Gut microbiota-derived short-chain fatty acids protect against the progression of endometriosis

Association Between the Oxidative Balance Score and Endometriosis: A Population-Based Study

Purpose

To investigate the association between the oxidative balance score (OBS) and endometriosis.

Methods

This cross-sectional study used four cycles of the National Health and Nutrition Examination Survey (NHANES) (1999-2000, 2001-2002, 2003-2004, and 2005-2006). OBS involved 16 dietary nutrients and 4 lifestyle factors, including 5 pro-oxidants and 15 anti-oxidants. According to weighted quartiles, the OBS was divided into four categories: < 12.54, 12.54-18.70, 18.71-24.68, and > 24.68. Endometriosis was diagnosed based on a question from the reproductive health questionnaire. Weighted multivariate logistic analysis was used to investigate the association between OBS and endometriosis. Subgroup analysis was performed based on menstrual regularity and female hormone use.

Results

A total of 5095 women were included, with 1140 (22.37%), 1232 (24.18%), 1224 (24.02%), and 1499 (29.42%) women in the OBS < 12.54, of 12.54-18.70, of 18.71-24.68, and > 24.68 categories, respectively. After adjusting age, race, family poverty-to-income ratio (PIR), education level, uterine fibroids, menstrual regularity, oophorectomy, female hormone use, hypertension, dyslipidemia, and steroid drug, a high OBS (> 24.68) was found to be associated with lower odds of endometriosis [odds ratio (OR) = 0.70, 95% confidence interval (CI): 0.50-0.97, P = 0.033] compared to a low OBS (< 12.54). The similar result was also found in women with irregular menstruation (OR = 0.58, 95% CI: 0.37-0.91, P = 0.020) and with female hormone use (OR = 0.71, 95% CI: 0.52-0.98, P = 0.037).

Conclusion

A high OBS was associated with lower odds of endometriosis, especially in women with irregular menstruation and female hormone use.

Unraveling the relationship between gut microbiota and site-specific endometriosis: a Mendelian randomization analysis

Background

Although numerous studies have illustrated the connection between gut microbiota and endometriosis, a conspicuous gap exists in research focusing on the pathogenesis of endometriosis at various sites and its linkage with infertility.

Methods

In this study, we used a two-sample Mendelian randomization analysis to investigate the effect of gut microbiota on the development of endometriosis in different regions, including the uterus, ovary, fallopian tube, pelvic peritoneum, vagina, and rectovaginal septum, as well as the intestine. Additionally, we explored the correlation between gut microbiota and endometriosis-induced infertility. Genetic associations with gut microbes were obtained from genome-wide association study (GWAS) datasets provided by the MiBioGen consortium, whereas endometriosis-related GWAS data were sourced from the FinnGen dataset. In our analysis, single-nucleotide polymorphisms were used as instrumental variables, with the primary estimation of the causal effect performed via the inverse variance weighting method. Our sensitivity analyses incorporated heterogeneity tests, pleiotropy tests, and the leave-one-out method.

Results

We identified associations at the genus level between four bacterial communities and endometriosis. Subsequently, several associations between the gut microbiota and various subtypes of endometriosis at different anatomical sites were recognized. Specifically, three genera were linked with ovarian endometriosis, six genera were associated with tubal endometriosis, four genera showed links with pelvic peritoneum endometriosis, five genera were connected with vaginal and rectovaginal septum endometriosis, and seven genera demonstrated linkages with intestinal endometriosis. Additionally, one genus was associated with adenomyosis, and three genera exhibited associations with endometriosis-induced infertility.

Conclusion

Our study elucidates associations between gut microbiota and site-specific endometriosis, thereby augmenting our understanding of the pathophysiology of endometriosis. Moreover, our findings pave the way for potential therapeutic strategies targeting gut microbiota for individuals grappling with endometriosis-related infertility.

Endometriosis is a disease of immune dysfunction, which could be linked to microbiota

Background: Endometriosis, characterized by extrauterine endometrial tissue, leads to irregular bleeding and pelvic pain. Menstrual retrograde theory suggests fragments traverse fallopian tubes, causing inflammation and scar tissue. Prevalent among infertile women, risk factors include fewer pregnancies, delayed childbirth, irregular cycles, and familial predisposition. Treatments, medication, and surgery entail side effects. Studies link gut microbiota alterations to endometriosis, necessitating research to establish causation. We used Mendelian randomization to investigate the potential link between endometriosis and gut microbiota through genetic variants. Methods: Two-sample Mendelian randomization analyzed gut microbiota's potential causal effects on endometriosis. Instrumental variables, robustly associated with exposures, leveraged GWAS data from MiBioGen for gut microbiota and FinnGen R8 release for endometriosis. SNPs strongly associated with exposures were instrumental variables. Rigorous assessments ensured SNP impact scrutiny on endometriosis. Results: At the genus level, Anaerotruncus, Desulfovibrio, Haemophilus, and Holdemania showed causal association with endometriosis. Specific gut microbiota exhibited causal effects on different endometriosis stages. Holdemania and Ruminococcaceae UCG002 exerted reversible, stage-specific impacts. Conclusion: Mendelian randomization provides evidence for the causal link between specific gut microbiotas and endometriosis, emphasizing the pivotal role of gut microbiota dysbiosis. Modulating gut microbiota emerges as a promising strategy for preventing and treating endometriosis.

