Gender differences, aging and hormonal status in mucosal injury and repair

Deciphering the influence of gut and oral microbiomes on menopause for healthy aging

Menopause is characterized by the cessation of menstruation and a decline in reproductive function, which is an intrinsic component of the aging process. However, it has been a frequently overlooked field of women's health. The oral and gut microbiota, constituting the largest ecosystem within the human body, are important for maintaining human health and notably contribute to the healthy aging of menopausal women. Therefore, a comprehensive review elucidating the impact of the gut and oral microbiota on menopause for healthy aging is of paramount importance. This paper presents the current understanding of the microbiome during menopause, with a particular focus on alterations in the oral and gut microbiota. Our study elucidates the complex interplay between the microbiome and sex hormone levels, explores microbial crosstalk dynamics, and investigates the associations between the microbiome and diseases linked to menopause. Additionally, this review explores the potential of microbiome-targeting therapies for managing menopause-related diseases. Given that menopause can last for approximately 30 years, gaining insights into how the microbiome and menopause interact could pave the way for innovative interventions, which may result in symptomatic relief from menopause and an increase in quality of life in women.

Estrogen Alleviates Oxidative Bowel Injury and Neuroinflammation in Necrotizing Enterocolitis

INTRODUCTION

High mortality and morbidity of neonates with necrotizing enterocolitis (NEC) necessitates the investigation of novel therapies to improve outcomes. It was aimed to elucidate the potential therapeutic effect of estrogen receptor agonists on NEC-induced intestinal and brain injury in rats.

METHODS

Sprague-Dawley pups of both sexes were separated from their mothers at postnatal 5th d. Feeding with formula along with a single session of hypoxia was applied to induce NEC, while control pups were kept with their mothers. The NEC rats received either vehicle, estrogen receptor α (ERα) agonist propyl pyrazole triol (1 mg/kg/day), ERβ agonist diarylpropionitrile (1 mg/kg/day), or 17β-estradiol (1 mg/kg/day) during maternal separation. All pups were decapitated on postnatal 9th d to collect intestinal and brain tissue samples.

RESULTS

Elevation in proinflammatory cytokines, apoptosis, and microscopically and biochemically evident oxidative injury in both the intestinal and brain tissues were observed in NEC-induced pups. In both the intestinal and brain tissues, nerve growth factor and brain-derived neurotrophic factor protein levels were depleted, expressions of both the ESR1 and ESR2 genes were downregulated, while treatment with 17β-estradiol or ER agonists alleviated extent of oxidative injury of the intestines and brain tissue, upregulated nerve growth factor, brain-derived neurotrophic factor, and ER gene expressions, abolished NEC-induced decrease in claudin-3 expression, increased the survival rates, improved the clinical states of the survived pups at varying degrees.

CONCLUSIONS

Activation of estrogen signaling by receptor agonists alleviated NEC-induced intestinal and cerebral injury, implicating that estrogen agonists could be regarded as promising preventive/therapeutic agents for NEC.

Novel Functional Dressing Materials for Intraoral Wound Care

Intraoral wounds represent a particularly challenging category of mucosal and hard tissue injuries, characterized by the unique structures, complex environment, and distinctive healing processes within the oral cavity. They have a common occurrence yet frequently inflict significant inconvenience and pain on patients, causing a serious decline in the quality of life. A variety of novel functional dressings specifically designed for the moist and dynamic oral environment have been developed and realized accelerated and improved wound healing. Thoroughly analyzing and summarizing these materials is of paramount importance in enhancing the understanding and proficiently managing intraoral wounds. In this review, the particular processes and unique characteristics of intraoral wound healing are firstly described. Up-to-date knowledge of various forms, properties, and applications of existing products are then intensively discussed, which are categorized into animal products, plant extracts, natural polymers, and synthetic products. To conclude, this review presents a comprehensive framework of currently available functional intraoral wound dressings, with an aim to provoke inspiration of future studies to design more convenient and versatile materials.

The Role of Estrogen across Multiple Disease Mechanisms

Estrogen is a significant hormone that is involved in a multitude of physiological and pathological processes. In addition to its pivotal role in the reproductive system, estrogen is also implicated in the pathogenesis of a multitude of diseases. Nevertheless, previous research on the role of estrogen in a multitude of diseases, including Alzheimer's disease, depression, cardiovascular disease, diabetes, osteoporosis, gastrointestinal diseases, and estrogen-dependent cancers, has concentrated on a single disease area, resulting in a lack of comprehensive understanding of cross-disease mechanisms. This has brought some challenges to the current treatment methods for these diseases, because estrogen as a potential therapeutic tool has not yet fully developed its potential. Therefore, this review aims to comprehensively explore the mechanism of estrogen in these seven types of diseases. The objective of this study is to describe the relationship between each disease and estrogen, including the ways in which estrogen participates in regulating disease mechanisms, and to outline the efficacy of estrogen in treating these diseases in clinical practice. By studying the role of estrogen in a variety of disease mechanisms, it is hoped that a more accurate theoretical basis and clinical guidance for future treatment strategies will be provided, thus promoting the effective management and treatment of these diseases.

Sex difference in the associations among risk factors with gastroesophageal reflux disease in a large Taiwanese population study

BACKGROUND

Gastroesophageal reflux disease (GERD) is a common global health issue. Previous studies have revealed a higher prevalence of GERD in females than in males, however few studies have investigated sex differences in the risk factors associated with GERD. Therefore, the aim of this population-based study was to examine sex differences in the risk factors for GERD in a large cohort of over 120,000 Taiwanese participants.

METHODS

We enrolled 121,583 participants (male: 43,698; female: 77,885; mean age 49.9 ± 11.0 years) from the Taiwan Biobank. The presence of GERD was ascertained using self-reported questionnaires. Sex differences in the risk factors associated with GERD were examined using multivariable logistic regression analysis.

RESULTS

The overall prevalence of GERD was 13.7%, including 13.0% in the male participants and 14.1% in the female participants (p < 0.001). Multivariable analysis showed that older age, hypertension, smoking history, alcohol history, low fasting glucose, and low uric acid were significantly associated with GERD in the male participants. In the female participants, older age, diabetes, hypertension, smoking history, alcohol history, low systolic blood pressure, low fasting glucose, high hemoglobin, high total cholesterol, low high-density lipoprotein cholesterol (HDL-C), low low-density lipoprotein cholesterol, and low uric acid were significantly associated with GERD. Significant interactions were found between sex and age (p < 0.001), diabetes (p < 0.001), smoking history (p < 0.001), fasting glucose (p = 0.002), triglycerides (p = 0.001), HDL-C (p = 0.001), and estimated glomerular filtration rate (p = 0.002) on GERD.

