Search Results (270)

The anodic oxide layer’s porosity is considered a functional feature, acting as a reservoir of lubricants. This feature enables the design of self-lubricating systems that effectively reduce friction and wear. To improve the tribological performance of Al₂O₃ anodic coatings on EN AW 5251 aluminium alloys, this paper presents a modification of the coating with tungsten disulfide (IF-WS₂) nanopowder and its effect on coating resistance. The wear properties of Al₂O₃/IF-WS₂ coatings in contact with a cast iron pin were investigated. The results include the analysis of the friction coefficient in the reciprocating motion without oil lubrication at two loads, the analysis of the wear intensity of the cast iron pin, the characterisation of wear scars, and the analysis of SGP parameters. Two-level factorial analysis showed that load and nanomodification significantly affected the load-bearing parameter Rk. Incorporation of the modifier, especially under higher loads, reduced the Rk value, thus improving the tribological durability of the contact pair. Both load and nanomodification had a notable impact on the coefficient of friction. The use of IF-WS₂-modified coatings reduced the coefficient, and higher loads further enhanced this effect, by approximately 9% at a load of 0.3 MPa and 15% at a load of 0.6 MPa, indicating improved lubricating conditions under greater contact stress. Full article

Background/Objectives: Colorectal cancer (CRC) is among the most prevalent malignant neoplasms globally. Chemotherapeutic treatment strategies have demonstrated minimal improvement over the past decade. Combination therapies, including those with nutraceuticals, are currently being investigated as promising alternatives to enhance therapeutic efficacy. The organosulfur garlic extract diallyl disulfide (DADS) has demonstrated anti-tumoral activity in several types of cancer. This study aimed to investigate the effects of DADS and 5-fluorouracil (5-FU), both individually and in combination, on the human CRC cell lines Caco-2 and HT-29. Methods: Caco-2, HT-29, and non-tumoral human umbilical vein endothelial cells (HUVEC) were exposed to DADS (25–600 µM) and 5-FU (5–100 µM), either individually or in simultaneous combination (DADS 100 µM + 5-FU 100 µM), for 24 h. Cytotoxicity was evaluated in all three cell lines. In addition, the effects of these treatments on oxidative stress, cell migration, genotoxicity, cell death, global DNA methylation, and gene–nutraceutical interactions were assessed in both tumor cell lines. Results: DADS demonstrated cytotoxic effects at high concentrations in Caco-2, HT-29, and HUVECs and induced DNA damage in both colorectal cancer cell lines. The combination of DADS and 5-FU significantly promoted apoptotic cell death, increased genotoxicity, elevated global DNA methylation, and inhibited cell migration, with these effects being particularly pronounced in HT-29 cells. Conclusions: We provide evidence that DADS combined with 5-FU is potentially useful in the therapy of CRC. However the combination of nutraceuticals and chemotherapy must consider the distinct molecular and phenotypic characteristics of each tumor cell line. Full article

Redox signaling is central to plant adaptation, influencing metabolic regulation, stress responses, and developmental processes through thiol-based oxidative post-translational modifications (oxiPTMs) of redox-sensitive proteins. These modifications, particularly those involving cysteine (Cys) residues, act as molecular switches that alter protein function, structure, and interactions. Advances in mass spectrometry-based redox proteomics have greatly enhanced the identification and quantification of oxiPTMs, enabling a more refined understanding of redox dynamics in plant cells. In parallel, the emergence of computational modeling, artificial intelligence (AI), and machine learning (ML) has revolutionized the ability to predict redox-sensitive residues and characterize redox-dependent signaling networks. This review provides a comprehensive synthesis of methodological advancements in redox proteomics, including enrichment strategies, quantification techniques, and real-time redox sensing technologies. It also explores the integration of computational tools for predicting S-nitrosation, sulfenylation, S-glutathionylation, persulfidation, and disulfide bond formation, highlighting key models such as CysQuant, BiGRUD-SA, DLF-Sul, and Plant PTM Viewer. Furthermore, the functional significance of redox modifications is examined in plant development, seed germination, fruit ripening, and pathogen responses. By bridging experimental proteomics with AI-driven prediction platforms, this review underscores the future potential of integrated redox systems biology and emphasizes the importance of validating computational predictions, through experimental proteomics, for enhancing crop resilience, metabolic efficiency, and precision agriculture under climate variability. Full article

