Imbalance In Gut Microbiome Research Articles

Changes to Gut Microbiota Following Systemic Antibiotic Administration in Infants.

Long-term antibiotic use can have consequences on systemic diseases, such as obesity, allergy, and depression, implicating the causal role of gut microbiome imbalance. However, the evaluation of the effect of antibiotics in early infancy on alterations to the gut microbiome remains poorly understood. This study aimed to evaluate the gut microbiome state in infancy following systemic antibiotic treatment. Twenty infants under 3 months of age who had received antibiotics for at least 3 days were enrolled, and their fecal samples were collected 4 weeks after antibiotic administration finished. Thirty-four age-matched healthy controls without prior exposure to antibiotics were also assessed. The relative bacterial abundance in feces was obtained via sequencing of 16 S rRNA genes, and alpha and beta diversities were evaluated. At the genus level, the relative abundance of Escherichia/Shigella and Bifidobacterium increased (p = 0.03 and p = 0.017, respectively) but that of Bacteroides decreased (p = 0.02) in the antibiotic treatment group. The microbiome of the antibiotic treatment group exhibited an alpha diversity lower than that of the control group. Thus, systemic antibiotic administration in early infancy affects the gut microbiome composition even after a month has passed; long-term studies are needed to further evaluate this.

Gut microbiota and plasma cytokine levels in patients with attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is a common childhood mental disorder with undetermined pathophysiological mechanisms. The gut microbiota and immunological dysfunction may influence brain functions and social behaviours. In the current study, we aimed to explore the correlation of gut microbiome imbalance and inflammation in the pathophysiology of ADHD. Forty-one children with ADHD and thirty-nine healthy-control (HC) individuals were recruited. Faecal samples from all participants were collected and submitted for 16 S rRNA V3–V4 amplicon microbiome sequencing analysis. The plasma levels of 10 cytokines, including TNF-α, IL-6, IL-1β, IL-2, IL-10, IL-13, IL-17A, IFN-α2, IFN-γ, and MCP-1, were determined using a custom-made sandwich enzyme-linked immunosorbent assay (ELISA) developed by Luminex Flowmetrix. There was no significant difference between the ADHD and HC groups in species diversity in the faeces, as determined with α-diversity and β-diversity analysis. In the ADHD group, three differentially abundant taxonomic clades at the genus level were observed, namely Agathobacter, Anaerostipes, and Lachnospiraceae. Top differentially abundant bacteria and representative biological pathways were identified in children with ADHD using linear discriminant analysis (LDA) effect size (LEfSe), and the phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) analysis, respectively. The plasma levels of TNF-α were significantly lower in children with ADHD than in HCs. Within the ADHD group, the levels of TNF-α were negatively correlated with ADHD symptoms and diversity of the gut microbiome. Our study provides new insights into the association between gut microbiome dysbiosis and immune dysregulation, which may contribute to the pathophysiology of ADHD.

Abstract MP228: The Role Of Gut Microbiome Secreted Short Chain Fatty Acids In The Development Of Heart Failure With Preserved Ejection Fraction HFpEF

More than 50% of patients with heart failure are diagnosed with heart failure with preserved ejection fraction (HFpEF), and 80% of them are obese. It is a prominent disease with no available treatments. It is characterized by diastolic dysfunction that involves increase in left ventricle stiffness and decrease in its relaxation during diastole. To better understand the pathogenesis of obesity associated HFpEF, our studies focus on the early asymptomatic changes in cardiac mechanics that occurs before the increases in intracardiac pressure. Therefore, we have developed an obesity associated mouse model that we called pre-HFpEF where mice were fed either Normal Chow or Western Diet for 14 weeks. Our echocardiography measurements indicated the presence of early cardiac dysfunction consistent with obesity associated pre-HFpEF phenotype. Mice on WD had decrease in Global Longitudinal Strain (%GLS) and Longitudinal strain rate reverse (LSRr) indicating early signs of systolic and diastolic dysfunction, as well as increase in left ventricle anterior and posterior wall thickness during diastole (LVAWd, LVPWd). Obesity is also known to cause microbiome imbalance, which plays a significant role in the development of cardiovascular diseases through changes in short chains fatty acids, which are products of dietary fiber fermentation by the gut bacteria. In order to study the association between gut microbiome imbalance and HFpEF development, we treated our obese pre-HFpEF mice with fecal matter transplantation (FMT) from either lean or obese mice, and we found that FMT from lean mice led to significant improvements in systolic and diastolic dysfunction by increasing %GLS and LSRr and preventing hypertrophy by decreasing LVAWd and LVPWd. In addition, WD reduced butyrate producing bacteria, however circulating levels of butyrate were significantly increased with lean FMT treatment. Using an in-vitro approach to mimic WD we found butyrate treatment to inhibit the activation of NLRP3 inflammasome and NF-KB. Therefore, since FMT treatment improved cardiac dysfunction in obesity associated pre-HFpEF mice, and that butyrate is increased after FMT and can play a role in metabolic homeostasis, we predict that butyrate could be an important player in FMT improvements through cardiac metabolic regulation and cardiac inflammation suppression

