Search Results (1,048)

Neutrophils are the most abundant circulating leukocytes and essential components of innate immunity. Through mechanisms such as phagocytosis, reactive oxygen species (ROS) production, degranulation, and neutrophil extracellular trap (NET) formation, they play a crucial role in host defense. However, dysregulated neutrophil responses are linked to chronic inflammatory conditions, including periodontitis. This review summarizes current evidence on neutrophil biology in periodontal health and disease, focusing on functional mechanisms, recruitment pathways, the influence of dysbiosis, and their potential as biomarkers and therapeutic targets. Neutrophils display a dual role in periodontal tissues: while protecting against microbial invasion, their excessive or impaired activity contributes to tissue destruction. Altered chemotaxis, defective phagocytosis, and uncontrolled NET release perpetuate inflammation and alveolar bone loss. Neutrophil-derived enzymes, including myeloperoxidase, elastase, and matrix metalloproteinases, emerge as promising biomarkers for early diagnosis. In parallel, therapeutic strategies targeting oxidative stress, NET regulation, or neutrophil hyperactivity are being explored to preserve periodontal tissues. Neutrophils are central players in periodontal pathophysiology. Understanding their regulation and interaction with the oral microbiome may enable the development of novel diagnostic and therapeutic approaches, ultimately improving periodontal disease management. Full article

Drought and salt stresses are critical environmental constraints affecting plant growth and development, and microorganisms can enhance plant tolerance to these abiotic stresses through complex mechanisms. This review systematically synthesizes the core mechanisms by which microorganisms regulate plant physiological and biochemical processes under such stresses, specifically including the following: (1) regulating the perception and transduction of abiotic stress signals to enhance plant adaptive responses; (2) boosting gene expression and protein synthesis for overall plant metabolic regulation; (3) activating the antioxidant system to strengthen plant tolerance; (4) modulating plant hormone levels to stimulate growth in response to adversity; (5) enhancing plant nutrition and absorption to improve resilience; (6) optimizing the photosynthesis system to promote the synthesis of essential substances, safeguarding plant growth and development amidst adversity. Finally, the application of microbial inoculants in saline–alkali soil improvement and crop cultivation in arid areas and prospective research directions are discussed. Full article

Nitric oxide (NO), a reactive nitrogen species (RNS), plays a role in multiple biological functions and signal transduction. However, the mechanisms by which NO counteracts stress tolerance in microbes have been poorly explored. In addition, the decomposition of salty food waste poses a significant challenge for food-degrading microbes. Therefore, we investigated how S-nitrosocysteine (CysNO) affects the cellular salt stress response of Burkholderia vietnamiensis TVV75, a strain isolated from a commercial food waste composite. Under the additional 2% NaCl treatment, increased reactive oxygen species (ROS) inhibited bacterial cell growth and viability. In contrast, CysNO treatment alleviated the cellular ROS levels and growth inhibition by augmenting the superoxide dismutase (SOD) and catalase (CAT) activities. CysNO supplementation also promotes the nitrate reduction pathway in B. vietnamiensis TVV75 under salt stress, suggesting NO-mediated nitrogen metabolism for microbial adaptation to salt stress. Furthermore, CysNO restored the intracellular lipid-degrading lipase enzyme activities, which were compromised by salt stress alone. This restoration was accompanied by a concentration-dependent increase in the relative expression of the lipA (lipase A) and ELFPP (esterase lipase family protein) genes. These results suggest that external NO supplementation can regulate redox balance, nitrate reduction, and lipase activity to maintain microbial cell growth in high-salt environments, pinpointing a NO-dependent salt stress adaptation strategy for salt-sensitive microbes involved in food waste decomposition. Full article

The interaction between the gut microbiota and the host immune system is pivotal in maintaining health or driving disease pathogenesis. The gut microbiota directly or indirectly modulates immune cells activation and inflammatory cytokines secretion through microbial metabolites, including short-chain fatty acids (SCFAs), tryptophan metabolites, bile acids, and polyamines. Conversely, the immune system regulates microbial community composition by maintaining the integrity of the epithelial barrier. In addition, antibiotics and probiotics can further regulate the inflammatory response by altering gut microbiota structure and microbial metabolites levels. This review systematically examines the bidirectional regulatory mechanisms among the gut microbiota, microbial metabolites, and inflammatory cytokines, and explores the impact of antibiotics and probiotics on this interaction network. These insights provide new targets for immune-related diseases. Full article

