Dietary nutrients shape gut microbes and intestinal mucosa via epigenetic modifications

Novel role of FTO in regulation of gut-brain communication via Desulfovibrio fairfieldensis-produced hydrogen sulfide under arsenic exposure

Fat mass and obesity-associated protein (FTO) is the key demethylase that reverses the abnormally altered N6-methyladenosine (m6A) modification in eukaryotic cells under environmental pollutants exposure. Arsenic is an environmental metalloid and can cause severe symptoms in human mainly through drinking water. However, there is no specific treatment for its toxic effects due to the uncovered mechanisms. We previously revealed that exposure to arsenic increased the level of m6A via down-regulation of FTO, which might serve as a potential target for intervention against arsenic-related disorders. In this study, our results demonstrated that chronic exposure to arsenic significantly disrupted the intestinal barrier and microenvironment. Also, this administration resulted in the enhancement of m6A modification and the reduction of FTO expression in the intestine. By using both CRISPR/Cas9-based FTO knock-in strategy and adeno-associated virus (AAV)-mediated overexpression of FTO in the intestine, we established for the first time that up-regulation of FTO remarkably ameliorated arsenic-induced disruption of intestinal barriers and altered microenvironment of mice. We also firstly identified a dominant gut microbial species, Desulfovibrio fairfieldensis, which was sharply reduced in arsenic-exposed mice, was able to proceed arsenic-induced neurobehavioral impairments by declining the levels of its major metabolite hydrogen sulfide. Administration of Desulfovibrio fairfieldensis could significantly alleviate the neurotoxicity of arsenic. Intriguingly, the beneficial effects of FTO against arsenic neurotoxicity possibly occurred through a novel gut-brain communication via Desulfovibrio fairfieldensis and its produced hydrogen sulfide. Collectively, these findings will provide new ideas for understanding the mechanisms of arsenic-induced toxic effects from a gut-brain communication perspective, and will assist the development of explicit intervention strategy via regulation of a new potential target FTO for prevention and treatment against arsenic-related both intestinal and neurological disorders.

Interplay of m6A RNA methylation and gut microbiota in modulating gut injury

The gut microbiota undergoes continuous variations among individuals and across their lifespan, shaped by diverse factors encompassing diet, age, lifestyle choices, medication intake, and disease states. These microbial inhabitants play a pivotal role in orchestrating physiological metabolic pathways through the production of metabolites like bile acids, choline, short-chain fatty acids, and neurotransmitters, thereby establishing a dynamic "gut-organ axis" with the host. The intricate interplay between the gut microbiota and the host is indispensable for gut health, and RNA N6-methyladenosine modification, a pivotal epigenetic mark on RNA, emerges as a key player in this process. M6A modification, the most prevalent internal modification of eukaryotic RNA, has garnered significant attention in the realm of RNA epigenetics. Recent findings underscore its potential to influence gut microbiota diversity and intestinal barrier function by modulating host gene expression patterns. Conversely, the gut microbiota, through its impact on the epigenetic landscape of host cells, may indirectly regulate the recruitment and activity of RNA m6A-modifying enzymes. This review endeavors to delve into the biological functions of m6A modification and its consequences on intestinal injury and disease pathogenesis, elucidating the partial possible mechanisms by which the gut microbiota and its metabolites maintain host intestinal health and homeostasis. Furthermore, it also explores the intricate crosstalk between them in intestinal injury, offering a novel perspective that deepens our understanding of the mechanisms underlying intestinal diseases.

Microbiota, mitochondria, and epigenetics in health and disease: converging pathways to solve the puzzle

Dysbiosis, which refers to an imbalance in the composition of the gut microbiome, has been associated with a range of metabolic disorders, including type 2 diabetes, obesity, and metabolic syndrome. Although the exact mechanisms connecting gut dysbiosis to these conditions are not fully understood, various lines of evidence strongly suggest a substantial role for the interaction between the gut microbiome, mitochondria, and epigenetics. Current studies suggest that the gut microbiome has the potential to affect mitochondrial function and biogenesis through the production of metabolites. A well-balanced microbiota plays a pivotal role in supporting normal mitochondrial and cellular functions by providing metabolites that are essential for mitochondrial bioenergetics and signaling pathways. Conversely, in the context of illnesses, an unbalanced microbiota can impact mitochondrial function, leading to increased aerobic glycolysis, reduced oxidative phosphorylation and fatty acid oxidation, alterations in mitochondrial membrane permeability, and heightened resistance to cellular apoptosis. Mitochondrial activity can also influence the composition and function of the gut microbiota. Because of the intricate interplay between nuclear and mitochondrial communication, the nuclear epigenome can regulate mitochondrial function, and conversely, mitochondria can produce metabolic signals that initiate epigenetic changes within the nucleus. Given the epigenetic modifications triggered by metabolic signals from mitochondria in response to stress or damage, targeting an imbalanced microbiota through interventions could offer a promising strategy to alleviate the epigenetic alterations arising from disrupted mitochondrial signaling.

Gut Microbiota Mediates Neuroinflammation in Alzheimer's Disease: Unraveling Key Factors and Mechanistic Insights

The gut microbiota, the complex community of microorganisms that inhabit the gastrointestinal tract, has emerged as a key player in the pathogenesis of neurodegenerative disorders, including Alzheimer's disease (AD). AD is characterized by progressive cognitive decline and neuronal loss, associated with the accumulation of amyloid-β plaques, neurofibrillary tangles, and neuroinflammation in the brain. Increasing evidence suggests that alterations in the composition and function of the gut microbiota, known as dysbiosis, may contribute to the development and progression of AD by modulating neuroinflammation, a chronic and maladaptive immune response in the central nervous system. This review aims to comprehensively analyze the current role of the gut microbiota in regulating neuroinflammation and glial cell function in AD. Its objective is to deepen our understanding of the pathogenesis of AD and to discuss the potential advantages and challenges of using gut microbiota modulation as a novel approach for the diagnosis, treatment, and prevention of AD.

Quercetin-Driven Akkermansia Muciniphila Alleviates Obesity by Modulating Bile Acid Metabolism via an ILA/m6A/CYP8B1 Signaling

Global health is increasingly challenged by the growing prevalence of obesity and its associated complications. Quercetin, one of the most important dietary flavonoids, is being explored as an effective therapy for obesity with its mechanism remains understudied. Here in this study, it is demonstrated that quercetin intervention significantly reverses obesity-related phenotypes through reshaping the overall structure of microbiota, especially boosting colonization of the beneficial gut commensal Akkermansia muciniphila (A. muciniphila). Enrichment of A. muciniphila leads to generate more indole-3-lactic acid (ILA) to upregulate the expression of 12α-hydroxylase (CYP8B1) via fat mass and obesity-associated protein (FTO)/ N6-methyladenosine (m6A)/YTHDF2 manner, thereby facilitating cholesterol converts to cholic acid (CA). CA in turn drastically suppresses lipid accumulation via activating the farnesoid X receptor (FXR) in adipose tissue. This work introduces a novel therapeutic target for addressing obesity and expands upon the current limited understanding of the mediator function of m6A modifications in microorganism-influenced bile acid (BA) metabolism.

Neohesperidin Mitigates High-Fat-Diet-Induced Colitis In Vivo by Modulating Gut Microbiota and Enhancing SCFAs Synthesis

Previous research has consistently shown that high-fat diet (HFD) consumption can lead to the development of colonic inflammation. Neohesperidin (NHP), a naturally occurring flavanone glycoside in citrus fruits, has anti-inflammatory properties. However, the efficacy and mechanism of NHP in countering prolonged HFD-induced inflammation remains unclear. In this study, rats on HFD were intragastrically administered (i.g.) with NHP for 12 consecutive weeks. Results indicate that this natural compound is effective in reducing colorectal inflammation at doses of 40-80 mg/kg body weight (BW) by i.g. administration, with significant decreases in inflammation markers such as TNF-α and IL-1β levels. It also improved intestinal mucosal tissue integrity and reduced HFD-stimulated colorectal inflammation via the JAK2/STAT3 pathway. Furthermore, intestinal microbiota sequencing results show that NHP intervention significantly downregulated the Firmicutes/Bacteroidetes ratio. This ratio is closely related to the preventive role in the context of glycolipid metabolism disorder. Compared with fecal cultures of rats from the HFD group, after 48 h in vitro fermentation, those from the NHP group had distinct microbiota composition and notably higher concentrations of SCFAs. Collectively, these observations suggest that 80 mg/kg BW NHP possesses biological activities in downregulating HFD-induced colorectal inflammation by regulating intestinal flora and promoting SCFAs formation.