CONCLUSIONS

Our results showed a higher prevalence of GERD among females compared to males. Furthermore, sex differences were identified in the risk factors associated with GERD, and older age, diabetes, smoking history, and low HDL-C were more closely related to GERD in females than in males.

Main Disorders of Gastrointestinal Tract in Older People: An Overview

From a physiological standpoint, aging is a progressive reduction in each organ system’s capacity to maintain homeostasis in the face of illness or stressors. With advancing age, gastrointestinal (GI) symptoms and signs may increase, not only due to the aging processes but also to the superimposed effects of comorbidities, which can badly affect digestive functions (i.e., diabetes, malignancy, etc.) and environmental exposure. In general, gastrointestinal symptoms in older people more often underlie organic pathologies, while GI functional disorders are less frequently diagnosed in this age group. Moreover, gastrointestinal disease can also present in a nuanced and atypical manner, making the diagnostic hypothesis and, consequently, the correct diagnosis and therapy more challenging. In addition, with reference to this age group, the clinical implications of gastrointestinal pathologies can be more severe due to a decreased physiologic reserve, with a higher risk for malnutrition resulting in falls, depression, social isolation, and a deterioration of functional status. In this review, we focused on the most frequent GI tract disorders, highlighting the main age-related changes, their epidemiological, pathophysiological and clinical implications, and any differences with younger patients.

The prevalence of myocardial infarction in the elderly: A systematic review and meta-analysis

BACKGROUND

Myocardial Infarction (MI) refers to the destruction and death of cells in the myocardium of the heart. Its prevalence increases with age due to changes in the cardiovascular system. The aim of the present study was to combine, summarize, standardize, resolve inconsistencies in the results of studies, and investigate the impact of potential factors on the prevalence rate of MI in the elderly through a systematic review and meta-analysis.

METHODS

This systematic review and meta-analysis was conducted from 1987 to March 2022. All relevant published studies were searched in PubMed, Embase, Scopus, Web of Science (WoS) databases, and Google Scholar search engine using related MeSH/Emtree and Free Text words. The heterogeneity among studies was quantified using the I2 index.

RESULTS

In the initial search, 35453 studies were identified. After eliminating irrelevant studies, finally, 29 articles with a sample size of 3279136 subjects were included in the meta-analysis. After combining the results of the studies included in the meta-analysis, the total prevalence of MI in the elderly was estimated to be 17.6% (95% CI: 12.8 - 23.7%), 16.1% (95% CI: 11.0 - 22.8%) in males, and 12.5% (95% CI: 9.2 - 16.8%) in females. The prevalence of MI increased with the year of publication and the mean age of the elderly (P < 0.001).

CONCLUSION

The results showed that due to the high prevalence of myocardial infarction (MI) in the elderly, it should be addressed within healthcare systems and policy makers should pay more attention to prevention of MI. However, considering the inclusion of heterogeneous studies, the pooled estimation should be interpreted with caution.

Predictive Factors for the Outcome of Unsupervised Endoscopic Submucosal Dissection During the Initial Learning Curve with Prevalence-Based Indication

BACKGROUND

For an adequate educational strategy of ESD in non-Asian settings with prevalence-based indication it is essential to define adequate lesions, suitable for the beginner without on-site expert-supervision.

AIMS

We analyzed possible predictors for outcome parameters of effectiveness and safety during the initial learning curve.

METHODS

The first 120 ESDs of four operators (n = 480), performed between 2007 and 2020 in four tertiary hospitals, were enrolled. Uni-/multivariable regression analysis was done with sex, age, pretreated lesion, lesion size, organ, and organ-based localization as possible independent predictors for en bloc resection (EBR), complication, and resection speed.

RESULTS

Rates of EBR, complication, and resection speed were 84.5%, 14.2%, and 6.20 (± 4.45) cm2/h. Independent predictors for EBR were pretreated lesion (OR 0.27 [0.13-0.57], p < 0.001) and non-colonic ESD (OR 2.29 [1.26-4.17] (rectum)/5.72 [2.36-13.89] (stomach)/7.80 [2.60-23.42] (esophagus), p < 0.001), for complication pretreated lesion (OR 3.04 [1.46-6.34], p < 0.001) and lesion size (OR 1.02 [1.004-1.04], p = 0.012) and for resection speed pretreated lesion (RC - 3.10 [- 4.39 to - 1.81], p < 0.001), lesion size (RC 0.13 [0.11-0.16], p < 0.001) and male patient (RC - 1.11 [- 1.85 to - 0.37], p < 0.001). We found no significant difference in the incidence of technically unsuccessful resections in esophageal (1/84), gastric (3/113), rectal (7/181), and colonic (3/101) ESDs (p = 0.76). Technical failure was mainly caused by complication and fibrosis/pretreatment.

CONCLUSION

During the initial learning curve of an unsupervised ESD program with prevalence-based indication, pretreated lesions and colonic ESDs should be avoided. In contrast, lesion size and organ-based localizations have less predictive value for the outcome.

Intestinal epithelial stem cell transplants as a novel therapy for cerebrovascular stroke

Almost 2/3rds of stroke survivors exhibit vascular cognitive impairment and a third of stroke patients will develop dementia 1-3 years after stroke. These dire consequences underscore the need for effective stroke therapies. In addition to its damaging effects on the brain, stroke rapidly dysregulates the intestinal epithelium, resulting in elevated blood levels of inflammatory cytokines and toxic gut metabolites due to a 'leaky' gut. We tested whether repairing the gut via intestinal epithelial stem cell (IESC) transplants would also improve stroke recovery. Organoids containing IESCs derived from young rats transplanted into older rats after stroke were incorporated into the gut, restored stroke-induced gut dysmorphology and decreased gut permeability, and reduced circulating levels of endotoxin LPS and the inflammatory cytokine IL-17A. Remarkably, IESC transplants also improved stroke-induced acute (4d) sensory-motor disability and chronic (30d) cognitive-affective function. Moreover, IESCs from older animals displayed senescent features and were not therapeutic for stroke. These data underscore the gut as a critical therapeutic target for stroke and demonstrate the effectiveness of gut stem cell therapy.

