Search Results (15,428)

Calcium-dependent protein kinases (CDPKs), which are activated by transient changes in the Ca²⁺ concentration in plants, are important for various biological processes, such as growth, development, defense against biotic and abiotic stresses, and others. Mannitol is commonly used as an osmotic regulatory substance in culture medium or nutrient solutions to create water-deficit conditions. Here, we cloned the potato (Solanum tuberosum L.) StCDPK13 gene and generated stable transgenic StCDPK13-overexpression potato plants. To investigate the potential functions of StCDPK13 in response to drought stress, overexpression-transgenic (OE1, OE2, and OE7) and wild-type (WT) potato seedlings were cultured on MS solid media without or with mannitol, representing the control or drought stress, for 20 days; the elevated mannitol concentrations (150 and 200 mM) were the drought stress conditions. The StCDPK13 gene was consistently expressed in different tissues and was induced by drought stress in both OE and WT plants. The phenotypic traits and an analysis of physiological indicators revealed that the transgenic plants exhibited more tolerance to drought stress than the WT plants. The overexpression lines showed an increased plant height, number of leaves, dry shoot weight, root length, root number, root volume, number of root tips, fresh root weight, and dry root weight under drought stress. In addition, the activities of antioxidant enzymes (CAT, SOD, and POD) and the accumulation of proline and neutral sugars were significantly increased, whereas the levels of malondialdehyde (MDA) and reactive oxygen species (ROS), including hydrogen peroxide (H₂O₂) and O₂^•−, were significantly reduced in the OE lines compared to WT plants under drought stress. Moreover, the stomatal aperture of the leaves and the water loss rate in the leaves of the OE lines were significantly reduced under drought stress compared to the WT plants. In addition, the overexpression of StCDPK13 upregulated the expression levels of stress-related genes under drought stress. Collectively, these results indicate that the StCDPK13 gene plays a positive role in drought tolerance by reducing the stomatal aperture, promoting ROS scavenging, and alleviating oxidative damage under drought stress in potatoes. Full article

Reactive oxygen species (ROS) play a pivotal role in apoptosis. We reported that Blue Light (BL) induced oxidative stress in human retinal pigment epithelial (RPE) cells in vitro and increased drusen deposition and RPE cell apoptosis in human eyes. Here, we investigated the mechanisms underlying BL-induced damage to RPE cells. Cells were exposed to BL with or without the antioxidant N-acetylcysteine. Cells were analyzed for levels of ROS, proliferation, viability, and mitochondria membrane potential (ΔΨ_M) fluctuation. We performed proteomic analyses to search for differentially expressed proteins. ROS levels increased following RPE cell exposure to BL. While ROS production did not affect RPE cell proliferation, it was accompanied by decreased ΔΨ_M and increased cell apoptosis due to the caspase cascade activation in a ROS-dependent manner. Proteomic analyses revealed that BL decreased the levels of ROS detoxifying enzymes in exposed cells. We conclude that BL-induced oxidative stress is cytotoxic to RPE cells. These findings bring new insights into the involvement of BL on RPE cell damage and its role in the progression of age-related macular degeneration. The use of antioxidants is an avenue to block or delay BL-mediated RPE cell apoptosis to counteract the disease progression. Full article

Alterations in cellular energy metabolism are a hallmark of cancer and lactate dehydrogenase (LDH) enzymes are overexpressed in many cancers regardless of sufficient oxygen and functional mitochondria. Further, L-lactate plays signaling roles in multiple cell types. We evaluated the effect of singlet oxygen and hypochlorous acid (HOCl) on pig heart LDH-B, which shares 97% homology with human LDH-B. Singlet oxygen was generated photochemically using methylene blue or the chlorophyll metabolites, pheophorbide A and chlorin e6. Singlet oxygen induced protein crosslinks observed by SDS-PAGE under reducing conditions and inhibited LDH-B activity. Ascorbate, hydrocaffeic acid, glutathione and sodium azide were employed as singlet oxygen scavengers and shown to protect LDH-B. Using fluorescein-modified maleimide, no changes in cysteine availability as a result of singlet oxygen damage were observed. This was in contrast to HOCl, which induced the formation of disulfides between LDH-B subunits, thereby decreasing LDH-B labeling with fluorescein. HOCl oxidation inhibited LDH-B activity; however, disulfide reduction did not restore it. LDH-B cysteines were resistant to millimolar H₂O₂, chloramines and Angeli’s salt. In the absence of pyruvate, LDH-B enhanced NADH oxidation in a chain reaction initiated by singlet oxygen that resulted in H₂O₂ formation. Once damaged by either singlet oxygen or HOCl, NADH oxidation by LDH-B was impaired. Full article