Unique Gut Microbiome in HIV Patients on Antiretroviral Therapy (ART) Suggests Association with Chronic Inflammation.

ABSTRACTChronic inflammation is a hallmark of human immunodeficiency virus (HIV) infection and a risk factor for the development and progression of age-related comorbidities. Although HIV-associated gut dysbiosis has been suggested to be involved in sustained chronic inflammation, there remains a limited understanding of the association between gut dysbiosis and chronic inflammation during HIV infection. Here, we investigated compositional changes in the gut microbiome and its role in chronic inflammation in patients infected with HIV. We observed that the gut microbiomes of patients with low CD4 counts had reduced alpha diversity compared to those in uninfected controls. Following CD4 recovery, alpha diversity was restored, but intergroup dissimilarity of bacterial composition remained unchanged between patients and uninfected controls. Patients with HIV had higher abundance of the classes Negativicutes, Bacilli, and Coriobacteriia, as well as depletion of the class Clostridia. These relative abundances positively correlated with inflammatory cytokines and negatively correlated with anti-inflammatory cytokines. We found that gut dysbiosis accompanying HIV infection was characterized by a depletion of obligate anaerobic Clostridia and enrichment of facultative anaerobic bacteria, reflecting increased intestinal oxygen levels and intestinal permeability. Furthermore, it is likely that HIV-associated dysbiosis shifts the immunological balance toward inflammatory Th1 responses and encourages proinflammatory cytokine production. Our results suggest that gut dysbiosis contributes to sustaining chronic inflammation in patients with HIV infection despite effective antiretroviral therapy and that correcting gut dysbiosis will be effective in improving long-term outcomes in patients.IMPORTANCE Chronic inflammation is a hallmark of HIV infection and is associated with the development and progression of age-related comorbidities. Although the gastrointestinal tract is a major site of HIV replication and CD4+ T-cell depletion, the role of HIV-associated imbalance of gut microbiome in chronic inflammation is unclear. Here, we aimed to understand the causal relationship between abnormalities in the gut microbiome and chronic inflammation in patients with HIV. Our results suggest HIV-associated gut dysbiosis presents a more aerobic environment than that of healthy individuals, despite prolonged viral suppression. This dysbiosis likely results from a sustained increase in intestinal permeability, which supports sustained bacterial translocation in HIV patients, despite effective therapy. Additionally, we observed that several bacterial taxa enriched in HIV patients were associated with increased expression of inflammatory cytokines. Collectively, these results suggest that gut dysbiosis plays an important role in chronic inflammation in HIV patients.

