Exposure to acute hypoxia severely impairs skeletal muscle function, but the temporal dynamics and underlying mechanisms remain unclear. Male C57BL/6 mice were exposed to normobaric hypoxia (FiO2 = 11.8

Currently, atherosclerotic cardiovascular disease (ASCVD) is the primary cause of mortality globally. Meanwhile, accumulating evidence continues to implicate gut microbiota and the associated metabolites in the pathogenesis and progression of atherosclerosis. Red yeast rice (RYR), a traditional functional food, contains monacolin K as the primary bioactive component, which exerts statin-like lipid-lowering effects. Thus, RYR plays a protective role in regulating lipid metabolism and preventing ASCVD through multiple pathways, including improving endothelial dysfunction, attenuating oxidative stress, and inhibiting inflammatory responses. Therefore, this review summarizes current evidence regarding the regulatory effects of RYR and the associated preparations on hyperlipidemia and ASCVD. Furthermore, we highlight the protective role of RYR in the management of hyperlipidemia, with particular emphasis on the capacity of RYR to modulate the gut microbiota and the associated metabolites, thereby exerting anti-atherosclerotic effects. By elucidating the intricate interactions between RYR and the gut microbiota, this review provides novel insights into the therapeutic potential of RYR and reveals possible roles for the gut microbiota in ASCVD prevention.

Ulcerative colitis (UC), a common inflammatory bowel disease (IBD), is characterized by chronic mucosal inflammation. Our previous work established a link between cellular senescence and UC, suggesting that ameliorating cell senescence could be a therapeutic strategy for UC. In this study, we identified dehydrodiisoeugenol (DDIE) as an anti-senescence drug through screening in a DSS-induced colonic epithelial cell senescence model. In a DSS-induced acute mouse model of UC, DDIE effectively suppressed colonic senescence and significantly alleviated UC. Network pharmacology, colonic tissue transcriptomic analysis, and Western blot assays indicated that DDIE's therapeutic effects in UC are associated with the AKT and GSK3B pathways. Subsequent cellular blocking experiments utilizing the AKT activator insulin and the GSK3B inhibitor BIO confirmed that activating AKT or inhibiting GSK3B reversed the anti-senescence and anti-inflammatory effects of DDIE. Our findings demonstrate that DDIE treats UC by inhibiting AKT and activating GSK3B, thereby suppressing cellular senescence and restoring the intestinal barrier. This research offers a novel therapeutic strategy for UC from the perspective of anti-cellular senescence.

The mechanisms by which microbiota from disease-resistant populations or animals improve intestinal immune defense remain incompletely elucidated. Tibetan pig, a renowned disease-resistant breed, serve as a valuable research subject for the health of humans and economic animals. In this study, fecal microbiota transplantation from Tibetan piglets into mice conferred enhanced resistance to C. rodentium DBS100. Further microbiota profiling and metabolomics analysis showed this protection may be partly ascribed to C. butyricum SLZX19-05 in recipients’ colon. Administration of C. butyricum SLZX19-05 to germ-free mice resulted in the significantly increased lysozyme expression within colonic macrophages, subsequently bolstering the resistance to C. rodentium infection. In mice and piglets, this C. butyricum similarly elevated the lysozyme level in colon and decreased diarrhea incidence. Conversely, lyz1-knockout heightened mice's susceptibility to C. rodentium, highlighting lysozyme’s critical role in immune defense. Mechanistically, this study systematically revealed that C. butyricum enhanced lysozyme expression by inhibiting mTORC1-HDAC3/8 pathway, leading to the increased H4K31 Crotonylation (H4K31Cr) and openness of an upstream region of lyz1 promoter via butyrate in macrophages. Additionally, H4K31-mutant mice showed the leukopenia, further validating the significance of H4K31Cr in immune regulation. Collectively, mTORC1-HDAC3/8-H4K31Cr pathway is a key mechanism by which butyrate-producing commensal bacteria enhance immune defense in gut. This discovery provides a novel foundation for the screening and application of the next generation of butyrate-producing probiotics.

