The Gut Microbiome Contributes to a Substantial Proportion of the Variation in Blood Lipids

Anticancer Potential of Postbiotic Derived from Lactobacillus brevis and Lactobacillus casei: In vitro Analysis of Breast Cancer Cell Line

Breast cancer has emerged as the most widespread and dangerous type of malignancy among women worldwide. Postbiotics have recently emerged as a promising novel adjunct in breast cancer therapy, due to their immunomodulatory effects and the potential to mitigate the adverse effects of conventional treatments. This study aims to investigate the therapeutic effects of postbiotics derived from Lactobacillus brevis (CSF2) and Lactobacillus casei (CFS5), specifically examining their ability to inhibit cell proliferation and induce apoptosis in MCF-7 breast cancer cells. In the current study, the anticancer activity of the cell-free supernatant of L. brevis and L. casei was investigated against MCF-7 cells using MTT assay, flow cytometry, and qRT-PCR technique. Both bacteria showed a high potential for the induction of cell death in MCF-7 cells. However, CFS2 cytotoxicity was significantly higher than CFS5. Flow cytometry results showed significant induction of early apoptosis in cells treated with both CFS2 and CFS5 within 48 h. The induction was notably higher in cells treated with CFS2 compared to CFS5. Overall, CFS2 therapy resulted in a greater increase in BAX and CASP9 gene expression, as well as an elevated BAX/BCL2 ratio within 48 h. These findings indicate that the CFS2 treatment showed a higher level of apoptotic activity than the CFS5 treatment. High biocompatibility was demonstrated following treatment with CFS2 and CFS5. These CFSs may serve as adjunctive medications for suppressing the proliferation of cancer cells. The results of the current study highlight the potential of postbiotics in cancer treatment and suggest that supernatants may serve as effective agents for suppressing cancer cell growth and viability.

Characterization of the gut microbiota in polycystic ovary syndrome with dyslipidemia

BACKGROUND

Polycystic ovary syndrome (PCOS) is an endocrinopathy in childbearing-age females which can cause many complications, such as diabetes, obesity, and dyslipidemia. The metabolic disorders in patients with PCOS were linked to gut microbial dysbiosis. However, the correlation between the gut microbial community and dyslipidemia in PCOS remains unillustrated. Our study elucidated the different gut microbiota in patients with PCOS and dyslipidemia (PCOS.D) compared to those with only PCOS and healthy women.

RESULTS

In total, 18 patients with PCOS, 16 healthy females, and 18 patients with PCOS.D were enrolled. The 16 S rRNA sequencing in V3-V4 region was utilized for identifying the gut microbiota, which analyzes species annotation, community diversity, and community functions. Our results showed that the β diversity of gut microbiota did not differ significantly among the three groups. Regarding gut microbiota dysbiosis, patients with PCOS showed a decreased abundance of Proteobacteria, and patients with PCOS.D showed an increased abundance of Bacteroidota compared to other groups. With respect to the gut microbial imbalance at genus level, the PCOS.D group showed a higher abundance of Clostridium_sensu_stricto_1 compared to other two groups. Furthermore, the abundances of Faecalibacterium and Holdemanella were lower in the PCOS.D than those in the PCOS group. Several genera, including Faecalibacterium and Holdemanella, were negatively correlated with the lipid profiles. Pseudomonas was negatively correlated with luteinizing hormone levels. Using PICRUSt analysis, the gut microbiota community functions suggested that certain metabolic pathways (e.g., amino acids, glycolysis, and lipid) were altered in PCOS.D patients as compared to those in PCOS patients.

CONCLUSIONS

The gut microbiota characterizations in patients with PCOS.D differ from those in patients with PCOS and controls, and those might also be related to clinical parameters. This may have the potential to become an alternative therapy to regulate the clinical lipid levels of patients with PCOS in the future.

Biogeography of intestinal mucus-associated microbiome: Depletion of genus Pseudomonas is associated with depressive-like behaviors in female cynomolgus macaques

INTRODUCTION

Depression is a debilitating and poorly understood mental disorder. There is an urgency to explore new potential biological mechanisms of depression and the gut microbiota is a promising research area.

OBJECTIVES

Our study was aim to understand regional heterogeneity and potential molecular mechanisms underlying depression induced by dysbiosis of mucus-associated microbiota.

METHODS

Here, we only selected female macaques because they are more likely to form a natural social hierarchy in a harem-like environment. Because high-ranking macaques rarely displayed depressive-like behaviors, we selected seven monkeys from high-ranking individuals as control group (HC) and the same number of low-ranking ones as depressive-like group (DL), which displayed significant depressive-like behaviors. Then, we collected mucus from the duodenum, jejunum, ileum, cecum and colon of DL and HC monkeys for shotgun metagenomic sequencing, to profile the biogeography of mucus-associated microbiota along duodenum to colon.

RESULTS

Compared with HC, DL macaques displayed noticeable depressive-like behaviors such as longer duration of huddle and sit alone behaviors (negative emotion behaviors), and fewer duration of locomotion, amicable and ingestion activities (positive emotion behaviors). Moreover, the alpha diversity index (Chao) could predict aforementioned depressive-like behaviors along duodenum to colon. Further, we identified that genus Pseudomonas was consistently decreased in DL group throughout the entire intestinal tract except for the jejunum. Specifically, there were 10, 18 and 28 decreased Pseudomonas spp. identified in ileum, cecum and colon, respectively. Moreover, a bacterial module mainly composed of Pseudomonas spp. was positively associated with three positive emotion behaviors. Functionally, Pseudomonaswas mainly involved in microbiota derived lipid metabolisms such as PPAR signaling pathway, cholesterol metabolism, and fat digestion and absorption.

CONCLUSION

Different regions of intestinal mucus-associated microbiota revealed that depletion of genus Pseudomonas is associated with depressive-like behaviors in female macaques, which might induce depressive phenotypes through regulating lipid metabolism.

Gut microbial metabolism is linked to variations in circulating non-high density lipoprotein cholesterol

BACKGROUND

Non-high-density lipoprotein cholesterol (non-HDL-c) was a strong risk factor for incident cardiovascular diseases and proved to be a better target of lipid-lowering therapies. Recently, gut microbiota has been implicated in the regulation of host metabolism. However, its causal role in the variation of non-HDL-c remains unclear.

METHODS

Microbial species and metabolic capacities were assessed with fecal metagenomics, and their associations with non-HDL-c were evaluated by Spearman correlation, followed by LASSO and linear regression adjusted for established cardiovascular risk factors. Moreover, integrative analysis with plasma metabolomics were performed to determine the key molecules linking microbial metabolism and variation of non-HDL-c. Furthermore, bi-directional mendelian randomization analysis was performed to determine the potential causal associations of selected species and metabolites with non-HDL-c.

FINDINGS

Decreased Eubacterium rectale but increased Clostridium sp CAG_299 were causally linked to a higher level of non-HDL-c. A total of 16 microbial capacities were found to be independently associated with non-HDL-c after correcting for age, sex, demographics, lifestyles and comorbidities, with the strongest association observed for tricarboxylic acid (TCA) cycle. Furthermore, decreased 3-indolepropionic acid and N-methyltryptamine, resulting from suppressed capacities for microbial reductive TCA cycle, functioned as major microbial effectors to the elevation of circulating non-HDL-c.

INTERPRETATION

Overall, our findings provided insight into the causal effects of gut microbes on non-HDL-c and uncovered a novel link between non-HDL-c and microbial metabolism, highlighting the possibility of regulating non-HDL-c by microbiota-modifying interventions.

FUNDING

A full list of funding bodies can be found in the Sources of funding section.

Role of Gut Microbe Composition in Psychosocial Symptom Response to Exercise Training in Breast Cancer Survivors (ROME) study: protocol for a randomised controlled trial

INTRODUCTION

Breast cancer survivors have an increased risk for chronic fatigue and altered gut microbiota composition, both with negative health and quality of life affects. Exercise modestly improves fatigue and is linked to gut microbial diversity and production of beneficial metabolites. Studies suggest that gut microbiota composition is a potential mechanism underlying fatigue response to exercise. Randomised controlled trials testing the effects of exercise on the gut microbiome are limited and there is a scarcity of findings specific to breast cancer survivors. The objective of this study is to determine if fitness-related modifications to gut microbiota occur and, if so, mediate the effects of aerobic exercise on fatigue response.

METHODS AND ANALYSIS

The research is a randomised controlled trial among breast cancer survivors aged 18-74 with fatigue. The primary aim is to determine the effects of aerobic exercise training compared with an attention control on gut microbiota composition. The secondary study aims are to test if exercise training (1) affects the gut microbiota composition directly and/or indirectly through inflammation (serum cytokines), autonomic nervous system (heart rate variability) or hypothalamic-pituitary-adrenal axis mediators (hair cortisol assays), and (2) effects on fatigue are direct and/or indirect through changes in the gut microbiota composition. All participants receive a standardised controlled diet. Assessments occur at baseline, 5 weeks, 10 weeks and 15 weeks (5 weeks post intervention completion). Faecal samples collect the gut microbiome and 16S gene sequencing will identify the microbiome. Fatigue is measured by a 13-item multidimensional fatigue scale.

ETHICS AND DISSEMINATION

The University of Alabama at Birmingham Institutional Review Board (IRB) approved this study on 15 May 2019, UAB IRB#30000320. A Data and Safety Monitoring Board convenes annually or more often if indicated. Findings will be disseminated in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT04088708.

The Role of Gut Microbiota in the Etiopathogenesis of Multiple Chronic Diseases

Chronic diseases (CD) may result from a combination of genetic factors, lifestyle and social behaviours, healthcare system influences, community factors, and environmental determinants of health. These risk factors frequently coexist and interact with one another. Ongoing research and a focus on personalized interventions are pivotal strategies for preventing and managing chronic disease outcomes. A wealth of literature suggests the potential involvement of gut microbiota in influencing host metabolism, thereby impacting various risk factors associated with chronic diseases. Dysbiosis, the perturbation of the composition and activity of the gut microbiota, is crucial in the etiopathogenesis of multiple CD. Recent studies indicate that specific microorganism-derived metabolites, including trimethylamine N-oxide, lipopolysaccharide and uremic toxins, contribute to subclinical inflammatory processes implicated in CD. Various factors, including diet, lifestyle, and medications, can alter the taxonomic species or abundance of gut microbiota. Researchers are currently dedicating efforts to understanding how the natural progression of microbiome development in humans affects health outcomes. Simultaneously, there is a focus on enhancing the understanding of microbiome-host molecular interactions. These endeavours ultimately aim to devise practical approaches for rehabilitating dysregulated human microbial ecosystems, intending to restore health and prevent diseases. This review investigates how the gut microbiome contributes to CD and explains ways to modulate it for managing or preventing chronic conditions.

