Prebiotic Inulin and Sodium Butyrate Attenuate Obesity-Induced Intestinal Barrier Dysfunction by Induction of Antimicrobial Peptides

Impact of sodium butyrate on stroke-related intestinal injury in diabetic mice: Interference with Caspase-1/GSDMD pyroptosis pathway and preservation of intestinal barrier

Diabetic stroke-associated acute intestinal injury is characterized by high mortality, disability, and poor prognosis due to the lack of effective therapies. Our prior research demonstrated that administration of 300 mg/kg sodium butyrate (NaB) can improve neurological outcomes post-diabetic stroke. Nonetheless, whether the effect of NaB is related to intestinal regulation, along with its underlying mechanisms, remains uncertain. This study aims to investigate the effects and mechanistic pathways of NaB on diabetic stroke-associated acute intestinal injury. A middle cerebral artery occlusion/reperfusion model was established in mice with streptozotocin-induced diabetes. The results demonstrated that NaB alleviated colonic injury 24 h after reperfusion in diabetic stroke. Pyroptosis-related protein levels in colonic tissues were significantly elevated following diabetic stroke but were markedly reduced with NaB treatment. NaB also improved gut barrier integrity and reduced inflammation, promoting epithelial barrier self-repair. In the NaB combined with lipopolysaccharide group, lipopolysaccharide administration induced a significant inflammatory response in the colonic tissue. Conversely, treatment with NaB and VX-765 (an inhibitor for Caspase-1) led to a notable alleviation in intestinal inflammation. These findings suggest that NaB mitigates colonic injury and enhances barrier function following diabetic stroke, potentially through the Caspase-1/Gasdermin D pyroptosis pathway. This study may provide a novel strategy and direction for intestinal rehabilitation in diabetic stroke patients.

Nanoparticle-mediated sodium butyrate delivery for repairing hypoxic-ischemic brain injury in premature infants

Hypoxic-ischemic encephalopathy of prematurity (HIEP) is a leading cause of acute mortality and chronic neurological injury in premature infants. This study investigates the molecular mechanisms by which magnetic fluorescent nanoparticles loaded with sodium butyrate (MNs@SB) repair HIEP by modulating the Sp1 and TGF-β1 signaling pathways. Untargeted metabolomics analysis revealed significant suppression of the butyrate metabolism pathway in the intestinal tissues of HIEP mice. We synthesized and characterized MNs@SB nanoparticles, with zeta potential and DLS results indicating an average nanoparticle size of approximately 79.89 nm and a zeta potential of -36.87 mV. TEM images confirmed that the nanoparticles formed polymer-coated clusters. MNs@SB demonstrated excellent biocompatibility and stable magnetic targeting behavior. The nanoparticles were delivered to the brain via tail vein injection and magnetic targeting, with focused ultrasound facilitating their diffusion. The results showed that HIEP mice exhibited a significant increase in infarct size and extensive tissue loss, whereas MNs@SB treatment effectively reversed HIEP-induced brain damage, improving both short-term and long-term neurological deficits. Single-cell RNA sequencing and high-throughput transcriptome analysis revealed that MNs@SB promoted brain repair by upregulating neuronal Sp1, activating the TGF-β1 signaling pathway, and inhibiting neuronal apoptosis. In vivo experiments further confirmed that MNs@SB treatment restored SP1 mRNA and protein expression in the brain. Additionally, MNs@SB treatment significantly restored TGF-β1, p-SMAD2, and p-SMAD3 protein expression, indicating activation of the TGF-β1/SMAD2/3 signaling pathway. This study presents a novel nanomedicine therapeutic strategy with potential clinical applications.

Microbiota-induced inflammation mediates the impacts of a Western diet on hippocampal-dependent memory

Obesity is associated with impaired hippocampal-dependent memory, but the mechanisms driving this pathology are not fully understood. Western diets (WD) contribute to obesity, and previous reviews have described a role for WD in impaired hippocampal-dependent memory. However, there is need for a more detailed description of the pathways by which WD may impair memory. The short vs long-term effect of specific dietary components on brain structure and functions as well as the precise mechanism and molecular pathways involved are still not fully understood. This review focuses on the mechanisms and effects of gut microbiota-driven neuroinflammation. WD leads to changes and imbalance in bacterial taxa abundances that are deleterious to the host health (gut dysbiosis) and studies in rodent models show these changes are sufficient to impair hippocampal-dependent memory. Here, we discuss a variety of proposed mechanisms linking microbiota composition to hippocampal function, with a focus on neuroinflammation. Gut microbiota impacts gastrointestinal barrier function, leading to increased circulating proinflammatory bacterial products, increased blood-brain barrier permeability, and neuroinflammation.

Links between short-chain fatty acids and osteoarthritis from pathology to clinic via gut-joint axis

Short-chain fatty acids (SCFAs), the primary metabolites produced by the microbial fermentation of dietary fibers in the gut, have a key role in protecting gut health. Increasing evidence indicates SCFAs can exert effects on distant tissues and organs beyond the gut via blood circulation. Osteoarthritis (OA) is a chronic inflammatory joint disease that severely diminishes the physical function and quality of life. However, effective clinical treatments for OA remain elusive. Recent studies have shown that SCFAs can exert beneficial effects on damaged joints in OA. SCFAs can mitigate OA progression by preserving intestinal barrier function and maintaining the integrity of cartilage and subchondral bone, suggesting that they have substantial potential to be the adjunctive treatment strategy for OA. This review described the SCFAs in the human body and their cellular signaling mechanism, and summarized the multiple effects of SCFAs (especially butyrate, propionate, and acetate) on the prevention and treatment of OA by regulating the gut-joint axis, providing novel insights into their promising clinical applications.

Evaluation of Defensins as Markers of Gut Microbiota Disturbances in Children with Obesity and Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Until recently, it was believed that bacterial translocation occurs as a result of leaky gut syndrome or sepsis. To confirm or exclude the process of bacterial translocation, biomarkers can be used. One such biomarker is defensins, which indicate immune activity, as defensins are cationic peptides with antibacterial properties produced by intestinal epithelial cells. Also, fatty acid-binding proteins (I-FABP and L-FABP) can serve as useful serological markers for intestinal epithelial damage, indicating impaired intestinal permeability or organ damage, as high concentrations of them are found in tissues and low concentrations in blood serum. In the context of obesity, the integrity of the intestinal barrier, which can be disrupted by dietary fat, leads to increased intestinal permeability. Since bacterial translocation and microbiota contribute to obesity and Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) associated with metabolic dysfunction, intestinal barrier markers can be used to study the role of the gut-liver axis. The aim of this study was to gain insight into the pathogenesis of MASLD and examine the impact of bacterial translocation markers and intestinal and hepatic fatty acid-binding proteins (I-FABP and L-FABP) in children with MASLD. Method: We examined 60 children with MASLD and overweight/obesity (MASLD was diagnosed based on increased liver echogenicity in ultrasound and elevated ALT activity), aged 14.5 years (range 8.5 to 15.8); 33 children with overweight/obesity without MASLD, aged 13.0 years (range 11.4 to 15.8); and 16 healthy controls aged 11.0 years (range 7.0 to 16.2). Defensin, I-FABP, and L-FABP levels were measured using commercial kits: ELISA kits (Drg Medtek) were used to assess α-5 and α-6 defensin concentrations (HBD5, HBD6). I-FABP and L-FABP concentrations were measured using commercial ELISA kits (Hycult Biotech Inc., Wayne, PA, USA). ANOVA analysis was used to compare results across the three study groups. Results: A significant difference was found for the following tests among children with MASLD, obesity, and healthy controls: defensin 6 (14.4 ng/mL vs. 6.13 ng/mL vs. 17.2 ng/mL, respectively), L-FABP (9168 pg/mL vs. 7954 pg/mL vs. 7620 pg/mL, respectively), and I-FABP (272 pg/mL vs. 321 pg/mL vs. 330 pg/mL, respectively). No differences were found in defensin 5 levels (median 567.2 pg/mL vs. 485.7 pg/mL vs. 601.8 pg/mL). No differences were observed in cholesterol levels (HDL, LDL) or triglyceride concentrations, as well as apolipoprotein levels. Conclusions: Based on our study, it was concluded that inflammation and intestinal barrier damage lead to increased L-FABP levels, as it is released from enterocytes in response to oxidative stress or tissue damage. Defensin 6 may indirectly affect L-FABP through microbiota regulation and protection of the intestinal barrier. Defensin 6 also exerts antimicrobial activity and may accompany liver inflammation, with its increased concentration in comparison to obesity explained by the activation of defense mechanisms.

Polysaccharides in the medicine and food homology to combat obesity via gut-liver axis: A review of possible mechanisms

Polysaccharides, as macromolecular carbohydrates present in various medicine and food homology, have gained growing recognition for their potential in combating obesity through multiple mechanisms. Their natural origin and favorable safety profile have made polysaccharides from medicine and food homology (PMFH) an area of significant research interest, particularly in the context of developing effective, safe, and sustainable interventions for obesity management. This review summarized the classification and biological properties of PMFH and then elucidated the pathological characteristics of obesity. We primarily focused on the effects of PMFHs on obesity, with particular attention to the potential mechanisms mediated through the gut-liver axis. These mechanisms encompassed the improvement of fat metabolism imbalances, manager of appetite and energy balance, adjustment of intestinal microbial imbalances, and alleviation of oxidative stress and inflammation. The findings provided critical theoretical insights and data to support the development of anti-obesity dietary and pharmaceutical products. In brief, this review outlined future research directions regarding the potential mechanisms underlying the anti-obesity effects of PMFH, particularly those involving the gut-liver axis.

