Maternal consumption of l-malic acid enriched diets improves antioxidant capacity and glucose metabolism in offspring by regulating the gut microbiota

Maternal consumption of urbanized diet compromises early-life health in association with gut microbiota

Urbanization has significantly transformed dietary habits worldwide, contributing to a globally increased burden of non-communicable diseases and altered gut microbiota landscape. However, it is often overlooked that the adverse effects of these dietary changes can be transmitted from the mother to offspring during early developmental stages, subsequently influencing the predisposition to various diseases later in life. This review aims to delineate the detrimental effects of maternal urban-lifestyle diet (urbanized diet) on early-life health and gut microbiota assembly, provide mechanistic insights on how urbanized diet mediates mother-to-offspring transfer of bioactive substances in both intrauterine and extrauterine and thus affects fetal and neonatal development. Moreover, we also further propose a framework for developing microbiome-targeted precision nutrition and diet strategies specifically for pregnant and lactating women. The establishment of such knowledge can help develop proactive preventive measures from the beginning of life, ultimately reducing the long-term risk of disease and improving public health outcomes.

Associations of Ruminal Microbiota with Susceptibility to subacute Ruminal Acidosis in Dairy Goats

Long-term feeding of high-concentrate diets (HCD) to ruminants often leads to subacute ruminal acidosis (SARA). The fact that some ruminants adapt to HCD without developing SARA suggests that the ruminal microbiota communities may play a role in the susceptibility to this disorder. To address this hypothesis, 20 dairy goats were fed an HCD consisting of 30% forage and 70% concentrate for 10 weeks. The dairy goats were divided into a SARA susceptible group (SS, pH < 5.8 for more than 3 hours within 12 hours) and a SARA tolerant group (ST, pH < 5.8 for not more than 3 hours within 12 hours) according to ruminal fluid pH. At 0 and 10 weeks after feeding with HCD, blood samples were collected via the jugular vein using a vacutainer to assess the levels of white blood cells, neutrophils, and lymphocytes. Meanwhile, milk samples were collected to measure milk composition. In addition, ruminal fluid was collected via a gastric tube at 0 and 10 weeks of feeding the experimental diets via gastric tube and the ruminal microbiota of SS and ST dairy goats were analyzed. The results indicated that feeding with HCD led to greater levels of white blood cells, neutrophils, creatinine, and urea nitrogen, and lower concentrations of milk fat. Further, levels of white blood cells and neutrophils were greater in SS compared with ST goats. The 16S rRNA sequencing analysis revealed that the diversity and abundance of the ruminal bacterial community was lower in SS compared to ST goats. Furthermore, the relative abundance of norank_f_F082, norank_f_Bifidobacteriaceae, and the genus Ruminococcus was higher in the SS group. These microorganisms are important for the digestion of non-structural carbohydrates and the production of volatile fatty acids (VFA). The initial ruminal microbiota composition analysis revealed that Rikenellaceae_RC9_gut_group was greater in ST goats, both before and after feeding HCD. By promoting carbohydrate metabolism in the rumen, the data suggest that the increased abundance of norank_f_F082, Ruminococcus and UCG-004 may lead to the production of metabolites that increase susceptibility to SARA when fed HCD. Enrichment of ruminal bacteria such as Rikenellaceae_RC9_gut_group may reduce susceptibility to SARA in HCD diets. Overall, manipulation of the ruminal microbiota may be a novel approach to prevent the development of SARA in ruminants.

Intestinal microbiota-derived d-(+)-malic acid promotes pBD1 expression via p-p38/ATF1 signaling pathway to maintain porcine intestinal health

This study aims to identify nutrients that enhance the expression of host defense peptides (HDPs) and to evaluate their application effects and regulatory mechanisms, thereby advancing the exploring of nutritional regulation of HDPs. To achieve this, we constructed 16 stable fluorescent reporter porcine epithelial cell lines, driven by promoters targeting eight porcine intestinal HDPs genes, using IPEC-1 and IPEC-J2 cells. Through untargeted metabolomics sequencing and high-throughput screening, 15 metabolites were identified as potential enhancers of pBD1 expression, with d-(+)-malic acid (DMA) emerged as the most effective candidate. Transcriptomic and western blot analysis suggested that DMA enhances pBD1 expression primarily via the p-p38/ATF1 signaling pathways. Functional studies demonstrated that DMA significantly improved intestinal barrier integrity and alleviated intestinal damage. Overall, this work successfully established promoter-driven fluorescent reporter cell lines and identified microbiota-derived metabolites enhancing pBD1 expression, such as DMA, as promising alternatives to antibiotics for maintaining porcine intestinal health.

