Predominant gut Lactobacillus murinus strain mediates anti-inflammaging effects in calorie-restricted mice

Microbial-derived Urolithin A Targets GLS1 to Inhibit Glutaminolysis and Attenuate Cirrhotic Portal Hypertension

BACKGROUND & AIMS

Cirrhotic portal hypertension (CPH) is the leading cause of mortality in patients with cirrhosis. Over 50% of patients with CPH treated with current clinical pharmacotherapy still present variceal bleeding or sometimes death owing to insufficient reduction in portal pressure. Elevated intrahepatic vascular resistance (IHVR) plays a fundamental role in increasing portal pressure. Because of its potent effect in reducing portal pressure and maintaining normal portal inflow to preserve liver function, lowering the IHVR is acknowledged as an optimal anti-CPH strategy but without clinical drugs. We aimed to investigate the protective effect of microbial-derived Urolithin A (UroA) in IHVR and CPH.

METHODS

Carbon tetrachloride or bile duct ligation surgery was administered to mice to induce liver fibrosis and CPH. 16S rRNA gene sequencing was used for microbial analysis. Transcriptomics and metabolomics analyses were employed to study the host and cell responses.

RESULTS

UroA was remarkably deficient in patients with CPH and was negatively correlated with disease severity. UroA deficiency was also confirmed in CPH mice and was associated with a reduced abundance of UroA-producing bacterial strain (Lactobacillus murinus, L. murinus). Glutaminolysis of hepatic stellate cells (HSCs) was identified as a previously unrecognized target of UroA. UroA inhibited the activity of glutaminase1 to suppress glutaminolysis, which counteracted fibrogenesis and contraction of HSCs and ameliorated CPH by relieving IHVR. Supplementation with UroA or L. murinus effectively ameliorated CPH in mice.

CONCLUSIONS

We for the first time identify the deficiency of gut microbial metabolite UroA as an important cause of CPH. We demonstrate that UroA exerts an excellent anti-CPH effect by suppressing HSC glutaminolysis to lower the IHVR, which highlighted its great potential as a novel therapeutic agent for CPH.

Guild-level signature of gut microbiome for diabetic kidney disease

Current microbiome signatures for chronic diseases such as diabetic kidney disease (DKD) are mainly based on low-resolution taxa such as genus or phyla and are often inconsistent among studies. In microbial ecosystems, bacterial functions are strain specific, and taxonomically different bacteria tend to form co-abundance functional groups called guilds. Here, we identified guild-level signatures for DKD by performing in-depth metagenomic sequencing and conducting genome-centric and guild-based analysis on fecal samples from 116 DKD patients and 91 healthy subjects. Redundancy analysis on 1,543 high-quality metagenome-assembled genomes (HQMAGs) identified 54 HQMAGs that were differentially distributed among the young healthy control group, elderly healthy control group, early-stage DKD patients (EDG), and late-stage DKD patients (LDG). Co-abundance network analysis classified the 54 HQMAGs into two guilds. Compared to guild 2, guild 1 contained more short-chain fatty acid biosynthesis genes and fewer genes encoding uremic toxin indole biosynthesis, antibiotic resistance, and virulence factors. Guild indices, derived from the total abundance of guild members and their diversity, delineated DKD patients from healthy subjects and between different severities of DKD. Age-adjusted partial Spearman correlation analysis showed that the guild indices were correlated with DKD disease progression and with risk indicators of poor prognosis. We further validated that the random forest classification model established with the 54 HQMAGs was also applicable for classifying patients with end-stage renal disease and healthy subjects in an independent data set. Therefore, this genome-level, guild-based microbial analysis strategy may identify DKD patients with different severity at an earlier stage to guide clinical interventions.

IMPORTANCE

Traditionally, microbiome research has been constrained by the reliance on taxonomic classifications that may not reflect the functional dynamics or the ecological interactions within microbial communities. By transcending these limitations with a genome-centric and guild-based analysis, our study sheds light on the intricate and specific interactions between microbial strains and diabetic kidney disease (DKD). We have unveiled two distinct microbial guilds with opposite influences on host health, which may redefine our understanding of microbial contributions to disease progression. The implications of our findings extend beyond mere association, providing potential pathways for intervention and opening new avenues for patient stratification in clinical settings. This work paves the way for a paradigm shift in microbiome research in DKD and potentially other chronic kidney diseases, from a focus on taxonomy to a more nuanced view of microbial ecology and function that is more closely aligned with clinical outcomes.

Kai-xin-san improves cognitive impairment in D-gal and Aβ25-35 induced ad rats by regulating gut microbiota and reducing neuronal damage

ETHNOPHARMACOLOGICAL RELEVANCE

Kai-Xin-San (KXS) is a classic herbal formula for the treatment and prevention of AD (Alzheimer's disease) with definite curative effect, but its mechanism, which involves multiple components, pathways, and targets, is not yet fully understood.

AIM OF THE STUDY

To verify the effect of KXS on gut microbiota and explore its anti-AD mechanism related with gut microbiota.

MATERIALS AND METHODS

AD rat model was established and evaluated by intraperitoneal injection of D-gal and bilateral hippocampal CA1 injections of Aβ25-35. The pharmacodynamics of KXS in vivo includes general behavior, Morris water maze test, ELISA, Nissl & HE staining and immunofluorescence. Systematic analysis of gut microbiota was conducted using 16S rRNA gene sequencing technology. The potential role of gut microbiota in the anti-AD effect of KXS was validated with fecal microbiota transplantation (FMT) experiments.

RESULTS

KXS could significantly improve cognitive impairment, reduce neuronal damage and attenuate neuroinflammation and colonic inflammation in vivo in AD model rats. Nine differential intestinal bacteria associated with AD were screened, in which four bacteria (Lactobacillus murinus, Ligilactobacillus, Alloprevotella, Prevotellaceae_NK3B31_group) were very significant.

CONCLUSION

KXS can maintain the ecological balance of intestinal microbiota and exert its anti-AD effect by regulating the composition and proportion of gut microbiota in AD rats through the microbiota-gut-brain axis.

Humid heat environment causes anxiety-like disorder via impairing gut microbiota and bile acid metabolism in mice

Climate and environmental changes threaten human mental health, but the impacts of specific environmental conditions on neuropsychiatric disorders remain largely unclear. Here, we show the impact of a humid heat environment on the brain and the gut microbiota using a conditioned housing male mouse model. We demonstrate that a humid heat environment can cause anxiety-like behaviour in male mice. Microbial 16 S rRNA sequencing analysis reveals that a humid heat environment caused gut microbiota dysbiosis (e.g., decreased abundance of Lactobacillus murinus), and metabolomics reveals an increase in serum levels of secondary bile acids (e.g., lithocholic acid). Moreover, increased neuroinflammation is indicated by the elevated expression of proinflammatory cytokines in the serum and cortex, activated PI3K/AKT/NF-κB signalling and a microglial response in the cortex. Strikingly, transplantation of the microbiota from mice reared in a humid heat environment readily recapitulates these abnormalities in germ-free mice, and these abnormalities are markedly reversed by Lactobacillus murinus administration. Human samples collected during the humid heat season also show a decrease in Lactobacillus murinus abundance and an increase in the serum lithocholic acid concentration. In conclusion, gut microbiota dysbiosis induced by a humid heat environment drives the progression of anxiety disorders by impairing bile acid metabolism and enhancing neuroinflammation, and probiotic administration is a potential therapeutic strategy for these disorders.

Unlocking the therapeutic potential of Huoxiang Zhengqi San in cold and high humidity-induced diarrhea: Insights into intestinal microbiota modulation and digestive enzyme activity

Huoxiang Zhengqi San (HXZQS), a traditional Chinese herbal formula, enjoys widespread use in Chinese medicine to treat diarrhea with cold-dampness trapped spleen syndrome (CDSS), which is induced by exposure to cold and high humidity stress. This study aimed to explore its therapeutic mechanisms in mice, particularly focusing on the intestinal microbiota. Forty male SPF-grade KM mice were allocated into two groups: the normal control group (H-Cc, n = 10) and the CDSS group (H-Mc, n = 30). After modeling, H-Mc was subdivided into H-Mc (n = 15) and HXZQS treatment (H-Tc, n = 15) groups. Intestinal samples were analyzed for enzyme activity and microbiota composition. Our findings demonstrated a notable reduction in intestinal lactase activity post-HXZQS treatment (P < 0.05). Lactobacillus johnsonii, Lactobacillus reuteri, and Lactobacillus murinus emerged as the main dominant species across most groups. However, in the H-Mc group, Clostridium sensu stricto 1 was identified as the exclusive dominant bacteria. LEfSe analysis highlighted Clostridiales vadinBB60 group and Corynebacterium as differential bacteria in the H-Tc group, and Cyanobacteria unidentified specie in the H-Mc group. Predicted microbiota functions aligned with changes in abundance, notably in cofactors and vitamins metabolism. The collinear results of the intestinal microbiota interaction network showed that HXZQS restored cooperative interactions among rare bacteria by mitigating their mutual promotion. The HXZQS decoction effectively alleviates diarrhea with CDSS by regulating intestinal microbiota, digestive enzyme activity, and microbiota interaction. Notably, it enhances Clostridium vadinBB60 and suppresses Cyanobacteria unidentified specie, warranting further study.

