The gut microbiota at the intersection of diet and human health

Gut microbiota and derived metabolites mediate obstructive sleep apnea induced atherosclerosis

Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia/hypercapnia (IHC), affects predominantly obese individuals, and increases atherosclerosis risk. Since we and others have implicated gut microbiota and metabolites in atherogenesis, we dissected their contributions to OSA-induced atherosclerosis. Atherosclerotic lesions were compared between conventionally-reared specific pathogen free (SPF) and germ-free (GF) Apoe-/- mice following a high fat high cholesterol diet (HFHC), with and without IHC conditions. The fecal microbiota and metabolome were profiled using 16S rRNA gene amplicon sequencing and untargeted tandem mass spectrometry (LC-MS/MS) respectively. Phenotypic data showed that HFHC significantly increased atherosclerosis as compared to regular chow (RC) in both aorta and pulmonary artery (PA) of SPF mice. IHC exacerbated lesions in addition to HFHC. Differential abundance analysis of gut microbiota identified an enrichment of Akkermansiaceae and a depletion of Muribaculaceae (formerly S24-7) family members in the HFHC-IHC group. LC-MS/MS showed a dysregulation of bile acid profiles with taurocholic acid, taurodeoxycholic acid, and 12-ketodeoxycholic acid enriched in the HFHC-IHC group, long-chain N-acyl amides, and phosphatidylcholines. Interestingly, GF Apoe-/- mice markedly reduced atherosclerotic formation relative to SPF Apoe-/- mice in the aorta under HFHC/IHC conditions. In contrast, microbial colonization did not show a significant impact on the atherosclerotic progression in PA. In summary, this research demonstrated that (1) IHC acts cooperatively with HFHC to induce atherosclerosis; (2) gut microbiota modulate atherogenesis, induced by HFHC/IHC, in the aorta not in PA; (3) different analytical methods suggest that a specific imbalance between Akkermansiaceae and Muribaculaceae bacterial families mediate OSA-induced atherosclerosis; and (4) derived bile acids, such as deoxycholic acid and lithocholic acid, regulate atherosclerosis in OSA. The knowledge obtained provides novel insights into the potential therapeutic approaches to prevent and treat OSA-induced atherosclerosis.

Gut microbiota and endometrial cancer: research progress on the pathogenesis and application

As one of the three major malignant tumors in women, the morbidity of endometrial cancer is second only to that of cervical cancer and is increasing yearly. Its etiological mechanism is not clear, and the risk factors are numerous and common and are closely related to obesity, hypertension, diabetes, etc. The gut microbiota has many strains, which play a considerable part in normal digestion and absorption in the human body and the regulation of the immune response. In the last few years, research on the gut microbiota has been unprecedentedly popular, and it has been confirmed that the gut microbiota closely correlates with the occurrence and development of all kinds of benign and malignant diseases. In this article, the effects of the gut microbiota and its metabolites on the occurrence and development of endometrial cancer is reviewed, and its application in the prevention, diagnosis and treatment of endometrial cancer is explored.

Faecalibacterium prausnitzii regulates carbohydrate metabolic functions of the gut microbiome in C57BL/6 mice

The probiotic impact of microbes on host metabolism and health depends on both host genetics and bacterial genomic variation. Faecalibacterium prausnitzii is the predominant human gut commensal emerging as a next-generation probiotic. Although this bacterium exhibits substantial intraspecies diversity, it is unclear whether genetically distinct F. prausnitzii strains might lead to functional differences in the gut microbiome. Here, we isolated and characterized a novel F. prausnitzii strain (UT1) that belongs to the most prevalent but underappreciated phylogenetic clade in the global human population. Genome analysis showed that this butyrate-producing isolate carries multiple putative mobile genetic elements, a clade-specific defense system, and a range of carbohydrate catabolic enzymes. Multiomic approaches were used to profile the impact of UT1 on the gut microbiome and associated metabolic activity of C57BL/6 mice at homeostasis. Both 16S rRNA and metagenomic sequencing demonstrated that oral administration of UT1 resulted in profound microbial compositional changes including a significant enrichment of Lactobacillus, Bifidobacterium, and Turicibacter. Functional profiling of the fecal metagenomes revealed a markedly higher abundance of carbohydrate-active enzymes (CAZymes) in UT1-gavaged mice. Accordingly, UT1-conditioned microbiota possessed the elevated capability of utilizing starch in vitro and exhibited a lower availability of microbiota-accessible carbohydrates in the gut. Further analysis uncovered a functional network wherein UT1 reduced the abundance of mucin-degrading CAZymes and microbes, which correlated with a concomitant reduction of fecal mucin glycans. Collectively, our results reveal a crucial role of UT1 in facilitating the carbohydrate metabolism of the gut microbiome and expand our understanding of the genetic and phenotypic diversity of F. prausnitzii.

Gut-brain axis modulation by sudachi peel extract enhances resilience to chronic social defeat stress in mice

BACKGROUND

Sudachitin, an anti-inflammatory compound from Citrus sudachi peel, may influence stress resilience. We examined whether sudachi peel extract affects depression-like behaviors and gut microbiota dysbiosis in mice subjected to chronic social defeat stress (CSDS).

METHODS

First, we examined the effect of sudachitin on depression-like behavior and plasma interleukin-6 (IL-6) levels following lipopolysaccharide (LPS, 0.5 mg/kg) administration. Next, we investigated whether supplementation with sudachi peel extract could modulate the gut microbiota dysbiosis induced by CSDS.

RESULTS

Sudachitin prevented LPS-induced depression-like behavior and the rise in plasma IL-6. In control mice, CSDS increased IL-6, induced splenomegaly, and caused anhedonia-like behavior. These changes were absent in the sudachi peel extract group. Although alpha-diversity of the gut microbiota remained abnormal under CSDS, beta-diversity was significantly altered by sudachi peel extract. Moreover, plasma IL-6 levels and Iba1 expression in the prefrontal cortex correlated with the relative abundance of certain gut bacteria.

LIMITATIONS

The exact mechanisms behind the resilience-promoting effects of sudachi peel extract remain unclear.

CONCLUSION

Sudachi peel extract supplementation enhances resilience to CSDS by preventing anhedonia, reducing plasma IL-6 levels and splenomegaly, and modulating gut microbiota composition. Further research is needed to clarify these anti-inflammatory pathways and the roles of additional pro-inflammatory cytokines.

Benefits of inulin and fructo-oligosaccharides on high fat diet-induced type 2 diabetes mellitus by regulating the gut microbiota in mice

Type 2 diabetes mellitus (T2DM) is pathologically associated with gut microbiota imbalance, which is implicated in disease progression through metabolic and inflammatory pathways. The therapeutic potential of inulin, a well-characterized prebiotic, has been explored to mitigate T2DM via microbiota modulation. However, the efficacy of this intervention, with its performance dependent on the degree of polymerization (DP), requires further investigation. This study assessed the therapeutic roles of inulin (DP3-60) and fructo-oligosaccharides (FOS, DP3-10) in T2DM management. Dietary administration of these prebiotic compounds demonstrated a significant capacity to alleviate multiple metabolic pathologies, including obesity, insulin resistance, systemic inflammation, oxidative stress, dyslipidemia and hepatic steatosis in high-fat diet (HFD)-fed induced T2DM mice. Significant superior efficacy was observed in FOS for ameliorating glucose metabolic dysregulation, adipocyte hypertrophy, liver weight, and histopathological alterations in colonic tissue, while inulin exhibited greater potency in alleviating oxidative stress. Both inulin and FOS enhanced gut microbiota diversity and richness in T2DM mice, accompanied by a significant reduction in Firmicutes/Bacteroidetes ratio. Notably, the S24-7 family emerged as a crucial microbial taxon modulated by both inulin and FOS. Furthermore, FOS demonstrated superior capacity to restore HFD-induced gut microbiota. Taxonomically significant amplicon sequence variants (ASVs), which were altered by HFD and modulated by inulin and FOS, exhibited distinct taxonomic profiles between the two compounds. This study provides preliminary evidence that the biological effects and beneficial properties of inulin-type fructans exhibit DP-dependent variations, which may enhance their efficient utilization in metabolic disorders.

Impact of dietary carbohydrate, fat or protein restriction on the human gut microbiome: a systematic review

Restriction of dietary carbohydrates, fat and/or protein is often used to reduce body weight and/or treat (metabolic) diseases. Since diet is a key modulator of the human gut microbiome, which plays an important role in health and disease, this review aims to provide an overview of current knowledge of the effects of macronutrient-restricted diets on gut microbial composition and metabolites. A structured search strategy was performed in several databases. After screening for inclusion and exclusion criteria, thirty-six articles could be included. Data are included in the results only when supported by at least three independent studies to enhance the reliability of our conclusions. Low-carbohydrate (<30 energy%) diets tended to induce a decrease in the relative abundance of several health-promoting bacteria, including Bifidobacterium, as well as a reduction in short-chain fatty acid (SCFA) levels in faeces. In contrast, low-fat diets (<30 energy%) increased alpha diversity, faecal SCFA levels and abundance of some beneficial bacteria, including Faecalibacterium prausnitzii. There were insufficient data to draw conclusions concerning the effects of low-protein (<10 energy%) diets on gut microbiota. Although the data of included studies unveil possible benefits of low-fat and potential drawbacks of low-carbohydrate diets for human gut microbiota, the diversity in study designs made it difficult to draw firm conclusions. Using a more uniform methodology in design, sample processing and sharing raw sequence data could foster our understanding of the effects of macronutrient restriction on gut microbiota composition and metabolic dynamics relevant to health. This systematic review was registered at https://www.crd.york.ac.uk/prospero as CRD42020156929.