Silkworms synthesize and secrete silk to produce cocoons, which are excellent materials for textile and biomaterial manufacturing applications. However, the gene regulation associated with the post-translational modification of silk proteins remains unknown. In this study, we analyzed the physicochemical properties, evolutionary relationships, and expression patterns of BmPDI in silkworms. Subsequently, we knocked out BmPDI (BmPDI-KO), resulting in significant phenotypes of BmPDI-KO silkworms with smaller silk glands and cocoons, weaker silk mechanical properties, and reduced disulfide bonds in silk-associated proteins. Transcription levels of silk protein-related genes and unfolded protein response signal pathway-related genes were significantly downregulated. In contrast, genes involved in the apoptosis pathway were significantly upregulated in BmPDI-KO silkworms. Knocking out BmPDI in silkworms affected the post-translational modifications of the silk proteins, thereby accumulating misfolded silk proteins and hindering their secretion into the extracellular cells. This further increased endoplasmic reticulum stress, activated the apoptotic pathway, accelerated silk gland cell apoptosis, and significantly reduced the silk yields and mechanical properties of BmPDI-KO silkworm. This study provides a potential exploration of BmPDI in the modification of silk yields and mechanical properties of Bombyx mori. Full article

This study systematically investigates how thiol–disulfide interactions influence the structure and mechanical properties of casein gels. Acid gels were prepared from suspensions of micellar casein (MC) powder that were heat-treated at 70 °C. Thiol groups were variably blocked with N-ethylmaleimide (NEM). The gels were characterized using stress–strain measurements, rheological analyses, and confocal microscopy. The stress–strain curves exhibited a biphasic behavior, with an initial linear elastic phase followed by a linear plastic region and a nonlinear failure zone. Compared to control samples, the addition of 100 mM NEM reduced the gel strength by 50%, while G′ and G″ increased by around 100%, unexpectedly. NEM-treated gels consist of uniformly sized building blocks coated with a whey protein layer. Strong physical interactions and dense packing enhance viscoelasticity under short deformations but reduce the compressive strength during prolonged loading. In contrast, control samples without NEM demonstrate weak viscoelasticity and increased compressive strength. The former is attributed to a broader particle size distribution from lower acid stability in the untreated gels, while the particularly high compressive strength of heat-treated gels additionally results from disulfide cross-links. The results show that thiol blocking and heating enable the targeted formation of acid casein gels with high shear stability but a low compressive strength. Full article

Marine heatwaves (MHWs) have recently become more frequent, intense, and prolonged, posing significant threats to marine life and fisheries. In this study, transcriptomic analysis was employed to investigate the genes and pathways in Seriola dumerili that respond to MHW-induced stress at 28 °C (T28) and 32 °C (T32), using 24 °C (T24) as the control. Transcriptome sequencing revealed that 17 differentially expressed genes (DEGs) belonging to the heat shock protein (HSP) families—HSP30, HSP40, HSP70, and HSP90—were significantly upregulated under short-lasting MHW stress in the T24-4d vs. T32-4d comparison. Additionally, genes related to oxidative stress (e.g., protein disulfide isomerase family A member 6 [pdia6]), immune responses (e.g., interferon regulatory factor 5 [irf5]), and energy metabolism (e.g., hexokinase-1 [hk1]) were also identified. Enrichment analysis of DEGs in the T24-4d vs. T32-4d group revealed that S. dumerili exhibited adaptive responses to MHWs through the upregulation of HSPs and the activation of antioxidant, energy metabolism, and immune response pathways. However, in the T24-13d vs. T32-13d group, DEGs associated with these pathways were either not significantly expressed or were downregulated. These findings indicate that S. dumerili is unable to sustain its adaptive responses under repeated, intense MHW exposure, resulting in the disorder of its antioxidant defense system, immune suppression, and metabolic dysfunction. This study provides valuable insights into the molecular responses of S. dumerili to MHWs and supports the selection for thermal resistance in this species. Full article