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by difficulties in social interaction and communication, repetitive and stereotyped behaviors, restricted interests, and sensory abnormalities. Its etiology is influenced by both genetic and environmental factors, with no definitive cause identified and no specific pharmacological treatments available, posing a significant burden on patients’ families and society. In recent years, research has discovered that gut microbiota dysbiosis plays a crucial role in the pathogenesis of ASD. The gut microbiota can influence brain function and behavior through the gut-brain axis via the nervous system, immune system, and metabolic pathways. On the one hand, specific gut microbes such as Clostridium and Prevotella species are found to be abnormal in ASD patients, and their metabolic products, like short-chain fatty acids, serotonin, and GABA, are also involved in the pathological process of ASD. On the other hand, ASD patients exhibit immune system dysfunction, with gut immune cells and related cytokines affecting neural activities in the brain. Currently, intervention methods targeting the gut microbiota, such as probiotics, prebiotics, and fecal microbiota transplantation, have shown some potential in improving ASD symptoms. However, more studies are needed to explore their long-term effects and optimal treatment protocols. This paper reviews the mechanisms and interrelationships among gut microbiota, immune system, and nervous system in ASD and discusses the challenges and future directions of existing research, aiming to provide new insights for the prevention and treatment of ASD.

Objective:Age-related intestinal barrier dysfunction is a key factor leading to systemic inflammation. Previous studies have found that methionine and its metabolites play a role in anti-aging, but the specific effects on the intestines of aging mice remain unclear. This study aims to explore the effects of different doses of methionine in the diet on intestinal integrity and gut microbiota, and to clarify its potential mechanism in a mouse model of accelerated aging (SAMP8). Method:SAMP8 mice were selected and divided into three groups, each receiving a Methionine-restricted diet (0.17%Met), normal (0.86%Met), or Methionine-supplemented diet (1.64%Met) for 4 weeks. And SAMP1 mice were used as the control. The intestinal barrier function was evaluated by detecting the levels of LPS, IFABP and Zonulin in serum through ELISA. The integrity of colon tissue, the expression of tight junction proteins (ZO-1 and Occludin) and inflammatory signaling pathways (TLR4/NF-κB) were evaluated by histology, immunofluorescence and Western blot. The composition of the gut microbiota was analyzed by 16S rRNA sequencing, and the levels of hydrogen sulfide (H₂S), sulfomucin in the intestine and the expression of genes related to mucus sulfation were quantitatively detected. Result:Methionine-supplemented diet (1.64%Met) significantly improved intestinal aging. Specifically, it is manifested as reducing the expression of cellular senescence markers p16 and p21, lowering the levels of LPS, IFABP and zonulin in serum, restoring the disordered colon structure, and upregulating the expression of tight junction proteins (ZO-1, Occludin). The pro-inflammatory effect of a methionine-supplemented diet on the TLR4/NF-κB pathway reduces the production of H₂S in the intestine. In addition, Methionine-supplemented diet reshaped the gut microbiota, increasing the abundance of beneficial bacterial genera (such as Parabacteroides) while reducing the abundance of H₂S-producing bacteria (such as norank_f__Desulfovibrionaceae). This change in the microbial community is closely related to the concentration of methionine intake and also associated with the recovery of intestinal sulfation, manifested as an increase in the expression of sulfattransferases (such as Papss2) and an increase in the production of sulfomucin. On the contrary, a methionine-restricted diet increased the abundance of norank_f__Desulfovibrionaceae, exacerbating gut microbiota imbalance and barrier dysfunction. Conclusion:A methionine-supplemented diet within the safe range significantly alleviates aging-induced intestinal barrier dysfunction by regulating the gut microbiota, inhibiting H₂S-producing bacteria, and restoring the host's intestinal sulfation capacity. A new microbiota- sulfation axis pathway was revealed, which promotes the metabolism of toxic sulfur substances related to the microbiota (such as H2S, indoxyl sulfate, etc.), and methionine supplementation was proposed as a promising nutritional strategy to promote intestinal health and alleviate aging-related pathological changes.