Organotypic cultures as aging associated disease models

Aging remains a primary risk factor for a host of diseases, including leading causes of death. Aging and associated diseases are inherently multifactorial, with numerous contributing factors and phenotypes at the molecular, cellular, tissue, and organismal scales. Despite the complexity of aging phenomena, models currently used in aging research possess limitations. Frequently used in vivo models often have important physiological differences, age at different rates, or are genetically engineered to match late disease phenotypes rather than early causes. Conversely, routinely used in vitro models lack the complex tissue-scale and systemic cues that are disrupted in aging. To fill in gaps between in vivo and traditional in vitro models, researchers have increasingly been turning to organotypic models, which provide increased physiological relevance with the accessibility and control of in vitro context. While powerful tools, the development of these models is a field of its own, and many aging researchers may be unaware of recent progress in organotypic models, or hesitant to include these models in their own work. In this review, we describe recent progress in tissue engineering applied to organotypic models, highlighting examples explicitly linked to aging and associated disease, as well as examples of models that are relevant to aging. We specifically highlight progress made in skin, gut, and skeletal muscle, and describe how recently demonstrated models have been used for aging studies or similar phenotypes. Throughout, this review emphasizes the accessibility of these models and aims to provide a resource for researchers seeking to leverage these powerful tools.

Impact of Age and Sex on Electrical Impedance Values in Healthy Oral Mucosa

Background: Electrical impedance (EI) is a property of all living tissues and represents the resistance to the electric current flow through a living tissue. EI depends on the structure and chemical composition of the tissue. The aim of this study was to determine the influence of age, sex, and electrode pressure on the EI values of healthy oral mucosa. The study involved 101 participants with healthy oral mucosa who were divided into three age groups. EI was measured in seven anatomical regions. Results: Significant differences between different age groups were found. Younger participants (20–40 years) had significantly higher EI values than the older participants (60+). Significantly higher EI values were found in women at all localisations at all measured frequencies, except on the hard palate. EI values measured with higher sub-pressure were significantly lower than values measured with lower sub-pressure at all frequencies and localisations, except the tongue dorsum, tongue border, and sublingual mucosa. Conclusions: This study found that EI values in healthy oral mucosa depend on age and sex and may also depend on the pressure of the measuring device. These factors should be kept in mind when EI is used as a diagnostic method for different oral lesions.

Potential utility of a non-invasive menstrual blood immunophenotype analysis in reproductive medicine

Purpose Can a comprehensive flow cytometry panel be used to assess immunophenotype profiles in menstrual blood of patients experiencing reproductive failure and age matched controls of proven fertility? Methods 58 recurrent pregnancy loss and repeated implantation failure patients, along with 15 age matched controls of proven fertility, had menstrual blood samples obtained within the first 24 hours of the onset of menstruation to non-invasively assess the local immunophenotype. Using a comprehensive multi-parameter flow panel the lymphocyte sub-populations were described and compared. Results Relative to well established peripheral blood immunophenotyping values, distinct lymphocyte population differences were noted between the subgroups. The ratios of CD4+ and CD8+ T-cells were inverted relative to peripheral blood and uterine NK cells represented by CD56bright were distinctly visualised, emphasising the distinction of menstrual and peripheral blood. Relative to controls there were marked increases in CD3+ve T-cells (p=0.009), CD4:CD8 ratio (p=0.004), CD19 B-cells (p=0.026) and CD56dim NK's (p=0.002) in the reproductive failure cases. Conclusions Flow cytometric evaluation can provide a rapid and objective analysis of lymphocyte subpopulations in many forms of tissue and fluid. The findings show significant variations in cellular composition of immune cells indicating a distinct compartment, with differences between cases and controls. Immunological assessment of the menstrual blood immunophenotype, in clinically appropriate patients, may provide insight into the aetiology of adverse reproductive outcome, without the risks and inconveniences associated with a more invasive endometrial biopsy.

Spotlight on the Gut Microbiome in Menopause: Current Insights

The gut microbiome is an important contributor to human health, shaped by many endogenous and exogenous factors. The gut microbiome displays sexual dimorphism, suggesting influence of sex hormones, and also has been shown to change with aging. Yet, little is known regarding the influence of menopause - a pivotal event of reproductive aging in women - on the gut microbiome. Here, we summarize what is known regarding the interrelationships of female sex hormones and the gut microbiome, and review the available literature on menopause, female sex hormones, and the gut microbiome in humans. Taken together, research suggests that menopause is associated with lower gut microbiome diversity and a shift toward greater similarity to the male gut microbiome, however more research is needed in large study populations to identify replicable patterns in taxa impacted by menopause. Many gaps in knowledge remain, including the role the gut microbiome may play in menopause-related disease risks, and whether menopausal hormone therapy modifies menopause-related change in the gut microbiome. Given the modifiable nature of the gut microbiome, better understanding of its role in menopause-related health will be critical to identify novel opportunities for improvement of peri- and post-menopausal health and well-being.

From Static to Dynamic: A Review on the Role of Mucus Heterogeneity in Particle and Microbial Transport

Mucus layers (McLs) are on the front line of the human defense system that protect us from foreign abiotic/biotic particles (e.g., airborne virus SARS-CoV-2) and lubricates our organs. Recently, the impact of McLs on human health (e.g., nutrient absorption and drug delivery) and diseases (e.g., infections and cancers) has been studied extensively, yet their mechanisms are still not fully understood due to their high variety among organs and individuals. We characterize these variances as the heterogeneity of McLs, which lies in the thickness, composition, and physiology, making the systematic research on the roles of McLs in human health and diseases very challenging. To advance mucosal organoids and develop effective drug delivery systems, a comprehensive understanding of McLs' heterogeneity and how it impacts mucus physiology is urgently needed. When the role of airway mucus in the penetration and transmission of coronavirus (CoV) is considered, this understanding may also enable a better explanation and prediction of the CoV's behavior. Hence, in this Review, we summarize the variances of McLs among organs, health conditions, and experimental settings as well as recent advances in experimental measurements, data analysis, and model development for simulations.