Background/Objectives: In the past 50 years, human reproductive capacity has steadily declined with elusive and idiopathic origins. Amongst theorized causes, oxidative stress has been proposed to directly contribute to male infertility. The glutathione (GSH) and glutathione disulfide (GSSG) molecular couple reflect cellular redox environments and are thus reflective of oxidative stress in most cells. Shifting GSH/GSSG redox states to abnormal, more oxidizing conditions can disrupt normal cellular activities. This study explores the correlation between the GSH/GSSG redox system and factors involved in male infertility, including sperm quality, specifically sperm motility and total count. Methods: Semen samples from 98 patients underwent high-performance liquid chromatography (HPLC) for GSH/GSSG analysis. A protein assay determined the protein concentration for normalization, and GSH/GSSG redox potentials (E_h) were calculated using the Nernst equation. Results: A significant inverse correlation between GSH/GSSG E_h and sperm count was identified (p = 0.0046 and R² = 0.071). Analysis also found that cellular GSH concentrations (p < 0.001 and R² = 0.11) and total GSH (GSH + (GSSG × 2); p = 0.0039 and R² = 0.074) were significantly and positively correlated with total sperm count, whereas GSSG concentrations were not. The correlation between redox potential and motility was not significantly different (p = 0.11 and R² = 0.02). Conclusions: This study shows that total sperm count decreases with increasing redox potential, indicating that more oxidized systems, such as the GSH/GSSG system, are associated with lower sperm counts in ejaculated sperm samples. These findings support a potential link between oxidative stress and sperm parameters. As understanding of the relationship between GSH/GSSG E_h and sperm quality improves, this may inform future potential therapies and approaches aimed at supporting male reproductive health. Full article

Background/Objectives: Desiccation profoundly influences the distribution and abundance of intertidal seaweeds, necessitating robust molecular adaptations. Sargassum muticum is a brown seaweed inhabiting intertidal rocky substrates. During low tides, this species undergoes periodic aerial exposure. Such environmental conditions necessitate robust physiological mechanisms to mitigate desiccation stress. Yet, the molecular basis of this adaptation remains poorly understood. Methods: To investigate desiccation-responsive genes and elucidate the underlying mechanisms of adaptation, we exposed S. muticum to 6 h of controlled desiccation stress in sterilized ceramic trays, simulating natural tidal conditions, and performed comparative transcriptome analysis using RNA-seq on the Illumina NovaSeq 6000 platform. Results: High-quality sequencing identified 66,192 unigenes, with 1990 differentially expressed genes (1399 upregulated and 591 downregulated). These differentially expressed genes (DEGs) were categorized into regulatory genes—including mitogen-activated protein kinase (MAPK), calmodulin, elongation factor, and serine/threonine-protein kinase—and functional genes, such as heat shock protein family members (HSP20, HSP40, and HSP70), tubulin (TUBA and TUBB), and endoplasmic reticulum homeostasis-related genes (protein disulfide-isomerase A6, calreticulin, and calnexin). Gene Ontology (GO) enrichment highlighted upregulated DEGs in metabolic processes like glutathione metabolism, critical for oxidative stress mitigation, while downregulated genes were linked to transport functions, such as ammonium transport, suggesting reduced nutrient uptake during dehydration. KEGG pathway analysis revealed significant enrichment in “protein processing in endoplasmic reticulum” and “MAPK signaling pathway-plant”, implicating endoplasmic reticulum stress response and conserved signaling cascades in desiccation adaptation. Validation via qRT-PCR confirmed consistent expression trends for key genes, reinforcing the reliability of transcriptomic data. Conclusions: These findings suggest that S. muticum undergoes extensive biological adjustments to mitigate desiccation stress, highlighting candidate pathways for future investigations into recovery and tolerance mechanisms. Full article

The human CHCHD4 protein, which is a prototypical family member, carries a coiled–coil–helix–coiled–coil–helix motif that is stabilized by two disulfide bonds. Using its CPC sequence motif, CHCHD4 plays a key role in mitochondrial metabolism, cell survival, and response to stress conditions, controlling the mitochondrial import of diversified protein substrates that are specifically recognized through an interplay between covalent and non-covalent interactions. In the present review, we provide an updated and comprehensive analysis of CHCHD4 substrates controlled by its redox activities. A particular emphasis has been placed on the molecular and structural aspects of these partnerships. The literature survey has been integrated with the mining of structural databases reporting either experimental structures (Protein Data Bank) or structures predicted by AlphaFold, which provide protein three-dimensional models using machine learning-based approaches. In providing an updated view of the thirty-four CHCHD4 substrates that have been experimentally validated, our analyses highlight the notion that this protein can operate on a variety of structurally diversified substrates. Although in most cases, CHCHD4 plays a crucial role in the formation of disulfide bridges that stabilize helix–coil–helix motifs of its substrates, significant variations on this common theme are observed, especially for substrates that have been more recently identified. Full article