Peroxymonosulfate (PMS)-based advanced oxidation processes have shown potential for the removal of organic contaminants; however, the preparation of catalysts with high degradation efficiencies and rapid reaction rates remains a challenge. In this study, we have successfully synthesized CoFe bimetallic modified corn cob-derived biochar (CoFe/BC) for the activation of PMS, achieving the rapid and efficient degradation of bisphenol F (BPF). The synthesized CoFe/BC catalyst demonstrated excellent catalytic performance, achieving over 99% removal within 3 min and exhibiting a removal rate of 90.0% after five cycles. This could be attributed to the cyclic transformation of Co and Fe, which sustained rapid PMS activation for BPF degradation, and Co⁰/Fe⁰ played a significant role in the cyclic transformation. Furthermore, the electron paramagnetic resonance tests confirmed that •SO₄⁻ and •OH were the primary reactive oxygen species, while •O₂⁻ played a minor role in BPF degradation. This study highlights the high degradation efficiency, rapid reaction rate, excellent magnetic separation properties, and exceptional reusability of CoFe/BC catalysts for BPF removal, providing valuable insights for practical wastewater treatment. Full article

As a critical disease usually infected by Staphylococcus aureus, with a worldwide effect on dairy animals, subclinical mastitis is characterized by persistence and treatment resistance. During mastitis, the blood–milk barrier (BMB)’s integrity is impaired, resulting in pathogen invasion and milk quality decline. In this study, it was found that ginsenoside Rg1 (Rg1), a natural anti-inflammatory and antioxidant compound derived from ginseng, inhibited the onset of tight junction (TJ) dysfunction and ameliorated lipoteichoic acid (LTA)-induced BMB disruption inside and outside the organisms. According to subsequent mechanistic studies, Rg1 inhibited excessive autophagy and inactivated the NLRP3 inflammasome by blockading ROS generation, thereby alleviating TJ dysfunction. Peroxisome proliferator-activated receptor gamma (PPARγ) was identified as a potential target of Rg1 by means of molecular docking plus network pharmacology analysis. Furthermore, it was demonstrated that Rg1 inhibited the oxidative stress levels by activating PPARγ, and regulating the upstream autophagy-related AMPK/mTOR signaling pathway, thus decreasing excessive in vivo and in vitro autophagy. The ROS/autophagy/NLRP3 inflammasome axis was identified as a promising target for treating subclinical bovine mastitis in this study. In conclusion, Rg1 is proven to alleviate BMB disruption by activating PPARγ to inhibit oxidative stress and subsequent excessive autophagy in the case of subclinical bovine mastitis. Full article

The efficacy of photodynamic therapy (PDT) based on traditional photosensitizers is generally limited by the cellular redox homeostasis system due to the reactive oxygen species (ROS) scavenging effect of glutathione (GSH). In this study, buthionine sulfoximine (BSO), a GSH inhibitor, was conjugated with the amine group of chitosan oligosaccharide (COS) using a thioketal linker (COSthBSO) to liberate BSO and chlorine e6 (Ce6) under oxidative stress, and then, Ce6-COSthBSO NP (Ce6-COSthBSO NP), fabricated by a dialysis procedure, showed an accelerated release rate of BSO and Ce6 by the addition of hydrogen peroxide, indicating that nanophotosensitizers have ROS sensitivity. In the in vitro cell culture study using HCT116 colon carcinoma cells, a combination of BSO and Ce6 efficiently suppressed the intracellular GSH and increased ROS production compared to the sole treatment of Ce6. In particular, Ce6-COSthBSO NP showed higher efficacy in the suppression of GSH levels and ROS production compared to the free Ce6 and Ce6/BSO combination. These results were due to the fact that Ce6-COSthBSO NP was efficiently delivered to the intracellular region, suppressed intracellular GSH levels, and elevated ROS levels. The in vivo animal tumor xenograft study demonstrated Ce6-COSthBSO NP being efficiently delivered to the tumor tissue, i.e., the fluorescence intensity in the tumor tissue was higher than those of other organs. The combination of Ce6 and BSO efficiently suppressed tumor growth compared to the sole treatment of Ce6, indicating that BSO might efficiently suppress GSH levels and increase ROS levels in the tumor microenvironment. Specifically, Ce6-COSthBSO NP showed the strongest performance in inhibition of tumor growth than those of Ce6 or the CE6/BSO combination, indicating that they were efficiently delivered to tumor tissue, increased ROS levels, and then efficiently inhibited tumor growth. We suggest that COSthBSO nanophotosensitizers are promising candidates for PDT treatment of cancer cells. Full article

