The microbiome in autoimmune diseases

Limosilactobacillus reuteri - a probiotic gut commensal with contextual impact on immunity

The gut microbiome plays a key role in human health, influencing various biological processes and disease outcomes. The historical roots of probiotics are traced back to Nobel Laureate Élie Metchnikoff, who linked the longevity of Bulgarian villagers to their consumption of sour milk fermented by Lactobacilli. His pioneering work led to the global recognition of probiotics as beneficial supplements, now a multibillion-dollar industry. Modern probiotics have been extensively studied for their immunomodulatory effects. Limosilactobacillus reuteri (L. reuteri), a widely used probiotic, has garnered significant attention for its systemic immune-regulatory properties, particularly in relation to autoimmunity and cancer. This review delves into the role of L. reuteri in modulating immune responses, with a focus on its impact on systemic diseases.

The biological and sociological implications of diversity, equity, and inclusion (DEI): life within microbiomes and on earth

From a biological point of view, Diversity, Equity, and Inclusion (DEI) are important at multiple levels, which include our genetics, microbiomes, diets, and all organ system interactions. Considering only DEI's sociological aspects is equivalent to the error of "throwing out the baby with the bath water." Variances in microbial diversity within our microbiomes might affect our health through systemic interactions affecting metabolites, maintaining immune homeostasis, and wound healing of cellular damage from an infection, physical stress, or psychological trauma. An imbalance of our immune cell subsets, both innate and adaptive, and the microbes in any of our microbiomes might lead to more cellular damage from excessive inflammation and oxidative stress and less immune regulation. The immune dysregulation may occur due to the loss of endometrial barriers enabling the spread of microbes, environmental pollutants, and allergens. Heat waves, sleep deprivation, and increased prevalence of pollutants such as polychlorinated biphenyls, which weaken endothelial barriers, may be responsible for the enhanced prevalence of physical and psychological stresses. Leakage of our useful gut microbiota into the periphery might initiate inflammatory responses, and an altered gut microbiome might affect the gut-brain axis that influences physical and mental health.

Human microbiota in dengue infection: A narrative review

Dengue fever, a widespread mosquito-borne viral infection in tropical regions, typically manifests fever and gastrointestinal symptoms, including nausea, vomiting, and diarrhea. However, the human gut microbiota's role in dengue pathogenesis remains incompletely understood. Studies have demonstrated dysbiosis during dengue virus infection, characterized by increased abundance of potentially pathogenic bacteria like Bacteroidaceae and Proteobacteria, particularly during the critical phase. Furthermore, microbial translocation and leaky gut syndrome, characterized by the translocation of intestinal microbial products, have been observed in dengue patients and are associated with hypercytokinemia, plasma leakage, and disease severity. These findings underscore the necessity for an in-depth investigation into the role of human intestinal microbiota as a potential contributing factor in the pathogenesis and progression of dengue. Further research focusing on human intestinal microbiota, leaky gut syndrome, and the potential implications of treatment with oral bacteriotherapy, as previously observed in other viral diseases, is essential to clarify dengue pathology and evaluate new therapeutic strategies.

Differences in the Fecal Metabolome of Autoimmune Pancreatitis Patients

BACKGROUND

Chronic pancreatitis is a risk factor for pancreatic cancer. Autoimmune pancreatitis is a unique form of chronic pancreatitis that is primarily characterized by its immune mediate etiology, clinically resembling pancreatic cancer, yet uniquely responsive to steroid treatment.

OBJECTIVE

Early and accurate diagnosis of autoimmune pancreatitis is vital for effective treatment and patient prognosis, for which new diagnostic tools are urgently required. Gut microbiota dysbiosis has been identified to correlate with the development of pancreatic diseases, which provides new opportunities for the discovery of disease biomarkers.

METHODS

We utilized a mass spectrometric global metabolomics investigation of patient autoimmune pancreatitis and chronic pancreatitis fecal samples, investigating microbiome, dietary and human metabolism.

RESULTS

We discovered a series of newly identified metabolic signatures between both patient groups including enterolactone, 4-guanidinobutanoic acid, and methylthioadenosine sulfoxide. Additionally, the analysis revealed significant differences in several metabolic pathways such as fatty acids, alkaloids, amino acids and peptides.

CONCLUSION

Our observations provide novel insights into important metabolic human pathways and microbiome-derived metabolites to distinguish autoimmune pancreatitis from chronic pancreatitis. These findings reveal systemic metabolic responses and the identified metabolites may be developed into potential biomarkers for future diagnosis to distinguish between autoimmune pancreatitis and chronic pancreatitis.

Probiotic Interventions in Systemic Sclerosis Patients: A Systematic Review and Future Prospects

Background and Aims

Systemic sclerosis (SSc) is an uncommon autoimmune connective tissue disease distinguished by fibrosis and vascular abnormalities, often leading to gastrointestinal problems. This review explores the potential of probiotics in managing SSc-related gastrointestinal issues and modulating immune responses, highlighting the need for innovative treatments to improve patient well-being.

Methods

We performed an extensive literature search up to October 2023 in databases, including Web of Science, PubMed/MEDLINE, and Scopus.

Result

This review detected four articles that investigated the impact of probiotics on SSc. These studies, comprising non-randomized observational studies and randomized clinical trials, provide preliminary insights suggesting that probiotics may be efficacious in modulating the immune response and, consequently, in improving gastrointestinal symptoms in SSc patients.

Conclusion

The comprehensive review suggests that probiotics may aid in managing gastrointestinal symptoms and modulating immune responses in SSc. However, it is essential to acknowledge the limited existing evidence, underscoring the need for more rigorous randomized controlled trials to thoroughly assess their effectiveness.

Microbiome alterations in primary Sjögren's syndrome: Regional dysbiosis and microbiome-targeted therapeutic strategies

Primary Sjögren's syndrome (pSS) is a complex autoimmune disease characterized by diverse clinical manifestations. While xerophthalmia and xerostomia are hallmark symptoms, the disease often involves multiple organ systems, including the kidneys, lungs, nervous system, and gastrointestinal tract, leading to systemic morbidity in severe cases. Despite extensive research, the precise pathogenesis of pSS remains unclear, likely involving infectious, hormonal, and genetic factors. Emerging evidence highlights the microbiome as a key contributor to autoimmune diseases, including pSS. Dysbiosis in the oral, ocular, gut, and genital microbiomes plays a critical role in disease onset, progression, and variability. This review summarizes current findings on microbiome alterations in pSS, emphasizing their role in pathogenesis and clinical features, and explores microbiome-targeted therapies. Understanding the role of the microbiome in pSS pathophysiology could advance disease management and inspire targeted therapeutic strategies.

The intersection of microbiome and autoimmunity in long COVID-19: Current insights and future directions

Long COVID-19 affects a significant percentage of patients and is characterized by a wide range of symptoms, including weariness and mental fog as well as emotional symptoms like worry and sadness. COVID-19 is closely linked to the autoimmune disorders that are becoming more prevalent worldwide and are linked to immune system hyperactivation, neutrophil extracellular trap (NET) development, and molecular mimicry pathways. Long-term COVID-related autoimmune responses include a watchful immune system referring to the ability of immune system to constantly monitor the body for signs of infection, disease, or abnormal cells; altered innate and adaptive immune cells, autoantigens secreted by living or dead neutrophils, and high concentrations of autoantibodies directed against different proteins. The microbiome, which consists of billions of bacteria living in the human body, is essential for controlling immune responses and supporting overall health. The microbiome can affect the course of long COVID-associated autoimmunity, including the degree of illness, the rate of recovery, and the onset of autoimmune reactions. Although the precise role of the microbiome in long COVID autoimmunity is still being investigated, new studies indicate that probiotics, prebiotics, and dietary changes-interventions that target the microbiome-may be able to reduce autoimmune reactions and enhance long-term outcomes for COVID-19 survivors. More research is required to precisely understand how the microbiome affects COVID-19-related autoimmunity and to create tailored treatment plans.

Methyltransferase-like 3-mediated RNA N6-methyladenosine contributes to immune dysregulation: diagnostic biomarker and therapeutic target

Methyltransferase-like 3 (METTL3) plays a crucial role in post-transcriptional gene regulation. Substantial evidence links METTL3 to various immune dysfunctions, such as the suppression of antiviral immunity during viral infections and the disruption of immune tolerance in conditions like autoimmune diseases, myeloid leukemia, skin cancers, and anticancer immunotherapy. However, a thorough review and analysis of this evidence is currently missing, which limits the understanding of METTL3's mechanisms and significance in immune dysfunctions. This review aims to elucidate the roles and mechanisms of METTL3 in these immune issues, highlighting its connections and proposing new insights into its modulation of immune responses. Analysis results in this review suggest that METTL3 hampers antiviral immunity, worsens viral replication and infection, and disrupts immune tolerance; conversely, regulating METTL3 enhances antiviral immunity and facilitates viral clearance. Moreover, clinical data corroborates these findings, showing that METTL3 overexpression is associated with increased susceptibility to viral infections and autoimmune conditions. This review establishes a theoretical basis for considering METTL3 as a novel regulator, an important diagnostic biomarker, and a potential target for treating immune dysfunctions.