Association of Fusobacterium nucleatum infection and colorectal cancer: A Mexican study

Introduction and aimsColorectal cancer (CRC) is the third most prevalent cancer worldwide. Many risk factors are involved, and current evidence links the gut microbiota and colorectal carcinogenesis. Fusobacterium nucleatum (F. nucleatum) is proposed as one of the risk factors at the onset and during the progression of CRC, due to immune system and inflammatory modulation. Materials and methodsNinety samples from three different regions of the colon were collected through colonoscopy in patients with CRC, and qPCR TagMan® was conducted to detect F. nucleatum and cytokines (IL-17, IL-23, and IL-10) in tumor, peritumor, and normal samples. The differences between them were analyzed and correlated. ResultsThe abundance of F. nucleatum determined through the 2-ΔΔCt method in CRC (7.750 [5.790-10.469]) was significantly higher than in the normal control (0.409 [0.251-0.817]) (p < 0.05). There was no significant association between F. nucleatum and the cytokines (p > 0.05). ConclusionsCRC is a heterogeneous disease that presents and progresses in a complex microenvironment, partially due to gut microbiome imbalance. F. nucleatum was enriched in CRC tissue, but whether that is a cause of the pathology or a consequence, has not yet been clearly defined.

Gut microbiome-host interactions in driving environmental pollutant trichloroethene-mediated autoimmunity

Trichloroethene (TCE), a widely used industrial solvent, is associated with the development of autoimmune diseases (ADs), including systemic lupus erythematosus and autoimmune hepatitis. Increasing evidence support a linkage between altered gut microbiome composition and the onset of ADs. However, it is not clear how gut microbiome contributes to TCE-mediated autoimmunity, and initial triggers for microbiome-host interactions leading to systemic autoimmune responses remain unknown. To achieve this, female MRL+/+ mice were treated with 0.5 mg/ml TCE for 52 weeks and fecal samples were subjected to 16S rRNA sequencing to determine the microbiome composition. TCE exposure resulted in distinct bacterial community revealed by β-diversity analysis. Notably, we observed reduction in Lactobacillaceae, Rikenellaceae and Bifidobacteriaceae families, and enrichment of Akkermansiaceae and Lachnospiraceae families after TCE exposure. We also observed significantly increased colonic oxidative stress and inflammatory markers (CD14 and IL-1β), and decreased tight junction proteins (ZO-2, occludin and claudin-3). These changes were associated with increases in serum antinuclear and anti-smooth muscle antibodies and cytokines (IL-6 and IL-12), together with increased PD1 + CD4+ T cells in TCE-exposed spleen and liver tissues. Importantly, fecal microbiota transplantation (FMT) using feces from TCE-treated mice to antibiotics-treated mice induced increased anti-dsDNA antibodies and hepatic CD4+ T cell infiltration in the recipient mice. Our studies thus delineate how imbalance in gut microbiome and mucosal redox status together with gut inflammatory response and permeability changes could be the key factors in contributing to TCE-mediated ADs. Furthermore, FMT studies provide a solid support to a causal role of microbiome in TCE-mediated autoimmunity.

Luminescent Phage-Based Detection of Klebsiella pneumoniae: From Engineering to Diagnostics.

Bacteriophages (“phages”) infect and multiply within specific bacterial strains, causing lysis of their target. Due to the specific nature of these interactions, phages allow a high-precision approach for therapy which can also be exploited for the detection of phage-sensitive pathogens associated with chronic diseases due to gut microbiome imbalance. As rapid phage-mediated detection assays becoming standard-of-care diagnostic tools, they will advance the more widespread application of phage therapy in a precision approach. Using a conventional method and a new cloning approach to develop luminescent phages, we engineered two phages that specifically detect a disease-associated microbial strain. We performed phage sensitivity assays in liquid culture and in fecal matrices and tested the stability of spiked fecal samples stored under different conditions. Different reporter gene structures and genome insertion sites were required to successfully develop the two nluc-reporter phages. The reporter phages detected spiked bacteria in five fecal samples with high specificity. Fecal samples stored under different conditions for up to 30 days did not display major losses in reporter-phage-based detection. Luminescent phage-based diagnostics can provide a rapid co-diagnostic tool to guide the growing field of phage therapy, particularly for a precision-based approach to chronic diseases treatment.