The Water Extract of Rhubarb Prevents Ischemic Stroke by Regulating Gut Bacteria and Metabolic Pathways

Rhubarb (RR), Chinese name Dahuang, is commonly used in the treatment of ischemic stroke (IS). However, its potential mechanism is not fully elucidated. This study intended to verify the effect of RR on IS and investigate the possible mechanism of RR in preventing IS. IS in male rats was induced by embolic middle cerebral artery occlusion (MCAO) surgery, and drug administration was applied half an hour before surgery. RR dramatically decreased the neurological deficit scores, the cerebral infarct volume, and the cerebral edema rate, and improved the regional cerebral blood flow (rCBF) and histopathological changes in the brain of MCAO rats. The 16S rRNA analysis showed the harmful microbes such as Fournierella and Bilophila were decreased, and the beneficial microbes such as Enterorhabdus, Defluviitaleaceae, Christensenellaceae, and Lachnospira were significantly increased, after RR pretreatment. 1H-nuclear magnetic resonance (1H-NMR) was used to detect serum metabolomics, and RR treatment significantly changed the levels of metabolites such as isoleucine, valine, N6-acetyllysine, methionine, 3-aminoisobutyric acid, N, N-dimethylglycine, propylene glycol, trimethylamine N-oxide, myo-inositol, choline, betaine, lactate, glucose, and lipid, and the enrichment analysis of differential metabolites showed that RR may participate in the regulation of amino acid metabolism and energy metabolism. RR exerts the role of anti-IS via regulating gut bacteria and metabolic pathways.

Gut microbiome and metabolome profiling in Framingham heart study reveals cholesterol-metabolizing bacteria

Accumulating evidence suggests that cardiovascular disease (CVD) is associated with an altered gut microbiome. Our understanding of the underlying mechanisms has been hindered by lack of matched multi-omic data with diagnostic biomarkers. To comprehensively profile gut microbiome contributions to CVD, we generated stool metagenomics and metabolomics from 1,429 Framingham Heart Study participants. We identified blood lipids and cardiovascular health measurements associated with microbiome and metabolome composition. Integrated analysis revealed microbial pathways implicated in CVD, including flavonoid, γ-butyrobetaine, and cholesterol metabolism. Species from the Oscillibacter genus were associated with decreased fecal and plasma cholesterol levels. Using functional prediction and in vitro characterization of multiple representative human gut Oscillibacter isolates, we uncovered conserved cholesterol-metabolizing capabilities, including glycosylation and dehydrogenation. These findings suggest that cholesterol metabolism is a broad property of phylogenetically diverse Oscillibacter spp., with potential benefits for lipid homeostasis and cardiovascular health.

Ischaemic heart disease in patients with cancer

Cardiologists are encountering a growing number of cancer patients with ischaemic heart disease (IHD). Several factors account for the interrelationship between these two conditions, in addition to improving survival rates in the cancer population. Established cardiovascular (CV) risk factors, such as hypercholesterolaemia and obesity, predispose to both IHD and cancer, through specific mechanisms and via low-grade, systemic inflammation. This latter is also fuelled by clonal haematopoiesis of indeterminate potential. Furthermore, experimental work indicates that IHD and cancer can promote one another, and the CV or metabolic toxicity of anticancer therapies can lead to IHD. The connections between IHD and cancer are reinforced by social determinants of health, non-medical factors that modify health outcomes and comprise individual and societal domains, including economic stability, educational and healthcare access and quality, neighbourhood and built environment, and social and community context. Management of IHD in cancer patients is often challenging, due to atypical presentation, increased bleeding and ischaemic risk, and worse outcomes as compared to patients without cancer. The decision to proceed with coronary revascularization and the choice of antithrombotic therapy can be difficult, particularly in patients with chronic coronary syndromes, necessitating multidisciplinary discussion that considers both general guidelines and specific features on a case by case basis. Randomized controlled trial evidence in cancer patients is very limited and there is urgent need for more data to inform clinical practice. Therefore, coexistence of IHD and cancer raises important scientific and practical questions that call for collaborative efforts from the cardio-oncology, cardiology, and oncology communities.

Exploring of gut microbiota features in dyslipidemia and chronic coronary syndrome patients undergoing coronary angiography

Chronic coronary syndrome (CCS) has a high mortality rate, and dyslipidemia is a major risk factor. Atherosclerosis, a cause of CCS, is influenced by gut microbiota dysbiosis and its metabolites. The objective of this study was to study the diversity and composition of gut microbiota and related clinical parameters among CCS patients undergoing coronary angiography and dyslipidemia patients in comparison to healthy volunteers in Thailand. CCS patients had more risk factors and higher inflammatory markers, high-sensitivity C-reactive protein (hs-CRP) than others. The alpha diversity was lower in dyslipidemia and CCS patients than in the healthy group. A significant difference in the composition of gut microbiota was observed among the three groups. The relative abundance of Proteobacteria, Fusobacteria, Enterobacteriaceae, Prevotella, and Streptococcus was significantly increased while Roseburia, Ruminococcus, and Faecalibacterium were lower in CCS patients. In CCS patients, Lachnospiraceae, Peptostreptococcaceae, and Pediococcus were positively correlated with hs-CRP. In dyslipidemia patients, Megasphaera was strongly positively correlated with triglyceride (TG) level and negatively correlated with high-density lipoprotein cholesterol (HDL-C). The modification of gut microbiota was associated with changes in clinical parameters involved in the development of coronary artery disease (CAD) in CCS patients.

Ethnic variations in metabolic syndrome components and their associations with the gut microbiota: the HELIUS study

BACKGROUND

The occurrence of metabolic syndrome (MetS) and the gut microbiota composition are known to differ across ethnicities yet how these three factors are interwoven is unknown. Also, it is unknown what the relative contribution of the gut microbiota composition is to each MetS component and whether this differs between ethnicities. We therefore determined the occurrence of MetS and its components in the multi-ethnic HELIUS cohort and tested the overall and ethnic-specific associations with the gut microbiota composition.

METHODS

We included 16,209 treatment naïve participants of the HELIUS study, which were of Dutch, African Surinamese, South-Asian Surinamese, Ghanaian, Turkish, and Moroccan descent to analyze MetS and its components across ethnicities. In a subset (n = 3443), the gut microbiota composition (16S) was associated with MetS outcomes using linear and logistic regression models.

RESULTS

A differential, often sex-dependent, prevalence of MetS components and their combinations were observed across ethnicities. Increased blood pressure was commonly seen especially in Ghanaians, while South-Asian Surinamese and Turkish had higher MetS rates in general and were characterized by worse lipid-related measures. Regarding the gut microbiota, when ethnic-independent associations were assumed, a higher α-diversity, higher abundance of several ASVs (mostly for waist and triglyceride-related outcomes) and a trophic network of ASVs of Ruminococcaceae, Christensenellaceae, and Methanobrevibacter (RCM) bacteria were associated with better MetS outcomes. Statistically significant ethnic-specific associations were however noticed for α-diversity and the RCM trophic network. Associations were significant in the Dutch but not always in all other ethnicities. In Ghanaians, a higher α-diversity and RCM network abundance showed an aberrant positive association with high blood pressure measures compared to the other ethnicities. Even though adjustment for socioeconomic status-, lifestyle-, and diet-related variables often attenuated the effect size and/or the statistical significance of the ethnic-specific associations, an overall similar pattern across outcomes and ethnicities remained.

CONCLUSIONS

The occurrence of MetS characteristics among ethnicities is heterogeneous. Both ethnic-independent and ethnic-specific associations were identified between the gut microbiota and MetS outcomes. Across multiple ethnicities, a one-size-fits-all approach may thus be reconsidered in regard to both the definition and/or treatment of MetS and its relation to the gut microbiota.

Alistipes indistinctus-derived hippuric acid promotes intestinal urate excretion to alleviate hyperuricemia

Hyperuricemia induces inflammatory arthritis and accelerates the progression of renal and cardiovascular diseases. Gut microbiota has been linked to the development of hyperuricemia through unclear mechanisms. Here, we show that the abundance and centrality of Alistipes indistinctus are depleted in subjects with hyperuricemia. Integrative metagenomic and metabolomic analysis identified hippuric acid as the key microbial effector that mediates the uric-acid-lowering effect of A. indistinctus. Mechanistically, A. indistinctus-derived hippuric acid enhances the binding of peroxisome-proliferator-activated receptor γ (PPARγ) to the promoter of ATP-binding cassette subfamily G member 2 (ABCG2), which in turn boosts intestinal urate excretion. To facilitate this enhanced excretion, hippuric acid also promotes ABCG2 localization to the brush border membranes in a PDZ-domain-containing 1 (PDZK1)-dependent manner. These findings indicate that A. indistinctus and hippuric acid promote intestinal urate excretion and offer insights into microbiota-host crosstalk in the maintenance of uric acid homeostasis.

Systems genetics approach uncovers associations between host amylase locus, gut microbiome and metabolic traits in hyperlipidemic mice

The molecular basis for how host genetic variation impacts gut microbial community and bacterial metabolic niches remain largely unknown. We leveraged 90 inbred hyperlipidemic mouse strains from the Hybrid Mouse Diversity Panel (HMDP), previously studied for a variety of cardio-metabolic traits. Metagenomic analysis of cecal DNA followed by genome-wide association analysis identified genomic loci that were associated with microbial enterotypes in the gut. Among these we detected a genetic locus surrounding multiple amylase genes that was associated with abundances of Firmicutes (Lachnospiraceae family) and Bacteroidetes (Muribaculaceae family) taxa encoding distinct starch and sugar metabolism functions. We also found that lower amylase gene number in the mouse genome was associated with higher gut Muribaculaceae levels. Previous work suggests that modulation of host amylase activity impacts the availability of carbohydrates to the host and potentially to gut bacteria. The genetic variants described above were associated with distinct gut microbial communities (enterotypes) with different predicted metabolic capacities for carbohydrate degradation. Mendelian randomization analysis revealed host phenotypes, including liver fibrosis and plasma HDL-cholesterol levels, that were associated with gut microbiome enterotypes. This work reveals novel relationships between host genetic variation, gut microbial enterotypes and host physiology/disease phenotypes in mice.

Causality of the gut microbiome and atherosclerosis-related lipids: a bidirectional Mendelian Randomization study

AIMS

Recent studies have indicated an association between intestinal flora and lipids. However, observational studies cannot indicate causality. In this study, we aimed to investigate the potentially causal relationships between the intestinal flora and blood lipids.