Limosilactobacillus reuteri ZY15 Alleviates Intestinal Inflammation and Barrier Dysfunction via AKT/mTOR/HIF-1α/RORγt/IL-17 Signaling and the Gut Microbiota in ETEC K88-Challenged Mice

Limosilactobacillus reuteri, a recognized probiotic, improves intestinal health in animals, but the mechanism remains unclear. This study investigates the mechanisms by which L. reuteri ZY15, isolated from healthy pig feces, mitigates intestinal barrier damage and inflammation caused by oxidative stress in Enterotoxigenic Escherichia coli (ETEC) K88-challenged mice. The results indicated that L. reuteri ZY15 increased antioxidant capacity by reducing serum reactive oxygen species (ROS) and superoxide dismutase (SOD) levels. L. reuteri ZY15 enhanced the intestinal barrier by upregulating mucin 1, mucin 2, occludin, zonula occludens-1 (ZO-1), and claudin-1 expressions in protein and mRNA levels. It significantly alleviated intestinal inflammation by reducing the proinflammatory cytokines interleukin-1β (IL-1β), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and interleukin-17 (IL-17) mRNA and protein levels. Notably, L. reuteri ZY15 suppressed intestinal inflammation by inhibiting AKT/mTOR/HIF-1α/RORγt/IL-17 pathway activation. Additionally, it significantly altered the structure of gut microorganisms by enriching Akkermansia and Clostridia_UCG.014, and thereby re-establishing colonization resistance and alleviating ETEC K88-induced intestinal barrier damage and inflammation in mice. Taken together, our findings reveal the protective mechanism of L. reuteri ZY15 in mice challenged with ETEC K88 by regulating AKT/mTOR/HIF-1α/RORγt/IL-17 signaling and microbial imbalance. Leveraging these properties, live L. reuteri ZY15 offers a promising alternative treatment for Escherichia coli-induced diarrhea in weaned piglets.

Boar semen microbiome: Insights and potential implications

The pioneers of next-generation sequencing technology and bioinformatic analyses initiated a new era in microbiology research by offering profound insights into bacterial microbiome communities. In the pig farming sector, while considerable attention has been devoted to the gut microbiome and the microbiome of the female reproductive tract, research on the microbiome of boar semen remains limited. Nonetheless, published studies have provided valuable insights, serving as important references and sparking ideas for further investigations into the seminal microbiome. Factors such as breed, seasons, feed additives, hygiene management, and antibiotic use are believed to exert a notable influence on the diversity and richness of bacterial genera in the boar seminal microbiome, potentially affecting semen quality. Moreover, current shifts towards sustainability in the swine industry, coupled with global guidelines concerning the prudent use of antibiotics in stored boar semen for artificial insemination, underscore the need for insights into factors influencing seminal bacteria. The objective of this review is to elucidate the current understanding of boar bacterial contents using conventional culture methods, as well as the boar seminal microbiome through metagenomics and bioinformatics. It also aims to review specific microbiome communities, such as those in the reproductive tract and gut, and their connections to semen quality. In addition, strategic enhancements for processing boar semen doses through alternative methods to improve seminal quality are proposed.

Interplay between gut microbiome, host genetic and epigenetic modifications in MASLD and MASLD-related hepatocellular carcinoma

Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses a wide spectrum of liver injuries, ranging from hepatic steatosis, metabolic dysfunction-associated steatohepatitis (MASH), fibrosis, cirrhosis to MASLD-associated hepatocellular carcinoma (MASLD-HCC). Recent studies have highlighted the bidirectional impacts between host genetics/epigenetics and the gut microbial community. Host genetics influence the composition of gut microbiome, while the gut microbiota and their derived metabolites can induce host epigenetic modifications to affect the development of MASLD. The exploration of the intricate relationship between the gut microbiome and the genetic/epigenetic makeup of the host is anticipated to yield promising avenues for therapeutic interventions targeting MASLD and its associated conditions. In this review, we summarise the effects of gut microbiome, host genetics and epigenetic alterations in MASLD and MASLD-HCC. We further discuss research findings demonstrating the bidirectional impacts between gut microbiome and host genetics/epigenetics, emphasising the significance of this interconnection in MASLD prevention and treatment.

The Composition and Function of Intestinal Microbiota Were Altered in Farmed Bullfrog Tadpoles (Aquarana catesbeiana) during Metamorphosis

The bullfrog Aquarana catesbeiana is one of the main farmed frog species in China, with a low overall survival of farmed bullfrogs from hatching to harvest since bullfrog tadpoles are fragile during the metamorphosis period. The intestinal bacterial community can play crucial roles in animal development; however, little is known about the alteration of the gut microbial community of A. catesbeiana during metamorphosis. The present study used 16S rRNA amplicon sequencing to investigate the intestinal bacterial community in A. catesbeiana at four distinct developmental stages. Moreover, we determined the bullfrog's body morphological parameters and the intestine histology at different developmental stages. The results showed a reduction in the total length and snout-vent length of A. catesbeiana during metamorphosis. The intestinal microbial composition of A. catesbeiana exhibited variation throughout the process of metamorphosis. The terrestrial stage showed shifts in the bacterial composition compared to the aquatic stages, including a reduction in Bacteroidetes and an increase in Firmicutes. Furthermore, the presence of Prevotella, Bifidobacterium, Leucobacter, Corynebacterium, Bulleidia, Dorea, Robinsoniella, and Clostridium in A. catesbeiana metamorphosis appears to be mainly related to the host's epithelial cells' height and total body mass. The results indicated that the intestinal microbial composition changed with the bullfrog-tadpole metamorphosis. The genera of Prevotella, Bifidobacterium, Leucobacter, Corynebacterium, Bulleidia, Dorea, Robinsoniella, and Clostridium might be potential probiotics.

Fluoride exposure-induced gut microbiota alteration mediates colonic ferroptosis through N6-methyladenosine (m6A) mediated silencing of SLC7A11

Fluoride exposure is widespread worldwide and poses a significant threat to organisms, particularly to their gastrointestinal tracts. However, due to limited knowledge of the mechanism of fluoride induced intestinal injury, it has been challenging to develop an effective treatment. To address this issue, we used a series of molecular biology in vitro and in vivo experiments. NaF triggered m6A mediated ferroptosis to cause intestinal damage. Mechanistically, NaF exposure increased the m6A level of SLC7A11 mRNA, promoted YTHDF2 binding to m6A-modified SLC7A11 mRNA, drove the degradation of SLC7A11 mRNA, and led to a decrease in its protein expression, which eventually triggers ferroptosis. Moreover, NaF aggravated ferroptosis of the colon after antibiotics destroyed the composition of gut microbiota. 16 S rRNA sequencing and SPEC-OCCU plots, Zi-Pi relationships, and Spearman correlation coefficients verified that Lactobacillus murinus (ASV54, ASV58, and ASV82) plays a key role in the response to NaF-induced ferroptosis. Collectively, NaF-induced gut microbiota alteration mediates severe intestinal cell injury by inducing m6A modification-mediated ferroptosis. Our results highlight a key mechanism of the gut in response to NaF exposure and suggest a valuable theoretical basis for its prevention and treatment.

hucMSC-Ex alleviates inflammatory bowel disease in mice by enhancing M2-type macrophage polarization via the METTL3-Slc37a2-YTHDF1 axis

Human umbilical cord mesenchymal stem cell-derived exosomes (hucMSC-Ex) have emerged as a new treatment strategy for inflammatory bowel disease (IBD) due to their immunoregulatory function. N6-methyladenosine (m6A) plays a crucial role in regulating intestinal immunity, especially in IBD where macrophages play an important role, although its mechanism is not yet fully understood. From this perspective, this research aimed to evaluate the effect of hucMSC-Ex on m6A modification of macrophages in IBD. In the process of alleviating inflammation, hucMSC-Ex promotes macrophage polarization toward the M2 type and regulates intracellular m6A levels by upregulating the expression of m6A "Writer" METTL3 and "Reader" YTHDF1. Solute Carrier Family 37 Member 2 (Slc37a2) was identified by Methylation RNA immunoprecipitation sequencing as the target molecule of the hucMSC-Ex. Mechanically, hucMSC-Ex promoted the binding of METTL3 to the Slc37a2 mRNA complex, and enhanced the binding of Slc37a2 to YTHDF1 to upregulate the intracellular expression of Slc37a2, thereby attenuating the pro-inflammatory function of macrophage. This study confirms the modulatory role of hucMSC-Ex on the m6A modification of macrophages in IBD, providing a new scientific basis for the treatment of IBD with hucMSC-Ex.