Biochar is increasingly recognized as a multifunctional soil amendment that improves soil fertility, nutrient cycling, and crop productivity. Studies across field, greenhouse, and incubation settings show that biochar enhances nutrient retention, reduces leaching, and regulates carbon, nitrogen, and phosphorus cycling. Its effects are shaped by intrinsic physicochemical properties and interactions with soil minerals, microbial communities, and enzymatic processes. Short-term benefits of biochar applications often include improved nutrient adsorption and water regulation, while long-term applications support stable soil organic matter formation, root development, and fertilizer use efficiency. Biochar also reshapes soil microbial diversity and activity. Beneficial bacterial groups such as Proteobacteria and Actinobacteria, along with fungi such as Mortierella, respond positively, enhancing nitrogen fixation, phosphorus solubilization, and organic matter decomposition. Meanwhile, biochar applications could suppress pathogens. Enzyme activities, including urease and phosphatase, are typically stimulated, driving nutrient mobilization. Yet outcomes remain context-dependent, with biochar feedstock, application rate, soil conditions, and crop type influencing results; excessive use may suppress enzymatic activity, reduce nutrient availability, or shift microbial communities unfavorably. Practically, biochar can improve fertilizer efficiency, restore degraded soils, and reduce greenhouse gas emissions, contributing to climate-smart agriculture. Future work should prioritize long-term, multi-site trials and advanced analytical tools to refine sustainable application strategies. Full article

Soyasaponin intolerance is common in ancient fish species, making them susceptible to enteritis caused by dietary soybean meal. β,β-Dimethylacrylshikonin is the key active monomer found in Lithospermum erythrorhizon and is known for its multiple pharmacological activities. However, its effect on soybean meal-induced enteritis remains unknown. The administration of 2 g/kg of β,β-Dimethylacrylshikonin (LE) effectively alleviated 5 g/kg of soyasaponin-induced histopathological changes and dysfunction, as evidenced by the expression of inflammation-related genes (il-1β, il-8, and il10). Regarding the gut microbiota composition, LE therapy decreased the population of inflammation-linked Proteobacteria and concurrently elevated the proportion of Fusobacteriota, effectively sustaining the balance of the zebrafish gut microbiota. Moreover, at the genus level, LE treatment also increased the abundance of Cetobacterium. Transcriptional results suggested that LE intervention mainly regulated immune-related pathways, including cytokine–cytokine receptor interaction, the TGF-beta signaling pathway, taurine and hypotaurine metabolism, and arachidonic acid metabolism. In conclusion, 5 g/kg of soyasaponins caused intestinal injury in zebrafish, and β,β-Dimethylacrylshikonin can reduce intestinal inflammation by regulating the intestinal microbial balance and metabolic disorder, with the best effect at 2 g/kg. Full article

Wax apple (Syzygium samarangense) is highly perishable postharvest. Even under refrigerated storage conditions, its shelf life typically lasts only about one week. This study developed a novel antibacterial food packaging membrane to extend its shelf life and explored the underlying preservation mechanisms. A composite fiber membrane was fabricated via solution blow spinning (SBS) using polyethylene oxide (PEO) and oxidized sesbania gum (OSG) incorporated with ε-polylysine (ε-PL). The composite membrane demonstrated exceptional antibacterial activity against both E. coli and S. aureus by disrupting cell wall and membrane integrity, as evidenced by increased protein leakage, alkaline phosphatase activity, and electrical conductivity. Morphological observations through scanning electron microscopy confirmed extensive cellular damage and bactericidal effects. During nine days of ambient storage, the PEO/OSG/PL membrane significantly maintained the postharvest quality of wax apples. This was evidenced by a lower decay index (2.22 ± 0.19) and weight loss rate (5.32 ± 0.16%) compared to the control group, alongside better preservation of firmness (4.11 ± 0.08 N) and color stability. The treatment suppressed respiratory rate and delayed the degradation of soluble solids and titratable acidity. Furthermore, it enhanced antioxidant capacity through higher peroxidase activity and reduced malondialdehyde accumulation, indicating attenuated oxidative stress. Non-targeted metabolomics analysis revealed that the membrane treatment modulated critical metabolic pathways, particularly phenylalanine metabolism and linoleic acid metabolism. These metabolic adjustments contributed to enhanced defense responses and delayed senescence. The results show that the PEO/OSG/ε-PL fiber membrane acts as an effective active packaging material by inhibiting microbial growth and regulating metabolism. This provides a potential method to extend the shelf life of perishable fruits. Full article