METHODS

We performed a bidirectional two-sample Mendelian Randomization (MR) analysis to investigate the causal relationship between intestinal flora and blood lipids. Summary statistics of genome-wide association studies (GWASs) for the 211 intestinal flora and blood lipid traits (n = 5) were obtained from public datasets. Five recognized MR methods were applied to assess the causal relationship with lipids, among which, the inverse-variance weighted (IVW) regression was used as the primary MR method. A series of sensitivity analyses were performed to test the robustness of the causal estimates.

RESULTS

The results indicated a potential causal association between 19 intestinal flora and dyslipidemia in humans. Genus Ruminococcaceae, Christensenellaceae, Parasutterella, Terrisporobacter, Parabacteroides, Class Erysipelotrichia, Family Erysipelotrichaceae, and order Erysipelotrichales were associated with higher dyslipidemia, whereas genus Oscillospira, Peptococcus, Ruminococcaceae UCG010, Ruminococcaceae UCG011, Dorea, and Family Desulfovibrionaceae were associated with lower dyslipidemia. After using the Bonferroni method for multiple testing correction, Only Desulfovibrionaceae [Estimate = -0.0418, 95% confidence interval [CI]: 0.9362-0.9826, P = 0.0007] exhibited stable and significant negative associations with ApoB levels. The inverse MR analysis did not find a significant causal effect of lipids on the intestinal flora. Additionally, no significant heterogeneity or horizontal pleiotropy for IVs was observed in the analysis.

CONCLUSION

The study suggested a causal relationship between intestinal flora and dyslipidemia. These findings will provide a meaningful reference to discover dyslipidemia for intervention to address the problems in the clinic.

The Women4Health cohort: a unique cohort to study women-specific mechanisms of cardio-metabolic regulation

Aims

Epidemiological research has shown relevant differences between sexes in clinical manifestations, severity, and progression of cardiovascular and metabolic disorders. To date, the mechanisms underlying these differences remain unknown. Given the rising incidence of such diseases, gender-specific research on established and emerging risk factors, such as dysfunction of glycaemic and/or lipid metabolism, of sex hormones and of gut microbiome, is of paramount importance. The relationships between sex hormones, gut microbiome, and host glycaemic and/or lipid metabolism are largely unknown even in the homoeostasis status. Yet this knowledge gap would be pivotal to pinpoint to key mechanisms that are likely to be disrupted in disease context.

Methods and results

Here we present the Women4Health (W4H) cohort, a unique cohort comprising up to 300 healthy women followed up during a natural menstrual cycle, set up with the primary goal to investigate the combined role of sex hormones and gut microbiota variations in regulating host lipid and glucose metabolism during homoeostasis, using a multi-omics strategy. Additionally, the W4H cohort will take into consideration another ecosystem that is unique to women, the vaginal microbiome, investigating its interaction with gut microbiome and exploring-for the first time-its role in cardiometabolic disorders.

Conclusion

The W4H cohort study lays a foundation for improving current knowledge of women-specific mechanisms in cardiometabolic regulation. It aspires to transform insights on host-microbiota interactions into prevention and therapeutic approaches for personalized health care.

Electroacupuncture at ST25 corrected gut microbial dysbiosis and SNpc lipid peroxidation in Parkinson's disease rats

Introduction

Parkinson's disease (PD) remains one kind of a complex, progressive neurodegenerative disease. Levodopa and dopamine agonists as widely utilized PD therapeutics have not shown significant positive long-term outcomes. Emerging evidences indicate that electroacupuncture (EA) have potential effects on the therapy of nervous system disorders, particularly PD, but its specific underlying mechanism(s) remains poorly understood, leading to the great challenge of clinical application and management. Previous study has shown that acupuncture ameliorates PD motor symptoms and dopaminergic neuron damage by modulating intestinal dysbiosis, but its intermediate pathway has not been sufficiently investigated.

Methods

A rat model of PD was induced using rotenone. The therapeutic effect of EA on PD was assessed using the pole and rotarod tests and immunohistostaining for tyrosine hydroxylase (TH) in the substantia nigra (SN) of brain. The role of gut microbiota was explored using 16S rRNA gene sequencing and metabonomic analysis. PICRUSt2 analysis, lipidomic analysis, LPS and inflammatory factor assays were used for subsequent exploration and validation. Correlation analysis was used to identify the key bacteria that EA regulates lipid metabolism to improve PD.

Results

The present study firstly reappeared the effects of EA on protecting motor function and dopaminergic neurons and modulation of gut microbial dysbiosis in rotenone-induced PD rat model. EA improved motor dysfunction (via the pole and rotarod tests) and protected TH+ neurons in PD rats. EA increased the abundance of beneficial bacteria such as Lactobacillus, Dubosiella and Bifidobacterium and decreased the abundance of Escherichia-Shigella and Morganella belonging to Pseudomonadota, suggesting that the modulation of gut microbiota by EA improving the symptoms of PD motility via alleviating LPS-induced inflammatory response and oxidative stress, which was also validated by various aspects such as microbial gene functional analysis, fecal metabolomics analysis, LPS and inflammatory factor assays and SNpc lipidomics analysis. Moreover, correlation analyses also verified strong correlations of Escherichia-Shigella and Morganella with motor symptoms and SNpc lipid peroxidation, explicating targets and intermediate pathways through which EA improve PD exercise symptom.

Conclusion

Our results indicate that the improvement of motor function in PD model by EA may be mediated in part by restoring the gut microbiota, which intermediate processes involve circulating endotoxins and inflammatory mediators, SNpc oxidative stress and lipid peroxidation. The gut-microbiome - brain axis may be a potential mechanism of EA treatment for the PD.

Christensenella minuta interacts with multiple gut bacteria

Introduction

Gut microbes form complex networks that significantly influence host health and disease treatment. Interventions with the probiotic bacteria on the gut microbiota have been demonstrated to improve host well-being. As a representative of next-generation probiotics, Christensenella minuta (C. minuta) plays a critical role in regulating energy balance and metabolic homeostasis in human bodies, showing potential in treating metabolic disorders and reducing inflammation. However, interactions of C. minuta with the members of the networked gut microbiota have rarely been explored.

Methods

In this study, we investigated the impact of C. minuta on fecal microbiota via metagenomic sequencing, focusing on retrieving bacterial strains and coculture assays of C. minuta with associated microbial partners.

Results

Our results showed that C. minuta intervention significantly reduced the diversity of fecal microorganisms, but specifically enhanced some groups of bacteria, such as Lactobacillaceae. C. minuta selectively enriched bacterial pathways that compensated for its metabolic defects on vitamin B1, B12, serine, and glutamate synthesis. Meanwhile, C. minuta cross-feeds Faecalibacterium prausnitzii and other bacteria via the production of arginine, branched-chain amino acids, fumaric acids and short-chain fatty acids (SCFAs), such as acetic. Both metagenomic data analysis and culture experiments revealed that C. minuta negatively correlated with Klebsiella pneumoniae and 14 other bacterial taxa, while positively correlated with F. prausnitzii. Our results advance our comprehension of C. minuta's in modulating the gut microbial network.

Conclusions

C. minuta disrupts the composition of the fecal microbiota. This disturbance is manifested through cross-feeding, nutritional competition, and supplementation of its own metabolic deficiencies, resulting in the specific enrichment or inhibition of the growth of certain bacteria. This study will shed light on the application of C. minuta as a probiotic for effective interventions on gut microbiomes and improvement of host health.

A study on the association between gut microbiota, inflammation, and type 2 diabetes

Type 2 diabetes mellitus (T2DM) was reported to be associated with impaired immune response and alterations in microbial composition and function. However, the underlying mechanism remains elusive. To investigate the association among retinoic acid-inducible gene-I-like receptors (RLRs) signaling pathway, intestinal bacterial microbiome, microbial tryptophan metabolites, inflammation, and a longer course of T2DM, 14 patients with T2DM and 7 healthy controls were enrolled. 16S rRNA amplicon sequencing and untargeted metabolomics were utilized to analyze the stool samples. RNA sequencing (RNA-seq) was carried out on the peripheral blood samples. Additionally, C57BL/6J specific pathogen-free (SPF) mice were used. It was found that the longer course of T2DM could lead to a decrease in the abundance of probiotics in the intestinal microbiome. In addition, the production of microbial tryptophan derivative skatole declined as a consequence of the reduced abundance of related intestinal microbes. Furthermore, low abundances of probiotics, such as Bacteroides and Faecalibacterium, could trigger the inflammatory response by activating the RLRs signaling pathway. The increased level of the member of TNF receptor-associated factors (TRAF) family, nuclear factor kappa-B (NF-κB) activator (TANK), in the animal colon activated nuclear factor kappa B subunit 2 (NFκB2), resulting in inflammatory damage. In summary, it was revealed that the low abundances of probiotics could activate the RLR signaling pathway, which could in turn activate its downstream signaling pathway, NF-κB, highlighting a relationship among gut microbes, inflammation, and a longer course of T2DM. KEY POINTS: Hyperglycemia may suppress tryptophanase activity. The low abundance of Bacteroides combined with the decrease of Dopa decarboxylase (DDC) activity may lead to the decrease of the production of tryptophan microbial derivative skatole, and the low abundance of Bacteroides or reduced skatole may further lead to the increase of blood glucose by downregulating the expression of glucagon-like peptide-1 (GLP1). A low abundance of anti-inflammatory bacteria may induce an inflammatory response by triggering the RLR signaling pathway and then activating its downstream NF-κB signaling pathway in prolonged T2DM.

Revisiting multi-omics-based predictors of the plasma triglyceride response to an omega-3 fatty acid supplementation

Background

The aim of the present study was to identify the metabolomic signature of responders and non-responders to an omega-3 fatty acid (n-3 FA) supplementation, and to test the ability of a multi-omics classifier combining genomic, lipidomic, and metabolomic features to discriminate plasma triglyceride (TG) response phenotypes.

Methods

A total of 208 participants of the Fatty Acid Sensor (FAS). Study took 5 g per day of fish oil, providing 1.9-2.2 g eicosapentaenoic acid (EPA) and 1.1 g docosahexaenoic (DHA) daily over a 6-week period, and were further divided into two subgroups: responders and non-responders, according to the change in plasma TG levels after the supplementation. Changes in plasma levels of 6 short-chain fatty acids (SCFA) and 25 bile acids (BA) during the intervention were compared between subgroups using a linear mixed model, and the impact of SCFAs and BAs on the TG response was tested in a mediation analysis. Genotyping was conducted using the Illumina Human Omni-5 Quad BeadChip. Mass spectrometry was used to quantify plasma TG and cholesterol esters levels, as well as plasma SCFA and BA levels. A classifier was developed and tested within the DIABLO framework, which implements a partial least squares-discriminant analysis to multi-omics analysis. Different classifiers were developed by combining data from genomics, lipidomics, and metabolomics.