Transplanting network pharmacology technology into food science research: A comprehensive review on uncovering food-sourced functional factors and their health benefits

Network pharmacology is an emerging interdisciplinary research method. The application of network pharmacology to reveal the nutritional effects and mechanisms of active ingredients in food is of great significance in promoting the development of functional food, facilitating personalized nutrition, and exploring the mechanisms of food health effects. This article systematically reviews the application of network pharmacology in the field of food science using a literature review method. The application progress of network pharmacology in food science is discussed, and the mechanisms of functional factors in food on the basis of network pharmacology are explored. Additionally, the limitations and challenges of network pharmacology are discussed, and future directions and application prospects are proposed. Network pharmacology serves as an important tool to reveal the mechanisms of action and health benefits of functional factors in food. It helps to conduct in-depth research on the biological activities of individual ingredients, composite foods, and compounds in food, and assessment of the potential health effects of food components. Moreover, it can help to control and enhance their functionality through relevant information during the production and processing of samples to guarantee food safety. The application of network pharmacology in exploring the mechanisms of functional factors in food is further analyzed and summarized. Combining machine learning, artificial intelligence, clinical experiments, and in vitro validation, the achievement transformation of functional factor in food driven by network pharmacology is of great significance for the future development of network pharmacology research.

Flaxseed promotes productive performance through regulating gut microbiome in ducks

BACKGROUND

Flaxseed has been widely used in animal diets to increase the omega-3 polyunsaturated fatty acid content in animal products and promote overall animal health, but little known about its effects on the productive performance and the mictobita of gut of laying duck.

METHODS AND RESULTS

Jinding duck, a Chinese indigenous breed, was used in the study. The corn-soybean basal diet supplemented with 0, 2%, 3% 4% and 5% flaxseed were provided to Control, 2% Fla, 3% Fla, 4% Fla and 5% Fla groups for 53 days, respectively. Compared with Control group, groups fed with flaxseed diets showed higher egg production, egg mass, ovary weight and more preovulatory follicles. The Docosahexaenoic Acid content of egg was extremely significantly elevated by flaxseed diets (P < 0.01), and the albumen height and haugh unit were elevated, especially in 4% Fla and/or 5% Fla group (P < 0.05). Groups 4% Fla and 5% Fla had highest ileal villus height, jejunal and ileal crypt depth. Moreover, Flaxseed diets significantly increased the levels of IgG and IgM in all Fla groups (P < 0.01), while increased IgA levels except for in 3% Fla group (P < 0.05). The results of 16s rDNA sequencing showed that flaxseed diet altered the microbial composition of gut and reduced the diversity and evenness of gut microbial communities except for 5% Fla. The correlation analysis identified Blautia, Butyricicoccus and Subdoligranulum positively associated with egg production. Genera Fourinierella, Fusobacterium and Intestinimonas positively associated with ovary weight, haught unit and album height. And Mucispirillum positively associated with haugh unit and album height.

CONCLUSION

This study has suggested that flaxseed play a positive role in productive performance, the overall or intestinal health of laying ducks.

Epigenetics and environmental health

Epigenetic modifications including DNA methylation, histone modifications, chromatin remodeling, and RNA modifications complicate gene regulation and heredity and profoundly impact various physiological and pathological processes. In recent years, accumulating evidence indicates that epigenetics is vulnerable to environmental changes and regulates the growth, development, and diseases of individuals by affecting chromatin activity and regulating gene expression. Environmental exposure or induced epigenetic changes can regulate the state of development and lead to developmental disorders, aging, cardiovascular disease, Alzheimer's disease, cancers, and so on. However, epigenetic modifications are reversible. The use of specific epigenetic inhibitors targeting epigenetic changes in response to environmental exposure is useful in disease therapy. Here, we provide an overview of the role of epigenetics in various diseases. Furthermore, we summarize the mechanism of epigenetic alterations induced by different environmental exposures, the influence of different environmental exposures, and the crosstalk between environmental variation epigenetics, and genes that are implicated in the body's health. However, the interaction of multiple factors and epigenetics in regulating the initiation and progression of various diseases complicates clinical treatments. We discuss some commonly used epigenetic drugs targeting epigenetic modifications and methods to prevent or relieve various diseases regulated by environmental exposure and epigenetics through diet.

Gut microbiome and metabolome alterations in traditional Chinese medicine damp-heat constitution following treatment with a Chinese patent medicine and lifestyle intervention

BACKGROUND

The gut microbiota is crucial in human health and diseases. Traditional Chinese Medicine Constitution (TCMC) divides people into those with a balanced constitution (Ping-he [PH]) and those with an unbalanced constitution. Dampness-heat constitution (Shi-re [SR]) is a common unbalanced constitution in the Chinese population and is susceptible to diseases. However, unbalanced constitutions can be regulated by Chinese medicine and lifestyle interventions in clinical practice. Ermiao Pill (EMP) is a Chinese medicine known for clearing heat and draining dampness and improving SR. However, the efficacy and mechanism of EMP are unclear.

HYPOTHESIS/PURPOSE

To determine alterations in the gut microbiota and metabolome in SR and any changes after EMP treatment combined with lifestyle intervention.

STUDY DESIGN

Randomized clinical trial.

METHODS

We enrolled 112 healthy SR individuals and evaluated the efficacy of EMP along with lifestyle interventions. We further assessed serum cytokine levels, serum and urinary metabolomes, and the gut microbiota by 16S rRNA gene sequencing analysis before and after the EMP and lifestyle interventions.

RESULTS

107 SR individuals (55 in the intervention group and 52 in the control group) completed the 1-month-intervention and 1-year-follow-up. The intervention group significantly improved their health status within 1 month, with a reduced SR symptom score, and the efficacy lasted to the 1-year follow-up. The control group needed a further 6 months to reduce the SR symptom score. The gut microbiota of PH individuals was more diverse and had significantly higher proportions of many bacterial species than the SR. Microbiota co-occurrence network analysis showed that SR enriches metabolites correlating with microbial community structure, consistent with traits of healthy SR-enriched microbiota.

CONCLUSION

EMP combined with lifestyle intervention produced health benefits in SR individuals. Our study indicates a pivotal role of gut microbiota and metabolome alterations in distinguishing between healthy SR and PH. Furthermore, the study reveals structural changes of gut microbiota and metabolites induced by EMP and lifestyle intervention. The treatment enriched the number of beneficial bacteria, such as Akkermansia muciniphila and Lactobacillus in the gut. Our findings provide a strong indication that several metabolite factors are associated with the gut microbiota. Moreover, the gut microbiome and metabolome might be powerful tools for TCMC diagnosis and personalized therapy.