Sodium butyrate attenuates experimental neonatal necrotizing enterocolitis by suppressing TLR4-mediated NLRP3 inflammasome-dependent pyroptosis

Necrotizing enterocolitis (NEC) is a fatal intestinal disease in premature infants, and is characterized by intestinal inflammation and disruption of the intestinal barrier. The protective effects of sodium butyrate (NaB) against NEC have been documented, however, the underlying fundamental processes remain unknown. To address this deficit, we used the NEC neonatal rat model to confirm the intestinal protective effect of NaB. We then used network pharmacology and confirmed a role for NaB in the attenuation of NEC and this was associated with the NLRP3 inflammasome and the NF-κB signaling pathway. These results were verified by proteome analysis in vivo, and molecular docking analysis was used to explore the potential underlying mechanisms, revealing a suppressive function of NaB on NEC, which may be caused by its interaction with the TLR4-mediated NF-κB signaling pathway. An in vitro cell model (LPS-stimulated IEC-6 cells) was then established to confirm the docking results. Results using assays involving the NLRP3 (MCC950) and TLR4 (TAK-242) inhibitors suggested that NaB protected intestinal cells from inflammatory injuries during NEC by suppressing the TLR4/MyD88/NF-κB/NLRP3/cleaved caspase-1/GSDMD inflammasome pathway. These findings indicated that NaB can be used as a potential modulatory and therapeutic candidate for the treatment of NEC.

The Obesity-Epigenetics-Microbiome Axis: Strategies for Therapeutic Intervention

Obesity (OB) has become a serious health issue owing to its ever-increasing prevalence over the past few decades due to its contribution to severe metabolic and inflammatory disorders such as cardiovascular disease, type 2 diabetes, and cancer. The unbalanced energy metabolism in OB is associated with substantial epigenetic changes mediated by the gut microbiome (GM) structure and composition alterations. Remarkably, experimental evidence also indicates that OB-induced epigenetic modifications in adipocytes can lead to cellular "memory" alterations, predisposing individuals to weight regain after caloric restriction and subsequently inducing inflammatory pathways in the liver. Various environmental factors, especially diet, play key roles in the progression or prevention of OB and OB-related disorders by modulating the GM structure and composition and affecting epigenetic mechanisms. Here, we will first focus on the key role of epigenetic aberrations in the development of OB. Then, we discuss the association between abnormal alterations in the composition of the microbiome and OB and the interplays between the microbiome and the epigenome in the development of OB. Finally, we review promising strategies, including prebiotics, probiotics, a methyl-rich diet, polyphenols, and herbal foods for the prevention and/or treatment of OB via modulating the GM and their metabolites influencing the epigenome.

Macronutrients as Regulators of Intestinal Epithelial Permeability: Where Do We Stand?

The intestinal barrier function (IBF) is essential for intestinal homeostasis. Its alterations have been linked to intestinal and systemic disease. Regulation of intestinal permeability is key in the maintenance of the IBF, in which the intestinal epithelium and tight junctions, the mucus layer, sIgA, and antimicrobial peptides are important factors. This review addresses the concept of IBF, focusing on permeability, and summarizes state-of-the-art information on how starvation and macronutrients regulate it. Novel mechanisms regulate intestinal permeability, like its induction by the normal process of nutrient absorption, the contribution of starvation-induced autophagy, or the stimulation of sIgA production by high-protein diets in a T-cell-independent fashion. In addition, observations evidence that starvation and protein restriction increase intestinal permeability, compromising mucin, antimicrobial peptides, and/or intestinal sIgA production. Regarding specific macronutrients, substantial evidence indicates that casein (compared to other protein sources), specific protein-derived peptides and glutamine reinforce IBF. Dietary carbohydrates regulate intestinal permeability in a structure- and composition-dependent fashion; fructose, glucose, and sucrose increase it, while nondigestible oligosaccharides (NDOs) decrease it. Among NDOs, human milk oligosaccharides (HMOs) stand as a promising tool. NODs effects are mediated by intestinal microbiota modulation, production of short-chain fatty acids, and direct interactions with intestinal cells. Finally, evidence supports avoiding high-fat diets for their detrimental effects on IBF. Most studies have been carried out in vitro or in animal models. More information is needed from clinical studies to substantiate beneficial effects and the use of macronutrients in the treatment and prevention of IBF-related diseases.

Sub-chronic exposure of hexaconazole may induce metabolic and neuropathic diseases: The evidence from gut microbiota

The high-frequency detection and long persistence of hexaconazole (Hex) in agricultural products and environment poses potential risk to non-targeted organisms which should pay special attention to. Intestinal flora plays an important role in host health by prevention the occurrence of various diseases. Therefore, in this study, the disturbance of Hex on intestinal function and flora in rats had been studied at environmental related concentrations to evaluate the potential risk of Hex. Our results showed that Hex exposure induced serious oxidative stress and inflammation in intestinal tract. Meanwhile, it notably decreased the tight connectivity in colonic cell leading to the dysfunction of intestinal barrier. Moreover, 16sRNA gene sequencing showed that Hex exposure significantly disturbed the composition and structures of gut microbiota by decrease beneficial bacteria and increase pathogenic bacteria. Further, the metabolites and SCFAs that related to neuropathic and metabolic diseases in colonic contents were also significantly affected by Hex exposure. The pathways of membrane transport, replication and repair, lipid metabolism, and neurodegenerative diseases had been seriously interfered. The obtained results referred that Hex exposure may pose potential risk to metabolic system causing obesity, metabolic syndrome, and cardiovascular as well as nervous system inducing Parkinson's diseases, Alzheimer's diseases, and depression. Our study provided a new sight to study the mechanisms of Hex induced toxicity effects from the aspect of gut microbiota which could help for prevention the risk induced by Hex.

Potential applications and mechanisms of natural products in mucosal-related diseases

The mucosal barrier serves as a crucial defense against external pathogens and allergens, being widely distributed across the respiratory, gastrointestinal, urogenital tracts, and oral cavity. Its disruption can lead to various diseases, including inflammatory bowel disease, asthma, urinary tract infections, and oral inflammation. Current mainstream treatments for mucosa-associated diseases primarily involve glucocorticoids and immunosuppressants, but their long-term use may cause adverse effects. Therefore, the development of safer and more effective therapeutic strategies has become a focus of research. Natural products, with their multi-target and multi-system regulatory advantages, offer a promising avenue for the treatment of mucosal diseases. This review summarizes the potential applications of natural products in diseases of mucosal barrier dysfunction through mechanisms such as immune modulation, inflammation inhibition, tight junction protein restoration, and gut microbiota regulation, with the aim of providing insights for the exploration of novel therapeutic strategies.

Tannic Acid and Ethacridine Lactate Attenuate Markers of Stress-Induced Intestinal Barrier Dysfunctions in Murine Small Intestinal Organoids

(1) Background: Tannacomp® is a drug consisting of tannin albuminate, a complex of tannic acid (TA) and ethacridine lactate (Eta) used for treating acute and traveler's diarrhea. TA is thought to modulate gastrointestinal barrier function, but the underlying mechanisms and whether Eta has similar effects remains unclear. (2) Methods: to investigate the effects of TA and Eta on the intestinal barrier, stress responses were induced in murine intestinal organoids by lipopolysaccharide (LPS) exposure or withdrawal of growth factors from cell culture medium (GFRed). Further, organoids were exposed to either TA (0.01 mg/mL) or Eta (0.002 mg/mL) and markers of inflammatory response and gut barrier function were assessed. (3) Results: TA and Eta reduced several inflammatory markers such as interleukin 6, interleukin 1β, tumor necrosis factor α, and myeloid differentiation primary response 88 in stressed organoids. In addition, TA and Eta attenuated LPS- and GFRed-mediated gut barrier dysfunctions, with normalization of tight junction, adherent junction and mucin gene expression and reduction of Nod2- and matrix metalloproteinase 7-dependent activation of antimicrobial peptides. (4) Conclusions: our data show that TA and Eta modulate markers of inflammation and the intestinal barrier and suggest novel mechanisms of action of this drug that could broaden its treatment indications.

From Childhood Obesity to Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) and Hyperlipidemia Through Oxidative Stress During Childhood

BACKGROUND/OBJECTIVES

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is rapidly becoming the most prevalent form of chronic liver disease in both pediatric and adult populations. It encompasses a wide spectrum of liver abnormalities, ranging from simple fat accumulation to severe conditions such as inflammation, fibrosis, cirrhosis, and liver cancer. Major risk factors for MASLD include obesity, insulin resistance, type 2 diabetes, and hypertriglyceridemia.

METHODS

This narrative review employed a comprehensive search of recent literature to identify the latest studies on the relationship between MAFLD and obesity, the health consequences and the latest treatment options to prevent long-term damage to the liver and other organs. Additionally, the article presents perspectives on diagnostic biomarkers.

RESULTS

Childhood obesity is linked to a multitude of comorbid conditions and remains a primary risk factor for adult obesity. This abnormal fat accumulation is known to have long-term detrimental effects into adulthood. Scientific evidence unequivocally demonstrates the role of obesity-related conditions, such as insulin resistance, dyslipidemia, and hyperglycemia, in the development and progression of MASLD. Oxidative stress, stemming from mitochondrial dysfunction, is a leading factor in MASLD. This review discusses the interconnections between oxidative stress, obesity, dyslipidemia, and MASLD.

CONCLUSIONS

Atherogenic dyslipidemia, oxidative stress, inflammation, insulin resistance, endothelial dysfunction, and cytokines collectively contribute to the development of MASLD. Potential treatment targets for MASLD are focused on prevention and the use of drugs to address obesity and elevated blood lipid levels.

