Search Results (473)

Stainless steel (SS) remains widely used in orthopedic implants but is susceptible to corrosion and implant-associated infections in physiological environments. This study aimed to develop a multifunctional multilayer coating combining corrosion resistance, bioactivity, and antimicrobial performance. A ZnO base layer was deposited on 316L SS via pulsed laser deposition, followed by matrix-assisted pulsed laser evaporation of a lovastatin-functionalized bioactive glass (BG57 + LOV) top layer. Two LOV concentrations were initially evaluated, and BG57+0.1LOV was selected based on structural homogeneity, cytocompatibility, and antimicrobial balance. Physicochemical characterization confirmed preservation of chemical integrity and formation of continuous, moderately rough coatings. Electrochemical impedance spectroscopy in simulated body fluid demonstrated progressive improvement in corrosion resistance from bare SS to ZnO-coated and finally to the BG57+0.1LOV/ZnO multilayer, which exhibited the most electropositive corrosion potential and effective suppression of charge-transfer reactions. Biological assays revealed high viability of osteoblasts, fibroblasts, keratinocytes, and macrophages without significant oxidative or nitrosative stress. Antimicrobial testing showed strain-dependent activity, with enhanced efficacy against MRSA and significant reduction in P. aeruginosa, associated with increased ROS/RNS generation. Overall, the BG57+0.1LOV/ZnO system represents a promising multifunctional coating strategy for corrosion-resistant and infection-resistant SS implants. Full article

The crosstalk between the endocannabinoid system (ECS) and reactive nitrogen species (RNS) has emerged as an important area of investigation in recent years. Although many aspects of this interaction remain elusive, accumulating evidence demonstrates that the ECS plays a critical role in regulating RNS-mediated signaling under physiological conditions. This modulation can be either inhibitory or stimulatory, depending on the specific receptor subtype, cell type, and tissue location involved. While ECS-RNS interactions support normal cellular homeostasis, their dysregulation contributes to various disease states, particularly neurodegenerative disorders. Studies in both rodent models and human subjects show that ECS modulation can reduce anxiety, attenuate neuroinflammatory responses, and slow disease progression in neurodegenerative conditions. This review examines how cannabinoid-based interventions modulate nitrosative stress and neuroinflammation in Alzheimer’s disease (AD) and Parkinson’s disease (PD), highlighting their potential as targeted therapeutics that address multiple pathological mechanisms simultaneously and may offer advantages over conventional treatment approaches. Full article

Ionizing radiation (IR) exposure poses a significant biomedical challenge in clinical, occupational, and emergency contexts, highlighting the urgent need for effective medical countermeasures against acute radiation syndrome (ARS) and delayed effects of radiation exposure (DEARE). Depending on the timing of administration, radiation countermeasures are classified as radioprotectors, radiomitigators, or therapeutics. Among these, radiomitigators offer a critical advantage by attenuating IR-induced damage when administered after exposure, thereby expanding their applicability in unanticipated radiation incidents. This review provides an overview of the pathophysiological mechanisms underlying IR-induced injury and summarizes the current FDA-approved radiation countermeasures. It then focuses on radiomitigators that have demonstrated efficacy in preclinical animal models, together with available evidence from clinical studies, emphasizing their translational potential for both emergency preparedness and oncological settings. We examine routes of administration and key mechanisms of action, including modulation of oxidative and nitrosative stress, enhancement of DNA damage response pathways, preservation of mitochondrial function, regulation of inflammatory and immune signaling, attenuation of fibrotic remodeling, maintenance of vascular integrity, and promotion of tissue regeneration and repair. Finally, challenges associated with clinical translation and strategies to optimize radiomitigators for the management of radiation-induced injury are discussed. By integrating these insights and consolidating existing knowledge, this review aims to guide basic and clinical research toward more effective radiomitigative strategies and combination therapies to improve survival, limit tissue damage, and preserve long-term quality of life in individuals exposed to IR. Full article