Impacts and mechanism of liver-specific knockout of selenoprotein I on hepatic phospholipid metabolism, selenogenome expression, redox status, and resistance to CCl4 toxicity

Selenoprotein I (SELENOI) was known initially as ethanolamine phosphotransferase 1 (EPT1) and later as a selenoprotein. Because global knockout of Selenoi in mice is embryonically lethal, we generated liver-specific Selenoi knockout (cKO) mice to reveal functions and mechanism of SELENOI in the liver. Compared with control mice, cKO mice (8 weeks old) had no differences in body weight, glucose metabolism, energy expenditure, overall health status, or liver histology. However, these mice had lower (P < 0.05) mRNA levels of 13 selenoprotein genes, contents of Se, GSH, and T-AOC (12-40%), and activities of antioxidant enzymes (17-51%), but higher (P < 0.05) mRNA levels of oxidative stress-related genes (34%-46%) in the liver than the control mice. They had a higher (P < 0.05) ratio of phosphatidylcholine (PC) to phosphatidylethanolamine (PE) due to increases of the former and decreases of the latter, altered PE and PC constituents such as n-6/n-3 PUFA ratios, and elevated mRNA levels (95%-2-fold, P < 0.05) of lipolysis genes, compared with the control mice. The knockout attenuated hepatic injury and fibrosis induced by 14 intraperitoneal injections of CCl4 (0.5 mL/kg). The protection was associated with adaptive cytoprotective mechanisms induced by the overall decline of redox status mediated by SELENOI as a selenoprotein and activations of PPAR signaling, fatty acid desaturase 2 (FADS2), glutathione S-transferase, and lipid peroxide hydrolysis through modulating biosynthesis and(or) constituents of PC, PE, and n-6/n-3 PUFAs mediated by SELENOI as EPT1. Inhibition of FADS2 in CCl4-treated cKO hepatocytes partially removed the protection by the knockout. In conclusion, hepatic SELENOI expression was not essential for survival, but served as a multifunctional regulator of hepatic selenogenome expression, Se metabolism, redox status, biosyntheses and profiles of PC and PE, and resistance to CCI4.

A new strategy for the fermentation of Massa Medicata Fermentata by combining multiple strains of fermentation and their fermentation mechanisms

To address the quality instability of the traditional fermentation process of Massa Medicata Fermentata (LSQ), we designed an innovation strategy for dual-strain co-fermentation LSQ. Rhizopus arrhizus, Bacillus velezensis, Bacillus subtills, and Bacillus cereus were selected as the fermentation strains for the LSQ. After dual-strain co-fermentation, its pro-digestive enzymes and anti-inflammatory activities were significantly enhanced. Particularly, R. arrhizus/B. subtills fermentation group showed the prominent promotion of the enzymatic activities of amyloglucosidase, cellulase and trypsin, with AC200 values < 1.00 and Max fold increase values of 27.39 ± 0.22, 25.39 ± 0.87 and 48.07 ± 1.84, respectively, and anti-inflammatory activity with an IC50 value of 2.35 ± 0.18 mg/mL. Based on the correlation analysis of differential metabolic profiles and activities, the key pharmacodynamic metabolites were analyzed and validated, such as levomycetin succinatea, β-citrylglutamate, D-glucosaminic acid, nikkomycin and fucose 1-phosphate. Among them, D-glucosaminic acid was positively correlated with the promoting activity of amyloglucosidase, cellulose, enzyme trypsin, pepsin, and the inhibitory activity of NO production, and fucose 1-phosphate and nikkomycin had the prominently positive correlation with the promoting activity of pepsin (p < 0.01). In addition, the docking scores between them and digestive enzyme proteins were all < - 5. A new strategy involving the dual-strain fermentation of LSQ was investigated, and clarified the LSQ fermentation strain-constituent-pharmacological activity correlations, which provides a valuable reference for delving into the LSQ fermentation mechanism.