The butyrate derived from probiotic Clostridium butyricum exhibits an inhibitory effect on multiple myeloma through cell death induction

Multiple myeloma (MM) is a hematological malignancy characterized by a poor prognosis. While certain probiotics have been shown to produce antitumor molecules that inhibit solid tumor progression, it remains unclear whether probiotic-derived compounds can exert similar effects on hematological tumors, such as MM. In this study, we screened the cell-free culture supernatants (CFCS) of 24 probiotic strains for antitumor effects against multiple myeloma (MM) cells and identified that the CFCS from Clostridium butyricum (C. butyricum) demonstrated the most significant reduction in MM cell viability. Further fractionation of this CFCS through reverse-phase and gel filtration chromatography revealed a high enrichment of butyrate in the antitumor fraction, as confirmed by gas chromatography-mass spectrometry. Butyrate reduced MM cell viability in a concentration-dependent manner. Butyrate was significantly more cytotoxic to RPMI-8226 cells than peripheral blood mononuclear cells (PBMCs) isolated from two non-cancerous individuals. In the xenograft model of RPMI-8226 cells, butyrate showed significant inhibition of tumor formation. Cell cycle analysis showed that butyrate induced G1 phase arrest and increased sub-G1 phase, suggesting DNA fragmentation. Western blot analysis demonstrated that butyrate treatment led to cleaved poly ADP-ribose polymerase (PARP) accumulation. Additionally, flow cytometry showed an increase in annexin V positive MM cells, indicating apoptosis. Butyrate also exhibited synergistic antitumor activity when combined with bortezomib, a proteasome inhibitor. These findings suggest that probiotic-derived molecules, including butyrate, may enhance the therapeutic effect of hematological malignancy, such as MM.

Interest of inulin in obesity: comparison of the prebiotic effect of edible-food sources versus purified inulin from chicory root

PURPOSE

Inulin-type fructans (ITF) are fermentable dietary fibres (DF) that can confer beneficial metabolic health effects through changes in the gut microbiota. Many papers suggest that complex food rich in DF could be more relevant than purified DF in terms of health effect. We compared the prebiotic effect of natural source of inulin (scorzonera) versus native inulin extracted from chicory root in a model of obesity.

METHODS

Mice were fed during 6 weeks a low-fat (LF), high-fat (HF) or high-fat diet enriched with either purified inulin from chicory root (Inu) or lyophilized scorzonera (Sco), with the same amount of ITF intake (10%) versus a non-fermentable fibre (cellulose). Metabolic parameters were correlated with the gut microbiome composition (16S rRNA gene sequencing).

RESULTS

Both inulin sources reduced food intake without significantly modifying body weight gain or adiposity compared to HF. Purified inulin and lyophilized scorzonera differentially modulate the gut physiology and microbiota. Both inulin and scorzonera shifted global gut microbial composition from HF group, decreased members of Desulfovibrionaceae and boosted bifidobacteria level. Some effects were specific to Sco group, such as the increase of Akkermansia and the decrease of Bacteroides, that correlated to biological outcomes. Inu improved hepatic steatosis whereas scorzonera boosted intestinal immunity markers and antimicrobial peptides expression, and increased intestinal crypt depth.

CONCLUSION

Differences occur between natural edible versus isolated sources of ITF. Both sources of inulin shifted the gut microbiota, but differently affected intestinal and lipid homeostasis. This study highlights the importance of food matrix and origins of fructans for their use in the context of metabolic disorders.

Inulin Protects Caco-2 Cells Against Lipopolysaccharide-Induced Epithelial Barrier Dysfunction

Lipopolysaccharide (LPS), a component of the outer membrane of Gram-negative bacteria, triggers inflammatory responses in intestinal epithelial cells. This activation leads to the production of pro-inflammatory cytokines which disrupt cellular homeostasis. LPS also impairs the integrity of the intestinal epithelial barrier by downregulating tight junction proteins, resulting in increased intestinal permeability. This compromised barrier function can allow further translocation of luminal antigens, perpetuating inflammation and contributing to gut-related disorders such as inflammatory bowel disease (IBD) and metabolic endotoxemia. This study investigated the therapeutic effects of inulin, a prebiotic dietary fiber, in attenuating LPS-induced intestinal epithelial barrier dysfunction. Caco-2 cells were treated with 100 ng/mL of LPS for 12 h, resulting in increased gene expression of pro-inflammatory cytokines (IL-1β, TNF-α, and IL-18) and a significant downregulation of tight junction proteins claudin-1 and claudin-2, while occludin gene expression remained unaffected. Pretreatment with 2% inulin for 24 h before LPS exposure prevented the downregulation of claudin-1 and claudin-2 and significantly upregulated occludin gene expression. These molecular findings were supported by functional assays using transwell systems. LPS treatment increased paracellular permeability of the Caco-2 monolayer, indicating barrier dysfunction, while inulin pretreatment mitigated this effect. These results demonstrate that inulin can modulate tight junction protein expression and maintain gut barrier integrity under inflammatory conditions.

Oral tributyrin treatment affects short-chain fatty acid transport, mucosal health, and microbiome in a mouse model of inflammatory diarrhea

Butyrate may decrease intestinal inflammation and diarrhea. This study investigates the impact of oral application of sodium butyrate (NaB) and tributyrin (TB) on colonic butyrate concentration, SCFA transporter expression, colonic absorptive function, barrier properties, inflammation, and microbial composition in the colon of slc26a3-/- mice, a mouse model for inflammatory diarrhea. In vivo fluid absorption and bicarbonate secretory rates were evaluated in the cecum and mid-colon of slc26a3+/+ and slc26a3-/- mice before and during luminal perfusion of NaB-containing saline and were significantly stimulated in both slc26a3+/+ and slc26a3-/- colon by NaB. Age-matched slc26a3+/+ and slc26a3-/- mice were either fed chow containing 5% NaB or gavaged twice daily with TB for 21 d. Food and water intake, weight, and stool water content were assessed daily. Stool and tissues were collected for further analysis of SCFA production, barrier integrity, mucosal inflammation, and microbiome analysis by 16S rRNA gene sequencing. 5% NaB diet did not exert a significant impact on SCFA levels, mucus barrier, or inflammatory markers, but significantly increased oral water intake. TB gavage treatment increased the expression of SCFA transporters Mct1 and Smct1, mucus content and microbial diversity, and decreased the neutrophil marker Lipocalin 2, Phospholipase A2, and the antimicrobial peptide Reg3b in the slc26a3-/- cecum. However, TB treatment also resulted in an increase in inflammatory markers such as TNFα, Il-1β and CD3e in the wildtype mucosa. While there are some benefits with TB ingestion for barrier properties and microbial composition in the diseased cecum, potentially detrimental effects were noted in the healthy colon.

Epigenomic mechanisms of dietary prescriptions for obesity therapy

Dietary modification is a cornerstone and a primary goal for weight loss, whose effects may be related to epigenetic phenomena. In this literature review, a comprehensive search without time restriction was performed in PubMed/Medline, Cochrane, SciELO, and Scopus databases to identify epigenetic signatures related to obesity outcomes upon dietary advice. In this context, experimental studies and clinical trials have identified certain DNA methylation marks, miRNA expression profiles and histone modifications putatively associated with adiposity outcomes after different nutritional interventions. These include traditional dietary patterns, diets with different macronutrient compositions, and supplementation with fatty acids, amino acids and derivatives, methyl donors, vitamins and minerals, probiotics and prebiotics, and bioactive food compounds. Some of these epigenetic signatures have been mapped to genes involved in food intake control, adipogenesis, lipolysis, fatty acid oxidation, body fat deposition, and gut microbiota modulation. However, additional studies are still required to address dosage and follow-up variability, validation of epigenetic marks, genome-wide approaches, and appropriate statistical settings. Although more investigation is required, these insights may contribute to the characterization of epigenetic biomarkers of body weight regulation toward the prescription of tailored dietary strategies targeting the epigenome for a more precise obesity management and control.

Butyrate improves testicular spermatogenic dysfunction induced by a high-fat diet

Background

Obesity is closely associated with low male fertility and decreased sperm quality. Obesity is accompanied by an ecological imbalance in the gut microbiota, so it is of great significance to intervene in male infertility caused by obesity from the perspective of gut microbiota metabolites. This study aimed to evaluate the efficacy of butyrate in ameliorating obesity-induced spermatogenic dysfunction and to explore the potential molecular mechanisms.

Methods

This study explored the role of butyrate in recovering the dysfunctions of spermatogenesis caused by obesity by inducing an obese model of male mice with a high-fat diet (HFD). The effects of HFD and butyrate on testicular function were explored based on metabolomics.

Results

The results of the study showed that HFD caused a decrease in sperm count, a decrease in sperm motility, and an increase in sperm malformation rate in mice. After adding butyrate to the HFD, the various sperm indicators of mice were significantly improved. Through the analysis of metabolomics data from mouse testes, this study found that an HFD significantly altered the metabolic status of mice testes, involving multiple metabolic pathways. However, after adding butyrate, some metabolic characteristics tended to be similar to those of normal diet mice, and the steroid biosynthesis and primary bile acid biosynthesis pathways were significantly improved.

Conclusions

This study clarified the effect of butyrate on improving sperm quality, providing experimental evidence for the treatment of obesity-induced abnormal spermatogenesis with butyrate.