Effects of the gut microbiota and its metabolite short-chain fatty acids on endometriosis

In recent years, a growing body of research has confirmed that the gut microbiota plays a major role in the maintenance of human health and disease. A gut microbiota imbalance can lead to the development of many diseases, such as pregnancy complications, adverse pregnancy outcomes, polycystic ovary syndrome, endometriosis, and cancer. Short-chain fatty acids are metabolites of specific intestinal bacteria and are crucial for maintaining intestinal homeostasis and regulating metabolism and immunity. Endometriosis is the result of cell proliferation, escape from immune surveillance, and invasive metastasis. There is a strong correlation between the anti-proliferative and anti-inflammatory effects of short-chain fatty acids produced by gut microbes and the development of endometriosis. Given that the mechanism of action of gut microbiota and Short-chain fatty acids in endometriosis remain unclear, this paper aims to provide a comprehensive review of the complex interactions between intestinal flora, short-chain fatty acids and endometriosis. In addition, we explored potential microbial-based treatment strategies for endometriosis, providing new insights into the future development of diagnostic tests and prevention and treatment methods for endometriosis.

Endometriosis, Pain, and Related Psychological Disorders: Unveiling the Interplay among the Microbiome, Inflammation, and Oxidative Stress as a Common Thread

Endometriosis (EM), a chronic condition in endometrial tissue outside the uterus, affects around 10% of reproductive-age women, significantly affecting fertility. Its prevalence remains elusive due to the surgical confirmation needed for diagnosis. Manifesting with a range of symptoms, including dysmenorrhea, dyschezia, dysuria, dyspareunia, fatigue, and gastrointestinal discomfort, EM significantly impairs quality of life due to severe chronic pelvic pain (CPP). Psychological manifestations, notably depression and anxiety, frequently accompany the physical symptoms, with CPP serving as a key mediator. Pain stems from endometrial lesions, involving oxidative stress, neuroinflammation, angiogenesis, and sensitization processes. Microbial dysbiosis appears to be crucial in the inflammatory mechanisms underlying EM and associated CPP, as well as psychological symptoms. In this scenario, dietary interventions and nutritional supplements could help manage EM symptoms by targeting inflammation, oxidative stress, and the microbiome. Our manuscript starts by delving into the complex relationship between EM pain and psychological comorbidities. It subsequently addresses the emerging roles of the microbiome, inflammation, and oxidative stress as common links among these abovementioned conditions. Furthermore, the review explores how dietary and nutritional interventions may influence the composition and function of the microbiome, reduce inflammation and oxidative stress, alleviate pain, and potentially affect EM-associated psychological disorders.

The impact of the microbiota-gut-brain axis on endometriosis-associated symptoms: mechanisms and opportunities for personalised management strategies

Endometriosis is a chronic inflammatory condition affecting one in 10 women and those assigned female at birth, defined by the presence of endometrial-like tissue outside the uterus. It is commonly associated with pain, infertility, and mood disorders, and often comorbid with other chronic pain conditions, such as irritable bowel syndrome. Recent research has identified a key role for the microbiota-gut-brain axis in health and a range of inflammatory and neurological disorders, prompting an exploration of its potential mechanistic role in endometriosis. Increased awareness of the impact of the gut microbiota within the patient community, combined with the often-detrimental side effects of current therapies, has motivated many to utilise self-management strategies, such as dietary modification and supplements, despite a lack of robust clinical evidence. Current research has characterised the gut microbiota in endometriosis patients and animal models. However, small cohorts and differing methodology has resulted in little consensus in the data. In this narrative review, we summarise research studies that have investigated the role of gut microbiota and their metabolic products in the development and progression of endometriosis lesions, before summarising insights from research into co-morbid conditions and discussing the reported impact of self-management strategies on symptoms of endometriosis. Finally, we suggest ways in which this promising field of research could be expanded to explore the role of specific bacteria, improve access to 'microbial' phenotyping, and to develop personalised patient advice for reduction of symptoms such as chronic pain and bloating.

Short-chain fatty acids: linking diet, the microbiome and immunity

The short-chain fatty acids (SCFAs) butyrate, propionate and acetate are microbial metabolites and their availability in the gut and other organs is determined by environmental factors, such as diet and use of antibiotics, that shape the diversity and metabolism of the microbiota. SCFAs regulate epithelial barrier function as well as mucosal and systemic immunity via evolutionary conserved processes that involve G protein-coupled receptor signalling or histone deacetylase activity. Indicatively, the anti-inflammatory role of butyrate is mediated through direct effects on the differentiation of intestinal epithelial cells, phagocytes, B cells and plasma cells, and regulatory and effector T cells. Intestinally derived SCFAs also directly and indirectly affect immunity at extra-intestinal sites, such as the liver, the lungs, the reproductive tract and the brain, and have been implicated in a range of disorders, including infections, intestinal inflammation, autoimmunity, food allergies, asthma and responses to cancer therapies. An ecological understanding of microbial communities and their interrelated metabolic states, as well as the engineering of butyrogenic bacteria may support SCFA-focused interventions for the prevention and treatment of immune-mediated diseases.

Harnessing the power within: engineering the microbiome for enhanced gynecologic health

Graphical abstract

Abstract

Although numerous studies have demonstrated the impact of microbiome manipulation on human health, research on the microbiome's influence on female health remains relatively limited despite substantial disease burden. In light of this, we present a selected review of clinical trials and preclinical studies targeting both the vaginal and gut microbiomes for the prevention or treatment of various gynecologic conditions. Specifically, we explore studies that leverage microbiota transplants, probiotics, prebiotics, diet modifications, and engineered microbial strains. A healthy vaginal microbiome for females of reproductive age consists of lactic acid-producing bacteria predominantly of the Lactobacillus genus, which serves as a protective barrier against pathogens and maintains a balanced ecosystem. The gut microbiota's production of short-chain fatty acids, metabolism of primary bile acids, and modulation of sex steroid levels have significant implications for the interplay between host and microbes throughout the body, ultimately impacting reproductive health. By harnessing interventions that modulate both the vaginal and gut microbiomes, it becomes possible to not only maintain homeostasis but also mitigate pathological conditions. While the field is still working toward making broad clinical recommendations, the current studies demonstrate that manipulating the microbiome holds great potential for addressing diverse gynecologic conditions.