Dietary Fiber Intake Improves Osteoporosis Caused by Chronic Lead Exposure by Restoring the Gut-Bone Axis

Background: Lead (Pb), a pervasive environmental toxicant with specific toxicity to bone, has been recognized as a significant etiological factor in the pathogenesis of osteoporosis. While dietary fiber (DF) demonstrates anti-osteoporotic potential, its protective role against Pb-induced bone loss remains unexplored. Methods: This study analyzed the association between dietary fiber, blood lead, and osteoporosis based on the NHANES database, and validated it by constructing a lead exposed mouse model. Micro CT was used to evaluate bone microstructure, ELISA was used to detect bone markers, q-PCR/Western blot was used to measure intestinal tight junction protein, flow cytometry was used to analyze Treg cells in colon/bone tissue, GC-MS was used to detect short chain fatty acids, and 16S rRNA sequencing was used to analyze changes in gut microbiota. The regulatory mechanism of dietary fiber on bone metabolism and intestinal barrier in lead exposed mice was systematically evaluated. Results: Based on NHANES data analysis, it was found that dietary fiber can reduce the risk of osteoporosis in lead exposed populations. Animal experiments have shown that dietary fiber intervention significantly increases bone density, improves bone microstructure and metabolic indicators, repairs intestinal barrier damage caused by lead exposure, and regulates immune balance in lead exposed mice. At the same time, it promotes the generation of short chain fatty acids and the proliferation of beneficial gut microbiota. Conclusions: These findings indicate that DF mitigates Pb-induced osteoporosis through gut barrier restoration, SCFA-mediated immunomodulation, and microbiota-driven Treg cell expansion along the gut-bone axis.

Changes in the metabolome, lipidomein, and gut microbiota in Behçet's disease

Backgrounds

There is growing evidence that autoimmune illnesses are associated with the metabolome and microbiota. Because Behçet's disease (BD) is not often diagnosed as a systemic disorder, the aim of this research was to investigate changes in gut flora and metabolites in BD patients.

Methods

We used 16S rRNA gut microbiota gene sequencing and UPLC-QTOF-MS analysis to gather stool and serum samples from 12 age-matched healthy controls and 17 BD patients. The correlation between changes in gut microbiota and metabolites was then further analyzed.

Results

In contrast to healthy controls, our investigation revealed significant changes in the makeup of gut flora in BD patients. In particular, we observed that in the BD group, there was a large drop in clostridia but a noticeable rise in γ-proteobacteria and betaproteobacteria. The serum metabolomics profiles of BD patients and healthy controls may be reliably differentiated using unsupervised principal component analysis (PCA). Several metabolites, including L-phenylalaine, tricarballylic acid, beta-leucine, ketoleucine, ascorbic acid, l-glutamic acid, l-malic acid, d-glucopyranuronic acid, and methyl acetoacetate, were found to have differential expression between BD patients and healthy controls. All of these metabolites were significantly lower in the BD group. Furthermore, we discovered strong associations between the detected metabolites such as tricarballylic acid, L-malic acid, D-glucopyranuronic acid with certain microbial families, such Prevotellaceae and Alcaligenaceae.

Conclusion

Patients with BD were found to have significant changes in the makeup of their gut flora and metabolites.

Optimized oxygen therapy improves sleep deprivation-induced cardiac dysfunction through gut microbiota