The immune response in plants is regulated by several phytohormones and involves the overexpression of defense genes, including the pathogenesis-related (PR-) genes. The data reported in this paper indicate that nematodes can suppress the immune response by inhibiting the expression of defense genes. Transcripts from nine defense genes were detected by qRT-PCR in the roots of tomato plants at three and seven days post-inoculation (dpi) with living juveniles (J2s) of Meloidogyne incognita (root-knot nematodes, RKNs). All the salicylic acid (SA)-responsive genes tested (PR-1, PR-2, PR-4b, PR-5) were down-regulated in response to nematode infection. On the contrary, the expression of jasmonic acid (JA)-responsive genes, including ACO (encoding the enzyme 1-aminocyclopropane-1-carboxylic acid oxidase, which catalyzes the last step of ethylene (ET) biosynthesis) and JERF3 (Jasmonate Ethylene Response Factor 3), was unaffected by the infection. Conversely, the effect of nematode attack on the activities of the defense enzymes endoglucanase and endochitinase, encoded by PR-2 and PR-3, respectively, changed depending on the tested dpi. At 5 dpi, both enzymes were inhibited in inoculated plants compared to healthy controls. The genes encoding glutathione peroxidase (GPX) and catalase (CAT), both part of the antioxidant plant system, were highly overexpressed. Additionally, the activity of the antioxidant enzymes superoxide dismutase (SOD), CAT, and ascorbate peroxidase (APX) was enhanced in infected roots. Isoelectrofocusing of root extracts revealed novel SOD isoforms in samples from inoculated plants. Furthermore, plants were pre-treated with an array of key compounds, including hormone generators, inhibitors of SA or JA-mediated defense pathways, reactive oxygen species (ROS) scavengers and generators, inhibitors of ROS generation, and compounds that interfere with calcium-mediated metabolism. After treatments, plants were inoculated with RKNs, and nematodes were allowed to complete their life cycle. Factors of plant growth and infection level in treated plants were compared with those from untreated inoculated plants. Generally, compounds that decreased SA and/or ROS levels increased infection severity, while those that reduced JA/ET levels did not affect infection rates. ROS generators induced resistance against the pests. Compounds that silence calcium signaling by preventing its intake augmented infection symptoms. The data shown in this paper indicate that SA-mediated plant immune responses are consistently suppressed during the early stages of nematode infection, and this restriction is associated with the activation of the antioxidant ROS-scavenging system. Full article

Reactive oxygen species (ROS) are double-edged swords in biological systems—they are essential for normal cellular functions but can cause damage when accumulated due to oxidative stress. Manganese superoxide dismutase (MnSOD), located in the mitochondrial matrix, is a key enzyme that neutralizes superoxide radicals (O₂^•−), maintaining cellular redox balance and integrity. This review examines the development and therapeutic potential of MnSOD mimetics—synthetic compounds designed to replicate MnSOD’s antioxidant activity. We focus on five main types: Mn porphyrins, Mn salens, MitoQ10, nitroxides, and mangafodipir. These mimetics have shown promise in treating a range of oxidative stress-related conditions, including cardiovascular diseases, neurodegenerative disorders, cancer, and metabolic syndromes. By emulating natural antioxidant defenses, MnSOD mimetics offer innovative strategies to combat diseases linked to mitochondrial dysfunction and ROS accumulation. Future research should aim to optimize these compounds for better stability, bioavailability, and safety, paving the way for their translation into effective clinical therapies. Full article