Results

Plasma levels of none of the SCFAs or BAs measured before and after the n-3 FA supplementation were significantly different between responders and non-responders. SCFAs but not BAs were marginally relevant in the classification of plasma TG responses. A classifier built by adding plasma SCFAs and lipidomic layers to genomic data was able to even the accuracy of 85% shown by the genomic predictor alone.

Conclusion

These results inform on the marginal relevance of SCFA and BA plasma levels as surrogate measures of gut microbiome in the assessment of the interindividual variability observed in the plasma TG response to an n-3 FA supplementation. Genomic data still represent the best predictor of plasma TG response, and the inclusion of metabolomic data added little to the ability to discriminate the plasma TG response phenotypes.

What are the common downstream molecular events between alcoholic and nonalcoholic fatty liver?

Liver fat storage, also called hepatic steatosis, is increasingly common and represents a very frequent diagnosis in the medical field. Excess fat is not without consequences. In fact, hepatic steatosis contributes to the progression toward liver fibrosis. There are two main types of fatty liver disease, alcoholic fatty liver disease (AFLD) and nonalcoholic fatty liver disease (NAFLD). Although AFLD and NAFLD are similar in their initial morphological features, both conditions involve the same evolutive forms. Moreover, there are various common mechanisms underlying both diseases, including alcoholic liver disease and NAFLD, which are commonalities. In this Review, the authors explore similar downstream signaling events involved in the onset and progression of the two entities but not completely different entities, predominantly focusing on the gut microbiome. Downstream molecular events, such as the roles of sirtuins, cytokeratins, adipokines and others, should be considered. Finally, to complete the feature, some new tendencies in the therapeutic approach are presented.

Role of Gut Microbiota in Statin-Associated New-Onset Diabetes-A Cross-Sectional and Prospective Analysis of the FINRISK 2002 Cohort

BACKGROUND

Dyslipidemia is treated effectively with statins, but treatment has the potential to induce new-onset type-2 diabetes. Gut microbiota may contribute to this outcome variability. We assessed the associations of gut microbiota diversity and composition with statins. Bacterial associations with statin-associated new-onset type-2 diabetes (T2D) risk were also prospectively evaluated.

METHODS

We examined shallow-shotgun-sequenced fecal samples from 5755 individuals in the FINRISK-2002 population cohort with a 17+-year-long register-based follow-up. Alpha-diversity was quantified using Shannon index and beta-diversity with Aitchison distance. Species-specific differential abundances were analyzed using general multivariate regression. Prospective associations were assessed with Cox regression. Applicable results were validated using gradient boosting.

RESULTS

Statin use associated with differing taxonomic composition (R2, 0.02%; q=0.02) and 13 differentially abundant species in fully adjusted models (MaAsLin; q<0.05). The strongest positive association was with Clostridium sartagoforme (β=0.37; SE=0.13; q=0.02) and the strongest negative association with Bacteroides cellulosilyticus (β=-0.31; SE=0.11; q=0.02). Twenty-five microbial features had significant associations with incident T2D in statin users, of which only Bacteroides vulgatus (HR, 1.286 [1.136-1.457]; q=0.03) was consistent regardless of model adjustment. Finally, higher statin-associated T2D risk was seen with [Ruminococcus] torques (ΔHRstatins, +0.11; q=0.03), Blautia obeum (ΔHRstatins, +0.06; q=0.01), Blautia sp. KLE 1732 (ΔHRstatins, +0.05; q=0.01), and beta-diversity principal component 1 (ΔHRstatin, +0.07; q=0.03) but only when adjusting for demographic covariates.

CONCLUSIONS

Statin users have compositionally differing microbiotas from nonusers. The human gut microbiota is associated with incident T2D risk in statin users and possibly has additive effects on statin-associated new-onset T2D risk.

The Effect of Fecal Microbiota Transplantation on Cardiometabolic Risk Factors: A Systematic Review and Meta-Analysis

PURPOSE

Cardiometabolic disease (CMD) is increasing along with its predisposing factors and adverse consequences. As gut microbiota dysbiosis is established in these patients, fecal microbiota transplantation (FMT), which alters the bacterial composition of the intestine, supposedly can help improve cardiometabolic disturbances. We conducted a systematic review and meta-analysis evaluating the impact of FMT on the cardiometabolic parameters and gut microbiota composition of patients experiencing at least one cardiometabolic issue.

METHODS

Eligible studies were searched through the PubMed, Web of Science, and Scopus databases until December 2022. The initial search results underwent duplication removal and screening until each included study was scanned for intended data. The Cochrane risk of bias tool was used to evaluate the methodologic accuracy of studies and the random effects model was used for conducting the meta-analysis.

FINDINGS

Eighteen of the original 2414 articles from the literature search were entered into the systematic review; of these, 11 were included in the meta-analysis. Insulin showed a significant decrease by 24.7 pmol/L (weighted mean difference [WMD], -24.77; 95% CI, -48.704 to -0.848) after short-term follow-up, and HDL increased by 0.1 mmol/l(WMD, 0.106; 95% CI, 0.027 to 0.184) and 0.12 mmol/l(WMD, 0.120; 95% CI, 0.003 to 0.237) in those using a capsule deliver mode and in short-term follow-up, respectively. No significant changes were seen in other lipid profiles, blood glucose, insulin resistance, or anthropometric indices. In addition, multiple studies reported gut microbiota alterations after the intervention, including an increase in butyrate-producing species.

IMPLICATIONS

Although some articles reported the beneficial effects of FMT on metabolic parameters, we failed to find a clinically significant alteration. Also, information regarding proper donors and the best method to induce FMT have not yet been sufficiently investigated, which should be considered along with means to prevent potential damages. PROSPERO identifier: CRD42022380705.

Targeting the Gut Microbiome to Treat Cardiometabolic Disease

PURPOSE OF REVIEW

Cardiometabolic diseases, which include obesity, type 2 diabetes, and cardiovascular diseases, constitute a worldwide health crisis of unparalleled proportions. The human gut microbiota has emerged as a prominent topic of inquiry in the search for novel treatment techniques. This review summarizes current research on the potential of addressing the gut microbiota to treat cardiometabolic disease.

RECENT FINDINGS

Recent studies have highlighted a complex link between the gut microbiota and host physiology, shedding light on the several processes through which gut microorganisms impact metabolic health, inflammation, and cardiovascular function. Furthermore, a growing corpus of research is available on microbiome-based therapies such as dietary interventions, probiotics, prebiotics, synbiotics, and fecal microbiota transplantation. These therapies show promise as methods for reshaping the gut microbiota and, as a result, improving cardiometabolic outcomes. However, hurdles remain, ranging from the intricacies of microbiome research to the necessity for tailored treatments that take individual microbial variations into consideration, emphasizing the significance of furthering research to bridge the gap between microbiome science and clinical practice. The gut microbiome is a beacon of hope for improving the management of cardiometabolic disease in the age of precision medicine, since its association with their pathophysiology is constantly being unraveled and strengthened. Available studies point to the potential of gut microbiome-based therapeutics, which remains to be tested in appropriately designed clinical trials. Further preclinical research is, however, essential to provide answers to the existing obstacles, with the ultimate goal of enhancing patient care.

Consumption of the Non-Nutritive Sweetener Stevia for 12 Weeks Does Not Alter the Composition of the Human Gut Microbiota

The use of non-nutritive sweeteners (NNSs) as an alternative to caloric sugars has increased in recent years. Stevia is an NNS that has demonstrated beneficial effects on appetite and energy intake. However, the impact on the gut microbiota is not well understood. Therefore, we investigated how regular consumption of stevia, for up to 12 weeks, impacts the human gut microbiota. Healthy subjects with a normal body mass index participated in our study; the stevia group (n = 14) was asked to consume five drops of stevia twice daily, compared to control participants (n = 13). Faecal samples collected before and after treatment were analysed by 16S rRNA gene sequencing. Stevia did not cause significant changes in the alpha or beta diversity when compared to the control groups. When the relative abundances of taxa were investigated, no clear differences were detected. Conversely, a random forest analysis correctly associated the gut microbiome with the control and stevia groups with an average of 75% accuracy, suggesting that there are intrinsic patterns that could discriminate between control and stevia use. However, large-scale changes in the gut microbiota were not apparent in this study, and, therefore, our data suggest that stevia does not significantly impact the gut microbiota.

Pioneering gut health improvements in piglets with phytogenic feed additives

This research investigates the effects of phytogenic feed additives (PFAs) on the growth performance, gut microbial community, and microbial metabolic functions in weaned piglets via a combined 16S rRNA gene amplicon and shotgun metagenomics approach. A controlled trial was conducted using 200 pigs to highlight the significant influence of PFAs on gut microbiota dynamics. Notably, the treatment group revealed an increased gut microbiota diversity, as measured with the Shannon and Simpson indices. The increase in diversity is accompanied by an increase in beneficial bacterial taxa, such as Roseburia, Faecalibacterium, and Prevotella, and a decline in potential pathogens like Clostridium sensu stricto 1 and Campylobacter. Shotgun sequencing at the species level confirmed these findings. This modification in microbial profile was coupled with an altered profile of microbial metabolic pathways, suggesting a reconfiguration of microbial function under PFA influence. Significant shifts in overall microbial community structure by week 8 demonstrate PFA treatment's temporal impact. Histomorphological examination unveiled improved gut structure in PFA-treated piglets. The results of this study indicate that the use of PFAs as dietary supplements can be an effective strategy, augmenting gut microbiota diversity, reshaping microbial function, enhancing gut structure, and optimising intestinal health of weaned piglets providing valuable implications for swine production. KEY POINTS: • PFAs significantly diversify the gut microbiota in weaned piglets, aiding balance. • Changes in gut structure due to PFAs indicate improved resistance to weaning stress. • PFAs show potential to ease weaning stress, offering a substitute for antibiotics in piglet diets.

