Gut microbiota diversity of hospitalized older adult patients with and without antibiotic-associated diarrhea

Function and therapeutic potential of Amuc_1100, an outer membrane protein of Akkermansia muciniphila: A review

The gut microbiota-derived protein Amuc_1100, a key outer membrane component of Akkermansia muciniphila, has emerged as a groundbreaking therapeutic agent with unique structural and functional properties. Amuc_1100 exerts multifaceted immune-metabolic effects through novel mechanisms, including modulation of TLR2/4 and JAK/STAT pathways. This review highlights its unique multi-component structure that enables synergistic biological activity, and its pharmacological properties, which underlies its ability to enhance intestinal barrier integrity, restore microbiota balance, and suppress systemic inflammation. Crucially, Amuc_1100 demonstrates unprecedented therapeutic versatility across both intestinal disorders (e.g., inflammatory bowel disease, antibiotic-associated diarrhea) and extraintestinal conditions-notably improving neuropsychiatric symptoms via gut-serotonin axis regulation, combating cancer through CD8+ T cell activation, and mitigating cardiotoxicity via gut-heart immune crosstalk. Emerging innovations in targeted delivery systems, including gut-retentive nano-formulations and engineered probiotic vectors, further amplify its clinical potential. We critically evaluate recent advances distinguishing Amuc_1100's mechanisms from live bacterial interventions. By synthesizing evidence from preclinical models, this work positions Amuc_1100 as a prototype for next-generation microbiome-derived therapeutics, bridging microbial ecology with precision medicine.

Research Status and Trends of Gut Microbiota and Intestinal Diseases Based on Bibliometrics

Gut microbiota plays an important role in gut health, and its dysbiosis is closely related to the pathogenesis of various intestinal diseases. The field of gut microbiota and intestinal diseases has not yet been systematically quantified through bibliometric methods. This study conducted bibliometric analysis to delineate the evolution of research on gut microbiota and intestinal diseases. Data were sourced from the Web of Science Core Collection database from 2009 to 2023 and were scientometrically analyzed using CiteSpace. We have found that the number of annual publications has been steadily increasing and showing an upward trend. China and the Chinese Academy of Sciences are the country and institution with the most contributions, respectively. Frontiers in Microbiology and Nutrients are the journals with the most publications, while Plos One and Nature are the journals with the most citations. The field has shifted from focusing on traditional descriptive analysis of gut microbiota composition to exploring the causal relationship between gut microbiota and intestinal diseases. The research hotspots and trends mainly include the correlation between specific intestinal diseases and gut microbiota diversity, the mechanism of gut microbiota involvement in intestinal diseases, the exploration of important gut microbiota related to intestinal diseases, and the relationship between gut microbiota and human gut health. This study provides a comprehensive knowledge map of gut microbiota and intestinal diseases, highlights key research areas, and outlines potential future directions.

Using nutrition to help recovery from infections

PURPOSE OF REVIEW

Antibiotics are a cornerstone of modern medicine, but antibiotic consumption can have depleting effects on the gut microbiota, potentially leading to gastrointestinal symptoms and other diseases, namely Clostridioides difficile infection. Because nutrition is a major driver of gut microbiota diversity and function, here we explore the current evidence on the potential of diets in alleviate the deleterious effects of antibiotics consumed during infections.

RECENT FINDINGS

Beneficial nutrients can enhance the symbiotic effect of the gut microbiota with the host, supporting anti-inflammatory responses and maintaining tight junction integrity. Short-chain fatty acids have been shown to positively affect the immune response, reducing the severity of C. difficile infection, whereas high-fibre diets have been shown to promote faster recovery of the gut microbiota after antibiotic therapy.

SUMMARY

The role of nutrition during infection is gaining momentum, with key findings exploring the effect of some nutrients in limiting the severity of infections and helping the microbiota recover from antibiotic-induced dysbiosis. Although this field is in its infancy, these findings open the possibility of personalised nutrition as a way of restoring microbiome diversity. But more work is needed to identify the most effective types and combinations of nutrients to achieve this.