Bladder Microbiota Are Associated with Clinical Conditions That Extend beyond the Urinary Tract

Background. Since the discovery of the human urinary microbiota (UM), alterations in microbial community composition have been associated with various genitourinary conditions. The aim of this exploratory study was to examine possible associations of UM with clinical conditions beyond the urinary tract and to test some of the conclusions from previous studies on UM. Methods. Catheterised urine samples from 87 men were collected prior to endoscopic urological interventions under anaesthesia. The composition of the bacterial community in urine was characterized using the hypervariable V4 region of the 16S rRNA gene. Samples from 58 patients yielded a sufficient amount of bacterial DNA for analysis. Alpha diversity measures (number of operational taxonomic units, ACE, iChao2, Shannon and Simpson indices) were compared with the Kruskal–Wallis test. Beta diversity (differences in microbial community composition) was assessed using non-metric dimensional scaling in combination with the Prevalence in Microbiome Analysis algorithm. Results. Differences in bacterial richness and diversity were observed for the following variables: age, diabetes mellitus, dyslipidemia, smoking status and single-dose preoperative antibiotics. Differences in microbial community composition were observed in the presence of chronic kidney disease, lower urinary tract symptoms and antibiotic prophylaxis. Conclusions. UM appears to be associated with certain clinical conditions, including those unrelated to the urinary tract. Further investigation is needed before conclusions can be drawn for diagnostics and treatment.

Multisite prospective Liver Disease and Reproductive Ageing (LIVRA) study in US women living with and without HIV

PURPOSE

The Liver Disease and Reproductive Ageing (LIVRA) study leverages the infrastructure of the decades-long multicentre prospective Women's Interagency HIV Study (WIHS) to examine the contributions of HIV, hepatitis C virus (HCV) and ageing to liver disease progression in women.

PARTICIPANTS

From 2013 to 2018, LIVRA enrolled 1576 participants (77 HCV-seropositive only, 248 HIV/HCV-seropositive, 868 HIV-seropositive only and 383 HIV/HCV-seronegative) who underwent vibration controlled transient elastography (VCTE). A VCTE quality assurance programme was established to ensure consistency and accuracy for longitudinal assessment of steatosis (fatty liver) via the controlled attenuation parameter (CAP) and fibrosis via liver stiffness (LS). Demographic, lifestyle factors, anthropometry, clinical and medication history, host genetics, immune markers and hormone levels were collected as part of the WIHS.

FINDINGS TO DATE

At baseline, 737 of 1543 women with CAP measurements had steatosis (CAP ≥248 dB/m) and 375 of 1576 women with LS measurements had significant fibrosis (LS ≥7.1 kPa), yielding a prevalence of 48% and 24%, respectively. On multivariable analysis, waist circumference (WC) and insulin resistance were independently associated with higher CAP (17.8 dB/m per 10 cm (95% CI:16.2 to 19.5) and 1.2 dB/m per doubling (95% CI:0.8 to 1.6), respectively). By contrast, HIV/HCV seropositivity and HCV seropositivity alone were associated with less steatosis compared with HIV/HCV-seronegative women, although the latter did not reach statistical significance (-9.2 dB/m (95% CI:-18.2 to -0.3) and -10.4 dB/m (95% CI: -23.8 to 3.1), respectively). Factors independently associated with higher LS were age (4.4% per 10 years (95% CI: 0.4% to 8.4%)), WC (5.0% per 10 cm (95% CI: 3.3% to 6.6%)), CAP steatosis (0.6% per 10 dB/m (95% CI: 0.1% to 1.0%)), HIV/HCV seropositivity (33% (95% CI: 24% to 44%)) and HCV seropositivity alone (43% (95% CI: 28% to 60%)). Excluding scans that were invalid based on traditional criteria for unreliability did not affect the results.

FUTURE PLANS

Enrolled women undergo VCTE at 3-year intervals unless LS is ≥9.5 kPa, indicating advanced fibrosis, in which case VCTE is performed annually. Participants also undergo VCTE every 6 months until 18 months after HCV treatment initiation. Analysis of the data collected will provide insights into the impact of ageing/ovarian function, host genetics, immune function and contemporary HIV and HCV treatments on liver disease progression.

The Reproductive Transition: Effects on Viral Replication, Immune Activation, and Metabolism in Women with HIV infection

PURPOSE OF REVIEW

To describe research advances in the menopausal transition (MT) and its effects on HIV replication, immune activation, and metabolic parameters in women living with HIV (WLWH).

RECENT FINDINGS

Physiologic changes due to declines in ovarian reserve characterize the MT. Evidence suggests that estrogen depletion influences HIV replication and the latent reservoir. Changes in markers of immune activation, waist circumference, and neurocognition, independent of chronologic age, occur before the final menstrual period (FMP). HIV effects on gut microbial translocation and adipose tissue, as well as health disparities in WLWH may contribute. Improved biomarker sensitivity to predict FMP provides opportunities to study MT in WLWH. Research is needed to determine the effects of MT and HIV on virologic and clinical outcomes, using accurate assessments to predict the FMP and menopausal stages. These findings could inform the timing of interventions to prevent early onset of adverse outcomes in WLWH.

Menopause Is Associated With Immune Activation in Women With HIV

BACKGROUND

Persistent immune activation due to gut barrier dysfunction is a suspected cause of morbidity in HIV, but the impact of menopause on this pathway is unknown.

METHODS

In 350 women with HIV from the Women's Interagency HIV Study, plasma biomarkers of gut barrier dysfunction (intestinal fatty acid binding protein; IFAB), innate immune activation (soluble CD14 and CD163; sCD14, sCD163), and systemic inflammation (interleukin-6 and tumor necrosis factor receptor 1; IL-6, TNFR1) were measured at 674 person-visits spanning ≤2 years.

RESULTS

Menopause (post- vs premenopausal status) was associated with higher plasma sCD14 and sCD163 in linear mixed-effects regression adjusting for age and other covariates (β = 161.89 ng/mL; 95% confidence interval [CI], 18.37-305.41 and 65.48 ng/mL, 95% CI, 6.64-124.33, respectively); but not with plasma IFAB, IL-6, or TNFR1. In piece-wise linear mixed-effects regression of biomarkers on years before/after the final menstrual period, sCD14 increased during the menopausal transition by 250.71 ng/mL per year (95% CI, 16.63-484.79; P = .04), but not in premenopausal or postmenopausal periods.

CONCLUSIONS

In women with HIV, menopause may increase innate immune activation, but data did not support an influence on the gut barrier or inflammation. Clinical implications of immune activation during menopausal transition warrant further investigation.

