Search Results (465)

Coastal ecosystems are increasingly threatened by climate change and anthropogenic pressures, which can disrupt microbial communities and favor the emergence of pathogenic organisms. In this study, we applied metagenomic analysis to characterize fungal communities in sediment samples from an urban mangrove subjected to environmental stress. The results revealed a fungal community with reduced richness—28% lower than expected for similar ecosystems—likely linked to physicochemical changes such as heavy metal accumulation, acidic pH, and eutrophication, all typical of urbanized coastal areas. Notably, we detected an increase in potentially pathogenic genera, including Candida, Aspergillus, and Pseudoascochyta, alongside a decrease in key saprotrophic genera such as Fusarium and Thelebolus, indicating a shift in ecological function. The fungal assemblage was dominated by the phyla Ascomycota and Basidiomycota, and despite adverse conditions, symbiotic mycorrhizal fungi remained present, suggesting partial resilience. A considerable fraction of unclassified fungal taxa also points to underexplored microbial diversity with potential ecological or health significance. Importantly, this study does not aim to compare pristine and contaminated environments, but rather to provide a sanitary alert by identifying the presence and potential proliferation of pathogenic fungi in a degraded mangrove system. These findings highlight the sensitivity of mangrove fungal communities to environmental disturbance and reinforce the value of metagenomic approaches for monitoring ecosystem health. Incorporating fungal metagenomic surveillance into environmental management strategies is essential to better understand biodiversity loss, ecological resilience, and potential public health risks in degraded coastal environments. Full article

Autism spectrum disorder (ASD) is increasingly associated with microbial and metabolic disturbances, including the altered production of gut-derived uremic toxins. We investigated urinary concentrations of five representative uremic toxins—indoxyl sulfate (IS), p-cresyl sulfate (PCS), trimethylamine N-oxide (TMAO), asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA)—in 161 children with ASD and 71 healthy controls. Toxins were measured using LC-MS/MS and were normalized to creatinine. Subgroup analyses were performed by sex, age group (2–5.9 vs. 6–17 years), and autism severity based on the Childhood Autism Rating Scale (CARS). In addition to individual concentrations, we calculated the total toxin burden, proportional contributions, and functional ratios (IS/PCS, PCS/TMAO, and IS/ADMA). While individual toxin levels did not differ significantly between groups, stratified analyses revealed that PCS was higher in girls and in severe cases of ASD, whereas IS and TMAO were reduced in younger and more severely affected children. The functional ratios shifted consistently with severity—IS/PCS declined from 1.69 in controls to 0.99 in severe cases of ASD, while PCS/TMAO increased from 12.2 to 20.5. These patterns suggest a phenolic-dominant microbial signature and an altered host–microbial metabolic balance in ASD. Functional toxin profiling may offer a more sensitive approach to characterizing metabolic disturbances in ASD than concentration analysis alone. Full article

Background: Depression is a mental disorder characterized by a combination of somatic and cognitive disturbances, in which a predominantly sad or irritable mood significantly interferes with the patient’s functioning. This condition can affect individuals of all ages and socioeconomic backgrounds. Currently, various studies are exploring a possible association between oral dysbiosis and depression—an increasingly relevant topic, as confirmation of such a relationship could position the oral microbiota as a potential etiological or diagnostic factor for depression, given its accessibility and ease of analysis. Aim: To present a qualitative synthesis of studies addressing how oral dysbiosis influences the onset of depression, as well as the importance of controlling this alteration of the oral microbiota to aid in the prevention of the disease. Materials and Methods: The PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) outline the procedures to be followed for conducting this systematic review. The article search was carried out on 22 May 2025, across the PubMed, Scopus, Scielo, and The Cochrane Library databases, using terms related to “depression” and “oral dysbiosis”. Studies published within the last 10 years that addressed the potential association between oral dysbiosis, and depression were included. Furthermore, the quality of the studies was assessed using various tools depending on their design: the Newcastle–Ottawa Scale (NOS) was applied to case-control and cohort studies; the Joanna Briggs Institute (JBI) critical appraisal checklist was used for cross-sectional studies; and experimental studies were evaluated using SYRCLE’s Risk of Bias Tool. Results: A total of eleven studies were included in this systematic review. The findings suggest the presence of alterations in the oral microbiota of patients with depression, particularly in terms of composition, structure, and diversity. A reduction in alpha diversity—an indicator of local microbial balance—was observed, along with an increase in beta diversity, indicating greater inter-individual variability, which may be associated with inflammatory processes or immunological dysfunctions. Some studies reported differing results, which may be attributable to methodological variability regarding study design, or the populations sampled. Conclusions: This systematic review suggests that the oral microbiome could be considered a diagnostic biomarker and therapeutic target for depression, as the analyzed studies demonstrate a significant association between oral microbiome dysbiosis and this mental disorder. However, the methodological heterogeneity among the studies highlights the need for further research to confirm this potential relationship. Full article