The Aging Stomach: Clinical Implications of H. pylori Infection in Older Adults-Challenges and Strategies for Improved Management

Aging is a multifactorial biological process characterized by a decline in physiological function and increasing susceptibility to various diseases, including malignancies and gastrointestinal disorders. Helicobacter pylori (H. pylori) infection is highly prevalent among older adults, particularly those in institutionalized settings, contributing to conditions such as atrophic gastritis, peptic ulcer disease, and gastric carcinoma. This review examines the intricate interplay between aging, gastrointestinal changes, and H. pylori pathogenesis. The age-associated decline in immune function, known as immunosenescence, exacerbates the challenges of managing H. pylori infection. Comorbidities and polypharmacy further increase the risk of adverse outcomes in older adults. Current clinical guidelines inadequately address the specific needs of the geriatric population, who are disproportionately affected by antibiotic resistance, heightened side effects, and diagnostic complexities. This review focuses on recent advancements in understanding H. pylori infection among older adults, including epidemiology, diagnostics, therapeutic strategies, and age-related gastric changes. Diagnostic approaches must consider the physiological changes that accompany aging, and treatment regimens need to be carefully tailored to balance efficacy and tolerability. Emerging strategies, such as novel eradication regimens and adjunctive probiotic therapies, show promise for improving treatment outcomes. However, significant knowledge gaps persist regarding the impact of aging on H. pylori pathogenesis and treatment efficacy. A multidisciplinary approach involving gastroenterologists, geriatricians, and other specialists is crucial to providing comprehensive care for this vulnerable population. Future research should focus on refining diagnostic and therapeutic protocols to bridge these gaps, ultimately enhancing clinical outcomes and reducing the burden of H. pylori-associated diseases in the aging population.

Comparative evaluation of fermented ginseng on alleviating antibiotic-associated diarrhea in mice

Antibiotic associated diarrhea (AAD) was a common side effect of antibiotics, and fermented ginseng exhibited potential in treating AAD. In this study, the effects of fermented red, white, and black ginseng on AAD were investigated, with a focus on intestinal flora and inflammation. Clindamycin was used to induce AAD in mice, which caused severe diarrhea and weight loss. However, treatment with fermented ginseng effectively alleviated diarrhea, and reduced inflammation in colonic serosal tissue, thereby mitigating antibiotic-induced intestinal tissue damage. 16S rRNA sequencing revealed that clindamycin disrupted the Bacteroides/Firmicutes ratio (P < 0.001), which was reversed by fermented ginseng treatment. Furthermore, inflammatory cytokines like IL-1β, IL-6, and TNF-α significantly decreased (P < 0.05) after clindamycin treatment but returned to normal levels following fermented ginseng treatment. In conclusion, fermented red, white, or black ginseng (at a dosage of 0.5 g/kg) exhibited efficacy against AAD in mice, reinstating gut flora balance and easing inflammation.

Interpretable machine learning models for predicting the incidence of antibiotic- associated diarrhea in elderly ICU patients

BACKGROUND

Antibiotic-associated diarrhea (AAD) can prolong hospitalization, increase medical costs, and even lead to higher mortality rates. Therefore, it is essential to predict the incidence of AAD in elderly intensive care unit(ICU) patients. The objective of this study was to create a prediction model that is both interpretable and generalizable for predicting the incidence of AAD in elderly ICU patients.

METHODS

We retrospectively analyzed data from the First Medical Center of the People's Liberation Army General Hospital (PLAGH) in China. We utilized the machine learning model Extreme Gradient Boosting (XGBoost) and Shapley's additive interpretation method to predict the incidence of AAD in elderly ICU patients in an interpretable manner.

RESULTS

A total of 848 adult ICU patients were eligible for this study. The XGBoost model predicted the incidence of AAD with an area under the receiver operating characteristic curve (ROC) of 0.917, sensitivity of 0.889, specificity of 0.806, accuracy of 0.870, and an F1 score of 0.780. The XGBoost model outperformed the other models, including logistic regression, support vector machine (AUC = 0.809), K-nearest neighbor algorithm (AUC = 0.872), and plain Bayes (AUC = 0.774).