(1) Background: Laryngeal surgery due to carcinoma leads to significant tissue disruption, cellular injury, and inflammation. This leads to increased levels of reactive oxygen species (ROS), causing oxidative damage that can influence quality of life (QOL) and recovery and complicate the postoperative course. The aim of this study was to compare how postoperative quality of life and surgical complication occurrence interacted with the biomarker levels of oxidative stress (malondialdehyde, MDA; superoxide dismutase, SOD; glutathione peroxidase 1, GPX1; and catalase, CAT) and inflammation (interleukin 1, IL-1; interleukin 6, IL-6; C-reactive protein, CRP) in patients treated with conservative and radical laryngeal surgery. (2) Methods: The study included 56 patients who underwent surgical treatment for laryngeal cancer. Blood samples were collected to analyze oxidative stress and inflammation parameters before surgery and on the first and seventh days postoperatively. Serum concentrations of MDA, SOD, GPX, CAT, IL-1, IL-6, and CRP were measured using coated enzyme-linked immunosorbent assay (ELISA) kits. EORTC QLQ-H&H43 questionnaire was used to measure the QOL of patients. (3) Results and Conclusions: T stage, pain intensity, and the extent of the surgical procedure were established as significant predictive factors for QOL in multivariate analysis. There was a significant positive correlation between surgical complication occurrence and preoperative values of GPX and MDA, but significant predictors of surgical complication occurrence on the 7th postoperative day were SOD and MDA values (p < 0.05). Full article

Cisplatin (CIS) is a widely used chemotherapeutic agent, but its side effects, such as oxidative stress, inflammation, and apoptosis, often lead to male reproductive damage. Oxidative stress, primarily caused by the excessive generation of reactive oxygen species (ROS), plays a critical role in disrupting testicular homeostasis, resulting in spermatogenic impairment and tissue injury. L-cysteine (CYS), a semi-essential amino acid with potent antioxidant and anti-inflammatory properties, may offer protection against CIS-induced oxidative damage. This study aimed to assess the protective potential of CYS against CIS-induced male reproductive toxicity using in vivo and in vitro models. In vitro, treatment of TM3 (Leydig) and TM4 (Sertoli) cells with CIS led to increased ROS levels, reduced cell viability, and elevated apoptosis and inflammation, all of which were significantly ameliorated by subsequent CYS exposure. In vivo, CIS-treated male rats displayed heightened oxidative stress, impaired spermatogenesis, and histopathological damage in reproductive organs. However, CYS administration for 21 days significantly reduced oxidative stress, improved sperm viability, and protected testicular tissues from damage. These findings suggest that CYS has a protective effect against CIS-induced oxidative stress and male reproductive damage, making it a promising therapeutic agent for mitigating CIS-induced reproductive toxicity. Full article

The physiological role and the molecular architecture of the circadian clock in fully developed organisms are well established. Yet, we have a limited understanding of the function of the clock during ontogenesis. We have used a null mutant (per⁰) of the clock gene period (per) in Drosophila melanogaster to ask whether PER may play a role during normal brain development. In third-instar larvae, we have observed that the absence of functional per results in increased genotoxic stress compared to wild-type controls. We have detected increased double-strand DNA breaks in the central nervous system and chromosome aberrations in dividing neuronal precursor cells. We have demonstrated that reactive oxygen species (ROS) are causal to the genotoxic effect and that expression of PER in glia is necessary and sufficient to suppress such a phenotype. Finally, we have shown that the absence of PER may result in less condensed chromatin, which contributes to DNA damage. Full article

The interdisciplinary progress in nanotechnology has yielded environmentally friendly and cost-effective strategies to enhance bioherbicidal efficacy. This study presents the biosynthesis of silver nanoparticles (M-AgNPs) using the fungus Exserohilum rostratum, specifically targeting the Leptochloa chinensis weed in paddy fields. The M-AgNPs were characterized with an aqueous solution size of 107.9 nm and a zeta potential of −24.0 ± 0.20 mV, and their properties were analyzed by UV-Vis spectrophotometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). The application of M-AgNP suspension at different concentrations of 70 µg∙mL⁻¹, 80 µg∙mL⁻¹, and 100 µg∙mL⁻¹ to L. chinensis at the 3–4 leaf stage resulted in significant herbicidal effects. These nanoparticles induced oxidative stress and significantly reduced the activities of peroxidase, catalase, and superoxide dismutase in the weed seedlings. Meanwhile, M-AgNP treatments significantly increased the activity of cell wall-degrading enzymes, including polygalacturonase and cellulase, in L. chinensis leaves and caused organelle damage in plant leaf cells. Safety assessments showed no significant impact on rice growth after treatment with M-AgNP₃ (100 µg∙mL⁻¹) suspension. Our results suggest that M-AgNPs represent a sustainable and eco-friendly approach to weed control that is compatible with rice cultivation, thus supporting the adoption of green agricultural practices. Full article