A Mendelian randomization study to reveal gut-disc axis: causal associations between gut microbiota with intervertebral disc diseases

PURPOSE

Emerging evidence suggests a link between gut microbiota and intervertebral disc diseases (IDDs); however, the causal relationships remain unclear. This study aimed to evaluate the causal effects of gut microbiota on the risk of cervical disc disorders (CDD), other intervertebral disc disorders (OIDD), pyogenic intervertebral disc infections, and discitis, shedding light on the potential "gut-disc axis".

METHODS

Genetic variation data for 202 gut microbiota taxa were obtained from the Dutch Microbiome Project, and disease outcome data were sourced from the FinnGen consortium. A Mendelian Randomization (MR) approach was employed to assess causal relationships, using genetic variants as instrumental variables. Sensitivity analyses, including tests for pleiotropy, heterogeneity, and reverse causation, ensured robust findings.

RESULTS

The study identified 20 gut microbial taxa with significant associations to IDDs. Notably, taxa within the Erysipelotrichaceae family showed consistent protective effects against OIDD after Bonferroni correction (P < 0.05). Associations between several species and specific diseases, such as Alistipes senegalensis with CDD and Ruminococcus lactaris with discitis, were also observed. Sensitivity analyses confirmed no evidence of confounding or reverse causation.

CONCLUSION

This study provides evidence of causal relationships between specific gut microbiota and IDDs, supporting the existence of a "gut-disc axis." The findings suggest that microbial dysbiosis may influence spinal health through systemic inflammation and immune regulation. These insights open new possibilities for microbiota-targeted interventions, such as probiotics or dietary modifications, to prevent or manage IDDs. However, further research is required to validate these therapeutic strategies.

Children who develop celiac disease are predicted to exhibit distinct metabolic pathways among their gut microbiota years before diagnosis

Celiac disease (CD) is an autoimmune disease caused by a loss of gluten tolerance in genetically predisposed individuals. While 30%-40% of people possess the predisposing alleles, only 1%-2% are diagnosed with CD, suggesting that environmental factors are involved in disease pathogenesis. To determine an association between pediatric CD and the gut microbiome, we analyzed fecal samples from a prospective cohort study (ABIS). These samples were collected from children who later developed CD (CD progressors) and age-matched healthy children (at ages 1, 2.5, and 5) with similar HLA genotypes, breastfeeding durations, and gluten exposure times. We previously reported gut microbiome differences at ages 2.5 and 5 in this cohort; here, we present findings from samples collected at age 1 (n = 5). We identified 14 ASVs differing significantly between CD progressors and controls, including taxa linked to CD pathogenesis. CD progressors had increased Firmicutes and higher alpha diversity in IgA- bacteria. Using PICRUSt, we analyzed metabolic pathways enriched in CD progressors compared to controls at ages 1, 2.5, and 5 (n = 5-16), revealing enriched inflammatory and pathogenic pathways potentially contributing to CD-related immune dysregulation. While results are based on the primary EdgeR analysis, we also applied a non-parametric method of statistical analysis, reporting those results with supplementary figures. In conclusion, our findings suggest distinct metabolic pathways enriched in the gut microbiome of CD progressors years before diagnosis, which could inform targeted therapeutics for CD. As discussed in the limitations section, this small pilot study should be replicated with larger sample sizes for broader generalization.

IMPORTANCE

We analyzed gut microbiome data from children who later developed celiac disease (CD progressors) compared to healthy children in the first 5 years of life. Using fecal samples corresponding to the three phases of gut microbiome development, we uncovered enriched functional microbial pathways in CD progressors at age 1. Some of these pathways, implicated in bacterial pathogenesis, microbiota modulation, and inflammation, have been correlated with CD. We also identified taxa in CD progressors at age 1 including Lachnospiraceae, Alistipes, and Bifidobacterium dentium that were previously associated with CD. These findings suggest a potential role for these taxa and enriched pathways in pediatric CD onset years before diagnosis, highlighting potential for early interventions. While the findings of this exploratory study should be validated with larger sample sizes, our study suggests microbial metabolic pathways related to CD onset, enhancing our understanding of CD pathogenesis and the role of gut microbiome-mediated early alterations.

Innate Immunity in Helicobacter pylori Infection and Gastric Oncogenesis

Helicobacter pylori is an extremely common cause of gastritis that can lead to gastric adenocarcinoma over time. Approximately half of the world's population is infected with H. pylori, making gastric cancer the fourth leading cause of cancer-related deaths worldwide. Innate immunity significantly contributes to systemic and local immune responses, maintains homeostasis, and serves as the vital link to adaptive immunity, and in doing so, mediates H. pylori infection outcomes and consequent cancer risk and development. The gastric innate immune system, composed of gastric epithelial and myeloid cells, is uniquely challenged by its need to interact simultaneously and precisely with commensal microbiota, exogenous pathogens, ingested substances, and endogenous exfoliated cells. Additionally, innate immunity can be detrimental by promoting chronic infection and fibrosis, creating an environment conducive to tumor development. This review summarizes and discusses the complex role of innate immunity in H. pylori infection and subsequent gastric oncogenesis, and in doing so, provides insights into how these pathways can be exploited to improve prevention and treatment.

Exploring antigenic variation in autoimmune endocrinopathy

Autoimmune disorders develop owing to a misdirected immune response against self-antigen. Genetic studies have revealed that numerous variants in genes encoding immune system proteins are associated with the development of autoimmunity. Indeed, many of these genetic variants in key immune receptors or transcription factors are common in the pathogenesis of several different autoimmune conditions. In contrast, the proclivity to develop autoimmunity to any specific target organ or tissue is under-researched. This has particular relevance to autoimmune endocrine conditions, where organ-specific involvement is the rule. Genetic polymorphisms in the genes encoding the targets of autoimmune responses have been shown to be associated with predisposition to several autoimmune diseases, including type 1 diabetes, autoimmune thyroid disease and Addison's disease. Mechanistically, variations leading to decreased intrathymic expression, overexpression, different localisation, alternative splicing or post-translational modifications can interfere in the tolerance induction process. This review will summarise the different ways genetic variations in certain genes encoding endocrine-specific antigens (INS, TSHR, TPO, CYP21A2, PIT-1) may predispose to different autoimmune endocrine conditions.

Behavioral alterations in antibiotic-treated mice associated with gut microbiota dysbiosis: insights from 16S rRNA and metabolomics

The gut and brain interact through various metabolic and signaling pathways, each of which influences mental health. Gut dysbiosis caused by antibiotics is a well-known phenomenon that has serious implications for gut microbiota-brain interactions. Although antibiotics disrupt the gut microbiota's fundamental structure, the mechanisms that modulate the response and their impact on brain function are still unclear. It is imperative to comprehend and investigate crucial regulators and factors that play important roles. We aimed to study the effect of long-term antibiotic-induced disruption of gut microbiota, host metabolomes, and brain function and, particularly, to determine the basic interactions between them by treating the C57BL/6 mice with two different, most commonly used antibiotics, ciprofloxacin and amoxicillin. Anxiety-like behavior was confirmed by the elevated plus-maze test and open field test. Gut microbes and their metabolite profiles in fecal, serum, and brain samples were determined by 16S rRNA sequencing and untargeted metabolomics. In our study, long-term antibiotic treatment exerted anxiety-like effects. The fecal microbiota and metabolite status revealed that the top five genera found were Lactobacillus, Bacteroides, Akkermansia, Ruminococcus_gnavus_group, and unclassified norank_f_Muribaculaceae. The concentration of serotonin, L-Tyrosine, 5-Hydroxy-L-tryptophan, L-Glutamic acid, L-Glutamate, 5-Hydroxyindole acetic acid, and dopaminergic synapsis was comparatively low, while adenosine was high in antibiotic-treated mice. The KEGG enrichment analysis of serum and brain samples showed that amino acid metabolism pathways, such as tryptophan metabolism, threonine metabolism, serotonergic synapsis, methionine metabolism, and neuroactive ligand-receptor interaction, were significantly decreased in antibiotic-treated mice. Our study demonstrates that long-term antibiotic use induces gut dysbiosis and alters metabolic responses, leading to the dysregulation of brain signaling molecules and anxiety-like behavior. These findings highlight the complex interactions between gut microbiota and metabolic functions, providing new insights into the influence of microbial communities on gut-brain communication.