Changes in M6A methylation: A key factor in the vicious cycle of flora -gut aging

The aging process significantly impacts the gastrointestinal tract and various bodily systems, exacerbating age-related diseases. Research suggests a correlation between an imbalance in intestinal flora and gut aging, yet the precise mechanism remains incompletely elucidated. Epigenetic modifications, particularly m6A methylation, play a pivotal role in driving aging and are closely associated with gut aging. Maintaining a healthy balance of intestinal microbes is contingent upon m6A methylation, which is believed to be crucial in the vicious cycle of gut aging and intestinal flora. This article highlights the importance of m6A methylation in the nexus between gut aging and flora. It proposes the potential for targeted m6A methylation to break the vicious cycle of gut aging and flora imbalance, offering novel perspectives on attenuating or reversing gut aging.

Antibiotic-Induced Gut Microbiota Dysbiosis Modulates Host Transcriptome and m6A Epitranscriptome via Bile Acid Metabolism

Gut microbiota can influence host gene expression and physiology through metabolites. Besides, the presence or absence of gut microbiome can reprogram host transcriptome and epitranscriptome as represented by N6-methyladenosine (m6A), the most abundant mammalian mRNA modification. However, which and how gut microbiota-derived metabolites reprogram host transcriptome and m6A epitranscriptome remain poorly understood. Here, investigation is conducted into how gut microbiota-derived metabolites impact host transcriptome and m6A epitranscriptome using multiple mouse models and multi-omics approaches. Various antibiotics-induced dysbiotic mice are established, followed by fecal microbiota transplantation (FMT) into germ-free mice, and the results show that bile acid metabolism is significantly altered along with the abundance change in bile acid-producing microbiota. Unbalanced gut microbiota and bile acids drastically change the host transcriptome and the m6A epitranscriptome in multiple tissues. Mechanistically, the expression of m6A writer proteins is regulated in animals treated with antibiotics and in cultured cells treated with bile acids, indicating a direct link between bile acid metabolism and m6A biology. Collectively, these results demonstrate that antibiotic-induced gut dysbiosis regulates the landscape of host transcriptome and m6A epitranscriptome via bile acid metabolism pathway. This work provides novel insights into the interplay between microbial metabolites and host gene expression.

Nurturing gut health: role of m6A RNA methylation in upholding the intestinal barrier

The intestinal lumen acts as a critical interface connecting the external environment with the body's internal state. It's essential to prevent the passage of harmful antigens and bacteria while facilitating nutrient and water absorption. The intestinal barriers encompass microbial, mechanical, immunological, and chemical elements, working together to maintain intestinal balance. Numerous studies have associated m6A modification with intestinal homeostasis. This review comprehensively outlines potential mechanisms through which m6A modification could initiate, exacerbate, or sustain barrier damage from an intestinal perspective. The pivotal role of m6A modification in preserving intestinal equilibrium provides new insights, guiding the exploration of m6A modification as a target for optimizing preventive and therapeutic strategies for intestinal homeostasis.

Obesity and male fertility disorders

Often associated with obesity, male infertility represents a widespread condition that challenges the wellbeing of the couple. In this article, we provide a comprehensive and critical analysis of studies exploring the association between obesity and male reproductive function, to evaluate the frequency of this association, and establish the effects of increased body weight on conventional and biofunctional sperm parameters and infertility. In an attempt to find possible molecular markers of infertility in obese male patients, the numerous mechanisms responsible for infertility in overweight/obese patients are reviewed in depth. These include obesity-related functional hypogonadism, insulin resistance, hyperinsulinemia, chronic inflammation, adipokines, irisin, gut hormones, gut microbiome, and sperm transcriptome. According to meta-analytic evidence, excessive body weight negatively influences male reproductive health. This can occurr through a broad array of molecular mechanisms. Some of these are not yet fully understood and need to be further elucidated in the future. A better understanding of the effects of metabolic disorders on spermatogenesis and sperm fertilizing capacity is very useful for identifying new diagnostic markers and designing therapeutic strategies for better clinical management of male infertility.

Regulation Mechanism and Potential Value of Active Substances in Spices in Alcohol-Liver-Intestine Axis Health

Excessive alcohol intake will aggravate the health risk between the liver and intestine and affect the multi-directional information exchange of metabolites between host cells and microbial communities. Because of the side effects of clinical drugs, people tend to explore the intervention value of natural drugs on diseases. As a flavor substance, spices have been proven to have medicinal value, but they are still rare in treating hepatointestinal diseases caused by alcohol. This paper summarized the metabolic transformation of alcohol in the liver and intestine and summarized the potential value of various perfume active substances in improving liver and intestine diseases caused by alcohol. It is also found that bioactive substances in spices can exert antioxidant activity in the liver and intestine environment and reduce the oxidative stress caused by diseases. These substances can interfere with fatty acid synthesis, promote sugar and lipid metabolism, and reduce liver injury caused by steatosis. They can effectively regulate the balance of intestinal flora, promote the production of SCFAs, and restore the intestinal microenvironment.

Lactobacillus reuteri biofilms formed on porous zein/cellulose scaffolds: Synbiotics to regulate intestinal microbiota

Supplementing probiotics or indigestible carbohydrates is a usual strategy to prevent or revert unhealthy states of the gut by reshaping gut microbiota. One criterion that probiotics are efficacious is the capacity to survive in the gastrointestinal tract. Biofilm is the common growth mode of microorganisms with high tolerances toward harsh environments. Suitable scaffolds are crucial for successful biofilm culture and large-scale production of biofilm-phenotype probiotics. However, the role of scaffolds containing indigestible carbohydrates in biofilm formation has not been studied. In this study, porous zein/cellulose composite scaffolds provided nitrogen sources and carbon sources simultaneously at the solid/liquid interfaces, being beneficial to the biofilm formation of Lactobacillus reuteri. The biofilms showed 2.1-17.4 times higher tolerances in different gastrointestinal conditions. In human fecal fermentation, the biofilms combined with the zein/cellulose composite scaffolds act as the "synbiotics" positively modulating the gut microbiota and the short-chain fatty acids (SCFAs), where biofilms provide probiotics and scaffolds provide prebiotics. The "synbiotics" show a more positive regulation ability than planktonic L. reuteri, presenting potential applications in gut health interventions. These results provide an understanding of the synergistic effects of biofilm-phenotype probiotics and indigestible carbohydrates contained in the "synbiotics" in gut microbiota modulation.

Microbiota Alterations in Lung, Ileum, and Colon of Guinea Pigs with Cough Variant Asthma

Alterations in the microbiota composition, or ecological dysbiosis, have been implicated in the development of various diseases, including allergic diseases and asthma. Examining the relationship between microbiota alterations in the host and cough variant asthma (CVA) may facilitate the discovery of novel therapeutic strategies. To elucidate the diversity and difference of microbiota across three ecological niches, we performed 16S rDNA amplicon sequencing on lung, ileum, and colon samples. We assessed the levels of interleukin-12 (IL-12) and interleukin-13 (IL-13) in guinea pig bronchoalveolar lavage fluid using the enzyme-linked immunosorbent assay (ELISA). We applied Spearman's analytical method to evaluate the correlation between microbiota and cytokines. The results demonstrated that the relative abundance, α-diversity, and β-diversity of the microbial composition of the lung, ileum, and colon varied considerably. The ELISA results indicated a substantial increase in the level of IL-13 and a decreasing trend in the level of IL-12 in the CVA guinea pigs. The Spearman analysis identified a correlation between Mycoplasma, Faecalibaculum, and Ruminococcus and the inflammatory factors in the CVA guinea pigs. Our guinea pig model showed that core microorganisms, such as Mycoplasma in the lung, Faecalibaculum in the ileum, and Ruminococcus in the colon, may play a crucial role in the pathogenesis of CVA. The most conspicuous changes in the ecological niche were observed in the guinea pig ileum, followed by the lung, while relatively minor changes were observed in the colon. Notably, the microbial structure of the ileum niche approximated that of the colon niche. Therefore, the results of this study suggest that CVA development is closely related to the dysregulation of ileal, lung, and colon microbiota and the ensuing inflammatory changes in the lung.

High diversity, close genetic relatedness, and favorable living conditions benefit species co-occurrence of gut microbiota in Brandt's vole

Introduction

Revealing factors and mechanisms in determining species co-existence are crucial to community ecology, but studies using gut microbiota data are still lacking.

