Lachnospiraceae NK4A136 Group Research Articles

Higher mucosal type II immunity is associated with increased gut microbiota diversity in BALB/c mice after Trichinella spiralis infection

Understanding the interaction between the gut microbiota and Trichinella spiralis is of interest for the early diagnosis and development of therapeutics for trichinellosis and to reveal the potential role of microbiota in the mechanism of immunomodulation of this tissue-dwelling helminth. In this study, we utilized 16S rRNA gene sequencing to monitor the dynamics of the microbes in BALB/c mice challenged with T. spiralis. Flow cytometry and ELISA were used to analyze cytokines at the same time. Histopathological analysis of the duodenum was also conducted. We found that microbial perturbations occurred during infection. The abundance of the Lachnospiraceae NK4A136 group, Ruminococcus 1 and Lactococcus decreased. However, the abundance of proinflammatory Parabacteroides increased over time after infection. T. spiralis infection also tended to inhibit IFN-γ production, and promote IL-4 and IL-10 levels. In total, T. spiralis disrupts gut homeostasis and impairs the development of the intestinal ecosystem. Defining the bacterial populations affected by T. spiralis infection might help identify microbial markers for diagnosis of the disease, and the populations could also be further exploited as a novel option to treat T. spiralis infection.

Prenatal opioid administration induces shared alterations to the maternal and offspring gut microbiome: A preliminary analysis

Background While many studies have described the impact of prenatal opioid exposure on development, possible mechanisms for how opioids exert developmental impairments remain elusive. Emerging evidence indicates disruptions in the maternal gut microbiome can alter offspring development; however, no studies to date have examined the impact of maternal opioid treatment on maternal-offspring microbiome dysbiosis. Methods A mouse model of prenatal methadone exposure (PME) was employed to assess the impact of maternal opioid treatment on the microbiome of methadone-treated dams (MD) and their offspring. Fecal samples were collected from dams (n = 8 per treatment), one male and one female offspring per dam (n = 8 offspring per sex per treatment) for 16S rRNA sequencing. Results Methadone treatment significantly increased the microbial diversity and led to an expansion in family level bacterial abundance. Correlational analysis revealed significant positive associations between dam and offspring measures of diversity indicating methadone-induced shifts in the microbial communities are shared between dam and offspring. Sixteen features in dams and 10 features in offspring were significantly differentially abundant between treatment groups with many features corresponding to the Lachnospiraceae NK4A136 genus. Of the six features identified as differentially abundant in both MD and PME offspring, all were assigned to the Lachnospiraceae NK4A136 group, and the abundances demonstrated strong positive correlations between dam and offspring. Conclusions These preliminary findings indicate that maternal opioid treatment during pregnancy alters the composition of the maternal microbiome, and this opioid-induced shift is similarly observed in offspring which could contribute to the impaired developmental phenotypes previously described.

Abstract 72: Bifidobacterium longum RAPO enhances efficacy of anti-PD-1 immunotherapy in a mouse model of triple-negative breast cancer

Abstract Background: Triple negative breast cancer (TNBC) represents approximately 15-20% of all breast cancers and 35% of breast cancer death. TNBC has a highly aggressive behavior with the increased risk of early metastasis and relapse and poor survival rate. Given that TNBC is associated with higher levels of tumor-infiltrating lymphocytes and programmed cell death ligand 1 (PD-L1), immune checkpoint inhibitors (ICI) are considered as the appropriate treatment of patients with TNBC. However, it has been reported that ICI monotherapy is less effective compared with combination therapy. Recent several studies suggest that gut microbiome plays a critical role in the efficacy of ICI therapy. Thus, we investigated the effects of Bifidobacterium longum RAPO supplementation on anti-PD-1 therapy against TNBC and the underlying mechanisms in vivo. Methods: The 4T1 murine metastatic breast cancer cells were injected s.c into the flank of female BALB/c mice. When tumors reached 50-150 mm3, mice were randomly assigned to one of four groups; tumor control (TC), Anti-PD-1, B. longum RAPO (RAPO), or Anti-PD-1+RAPO (n=10 per group). Anti-PD-1 antibody was injected i.p. 5 times at 3 day intervals. B. longum RAPO was orally administered daily from 2 days before the first injection of anti-PD-1. Spleen and tumor tissues were analyzed by flow cytometry, qRT-PCR, and immunohistochemistry, and fecal samples were collected for 16S rRNA gene sequencing. Results: On day 12, tumor volume was significantly inhibited in Anti-PD-1+RAPO group compared with TC and Anti-PD-1 groups. Higher levels of PD-L1 IHC score and PD-L1 mRNA expression were observed in tumor tissues of Anti-PD-1+RAPO group. Anti-PD-1+RAPO group was also associated with the increased levels of spleen NKT cells and tumor NK cells. The proportion of pro-tumor M2 macrophages and M2/M1 ratio were significantly decreased in tumor tissues of Anti-PD-1+RAPO group than those of Anti-PD-1 group. Similarly, combination therapy of Anti-PD-1 with RAPO significantly reduced mRNA expression of M2 markers such as IL10 and Arg1, while it augmented that of anti-tumor cytokines including IFNγ and TNFα compared with Anti-PD-1 treatment alone. In addition, the relative abundance of the genus Bifidobacterium was remarkably enriched in Anti-PD-1+RAPO group compared with other groups. In Anti-PD-1+RAPO group, the relative abundance of the genus Akkermansia and Lachnospiraceae NK4A136 group were significantly increased after administration for 2 weeks. Conclusions: Our data suggests that combination therapy of B. longum RAPO with anti-PD-1 modulates anti-tumor immunity and gut microbiota, contributing to the better response to anti-PD-1 immunotherapy in mice with TNBC. This study provides evidence that B. longum RAPO might be a potential candidate for immunomodulatory pharmabiotics in cancer immunotherapy. Citation Format: Hyeyoon Kim, Rira Oh, Sangjun Park, Geun Eog Ji, Myeong Soo Park, Sung-Eun Kim. Bifidobacterium longum RAPO enhances efficacy of anti-PD-1 immunotherapy in a mouse model of triple-negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 72.