Microbial dynamics of acute pancreatitis: integrating culture, sequencing, and bile impact on bacterial populations and gaseous metabolites

Background

Our study examined the composition of the intestinal microflora in a hospitalized patient with AP symptoms treated several months earlier for diverticulitis. The therapeutic intervention necessitated Hartmann's procedure, culminating in colostomy creation.

Aims

Employing a thorough microbiological analysis we attempted to demonstrate whether the microflora isolated from the peripancreatic fluid exhibited a stronger correlation with the contents of the stoma or with the rectal swab. Additionally, we sought to determine the association between later onset of AP and diverticulitis.

Methods

Following clinical materials from the patient in the initial phase of AP were collected: rectal swab, colostomy bag contents (in the publication referred to as stoma content/stool) and peripancreatic fluid. Microbiological analysis was performed, including classic culture methodology, NGS techniques, and genotyping methodologies. Furthermore, the effect of bile on the shift in the population of selected bacterial species was examined.

Results

The NGS technique confirmed greater consistency in bacteria percentage (phyla/family) between stoma content and peripancreatic fluid. In both samples, a clear dominance of the Proteobacteria phyla (over 75%) and the Enterobacteriaceae family was demonstrated. Moreover, NGS verified the presence of the Fusobacteriota phylum and Fusobacteriaceae family only in rectal swabs, which may indicate a link between this type of bacteria and the etiology of diverticulitis. We observed that Escherichia coli 33 isolated from stool exhibited active gaseous metabolite production (mainly hydrogen).

Conclusions

The abundant production of hydrogen may substantially impact enzymatic processes, inducing specific alterations in disulfide bonds and trypsin inactivation. Our investigation alludes to the conceivable active involvement of bile in effecting qualitative and quantitative modifications in the peripancreatic microbiota composition, establishing a correlation between released bile and bacterial generation of gaseous metabolites.

Oral microbiota shifts following tooth loss affect gut health

BACKGROUND

Tooth loss not only impairs oral function but also affects gut health by altering the host microbiota. Understanding the oral-gut axis can provide insights into systemic health implications following tooth loss.

METHODS

Using an animal model, we extracted the molars of C57 mice. Saliva and fecal samples were collected for 16S rRNA and metagenomic sequencing to analyze changes in the oral and gut microbiota. Pearson correlation analysis assessed the relationship between altered microbial communities.

RESULTS

The study found a significant reduction in oral microbiota diversity following tooth loss, with increased Proteobacteria and decreased Muribacter. Gut microbiota showed increased Firmicutes and decreased Bacteroidota. Correlations between oral and gut microbiota changes were observed, indicating a potential link between tooth loss and alterations in intestinal microbial balance.

CONCLUSION

In the mouse model, tooth loss disrupted the balance of the oral-gut microbiota, with potential implications for intestinal health. Although these findings are from a murine model, considering the existence of the oral-gut axis balance in the human body, it is reasonable to postulate that following tooth loss in humans, the health of the intestinal microecology may also warrant attention.

Gut microbiota and their metabolites in the immune response of rheumatoid arthritis: Therapeutic potential and future directions

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by persistent joint inflammation, damage, and loss of function. In recent years, the role of gut microbiota and its metabolites in immune regulation has attracted increasing attention. The gut microbiota influences the host immune system's homeostasis through various mechanisms, regulating the differentiation, function, and immune tolerance of immune cells. Dysbiosis of the gut microbiota in RA patients is closely associated with abnormal activation of immune cells and excessive secretion of inflammatory cytokines. Metabolites produced by the gut microbiota, such as short-chain fatty acids (SCFAs), tryptophan metabolites, bile acids, and amino acid metabolites, play a critical role in immune responses, regulating the functions of immune cells like T cells, B cells, and macrophages, and inhibiting the release of pro-inflammatory cytokines. Restoring the balance of the gut microbiota and optimizing the production of metabolic products may become a new strategy for RA treatment. This review discusses the role of gut microbiota and its metabolites in the immune response of RA, exploring how they influence the immunopathological process of RA through the regulation of immune cells and key immune factors. It also provides a theoretical basis for future therapeutic strategies based on gut microbiota modulation.

Fecal microbiota transplant from long-living Ames dwarf mice alters the microbial composition and biomarkers of liver health in normal mice

Aging is associated with intestinal dysbiosis, a condition characterized by diminished microbial biodiversity and inflammation. This leads to increased vulnerability to extraintestinal manifestations such as autoimmune, metabolic, and neurodegenerative conditions thereby accelerating mortality. As such, modulation of the gut microbiome is a promising way to extend healthspan. In this study, we explore the effects of fecal microbiota transplant (FMT) from long-living Ames dwarf donors to their normal littermates, and vice versa, on the recipient gut microbiota and liver transcriptome. Importantly, our previous studies highlight differences between the microbiome of Ames dwarf mice relative to their normal siblings, potentially contributing to their extended lifespan and remarkable healthspan. Our findings demonstrate that FMT from Ames dwarf mice to normal mice significantly alters the recipient's gut microbiota, potentially reprogramming bacterial functions related to healthy aging, and changes the liver transcriptome, indicating improved metabolic health. Particularly, the microbiome of Ames dwarf mice, characterized by a higher abundance of beneficial bacterial families such as Peptococcaceae, Oscillospiraceae, and Lachnospiraceae, appears to play a crucial role in modulating these effects. Alongside, our mRNA sequencing and RT-PCR validation reveals that FMT may contribute to the significant downregulation of p21, Elovl3, and Insig2, genes involved with cellular senescence and liver metabolic pathways. Our data suggest a regulatory axis exists between the gut and liver, highlighting the potential of microbiome-targeted therapies in promoting healthy aging. Future research should focus on functional validation of altered microbial communities and explore the underlying biomolecular pathways that confer geroprotection.

Evaluation of the recovery effects of antibiotic-resistant Lactiplantibacillus plantarum subsp. plantarum ATCC14917 on the antibiotic-disturbed intestinal microbiota using a mice model

AIMS

Supplementing Lactobacillus alongside antibiotic treatment was a curative strategy to modulate gut microbiota and alleviate antibiotic-associated dysbiosis. But the lactobacilli that are used as probiotics are sensitive or have a low level of resistance to antibiotics, so they usually cannot achieve their beneficial effect, since they are killed by the applied antibiotics. This work aimed to develop the highly resistant Lactiplantibacillus plantarum subsp. plantarum ATCC14917 to cephalexin and evaluate its recovery effects of antibiotic-resistant L. plantarum on the antibiotic-disturbed intestinal microbiota using a mice model.

METHODS AND RESULTS

After successive growth in lactic acid bacteria susceptibility medium broth containing a gradually increasing concentration of cephalexin for 70 days, the minimum inhibitory concentration (MIC) of L. plantarum ATCC14917 to cephalexin significantly increased from 16 to 8192 μg ml-1, but stabilized at 4096 μg ml-1. After sequencing and sequence analysis, no mutated genes were detected on mobile elements, showing that horizontal transfer of mutated genes could not occur. Compared to the control group (Con), feeding mice with cephalexin (1 mg ml-1; Cep) led to a decrease in alpha diversity. However, concurrently used cephalexin and L. plantarum (Cep + LpR) increased the alpha diversity in both microbial richness and diversity. The Cep + LpR group showed a lower distance with the Con group than either Cep or Cep + LpS groups, suggesting that resistant L. plantarum treatment was more effective than the original strain for the recovery of intestinal microbiota. Compared to the cephalexin-treated group, concurrent ingestion of cephalexin together with resistant L. plantarum significantly increased the proportion of beneficial bacteria and decreased Firmicutes/Bacteroidetes ratio and abundance of potential pathogens.

CONCLUSIONS

The use of antibiotic-resistant L. plantarum ATCC14917 contributed to a much faster and richer recovery of the gut microbiota disturbed by antibiotic treatment compared to the original strain.