Adequate sleep is of paramount importance for relieving stress and restoring mental vigor. However, the adverse physiological and pathological responses resulting from sleep insufficiency or sleep deprivation (SD) are becoming increasingly prevalent. Currently, the impact of sleep deficiency on gut microbiota and microbiota-associated human diseases, especially cardiac diseases, remains controversial. Here, we employed the following methods: constructed an experimental sleep-deprivation model in mice; conducted 16S rRNA sequencing to investigate the changes in gut microbiota; through fecal microbiota transplantation (FMT) experiments, transplanted fecal microbiota from sleep-deprived mice to other mice; established an environment with a 30% oxygen concentration to explore the therapeutic effects of oxygen therapy on gut microbiota-associated cardiac fibrosis and dysfunction; and utilized transcriptome data to study the underlying mechanisms of oxygen therapy. The results revealed that: sleep-deprived mice exhibited weakness, depression-like behaviors, and dysfunction in multiple organs. Pathogenic cardiac hypertrophy and fibrosis occurred in sleep-deprived mice, accompanied by poor ejection fraction and fractional shortening. 16S rRNA sequencing indicated that sleep deprivation induced pathogenic effects on gut microbiota, and similar phenomena were also observed in mice that received fecal microbiota from sleep-deprived mice in the FMT experiments. The environment with a 30% oxygen concentration effectively alleviated the pathological impacts on cardiac function. Transcriptome data showed that oxygen therapy targeted several hypoxia-dependent pathways and inhibited the production of cardiac collagen. In conclusion, these results demonstrate the significance of sufficient sleep for gut microbiota and may represent a potential therapeutic strategy, where the oxygen environment exerts a protective effect on insomniacs through gut microbiota.

Malic enzyme 3 mediated the effects of malic acid on intestinal redox status and feed efficiency in broilers

BACKGROUND

Intestinal oxidative stress serves as an endogenous host defense against the gut microbiota by increasing energy expenditure and therefore decreasing feed efficiency (FE). Several systems coordinately regulate redox balance, including the mitochondrial respiratory chain, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and different antioxidants. However, it remains unclear which redox balance compartments in the intestine are crucial for determining FE.

RESULTS

In this study, we first screened the key targets of different metabolites and redox balance-related gene expression in broiler ceca. We then constructed a mouse colitis model to explore malic acid (MA) ability to alleviate intestinal inflammation. We further used controlled release technology to coat MA and investigated its effects on the intestinal redox status and FE in vivo. Finally, we examined the underlying mechanism by which MA modulated redox status using a porcine intestinal epithelial cell jejunum 2 (IPEC-J2) cell model in vitro. Our results demonstrated that the MA/malic enzyme 3 (ME3) pathway may play an important role in reducing oxidative stress in the broiler cecum. In addition, colon infusion of MA attenuated inflammatory phenotypes in the dextran sulfate sodium salt (DSS) induced mouse colitis model. Then, dietary supplementation with controlled-release MA pellet (MAP) reduced the feed to gain (F/G) ratio and promoted chicken growth, with reduced oxidative stress and increased bacterial diversity. Finally, the in vitro IPEC-J2 cell model revealed that ME3 mediated the effect of MA on cellular oxidative stress.

CONCLUSION

In summary, our study firstly revealed the important role of the MA/ME3 system in the hindgut of broiler chickens for improving intestinal health and FE, which may also be crucial for the implications of colon inflammation associated diseases.

Phytochemical Compounds from Laelia furfuracea and Their Antioxidant and Anti-Inflammatory Activities

Laelia furfuracea is an orchid endemic to Oaxaca, Mexico, used for the treatment of cough and has anticoagulant activity. We aimed to evaluate the anti-inflammatory and antioxidant activity of the hydroethanolic extract of L. furfuracea leaves and identify its phytochemical compounds. The leaf material was subjected to solid-liquid extraction. Compounds were identified by UPLC-ESI-qTOF-MS/MS. The Folin-Ciocalteu and aluminum trichloride methods were used to quantify phenols and flavonoids, respectively. The DPPH method was used to determine the antioxidant activity. The anti-inflammatory activity was evaluated in a model of carrageenan-induced plantar edema induced in Wistar rats. Compounds tentatively identified in L. furfuracea leaves were malic, citric, succinic, hydroximethylglutaric, azelaic, eucomic, and protocatechuic acids, saponarin, luteolin-7,3'-di-O-glucoside, isoorientin, and vitexin. The contents of total phenols and flavonoids and antioxidant activity were 394.7 ± 0.1 mg EqAG/g, 129.9 ± 0.005 mg EqQ/g, and 84.6 ± 1.4%, respectively. The anti-inflammatory effect of the extract was dose-dependent, where 1000 µg/paw presented a 43.4% reduction in inflammation, similar to naproxen. The anti-inflammatory and antioxidant effect of the hydroethanolic extract of Laelia furfuracea leaves was demonstrated. This effect may be due to the synergy between its compounds. This orchid is a potential candidate for future pharmacological research due to its anti-inflammatory activity.