Gut enterotype-dependent modulation of gut microbiota and their metabolism in response to xanthohumol supplementation in healthy adults

Xanthohumol (XN), a polyphenol found in the hop plant (Humulus lupulus), has antioxidant, anti-inflammatory, prebiotic, and anti-hyperlipidemic activity. Preclinical evidence suggests the gut microbiome is essential in mediating these bioactivities; however, relatively little is known about XN's impact on human gut microbiota in vivo. We conducted a randomized, triple-blinded, placebo-controlled clinical trial (ClinicalTrials.gov NCT03735420) to determine safety and tolerability of XN in healthy adults. Thirty healthy participants were randomized to 24 mg/day XN or placebo for 8 weeks. As secondary outcomes, quantification of bacterial metabolites and 16S rRNA gene sequencing were utilized to explore the relationships between XN supplementation, gut microbiota, and biomarkers of gut health. Although XN did not significantly change gut microbiota composition, it did re-shape individual taxa in an enterotype-dependent manner. High levels of inter-individual variation in metabolic profiles and bioavailability of XN metabolites were observed. Moreover, reductions in microbiota-derived bile acid metabolism were observed, which were specific to Prevotella and Ruminococcus enterotypes. These results suggest interactions between XN and gut microbiota in healthy adults are highly inter-individualized and potentially indicate that XN elicits effects on gut health in an enterotype-dependent manner.

Association of intestinal bacteria with immune activation in a cohort of healthy adults

IMPORTANCE

Chronic inflammation may develop over time in healthy adults as a result of a variety of factors, such as poor diet directly affecting the composition of the intestinal microbiome, or by causing obesity, which may also affect the intestinal microbiome. These effects may trigger the activation of an immune response that could eventually lead to an inflammation-related disease, such as colon cancer. Before disease develops it may be possible to identify subclinical inflammation or immune activation attributable to specific intestinal bacteria normally found in the gut that could result in future adverse health impacts. In the present study, we examined a group of healthy men and women across a wide age range with and without obesity to determine which bacteria were associated with particular types of immune activation to identify potential preclinical markers of inflammatory disease risk. Several associations were found that may help develop dietary interventions to lower disease risk.

Winds of change a tale of: asthma and microbiome

The role of the microbiome in asthma is highlighted, considering its influence on immune responses and its connection to alterations in asthmatic patients. In this context, we review the variables influencing asthma phenotypes from a microbiome perspective and provide insights into the microbiome's role in asthma pathogenesis. Previous cohort studies in patients with asthma have shown that the presence of genera such as Bifidobacterium, Lactobacillus, Faecalibacterium, and Bacteroides in the gut microbiome has been associated with protection against the disease. While, the presence of other genera such as Haemophilus, Streptococcus, Staphylococcus, and Moraxella in the respiratory microbiome has been implicated in asthma pathogenesis, indicating a potential link between microbial dysbiosis and the development of asthma. Furthermore, respiratory infections have been demonstrated to impact the composition of the upper respiratory tract microbiota, increasing susceptibility to bacterial diseases and potentially triggering asthma exacerbations. By understanding the interplay between the microbiome and asthma, valuable insights into disease mechanisms can be gained, potentially leading to the development of novel therapeutic approaches.

Metagenomic Analysis of Intratumoral Microbiome Linking to Response to Neoadjuvant Chemoradiotherapy in Rectal Cancer

PURPOSE

To assess taxonomic and functional characteristics of tumor-bearing microbiota and its association with response to neoadjuvant chemoradiation therapy (nCRT) in patients with locally advanced rectal cancer.

METHODS AND MATERIALS

We performed metagenomic sequencing of biopsy tumoral tissues from 73 patients with locally advanced rectal cancer before nCRT. Patients were classified into poor responders (PR) and good responders (GR) according to response to nCRT. Subsequent investigation of network alteration, key community, microbial biomarkers, and function related to nCRT responses were carried out.

RESULTS

The network-driven analysis systematically revealed 2 co-occurring bacteria modules that exhibited opposite relationship with rectal cancer radiosensitivity. In the 2 modules, prominent alteration of global graph properties and community structure was observed between networks of PR and GR group. By quantifying changes in between-group association patterns and abundances, a total of 115 discriminative biomarker species linked to nCRT response were found, and 35 microbial variables were selected to establish the optimal randomForest classifier for nCRT response prediction. It yielded an area under the curve value of 85.5% (95% CI, 73.3%-97.8%) in the training cohort and 88.4% (95% CI, 77.5%-99.4%) in the validation cohort. In a comprehensive consideration, 5 key bacteria showed high relevance with inducing resistance to nCRT, including Streptococcus equinus, Schaalia odontolytica, Clostridium hylemonae, Blautia producta, and Pseudomonas azotoformans. One key hub including several butyrate-formation bacteria involving with driving network alteration from GR to PR indicate that microbiota-derived butyrate may also be involved in reducing the antitumor effects of nCRT, especially Coprococcus. The functional analysis of metagenome linked the nitrate and sulfate-sulfur assimilation, histidine catabolic process, and resistance to cephamycin to the reduced therapeutic response. It also linked to leucine degradation, isoleucine biosynthesis, taurine, and hypotaurine metabolism to the improved response to nCRT.

CONCLUSIONS

Our data offer novel potential microbial factors and shared metagenome function linked to resistance to nCRT.

Parity modulates impact of BMI and gestational weight gain on gut microbiota in human pregnancy

Dysregulation of maternal adaptations to pregnancy due to high pre-pregnancy BMI (pBMI) or excess gestational weight gain (GWG) is associated with worsened health outcomes for mothers and children. Whether the gut microbiome contributes to these adaptations is unclear. We longitudinally investigated the impact of pBMI and GWG on the pregnant gut microbiome. We show that the gut microbiota of participants with higher pBMI changed less over the course of pregnancy in primiparous but not multiparous participants. This suggests that previous pregnancies may have persistent impacts on maternal adaptations to pregnancy. This ecological memory appears to be passed on to the next generation, as parity modulated the impact of maternal GWG on the infant gut microbiome. This work supports a role of the gut microbiome in maternal adaptations to pregnancy and highlights the need for longitudinal sampling and accounting for parity as key considerations for studies of the microbiome in pregnancy and infants. Understanding how these factors contribute to and shape maternal health is essential for the development of interventions impacting the microbiome, including pre/probiotics.

Gut microbiota regulates circadian oscillation in hepatic ischemia-reperfusion injury-induced cognitive impairment by interfering with hippocampal lipid metabolism in mice

BACKGROUND

Hepatic ischemia-reperfusion injury (HIRI) is a common complication of liver surgery, which can lead to extrahepatic metabolic disorders, such as cognitive impairment. Recent observations have emphasized the critical effects of gut microbial metabolites in regulating the development of liver injury. Herein, we investigated the potential contribution of gut microbiota to HIRI-related cognitive impairment.

METHODS

HIRI murine models were established by ischemia-reperfusion surgery in the morning (ZT0, 08:00) and evening (ZT12, 20:00), respectively. Antibiotic-induced pseudo-germ-free mice were gavaged with fecal bacteria of the HIRI models. Behavioral test was used to assess cognitive function. 16S rRNA gene sequencing and metabolomics were used for microbial and hippocampal analysis.

RESULTS

Our results established that cognitive impairment caused by HIRI underwent diurnal oscillations; HIRI mice performed poorly on the Y-maze test and the novel object preference test when surgery occurred in the evening compared with the morning. In addition, fecal microbiota transplantation (FMT) from the ZT12-HIRI was demonstrated to induce cognitive impairment behavior. The specific composition and metabolites of gut microbiota were analyzed between the ZT0-HIRI and ZT12-HIRI, and bioinformatic analysis showed that the differential fecal metabolites were significantly enriched in lipid metabolism pathways. After FMT, the hippocampal lipid metabolome between the P-ZT0-HIRI and P-ZT12-HIRI groups was analyzed to reveal a series of lipid molecules with significant differences.

CONCLUSIONS

Our findings indicate that gut microbiota are involved in circadian differences of HIRI-related cognitive impairment by affecting hippocampal lipid metabolism.

Intestinal Microbiota Community and Blood Fatty Acid Profiles of Albas Cashmere Goats Fed with Flaxseed Oil and Whole Flaxseed

The present study investigated the effects of flaxseed oil or flaxseed grain on the intestinal microbiota and blood fatty acid profiles of Albas cashmere goats. Sixty kid goats were allocated to three treatments and fed for 90 days with a control treatment, comprising a basal diet (CON, total-mixed ration with flaxseed meal), or experimental treatments, comprising a basal diet with added flaxseed oil (LNO) and a basal diet with added heated flaxseed grain (HLS). On day 90, two goats were randomly selected from each pen (eight goats per treatment) for euthanizing; then, five of the eight goats were randomly selected, and we collected their intestinal (duodenum, jejunum, ileum, cecum, and colon) digesta for analysis of the bacteria community. The results indicated that Firmicutes are the most predominant phylum in different segments of the intestinal digesta. Compared with the CON group, the relative abundance of duodenal Firmicutes, jejunal Saccharibacteria, and Verrucomicrobia significantly decreased in the LNO and HLS groups (p < 0.05), but there was no significant difference between the LNO and HLS groups. Compared with the CON and HLS groups, the RA of duodenal and jejunal Proteobacteria remarkably increased in the LNO group (p < 0.05), and there was no significant difference between the CON and HLS groups. Compared with the CON and LNO groups, the RA of Actinobacteria remarkably increased in the small intestine of the HLS group (p < 0.05), but there was no significant difference between the CON and LNO groups in the duodenum and ileum. The results of linear discriminant analysis (LDA) effect size (LEfSe) analysis showed that the HLS group was characterized by a higher RA of the [Eubacterium]_coprostanoligenes_group in the small intestine and the LNO group was represented by a higher RA of the Lachnospiraceae_NK3A20_group in the cecum and colon, while the CON group was represented by a higher RA of Solobacterium, Pseudoramibacter, and Acetitomaculum in the small intestine and a higher RA of norank_o__Bradymonadales, the Prevotellaceae_Ga6A1_group, and Ruminiclostridium_1 in the cecum and colon. In conclusion, the addition of flaxseed oil and grain rich in c18:3n3 to the diet could reduce the microbial diversity of the small intestinal segments and the microbial diversity and richness of the cecum and colon in Albas cashmere goats. And flaxseed grain is more efficient than flaxseed oil in protecting intestinal health and promoting the absorption of c18:3n3.