Atopic dermatitis (AD) is one of the forms of allergic dermatitis and the most common chronic recurring inflammatory skin disease. In case of allergic dermatitis, oxidative stress (OS) promotes inflammation, disrupts the skin’s barrier function, and facilitates the penetration of allergens into the body. As a result, studying oxidative stress and its influence on the course and spread of these diseases is important in the search for new treatment strategies. This literature review aims to discover the effect of oxidative stress on the course of atopic dermatitis and review additional options for treatment. A comprehensive literature review was performed using the medical databases “PubMed” and the specialized search engine “Google Scholar” using the PICO model. Analyzed scientific articles were published from 2019 to 2024 in English. Of the 167 initial studies, 51 articles were included based on relevance, language, and release date. The other 116 articles were rejected due to incomplete publications and publications involving animals. Key biomarkers are associated with oxidative stress, including urinary 8-hydroxydeoxyguanosine (8-OHdG), malondialdehyde (MDA), glutathione, and glutathione disulfide, and they correlate directly with the severity of atopic dermatitis. This research emphasizes that antioxidants, such as vitamins, sun protection, coenzyme Q10, a balanced diet, melatonin, flavonoids, and NB-UVB therapy may have a positive impact on the pathogenesis and progression of atopic dermatitis. Full article

Introduction: Hair damage from chemical treatments, mechanical stress, and environmental factors can lead to significant degradation in hair quality, necessitating effective solutions for restoration. The aim of this study was to develop and evaluate novel compounds for repairing hair damage through the chemical regeneration of disulfide bridges. Materials and Methods: Three novel thiol-reactive cross-linking agents (APA, STA, SAA) were synthesized and characterized. Their efficacy in repairing hair damage was evaluated through in vitro tensile strength tests on human hair fibers, comparing treated and untreated samples. Cysteine reactivity tests were also performed to assess the capability of these agents to restore disulfide bridges in hair keratin. Results: The tensile strength tests revealed significant improvements in the mechanical properties of treated hair fibers compared to untreated samples. APA demonstrated the highest efficacy in restoring tensile strength and elasticity, showing higher performance in mechanical strengthening. The cysteine reactivity tests confirmed that APA could effectively re-establish disulfide bonds, particularly at higher temperatures. STA, while less effective than APA, showed substantial efficiency in restoring disulfide bonds. When compared to the reference agent, both APA and STA exhibited higher performance in tensile strength and cysteine reactivity, with APA showing the greatest improvement in mechanical properties. Conclusions: Our study successfully revealed the potential of the synthesized thiol-reactive cross-linking agents in repairing hair damage by chemically regenerating disulfide bridges. These findings offer a promising new direction for the development of advanced hair repair treatments in the cosmetic industry. Full article

Pequi oil (PO) is a natural feed additive rich in bioactive compounds, which can modulate antioxidant and immunological systems. Thus, the aim of this study was to evaluate the proteomic profile of laying hens supplemented with PO under heat stress conditions. Ninety-six 26-week-old Lohmann White hens were housed in a completely randomized design with a 2 × 2 factorial arrangement, with two climate chambers (cyclic heat stress and thermoneutral) and two diets (control and 0.6% PO). At 38 weeks old, liver samples were collected for protein extraction and digestion, and were submitted to liquid chromatography–tandem mass spectrometry (LC-MS/MS). A total of 996 differentially expressed proteins were identified in the liver proteome of laying hens fed with 0.6% PO under heat stress. These upregulated proteins (0.95 ≤ p ≤ 1.00) are associated with lipid metabolism (apolipoprotein B; vitellogenin-1; ovotransferrin), the antioxidant system (protein disulfide-isomerase A4; superoxide dismutase 1_ soluble; catalase), the immune system (Ig-like domain-containing protein) and chaperones (HSP 90; HSP 70). PO positively modulates a network of heat shock proteins and antioxidant enzymes, and the unique proteins identified can contribute to the discovery of new biomarkers related to heat stress reduction by phytogenic additives. Full article

Background: In recent years, interest in probiotic supplementation has increased among athletes due to its potential benefits on sports performance. Thus, the aim of this trial was to investigate Lactobacillus plantarum’s effects on sports performance, intestinal damage, and oxidative stress biomarkers. Methods: Twenty-two physically active participants, nine females and thirteen males (age: 32.8 ± 5.2 years; height: 1.73 ± 0.1 m (meters); body mass: 72.2 ± 10.3 kg (kilograms) volunteered in this randomized, double-blind, placebo-controlled, parallel study. The participants performed a strenuous exercise session, and immediately after, their perceived exertion was assessed and blood samples were drawn to assess intestinal damage (IFABP: intestinal fatty acid binding protein) and oxidative stress (PC: protein carbonyls; TAC: total antioxidant capacity; total proteins; GSSG: glutathione disulfide; GSH: reduced glutathione and catalase). Twenty-four hours later, the participants ranked their recovery status and completed various sports performance tests: CMJ (countermovement jump), RAST (running-based anaerobic sprint), and YOYO IR1 (YOYO intermittent recovery test level 1). This was followed by a four-week supplementation period, in which the participants ingested one probiotic capsule per day containing 10 billion CFU (colony forming units) of Lactobacillus plantarum or a placebo capsule (dextrose). Results: The paired samples t-test revealed a significantly better result in the YOYO IR1 test in the probiotic group, while a significant reduction was observed in the TAC levels in the placebo group. Conclusions: The results suggest that Lactobacillus plantarum supplementation could increase YOYO IR1 sports performance test scores and may mitigate TAC value reduction. Full article