Gut microbiota differences, metabolite changes, and disease intervention during metabolic - dysfunction - related fatty liver progression

In the current era, metabolic dysfunction-associated steatotic liver disease (MASLD) has gradually developed into a major type of chronic liver disease that is widespread globally. Numerous studies have shown that the gut microbiota plays a crucial and indispensable role in the progression of MASLD. Currently, the gut microbiota has become one of the important entry points for the research of this disease. Therefore, the aim of this review is to elaborate on the further associations between the gut microbiota and MASLD, including the changes and differences in the microbiota between the healthy liver and the diseased liver. Meanwhile, considering that metabolic dysfunction-associated fatty liver and metabolic dysfunction-associated steatohepatitis are abnormal pathological states in the development of the disease and that the liver exhibits different degrees of fibrosis (such as mild fibrosis and severe fibrosis) during the disease progression, we also conduct a comparison of the microbiota in these states and use them as markers of disease progression. It reveals the changes in the production and action mechanisms of short-chain fatty acids and bile acids brought about by changes in the gut microbiota, and the impact of lipopolysaccharide from Gram-negative bacteria on the disease. In addition, the regulation of the gut microbiota in disease and the production and inhibition of related disease factors by the use of probiotics (including new-generation probiotics) will be explored, which will help to monitor the disease progression of patients with different gut microbiota compositions in the future and carry out personalized targeted therapies for the gut microbiota. This will achieve important progress in preventing and combating this disease.

Association of type 2 diabetes, hypertension, and hyperlipidemia with immune-related adverse events in patients undergoing immune checkpoint inhibitors therapy

Aims

Immune-related adverse events (irAEs) pose a significant challenge to the clinical use of immune checkpoint inhibitors (ICIs) in cancer immunotherapy. This study aims to determine whether comorbid conditions such as type 2 diabetes (T2DM), hypertension, and hyperlipidemia affect the risk of irAEs in cancer patients receiving ICIs treatments.

Materials and methods

We conducted a retrospective analysis of clinical data from 3,489 cancer patients treated with ICIs (anti-PD-1, anti-PD-L1, and anti-CTLA-4) at West China Hospital of Sichuan University from 2017 to 2022. Logistic regression models were used to evaluate the associations between T2DM, hypertension, and hyperlipidemia with irAEs. Subgroup analyses assessed irAEs in patients with and without these comorbidities across different cancer types. Additionally, we explored the associations between comorbidities and irAEs affecting different organs.

Results

The results showed that comorbid T2DM, hypertension, and hyperlipidemia significantly increased the risk of irAEs in all cancer types (T2DM: OR=1.40, 95% CI: 1.12-1.74, p=0.003; hypertension: OR=1.21, 95% CI: 1.00-1.45, p=0.049; hyperlipidemia: OR=1.62, 95% CI: 1.02-2.53, p=0.038). T2DM primarily increased the risk of irAEs in lung cancer patients (OR = 1.50, 95% CI: 1.12-2.01, FDR-adjusted p = 0.036), and all three comorbidities significantly elevated the risk of cardiac irAEs.

Conclusions

Our study is the first to confirm an association between T2DM, hypertension, and hyperlipidemia and the occurrence of irAEs in cancer patients receiving ICIs therapy. This finding highlights the critical need for clinicians to perform comprehensive evaluations of patients' comorbidities prior to treatment.

Gut microbiota dysbiosis involved in decabromodiphenyl ether-induced bone homeostasis disorder through inflammaging

BDE-209 has a causal relationship with adverse health outcomes. However, research on its effect on bone homeostasis is relatively lacking. This study examined the relationship between BDE-209 exposure and bone health, as well as the underlying mechanisms, using both in vitro and in vivo models. In animal studies, female SD rats were administered BDE-209 for 60 days. Bone mineral density, bone microstructure, gut microbiota, and inflammaging markers were measured. Furtherly, THP-1 cell-derived macrophages were treated with a culture medium containing population-relevant dose of BDE-209 or sodium butyrate. The expression of M1 macrophage markers, osteoclast markers, and inflammatory cytokines was measured. Then macrophages were induced by osteoclast conditioned medium to evaluate the effect of BDE-209 on their differentiation into osteoclasts. Results showed reduced humeral bone density, enhanced osteoclast activity, upregulation of IL-1β, TNF-α, IL-6, and activation of PGC-1α/NAD+/cGAS-STING in the exposed group. 16s sequencing revealed that BDE-209 disrupts the abundance of the gut microbiota, notably a reduction in Lachnospiraceae. In vitro, BDE-209 can stimulate macrophages to differentiate more osteoclasts and activate the cGAS-STING pathway, while sodium butyrate can inhibit these effects. This study reveals that gut microbiota dysbiosis is involved in BDE-209-induced bone homeostasis disorder through inflammatory aging and sodium butyrate can mitigate this effect. Overall, this study provides research data for the precaution and treatment of osteoporosis associated with BDE-209 exposure.

Gut microbiota-derived short chain fatty acids act as mediators of the gut-liver-brain axis

The gut microbiota plays a crucial role in the communication between the gut, liver, and brain through the production of short chain fatty acids (SCFAs). SCFAs serve as key mediators in the Gut-Liver-Brain Axis, influencing various physiological processes and contributing to overall health. SCFAs are produced by bacterial fermentation of dietary fiber in the gut, and they exert systemic effects by signaling through various pathways. In the Gut-Liver axis, SCFAs regulate liver metabolism through peroxisome proliferator-activated receptor-γ (PPAR-γ), AMP-activated protein kinase (AMPK) and other pathways, promotes fat oxidation, modulate inflammation through mTOR pathway, and impact metabolic health. In the Gut-Brain axis, SCFAs influence brain function, behavior, and may have implications for neurological disorders, in which G-protein coupled receptors (GPCRs) play an essential role, along with other pathways such as hypothalamic-pituitary-adrenal (HPA) pathway. Understanding the mechanisms by which SCFAs mediate communication between the gut, liver, and brain is crucial for elucidating the complex interplay of the Gut-Liver-Brain Axis. This review aims to provide insight into the role of gut microbiota-derived SCFAs as mediators of the Gut-Liver-Brain Axis and their potential therapeutic implications. Further research in this area will be instrumental in developing novel strategies to target the Gut-Liver-Brain Axis for the prevention and treatment of various health conditions.

The essential role of prebiotics in restoring gut health in long COVID

The gut microbiota (GM) plays an essential role in human health, influencing not only digestive processes but also the immune system´s functionality. The COVID-19 pandemic has highlighted the complex interaction between viral infections and the GM. Emerging evidence has demonstrated that SARS-CoV-2 can disrupt microbial homeostasis, leading to dysbiosis and compromised immune responses. The severity of COVID-19 has been associated with a reduction in the abundance of several beneficial bacteria in the gut. It has been proposed that consuming probiotics may help to re-colonize the GM. Although probiotics are important, prebiotics are essential for their metabolism, growth, and re-colonization capabilities. This chapter delves into the critical role of prebiotics in restoring GM after COVID-19 disease. The mechanisms by which prebiotics enhance the metabolism of beneficial bacteria will be described, and how prebiotics mediate the re-colonization of the gut with beneficial bacteria, thereby restoring microbial diversity and promoting the resilience of the gut-associated immune system. The benefits of consuming prebiotics from natural sources are superior to those from chemically purified commercial products.

Sodium butyrate prevents lipopolysaccharide induced inflammation and restores the expression of tight junction protein in human epithelial Caco-2 cells

The gastrointestinal (GI) tract is susceptible to damage under high altitude hypoxic conditions, leading to gastrointestinal discomfort and intestinal barrier injury. Sodium butyrate, a short-chain fatty acid present as a metabolite in the gut, has emerged as a promising therapeutic agent due to its ability to act as an immunomodulatory agent and restore intestinal barrier integrity. This study aimed to explore the mechanism by which sodium butyrate exhibits anti inflammatory effect on intestinal epithelial cells. In vitro, Caco-2 epithelial cells and RAW 264.7 macrophages were used to investigate the protective role of sodium butyrate on Lipopolysaccharide (LPS) induced inflammation. Cell viability assays demonstrated that 1 mM (110.86 μg/mL) of sodium butyrate did not exhibit cytotoxicity on cells in vitro. Treatment with sodium butyrate suppressed reactive oxygen species levels and TNF-α production in LPS-stimulated macrophages, indicating its efficacy in mitigating inflammatory responses. Western blot analysis revealed that sodium butyrate attenuated the expression of iNOS in RAW 264.7 macrophage cells. Moreover, sodium butyrate also reversed the LPS induced over expression of HIF-1α, NLRP3, IL-1β as well as NF-kB in Caco-2 epithelial cells and also had a suppressive effect on IL-8 secretion after LPS stimulation. Immunocytochemistry demonstrated that sodium butyrate enhanced tight junction protein occludin expression in Caco-2 cells while also restoring the decreased permeability of the Caco-2 monolayer due to LPS. These results indicate that sodium butyrate may influence immune responses by suppressing inflammatory mediators and improving the integrity of the epithelial barrier. Understanding the intricate interactions between gut metabolites and host immune responses may help in the development of innovative therapeutic strategies to alleviate intestinal inflammation in high altitude environments.