Nutrition and Healthy Aging: Prevention and Treatment of Gastrointestinal Diseases

Nutritional well-being is a fundamental aspect for the health, autonomy and, therefore, the quality of life of all people, but especially of the elderly. It is estimated that at least half of non-institutionalized elderly people need nutritional intervention to improve their health and that 85% have one or more chronic diseases that could improve with correct nutrition. Although prevalence estimates are highly variable, depending on the population considered and the tool used for its assessment, malnutrition in the elderly has been reported up to 50%. Older patients are particularly at risk of malnutrition, due to multiple etiopathogenetic factors which can lead to a reduction or utilization in the intake of nutrients, a progressive loss of functional autonomy with dependence on food, and psychological problems related to economic or social isolation, e.g., linked to poverty or loneliness. Changes in the aging gut involve the mechanical disintegration of food, gastrointestinal motor function, food transit, intestinal wall function, and chemical digestion of food. These alterations progressively lead to the reduced ability to supply the body with adequate levels of nutrients, with the consequent development of malnutrition. Furthermore, studies have shown that the quality of life is impaired both in gastrointestinal diseases, but especially in malnutrition. A better understanding of the pathophysiology of malnutrition in elderly people is necessary to promote the knowledge of age-related changes in appetite, food intake, homeostasis, and body composition in order to better develop effective prevention and intervention strategies to achieve healthy aging.

Helicobacter pylori Infection in Geriatric Patients: Current Situation and Treatment Regimens

Helicobacter pylori (H. pylori) has so far infected more than half the global population. It is the most important and controllable risk factor for gastric cancer. The elderly, who are at a higher incidence of the infection, are also commonly found to develop antibiotic resistance. The symptoms, diagnosis, clinical features (of gastric or extra-digestive diseases), and treatment of H. pylori infection in the elderly, are different from that in the non-elderly. Health conditions, including comorbidities and combined medication have limited the use of regular therapies in elderly patients. However, they can still benefit from eradication therapy, thus preventing gastric mucosal lesions and gastric cancer. In addition, new approaches, such as dual therapy and complementary therapy, have the potential to treat older patients with H. pylori infection.

The Phenotypic Difference of IgA Nephropathy and its Race/Gender-dependent Molecular Mechanisms

IgA nephropathy (IgAn), defined by the pre dominant de position of IgA in the glomerular mesangium, is the most common form of GN throughout the world. However, its incidence, sex distribution, clinical presentation, and progression and pathogenic initiating factors are largely variable and do not fit such a simple definition. To assess the heterogeneity of this disease, we recently conducted a clinical survey on the presentation and clinical management of patients with IgAn in Europe and Japan. This clinical survey highlights similarities and differences in patients from different cont inents. The survey revealed obvious differences between nations in the frequency of gastrointestinal complications, including inflammatory bowel diseases (IBD) and celiac disease, which were more frequent in European patients. Such findings are compatible with susceptibility loci related to intestinal immunity and IBD in recent genome wide association studies (GWAS) on IgAn. However, most of the molecules in these mucosal-related loci fulfill the immunologic function not only of gut-associated lymphoid tissue (GALT), but also nasopharyngeal/bronchial-associated lymphoid tissues (NALT/BALT). Indeed, a similar frequency of macrohematuria coinciding with upper respiratory infection, a hallmark manifestation of this disease, was found in the survey, emphasizing the pathogenic roles of these molecules in the NALT/BALT of patients with IgAn. Recent experimental and clinical studies including GWAS on multiple common infections and IBD indicate immune crosstalk between GALT and NALT/BALT, and some related mediators, such as TNF superfamily ligands (APRIL/BAFF). This review explains the epidemiologic heterogeneity of this disease with the clinical survey, and discusses race and sex-dependent molecular mechanisms.

Gender Difference in Chronic Cough: Are Women More Likely to Cough?

Chronic cough is a common complaint for patients to seek medical cares all over the world. Worldwide, about two thirds of chronic cough patients are females. However, in some regions of China the prevalence of chronic cough between sexes is roughly the same. Estrogen and progesterone can not only have an effect on transient receptor potential vanilloid 1 channel, eosinophils and mast cells, but also influence laryngeal dysfunction, gastroesophageal reflux disease and obstructive sleep apnea hypopnea syndrome, which may lead to increased cough sensitivity in women. On the other hand, the quality of life was adversely affected more in female patients with chronic cough. Both hormones possibly cause gender difference in chronic cough.

Is Estrogen a Curse or a Blessing in Disguise? Role of Estrogen in Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD), a condition wherein there is reflux of stomach contents into the esophagus, causing heartburn and regurgitation with a sour and bitter taste in the mouth. It may or may not lead to mucosal injury. GERD symptoms can be troublesome and negatively impact the quality of life. Estrogen, the sex hormone in females, may play a role in the gender differences observed in GERD symptoms. This review article analyzes estrogen's mechanism in the causation of GERD symptoms and its complications. A better understanding of pathophysiology will help us guide early detection, treatment, and prevention of repeated reflux complications. We did a comprehensive PubMed database search and analyzed differences in GERD symptoms experienced by males and females and the role of estrogen in erosive and non-erosive GERD. GERD symptoms in association with hormonal replacement therapy (HRT) and pregnancy, the lower esophageal sphincter (LES) relaxant effects, and estrogens' protective effect on the esophagus from mucosal injury due to repeated reflux are discussed. Estrogen can cause GERD as an adverse effect and, at the same time, can be used to protect the mucosa from GERD induced injury and its complications like metaplasia and cancer. The mechanism is complex and requires further studies and trials. We recommend future researchers to look for possible estrogen use to treat erosive GERD and complication prevention.

Implications of Sex Differences in Immunity for SARS-CoV-2 Pathogenesis and Design of Therapeutic Interventions

Men present more frequently with severe manifestations of coronavirus disease 2019 (COVID-19) and are at higher risk for death. The underlying mechanisms for these differences between female and male individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are insufficiently understood. However, studies from other viral infections have shown that females can mount stronger immune responses against viruses than males. Emerging knowledge on the basic biological pathways that underlie differences in immune responses between women and men needs to be incorporated into research efforts on SARS-CoV-2 pathogenesis and pathology to identify targets for therapeutic interventions aimed at enhancing antiviral immune function and lung airway resilience while reducing pathogenic inflammation in COVID-19.

The prognostic value of gender in gastric gastrointestinal stromal tumors: a propensity score matching analysis

Background

Gastrointestinal stromal tumors (GISTs) of the stomach are the most common GISTs. The risk, incidence, and outcome of cancer are different between the sexes. Whether gender is related to the prognosis of gastric stromal tumors is unclear. Therefore, this study aims to explore the relationship between gender and gastric GIST prognosis.