Hallmarks of aging: A user's guide for comparative biologists

Since the first description of a set of characteristics of aging as so-called hallmarks or pillars in 2013/2014, these characteristics have served as guideposts for the research in aging biology. They have been examined in a range of contexts, across tissues, in response to disease conditions or environmental factors, and served as a benchmark for various anti-aging interventions. While the hallmarks of aging were intended to capture generalizable characteristics of aging, they are derived mostly from studies of rodents and humans. Comparative studies of aging including species from across the animal tree of life have great promise to reveal new insights into the mechanistic foundations of aging, as there is a great diversity in lifespan and age-associated physiological changes. However, it is unclear how well the defined hallmarks of aging apply across diverse species. Here, we review each of the twelve hallmarks of aging defined by Lopez-Otin in 2023 with respect to the availability of data from diverse species. We evaluate the current methods used to assess these hallmarks for their potential to be adapted for comparative studies. Not unexpectedly, we find that the data supporting the described hallmarks of aging are restricted mostly to humans and a few model systems and that no data are available for many animal clades. Similarly, not all hallmarks can be easily assessed in diverse species. However, for at least half of the hallmarks, there are methods available today that can be employed to fill this gap in knowledge, suggesting that these studies can be prioritized while methods are developed for comparative study of the remaining hallmarks.

Mechanisms Associated With Renal Injury in Hyperuricemia and Strategies for the Development of Natural Active Substances

Hyperuricemia (HUA) is a metabolic condition resulting from an abnormality in the process of purine metabolism. Its occurrence has been on the rise globally. The results of relevant studies show that 5% to 12% of HUA patients will eventually develop gout, and one-third of these patients may involve the kidneys and develop kidney disease. Although the severe renal health hazards associated with excessive uric acid levels are well known, the specific molecular mechanisms remain unknown. Therefore, this paper provides insights into the mechanisms and related chain reactions of HUA leading to renal injury from three perspectives: imbalance of intestinal homeostasis, oxidative stress response, and NLRP3 inflammasome. In addition, standing against the background of the strong side effects and high tolerability disadvantages of commercially available uric acid-lowering drugs such as allopurinol, benzbromarone, and febuxostat, the development of a new active anti-hyperuricemic drug with fewer side effects is justified. This article reviews the progress of research on natural actives (probiotics, dietary polyphenols, peptides) with a high safety profile, multi-targeting, and integrative modulatory effects, in an attempt to provide some ideas for drug developers.

Linking dietary fiber to human malady through cumulative profiling of microbiota disturbance

Dietary fiber influences the composition and metabolic activity of microbial communities, impacting disease development. Current understanding of the intricate fiber-microbe-disease tripartite relationship remains fragmented and elusive, urging a systematic investigation. Here, we focused on microbiota disturbance as a robust index to mitigate various confounding factors and developed the Bio-taxonomic Hierarchy Weighted Aggregation (BHWA) algorithm to integrate multi-taxonomy microbiota disturbance data, thereby illuminating the complex relationships among dietary fiber, microbiota, and disease. By leveraging microbiota disturbance similarities, we (1) classified 32 types of dietary fibers into six functional subgroups, revealing correlations with fiber solubility; (2) established associations among 161 diseases, uncovering shared microbiota disturbance patterns that explain disease co-occurrence (e.g., type II diabetes and kidney diseases) and distinct microbiota patterns that discern symptomatically similar diseases (e.g., inflammatory bowel disease and irritable bowel syndrome); (3) designed a body-site-specific microbiota disturbance scoring scheme, computing a disturbance score (DS) for each disease and highlighting the pronounced capacity of Crohn's disease to disturb gut microbiota (DS = 14.01) in contrast with food allergy's minimal capacity (DS = 0.74); (4) identified 1659 fiber-disease associations, predicting the potential of dietary fiber to modulate specific microbiota changes associated with diseases of interest; (5) established murine models of inflammatory bowel disease to validate the preventive and therapeutic effects of arabinoxylan that notably perturbed the Bacteroidetes and Firmicutes phyla, as well as the Bacteroidetes and Lactobacillus genera, aligning with our model predictions. To enhance data accessibility and facilitate targeted dietary intervention development, we launched an interactive webtool-mDiFiBank at https://mdifibank.org.cn/.

Effects of the Curcuminoid and Non-Curcuminoid Compounds of Turmeric on the Gut Microbiome and Inflammation: Potential Use in the Treatment and Prevention of Disease

The gut microbiome is a complex system that directly interacts with and influences many systems in the body. This delicate balance of microbiota plays an important role in health and disease and is highly influenced by lifestyle factors and the surrounding environment. As further research emerges, understanding the full potential of the gut microbiome and the impact of using nutraceuticals to positively influence its function may open the door to greater therapeutic outcomes in the treatment and prevention of disease. Curcumin, a bioactive compound derived from the turmeric rhizome, has been studied in depth for its influence on human health as a potent anti-inflammatory and antioxidant properties. However, the therapeutic activity of curcumin is limited by its low oral bioavailability. While most available research has primarily focused on the curcuminoid compounds of turmeric, the non-curcuminoid compounds hold promise to offer therapeutic benefits while synergistically enhancing the bioavailability of curcumin and supporting the gut microbiome. This review summarizes current knowledge of the relationship between the gut and the various systems within the body, and how dysbiosis, or disruption in the gut microbial balance, leads to inflammation and increased risk of chronic disease. The review also summarizes recent research that focuses on the bioactivity of both the curcuminoid and non-curcuminoid compounds that comprise the whole turmeric root and their synergistic role in enhancing bioavailability to support a healthy gut microbiome and promising use in the treatment and prevention of disease.

Revisiting the cancer microbiome using PRISM

Recent controversy around the cancer microbiome highlights the need for improved microbial analysis methods for human genomics data. We developed PRISM, a computational approach for precise microorganism identification and decontamination from low-biomass sequencing data. PRISM removes spurious signals and achieves excellent performance when benchmarked on a curated dataset of 62,006 known true- and false-positive taxa. We then use PRISM to detect microbes in 8 cancer types from the CPTAC and TCGA datasets. We identify rich microbiomes in gastrointestinal tract tumors in CPTAC and identify bacteria in a subset of pancreatic tumors that are associated with altered glycoproteomes, more extensive smoking histories, and higher tumor recurrence risk. We find relatively sparse microbes in other cancer types and in TCGA, which we demonstrate may reflect differing sequencing parameters. Overall, PRISM does not replace gold-standard controls, but it enables higher-confidence analyses and reveals tumor-associated microorganisms with potential molecular and clinical significance.

Oxygenation and intestinal perfusion and its association with perturbations of the early life gut microbiota composition of children with congenital heart disease

Background

Early life gut microbiota is known to shape the immune system and has a crucial role in immune homeostasis. Only little is known about composition and dynamics of the intestinal microbiota in infants with congenital heart disease (CHD) and potential influencing factors.

Methods

We evaluated the intestinal microbial composition of neonates with CHD (n = 13) compared to healthy controls (HC, n = 30). Fecal samples were analyzed by shotgun metagenomics. Different approaches of statistical modeling were applied to assess the impact of influencing factors on variation in species composition. Unsupervised hierarchical clustering of the microbial composition of neonates with CHD was used to detect associations of distinct clusters with intestinal tissue oxygenation and perfusion parameters, obtained by the "oxygen to see" (O2C) method.

Results

Overall, neonates with CHD showed an intestinal core microbiota dominated by the genera Enterococcus (27%) and Staphylococcus (20%). Furthermore, a lower abundance of the genera Bacteroides (8% vs. 14%), Parabacteroides (1% vs. 3%), Bifidobacterium (4% vs. 12%), and Escherichia (8% vs. 23%) was observed in CHD compared to HCs. CHD patients that were born by vaginal delivery showed a lower fraction of the genera Bacteroides (15% vs. 21%) and Bifidobacterium (7% vs. 22%) compared to HCs and in those born by cesarean section, these genera were not found at all. In infants with CHD, we found a significant impact of oxygen saturation (SpO2) on relative abundances of the intestinal core microbiota by multivariate analysis of variance (F[8,2] = 24.9, p = 0.04). Statistical modeling suggested a large proportional shift from a microbiota dominated by the genus Streptococcus (50%) in conditions with low SpO2 towards the genus Enterococcus (61%) in conditions with high SpO2. We identified three distinct compositional microbial clusters, corresponding neonates differed significantly in intestinal blood flow and global gut perfusion.

Conclusion

Early life differences in gut microbiota of CHD neonates versus HCs are possibly linked to oxygen levels. Delivery method may affect microbiota stability. However, further studies are needed to assess the effect of potential interventions including probiotics or fecal transplants on early life microbiota perturbations in neonates with CHD.

Elimination of oral foci of infection might lead to clinical improvement of Graves' orbitopathy

PURPOSE

Graves' disease (GD) and Graves' orbitopathy (GO) are multifactorial disorders with links to the gut microbiome and autoimmunity. It is observed that patients with GD exhibit altered gut microbiome diversity. However, little is known about the role of oral microbiota in GD and GO. This study aims to investigate the impact of oral health and oral sanitation on the clinical course of GO in patients disqualified from glucocorticoid treatment due to oral infections.