Comparative study of growth performance, nutrient digestibility, and ruminal and fecal bacterial community between yaks and cattle-yaks raised by stall-feeding

The experiment was conducted to compare the growth performance, rumen fermentation, nutrient digestibility, and ruminal and fecal bacterial community between yaks and cattle-yaks. Ten male yaks (36-month-old) were used as the yak (YAK) group and 10 male cattle-yaks with similar age were selected as the cattle-yak (CAY) group. All the animals were fed same ration and the experiment lasted for 60 days. The results showed that the average daily gain and dry matter intake of CAY group were higher (P < 0.05) than those of YAK group. The ruminal concentrations of total volatile fatty acids, acetate, and butyrate were higher (P < 0.05) in CAY group than those in YAK group. However, the neutral detergent fiber and acid detergent fiber digestibility exhibited an opposite between two groups. In the rumen, the relative abundances of Prevotella 1 and Prevotellaceae UCG-001 were higher (P < 0.05) and Succiniclasticum and Butyrivibrio 2 were lower (P < 0.05) in YAK group compared to CAY group. In the feces, the unclassified Lachnospiraceae, Lachnospiraceae NK4A136 group, and Lachnospiraceae AC2044 group were significantly enriched (P < 0.05) in YAK group, whereas the Ruminococcaceae UCG-010, Ruminococcaceae UCG-013, and Succiniclasticum were significantly enriched (P < 0.05) in CAY group. Overall, under the same diet, the yaks have higher fiber utilization and cattle-yaks have higher energy utilization.

Fermentation outcomes of wheat cell wall related polysaccharides are driven by substrate effects as well as initial faecal inoculum

Potentially beneficial microorganisms in the human gut microbiota may be promoted through exploiting dietary fibre (DF) characteristics. Wheat flour cell walls (WCW) are compositionally diverse and architecturally complex. Arabinoxylan (AX), mixed-linkage (1,3), (1,4)-β-glucan (MLG) and cellulose are the major components of WCW. This study investigated fermentation of WCW, individual polysaccharide components (AX, MLG and cellulose), and a physical mixture of them (Mix), using human faecal inoculum. Interestingly, the substrate order of final gas production and the degradation patterns of each were comparable to previous porcine faecal fermentation results, pointing to the important influence of substrate properties on fermentation outcomes. However, the human faecal fermentation was faster, with higher amounts of propionate and less n-butyrate produced than from the corresponding substrate fermented by porcine faecal inoculum. Microbiota variation during polysaccharide degradation were determined, and associations were made with fermentation end-products: Coprococcus 3, Bifidobacterium and Lachnospiraceae ND3007 group were positively correlated with AX fermentation and acetate production, while Catenibacterium and Lachnospiraceae NK4A136 group appeared to contribute to MLG degradation and n-butyrate production. These findings suggest that the nature of DF primarily dictates the relative extent of fermentation, while the fermentation rate, end-product composition and microbial shifts are more linked with specific microbial activity of individual bacterial groups, dependent on the initial microbiota composition.