Diabetic foot ulcers (DFUs), which affect approximately 15% of individuals with diabetes mellitus (DM), result from complex molecular disturbances involving chronic hyperglycemia, immune dysfunction, and infection. At the molecular level, chronic hyperglycemia promotes the formation of advanced glycation end products (AGEs), activates the AGE-RAGE-NF-κB axis, increases oxidative stress, and impairs macrophage polarization from the pro-inflammatory M1 to the reparative M2 phenotype, collectively disrupting normal wound healing processes. The local wound environment is further worsened by antibiotic-resistant polymicrobial infections, which sustain inflammatory signaling and promote extracellular matrix degradation. The rising threat of antimicrobial resistance complicates infection management even further. Recent studies emphasize that optimal glycemic control using antihyperglycemic agents such as metformin, Glucagon-like Peptide 1 receptor agonists (GLP-1 receptor agonists), and Dipeptidyl Peptidase 4 enzyme inhibitors (DPP-4 inhibitors) improves overall metabolic balance. These agents also influence angiogenesis, inflammation, and tissue regeneration through pathways including AMP-activated protein kinase (AMPK), mechanistic target of rapamycin (mTOR), and vascular endothelial growth factor (VEGF) signaling. Evidence indicates that maintaining glycemic stability through continuous glucose monitoring (CGM) and adherence to antihyperglycemic treatment enhances antibiotic effectiveness by improving immune cell function and reducing bacterial virulence. This review consolidates current molecular evidence on the combined effects of glycemic and antibiotic therapies in DFUs. It advocates for an integrated approach that addresses both metabolic and microbial factors to restore wound homeostasis and minimize the risk of severe outcomes such as amputation. Full article

Emerging evidence highlights the critical role of the gut microbiota in the development and progression of eating disorders (EDs), particularly in women, who are more frequently affected by these conditions. Women with anorexia nervosa, bulimia nervosa, and binge eating disorder exhibit distinct alterations in gut microbiota composition compared to healthy controls. These alterations, collectively termed dysbiosis, involve reduced microbial diversity and shifts in key bacterial populations responsible for regulating metabolism, inflammation, and gut–brain signaling. The gut microbiota is known to influence appetite regulation, mood, and stress responses—factors closely implicated in the pathogenesis of EDs. In women, hormonal fluctuations related to menstruation, pregnancy, and menopause may further modulate gut microbial profiles, potentially compounding vulnerabilities to disordered eating. Moreover, the restrictive eating patterns, purging behaviors, and altered dietary intake often observed in women with EDs exacerbate microbial imbalances, contributing to intestinal permeability, low-grade inflammation, and disturbances in neurotransmitter production. This evolving understanding suggests that microbiota-targeted therapies, such as probiotics, prebiotics, dietary modulation, and fecal microbiota transplantation (FMT), could complement conventional psychological and pharmacological treatments in women with EDs. Furthermore, precision nutrition and personalized microbiome-based interventions tailored to an individual’s microbial and metabolic profile offer promising avenues for improving treatment efficacy, even though these approaches remain exploratory and their clinical applicability has yet to be fully validated. Future research should focus on sex-specific microbial signatures, causal mechanisms, and microbiota-based interventions to enhance personalized treatment for women struggling with eating disorders. Full article