Primary sclerosing cholangitis (PSC) is a chronic, immune-mediated cholestatic liver disease characterized by progressive bile duct inflammation and fibrosis. Its strong association with inflammatory bowel disease (IBD) highlights the possible role of the gut–liver axis in disease pathogenesis. Here, we review the mechanisms that may contribute to the disruption of the gut–liver axis, leading to liver injury and the development of PSC. In particular, disruption of the intestinal barrier allows microbial products to enter the portal circulation, stimulating hepatic immune cells and triggering biliary inflammation. Concurrently, gut-primed lymphocytes expressing mucosal homing receptors migrate aberrantly to the liver, where they may contribute to biliary epithelial cell injury. Dysbiosis, characterized by reduced microbial diversity and the expansion of bile-tolerant and pro-inflammatory taxa, amplifies this immune activation and disturbs gut–liver homeostasis. Moreover, bile acids act as signaling molecules, regulating metabolism and immune responses through receptors such as FXR and TGR5. Dysregulation of these pathways may promote cholestasis, inflammation, and fibrosis. By understanding these interactions, we may identify novel therapeutic targets for PSC. Full article

Microbial fuel cell (MFC) is a novel and environmentally friendly technology for wastewater treatment and pollutant resource utilization. Although advances have been made in various aspects including electrode materials and synthetic biology approaches, the overall performance of MFC still requires improvement, with mass transfer efficiency and structural stability of biofilms emerging as key bottlenecks constraining their practical applications. This study investigated the regulation of substrate type and electrode potential during bioanode culture to optimize biofilm structure and enhance MFC performance. Results demonstrated that bioanodes cultured with glucose at −0.3 V formed vertically ordered biofilms that exhibited significant advantages in mass transfer characteristics, electrocatalytic activity, and structural stability. Under these culture conditions, enriched fermentative microorganisms facilitated the construction of porous biofilm scaffolds, while the electric field generated by the −0.3 V potential further induced vertical orientation and ordered arrangement of the biofilm. The superior mass transfer characteristics enabled the inner, middle, and outer layers of the biofilm to maintain high microbial activity (>50%), thereby maximizing the catalytic activity of electroactive microorganisms in each layer and enhancing biofilm structural stability. This study proposes a bioanode culture strategy centered on biofilm structural optimization, providing new theoretical foundations and technical pathways for achieving long-term stable and efficient MFC operation. Full article

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality worldwide. Although immune checkpoint inhibitors (ICIs) have achieved striking clinical efficacy in the subset of CRCs with mismatch repair deficiency/high microsatellite instability (dMMR/MSI-H), the vast majority of patients—those with proficient mismatch repair/microsatellite-stable (pMMR/MSS) tumors—derive little benefit from current immunotherapies. Ferroptosis, an iron-dependent form of regulated cell death driven by lethal accumulation of lipid peroxides, has emerged as a promising antitumor mechanism that can interact with and modulate antitumor immunity. Concurrently, the gut microbiota exerts powerful control over host metabolism and immune tone through microbial community structure and metabolite production; accumulating evidence indicates that microbiota-derived factors can either sensitize tumors to ferroptosis (for example, via short-chain fatty acids) or confer resistance (for example, indole-3-acrylic acid produced by Peptostreptococcus anaerobius acting through the AHR→ALDH1A3→FSP1/CoQ axis). In this review we synthesize mechanistic data linking microbial ecology, iron and lipid metabolism, and immune regulation to ferroptotic vulnerability in CRC. We discuss translational strategies to exploit this “microbiota–ferroptosis” axis—including precision microbiome modulation, dietary interventions, pharmacologic ferroptosis inducers, and tumor-targeted delivery systems—and we outline biomarker frameworks and trial designs to evaluate combinations with ICIs. We also highlight major challenges, such as interindividual microbiome variability, potential collateral harm to ferroptosis-sensitive immune cells, adaptive antioxidant compensation (e.g., NRF2/FSP1 activation), and safety/regulatory issues for live biotherapeutics. In summary, this review highlights that targeting the microbiota-ferroptosis axis may represent a rational and potentially transformative approach to reprogramming the tumor microenvironment and overcoming immune checkpoint resistance in pMMR/MSS colorectal cancer; however, further research is essential to validate this concept and address existing challenges. Full article

