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

Lactobacilli-Mediated Regulation of the Microbial-Immune Axis: A Review of Key Mechanisms, Influencing Factors, and Application Prospects

Lactobacilli, as the main member of food microorganisms, is an important component of the intestinal microbial community and plays crucial roles in regulating the immune capacity of the body. This review provides a comprehensive exploration of the key components of Lactobacilli-mediated immune regulation effects, including the immunogenic components (peptidoglycan and lipoteichoic acid) and metabolites (short-chain fatty acids, bacteriocins, and exopolysaccharides), which can interact with host immune cell receptors to initiate complex immune signaling pathways. In addition, the immunomodulatory activity can be influenced by multiple factors including species differences, host-related factors (age, physiological conditions, and gut microbiota), and environmental factors (nutrient substrates, temperatures, etc.), and the application strategies including precision probiotic development, gene-editing driven engineering, and nanocarrier systems have also been proposed to enhance the immunomodulatory potential. Finally, this review provides the theoretical basis for microbial intervention in immune-related diseases and offers prospects for applications in the food and pharmaceutical industries.

Could a Mediterranean Diet Modulate Alzheimer's Disease Progression? The Role of Gut Microbiota and Metabolite Signatures in Neurodegeneration

Neurodegenerative disorders such as Alzheimer's disease (AD), the most common form of dementia, represent a growing global health crisis, yet current treatment strategies remain primarily palliative. Recent studies have shown that neurodegeneration through complex interactions within the gut-brain axis largely depends on the gut microbiota and its metabolites. This review explores the intricate molecular mechanisms linking gut microbiota dysbiosis to cognitive decline, emphasizing the impact of microbial metabolites, including short-chain fatty acids (SCFAs), bile acids, and tryptophan metabolites, on neuroinflammation, blood-brain barrier (BBB) integrity, and amyloid-β and tau pathology. The paper highlights major microbiome signatures associated with Alzheimer's disease, detailing their metabolic pathways and inflammatory crosstalk. Dietary interventions have shown promise in modulating gut microbiota composition, potentially mitigating neurodegenerative processes. This review critically examines the influence of dietary patterns, such as the Mediterranean and Western diets, on microbiota-mediated neuroprotection. Bioactive compounds like prebiotics, omega-3 fatty acids, and polyphenols exhibit neuroprotective effects by modulating gut microbiota and reducing neuroinflammation. Furthermore, it discusses emerging microbiome-based therapeutic strategies, including probiotics, prebiotics, postbiotics, and fecal microbiota transplantation (FMT), as potential interventions for slowing Alzheimer's progression. Despite these advances, several knowledge gaps remain, including interindividual variability in microbiome responses to dietary interventions and the need for large-scale, longitudinal studies. The study proposes an integrative, precision medicine approach, incorporating microbiome science into Alzheimer's treatment paradigms. Ultimately, cognizance of the gut-brain axis at a mechanistic level could unlock novel therapeutic avenues, offering a non-invasive, diet-based strategy for managing neurodegeneration and improving cognitive health.

Broadening horizons: microbiota as a novel biomarker and potential treatment for endometriosis

As a heterogeneous disease, endometriosis is associated with diagnostic delay. Delayed diagnosis, physical discomfort, hormone therapy, and inconvenience in daily life and work all contribute to a decreased quality of life for endometriosis patients. Early clinical diagnosis is highly important for the intervention and treatment of endometriosis. Currently, reliable non-invasive diagnostic methods are lacking, and laparoscopic examination combined with pathological diagnosis is considered the "gold standard" for definitively diagnosing endometriosis. An increasing number of studies have confirmed the correlation between endometriosis and microbial ecological changes. Microbial dysbiosis is an important factor in the development and progression of endometriosis. Certain key microbial species and their metabolites can induce functional alterations in endometrial cells through various mechanisms, often preceding the emergence of clinical symptoms. Endometriosis are chronic inflammatory diseases, with an immunoinflammatory response as the pathological foundation. The microbiome may participate in the pathological mechanisms of endometriosis through multiple pathways, including mediating inflammatory responses, regulating immune responses, participating in estrogen regulation, interfering with metabolic activities, and modulating the gut-brain axis. Therefore, the microbiome holds potential as an early non-invasive diagnostic and therapeutic target for endometriosis patients. This study summarizes and analyses the correlations between microorganisms and their metabolites and the onset of endometriosis, aiming to provide novel insights into the etiology, diagnosis, and treatment of endometriosis.