Understanding the processes that drive microbial community assembly is a fundamental question in ecology, with important implications for predicting community responses to environmental disturbances. River ecosystems are under growing pressure from human disturbances, jeopardizing their ecological functions. Here, we investigated bacterial and protistan communities along the Yujiang River using environmental DNA metabarcoding. Bacterial communities exhibited significantly greater alpha diversity and broader habitat niches compared to protists. Additionally, a negative correlation was found between alpha diversity and niche breadth for both groups. Protistan communities exhibited significantly higher beta diversity (Bray–Curtis distance) than bacterial communities, with species turnover being the principal factor driving the variations in both communities. Null model results indicated that heterogeneous selection primarily structured bacterial communities, while stochastic processes (drift) mainly governed protist communities. Redundancy analysis and Mantel tests showed significant associations between environmental factors (e.g., temperature and pH) and bacterial community composition. Moreover, the longitude of sampling sites was linked to spatial variations in both bacterial and protistan communities. Further analyses, including distance-decay patterns, variation partitioning, and multiple regression on distance matrices, demonstrated that bacterial communities were driven by both environmental and spatial factors, while protist communities exhibited a stronger response to spatial factors. These results enhance our understanding of microbial community assembly in river ecosystems and provide valuable insights for the conservation and sustainable management of freshwater systems. Full article

Petroleum-derived contaminants pose a significant threat to the soil microbiome. Therefore, it is essential to explore materials and techniques that can restore homeostasis in disturbed environments. The aim of the study was to assess the response of the soil microbiome to contamination with diesel oil (DO) and gasoline (G) and to determine the capacity of sorbents, vermiculite (V), dolomite (D), perlite (P) and agrobasalt (A), to enhance the activity of microorganisms under Zea mays cultivation conditions in pot experiments. The restoration and activity of the soil microbiome were evaluated based on the abundance and diversity of bacteria and fungi, using both classical microbiological methods and Next Generation Sequencing (NGS). Bioinformatic tools were employed to calculate the physicochemical properties of proteins. DO increased the abundance of cultured microorganisms, whereas G significantly reduced it. Both DO and G increased the number of ASVs of Proteobacteria and decreased the relative abundance of Gemmatimonadetes, Chloroflexi, Acidobacteria, Verrucomicrobia, Planctomycetes, and fungal OTUs. These contaminants stimulated the growth of bacteria from the genera Rhodanobacter, Sphingomonas, Burkholderia, Sphingobium, and Mycobacterium, as well as fungi belonging to the Penicillium genus. Conversely, they had a negative effect on Kaistobacter, Rhodoplanes, and Ralstonia, as well as the fungi Chaetomium, Pseudaleuria, and Mortierella. DO caused greater changes in microbial alpha diversity than G. The stability of microbial proteins was higher at 17 °C than at −1 °C. The most stable proteins were found in bacteria and fungi identified within the core soil microbiome. These organisms exhibited greater diversity and more compact RNA secondary structures. The application of sorbents to contaminated soil altered the composition of bacterial and fungal communities. All sorbents enhanced the growth of organotrophic bacteria (Org) and fungi (Fun) in DO-contaminated soils, and actinobacteria (Act) and fungi in G-contaminated soils. V and A had the most beneficial effects on cultured microorganisms. In DO-contaminated soils, all sorbents inhibited the growth of Rhodanobacter, Parvibaculum, Sphingomonas, and Burkholderia, while stimulating Salinibacterium and Penicillium. In G-contaminated but otherwise unamended soils, all sorbents negatively affected the growth of Burkholderia, Sphingomonas, Kaistobacter, Rhodoplanes, Pseudonocardia, and Ralstonia and increased the abundance of Gymnostellatospora. The results of this study provide a valuable foundation for developing effective strategies to remediate soils contaminated with petroleum-derived compounds. Full article