Background: Silicosis is a progressive fibrotic lung disease caused by chronic inhalation of crystalline silica. Increasing evidence indicates that oxidative stress plays a central role in linking silica exposure to inflammation, tissue injury, and fibrosis. We conducted a systematic review to critically appraise the current evidence on the imbalance between oxidant and antioxidant markers in patients with silicosis compared with unexposed healthy controls. Methods: A systematic literature search was conducted in PubMed, Scopus, and Google Scholar from their inception to 30 November 2025. Eligible studies assessed oxidative stress biomarkers in biological samples from patients with silicosis and non-exposed controls. Results: Malondialdehyde (MDA) and Superoxide Dismutase (SOD) were the most frequently assessed oxidative and antioxidant markers, respectively, with MDA significantly increased and SOD decreased in patients with silicosis, highlighting amplified lipid peroxidation and impaired antioxidant defense. In addition, elevated levels of other oxidant molecules confirmed the presence of lipid, nitrosative, and DNA oxidative damage. Overall, antioxidant defenses were compromised, although some markers appeared to vary with disease stage. Conclusions: This review highlights the central role of oxidative stress in the pathogenesis and progression of silicosis. Future studies with larger cohorts and a broader range of biomarkers are needed to better understand oxidative imbalance and its potential utility for monitoring disease progression and assessing severity in this population. Full article

Food allergies are increasing worldwide, yet the early epithelial mechanisms that initiate allergic sensitization remain incompletely defined. As the intestinal epithelium governs both allergen translocation and epithelial–immune crosstalk, it constitutes a critical but underutilized model for predicting allergenicity. In this study, we used Caco-2 and T84 intestinal epithelial monolayers cultured on Transwell^® inserts to compare barrier properties and responses to peanut protein extract. Phenotypic characterization included biomarker profiling, transepithelial electrical resistance (TEER) measurements, tight junction integrity assessment, and analysis of cytokine levels as well as oxidative and nitrosative stress. Peanut exposure caused moderate TEER reductions without overt tight junction disruption while allowing translocation of the major allergen, Arachis hypogaea allergen 1 (Ara h 1), likely via transcellular pathways. Peanut protein extracts also induced epithelial stress responses, characterized by increased reactive oxygen species and nitric oxide production, alongside time-dependent secretion of innate and type 2-associated mediators, including IL-1β, TSLP, IL-25, and IL-33, indicating epithelial activation in the absence of complete barrier breakdown. Notably, basolateral supernatants from peanut-exposed epithelial monolayers activated THP-1-derived macrophages and enhanced IL-6 secretion, demonstrating that limited allergen passage across an otherwise intact epithelial barrier is sufficient to elicit early innate immune responses. Collectively, these findings indicate that peanut extract induce subtle functional perturbations in the intestinal epithelium while promoting downstream immune activation, highlighting Caco-2 and T84 cells as complementary in vitro platforms for studying barrier-dependent mechanisms of allergic sensitization. Full article

Introduction: cigarette smoking is a major source of systemic oxidative stress and a well-established risk factor for cardiovascular disease. Heated tobacco products (HTPs) are increasingly promoted as reduced-risk alternatives, yet their cellular effects remain incompletely understood. Methods: this study compared the oxidative stress-mediated effects of conventional cigarette smoking and HTP use on human erythrocytes. Erythrocytes from healthy non-smokers, conventional smokers, and HTP users were analyzed using biochemical, functional, and cytological approaches to assess redox status, membrane and cytoskeletal organization, anion exchanger 1 (AE1) function, antioxidant response, and redox-sensitive signaling pathways. Results: conventional smokers exhibited higher intracellular reactive oxygen species (ROS) levels, thiol depletion, methemoglobin and hemichrome formation, whereas HTP users showed marked lipid peroxidation despite lower ROS availability. Both groups instead displayed altered expression and distribution of key membrane and cytoskeletal proteins, including glycophorin A, AE1, spectrin, ankyrin, and band 4.1, indicating impaired membrane–cytoskeleton interactions. Functional analyses revealed an accelerated AE1-mediated anion exchange in erythrocytes from conventional smokers, whereas cells from HTP users exhibited a reduced sulfate accumulation, indicating altered transport capacity. In both groups, G6PDH activity was significantly increased, and redox-sensitive signaling pathways involving ERK, AKT, and eNOS were activated, accompanied by sex-dependent alterations in estrogen receptor expression and distribution. Conclusions: collectively, these findings identify erythrocytes as sensitive biomarkers of tobacco-related systemic damage and indicate that smoking-induced erythrocyte dysfunction, including that associated with HTP use, may actively contribute to vascular impairment. This evidence challenges the assumption that heated tobacco products confer a substantially reduced cardiovascular risk compared with conventional cigarettes. Full article

