Search Results (730)

Background/Objectives: Chronic pain is increasingly conceptualized as a systemic condition characterized by central sensitization, autonomic dysregulation, and persistent neuroimmune and neuroendocrine alterations. These systemic changes have been linked to microbial dysbiosis, most prominently within the gut microbiome. In contrast, the relevance of the urinary microbiome outside primary urological disease remains poorly understood, particularly in non-urological chronic pain conditions. The objective of this study was to determine whether patients with chronic low back pain exhibit differences in urinary microbial diversity, community composition, or taxon-specific abundance compared with pain-free controls. Methods: In this age- and sex-matched case–control study, midstream urine samples were collected from ten patients with chronic low back pain and ten pain-free controls and analyzed using 16S rRNA gene sequencing (V4 region). Sequence data were processed using nf-core/ampliseq and DADA2. Alpha diversity, beta diversity, and differential abundance were assessed using depth-adjusted models, compositional and phylogenetically informed distance metrics, and ANCOM-BC2, with multiple sensitivity analyses to account for the low-biomass nature of urinary microbiome data. Results: After accounting for sequencing depth, no significant differences in alpha diversity were observed between patients and controls for any metric. Beta diversity analyses revealed no significant differences in overall community composition between groups across all distance measures, and dispersion was comparable between groups. Differential abundance analysis did not identify any bacterial taxa that differed significantly between patients and controls after correction for multiple testing. Conclusions: In this cohort, chronic low back pain was not associated with detectable alterations in the urinary microbiome. These findings suggest that, unlike the gut microbiome, urinary microbial communities may be relatively stable in the context of non-urological chronic pain, highlighting the importance of phenotype specificity and multidimensional approaches in microbiome-based pain research. Full article

Sand fly midgut microbiota plays a critical role in shaping Leishmania development and vector competence, yet functional evidence from natural vector populations remains limited. In this study, sand flies were collected between 2020 and 2022 in Cukurova region, Türkiye to characterize the gut bacterial composition of Phlebotomus tobbi and evaluate the anti-leishmanial potential of cultivable isolates. A total of 1739 sand flies were captured (878 females, 861 males), of which Ph. tobbi was the predominant species (n = 1312). 16S rRNA amplicon sequencing (V4–V6) showed that the gut microbiota was dominated by Proteobacteria, with Erwinia aphidicola/persicina representing the most abundant species across all analyzed groups. Fourteen cultivable bacterial species were identified by MALDI-TOF MS, including Serratia liquefaciens, Pantoea agglomerans, and Micrococcus luteus. Functional XTT assays against Leishmania infantum promastigotes demonstrated variable inhibitory activity among isolates. The strongest leishmanicidal effects were observed with S. liquefaciens (32.3%) and M. luteus (28.8%). Morphological examination confirmed promastigote rounding and cell death in isolates showing >25% activity. These findings define the gut bacterial landscape of Ph. tobbi in an endemic region and identify bacterial taxa with in vitro anti-leishmanial activity, highlighting their potential for future microbiota-based or paratransgenic control strategies. Full article

Shilajit is a complex natural phytomineral substance whose composition and biological activity may vary depending on geographical origin. This study compared three commercially available Shilajit samples from Russia (S1), Nepal (S2), and Iran (S3) in terms of phenolic acid profile, antimicrobial activity, and their effects on selected intestinal microorganisms and β-glucuronidase activity after simulated gastrointestinal digestion. The samples differed markedly in their phenolic composition, with S3 showing the highest total content of the quantified phenolic acids. All samples exhibited antimicrobial activity, although their intensity depended on the microorganism tested. The in vitro digestion model revealed clear sample-dependent effects: S2 showed the lowest net β-glucuronidase activity and the most beneficial modulation of Lactobacillus and Bifidobacterium, whereas S1 exerted the strongest suppressive effect on Escherichia coli. In contrast, S3, despite the richest phenolic profile, showed the highest β-glucuronidase activity. These findings indicate that the biological activity of Shilajit depends not only on the quantified phenolic acids but also on the broader, region-specific chemical matrix of the material. Full article