HuangQi ChiFeng decoction maintains gut microbiota and bile acid homeostasis through FXR signaling to improve atherosclerosis

Huangqi Chifeng Decoction (HQCFT), a traditional Chinese medicine preparation, has long been used to treat cardiovascular and cerebrovascular diseases. However, the mechanism of the beneficial effect of HQCFT on atherosclerosis remains to be explored. In this work, to investigate the effects of HQCFT on bile acid (BA) metabolism and the gut microbiome in atherosclerosis, ApoE-/- mice were fed a with high-fat diet for 16 weeks to establish the AS model. HQCFT(1.95 g kg-1 and 3.9 g kg-1 per day) was administered intragastrically for 8 weeks to investigate the regulatory effects of HQCFT on gut microbiota and bile acid metabolism and to inhibit the occurrence and development of AS induced by a high-fat diet. Histopathology, liver function and blood lipids were used to assess whether HQCFT can reduce plaque area, regulate lipid levels and alleviate liver steatosis in AS mice. In addition, 16S rDNA sequencing was used to screen the gut microbiota structure, and ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC‒MS/MS) was used to determine the bile acid profile. The mRNA and protein expression levels of bile acid metabolism were detected by RT‒PCR and WB to find the potential correlation. Results: HQCFT can regulate gut microbiota disorders, which was achieved by increasing gut microbiota diversity and altering Proteobacteria, Desulfobacterota, Deferribacteres, Rodentibacter, Parasutterella, and Mucispirillum interference abundance to improve AS-induced gut microbiota. HQCFT can also adjust the content of bile acids (TCA, LCA, DCA, TDCA, TLCA, UDCA, etc.), regulate bile acid metabolism, relieve liver fat accumulation, and inhibit the process of AS. In addition, HQCFT can restore the abnormal metabolism of bile acid caused by AS by regulating the expression of farnesoid X receptor (FXR), liver X receptor α (LXRα), ABCA1, ABCG1 and CYP7A1. Conclusion: HQCFT may play a part in the prevention of atherosclerosis by inhibiting the FXR/LXRα axis, increasing the expression of CYP7A1 in the liver, and regulating the interaction between the gut microbiota and bile acid metabolism.

Oral Porphyromonas gingivalis infection affects intestinal microbiota and promotes atherosclerosis

AIM

The link between periodontitis and intestinal dysbiosis, two factors that contribute to atherosclerosis, has not been clearly defined. We investigated the integrative effects of oral infection with Porphyromonas gingivalis (PG), the major pathogen for periodontitis, on intestinal microbiota and atherosclerosis.

MATERIALS AND METHODS

ApoE-/- mice were fed a normal chow diet (NC), a Western diet (WD) or a WD with oral PG infection (PG). The PG infection was investigated by placing a total of 109 CFUs of live PG into the oral cavity of each mouse using a feeding needle five times a week for 3 weeks. Atherosclerotic lesions of the aortae were measured, and blood lipoproteins and the expression of molecules related to lipid metabolism in the liver were analysed. We also performed 16S RNA sequencing and a microbiome analysis using faeces.

RESULTS

En face bloc preparation of the aortae showed that the PG group had a 1.7-fold increase in atherosclerotic lesions compared with the WD group (p < .01). Serum analyses showed that oral PG infection induced a significant decrease in high-density lipoprotein (HDL) and triglyceride. Western blots of hepatic tissue lysates revealed that PG infection reduced the expression of scavenger receptor class B type 1 (SR-B1) in the liver by 50%. Faecal microbiota analysis revealed that species richness estimates (Chao1, ACE) decreased immediately after PG infection. PG infection also induced a significant decrease in Shannon diversity and an increase in Simpson's indices in the WD-fed mice. PG infection significantly increased the phyla Actinobacteria and Deferribacteres, along with the species Mucispirillum schaedleri and Lactobacillus gasseri, in the mice. The functional study showed that PG infection increased the expression of proteins that function in carbohydrate and glucose metabolism, including phosphotransferase system (PTS) proteins and the GntR family transcriptional regulator.

CONCLUSIONS

Oral PG infection promotes atherosclerosis and induces significant metabolic changes, including reduced serum HDL and reduced hepatic SR-B1 and ABCA1 expression, as well as changes in intestinal microbiota. Our study suggests that intestinal dysbiosis accompanies periodontitis and could play a role in atherosclerosis.

Variations in the Relative Abundance of Gut Bacteria Correlate with Lipid Profiles in Healthy Adults

The gut microbiome is a versatile system regulating numerous aspects of host metabolism. Among other traits, variations in the composition of gut microbial communities are related to blood lipid patterns and hyperlipidaemia, yet inconsistent association patterns exist. This study aims to assess the relationships between the composition of the gut microbiome and variations in lipid profiles among healthy adults. This study used data and samples from 23 adult participants of a previously conducted dietary intervention study. Circulating lipid measurements and whole-metagenome sequences of the gut microbiome were derived from 180 blood and faecal samples collected from eight visits distributed across an 11-week study. Lipid-related variables explained approximately 4.5% of the variation in gut microbiome compositions, with higher effects observed for total cholesterol and high-density lipoproteins. Species from the genera Odoribacter, Anaerostipes, and Parabacteroides correlated with increased serum lipid levels, whereas probiotic species like Akkermansia muciniphila were more abundant among participants with healthier blood lipid profiles. An inverse correlation with serum cholesterol was also observed for Massilistercora timonensis, a player in regulating lipid turnover. The observed correlation patterns add to the growing evidence supporting the role of the gut microbiome as an essential regulator of host lipid metabolism.

Complete genome sequence of Butyricimonas faecihominis JCM 18676T

We report a complete genome sequence of Butyricimonas faecihominis JCM 18676T, generated by nanopore sequencing. The genome consists of a single circular chromosome of 4,851,806 bp, with a G + C content of 42.9%, and was predicted to contain 15 rRNA and 61 tRNA genes and encode for 3,946 proteins.

Connections between serum Trimethylamine N-Oxide (TMAO), a gut-derived metabolite, and vascular biomarkers evaluating arterial stiffness and subclinical atherosclerosis in children with obesity

Introduction

Childhood obesity leads to early subclinical atherosclerosis and arterial stiffness. Studying biomarkers like trimethylamine N-oxide (TMAO), linked to cardio-metabolic disorders in adults, is crucial to prevent long-term cardiovascular issues.

Methods

The study involved 70 children aged 4 to 18 (50 obese, 20 normal-weight). Clinical examination included BMI, waist measurements, puberty stage, the presence of acanthosis nigricans, and irregular menstrual cycles. Subclinical atherosclerosis was assessed by measuring the carotid intima-media thickness (CIMT), and the arterial stiffness was evaluated through surrogate markers like the pulse wave velocity (PWV), augmentation index (AIx), and peripheral and central blood pressures. The blood biomarkers included determining the values of TMAO, HOMA-IR, and other usual biomarkers investigating metabolism.

Results

The study detected significantly elevated levels of TMAO in obese children compared to controls. TMAO presented positive correlations to BMI, waist circumference and waist-to-height ratio and was also observed as an independent predictor of all three parameters. Significant correlations were observed between TMAO and vascular markers such as CIMT, PWV, and peripheral BP levels. TMAO independently predicts CIMT, PWV, peripheral BP, and central SBP levels, even after adding BMI, waist circumference, waist-to-height ratio, puberty development and age in the regression model. Obese children with high HOMA-IR presented a greater weight excess and significantly higher vascular markers, but TMAO levels did not differ significantly from the obese with HOMA-IR

Conclusion

Our study provides compelling evidence supporting the link between serum TMAO, obesity, and vascular damage in children. These findings highlight the importance of further research to unravel the underlying mechanisms of this connection.

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Key Words

• TMAO
• arterial stiffness
• atherosclerosis
• cardiovascular risk
• carotid intima-media thickness
• childhood obesity
• high blood pressure
• pulse wave velocity

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MESH Headings

• Adult
• Female
• Humans
• Child
• Pediatric Obesity/complications
• Carotid Intima-Media Thickness
• Vascular Stiffness/physiology
• Pulse Wave Analysis
• Acanthosis Nigricans
• Atherosclerosis/diagnosis
• Atherosclerosis/etiology
• Biomarkers

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Grants Collapse

Affiliation(s)

Monica Simina Mihuta Department of Doctoral Studies, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania Center of Molecular Research in Nephrology and Vascular Disease, Faculty of Medicine, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania
Corina Paul Department of Pediatrics, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania
Andreea Borlea Center of Molecular Research in Nephrology and Vascular Disease, Faculty of Medicine, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania 2nd Department of Internal Medicine, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania
Cristina Mihaela Roi Department of Doctoral Studies, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania Center of Molecular Research in Nephrology and Vascular Disease, Faculty of Medicine, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania
Denisa Pescari Department of Doctoral Studies, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania
Oana-Alexandra Velea-Barta 3rd Department of Odontotherapy and Endodontics, Faculty of Dental Medicine, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania
Ioana Mozos Department of Functional Sciences—Pathophysiology, Center for Translational Research and Systems Medicine, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania
Dana Stoian Center of Molecular Research in Nephrology and Vascular Disease, Faculty of Medicine, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania 2nd Department of Internal Medicine, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania

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Contribution of the microbiome for better phenotyping of people living with obesity

Obesity has reached epidemic proportion worldwide and in all ages. Available evidence points to a multifactorial pathogenesis involving gene predisposition and environmental factors. Gut microbiota plays a critical role as a major interface between external factors, i.e., diet, lifestyle, toxic chemicals, and internal mechanisms regulating energy and metabolic homeostasis, fat production and storage. A shift in microbiota composition is linked with overweight and obesity, with pathogenic mechanisms involving bacterial products and metabolites (mainly endocannabinoid-related mediators, short-chain fatty acids, bile acids, catabolites of tryptophan, lipopolysaccharides) and subsequent alterations in gut barrier, altered metabolic homeostasis, insulin resistance and chronic, low-grade inflammation. Although animal studies point to the links between an "obesogenic" microbiota and the development of different obesity phenotypes, the translational value of these results in humans is still limited by the heterogeneity among studies, the high variation of gut microbiota over time and the lack of robust longitudinal studies adequately considering inter-individual confounders. Nevertheless, available evidence underscores the existence of several genera predisposing to obesity or, conversely, to lean and metabolically health phenotype (e.g., Akkermansia muciniphila, species from genera Faecalibacterium, Alistipes, Roseburia). Further longitudinal studies using metagenomics, transcriptomics, proteomics, and metabolomics with exact characterization of confounders are needed in this field. Results must confirm that distinct genera and specific microbial-derived metabolites represent effective and precision interventions against overweight and obesity in the long-term.