Maternal Roughage Sources Influence the Gastrointestinal Development of Goat Kids by Modulating the Colonization of Gastrointestinal Microbiota

During pregnancy and lactation, maternal nutrition is linked to the full development of offspring and may have long-term or lifelong effects. However, the influence of the doe's diet on the gastrointestinal (GI) tract of young kids remains largely unexplored. Therefore, we investigated the effects of doe roughage sources (alfalfa hay, AH, or corn straw, CS) during pregnancy and lactation on kid growth, GI morphology, barrier function, metabolism, immunity, and microbiome composition. The results indicate that, compared with the CS group, does fed an AH diet had significantly higher feed intake (p < 0.01). However, CS-fed does exhibited higher neutral detergent fiber (NDF) digestibility (p < 0.05). There were no significant differences in animal (doe or kid) weight among the groups (p > 0.05). In the rumen of goat kids, the AH group exhibited a higher papillae width and increased levels of interleukin-10 (IL-10) compared with the CS group (p < 0.05). In the jejunum of goat kids, the AH group showed a higher villus-height-to-crypt-depth (VH/CD) ratio, as well as elevated levels of secretory immunoglobulin A (SIgA), immunoglobulin G (IgG), IL-10, acetate, and total volatile fatty acids (TVFAs), when compared with the CS group (p < 0.05). Transcriptome analysis revealed that the source of roughage in does was associated with changes in the GI transcriptome of the kids. Differentially expressed genes (DEGs) in the rumen were mainly associated with tissue development and immune regulation, while the DEGs in the jejunum were mainly associated with the regulation of transferase activity. Spearman correlation analyses indicated significant associations between GI DEGs and phenotypic indicators related to GI development, immunity, and metabolism. LEfSe analysis identified 14 rumen microbial biomarkers and 6 jejunum microbial biomarkers. Notably, these microorganisms were also enriched in the rumen or day 28 milk of the does. Further microbial composition analysis revealed significant correlations between the rumen and milk microbiomes of does and the rumen or jejunum microbiomes of kids. Association analyses indicated that microbial biomarkers interact with host genes, thereby affecting the development and function of the GI system. Additionally, correlation analyses revealed significant association between milk metabolites and the rumen and jejunum microbiomes of kids. This study demonstrated that maternal diet significantly influences the development of microbial ecosystems in offspring by modulating microbial communities and metabolite composition. The early colonization of GI microorganisms is crucial for the structural development, barrier function, immune capacity, and microbial metabolic activity of the GI system.

Oxidative stress controls lncRNA-mediated sow granulosa cell functions in a FoxO1-dependent manner

BACKGROUND

Oxidative stress (OS) is involved in low female fertility by altering multi-omics such as the transcriptome, miRome, and lncRNome in follicular cells and follicular fluid. However, the mechanism by which OS affects multi-omics dynamics remains largely unknown. Here, we report that OS induces lncRNome dynamics in sow granulosa cells (sGCs), which is partially dependent on the transcription factor activity of its effector, FoxO1.

RESULTS

A total of 2,283 putative FoxO recognition elements (FREs) were identified in the promoters of 394 lncRNAs, accounting for 91.20% (394/432) of the lncRNAs regulated by OS. ChIP and reporter assays showed that the effector FoxO1 mediated OS regulation of lncRNA transcription in a transcription factor activity-dependent manner. In sGCs, OS induces the transcription and function (e.g., apoptosis) of NORSF (non-coding RNA involved in sow fertility), a nuclear lncRNA involved in sGC function via FoxO1. Furthermore, FoxO1 has been identified as a transcriptional activator of NORSF in sGCs that interacts with the FRE motif of its promoter. Meanwhile, OS downregulates the transcription of CYP19A1, which encodes an essential enzyme for estrogen synthesis and 17β-estradiol (E2) release by sGCs via the FoxO1 and NORSF axis. Phenotypically, dysregulation of NORSF transcription caused by 2 novel adjacent transitions in the promoter leads to decreased sow fertility.

CONCLUSION

These results suggest a model of OS-stimulated lncRNome dynamics in sGCs and a new signaling pathway of OS that influences sGC function and sow fertility.