METHODS

We reviewed 188 admissions of 127 patients with GO, hospitalized in a tertiary university hospital. Clinical, biochemical, imaging, ophthalmological, and oral health assessment data from each admission were analyzed. Patients excluded from the glucocorticoids (GCs) therapy due to oral foci of infection had the clinical activity score (CAS) reassessed after three months, and they were divided into two groups: with and without improvement.

RESULTS

Finishing dental treatment in the meantime was the only factor significantly correlated with improvement in these patients (p = 0.041). The secondary finding was that anti-thyroid peroxidase antibodies titer was significantly higher in the group with oral foci of infection considered as a contraindication for GCs (medians 28.50 vs 128.00; p = 0.026), and those patients were more likely to smoke than the group without oral issues (p = 0.024).

CONCLUSIONS

The results of our study suggest that monitoring and treating oral diseases may be pertinent in patients with GO and might serve as a supportive treatment strategy for managing the condition.

KEY MESSAGES

What is known: There is a recognized link between gut dysbiosis and the autoimmune processes in Graves' Disease (GD) and Graves' Orbitopathy (GO).

WHAT IS NEW

Elevated levels of TPOAb have been observed in patients with GO who also have oral foci of infection. Dental treatment has been shown to lead to significant clinical improvements in patients with GO. Maintaining oral hygiene might serve as a supportive treatment strategy for managing GO.

Lupus and inflammatory bowel disease share a common set of microbiome features distinct from other autoimmune disorders

OBJECTIVES

This study aims to elucidate the microbial signatures associated with autoimmune diseases, particularly systemic lupus erythematosus (SLE) and inflammatory bowel disease (IBD), compared with colorectal cancer (CRC), to identify unique biomarkers and shared microbial mechanisms that could inform specific treatment protocols.

METHODS

We analysed metagenomic datasets from patient cohorts with six autoimmune conditions-SLE, IBD, multiple sclerosis, myasthenia gravis, Graves' disease and ankylosing spondylitis-contrasting these with CRC metagenomes to delineate disease-specific microbial profiles. The study focused on identifying predictive biomarkers from species profiles and functional genes, integrating protein-protein interaction analyses to explore effector-like proteins and their targets in key signalling pathways.

RESULTS

Distinct microbial signatures were identified across autoimmune disorders, with notable overlaps between SLE and IBD, suggesting shared microbial underpinnings. Significant predictive biomarkers highlighted the diverse microbial influences across these conditions. Protein-protein interaction analyses revealed interactions targeting glucocorticoid signalling, antigen presentation and interleukin-12 signalling pathways, offering insights into possible common disease mechanisms. Experimental validation confirmed interactions between the host protein glucocorticoid receptor (NR3C1) and specific gut bacteria-derived proteins, which may have therapeutic implications for inflammatory disorders like SLE and IBD.

CONCLUSIONS

Our findings underscore the gut microbiome's critical role in autoimmune diseases, offering insights into shared and distinct microbial signatures. The study highlights the potential importance of microbial biomarkers in understanding disease mechanisms and guiding treatment strategies, paving the way for novel therapeutic approaches based on microbial profiles.

TRIAL REGISTRATION NUMBER

NCT02394964.

Adult-Onset Still's Disease (AOSD) in Patient with Previous Lyme Disease

Adult-onset Still's Disease (AOSD) is a rare autoimmune disorder causing systemic inflammation that presents with a rash, fever, polyarthritis, and a characteristic serum hyperferritinemia. There is a complex relationship between infections and autoimmune disease, however, the association of AOSD with lyme disease is not well established. Here we present a case of AOSD in a 29-year-old male with a recent history of lyme disease. After ruling out infection and malignancy, a diagnosis of AOSD was made. From this report, we aim to raise more awareness for AOSD and recommend providers consider this diagnosis as a potential sequela of lyme disease.

HFD aggravated the arthritis and atherosclerosis by altering the intestinal status and gut microbiota

Rheumatoid arthritis (RA) and cardiovascular disease (CVD) are both the chronic inflammatory disease. To investigate the influence of secondary atherosclerosis on arthritis mice, we treated the ApoE-/- mice with K/BxN serum and high fat diet (HFD), and subsequently assessed the phenotypes as well as immune profiles of K/BxN serum and HFD induced ApoE-/- mice. We found that HFD treatment aggravated the hyperlipidemia, atherosclerotic lesions, ankle swelling and arthropathy of mice. We further demonstrated that HFD altered the gut microbiota and metabolism, intestinal homeostasis and Th17/Treg cell balance in lamina propria lymphocytes. Moreover, HFD decreased the number of Peyer' s patches and altered the expression profiling of gut immune cells. In addition, HFD increased the number of aortic leukocytes and macrophages, then aggravated the atherosclerosis in aorta, which led to greater inflammation in mice aorta and aortic root. Collectively, our study indicated that HFD aggravated the arthritis and atherosclerosis, which may be contributed by microbiota dysbiosis, the intestinal permeability and disrupted immunological homeostasis.

Capsule robots for the monitoring, diagnosis, and treatment of intestinal diseases

Current evidence suggests that the intestine as the new frontier for human health directly impacts both our physical and mental health. Therefore, it is highly desirable to develop the intelligent tool for the enhanced diagnosis and treatment of intestinal diseases. During the past 20 years, capsule robots have opened new avenues for research and clinical applications, potentially revolutionizing human health monitor, disease diagnosis and treatment. In this review, we summarize the research progress of edible multifunctional capsule robots in intestinal diseases. To begin, we introduce the correlation between the intestinal microbiome, intestinal gas and human diseases. After that, we focus on the technical structure of edible multifunctional robots. Subsequently, the biomedical applications in the monitoring, diagnosis and treatment of intestinal diseases are discussed in detail. Last but not least, the main challenges of multifunctional capsule robots during the development process are summarized, followed by a vision for future development opportunities.

Mechanism of action of Nrf2 and its related natural regulators in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovitis that can lead to joint deformities. To date, more than 18 million individuals worldwide have been diagnosed with RA, making it one of the most prevalent autoimmune diseases globally and posing a significant threat to public health and safety. Due to the complex pathogenesis of the disease, which involves autoimmunity, genetics, inflammation and oxidative stress in the body's tissues, the current drug therapy generally targets a single molecule, and effective and efficient drugs involving multiple levels and targets are lacking; thus, there is an urgent need for high-quality research and treatment in this field. Nuclear transcription factor erythroid 2-associated factor 2 (Nrf2) plays a crucial role in cellular resistance to oxidative stress and electrophilic attacks and is a potential pharmacological target for chronic disease treatment. While currently no drugs that target Nrf2 have been approved specifically for RA treatment, such an approach holds great significance. In recent years, the use of natural products to treat RA and other chronic conditions has become increasingly widespread because of their superior efficacy and minimal side effects. Therefore, this article provides a review of the mechanism of Nrf2 in RA and summarizes natural products that target Nrf2 and its associated pathways in the treatment of RA, aiming to offer new insights and strategies for the prevention and management of RA.

Evaluation of Periodontitis and Fusobacterium nucleatum Among Colorectal Cancer Patients: An Observational Cross-Sectional Study

BACKGROUND

Periodontitis has been associated with an increased risk of CRC, as well as a worse prognosis due to increased inflammation mediators and carcinogenic factors. Moreover, direct and indirect virulence factors from periodontal pathogens, such as Fusobacterium nucleatum, could play a pivotal role in malignant transformation and progression. This cross-sectional study aims to evaluate the presence and the stage of periodontitis in a cohort of patients with CRC. The secondary aim is to assess the presence of F. nucleatum and its relationship with patients' general characteristics, concomitant pathologies, tumor characteristics, and drug therapy.

MATERIALS AND METHODS

Patients affected by CRC underwent dental examination and periodontal charting with the "North Carolina" probe to assess the presence and stage of periodontitis, according to the new classification of periodontal diseases of the World Workshop of the European Federation of Periodontology (EFP) and the American Academy of Periodontology (AAP) 2017. F. nucleatum presence was assessed by a dorsal tongue swab and related to the patient's general characteristics, concomitant pathologies, tumor characteristics, and drug therapy.

RESULTS

Periodontal disease was found in 94.3% of I/II CRC stage patients and 100% of III/IV CRC stage patients. Severe periodontitis was found in 76% of the advanced CRC stage and 87.9% of patients with initial CRC, while initial periodontitis was found in 12.1% of initial CRC and 24% of late CRC stages, respectively, without significant differences. F. nucleatum presence showed no correlation between the patient's and tumor's characteristics, comorbidities, and drug assumed.