Methods

Using gut microbiota data of 556 Brandt's voles from 37 treatments in eight experiments, we examined the relationship of species co-occurrence of gut microbiota in Brandt's voles (Lasiopodomys brandtii) with genetic distance (or genetic relatedness), community diversity, and several environmental variables.

Results

We found that the species co-occurrence index (a larger index indicates a higher co-occurrence probability) of gut microbiota in Brandt's voles was negatively associated with the genetic distance between paired ASVs and the number of cohabitating voles in the experimental space (a larger number represents more crowding social stress), but positively with Shannon diversity index, grass diets (representing natural foods), and non-physical contact within an experimental space (representing less stress).

Discussion

Our study demonstrated that high diversity, close genetic relatedness, and favorable living conditions would benefit species co-occurrence of gut microbiota in hosts. Our results provide novel insights into factors and mechanisms that shape the community structure and function of gut microbiota and highlight the significance of preserving the biodiversity of gut microbiota.

The health benefits of dietary short-chain fatty acids in metabolic diseases

Short-chain fatty acids (SCFAs) are a subset of fatty acids that play crucial roles in maintaining normal physiology and developing metabolic diseases, such as obesity, diabetes, cardiovascular disease, and liver disease. Even though dairy products and vegetable oils are the direct dietary sources of SCFAs, their quantities are highly restricted. SCFAs are produced indirectly through microbial fermentation of fibers. The biological roles of SCFAs in human health and metabolic diseases are mainly due to their receptors, GPR41 and GPR43, FFAR2 and FFAR3. Additionally, it has been demonstrated that SCFAs modulate DNMTs and HDAC activities, inhibit NF-κB-STAT signaling, and regulate G(i/o)βγ-PLC-PKC-PTEN signaling and PPARγ-UCP2-AMPK autophagic signaling, thus mitigating metabolic diseases. Recent studies have uncovered that SCFAs play crucial roles in epigenetic modifications of DNAs, RNAs, and post-translational modifications of proteins, which are critical regulators of metabolic health and diseases. At the same time, dietary recommendations for the purpose of SCFAs have been proposed. The objective of the review is to summarize the most recent research on the role of dietary SCFAs in metabolic diseases, especially the signal transduction of SCFAs in metabolic diseases and their functional efficacy in different backgrounds and models of metabolic diseases, at the same time, to provide dietary and nutritional recommendations for using SCFAs as food ingredients to prevent metabolic diseases.

Epigenetic modification of m6A methylation: Regulatory factors, functions and mechanism in inflammatory bowel disease

Although the exact cause of inflammatory bowel disease (IBD) is still unknown, there is a lot of evidence to support the notion that it results from a combination of environmental factors, immune system issues, gut microbial changes, and genetic susceptibility. In recent years, the role of epigenetics in the pathogenesis of IBD has drawn increasing attention. The regulation of IBD-related immunity, the preservation of the intestinal epithelial barrier, and autophagy are all significantly influenced by epigenetic factors. The most extensive epigenetic methylation modification of mammalian mRNA among them is N6-methyladenosine (m6A). It summarizes the general structure and function of the m6A regulating factors, as well as their complex effects on IBD by regulating the intestinal mucous barrier, intestine mucosal immunity, epidermal cell death, and intestinal microorganisms.This paper provides key insights for the future identification of potential new targets for the diagnosis and treatment of IBD.

Effects of Peanuts and Pistachios on Gut Microbiota and Metabolic Syndrome: A Review

There is growing evidence that the gut microbiota is associated with various aspects of human health, including immune system regulation, vitamin synthesis, short-chain fatty acid production, etc. Peanuts and pistachios are foods rich in protein, unsaturated fatty acids, vitamins, polyphenols, and other dietary components that have been shown to benefit the gut microbiota. Therefore, this review aims to describe the effects of consuming peanuts and pistachios on the gut microbiota and the potential role of these microbiota in human health. This review suggests that the consumption of peanuts or pistachios can demonstrate the potential to exert a beneficial effect on the gut microbiota by promoting the growth of beneficial gut bacteria that produce, for example, short-chain fatty acids that are beneficial for human health. In the case of peanuts, in particular, the possible modulation of the microbiota is associated with an improvement in the risk factors of metabolic syndrome and the inflammatory process triggered by a high-fat diet.

On the road to colorectal cancer development: crosstalk between the gut microbiota, metabolic reprogramming, and epigenetic modifications

An increasing number of studies have reported the role of gut microbes in colorectal cancer (CRC) development, as they can be influenced by dietary metabolism and mediate alterations in host epigenetics, ultimately affecting CRC. Intake of specific dietary components can affect gut microbial composition and function, and their metabolism regulates important epigenetic functions that may influence CRC risk. Gut microbes can regulate epigenetic modifications through nutrient metabolism, including histone modification, DNA methylation, and noncoding RNAs. Epigenetics, in turn, determines the gut microbial composition and thus influences the risk of developing CRC. This review discusses the complex crosstalk between metabolic reprogramming, gut microbiota, and epigenetics in CRC and highlights the potential applications of the gut microbiota as a biomarker for the prevention, diagnosis, and therapy of CRC.

An Association between Decreased Small Intestinal RNA Modification and Disturbed Glucagon-like Peptide-1 Secretion under High-Fat Diet Stress

Unhealthy diets rich in fats and/or sugar are considered as the major external cause of the obesity epidemic, which is often accompanied by a significant decrease in gut hormone glucagon-like peptide-1 (GLP1) levels. Numerous studies have demonstrated notable contributions of the gut microbiota in this process. Nevertheless, the underlying mechanism still needs further investigation. The role of epigenetic modifications in gene expression and metabolism has been well demonstrated, with m6A methylation on RNAs being the most prevalent modification throughout their metabolism. In the present study, we found that the expressions of small intestinal Gcg and Pc3, two key genes regulating GLP1 expression, were significantly downregulated in obese mice, associated with reduced GLP1 level. Immunohistochemistry analysis indicated that a high-fat diet slightly increased the density of enteroendocrine L cells in the small intestine, implying that decreased GLP1 levels were not caused by the changes in L cell intensity. Instead, the small intestinal m6A level as well as the expression of known "writers", mettl3/14 and wtap, were found to be positively correlated with the expression of Gcg and Pc3. Fecal microbiota transplantation with feces from normal and obese mice daily to antibiotic-treated mice revealed that dysbiosis in diet-induced obesity was sufficient to reduce serum GLP1, small intestinal m6A level, and intestinal expressions of Gcg, Pc3, and writer genes (mettl3/14, wtap). However, as the most direct and universal methyl donor, the production of fecal S-adenosylmethionine was neither affected by the different dietary patterns nor their shaped microbiota. These results suggested that microbial modulation of the epitranscriptome may be involved in regulating GLP1 expression, and highlighted epitranscriptomic modifications as an additional level of interaction between diet and individual health.

From probiotics to postbiotics: Concepts and applications

In recent years, the important role of gut microbiota in promoting animal health and regulating immune function in livestock and poultry has been widely reported. The issue of animal health problems causes significant economic losses each year. Probiotics and postbiotics have been widely developed as additives due to their beneficial effects in balancing host gut microbiota, enhancing intestinal epithelial barrier, regulating immunity, and whole‐body metabolism. Probiotics and postbiotics are composed of complex ingredients, with different components and compositions having different effects, requiring classification for discussing their mechanisms of action. Probiotics and postbiotics have considerable prospects in preventing various diseases in the livestock industry and animal feed and medical applications. This review highlights the application value of probiotics and postbiotics as potential probiotic products, emphasizing their concept, mechanism of action, and application, to improve the productivity of livestock and poultry.