Microplastic (MP) contamination has become a defining feature of twenty-first century environmental change, yet the toxicological and ecological consequences for amphibians and reptiles—two vertebrate classes already facing severe extinction pressures—remain fragmented across taxa, regions, and methodological traditions. Here, we synthesize field and experimental evidence from five continents to provide a taxonomically balanced, mechanistically grounded, and geographically explicit assessment of MP exposure, bioaccumulation, and toxicity in herpetofauna, drawing on a structured literature search in Web of Science, Scopus, and PubMed (January 2015—March 2026). Field detection rates of MPs in amphibian larvae range from 26% in conservatively screened Central European populations to 73–80% in anuran tadpoles from high-anthropogenic-pressure Anatolian catchments, with fibrous polyethylene terephthalate (PET), polyethylene (PE), and polypropylene (PP) particles dominating the detected burden. Mechanistic evidence converges on oxidative stress cascades, hypothalamic–pituitary–thyroid axis disruption, gut and cutaneous microbiome dysbiosis, and compromised antiviral and antifungal immunity, with the latter potentially amplifying vulnerability to Batrachochytrium dendrobatidis and to ranavirus. Among reptiles, sea turtles display near-universal MP ingestion with documented maternal transfer to eggs; freshwater turtles, terrestrial squamates, and crocodilians remain critically understudied. Three structural asymmetries constrain current ecotoxicological risk characterization: taxonomic bias toward anurans and sea turtles, geographic bias toward the Global North, and experimental bias toward acute, supra-environmental laboratory exposures using pristine, single-polymer particles that fail to capture the chemical complexity of weathered field mixtures. We argue that MP burden may warrant consideration as a candidate stressor criterion within IUCN Red List assessments and within environmental risk assessment frameworks for freshwater and terrestrial biodiversity once a robust quantitative relationship between MP burden and demographic decline or population-level fitness has been established, and propose six hypothesis-driven research priorities: methodological standardization, reptile toxicokinetics, transgenerational epigenetics, MP–pathogen microbiome interactions and their translation into population viability models, temperature × MP interaction under climate warming, and population-genetic consequences of contemporary MP-driven selection, as the most tractable avenues for ecotoxicological progress and for the development of herpetofauna-specific risk characterization frameworks. Full article

The gut microbiota of fish plays a crucial role in nutrition, metabolism and immune regulation, and is highly sensitive to environmental stressors such as pesticide exposure. This study investigated the effects of emamectin benzoate (EMB) exposure on Asian stinging catfish (Heteropneustes fossilis) gut microbiota using an integrated culture-dependent and culture-independent approach to assess functional and taxonomic dysbiosis. Gut smear samples from control and EMB-treated fish at two sublethal concentrations (0.5 µg/L and 5 µg/L) were analyzed for major functional bacterial groups, including heterotrophic, lipid-hydrolysing, starch-hydrolysing, spore-forming, and Gram-negative bacteria and Pseudomonas spp., using standard plate count techniques. In parallel, microbial community composition and diversity were examined through 16S rRNA (V3–V4 region) gene amplicon sequencing followed by bioinformatic analysis. Culture-based results showed a significant decline in total heterotrophic bacteria and key functional groups in EMB-treated fish, indicating suppression of microbial metabolic activity and functional imbalance. Lipid-hydrolysing and starch-hydrolysing bacteria showed pronounced sensitivity to pesticide exposure, while spore-forming bacteria exhibited a marked reduction, suggesting compromised microbial resilience. Although Gram-negative bacteria declined overall, Pseudomonas spp. displayed a non-linear response, with an initial decrease, followed by partial recovery under higher exposure. Culture-independent analysis demonstrated reduced alpha diversity, altered community structure, and taxonomic shifts in EMB-treated fish. Pseudomonadota exhibited a distinct pattern characterized by decline at 0.5 µg/L and partial recovery at 5 µg/L, reflecting adaptive tolerance rather than restoration of microbial homeostasis. Overall, the combined evidence indicates pronounced EMB-induced gut dysbiosis at both functional and compositional levels. This study highlights the fish gut microbiome as a sensitive biomarker of stress and underscores the ecological risks associated with EMB in aquatic environments. Full article