The Whole-Genome Sequencing and Probiotic Profiling of Lactobacillus reuteri Strain TPC32 Isolated from Tibetan Pig

Gut microbiota are the microbial organisms that play a pivotal role in intestinal health and during disease conditions. Keeping in view the characteristic functions of gut microbiota, in this study, Lactobacillus reuteri TPC32 (L. reuteri TPC32) was isolated and identified, and its whole genome was analyzed by the Illumina MiSeq sequencing platform. The results revealed that L. reuteri TPC32 had high resistance against acid and bile salts with fine in vitro antibacterial ability. Accordingly, a genome sequence of L. reuteri TPC32 has a total length of 2,214,495 base pairs with a guanine-cytosine content of 38.81%. Based on metabolic annotation, out of 2,212 protein-encoding genes, 118 and 101 were annotated to carbohydrate metabolism and metabolism of cofactors and vitamins, respectively. Similarly, drug-resistance and virulence genes were annotated using the comprehensive antibiotic research database (CARD) and the virulence factor database (VFDB), in which vatE and tetW drug-resistance genes were annotated in L. reuteri TPC32, while virulence genes are not annotated. The early prevention of L. reuteri TPC32 reduced the Salmonella typhimurium (S. Typhimurium) infection in mice. The results show that L. reuteri TPC32 could improve the serum IgM, decrease the intestinal cytokine secretion to relieve intestinal cytokine storm, reinforce the intestinal biochemical barrier function by elevating the sIgA expression, and strengthen the intestinal physical barrier function. Simultaneously, based on the 16S rRNA analysis, the L. reuteri TPC32 results affect the recovery of intestinal microbiota from disease conditions and promote the multiplication of beneficial bacteria. These results provide new insights into the biological functions and therapeutic potential of L. reuteri TPC32 for treating intestinal inflammation.

Pseudostellaria heterophylla polysaccharide mitigates Alzheimer's-like pathology via regulating the microbiota-gut-brain axis in 5 × FAD mice

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterised by neuroinflammation, for which gut dysbiosis may be implicated. Our previous study showed that treatment with Pseudostellaria heterophylla aqueous extract and one of its cyclopeptides, heterophyllin B, attenuate memory deficits via immunomodulation and neurite regeneration. However, whether Pseudostellaria heterophylla polysaccharide (PH-PS) exerts neuroprotective effects against AD and its underlying mechanisms remain unclear. The infrared spectrum, molecular weight, and carbohydrate composition of the PH-PS were determined. The results showed that PH-PS (Mw 8.771 kDa) was composed of glucose (57.78 %), galactose (41.52 %), and arabinose (0.70 %). PH-PS treatment ameliorated learning and spatial memory deficits, reduced amyloid β build-up, and suppressed reactive glia and astrocytes in 5 × FAD mice. 16S rRNA sequencing further showed that PH-PS remodelled the intestinal flora composition by promoting probiotic microbiota, such as Lactobacillus, Muribaculum, Monoglobus, and [Eubacterium]_siraeum_group, and suppressing inflammation-related UCG-009 and Blautia. Additionally, PH-PS restored intestinal barrier function; ameliorated peripheral inflammation by reducing the secretion of inflammatory cytokines, thereby converting M1 microglia and A1 astrocyte toward beneficial M2 and A2 phenotypes; and contributed to Aβ plaques clearance by upregulation of insulin degradation enzyme and neprilysin. Collectively, our findings demonstrate that PH-PS may prevent the progression of AD via modulation of the gut microbiota and regulation of glial polarisation, which could provide evidence to design a potential diet therapy for preventing or curing AD.

Decoction derived from Allium ascalonicum L. bulbs and Sojae Semen Praeparatum alleviates wind-cold-type common cold via Nrf2/HO-1 pathway and modulation of Lactobacillus murinus level

Background

Cong-Chi decoction (CCD) is made using Allium ascalonicum L. (shallot) bulbs and Sojae Semen Praeparatum (SSP). Shallot bulbs and SSP are both used regularly in traditional Chinese medicine; however, there are no recent pharmacological studies on their synergistic effects. Despite their roles in the treatment of the common cold for thousands of years, their pharmacological mechanisms of action against wind-cold-type common cold are yet to be explored comprehensively.

Methods

A mouse model was standardized using wind-cold modeling equipment to study the anti-inflammatory, antioxidant, and antiapoptotic effects of CCD. Then, 16S rRNA sequencing was employed to analyze the association between Lactobacillus murinus and changes in body temperature. Additionally, the antipyretic effects of L. murinus were validated via animal experiments.

Results

The results indicate that CCD improves the symptoms of wind-cold by reducing fever, levels of pro-inflammatory factors, and cellular apoptosis, as well as increasing the blood leukocyte and lymphocyte counts, thereby alleviating lung tissue damage. The effects of CCD are mediated by upregulation of pulmonary Nrf2 and HO-1 expressions, thereby reducing oxidative damage in the lungs, in addition to other anti-inflammatory mechanisms. Furthermore, CCD increases the abundance of L. murinus in the intestinal tract. The animal experiments confirm that L. murinus ameliorates fever in mice.

Conclusion

CCD exhibits remarkable antioxidant and anti-inflammatory properties for effectively treating wind-cold-type common cold. Furthermore, its regulatory effects on L. murinus represent a novel mechanism for product development.

Distribution and roles of Ligilactobacillus murinus in hosts

Ligilactobacillus murinus, a member of the Ligilactobacillus genus, holds significant potential as a probiotic. While research on Ligilactobacillus murinus has been relatively limited compared to well-studied probiotic lactic acid bacteria such as Limosilactobacillus reuteri and Lactobacillus gasseri, a mounting body of evidence highlights its extensive involvement in host intestinal metabolism and immune activities. Moreover, its abundance exhibits a close correlation with intestinal health. Notably, beyond the intestinal context, Ligilactobacillus murinus is gaining recognition for its contributions to metabolism and regulation in the oral cavity, lungs, and vagina. As such, Ligilactobacillus murinus emerges as a potential probiotic candidate with a pivotal role in supporting host well-being. This review delves into studies elucidating the multifaceted roles of Ligilactobacillus murinus. It also examines its medicinal potential and associated challenges, underscoring the imperative to delve deeper into unraveling the mechanisms of its actions and exploring its health applications.

A New Murine Undernutrition Model Based on Complementary Feeding of Undernourished Children Causes Damage to the Morphofunctional Intestinal Epithelium Barrier

BACKGROUND

Complementary feeding is critical in establishing undernutrition. However, experimental undernourished diets do not represent the amount of nutrients in the complementary diets of undernourished children.

OBJECTIVES

To develop, validate, and evaluate the impact of a new murine model of undernutrition on the intestinal epithelium, based on the complementary diet of undernourished children from 7 countries with low-socioeconomic power belonging to the Malnutrition-Enteric Diseases (MAL-ED) cohort study.

METHODS

We used the difference in the percentage of energy, macronutrients, fiber and zinc in the complementary diet of children without undernutrition compared with stunting (height-for-age Z-score < -2) for the MAL-ED diet formulation. Subsequently, C57BL/6 mice were fed a control diet (AIN-93M diet) or MAL-ED diet for 28 d. Weight was measured daily; body composition was measured every 7 d; lactulose:mannitol ratio (LM) and morphometry were evaluated on days 7 and 28; the cotransport test and analysis of intestinal transporters and tight junctions were performed on day 7.

RESULTS

The MAL-ED diet presented -8.03% energy, -37.46% protein, -24.20% lipid, -10.83% zinc, +5.93% carbohydrate, and +45.17% fiber compared with the control diet. This diet rapidly reduced weight gain and compromised body growth and energy reserves during the chronic period (P < 0.05). In the intestinal epithelial barrier, this diet caused an increase in the LM (P < 0.001) and reduced (P < 0.001) the villous area associated with an increase in FAT/CD36 in the acute period and increased (P < 0.001) mannitol excretion in the chronic period.

CONCLUSIONS

The MAL-ED diet induced undernutrition in mice, resulting in acute damage to the integrity of the intestinal epithelial barrier and a subsequent increase in the intestinal area during the chronic period. This study introduces the first murine model of undernutrition for the complementary feeding phase, based on data from undernourished children in 7 different countries.

Extraction, structure and bioactivities of polysaccharide from root of Arctium lappa L.: A review

Arctium lappa L. root is a well-known Chinese medicine with high medicinal and food values. Arctium lappa L. root polysaccharide (ALP), as the main component and bioactive substance, has a variety of biological activities, including anti-inflammatory, antioxidant, hypoglycemic, hypolipidemic, antithrombotic, immunomodulatory activity and improvement of intestinal flora. The biological activities of polysaccharides are closely related to their structures, and different extraction and purification methods will yield different polysaccharide structures. As a kind of natural polysaccharide, ALP has a broad application prospect in drug carrier. In this paper, we reviewed the research progress on the extraction, purification, structural characterization, biological activities, structure-activity relationship and drug carrier application of ALP, in order to provide basic reference for the development and application of medical and health care value. At the same time, the shortcomings of ALP research are discussed in depth, and the potential development prospect and future research direction are prospected.

Human-derived bacterial strains mitigate colitis via modulating gut microbiota and repairing intestinal barrier function in mice

BACKGROUND

Unbalanced gut microbiota is considered as a pivotal etiological factor in colitis. Nevertheless, the precise influence of the endogenous gut microbiota composition on the therapeutic efficacy of probiotics in colitis remains largely unexplored.