Immunological mechanisms of inflammatory diseases caused by gut microbiota dysbiosis: A review

The gut microbiota is indispensable for maintaining host health by enhancing the host's digestive capacity, safeguarding the intestinal epithelial barrier, and preventing pathogen invasion. Additionally, the gut microbiota exhibits a bidirectional interaction with the host immune system and promotes the immune system of the host to mature. Dysbiosis of the gut microbiota, primarily caused by factors such as host genetic susceptibility, age, BMI, diet, and drug abuse, is a significant contributor to inflammatory diseases. However, the mechanisms underlying inflammatory diseases resulting from gut microbiota dysbiosis lack systematic categorization. In this study, we summarize the normal physiological functions of symbiotic microbiota in a healthy state and demonstrate that when dysbiosis occurs due to various external factors, the normal physiological functions of the gut microbiota are lost, leading to pathological damage to the intestinal lining, metabolic disorders, and intestinal barrier damage. This, in turn, triggers immune system disorders and eventually causes inflammatory diseases in various systems. These discoveries provide fresh perspectives on how to diagnose and treat inflammatory diseases. However, the unrecognized variables that might affect the link between inflammatory illnesses and gut microbiota, need further studies and extensive basic and clinical research will still be required to investigate this relationship in the future.

Alleviative Effect of Probiotic Ferment on Lawsonia intracellularis Infection in Piglets

(1) Background: Lawsonia intracellularis (LI) is an obligate intracellular Gram-negative bacterium that causes porcine ileitis. Pigs infected with LI have severe ileal lesions and show symptoms of diarrhea, indigestion, and growth retardation. Previous studies found that probiotic ferment (FAM) improved the growth performance, gut barrier, and function in piglets. Therefore, we aimed to reveal the mechanism that FAM alleviates negative performance in LI-challenged piglets by characterizing the changes in intestinal integrity, function, and gut microbiota following FAM supplementation. (2) Methods: Twenty-four healthy piglets were randomly allotted to four treatments. Three groups were challenged with LI; both FAM addition and vaccination were performed to explore their positive effects on LI-infected piglets. (3) Results: Piglets infected with LI showed lower growth performance and typical pathological symptoms. Moreover, microscopic images showed that observed intestinal morphological damage could be repaired by FAM and vaccine. To explore the digestion of nutrients in piglets, both digestive enzyme activity and ileal transporter expression were performed to reveal the promoting effect of additives. Reduction of LI colonization intervention by FAM could also ameliorate abnormal differentiation and function of intestinal epithelial cells and alleviate severe inflammatory responses in piglets. Regarding the gut microbiota, both the structure and function of the ileal and colonic microbiota were altered following FAM supplementation. (4) Conclusions: In conclusion, probiotic ferment can reduce the colonization of LI in the ileum, improve intestinal damage, barrier function and microbiota structure, and enhance digestive enzyme activity and nutrient transport proteins expression, thereby improving piglet growth performance, which has the effect of preventing ileitis in pigs.

Gut microbes influence the development of central nervous system disorders through epigenetic inheritance

Central nervous system (CNS) disorders, such as depression, anxiety, and Alzheimer's disease (AD), affect quality of life of patients and pose significant economic and social burdens worldwide. Due to their obscure and complex pathogeneses, current therapies for these diseases have limited efficacy. Over the past decade, the gut microbiome has been shown to exhibit direct and indirect influences on the structure and function of the CNS, affecting multiple pathological pathways. In addition to the direct interactions between the gut microbiota and CNS, the gut microbiota and their metabolites can regulate epigenetic processes, including DNA methylation, histone modification, and regulation of non-coding RNAs. In this review, we discuss the tripartite relationship among gut microbiota, epigenetic inheritance, and CNS disorders. We suggest that gut microbes and their metabolites influence the pathogenesis of CNS disorders at the epigenetic level, which may inform the development of effective therapeutic strategies for CNS disorders.

Probiotics and Commensal Bacteria Metabolites Trigger Epigenetic Changes in the Gut and Influence Beneficial Mood Dispositions

The effect of the intestinal microbiome on the gut-brain axis has received considerable attention, strengthening the evidence that intestinal bacteria influence emotions and behavior. The colonic microbiome is important to health and the pattern of composition and concentration varies extensively in complexity from birth to adulthood. That is, host genetics and environmental factors are complicit in shaping the development of the intestinal microbiome to achieve immunological tolerance and metabolic homeostasis from birth. Given that the intestinal microbiome perseveres to maintain gut homeostasis throughout the life cycle, epigenetic actions may determine the effect on the gut-brain axis and the beneficial outcomes on mood. Probiotics are postulated to exhibit a range of positive health benefits including immunomodulating capabilities. Lactobacillus and Bifidobacterium are genera of bacteria found in the intestines and so far, the benefits afforded by ingesting bacteria such as these as probiotics to people with mood disorders have varied in efficacy. Most likely, the efficacy of probiotic bacteria at improving mood has a multifactorial dependency, relying namely on several factors that include the agents used, the dose, the pattern of dosing, the pharmacotherapy used, the characteristics of the host and the underlying luminal microbial environment (e.g., gut dysbiosis). Clarifying the pathways linking probiotics with improvements in mood may help identify the factors that efficacy is dependent upon. Adjunctive therapies with probiotics for mood disorders could, through DNA methylation molecular mechanisms, augment the intestinal microbial active cohort and endow its mammalian host with important and critical co-evolutionary redox signaling metabolic interactions, that are embedded in bacterial genomes, and that in turn can enhance beneficial mood dispositions.

Multi-omics insights into the interplay between gut microbiota and colorectal cancer in the "microworld" age

Colorectal cancer (CRC) is a multifactorial heterogeneous disease largely due to both genetic predisposition and environmental factors including the gut microbiota, a dynamic microbial ecosystem inhabiting the gastrointestinal tract. Elucidation of the molecular mechanisms by which the gut microbiota interacts with the host may contribute to the pathogenesis, diagnosis, and promotion of CRC. However, deciphering the influence of genetic variants and interactions with the gut microbial ecosystem is rather challenging. Despite recent advancements in single omics analysis, the application of multi-omics approaches to integrate multiple layers of information in the microbiome and host to introduce effective prevention, diagnosis, and treatment strategies is still in its infancy. Here, we integrate host- and microbe-based multi-omics studies, respectively, to provide a strategy to explore potential causal relationships between gut microbiota and colorectal cancer. Specifically, we summarize the recent multi-omics studies such as metagenomics combined with metabolomics and metagenomics combined with genomics. Meanwhile, the sample size and sample types commonly used in multi-omics research, as well as the methods of data analysis, were also generalized. We highlight multiple layers of information from multi-omics that need to be verified by different types of models. Together, this review provides new insights into the clinical diagnosis and treatment of colorectal cancer patients.

Association between Intestinal Microecological Changes and Atherothrombosis

Atherosclerosis (AS) is a chronic inflammatory disease of large- and medium-sized arteries that causes ischemic heart disease, strokes, and peripheral vascular disease, collectively called cardiovascular disease (CVD), and is the leading cause of CVD resulting in a high rate of mortality in the population. AS is pathological by plaque development, which is caused by lipid infiltration in the vessel wall, endothelial dysfunction, and chronic low-grade inflammation. Recently, more and more scholars have paid attention to the importance of intestinal microecological disorders in the occurrence and development of AS. Intestinal G-bacterial cell wall lipopolysaccharide (LPS) and bacterial metabolites, such as oxidized trimethylamine (TMAO) and short-chain fatty acids (SCFAs), are involved in the development of AS by affecting the inflammatory response, lipid metabolism, and blood pressure regulation of the body. Additionally, intestinal microecology promotes the progression of AS by interfering with the normal bile acid metabolism of the body. In this review, we summarize the research on the correlation between maintaining a dynamic balance of intestinal microecology and AS, which may be potentially helpful for the treatment of AS.