Gut microbiome diversity is associated with muscle mass, strength and quality in post-stroke patients

BACKGROUND

The gut microbiome has emerged as a potential influencer of muscle health; however, its role in hospitalized patients remains unclear. This study aimed to investigate the association between gut microbiome diversity and skeletal muscle mass, strength, and quality in hospitalized post-stroke patients.

METHODS

We conducted a cross-sectional study of post-stroke patients admitted to a rehabilitation facility. Gut microbiome diversity was assessed using 16S ribosomal ribonucleic acid (rRNA) gene sequencing, calculating Operational Taxonomic Unit (OTU) Richness, Faith's Phylogenetic Diversity (PD), and Shannon index. Muscle health was evaluated using skeletal muscle index (SMI) for muscle mass, handgrip strength (HGS) for muscle strength, and bioimpedance analysis-derived phase angle (PhA) for muscle quality. Multiple linear regression analyses were performed, adjusting for potential confounders.

RESULTS

A total of 156 patients (mean age 78.4 years; 55.7 % male) were analyzed. OTU Richness showed significant positive associations with SMI (β = 0.197, p = 0.025), HGS (β = 0.180, p = 0.005), and PhA (β = 0.178, p = 0.022). The Shannon index was also positively associated with SMI (β = 0.120, p = 0.041), HGS (β = 0.140, p = 0.028), and PhA (β = 0.164, p = 0.032). Faith's PD did not demonstrate significant associations with muscle health parameters.

CONCLUSIONS

Higher gut microbiome diversity, assessed by OTU Richness and Shannon index, is associated with better muscle mass, strength, and quality in post-stroke patients. These findings suggest a potential role for gut microbiota in muscle health during stroke rehabilitation.

Impact of gender and reproductive states on diets and intestinal microbiota in Pratt's leaf-nosed bats (Hipposideros pratti)

Lactation represents a critical evolutionary adaptation in mammals, imposing heightened nutritional demands that drive shifts in foraging behavior and intestinal microbiota to optimize nutrient acquisition. In the sexually dimorphic Pratt's leaf-nosed bat (Hipposideros pratti), males exhibit enlarged transverse lobes posterior to the nasal leaf, a morphological trait may influence echolocation dynamics and dietary niche partitioning. This provides an opportunity to examine dietary and microbiota differences between genders and across various reproductive states. Using high-throughput sequencing of fecal samples from male (HPM), non-lactating female (HPF), and lactating female (HPFL) H. pratti collected in late June, we identified gender- and physiology-linked ecological strategies. While dietary diversity indices showed no significant intergroup differences, compositional analysis revealed distinct prey preferences: both HPM and HPFL predominantly consumed Coleoptera, whereas HPF favored Diptera. Coleoptera's larger size and nutrient profile-rich in leucine, isoleucine, and chitin-likely optimize energy efficiency for HPFL, reducing foraging effort while supplying amino acids critical for mammary gland function and immunity. Gender-based differences were observed in intestinal microbiota diversity, with females demonstrating higher diversity indices compared to males. Males showed a notable abundance of Clostridium sensu stricto 1, a proteolytic genus associated with Coleoptera digestion but linked to inflammatory risks via pathogenic strains. The HPFL group exhibited microbiota enriched in Lactococcus (chitinolytic taxa) and lactation-adapted symbionts: Lachnoclostridium may suppress pro-inflammatory responses via acetate production, while Pseudonocardia may enhance calcium homeostasis and antimicrobial defense. This study advances understanding of host-microbe coadaptation in mitigating life-history trade-offs and highlights ecological drivers of microbiota plasticity in insectivorous bats.

Harnessing Probiotics: Exploring the Role of the Gut Microbiome in Combating Obesity

Obesity has become a global health crisis driven by genetic, environmental, and lifestyle factors, often linked to gut microbiome imbalances. Probiotics, particularly Lactobacillus and Bifidobacterium strains, have shown promise in clinical trials by promoting weight loss, improving lipid profiles, and addressing gut dysbiosis associated with obesity. This review surveys the literature on the microbiome and obesity, emphasizing the clinical relevance of probiotics in treatment strategies. Our comprehensive PubMed search highlights the mechanisms through which probiotics influence metabolic health, including their effects on inflammation and appetite regulation. We also explore promising future research directions and the potential for integrating probiotics into clinical practice. While results are encouraging, the evidence is limited by strain variability, small sample sizes, short trial durations, and individual differences in microbiota composition. More extensive, long-term studies with standardized methods are crucial to confirm the effectiveness of probiotics as viable anti-obesity treatments.

The gut-brain axis in early Parkinson's disease: from prodrome to prevention

Parkinson's disease is the second most common neurodegenerative disorder and fastest growing neurological condition worldwide, yet its etiology and progression remain poorly understood. This disorder is characterized pathologically by the prion-like spread of misfolded neuronal alpha-synuclein proteins in specific brain regions leading to Lewy body formation, neurodegeneration, and progressive neurological impairment. It is unclear what triggers Parkinson's and where α-synuclein protein aggregation begins, although proposed induction sites include the olfactory bulb and dorsal motor nucleus of the vagus nerve. Within the last 20 years, there has been increasing evidence that Parkinson's could be triggered by early microbiome changes and α-synuclein accumulation in the gastrointestinal system. Gut microbiota dysbiosis that alters gastrointestinal motility, permeability, and inflammation could enable prion-like spread of α-synuclein from the gut-to-brain via the enteric nervous system. Individuals with isolated rapid eye movement sleep behavior disorder have a high likelihood of developing Parkinson's and might represent a prodromal 'gut-first' subtype of the condition. The gut-first model of Parkinson's offers novel gut-based therapeutic avenues, such as anti-, pre-, and pro-biotic preparations and fecal microbiota transplants. Crucially, gut-based interventions offer an avenue to treat Parkinson's at early prodromal stages with the aim of mitigating evolution to clinically recognizable Parkinson's disease characterized by motor impairment.

MetaBiome: a multiscale model integrating agent-based and metabolic networks to reveal spatial regulation in gut mucosal microbial communities

Mucosal microbial communities (MMCs) are complex ecosystems near the mucosal layers of the gut essential for maintaining health and modulating disease states. Despite advances in high-throughput omics technologies, current methodologies struggle to capture the dynamic metabolic interactions and spatiotemporal variations within MMCs. In this work, we present MetaBiome, a multiscale model integrating agent-based modeling (ABM), finite volume methods, and constraint-based models to explore the metabolic interactions within these communities. Integrating ABM allows for the detailed representation of individual microbial agents each governed by rules that dictate cell growth, division, and interactions with their surroundings. Through a layered approach-encompassing microenvironmental conditions, agent information, and metabolic pathways-we simulated different communities to showcase the potential of the model. Using our in-silico platform, we explored the dynamics and spatiotemporal patterns of MMCs in the proximal small intestine and the cecum, simulating the physiological conditions of the two gut regions. Our findings revealed how specific microbes adapt their metabolic processes based on substrate availability and local environmental conditions, shedding light on spatial metabolite regulation and informing targeted therapies for localized gut diseases. MetaBiome provides a detailed representation of microbial agents and their interactions, surpassing the limitations of traditional grid-based systems. This work marks a significant advancement in microbial ecology, as it offers new insights into predicting and analyzing microbial communities.IMPORTANCEOur study presents a novel multiscale model that combines agent-based modeling, finite volume methods, and genome-scale metabolic models to simulate the complex dynamics of mucosal microbial communities in the gut. This integrated approach allows us to capture spatial and temporal variations in microbial interactions and metabolism that are difficult to study experimentally. Key findings from our model include the following: (i) prediction of metabolic cross-feeding and spatial organization in multi-species communities, (ii) insights into how oxygen gradients and nutrient availability shape community composition in different gut regions, and (iii) identification of spatiallyregulated metabolic pathways and enzymes in E. coli. We believe this work represents a significant advance in computational modeling of microbial communities and provides new insights into the spatial regulation of gut microbiome metabolism. The multiscale modeling approach we have developed could be broadly applicable for studying other complex microbial ecosystems.

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.

Exploring the Impact of Intermittent Fasting on Vascular Function and the Immune System: A Narrative Review and Novel Perspective

Vascular function is a critical determinant of cardiovascular health and all-cause mortality. Recent studies have suggested that intermittent fasting, a popular dietary strategy, elicits beneficial effects on vascular function. These studies also suggest that fasting-mediated improvements in vascular function coincide with reductions in systemic inflammation. However, the mechanisms that connect fasting, the immune system, and vascular function remain largely underexplored. The current review summarizes the effects of different intermittent fasting modalities on vascular health, focusing on endothelial dysfunction and arterial stiffness, 2 critical indices of vascular function. Improvements in vascular function are associated with reduced inflammation and are mechanistically linked to decreased circulating immune cells and their accumulation within the vascular wall and perivascular tissue. Recent data show that fasting redistributes circulating and tissue-resident immune cells to the bone marrow, affecting their inflammatory actions. However, there is no direct evidence relating immune cell redistribution to cardiovascular health. By relating fasting-induced immune cell redistribution to reduced inflammation and improved vascular function, we propose an exciting avenue of further exploration is determining whether fasting-induced immune cell redistribution impacts cardiovascular health.