Intestinal ischemia–reperfusion injury (IRI) represents a major cause of morbidity and mortality in abdominal surgery, trauma, and intestinal transplantation. The pathophysiological process involves a biphasic cascade that begins with ischemic hypoxia and progresses to amplified cellular and molecular injury upon reperfusion. This review synthesizes recent mechanistic insights regarding endothelial and microvascular dysfunction, epithelial barrier breakdown, microbiota-driven systemic propagation, and the involvement of oxidative/nitrosative stress and inflammatory signaling. The novelty of our review’s approach is the focus on experimental and translational studies and correlation of the data with future directions for mechanistic research and clinical implementation. Despite promising preclinical results, heterogeneity in study protocols or/and model limitations make clinical translation challenging. Recent studies have demonstrated that mitochondria, tight junction proteins, adhesion molecules and innate immune receptors are critical determinants of lesion evolution. Based on these, the current therapeutic strategies include antioxidants, adenosine pathway modulators, dexmedetomidine, ischemic conditioning, hyperbaric oxygen therapy, and microbiota-targeted interventions. Since each mechanism is acting on distinct molecular pathways, a multimodal therapy that integrates redox modulation, endothelial protection, microbiome regulation, and the identification and employment of precision biomarkers is likely to improve outcomes. Beyond summarizing established molecular mechanisms, this review critically reassesses why decades of promising experimental strategies for intestinal ischemia–reperfusion injury has largely failed to translate into effective clinical therapies. By distinguishing context-dependent mechanisms from pathways with consistent translational relevance, we highlight key methodological and biological barriers limiting clinical applicability. Furthermore, we propose a temporally structured, multimodal therapeutic framework that integrates phase-specific pathophysiology with targeted interventions, aiming to inform future experimental design and improve translational success. Full article

Viral infections have been implicated in psychiatric outcomes through immune-mediated pathways. This 12-month prospective cohort study, designed as a pilot and hypothesis-generating investigation, compared psychiatric symptoms and inflammatory cytokine profiles in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), hepatitis C virus (HCV), and tick-borne encephalitis virus (TBEV), and explored their potential predictive value. Thirty-seven patients hospitalized with viral infections and 32 healthy controls were evaluated, acknowledging the limited sample size. Psychiatric interviews and the Hospital Anxiety and Depression Scale (HADS) were used for assessment. The study was divided into two stages. In Stage 1, during the acute infection, a psychiatric assessment was conducted, and cytokine levels were measured in the patients’ blood. In Stage 2, one year later, the psychiatric assessment was repeated. No significant differences were found in psychiatric diagnosis rates or symptom severity between infection groups, regardless of viral type or neuroinvasive capacity. However, these findings should be interpreted as preliminary given the limited sample size. Some cytokines, eg., interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), and soluble interleukin-2 receptor subunit alpha (sIL-2Rα), showed associations with individual symptoms, but these were inconsistent and did not demonstrate robust predictive value. Cluster analysis identified two distinct inflammatory profiles—one characterized by higher cytokine levels (predominantly in Coronavirus disease 2019 (COVID-19) and TBEV cases) and the other by lower cytokine levels (mostly in HCV and controls). However, different cytokine profiles did not correspond to clinical outcomes. The results suggest that psychiatric sequelae after viral infections are not directly driven by specific cytokines or infection type but rather emerge from a complex interaction of immune, psychological, and environmental factors. Single cytokine measurement is insufficient and cannot be used as a tool for assessing the risk of developing psychiatric disorders. Given the exploratory nature of the study, all results require confirmation in larger, adequately powered cohorts. Future studies should focus on composite biomarkers and systems-based models such as neuroimmune-metabolic-oxidative pathways (NIMETOX), or Immune-Inflammatory Response System (IRS)/Compensatory Immune Response System (CIRS)/Oxidative & Nitrosative Stress (O&NS) for improved predictive accuracy. Full article