The gut microbiota, a complex community of trillions of microorganisms residing in the gastrointestinal tract, plays a vital role in maintaining host health and regulating a wide range of physiological functions. Advances in molecular biology have greatly expanded our understanding of the dynamic interactions between the gut microbiome and the immune system. Disruption of this microbial community, known as dysbiosis, can compromise epithelial barrier integrity, trigger aberrant immune activation, and lead to the production of proinflammatory metabolites. These changes are increasingly recognized as contributing factors in the pathogenesis of chronic inflammatory diseases. Emerging research highlights the gut microbiota as a key modulator of immune homeostasis, influencing both local and systemic inflammatory processes during the initiation and progression of these diseases. Understanding the mechanisms underlying gut microbiota-immune interactions will offer new avenues for therapeutic interventions. This review focuses on six representative chronic inflammatory diseases, including rheumatoid arthritis, inflammatory bowel disease, psoriasis, systemic lupus erythematosus, asthma, and vasculitis, all of which are characterized by dysregulated immune responses and persistent inflammation. Our goal is to synthesize the recent research on the role of gut microbiome in the pathogenesis of the diseases listed above and provide insights into the development of microbiota-based therapies, particularly fecal microbiota transplant, dietary modifications, prebiotic and probiotic interventions, for their treatment. Full article

The gut microbiota of Drosophila melanogaster offers a simplified yet powerful system to study conserved mechanisms of host–microbe interactions. Unlike the highly complex mammalian gut microbiota, which includes hundreds of species, the fly gut harbors a small and defined community dominated by Lactobacillus and Acetobacter. Despite its low diversity, this microbiota exerts profound effects on host physiology. Commensal bacteria modulate nutrient acquisition, regulate insulin/TOR signaling, and buffer dietary imbalances to support metabolic homeostasis and growth. They also influence neural and behavioral traits, including feeding preferences, mating, and aggression, through microbial metabolites and interactions with host signaling pathways. At the immune level, microbial molecules such as peptidoglycan, acetate, uracil, and cyclic dinucleotides activate conserved pathways including Imd, Toll, DUOX, and STING, balancing antimicrobial defense with tolerance to commensals. Dysbiosis disrupts this equilibrium, accelerating aging, impairing tissue repair, and contributing to tumorigenesis. Research in Drosophila demonstrates how a low-diversity microbiota can shape systemic host biology, offering mechanistic insights relevant to human health and disease. Full article

Background: Hyperuricemia (HUA), a metabolic disorder characterized by high serum uric acid (UA) level, presents a growing global health challenge. Method: In this study, a stable murine model of HUA was established by orally administering adenine (100 mg/kg) and potassium oxonate (600 mg/kg) in C57BL/6J mice, resulting in significant elevation of serum UA and xanthine oxidase (XOD) activity, as well as renal pathological alterations. Given the anti-hyperuricemia potential of Lactiplantibacillus plantarum WLPL04, a strain from a human breast milk was evaluated. Conclusions: Oral administration of L. plantarum WLPL04 significantly reduced serum UA level and XOD activity in a dose-dependent manner. Moreover, L. plantarum WLPL04 treatment enhanced UA excretion by upregulating ABCG2 and downregulating URAT1 and GLUT9 expression. It ameliorated renal injury and suppressed inflammation via downregulation of the NLRP3 inflammasome pathway. 16S rRNA gene sequencing revealed that L. plantarum WLPL04 restored gut microbial diversity and promoted the enrichment of beneficial genera such as Bacteroides, which was negatively correlated with UA in serum, creatinine, and inflammatory cytokines. Moreover, transcript analysis revealed upregulation of purine salvage genes (hpt and xpt), suggesting enhanced salvage pathway recycling of purine bases and reduced urate production. Those findings suggest that L. plantarum WLPL04 exerted multi-targeted anti-hyperuricemia effects through coordinated regulation of host purine metabolism, urate transport, inflammation, and gut microbiota composition, providing a promising probiotic candidate for HUA management. Full article