Peptidoglycan isolated from the fruit of Lycium barbarum alleviates liver fibrosis in mice by regulating the TGF-β/Smad7 signaling and gut microbiota

The hepatoprotective effect of the fruit of Lycium barbarum has been documented in China over millennia. Lycium barbarum polysaccharides (LBPs) were the first macromolecules reported to mitigate liver fibrosis in carbon tetrachloride (CCl4)-treated mice. Herein, a neutral peptidoglycan, named as LBPW, was extracted from the fruit of Lycium barbarum. In this study, we investigated the hepatoprotective mechanisms of LBPW. CCl4-induced liver fibrosis mice were administered LBPW (50, 100, 200 mg ·kg-1 ·d-1, i.p.) or (100, 200, 300 mg· kg-1 ·d-1, i.g.) for 6 weeks. We showed that either i.p. or i.g. administration of LBPW dose-dependently attenuated liver damage and fibrosis in CCl4-treated mice. Pharmacokinetic analysis showed that cyanine 5.5 amine (Cy5.5)-labeled LBPW (Cy5.5-LBPW) could be detected in the liver through i.p. and i.g. administration with i.g.-administered Cy5.5-LBPW mainly accumulating in the intestine. In TGF-β1-stimulated LX-2 cells as well as in the liver of CCl4-treated mice, we demonstrated that LBPW significantly upregulated Smad7, a negative regulator of TGF-β/Smad signaling, to retard the activation of hepatic stellate cells (HSCs) and prevent liver fibrosis. On the other hand, LBPW significantly boosted the abundance of Akkermansia muciniphila (A. muciniphila) and fortified gut barrier function. We demonstrated that A. muciniphila might be responsible for the efficacy of LBPW since decreasing the abundance of this bacterium by antibiotics (Abs) blocked the effectiveness of LBPW. Overall, our results show that LBPW may exert the hepatoprotective effect via rebalancing TGF-β/Smad7 signaling and propagating gut commensal A. muciniphila, suggesting that LBPW could be leading components to be developed as new drug candidates or nutraceuticals against liver fibrosis.

Gut-Microbiota-Related Metabolite Phenylacetylglutamine and Risk of Incident Coronary Heart Disease Among Women

CONTEXT

Phenylacetylglutamine (PAGln) is a novel metabolite derived from gut microbial metabolism of dietary proteins, specifically phenylalanine, which may be linked to risks of adverse cardiovascular events.

OBJECTIVE

We investigated whether higher plasma levels of PAGln were associated with a greater risk of incident coronary heart disease (CHD) and tested whether adherence to a plant-based diet, which characterizes habitual dietary patterns of animal and plant food intake, modified the associations.

METHODS

We examined associations between plasma PAGln and risk of incident CHD over 11 to 16 years in a nested case-control study of 1520 women (760 incident cases and 760 controls) from the Nurses' Health Study. Separately, we analyzed relations between PAGln and dietary intakes measured through dietary records in the Women's Lifestyle Validation Study (n = 725).

RESULTS

Higher PAGln levels were related to a greater risk of CHD (P < .05 for dose-response relationship). Higher PAGln was associated with greater red/processed meat intake and lower vegetable intake (P < .05 for all). We found a significant interaction between PAGln and adherence to plant-based diet index (PDI) on CHD (Pinteraction = .008); higher PAGln levels were associated with an increased risk of CHD (relative risk per 1 SD: 1.22 [95% CI: 1.05, 1.41]) among women with low PDI but not among those with high PDI.

CONCLUSION

Higher PAGln was associated with higher risk of CHD, particularly in women with dietary patterns of eating more animal foods and fewer plant-based foods. Adherence to plant-based diets might attenuate unfavorable associations between a novel microbial metabolite and CHD risk.

Associations of breakfast habits and breakfast quality with depression symptoms: A cross-sectional study based on NHANES 2007-2018

BACKGROUND

Breakfast, often considered the most important meal of the day, affects both physical and mental health. While most studies focused on the effects of skipping breakfast on depression, few explored the roles of breakfast quality and breakfast time. The study aimed to investigate the association of breakfast habits and breakfast quality with depression symptoms.

METHODS

This study included 23,839 participants aged 20 and older from the 2007-2018 National Health and Nutrition Examination Survey (NHANES). Breakfast habits were assessed using two 24-h dietary recalls, capturing both whether and when breakfast was consumed. Breakfast quality was assessed by calculating the Breakfast Quality Score (BQS). Depression symptoms was diagnosed using the Patient Health Questionnaire (PHQ-9). Binary logistic regression was used to explore the associations.

RESULTS

Compared to participants who did not report breakfast, the ORs of participants who reported breakfast on both one recall and both recalls were 0.737(0.591,0.919) and 0.766(0.624,0.939) for depression symptoms. Compared to participants in the BQS T1 subgroup, the ORs of participants in the T2 subgroup and T3 subgroup were 0.895(0.723,1.108) and 0.716(0.564,0.908) for depression symptoms (P for trend = 0.013). Compared to participants who had breakfast before 8:00 AM, the ORs for depression symptoms were 1.104 (95 % CI: 0.888, 1.371) for those who had breakfast between 8:00-9:00 AM and 1.278 (95 % CI: 1.030, 1.587) for those who had breakfast after 9:00 AM.

CONCLUSIONS

Skipping breakfast, low breakfast quality, and late breakfast are independently associated with depression symptoms.

Astragalus polysaccharide reduces the severity of acute pancreatitis under a high-fat diet through enriching L. reuteri and propionate

Acute pancreatitis (AP) is a severe digestive disorder, worsened by a high-fat diet (HFD) through inflammation and gut microbiota disruption. Astragalus polysaccharides (APS), known for their anti-inflammatory properties, may alleviate HFD-induced exacerbation of AP by modulating gut microbiota. This study investigates the effect of APS on AP severity under a HFD (HAP). Results show that HFD significantly worsens AP, with elevated serum enzymes, pro-inflammatory cytokines, and pancreatic damage. Single-cell RNA sequencing revealed increased ICAM1+ neutrophils and activation of the NF-κB/necroptosis pathway in HAP mice. Treatment with APS reduced neutrophil infiltration, downregulated NF-κB, and suppressed necroptosis. APS also restored gut microbiota balance, boosting Lactobacillus reuteri (L. reuteri) and propionate (PA) levels. Interventions with L. reuteri or PA reduced HAP severity, with combined treatment showing synergistic effects. These findings suggest that the protective effect of APS is mediated by microbiota-dependent mechanisms, highlighting the gut-pancreas axis as a potential therapeutic target for AP.

Systemic inflammation is associated with gut microbiota diversity in post-stroke patients

BACKGROUND

There is growing interest in gut microbiota and health outcomes. However, the relationship between systemic inflammation and gut microbiota diversity in hospitalized patients remains unclear. This study aimed to investigate the association in post-stroke rehabilitation patients.

METHODS

A cross-sectional study was conducted on post-stroke patients admitted to a rehabilitation hospital. Systemic inflammation was assessed using the modified Glasgow Prognostic Score (mGPS). Gut microbiota diversity was evaluated using three indices: Shannon index, Operational Taxonomic Unit (OTU) richness, and Faith's Phylogenetic Diversity (PD). Multiple linear regression analyses were performed to examine the relationship between mGPS and gut microbiota diversity indices, adjusting for potential confounders.

RESULTS

A total of 156 patients (mean age 78.4 years; 55.7% men) were analyzed. The median mGPS was 0 (interquartile range: 0-1), with GPS distribution: 61.8% scored 0, 25.7% scored 1, and 12.5% scored 2. After adjusting for confounders, mGPS was significantly and negatively associated with the Shannon index (B = -0.143, 95% CI -0.288 to -0.002, β = -0.177) and OTU richness (B = -17.832, 95% CI -24.349 to -3.951, β = -0.208). However, no significant association was observed between mGPS and Faith's PD (B = -1.155, 95% CI -2.464 to 0.189, β = -0.155).

CONCLUSION

This study demonstrates a significant negative association between systemic inflammation and both quantitative and qualitative gut microbiota diversity in post-stroke patients.

Trimethylamine N-Oxide Plasma Levels Following Red Meat and Cod Fish Intake: A Pilot Crossover Trial in Hemodialysis Patients

SCOPE

The uremic toxin trimethylamine N-oxide (TMAO) accumulates in patients with chronic kidney disease (CKD) and is associated with its progression, cardiovascular disease, and other complications. The gut microbiota produces TMAO from substrates mainly found in red meat, eggs, and dairy. However, some saltwater fish also contain high levels of TMAO. Although fish consumption is generally linked to beneficial effects, its effects on CKD patients require further research.

METHODS AND RESULTS

This study compares the effect of red meat and cod fish intake on TMAO plasma levels in CKD patients undergoing hemodialysis (HD). Participants received a single animal protein source (red meat vs. cod fish) for lunch and dinner for four consecutive days (each intervention), with a 2-week washout period in between. TMAO plasma levels were analyzed using LC-MS/MS. All 14 patients concluded the red meat intervention, while one refused to participate in the fish intervention. No significant difference in TMAO plasma levels was found post-red meat (p = 0.21) or fish intervention (p = 0.91), as well as between groups (p = 0.43).

CONCLUSION

In this study, 4 days of red meat and cod fish intake did not significantly impact TMAO levels in HD patients, while other factors may be associated with their circulating levels.