Gut microbiota mediates the anti-colitis effects of polysaccharides derived from Rhopilema esculentum Kishinouye in mice

Ulcerative colitis (UC) is closely associated with the disturbance of gut microbiota. Crude polysaccharide-rich extract from Rhopilema esculentum Kishinouye has been proven to alleviate dextran sulfate sodium (DSS)-triggered colitis. However, it remains unclear whether the polysaccharides from Rhopilema esculentum (REP) in the extract play a predominant role in ameliorating colitis and whether gut microbiota mediates the beneficial effect of REP. Herein, we aimed to investigate the anti-colitis effects of REP and its mechanisms and to explore the role of REP-modulated gut microbiota in alleviating colitis in mice. Oral REP supplementation ameliorated the symptoms, inflammatory responses, colonic damage and gut microbial dysbiosis in colitic mice. REP significantly enriched SCFA-producing bacteria such as Roseburia and probiotics such as Bifidobacterium and restored the level of SCFAs especially butyric acid and propionic acid. Next, we found that transplantation of microbiota from REP-treated mice alleviated DSS-induced acute colitis, evidenced by improved gut barrier integrity and lower inflammation compared with mice receiving microbiota from control mice. Notably, dramatically enriched Bifidobacterium, Faecalibaculum and SCFA-producing bacteria including Butyricicoccus and Roseburia were found in mice receiving microbiota from the REP-treated donor mice. Lastly, the protective effect of REP supplementation on colitis was abolished in the antibiotic-treated mice. Overall, our findings suggest that REP could alleviate DSS-induced colitis in mice by regulating the imbalance of the microbiome. The polysaccharides of Rhopilema esculentum Kishinouye have the potential to be developed into promising prebiotic agents for rectifying dysbiosis of gut microbiota and preventing UC.

YTHDF1 Attenuates TBI-Induced Brain-Gut Axis Dysfunction in Mice

The brain-gut axis (BGA) is a significant bidirectional communication pathway between the brain and gut. Traumatic brain injury (TBI) induced neurotoxicity and neuroinflammation can affect gut functions through BGA. N⁶-methyladenosine (m⁶A), as the most popular posttranscriptional modification of eukaryotic mRNA, has recently been identified as playing important roles in both the brain and gut. However, whether m⁶A RNA methylation modification is involved in TBI-induced BGA dysfunction is not clear. Here, we showed that YTHDF1 knockout reduced histopathological lesions and decreased the levels of apoptosis, inflammation, and oedema proteins in brain and gut tissues in mice after TBI. We also found that YTHDF1 knockout improved fungal mycobiome abundance and probiotic (particularly Akkermansia) colonization in mice at 3 days post-CCI. Then, we identified the differentially expressed genes (DEGs) in the cortex between YTHDF1-knockout and WT mice. These genes were primarily enriched in the regulation of neurotransmitter-related neuronal signalling pathways, inflammatory signalling pathways, and apoptotic signalling pathways. This study reveals that the ITGA6-mediated cell adhesion molecule signalling pathway may be the key feature of m⁶A regulation in TBI-induced BGA dysfunction. Our results suggest that YTHDF1 knockout could attenuate TBI-induced BGA dysfunction.

The Interaction between Flavonoids and Intestinal Microbes: A Review

In recent years, research on the interaction between flavonoids and intestinal microbes have prompted a rash of food science, nutriology and biomedicine, complying with future research trends. The gut microbiota plays an essential role in the maintenance of intestinal homeostasis and human health, but once the intestinal flora dysregulation occurs, it may contribute to various diseases. Flavonoids have shown a variety of physiological activities, and are metabolized or biotransformed by gut microbiota, thereby producing new metabolites that promote human health by modulating the composition and structure of intestinal flora. Herein, this review demonstrates the key notion of flavonoids as well as intestinal microbiota and dysbiosis, aiming to provide a comprehensive understanding about how flavonoids regulate the diseases by gut microbiota. Emphasis is placed on the microbiota-flavonoid bidirectional interaction that affects the metabolic fate of flavonoids and their metabolites, thereby influencing their metabolic mechanism, biotransformation, bioavailability and bioactivity. Potentially by focusing on the abundance and diversity of gut microbiota as well as their metabolites such as bile acids, we discuss the influence mechanism of flavonoids on intestinal microbiota by protecting the intestinal barrier function and immune system. Additionally, the microbiota-flavonoid bidirectional interaction plays a crucial role in regulating various diseases. We explain the underlying regulation mechanism of several typical diseases including gastrointestinal diseases, obesity, diabetes and cancer, aiming to provide a theoretical basis and guideline for the promotion of gastrointestinal health as well as the treatment of diseases.

Early life gut microbiota: Consequences for health and opportunities for prevention

The gut microbiota influences many aspects of the host, including immune system maturation, nutrient absorption and metabolism, and protection from pathogens. Increasing evidences from cohort and animal studies indicate that changes in the gut microbiota early in life increases the risk of developing specific diseases early and later in life. Therefore, it is becoming increasingly important to identify specific disease prevention or therapeutic solutions targeting the gut microbiota, especially during infancy, which is the window of the human gut microbiota establishment process. In this review, we provide an overview of current knowledge concerning the relationship between disturbances in the gut microbiota early in life and health consequences later in life (e.g., necrotizing enterocolitis, celiac disease, asthma, allergies, autism spectrum disorders, overweight/obesity, diabetes and growth retardation), with a focus on changes in the gut microbiota prior to disease onset. In addition, we summarize and discuss potential microbiota-based interventions early in life (e.g., diet adjustments, probiotics, prebiotics, fecal microbiota transplantation, environmental changes) to promote health or prevent the development of specific diseases. This knowledge should aid the understanding of early life microbiology and inform the development of prediction and prevention measures for short- and long-term health disorders based on the gut microbiota.

Gut microbiota supports male reproduction via nutrition, immunity, and signaling

Gut microbiota (GM) is a major component of the gastrointestinal tract. Growing evidence suggests that it has various effects on many distal organs including the male reproductive system in mammals. GM and testis form the gut-testis axis involving the production of key molecules through microbial metabolism or de novo synthesis. These molecules have nutrition, immunity, and hormone-related functions and promote the male reproductive system via the circulatory system. GM helps maintain the integral structure of testes and regulates testicular immunity to protect the spermatogenic environment. Factors damaging GM negatively impact male reproductive function, however, the related mechanism is unknown. Also, the correlation between GM and testis remains to be yet investigated. This review discusses the complex influence of GM on the male reproductive system highlighting the impact on male fertility.

Characterization of Lactic Acid-Producing Bacteria Isolated from Rumen: Growth, Acid and Bile Salt Tolerance, and Antimicrobial Function

Lactic acid bacteria are some of the dominant bacteria in the rumen, and they have a high ability for lactic acid production. The present study aimed to screen and evaluate the performance of culturable rumen bacteria from Chinese Holstein dairy cows as a potential probiotic or inoculant for silage production, in order to isolate ruminal lactic acid bacteria and evaluate their potential as probiotics. Three strains of Enterococcus avium (E. avium, EA1-3); three strains of Streptococcus lutetiensis (S. lutetiensis, SL1-3); and six strains of Streptococcus equinus (S. equinus, SE1-6) were successfully identified from the rumen fluid using modified De Man Rogosa sharp medium supplemented with 0.325% lactic acid. E. avium, S. lutetiensis and S. equinus are clustered in the phylogenetic tree. All the 12 Gram-positive strains reached the plateau growth phase in 6–10 h, with an OD600 at about 1.8. Both gas and acid accumulation reached plateaus at about 10–12 h in all strains, and S. equinus showed the strongest capacity. The highest lactic acid accumulation was detected in S. equinus broth (up to 219.77 μmol/L). The growth of all isolates was inhibited at pH 4.0, and EA2, SL1, SL2, SL3 and SE2 were tolerant to 0.1%, 0.2% and 0.3% bile salt. In addition, the supernatants of the strains had inhibitory effects on Escherichia coli and Staphylococcus aureus. Specifically, the S. equinus strains exhibited the strongest inhibition of the pathogens. In conclusion, these 12 strains had good potential as silage inoculants or probiotics for edible animals, especially S. equinus.

The Potential Role of m6A in the Regulation of TBI-Induced BGA Dysfunction

The brain–gut axis (BGA) is an important bidirectional communication pathway for the development, progress and interaction of many diseases between the brain and gut, but the mechanisms remain unclear, especially the post-transcriptional regulation of BGA after traumatic brain injury (TBI). RNA methylation is one of the most important modifications in post-transcriptional regulation. N6-methyladenosine (m⁶A), as the most abundant post-transcriptional modification of mRNA in eukaryotes, has recently been identified and characterized in both the brain and gut. The purpose of this review is to describe the pathophysiological changes in BGA after TBI, and then investigate the post-transcriptional bidirectional regulation mechanisms of TBI-induced BGA dysfunction. Here, we mainly focus on the characteristics of m⁶A RNA methylation in the post-TBI BGA, highlight the possible regulatory mechanisms of m⁶A modification in TBI-induced BGA dysfunction, and finally discuss the outcome of considering m⁶A as a therapeutic target to improve the recovery of the brain and gut dysfunction caused by TBI.