Combination Therapy of Bifidobacterium longum RAPO With Anti-PD-1 Treatment Enhances Anti-tumor Immune Response in Association With Gut Microbiota Modulation

ObjectivesTriple negative breast cancer (TNBC) has a poor prognosis with a high risk of metastasis and relapse, and accounts for approximately 35% of breast cancer death. Immune checkpoint inhibitors (ICI) have been in the spotlight recently as a novel treatment of TNBC due to the higher expressions of programmed cell death ligand 1 (PD-L1) and tumor-infiltrating lymphocytes in TNBC. Considering that gut microbiome is associated with immune response and ICI efficacy, we investigated whether Bifidobacterium longum RAPO supplementation would affect the efficacy of anti-PD-1 therapy against TNBC in vivo. MethodsFemale BALB/c mice bearing 4T1 breast cancer cells were randomly divided into four groups; tumor control (TC), Anti-PD-1, B. longum RAPO (RAPO), or Anti-PD-1 + RAPO (Combi). Anti-PD-1 antibody was injected i.p. 5 times at 3-day intervals and B. longum RAPO was orally administered daily from 2 days before the first injection of anti-PD-1. Spleen and tumor tissues were analyzed by flow cytometry, IHC, and qRT-PCR. Fecal samples were analyzed by 16S rRNA gene sequencing. ResultsTumor volume was reduced in the Combi group than TC and Anti-PD-1 groups on day 12. PD-L1 IHC score and PD-L1 mRNA expression were significantly increased in tumors of the Combi group. The levels of the spleen CD8/CD4 ratio and tumor NK cells were also increased in the Combi group. Compared with the Anti-PD-1 group, the pro-tumor M2 macrophages and related cytokines (IL10, Arg1) were significantly decreased, while anti-tumor M1 cytokines (IFNγ, TNFα) were elevated in tumors of the Combi group. Consistently, immunogenic cell death-associated markers were significantly higher in the Combi group. We found that the relative proportion of the genus Bifidobacterium, Lachnoclostridium, Lachnospiraceae NK4A136 group, and Clostridium sensu stricto 1, which are known to be associated with the better response to ICI therapy, were significantly increased, while the genus Mucispirillum and Dubosiella were decreased in the Combi group than the Anti-PD-1 group. ConclusionsOur data indicates that combination therapy of B. longum RAPO with anti-PD-1 enhances anti-tumor immune response in association with modulation of gut microbiota, suggesting that B. longum RAPO might be a potential candidate for pharmabiotics in ICI treatment. Funding SourcesBIFIDO CO, the National Research Foundation of Korea grant.

Effect of Vitamin A Supplementation on Growth Performance, Serum Biochemical Parameters, Intestinal Immunity Response and Gut Microbiota in American Mink (Neovison vison).

Simple SummaryVitamin A is critical throughout life, but utilization of vitamin A often results in local and systemic toxicity. This study investigated the effect of vitamin A supplementation on mink growth and health. The results show that vitamin A deficiency decreased the ADG, villus height, villus height/crypt depth ratio and mRNA expression levels of IL-22, Occludin and ZO-1. Vitamin A supplementation increased the diversity of jejunum bacteria, decreased the ratio of Firmicutes to Bacteroidetes and increased the relative abundance of Akkermansia and Lachnospiraceae NK4A136 group.This experiment investigated the effect of vitamin A supplementation on growth, serum biochemical parameters, jejunum morphology and the microbial community in male growing-furring mink. Thirty healthy male mink were randomly assigned to three treatment groups, with 10 mink per group. Each mink was housed in an individual cage. The mink in the three groups were fed diets supplemented with vitamin A acetate at dosages of 0 (CON), 20,000 (LVitA) and 1,280,000 IU/kg (HVitA) of basal diet. A 7-day pretest period preceded a formal test period of 45 days. The results show that 20,000 IU/kg vitamin A increased the ADG, serum T-AOC and GSH-Px activities, villus height and villus height/crypt depth ratio (p < 0.05). The mRNA expression levels of IL-22, Occludin and ZO-1 in the jejunum of mink were significantly higher in the LVitA group than those in the CON and HVitA groups (p < 0.05). Vitamin A supplementation increased the diversity of jejunum bacteria, decreased the ratio of Firmicutes to Bacteroidetes and increased the relative abundance of Akkermansia, uncultured bacterium f Muribaculaceae, Allobaculum, Lachnospiraceae NK4A136 group, Rummeliibacillus and Parasutterella. The comparison of potential functions also showed enrichment of glycan biosynthesis and metabolism, transport and catabolism pathways in the vitamin A supplementation groups compared with the CON group. In conclusion, these results indicate that dietary vitamin A supplementation could mediate host growth by improving intestinal development, immunity and the relative abundance of the intestinal microbiota.

Integrated gut microbiota and fecal metabolomics reveal the renoprotective effect of Rehmanniae Radix Preparata and Corni Fructus on adenine-induced CKD rats