Lay summary

Manipulating the microbiome has recently entered popular culture, with various diets thought to aid the microbes that live within us. These microbes live in different locations of our body and accordingly help us digest food, modulate our immune system, and influence reproductive health. The role of the microbes living in and influencing the female reproductive tract remains understudied despite known roles in common conditions such as vulvovaginal candidiasis (affecting 75% of females in their lifetime), bacterial vaginosis (25% of females in their lifetime), cervical HPV infection (80% of females in their lifetime), endometriosis (6-10% of females of reproductive age), and polycystic ovary syndrome (10-12% of females of reproductive age). Here, we review four different approaches used to manipulate the female reproductive tract and gastrointestinal system microbiomes: microbiota transplants, probiotics, prebiotics, and dietary interventions, and the use of engineered microbial strains. In doing so, we aim to stimulate discussion on new ways to understand and treat female reproductive health conditions.

Exploring the Role of G Protein Expression in Sodium Butyrate-Enhanced Pancreas Development of Dairy Calves: A Proteomic Perspective

The present study evaluated the effects of sodium butyrate (SB) supplementation on exocrine and endocrine pancreatic development in dairy calves. Fourteen male Holstein calves were alimented with either milk or milk supplemented with SB for 70 days. Pancreases were collected for analysis including staining, immunofluorescence, electron microscopy, qRT-PCR, Western blotting, and proteomics. Results indicated increased development in the SB group with increases in organ size, protein levels, and cell growth. There were also exocrine enhancements manifested as higher enzyme activities and gene expressions along with larger zymogen granules. Endocrine benefits included elevated gene expression, more insulin secretion, and larger islets, indicating a rise in β-cell proliferation. Proteomics and pathway analyses pinpointed the G protein subunit alpha-15 as a pivotal factor in pancreatic and insulin secretion pathways. Overall, SB supplementation enhances pancreatic development by promoting its exocrine and endocrine functions through G protein regulation in dairy calves.

Role of the gut microbiota in the pathogenesis of endometriosis: a review

Endometriosis is classically defined as a chronic inflammatory heterogeneous disorder occurring in any part of the body, characterized by estrogen-driven periodic bleeding, proliferation, and fibrosis of ectopic endometrial glands and stroma outside the uterus. Endometriosis can take overwhelmingly serious damage to the structure and function of multi-organ, even impair whole-body systems, resulting in severe dysmenorrhea, chronic pelvic pain, infertility, fatigue and depression in 5-10% women of reproductive age. Precisely because of a huge deficiency of cognition about underlying etiology and complex pathogenesis of the debilitating disease, early diagnosis and treatment modalities with relatively minor side effects become bottlenecks in endometriosis. Thus, endometriosis warrants deeper exploration and expanded investigation in pathogenesis. The gut microbiota plays a significant role in chronic diseases in humans by acting as an important participant and regulator in the metabolism and immunity of the body. Increasingly, studies have shown that the gut microbiota is closely related to inflammation, estrogen metabolism, and immunity resulting in the development and progression of endometriosis. In this review, we discuss the diverse mechanisms of endometriosis closely related to the gut microbiota in order to provide new approaches for deeper exploration and expanded investigation for endometriosis on prevention, early diagnosis and treatment.

Unraveling the microbial puzzle: exploring the intricate role of gut microbiota in endometriosis pathogenesis

Endometriosis (EMs) is a prevalent gynecological disorder characterized by the growth of uterine tissue outside the uterine cavity, causing debilitating symptoms and infertility. Despite its prevalence, the exact mechanisms behind EMs development remain incompletely understood. This article presents a comprehensive overview of the relationship between gut microbiota imbalance and EMs pathogenesis. Recent research indicates that gut microbiota plays a pivotal role in various aspects of EMs, including immune regulation, generation of inflammatory factors, angiopoietin release, hormonal regulation, and endotoxin production. Dysbiosis of gut microbiota can disrupt immune responses, leading to inflammation and impaired immune clearance of endometrial fragments, resulting in the development of endometriotic lesions. The dysregulated microbiota can contribute to the release of lipopolysaccharide (LPS), triggering chronic inflammation and promoting ectopic endometrial adhesion, invasion, and angiogenesis. Furthermore, gut microbiota involvement in estrogen metabolism affects estrogen levels, which are directly related to EMs development. The review also highlights the potential of gut microbiota as a diagnostic tool and therapeutic target for EMs. Interventions such as fecal microbiota transplantation (FMT) and the use of gut microbiota preparations have demonstrated promising effects in reducing EMs symptoms. Despite the progress made, further research is needed to unravel the intricate interactions between gut microbiota and EMs, paving the way for more effective prevention and treatment strategies for this challenging condition.