Methods

Data from gastric GIST patients were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was performed to reduce confounding factors, and the clinicopathological features and prognosis of GIST patients were comprehensively evaluated.

Results

There were 512 male patients and 538 female patients with gastric GIST. The gender of gastric GIST patients was associated with marital status, surgical treatment, tumor size, and mitotic index (P < 0.05). The Kaplan-Meier analysis and log-rank test revealed that male patients had a higher mortality rate than female patients (P = 0.0024). After matching all the potential confounding factors, the survival of the female gastric GIST patients was better than that of the male gastric GIST patients (P = 0.042). Cox regression analysis revealed that gender was an independent risk factor for overall survival. The risk of death was higher for males than for females (HR 1.677, 95% CI 1.150–2.444, P = 0.007).

Conclusion

Gender could be a prognostic factor for gastric GIST survival, and male patients had a higher risk of death.

Gastrointestinal discomforts and dietary intake in Chinese urban elders: A cross-sectional study in eight cities of China

BACKGROUND

Gastrointestinal (GI) discomforts are common in the elderly population; however, whether such discomforts are associated with dietary intake has not been studied.

AIM

To evaluate GI discomforts in Chinese urban elders and the associated factors.

METHODS

The gastrointestinal symptom rating scale (GSRS) was used to identify GI discomforts in 688 elders from eight cities of China. The semi-quantitative food frequency questionnaire and one time of 24 h dietary recall were used to access the food intake, identify dietary pattern, and calculate the nutrients intake.

RESULTS

About 83% of studied elders experienced at least one of GI discomforts in the past 6 mo; dyspepsia was the most commonly reported (66.7%), followed by reflux (44.8%), abdominal pain (35.9%), constipation (35.8%), and diarrhea (34.7%). Female gender, lower education level, and lower family income were associated with a higher GSRS score. Participants who were diagnosed with a GI-related disease had a higher score of constipation, but a lower score of reflux. Chronic diseases were positively associated with certain GI discomforts. Three dietary patterns were identified by the method of principal component analysis, which were characterized as high intake of salt and tea; more frequent intake of tubers, fruits, aquatic products, and soybeans; and high intake of cereal, vegetables, and meat, respectively. However, no associations between dietary patterns and GSRS score were found. The elders with a higher GSRS score had significantly lower intake of bean products. The elders whose GSRS score was ≥ 21 and 18-20 decreased their bean production intake by 7.2 (0.3, 14.3) g/d and 14.3 (1.2, 27.3) g/d, respectively, compared with those who had a GSRS score ≤ 17. There were no differences in other food categories, calories, or nutrients intake among elders with different GSRS scores.

CONCLUSION

GI discomforts are common in Chinese urban elders. GI discomforts might be associated with the choice of food.

Impact of chronic immobilization stress on parameters of colonic homeostasis in BALB/c mice

The intestinal epithelium is a monolayer of cells arranged side‑by‑side and connected by tight junction (TJ) proteins expressed at the apical extreme of the paracellular membrane. This layer prevents stress‑induced inflammatory responses, thus helping to maintain gut barrier function and gut homeostasis. The aim of the present study was to evaluate the effects of chronic immobilization stress on the colonic expression of various parameters of homeostasis. A total of two groups of female BALB/c mice (n=6) were included: A stressed group (short‑term immobilization for 2 h/day for 4 consecutive days) and an unstressed (control) group. Colon samples were obtained to detect neutrophils and goblet cells by optical microscopy, TJ protein expression (occludin, and claudin ‑2, ‑4, ‑7, ‑12 and ‑15) by western blotting, mRNA levels of TJ genes and proinflammatory cytokines [tumor necrosis factor (TNF)‑α, interleukin (IL)‑1β, ‑6 and ‑8] by reverse transcription‑quantitative PCR, fecal lactoferrin by ELISA and the number of colony‑forming units of aerobic bacteria. Compared with goblet cells in control mice, goblet cells were enlarged and reduced in number in stressed mice, whereas neutrophil cellularity was unaltered. Stressed mice exhibited reduced mRNA expression for all evaluated TJ mRNAs, with the exception of claudin‑7, which was upregulated. Protein levels of occludin and all claudins (with the exception of claudin‑12) were decreased in stressed mice. Fecal lactoferrin, proinflammatory cytokine mRNA levels and aerobic bacterial counts were all increased in the stressed group. These results indicated that immobilization stress induced proinflammatory and potential remodeling effects in the colon by decreasing TJ protein expression. The present study may be a useful reference for therapies aiming to regulate the effects of stress on intestinal inflammatory dysfunction.

17β-Estradiol protects the esophageal epithelium from IL-13-induced barrier dysfunction and remodeling

BACKGROUND

The incidence of eosinophilic esophagitis (EoE) is greater in male than female subjects, and the underlying molecular basis for this sex bias remains unclear.

OBJECTIVE

We sought to delineate the contribution of the sex hormone estrogen to the EoE phenotype and esophageal epithelial barrier function and remodeling.

METHODS

We performed demographic and incidence analyses of EoE in male and female subjects from a single-center pediatric cohort. Estrogen-responsive gene expression analyses and estrogen receptor (ESR) immunofluorescence staining of esophageal biopsy specimens from patients with EoE and control subjects were performed. The effect of 17β-estradiol (E2) on IL-13-induced signaling pathways, gene expression, and esophageal epithelial architecture and barrier function in a primary human esophageal keratinocyte cell (EPC2) culture system (EPC2-air-liquid interface) was examined.

RESULTS

We observed a male predominance in patients with EoE. Analyses of RNA sequencing data sets revealed a significant dysregulation of the estrogen-responsive gene network and expression of ESR1 and ESR2 in esophageal biopsy specimens from patients with EoE compared with control subjects. IL-13 stimulation of EPC2-air-liquid interface cells led to altered cellular architecture with induced dilation of intercellular spaces and barrier dysfunction. Pretreatment of EPC2s with E2 prior to IL-13 exposure abrogated IL-13-induced architectural changes and esophageal barrier dysfunction. Mechanistically, E2-protective effects were dependent on ESR2 and associated with diminishing of IL-13-induced tyrosine kinase 2 and signal transducer and activator of transcription 6 phosphorylation and EoE-dysregulated gene expression.

CONCLUSIONS

Estrogen-responsive genes are modified in patients with EoE compared with control subjects. E2 attenuated IL-13-induced architectural changes and esophageal epithelial barrier dysfunction through inhibition of the IL-13/tyrosine kinase 2/signal transducer and activator of transcription 6 pathway via ESR2-dependent process. Estrogen hormone signaling may protect against development of EoE in female subjects.