Male infertility is intricately linked to dysregulated cell death pathways, including ferroptosis, cuproptosis, pyroptosis, and autophagy. Ferroptosis, driven by iron-dependent lipid peroxidation through the Fenton reaction and inactivation of the GPX4/Nrf2/SLC7A11 axis, disrupts spermatogenesis under conditions of oxidative stress, environmental toxin exposure, or metabolic disorders. Similarly, cuproptosis—characterized by mitochondrial dysfunction and disulfide stress due to copper overload—exacerbates germ cell apoptosis via FDX1 activation and NADPH depletion. Pyroptosis, mediated by the NLRP3 inflammasome and gasdermin D, amplifies testicular inflammation and germ cell loss via IL-1β/IL-18 release, particularly in response to environmental insults. Autophagy maintains testicular homeostasis by clearing damaged organelles and proteins; however, its dysregulation impairs sperm maturation and compromises blood–testis barrier integrity. These pathways intersect through shared regulators; reactive oxygen species and mTOR modulate the autophagy–pyroptosis balance, while Nrf2 and FDX1 bridge ferroptosis–cuproptosis crosstalk. Therapeutic interventions targeting these mechanisms have shown promise in preclinical models. However, challenges persist, including the tissue-specific roles of gasdermin isoforms, off-target effects of pharmacological inhibitors, and transgenerational epigenetic impacts of environmental toxins. This review synthesizes current molecular insights into the cell death pathways implicated in male infertility, emphasizing their interplay and translational potential for restoring spermatogenic function. Full article

Superoxide dismutase-rich Tetraselmis chuii (T. chuii) is derived from marine microalgae and has been reported to increase gene expression of nuclear factor erythroid 2-related factor 2 (NRF2) and related antioxidant enzymes in myoblast tissue culture models. Human research has indicated that T. chuii supplementation can improve recovery from exercise-induced muscle damage, but its effects on endurance exercise performance and the molecular bases that may underlie any ergogenic effects are unclear. Healthy participants underwent 14 days of supplementation with 25 mg·day⁻¹T. chuii and placebo in a randomized, double-blind, crossover experimental design. Prior to and following each supplementation period, participants completed a high-intensity cycling test to assess time to exhaustion and peak oxygen uptake (${\dot{\mathrm{V}}\mathrm{O}}_{2\mathrm{peak}}$). A resting skeletal muscle biopsy was collected after both supplementation periods to assess gene expression changes. Compared to pre-supplementation values, ${\dot{\mathrm{V}}\mathrm{O}}_{2\mathrm{peak}}$ was increased following T. chuii (p = 0.013) but not placebo (p = 0.66). Fold-change in glutathione peroxidase 7 [(GPX7) 1.26 ± 1.37], glutathione-disulfide reductase [(GSR) 1.22 ± 1.41], glutathione S-transferase Mu 3 [(GSTM3) 1.34 ± 1.49], peroxiredoxin 6 [(PRDX6) 1.36 ± 1.57], extracellular signal-regulated kinase 3 [(ERK3) 1.92 ± 2.42], NRF2 (1.62 ± 2.16), p38 alpha [(p38a) 1.33 ± 1.58] and sirtuin 1 [(SIRT1) 1.73 ± 2.25] gene expression were higher after T. chuii compared to placebo supplementation (p < 0.05). Short-term T. chuii supplementation increased ${\dot{\mathrm{V}}\mathrm{O}}_{2\mathrm{peak}}$ and skeletal muscle gene expression of key enzymatic antioxidants (GPX7, GSR, GSTM3, and PRDX6), signalling kinases (ERK3 and p38a), post-translational regulators (SIRT1), and transcription factors (NRF2) that may protect against cellular stress insults. Full article