Probiotics: An Update to Past Researches

Probiotics are beneficial bacteria living in the microbiota ecosystem of the human body playing particular important roles in human health. The increasing rate of various diseases and the studies about the balance of gut microbiome made scientists trying to find novel therapies in this regard and hypothesize the relationships between the imbalance of gut microbiome and spread of various diseases especially in the immune system. Previous studies have indicated that when administrated in specific amounts, probiotics exert beneficial properties for human health such as antibacterial effects, cytotoxic effects, Hypocholesterolemic effects, immunomodulatory effects, wound healing effects etc. Probiotics also are known to produce nourishing healthy supplements for the human body such as vitamin K and B as well as healthy fatty acids. In this regard summarization of scientific evidence may help to familiarize the scientists with this novel area of research helping to find effective therapies for various disease. In this study, we used published literature in scientific databases such as Web of Science, Cochrane Library, Medline, PubMed, Science Direct, Scopus, as well as Google Scholar for data collection. So, the present review describes scientific-based evidence about probiotics and some of their beneficial effects to highlight the path for further researches about these beneficial bacteria.

Abstract 3349: Evolution of the gut Amicrobiome during the pathogenesis of smoking-associated Kras-mutant lung cancer

Abstract Relative to other tumors in smokers, KRAS-mutant lung adenocarcinomas (LUADs) display dismal prognosis warranting the need for early management of this disease. Limiting these advances is our gap in knowledge of events that drive KRAS-mutant LUAD oncogenesis. Host defense systems, such as those elicited by the gut microbiome, were recently shown to influence tumors external to the gastrointestinal tract (e.g. melanomas), thus highlighting the microbiome as an orchestrator of oncogenesis. Yet, gut microbiome changes in early stages of KRAS-mutant LUAD development are not known. We recently reported that mice with knockout of G-protein coupled receptor 5A (Gprc5a-/-), in contrast to wild type (WT) littermates, develop LUADs which are accelerated following exposure to tobacco carcinogen (nicotine-specific nitrosamine ketone/NNK). LUADs in the tobacco exposed Gprc5a-/- mouse model exhibit high somatic mutation burdens, driver Kras variants and other co-occurring drivers, features constituting a “perfect storm” for LUAD pathogenesis in smokers. Using this human-relevant model, we performed 16S-Seq of fecal samples collected prior to and at several time points post-NNK exposure during LUAD development. We found significant, some progressive, microbial changes during the pathogenesis of LUAD, including abolishment of phylum Verrucomicrobia, progressive increase in tumor-promoting genera Odoribacter spp., gradual decrease in Akkermansia spp., which was previously shown to be associated with response to PD-1 blockade, as well as reduced abundance of Ruminococcus which was previously reported to be suppressed during colon carcinogenesis. Additionally, and prior to tumor onset, lungs and immune cells of these Gprc5a-/- mice exhibited markedly elevated expression of lipocalin 2 (LCN2), an antimicrobial protein released from host cells during microbiome imbalance and inflammation. We further found that Gprc5a-/- mice with knockout of Lcn2 exhibited increased tumors compared to similarly exposed Gprc5a-/- with intact Lcn2. These effects were accompanied by widespread changes in the gut microbiome including increased abundance of tumor-promoting Alistipes spp. and, conversely, reduced abundance of Lactobacillus spp. Our data show that host defense mediated by LCN2 counteracts Kras-mutant LUAD development by restricting gut microbiome imbalance (i.e., maintaining gut microbiome homeostasis and diversity), suggesting a protective role during Kras-mutant LUAD development. Our overall findings inform on novel pathways implicating antimicrobial host defense mechanisms in the development of smoking-associated Kras-mutant LUAD. Efforts are underway to discern specific microbiome profiles that are likely causally related to smoking-associated Kras-mutant LUAD development as well as to develop and test preclinical microbiome intervention strategies for this malignancy. Citation Format: Warapen Treekitkarnmongkol, Casey Finnicum, Ansam Sinjab, Maya Hassane, Christel Davis, Gareth E. Davies, Kristi L. Hoffman, Junya Fujimoto, Florencia McAllister, Boris Sepesi, Tina Cascone, Robert R. Jenq, Joseph Petrosino, Erik Ehli, Seyed J. Moghaddam, Humam Kadara. Evolution of the gut microbiome during the pathogenesis of smoking-associated Kras-mutant lung cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3349.

Gut Microbiome Alterations Precede Cerebral Amyloidosis and Microglial Pathology in a Mouse Model of Alzheimer's Disease.