Dynamic distribution of gut microbiota in posthatching chicks and its relationship with average daily gain

The colonization and development of gut microbiota are essential for the health and growth of chicks after hatching. However, the colonization and prevalence of gut microbiota have not been well characterized, and knowledge of which microbes and their relationship with average daily gain in chicks is still limited. This study characterized the dynamic succession of microbiota in the intestinal tract of chicks and investigated its relationship with daily weight gain. A total of 121 fecal samples across 7 time points from d 0 to 10 posthatching were collected from 19 chicks randomly selected from 1,950 chicks. Using 16S rRNA gene sequencing examined microbial composition of fecal samples. The observed species index of alpha diversity increased with age, gradually achieving stability at 3 d of age. The microbiota of chicks after hatching was primarily Clostridium_sensu_stricto_1 (34.49%), and its relative abundance diminishes with age. In contrast, Lactobacillus had a low relative abundance in the first 2 d after hatching and gradually increased with age. Predicted functional capacities found that the microbiota of early-stage posthatching (d 0 and 1 after hatching) was involved in metabolism, including amino acid metabolism, metabolism of cofactors and vitamins, and nitrogen metabolism. However, at the later stage posthatching (from d 3-10 after hatching), the intestinal microbial function was involved in carbohydrate metabolism, amino acid metabolism, cell growth and death, and methane metabolism. It was identified that 47 operational taxonomic units were associated with average daily gain of chicks, 12 of which were annotated with Lactobacillus and significantly positive associated with average daily gain. In addition, Clostridium_sensu_stricto_1 was significantly negatively associated with average daily gain. Taken together, we characterized the dynamic successions of intestinal microbiota in hatching chicks. The intestinal microbiota of chicks has an impact on the host average daily gain. Our findings should be instrumental in improving local chick production.

Inclusion of up to 20% Black Soldier Fly larvae meal in broiler chicken diet has a minor effect on caecal microbiota

Background

The Black Soldier Fly larvae (BSFL) are a source of nutrients and bioactive compounds in broiler diets. Some components of the BSFL may serve as a prebiotic or may impact the intestinal microbiota of the broilers by other modes of action, which in turn can affect the health and performance of broilers. Here, we investigate the impact of up to 20% BSFL in broiler diets on the diversity and composition of the broiler's microbiota.

Methods

Four hundred broilers were fed five iso-nutritious experimental diets with increasing levels of BSFL meal reaching 0%, 5%, 10%, 15%, 20% in the finisher diets. Eight caecal content samples coming from each of the eight replicates per treatment were collected at two time points (day 21 and day 42) for DNA extraction and sequencing of the V3-V4 regions using Illumina MiSeq 2 × 300 bp pair-end sequencing with 341f and 805r primers. Analysis of variance and Spearman's correlation were performed, while QIIME2, DADA2, and Calypso were used for data analysis.

Results

When broilers were 21 days of age, the abundance of two groups of sequence variants representing Enterococcus and unclassified Christensenellaceae was significantly lower (p-value = 0.048 and p-value = 0.025, respectively) in the 20% BSFL group compared to the 0% BSFL group. There was no relevant alteration in the microbiota diversity at that stage. On day 42, the Spearman correlation analysis demonstrated that the sequence variants representing the genus Coprococcus showed a negative relationship with the BSFL inclusion levels (p-value = 0.043). The sequence variants representing the genus Roseburia and Dehalobacterium demonstrated a positive relationship with the BSFL dietary inclusion (p-value = 0.0069 and p-value = 0.0034, respectively). There was a reduction in the dissimilarity index (ANOSIM) caused by the 20% BSFL dietary inclusion.

Conclusion

The addition of up to 20% BSFL in broiler diets did not affect the overall caeca microbiota diversity or composition at day 21. On day 42, there was a reduction in the beta diversity caused by the 20% BSFL dietary inclusion. The abundance of the bacterial group Roseburia was increased by the BSFL dietary inclusion, and it may be beneficial to broiler immunity and performance.

Causal relationships between the gut microbiome, blood lipids, and heart failure: a Mendelian randomization analysis

AIMS

Studies have linked gut microbiome and heart failure (HF). However, their causal relationships and potential mediating factors have not been well defined. To investigate the causal relationships between the gut microbiome and HF and the mediating effect of potential blood lipids by using genetics.

METHODS AND RESULTS

We performed a bidirectional and mediation Mendelian randomization (MR) study using summary statistics from the genome-wide association studies of gut microbial taxa (Dutch Microbiome Project, n = 7738), blood lipids (UK Biobank, n = 115 078), and a meta-analysis of HF (115 150 cases and 1550 331 controls). We applied the inverse-variance weighted estimation method as the primary method, with several other estimators as complementary methods. The multivariable MR approach based on Bayesian model averaging (MR-BMA) was used to prioritize the most likely causal lipids. Six microbial taxa are suggestively associated with HF causally. The most significant taxon was the species Bacteroides dorei [odds ratio = 1.059, 95% confidence interval (CI) = 1.022-1.097, P-value = 0.0017]. The MR-BMA analysis showed that apolipoprotein B (ApoB) was the most likely causal lipid for HF (the marginal inclusion probability = 0.717, P-value = 0.005). The mediation MR analysis showed that ApoB mediated the causal effects of species B. dorei on HF (proportion mediated = 10.1%, 95% CI = 0.2-21.6%, P-value = 0.031).

CONCLUSION

The study suggested a causal relationship between specific gut microbial taxa and HF and that ApoB might mediate this relationship as the primary lipid determinant of HF.

Impact of clozapine monotherapy on gut microbiota and metabolism in people with schizophrenia

Background

Clozapine is considered one of the most effective antipsychotic drugs, but it is most likely to cause metabolic abnormalities. Researchers have studied the causes of metabolic abnormalities caused by clozapine from multiple perspectives, but the reasons remain unclear.

Purpose

Characterize the gut microbiota of people with schizophrenia taking clozapine, exploring the association between gut microbiota and glucose lipid metabolic markers in schizophrenia patients taking clozapine.

Research design

Sixty-one long-term inpatients with schizophrenia in clozapine monotherapy were selected as study subjects. We got four subgroups by sex and the presence of metabolic syndrome.

Data analysis

16s analysis technology was applied at the genus level to determine the classification of gut microbiota. Then we compared the characteristics of gut microbiota and the association of gut microbiota with glucose lipid metabolic markers in each group.

Findings

We found differences in the diversity of gut microbiota among groups. The association between gut microbiota and glucose lipid metabolic markers was complicated. Gender was an important differentiating factor. Oscillibacter has a low abundance. However, it was the only genus associated with glycemic or lipids in each group. Among metabolic syndromes, Gemmiger was positively correlated with most lipids in females but negatively correlated in males, showing gender differences. In female non-metabolic syndromes, Bifidobacterium lost its probiotic character; instead, showing pathogenicity, which has strong positive correlations with fasting blood glucose and low-density lipoprotein but negative correlations with Apolipoprotein A1. Maybe schizophrenia, taking clozapine, and gender factors influenced the gut microbiota, which complicated our findings. The significance of the results remains to be determined by in-depth studies.

Combined effect of microbially derived cecal SCFA and host genetics on feed efficiency in broiler chickens

BACKGROUND

Improving feed efficiency is the most important goal for modern animal production. The regulatory mechanisms of controlling feed efficiency traits are extremely complex and include the functions related to host genetics and gut microbiota. Short-chain fatty acids (SCFAs), as significant metabolites of microbiota, could be used to refine the combined effect of host genetics and gut microbiota. However, the association of SCFAs with the gut microbiota and host genetics for regulating feed efficiency is far from understood.

RESULTS

In this study, 464 broilers were housed for RFI measuring and examining the host genome sequence. And 300 broilers were examined for cecal microbial data and SCFA concentration. Genome-wide association studies (GWAS) showed that four out of seven SCFAs had significant associations with genome variants. One locus (chr4: 29414391-29417189), located near or inside the genes MAML3, SETD7, and MGST2, was significantly associated with propionate and had a modest effect on feed efficiency traits and the microbiota. The genetic effect of the top SNP explained 8.43% variance of propionate. Individuals with genotype AA had significantly different propionate concentrations (0.074 vs. 0.131 μg/mg), feed efficiency (FCR: 1.658 vs. 1.685), and relative abundance of 14 taxa compared to those with the GG genotype. Christensenellaceae and Christensenellaceae_R-7_group were associated with feed efficiency, propionate concentration, the top SNP genotypes, and lipid metabolism. Individuals with a higher cecal abundance of these taxa showed better feed efficiency and lower concentrations of caecal SCFAs.

CONCLUSION

Our study provides strong evidence of the pathway that host genome variants affect the cecal SCFA by influencing caecal microbiota and then regulating feed efficiency. The cecal taxa Christensenellaceae and Christensenellaceae_R-7_group were identified as representative taxa contributing to the combined effect of host genetics and SCFAs on chicken feed efficiency. These findings provided strong evidence of the combined effect of host genetics and gut microbial SCFAs in regulating feed efficiency traits. Video Abstract.

Dissecting Causal Relationships Between Gut Microbiota, Blood Metabolites, and Stroke: A Mendelian Randomization Study

BACKGROUND AND PURPOSE

We investigated the causal relationships between the gut microbiota (GM), stroke, and potential metabolite mediators using Mendelian randomization (MR).

METHODS

We leveraged the summary statistics of GM (n=18,340 in the MiBioGen consortium), blood metabolites (n=115,078 in the UK Biobank), and stroke (cases n=60,176 and controls n=1,310,725 in the Global Biobank Meta-Analysis Initiative) from the largest genome-wide association studies to date. We performed bidirectional MR analyses to explore the causal relationships between the GM and stroke, and two mediation analyses, two-step MR and multivariable MR, to discover potential mediating metabolites.

RESULTS

Ten taxa were causally associated with stroke, and stroke led to changes in 27 taxa. In the two-step MR, Bifidobacteriales order, Bifidobacteriaceae family, Desulfovibrio genus, apolipoprotein A1 (ApoA1), phospholipids in high-density lipoprotein (HDL_PL), and the ratio of apolipoprotein B to ApoA1 (ApoB/ApoA1) were causally associated with stroke (all P<0.044). The causal associations between Bifidobacteriales order, Bifidobacteriaceae family and stroke were validated using the weighted median method in an independent cohort. The three GM taxa were all positively associated with ApoA1 and HDL_PL, whereas Desulfovibrio genus was negatively associated with ApoB/ApoA1 (all P<0.010). Additionally, the causal associations between the three GM taxa and ApoA1 remained significant after correcting for the false discovery rate (all q-values <0.027). Multivariable MR showed that the associations between Bifidobacteriales order, Bifidobacteriaceae family and stroke were mediated by ApoA1 and HDL_PL, each accounting for 6.5% (P=0.028) and 4.6% (P=0.033); the association between Desulfovibrio genus and stroke was mediated by ApoA1, HDL_PL, and ApoB/ApoA1, with mediated proportions of 7.6% (P=0.019), 4.2% (P=0.035), and 9.1% (P=0.013), respectively.