Investigating the effects of fire disturbance on soil microbial diversity and nitrogen cycling is crucial for understanding the mechanisms underlying soil nitrogen cycling. This study examined the fire burn site of the Larix gmelinii forest in the Greater Khingan Mountains, Inner Mongolia, to analyze the impact of varying fire intensities on soil nitrogen, microbial communities, and the abundance of nitrogen cycle-related functional genes after three years. The results indicated the following findings: (1) Soil bulk density increased significantly following severe fires (7.06%~10.84%, p < 0.05), whereas soil water content decreased with increasing fire intensity (6.62%~19.42%, p < 0.05). The soil total nitrogen and ammonium nitrogen levels declined after heavy fires but increased after mild fires; (2) Mild fire burning significantly increased soil bacterial diversity, while heavy fire had a lesser effect. Dominant bacterial groups included Xanthobacteraceae, norank_o_norank_c_AD3, and norank_o_Elsterales. Norank_o_norank_c_AD3 abundance decreased with burn intensity (7.90% unburned, 3.02% mild fire, 2.70% heavy fire). Conversely, norank_o_Elsterales increased with burning (1.23% unburned, 5.66% mild fire, 5.48% heavy fire); (3) The abundance of nitrogen-fixing nifH functional genes decreased with increasing fire intensity, whereas nitrification functional genes amoA-AOA and amoA-AOB exhibited the opposite trend. Light-intensity fires increased the abundance of denitrification functional genes nirK, nirS, and nosZ, while heavy fires reduced their abundance; (4) The correlation analysis demonstrated a strong association between soil bacteria and denitrification functional genes nifH and amoA-AOA, with soil total nitrogen being a key factor influencing the nitrogen cycle-related functional genes. The primary bacterial groups involved in soil nitrogen cycling were Proteobacteria, Actinobacteria, and Chloroflexi. These findings play a critical role in promoting vegetation regeneration and rapid ecosystem restoration in fire-affected areas. Full article

(1) Background: Second-generation integrase strand transfer inhibitors (INSTIs) are now the preferred first-line therapies for human immunodeficiency virus (HIV). However, concerns regarding their side effects, such as weight gain and metabolic disturbances, have emerged. This scoping review aims to assess the effects of INSTIs on the gut microbiota, with a focus on differences between agents and their clinical implications. (2) Methods: A scoping review was conducted using PubMed, Web of Science, and Embase, with reports collected following PRISMA for Scoping Reviews (PRISMA-ScR). (3) Results: The majority of available evidence focused on dolutegravir, which demonstrated beneficial effects on microbiota diversity and composition. However, factors such as younger age, lower CD4+ counts, and extreme BMI were associated with proinflammatory changes. Limited data on bictegravir also suggested favorable alterations in the gut microbiota. Raltegravir, a first-generation INSTI, was associated with improvements in alpha diversity and microbial composition, although these changes were not consistently beneficial. Moreover, associated changes in inflammatory and microbial translocation markers suggested unfavorable alterations. (4) Conclusions: Based on the evidence mapped, second-generation INSTIs may generally induce favorable changes in the gut microbiota. However, further research is needed to explore the clinical implications of these microbiota alterations, particularly in specific patient groups. Full article

Urban soils are subject to intense anthropogenic disturbance, often resulting in biodiversity loss and reduced ecosystem functionality. However, rhizospheric microbial communities help maintain critical soil-ecosystem services, supporting urban soil resilience. This study evaluated the diversity of culturable bacteria associated with the rhizospheres of Pennisetum clandestinum and Pseudelephantopus spicatus in green areas of Medellín, Colombia, under contrasting levels of anthropic pressures. Rhizospheric and non-rhizospheric soils were sampled near automotive mechanic sites, and bacterial communities were assessed through plate counting and morphological characterization. Alpha, beta, and rarefaction diversity indices were applied to evaluate culturable morphotypes. P. clandestinum supported a more diverse and complex rhizospheric microbiome, particularly in non-exposed soils, while P. spicatus hosted less diverse communities under similar conditions. Diversity indices effectively distinguished microbial patterns, demonstrating the utility of culture-based methods for microbial community assessment. As a first step in microbial bioprospecting workflows, these methods allow for the rapid screening of culturable diversity and support decision-making for the selection of promising environments, plant species, and microbial isolates. This approach can inform urban soil threats, the promotion of beneficial plant–microbe interactions, and the identification of bioindicator species for soil health monitoring in a framework for the management of green areas. Full article