Emerging evidence suggests that the gut microbiome actively regulates cognitive functions and that gut microbiome imbalance is associated with Alzheimer's disease (AD), the most prevalent neurodegenerative disorder. However, the changes in gut microbiome composition in AD and their association with disease pathology, especially in the early stages, are unclear. Here, we compared the profiles of gut microbiota between APP/PS1 transgenic mice (an AD mouse model) and their wild-type littermates at different ages by amplicon-based sequencing of 16S ribosomal RNA genes. Microbiota composition started diverging between the APP/PS1 and wild-type mice at young ages (i.e., 1–3 months), before obvious amyloid deposition and plaque-localized microglial activation in the cerebral cortex in APP/PS1 mice. At later ages (i.e., 6 and 9 months), there were distinct changes in the abundance of inflammation-related bacterial taxa including Escherichia-Shigella, Desulfovibrio, Akkermansia, and Blautia in APP/PS1 mice. These findings suggest that gut microbiota alterations precede the development of key pathological features of AD, including amyloidosis and plaque-localized neuroinflammation. Thus, the investigation of gut microbiota might provide new avenues for developing diagnostic biomarkers and therapeutic targets for AD.

Relationship between the Gut Microbiome and Energy/Nutrient Intake in a Confined Bioregenerative Life Support System.

Recent studies have suggested that the gut microbiome is modified in space analogs and that human health can be affected during actual spaceflight. However, the relationship between the gut microbiome and dietary intake in simulator subjects and astronauts remains unclear. Bioregenerative life support systems (BLSSs) are confined and self-sufficient ecosystems that enable exploration of this issue. Here, we correlate changes in gut microbes to the nutrient types present in controlled diets within subjects cohabitating in a BLSS. A metagenome-wide association study (MWAS) was performed on 55 shotgun-sequenced fecal samples longitudinally obtained from healthy Chinese subjects (n = 4 in total, n = 2 per sex) subjected to a 60-day BLSS stay and a specialized diet. Each food item was categorized based on nutrient type according to the Chinese Food Ingredients List (https://wenku.baidu.com/view/3f2b628488eb172ded630b1c59eef8c75fbf9514.html?from=search). The physical parameters of each subject fluctuated within normal medical ranges. Sex- and individual-specific differences and a trend of individual convergence of the gut microbiome in the BLSS were observed. Depletion of bacterial taxa such as Faecalibacterium prausnitzii, Bifidobacterium longum, and Escherichia coli and functional modules such as short-chain fatty acid (SCFA) production, as well as an increase in an unidentified Lachnospiraceae and glutamate/tryptophan synthesis, were observed in the BLSS. Correlation analysis showed that these compositional and functional changes were associated with energy/nutrient intake during the BLSS stay. Our findings suggest that the gut microbiota is a useful indicator for monitoring health and that individual nutritive diets should be considered according to sex and individual differences in simulations or in spaceflight.IMPORTANCE The gut microbiome shows individual specificity and is affected by sex, environment, and diet; gut microbiome imbalance is related to cancer, cardiovascular diseases, and autoimmune diseases. Astronauts are faced with a challenging environment and limited diet in outer space. Recent studies indicate that the gut microbiome is altered in space simulators and space, but what happens to intestinal microorganisms when astronauts cohabitate in a self-sufficient ecosystem in which they plant and cook food is unclear. Bioregenerative life support systems (BLSSs) are ideal devices to investigate the above issues because they are closed and self-sufficient. Four healthy Chinese subjects cohabitated in a confined BLSS for 60 days, during which their physical parameters and energy/nutrient intake were recorded. We performed a metagenome-wide association study (MWAS) on 55 shotgun-sequenced fecal samples longitudinally obtained from the subjects. Alterations occurred in the gut microbial composition and function, and their relationships with energy/nutrient intake were explored.