Mixed Th1/Th2/Th17 Responses Induced by Plant Oil Adjuvant-Based B. bronchiseptica Vaccine in Mice, with Mechanisms Unraveled by RNA-Seq, 16S rRNA and Metabolomics

BACKGROUND/OBJECTIVES

The current Bordetella bronchiseptica (Bb) vaccine, when adjuvanted with alum, does not elicit adequate robust cellular immunity or effective antibody defense against Bb attacks. Unfortunately, antibiotic treatment generally represents an ineffective strategy due to the development of resistance against a broad range of antibiotics.

METHODS

The present study was designed to investigate the immune response, protective capabilities and underlying mechanisms of a plant oil-based adjuvant E515 formulated with inactivated Bb antigen as a potential vaccine candidate against Bordetella bronchiseptica.

RESULTS

Immunization studies revealed that a combination of SO, VE and GS (E515) exhibited a good synergistic adjuvant effect. The E515 adjuvanted Bb vaccine was proven to be highly efficacious and induced a mixed Th1/Th2/Th17 immune response in mice, leading to a significant increase in Bb-specific IgG, IgG1 and IgG2a antibodies, proliferative lymphocyte responses and cytokine levels (by lymphocytes and serum) and effectively induced responses by CD4+ TE, TM cells and B cells. The E515 adjuvant significantly enhanced the immune protection provided by the Bb vaccine in a mice model, as indicated by a reduced bacterial burden in the lungs. Multi-omics sequencing analysis revealed that E515 functions as an adjuvant by modulating critical pathways, including cytokine-cytokine receptor interaction, the IL-17 signaling pathway and the chemokine signaling pathway. This modulation also included interactions with beneficial species of bacteria including Alistipes, Odoribacter and Colidextribacter, as well as energy and lipid-related metabolites, thus highlighting its role as an immunomodulatory agent.

CONCLUSION

Collectively, our results demonstrate the huge potential of E515-Bb vaccine candidates, thus highlighting the vegetable oil original adjuvant E515 as a promising agent for the development of new veterinary vaccines.

Spectroscopic Studies of Lanthanide(III) Complexes with L-Malic Acid in Binary Systems

Binary systems of lanthanide ions (La, Nd, Gd, Ho, Tb, and Lu) with L-malic acid in molar ratios of 1:1 and 1:2 were studied. This study was carried out in aqueous solutions, and the composition of the formed complexes was confirmed using computer data analysis. The overall stability constants of the complexes and the equilibrium constants of the reaction were determined. The effect of ligand concentration on the composition of the internal coordination sphere of the central atom was observed. Changes in the coordination sphere of lanthanide ions were confirmed by spectroscopic measurements.

Research Progress on the Regulating Factors of Muscle Fiber Heterogeneity in Livestock: A Review

The type of muscle fiber plays a crucial role in the growth, development, and dynamic plasticity of animals' skeletal muscle. Additionally, it is a primary determinant of the quality of both fresh and processed meat. Therefore, understanding the regulatory factors that contribute to muscle fibers' heterogeneity is of paramount importance. Recent advances in sequencing and omics technologies have enabled comprehensive cross-verification of research on the factors affecting the types of muscle fiber across multiple levels, including the genome, transcriptome, proteome, and metabolome. These advancements have facilitated deeper exploration into the related biological questions. This review focused on the impact of individual characteristics, feeding patterns, and genetic regulation on the proportion and interconversion of different muscle fibers. The findings indicated that individual characteristics and feeding patterns significantly influence the type of muscle fiber, which can effectively enhance the type and distribution of muscle fibers in livestock. Furthermore, non-coding RNA, genes and signaling pathways between complicated regulatory mechanisms and interactions have a certain degree of impact on muscle fibers' heterogeneity. This, in turn, changes muscle fiber profile in living animals through genetic selection or environmental factors, and has the potential to modulate the quality of fresh meat. Collectively, we briefly reviewed the structure of skeletal muscle tissue and then attempted to review the inevitable connection between the quality of fresh meat and the type of muscle fiber, with particular attention to potential events involved in regulating muscle fibers' heterogeneity.