Autism Spectrum Disorder (ASD) manifests as a group of neurodevelopmental disorders with high clinical and genetic heterogeneity, characterized by core features including social communication deficits, repetitive behaviors, and restricted interests. Current research primarily focuses on genetic variations, immune dysregulation, synaptic dysfunction, and gene–environment interactions. Nowadays, accumulating evidence indicates that maternal gut microbiota dysbiosis, induced by high-fat diets, antibiotic overuse, and urbanization, significantly correlates with abnormal fetal neurodevelopment and increased ASD risk. This review systematically delineates three transplacental mechanisms whereby maternal dysbiosis regulates fetal neurodevelopment: Metabolite-mediated pathways, Immune pathway activation, and Epigenetic reprogramming. Meanwhile, the key translational challenges are highlighted. At last, metagenomics-metabolomics-fetal neuroimaging, Development of microbiota metabolite-treated brain organoids, and Artificial Intelligence-driven (AI-driven) probiotic screening were proposed as research directions in future.

The unprecedented rise in global ambient temperatures in the last decade has significantly impacted human health, yet how heat exposure affects the development of sarcopenia remains enigmatic. Here, we demonstrate that chronic heat exposure induces skeletal muscle volume loss, leading to muscle strength and functional decline in mice. The microbiota composition of heat-exposed mice was analyzed using 16S ribosomal DNA analysis. Liquid chromatography-mass spectrometry (LC-MS) was used to explore the effects of heat exposure on the blood metabolome and to further analyze the correlation between blood metabolism and gut microbiota. Transplantation of microbiota from heat-exposed mice to germ-free mice was sufficient to increase adverse effects on skeletal muscle function in the host. Mechanistically, using an untargeted metabolomics strategy, we reveal that altered gut microbiota due to high temperatures is associated with elevated serum levels of homocitrulline. Homocitrulline causes mitochondrial dysfunction in myocytes by exacerbating ferroptosis levels. And Nrf2 activator (Oltipraz) supplementation alleviates muscle atrophy and dysfunction induced by heat exposure. Our findings reveal the detrimental effects of heat exposure on muscle function and provide new strategies for treating sarcopenia.

Exhaustive exercise is known to induce muscle damage characterized by inflammation and oxidative stress. Although “regular” and “weekend warrior” exercise regimens have been shown to confer comparable health benefits in human studies, such as reduced risks of all-cause, cardiovascular disease (CVD), and cancer mortality, their differential impacts on muscle damage post-exhaustive exercise remain unclear. This study aimed to compare the effects of long-term, moderate-intensity (LTMI) and short-term, high-intensity (STHI) training modalities, matched for total exercise volume, on gut microbiota, short-chain fatty acids (SCFAs), and exhaustive exercise-induced muscle damage in mice, as well as to evaluate the correlation between these factors. LTMI is considered a regular exercise regimen, while STHI shares some similarities with the “weekend warrior” pattern, such as promoting exercise intensity and condensing training sessions into a short period. Our findings indicate that LTMI training significantly enhanced the abundance of SCFA-producing bacteria, including Akkermansia, Prevotellaceae_NK3B31_group, Odoribacter, Alistipes, and Lactobacillus, thereby increasing SCFA levels and attenuating muscle damage following exhaustive swimming. In contrast, STHI training increased the abundance of opportunistic pathogens such as Staphylococcus and Bilophila, without altering SCFA levels, and was associated with exacerbated muscle damage. Moreover, we observed a significant negative correlation between the abundance of SCFA-producing bacteria and SCFA levels with the expression of inflammatory cytokines in the muscle of mice post-exhaustive exercise. Conversely, the abundance of Staphylococcus and Bilophila showed a notable positive correlation with these cytokines. Additionally, the effects of LTMI and STHI on exhaustive exercise-induced muscle damage were transmissible to untrained mice via fecal microbiota transplantation, suggesting that gut microbiota changes induced by these training modalities may contribute to their contrasting impacts on muscle damage. These results underscore the significance of selecting an appropriate training modality prior to engaging in exhaustive exercise, with implications for athletic training and injury prevention.