RESULTS

In this study, we isolated bacteria from fecal samples of a healthy donor and a patient with ulcerative colitis in remission. Subsequently, we identified three bacterial strains that exhibited a notable ability to ameliorate dextran sulfate sodium (DSS)-induced colitis, as evidenced by increased colon length, reduced disease activity index, and improved histological score. Further analysis revealed that each of Pediococcus acidilactici CGMCC NO.17,943, Enterococcus faecium CGMCC NO.17,944 and Escherichia coli CGMCC NO.17,945 significantly attenuated inflammatory responses and restored gut barrier dysfunction in mice. Mechanistically, bacterial 16S rRNA gene sequencing indicated that these three strains partially restored the overall structure of the gut microbiota disrupted by DSS. Specially, they promoted the growth of Faecalibaculum and Lactobacillus murinus, which were positively correlated with gut barrier function, while suppressing Odoribacter, Rikenella, Oscillibacter and Parasutterella, which were related to inflammation. Additionally, these strains modulated the composition of short chain fatty acids (SCFAs) in the cecal content, leading to an increase in acetate and a decrease in butyrate. Furthermore, the expression of metabolites related receptors, such as receptor G Protein-coupled receptor (GPR) 43, were also affected. Notably, the depletion of endogenous gut microbiota using broad-spectrum antibiotics completely abrogated these protective effects.

CONCLUSIONS

Our findings suggest that selected human-derived bacterial strains alleviate experimental colitis and intestinal barrier dysfunction through mediating resident gut microbiota and their metabolites in mice. This study provides valuable insights into the potential therapeutic application of probiotics in the treatment of colitis.

Communication mediated interaction between bacteria and microalgae advances photogranulation

Recently, photogranules composed of bacteria and microalgae for carbon-negative nitrogen removal receive extensive attention worldwide, yet which type of bacteria is helpful for rapid formation of photogranules and whether they depend on signaling communication remain elusive. Varied signaling communication was analyzed using metagenomic method among bacteria and microalgae in via of two types of experimentally verified signaling molecule from bacteria to microalgae, which include indole-3-acetic acid (IAA) and N-acyl homoserine lactones (AHLs) during the operation of photo-bioreactors. Signaling communication is helpful for the adaptability of bacteria to survive with algae. Compared with non-signaling bacteria, signaling bacteria more easily adapt to the varied conditions, evidenced by the increased abundance in the operated reactors. Signaling bacteria are easier to enter the phycosphere, and they dominate the interactions between bacteria and algae rather than non-signaling bacteria. The co-abundance groups (CAGs) with signaling bacteria possess higher abundance than that without signaling bacteria (22.27 % and 6.67 %). Importantly, signaling bacteria accessibly interact with microalgae, which possess higher degree centralities and 32.50 % of them are keystone nodes in the network, in contrast to only 18.66 % of non-signaling bacteria. Thauera carrying both IAA and AHLs synthase genes are highly enriched and positively correlated with nitrogen removal rate. Our work not only highlights the essential roles of signaling communication between microalgae and bacteria in the development of photogranules, but also enriches our understanding of microbial sociobiology.

Polyguluronate alleviates ulcerative colitis by targeting the gut commensal Lactobacillus murinus and its anti-inflammatory metabolites

Polyguluronate (PG) is a fermentable polysaccharide from edible algae. The present study was designed to investigate the therapeutic effect of PG on ulcerative colitis (UC) and its underlying mechanisms. Our results suggest that oral intake of PG attenuates UC and improves gut microbiota dysbiosis by promoting the growth of Lactobacillus spp. in dextran sulfate sodium-fed mice. Five different species of Lactobacillus were isolated from the feces of PG-treated mice and L. murinus was identified to have the best anti-colitis effect, suggesting a critical role for L. murinus in mediating the therapeutic effect of PG. Furthermore, PG was degraded potentially by the beta-glucuronidase from L. murinus and adding PG to the culture medium of L. murinus remarkably increased its production of anti-inflammatory metabolites, including itaconic acid, cis-11,14-eicosadienoic acid, and 3-amino-3-(2-chlorophenyl)-propionic acid. Additionally, L. salivarius, a human intestine-derived PG-utilizing species that is closely related to L. murinus, was also demonstrated to have potent anti-colitis effects, suggesting that it is a candidate target of PG in the human gut. Altogether, our study illustrates an unprecedented application of PG in the treatment of UC and establishes the basis for understanding its therapeutic effect from the perspective of L. murinus and its metabolites.

Endogenous Coriobacteriaceae enriched by a high-fat diet promotes colorectal tumorigenesis through the CPT1A-ERK axis

A high-fat diet (HFD) may be linked to an increased colorectal cancer (CRC) risk. Stem cell proliferation and adipokine release under inflammatory and obese conditions are the main factors regulating CRC progression. Furthermore, alterations in intestinal flora have been linked to tumorigenesis and tumour progression. However, whether a HFD can promote CRC occurrence by altering intestinal flora remains unclear. The objective of this study was to identify bacterial strains enriched by a HFD and investigate the association and mechanism by which a HFD and bacterial enrichment promote CRC occurrence and development. In this study, the intestinal microbiota of mice was assessed using 16S rRNA and metagenomic sequencing. Serum metabolites of HFD-fed mice were assessed using tandem liquid chromatography-mass spectrometry. CRC cell lines and organoids were co-cultured with Coriobacteriaceae to evaluate the effect of these bacteria on the CPT1A-ERK signalling pathway. We found that Coriobacteriaceae were enriched in the colons of HFD-fed mice. An endogenous Coriobacteriaceae strain, designated as Cori.ST1911, was successfully isolated and cultured from the stools of HFD-fed mice, and the tumorigenic potential of Cori.ST1911 in CRC was validated in several CRC mouse models. Furthermore, Cori.ST1911 increased acylcarnitine levels by activating CPT1A, demonstrating the involvement of the CPT1A-ERK axis. We also found that the endogenous Lactobacillus strain La.mu730 can interfere with Cori.ST1911 colonisation and restore gut barrier function. In conclusion, we identified a novel endogenous intestinal Coriobacteriaceae, Cori.ST1911, which might lead to a new gut microbiota intervention strategy for the prevention and treatment of CRC.

The influence of the gut microbiome on ovarian aging

Ovarian aging occurs prior to the aging of other organ systems and acts as the pacemaker of the aging process of multiple organs. As life expectancy has increased, preventing ovarian aging has become an essential goal for promoting extended reproductive function and improving bone and genitourinary conditions related to ovarian aging in women. An improved understanding of ovarian aging may ultimately provide tools for the prediction and mitigation of this process. Recent studies have suggested a connection between ovarian aging and the gut microbiota, and alterations in the composition and functional profile of the gut microbiota have profound consequences on ovarian function. The interaction between the gut microbiota and the ovaries is bidirectional. In this review, we examine current knowledge on ovary-gut microbiota crosstalk and further discuss the potential role of gut microbiota in anti-aging interventions. Microbiota-based manipulation is an appealing approach that may offer new therapeutic strategies to delay or reverse ovarian aging.

Mechanisms for the biological activity of Gastrodia elata Blume and its constituents: A comprehensive review on sedative-hypnotic, and antidepressant properties

BACKGROUND

Insomnia and depressive disorder are two common symptoms with a reciprocal causal relationship in clinical practice, which are usually manifested in comorbid form. Several medications have been widely used in the treatment of insomnia and depression, but most of these drugs show non-negligible side effects. Currently, many treatments are indicated for insomnia and depressive symptom, including Chinese herbal medicine such as Gastrodia elata Blume (G. elata), which has excellent sedative-hypnotic and antidepressant effects in clinical and animal studies.

PURPOSE

To summarize the mechanisms of insomnia and depression and the structure-activity mechanism for G. elata to alleviate these symptoms, particularly by hypothalamic-pituitary-adrenal (HPA) axis and intestinal flora, aiming to discover new approaches for the treatment of insomnia and depression.

METHODS

The following electronic databases were searched from the beginning to November 2023: PubMed, Web of Science, Google Scholar, Wanfang Database, and CNKI. The following keywords of G. elata were used truncated with other relevant topic terms, such as depression, insomnia, antidepressant, sedative-hypnotic, neuroprotection, application, safety, and toxicity.

RESULTS

Natural compounds derived from G. elata could alleviate insomnia and depressive disorder, which is involved in monoamine neurotransmitters, inflammatory response, oxidative stress, and gut microbes, etc. Several clinical trials showed that G. elata-derived natural compounds that treat depression and insomnia have significant and safe therapeutic effects, but further well-designed clinical and toxicological studies are needed.

CONCLUSION

G. elata exerts a critical role in treating depression and insomnia due to its multi-targeting properties and fewer side effects. However, more clinical and toxicological studies should be performed to further explore the sedative-hypnotic and antidepressant mechanisms of G. elata and provide more evidence and recommendations for its clinical application. Our review provides an overview of G. elata treating insomnia with depression for future research direction.