Gut microbiome diversity and nutrition intake in post-stroke patients

AIM

This study aimed to investigate the association between energy intake and gut microbiome diversity in patients following stroke.

METHODS

A cross-sectional study was conducted with 156 patients following stroke aged ≥65 years admitted to a rehabilitation hospital (mean age, 78 ± 7 years; 69 women). Energy intake was calculated from average food consumption during the first week after admission. Gut microbiome diversity was assessed using three indices derived from 16S rRNA sequencing of stool samples: the Shannon index, operational taxonomic unit (OTU) richness and Faith's phylogenetic diversity (PD). Sex-stratified multiple linear regression analysis evaluated the association between energy intake and gut microbiome diversity, adjusting for confounders such as age, body weight, inflammation markers, nutritional status, and medication.

RESULTS

The study included 156 patients following stroke (mean age, 78 ± 7 years; 69 women). The median energy intake was 1600 (interquartile range [IQR], 1400-1800] kcal/day for all participants. The median for gut microbiome diversity indices were Shannon index, 6.3 (IQR, 5.9-6.5); OTU richness, 217.3 (IQR, 181.9-258.1); and Faith's PD, 22.4 (IQR, 19.3-27.2). In women, energy intake was significantly positively associated with the Shannon index (β = 0.233, P = 0.026), OTU richness (β = 0.228, P = 0.036), and Faith's PD (β = 0.212, P = 0.038). In men, energy intake was significantly positively associated with the Shannon index (β = 0.230, P = 0.027), OTU richness (β = 0.211, P = 0.040), and Faith's PD (β = 0.198, P = 0.043).

CONCLUSIONS

Adequate energy intake may play an important role in preserving gut microbiome diversity in patients. Further longitudinal studies are needed to confirm these associations, clarify causality, and explore underlying mechanisms. Geriatr Gerontol Int 2025; 25: 535-542.

The role of colonic microbiota amino acid metabolism in gut health regulation

The human gut microbiota plays a critical role in maintaining host homeostasis through metabolic activities. Among these, amino acid (AA) metabolism by the microbiota in the large intestine is highly heterogeneous and relevant to host health. Despite increasing interest, microbial AA metabolism remains relatively unexplored. This review highlights recent advances in colonic microbial AA metabolism, including auxotrophies, AA synthesis, and dissimilatory AA metabolites, and their implications in gut health, focusing on major gastrointestinal diseases including colorectal cancer, inflammatory bowel disease, and irritable bowel syndrome.

Level of intestinal permeability markers and selected aspects of diet and BMI of Polish e-sports players

BACKGROUND

The intestinal microbiota, also called visceral brain, exhibits high biological activity and influences health status. The aim of this study was to evaluate selected dietary determinants of the levels of intestinal permeability markers (zonulin and LPS endotoxin) in a group of e-sportsmen.

MATERIALS AND METHODS

The study was conducted among 174 male athletes (18-28 years old), training at the professional (n = 44) and semi-professional level (n = 130). The study included: weight and height measurements (Holtain anthropometer, Tanita TBF300), assessment of BMI, determination of zonulin and LPS levels in fecal samples (ELISA tests) and assessment of frequency of consumption of selected food groups (FFQ). Statistical analysis was performed using chi2 and Student's t tests and Spearman's rank correlation, at a significance level of p < 0.05.

RESULTS

The group was dominated by e-sportsmen with elevated levels of LPS endotoxin (66.67%), zonulin (85.74%) and normative BMI (59.70%), with no significant differences according to sports level. There was a positive correlation between BMI and levels of zonulin (R = 0.49; p < 0.001) and LPS (R = 0.24; p < 0.05). Zonulin levels also increased with more frequent consumption of sweet cereals (R = 0.21; p < 0.05), pork meats (R = 0.21; p < 0.05) and red meat dishes (R = 0.18; p < 0.05).

CONCLUSIONS

Excessive body weight and a poor health diet were shown to have a negative effect on increasing intestinal permeability, suggesting the rationale for monitoring and rationalizing diet and nutritional status to optimize the intestinal microbiota of e-sportsmen.

Maternal high-fat diet disrupts intestinal mucus barrier of offspring by regulating gut immune receptor LRRC19

Maternal high fat diet (MHFD) increased colitis susceptibility in adulthood. However, the mechanism remains unclear. We sought to explore whether novel gut immune receptor leucine-rich repeat C19 (LRRC19) contributed to the impaired mucus barrier of offspring exposed to MHFD via gut immune response and microbiota. The results showed that MHFD significantly impaired the intestinal mucus barrier of offspring, and up-regulated the expression of LRRC19. Lrrc19 deletion alleviated the mucus barrier disruption. Mechanistically, metagenome sequencing revealed that the MHFD-induced gut microbiota alteration was partly restored in Lrrc19-/- offspring. Muc2-associated bacteria were decreased in the MHFD group, such as Akkermansia_muciniphila_CAG_154, which increased in the Lrrc19-deficient offspring. Moreover, Lrrc19-/- offspring had a higher rate of indole-3-acetic acid (IAA)-producing bacterium, such as Lactobacillus reuteri. A targeted metabolomics analysis revealed that IAA emerged as the top candidate that might mediate the protective effects. IAA was found to improve the mucus barrier function by increasing the ratio of interleukin-22 (IL-22)+ ILC3 cells in an aryl hydrocarbon receptor (AhR)-dependent manner. These results suggest that MHFD disrupts the intestinal mucus barrier of offspring through regulating gut immune receptor LRRC19 and inducing an imbalance of gut microbiota and microbiota-derived metabolites.

Gut Microbiome and Bile Acid Interactions: Mechanistic Implications for Cholangiocarcinoma Development, Immune Resistance, and Therapy

Cholangiocarcinoma (CCA) is a rare but highly malignant carcinoma of bile duct epithelial cells with a poor prognosis. The major risk factors of CCA carcinogenesis and progression are cholestatic liver diseases. The key feature of primary sclerosing cholangitis and primary biliary cholangitis is chronic cholestasis. It indicates a slowdown of hepatocyte secretion of biliary lipids and metabolites into bile as well as a slowdown of enterohepatic circulation (bile acid recirculation) of bile acids with dysbiosis of the gut microbiome. This leads to enterohepatic recirculation and an increase of toxic secondary bile acids. Alterations of serum and liver bile acid compositions via the disturbed enterohepatic circulation of bile acids and the disturbance of the gut microbiome then activate a series of hepatic and cancer cell signaling pathways that promote CCA carcinogenesis and progression. This review focuses on the mechanistic roles of bile acids and the gut microbiome in the pathogenesis and progression of CCA. It also evaluates the therapeutic potential of targeting the gut microbiome and bile acid-mediated signaling pathways for the therapy and prophylaxis of CCA.

Ultrasound improves the digestibility of oxidized silver carp (Hypophthalmichthys molitrix) myofibrillar protein: Changes from structure to peptide release

The objective of this study was to investigate the effect of ultrasound on the digestibility of oxidized silver carp myofibrillar protein (MP). The MP solutions were oxidized with a hydroxyl radical generating system, and subsequently subjected to 100 W, 150 W, 200 W ultrasound treatment, respectively. The results showed that ultrasound effectively recovered the reduction in the digestibility of oxidized MP, especially the 150 W ultrasound achieved the best effect. The 150 W ultrasound reduced the particle size and turbidity of oxidized MP by 26.71 % and 35.49 %, respectively. The analysis of sulfhydryl, disulfide bonds, intrinsic fluorescence, and surface hydrophobicity suggested that ultrasound caused the breakage of disulfide bonds, which promoted the depolymerization oxidized MP. The morphology observed by atomic force microscope further evidenced that ultrasound reduced the degree of oxidized MP aggregation. The results of peptidomics showed that ultrasound treatment largely increased the peptide release of oxidized MP during the gastrointestinal digestion, especially the peptide containing lysine and arginine. Take together, ultrasound promoted the break of disulfide bond, which led to the depolymerization of oxidized MP and thus improved the digestibility of oxidized MP.

Obesity and the gut microbiota: implications of neuroendocrine and immune signaling

Obesity is a major health challenge due to its high prevalence and associated comorbidities. The excessive intake of a diet rich in fat and sugars leads to a persistent imbalance between energy intake and energy expenditure, which increases adiposity. Here, we provide an update on relevant diet-microbe-host interactions contributing to or protecting from obesity. In particular, we focus on how unhealthy diets shape the gut microbiota and thus impact crucial intestinal neuroendocrine and immune system functions. We describe how these interactions promote dysfunction in gut-to-brain neuroendocrine pathways involved in food intake control and postprandial metabolism and elevate the intestinal proinflammatory tone, promoting obesity and metabolic complications. In addition, we provide examples of how this knowledge may inspire microbiome-based interventions, such as fecal microbiota transplants, probiotics, and biotherapeutics, to effectively combat obesity-related disorders. We also discuss the current limitations and gaps in knowledge of gut microbiota research in obesity.