Deoxynivalenol (DON) is a prevalent toxin causing severe liver damage through hepatocellular oxidative stress. However, the underlying mechanisms and effective therapeutic approaches remain unknown. Here, the unique role of the xenobiotic metabolism factor pregnane X receptor (PXR) in mediating DON-induced hepatocellular oxidative stress is investigated. Treatment with the PXR agonist 3-indole-propionic acid (IPA) alleviates DON-induced oxidative stress and liver injury both in vitro and in vivo. Mechanistically, it is discovered for the first time that PXR agonist IPA directly transactivates the m6A demethylase FTO expression, leading to site-specific demethylation and decreased abundance of YTHDC1-bound Malat1 lncRNA at single-nucleotide resolution. The diminished m6A modification of Malat1 lncRNA reduces its stability and augments antioxidant pathways governed by NRF2, consequently mitigating DON-induced liver injury. Furthermore, Malat1 knockout mice exhibit decreased DON-induced liver injury, emphasizing the role of Malat1 lncRNA in oxidative stress. Collectively, the findings establish that PXR-mediated m(6)A-dependent Malat1 lncRNA expression determines hepatocyte oxidative stress via m(6)A demethylase FTO, providing valuable insights into the potential mechanisms underlying DON-induced liver injury and offers potential therapeutic strategies for its treatment.

Objective To explore the role of indole-3-propionic acid (IPA) in the pathogenesis of metabolic associated fatty liver disease (MAFLD) induced by high-fat diet (HFD) in order to reveal the role and related mechanism of adipose tissue metabolism in the process. Methods A mouse model of MAFLD was induced by HFD. Male C57BL/6J mice (6~7 weeks old) were randomly divided into control group (CON), HFD group, and HFD+IPA intervention group (HFD+IPA). The CON group was fed with control diet, and the HFD group and HFD+IPA group were fed with 60% of high-fat diet. The experiment period was 12 weeks, and IPA was administered at 20 mg/(kg·d) for 6 weeks starting from the 7th week. The body weight and food intake of each group were monitored weekly. After the intervention, the body composition of mice was detected by animal body composition analyzer. After the mice were euthanized, the morphological and structural changes in the liver and adipose tissues were observed by HE staining, the indicators relevant to lipid metabolism in the serum, liver and adipose tissues were detected by automatic blood biochemical analyzer and biochemical kits, and the mRNA expression changes of lipid metabolism and inflammation related genes were detected by qRT-PCR. Results Compared with the CON group, the HFD group had significantly increased body weight and body fat percentage, obvious lipid deposition in the liver, obviously elevated serum alanine aminotransferase, aspartate aminotransferase, liver triglyceride and total cholesterol levels (P < 0.05), and raised mRNA levels of liver fatty acid transporter CD36 (P < 0.05), while IPA intervention significantly reversed the above changes (P < 0.05). IPA intervention significantly inhibited the HFD-induced enlargement of visceral and brown fat cells, reduced the content of visceral adipose tissue (VAT) and serum level of free fatty acids (P < 0.05), and increased the mRNA expression levels of VAT lipolysis (HSL, CGI58), browning genes (Cidea, ND5, UCP1, Prdm16) (P < 0.05), as well as those of brown adipose tissue (BAT) lipolysis (HSL, ATGL) and fatty acid beta oxidation (Cpt1a, PPARα) genes (P < 0.05). Meanwhile, the mRNA levels of TNF-α, IL-1β, CXCL1 and CCL2 in VAT and BAT were decreased after IPA intervention (P < 0.05). Conclusion IPA can improve the occurrence of MAFLD induced by HFD, and its mechanism may be closely associated with its regulation of BAT and VAT morphology, and the mRNA expression of metabolic function and inflammation related genes.