Ligilactobacillus Salivarius improve body growth and anti-oxidation capacity of broiler chickens via regulation of the microbiota-gut-brain axis

Certain strains of probiotic bacteria can secret functional substances namely digestive enzymes and functional peptides to regulate physiological conditions such as digestion and anti-oxidation, which are often incorporated in industrial broiler chick production. However, few studies have detailed the action mechanisms and effects of these bacteria on regulating growth and anti-oxidation levels in broiler chickens. Ligilactobacillus salivarius is a strain of probiotic bacteria used as dietary supplement. In the present study, Ligilactobacillus salivarius was evaluated for its secreted digestive enzymes in vitro. To detailed evaluate the action mechanisms and effects of gastrointestinal tract (GIT) microbiota on alleviating anti-oxidation levels of broiler chickens through the gut-brain axis. Ligilactobacillus salivarius was cultured and supplemented in the food of broilers to evaluate the probiotic effect on growth and anti-oxidation by modulation of gut microbial composition and its functional metabolites using metagenomic and metabolomic assays. Biochemical results showed that Ligilactobacillus salivarius secreted digestive enzymes: protease, lipase, and amylase. Broiler chickens with Ligilactobacillus salivarius supplemented for 42 days, showed increased body weights, a reduced oxidative status, decreased malondialdehyde levels, and improved activities rates of total superoxide dismutase, glutathione peroxidase IIand IV improved. The microbial composition of caecum was more abundant than those broiler without probiotics supplementation, owing 400 of total number (489) of bacterial operational taxonomic units (OTU). The genera of Lactobacillus, Megamonas, Ruminoccoccaceae, Ruminococcus, Alistipes and Helicobacter shared the dominant proportion of Candidatus _Arthromitus compared with the control chickens. These functional bacteria genera assisted in the transportation and digestion of amino acids, carbohydrates, and ions, synthesis of cellular membranes, and anti-oxidation. Uncultured_organism_g_ Anaerosporobacter, Lactobacillus salivarius, uncultured_bacterium_g_ Ruminococcaceae_UCG-014, uncultured_bacterium_g_ Peptococcus were strongly and positively correlated with body growth performance and anti-oxidation. A metabonomic assay suggested that the secreted of gamma-aminobutyric acid and monobactam was metabolized according to the Kyoto Encyclopedia of Genes and Genomes analysis. In conclusion, Ligilactobacillus salivarius optimized microbial composition of the caecum and secreted functional peptides through gut-brain axis to improve the body growth and antioxidation of broiler chicken.

The Beneficial Effects of Dietary Interventions on Gut Microbiota-An Up-to-Date Critical Review and Future Perspectives

Different dietary interventions, especially intermittent fasting, are widely used and promoted by physicians; these regimens have been studied lately for their impact on the gut microbiota composition/function and, consequently, on the general physiopathological processes of the host. Studies are showing that dietary components modulate the microbiota, and, at the same time, the host metabolism is deeply influenced by the different products resulting from nutrient transformation in the microbiota compartment. This reciprocal relationship can potentially influence even drug metabolism for chronic drug regimens, significantly impacting human health/disease. Recently, the influence of various dietary restrictions on the gut microbiota and the differences between the effects were investigated. In this review, we explored the current knowledge of different dietary restrictions on animal and human gut microbiota and the impact of these changes on human health.

Astragalus membranaceus and Salvia miltiorrhiza ameliorate diabetic kidney disease via the "gut-kidney axis"

BACKGROUND

The combination of Astragalus membranaceus and Salvia miltiorrhiza (AS) is an effective prescription for treating diabetic kidney disease (DKD) in traditional Chinese medicine. Its efficacy in treating DKD has been confirmed, but the potential regulatory mechanism has not yet been fully clarified.

PURPOSE

To explore the mechanism by which AS regulates the "gut-metabolism-transcription" coexpression network under the action of the "gut-kidney axis" to ameliorate DKD.

METHODS

SD rats were used to establish the DKD model by injecting STZ. After AS intervention, the structure and function of the kidney and colon were observed. We sequenced the gut microbiota utilizing 16S rDNA, identified serum differential metabolites using LC‒MS/MS, and observed renal mRNA expression by RNA seq. The "gut-metabolism-transcription" coexpression network was further constructed, and the target bacteria, target metabolites, and target genes of AS were ultimately screened and validated.

RESULTS

AS improved renal pathology and functional damage and increased the abundance of Akkermansia, Akkermansia_muciniphila, Lactobacillus and Lactobacillus_murinus. Fourteen target metabolites of AS were identified, which were mainly concentrated in 19 KEGG pathways, including sphingolipid metabolism and glycerophospholipid metabolism. Sixty-three target mRNAs of AS were identified. The top 20 pathways were closely related to glycolipid metabolism, and 14 differential mRNAs were expressed in these pathways. Correlation analysis showed that Akkermansia, Akkermansia muciniphila, Lactobacillus and Lactobacillus murinus were closely associated with sphingolipid metabolism, glycerophospholipid metabolism, arachidonic acid metabolism, ascorbate and aldarate metabolism and galactose metabolism. Moreover, the target metabolites and target mRNAs of AS were also enriched in five identical pathways of sphingolipid metabolism, glycerophospholipid metabolism, arachidonic acid metabolism, ascorbate and aldarate metabolism and galactose metabolism, including 8 different metabolites, such as sphingosine, and 5 different genes, such as Kng1. The 8 metabolites had high AUC prediction values, and the validation of the 5 genes was consistent with the sequencing results.

CONCLUSION

Our research showed that AS can improve DKD via the "gut-kidney axis". Akkermansia muciniphila and Lactobacillus murinus were the main driving bacteria, and five pathways related to glycolipid metabolism, especially sphingolipid metabolism and glycerophospholipid metabolism, may be important follow-up reactions and regulatory mechanisms.

Vaginal microbial dynamics and pathogen colonization in a humanized microbiota mouse model

Vaginal microbial composition is associated with differential risk of urogenital infection. Although Lactobacillus spp. are thought to confer protection against infection, the lack of in vivo models resembling the human vaginal microbiota remains a prominent barrier to mechanistic discovery. Using 16S rRNA amplicon sequencing of C57BL/6J female mice, we found that vaginal microbial composition varies within and between colonies across three vivaria. Noting vaginal microbial plasticity in conventional mice, we assessed the vaginal microbiome of humanized microbiota mice (HMbmice). Like the community structure in conventional mice, HMbmice vaginal microbiota clustered into community state types but, uniquely, HMbmice communities were frequently dominated by Lactobacillus or Enterobacteriaceae. Compared to conventional mice, HMbmice were less susceptible to uterine ascension by urogenital pathobionts group B Streptococcus (GBS) and Prevotella bivia. Although Escherichia and Lactobacillus both correlated with the absence of uterine GBS, vaginal pre-inoculation with exogenous HMbmouse-derived E. coli, but not Ligilactobacillus murinus, reduced vaginal GBS burden. Overall, HMbmice serve as a useful model to elucidate the role of endogenous microbes in conferring protection against urogenital pathogens.

Targeting IL-23 for the interception of obesity-associated colorectal cancer

Inflammation and obesity are two major factors that promote Colorectal cancer (CRC). Our recent data suggests that interleukin (IL)-23, is significantly elevated in CRC tumors and correlates with patient obesity, tumor grade and survival. Thus, we hypothesize that obesity and CRC may be linked via inflammation and IL-23 may be a potential target for intervention in high-risk patients. TCGA dataset and patient sera were evaluated for IL-23A levels. IL-23A [IL-23 p19-/-] knockout (KO) mice were crossed to Apcmin/+ mice and progeny were fed low-fat or high-fat diets. At termination intestines were evaluated for tumorigenesis. Tumors, serum, and fecal contents were analyzed for protein biomarkers, cytokines, and microbiome profile respectively. IL-23A levels are elevated in the sera of patients with obesity and colon tumors. Genetic ablation of IL-23A significantly suppressed colonic tumor multiplicity (76-96 %) and incidence (72-95 %) in male and female mice. Similarly, small-intestinal tumor multiplicity and size were also significantly reduced in IL-23A KO mice. IL-23A knockdown in Apcmin/+ mice fed high-fat diet, also resulted in significant suppression of colonic (50-58 %) and SI (41-48 %) tumor multiplicity. Cytokine profiling showed reduction in several circulating pro-inflammatory cytokines including loss of IL-23A. Biomarker analysis suggested reduced tumor cell proliferation and immune modulation with an increase in tumor-infiltrating CD4+ and CD8+ T-lymphocytes in the IL-23A KO mice compared to controls. Fecal microbiome analysis revealed potentially beneficial changes in the bacterial population profile. In summary, our data indicates a tumor promoting role for IL-23 in CRC including diet-induced obesity. With several IL-23 targeted therapies in clinical trials, there is a great potential for targeting this cytokine for CRC prevention and therapy.

Propionic Acid Driven by the Lactobacillus johnsonii Culture Supernatant Alleviates Colitis by Inhibiting M1 Macrophage Polarization by Modulating the MAPK Pathway in Mice

In this study, we investigated the effects of Lactobacillus johnsonii on the mouse colitis model. The results showed that the supernatant of the L. johnsonii culture alleviated colitis and remodeled gut microbiota, represented by an increased abundance of bacteria producing short-chain fatty acids, leading to an increased concentration of propionic acid in the intestine. Further studies revealed that propionic acid inhibited activation of the MAPK signaling pathway and polarization of M1 macrophages. Macrophage clearance assays confirmed that macrophages are indispensable for alleviating colitis through propionic acid. In vitro experiments showed that propionic acid directly inhibited the MAPK signaling pathway in macrophages and reduced M1 macrophage polarization, thereby inhibiting the secretion of pro-inflammatory cytokines. These findings improve our understanding of how L. johnsonii attenuates inflammatory bowel disease (IBD) and provide valuable insights for identifying molecular targets for IBD treatment in the future.