Gut microbial metabolites: The bridge connecting diet and atherosclerosis, and next-generation targets for dietary interventions

Mounting evidence indicates that gut microbial metabolites are central hubs linking the gut microbiota to atherosclerosis (AS). Gut microbiota enriched with pathobiont bacteria responsible for producing metabolites like trimethylamine N-oxide and phenylacetylglutamine are related to an increased risk of cardiovascular events. Furthermore, gut microbiota enriched with bacteria responsible for producing short-chain fatty acids, indole, and its derivatives, such as indole-3-propionic acid, have demonstrated AS-protective effects. This study described AS-related gut microbial composition and how microbial metabolites affect AS. Summary findings revealed gut microbiota and their metabolites-targeted diets could benefit AS treatment. In conclusion, dietary interventions centered on the gut microbiota represent a promising strategy for AS treatment, and understanding diet-microbiota interactions could potentially be devoted to developing novel anti-AS therapies.

Efficacy Evaluation of Selenium-enriched Akkermansia muciniphila in the Treatment of Colon Tumor Mice

Selenium (Se)-enriched probiotics possess a variety of beneficial properties and are widely used in specialty foods and biomedical applications. Akkermansia muciniphila (AM) is being considered a promising candidate for the "next generation probiotics (NGPs)," which play an essential role in the field of tumor therapy. However, there are no studies on the efficacy of Se-enriched A. muciniphila (Se-AM) in the field of tumor therapy. The present study utilized inorganic Se bio-enrichment for the preparation of Se-AM. To evaluate the killing effect of Se-AM on CT26 cells, the actual efficacy and safety of Se-AM were investigated in a mouse model of colon cancer. The results showed that the Se-AM-cell lysate was able to significantly kill CT26 cells, but this killing effect was progressively weakened with decreasing concentrations of Se-AM-cell lysate. The results of animal experiments showed that Se-AM was able to safely and effectively curb the disease course of mice with colon tumors, reduce the tumor volume, lower the levels of IL-1β and IL-6, and increase the levels of TNF-α in the colon of mice. Furthermore, treatment with Se-AM in mice led to a restoration of gut microbiota diversity, reaching levels similar to those observed in healthy controls. This restoration was accompanied by a significant enrichment of beneficial genera, such as Turicibacter, Butyricimonas, Prevotella, and Akkermansia. In summary, Se-AM prepared in this study was able to produce effective killing of CT26 cells directly and played a substantial therapeutic role in a mouse model of colon tumors constructed from CT26 cells. Se-AM had no adverse effect on the heart, liver, spleen, lungs, and kidney of mice and demonstrated a high level of safety. Meanwhile, Se-AM significantly raised the level of the Shannon index and the ratio of Firmicutes to Bacteroidetes of the gut microbiota in mice, indicating its ability to regulate the homeostasis of the microbiota. These results imply that Se-AM has great application value in the field of colon cancer treatment.

Emerging insights into the gut microbiota as a key regulator of immunity and response to immunotherapy in hepatocellular carcinoma

The gut microbiota, a complex microbial ecosystem closely connected to the liver via the portal vein, has emerged as a critical regulator of liver health and disease. Numerous studies have underscored its role in the onset and progression of liver disorders, including alcoholic liver disease, metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction-associated steatohepatitis (MASH), liver fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). This review provides a comprehensive overview of current insights into the influence of the gut microbiota on HCC progression, particularly its effects on immune cells within the HCC tumor microenvironment (TME). Furthermore, we explore the potential of gut microbiota-targeted interventions, such as antibiotics, probiotics, prebiotics, and fecal microbiota transplantation (FMT), to modulate the immune response and improve outcomes of immunotherapy in HCC. By synthesizing insights from recent studies, this review aims to highlight microbiota-based strategies that may enhance immunotherapy outcomes, advancing personalized approaches in HCC treatment.

"Food Is Medicine" Strategies for Respiratory Health: Evidence From NHANES 2005-2012

OBJECTIVE

Compared with other diseases with similar global burdens, little is known about how lifestyle factors other than smoking affect respiratory health, and few studies have systematically investigated the combined associations between diet and respiratory health. The aim of this research was to examine the Dietary Inflammation Index (DII), Healthy Eating Index (HEI)-2015, and individual food and nutrient associations with multiple respiratory outcomes.

METHODS

This study combined a cross-sectional study with a prospective cohort study to systematically evaluate data from adults aged 40 years or older (N = 13,227) from 4 National Health and Nutrition Examination Survey cycles (2005-2006 through 2011-2012) with lung function measures in a subset (n = 6337). DII, HEI-2015, and individual foods and nutrients were evaluated for their associations with respiratory symptoms (cough, phlegm problem, wheezing, and exertional dyspnea), chronic lung disease (asthma, chronic bronchitis, and emphysema), lung function (percentage of predicted forced expiratory volume in 1 second [FEV1pp], percentage of predicted forced vital capacity [FVCpp], forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC), obstructive or restrictive spirometry patterns), respiratory cancer, all-cause mortality, and respiratory disease mortality.

RESULTS

For each point increase in DII, the odds of cough (adjusted odds ratio [aOR], 1.036; 95% CI, 1.002-1.071), wheezing (aOR, 1.044; 95% CI, 1.013-1.075), exertional dyspnea (aOR, 1.042; 95% CI, 1.019-1.066), emphysema (aOR, 1.096; 95% CI, 1.030-1.166), and restrictive spirometry patterns (aOR, 1.066; 95% CI, 1.007-1.128) increased and FEV1pp (adjusted mean difference [aMD], -0.525%; 95% CI, -0.747% to -0.303%) and FVCpp (aMD, -0.566%; 95% CI, -0.762% to -0.371%) decreased. HEI-2015 scores were similarly associated with these respiratory outcomes. Each point increase in the DII was associated with an increased risk of all-cause mortality (adjusted hazard ratio [aHR], 1.048; 95% CI, 1.025-1.071) and respiratory disease mortality (aHR, 1.097; 95% CI, 1.013-1.189); each increase in the HEI-2015 score was associated with a decreased risk of all-cause mortality (aHR, 0.994; 95% CI, 0.991-0.997). The multiple adequacy components recommended in the HEI (fruits, vegetables, whole grains, seafood and plant proteins, and monounsaturated fatty acids) were associated with better respiratory outcomes; the moderation components of restricting refined grains, sugars, and saturated fats were associated with better respiratory outcomes, but restricting sodium intake was associated with increased respiratory symptoms.

CONCLUSIONS

The results of this study suggest that a low-inflammatory diet and a healthy diet are consistently associated with better respiratory outcomes. These findings support the potential benefits of a "Food Is Medicine" strategy for respiratory health.

The causal relationship between the gut microbiota and endometrial cancer: a mendelian randomization study

BACKGROUND

Gut microbiota is associated with endometrial cancer (EC); however, the causal relationship remains unexplored. This study attempted to explore the relationship between gut microbiota and EC using Mendelian randomization (MR) methods.

METHODS

In this two-sample MR analysis, we used MiBioGen's gut microbiota data as the exposure and three datasets from European populations with EC as the outcome. The EC datasets included general EC, endometrioid histology, and non-endometrioid histology. Single nucleotide polymorphism (SNP) was used as the instrumental variable. Inverse variance weighted (IVW), multiplicative random effects IVW (MRE-IVW), Maximum likelihood (ML), MR Egger, MR-PRESSO, and the weighted median were used to perform MR analysis. Sensitivity analysis was conducted to assess the reliability of the results.

RESULTS

In this MR analysis of three EC datasets, specific gut microbiota were identified as potentially associated with different pathological types of EC. For general EC (ID: ebi-a-GCST006464), Family.Acidaminococcaceae (OR = 1.23, 95%CI: 1.02-1.48) and genus.Butyrivibrio (OR = 1.08, 95%CI: 1.01-1.16) were identified as risk factors, while genus.Ruminococcaceae UCG014 (OR = 0.82, 95%CI: 0.69-0.98) and genus.Turicibacter (OR = 0.84, 95%CI: 0.73-0.97) appeared to have protective effects. For endometrioid histology EC (ID: ebi-a-GCST006465), Family.Acidaminococcaceae (OR = 1.27, 95%CI: 1.01-1.59) and genus.Butyrivibrio (OR = 1.10, 95%CI: 1.01-1.19) were identified as risk factors, while several microbiota, including Family.Lactobacillaceae, genus.Coprococcus3, genus.Dorea, genus.Flavonifractor, genus.Lactobacillus, genus.Paraprevotella, and genus.Turicibacter, were identified as protective factors. For non-endometrioid histology EC (ID: ebi-a-GCST006466), Family.Rhodospirillaceae (OR = 1.41, 95%CI: 1.01-1.96) and genus.Peptococcus (OR = 1.43, 95%CI: 1.07-1.91) were identified as risk factors, while no significant protective factors were identified.

CONCLUSIONS

This two-sample MR study has identified gut microbiota with potential causal relationships with EC, varying by pathological type. These findings provide new insights into the pathogenesis of EC and suggest directions for future research on diagnosis and treatment strategies.

Senile Osteoarthritis Regulated by the Gut Microbiota: From Mechanisms to Treatments

Osteoarthritis (OA) is a chronic, progressive degenerative joint disease that affects the entire synovial joint, leading to the progressive degeneration of articular cartilage. It seriously affects the quality of life and global disability of patients. OA is affected by a variety of factors; the most significant risk factor for OA is age. As individuals age, the risk and severity of OA increase due to the exacerbation of cartilage degeneration and wear and tear. In recent years, research has indicated that the gut microbiota may play a significant role in the aging and OA processes. It is anticipated that regulating the gut microbiota may offer novel approaches to the treatment of OA. The objective of this paper is to examine the relationship between the gut microbiota and senile OA, to investigate the potential mechanisms involved. This review also summarizes the therapeutic strategies related to gut flora in OA management, such as prebiotics and probiotics, diet, exercise, traditional Chinese medicine (TCM) modification, and fecal microbiota transplantation (FMT), highlighting the potential clinical value of gut flora and elucidating the current challenges. The foundation for future research directions is established through the summarization of current research progress.