Lactobacillus plantarum SN13T Cells Improve Hepatic Dysfunction And Fecal Microbiota: A Randomized Pilot Study

The liver dysfunction is a worldwide health problem. It has been suggested that an imbalance of gut microbiome is associated with a variety of diseases. The goal of the present clinical trial is to evaluate the effectiveness of Lactobacillus plantarum SN13T on hepatic function and fecal microbiota. This study enrolled 22 subjects, aged between 20 and 70 years, and who had any of the following conditions: 40<AST<100 U/L, 40<ALT<100 U/L, or 70<γ-GTP<210 U/L for males; 30<γ-GTP<90 U/L for females. The subjects were assigned to the live or heat-killed SN13T group. The intake period was 16 weeks followed by an 8-week follow-up period. Although no difference was observed between the two groups in the changes of AST, ALT, and γ-GTP, the subgroup analyses of subjects with over a certain level at baseline showed significant decreases in AST (-14.6 U/L, P=0.028) and ALT (-15.4 U/L, P=0.023) by SN13T, regardless of live or dead. The fecal microflora analysis showed an increase of Firmicutes and the decreases of Bacteroidetes and Fusobacteria in both groups. Bifidobacterium was increased only in the live SN13T group. In conclusion, Lactobacillus plantarum SN13T alters the composition of gut microbiota and improves liver function in subjects with mild liver dysfunction. This clinical trial was registered with University hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) as UMIN000027440.

Antidepressant effects of moxidectin, an antiparasitic drug, in a rat model of depression

Substantial data indicate that an imbalance in gut microbiome (GM), also referred to as dysbiosis, may play an important role in depression. Moreover, drugs that normalize GM can result in an antidepressant-like effect. It was reported recently that moxidectin (MOX), an antiparasitic drug commonly used in veterinary medicine, has a positive influence on microbiota implicated in mood regulation. We undertook this study to determine whether MOX would actually show antidepressant-like properties in an animal model of depression and whether it would affect the hippocampal and frontal cortex levels of brain-derived neurotrophic factor (BDNF) or tumor necrosis factor (TNF)-alpha, peptides that have been implicated in pathogenesis of depression and effectiveness of various antidepressants. Adult male Wistar-Kyoto rats, a putative animal model of depression, were treated with a single dose of MOX (2.5 mg/kg, i.p.) and their performance in the open field locomotor activity (OFLA) as well as in the forced swim test (FST) was evaluated at 24 h, one week and two weeks after the single injection. A separate group of rats were injected with 2.5 mg/kg MOX and sacrificed 24 h later for neurochemical evaluations. MOX resulted in a decrease in immobility score after 24 h, whereas OFLA was not affected. Concomitant with the 24 h behavioral effects, the levels of hippocampal and frontal cortical BDNF were significantly increased, whereas the levels of TNF-alpha in both these areas were significantly decreased. The decrease in immobility scores was still evident after one week, but not 2 weeks of rest. These results indicate long lasting antidepressant effects of a single MOX dose and suggest potential utility of this drug in treatment-resistant depression.

SUN-LB020 The Role of Estradiol and Diet on the Gut Microbiome

Extensive research has shown that diet-induced obesity induces a bidirectional relationship between the gut microbiome and physiological health. However, the majority of this research was conducted using only male subjects. This is particularly problematic because sex hormones strongly influence the gut microbiome. Women have a different composition of gut bacteria than men. Additionally, imbalances in the gut microbiome have also been linked to diseases that are both predominately found in women, such as: PCOS and endometriosis. Interestingly, these reproductive conditions are comorbid with obesity. Therefore, the objective of this study was to examine the impact of diet-induced obesity on the female gut microbiome before and after ovariectomy and hormone replacement. To induce obesity, female Sprague-Dawley rats were fed a HFHS (high fat, high sugar) diet for 10 weeks. After this initial diet exposure, pre-operative fecal samples were collected and fasting blood glucose and insulin levels were determined. Following these procedures, all animals underwent bilateral ovariectomies. Half of each diet group was given a constant release 17β-Estradiol pellet (OVX+E), while the other half were not (OVX). Ovaries were fixed in paraformaldehyde and prepared for histology. A second fecal sample was collected two weeks post operation. At termination, blood samples were collected and fat pads were removed and weighed. Fecal DNA was extracted and then analyzed using qPCR. Primers for the major bacterial phyla were utilized. We focused primarily on Firmicutes and Bacteriodetes because the ratio of these phyla (Firmicutes: Bacteriodetes) is an established measure of gut health. If the ratio shifts towards Firmicutes, it is thought that the organism displays a greater level of gut dysbiosis. After 10 weeks on the diet, the HFHS rats weighed significantly more than the control animals. HFHS rats also displayed higher fasting blood glucose levels, higher fasting insulin levels, and insulin resistance. Similarly, the HFHS rats showed significantly larger Firmicutes: Bacteriodetes ratios indicating gut microbiome imbalance. After removal of the ovaries and estradiol replacement, OVX+E rats, regardless of diet, lost weight compared their OVX counterparts. This estradiol-driven weight loss was also associated with healthier gut microbiome profiles in the OVX+E rats. Interestingly, HFHS animals had a greater number of irregular estrus cycles and showed elevated numbers of ovarian cysts compared to control-fed females. This study provides a novel insight into the complex relationship between sex hormones, obesity, and the gut microbiome. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. s presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