Lactiplantibacillus plantarum Strain FLPL05 Promotes Longevity in Mice by Improving Intestinal Barrier

This study aimed to evaluate the effect of oral administration of probiotic Lactiplantibacillus plantarum FLPL05 on the lifespan and intestinal barrier of aged mice. L. plantarum FLPL05 significantly prolonged the lifespan of naturally aged mice, maintained the integrity of intestinal mucosal barrier, and reduced the inflammation level. The analysis of intestinal microbiota revealed that L. plantarum FLPL05 increased the relative abundance of Firmicutes and decreased the abundance of Bacteroides, accompanied by the increased proportions of Lactobacillus and Desulfovibrio in intestinal microbiota as well as the reduced proportions of Roseburia and Parabacteroides. The intestinal proteomics revealed that the oral administration of L. plantarum FLPL05 significantly upregulated the tight junction and simultaneously inhibited the expression of apoptotic-related proteins. The immunohistochemistry results also indicated that L. plantarum FLPL05 promoted the expression of tight junction proteins (ZO-1 and occludin) and reduced the apoptosis of intestinal cells. In addition, L. plantarum FLPL05 and the fermented supernatant increased the activity of HT-29. L. plantarum FLPL05 prolonged the lifespan by improving the health of the intestinal tract after aging and may be a potential probiotic and nutritional supplement for the elderly people.

Ootheca mantidis mitigates renal fibrosis in mice by the suppression of apoptosis via increasing the gut microbe Akkermansia muciniphila and modulating glutamine metabolism

Renal interstitial fibrosis (RIF), a progressive process affecting the kidneys in chronic kidney disease (CKD), currently lacks an effective therapeutic intervention. Traditional Chinese medicine (TCM) has shown promise in reducing RIF and slowing CKD progression. In this study, we demonstrated the dose-dependent attenuation of RIF by Ootheca mantidis (SPX), a commonly prescribed TCM for CKD, in a mouse model of unilateral ureteral obstruction (UUO). RNA-sequencing analysis suggested that SPX treatment prominently downregulated apoptosis and inflammation-associated pathways, thereby inhibiting the fibrogenic signaling in the kidney. We further found that transplantation of fecal microbiota from SPX-treated mice conferred protection against renal injury and fibrosis through suppressing apoptosis in UUO mice, indicating that SPX ameliorated RIF via remodeling the gut microbiota and reducing apoptosis in the kidneys. Further functional exploration of the gut microbiota combined with fecal metabolomics revealed increased levels of some probiotics, including Akkermansia muciniphila (A. muciniphila), and modulations in glutamine-related amino acid metabolism in UUO mice treated with SPX. Subsequent colonization of A. muciniphila and supplementation with glutamine effectively mitigated cell apoptosis and RIF in UUO mice. Collectively, these findings unveil a functionally A. muciniphila- and glutamine-involved gut-renal axis that contributes to the action of SPX, and provide important clue for the therapeutic potential of SPX, A. muciniphila, and glutamine in combatting RIF.

Blue Light-Emitting Diode Irradiation Without a Photosensitizer Alters Oral Microbiome Composition of Ligature-Induced Periodontitis in Mice

Objective: This study investigated the suppressive effects of blue light-emitting diode (LED) irradiation on bone resorption and changes in the oral microbiome of mice with ligature-induced periodontitis. Background: Wavelength of blue light has antimicrobial effects; however, whether blue LED irradiation alone inhibits the progression of periodontitis remains unclear. Methods: Nine-week-old male mice ligated ligature around the right maxillary second molar was divided into ligation alone (Li) and ligation with blue LED irradiation (LiBL) groups. The LiBL group underwent blue LED (wavelength, 455 nm) irradiation four times in a week at 150 mW/cm2 without a photosensitizer on the gingival tissue around the ligated tooth at a distance of 5 mm for 5 min. The total energy density per day was 45 J/cm2. Bone resorption was evaluated using micro-computed tomography at 8 days. Differences in the oral microbiome composition of the collected ligatures between the Li and LiBL groups were analyzed using next-generation sequencing based on the 16S rRNA gene from the ligatures. Results: Blue LED irradiation did not suppress bone resorption caused by ligature-induced periodontitis. However, in the LiBL group, the α-diversity, number of observed features, and Chao1 were significantly decreased. The relative abundances in phylum Myxococcota and Bacteroidota were underrepresented, and the genera Staphylococcus, Lactococcus, and Lactobacillus were significantly overrepresented by blue LED exposure. Metagenomic function prediction indicated an increase in the downregulated pathways related to microbial energy metabolism after irradiation. The co-occurrence network was altered to a simpler structure in the LiBL group, and the number of core genera decreased. Conclusions: Blue LED irradiation altered the composition and network of the oral microbiome of ligature-induced periodontitis in mice.

Gut microbiota modulate distal symmetric polyneuropathy in patients with diabetes

The pathogenic mechanisms underlying distal symmetric polyneuropathy (DSPN), a common neuropathy in patients with diabetes mellitus (DM), are not fully understood. Here, we discover that the gut microbiota from patients with DSPN can induce a phenotype exhibiting more severe peripheral neuropathy in db/db mice. In a randomized, double-blind, and placebo-controlled trial (ChiCTR1800017257), compared to 10 patients who received placebo, DSPN was significantly alleviated in the 22 patients who received fecal microbiota transplants from healthy donors, independent of glycemic control. The gut bacterial genomes that correlated with the Toronto Clinical Scoring System (TCSS) score were organized in two competing guilds. Increased guild 1, which had higher capacity in butyrate production, and decreased guild 2, which harbored more genes in synthetic pathway of endotoxin, were associated with improved gut barrier integrity and decreased proinflammatory cytokine levels. Moreover, matched enterotype between transplants and recipients showed better therapeutic efficacy with more enriched guild 1 and suppressed guild 2. Thus, changes in these two competing guilds may play a causative role in DSPN and have the potential for therapeutic targeting.

Metabolomics: A useful tool for ischemic stroke research

Ischemic stroke (IS) is a multifactorial and heterogeneous disease. Despite years of studies, effective strategies for the diagnosis, management and treatment of stroke are still lacking in clinical practice. Metabolomics is a growing field in systems biology. It is starting to show promise in the identification of biomarkers and in the use of pharmacometabolomics to help patients with certain disorders choose their course of treatment. The development of metabolomics has enabled further and more biological applications. Particularly, metabolomics is increasingly being used to diagnose diseases, discover new drug targets, elucidate mechanisms, and monitor therapeutic outcomes and its potential effect on precision medicine. In this review, we reviewed some recent advances in the study of metabolomics as well as how metabolomics might be used to identify novel biomarkers and understand the mechanisms of IS. Then, the use of metabolomics approaches to investigate the molecular processes and active ingredients of Chinese herbal formulations with anti-IS capabilities is summarized. We finally summarized recent developments in single cell metabolomics for exploring the metabolic profiles of single cells. Although the field is relatively young, the development of single cell metabolomics promises to provide a powerful tool for unraveling the pathogenesis of IS.

The Role of Diet and Gut Microbiota Interactions in Metabolic Homeostasis

Diet is a pivotal determinant in shaping the structure and function of resident microorganisms in the gut through different food components, nutritive proportion, and calories. The effects of diet on host metabolism and physiology can be mediated through the gut microbiota. Gut microbiota-derived metabolites have been shown to regulate glucose and lipid metabolism, energy consumption, and the immune system. On the other hand, emerging evidence indicates that baseline gut microbiota could predict the efficacy of diet intervention, highlighting gut microbiota can be harnessed as a biomarker in personalized nutrition. In this review, the alterations of gut microbiota in different dietary components and dietary patterns, and the potential mechanisms in the diet-microbiota crosstalk are summarized to understand the interactions of diet and gut microbiota on the impact of metabolic homeostasis.

Altered Respiratory Microbiomes, Plasma Metabolites, and Immune Responses in Influenza A Virus and Methicillin-Resistant Staphylococcus aureus Coinfection

Influenza A virus (IAV)-methicillin-resistant Staphylococcus aureus (MRSA) coinfection causes severe respiratory infections. The host microbiome plays an important role in respiratory tract infections. However, the relationships among the immune responses, metabolic characteristics, and respiratory microbial characteristics of IAV-MRSA coinfection have not been fully studied. We used specific-pathogen-free (SPF) C57BL/6N mice infected with IAV and MRSA to build a nonlethal model of IAV-MRSA coinfection and characterized the upper respiratory tract (URT) and lower respiratory tract (LRT) microbiomes at 4 and 13 days postinfection by full-length 16S rRNA gene sequencing. Immune response and plasma metabolism profile analyses were performed at 4 days postinfection by flow cytometry and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The relationships among the LRT microbiota, the immune response, and the plasma metabolism profile were analyzed by Spearman's correlation analysis. IAV-MRSA coinfection showed significant weight loss and lung injury and significantly increased loads of IAV and MRSA in bronchoalveolar lavage fluid (BALF). Microbiome data showed that coinfection significantly increased the relative abundances of Enterococcus faecalis, Enterobacter hormaechei, Citrobacter freundii, and Klebsiella pneumoniae and decreased the relative abundances of Lactobacillus reuteri and Lactobacillus murinus. The percentages of CD4+/CD8+ T cells and B cells in the spleen; the levels of interleukin-9 (IL-9), interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), IL-6, and IL-8 in the lung; and the level of mevalonolactone in plasma were increased in IAV-MRSA-coinfected mice. L. murinus was positively correlated with lung macrophages and natural killer (NK) cells, negatively correlated with spleen B cells and CD4+/CD8+ T cells, and correlated with multiple plasma metabolites. Future research is needed to clarify whether L. murinus mediates or alters the severity of IAV-MRSA coinfection. IMPORTANCE The respiratory microbiome plays an important role in respiratory tract infections. In this study, we characterized the URT and LRT microbiota, the host immune response, and plasma metabolic profiles during IAV-MRSA coinfection and evaluated their correlations. We observed that IAV-MRSA coinfection induced severe lung injury and dysregulated host immunity and plasma metabolic profiles, as evidenced by the aggravation of lung pathological damage, the reduction of innate immune cells, the strong adaptation of the immune response, and the upregulation of mevalonolactone in plasma. L. murinus was strongly correlated with immune cells and plasma metabolites. Our findings contribute to a better understanding of the role of the host microbiome in respiratory tract infections and identified a key bacterial species, L. murinus, that may provide important references for the development of probiotic therapies.