Dietary index for gut microbiota and its inverse association with female infertility: evidence from NHANES 2013-2018

Background

Infertility has become a global health concern, especially as the aging population continues to grow. Previous studies suggest that gut microbiota plays a crucial role in female reproductive health. This study aimed to investigate the association between the Dietary Index for Gut Microbiota (DI-GM) and female infertility.

Methods

We analyzed data from 8,910 participants aged 20-45 years in the NHANES 2013-2018 cycles. DI-GM scores were calculated based on dietary recall interviews, including 14 foods and nutrients associated with gut health. Female infertility was identified through reproductive health questionnaires. Weighted logistic regression models were used to assess the relationship between DI-GM and infertility, with adjustments for demographic, lifestyle, and health-related covariates. Restricted cubic spline (RCS) analyses explored non-linear associations, and subgroup analyses ensured the robustness of the results.

Results

A significant negative association was observed between DI-GM and female infertility (adjusted OR = 0.89, 95% CI: 0.83-0.95, p < 0.001). Participants with DI-GM scores ≥6 had a 40% lower risk of infertility compared to those with scores 0-3 (OR = 0.60, 95% CI: 0.44-0.82, p = 0.001). RCS analyses revealed an L-shaped non-linear relationship, with a threshold at DI-GM = 5. Subgroup analyses indicated stronger associations in women with lower education levels and those with coronary heart disease (P for interaction <0.05).

Conclusion

Our findings demonstrate that a higher DI-GM score is associated with a reduced risk of female infertility, suggesting that dietary interventions targeting gut microbiota may offer a cost-effective strategy for improving reproductive health. Further longitudinal and interventional studies are warranted to confirm causality and elucidate underlying mechanisms.

Associations of Dietary Index for Gut Microbiota and Flavonoid Intake With Female Infertility in the United States

This study aimed to investigate the associations between a dietary index for gut microbiota (DI-GM), flavonoid intake, and female infertility, while exploring age-specific differences in these relationships to identify potential dietary strategies for female infertility prevention. This cross-sectional study focused on female participants aged 18-45 years, with data obtained from the 2017-2018 cycle of the National Health and Nutrition Examination Survey (NHANES). Weighted multivariable logistic regression models were employed to examine the associations between DI-GM, flavonoid intake, and self-reported female infertility. Age-stratified analyses were performed to evaluate whether these associations varied across reproductive life stages. Higher DI-GM scores were significantly associated with reduced infertility risk (aOR = 0.30, 95% CI: 0.13-0.71, p = 0.006), with the strongest protective effects observed in women aged < 35 years (Q3: aOR = 0.13, 95% CI: 0.03-0.58, p = 0.007; Q4: aOR = 0.27, 95% CI: 0.09-0.77, p = 0.015). Beneficial gut microbiota scores also showed a protective effect (aOR = 0.75, 95% CI: 0.57-0.98, p = 0.036). Among women aged ≥ 35 years, moderate flavonoid intake (Q2) showed a significant inverse association with female infertility risk (aOR = 0.19, 95% CI: 0.06-0.66, p = 0.009). Our findings reveal novel evidence that higher DI-GM scores and moderate flavonoid intake are significantly linked to a lower risk of female infertility, with age-specific patterns observed. Higher DI-GM scores showed significant protective effects in younger women (< 35 years), while moderate flavonoid intake was protective in women aged ≥ 35 years. These findings underscore the potential of personalized dietary strategies targeting gut microbiota composition and flavonoid intake as cost-effective approaches for female infertility prevention and management across different reproductive life stages.

Integrated microbiome and metabolomics analysis reveals the alleviating effect of Pediococcus acidilactici on colitis

Colitis is a complicated disease caused by multiple factors, seriously threatening the host health and the development of animal husbandry. Probiotics have been demonstrate to participate in the active regulation of multiple gastrointestinal disease, gut microbiota and metabolism, but research on the efficacy of Pediococcus acidilactici isolated from dogs in alleviating colitis remains scarce. Here, we aimed to investigate the ameliorative effects of Pediococcus acidilactici isolated from dogs on colitis induced by LPS and its underlying molecular mechanisms. For this purpose, we collected colon contents from 15 mice for amplicon sequencing and metabolic analysis. Results showed that Pediococcus acidilactici could relieve the colon damage and cytokine disorder caused by colitis. Microbiome analysis showed that colitis could cause a significant decrease in the gut microbial diversity and abundance, but Pediococcus acidilactici administration could restore the microbial index to the control level. Metabolomics analysis showed that 8 metabolic pathways and 5 (spermine, L-Arginine, 15-Deoxy-Delta12,14-PGJ2, prostaglandin J2, and 15(S)-HETE) metabolites may be involved in the alleviation of colitis by Pediococcus acidilactici. In summary, these findings demonstrated that the positive regulation effect of Pediococcus acidilactici on gut microbiota and metabolism may be one of its underlying mechanisms to alleviate colitis. Additionally, this study also conveyed a vital message that Pediococcus acidilactici isolated from dogs may serve as a promising candidate to ameliorate Pediococcus acidilactici.