Rehmanniae Radix Preparata (RR) and Corni Fructus (CF), well-known traditional Chinese medicines (TCMs), were generally used together in the clinical practices to treat chronic kidney disease (CKD) with synergistic effects for thousands of years, but their combination mechanism remains largely unknown so far. Recent evidences have implicated intestinal flora as potential targets for the therapy of CKD. In this study, the CKD rat model was induced by adenine. The levels of proteinuria, serum creatine (SCr), blood urea nitrogen (BUN) and creatinine clearance (Ccr) were used to assess the cooperation effect of RR and CF. Furthermore, high-throughput 16S ribosomal RNA (rRNA) gene sequencing combined with fecal metabonomics based on UPLC-Q-TOF-MS/MS were applied to explore the variations of intestinal flora and their metabolic profiles. 16S rRNA gene sequencing data indicated that CKD rats treated with RR, CF and RC showed the differences in the composition of gut microbiota. The abundance of beneficial bacteria including Ruminococcaceae UCG-014, Ruminococcus 1, Prevotellaceae_NK3B31_group, Lachnospiraceae NK4A136 group and Lachnospiraceae UCG-001 were elevated in various degrees, while the opportunistic pathogen such as Desulfovibrio was markedly decreased after the treatment. Moreover, fecal metabolite profiles revealed 15 different metabolites associated with CKD. These metabolites were mainly involved in the related metabolic pathways such as amino acid metabolism, bile acids metabolism and glycerophospholipid metabolism. The results implied that gut flora and their metabolites might play a vital role in the progress of CKD, which provided a potential target for the development of novel drugs for the therapy of CKD.

Microbiome Markers of Pancreatic Cancer Based on Bacteria-Derived Extracellular Vesicles Acquired from Blood Samples: A Retrospective Propensity Score Matching Analysis.

Simple SummaryAlthough tremendous advances in diagnosis and treatment, pancreatic cancer still remains one of the lethal diseases with an overall survival rate of 10~15%. Early detection and diagnosis of pancreatic cancer is very important in improving the prognosis of patients. The aim of our study was to find new biomarkers, using microbiomes based on bacteria-derived extracellular vesicles, extracted from blood serum. With 38 patients with pancreatic cancer and 52 healthy controls with no history of pancreatic disease, we identified several compositional differences of microbiome between them. Using various combinations of the metagenomic markers which made the compositional differences, we also built a pancreatic cancer prediction model with high area under the receiver operating characteristic curve (0.966 at the phylum level and 1.000 at the genus level). These microbiome markers, based on bacteria-derived extracellular vesicles acquired from blood, show demonstrate the potential of candidate biomarkers for early diagnosis of pancreatic cancer.Novel biomarkers for early diagnosis of pancreatic cancer (PC) are necessary to improve prognosis. We aimed to discover candidate biomarkers by identifying compositional differences of microbiome between patients with PC (n = 38) and healthy controls (n = 52), using microbial extracellular vesicles (EVs) acquired from blood samples. Composition analysis was performed using 16S rRNA gene analysis and bacteria-derived EVs. Statistically significant differences in microbial compositions were used to construct PC prediction models after propensity score matching analysis to reduce other possible biases. Between-group differences in microbial compositions were identified at the phylum and genus levels. At the phylum level, three species (Verrucomicrobia, Deferribacteres, and Bacteroidetes) were more abundant and one species (Actinobacteria) was less abundant in PC patients. At the genus level, four species (Stenotrophomonas, Sphingomonas, Propionibacterium, and Corynebacterium) were less abundant and six species (Ruminococcaceae UCG-014, Lachnospiraceae NK4A136 group, Akkermansia, Turicibacter, Ruminiclostridium, and Lachnospiraceae UCG-001) were more abundant in PC patients. Using the best combination of these microbiome markers, we constructed a PC prediction model that yielded a high area under the receiver operating characteristic curve (0.966 and 1.000, at the phylum and genus level, respectively). These microbiome markers, which altered microbial compositions, are therefore candidate biomarkers for early diagnosis of PC.

Colonization Dynamics of Multidrug-Resistant Klebsiella pneumoniae Are Dictated by Microbiota-Cluster Group Behavior over Individual Antibiotic Susceptibility: A Metataxonomic Analysis.

Gastrointestinal carriage of multidrug-resistant (MDR) bacteria is one of the main risk factors for developing serious, difficult-to-treat infections. Given that there is currently no all-round solution to eliminate colonization with MDR bacteria, it is particularly important to understand the dynamic process of colonization to aid the development of novel decolonization strategies. The aim of our present study was to perform metataxonomic analyses of gut microbiota dynamics during colonization with an extended-spectrum β-lactamase (ESBL)- and carbapenemase-producing Klebsiella pneumoniae (ECKP) strain in mice; additionally, to ascertain the effects of antibiotic administration (ampicillin, ceftazidime, and ciprofloxacin) on the establishment and elimination of ECKP intestinal colonization. We have found that the phyla Bacteroidetes and Firmicutes were most dominant in all of the treatment groups; however, Bacteroidetes was more common in the groups treated with antibiotics compared to the control group. Significant differences were observed among the different antibiotic-treated groups in beta but not alpha diversity, implying that the difference is the relative abundance of some bacterial community members. Bacteria from the Lachnospiraceae family (including Agathobacter, Anaerostipes, Lachnoclostridium 11308, Lachnospiraceae UCG-004, Lachnospiraceae NK3A20 group 11318, Lachnospiraceae NK4A136 group 11319, Roseburia, and Tyzzerella) showed an inverse relationship with the carriage rate of the ECKP strain, whereas members of Enterobacteriaceae and the ECKP strain have shown a correlational relationship. Our results suggest that the composition of the microbial community plays a primary role in the MDR-colonization rate, whereas the antibiotic susceptibility of individual MDR strains affects this process to a lesser extent. Distinct bacterial families have associated into microbial clusters, collecting taxonomically close species to produce survival benefits in the gut. These associations do not develop at random, as they may be attributed to the presence of specific metabolomic networks. A new concept should be introduced in designing future endeavors for MDR decolonization, supplemented by knowledge of the composition of the host bacterial community and the identification of bacterial clusters capable of suppressing or enhancing the invader species.