Leishmaniases are vector-borne diseases transmitted by phlebotomine sand flies. While bacterial associations in sand fly microbiota are well studied, fungal communities remain poorly characterized, despite their potential role in insect biology and parasite transmission. This study aimed to isolate and characterize yeast-like and filamentous fungi from different developmental stages of Lutzomyia longipalpis, the main vector of visceral leishmaniasis in the Americas, to expand knowledge on fungal microbiota and its possible relevance to vector–parasite interactions. Sand fly eggs, larvae, pupae, and adults were sampled from a laboratory colony. Fungi were isolated from insect tissues and diets using culture-based methods. Morphological identification was complemented by partial sequencing of the ITS1-5.8S-ITS2 rDNA region to identify the species. Four fungi were consistently recovered: Candida guilliermondii, Cutaneotrichosporon dermatis, Penicillium sp., and Aspergillus sp. Their presence varied across developmental stages. Presence in the gut was observed for Cu. dermatis, Penicillium sp. and Aspergillus sp. in larvae and C. guilliermondii in adult females. Evidence suggested their presence in different stages from larvae to pupae, and sex-specific differences in adults, with fungi detected only in females. This work documented the mycobiota that may be associated with L. longipalpis, including the first report of Cutaneotrichosporon in sand flies. These findings highlight fungi that may be potential modulators of sand fly biology and Leishmania development, warranting further investigation into their ecological and epidemiological roles. Full article

Familial Mediterranean Fever (FMF) is among the most frequent autoinflammatory diseases in populations originating from the area of Middle Eastern and Mediterranean countries. It is caused by mutations in the MEFV gene, which causes dysregulated pyrin expression and thus an immunologic anomaly. FMF is diagnosed by recurrent episodes of fever and serosal inflammation, predominantly peritonitis and pleuritis, as well as other systemic symptoms. Recent research is dedicated to searching for factors beyond genetic code contributing to how FMF evolves, the severity of its symptoms and response to conventional therapy—colchicine. These factors include epigenetic modifications of the MEFV gene and other environmental factors, such as cold exposure, stress, composition of gut flora and diet. Among these factors, vitamin D, best known for its classical role in musculoskeletal health, has emerged as a powerful immune modulator. It has been documented that vitamin D has been implicated in the regulation of pro-inflammatory cytokines and may modulate immune responses. Notably, in regions with some of the highest reported prevalences of MEFV mutations—likely reflecting Mediterranean populations more broadly—vitamin D concentrations are frequently low. This overlap raises the hypothesis that vitamin D deficiency may be associated with FMF pathogenesis, although current data are largely correlational and do not establish causality. In this review, we summarize current evidence on FMF pathogenesis, potential triggers, and vitamin D metabolism, and explore how vitamin D may modulate immune responses and intersect with key autoinflammatory pathways, considering whether adequate vitamin D supplementation could help reduce disease burden in some patients with FMF. Full article