Immunomodulatory Effects of Selected Non-Nutritive Bioactive Compounds and Their Role in Optimal Nutrition

The contemporary approach to nutrition increasingly considers the role of non-nutritive bioactive compounds in modulating the immune system and maintaining health. This article provides up-to-date insight into the immunomodulatory effects of selected bioactive compounds, including micro- and macronutrients, vitamins, as well as other health-promoting substances, such as omega-3 fatty acids, probiotics, prebiotics, postbiotics (including butyric acid and sodium butyrate), coenzyme Q10, lipoic acid, and plant-derived components such as phenolic acids, flavonoids, coumarins, alkaloids, polyacetylenes, saponins, carotenoids, and terpenoids. Micro- and macronutrients, such as zinc, selenium, magnesium, and iron, play a pivotal role in regulating the immune response and protecting against oxidative stress. Vitamins, especially vitamins C, D, E, and B, are vital for the optimal functioning of the immune system as they facilitate the production of cytokines, the differentiation of immunological cells, and the neutralization of free radicals, among other functions. Omega-3 fatty acids exhibit strong anti-inflammatory effects and enhance immune cell function. Probiotics, prebiotics, and postbiotics modulate the intestinal microbiota, thereby promoting the integrity of the intestinal barrier and communication between the microbiota and the immune system. Coenzyme Q10, renowned for its antioxidant attributes, participates in the protection of cells from oxidative stress and promotes energy processes essential for immune function. Sodium butyrate and lipoic acid exhibit anti-inflammatory effects and facilitate the regeneration of the intestinal epithelium, which is crucial for the maintenance of immune homeostasis. This article emphasizes the necessity of an integrative approach to optimal nutrition that considers not only nutritional but also non-nutritional bioactive compounds to provide adequate support for immune function. Without them, the immune system will never function properly, because it has been adapted to this in the course of evolution. The data presented in this article may serve as a foundation for further research into the potential applications of bioactive components in the prevention and treatment of diseases associated with immune dysfunction.

Cecropin AD ameliorates pneumonia and intestinal injury in mice with mycoplasma pneumoniae by mediating gut microbiota

Animals infected with mycoplasma pneumoniae not only develop respiratory diseases, but also cause digestive diseases through the lung-gut axis mediated by the intestinal flora, and vice versa. Antimicrobial peptides are characterized by their bactericidal, anti-inflammatory, and intestinal flora-regulating properties. However, the effect of cecropin AD (CAD) against mycoplasma pneumonia remains unclear. To investigate the anti-inflammatory effect of CAD on mycoplasma pneumonia and the associated mechanism, mice were infected with Mycoplasma capricolum subsp. Capripneumoniae(Mccp) to elicit lung inflammation, followed by oral administration of CAD via gavage. The findings showed that mice receiving twice injections of 2.08 × 108 copies of Mccp suffered significant pathological damage to their lungs and colons. Additionally, there was a notable upsurge in inflammatory factors within the affected tissues. 16 S rDNA sequencing revealed alterations in the colonic microbiota, including a decrease in the abundance of beneficial bacteria such as Corynebacterium_glutamicum and Candidatus_Saccharimonas, and an increase in the abundance of potential pathogens like Lachnospiraceae_NK4A136_group and Escherichia-Shigella. As a result, there were abnormal rises in lipopolysaccharide (LPS) levels in both colonic content and blood. Moreover, CAD treatment reversed the microbial dysbiosis and decreased the LPS levels induced by Mccp, thereby suppressing the activation of the TLR-4/NF-κB pathway and the Fas/FasL-caspase-8/-3 pathway. Consequently, this significantly mitigated the morphological and functional damage to the lungs and colons caused by Mccp. The findings offer novel insights and approaches for the clinical management of Mccp infections.

The association between the dietary index for gut microbiota and metabolic dysfunction-associated fatty liver disease: a cross-sectional study

BACKGROUND

The relationship between the gut microbiome and metabolic dysfunction-associated fatty liver disease (MAFLD) has garnered increasing attention. However, the association between the dietary index for gut microbiota (DI-GM), a measure of microbiome diversity, and MAFLD has yet to be fully explored.

METHODS

Data from the 2017-2020 National Health and Nutrition Examination Survey (NHANES) were analyzed, including 7243 participants. The association between DI-GM and MAFLD was investigated using weighted logistic regression, restricted cubic spline (RCS), and subgroup analyses.

RESULTS

A notable inverse association was identified between DI-GM and the prevalence of MAFLD, with each 1-point increase in DI-GM corresponding to a 6.1% reduction in MAFLD prevalence (OR = 0.939, 95% CI: 0.901-0.980). Individuals with a DI-GM score of 6 or higher had an adjusted OR of 0.794 (95% CI: 0.665-0.947) compared to those with a DI-GM score of 0-3. RCS analysis further revealed a linear relationship between DI-GM and MAFLD risk. Additionally, subgroup analyses suggested that race may modify the association between DI-GM and MAFLD (P for interaction < 0.05).

CONCLUSIONS

DI-GM is inversely associated with MAFLD prevalence, and race appears to be a significant modifier of this relationship.

The effect of gut microbiome-targeted therapies in nonalcoholic fatty liver disease: a systematic review and network meta-analysis

Background

The incidence of NAFLD is increasing. Preclinical evidences indicate that modulation of the gut microbiome could be a promising target in nonalcoholic fatty liver disease.

Method

A systematic review and network meta-analysis was conducted to compare the effect of probiotics, synbiotics, prebiotics, fecal microbiota transplant, and antibiotics on the liver-enzyme, metabolic effects and liver-specific in patients with NAFLD. The randomized controlled trails (RCTs), limited to English language were searched from database such as Pubmed, Embase, Web of science and Cochrane Library from inception to November 2024. Review Manager 5.3 was used to to draw a Cochrane bias risk. Inconsistency test and publication-bias were assessed by Stata 14.0. Random effect model was used to assemble direct and indirect evidences. The effects of the intervention were presented as mean differences with 95% confidence interval.

Results

A total of 1921 patients from 37 RCTs were eventually included in our study. 23 RCTs evaluated probiotics, 10 RCTs evaluated synbiotics, 4 RCTs evaluated prebiotics, 3 RCTs evaluated FMT and one RCT evaluated antibiotics. Probiotics and synbiotics were associated with a significantly reduction in alanine aminotransferase [ALT, (MD: -5.09; 95%CI: -9.79, -0.39), (MD: -7.38, 95CI%: -11.94, -2.82)] and liver stiffness measurement by elastograph [LSM, (MD: -0.37;95%CI: -0.49, -0.25), (MD: -1.00;95%CI: -1.59, -0.41)]. In addition to, synbiotics was superior to probiotics in reducing LSM. Synbiotics was associated with a significant reduction of Controlled Attenuation Parameter [CAP, (MD: -39.34; 95%CI: -74.73, -3.95)]. Both probiotics and synbiotics were associated with a significant reduction of aspartate transaminase [AST, (MD: -7.81; 95%CI: -15.49, -0.12), (MD: -13.32; 95%CI: -23, -3.64)]. Probiotics and Allogenic FMT was associated with a significant reduction of Homeostatic Model Assessment for Insulin Resistance [HOMA-IR, (MD: -0.7, 95%CI: -1.26, -0.15), (MD: -1.8, 95%CI: -3.53, - 0.07)]. Probiotics was associated with a significant reduction of body mass index [BMI, MD: -1.84, 95%CI: -3.35, -0.33].

Conclusion

The supplement of synbiotics and probiotics maybe a promising way to improve liver-enzyme, LSM, and steatosis in patients with NAFLD. More randomized controlled trials are needed to determine the efficacy of FMT and antibiotics on NAFLD. And the incidence of adverse events of MTTs should be further explored.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, CRD42023450093.

Butyrate: A potential mediator of obesity and microbiome via different mechanisms of actions

Butyrate, a short-chain fatty acid, is a crucial product of gut microbial fermentation with significant implications for various metabolic and physiological processes. Dietary sources of butyrate are limited, primarily derived from the fermentation of dietary fibers by butyrate-producing gut bacteria. Butyrate exerts its effects primarily as a histone deacetylase (HDAC) inhibitor and through signaling pathways involving G protein-coupled receptors (GPCRs). Its diverse benefits include promoting gut health, enhancing energy metabolism, and potentially alleviating complications associated with obesity. However, the exact role of butyrate in obesity is still under investigation, with a limited number of human trials necessitating further research to determine its efficacy and safety profile. Moreover, butyrate impact on the gut-brain axis and its modulation of microbiome effect on behavior highlight its broader importance in regulating host physiology. A thorough understanding of the metabolic pathways and mechanisms of butyrate is essential for developing targeted interventions for metabolic disorders. Continued research is crucial to fully realize its therapeutic potential and optimize its clinical applications in human health. In summary, this review illuminates the multifaceted role of butyrate as a potential mediator of obesity and related metabolic changes.

Sishen Pill & Tongxieyaofang ameliorated ulcerative colitis through the activation of HIF-1α acetylation by gut microbiota-derived propionate and butyrate

BACKGROUND

Ulcerative colitis (UC) is a chronic inflammatory bowel disease closely related to gut microbiota dysbiosis and intestinal homeostasis imbalance. Sishen Pill&Tongxieyaofang (SSP-TXYF) has a long history of application in traditional Chinese medicine and is widely used in UC clinics. However, its mechanism of action is still unclear.

PURPOSE

This study aimed to explore the potential regulatory role of SSP-TXYF in protecting against UC through metabolites produced by the intestinal microbiota, and elucidate its underlying molecular mechanism.

STUDY DESIGN AND METHODS

16S rRNA and UPLC-QE-Orbitrap-MS were used to assess the microbiota and short-chain fatty acids (SCFAs). A rat model of 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced gut microbiota dysbiosis was used to study the effects of SSP-TXYF on UC in vivo. Intestinal epithelial cells-6 (IEC-6) were treated with lipopolysaccharide (LPS). The intestinal mucosal barrier (IMB) functions were investigated by alcian blue staining and western blot analysis. The mechanism of SSP-TXYF influenced the HIF-1α acetylation pathway was examined by real-time fluorescence quantitative PCR (qPCR), Western blotting, and Co-immunoprecipitation.