Oxidative and nitrosative stress are key contributors to the development and progression of chronic inflammatory disorders, cancer and neurodegenerative diseases (viz., Alzheimer’s disease). Cholinergic dysfunction is a major hallmark of Alzheimer’s disease and is closely associated with these processes. Red seaweeds are rich in bioactive compounds that have been increasingly investigated for their potential to modulate these processes. This review aims to examine the role of major red seaweed-derived metabolites in regulating redox imbalance, immunomodulatory capacity and acetylcholinesterase activity, with emphasis on in vitro studies. An analysis of peer-reviewed literature was conducted, focusing on chemical, biochemical and cell-based assays. Studies assessed antioxidant activity, anti-inflammatory and immunostimulatory effects, and acetylcholinesterase inhibition of isolated compounds/fractions of red seaweed using established methods, including radical scavenging assays, Griess-based nitrite assay and enzyme inhibition assays. Sulfated polysaccharides, oligosaccharides, mycosporine-like amino acids (MAAs), phycoerythrin, bromophenols, phlorotannin and terpenoid-derived metabolites demonstrated antioxidant capacity through radical scavenging, metal chelation and modulation of endogenous antioxidants. They also modulated inflammatory mediators, including nitric oxide and pro-inflammatory cytokines, and inhibited acetylcholinesterase (AChE) activity. In vitro evidence supports red seaweed-derived compounds as promising modulators of redox homeostasis, inflammation and cholinergic function, highlighting their relevance as functional food ingredients, while underscoring the need for in vivo and clinical validation. Full article

Oxidative and nitrosative stress are central mechanisms in the pathogenesis of neurodegenerative diseases, where excessive production of reactive oxygen and nitrogen species (ROS/RNS) leads to mitochondrial dysfunction, membrane damage, and neuronal death. In this study, we established and compared short-term (2 h) and long-term (20 h) exposure paradigms to sodium nitroprusside (SNP), used as a xenobiotic nitric oxide donor, in two neuronal cell lines (mHippoE-18 and PC12) and zebrafish larvae, aiming to provide a preclinical framework for neurodegenerative drug discovery. In vitro, SNP exposure caused concentration-dependent reductions in viability and alterations in oxidative balance, with mHippoE-18 cells exhibiting higher susceptibility than PC12 cells. In the short-term exposure paradigm, cytotoxicity was primarily associated with membrane disruption at higher concentrations, whereas oxidative stress contributed more strongly at intermediate doses. In the long-term exposure, mHippoE-18 cells showed strong integrated correlations between ROS, LDH release, and viability loss, highlighting their increased vulnerability to nitrosative stress. In zebrafish, SNP exposure impaired metabolic activity and swimming behavior in both paradigms. Long-term exposure led to consistent dose-dependent increases in ROS, accompanied by locomotor deficits tightly linked to energy metabolism. Overall, the higher sensitivity of mHippoE-18 cells compared with PC12 cells, together with the dose-dependent metabolic and behavioral impairments observed in zebrafish, indicates that cellular responses partially mirror in vivo outcomes. This integrative approach underscores the value of combining neuronal cell lines with zebrafish larvae to capture complementary aspects of SNP-induced neurotoxicity and to strengthen preclinical evaluation of candidate compounds with protective or therapeutic potential. These findings support the use of SNP as a xenobiotic model to probe nitrosative stress-driven neurotoxicity across cellular and organismal systems. Full article