Colorectal cancer (CRC) is an increasing health concern in low- and middle-income countries (LMICs), especially in Africa, driven by dietary shifts, urbanisation, infections, and limited treatment access. The gut microbiome plays a central role in CRC, while soil-transmitted helminths (STHs) exert complex effects that can promote or mitigate risk depending on species, infection intensity, and host context. This systematic review synthesised 17 human studies (2000–2026) examining helminth impacts on gut microbial diversity, revealing a dualistic pattern. Several studies reported that chronic or moderate helminth infections, such as Ascaris lumbricoides and Trichuris trichiura, were associated with increased bacterial richness and the expansion of beneficial taxa, including Paraprevotellaceae, Parabacteroides, Agathobacter, Ruminococcaceae, and Lactobacillus. These taxa are associated with the production of short-chain fatty acids (SCFAs), protection of the epithelial barrier, and regulation of the immune system, suggesting a potential buffering effect against inflammation-driven carcinogenesis. On the contrary, other studies demonstrated helminth-associated dysbiosis characterised by reduced diversity and enrichment of pro-inflammatory and oncogenic taxa. T. trichiura and Strongyloides stercoralis infections were associated with the expansion of Treponema succinifaciens, Streptococcus gallolyticus, Enterobacteriaceae, and Ruminococcus torques, which are linked to reduced gut microbiome diversity, pro-inflammatory states, and oncogenic processes. Furthermore, A. lumbricoides infections altered the host microbiome at the phylum level, with increased Proteobacteria and reduced Firmicutes and Bacteroidetes, alongside metabolome shifts in amino acid and lipid pathways that have been associated with tumourigenic processes. Collectively, the evidence shows that helminthiasis may either enrich potentially protective microbes or be associated with pro-tumourigenic dysbiosis, with outcomes shaped by species, infection intensity, and host context. Notably, none of the included studies directly assessed CRC, underscoring the fact that current evidence is indirect and mechanistic. Overall, helminths are associated with gut microbiome shifts in both potentially protective and potentially harmful directions. This systematic synthesis of human evidence provides an integrated understanding of how helminth-associated microbiome shifts may influence colorectal carcinogenesis and highlights the need for longitudinal mechanistic studies to clarify causality and inform biomarker discovery and prevention in endemic regions. Full article

Background/Objectives: Gut microbiota dysregulation has been increasingly implicated in the pathophysiology of autism spectrum disorder (ASD), yet clinical responses to standardized probiotic interventions remain inconsistent, likely reflecting substantial inter-individual variability in baseline microbiome composition, host–microbe interactions, immune tone, and metabolic function. Here, we present a pilot implementation of a metagenomics-guided, personalized synbiotic intervention in children with ASD using the Systematic Microbiome Assessment and Reconstruction Therapy (SMART) framework. Methods: Seven children (aged 5–12 years) underwent longitudinal fecal shotgun metagenomic profiling, and dietary habits, food sensitivities, and regional dietary background were recorded as contextual factors potentially influencing microbiome composition and response to intervention. Individualized synbiotic formulations were constructed based on microbial taxonomic composition and inferred functional capacity and iteratively refined over time. Gastrointestinal outcomes were assessed through caregiver-reported clinical observations, whereas behavioral changes were evaluated using standardized instruments. Results: Several participants demonstrated improvements in gastrointestinal symptoms and selected behavioral domains. Notably, in a subset of participants, improvements in gastrointestinal function preceded measurable behavioral changes. Conclusions: Although limited by a small sample size and lack of a control group, these findings provide preliminary evidence supporting the feasibility of implementing a metagenomics-guided personalized synbiotic framework in ASD and generate hypotheses for future investigation. This work presents a preliminary conceptual framework for integrating microbial composition and inferred functional profiling into individualized intervention design and highlights the potential value of microbiome-informed stratification in future studies of treatment response. Larger controlled studies with objective outcome measures are warranted to further evaluate feasibility, reproducibility, and potential clinical utility. Full article

The double-crested cormorant (Nannopterum auritum), a piscivorous bird endemic to North America, frequently forages in aquaculture ponds during migration and wintering, contributing to economic losses in catfish-producing regions of the southern United States. While interactions between cormorants and aquaculture systems are well documented, their associated microbial communities and genetic elements remain less characterized. In this exploratory study, Hi-C-enabled metagenomics was applied to fecal samples from two cormorants to generate a genome-resolved, descriptive analysis of gut microbial composition and to associate bacterial genomes with mobile genetic elements (MGEs), antimicrobial resistance genes (ARGs), and putative virulence-associated genes. Metagenome-assembled genomes (MAGs) included taxa reported in aquatic or animal-associated environments, including Edwardsiella tarda, Plesiomonas shigelloides, Clostridium perfringens, and Campylobacter volucris. ARGs were detected across multiple MAGs, with E. tarda harboring the greatest diversity. Hi-C-enabled linkage of plasmids and phages to putative hosts, providing structural insight into microbial organization. Analyses are descriptive (n = 2) and do not include statistical comparisons or diversity metrics. These findings demonstrate the utility of Hi-C for resolving gene–host associations and provide a framework for future studies of microbial connectivity in One Health contexts. Full article