Perspectives on Diet and Exercise Interaction for Healthy Aging: Opportunities to Reduce Malnutrition Risk and Optimize Fitness

Nutrition and exercise play a pivotal role in counteracting the effects of aging, promoting health, and improving physical fitness in older adults. This perspective study examines their interplay, highlighting their combined potential to preserve muscle mass, cognitive function, and quality of life. The objective is to address gaps in the current understanding, such as the frequent neglect of dietary intake in exercise interventions and vice versa, which can limit their effectiveness. Through a synthesis of the existing literature, we identify key findings, emphasizing the importance of adequate nutritional intake-particularly protein, essential amino acids, and micronutrients-in supporting exercise benefits and preventing sarcopenia and malnutrition. Additionally, supplementation strategies, such as omega-3 fatty acids, creatine, and essential amino acids, are explored alongside the emerging role of the gut microbiota in mediating the benefits of nutrition and exercise. Despite these advances, challenges remain, including determining optimal dosages and timing and addressing individual variability in responses. Personalized approaches tailored to sex differences, gut microbiota diversity, and baseline health conditions are critical for maximizing intervention outcomes. Our conclusions underscore the necessity of integrated strategies that align dietary and exercise interventions to support healthy and active aging. By addressing these gaps, future research can provide actionable insights to optimize health and quality of life in older populations.

Unlocking Gut Health: The Potent Role of Stilbenoids in Intestinal Homeostasis

Stilbenoids are a class of naturally occurring phenolic compounds found in various plant species, characterized by a stilbene backbone with diverse substituents that confer a range of biological activities. These compounds exhibit antioxidant, anti-inflammatory, and antimicrobial properties, making them promising candidates for improving intestinal health. The intestinal tract plays a critical role in nutrient digestion, absorption, and immune defense, and maintaining its integrity is vital for animal growth. Stilbenoids contribute to gut health by enhancing intestinal morphology, supporting mucosal immune responses, regulating gut microbiota composition, modulating metabolic pathways, and maintaining mitochondrial health. This review provides a comprehensive analysis of key stilbenoids, including resveratrol, pterostilbene, piceatannol, and oxyresveratrol, focusing on their biological effects and regulatory mechanisms. By highlighting their roles in mitigating intestinal inflammation and promoting gut function, this review provides a basis for the practical application of stilbenoids in animal health and husbandry.

Targeted microbiota dysbiosis repair: An important approach to health management after spinal cord injury

Current research primarily focuses on the pathological mechanisms of spinal cord injury (SCI), seeking to promote spinal cord repair and restore motorial and sensory functions by elucidating mechanisms of cell death or axonal regeneration. However, SCI is almost irreversible, and patients often struggle to regain mobility or self-care abilities after injuries. Consequently, there has been significant interest in modulating systemic symptoms following SCI to improve patients' quality of life. Neuron axonal disconnection and substantial apoptotic events following SCI result in signal transmission loss, profoundly impacting various organ and systems, including the gastrointestinal tract. Dysbiosis can lead to severe bowel dysfunction in patients, substantially lowering their quality of life and significantly reducing life expectancy of them. Therefore, researches focusing on the restoration of the gut microbiota hold promise for potential therapeutic strategies aimed at rehabilitation after SCI. In this paper, we explore the regulatory roles that dietary fiber, short-chain fatty acids (SCFAs), probiotics, and microbiota transplantation play in patients with SCI, summarize the potential mechanisms of post-SCI dysbiosis, and discuss possible strategies to enhance long-term survival of SCI patients. We aim to provide potential insights for future research aimed at ameliorating dysbiosis in SCI patients.

Leaky Gut Syndrome: An Interplay Between Nutrients and Dysbiosis

PURPOSE OF REVIEW

The gut microbiota (GM) is directly related to health and disease. In this context, disturbances resulting from excessive stress, unbalanced diet, alcohol abuse, and antibiotic use, among other factors, can contribute to microbiota imbalance, with significant impacts on host health. This review provides a comprehensive examination of the literature on the influence of diet on dysbiosis and increased intestinal permeability over the past five years.

RECENT FINDINGS

Diet can be considered one of the main modulating factors of GM, impacting its composition and functionality. Excessive consumption of simple carbohydrates, saturated fats, and processed foods appears to be directly linked to dysbiosis, which can lead to intestinal hyperpermeability and leaky gut syndrome. On the other hand, diets primarily composed of food groups such as nuts, vegetables, fruits, fish, and poultry in moderate quantities, along with limited consumption of red and processed meats, are associated with a more diverse, healthier, and beneficial GM for the host. It is worth noticing that the use of prebiotics and probiotics, omega-3 supplementation, polyunsaturated fatty acids, and vitamins A, B, C, D, and E can positively modulate the intestinal microbiota by altering its metabolic activity, microbial composition, and improve intestinal barrier function. This review points to a new perspective regarding individualized dietary intervention and the need to integrate it into several aspects of cellular biology, biochemistry, and microbiology to prescribe more effective diets and thus contribute to patients' comprehensive health.

Novel Fermented Plant-Based Functional Beverage: Biological Potential and Impact on the Human Gut Microbiota

Controlled fermentation carried out by selected starters might enhance the safety, nutritional, and biological profiles of non-dairy fermented products. This research aims to study the biological potential and impact on the human gut microbiota of a novel fermented finger millet-based product. Finger millet (Eleusine coracana), suspended in an aqueous sucrose-based solution, was fermented by Weissella confusa 2LABPT05 and Lactiplantibacillus plantarum 299v (1%, 1:1 ratio (v/v)), at 30 °C/200 rpm in an orbital incubator until pH ≈ 4.5-5.0. Microbial growth, phenolic compounds, antioxidant, and antidiabetic activities were evaluated. In vitro digestion followed by in vitro faecal fermentation were used to study the impact of the fermented plant-based functional beverage (PBFB) on the human gut microbiota. Antidiabetic activity (21% vs. 14%) and total phenolics (244 vs. 181 mg of gallic acid equivalents/kg PBFB) increased with fermentation. The digested fermented PBFB contributed to the increase, over the first 6 h, of the Bifidobacterium's 16S rRNA gene copy numbers, concomitant with significant release of the acetic, propionic, and butyric short chain fatty acids, and also lactic acid. The novel PBFB has been shown to have antidiabetic potential and bifidogenic effects, and consequently its consumption might positively impact blood glucose levels and the human gut microbiota.

Gut Microbiota-Bone Axis

BACKGROUND

Knowledge of the complex interplay between gut microbiota and human health is gradually increasing as it has just recently been a field of such great interest.

SUMMARY

Recent studies have reported that communities of microorganisms inhabiting the gut influence the immune system through cellular responses and shape many physiological and pathophysiological aspects of the body, including muscle and bone metabolism (formation and resorption). Specifically, the gut microbiota affects skeletal homeostasis through changes in host metabolism, the immune system, hormone secretion, and the gut-brain axis. The major role on gut-bone axis is due to short-chain fatty acids (SCFAs). They have the ability to influence regulatory T-cell (Tregs) development and activate bone metabolism through the action of Wnt10. SCFA production may be a mechanism by which the microbial community, by increasing the serum level of insulin-like growth factor 1 (IGF-1), leads to the growth and regulation of bone homeostasis. A specific SCFA, butyrate, diffuses into the bone marrow where it expands Tregs. The Tregs induce production of the Wnt ligand Wnt10b by CD8+ T cells, leading to activation of Wnt signaling and stimulation of bone formation. At the hormonal level, the effect of the gut microbiota on bone homeostasis is expressed through the biphasic action of serotonin. Some microbiota, such as spore-forming microbes, regulate the level of serotonin in the gut, serum, and feces. Another group of bacterial species (Lactococcus, Mucispirillum, Lactobacillus, and Bifidobacterium) can increase the level of peripheral/vascular leptin, which in turn manages bone homeostasis through the action of brain serotonin.

Effects of ultra-processed foods on the liver: insights from gut microbiome and metabolomics studies in rats

Purpose

High consumption of Ultra-processed foods (UPF) have been identified as a potential risk factor for Non-alcoholic fatty liver disease (NAFLD). Nevertheless, there is limited empirical evidence regarding the impact of UPF, which are typical combination of processed foods, on liver health through alterations in gut microbiota and metabolic processes. We aim to examine the potential impact of UPF on liver health and to explore the role of gut microbiota and metabolites.

Methods

This study used Sprague-Dawley rats to mimic modern UPF diets for 90 days. Some serum biochemical indices, inflammatory factors, oxidative stress markers, hematoxylin-eosin (HE) staining of the liver, 16S ribosomal RNA (rRNA) and Liquid chromatography-mass spectrometry (LC-MS) of rat feces were detected.

Results

The UPF diet-induced simple steatosis of the liver in rats without affecting the levels of IL-6, GSH, MDA, and SOD. Additionally, it modified the gut microbiota, increasing potentially harmful bacteria, such as norank_f__Desulfovibrionaceae and Staphylococcus, while also elevating the relative abundance of potentially beneficial bacteria, including Dubosiella and Allobaculum. Furthermore, the consumption of UPF led to a metabolomic disorder characterized by disruptions in the sphingolipid signaling pathway, sulfur relay system, and arachidonic acid metabolism.