RESULTS

Using 16S rRNA gene-based microbiota analysis, we found that SSP-TXYF ameliorated TNBS-induced gut microbiota dysbiosis. We found that SSP-TXYF significantly inhibited the decreased abundance of Firmicutes in UC rats, in addition, the abundance of Actinobacteria was also improved. The mechanism of SSP-TXYF-treated TNBS-induced UC resulted from improved IMB functions via the activation of hypoxia-inducible factor-1 (HIF-1α) acetylation. Notably, SSP-TXYF Enriched microbiota-derived metabolites propionate and butyrate, which could activate HIF-1α acetylation in IEC. Furthermore, exogenous treatment of propionate and butyrate reproduced similar protective effects as SSP-TXYF to UC through improving HIF-1α-dependent IMB functions.

CONCLUSIONS

Overall, our findings suggest that the gut microbiota-propionate/butyrate-HIF-1α-IMB axis plays an important role in SSP-TXYF-maintaining intestinal homeostasis, which may represent a novel approach for UC prevention via the intervention of any link in this axis.

Regulation of endotoxemia through the gut microbiota: The role of the Mediterranean diet and its components

Endotoxemia is closely related to many diseases. As the largest endotoxin reservoir in the human body, the gut microbiota should be a key target for alleviating endotoxemia. The intestinal microbiota is believed to cause endotoxemia directly or indirectly by modifying the intestinal barrier function through dysbiosis, changing intestinal mucosal permeability and bacterial translocation. Diet is known to be the main environmental factor affecting the intestinal microbiota, and different diets and food components have a large impact on the gut microbiota. The Mediterranean diet, which received much attention in recent years, is believed to be able to regulate the gut microbiota, thereby maintaining the function of the intestinal barrier and alleviating endotoxemia. In this review, we focus on the relationship between the gut microbiota and endotoxemia, and how the Mediterranean dietary (MD) pattern can interfere with endotoxemia through the gut microbiota.

Targeting gut microbiota as a therapeutic target in T2DM: A review of multi-target interactions of probiotics, prebiotics, postbiotics, and synbiotics with the intestinal barrier

The global epidemic of type 2 diabetes mellitus (T2DM) imposes a substantial burden on public health and healthcare expenditures, thereby driving the pursuit of cost-effective preventive and therapeutic strategies. Emerging evidence suggests a potential association between dysbiosis of gut microbiota and its metabolites with T2DM, indicating that targeted interventions aimed at modulating gut microbiota may represent a promising therapeutic approach for the management of T2DM. In this review, we concentrated on the multifaceted interactions between the gut microbiota and the intestinal barrier in the context of T2DM. We systematically summarized that the imbalance of beneficial gut microbiota and its metabolites may constitute a viable therapeutic approach for the management of T2DM. Meanwhile, the mechanisms by which gut microbiota interventions, such as probiotics, prebiotics, postbiotics, and synbiotics, synergistically improve insulin resistance in T2DM are summarized. These mechanisms include the restoration of gut microbiota structure, upregulation of intestinal epithelial cell proliferation and differentiation, enhancement of tight junction protein expression, promotion of mucin secretion by goblet cells, and the immunosuppressive functions of regulatory T cells (Treg) and M2 macrophages. Collectively, these actions contribute to the amelioration of the body's metabolic inflammatory status. Our objective is to furnish evidence that supports the clinical application of probiotics, prebiotics, and postbiotics in the management of T2DM.

Phage cocktail alleviated type 2 diabetes by reshaping gut microbiota and decreasing proinflammatory cytokines

Type 2 diabetes (T2D), a global health concern, is closely associated with the gut microbiota. Restoration of a balanced microbiota and intestinal homeostasis benefit therapy of T2D. Some special phages may selectively alter the gut microbiota without causing dysbiosis, such as MS2 and P22. However, scarcely systematic analysis of cascading effects triggered by MS2 and P22 phages on the microbiota, as well as interactions between specific gut bacteria and systemic metabolism, seriously inhibit the development of positive interventions of phages. Based on multi-omic analysis, we analyzed the intrinsic correlations among specific microbiota, their bioactive metabolites, and key indicators of T2D. We found that gavage of the MS2-P22 phage cocktail could significantly alter the gut microbiome to attenuate dysbiosis of diabetic C57BL/6 mice caused by high-fat diets (HFDs) and streptozotocin (STZ), by affecting microbial compositions as well as their metabolic pathways and metabolites, especially increasing amounts of short-chain fatty acid-producing (SCFA-producing) bacteria (e.g., Blautia and Romboutsia) and short-chain fatty acids (SCFAs). Correspondingly, a noteworthy reduction in the number of several opportunistic pathogens occurred, e.g., Candidatus Saccharimonas, Aerococcus, Oscillibacter, Desulfovibrio, and Clostridium sensu stricto 1. Synchronously, the levels of proinflammatory cytokines and lipopolysaccharide (LPS) were reduced to recover gut barrier function in T2D mice. These findings might benefit the development of a new dietary intervention for T2D based on phage cocktails. KEY POINTS: • Intestinal barrier integrity of T2D mice is improved by a phage cocktail • Negative relationship between Muribaculaceae and Corynebacterium reshaped gut microbiota • Acetate, propionate, and butyrate decreased the level of proinflammatory factors.

Lactiplantibacillus plantarum L47 and inulin affect colon and liver inflammation in piglets challenged by enterotoxigenic Escherichia coli through regulating gut microbiota

Introduction

Infection by pathogenic bacteria during weaning is a common cause of diarrhea and intestinal inflammation in piglets. Supplementing the diet with synbiotics is beneficial for animal health. The strain of Lactiplantibacillus plantarum L47 (L47) isolated in our lab exhibited good probiotic properties when combined with inulin. Here, the effectiveness of combining L47 and inulin (CLN) in protecting against enterotoxigenic Escherichia coli (ETEC) induced colon and liver inflammation in weaned piglets was evaluated.

Methods

Twenty-eight piglets aged 21 days were randomly assigned into 4 groups: CON (control), LI47 (oral CLN culture fluid, 1010 CFU/d of L47 and 1 g/d of inulin), ECON (oral ETEC culture fluid, 1010 CFU/d), and ELI47 (oral CLN and ETEC culture fluid). After 24 days, the colon and liver samples were collected for further analysis.

Results and discussion

CLN alleviated colon damage caused by ETEC challenge, as evidenced by an increase of colonic crypt depth, mRNA expression of tight junction Claudin-1 and Occludin, GPX activity, the concentration of IL-10 and sIgA (p < 0.05). Moreover, there was a decrease in MDA activity, the load of E. coli, the concentration of LPS, gene expression of TLR4, and the concentration of TNF-α and IL-6 (p < 0.05) in colonic mucosa. Additionally, CLN counteracted liver damage caused by ETEC challenge by modulating pathways associated with immunity and disease occurrence (p < 0.05).

Conclusion

Supplementing with CLN alleviated colon inflammation induced by ETEC challenge by decreasing the E. coli/LPS/TLR4 pathway and regulating hepatic immune response and disease-related pathways, suggesting that CLN could protect intestinal and liver health in animals.

Inulin alleviates inflammatory response and gut barrier dysfunction via modulating microbiota in lipopolysaccharide-challenged broilers

This study was conducted to explore the protective effects of inulin against lipopolysaccharide (LPS)-induced inflammatory response and intestinal barrier dysfunction in broilers. 108 broilers were allocated to 3 treatments: 1) non-challenged broilers (Control, CON); 2) LPS-challenged broilers (LPS); 3) LPS-challenged broilers fed the basal diet supplemented with 15 g/kg of inulin (Inulin + LPS). At 21 d of age, the LPS-challenged groups received an intraperitoneal injection of LPS, and the CON group received an equal volume of saline. After 4 h of LPS exposure, samples of blood, intestinal mucosa and cecal digesta were collected. The results showed that LPS challenge induced systemic inflammation and damaged intestinal barrier function, whereas inulin attenuated LPS-induced production of pro-inflammatory cytokines by inhibiting the activation of TLR4 and NF-κB p65, and enhanced intestinal barrier function. In addition, LPS stimulation caused cecal microbial dysbiosis as shown by increased abundance of pathogenic bacteria including Ruminococcus_torques_group, Escherichia-Shigella and Subdoligranulum, while supplementation of inulin increased abundance of beneficial bacteria Faecalibacterium and Anaeroplasma, and metabolite production including propionate and butyrate concentrations. In conclusion, dietary supplementation of inulin could partially alleviate LPS-induced inflammation and intestinal barrier injury by modulating intestinal microbiota, thereby minimizing growth retardation of broilers. Our results provide a basis for the rational utilization of inulin in alleviating immune stress in broiler production.