Effects of lactic acid bacteria isolated from Tibetan chickens on the growth performance and gut microbiota of broiler

Lactic acid bacteria (LAB) are organic supplements that have several advantages for the health of the host. Tibetan chickens are an ancient breed, which evolve unique gut microbiota due to their adaptation to the hypoxic environment of high altitude. However, knowledge of LAB isolated from Tibetan chickens is very limited. Thus, the purpose of this study was to assess the probiotic properties of Lactobacillus Plantarum (LP1), Weissella criteria (WT1), and Pediococcus pentosaceus (PT2) isolated from Tibetan chickens and investigate their effects on growth performance, immunoregulation and intestinal microbiome in broiler chickens. Growth performance, serum biochemical analysis, real-time PCR, and 16S rRNA sequencing were performed to study the probiotic effects of LP1, WT1, and PT2 in broiler chickens. Results showed that LP1, WT1 and PT2 were excellent inhibitors against Escherichia coli (E. coli ATCC25922), meanwhile, LP1, WT1, and PT2 significantly increased weekly weight gain, villus height, antioxidant ability and gut microbiota diversity indexes in broilers. In addition, LP1 and PT2 increased the relative abundance of Lactobacillus and decreased Desulfovibrio in comparison with T1 (control group). Additionally, oral LAB can reduce cholesterol and regulate the expression of tight junction genes in broiler chickens, suggesting that LAB can improve the integrity of the cecal barrier and immune response. In conclusion, LAB improved the growth performance, gut barrier health, intestinal flora balance and immune protection of broiler chickens. Our findings revealed the uniqueness of LAB isolated from Tibetan chickens and its potential as a probiotic additive in poultry field.

Combined Inhibition of the TGF-β1/Smad Pathway by Prevotella copri and Lactobacillus murinus to Reduce Inflammation and Fibrosis in Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic disease characterized by inflammation and fibrosis of the bile ducts. Cholestasis may lead to hepatic inflammation and fibrosis, and amelioration of cholestasis may allow recovery from inflammatory and fibrotic pathological damage. Prevotella copri (P. copri) interventions have been reported to significantly improve cholestasis and liver fibrosis in 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced PSC mouse models. Even though P. copri treatment alone cannot bring about recovery from DDC-induced inflammation, it increases the abundance of Lactobacillus murinus (L. murinus) compared with DDC treatment, which has been reported to have anti-inflammatory effects. The abundance of L. murinus still not recovering to a normal level may underlie hepatic inflammation in P. copri + DDC mice. Separate or combined interventions of P. copri and L. murinus were used to investigate the molecular mechanism underlying the improvement in PSC inflammation and fibrosis. P. copri and L. murinus significantly reduced the hepatic inflammatory cell aggregation and inflammatory factor expression as well as the hepatic collagen content and fibrin factor expression in the PSC mice. Further analysis of phosphorylation and dephosphorylation levels revealed that treating the PSC mice with the P. copri and L. murinus combined intervention inhibited the activity of the DDC-activated TGF-β1/Smad pathway, thereby reducing liver inflammation and fibrosis. The combination of P. copri and L. murinus inhibits the TGF-β1/Smad pathway and reduces inflammation and fibrosis in PSC.

Molecular Mechanisms and Pathophysiological Pathways of High-Fat Diets and Caloric Restriction Dietary Patterns on Pain

Pain perception provides evolutionary advantages by enhancing the probability of survival, but chronic pain continues to be a significant global health concern in modern society. Various factors are associated with pain alteration. Accumulating evidence has revealed that obesity correlates with enhanced pain perception, especially in chronic pain individuals. Existing dietary patterns related to obesity are primarily high-fat diets (HFD) and calorie restriction (CR) diets, which induce or alleviate obesity separately. HFD has been shown to enhance nociception while CR tends to alleviate pain when measuring pain outcomes. Herein, this review mainly summarizes the current knowledge of the effects of HFD and CR on pain responses and underlying molecular mechanisms of the immunological factors, metabolic regulation, inflammatory processes, Schwann cell (SC) autophagy, gut microbiome, and other pathophysiological signaling pathways involved. This review would help to provide insights on potential nonpharmacological strategies of dietary patterns in relieving pain.

Gut microbiome-mediated mechanisms in aging-related diseases: are probiotics ready for prime time?

Chronic low-grade inflammation affects health and is associated with aging and age-related diseases. Dysregulation of the gut flora is an important trigger for chronic low-grade inflammation. Changes in the composition of the gut flora and exposure to related metabolites have an effect on the inflammatory system of the host. This results in the development of crosstalk between the gut barrier and immune system, contributing to chronic low-grade inflammation and impairment of health. Probiotics can increase the diversity of gut microbiota, protect the gut barrier, and regulate gut immunity, thereby reducing inflammation. Therefore, the use of probiotics is a promising strategy for the beneficial immunomodulation and protection of the gut barrier through gut microbiota. These processes might positively influence inflammatory diseases, which are common in the elderly.

A nexus of dietary restriction and gut microbiota: Recent insights into metabolic health

In recent times, dietary restriction (DR) has received considerable attention for its promising effects on metabolism and longevity. Previous studies on DR have mainly focused on the health benefits produced by different restriction patterns, whereas comprehensive reviews of the role of gut microbiota during DR are limited. In this review, we discuss the effects of caloric restriction, fasting, protein restriction, and amino acid restriction from a microbiome perspective. Furthermore, the underlying mechanisms by which DR affects metabolic health by regulating intestinal homeostasis are summarized. Specifically, we reviewed the impacts of different DRs on specific gut microbiota. Additionally, we put forward the limitations of the current research and suggest the development of personalized microbes-directed DR for different populations and corresponding next-generation sequencing technologies for accurate microbiological analysis. DR effectively modulates the composition of the gut microbiota and microbial metabolites. In particular, DR markedly affects the rhythmic oscillation of microbes which may be related to the circadian clock system. Moreover, increasing evidence supports that DR profoundly improves metabolic syndrome, inflammatory bowel disease, and cognitive impairment. To summarize, DR may be an effective and executable dietary manipulation strategy for maintaining metabolic health, however, further investigation is needed to elucidate the underlying mechanisms.

Caloric restriction remodels the hepatic chromatin landscape and bile acid metabolism by modulating the gut microbiota

BACKGROUND

Caloric restriction (CR) has been known to promote health by reprogramming metabolism, yet little is known about how the epigenome and microbiome respond during metabolic adaptation to CR.

RESULTS

We investigate chromatin modifications, gene expression, as well as alterations in microbiota in a CR mouse model. Collectively, short-term CR leads to altered gut microbial diversity and bile acid metabolism, improving energy expenditure. CR remodels the hepatic enhancer landscape at genomic loci that are enriched for binding sites for signal-responsive transcription factors, including HNF4α. These alterations reflect a dramatic reprogramming of the liver transcriptional network, including genes involved in bile acid metabolism. Transferring CR gut microbiota into mice fed with an obesogenic diet recapitulates the features of CR-related bile acid metabolism along with attenuated fatty liver.

CONCLUSIONS

These findings suggest that CR-induced microbiota shapes the hepatic epigenome followed by altered expression of genes responsible for bile acid metabolism.

Whole organism aging: Parabiosis, inflammaging, epigenetics, and peripheral and central aging clocks. The ARS of aging

The strong interest shown in the study of the causes of aging in recent decades has uncovered many mechanisms that could contribute to the rate of aging. These include mitochondrial ROS production, DNA modification and repair, lipid peroxidation-induced membrane fatty acid unsaturation, autophagy, telomere shortening rate, apoptosis, proteostasis, senescent cells, and most likely there are many others waiting to be discovered. However, all these well-known mechanisms work only or mainly at the cellular level. Although it is known that organs within a single individual do not age at exactly the same rate, there is a well-defined species longevity. Therefore, loose coordination of aging rate among the different cells and tissues is needed to ensure species lifespan. In this article we focus on less known extracellular, systemic, and whole organism level mechanisms that could loosely coordinate aging of the whole individual to keep it within the margins of its species longevity. We discuss heterochronic parabiosis experiments, systemic factors distributed through the vascular system like DAMPs, mitochondrial DNA and its fragments, TF-like vascular proteins, and inflammaging, as well as epigenetic and proposed aging clocks situated at different levels of organization from individual cells to the brain. These interorgan systems can help to determine species longevity as a further adaptation to the ecosystem.

Calorie restriction ameliorates hyperglycemia, modulates the disordered gut microbiota, and mitigates metabolic endotoxemia and inflammation in type 2 diabetic rats

PURPOSE

The effects of calorie restriction (CR) on gut microbiota and the mechanism of CR ameliorating hyperglycemia in streptozotocin (STZ)-induced T2DM model rats were explored.

METHODS

High-fat diet and STZ injection were applied to induce T2DM model rats. Rats were divided into the following three groups: the control-diet ad libitum group, the T2DM model group fed with ad libitum diet, and the T2DM group fed with 30% restriction diet. 16S rRNA sequencing was used to determine the bacterial communities. Lipopolysaccharide (LPS)-binding protein (LBP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were measured.

