising avenues for translation to future clinical practice. In this review, we discuss the intersection between the gut microbiome and the development of food allergies, with particular focus on microbiome therapeutic strategies. These emerging microbiome approaches to food allergies are subject to continued investigation and include dietary interventions, pre- and probiotics, microbiota metabolism-based interventions, and targeted live biotherapeutics. This exciting frontier may reveal disease-modifying food allergy treatments, and deserves careful study through ongoing clinical trials.

Toward a Deeper Understanding of Gut Microbiome in Depression: The Promise of Clinical Applicability

The emergence of the coronavirus disease 2019 pandemic has dramatically increased the global prevalence of depression. Unfortunately, antidepressant drugs benefit only a small minority of patients. Thus, there is an urgent need to develop new interventions. Accumulating evidence supports a causal relationship between gut microbiota dysbiosis and depression. To advance microbiota-based diagnostics and therapeutics of depression, a comprehensive overview of microbial alterations in depression is presented to identify effector microbial biomarkers. This procedure generated 215 bacterial taxa from humans and 312 from animal models. Compared to controls, depression shows significant differences in β-diversity, but no changes in microbial richness and diversity. Additionally, species-specific microbial changes are identified like increased Eggerthella in humans and decreased Acetatifactor in rodent models. Moreover, a disrupted microbiome balance and functional changes, characterized by an enrichment of pro-inflammatory bacteria (e.g., Desulfovibrio and Escherichia/Shigella) and depletion of anti-inflammatory butyrate-producing bacteria (e.g., Bifidobacterium and Faecalibacterium) are consistently shared across species. Confounding effects of geographical region, depression type, and intestinal segments are also investigated. Ultimately, a total of 178 species and subspecies probiotics are identified to alleviate the depressive phenotypes. Current findings provide a foundation for developing microbiota-based diagnostics and therapeutics and advancing microbiota-oriented precision medicine for depression.

Modulation of the Gut Microbiome to Enhance Immunotherapy Response in Metastatic Melanoma Patients: A Clinical Review

For patients with metastatic melanoma, immunotherapy agents represent a promising treatment option, and researchers are actively seeking to identify factors that may predict a favorable response in patients. Recent studies have elucidated possible associations between the gut microbiome and the effects of immunotherapy, where variations in the gut microbiome may influence treatment response and frequency of adverse effects. In this clinical review, we describe the current literature related to the gut microbiome in the setting of immunotherapy, and we provide an overview of interventions under investigation that may modulate the gut microbiome. These interventions include fecal microbiota transplantation, probiotics, and dietary modifications.

Probiotics, Prebiotics, Synbiotics, and Fermented Foods as Potential Biotics in Nutrition Improving Health via Microbiome-Gut-Brain Axis

Biological, social, and psychological practices greatly affect the dietary intake of people; as a result, health-related complexities occur. Functional food and supplements have become popular due to their nutraceutical benefits, which make different choices of fermented food and beverages available to people. This review describes the characteristics of probiotics, prebiotics, post- and paraprobiotics, and their role in nutrition and in the sustainability of health. Currently, several synbiotic supplements have attracted consumers in the nutraceutical market to offer a number of health benefits, which are complementary mixtures of selected characterized probiotic cultures and prebiotic substrates. Traditional fermented foods consumed in different cultures are different than probiotics and symbiotic preparations, though these could be considered potential biotics in nutrition. Fermented foods are part of a staple diet in several countries and are cost-effective due to their preparation using seasonal raw materials available from local agriculture practices. Intake of all biotics discussed in this article is intended to improve the population of beneficial microbiota in the gut, which has proved important for the microbiome–gut–brain axis, influencing the activity of vagus nerve.

Gut microbiome in gastrointestinal cancer: a friend or foe?