CONCLUSION

The current MR study provides evidence supporting the causal relationships between several specific GM taxa and stroke and potential mediating metabolites.

Heritability and recursive influence of host genetics on the rumen microbiota drive body weight variance in male Hu sheep lambs

BACKGROUND

Heritable rumen microbiota is an important modulator of ruminant growth performance. However, no information exists to date on host genetics-rumen microbiota interactions and their association with phenotype in sheep. To solve this, we curated and analyzed whole-genome resequencing genotypes, 16S rumen-microbiota data, and longitudinal body weight (BW) phenotypes from 1150 sheep.

RESULTS

A variance component model indicated significant heritability of rumen microbial community diversity. Genome-wide association studies (GWAS) using microbial features as traits identified 411 loci-taxon significant associations (P < 10-8). We found a heritability of 39% for 180-day-old BW, while also the rumen microbiota likely played a significant role, explaining that 20% of the phenotypic variation. Microbiota-wide association studies (MWAS) and GWAS identified four marker genera (Bonferroni corrected P < 0.05) and five novel genetic variants (P < 10-8) that were significantly associated with BW. Integrative analysis identified the mediating role of marker genera in genotype influencing phenotype and unravelled that the same genetic markers have direct and indirect effects on sheep weight.

CONCLUSIONS

This study reveals a reciprocal interplay among host genetic variations, the rumen microbiota and the body weight traits of sheep. The information obtained provide insights into the diverse microbiota characteristics of rumen and may help in designing precision microbiota management strategies for controlling and manipulating sheep rumen microbiota to increase productivity. Video Abstract.

Multi-omics reveal microbial determinants impacting the treatment outcome of antidepressants in major depressive disorder

BACKGROUND

There is a growing body of evidence suggesting that disturbance of the gut-brain axis may be one of the potential causes of major depressive disorder (MDD). However, the effects of antidepressants on the gut microbiota, and the role of gut microbiota in influencing antidepressant efficacy are still not fully understood.

RESULTS

To address this knowledge gap, a multi-omics study was undertaken involving 110 MDD patients treated with escitalopram (ESC) for a period of 12 weeks. This study was conducted within a cohort and compared to a reference group of 166 healthy individuals. It was found that ESC ameliorated abnormal blood metabolism by upregulating MDD-depleted amino acids and downregulating MDD-enriched fatty acids. On the other hand, the use of ESC showed a relatively weak inhibitory effect on the gut microbiota, leading to a reduction in microbial richness and functions. Machine learning-based multi-omics integrative analysis revealed that gut microbiota contributed to the changes in plasma metabolites and was associated with several amino acids such as tryptophan and its gut microbiota-derived metabolite, indole-3-propionic acid (I3PA). Notably, a significant correlation was observed between the baseline microbial richness and clinical remission at week 12. Compared to non-remitters, individuals who achieved remission had a higher baseline microbial richness, a lower dysbiosis score, and a more complex and well-organized community structure and bacterial networks within their microbiota. These findings indicate a more resilient microbiota community in remitters. Furthermore, we also demonstrated that it was not the composition of the gut microbiota itself, but rather the presence of sporulation genes at baseline that could predict the likelihood of clinical remission following ESC treatment. The predictive model based on these genes revealed an area under the curve (AUC) performance metric of 0.71.

CONCLUSION

This study provides valuable insights into the role of the gut microbiota in the mechanism of ESC treatment efficacy for patients with MDD. The findings represent a significant advancement in understanding the intricate relationship among antidepressants, gut microbiota, and the blood metabolome. Additionally, this study offers a microbiota-centered perspective that can potentially improve antidepressant efficacy in clinical practice. By shedding light on the interplay between these factors, this research contributes to our broader understanding of the complex mechanisms underlying the treatment of MDD and opens new avenues for optimizing therapeutic approaches. Video Abstract.

Emodin Inhibited Pathological Cardiac Hypertrophy in Response to Angiotensin-Induced Hypertension and Altered the Gut Microbiome

OBJECTIVE

Evidence suggests that food bioactives affect the epigenome to prevent pathological cardiac hypertrophy. Recently, we showed that emodin, an anthraquinone, attenuated pathological cardiac hypertrophy and histone deacetylase (HDAC) activity. However, we only examined the cardioprotective effects of emodin's parent compound and not those of emodin metabolites or of emodin-gut microbiome interactions. The microbiome has emerged as a key player in chronic diseases such as metabolic and cardiac disease. Thus, we hypothesized that emodin could reverse hypertension-induced changes in microbial communities.

METHODS

Normo- and hypertensive (angiotensin II) C57/BL6 female mice were randomly assigned to receive a vehicle (Veh; DMSO:PEG 1:1) or emodin (Emod; 30 mg/kg) for 14 days. Body weights were collected pre- and post-treatment, and blood pressure was assessed via tail cuff. At the study's end, the mice were euthanized and assessed for their heart weights. In addition, stool samples and cecal contents were collected to elucidate changes in the microbial populations using 16S rRNA sequencing. Lastly, the tissue was lysed, and RNA was isolated for qPCR. One-way ANOVA with Tukey's post hoc test was performed unless otherwise specified, and p < 0.05 was considered significant.

RESULTS

Emodin significantly attenuated cardiac hypertrophy in the female mice. No significant changes were observed in body weight or systolic blood pressure in response to hypertension or emodin. Lastly, analysis suggests that hypertension altered the microbiome in the cecum and cecal content, with additional evidence to support that emodin affects gut microbiota in the feces and colon.

CONCLUSIONS

Our data demonstrate that emodin attenuates pathological hypertrophy in female mice. Future research is needed to dissect if changes in the microbiome contributes to emodin-mediated attenuation in cardiac remodeling.

Synergy and oxygen adaptation for development of next-generation probiotics

The human gut microbiota has gained interest as an environmental factor that may contribute to health or disease1. The development of next-generation probiotics is a promising strategy to modulate the gut microbiota and improve human health; however, several key candidate next-generation probiotics are strictly anaerobic2 and may require synergy with other bacteria for optimal growth. Faecalibacterium prausnitzii is a highly prevalent and abundant human gut bacterium associated with human health, but it has not yet been developed into probiotic formulations2. Here we describe the co-isolation of F. prausnitzii and Desulfovibrio piger, a sulfate-reducing bacterium, and their cross-feeding for growth and butyrate production. To produce a next-generation probiotic formulation, we adapted F. prausnitzii to tolerate oxygen exposure, and, in proof-of-concept studies, we demonstrate that the symbiotic product is tolerated by mice and humans (ClinicalTrials.gov identifier: NCT03728868 ) and is detected in the human gut in a subset of study participants. Our study describes a technology for the production of next-generation probiotics based on the adaptation of strictly anaerobic bacteria to tolerate oxygen exposures without a reduction in potential beneficial properties. Our technology may be used for the development of other strictly anaerobic strains as next-generation probiotics.

LDL cholesterol-lowering effect of Daeshiho-tang in patients with dyslipidemia: A pilot randomized, double-blind, placebo-controlled trial

Dyslipidemia, a major risk factor for atherosclerotic cardiovascular disease, can be prevented by lowering low-density lipoprotein cholesterol (LDL-C) levels. The lipid improvement effects of Daeshiho-tang (DSHT), a herbal formula, have been proven through various preclinical studies based on anti-obesity and anti-inflammatory properties, however, clinical trials were few. This preliminary study aimed to assess the lipid-lowering effect of DSHT in patients with dyslipidemia and examine its safety profile. The study was a randomized, double-blind, placebo-controlled trial. The trial included 60 patients with untreated dyslipidemia: total cholesterol (TC) > 200 mg/dL, triglyceride (TG) > 150 mg/dL, LDL-C >130 mg/dL, or high-density lipoprotein cholesterol (HDL-C) <40 mg/dL. Participants (mean age, 44.7 ± 13.7 years) consumed DSHT extract or an equivalent placebo at a dose of 3 g, thrice a day for 8 weeks. Participants underwent blood tests assessing serum lipid and apolipoprotein (apo) levels, including LDL-C, HDL-C, TC, TG, apoA1, and apoB, at baseline and 4 and 8 weeks. Levels of biochemical safety markers, including AST, ALT, GGT, creatinine, and eGFR, were assessed throughout the study. Between the two groups, significant differences were observed in the changes of LDL-C, TC, and apoB concentrations from baseline to post-intervention. Compared with the placebo group, DSHT-administered participants showed significantly reduced LDL-C by 14.0 ± 4.66 mg/dL (p < 0.01), TC by 13.7 ± 4.73 mg/dL (p < 0.01) and apolipoprotein-B by 7.03 ± 3.23 mg/dL (p < 0.05). No significant changes were observed in the safety biochemical parameters in either group. DSHT treatment for 8 weeks improved LDL-C levels and reduced apoB concentrations without severe adverse events.

Uncovering the Gut-Liver Axis Biomarkers for Predicting Metabolic Burden in Mice

Western diet (WD) intake, aging, and inactivation of farnesoid X receptor (FXR) are risk factors for metabolic and chronic inflammation-related health issues ranging from metabolic dysfunction-associated steatotic liver disease (MASLD) to dementia. The progression of MASLD can be escalated when those risks are combined. Inactivation of FXR, the receptor for bile acid (BA), is cancer prone in both humans and mice. The current study used multi-omics including hepatic transcripts, liver, serum, and urine metabolites, hepatic BAs, as well as gut microbiota from mouse models to classify those risks using machine learning. A linear support vector machine with K-fold cross-validation was used for classification and feature selection. We have identified that increased urine sucrose alone achieved 91% accuracy in predicting WD intake. Hepatic lithocholic acid and serum pyruvate had 100% and 95% accuracy, respectively, to classify age. Urine metabolites (decreased creatinine and taurine as well as increased succinate) or increased gut bacteria (Dorea, Dehalobacterium, and Oscillospira) could predict FXR deactivation with greater than 90% accuracy. Human disease relevance is partly revealed using the metabolite-disease interaction network. Transcriptomics data were also compared with the human liver disease datasets. WD-reduced hepatic Cyp39a1 (cytochrome P450 family 39 subfamily a member 1) and increased Gramd1b (GRAM domain containing 1B) were also changed in human liver cancer and metabolic liver disease, respectively. Together, our data contribute to the identification of noninvasive biomarkers within the gut-liver axis to predict metabolic status.