The effect of the female genital tract and gut microbiome on reproductive dysfunction

Microorganisms are ubiquitous in the human body; they are present in various areas including the gut, mouth, skin, respiratory tract, and reproductive tract. The interaction between the microbiome and reproductive health has become an increasingly compelling area of study. Disruption of the female genital tract microbiome can significantly impact the metabolism of amino acids, carbohydrates, and lipids, increasing susceptibility to reproductive tract diseases such as vaginitis, chronic endometritis, endometrial polyps, endometriosis, and polycystic ovary syndrome. The gut microbiome, considered an endocrine organ, plays a crucial role in the reproductive endocrine system by interacting with hormones like estrogen and androgens. Imbalances in the gut microbiome composition can lead to various diseases and conditions, including polycystic ovary syndrome, endometriosis, and cancer, although research on their mechanisms remains limited. This review highlights the latest advancements in understanding the female genital tract and gut microbiomes in gynecological diseases. It also explores the potential of microbial communities in the treatment of reproductive diseases. Future research should focus on identifying the molecular mechanisms underlying the association between the microbiome and reproductive diseases to develop new and effective strategies for disease prevention, diagnosis, and treatment related to female reproductive organs.

Emerging bacterial factors for understanding pathogenesis of endometriosis

The pathogenesis of endometriosis is a complex process, and recent research has introduced novel hypotheses in this field. This review summarizes recent studies on the pathogenesis of endometriosis. We focused on several classical hypotheses, as well as their interactions with the microenvironment of hormonal dependence and immunosuppression. Furthermore, we highlighted the emergence of bacterial factors associated with endometriosis. Recent advances in next-generation sequencing (NGS) have revealed the presence and detailed distribution of these bacteria as well as the involvement of specific bacteria in pathogenesis. These factors alter the microenvironment in the early stages of endometriosis development, leading to lesion formation. Understanding the mechanisms underlying the early development of endometriosis from a new perspective would be helpful for the development of novel therapeutic agents for endometriosis.

SGLT2 inhibitors and AMPK: The road to cellular housekeeping?

Sodium-glucose co-transporter-2 (SGLT2) inhibitors, known as Gliflozins, are a class of Glucose-lowering drugs in adults with type 2 diabetes (T2D) that induce glucosuria by blocking SGLT2 co-transporters in the proximal tubules. Several lines of evidence suggest that SGLT2 inhibitors regulate multiple mechanisms associated with the regulation of varying cellular pathways. The 5'-adenosine monophosphate-activated protein kinase (AMPK) pathway plays an important role in metabolic homeostasis by influencing cellular processes. Recently, it has been shown that SGLT2 inhibitors can affect the AMPK pathway in differing physiological and pathological ways, resulting in kidney, intestinal, cardiovascular, and liver protective effects. Additionally, they have therapeutic effects on nonalcoholic fatty liver disease and diabetes mellitus-associated complications. In this review, we summarize the results of studies of AMPK-associated therapeutic effects of SGLT2 inhibitors in different organelle functions.

Causal effects of gut microbiome on endometriosis: a two-sample mendelian randomization study

BACKGROUND

Previous studies have shown observational associations between the gut microbiota and endometriosis; however, the causal nature of such associations remains unclear. This study aimed to analyze the genetic causal relationship between the two.

METHODS

A gut microbiome genome-wide association study conducted by the MiBioGen consortium was used as exposure data, and summary statistics of endometriosis were obtained from the FinnGen consortium R8 release data. Inverse variance weighted, MR-Egger, weighted median, weighted model, and simple model analyses were applied to examine the causal relationship, and sensitivity analyses were conducted to validate the robustness of the results.

RESULTS

The results showed that, out of 211 gut microbiome taxa, Clostridiales_vadin_BB60_group, Oxalobacteraceae, Desulfovibrio, Haemophilus, and Holdemania had protective effects on endometriosis, while Porphyromonadaceae and Anaerotruncus might contribute to the development of endometriosis. Heterogeneity and pleiotropy analyses confirmed the robustness of the results.

CONCLUSION

The two-sample Mendelian randomization analysis conducted in this study identified specific intestinal flora with a causal relationship with endometriosis at the genetic level, offering new insights into the gut microbiota-mediated development mechanism of endometriosis.

Microbiota Transplant and Gynecological Disorders: The Bridge between Present and Future Treatments

Fecal microbiota transplantation (FMT) is a procedure that involves transferring fecal bacteria from a healthy donor to a patients' intestines to restore gut-immunity homeostasis. While FMT was primarily supposed to treat gastrointestinal disorders such as inflammatory bowel disease and irritable bowel syndrome-and especially Clostridium difficile infection (currently the only used as clinical treatment)-recent research has suggested that it may also become a potential treatment for gynecological disorders, including endometriosis and polycystic ovary syndrome (PCOS). On the contrary, vaginal microbiota transplantation (VMT) is a newer and less commonly used procedure than the FMT approach, and its potential applications are still being explored. It involves direct grafting of the entire vaginal microbiota of healthy women into the vaginal tract of patients to easily rebuild the local microbiota environment, restoring vaginal eubiosis and relieving symptoms. Like FMT, VMT is thought to have potential in treating different microbiota-related conditions. In fact, many gynecological disorders, such as bacterial vaginosis and vulvovaginal candidiasis, are thought to be caused by an imbalance in the vaginal microbiota. In this review, we will summarize the development, current challenges, and future perspectives of microbiota transplant, with the aim of exploring new strategies for its employment as a promising avenue for treating a broad range of gynecological diseases.