RSPO4-CRISPR alleviates liver injury and restores gut microbiota in a rat model of liver fibrosis

Wnt signaling dysfunction and gut dysbiosis may lead to liver fibrosis, yet the underlying mechanisms are not well elucidated. This study demonstrated the role of RSPO4, a Wnt signaling agonist, in liver fibrogenesis and its impact on the gut microbiome. RSPO4 gene in CCl4-induced fibrotic-liver rats was knockout by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) system, with healthy rats served as the control. Tissue samples and hepatic stellate cells (HSCs) isolated from rats were examined for curative effect of RSPO4-CRISPR treatment. Fecal sample were collected and analyzed with 16 S rRNA sequencing. We found RSPO4-CRISPR relieved liver fibrosis in rats and reversed HSC activation. Further, results showed RSPO4-CRISPR tended to restore the microflora composition. Significance species between groups were identified. Bacteroides and Escherichia-Shigella were the key microbes in the model and negative group, whereas Lactobacillus, Romboutsia, and Lachnospiraceae NK4A136 group were abundant in the control. Notably, Bacteroidales S24-7 group and Ruminococcaceae UCG-005 were the significantly enriched in CRISPR group. We show that the microbiome of rats treated with RSPO4-CRISPR presents a trend towards the restoration of the original condition. Our findings pave a new way to evaluate the curative effect of liver fibrosis treatment.

Casein-fed mice showed faster recovery from DSS-induced colitis than chicken-protein-fed mice.

This study aimed to examine whether casein- and chicken protein-fed mice had different capacities of recovering from dextran sulfate sodium (DSS)-induced colitis. Mice were fed a chicken protein or casein diet for 14 days, which was followed by 7-day DSS treatment and then a 6-day recovery period by gavage of Akkermansia muciniphila (A. muciniphila). Compared with the chicken protein diet, the casein diet increased the relative abundance of beneficial gut bacteria, whereas DSS treatment did not induce significant differences in physiological and pathological indicators between the diet groups. During the recovery period, gavage of A. muciniphila alleviated colitis symptoms by decreasing the score of the disease activity index (DAI), spleen weight, and TNF-α mRNA level but increasing the mucus thickness and MUC2 mRNA level. Several genera, including the Ruminococcaceae NK4A214 group, Bifidobacterium, Roseburia, Ruminiclostridium and Lachnospiraceae NK4A136 group, may play a critical role. In addition, the casein diet helped DSS-treated mice recover faster from colitis, in terms of their body weight, colon length and histological score, probably due to its higher digestibility.

Maternal Gestational &lt;i&gt;Bifidobacterium bifidum&lt;/i&gt; TMC3115 Treatment Shapes Construction of Offspring Gut Microbiota and Development of Immune System and Induces Immune Tolerance to Food Allergens

Background: Our previous studies has proved that Bifidobacterium bifidum TMC3115 (TMC3115) treatment during infancy could protect neonates from adulthood allergy. However, whether it could still protect offspring from allergic diseases when treatment during maternal pregnancy and the underlying mechanisms remain unclear. Methods: Pregnant BALB/c mice were gavaged with TMC3115 until delivery. Offspring were reared until weaning (postnatal day 21, PND21) and then sensitized with ovalbumin (OVA) until PND49. Vaginal, gut, and breast milk microbiota were sequenced. Immunoglobulin and cytokines, splenic and colonic gene expressions, and fecal short chain fatty acids (SCFAs) were measured. Findings: After maternal TMC3115 treatment, the microbiota of maternal breast milk from newborn offspring and gut microbiota of neonates and at weaning were changed the most, and levels of serum and breast milk immunoglobulin and of splenic cytokines as well as mRNA expression of colonic intestinal development indicators were all significantly altered in offspring in different stages. Synchronous changes in the specific microbiota were found in the maternal gut, vagina, and breast milk and in the offspring gut microbiota, such as Proteobacteria. After sensitization with OVA, there was no significant change in levels of serum IgE or OVA-specific IgE/IgG1 in the offspring in TMC3115 group; however, IgM, expression of colonic Ki67, Muc2, and tight junction proteins and production of fecal SCFAs were significantly increased as were the relative abundances of Lactobacillus and Lachnospiraceae NK4A136 group. Interpretation: Our results suggested that the day of birth and weaning were the important “window of opportunity” for neonatal gut microbiota construction and that maternal treatment with TMC3115 could play a profound modulatory effect on the development of the immune system in offspring at different stages. Maternal TMC3115 treatment may induce immune tolerance to allergens in OVA-stimulated offspring and enhance intestinal tissue development and barrier function and primary immune response to allergens through modulating gut microbiota and SCFA production. Funding Information: This work was supported by the National Natural Science Foundation of China (Grant number: 81372982). Declaration of Interests: The authors declare that they have no conflict of interest. Ethics Approval Statement: The animal experiment facility and animals used for the present study were officially approved by the Experimental Animal Management Committee of Sichuan Government. Experimental protocols were approved by the West China School of Public Health Medical Ethics Committee of Sichuan University (Approved number: SYXK2018-011).