Dietary Tributyrin Improves Growth Performance, Meat Quality, Muscle Oxidative Status, and Gut Microbiota in Taihe Silky Fowls under Cyclic Heat Stress

Heat stress adversely affects poultry production and meat quality, leading to economic losses. This study aimed to investigate the effects of adding tributyrin on growth performance, meat quality, muscle oxidative status, and gut microbiota of Taihe silky fowls under cyclic heat stress (CHS) conditions. In this study, 120-day-old Taihe silky fowls (male) were randomly divided into six dietary treatments. These treatments included a normal control treatment (NC, fed a basal diet), a heat stress control treatment (HS, fed a basal diet), and HS control treatments supplemented with 0.04%, 0.08%, 0.16%, and 0.32% tributyrin, respectively. The NC treatment group was kept at 24 ± 1 °C, while the HS treatment birds were exposed to 34 ± 1 °C for 8 h/d for 4 weeks. Results showed that CHS decreased growth performance and compromised the meat quality of broilers (p < 0.05). However, tributyrin supplementation improved ADG and FCR in broilers exposed to CHS (p < 0.05). Additionally, tributyrin supplementation resulted in increased shear force value and GSH-Px activity, as well as a decrease in drip loss, ether extract content, and MDA content of the breast muscle in broilers under CHS (p < 0.05). Furthermore, tributyrin supplementation up-regulated the mRNA expressions of Nrf2, NQO1, HO-1, SOD, and GSH-Px of the breast muscle in broilers exposed to CHS (p < 0.05). Based on these positive effects, the study delved deeper to investigate the impact of 0.16% tributyrin supplementation (HS + 0.16%T) on the cecum microbiota. The HS + 0.16%T treatment showed an increase in the relative abundance of Rikenellaceae_RC9_gut_group (p < 0.05) and a trend towards an increase in Lactobacillus (p = 0.096) compared to the HS treatment. The results indicate that supplementation successfully improved the growth performance and meat quality of Taihe silky fowls. Furthermore, tributyrin supplementation, particularly at levels of 0.16%, improved meat quality by enhancing muscle antioxidant capacity, which is believed to be associated with activation of the Nrf2 signaling pathway.

Inulin alleviates atherosclerosis through improving lipid metabolism, inflammation, and gut microbiota in ApoE-knockout mice: the short-chain is more efficacious

Introduction

Atherosclerosis (AS) is considered the underlying cause of many diseases, particularly cardiovascular and cerebrovascular diseases. Inulin, a type of fructan, has shown potential in improving atherosclerosis, although there are conflicting findings. It is hypothesized that the polymerization degree of inulin may largely influence its therapeutic effectiveness. Therefore, this study aimed to investigate the effects and mechanisms of short-chain and long-chain inulin in AS.

Methods

ApoE-/- mice fed a high fat diet (HFD) were used to establish an atherosclerosis model. These mice received daily oral administration of either short-chain or long-chain inulin for 12 weeks. Plasma lipid metabolism-related indices were measured using biochemical analysis, and plasma immunological indices were analyzed via ELISA. The aorta, aortic root regions, liver tissue, adipose tissue, and colon tissue were examined through various staining techniques, including ORO staining, hematoxylin and eosin staining, Alcian blue staining, and immunofluorescent or immunohistochemical assays. Microbiome analysis was conducted in the cecal content.

Results

The results indicated that both short-chain and long-chain inulin substantially reduced the formation of atherosclerotic plaques. Inulin also improved plasma lipid concentrations and hepatic lipid metabolism, and partially alleviated both localized (atherosclerotic lesions) and systemic inflammation. Short-chain inulin was more effective than long-chain inulin in reducing atherosclerotic plaques formation, enhancing lipid metabolism and reducing inflammation. Additionally, both types of inulin showed similar effectiveness in enhancing intestinal epithelial barrier integrity, gut microbiota composition and functionality.

Conclusion

These findings suggest that inulin has a protective role against atherosclerosis by enhancing lipid metabolism, reducing inflammation, and improving intestinal barrier and gut microbiota. As a dietary intervention, short-chain inulin is more effective than long-chain inulin, offering clinical implications for using inulin as a therapeutic agent for atherosclerosis.

Role of short-chain fatty acids in host physiology

Short-chain fatty acids (SCFAs) are major metabolites produced by the gut microbiota through the fermentation of dietary fiber, and they have garnered significant attention due to their close association with host health. As important mediators between the gut microbiota and the host, SCFAs serve as energy substrates for intestinal epithelial cells and maintain homeostasis in host immune and energy metabolism by influencing host epigenetics, activating G protein-coupled receptors, and inhibiting pathogenic microbial infections. This review provides a comprehensive summary of SCFAs synthesis and metabolism and offering an overview of the latest research progress on their roles in protecting gut health, enhancing energy metabolism, mitigating diseases such as cancer, obesity, and diabetes, modulating the gut-brain axis and gut-lung axis, and promoting bone health.

Nutritional Modulation of Host Defense Peptide Synthesis: A Novel Host-Directed Antimicrobial Therapeutic Strategy?

The escalating threat of antimicrobial resistance underscores the imperative for innovative therapeutic strategies. Host defense peptides (HDPs), integral components of innate immunity, exhibit profound antimicrobial and immunomodulatory properties. Various dietary compounds, such as short-chain fatty acids, vitamins, minerals, sugars, amino acids, phytochemicals, bile acids, probiotics, and prebiotics have been identified to enhance the synthesis of endogenous HDPs without provoking inflammatory response or compromising barrier integrity. Additionally, different classes of these compounds synergize in augmenting HDP synthesis and disease resistance. Moreover, dietary supplementation of several HDP-inducing compounds or their combinations have demonstrated robust protection in rodents, rabbits, pigs, cattle, and chickens from experimental infections. However, the efficacy of these compounds in inducing HDP synthesis varies considerably among distinct compounds. Additionally, the regulation of HDP genes occurs in a gene-specific, cell type-specific, and species-specific manner. In this comprehensive review, we systematically summarized the modulation of HDP synthesis and the mechanism of action attributed to each major class of dietary compounds, including their synergistic combinations, across a spectrum of animal species including humans. We argue that the ability to enhance innate immunity and barrier function without triggering inflammation or microbial resistance positions the nutritional modulation of endogenous HDP synthesis as a promising host-directed approach for mitigating infectious diseases and antimicrobial resistance. These HDP-inducing compounds, particularly in combinations, harbor substantial clinical potential for further exploration in antimicrobial therapies for both human and other animals.

Preclinical Evaluation of Sodium Butyrate's Potential to Reduce Alcohol Consumption: A Dose-Escalation Study in C57BL/6J Mice in Antibiotic-Enhanced Binge-Like Drinking Model

INTRODUCTION

In our earlier efforts to establish gut-brain axis during alcohol use disorder (AUD), we have demonstrated that supplementation of C57BL/6J male mice with 8 mg/mL sodium butyrate, a major short-chain fatty acid, in drinking water reduced ethanol intake and neuroinflammatory response in antibiotic (ABX)-enhanced voluntary binge-like alcohol consumption model, drinking in the dark (DID).

METHODS

To further evaluate the preclinical potential of SB, we have set a dose-escalation study in C57BL/6J male mice to test effects of ad libitum 20 mg/mL SB and 50 mg/mL SB and their combinations with ABX in the DID procedure for 4 weeks. Effects of these SB concentrations on ethanol consumption and bodily parameters were determined for the duration of the treatments. At the end of study, blood, liver, and intestinal tissues were collected to study any potential adverse effects ad to measure blood ethanol concentrations.

RESULTS

Increasing SB concentrations in the drinking water caused a loss in the protective effect against ethanol consumption and produced adverse effects on body and liver weights, reduced overall liquid intake. The hypothesis that these effects were due to aversion to SB smell/taste at these high concentrations were further tested in a follow up proof-of-concept study with intragastric gavage administration of SB. The higher gavage dose (320 mg/kg) caused reduction in ethanol consumption without any adverse effects.

CONCLUSION

Overall, these findings added more support for the therapeutic potential of SB in management of AUD, given a proper form of administration.

INTRODUCTION

In our earlier efforts to establish gut-brain axis during alcohol use disorder (AUD), we have demonstrated that supplementation of C57BL/6J male mice with 8 mg/mL sodium butyrate, a major short-chain fatty acid, in drinking water reduced ethanol intake and neuroinflammatory response in antibiotic (ABX)-enhanced voluntary binge-like alcohol consumption model, drinking in the dark (DID).

METHODS

To further evaluate the preclinical potential of SB, we have set a dose-escalation study in C57BL/6J male mice to test effects of ad libitum 20 mg/mL SB and 50 mg/mL SB and their combinations with ABX in the DID procedure for 4 weeks. Effects of these SB concentrations on ethanol consumption and bodily parameters were determined for the duration of the treatments. At the end of study, blood, liver, and intestinal tissues were collected to study any potential adverse effects ad to measure blood ethanol concentrations.

RESULTS

Increasing SB concentrations in the drinking water caused a loss in the protective effect against ethanol consumption and produced adverse effects on body and liver weights, reduced overall liquid intake. The hypothesis that these effects were due to aversion to SB smell/taste at these high concentrations were further tested in a follow up proof-of-concept study with intragastric gavage administration of SB. The higher gavage dose (320 mg/kg) caused reduction in ethanol consumption without any adverse effects.

CONCLUSION

Overall, these findings added more support for the therapeutic potential of SB in management of AUD, given a proper form of administration.

Berberine alleviates high-energy and low-protein diet-induced fatty liver hemorrhagic syndrome in laying hens: insights from microbiome and metabolomics

Berberine (BBR), a well-known quaternary ammonium alkaloid, is recognized for its ability to prevent and alleviate metabolic disorders because of its anti-oxidative and anti-inflammatory properties. However, the underlying mechanisms of BBR to mitigate fatty liver hemorrhagic syndrome (FLHS) through the modulation of gut microbiota and their metabolism remained unclear. The results revealed that BBR ameliorates lipid metabolism disorder in high-energy and low-protein (HELP) diet-induced FLHS laying hens, as evidenced by improved liver function and lipid deposition of the liver, reduced blood lipids, and the expression of liver lipid synthesis-related factors. Moreover, BBR alleviated HELP diet-induced barrier dysfunction, increased microbial population, and dysregulated lipid metabolism in the ileum. BBR reshaped the HELP-perturbed gut microbiota, particularly declining the abundance of Desulfovibrio_piger and elevating the abundance of Bacteroides_salanitronis_DSM_18170. Meanwhile, metabolomic profiling analysis revealed that BBR reshaped microbial metabolism and function, particularly by reducing the levels of hydrocinnamic acid, dehydroanonaine, and leucinic acid. Furthermore, fecal microbiota transplantation (FMT) experiments revealed that BBR-enriched gut microbiota alleviated hepatic lipid deposition and intestinal inflammation compared with those chicks that received a gut microbiota by HELP. Collectively, our study provided evidence that BBR effectively alleviated FLHS induced by HELP by reshaping the microbial and metabolic homeostasis within the liver-gut axis.