NEW APPROACH TO ASSESSMENT AND CORRECTION OF INTESTINAL MICROBIOME IMBALANCE IN CHILDREN WITH ATOPIC DERMATITIS

Objectives - to study intestinal microbiota species for differentiated approach to treatment of atopic dermatitis (AD) in children. Material and methods. The study included 60 children, 34 girls and 26 boys aged from 3 to 12 years, with AD and concurrent intestinal dysbiosis. The experimental group consisted of 30 children assigned to differentiated correction of intestinal microbiome imbalance in addition to the standard therapy. Correction mode depended on the results of microbiological fecal examination of microbiota species using the mass spectrometry. The control group of 30 children received the standard treatment of atopic dermatitis. Results. Gut microbiome imbalance of different severity was revealed in all children with AD. The study ascertained the increase of the enterobacteria of various types, including true pathogenic ones, in atopic dermatitis. The direct correlation was revealed between the AD severity and the degree of dysbiosis with the coefficient value 0.69. As a result of complex treatment in the experimental group, the ratio of children with severe dysbiosis reduced from 60.0% to 20.0%, the proportion of children with moderate dysbiosis also decreased from 26.6% to 20.0%. The reduced treatment time was one of the study outcomes: 14 days in the experimental group and 21 days in the standard therapy group. Clinical remission was observed in 26.7% of children. Conclusion. The study supported the rationale for the differentiated approach to the treatment of AD in children. The preliminary microbiological study of feces for microbiota species by MALDI-ToF mass spectrometry is necessary. Selection of probiotics depends on the deficit or overbalance of the specific types of microorganisms in a patient. Thus the treatment effectiveness is improved and the remission period is extended.

The human-microbiome superorganism and its modulation to restore health

Microbiome is the community of microorganism that co-live with a host. The human being is the result of the integration of its genome and the coexistence with millions of microorganisms throughout its evolutionary history. Human-microbiome association can be considered a step of integration in evolution, constituting a superorganism. Many emergent diseases are related to the loss of part of this microbiome and its restoration can be achieved by different strategies. Gut microbiome imbalance is particularly associated with numerous inflammatory, immune and nervous system-related diseases by a communication pathway called microbiome–brain axis. Modulation of microbiome by administering prebiotics, like arabinoxylans, and synbiotics is a plausible treatment for dysbiosis, the regulation of neurotransmitters and alleviation of neurological manifestations.

D-methionine alleviates cisplatin-induced mucositis by restoring the gut microbiota structure and improving intestinal inflammation.