The impact of microbiota-derived short-chain fatty acids on macrophage activities in disease: Mechanisms and therapeutic potentials

Short-chain fatty acids (SCFAs) derived from the fermentation of carbohydrates by gut microbiota play a crucial role in regulating host physiology. Among them, acetate, propionate, and butyrate are key players in various biological processes. Recent research has revealed their significant functions in immune and inflammatory responses. For instance, butyrate reduces the development of interferon-gamma (IFN-γ) generating cells while promoting the development of regulatory T (Treg) cells. Propionate inhibits the initiation of a Th2 immune response by dendritic cells (DCs). Notably, SCFAs have an inhibitory impact on the polarization of M2 macrophages, emphasizing their immunomodulatory properties and potential for therapeutics. In animal models of asthma, both butyrate and propionate suppress the M2 polarization pathway, thus reducing allergic airway inflammation. Moreover, dysbiosis of gut microbiota leading to altered SCFA production has been implicated in prostate cancer progression. SCFAs trigger autophagy in cancer cells and promote M2 polarization in macrophages, accelerating tumor advancement. Manipulating microbiota- producing SCFAs holds promise for cancer treatment. Additionally, SCFAs enhance the expression of hypoxia-inducible factor 1 (HIF-1) by blocking histone deacetylase, resulting in increased production of antibacterial effectors and improved macrophage-mediated elimination of microorganisms. This highlights the antimicrobial potential of SCFAs and their role in host defense mechanisms. This comprehensive review provides an in-depth analysis of the latest research on the functional aspects and underlying mechanisms of SCFAs in relation to macrophage activities in a wide range of diseases, including infectious diseases and cancers. By elucidating the intricate interplay between SCFAs and macrophage functions, this review aims to contribute to the understanding of their therapeutic potential and pave the way for future interventions targeting SCFAs in disease management.

Gut and reproductive tract microbiota: Insights into the pathogenesis of endometriosis (Review)

Endometriosis is characterized by the presence of endometrial-like tissue outside the uterus and is associated with an inflammatory immune response. The gut and reproductive tract microbiota constitute a protective barrier against infection by pathogens and regulate inflammatory and immune functions. This review summarizes microbiota imbalance (i.e., dysbiosis) in endometriosis and discusses how dysbiosis influences disease development. The literature was searched for studies published from inception to March 2022 in the PubMed and Google Scholar databases using a combination of specific terms. An altered gut and reproductive tract microbiome has been reported in numerous conditions, such as inflammatory bowel disease, allergies, autoimmunity, cancer and reproductive disorders (e.g., endometriosis). Furthermore, microbial dysbiosis is a hallmark of endometriosis and is characterized by a decrease in beneficial probiotics and an increase in pathogenic microbes, which leads to a series of estrobolomic and metabolomic changes. Gut or reproductive tract microbiome dysbiosis was reported in mice, nonhuman primates, and females with endometriosis. Animal models of endometriosis demonstrated the effects of the gut microbiome on lesion growth and vice versa. The immune system mediated by the microbiota-gut-reproductive tract axis triggers an inflammatory response that damages reproductive tract tissue, which possibly leads to endometriosis. However, whether the alteration of eubiosis (a balanced microbiota) to dysbiosis is a cause or a result of endometriosis is unclear. In conclusion, this review provides an overview of the relationship between the gut and reproductive tract microbiome and endometriosis, focusing on the mechanisms by which dysbiosis may increase the risk of disease.

How Do Microorganisms Influence the Development of Endometriosis? Participation of Genital, Intestinal and Oral Microbiota in Metabolic Regulation and Immunopathogenesis of Endometriosis

Microorganisms inhabiting the human body play an extremely key role in its proper functioning, as well as in the development of the immune system, which, by maintaining the immune balance, allows you to enjoy health. Dysbiosis of the intestinal microbiota, or in the oral cavity or reproductive tract, understood as a change in the number and diversity of all microorganisms inhabiting them, may correlate with the development of many diseases, including endometriosis, as researchers have emphasized. Endometriosis is an inflammatory, estrogen-dependent gynecological condition defined by the growth of endometrial cells outside the uterine cavity. Deregulation of immune homeostasis resulting from microbiological disorders may generate chronic inflammation, thus creating an environment conducive to the increased adhesion and angiogenesis involved in the development of endometriosis. In addition, research in recent years has implicated bacterial contamination and immune activation, reduced gastrointestinal function by cytokines, altered estrogen metabolism and signaling, and abnormal progenitor and stem cell homeostasis, in the pathogenesis of endometriosis. The aim of this review was to present the influence of intestinal, oral and genital microbiota dysbiosis in the metabolic regulation and immunopathogenesis of endometriosis.

The Impact of Histone Modifications in Endometriosis Highlights New Therapeutic Opportunities

Endometriosis is a chronic disorder of the female reproductive system which afflicts a great number of women worldwide. Histone deacetylases (HDACs) prevent the relaxation of chromatin, thereby positively or negatively modulating gene transcription. The current review aims at studying the impact of histone modifications and their therapeutic targeting in endometriosis. In order to identify relevant studies, a literature review was conducted using the MEDLINE and LIVIVO databases. The current manuscript represents the most comprehensive, up-to-date review of the literature focusing on the particular role of HDACs and their inhibitors in the context of endometriosis. HDAC1, HDAC2, HDAC3, Sirtuin 1, and Sirtuin 3, are the five most studied HDAC enzymes which seem to, at least partly, influence the pathophysiology of endometriosis. Both well-established and novel HDACIs could possibly represent modern, efficacious anti-endometriotic drug agents. Altogether, histone modifications and their therapeutic targeting have been proven to have a strong impact on endometriosis.