Naphthoquinones eleutherin and isoeleutherin have demonstrated promising antibacterial activity, probably due to their quinone structure, which can generate reactive oxygen species. The study examines the activities of pathogens, such as Staphylococcus aureus and Escherichia coli, associated with antimicrobial resistance and explores their potential mechanisms of action. The MIC, IC₅₀, and MBC were determined. PharmMapper 2017 server and GOLD 2020.1 software were utilized for molecular docking to identify protein targets and interaction mechanisms. The docking predictions were verified by redocking, focusing on structures with RMSD below 2 Å. The molecular docking revealed a significant affinity of eleutherin for the peptide, transcriptional regulator QacR, and regulatory protein BlaR1 with better interactions with BlaR1 than the crystallographic ligand (benzylpenicillin). Isoeleutherin demonstrated specific interactions with methionine aminopeptidase, indicating specificity and affinity. In summary, the difference in naphthoquinones activities may be related to structural differences. Eleutherin exhibits potential as a therapeutic adjuvant to reverse bacterial resistance in S. aureus, suggesting this molecule interferes with the antibiotic resistance mechanism. The absence of homologous proteins or variations in the structure of the target proteins could be the cause of the inactivity against E. coli. Full article

Polyphenols are powerful natural antioxidants with numerous biological activities. They change cell membrane permeability, interact with receptors, intracellular enzymes, and cell membrane transporters, and quench reactive oxygen species (ROS). Yarrowia lipolytica yeast, being similar to mammalian cells, can be used as a model to study their survival ability upon long-lasting cultivation, assaying the effect of dihydroquercetin polyphenol (DHQ). The complex assessment of the physiological features of the population assaying cell respiration, survival, ROS detection, and flow cytometry was used. Y. lipolytica showed signs of chronological aging by eight weeks of growth, namely a decrease in the cell number, and size, increased ROS generation, a decrease in colony-forming unit (CFU) and metabolic activity, and decreased respiratory rate and membrane potential. An amount of 150 µM DHQ decreased ROS generation at the 6-week growth stage upon adding an oxidant of 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH). Moreover, it decreased CFU at 1–4 weeks of cultivation, inhibited cell metabolic activity of the 24-h-old culture and stimulated that on 14–56 days of growth, induced the cell respiration rate in the 24-h-old culture, and blocked alternative mitochondrial oxidase at growth late stages. DHQ serves as a mild pro-oxidant on the first day of age-stimulating anti-stress protection. In the deep stationary stage, it can act as a powerful antioxidant, stabilizing cell redox status and reducing free radical oxidation in mitochondria. It provides a stable state of population. The hormetic effects of DHQ using lower eukaryotes of Y. lipolytica have been previously discussed, which can be used as a model organism for screening geroprotective compounds of natural origin. Full article

Nanotechnology is an emerging field that involves the development of nanoscale particles, their fabrication methods, and potential applications. From nanosized inorganic particles to biopolymers, the variety of nanoparticles is unstoppably growing, offering huge opportunities for drug delivery. Various nanoformulations, such as nanoparticles, nanocomposites, and nanoemulsions, have been developed to enhance drug stability, solubility, and tissue penetration. Moreover, nanocarriers can be specifically engineered to target diseased cells or release the drug in a controllable manner, minimizing damage to surrounding healthy tissues and reducing side effects. This review focuses on the combinations between porphyrin derivatives and nanocarriers applied in photodynamic therapy (PDT). PDT has emerged as a significant advance in medicine, offering a low-invasive method for managing infections, the treatment of tumors, and various dermatoses. The therapy relies on the activation of a photosensitizer by light, which results in the generation of reactive oxygen species. Despite their favorable properties, porphyrins reveal non-specific distribution within the body. Nanotechnology has the capability to enhance the PS delivery and its activation. This review explores the potential improvements that are provided by the use of nanotechnology in the PDT field. Full article