Background/Objectives: Larix decidua has been used in traditional medicine for the treatment of various inflammatory conditions. Although their use has been recognized in alternative medicine, the scientific documentation of the antioxidant and anti-inflammatory potential of ethanolic extracts from its needles remains insufficiently characterized. The present study aimed to characterize the phytochemical profile of the ethanolic L. decidua extract, evaluate its in vitro antioxidant capacity, and investigate its therapeutic and prophylactic effects on oxidative–nitrosative stress and inflammation. Methods: L. decidua needles were extracted using a modified Squibb repercolation method. Polyphenol and flavonoid content were quantified, and individual phenols were identified by HPLC-DAD-ESI⁺. The in vitro antioxidant activity was evaluated using DPPH, FRAP, H₂O₂, and NO scavenging assays. The therapeutic and prophylactic in vivo potential was evaluated in a model of acute inflammation induced with turpentine in male Wistar rats. Serum oxidative markers (TOS, TAC, OSI, MDA, AOPP, 8-OHdG, NO, 3-NT, SH) and inflammatory markers (NFκB-p65, IL-1β, IL-18) were quantified. Results: The extract contained high levels of flavonols and hydroxybenzoic acids; kaempferol glycosides and catechin were the dominant constituents. In vitro, the extract exhibited radical scavenging activities. In vivo, L. decidua attenuated oxidative and nitrosative stress, restored antioxidant defense, and reduced NFκB-p65, IL-1β, and IL-18 levels in a concentration-dependent manner. The L100 concentration most closely approximated the values produced by Trolox and diclofenac. Conclusions: The ethanolic Larix decidua needle extract exerted antioxidant and anti-inflammatory effects in a rat model of acute sterile inflammation, attenuating systemic oxidative–nitrosative stress and pro-inflammatory mediators in a concentration-dependent manner. These preclinical findings support further investigation of standardized L. decidua needle preparations as polyphenol-rich nutraceutical/functional ingredient candidates within preventive and adjunct nutrition strategies targeting oxidative stress-driven inflammation. Full article

Neurodegenerative disorders such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS) share key molecular features, including neuroinflammation, oxidative stress, mitochondrial dysfunction, and progressive neuronal loss. Increasing evidence indicates that gut dysbiosis and alterations in microbiota-derived metabolites are involved in these processes through multiple pathways along the gut–brain axis. However, while broad compositional changes are well-documented, a critical knowledge gap remains regarding the specific biochemical signal transduction pathways translating dysbiosis into pathology. This narrative review addresses this gap by synthesizing current human and experimental studies addressing gut microbiota alterations in AD, PD, and ALS, with particular emphasis on the biochemical and molecular mechanisms mediated by gut-derived metabolites. Dysbiosis in neurodegenerative diseases is frequently associated with reduced abundance of short-chain fatty acid (SCFA)-producing bacteria and altered metabolism of SCFAs, bile acids, tryptophan-derived indoles, trimethylamine-N-oxide (TMAO), and lipopolysaccharides (LPS). These microbial metabolites have been shown to modulate intestinal and blood–brain barrier integrity, influence Toll-like receptor- and G protein-coupled receptor-dependent signaling, regulate microglial activation, and affect molecular pathways related to protein aggregation in experimental models. In addition, emerging evidence highlights the involvement of oxidative and nitrosative stress, immune–metabolic crosstalk, and altered xenobiotic metabolism in microbiota–host interactions during neurodegeneration. By integrating microbiological, metabolic, and molecular perspectives, this review underscores the important and emerging role of microbiota-derived molecules in neurodegenerative disorders and outlines key chemical and metabolic pathways that may represent targets for future mechanistic studies and therapeutic strategies. Full article

Background: Due to chronic venous insufficiency, venous leg ulcers (VLUs) develop as chronic wounds characterized by impaired healing, persistent inflammation, and endothelial dysfunction. Nitrosative stress, mitochondrial damage, and tissue apoptosis caused by excess nitric oxide (NO) produced by iNOS in macrophages and fibroblasts are contributing factors in the chronic wound environment; therefore, pharmacological modulation of iNOS presents an attractive mechanistic target in chronic wound pathophysiology. Methods: Herein, we present the use of a structure-based computational strategy to assess the inhibition of tavaborole, a boron-based antifungal agent, against iNOS using human iNOS crystal structure (PDB ID: iNOS) by molecular docking using AutoDock 4.2, 500 ns simulation of molecular dynamics (MD), with equilibration within ~50 ns and analyses over full trajectory and binding free energy calculations through the MM-PBSA approach. Results: Docking studies showed favorable binding of tavaborole (–6.1 kcal/mol) in the catalytic domain, which stabilizes contacts with several key residues (CYS200, PRO350, PHE369, GLY371, TRP372, TYR373, and GLU377). MD trajectories for 1 ns showed stable structural configurations with negligible deviations (RMSD ≈ 0.44 ± 0.10 nm) and hydrogen bonding, and MM-PBSA analysis confirmed energetically favorable complex formation (ΔG_binding ≈ 18.38 ± 63.24 kJ/mol) similar to the control systems (L-arginine and 1400W). Conclusions: Taken together, these computational findings indicate that tavaborole can stably occupy the iNOS active site and interact with key catalytic residues, providing a mechanistic basis for further in vitro and ex vivo validation of its potential as an iNOS inhibitor to reduce nitrosative stress and restore endothelial homeostasis in venous leg ulcers, rather than direct therapeutic proof. Full article