Background:There are close links between chemotherapy-induced intestinal mucositis and microbiota dysbiosis. Previous studies indicated that D-methionine was an excellent candidate for a chemopreventive agent. Here, we investigated the effects of D-methionine on cisplatin-induced mucositis.Materials and methods:Male Wistar rats (176–200 g, 6 weeks old) were given cisplatin (5 mg/kg) and treated with D-methionine (300 mg/kg). Histopathological, digestive enzymes activity, oxidative/antioxidant status, proinflammatory/anti-inflammatory cytokines in intestinal tissues were measured. Next-generation sequencing technologies were also performed to investigate the gut microbial ecology.Results:D-methionine administration increased villus length and crypt depth and improved digestive enzyme (leucine aminopeptidase, sucrose and alkaline phosphatase) activities in the brush-border membrane of cisplatin-treated rats (p < 0.05). Furthermore, D-methionine significantly attenuated oxidative stress and inflammatory reaction and increased interleukin-10 levels in cisplatin-induced intestinal mucositis (p < 0.05). Cisplatin administration resulted in high relative abundances of Deferribacteres and Proteobacteria and a low diversity of the microbiota when compared with control groups, D-methionine only and cisplatin plus D-methionine. Cisplatin markedly increased comparative abundances of Bacteroides caccae, Escherichia coli, Mucispirillum schaedleri, Bacteroides uniformis and Desulfovibrio C21-c20, while Lactobacillus was almost completely depleted, compared with the control group. There were higher abundances of Lactobacillus, Lachnospiraceae, and Clostridium butyrium in cisplatin plus D-methionine rats than in cisplatin rats. D-methionine treatment alone significantly increased the number of Lactobacillus reuteri.Conclusion:D-methionine protects against cisplatin-induced intestinal damage through antioxidative and anti-inflammatory effects. By enhancing growth of beneficial bacteria (Lachnospiraceae and Lactobacillus), D-methionine attenuates gut microbiome imbalance caused by cisplatin and maintains gut homeostasis.

Imbalance of gut microbiome and intestinal epithelial barrier dysfunction in cardiovascular disease.

The main function of the intestinal barrier is to regulate the absorption of nutrients, electrolytes, and water from the lumen into circulation and to prevent the entry of pathogenic microorganisms and toxic luminal substances. To maintain this function, an ideal microbiota balance is required and gut microbiota are critical for the intestinal epithelial barrier dysfunction and for the maintenance of physiological homeostasis. There is a demonstrable link between dysbiosis and intestinal dysfunction and diseases such as diabetes, obesity, and cardiovascular disease. However, links amongst gut pathology, microbial ecology, and blood pressure remain elusive. In a recent issue of Clinical Science (vol. 132, issue 6, 701-718), Kim et al. demonstrate a crucial link between gut microbiota and bacterial metabolites such as butyrate, gut leakiness, and hypertension.

Imbalance of gut microbiome and intestinal epithelial barrier dysfunction in patients with high blood pressure.

Recent evidence indicates a link between gut pathology and microbiome with hypertension (HTN) in animal models. However, whether this association exists in humans is unknown. Thus, our objectives in the present study were to test the hypotheses that high blood pressure (BP) patients have distinct gut microbiomes and that gut-epithelial barrier function markers and microbiome composition could predict systolic BP (SBP). Fecal samples, analyzed by shotgun metagenomics, displayed taxonomic and functional changes, including altered butyrate production between patients with high BP and reference subjects. Significant increases in plasma of intestinal fatty acid binding protein (I-FABP), lipopolysaccharide (LPS), and augmented gut-targetting proinflammatory T helper 17 (Th17) cells in high BP patients demonstrated increased intestinal inflammation and permeability. Zonulin, a gut epithelial tight junction protein regulator, was markedly elevated, further supporting gut barrier dysfunction in high BP. Zonulin strongly correlated with SBP (R2 = 0.5301, P<0.0001). Two models predicting SBP were built using stepwise linear regression analysis of microbiome data and circulating markers of gut health, and validated in a separate cohort by prediction of SBP from zonulin in plasma (R2 = 0.4608, P<0.0001). The mouse model of HTN, chronic angiotensin II (Ang II) infusion, was used to confirm the effects of butyrate and gut barrier function on the cardiovascular system and BP. These results support our conclusion that intestinal barrier dysfunction and microbiome function are linked to HTN in humans. They suggest that manipulation of gut microbiome and its barrier functions could be the new therapeutic and diagnostic avenues for HTN.

Gut Microbiome Imbalance: Pathways to Weight Gain and Illness

Gut Microbiome Imbalance: Pathways to Weight Gain and Illness