CONCLUSIONS

Periodontal disease showed a high prevalence among CRC patients. Moreover, severe periodontitis has a higher prevalence in CRC patients compared to initial periodontitis. F. nucleatum presence was unrelated to CRC stage, site, other comorbidities, and drug therapies. With these data, it is not possible to admit a direct relationship between CRC and periodontal disease, but further case-control studies must be carried out to further prove this aspect. Preventive and operative targeted strategies to maintain a healthy oral status are suggested in CRC patients.

Gut microbiota and autoimmune diseases: Insights from Mendelian randomization

In recent years, the scientific community has shown interest in the role of gut microbiota in the development of autoimmune diseases (AID). Although observational studies have revealed significant associations between gut microbiota and AID like rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis, these connections do not necessarily imply causality. Mendelian randomization (MR) approach has been extensively employed to investigate the causal relationship. Relevant MR study findings indicate that a reduction in beneficial microbial populations, particularly Bifidobacterium and Lactobacillus, and an increase in potential pathogenic microbes, is correlated with an elevated AID risk. Given the innovative potential of MR in unraveling the etiopathogenesis of AIDs, this article offers an overview of this methodological approach and its recent applications in AID research.

Lupus and other autoimmune diseases: Epidemiology in the population of African ancestry and diagnostic and management challenges in Africa

Autoimmune diseases are prevalent among people of African ancestry living outside Africa. However, the burden of autoimmune diseases in Africa is not well understood. This article provides a global overview of the current burden of autoimmune diseases in individuals of African descent. It also discusses the major factors contributing to autoimmune diseases in this population group, as well as the challenges involved in diagnosing and managing autoimmune diseases in Africa.

The microbiome shapes immunity in a sex-specific manner in mouse models of Alzheimer's disease

INTRODUCTION : Preclinical studies reveal that the microbiome broadly affects immune responses and deposition and/or clearance of amyloid-beta (Aβ) in mouse models of Alzheimer's disease (AD). Whether the microbiome shapes central and peripheral immune profiles in AD models remains unknown. METHODS : We examined adaptive immune responses in two mouse models containing AD- related genetic predispositions (3xTg and 5xFAD) in the presence or absence of the microbiome. RESULTS : T and B cells were altered in brain-associated and systemic immune tissues between genetic models and wildtype mice, with earlier signs of immune activity in females. Systemic immune responses were modulated by the microbiome and differed by sex. Further, the absence of a microbiome in germ-free mice resulted in reduced cognitive deficits, primarily in females. DISCUSSION : These data reveal sexual dimorphism in early signs of immune activity and microbiome effects, and highlight an interesting interaction between sex and the microbiome in mouse models of AD.

Impact of cooperative or competitive dynamics between the yeast Saccharomyces cerevisiae and lactobacilli on the immune response of the host

Fungi and bacteria can be found coexisting in a wide variety of environments. The combination of their physical and molecular interactions can result in a broad range of outcomes for each partner, from competition to cooperative relationships. Most of these interactions can also be found in the human gastrointestinal tract. The gut microbiota is essential for humans, helping the assimilation of food components as well as the prevention of pathogen invasions through host immune system modulation and the production of beneficial metabolites such as short-chain fatty acids (SCFAs). Several factors, including changes in diet habits due to the progressive Westernization of the lifestyle, are linked to the onset of dysbiosis statuses that impair the correct balance of the gut environment. It is therefore crucial to explore the interactions between commensal and diet-derived microorganisms and their influence on host health. Investigating these interactions through co-cultures between human- and fermented food-derived lactobacilli and yeasts led us to understand how the strains' growth yield and their metabolic products rely on the nature and concentration of the species involved, producing either cooperative or competitive dynamics. Moreover, single cultures of yeasts and lactobacilli proved to be ideal candidates for developing immune-enhancing products, given their ability to induce trained immunity in blood-derived human monocytes in vitro. Conversely, co-cultures as well as mixtures of yeasts and lactobacilli have been shown to induce an anti-inflammatory response on the same immune cells in terms of cytokine profiles and activation surface markers, opening new possibilities in the design of probiotic and dietary therapies.

A population-scale analysis of 36 gut microbiome studies reveals universal species signatures for common diseases

The gut microbiome has been implicated in various human diseases, though findings across studies have shown considerable variability. In this study, we reanalyzed 6314 publicly available fecal metagenomes from 36 case-control studies on different diseases to investigate microbial diversity and disease-shared signatures. Using a unified analysis pipeline, we observed reduced microbial diversity in many diseases, while some exhibited increased diversity. Significant alterations in microbial communities were detected across most diseases. A meta-analysis identified 277 disease-associated gut species, including numerous opportunistic pathogens enriched in patients and a depletion of beneficial microbes. A random forest classifier based on these signatures achieved high accuracy in distinguishing diseased individuals from controls (AUC = 0.776) and high-risk patients from controls (AUC = 0.825), and it also performed well in external cohorts. These results offer insights into the gut microbiome's role in common diseases in the Chinese population and will guide personalized disease management strategies.

Alterations of the microbiome across body sites in systemic lupus erythematosus: A systematic review and meta-analysis

BACKGROUND

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with unclear etiology. Growing evidence suggests the microbiome plays a role in SLE pathogenesis. However, findings are inconsistent across studies due to factors like small sample sizes and geographical variations. A comprehensive meta-analysis is needed to elucidate microbiome alterations in SLE.

OBJECTIVE

This study aimed to provide a systematic overview of microbiota dysbiosis across body sites in SLE through a meta-analysis of alpha diversity indices, beta diversity indices, and abundance taxa of microbiome.

METHODS

A literature search was conducted across four databases to identify relevant studies comparing SLE patients and healthy controls. Extracted data encompassed alpha and beta diversity metrics, as well as bacterial, fungal, and viral abundance across gut, oral, skin, and other microbiota. Study quality was assessed using the Newcastle-Ottawa Scale. Standardized mean differences and pooled effect sizes were calculated through meta-analytical methods.

RESULTS

The analysis showed reduced alpha diversity and distinct beta diversity in SLE, particularly in the gut microbiota. Taxonomic analysis revealed compositional variations in bacteria from the gut and oral cavity. However, results for fungi, viruses, and bacteria from other sites were inconsistent due to limited studies.

CONCLUSIONS

This meta-analysis offers a comprehensive perspective on microbiome dysbiosis in SLE patients across diverse body sites and taxa. The observed variations underscore the microbiome's potential role in SLE pathogenesis. Future research should address geographical variations, employ longitudinal designs, and integrate multi-omics approaches.

Effects of probiotics supplementation in gastrointestinal complications and quality of life of patients with systemic sclerosis: A systematic review

Background

Systemic sclerosis (SSc), as an autoimmune rheumatic disease characterized by immune dysregulation and vasculopathy, affects multiple organs. Due to the high burden of its symptoms on the health care system, this study aims to investigate the effects of probiotic supplements in patients with SSc.

Methods

We searched electronic databases with predefined search terms in PubMed, Scopus, and ISI Web of Science up to June 2023. Randomized controlled trials that evaluated the effects of probiotic supplementation in adult patients suffering from SSc were included in the study. Results of the included studies were reported as weighted mean difference (WMD) with a 95 % confidence interval (CI).

Results

Four studies met the inclusion criteria and were included in the meta-analysis. There was a total of 176 SSc patients. The results show a significant effect of probiotics supplementation on gastrointestinal (GI) symptoms containing reflux (WMD: -0.36, 95 % CI: -0.51 to -0.22, p-value <0.001), gas and bloating (WMD: -0.88, 95 % CI: -1.05 to -0.7, p-value<0.001). However, the results for constipation (WMD: -0.12, 95 % CI: -0.27 to 0.04, p-value = 0.13), diarrhea (WMD: -0.14, 95 % CI: -0.31 to 0.03, p-value = 0.10), and fecal incontinence (WMD: 0.04, 95 % CI: -0.06 to 0.15, p-value = 0.43) were insignificant.

Conclusion

Supplementing with probiotics may alleviate a few numbers of GI complications in SSc. Nevertheless, due to the limited number of studies, more well-designed studies are needed to strengthen these results.

Primary biliary cholangitis has causal effects on systemic rheumatic diseases: a Mendelian randomization study

BACKGROUND

An association has been observed between primary biliary cholangitis (PBC) and systemic rheumatic diseases (SRDs) in observational studies, however the exact causal link remains unclear. We aimed to evaluate the causal effects of PBC on SRDs through Mendelian randomization (MR) analysis.