The composition of skeletal muscle fiber types affects the quality of livestock meat and human athletic performance and health. L-arginine (Arg), a semi-essential amino acid, has been observed to promote the formation of slow-twitch muscle fibers in animal models. However, the precise molecular mechanisms are still unclear. This study investigates the role of Arg in skeletal muscle fiber composition and mitochondrial function through the mTOR signaling pathway. In vivo, 4-week C56BL/6J male mice were divided into three treatment groups and fed a basal diet supplemented with different concentrations of Arg in their drinking water. The trial lasted 7 weeks. The results show that Arg supplementation significantly improved endurance exercise performance, along with increased SDH enzyme activity and upregulated expression of the MyHC I, MyHC IIA, PGC-1α, and NRF1 genes in the gastrocnemius (GAS) and quadriceps (QUA) muscles compared to the control group. In addition, Arg activated the mTOR signaling pathway in the skeletal muscle of mice. In vitro experiments using cultured C2C12 myotubes demonstrated that Arg elevated the expression of slow-fiber genes (MyHC I and Tnnt1) as well as mitochondrial genes (PGC-1α, TFAM, MEF2C, and NRF1), whereas the effects of Arg were inhibited by the mTOR inhibitor rapamycin. In conclusion, these findings suggest that Arg modulates skeletal muscle fiber type towards slow-twitch fibers and enhances mitochondrial functions by upregulating gene expression through the mTOR signaling pathway.

The study investigated the effect of pterostilbene (PTE) on intestinal glucose absorption and its underlying mechanisms in high-intensity swimming exercise (HISE)-treated mice. Male C57BL/6 mice were treated with PTE for 4 weeks and performed high-intensity swimming training in the last week. Intestinal epithelial cells (IECs) were pretreated with 0.5 and 1.0 μM PTE for 24 h before being incubated in hypoxia/reoxygenation condition. Intestinal glucose absorption was detected by using an oral glucose tolerance test and d-xylose absorption assay, and the levels of factors related to mitochondrial function and pyroptosis were measured via western blot analyses, cell mito stress test, and quantitative real-time polymerase chain reaction. In vivo and in vitro, the results showed that PTE attenuated HISE-induced intestinal glucose absorption dysfunction and pyroptosis in mice intestine. Moreover, PTE inhibited NLRP3 inflammasome and the mitochondrial homeostasis as well as the ROS accumulation in IEC in vitro. Additionally, knockdown of SIRT3, a major regulator of mitochondria function, by siRNA or inhibiting its activity by 3-TYP abolished the effects of PTE on pyroptosis, mitochondrial homeostasis, and ROS generation of IEC in vitro. Our results revealed that PTE could alleviate HISE-induced intestinal glucose absorption dysfunction associated with the inhibition of NLRP3 inflammasome-induced IECs pyroptosis.

Background: Exercise-induced gastrointestinal syndrome (GIS) has symptoms commonly induced by strenuous sports. The study aimed to determine the effect of dihydromyricetin (DHM) administration on high-intensity exercise (HIE)-induced intestinal barrier dysfunction and the underlying mechanism involved with intestinal intraepithelial lymphocytes (IELs). Methods: The HIE model was established with male C57BL/6 mice using a motorized treadmill for 2 weeks, and DHM was given once a day by oral gavage. After being sacrificed, the small intestines of the mice were removed immediately. Results: We found that DHM administration significantly suppressed HIE-induced intestinal inflammation, improved intestinal barrier integrity, and inhibited a HIE-induced increase in the number of IELs and the frequency of CD8αα+ IELs. Meanwhile, several markers associated with the activation, gut homing and immune functions of CD8αα+ IELs were regulated by DHM. Mechanistically, luciferase reporter assay and molecular docking assay showed DHM could activate the aryl hydrocarbon receptor (AhR). Conclusions: These data indicate that DHM exerts a preventive effect against HIE-induced intestinal barrier dysfunction, which is associated with the modulation of the quantity and phenotype of IELs in the small intestine. The findings provide a foundation to identify novel preventive strategies based on DHM supplementation for HIE-induced GIS.

Nutrients sensing is crucial for fundamental metabolism and physiological functions, and it is also an essential component for maintaining body homeostasis. Traditionally, basic taste receptors exist in oral cavity to sense sour, sweet, bitter, umami, salty and et al. Recent studies indicate that gut can sense the composition of nutrients by activating relevant taste receptors, thereby exerting specific direct or indirect effects. Gut taste receptors, also named as intestinal nutrition receptors, including at least bitter, sweet and umami receptors, have been considered to be activated by certain nutrients and participate in important intestinal physiological activities such as eating behavior, intestinal motility, nutrient absorption and metabolism. Additionally, gut taste receptors can regulate appetite and body weight, as well as maintain homeostasis via targeting hormone secretion or regulating the gut microbiota. On the other hand, malfunction of gut taste receptors may lead to digestive disorders, and then result in obesity, type 2 diabetes and gastrointestinal diseases. At present, researchers have confirmed that the brain-gut axis may play indispensable roles in these diseases via the secretion of brain-gut peptides, but the mechanism is still not clear. In this review, we summarize the current observation of knowledge in gut taste systems in order to shed light on revealing their important nutritional functions and promoting clinical implications.