Diet-gut microbiota-epigenetics in metabolic diseases: From mechanisms to therapeutics

The prevalence of metabolic diseases, including obesity, dyslipidemia, type 2 diabetes mellitus (T2DM), and non-alcoholic fatty liver disease (NAFLD), is a severe burden in human society owing to the ensuing high morbidity and mortality. Various factors linked to metabolic disorders, particularly environmental factors (such as diet and gut microbiota) and epigenetic modifications, contribute to the progression of metabolic diseases. Dietary components and habits regulate alterations in gut microbiota; in turn, microbiota-derived metabolites, such as short-chain fatty acids (SCFAs), are influenced by diet. Interestingly, diet-derived microbial metabolites appear to produce substrates and enzymatic regulators for epigenetic modifications (such as DNA methylation, histone modifications, and non-coding RNA expression). Epigenetic changes mediated by microbial metabolites participate in metabolic disorders via alterations in intestinal permeability, immune responses, inflammatory reactions, and insulin resistance. In addition, microbial metabolites can trigger inflammatory immune responses and microbiota dysbiosis by directly binding to G-protein-coupled receptors (GPCRs). Hence, diet-gut microbiota-epigenetics may play a role in metabolic diseases. However, their complex relationships with metabolic diseases remain largely unknown and require further investigation. This review aimed to elaborate on the interactions among diet, gut microbiota, and epigenetics to uncover the mechanisms and therapeutics of metabolic diseases.

Limosilactobacillus reuteri SLZX19-12 Protects the Colon from Infection by Enhancing Stability of the Gut Microbiota and Barrier Integrity and Reducing Inflammation

Limosilactobacillus reuteri plays an important role in regulating intestinal functions and maintaining barrier integrity in animals. In this study, Limosilactobacillus reuteri strain SLZX19-12 was isolated from the fecal microbiota of Tibetan pigs, and it was found that this strain is sensitive to common antibiotics and has strong resistance to stress. Upon being administered by gavage at different doses, including low, medium, and high doses, for 14 days, Limosilactobacillus reuteri SLZX19-12 may enhance the intestinal barrier. After administration of a high dose of SLZX19-12, mice were challenged with Salmonella enterica serovar Typhimurium SL1344. Infection with Salmonella Typhimurium SL1344 led to disordered colonic microbiotas, colonic inflammation through the S100A8/S100A9-NF-κB pathway and potential apoptosis, and translocation of pathogens to parenteral visceral organs in mice. However, the mice pretreated with Limosilactobacillus reuteri SLZX19-12 showed lower loads of Salmonella in visceral organs, less colonic inflammation, and higher barrier integrity. More importantly, the administration of strain SLZX19-12 resulted in a more stable microbiota structure of the colon, in which the abundance of Alloprevotella was greatly enhanced. Therefore, this study suggests that Limosilactobacillus reuteri SLZX19-12 can protect the colon from infection by enhancing the stability of gut microbiota and barrier integrity and reducing inflammation. IMPORTANCE The use of antibiotics to treat bacterial infections leads to a series of side effects. As an alternative method, the biocontrol strategy, which uses probiotics to suppress pathogens, is considered a potential way to deal with bacterial infections in gut. However, there are few probiotics that are currently safe and can protect against infection. In this study, Limosilactobacillus reuteri strain SLZX19-12 was obtained from Tibetan pigs, which have higher resistance to infection. This strain is sensitive to conventional antibiotics, secretes a wide spectrum of enzymes, and also promotes the intestinal barrier function in mice. In addition, Limosilactobacillus reuteri SLZX19-12 can promote the stability of the gut microbiota to avoid or alleviate the occurrence or development of foodborne infections.

Anthocyanins in Chronic Diseases: The Power of Purple

Anthocyanins are mainly purple-coloured phenolic compounds of plant origin that as secondary metabolites are important in plant survival. Understanding their health benefits in humans requires sourcing these unstable compounds in sufficient quantities at a reasonable cost, which has led to improved methods of extraction. Dark-coloured fruits, cereals and vegetables are current sources of these compounds. The range of potential sustainable sources is much larger and includes non-commercialised native plants from around the world and agri-waste containing anthocyanins. In the last 5 years, there have been significant advances in developing the therapeutic potential of anthocyanins in chronic human diseases. Anthocyanins exert their beneficial effects through improvements in gut microbiota, oxidative stress and inflammation, and modulation of neuropeptides such as insulin-like growth factor-1. Their health benefits in humans include reduced cognitive decline; protection of organs such as the liver, as well as the cardiovascular system, gastrointestinal tract and kidneys; improvements in bone health and obesity; and regulation of glucose and lipid metabolism. This review summarises some of the sources of anthocyanins and their mechanisms and benefits in the treatment of chronic human diseases.

IgE-Mediated food allergy: Current diagnostic modalities and novel biomarkers with robust potential

Food allergy (FA) is a serious public health issue afflicting millions of people globally, with an estimated prevalence ranging from 1-10%. Management of FA is challenging due to overly restrictive diets and the lack of diagnostic approaches with high accuracy and prediction. Although measurement of serum-specific antibodies combined with patient medical history and skin prick test is a useful diagnostic tool, it is still an imprecise predictor of clinical reactivity with a high false-positive rate. The double-blind placebo-controlled food challenge represents the gold standard for FA diagnosis; however, it requires large healthcare and involves the risk of acute onset of allergic reactions. Improvement in our understanding of the molecular mechanism underlying allergic disease pathology, development of omics-based methods, and advances in bioinformatics have boosted the generation of a number of robust diagnostic biomarkers of FA. In this review, we discuss how traditional diagnostic modalities guide appropriate diagnosis and management of FA in clinical practice, as well as uncover the potential of the latest biomarkers for the diagnosis, monitoring, and prediction of FA. We also raise perspectives for precise and targeted medical intervention to fill the gap in the diagnosis of FA.

Mechanisms Involved in Gut Microbiota Regulation of Skeletal Muscle

Skeletal muscle is one of the largest organs in the body and is essential for maintaining quality of life. Loss of skeletal muscle mass and function can lead to a range of adverse consequences. The gut microbiota can interact with skeletal muscle by regulating a variety of processes that affect host physiology, including inflammatory immunity, protein anabolism, energy, lipids, neuromuscular connectivity, oxidative stress, mitochondrial function, and endocrine and insulin resistance. It is proposed that the gut microbiota plays a role in the direction of skeletal muscle mass and work. Even though the notion of the gut microbiota-muscle axis (gut-muscle axis) has been postulated, its causal link is still unknown. The impact of the gut microbiota on skeletal muscle function and quality is described in detail in this review.

Influence of Natural Polysaccharides on Intestinal Microbiota in Inflammatory Bowel Diseases: An Overview

The incidence of inflammatory bowel disease (IBD) has increased in recent years. Considering the potential side effects of conventional drugs, safe and efficient treatment methods for IBD are required urgently. Natural polysaccharides (NPs) have attracted considerable attention as potential therapeutic agents for IBD owing to their high efficiency, low toxicity, and wide range of biological activities. Intestinal microbiota and their fermentative products, mainly short-chain fatty acids (SCFAs), are thought to mediate the effect of NPs in IBDs. This review explores the beneficial effects of NPs on IBD, with a special focus on the role of intestinal microbes. Intestinal microbiota exert alleviation effects via various mechanisms, such as increasing the intestinal immunity, anti-inflammatory activities, and intestinal barrier protection via microbiota-dependent and microbiota-independent strategies. The aim of this paper was to document evidence of NP–intestinal microbiota-associated IBD prevention, which would be helpful for guidance in the treatment and management of IBD.