METHODS

The genome-wide association study (GWAS) summary data were obtained from MRC IEU OpenGWAS and FinnGen databases. Independent genetic variants for PBC were selected as instrumental variables. Inverse variance weighted was used as the main approach to evaluate the causal effects of PBC on Sjögren syndrome (SS), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), mixed connective tissue disease (MCTD) and polymyositis (PM). Horizontal pleiotropy and heterogeneity were measured by MR‒Egger intercept test and Cochran's Q value, respectively.

RESULTS

PBC had causal effects on SS (OR = 1.177, P = 8.02e-09), RA (OR = 1.071, P = 9.80e-04), SLE (OR = 1.447, P = 1.04e-09), SSc (OR = 1.399, P = 2.52e-04), MCTD (OR = 1.306, P = 4.92e-14), and PM (OR = 1.416, P = 1.16e-04). Based on the MR‒Egger intercept tests, horizontal pleiotropy was absent (all P values > 0.05). The robustness of our results was further enhanced by the leave-one-out method.

CONCLUSIONS

Our research has provided new insights into PBC and SRDs, indicating casual effects on various SRDs.

Causal relationships between gut microbiome and obstructive sleep apnea: a bi-directional Mendelian randomization

Background

Previous studies have identified a clinical association between gut microbiota and Obstructive sleep apnea (OSA), but the potential causal relationship between the two has not been determined. Therefore, we aim to utilize Mendelian randomization (MR) to investigate the potential causal effects of gut microbiota on OSA and the impact of OSA on altering the composition of gut microbiota.

Methods

Bi-directional MR and replicated validation were utilized. Summary-level genetic data of gut microbiota were derived from the MiBioGen consortium and the Dutch Microbiome Project (DMP). Summary statistics of OSA were drawn from FinnGen Consortium and Million Veteran Program (MVP). Inverse-variance-weighted (IVW), weighted median, MR-Egger, Simple Mode, and Weighted Mode methods were used to evaluate the potential causal link between gut microbiota and OSA.

Results

We identified potential causal associations between 23 gut microbiota and OSA. Among them, genus Eubacterium xylanophilum group (OR = 0.86; p = 0.00013), Bifidobacterium longum (OR = 0.90; p = 0.0090), Parabacteroides merdae (OR = 0.85; p = 0.00016) retained a strong negative association with OSA after the Bonferroni correction. Reverse MR analyses indicated that OSA was associated with 20 gut microbiota, among them, a strong inverse association between OSA and genus Anaerostipes (beta = -0.35; p = 0.00032) was identified after Bonferroni correction.

Conclusion

Our study implicates the potential bi-directional causal effects of the gut microbiota on OSA, potentially providing new insights into the prevention and treatment of OSA through specific gut microbiota.

Genetically predicted the causal relationship between gut microbiota and the risk of polymyositis/dermatomyositis: a Mendelian randomization analysis

Introduction

Observational studies suggest associations between gut microbiota and polymyositis (PM) and dermatomyositis (DM), but causal relationships are unclear. We investigate the causal effects of gut microbiota on PM and DM, providing insights hoping to provide insights for future treatment and prevention.

Methods

Summary statistics of gut microbiota were obtained from a multi-ethnic Genome Wide Association Studies (GWAS) meta-analysis, including 119 taxa from 18,340 Europeans. PM/DM statistics were extracted from GWAS analyses. Mendelian randomization (MR) with IVW, MR-Egger, and weighted median methods was performed. Sensitivity analyses addressed heterogeneity and pleiotropy. Of the 119 bacterial genera studied, six showed causal links.

Results

Alloprevotella (OR: 3.075, 95% CI: 1.127-8.386, p = 0.028), Ruminococcaceae UCG003 (OR: 4.219, 95% CI: 1.227-14.511, p = 0.022), Dialister (OR: 0.273, 95% CI: 0.077-0.974, p = 0.045) were associated with PM. Anaerotruncus (OR: 0.314, 95% CI: 0.112-0.882, p = 0.028), Ruminococcaceae UCG002 (OR: 2.439, 95% CI: 1.173-5.071, p = 0.017), Sutterella (OR: 3.392, 95% CI: 1.302-8.839, p = 0.012) were related to DM. Sensitivity analyses validated these associations.

Discussion

We establish causal relationships between Ruminococcaceae, Sutterella, Anaerotruncus with DM, Alloprevotella, Ruminococcaceae UCG003, and Dialister with PM. Common microbiota, like Ruminococcaceae, have significant clinical implications. These findings open up greater possibilities for the gut microbiota to contribute to the development of PM/DM and for future monitoring of the gut microbiota in patients with PM/DM.

A two sample mendelian randomization analysis investigates causal effects between gut microbiome and immune related Vasculitis

Observational data suggest a link between gut microbiota and immune-related vasculitis, but causality remains unclear. A bidirectional mendelian randomization study was conducted using public genome-wide data. The inverse-variance-weighted (IVW) method identified associations and addressed heterogeneity.Families Clostridiaceae 1 and Actinomycetaceae correlated positively with granulomatosis with polyangiitis risk, while classes Lentisphaeria and Melainabacteria, and families Lachnospiraceae and Streptococcaceae showed negative associations. Behçet's disease was positively associated with the risk of family Streptococcaceae abundance. And other several gut microbiota constituents were identified as potential risk factors for immune-related vasculitis. Furthermore, combining positive association results from the IVW analysis revealed numerous shared gut microbiota constituents associated with immune-related vasculitis. MR analysis demonstrated a causal association between the gut microbiota and immune-related vasculitis, offering valuable insights for subsequent mechanistic and clinical investigations into microbiota-mediated immune-related vasculitis.

Bibliometric and visualization analysis of the application of inorganic nanomaterials to autoimmune diseases

Objective: To conduct bibliometric analysis of the application of inorganic nanomaterials to autoimmune diseases to characterize current research trends and to visualize past and emerging trends in this field in the past 15 years. Methods: The evolution and thematic trends of the application of inorganic nanomaterials to autoimmune diseases from January 1, 1985, to March 15, 2024, were analyzed by bibliometric analysis of data retrieved and extracted from the Web of Science Core Collection (WoSCC) database. A total of 734 relevant reports in the literature were evaluated according to specific characteristics such as year of publication, journal, institution, country/region, references, and keywords. VOSviewer was used to build co-authorship analysis, co-occurrence analysis, co-citation analysis, and network visualization. Some important subtopics identified by bibliometric characterization are further discussed and reviewed. Result: From 2009 to 2024, annual publications worldwide increased from 11 to 95, an increase of 764%. ACS Nano published the most papers (14) with the most citations (1372). China (230 papers, 4922 citations) and the Chinese Academy of Sciences (36 papers, 718 citations) are the most productive and influential country and institution, respectively. The first 100 keywords were co-clustered to form four clusters: (1) the application of inorganic nanomaterials in drug delivery, (2) the application of inorganic nano-biosensing to autoimmune diseases, (3) the use of inorganic nanomaterials for imaging applied to autoimmune diseases, and (4) the application of inorganic nanomaterials in the treatment of autoimmune diseases. Combination therapy, microvesicles, photothermal therapy (PTT), targeting, diagnostics, transdermal, microneedling, silver nanoparticles, psoriasis, and inflammatory cytokines are the latest high-frequency keywords, marking the emerging frontier of inorganic nanomaterials in the field of autoimmune diseases. Sub-topics were further discussed to help researchers determine the scope of research topics and plan research directions. Conclusion: Over the past 39 years, the application of inorganic nanotechnology to the field of autoimmune diseases shows extensive cooperation between countries and institutions, showing a continuous increase in the number of reports in the literature, and has clinical translation prospects. Future research should further improve the safety of inorganic nanomaterials, clarify the mechanism of action of nanomaterials, establish a standardized nanomaterial preparation and performance evaluation system, and ultimately achieve the goal of early detection and precise treatment of autoimmune diseases.

Nature of the Association between Rheumatoid Arthritis and Cervical Cancer and Its Potential Therapeutic Implications

It is now established that patients with rheumatoid arthritis (RA) have an increased risk of developing cervical cancer (CC) or its precursor, cervical intraepithelial neoplasia (CIN). However, the underlying mechanisms of this association have not been elucidated. RA is characterized by unresolved chronic inflammation. It is suggested that human papillomavirus (HPV) infection in RA patients exacerbates inflammation, increasing the risk of CC. The tumor microenvironment in RA patients with CC is also marked by chronic inflammation, which aggravates the manifestations of both conditions. Gut and vaginal dysbiosis are also considered potential mechanisms that contribute to the chronic inflammation and aggravation of RA and CC manifestations. Numerous clinical and pre-clinical studies have demonstrated the beneficial effects of various nutritional approaches to attenuate chronic inflammation, including polyunsaturated fatty acids and their derivatives, specialized pro-resolving mediators (SPMs), probiotics, prebiotics, and certain diets. We believe that successful resolution of chronic inflammation and correction of dysbiosis, in combination with current anti-RA and anti-CC therapies, is a promising therapeutic approach for RA and CC. This approach could also reduce the risk of CC development in HPV-infected RA patients.