Potamogeton crispus (P. crispus), with strong nitrogen uptake capacity, plays an important ecological role during winter and early spring when most aquatic plants are inactive. Its presence can also influence microbial denitrification in sediments by regulating oxygen levels and organic carbon availability. In this study, an indoor hydroponic simulation system was used to systematically evaluate the effects of P. crispus under different nitrogen-loading conditions on nitrogen removal from water, changes in sediment carbon and nitrogen fractions, microbial community structure, and greenhouse gas fluxes. The results showed that P. crispus effectively removed TN, NH₄⁺-N, NO₃⁻-N, and NO₂⁻-N, maintaining strong denitrification capacity even under high-nitrogen loading. Under all nitrogen conditions, TN removal exceeded 80%, while NH₄⁺-N and NO₃⁻-N removal efficiencies surpassed 90%, with effective suppression of NO₂⁻-N accumulation. Rhizosphere-mediated regulation by P. crispus enhanced the transformation and stabilization of DOC and NO₃⁻-N in sediments, while also mitigating nitrogen-induced disturbances to carbon–nitrogen balance. The plant also exhibited strong CO₂ uptake capacity, low CH₄ emissions with a slight increase under higher nitrogen loading, and N₂O fluxes that were significantly affected by nitrogen levels—showing negative values under low nitrogen and sharp increases under high-nitrogen conditions. Correlation analyses indicated that CO₂ and N₂O emissions were mainly regulated by microbial taxa involved in carbon and nitrogen transformation, while CH₄ emissions were primarily driven by methanogenic archaea and showed weaker correlations with environmental factors. These findings highlight the importance of water restoration during low-temperature seasons and provide a theoretical basis for integrated wetland management strategies aimed at coordinated pollution reduction and carbon mitigation. Full article

Engineering disturbances are increasing in permafrost regions of northeastern China, where soil microorganisms play essential roles in biogeochemical cycling and are highly sensitive to linear infrastructure disturbances. However, limited research has addressed how microbial communities respond to different post-engineering-disturbance recovery stages. This study investigated the impacts of the China–Russia Crude Oil Pipelines (CRCOPs) on soil microbial communities in a typical boreal forest permafrost zone of the Da Xing’anling Mountains. Soil samples were collected from undisturbed forest (the control, CK); short-term disturbed sites associated with Pipeline II, which was constructed in 2018 (SD); and long-term disturbed sites associated with Pipeline I, which was constructed in 2011 (LD). Pipeline engineering disturbances significantly increased soil clay content and pH while reducing soil water content (SWC), soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) (p < 0.05). No significant differences in these soil properties were observed between SD and LD. Bacterial diversity increased significantly, whereas fungal diversity significantly decreased following pipeline disturbances (p < 0.05). The beta diversity of both bacterial and fungal communities differed significantly among the three disturbance types. At the phylum level, pipeline disturbance increased the relative abundances of Proteobacteria, Acidobacteriota, Actinobacteriota, Ascomycota, and Mortierellomycota while reducing those of Bacteroidota and Basidiomycota. These shifts were associated with disturbance-induced changes in soil properties. Microbial co-occurrence networks in SD exhibited greater complexity and connectivity than those in CK and LD, suggesting intensified biotic interactions and active ecological reassembly during the early recovery phase. These findings suggest that pipeline disturbance could drive soil microbial systems into a new stable state that is difficult to restore over the long term, highlighting the profound impacts of linear infrastructure on microbial ecological functions in cold regions. This study provides a scientific basis for ecological restoration and biodiversity conservation in permafrost-affected areas. Full article