Effects of 17β-Estradiol on Colonic Permeability and Inflammation in an Azoxymethane/Dextran Sulfate Sodium-Induced Colitis Mouse Model

Background/Aims

Intestinal barrier dysfunction is a hallmark of inflammatory bowel diseases (IBDs) such as ulcerative colitis. This dysfunction is caused by increased permeability and the loss of tight junctions in intestinal epithelial cells. The aim of this study was to investigate whether estradiol treatment reduces colonic permeability, tight junction disruption, and inflammation in an azoxymethane (AOM)/dextran sodium sulfate (DSS) colon cancer mouse model.

Methods

The effects of 17β-estradiol (E2) were evaluated in ICR male mice 4 weeks after AOM/DSS treatment. Histological damage was scored by hematoxylin and eosin staining and the levels of the colonic mucosal cytokine myeloperoxidase (MPO) were assessed by enzyme-linked immunosorbent assay (ELISA). To evaluate the effects of E2 on intestinal permeability, tight junctions, and inflammation, we performed quantitative real-time polymerase chain reaction and Western blot analysis. Furthermore, the expression levels of mucin 2 (MUC2) and mucin 4 (MUC4) were measured as target genes for intestinal permeability, whereas zonula occludens 1 (ZO-1), occludin (OCLN), and claudin 4 (CLDN4) served as target genes for the tight junctions.

Results

The colitis-mediated induced damage score and MPO activity were reduced by E2 treatment (p<0.05). In addition, the mRNA expression levels of intestinal barrier-related molecules (i.e., MUC2, ZO-1, OCLN, and CLDN4) were decreased by AOM/DSS-treatment; furthermore, this inhibition was rescued by E2 supplementation. The mRNA and protein expression of inflammation-related genes (i.e., KLF4, NF-κB, iNOS, and COX-2) was increased by AOM/DSS-treatment and ameliorated by E2.

Conclusions

E2 acts through the estrogen receptor β signaling pathway to elicit anti-inflammatory effects on intestinal barrier by inducing the expression of MUC2 and tight junction molecules and inhibiting pro-inflammatory cytokines.

Fecal incontinence as a moderator between dietary intake and depressive symptoms among a sample of older adults obtained from the National Health and Nutrition Examination Survey (NHANES)

OBJECTIVES

Many studies have established a relationship between diet and mental health, as well as the importance of bowel health. Further, with increased evidence of a gut-brain bidirectional relationship, an indication of dysbiosis as a potential moderator between diet and depression may be a viable target for future interventions. The current study investigated the relationship between diet and depressive symptoms (DS) among older adults, as well as gender, and whether a symptom of dysbiosis, fecal incontinence severity (FIS), moderated this relationship.

METHOD

Using moderated regressions, we examined whether FIS moderates the relationship between diet and DS while controlling for covariates in the overall sample (N = 1918), as well as among the male (n = 841) and female sample (n = 1077). The dietary variables were reduced using a factor analysis.

RESULTS

Results indicated significant moderating effects of FIS between Component 4 and polyunsaturated fatty acids (PFA) in the overall sample. Component 4, protein, carbohydrates, and alcohol were significant in males only while PFA only in females. Further analysis of protein/carbohydrate ratio groups indicated significant differences within males. Higher scores of FIS were related to higher DS and less consumption of Component 4 nutrients, PFA, and protein. Males that consumed higher protein and carbohydrates resulted in lower DS with increased FIS.

CONCLUSION

Outcomes from the current study provide further evidence of the importance of healthy bowel function and the potential of modifying the diet to improve DS in older adults.

Symptoms of menopause - global prevalence, physiology and implications

The symptoms of menopause can be distressing, particularly as they occur at a time when women have important roles in society, within the family and at the workplace. Hormonal changes that begin during the menopausal transition affect many biological systems. Accordingly, the signs and symptoms of menopause include central nervous system-related disorders; metabolic, weight, cardiovascular and musculoskeletal changes; urogenital and skin atrophy; and sexual dysfunction. The physiological basis of these manifestations is emerging as complex and related, but not limited to, oestrogen deprivation. Findings generated mainly from longitudinal population studies have shown that ethnic, geographical and individual factors affect symptom prevalence and severity. Moreover, and of great importance to clinical practice, the latest research has highlighted how certain menopausal symptoms can be associated with the onset of other disorders and might therefore serve as predictors of future health risks in postmenopausal women. The goal of this Review is to describe in a timely manner new research findings on the global prevalence and physiology of menopausal symptoms and their impact on future health.

Effects of Estrogen on the Gastrointestinal Tract

Estrogen is a kind of steroid compound that has extensive biologic activities. The effect of estrogen is pleiotropic, affecting multiple systems in the body. There is accumulating evidence that estrogen has important effects on the gastrointestinal tract. Longer exposure to estrogen may decrease the risk of gastric cancer. Use of the anti-estrogen drug tamoxifen might increase the risk of gastric adenocarcinoma. Estrogen receptor β may serve as a target for colorectal cancer prevention. In addition, estrogen has been reported to be closely related to the mucosal barrier, gastrointestinal function and intestinal inflammation. However, the role of estrogen in the gastrointestinal tract has not been systematically summarized. In this review, we aim to provide an overview of the role of estrogen in the gastrointestinal tract and evaluate it from various aspects, including estrogen receptors, the mucosal barrier, intestinal inflammation and gastrointestinal tract tumors, which may provide the basis for the development of therapeutic strategies to manage gastrointestinal diseases.

Influence of hiatal hernia and male sex on the relationship between alcohol intake and occurrence of Barrett's esophagus

BACKGROUND

The association of alcohol intake with the incidence of Barrett's esophagus (BE) has been inconsistent. Although hiatal hernia and male sex are well-known risk factors of BE, its effect on the association of alcohol intake with the incidence of BE remains unknown.

AIM

To investigate whether the influence of alcohol intake on the occurrence of BE might differ depending on male sex and presence of hiatal hernia.

METHODS

We utilized a database of 8031 patients that underwent upper endoscopy for health screening in a prospective, multicenter, cohort study (the Upper Gastro Intestinal Disease study). The incidence of endoscopic columnar-lined esophagus (eCLE; endoscopically diagnosed BE) was the outcome variable. Multivariable logistic regression analysis was conducted to assess the association between alcohol intake and eCLE stratified by male sex and hiatal hernia, adjusting for clinical features and other potential confounders.