The impact of the gut microbiome on host health is becoming increasingly recognized. To date, there is growing evidence that the complex characteristics of the microbial community play key roles as potential biomarkers and predictors of responses in cancer therapy. Many studies have shown that altered commensal bacteria lead to cancer susceptibility and progression in diverse pathways. In this review, we critically assess the data for gut microbiota related to gastrointestinal cancer, including esophageal, gastric, pancreatic, colorectal cancer, hepatocellular carcinoma and cholangiocarcinoma. Importantly, the underlying mechanisms of gut microbiota involved in cancer occurrence, prevention and treatment are elucidated. The purpose of this review is to provide novel insights for applying this understanding to the development of new therapeutic strategies in gastrointestinal cancer by targeting the microbial community.

Identification of Valerate as Carrying Capacity Modulator by Analyzing Lactiplantibacillus plantarum Colonization of Colonic Microbiota in vitro

Humans ingest many microorganisms, which may colonize and interact with the resident gut microbiota. However, extensive knowledge about host-independent microbe-microbe interactions is lacking. Here, we investigated such colonization process using a derivative of the model probiotic Lactiplantibacillus plantarum WCFS1 into continuously cultivated gut microbiota in the intestinal PolyFermS fermentation model inoculated with five independently immobilized human adult fecal microbiota. L. plantarum successfully colonized and organized itself spatially in the planktonic, that is, the reactor effluent, and sessile, that is, reactor biofilm, fractions of distinct human adult microbiota. The microbiota carrying capacity for L. plantarum was independent of L. plantarum introduction dose and second supplementation. Adult microbiota (n = 3) dominated by Prevotella and Ruminoccocus exhibited a higher carrying capacity than microbiota (n = 2) dominated by Bacteroides with 10⁵ and 10³ CFU/ml of L. plantarum, respectively. Cultivation of human adult microbiota over 3 months resulted in decreased carrying capacity and correlated positively with richness and evenness, suggesting enhanced resistance toward colonizers. Our analyses ultimately allowed us to identify the fermentation metabolite valerate as a modulator to increase the carrying capacity in a microbiota-independent manner. In conclusion, by uncoupling microbe-microbe interactions from host factors, we showed that L. plantarum colonizes the in vitro colonic community in a microbiota-dependent manner. We were further able to demonstrate that L. plantarum colonization levels were not susceptible to the introduction parameters dose and repeated administration but to microbiota features. Such knowledge is relevant in gaining a deeper ecological understanding of colonizer-microbiota interactions and developing robust probiotic strategies.

Spirulina platensis aqueous extracts ameliorate colonic mucosal damage and modulate gut microbiota disorder in mice with ulcerative colitis by inhibiting inflammation and oxidative stress

Ulcerative colitis (UC) is a chronic and recurrent inflammatory bowel disease (IBD) that has become a major gastroenterologic problem during recent decades. Numerous complicating factors are involved in UC development such as oxidative stress, inflammation, and microbiota disorder. These factors exacerbate damage to the intestinal mucosal barrier. Spirulina platensis is a commercial alga with various biological activity that is widely used as a functional ingredient in food and beverage products. However, there have been few studies on the treatment of UC using S. platensis aqueous extracts (SP), and the underlying mechanism of action of SP against UC has not yet been elucidated. Herein, we aimed to investigate the modulatory effect of SP on microbiota disorders in UC mice and clarify the underlying mechanisms by which SP alleviates damage to the intestinal mucosal barrier. Dextran sulfate sodium (DSS) was used to establish a normal human colonic epithelial cell (NCM460) injury model and UC animal model. The mitochondrial membrane potential assay 3-‍‍(4,5-dimethylthiazol-2-yl)-2,‍5-diphenyltetrazolium bromide (MTT) and staining with Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) and Hoechst 33258 were carried out to determine the effects of SP on the NCM460 cell injury model. Moreover, hematoxylin and eosin (H&E) staining, transmission electron microscopy (TEM), enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qPCR), western blot, and 16S ribosomal DNA (rDNA) sequencing were used to explore the effects and underlying mechanisms of action of SP on UC in C57BL/6 mice. In vitro studies showed that SP alleviated DSS-induced NCM460 cell injury. SP also significantly reduced the excessive generation of intracellular reactive oxygen species (ROS) and prevented mitochondrial membrane potential reduction after DSS challenge. In vivo studies indicated that SP administration could alleviate the severity of DSS-induced colonic mucosal damage compared with the control group. Inhibition of inflammation and oxidative stress was associated with increases in the activity of antioxidant enzymes and the expression of tight junction proteins (TJs) post-SP treatment. SP improved gut microbiota disorder mainly by increasing antioxidant enzyme activity and the expression of TJs in the colon. Our findings demonstrate that the protective effect of SP against UC is based on its inhibition of pro-inflammatory cytokine overproduction, inhibition of DSS-induced ROS production, and enhanced expression of antioxidant enzymes and TJs in the colonic mucosal barrier.