In recent years, tires have become a prominent concern for researchers and environmentalists in regard to their potential threat of tire-derived pollutants (TDPs) to human health. Among these pollutants, N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD) and its oxidized form, 6PPD-quinone (6PPD-Q), have been of primary interest due their ubiquity in urban environments, and their potential negative effects on human health. This review provides a summary of human health implications of TDPs, including 6PPD and 6PPD-Q. For the methodology, datasets were collected from the literature sources, including sources, formations and ecological effects of these pollutants, and pathways of human exposure and public health significance. Urban soils are key for services including carbon storage, water filtration, and nutrient cycling, underpinning urban ecosystem resilience. Soil degradation through compaction, sealing, and pollution, particularly by pollutants from tire wear, destroys these functions, however. These pollutants disturb the soil microbial communities, leading to a loss of diversity, an increase in pathogenic species, and changes in metabolism, which in turn can impact human health by increasing disease transmission and diseases of the respiratory systems. Incorporating green-infrastructure practices can enhance the ecosystem service potentials of urban soils and contribute to sustainable, climate-resilient urban city development. These findings underscore the pressing need for a coordinated international campaign to study chronic health effects and science informed policy frameworks to address this ubiquitous environmental health concern—an issue that crosses urban water quality, environmental justice, and global management of tire pollution. Full article

Osteoarthritis (OA) has traditionally been defined as a degenerative joint disease driven by mechanical wear, aging, and metabolic disturbances. However, emerging evidence suggests that joint dysbiosis, a dysregulation in the joint microbiome, may play an important role in OA pathogenesis. This review explores the mechanisms linking dysbiosis to OA. We examine the presence and origin of joint dysbiosis, also highlighting the gut–joint and oral–joint axes as potential routes for microbial translocation. However, challenges remain in distinguishing causation from correlation and addressing microbial contaminants in microbiome studies. Future research should prioritize longitudinal studies and multiomics integration to elucidate the complex interplay between microbial communities and joint health. Full article

Diversified agricultural practices reconfigure agroecosystem services by modifying fertilization, tillage intensities, and cropping patterns, altering soil properties and microbial assemblages. However, microbial communities, as critical bioindicators of soil health and productivity, respond to agricultural disturbances, and the effects of multiple practices on productivity-associated indicator species require further validation. Using 16S and ITS amplicon sequencing, this study employed a field experiment to investigate the effects of agricultural practices on soil properties, maize productivity, and microbial communities under two fertilization treatments. Within each treatment, we assessed correlations between indicator species associated with cropping–tillage practices and soil productivity. Results showed that fertilization significantly altered soil properties, increased maize grain yield by 23.9%, and reshaped bacterial and fungal community structures, increasing bacterial richness by 23% but reducing fungal richness and Shannon index by 15% and 20%, respectively. Furthermore, cropping–tillage practices significantly affected microbial communities and grain yields in both fertilized and unfertilized treatments despite a slight influence on soil properties. Distinct sets of bacterial and fungal indicator species were identified for each fertilization treatment: unfertilized soils harbored 21 dominant bacterial indicator species (e.g., Bacillus, Rhizobium, Streptomyces) and 8 fungal indicators (e.g., Cryptococcus, Gibberella, Tetracladium); fertilized soils contained 24 dominant bacterial indicators (e.g., Fusobacterium, Clostridium, Lactobacillus) and 6 fungal indicators (e.g., Gibberella, Cladosporium, Mortierella). Notably, abundances of specific indicator genera (e.g., bacteria: Bacteroides, Gemmatirosa, Iamia, Lysobacter, Prevotella, Staphylococcus, Sutterella; fungi: Glomus, Fusicolla in unfertilized soil; bacteria: Dinghuibacter, Haliangium, Kribbella, Rhodomicrobium, Terrimonas; fungi: Pulvinula in fertilized soil) correlated positively with grain yields. These findings demonstrate that fertilization reshapes the composition of microbial indicator species significantly associated with maize productivity. Tailored microbial indicator assemblages specific to distinct fertilization strategies are therefore essential for evaluating crop productivity and assessing agricultural practice impacts. Consequently, monitoring these indicator species enables rapid assessment of soil fertility changes, offering guidance for fertilization management. Full article