Integrated analysis of gut microbiome and its metabolites in ACE2-knockout and ACE2-overexpressed mice

Background

Aberrant activation of the classic renin-angiotensin system (RAS) and intestinal micro dysbiosis adversely affect insulin resistance (IR), dyslipidemia, and other metabolic syndrome markers. However, the action of angiotensin-converting enzyme 2 (ACE2) and gut health in systemic homeostasis vary, and their interaction is not completely understood.

Methods

We adopted a combinatory approach of metabolomics and fecal 16S rRNA analysis to investigate gut microbiota and metabolite in two different mouse models, ACE2 knockout (ACE2 KO) mice and the ACE2-overexpressing obese mice.

Results

16S rRNA gene sequencing revealed that ACE2 influences microbial community composition and function, and ACE2 KO mice had increased Deferribacteres, Alcaligenaceae, Parasutterella, Catenibacterium, and Anaerotruncus, with decreased short-chain fatty acid (SCFA)-producing bacteria (Marvinbryantia and Alistipes). In contrast, ACE2-overexpressed mice exhibited increased anti-inflammatory probiotic (Oscillospiraceae, Marinifilaceae, and Bifidobacteriaceae) and SCFA-producing microbes (Rikenellaceae, Muribaculaceae, Ruminococcaceae, Odoribacter, and Alistipes) and decreased Firmicutes/Bacteroidetes, Lactobacillaceae, Erysipelotrichaceae, and Lachnospiraceae. Metabolome analysis indicated differential metabolites in ACE2 KO and ACE2-overexpression mice, especially the glucolipid metabolism-related compounds. Furthermore, correlation analysis between gut microbiota and metabolites showed a dynamic mutual influence affecting host health.

Conclusion

Our study confirms for the first time a significant association between ACE2 status and gut microbiome and metabolome profiles, providing a novel mechanism for the positive effect of ACE2 on energy homeostasis.

Bound Polyphenols of Oat Bran Released by Gut Microbiota Mitigate High Fat Diet-Induced Oxidative Stress and Strengthen the Gut Barrier via the Colonic ROS/Akt/Nrf2 Pathway

Whole-grain foods are rich in bound polyphenols (BPs) whose health benefits were largely underestimated compared with free polyphenols. We first found that DFBP (dietary fiber with BPs from oat bran) exhibited stronger colonic antioxidant activities than DF. 16S rRNA sequencing showed that DFBP selectively changed gut microbial composition, which reciprocally released BPs from DFBP. Released polyphenols from DFBP reduced excessive colonic ROS and exhibited colonic antioxidant activities via the ROS/Akt/Nrf2 pathway revealed by transcriptome and western blot analysis. Colonic antioxidant activities of DFBP mediated by gut microbiota were next proven by treating mice with broad-spectrum antibiotics. Next, Clostridium butyricum, as a distinguished bacterium after DFBP intervention, improved colonic antioxidant capacities synergistically with DFBP in HFD-fed mice. This was explained by the upregulated mRNA expression of esterase, and cellulase of Clostridium butyricum participated in releasing BPs. Our results would provide a solid basis for explaining the health benefits of whole grains.

Nutritional Approaches Targeting Gut Microbiota in Oxidative-Stress-Associated Metabolic Syndrome: Focus on Early Life Programming

Metabolic syndrome (MetS) denotes a constellation of risk factors associated with the development of cardiovascular disease, with its roots potentially traced back to early life. Given the pivotal role of oxidative stress and dysbiotic gut microbiota in MetS pathogenesis, comprehending their influence on MetS programming is crucial. Targeting these mechanisms during the early stages of life presents a promising avenue for preventing MetS later in life. This article begins by examining detrimental insults during early life that impact fetal programming, ultimately contributing to MetS in adulthood. Following that, we explore the role of oxidative stress and the dysregulation of gut microbiota in the initiation of MetS programming. The review also consolidates existing evidence on how gut-microbiota-targeted interventions can thwart oxidative-stress-associated MetS programming, encompassing approaches such as probiotics, prebiotics, postbiotics, and the modulation of bacterial metabolites. While animal studies demonstrate the favorable effects of gut-microbiota-targeted therapy in mitigating MetS programming, further clinical investigations are imperative to enhance our understanding of manipulating gut microbiota and oxidative stress for the prevention of MetS.