Overweight, including its severe form obesity, among children and adolescents has risen rapidly in Latin America. Schools play a critical role in addressing this growing public health challenge, as they offer a structured setting to implement preventive interventions targeting nutrition literacy, physical activity, and the food environment. The aim of this article is to describe the effectiveness of school-based interventions for preventing overweight in Latin America and whether existing policies, programs and other initiatives in the region align with the best available evidence. Among the 27 interventions included, most were conducted in Chile (41%), used a pre–post design (41%), adopted a preventive approach (85%), and reported positive effects (52%). Effective interventions included activities on nutrition literacy, physical activity, nutritious foods and diets, provision of free and safe drinking water (e.g., water that is free from microbial contamination and suitable for drinking), and healthy food environment. Experimental studies showed that the duration of effective interventions ranged from two months to two years and were primarily directed at primary school students including parents and teachers. Argentina, Chile, Colombia, Mexico, Peru, and Uruguay had multi-component policies and programs under a regulatory framework (e.g., laws or regulations passed by a government) based on the best available evidence to prevent overweight in school-aged children and adolescents. Only a limited number of countries have implemented these interventions. Ensuring program sustainability is critical to inform evidence-based childhood overweight prevention policies in the region. Policymakers should use the best scientific evidence to guide childhood overweight prevention strategies. Full article

Biochar amendment has been widely recognized for its potential to promote soil carbon sequestration and improve crop productivity; however, the microbial mechanisms underlying carbon sequestration at varying biochar application rates remain insufficiently understood. In this study, a field experiment was conducted in a typical fluvo-aquic soil region of the North China Plain under a maize–wheat rotation, with one-time biochar application at four levels: CK (0 t ha⁻¹), B5 (5 t ha⁻¹), B10 (10 t ha⁻¹), and B20 (20 t ha⁻¹). The effects of these treatments on soil physicochemical properties, organic carbon fractions, microbial community structure, and enzyme activities were systematically examined. The results showed that soil total nitrogen (TN) and pH increased consistently with higher biochar application rates, reaching maximum values under B20 treatment, where TN and pH rose by 35.56% and 7.00% relative to CK, respectively. In contrast, the contents of NH₄⁺-N, available phosphorus (AP), and available potassium were mostly enhanced under B5 during the maize season, while in the wheat season, NH₄⁺-N peaked under B10 and AP peaked under B5. Biochar addition significantly increased soil organic carbon fractions and the carbon pool management index (CMI). In the maize season, soil organic carbon (SOC), microbial biomass carbon (MBC), particulate organic carbon (POC), and CMI under B20 rose by 55.99%, 39.67%, 79.69% and 180.54% over CK, respectively, whereas dissolved organic carbon (DOC) peaked under B5. Throughout the wheat season, SOC, MBC, and POC contents under B20 were 53.70%, 64.31% and 147.81% higher than CK, while DOC peaked under B5 (+56.98%). Soil enzyme activities, including catalase, urease, invertase and alkaline phosphatase, were strongly stimulated by biochar, with B20 increasing their activities by 4.49–18.18%, 3.19–19.77%, 6.14–26.14% and 12.25–33.19%, respectively. Biochar also reshaped microbial community structure: the during maize season, it reduced the relative abundance of Glomeromycetes (65.31%) and Oligohymenophorea (51.64%) while enhancing Deltaproteobacteria (46.15%) and Gammaproteobacteria (29.03%); during wheat season; it enhanced Eurotiomycetes (85.77%) and Dothideomycetes (16.28%) but suppressed Deinococci (74.08%) and Alphaproteobacteria (4.39%). Pathway analysis further indicated that biochar amendments indirectly increased SOC fractions and CMI by simultaneously altering nutrient availability, regulating microbial community structure, and stimulating soil enzyme activities. Collectively, these findings highlight that the effects of biochar are dosage-specific: moderate rates (e.g., 5 t ha ⁻¹) are more suitable for the short-term improvement of soil fertility, while higher rates (e.g., 20 t ha⁻¹) are more effective for long-term carbon sequestration; depending on the objective, biochar application can thus substantially modify soil physicochemical and biological processes to promote agroecosystem sustainability in the North China Plain. Full article