The Therapeutic Effect of SCFA-Mediated Regulation of the Intestinal Environment on Obesity

Intestinal environment disorder is a potential pathological mechanism of obesity. There is increasing evidence that disorders in the homeostasis of the intestinal environment can affect various metabolic organs, such as fat and liver, and lead to metabolic diseases. However, there are few therapeutic approaches for obesity targeting the intestinal environment. In this review, on the one hand, we discuss how intestinal microbial metabolites SCFA regulate intestinal function to improve obesity and the possible mechanisms and pathways related to obesity-related pathological processes (depending on SCFA-related receptors such as GPCRs, MCT and SMCT, and through epigenetic processes). On the other hand, we discuss dietary management strategies to enrich SCFA-producing bacteria and target specific SCFA-producing bacteria and whether fecal bacteria transplantation therapy to restore the composition of the gut microbiota to regulate SCFA can help prevent or improve obesity. Finally, we believe that it will be of great significance to establish a working model of gut– SCFA– metabolic disease development in the future for the improvement this human health concern.

Bacterial Lipopolysaccharide as a Negative Predictor of Adjuvant Gemcitabine Efficacy in Pancreatic Cancer

Adjuvant gemcitabine (aGC) is one standard of care after pancreatic ductal adenocarcinoma (PDAC) resection. No biomarker for its efficacy is established. As bacteria mediate gemcitabine resistance, we analyzed whether lipopolysaccharide (LPS) as surrogate for bacterial colonization is prognostic in PDAC patients treated with aGC or without aGC adjuvant gemcitabine. We detected LPS in 86 tumors from 376 patients, which defined a specific microbiome as revealed by 16 s-rRNA-sequencing. In the 230 aGC patients, LPS conferred worse disease-free survival (8.3 vs 13.7 months; hazard ratio = 1.75, 95% confidence interval = 1.22 to 2.49; log-rank P = .002) and overall survival (21.7 vs 28.5 months; hazard ratio = 1.80, 95% confidence interval = 1.23 to 2.57; log-rank P = .001) but not in the 146 naGC patients, which was confirmed in an independent validation cohort (n = 178). LPS may serve as a negative predictor for aGC efficacy in PDAC, which suggests a role for microbiome modification to overcome bacteria-mediated chemotherapy resistance.

Microbiota Transplantation in an Antibiotic-Induced Bacterial Depletion Mouse Model: Reproducible Establishment, Analysis, and Application

The fecal bacteria transplantation (FMT) technique is indispensable when exploring the pathogenesis and potential treatments for microbiota-related diseases. For FMT clinical treatments, there are already systematic guidelines for donor selection, fecal bacterial separation, FMT frequency, and infusion methods. However, only a few studies have demonstrated the use of standardized FMT procedures for animal models used in theoretical research, creating difficulties for many new researchers in this field. In the present paper, we provide a brief overview of FMT and discuss its contribution to the current understanding of disease mechanisms that relate to microbiota. This protocol can be used to generate a commonly used FMT mouse model and provides a literature reference of customizable steps.