Unveiling the Mechanisms of Pain in Endometriosis: Comprehensive Analysis of Inflammatory Sensitization and Therapeutic Potential

Endometriosis is a complicated, estrogen-dependent gynecological condition with a high morbidity rate. Pain, as the most common clinical symptom of endometriosis, severely affects women's physical and mental health and exacerbates socioeconomic burden. However, the specific mechanisms behind the occurrence of endometriosis-related pain remain unclear. It is currently believed that the occurrence of endometriosis pain is related to various factors, such as immune abnormalities, endocrine disorders, the brain-gut axis, angiogenesis, and mechanical stimulation. These factors induce systemic chronic inflammation, which stimulates the nerves and subsequently alters neural plasticity, leading to nociceptive sensitization and thereby causing chronic pain. In this paper, we compile and review the articles published on the study of nociceptive sensitization and endometriosis pain mechanisms. Starting from the factors influencing the chronic pain associated with endometriosis, we explain the relationship between these factors and chronic inflammation and further elaborate on the potential mechanisms by which chronic inflammation induces nociceptive sensitization. We aim to reveal the possible mechanisms of endometriosis pain, as well as nociceptive sensitization, and offer potential new targets for the treatment of endometriosis pain.

A disturbed communication between hypothalamic-pituitary-ovary axis and gut microbiota in female infertility: is diet to blame?

Female infertility is a multifactorial condition influenced by various genetic, environmental, and lifestyle factors. Recent research has investigated the significant impact of gut microbiome dysbiosis on systemic inflammation, metabolic dysfunction, and hormonal imbalances, which can potentially impair fertility. The gut-brain axis, a bidirectional communication system between the gut and the brain, also plays a significant role in regulating reproductive functions. Emerging evidence suggests that the gut microbiome can influence brain functions and behavior, further emphasizing the importance of the microbiota-gut-brain axis in reproduction. Given their role as a major modulator of the gut microbiome, diet and dietary factors, including dietary patterns and nutrient intake, have been implicated in the development and management of female infertility. Hence, this review aims to highlight the impact of dietary patterns, such as the Western diet (WD) and Mediterranean diet (MD), and to decipher their modulatory action on the microbiota-gut-brain axis in infertile women. By contrasting the detrimental effects of WD with the therapeutic potential of MD, we emphasize the pivotal role of a balanced diet rich in nutrients in promoting a healthy gut microbiome. These insights underscore the potential of targeted dietary interventions and lifestyle modifications as promising strategies to enhance reproductive outcomes in subfertile women.

Butyrate as a Potential Modulator in Gynecological Disease Progression

This review investigates the therapeutic potential of butyrate, a short-chain fatty acid (SCFA) produced by gut microbiota, in the prevention and treatment of various gynecological diseases, including polycystic ovary syndrome (PCOS), endometriosis, and gynecologic cancers like cervical and ovarian cancer. These conditions often pose treatment challenges, with conventional therapies offering limited and temporary relief, significant side effects, and a risk of recurrence. Emerging evidence highlights butyrate's unique biological activities, particularly its role as a histone deacetylase (HDAC) inhibitor, which allows it to modulate gene expression, immune responses, and inflammation. In PCOS, butyrate aids in restoring hormonal balance, enhancing insulin sensitivity, and reducing chronic inflammation. For endometriosis, butyrate appears to suppress immune dysregulation and minimize lesion proliferation. Additionally, in cervical and ovarian cancers, butyrate demonstrates anticancer effects through mechanisms such as cell cycle arrest, apoptosis induction, and suppression of tumor progression. Dietary interventions, particularly high-fiber and Mediterranean diets, that increase butyrate production are proposed as complementary approaches, supporting natural microbiota modulation to enhance therapeutic outcomes. However, butyrate's short half-life limits its clinical application, spurring interest in butyrate analogs and probiotics to maintain stable levels and extend its benefits. This review consolidates current findings on butyrate's multifaceted impact across gynecological health, highlighting the potential for microbiota-centered therapies in advancing treatment strategies and improving women's reproductive health.