AbstractIn 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.

Mounting evidence suggested that high loading intensity of exercise might be detrimental to human health, especially the gastrointestinal tract. Pterostilbene (PTE), derived from grapes and blueberries, might reach a high concentration of intestinal contents. Our study aimed to evaluate PTE’s ability to prevent the loss of intestinal epithelial barrier in high loading intensity of exercise. The exercise model was established by the forced running of mice. An effective HPLC-UV method was developed to quantify PTE concentration in intestinal content. The mRNA changes were detected by quantitative polymerase chain reaction (qPCR). The structure of intestinal flora was analyzed by 16S rRNA sequencing. The PTE (100 mg/kg/d) could significantly attenuate exercise-induced intestinal epithelial barrier loss. Moreover, the HPLC-UV assay showed that the PTE concentration of intestinal content could last 12 h. Furthermore, the exercise increased the abundance of Alistipes, which was related to lipopolysaccharide (LPS) production but could not be reversed by PTE intervention. Besides, cell experiments showed that PTE could promote the expression of intestinal epithelial tight junction (TJ) molecules in vitro . In conclusion, PTE has a significant interest in preventing exercise-induced intestinal damage.

Hypoxia environment has been widely used to promote exercise capacity. However, the underlying mechanisms still need to be further elucidated. In this study, mice were exposed to the normoxia environment (21% O 2 ) or hypoxia environment (16.4% O 2 ) for 4 weeks. Hypoxia-induced gut microbiota remodeling characterized by the increased abundance of Akkermansia and Bacteroidetes genera, and their related short-chain fatty acids (SCFAs) production. It was observed that hypoxia markedly improved endurance by significantly prolonging the exhaustive running time, promoting mitochondrial biogenesis, and ameliorating exercise fatigue biochemical parameters, including urea nitrogen, creatine kinase, and lactic acid, which were correlated with the concentrations of SCFAs. Additionally, the antibiotics experiment partially inhibited hypoxia-induced mitochondrial synthesis. The microbiota transplantation experiment demonstrated that the enhancement of endurance capacity induced by hypoxia was transferable, indicating that the beneficial effects of hypoxia on exercise performance were partly dependent on the gut microbiota. We further identified that acetate and butyrate, but not propionate, stimulated mitochondrial biogenesis and promoted endurance performance. Our results suggested that hypoxia exposure promoted endurance capacity partially by the increased production of SCFAs derived from gut microbiota remodeling.

Exercise-induced physical endurance enhancement and skeletal muscle remodeling can prevent and delay the development of multiple diseases, especially metabolic syndrome. Herein, the study explored the association between glucagon-like peptide-1 (GLP-1) secretion and exercise, and its effect on skeletal muscle remodeling to enhance endurance capacity. We found both acute exercise and short-term endurance training significantly increased the secretion of GLP-1 in mice. Recombinant adeno-associated virus (AAV) encoding Gcg (proglucagon) was used to induce the overexpression of GLP-1 in skeletal muscle of mice. Overexpression of GLP-1 in skeletal muscle enhanced endurance capacity. Meanwhile, glycogen synthesis, glucose uptake, type I fibers proportion, and mitochondrial biogenesis were augmented in GLP-1-AAV skeletal muscle. Furthermore, the in vitro experiment showed that exendin-4 (a GLP-1 receptor agonist) treatment remarkably promoted glucose uptake, type I fibers formation, and mitochondrial respiration. Mechanistically, the knockdown of AMPK could reverse the effects imposed by GLP-1R activation in vitro. Taken together, these results verify that GLP-1 regulates skeletal muscle remodeling to enhance exercise endurance possibly via GLP-1R signaling-mediated phosphorylation of AMPK.