Gut microbiota and microbiota-derived metabolites promotes endometriosis

Endometriosis is a pathological condition of the female reproductive tract characterized by the existence of endometrium-like tissue at ectopic sites, affecting 10% of women between the age 15 and 49 in the USA. However, currently there is no reliable non-invasive method to detect the presence of endometriosis without surgery and many women find hormonal therapy and surgery as ineffective in avoiding the recurrences. There is a lack of knowledge on the etiology and the factors that contribute to the development of endometriosis. A growing body of recent evidence suggests an association between gut microbiota and endometriosis pathophysiology. However, the direct impact of microbiota and microbiota-derived metabolites on the endometriosis disease progression is largely unknown. To understand the causal role of gut microbiota and endometriosis, we have implemented a novel model using antibiotic-induced microbiota-depleted (MD) mice to investigate the endometriosis disease progression. Interestingly, we found that MD mice showed reduced endometriotic lesion growth and, the transplantation of gut microbiota by oral gavage of feces from mice with endometriosis rescued the endometriotic lesion growth. Additionally, using germ-free donor mice, we indicated that the uterine microbiota is dispensable for endometriotic lesion growth in mice. Furthermore, we showed that gut microbiota modulates immune cell populations in the peritoneum of lesions-bearing mice. Finally, we found a novel signature of microbiota-derived metabolites that were significantly altered in feces of mice with endometriosis. Finally, we found one the altered metabolite, quinic acid promoted the survival of endometriotic epithelial cells in vitro and lesion growth in vivo, suggesting the disease-promoting potential of microbiota-derived metabolites. In summary, these data suggest that gut microbiota and microbiota-derived metabolome contribute to lesion growth in mice, possibly through immune cell adaptations. Of translational significance, these findings will aid in designing non-invasive diagnostics using stool metabolites for endometriosis.

Amyotrophic Lateral Sclerosis Pathoetiology and Pathophysiology: Roles of Astrocytes, Gut Microbiome, and Muscle Interactions via the Mitochondrial Melatonergic Pathway, with Disruption by Glyphosate-Based Herbicides

The pathoetiology and pathophysiology of motor neuron loss in amyotrophic lateral sclerosis (ALS) are still to be determined, with only a small percentage of ALS patients having a known genetic risk factor. The article looks to integrate wider bodies of data on the biological underpinnings of ALS, highlighting the integrative role of alterations in the mitochondrial melatonergic pathways and systemic factors regulating this pathway across a number of crucial hubs in ALS pathophysiology, namely glia, gut, and the muscle/neuromuscular junction. It is proposed that suppression of the mitochondrial melatonergic pathway underpins changes in muscle brain-derived neurotrophic factor, and its melatonergic pathway mimic, N-acetylserotonin, leading to a lack of metabolic trophic support at the neuromuscular junction. The attenuation of the melatonergic pathway in astrocytes prevents activation of toll-like receptor agonists-induced pro-inflammatory transcription factors, NF-kB, and yin yang 1, from having a built-in limitation on inflammatory induction that arises from their synchronized induction of melatonin release. Such maintained astrocyte activation, coupled with heightened microglia reactivity, is an important driver of motor neuron susceptibility in ALS. Two important systemic factors, gut dysbiosis/permeability and pineal melatonin mediate many of their beneficial effects via their capacity to upregulate the mitochondrial melatonergic pathway in central and systemic cells. The mitochondrial melatonergic pathway may be seen as a core aspect of cellular function, with its suppression increasing reactive oxygen species (ROS), leading to ROS-induced microRNAs, thereby altering the patterning of genes induced. It is proposed that the increased occupational risk of ALS in farmers, gardeners, and sportsmen and women is intimately linked to exposure, whilst being physically active, to the widely used glyphosate-based herbicides. This has numerous research and treatment implications.

Subchronic exposure to environmentally relevant concentrations of di-(2-ethylhexyl) phthalate differentially affects the colon and ileum in adult female mice

Di(2-ethylhexyl) phthalate (DEHP) is a large-molecular-weight phthalate added to plastics to impart versatile properties. DEHP can be found in medical equipment and devices, food containers, building materials, and children's toys. Although DEHP exposure occurs most commonly by ingesting contaminated foods in the majority of the population, its effects on the gastrointestinal tract have not been well studied. Therefore, we analyzed the effects of subchronic exposure to DEHP on the ileum and colon morphology, gene expression, and immune microenvironment. Adult C57BL/6 female mice were orally dosed with corn oil (control, n = 7) or DEHP (0.02, 0.2, or 30 mg/kg, n = 7/treatment dose) for 30-34 days. Mice were euthanized during diestrus, and colon and ileum tissues were collected for RT-qPCR and immunohistochemistry. Subchronic DEHP exposure in the ileum altered the expression of several immune-mediating factors (Muc1, Lyz1, Cldn1) and cell viability factors (Bcl2 and Aifm1). Similarly, DEHP exposure in the colon impacted the gene expression of factors involved in mediating immune responses (Muc3a, Zo2, Ocln, Il6, and Il17a); and also altered the expression of cell viability factors (Ki67, Bcl2, Cdk4, and Aifm1) as well as a specialized epithelial cell marker (Vil1). Immunohistochemical analysis of the ileum showed DEHP increased expression of VIL1, CLDN1, and TNF and decreased number of T-cells in the villi. Histological analysis of the colon showed DEHP altered morphology and reduced cell proliferation. Moreover, in the colon, DEHP increased the expression of MUC2, MUC1, VIL1, CLDN1, and TNF. DEHP also increased the number of T-cells and Type 2 immune cells in the colon. These data suggest that subchronic DEHP exposure differentially affects the ileum and colon and alters colonic morphology and the intestinal immune microenvironment. These results have important implications for understanding the effects of DEHP on the gastrointestinal system.