RESULTS

Glucose tolerance and insulin sensitivity were improved by CR, as well as the levels of fasting and random plasma glucose. Besides, CR not only modulated the overall structure of gut microbiota but also had selective enrichment in anti-inflammatory bacteria such as Lachnospiraceae_NK4A136_group, Ruminococcaceae_9, Allobaculum, Alistipes, and Oscillibacter, and decreased pro-inflammatory pathogenic bacteria such as Bacteroides, Lachnoclostridium, and Bifidobacterium. Tax4Fun indicated that CR could regulate related functional pathways such as lipopolysaccharide biosynthesis, and the plasma levels of LBP, IL-6, and TNF-α were markedly reduced by CR, suggesting the mechanism of CR ameliorating hyperglycemia may associate with the modulation of disordered gut microbiota and the reduction of metabolic endotoxemia and inflammation.

CONCLUSION

CR could ameliorate hyperglycemia, the mechanism of which may associate with the alteration of the overall structure of gut microbiota, restoration of disordered microbiota function, and the downregulation of metabolic endotoxemia and inflammation in diabetic rats.

Amelioration of Colitis by a Gut Bacterial Consortium Producing Anti-Inflammatory Secondary Bile Acids

The Integrative Human Microbiome Project and other cohort studies have indicated that inflammatory bowel disease is accompanied by dysbiosis of gut microbiota, decreased production of secondary bile acids, and increased levels of primary bile acids. Secondary bile acids, such as ursodeoxycholic acid (UDCA) and lithocholic acid (LCA), have been reported to be anti-inflammatory, yet it remains to be studied whether introducing selected bacteria strains to restore bile acid metabolism of the gut microbiome can alleviate intestinal inflammation. In this study, we screened human gut bacterial strains for bile acid metabolism and designed a consortium of three species, including Clostridium AP sp000509125, Bacteroides ovatus, and Eubacterium limosum, and named it BAC (bile acid consortium). We showed that the three-strain gut bacterial consortium BAC is capable of converting conjugated primary bile acids taurochenodeoxycholic acid and glycochenodeoxycholic acid to secondary bile acids UDCA and LCA in vitro. Oral gavage treatment with BAC in mice resulted in protective effects against dextran sulfate sodium (DSS)-induced colitis, including reduced weight loss and increased colon length. Furthermore, BAC treatment increased the fecal level of bile acids, including UDCA and LCA. BAC treatment enhanced intestinal barrier function, which may be attributed to the increased activation of the bile acid receptor TGR5 by secondary bile acids. Finally, we examined the remodeling of gut microbiota by BAC treatment. Taken together, the three-strain gut bacterial consortium BAC restored the dysregulated bile acid metabolism and alleviated DSS-induced colitis. Our study provides a proof-of-concept demonstration that a rationally designed bacterial consortium can reshape the metabolism of the gut microbiome to treat diseases. IMPORTANCE Secondary bile acids have been reported to be anti-inflammatory, yet it remains to be studied whether introducing selected bacteria strains to restore bile acid metabolism of the gut microbiome can alleviate intestinal inflammation. To address this gap, we designed a consortium of human gut bacterial strains based on their metabolic capacity to produce secondary bile acids UDCA and LCA, and we evaluated the efficacy of single bacterial strains and the bacterial consortium in treating the murine colitis model. We found that oral gavage of the bacterial consortium to mice restored secondary bile acid metabolism to increase levels of UDCA and LCA, which induced the activation of TGR5 to improve gut-barrier integrity and reduced the inflammation in murine colitis. Overall, our study demonstrates that rationally designed bacterial consortia can reshape the metabolism of the gut microbiome and provides novel insights into the application of live biotherapeutics for treating IBD.

Heat-killed Lactobacillus murinus confers neuroprotection against dopamine neuronal loss by targeting NLRP3 inflammasome

The intestinal flora has become very active in studies related to Parkinson's disease (PD) in recent years. The microbe-gut-brain axis is closely related to the maintenance of brain homeostasis as well as PD pathogenesis. Alterations in gut bacteria can contribute to neuroinflammation and dopamine (DA) neurodegeneration. Lactobacillus murinus, a gram-positive bacterium, is a commensal gut bacteria present in the mammalian gut and considered as a potential probiotic due to its beneficial effects, including anti-inflammatory and antibacterial actions. In this study, the effects of live L. murinus and heat-killed L. murinus on DA neuronal damage in rats and the underlying mechanisms were investigated. Data showed that heat-killed L. murinus ameliorated 6-hydroxydopamine-induced motor dysfunctions and loss of substantia nigra DA neurons, while no protection was shown in live L. murinus treatment. At the same time, heat-killed L. murinus reduced the activation of NLRP3 inflammasome in microglia and the secretion of pro-inflammatory factors, thus inhibiting the development of neuroinflammation. Furthermore, heat-killed L. murinus failed to display its original neuroprotective properties in NLRP3 inflammasome knockout mice. Together, heat-killed L. murinus conferred neuroprotection against DA neuronal loss via the inhibition of microglial NLRP3 inflammasome activation. These findings provide a promising potential for future applications of L. murinus, and also beneficial strategy for PD treatment.

Impact of caloric restriction on the gut microbiota

Caloric restriction (CR) and related time-restricted diets have been popularized as means of preventing metabolic disease while improving general well-being. However, evidence as to their long-term efficacy, adverse effects, and mechanisms of activity remains incompletely understood. The gut microbiota is modulated by such dietary approaches, yet causal evidence to its possible downstream impacts on host metabolism remains elusive. Herein, we discuss the positive and adverse influences of restrictive dietary interventions on gut microbiota composition and function, and their collective impacts on host health and disease risk. We highlight known mechanisms of microbiota influences on the host, such as modulation of bioactive metabolites, while discussing challenges in achieving mechanistic dietary-microbiota insights, including interindividual variability in dietary responses as well as other methodological and conceptual challenges. In all, causally understanding the impact of CR approaches on the gut microbiota may enable to better decode their overall influences on human physiology and disease.

Fecal Microbiota, Forage Nutrients, and Metabolic Responses of Horses Grazing Warm- and Cool-Season Grass Pastures

Integrating warm-season grasses into cool-season equine grazing systems can increase pasture availability during summer months. The objective of this study was to evaluate effects of this management strategy on the fecal microbiome and relationships between fecal microbiota, forage nutrients, and metabolic responses of grazing horses. Fecal samples were collected from 8 mares after grazing cool-season pasture in spring, warm-season pasture in summer, and cool-season pasture in fall as well as after adaptation to standardized hay diets prior to spring grazing and at the end of the grazing season. Random forest classification was able to predict forage type based on microbial composition (accuracy: 0.90 ± 0.09); regression predicted forage crude protein (CP) and non-structural carbohydrate (NSC) concentrations (p < 0.0001). Akkermansia and Clostridium butyricum were enriched in horses grazing warm-season pasture and were positively correlated with CP and negatively with NSC; Clostridum butyricum was negatively correlated with peak plasma glucose concentrations following oral sugar tests (p ≤ 0.05). These results indicate that distinct shifts in the equine fecal microbiota occur in response different forages. Based on relationships identified between the microbiota, forage nutrients, and metabolic responses, further research should focus on the roles of Akkermansia spp. and Clostridium butyricum within the equine hindgut.

Vaginal microbial dynamics and pathogen colonization in a humanized microbiota mouse model

Vaginal microbiota composition is associated with differential risk of urogenital infection. Although vaginal Lactobacillus spp. are thought to confer protection through acidification, bacteriocin production, and immunomodulation, lack of an in vivo model system that closely resembles the human vaginal microbiota remains a prominent barrier to mechanistic discovery. We performed 16S rRNA amplicon sequencing of wildtype C57BL/6J mice, commonly used to study pathogen colonization, and found that the vaginal microbiome composition varies highly both within and between colonies from three distinct vivaria. Because of the strong influence of environmental exposure on vaginal microbiome composition, we assessed whether a humanized microbiota mouse ( HMb mice) would model a more human-like vaginal microbiota. Similar to humans and conventional mice, HMb mice vaginal microbiota clustered into five community state types ( h mCST). Uniquely, HMb mice vaginal communities were frequently dominated by Lactobacilli or Enterobacteriaceae . Compared to genetically-matched conventional mice, HMb mice were less susceptible to uterine ascension by urogenital pathobionts group B Streptococcus (GBS) and Prevotella bivia , but no differences were observed with uropathogenic E. coli . Specifically, vaginal Enterobacteriaceae and Lactobacillus were associated with the absence of uterine GBS. Anti-GBS activity of HMb mice vaginal E. coli and L. murinus isolates, representing Enterobacteriaceae and Lactobacillus respectively, were characterized in vitro and in vivo . Although L. murinus reduced GBS growth in vitro , vaginal pre-inoculation with HMb mouse-derived E. coli , but not L. murinus , conferred protection against vaginal GBS burden. Overall, the HMb mice are an improved model to elucidate the role of endogenous microbes in conferring protection against urogenital pathogens.

IMPORTANCE

An altered vaginal microbiota, typically with little to no levels of Lactobacillus , is associated with increased susceptibility to urogenital infections, although mechanisms driving this vulnerability are not fully understood. Despite known inhibitory properties of Lactobacillus against urogenital pathogens, clinical studies with Lactobacillus probiotics have shown mixed success. In this study, we characterize the impact of the vaginal microbiota on urogenital pathogen colonization using a humanized microbiota mouse model that more closely mimics the human vaginal microbiota. We found several vaginal bacterial taxa that correlated with reduced pathogen levels but showed discordant effects in pathogen inhibition between in vitro and in vivo assays. We propose that this humanized microbiota mouse platform is an improved model to describe the role of the vaginal microbiota in protection against urogenital pathogens. Furthermore, this model will be useful in testing efficacy of new probiotic strategies in the complex vaginal environment.