Conclusion

In conclusion, the findings of this study indicate that the consumption of UPF influences the development of simple hepatic steatosis, potentially through alterations in gut microbiota and metabolomics.

The impact of fibre and prebiotic interventions on outcomes in cancer and haematopoietic stem cell transplantation: A systematic review

BACKGROUND & AIMS

Cancer therapy is associated with a range of toxicities that severely impact patient well-being and a range of clinical outcomes. Dietary fibre/prebiotics characteristically improve the gastrointestinal microenvironment, which consequently elicits beneficial downstream effects that could be relevant to the prevention and management of treatment-related toxicities. Despite the compelling theoretical scientific rationale there has been limited effort to synthesise the available evidence to conclude such scientific underpinning to the clinical use of fibre/prebiotics in cancer patients. Therefore, this systematic review aimed to evaluate the clinical impact of fibre/prebiotic-based interventions on gastrointestinal-side effects; gastrointestinal-microbiome; clinical outcomes; nutrition status and body composition; and quality-of-life in children and adults being treated for cancer or undergoing a haematopoietic stem cell transplant (HSCT).

METHODS

This study was conducted in adherence to PRISMA guidelines, and the protocol was published prospectively with PROSPERO (CRD42022299428). Three databases (MEDLINE (Ovid), CINHAL, EMBASE) were searched from inception to December 2023. All articles were assessed for bias using the Cochrane risk-of-bias tool RoB 2.0 (for RCTs) and ROBINS-I (for non-RCTs).

RESULTS

A total of 9989 de-duplicated records were identified, of these, 14 (paediatrics [n = 1], adults [n = 13]) met the inclusion criteria (randomised controlled trials (RCT) [n = 11], observational or non-RCTs [n = 3]). The risk-of-bias was graded to be serious/high (n = 6); moderate/some concerns (n = 7); low (n = 1). Interventions included prebiotic supplement (n = 8), nutrition supplement/formula with added fibre/prebiotic (n = 3) and dietary modification (n = 3). The dose of fibre intervention ranged from 2.4g to 30g per day. Substantial heterogeneity of target parameters was identified across a range all outcome categories, precluding definitive conclusions.

CONCLUSION

The scientific rationale for fibre/prebiotics-based interventions for the prevention or management of cancer treatment-related toxicities is compelling. However, it is clear that the scientific and clinical field remains disconnected in how to effectively translate this approach to improve cancer outcomes. High-quality intervention studies translatable to clinical practice are now evidently crucial to determine if and how fibre/prebiotics should be used to support people undergoing cancer or HSCT therapy.

Understanding the complex function of gut microbiota: its impact on the pathogenesis of obesity and beyond: a comprehensive review

Obesity is a multifactorial condition influenced by genetic, environmental, and microbiome-related factors. The gut microbiome plays a vital role in maintaining intestinal health, increasing mucus creation, helping the intestinal epithelium mend, and regulating short-chain fatty acid (SCFA) production. These tasks are vital for managing metabolism and maintaining energy balance. Dysbiosis-an imbalance in the microbiome-leads to increased appetite and the rise of metabolic disorders, both fuel obesity and its issues. Furthermore, childhood obesity connects with unique shifts in gut microbiota makeup. For instance, there is a surge in pro-inflammatory bacteria compared to children who are not obese. Considering the intricate nature and variety of the gut microbiota, additional investigations are necessary to clarify its exact involvement in the beginnings and advancement of obesity and related metabolic dilemmas. Currently, therapeutic methods like probiotics, prebiotics, synbiotics, fecal microbiota transplantation (FMT), dietary interventions like Mediterranean and ketogenic diets, and physical activity show potential in adjusting the gut microbiome to fight obesity and aid weight loss. Furthermore, the review underscores the integration of microbial metabolites with pharmacological agents such as orlistat and semaglutide in restoring microbial homeostasis. However, more clinical tests are essential to refine the doses, frequency, and lasting effectiveness of these treatments. This narrative overview compiles the existing knowledge on the multifaceted role of gut microbiota in obesity and much more, showcasing possible treatment strategies for addressing these health challenges.

Enzymatic Regulation of the Gut Microbiota: Mechanisms and Implications for Host Health

The gut microbiota, a complex ecosystem, is vital to host health as it aids digestion, modulates the immune system, influences metabolism, and interacts with the brain-gut axis. Various factors influence the composition of this microbiota. Enzymes, as essential catalysts, actively participate in biochemical reactions that have an impact on the gut microbial community, affecting both the microorganisms and the gut environment. Enzymes play an important role in the regulation of the intestinal microbiota, but the interactions between enzymes and microbial communities, as well as the precise mechanisms of enzymes, remain a challenge in scientific research. Enzymes serve both traditional nutritional functions, such as the breakdown of complex substrates into absorbable small molecules, and non-nutritional roles, which encompass antibacterial function, immunomodulation, intestinal health maintenance, and stress reduction, among others. This study categorizes enzymes according to their source and explores the mechanistic principles by which enzymes drive gut microbial activity, including the promotion of microbial proliferation, the direct elimination of harmful microbes, the modulation of bacterial interaction networks, and the reduction in immune stress. A systematic understanding of enzymes in regulating the gut microbiota and the study of their associated molecular mechanisms will facilitate the application of enzymes to precisely regulate the gut microbiota in the future and suggest new therapeutic strategies and dietary recommendations. In conclusion, this review provides a comprehensive overview of the role of enzymes in modulating the gut microbiota. It explores the underlying molecular and cellular mechanisms and discusses the potential applications of enzyme-mediated microbiota regulation for host gut health.

In Vitro Evaluation of Probiotic Activities and Anti-Obesity Effects of Enterococcus faecalis EF-1 in Mice Fed a High-Fat Diet

This research sought to assess the anti-obesity potential of Enterococcus faecalis EF-1. An extensive and robust in vitro methodology confirmed EF-1's significant potential in combating obesity, probably due to its excellent gastrointestinal tract adaptability, cholesterol-lowering property, bile salt hydrolase activity, α-glucosidase inhibition, and fatty acid absorption ability. Moreover, EF-1 exhibited antimicrobial activity against several pathogenic strains, lacked hemolytic activity, and was sensitive to all antibiotics tested. To further investigate EF-1's anti-obesity properties in vivo, a high-fat diet (HFD) was used to induce obesity in C57BL/6J mice. Treatment with EF-1 (2 × 109 CFU/day) mitigated HFD-induced body weight gain, reduced adipose tissue weight, and preserved liver function. EF-1 also ameliorated obesity-associated microbiota imbalances, such as decreasing the Firmicutes/Bacteroidetes ratio and boosting the levels of bacteria (Faecalibacterium, Mucispirillum, Desulfovibrio, Bacteroides, and Lachnospiraceae_NK4A136_group), which are responsible for the generation of short-chain fatty acids (SCFAs). Concurrently, the levels of total SCFAs were elevated. Thus, following comprehensive safety and efficacy assessments in vitro and in vivo, our results demonstrate that E. faecalis EF-1 inhibits HFD-induced obesity through the regulation of gut microbiota and enhancing SCFA production. This strain appears to be a highly promising candidate for anti-obesity therapeutics or functional foods.

Different artificial feeding strategies shape the diverse gut microbial communities and functions with the potential risk of pathogen transmission to captive Asian small-clawed otters (Aonyx cinereus)

Captive otters raised in zoos are fed different artificial diets, which may shape gut microbiota. The objective is to evaluate the impacts of two different artificial diets on microbial communities and function capabilities and short-chain fatty acid (SCFA) profiles in healthy otters' feces. A total of 16 Asian small-clawed otters in two groups (n = 8) were selected. Group A otters were fed raw loaches supplemented with commercial cat food (LSCF) diet, and group B otters were fed raw crucian diet. The communities and functional capabilities of microbiota in feces were assessed with metagenomic sequencing. Captive otters fed two kinds of diets possessed different gut microbial communities and functional capabilities. Various pathogenic bacteria, like Escherichia coli and Clostridium perfringens, were enriched in the samples from the two groups, respectively. Most of the differential pathways of nutrient metabolism were significantly enriched in group A, and the distributions of carbohydrate enzymes in the two groups significantly differed from each other. Multiple resistance genes markedly accumulated in fecal samples of the group A otters with LSCF diet. Higher concentrations of SCFAs were also observed in group A otters. Two feeding strategies were both likely to facilitate the colonization and expansion of various pathogenic bacteria and the accumulation of resistance genes in the intestines of captive otters, suggesting that risk of pathogen transmission existed in the current feeding process. Commercial cat food could supplement various nutrients and provide a substrate for the production of SCFAs, which might be beneficial for the otters' intestinal fermentation and metabolism.

IMPORTANCE

Captive otters fed with different diets possessed distinct gut microbial communities and functions, with the enrichment of several pathogens and multiple resistance genes in their gut microbiota. The current artificial feeding strategies had the possibility to accelerate the colonization and proliferation of various pathogenic bacteria in the intestines of otters and the spread of resistance genes, increasing the risk of diseases. In addition, supplementation with commercial cat food had benefits for otters' intestinal fermentation and the metabolism of gut microbiota.