Ligustrum robustum (Roxb.) blume extract modulates gut microbiota and prevents metabolic syndrome in high-fat diet-fed mice

Ethnopharmacological relevanceIn Chinese folk medicine, Ligustrum robustum (Roxb.) Blume has been widely used as a healthy tea beverage for improvement in obesity and lipidemic metabolic disorders.Aim of the study: We aimed to investigate the effect of L. robustum extract (LRE) on metabolic syndrome in high-fat diet (HFD)-fed mice and to explore the underlying role of gut microbiota during the treatment. Materials and methodsThe ground dried leaves of L. robustum (Roxb.) Blume were extracted with ethanol and then purified by a resin column. The composition of L. robustum extract (LRE) was analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). C57BL/6 J mice fed with HFD were treated with LRE for 16 weeks. RT-qPCR and morphological staining were utilized to reveal the impact of LRE on hepatic glucolipid metabolism and gut integrity. The next-generation sequencing of 16 S rDNA was applied for analyzing the gut microbial community of fecal samples. ResultsLRE, mainly composed of ligupurpuroside A and aceteoside, alleviated insulin resistance, improved hepatic metabolism, enhanced intestinal integrity, and suppressed inflammatory responses in HFD-fed mice. Moreover, LRE treatment reshaped the gut microbiota structure by increasing the levels of genera Streptococcus, Lactobacillus, and Mucispirillum and decreasing the populations of Alistipes and Lachnospiraceae NK4A136 group in HFD-fed mice. The alteration of gut microbiota was associated with several metabolic pathways of gut bacteria. Spearman's correlation analysis further confirmed the links between the changed intestinal bacteria and multiple disease indices. ConclusionsLRE prevented gut microbiota dysbiosis and metabolic disorder in HFD-fed mice, which helps to promote the application in LRE-mediated prevention from metabolic syndrome as a gut microbial regulator.

Spermidine improves gut barrier integrity and gut microbiota function in diet-induced obese mice

ABSTRACT Obesity is associated with impaired intestinal barrier function and dysbiosis of the gut microbiota. Spermidine, a polyamine that acts as an autophagy inducer, has important benefits in patients with aging-associated diseases and metabolic dysfunction. However, the mechanism of spermidine on obesity remains unclear. Here, we show that spermidine intake is negatively correlated with obesity in both humans and mice. Spermidine supplementation causes a significant loss of weight and improves insulin resistance in diet-induced obese (DIO) mice. These effects are associated with the alleviation of metabolic endotoxemia and enhancement of intestinal barrier function, which might be mediated through autophagy pathway and TLR4-mediated microbial signaling transduction. Moreover, spermidine causes the significant alteration of microbiota composition and function. Microbiota depletion compromises function, while transplantation of spermidine-altered microbiota confers protection against obesity. These changes might partly be driven by an SCFA-producing bacterium, Lachnospiraceae NK4A136 group, which was decreased in obese subjects and subsequently increased by spermidine. Notably, the change of Lachnospiraceae NK4A136 group is significantly correlated with enhanced gut barrier function induced by spermidine. Our results indicate that spermidine supplementation may serve as a viable therapy for obesity.