Digestive tract structure is a key indicator of fish health and environmental adaptation, while seasonal dynamics of the gut microbiota reflect host responses to environmental changes. In this study, the digestive tract microstructure of Hypomesus nipponensis from Bosten Lake was characterized using H&E staining and scanning electron microscopy, followed by 16S rDNA gene V3-V4 region sequencing and analysis of the gut microbiota in spring, summer, and autumn. The results showed that the esophageal mucosa of H. nipponensis is a stratified columnar epithelium, with abundant gastric glands, and the circular muscle layer of the stomach caeca is significantly thickened (244.84 ± 49.01 μm). The pyloric caeca resemble the gut in structure; both are covered with dense microvilli on the luminal surface. Collectively, these features constitute the structural basis for its carnivorous diet. Microbiota analysis revealed that the diversity of gut microbiota fluctuated significantly with season: the Chao, Ace, and Sob indices in spring (144.63 ± 30.27) were significantly higher than in summer (82.13 ± 21.45) and autumn (83.25 ± 15.30) (p < 0.001), with no significant difference between summer and autumn (p > 0.05). The dominant marker genera of H. nipponensis in spring, summer, and autumn were Bacillus (31.60%), Clostridium (32.20%), and Sarcina (29.32%), respectively. This study describes the adaptive characteristics of the digestive tract structure and feeding habits of H. nipponensis and reveals the seasonal changes in its gut microbiota. Importantly, since the digestive tract structure data were collected only in summer, the direct relationship between the structure and seasonal microbial dynamics cannot be determined, and multi-season histological sampling is needed for further investigation. Nevertheless, these findings provide preliminary morphological and microbiological references for the ecological adaptation of this species in Bosten Lake and offer a scientific basis for water resource management in this area. Full article

CRC remains a major cause of cancer-related morbidity and mortality worldwide. In recent years, the gut microbiota has gained increasing attention in CRC research. Intestinal microbes are not passive bystanders in tumor development. They may promote persistent inflammation, disrupt epithelial barrier integrity, alter microbial metabolites, and affect host immune and signaling pathways. Emerging evidence also suggests that microbiota-related metabolites and microbial functional alterations may influence host epigenetic regulation, including DNA methylation and chromatin-associated signaling, thereby further shaping colorectal carcinogenesis. Together, these changes can create a microenvironment that favors tumor initiation and progression. Several bacterial species, including Fusobacterium nucleatum, Parvimonas micra, and Peptostreptococcus anaerobius, have been repeatedly associated with CRC. In contrast, beneficial commensal microbes and their metabolites, especially short-chain fatty acids, may help maintain intestinal homeostasis and limit tumor-promoting processes. Because the gut microbiota is strongly shaped by diet, lifestyle, and environmental exposure, regional differences are also relevant. This is particularly important in Sichuan, China, where distinctive dietary habits and environmental features may influence microbial patterns associated with CRC risk and disease behavior. This review summarizes the main mechanisms linking the gut microbiota to CRC, examines the regional context of Sichuan, China, and discusses current and emerging clinical strategies. These include dietary intervention, probiotics, fecal microbiota transplantation, and microbiome-informed approaches to prevention, diagnosis, and treatment. Full article