Maternal Malic Acid May Ameliorate Oxidative Stress and Inflammation in Sows through Modulating Gut Microbiota and Host Metabolic Profiles during Late Pregnancy

Sows suffer oxidative stress and inflammation induced by metabolic burden during late pregnancy, which negatively regulates reproductive and lactating performances. We previously found that L-malic acid (MA) alleviated oxidative stress and inflammation and improved reproductive performances in sows. However, the mechanism underlying the MA's positive effects remains unexplored. Here, twenty Large White × Landrace sows with similar parity were randomly divided into two groups and fed with a basal diet or a diet supplemented with 2% L-malic acid complex from day 85 of gestation to delivery. The gut microbiome, fecal short-chain fatty acids, and untargeted serum metabolome were determined. Results showed that Firmicutes, Bacteroidota, and Spirochaetota were the top abundant phyla identified in late pregnancy for sows. Maternal MA supplementation modulated the composition but not the richness and diversity of gut microbiota during late pregnancy. Correlation analysis between gut microbiota and antioxidant capacity (or inflammation indicators) revealed that unclassified_f_Ruminococcaceae, unclassified_f_Lachnospiraceae, UCG-002, norank_f_norank_o_RF3, and Lactobacillus might play a role in anti-oxidation, and Lachnospiraceae_XPB1014_group, Lachnospiraceae_NK4A136_group, UCG-002, unclassified_f_Ruminococcaceae, Candidatus_Soleaferrea, norank_f_UCG-010, norank_f_norank_o_RF39, and unclassified_f_Lachnospiraceae might be involved in the anti-inflammatory effect. The improved antioxidant and inflammation status induced by MA might be independent of short chain fatty acid changes. In addition, untargeted metabolomics analysis exhibited different metabolic landscapes of sows in the MA group from in the control group and revealed the contribution of modified amino acid and lipid metabolism to the improved antioxidant capacity and inflammation status. Notably, correlation results of gut microbiota and serum metabolites, as well as serum metabolites and antioxidant capacity (or inflammation indicators), demonstrated that differential metabolism was highly related to the fecal microorganisms and antioxidant or inflammation indicators. Collectively, these data demonstrated that a maternal dietary supply of MA can ameliorate oxidative stress and inflammation in sows through modulating gut microbiota and host metabolic profiles during late pregnancy.

Application of Mendelian randomization to assess host gene-gut microbiota correlations in patients with esophageal cancer

Background

Increasing evidence suggests that esophageal cancer (ESCA) may be correlated with gut flora. However, their causal connection remains unclear. This study aimed to evaluate potential causal linkages and gene-gut microbiome associations between the gut microbiota and ESCA using Mendelian randomization (MR).

Methods

We analyzed the data using genome-wide association studies. The exposure factor and outcome variable were the gut microbiota and ESCA, respectively. The MR-Egger method, weighted median, inverse-variance weighted method, heterogeneity test, sensitivity analysis, and multiplicity analysis were used for the MR analysis. And it was validated using an external dataset. Further meta-analysis was performed to validate the robustness of this relationship. Finally, we annotated single nucleotide polymorphisms in the gut microbiota that were causally associated with ESCA to explore possible host gene-gut microbiota correlations in patients with ESCA.

Results

We identified four species with potential associations with ESCA. Three of these species had a negative causal relationship with ESCA (odds ratio (OR): 0.961; 95% confidence interval (CI): 0.923-0.971; p = 0.047 for Romboutsia; OR: 0.972; 95% CI: 0.921-0.961; p = 0.018 for Lachnospira; OR: 0.948; 95% CI: 0.912-0.970; p = 0.032 for Eubacterium). A positive causal relationship was observed between one bacterial group and ESCA (OR: 1.105; 95% CI: 1.010-1.072; p = 0.018 for Veillonella). External datasets show the same trend. This is further supported by meta-analysis. None of the data showed pleiotropy, and leave-one-out analysis indicated the reliability of these findings. The gut microbiomes of patients with ESCA may correlate with the 19 identified genes.

Conclusion

Our data indicate a potential causal link between these four gut bacteria and ESCA and identify a correlation between host genes and gut microbiota in ESCA, offering novel therapeutic options.