Shengmai Yin formula modulates the gut microbiota of spleen-deficiency rats

BackgroundSpleen-deficiency syndrome, an important pathological change in traditional Chinese medicine, has been proven to attribute to intestinal dysbacteriosis. Shengmai Yin (SMY), a classic formula for replenishing qi and restoring pulse, is a common medicine for critical emergencies in traditional Chinese Medicine. Interestingly, our previous study established a spleen-deficiency rat model and verified the potency of SMY formula in curing spleen-deficiency rats. Our goal herein was to explore whether SMY can modulate the composition of intestinal flora and alleviate spleen-deficiency in rats.MethodsThis experiment was randomly divided into three groups, namely the normal control group (NC), model control group (MC), and the Shengmai Yin group (SMY). After the treatment, the weight and symptom indexes of the rats were recorded, histological changes in the colon were observed, levels of serum D-xylose, gastrin (GAS), and vasoactive intestinal peptide (VIP) were measured, and gut microbiota profiling was conducted by 16S rRNA sequencing.ResultsThe body mass of the spleen-deficiency model rats significantly decreased compared with that of the NC group, and SMY treatment significantly increased body mass compared with the MC group (P < 0.01). Colon histopathology revealed that SMY treatment alleviated colonic mucosal damage in spleen-deficiency rats. The serum levels of D-xylose and gastrin (GAS) were significant increased by SMY (P < 0.05, P < 0.01), and vasoactive intestinal peptide (VIP) was reduced by SMY (P < 0.01) compared with MC. Furthermore, alpha diversity was significantly decreased in the model rats compared to the normal rats (P < 0.05) and increased with SMY treatment (P < 0.01). The most abundant phyla were Firmicutes and Bacteroidetes, followed by Proteobacteria, Verrucomicrobia, and Actinobacteria. At the genus level, there was a lower relative abundance of Lactobacillus, Bacteroides, Akkermasia, and Allobaculum, and a higher relative abundance of Lachnospiraceae NK4A 136 group, Ruminococcaceae UCG-014, and Sphingomonas in the MC group. The relative abundance of Actinobacteria, Alistipes, Bifidobacterium, Bifidobacterium, Bifidobacteriaceae, Lachnospiraceae NK4A136group, Lactobacillus, Lactobacillaceae, Bacilli, Verrucomicrobiae, and Akkermansia were significantly abundant in the treatment groups, and thus may be singled out as potential biomarkers for SMY in the treatment of spleen deficiency. In addition, analysis on the correlation between species and physicochemical indexes showed that the abundance of Parasutterella was negatively correlated with the change in GAS, and positively correlated with the change in VIP (P < 0.01).ConclusionOur findings have provided preliminary evidence that modulating the gut microbiota may play a role in the treatment of spleen deficiency with SMY. However, further studies are needed to clarify the mechanism by which SMY regulation of related gut microbiota occurs.

Alterations of Gut Microbiome and Metabolite Profiling in Mice Infected by Schistosoma japonicum.

Schistosoma japonicum (S. japonicum) is one of the etiological agents of schistosomiasis, a widespread zoonotic parasitic disease. However, the mechanism of the balanced co-existence between the host immune system and S. japonicum as well as their complex interaction remains unclear. In this study, 16S rRNA gene sequencing, combined with metagenomic sequencing approach as well as ultraperformance liquid chromatography–mass spectrometry metabolic profiling, was applied to demonstrate changes in the gut microbiome community structure during schistosomiasis progression, the functional interactions between the gut bacteria and S. japonicum infection in BALB/c mice, and the dynamic metabolite changes of the host. The results showed that both gut microbiome and the metabolites were significantly altered at different time points after the infection. Decrease in richness and diversity as well as differed composition of the gut microbiota was observed in the infected status when compared with the uninfected status. At the phylum level, the gut microbial communities in all samples were dominated by Firmicutes, Bacteroidetes, Proteobacteria, and Deferribacteres, while at the genus level, Lactobacillus, Lachnospiraceae NK4A136 group, Bacteroides, Staphylococcus, and Alloprevotella were the most abundant. After exposure, Roseburia, and Ruminococcaceae UCG-014 decreased, while Staphylococcus, Alistipes, and Parabacteroides increased, which could raise the risk of infections. Furthermore, LEfSe demonstrated several bacterial taxa that could discriminate between each time point of S. japonicum infection. Besides that, metagenomic analysis illuminated that the AMP-activated protein kinase (AMPK) signaling pathway and the chemokine signaling pathway were significantly perturbed after the infection. Phosphatidylcholine and colfosceril palmitate in serum as well as xanthurenic acid, naphthalenesulfonic acid, and pimelylcarnitine in urine might be metabolic biomarkers due to their promising diagnostic potential at the early stage of the infection. Alterations of glycerophospholipid and purine metabolism were also discovered in the infection. The present study might provide further understanding of the mechanisms during schistosome infection in aspects of gut microbiome and metabolites, and facilitate the discovery of new targets for early diagnosis and prognostic purposes. Further validations of potential biomarkers in human populations are necessary, and the exploration of interactions among S. japonicum, gut microbiome, and metabolites is to be deepened in the future.

Lactose-Induced Chronic Diarrhea Results From Abnormal Luminal Microbial Fermentation and Disorder of Ion Transport in the Colon.