The gut microbiota and endometriosis: From pathogenesis to diagnosis and treatment

Endometriosis is a common gynecological disease, that often leads to pain and infertility. At present, the specific pathogenesis of endometriosis has not been clarified, but it may be closely related to an imbalance of sex hormones in the body, ectopic hyperplasia stimulated by immune inflammation, and invasion and escape based on tumor characteristics. Gut microbiota is associated with many inflammatory diseases. With the further study of the gut microbiota, people are paying increasing attention to its relationship with endometriosis. Studies have shown that there is an association between the gut microbiota and endometriosis. The specific ways and mechanisms by which the gut microbiota participates in endometriosis may involve estrogen, immune inflammation, and tumor characteristics, among others. Therefore, in the future, regulating gut microbiota disorders in various ways can help in the treatment of endometriosis patients. This study reviewed the research on the gut microbiota and endometriosis in order to provide ideas for clinical diagnosis and treatment.

The impact of herbal medicine in regulating intestinal flora on female reproductive disorders

As an important part of the human intestinal microecology, the intestinal flora is involved in a number of physiological functions of the host. Several studies have shown that imbalance of intestinal flora and its regulation of the intestinal barrier, intestinal immune response, and intestinal flora metabolites (short-chain fatty acids and bile acids) can affect the development and regression of female reproductive disorders. Herbal medicine has unique advantages in the treatment of female reproductive disorders such as polycystic ovary syndrome, endometriosis and premature ovarian insufficiency, although its mechanism of action is still unclear. Therefore, based on the role of intestinal flora in the occurrence and development of female reproduction-related diseases, the progress of research on the diversity, structure and composition of intestinal flora and its metabolites regulated by botanical drugs, Chinese herbal formulas and active ingredients of Chinese herbal medicines is reviewed, with a view to providing reference for the research on the mechanism of action of Chinese herbal medicines in the treatment of female reproductive disorders and further development of new herbal medicines.

Female reproductive dysfunctions and the gut microbiota

The gut microbiome is considered an endocrine organ that can influence distant organs and associated biological pathways. Recent advances suggest that gut microbial homeostasis is essential for reproductive health and that perturbations in the gut microbiota can lead to reproductive pathologies. This review provides an updated overview of the relationship between the gut microbiome and female reproductive diseases. Specifically, we highlight the most recent findings on the gut microbiome in gynecological pathologies including polycystic ovarian syndrome, endometriosis, and endometrial cancer. Most studies revealed associations between altered gut microbial compositions and these reproductive diseases, though few have suggested cause-effect relationships. Future studies should focus on determining the molecular mechanisms underlying associations between gut microbiota and reproductive diseases. Understanding this bidirectional relationship could lead to the development of novel and effective strategies to prevent, diagnose, and treat female reproductive organ-related diseases.

Association between Endometriosis, Irritable Bowel Syndrome and Eating Disorders: ENDONUT Pilot Study

Background and aim: Irritable bowel syndrome (IBS), eating disorders (ED) and endometriosis share common pathophysiological mechanisms, involving alterations of the gut−brain axis. The aim of the ENDONUT pilot study was to investigate an association between these three diseases by screening for IBS and ED in patients with endometriosis. Method: We included patients from the CIRENDO cohort (Inter-Regional North-West Cohort of women with ENDOmetriosis) with a recent documented diagnosis of endometriosis of less than 4 years, regardless of age, date of onset of symptoms, type of endometriosis (digestive or not), with or without endometriosis-related digestive surgery. Validated questionnaires were used to screen for IBS (Rome IV, Francis score), ED (SCOFF-F, EAT-26), and anxiety/depression (HAD). Anthropometric data and lifestyle habits were also collected. The primary composite endpoint was SCOFF-F and ROME-IV scores. Results: Among 100 patients meeting inclusion criteria, 54 patients completed all the questionnaires. Of these, 19 had a positive SCOFF-F score (35.2%), 26 had a positive ROME-IV score (48.1%), and 14 patients (25.9%) had both a positive SCOFF-F score and a positive ROME-IV score (p = 0.006). Patients with positive SCOFF-F and ROME-IV scores had significantly higher HAD-anxiety and depression scores (p < 0.05). Conclusion: These results suggest a significant association between IBS, ED and endometriosis. The prevalence of IBS and ED in our population is higher than in the general population. Larger studies are needed to confirm these results, to better understand this triad, and to improve the diagnostic and multidisciplinary therapeutic management of these patients.

The experiences of endometriosis patients with diagnosis and treatment in New Zealand

Endometriosis is a chronically painful, invasive, inflammatory disease, with limited treatment options and long delays to diagnosis, which impacts 10% of females in New Zealand.

Introduction

As part of a larger group discussion study, this paper covers three themes associated with endometriosis patient experiences: intensity of pain, diagnostic tool shortcomings and perspectives of treatment options.

Materials and methods

The goal of this research was the inclusion of patient voices to guide research priorities. In early 2022, 50 New Zealand endometriosis patients participated in anonymous, asynchronous, text-based group discussions on the VisionsLive platform. The patients ranged in age from 18-48. The patients answered 50 questions, 23 text-based and 27 quantitative, and then took part in online group discussions.

Results and discussion

The average age of symptom onset was 15.3 years, while the average delay from symptom onset to a working or surgically confirmed diagnosis was 7.91 years. The top five reported symptoms within the cohort were pain-based, and the participants discussed the many impacts of this pain on their work and education. The four main diagnostic tools employed on this cohort were abdominal ultrasound (72%), transvaginal ultrasound (68%), laparoscopy (82%) and sharing their symptom history with a medical practitioner (88%). The most common emotions patients experienced following receiving a diagnosis of endometriosis were relief (86%), feeling overwhelmed (54%), and anger (32%). The main treatments offered to this cohort were pain relief (96%), laparoscopic surgery (84%) and the combined oral contraceptive pill (80%). Of these three treatments, only laparoscopic surgery was viewed positively by the majority of users, with 67% considering laparoscopy an effective treatment, compared to 46% of users for pain relief, and 25% of users for the combined oral contraceptive pill.