RESULTS

Alcohol intake (≥20 g/day) showed a marginally significant association with the incidence of eCLE in participants without hiatal hernia (0 vs. ≥20 g/day; odds ratio [OR], 1.62; 95% confidence interval [CI], 0.92-2.85, P = 0.09) but not in participants with hiatal hernia (0 vs. ≥20/day; OR, 0.99; 95% CI, 0.59-1.65; P = 0.95). Furthermore, alcohol intake (≥20 g/day) was significantly associated with the incidence of eCLE in male participants without hiatal hernia (0 vs. ≥20 g/day; OR, 1.98; 95% CI, 1.04-4.03; P = 0.04) but not in female participants without hiatal hernia (0 vs. ≥20 g/day; OR, 0.47; 95% CI, 0.03-2.37; P = 0.42).

CONCLUSIONS

The effect of alcohol intake on the incidence of eCLE might be associated with hiatal hernia status and male sex.

Sex and Gender Differences in Gastroesophageal Reflux Disease

It is important to understand sex and gender-related differences in gastroesophageal reflux disease (GERD) because gender-related biologic factors might lead to better prevention and therapy. Non-erosive reflux disease (NERD) affects more women than men. GERD symptoms are more frequent in patients with NERD than in those with reflux esophagitis. However, men suffer pathologic diseases such as reflux esophagitis, Barrett’s esophagus (BE), and esophageal adenocarcinoma (EAC) more frequently than women. The prevalence of reflux esophagitis is significantly increased with age in women, especially after their 50s. The mean age of EAC incidence in women is higher than in men, suggesting a role of estrogen in delaying the onset of BE and EAC. In a chronic rat reflux esophagitis model, nitric oxide was found to be an aggravating factor of esophageal injury in a male-predominant way. In addition, the expression of esophageal occludin, a tight junction protein that plays an important role in the esophageal defense mechanism, was up-regulated in women. This explains the male predominance of reflux esophagitis and delayed incidence of BE or EAC in women. Moreover, the symptoms such as heartburn, regurgitation, and extra-esophageal symptoms have been more frequently reported by women than by men, suggesting that sex and gender play a role in symptom perception. Differential sensitivity with augmented symptoms in women might have diagnostic and therapeutic influence. Furthermore, recent studies have suggested that hormone replacement therapy has a protective effect against esophageal cancer. However, an anti-inflammatory role of estrogen remains compelling, which means further study is necessary in this area.

Differences between older and young patients with autoimmune gastritis

AIM

Elderly patients with autoimmune gastritis might have different symptoms than those of young patients. The aim of the present study was to compare presented symptoms and laboratory parameters associated with autoimmune gastritis in both old and young age groups.

METHODS

A total of 355 patients with autoimmune gastritis were stratified into two groups: 65 years or older (n = 119, mean age 69.47 ± 5.027 years), and under 65 years (n = 236, mean age 45.79 ± 10.51 years). These two groups were then evaluated and compared by means of clinical symptoms, concurrent autoimmune diseases, serum gastrin, vitamin B₁₂ and chromogranin A levels, and the presence of enterochromograffin-like cell hyperplasia.

RESULTS

Among 119 older patients, 35 had dyspeptic symptoms, and 84 patients were referred for vitamin B₁₂ and/or iron deficiency. In the younger group (n = 236), there were more patients who had dyspeptic symptoms (36 vs 200, P < 0.001). Serum gastrin (726.68 ± 266.183 vs 214.36 ± 104.62 pg/mL, P < 0.001) and chromogranin A (301.26 ± 172.95 vs 106.59 ± 67.66 ng/mL, P < 0.001) levels were significantly higher, and the presence of enterochromograffin-like cell hyperplasia was more frequent (113 vs 31, P < 0.001) in older patients than younger patients. Polyautoimmunity (66.3% vs 24.5%) and multiple autoimmune syndrome (17.6% vs 5.5%) were more common in older patients (P < 0.001).

CONCLUSIONS

There are differences in the clinical characteristics and the laboratory parameters between patients with autoimmune gastritis that are older and younger than 65 years-of-age. Elderly patients with autoimmune gastritis were investigated more commonly for vitamin B₁₂ and/or iron deficiency. Polyautoimmunity and multiple autoimmune syndrome were more common, and serum gastrin and chromogranin A levels were significantly higher in older patients. Geriatr Gerontol Int 2017; 17: 1090-1095.

The ageing gastrointestinal tract

PURPOSE OF REVIEW

This article reviews the impact of ageing on the gastrointestinal tract, including effects on the absorption of nutrients and drugs and the gastrointestinal tract defence system against ingested pathogens.

RECENT FINDINGS

Recent publications support earlier observations of an age-related selective decline in gut function including changes in taste, oesophageal sphincter motility, gastric emptying, and neurons of the myenteric plexus related to gut transit which may impact the nutritional status. Ageing is also associated with structural and functional mucosal defence defects, diminished abilities to generate protective immunity, and increased incidence of inflammation and oxidative stress. A number of gastrointestinal disorders occur more frequently in the elderly population.

SUMMARY

Alterations in gut function with ageing have particular implications for oesophageal, gastric, and colonic motility. Older individuals are particularly susceptible to malnutrition, postprandial hypotension, dysphagia, constipation, and faecal incontinence. Decrease in the number of nerve cells of the myenteric plexus that impact digestive absorption and the surface area of the small intestine because of degeneration of villi may lead to blunted absorption of nutrients. Impairment of the intestinal immune system as a result of ageing, including the mucosal layer of the gastrointestinal tract, appears to be a significant contributor to the age-related increase in the incidence and severity of infections.

The microbiome and autoimmune disease: Report from a Noel R. Rose Colloquium

Although the mechanisms by which the human microbiome influences the onset and progression of autoimmune diseases remain to be determined, established animal models of autoimmune diseases indicate that local and systemic bidirectional interactions with the microbiome play a signaling or promoting role through the immune system. Whether alterations in the microbiome are a pathogenic cause or simply an effect of inflammation and autoimmune disease remains an essential question to be addressed in disease-specific research, as well as whether particular conditions of the microbiome promote health or promote disease. Future research in this area needs to account for sex differences in microbiome composition because autoimmune diseases disproportionately affect women. Probiotic and other treatments that manipulate assemblage of the microbiome may offer methods of preventing or mitigating the effects of autoimmune disease.