Gut Microbiota: Association with Fiber Intake, Ultra-Processed Food Consumption, Sex, Body Mass Index, and Socioeconomic Status in Medical Students

The gut microbiota plays a vital role in various physical and physiological processes, including immune system regulation, neurotransmitter production, inflammatory response modulation, and the inhibition of pathogenic organisms. An imbalance in the microbial community, known as dysbiosis, has been associated with numerous health issues. Biological influences, health behaviors, socioeconomic determinants, and nutritional status can disrupt this balance.

OBJECTIVE

To evaluate the differences in the gut microbiota composition in medical students according to fiber intake, ultra-processed food (UPF) consumption, sex, body mass index, and socioeconomic status.

METHODS

A cross-sectional study was conducted with 91 medical students, and 82 fecal samples were analyzed. Sociodemographic and dietary data were collected via questionnaires, UPF consumption was assessed using the NOVA classification, and trained nutritionists performed anthropometry. DNA extraction and 16S rRNA sequencing were performed for the microbial analysis. Bioinformatics and statistical tests included the Dunn and Kruskal-Wallis tests, a PCoA analysis, PERMANOVA, ANOVA, Spearman's rank correlation, and alpha and beta diversity metrics.

RESULTS

Dietary fiber intake strongly influences gut microbiota composition. Lower fiber intake was associated with a higher prevalence of Parabacteroides and Muribaculaceae. Prevotella was more prevalent in individuals with lower UPF intake, while Phascolarctobacterium was prevalent in those with higher UPF consumption. Significant differences were associated with sex and UPF consumption but not BMI or SES. Women consumed more UPF, which correlated with distinct gut microbiota profiles.

CONCLUSIONS

This study highlights the significant impact of diet, particularly fiber intake and UPF, on gut microbiota composition, emphasizing the importance of dietary habits in maintaining gut health.

Dietary legumes and gut microbiome: a comprehensive review

The gut microbiome plays a crucial role in human health, affecting metabolic, immune, and cognitive functions. While the impact of various dietary components on the microbiome is well-studied, the effect of legumes remains less explored. This review examines the influence of legume consumption on gut microbiome composition, diversity, and metabolite production, based on 10 human and 21 animal studies. Human studies showed mixed results, with some showing increased microbial diversity and others finding no significant changes. However, legume consumption was linked to increases in beneficial bacteria like Bifidobacterium and Faecalibacterium. Animal studies generally indicated enhanced microbial diversity and composition changes, though these varied by legume type and the host's health. Some studies highlighted legume-induced shifts in bacteria associated with better metabolic health. Overall, the review emphasizes the complexity of legume-microbiome interactions and the need for standardized methodologies and longitudinal studies. While legumes have the potential to positively affect the gut microbiome, the effects are nuanced and depend on context. Future research should investigate the long-term impacts of legume consumption on microbiome stability and its broader health implications, particularly for disease prevention and dietary strategies.

Moderate-intensity continuous training and high-intensity interval training alleviate glycolipid metabolism through modulation of gut microbiota and their metabolite SCFAs in diabetic rats

Glucose and lipid metabolism disorders are typical of diabetic patients and are important factors leading to macrovascular and microvascular complications. The aim of this study was to understand the effects of different exercises on glycolipid metabolism in diabetic rats and the role of gut flora in metabolic maintenance. We measured glycolipid metabolic indices and short-chain fatty acids (SCFAs) content and sequenced and analyzed gut microbes after 8 weeks of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) programs in type 2 diabetic rats(T2DM). We found that Enterococcaceae, Enterococcus, Subdoligranulum, Kurthia, Bacillales, and Planococcaceae may be key bacterial taxa related to T2DM and that both programs of exercise regulated the intestinal flora of rats with T2DM, improved their glycolipid metabolism, increased the abundance of SCFA-producing intestinal bacteria, and it was found that the PWY-5676 and P163-PWY pathways which are closely related to production of SCFAs were significantly upregulated in the exercise groups. Notably, MICT appeared to be more effective than HIIT in increasing the homogeneity of rat intestinal flora, enriching species, and increasing acetic acid and butyric acid content. These results suggest that exercise improves glycolipid metabolism in diabetic rats, which may be attributed to alterations in the structure of their intestinal flora.

Gut Microbiota and Derived Metabolites Mediate Obstructive Sleep Apnea Induced Atherosclerosis

Background

Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia/hypercapnia (IHC), affects predominantly obese individuals, and increases atherosclerosis risk. Since we and others have implicated gut microbiota and metabolites in atherogenesis, we dissected their contributions to OSA-induced atherosclerosis.

Results

Atherosclerotic lesions were compared between conventionally-reared specific pathogen free (SPF) and germ-free (GF) ApoE -/- mice following a high fat high cholesterol diet (HFHC), with and without IHC conditions. The fecal microbiota and metabolome were profiled using 16S rRNA gene amplicon sequencing and untargeted tandem mass spectrometry (LC-MS/MS) respectively. Phenotypic data showed that HFHC significantly increased atherosclerosis as compared to regular chow (RC) in both aorta and pulmonary artery (PA) of SPF mice. IHC exacerbated lesions in addition to HFHC. Differential abundance analysis of gut microbiota identified an enrichment of Akkermansiaceae and a depletion of Muribaculaceae (formerly S24-7) family members in the HFHC-IHC group. LC-MS/MS showed a dysregulation of bile acid profiles with taurocholic acid, taurodeoxycholic acid, and 12-ketodeoxycholic acid enriched in the HFHC-IHC group, long-chain N-acyl amides, and phosphatidylcholines. Interestingly, GF ApoE -/- mice markedly reduced atherosclerotic formation relative to SPF ApoE -/- mice in the aorta under HFHC/IHC conditions. In contrast, microbial colonization did not show a significant impact on the atherosclerotic progression in PA.

Conclusions

In summary, this research demonstrated that (1) IHC acts cooperatively with HFHC to induce atherosclerosis; (2) gut microbiota modulate atherogenesis, induced by HFHC/IHC, in the aorta not in PA; (3) different analytical methods suggest that a specific imbalance between Akkermansiaceae and Muribaculaceae bacterial families mediate OSA-induced atherosclerosis; and (4) derived bile acids, such as deoxycholic acid and lithocholic acid, regulate atherosclerosis in OSA. The knowledge obtained provides novel insights into the potential therapeutic approaches to prevent and treat OSA-induced atherosclerosis.

Changes in social environment impact primate gut microbiota composition

BACKGROUND

The gut microbiota (GM) has proven to be essential for both physical health and mental wellbeing, yet the forces that ultimately shape its composition remain opaque. One critical force known to affect the GM is the social environment. Prior work in humans and free-ranging non-human primates has shown that cohabitation and frequent social interaction can lead to changes in GM composition. However, it is difficult to assess the direction of causation in these studies, and interpretations are complicated by the influence of uncontrolled but correlated factors, such as shared diet.

RESULTS

We performed a 15-month longitudinal investigation wherein we disentangled the impacts of diet and social living conditions on GM composition in a captive cohort of 13 male cynomolgus macaques. The animals were in single housing for the first 3 months of the study initially with a variable diet. After baseline data collection they were placed on a controlled diet for the remainder of the study. Following this diet shift the animals were moved to paired housing for 6 months, enabling enhanced social interaction, and then subsequently returned to single housing at the end of our study. This structured sequencing of diet and housing changes allowed us to assess their distinct impacts on GM composition. We found that the early dietary adjustments led to GM changes in both alpha and beta diversity, whereas changes in social living conditions only altered beta diversity. With respect to the latter, we found that two particular bacterial families - Lactobacillaceae and Clostridiaceae - demonstrated significant shifts in abundance during the transition from single housing to paired housing, which was distinct from the shifts we observed based on a change in diet. Conversely, we found that other bacteria previously associated with sociality were not altered based on changes in social living conditions but rather only by changes in diet.

CONCLUSIONS

Together, these findings decouple the influences that diet and social living have on GM composition and reconcile previous observations in the human and animal literatures. Moreover, the results indicate biological alterations of the gut that may, in part, mediate the relationship between sociality and wellbeing.

Gut Microbiome-Host Genetics Co-Evolution Shapes Adiposity by Modulating Energy and Lipid Metabolism in Selectively Bred Broiler Chickens

Optimizing fat deposition is crucial for improving chicken production and meat quality. This study investigated the interactive roles of host genetics and gut microbiome in regulating abdominal fat deposition in selectively bred broiler chicken lines. We compared the gut microbiome composition and host whole-genome profiles between fat-line and lean-line broiler chickens that had been selectively bred for divergent abdominal fat levels over 15 generations. Despite identical dietary and environmental conditions, the two chicken lines exhibited significant differences in their gut microbiota. Lean-line broiler chickens exhibited an increased abundance of intestinal Lactobacillus and a decreased presence of potentially pathogenic species, such as Campylobacter coli, Corynebacterium casei, and Enterococcus faecalis. These microbial alterations were accompanied by shifts in the functional metagenome, with enrichment in pathways involved in energy metabolism and nutrient utilization in the lean-line chickens. Notably, the selective breeding process also led to genomic variations in the lean broilers, with single nucleotide polymorphisms predominantly observed in genes related to energy and lipid metabolism. Our findings suggest that the host-microbiome interactions play a key role in the divergent abdominal fat deposition phenotypes observed in these selectively bred chicken lines. The co-evolution of the gut microbiome and host genetics highlights the importance of considering both factors to optimize poultry production efficiency and meat quality. This study offers new insights into the intricate gut-genome interactions in chicken fat metabolism, paving the way for more effective breeding and microbiome-based strategies to manage adiposity in poultry.