Conclusions

Gathering the voice of patients revealed that long delays to diagnosis and dismissal by medical practitioners frequently manifests as a reaction of relief by patients once diagnosed. Results also showed treatment options such as pain relief and hormonal medications were often considered ineffective, but were routinely offered as the first, or only, options for patients. It is therefore important that both quicker routes to diagnosis and more effective treatment options be developed.

Influence of the gut microbiota on endometriosis: Potential role of chenodeoxycholic acid and its derivatives

The gut microbiota (GM) has received extensive attention in recent years, and its key role in the establishment and maintenance of health and in the development of diseases has been confirmed. A strong correlation between the GM and the progression of endometriosis (EMS) has been observed in emerging research. Alterations in the composition and function of the GM have been described in many studies on EMS. In contrast, the GM in the environment of EMS, especially the GM metabolites, such as bile acids and short-chain fatty acids that are related to the pathogenesis of EMS, can promote disease progression. Chenodeoxycholic acid (CDCA), as one of the primary bile acids produced in the liver, is metabolized by various enzymes derived from the GM and is critically important in maintaining intestinal homeostasis and regulating lipid and carbohydrate metabolism and innate immunity. Given that the complexity of CDCA as a signalling molecule and the interaction between the GM and EMS have not been clarified, the role of the CDCA and GM in EMS should be understood from a novel perspective. However, few articles on the relationship between CDCA and EMS have been reviewed. Therefore, we review the available and possible potential links between CDCA, the GM and EMS and put forward the hypothesis that CDCA and its derivative obeticholic acid can improve the symptoms of EMS through the GM.

Targeting Oxidative Stress Involved in Endometriosis and Its Pain

Endometriosis is a common gynecological disorder seen in women and is characterized by chronic pelvic pain and infertility. This disorder is becoming more prevalent with increased morbidity. The etiology of endometriosis remains to be fully elucidated, which will lead to improved therapeutic options. In this review, we will evaluate the biochemical mechanisms leading to oxidative stress and their implication in the pathophysiology of endometriosis, as well as potential treatments that target these processes. A comprehensive exploration of previous research revealed that endometriosis is associated with elevated reactive oxygen species and oxidation products, decreased antioxidants and detoxification enzymes, and dysregulated iron metabolism. High levels of oxidative stress contributed to inflammation, extracellular matrix degradation, angiogenesis, and cell proliferation, which may explain its role in endometriosis. Endometriosis-associated pain was attributed to neurogenic inflammation and a feed-forward mechanism involving macrophages, pro-inflammatory cytokines, and pain-inducing prostaglandins. N-acetylcysteine, curcumin, melatonin, and combined vitamin C and E supplementation displayed promising results for the treatment of endometriosis, but further research is needed for their use in this population.

The Gut Microbiota: A Double Edge Sword in Endometriosis

Endometriosis that afflicts 1 in 10 women of reproductive age is characterized by growth of endometrial tissue in the extra-uterine sites and encompasses metabolic-, immunologic- and endocrine-disruption. Importantly, several comorbidities are associated with endometriosis, especially autoimmune disorders such as inflammatory bowel disease. Primarily thought of as a condition arising from retrograde menstruation, emerging evidence uncovered a functional link between the gut microbiota and endometriosis. Specifically, recent findings revealed altered gut microbiota profiles in endometriosis and in turn this altered microbiota appears to be causal in the disease progression, implying a bi-directional crosstalk. In this review, we discuss the complex etiology and pathogenesis of endometriosis emphasizing on this recently recognized role of gut microbiome. We review the gut microbiome structure and functions and its complex network of interactions with the host for maintenance of homeostasis that is crucial for disease prevention. We highlight the underlying mechanisms on how some bacteria promotes disease progression and others protects against endometriosis. Further, we highlight the areas that require future emphases in the gut microbiome-endometriosis nexus and the potential microbiome-based therapies for amelioration of endometriosis.

Endometriosis Is Undervalued: A Call to Action

Endometriosis is an inflammatory chronic pain condition caused by uterine tissue growing outside of the uterus that afflicts at least 11% of women (and people assigned female at birth) worldwide. This condition results in a substantial burden to these women, and society at large. Although endometriosis was first identified over 160 years ago, substantial knowledge gaps remain, including confirmation of the disease's etiology. Research funding for endometriosis is limited, with funding from bodies like the National Institutes of Health (NIH) constituting only 0.038% of the 2022 health budget—for a condition that affects 6.5 million women in the US alone and over 190 million worldwide. A major issue is that diagnosis of endometriosis is frequently delayed because surgery is required to histologically confirm the diagnosis. This delay increases symptom intensity, the risk of central and peripheral sensitization and the costs of the disease for the patient and their nation. Current conservative treatments of presumed endometriosis are pain management and birth control. Both of these methods are flawed and can be entirely ineffective for the reduction of patient suffering or improving ability to work, and neither addresses the severe infertility issues or higher risk of certain cancers. Endometriosis research deserves the funding and attention that befits a disease with its substantial prevalence, effects, and economic costs. This funding could improve patient outcomes by introducing less invasive and more timely methods for diagnosis and treatment, including options such as novel biomarkers, nanomedicine, and microbiome alterations.