Diarrhea is one of the major abdominal symptoms in lactose-intolerant subjects. The changes in the large intestinal luminal environment and disorder of the epithelial ion transport in lactose-induced diarrhea remain unclear. The present study aimed to investigate the effect of an incremental high-lactose diet (IHLD, 30%/40%/50%) on luminal microbiota, microbiota-derived metabolite concentrations and colonic ion transport. Gut microbiota were analyzed by 16S rRNA amplicon sequencing and the concentration of SCFAs by gas chromatography, galactose, lactose and lactic acid through assay kit; Ussing chamber was performed to detect basal and stimulated ion transport; The expression and location of SCFA transporters, the Na-H exchanger 3(NHE3), cystic fibrosis transporter regulater (CFTR) and NKCC1 in the colon mucosa were analyzed by western and immunostaining. The concentrations of lactose, galactose and lactic acid of the cecal content were markedly increased (P < 0.01) and SCFA concentration was significantly decreased (P < 0.01). This was associated with depletion of the Lachnospiraceae NK4A136 group and Ruminococcaceae UCG-005 and increased relative abundance of Lactobacillus, escherichia-shigella and megamonas in the cecal microbiota. The expression of monocarboxylate transporter 1 was decreased in the colonic mucosa of the IHLD group. Low NHE3 expression and phosphorylation levels, and decreases in delta basal short circuit current after apical Na+ removal in the colonic mucosa of the IHLD group contributed to Na+ accumulation in the lumen and decrease stimulated Cl– secretion with low CFTR and NKCC1 expression would compensate for water and electrolyte loss during the diarrhea process. These results indicated that the persistence of the diarrhea state was maintained by abnormal colonic microbiota fermentation leading to high concentrations of lactose, galactose and lactic acid and low SCFAs in the lumen, and decreased Na+ absorption with the low NHE3 expression and phosphorylation levels.

Dysbiosis, gut barrier dysfunction and inflammation in dementia: a pilot study

BackgroundDementia is an increasing public health threat worldwide. The pathogenesis of dementia has not been fully elucidated yet. Inflammatory processes are hypothesized to play an important role as a driver for cognitive decline but the origin of inflammation is not clear. We hypothesize that disturbances in gut microbiome composition, gut barrier dysfunction, bacterial translocation and resulting inflammation are associated with cognitive dysfunction in dementia.MethodsTo test this hypothesis, a cohort of 23 patients with dementia and 18 age and sex matched controls without cognitive impairments were studied. Gut microbiome composition, gut barrier dysfunction, bacterial translocation and inflammation were assessed from stool and serum samples. Malnutrition was assessed by Mini Nutritional Assessment Short Form (MNA-SF), detailed information on drug use was collected. Microbiome composition was assessed by 16S rRNA sequencing, QIIME 2 and Calypso 7.14 tools.ResultsDementia was associated with dysbiosis characterized by differences in beta diversity and changes in taxonomic composition. Gut permeability was increased as evidenced by increased serum diamine oxidase (DAO) levels and systemic inflammation was confirmed by increased soluble cluster of differentiation 14 levels (sCD14). BMI and statin use had the strongest impact on microbiome composition.ConclusionDementia is associated with changes in gut microbiome composition and increased biomarkers of gut permeability and inflammation. Lachnospiraceae NK4A136 group as potential butyrate producer was reduced in dementia. Malnutrition and drug intake were factors, that impact on microbiome composition. Increasing butyrate producing bacteria and targeting malnutrition may be promising therapeutic targets in dementia.Trial registrationNCT03167983.

Sodium Butyrate Alleviates Mouse Colitis by Regulating Gut Microbiota Dysbiosis.

Simple SummaryInflammatory bowel disease (IBD) is extremely harmful to animal health and can affect animal growth and production. Dextran sulfate sodium (DSS) can cause IBD in animals, resulting in diarrhea and bloody stools. The present study aimed to determine whether oral sodium butyrate can relieve DSS-induced colitis in mice. By using histological evaluation (H&E) staining technology and 16S rRNA sequence analysis, we found that the severity of colitis in mice receiving oral sodium butyrate was reduced, and the composition of gut microbiota was changed. These results indicate that sodium butyrate can relieve DSS-induced colitis in mice by restoring the balance of gut microbiota dysbiosis.Inflammatory bowel disease (IBD) develops as a result of complicated interactions between genetic susceptibility, excessive innate immunity, and environmental factors, which are mainly related to the gut microbiota. The present study aimed to elucidate the protective effects and underlying mechanisms of a short-chain fatty acid salt, sodium butyrate, on colonic inflammation induced by dextran sulfate sodium (DSS) in mice. Pretreatment with sodium butyrate attenuated colitis, as demonstrated by the decreased disease activity index (DAI), colon length shortening, spleen tumidness, and histopathology scores, while maintaining intestinal barrier integrity, as observed by H&E staining and electron microscopy. 16S rRNA sequence analysis revealed that sodium butyrate caused a remarkable alteration of the gut microbiota. Bacteroides, Lachnospiraceae, the Lachnospiraceae NK4A136 group, and Ruminiclostridium 6 presented dramatic differences after sodium butyrate supplementation. This work verifies that sodium butyrate can improve mouse colitis via microbe–host interactions by regulating the microbial community. Taken together, the findings demonstrate that sodium butyrate shows great potential as a probiotic agent for ameliorating colitis.