Juniperus communis L. is a conifer widely used in traditional European medicine for the management of inflammatory disorders. However, its effects on oxidative stress and inflammation remain incompletely characterized. The present study investigated the antioxidant and anti-inflammatory potential of an ethanolic needle extract of J. communis using in vitro assays and an in vivo model of acute inflammation induced by turpentine oil in rats. Phytochemical profiling by HPLC–DAD–ESI–MS revealed a polyphenol-rich extract dominated by flavonols, flavanols, and hydroxybenzoic acids, with quercetin derivatives and taxifolin as major constituents. In vitro analyses demonstrated radical-scavenging and reducing capacities, exceeding or comparable to reference antioxidants in DPPH, hydrogen peroxide, ferric-reducing, and nitric oxide scavenging assays. In vivo, both therapeutic and prophylactic administration of the extract significantly attenuated oxidative and nitrosative stress, as evidenced by reductions in total oxidant status, oxidative stress index, malondialdehyde, advanced oxidation protein products, nitric oxide, 3-nitrotyrosine, and 8-hydroxy-2′-deoxyguanosine, alongside restoration of total antioxidant capacity and thiol levels. These effects were concentration-dependent. Concomitantly, inflammatory signaling was suppressed, with decreased NF-κB activity and reduced levels of interleukin-1β and interleukin-18. These results support the use of these extracts, whose benefits have been observed in traditional medicine, providing scientific support for the anti-inflammatory and antioxidant capacity of J. communis extract. Full article

Topical antibiotics have long been used for the prevention and treatment of superficial skin and soft tissue infections; however, increasing evidence indicates that their clinical value is undermined by rising antimicrobial resistance, high rates of allergic sensitization, inadequate activity against biofilms, and a lack of wound-healing properties. Agents such as bacitracin, neomycin, polymyxin B, mupirocin, and fusidic acid act through narrow, target-specific mechanisms that facilitate resistance selection and provide limited benefit in chronic or polymicrobial wound environments. Contemporary antimicrobial stewardship frameworks therefore discourage routine use of topical antibiotics and increasingly favor non-antibiotic antiseptics with broad-spectrum activity and low resistance risk, including silver, iodine, polyhexamethylene biguanide, octenidine, and medical-grade honey. These modalities, however, primarily serve to reduce microbial burden and do not directly address the underlying biological impairments that prevent healing. Nitric oxide-releasing gels (NORGs) represent a novel class of topical antimicrobials that combine multi-target bactericidal activity with physiologic pro-healing effects. Nitric oxide exerts potent antimicrobial and antibiofilm effects via oxidative and nitrosative stress, disruption of metabolic pathways, inhibition of DNA replication, and interference with quorum sensing. Simultaneously, nitric oxide enhances angiogenesis, modulates inflammation, improves microvascular perfusion, and promotes fibroblast and keratinocyte function. Preclinical models and early-phase clinical studies demonstrate broad-spectrum efficacy—including activity against multidrug-resistant organisms—with favorable tolerability and minimal risk of resistance development. Although the current evidence base remains preliminary, NORGs offer a promising antimicrobial platform with the potential to reduce reliance on topical antibiotics while simultaneously addressing key barriers to wound healing. Larger randomized controlled trials, direct comparisons with established advanced dressings, and robust pharmacoeconomic evaluations are needed to define their optimal role within stewardship-aligned wound-care practice. Full article