Dietary patterns and cardiometabolic health: Clinical evidence and mechanism

For centuries, the search for nutritional interventions to underpin cardiovascular treatment and prevention guidelines has contributed to the rapid development of the field of dietary patterns and cardiometabolic disease (CMD). Numerous studies have demonstrated that healthy dietary patterns with emphasis on food-based recommendations are the gold standard for extending lifespan and reducing the risks of CMD and mortality. Healthy dietary patterns include various permutations of energy restriction, macronutrients, and food intake patterns such as calorie restriction, intermittent fasting, Mediterranean diet, plant-based diets, etc. Early implementation of healthy dietary patterns in patients with CMD is encouraged, but an understanding of the mechanisms by which these patterns trigger cardiometabolic benefits remains incomplete. Hence, this review examined several dietary patterns that may improve cardiometabolic health, including restrictive dietary patterns, regional dietary patterns, and diets based on controlled macronutrients and food groups, summarizing cutting-edge evidence and potential mechanisms for CMD prevention and treatment. Particularly, considering individual differences in responses to dietary composition and nutritional changes in organ tissue diversity, we highlighted the critical role of individual gut microbiota in the crosstalk between diet and CMD and recommend a more precise and dynamic nutritional strategy for CMD by developing dietary patterns based on individual gut microbiota profiles.

Gut Lactobacillus and Probiotics Lactobacillus lactis/rhamnosis Ameliorate Liver Fibrosis in Prevention and Treatment

The progression and exacerbation of liver fibrosis are closely related to the gut microbiome. It is hypothesized that some probiotics may slow the progression of liver fibrosis. In human stool analysis [healthy group (n = 44) and cirrhosis group (n = 18)], difference in Lactobacillus genus between healthy group and cirrhosis group was observed. Based on human data, preventive and therapeutic effect of probiotics Lactobacillus lactis and L. rhamnosus was evaluated by using four mice fibrosis models. L. lactis and L. rhamnosus were supplied to 3,5-diethoxycarbonyl-1,4-dihydrocollidine or carbon tetrachloride-induced liver fibrosis C57BL/6 mouse model. Serum biochemical measurements, tissue staining, and mRNA expression in the liver were evaluated. The microbiome was analyzed in mouse cecal contents. In the mouse model, the effects of Lactobacillus in preventing and treating liver fibrosis were different for each microbe species. In case of L. lactis, all models showed preventive and therapeutic effects against liver fibrosis. In microbiome analysis in mouse models administered Lactobacillus, migration and changes in the ratio and composition of the gut microbial community were confirmed. L. lactis and L. rhamnosus showed preventive and therapeutic effects on the progression of liver fibrosis, suggesting that Lactobacillus intake may be a useful strategy for prevention and treatment.

Screening and Characterization of Pediococcus acidilactici LC-9-1 toward Selection as a Potential Probiotic for Poultry with Antibacterial and Antioxidative Properties

Growing interest has been focused on lactic acid bacteria as alternatives to antimicrobial growth promoters, which are characterized by the production of various functional metabolites, such as antimicrobial and antioxidants compounds. The present study was undertaken to evaluate a potential probiotic from the antioxidant perspective. LC-9-1, screened from the intestines of healthy animals, was revealed to be Pediococcus acidilactici on the basis of its morphological, biochemical, and molecular characteristics. The strain has excellent properties, including acid-production efficiency, antibacterial performance and antioxidant activity. The safety of the strain was also evaluated. Furthermore, the experiments in broiler chickens suggested that dietary LC-9-1 supplementation improved the growth performance and decreased the abdominal fat, and enhanced the antioxidant capability and intestinal innate immunity of broilers. Analysis of intestinal microbiota showed that a higher community diversity (Shannon index) was achieved. In addition to the significantly increased relative abundances of Pediococcus spp., beneficial genera such as Rothia spp. and Ruminococcus spp. were abundant, while opportunistic pathogens such as Escherichia-Shigella spp. were significantly reduced in LC-9-1-supplemented broilers. Collectively, such in-depth characterization and the available data will guide future efforts to develop next-generation probiotics, and LC-9-1 could be considered a potential strain for further utilization in direct-fed microbial or starter culture for fermentation.

Topography of respiratory tract and gut microbiota in mice with influenza A virus infection

Introduction

Influenza A virus (IAV)-induced dysbiosis may predispose to severe bacterial superinfections. Most studies have focused on the microbiota of single mucosal surfaces; consequently, the relationships between microbiota at different anatomic sites in IAV-infected mice have not been fully studied.

Methods

We characterized respiratory and gut microbiota using full-length 16S rRNA gene sequencing by Nanopore sequencers and compared the nasopharyngeal, oropharyngeal, lung and gut microbiomes in healthy and IAV-infected mice.

Results

The oropharyngeal, lung and gut microbiota of healthy mice were dominated by Lactobacillus spp., while nasopharyngeal microbiota were comprised primarily of Streptococcus spp. However, the oropharyngeal, nasopharyngeal, lung, and gut microbiota of IAV-infected mice were dominated by Pseudomonas, Escherichia, Streptococcus, and Muribaculum spp., respectively. Lactobacillus murinus was identified as a biomarker and was reduced at all sites in IAV-infected mice. The microbiota composition of lung was more similar to that of the nasopharynx than the oropharynx in healthy mice.

Discussion

These findings suggest that the main source of lung microbiota in mice differs from that of adults. Moreover, the similarity between the nasopharyngeal and lung microbiota was increased in IAV-infected mice. We found that IAV infection reduced the similarity between the gut and oropharyngeal microbiota. L. murinus was identified as a biomarker of IAV infection and may be an important target for intervention in post-influenza bacterial superinfections.

Based on 16 S rRNA sequencing and metabonomics to reveal the new mechanism of aluminum potassium sulfate induced inflammation and abnormal lipid metabolism in mice

More and more discoveries have been made about the chronic toxic effects of aluminum, but the specific mechanism of action remains unclear. In this study, we explored the perturbation of aluminum on intestinal microflora and its effects on host and microbial metabolites through a more realistic nutrient absorption model. The microorganisms Turicibacter, Lactobacillus murinus, Lactobacillus_reuteri and Bifidobacterium pseudolongum may be the main targets of the aluminum affecting microbiota. Lysine, proline, putrescine, serotonin and cholesterol may be important metabolites affected by aluminum ions after the interference of intestinal flora composition, leading to abnormal metabolism pathways of amino acids and lipids in the body, and thus promoting inflammation and lesion. The possible mechanisms of aluminum action on the body: (1) Affecting immune cell response, ROS generation and production of a series of pro-inflammatory factors to promote inflammation; (2) Through the disturbance of intestinal microbiota composition structure, change the abundance of metabolites, and then affect amino acid metabolism, lipid metabolism pathways. The joint analysis of multiple omics showed significant difference in microbiome abundance and metabolomics expression between high dose group and the control group.

High-protein diet prevents fat mass increase after dieting by counteracting Lactobacillus-enhanced lipid absorption

Dietary restriction is widely used to reduce fat mass and lose weight in individuals with or without obesity; however, weight regain after dieting is still a big challenge, and the underlying mechanisms remain largely elusive. Here we show that refeeding after various types of dieting induces quick fat accumulation in mice and enhanced intestinal lipid absorption contributes to post-dieting fat mass increase. Moreover, refeeding after short-term dietary restriction is accompanied by an increase in intestinal Lactobacillus and its metabolites, which contributes to enhanced intestinal lipid absorption and post-dieting fat mass increase; however, refeeding a high-protein diet after short-term dietary restriction attenuates intestinal lipid absorption and represses fat accumulation by preventing Lactobacillus growth. Our results provide insight into the mechanisms underlying fat mass increase after dieting. We also propose that targeting intestinal Lactobacillus to inhibit intestinal lipid absorption via high-protein diet or antibiotics is likely an effective strategy to prevent obesity after dieting.

Hedgehog blockade remodels the gut microbiota and the intestinal effector CD8+ T cells in a mouse model of mammary carcinoma

Given the gut microbiome's rise as a potential frontier in cancer pathogenesis and therapy, leveraging microbial analyses in the study of breast tumor progression and treatment could unveil novel interactions between commensal bacteria and disease outcomes. In breast cancer, the Hedgehog (Hh) signaling pathway is a potential target for treatment due to its aberrant activation leading to poorer prognoses and drug resistance. There are limited studies that have investigated the influences of orally administered cancer therapeutics, such as Vismodegib (a pharmacological, clinically used Hh inhibitor) on the gut microbiota. Using a 4T1 mammary carcinoma mouse model and 16 S rRNA sequencing, we longitudinally mapped alterations in immunomodulating gut microbes during mammary tumor development. Next, we identified changes in the abundance of commensal microbiota in response to Vismodegib treatment of 4T1 mammary tumor-bearing mice. In addition to remodeling gut microbiota, Vismodegib treatment elicited an increase in proliferative CD8⁺ T cells in the colonic immune network, without any remarkable gastrointestinal-associated side effects. To our knowledge, this is the first study to assess longitudinal changes in the gut microbiome during mammary tumor development and progression. Our study also pioneers an investigation of the dynamic effects of an orally delivered Hh inhibitor on the gut microbiome and the gut-associated immune-regulatory adaptive effector CD8⁺ T cells. These findings inform future comprehensive studies on the consortium of altered microbes that can impact potential systemic immunomodulatory roles of Vismodegib.