Bergamot essential oil (BEO) has demonstrated antidepressant potential, but its oral application is limited by poor water solubility and undesirable organoleptic properties. In this study, a BEO-loaded beverage was developed based on a whey protein-stabilized oil-in-water emulsion system. The optimal formulation, determined via single-factor experiments combined with orthogonal optimization, consisted of inulin (0.5 g/50 g), milk powder (2.0 g/50 g), sucralose (0.008 g/50 g), and sodium carboxymethyl cellulose (0.04 g/50 g). The resulting beverage remained stable without visible phase separation during 4 months of storage at 4 °C. In a chronic corticosterone treatment (CCT)-induced mouse model of depression, oral administration of the BEO beverage increased activity in the central area of the open field test and exploratory behavior in the elevated plus maze, while reducing repetitive stereotyped behaviors in the marble burying test. At the molecular level, the BEO beverage was associated with reduced levels of interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and corticosteroid (CORT), and increased levels of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), serotonin (5-HT), dopamine (DA), and norepinephrine (NE). Additionally, the BEO beverage was associated with observed alleviation of neuronal damage in the hippocampal CA3 region, upregulation of brain-derived neurotrophic factor (BDNF), improved gut microbial diversity, and altered host metabolic profiles. Collectively, these findings suggest that the BEO emulsion beverage is a feasible intervention for alleviating depression-like behaviors in the mouse model, and provide initial associative evidence supporting its potential as a functional food for mood management. Full article

Growing evidence links gut microbiota dysbiosis to neurodegenerative diseases (NDs) such as Alzheimer’s disease and Parkinson’s disease, yet the field remains dominated by correlational observations rather than experimentally validated causal mechanisms. In this hypothesis-generating Perspective, we propose that causal inference in microbiota-associated neurodegeneration may be strengthened by combining two complementary lenses: evolutionary biomedicine and microbial metabolism. Because evolutionary information carries intrinsic temporal and causal structure, it can provide biological prior knowledge for inferring causal mechanisms of diseases. Human Accelerated Regions (HARs), genomic loci conserved across mammals but rapidly divergent in the human lineage, offer an anchor for identifying human-specific host–microbe co-evolutionary units relevant to NDs. We further hypothesize that microbial metabolites represent one class of mechanistically testable intermediates linking host genetic background, gut microbial ecology, and neurodegenerative phenotypes. This integrated evolutionary-metabolic perspective offers a tractable path from correlation toward mechanism in gut microbiota–ND research. Full article

To clarify the compositional characteristics and functional mechanisms of gut microbial communities in wild earwigs (Dermaptera) and explore the potential of earwigs for development and utilization as natural enemies, this study conducted a comparative analysis of the gut microbial diversity and community structure of two earwig species, Timomenus komarovi (Semenov, 1901) and Eudohrnia metallica (Dohrn, 1865), which are widely distributed in mulberry orchards and cornfields of Guizhou Province, China. It also predicted the microbial functions based on the third-generation high-throughput sequencing technology targeting the 16S rRNA gene. The results showed that the two earwig species across different habitats and geographical regions harbored a similar core microbial flora. The dominant phyla of gut microbiota were Proteobacteria, Firmicutes. PICRUSt2 functional prediction analysis revealed that the functions of intestinal bacteria in earwigs were mainly concentrated in metabolism-related pathways. Through multi-dimensional analysis, it was confirmed that the gut microbial communities of earwigs were constructed following the “core-specialization” model. The core microbial communities exhibited high conservatism. Host species were the core factor shaping the composition of earwig gut microbial communities. Habitats could further regulate the commonness and diversity characteristics of the microbial communities, while geographical regions had an extremely weak impact on the gut microbial communities. Significant differences were observed in the gut microbial adaptation strategies between the two earwig species, which determined their distinct development potential and application scenarios as natural enemy insects: T. komarovi is suitable for development as a broad-spectrum natural enemy, while E. metallica is more appropriate for targeted development based on its microbial community characteristics. All data supporting the findings of this study are accessible in the NCBI database under BioProject accession number PRJNA1449822. This study provides a theoretical basis for exploring the functional mechanisms of intestinal microbes in dermapteran insects and supporting the development and utilization of these natural enemy resources. Full article