CONCLUSIONS

While the XGBoost model may not excel in absolute performance, it demonstrates superior predictive capabilities compared to other models in forecasting the incidence of AAD in elderly ICU patients categorized based on their characteristics.

Preliminary Analysis of Gut Microbiome and Gastrointestinal Symptom Burden in Breast Cancer Patients Receiving Chemotherapy Compared to Healthy Controls

BACKGROUND

Alterations in the naturally occurring bacteria of the gut, known as the gastrointestinal (GI) microbiome, may influence GI symptoms in women with breast cancer.

OBJECTIVE

This work aims to describe GI symptom occurrence, duration, severity, and distress and measures of the GI microbiome among women with breast cancer receiving chemotherapy compared to age- and sex-matched healthy controls.

INTERVENTIONS/METHODS

22 women with breast cancer receiving chemotherapy and 17 healthy control women provided stool specimens and GI symptom data using the modified Memorial Symptom Assessment Scale (MSAS). The fecal microbiome was profiled by metagenomic sequencing of 16S Ribosomal RNA (rRNA). GI microbiome was compared between groups using alpha-diversity (Observed OTU number and Shannon index), beta-diversity (UniFrac distances), and relative abundance of select genera.

RESULTS

GI symptoms with high symptom reports among breast cancer patients included nausea, diarrhea, flatulence, dry mouth, taste change, and poor appetite. Indices of differential abundance (beta diversity) significantly distinguished between breast cancer patients and healthy controls. Unique bacterial features differentiating the 2 groups were Prevotella_9, Akkermansia, Lachnospira, Lachnospiraceae_NK4A136, Lachnoclostridium, and Oscillibacter.

CONCLUSIONS

Gut bacteria are associated with GI inflammation and mucus degradation, suggesting the potential role of the GI microbiome in GI symptom burden. Understanding the influence of GI bacteria on gut health and symptoms will help harness the enormous potential of the GI microbiome as a future diagnostic and therapeutic agent to reduce the symptom burden associated with chemotherapy.

The interaction between Mediterranean diet and intestinal microbiome: relevance for preventive strategies against frailty in older individuals

Age-related changes in intestinal microbiome composition and function are increasingly recognized as pivotal in the pathophysiology of aging and are associated with the aging phenotype. Diet is a major determinant of gut-microbiota composition throughout the entire lifespan, and several of the benefits of a healthy diet in aging could be mediated by the microbiome. Mediterranean diet (MD) is a traditional dietary pattern regarded as the healthy diet paradigm, and a large number of studies have demonstrated its benefits in promoting healthy aging. MD has also a positive modulatory effect on intestinal microbiome, favoring bacterial taxa involved in the synthesis of several bioactive compounds, such as short-chain fatty acids (SCFAs), that counteract inflammation, anabolic resistance, and tissue degeneration. Intervention studies conducted in older populations have suggested that the individual response of older subjects to MD, in terms of reduction of frailty scores and amelioration of cognitive function, is significantly mediated by the gut-microbiota composition and functionality. In this context, the pathophysiology of intestinal microbiome in aging should be considered when designing MD-based interventions tailored to the needs of geriatric patients.

Roles and regulation of Aquaporin-3 in maintaining the gut health: an updated review

Aquaporin-3 (AQP3) is a predominant water channel protein expressed in the intestine, and plays important roles in the gut physiology and pathophysiology due to its permeability to water, glycerol and hydrogen peroxide. In this review, we systematically summarized the current understanding of the expression of AQP3 in the intestine of different species, and focused on the potential roles of AQP3 in water transport, different types of diarrhea and constipation, intestinal inflammation, intestinal barrier function, oxidative stress, and autophagy. These updated findings have supported that AQP3 may function as an important target in maintaining gut health of human and animals.