Intestinal Microbiota and Its Effect on Vaccine-Induced Immune Amplification and Tolerance

This review provides the potential of intestinal microbiota in vaccine design and application, exploring the current insights into the interplay between the intestinal microbiota and the immune system, with a focus on its intermediary function in vaccine efficacy. It summarizes families and genera of bacteria that are part of the intestinal microbiota that may enhance or diminish vaccine efficacy and discusses the foundational principles of vaccine sequence design and the application of gut microbial characteristics in vaccine development. Future research should further investigate the use of multi-omics technologies to elucidate the interactive mechanisms between intestinal microbiota and vaccine-induced immune responses, aiming to optimize and improve vaccine design.

Elucidating the Intricate Roles of Gut and Breast Microbiomes in Breast Cancer Metastasis to the Bone

BACKGROUND

Breast cancer is the most predominant and heterogeneous cancer in women. Moreover, breast cancer has a high prevalence to metastasize to distant organs, such as the brain, lungs, and bones. Patients with breast cancer metastasis to the bones have poor overall and relapse-free survival. Moreover, treatment using chemotherapy and immunotherapy is ineffective in preventing or reducing cancer metastasis.

RECENT FINDINGS

Microorganisms residing in the gut and breast, termed as the resident microbiome, have a significant influence on the formation and progression of breast cancer. Recent studies have identified some microorganisms that induce breast cancer metastasis to the bone. These organisms utilize multiple mechanisms, including induction of epithelial-mesenchymal transition, steroid hormone metabolism, immune modification, bone remodeling, and secretion of microbial products that alter tumor microenvironment, and enhance propensity of breast cancer cells to metastasize. However, their involvement makes these microorganisms suitable as novel therapeutic targets. Thus, studies are underway to prevent and reduce breast cancer metastasis to distant organs, including the bone, using chemotherapeutic or immunotherapeutic drugs, along with probiotics, antibiotics or fecal microbiota transplantation.

CONCLUSIONS

The present review describes association of gut and breast microbiomes with bone metastases. We have elaborated on the mechanisms utilized by breast and gut microbiomes that induce breast cancer metastasis, especially to the bone. The review also highlights the current treatment options that may target both the microbiomes for preventing or reducing breast cancer metastases. Finally, we have specified the necessity of maintaining a diverse gut microbiome to prevent dysbiosis, which otherwise may induce breast carcinogenesis and metastasis especially to the bone. The review may facilitate more detailed investigations of the causal associations between these microbiomes and bone metastases. Moreover, the potential treatment options described in the review may promote discussions and research on the modes to improve survival of patients with breast cancer by targeting the gut and breast microbiomes.

Probiotics and Paraprobiotics: Effects on Microbiota-Gut-Brain Axis and Their Consequent Potential in Neuropsychiatric Therapy

Neuropsychiatric disorders are clinical conditions that affect cognitive function and emotional stability, often resulting from damage or disease in the central nervous system (CNS). These disorders are a worldwide concern, impacting approximately 12.5% of the global population. The gut microbiota has been linked to neurological development and function, implicating its involvement in neuropsychiatric conditions. Due to their interaction with gut microbial communities, probiotics offer a natural alternative to traditional treatments such as therapeutic drugs and interventions for alleviating neuropsychiatric symptoms. Introduced by Metchnikoff in the early 1900s, probiotics are live microorganisms that provide various health benefits, including improved digestion, enhanced sleep quality, and reduced mental problems. However, concerns about their safety, particularly in immunocompromised patients, warrant further investigation; this has led to the concept of "paraprobiotics", inactivated forms of beneficial microorganisms that offer a safer alternative. This review begins by exploring different methods of inactivation, each targeting specific cellular components like DNA or proteins. The choice of inactivation method is crucial, as the health benefits may vary depending on the conditions employed for inactivation. The subsequent sections focus on the potential mechanisms of action and specific applications of probiotics and paraprobiotics in neuropsychiatric therapy. Probiotics and paraprobiotics interact with gut microbes, modulating the gut microbial composition and alleviating gut dysbiosis. The resulting neuropsychiatric benefits primarily stem from the gut-brain axis, a bidirectional communication channel involving various pathways discussed in the review. While further research is needed, probiotics and paraprobiotics are promising therapeutic agents for the management of neuropsychiatric disorders.

The relationship between dry eye disease and human microbiota: A review of the science

A complex relationship exists between human microbiota and the risk for ophthalmic disease. While the homeostatic composition of human microbiota is still being established, including what defines dysbiosis (i.e. changes in diversity and abundance), pilot research has begun to identify the potential influence of demographics, geography, and co-morbidities on the microbiota and describe their impact on ocular health. This review specifically focuses on the scientific relationships of the human oral and gut microbiota to dry eye disease (DED), a set of conditions impacting the tear film and ocular surface. Although data are sparse and often conflict across studies, the literature generally supports associations between microbial imbalance (dysbiosis) and DED and alterations in microbial diversity and abundance to specific aspects of DED. This review examines the relevant science and mechanistic relationships linking gut and oral dysbiosis and DED. Various physiochemical factors and therapeutic approaches that alter microbiota, including medications and fecal transplants are examined in relation to DED.

Intestinal barrier permeability: the influence of gut microbiota, nutrition, and exercise

The intestinal wall is a selectively permeable barrier between the content of the intestinal lumen and the internal environment of the body. Disturbances of intestinal wall permeability can potentially lead to unwanted activation of the enteric immune system due to excessive contact with gut microbiota and its components, and the development of endotoxemia, when the level of bacterial lipopolysaccharides increases in the blood, causing chronic low-intensity inflammation. In this review, the following aspects are covered: the structure of the intestinal wall barrier; the influence of the gut microbiota on the permeability of the intestinal wall via the regulation of functioning of tight junction proteins, synthesis/degradation of mucus and antioxidant effects; the molecular mechanisms of activation of the pro-inflammatory response caused by bacterial invasion through the TLR4-induced TIRAP/MyD88 and TRAM/TRIF signaling cascades; the influence of nutrition on intestinal permeability, and the influence of exercise with an emphasis on exercise-induced heat stress and hypoxia. Overall, this review provides some insight into how to prevent excessive intestinal barrier permeability and the associated inflammatory processes involved in many if not most pathologies. Some diets and physical exercise are supposed to be non-pharmacological approaches to maintain the integrity of intestinal barrier function and provide its efficient operation. However, at an early age, the increased intestinal permeability has a hormetic effect and contributes to the development of the immune system.

Metagenomic analysis revealed the association between gut microbiota and different ovary responses to controlled ovarian stimulation

The aim of this study was to assess the correlation between gut microbial taxonomy and various ovarian responses to controlled ovarian stimulation. A total of 22 IVF cycles with a follicle-to-oocyte index (FOI) < 0.5 and 25 IVF cycles with FOI ≥ 0.5 were included in this study. Baseline demographic characteristics were compared between the two groups. Metagenomic sequencing was performed to analyze fecal microbial community profiles. Mice were used to evaluate the effect of Bifidobacterium_longum on ovarian response to stimulation. Compared with FOI < 0.5 group, women in group with FOI ≥ 0.5 had significant more oocytes retrieved (p < 0.01). Prevotella_copri, Bateroides_vulgatus, Escherichia_coli and Bateroides_stercoris were more abundant in FOI < 0.5 group while Bifidobacterium_longum, Faecalibacterium_prausnitzii, Ruminococcus_gnavus and Bifidobacterium_pseudocatenula were more abundant in FOI ≥ 0.5 group. After adjusting for women's age and BMI, Pearson correlation analysis indicated alteration of gut microbiome was related with serum E2, FSH, number of oocytes retrieved and clinical pregnancy rate. Animal study showed ovarian response will be improved after Bifidobacterium_longum applied. An increased abundance of Bacteroidetes and Prevotella copri, as well as a decreased abundance of Bifidobacterium longum, have been found to be associated with poor ovarian responsiveness. Changes in gut microbiomes have been observed to be correlated with certain clinical characteristics. The potential enhancement of ovarian response may be facilitated by the integration of Bifidobacterium longum.