Molecular Mechanisms behind Obesity and Their Potential Exploitation in Current and Future Therapy

Obesity is a chronic disease caused primarily by the imbalance between the amount of calories supplied to the body and energy expenditure. Not only does it deteriorate the quality of life, but most importantly it increases the risk of cardiovascular diseases and the development of type 2 diabetes mellitus, leading to reduced life expectancy. In this review, we would like to present the molecular pathomechanisms underlying obesity, which constitute the target points for the action of anti-obesity medications. These include the central nervous system, brain-gut-microbiome axis, gastrointestinal motility, and energy expenditure. A significant part of this article is dedicated to incretin-based drugs such as GLP-1 receptor agonists (e.g., liraglutide and semaglutide), as well as the brand new dual GLP-1 and GIP receptor agonist tirzepatide, all of which have become "block-buster" drugs due to their effectiveness in reducing body weight and beneficial effects on the patient's metabolic profile. Finally, this review article highlights newly designed molecules with the potential for future obesity management that are the subject of ongoing clinical trials.

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

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

Dietary fiber induces a fat preference associated with the gut microbiota

Eating behavior is essential to human health. However, whether future eating behavior is subjected to the conditioning of preceding dietary composition is unknown. This study aimed to investigate the effect of dietary fiber consumption on subsequent nutrient-specific food preferences between palatable high-fat and high-sugar diets and explore its correlation with the gut microbiota. C57BL/6NJcl male mice were subjected to a 2-week dietary intervention and fed either a control (n = 6) or inulin (n = 6) diet. Afterward, all mice were subjected to a 3-day eating behavioral test to self-select from the simultaneously presented high-fat and high-sugar diets. The test diet feed intakes were recorded, and the mice's fecal samples were analyzed to evaluate the gut microbiota composition. The inulin-conditioned mice exhibited a preference for the high-fat diet over the high-sugar diet, associated with distinct gut microbiota composition profiles between the inulin-conditioned and control mice. The gut microbiota Oscillospiraceae sp., Bacteroides acidifaciens, and Clostridiales sp. positively correlated with a preference for fat. Further studies with fecal microbiota transplantation and eating behavior-related neurotransmitter analyses are warranted to establish the causal role of gut microbiota on host food preferences. Food preferences induced by dietary intervention are a novel observation, and the gut microbiome may be associated with this preference.

The Role of Short Chain Fatty Acids in Inflammation and Body Health

Short chain fatty acids (SCFAs), mainly including acetate, propionate and butyrate, are produced by intestinal bacteria during the fermentation of partially digested and indigestible polysaccharides. SCFAs play an important role in regulating intestinal energy metabolism and maintaining the homeostasis of the intestinal environment and also play an important regulatory role in organs and tissues outside the gut. In recent years, many studies have shown that SCFAs can regulate inflammation and affect host health, and two main signaling mechanisms have also been identified: the activation of G-protein coupled receptors (GPCRs) and inhibition of histone deacetylase (HDAC). In addition, a growing body of evidence highlights the importance of every SCFA in influencing health maintenance and disease development. In this review, we summarized the recent advances concerning the biological properties of SCFAs and their signaling pathways in inflammation and body health. Hopefully, it can provide a systematic theoretical basis for the nutritional prevention and treatment of human diseases.

Significance of CD10 for Mucosal Immunomodulation by β-Casomorphin-7 in Exacerbation of Ulcerative Colitis

β-Casomorphin-7 (BCM), a breakdown product of milk β-casein, exhibits opioid activity. Opioids are known to affect the immune system, but the effects of BCM on ulcerative colitis (UC) are not clear. We examined the effects of BCM on mucosal immunity using a mouse dextran sulfate sodium-induced colitis model and an in vitro CD8+ T cell activation model. Human UC patients were examined to reveal the relationship between CD10 and mucosal immunity. Combined treatment of the colitis model with thiorphan (TOP) inhibited BCM degradation by suppressing CD10 in the intestinal mucosa, activating mouse mucosal CD8, and suppressing CD4 and Treg. In the CD8+ T cell in vitro activation assay using mouse splenocytes, BCM inhibited the oxidative phosphorylation (OXPHOS) of CD8+ T cells and induced the glycolytic pathway, promoting their activation. Conversely, in a culture system, BCM suppressed OXPHOS and decreased defensin α production in IEC6 mouse intestinal epithelial cells. In the mouse model, BCM reduced defensin α and butyrate levels in the colonic mucosa. During the active phase of human ulcerative colitis, the downward regulation of ileal CD10 expression by CpG methylation of the gene promoter was observed, resulting in increased CD8 activation and decreased defensin α and butyrate levels. BCM is a potential aggravating factor for UC and should be considered in the design of dietary therapy. In addition, decreased CD10 expression may serve as an indicator of UC activity and recurrence, but further clinical studies are needed.

The use of an in vitro fecal fermentation model to uncover the beneficial role of omega-3 and punicic acid in gut microbiota alterations induced by a Western diet

The influence of gut microbiota in the onset and development of several metabolic diseases has gained attention over the last few years. Diet plays an essential role in gut microbiota modulation. Western diet (WD), characterized by high-sugar and high-fat consumption, alters gut microbiome composition, diversity index, microbial relative levels, and functional pathways. Despite the promising health effects demonstrated by polyunsaturated fatty acids, their impact on gut microbiota is still overlooked. The effect of Fish oil (omega-3 source) and Pomegranate oil (punicic acid source), and a mixture of both oils in gut microbiota modulation were determined by subjecting the oil samples to in vitro fecal fermentations. Cecal samples from rats from two different dietary groups: a control diet (CD) and a high-fat high-sugar diet (WD), were used as fecal inoculum. 16S amplicon metagenomics sequencing showed that Fish oil + Pomegranate oil from the WD group increased α-diversity. This sample can also increase the relative abundance of the Firmicutes and Bacteroidetes phylum as well as Akkermansia and Blautia, which were affected by the WD consumption. All samples were able to increase butyrate and acetate concentration in the WD group. Moreover, tyrosine concentrations, a precursor for dopamine and norepinephrine, increase in the Fish oil + Pomegranate oil WD sample. GABA, an important neurotransmitter, was also increased in WD samples. These results suggest a potential positive impact of these oils' mixture on gut-brain axis modulation. It was demonstrated, for the first time, the great potential of using a mixture of both Fish and Pomegranate oil to restore the gut microbiota changes associated with WD consumption.

Butyrate as a potential therapeutic agent for neurodegenerative disorders

Maintaining an optimum microbial community within the gastrointestinal tract is intricately linked to human metabolic, immune and brain health. Disturbance to these microbial populations perturbs the production of vital bioactive compounds synthesised by the gut microbiome, such as short-chain fatty acids (SCFAs). Of the SCFAs, butyrate is known to be a major source of energy for colonocytes and has valuable effects on the maintenance of intestinal epithelium and blood brain barrier integrity, gut motility and transit, anti-inflammatory effects, and autophagy induction. Inducing endogenous butyrate production is likely to be beneficial for gut-brain homeostasis and for optimal neuronal function. For these reasons, butyrate has gained interest as a potential therapy for not only metabolic and immunological disorders, but also conditions related to the brain, including neurodegenerative diseases. While direct and indirect sources of butyrate, including prebiotics, probiotics, butyrate pro-drugs and glucosidase inhibitors, offer a promising therapeutic avenue, their efficacy and dosage in neurodegenerative conditions remain largely unknown. Here, we review current literature on effects of butyrate relevant to neuronal function, the impact of butyrate in a range of neurodegenerative diseases and related treatments that may have potential for the treatment of neurodegenerative diseases.

Developmental Programming of the Fetal Immune System by Maternal Western-Style Diet: Mechanisms and Implications for Disease Pathways in the Offspring

Maternal obesity and over/undernutrition can have a long-lasting impact on offspring health during critical periods in the first 1000 days of life. Children born to mothers with obesity have reduced immune responses to stimuli which increase susceptibility to infections. Recently, maternal western-style diets (WSDs), high in fat and simple sugars, have been associated with skewing neonatal immune cell development, and recent evidence suggests that dysregulation of innate immunity in early life has long-term consequences on metabolic diseases and behavioral disorders in later life. Several factors contribute to abnormal innate immune tolerance or trained immunity, including changes in gut microbiota, metabolites, and epigenetic modifications. Critical knowledge gaps remain regarding the mechanisms whereby these factors impact fetal and postnatal immune cell development, especially in precursor stem cells in bone marrow and fetal liver. Components of the maternal microbiota that are transferred from mothers consuming a WSD to their offspring are understudied and identifying cause and effect on neonatal innate and adaptive immune development needs to be refined. Tools including single-cell RNA-sequencing, epigenetic analysis, and spatial location of specific immune cells in liver and bone marrow are critical for understanding immune system programming. Considering the vital role immune function plays in offspring health, it will be important to understand how maternal diets can control developmental programming of innate and adaptive immunity.