Antioxidants最新文献

Plants have evolved complex mechanisms to cope with diverse abiotic stresses, with the phenylpropanoid pathway playing a central role in stress adaptation. This pathway produces an array of secondary metabolites, particularly polyphenols, which serve multiple functions in plant growth, development, regulating cellular processes, and stress responses. Recent advances in understanding the molecular mechanisms underlying phenylpropanoid metabolism have revealed complex regulatory networks involving MYB transcription factors as master regulators and their interactions with stress signaling pathways. This review summarizes our current understanding of polyphenol-mediated stress adaptations in plants, emphasizing the regulation and function of key phenylpropanoid pathway compounds. We discussed how various abiotic stresses, including heat and chilling stress, drought, salinity, light stress, UV radiation, nanoparticles stress, chemical stress, and heavy metal toxicity, modulate phenylpropanoid metabolism and trigger the accumulation of specific polyphenolic compounds. The antioxidant properties of these metabolites, including phenolic acids, flavonoids, anthocyanins, lignin, and polyphenols, and their roles in reactive oxygen species scavenging, neutralizing free radicals, membrane stabilization, and osmotic adjustment are discussed. Understanding these mechanisms and metabolic responses is crucial for developing stress-resilient crops and improving agricultural productivity under increasingly challenging environmental conditions. This review provides comprehensive insights into integrating phenylpropanoid metabolism with plant stress adaptation mechanisms, highlighting potential targets for enhancing crop stress tolerance through metabolic adjustment.

Hydroxyl radicals (^•OH), the most potent oxidants among reactive oxygen species (ROS), are a major contributor to oxidative damage of biomacromolecules, including DNA, lipids, and proteins. The overproduction of ^•OH is implicated in the pathogenesis of numerous diseases such as cancer, neurodegenerative disorders, and some cardiovascular pathologies. Given the localized nature of ^•OH-induced damage, detecting ^•OH, specifically near DNA and within organelles, is crucial for understanding their pathological roles. The major challenge of ^•OH detection results from their short half-life, high reactivity, and low concentrations within biological systems. As a result, there is a growing need for the development of highly sensitive and selective probes that can detect ^•OH in specific cellular regions. This review focuses on the advances in fluorescence probes designed to detect ^•OH near DNA and within cellular organelles and membranes. The key designs of the probes are highlighted, with emphasis on their strengths, applications, and limitations. Recommendations for future research directions are given to further enhance probe development and characterization.

Our group has recently demonstrated that exercise intervention affects the release and function of bone marrow endothelial progenitor cell-derived extracellular vesicles (EVs) in transgenic hypertensive mice. Whether such an exercise regimen can impact circulating EVs (cEVs) remains unknown. In this study, we investigated the influence of exercise on cEV level and function. Transgenic hypertensive mice (Alb1-Ren) underwent 8-week treadmill exercise (10 m/min for 1 h, 5 days per week). Age- and sex-matched sedentary Alb1-Ren mice served as controls. cEVs were isolated from the blood of exercised and sedentary mice and are denoted as ET-cEV and nET-cEV, respectively. cEVs were labeled to determine their uptake efficiency and pathways. The functions of cEVs were assessed in an Angiotensin II (Ang II) plus hypoxia-injured cerebral microvascular endothelial cell (mBMEC) injury model. Cellular migration ability and oxidative stress were evaluated. We found that treadmill exercise stimulated cEV release, and ET-cEVs were more prone to be internalized by mBMECs. The ET-cEV internalization was mediated by macropinocytosis and endocytosis pathways. Functional studies showed that ET-cEVs can improve the compromised migration capability of mBMECs challenged by Ang II plus hypoxia. Additionally, ET-cEV treatment upregulated the expression of p-Akt/Akt in mBMECs. Compared to nET-cEVs, ET-cEVs significantly reduced ROS overproduction in Ang II plus hypoxia-injured mBMECs, associated with decreased Nox2 expression. All these findings suggest that exercise-intervened cEVs can protect cerebral microvascular endothelial cells against hypertensive and hypoxic injury.

Lipid metabolism plays a critical role in maintaining cellular integrity, especially within the nervous system, where lipids support neuronal structure, function, and synaptic plasticity. However, this essential metabolic pathway is highly susceptible to oxidative stress, which can lead to lipid peroxidation, a damaging process induced by reactive oxygen species. Lipid peroxidation generates by-products that disrupt many cellular functions, with a strong impact on proteostasis. In this review, we explore the role of lipid oxidation in protein folding and its associated pathological implications, with a particular focus on findings in neurodegeneration from Caenorhabditis elegans studies, an animal model that remains underutilized. Additionally, we highlight the effectiveness of different methodologies applied in this nematode to deepen our understanding of this intricate process. In the nervous system of any animal, including mammals and invertebrates, lipid oxidation can disturb the delicate balance of cellular homeostasis, leading to oxidative stress, the build-up of toxic by-products, and protein misfolding, key factors in neurodegenerative diseases. This disruption contributes to the pathogenesis of neurodegenerative disorders such as Alzheimer's, Parkinson's, or Huntington's disease. The findings from Caenorhabditis elegans studies offer valuable insights into these complex processes and highlight potential avenues for developing targeted therapies to mitigate neurodegenerative disease progression.

Sperm cryopreservation provides patients undergoing oncological, surgical, or infertility treatments the opportunity to conceive their own children, using assisted reproductive technologies. However, the freezing-thawing process can negatively influence both the quantity and the quality of spermatozoa, mainly due to an excessive production of reactive oxygen species and/or an impaired antioxidant defense system in sperm. Aromatic and medicinal plants synthesize essential oils with antioxidant proprieties as a part of their ecological adaptation to environmental stress, thanks to their rich bioactive phytochemical components. This study aimed to assess sperm progressive motility, viability, plasma membrane functionality, and lipid peroxidation levels of human cryopreserved normozoospermic (n = 51) and asthenozoospermic (n = 51) samples without or with the addition of Thymus satureoides (TSEO) (20 µg/mL), Artemisia vulgaris (AVEO) (48 µg/mL), and Rosmarinus officinalis (ROEO) (13 µg/mL) essential oils. Sperm parameters were significantly better preserved with ROEO in both normozoospermic (p < 0.05) and asthenozoospermic samples (p < 0.01). In contrast, TSEO had a negative impact for both groups (p < 0.05). Meanwhile, no significant effects were observed with AVEO. In summary, the study revealed that in vitro addition of essential oils as antioxidant agents during cryopreservation can be either beneficial, which helps preserve sperm parameters and fertilizing potential, or detrimental as spermicidal agents.

Mutations in highly conserved genes encoding components of the electron transport chain (ETC) provide valuable insights into the mechanisms of oxidative stress and mitochondrial ROS (mtROS) in a wide range of diseases, including cancer, neurodegenerative disorders, and aging. This review explores the structure and function of the ETC in the context of its role in mtROS generation and regulation, emphasizing its dual roles in cellular damage and signaling. Using Caenorhabditis elegans as a model organism, we discuss how ETC mutations manifest as developmental abnormalities, lifespan alterations, and changes in mtROS levels. We highlight the utility of redox sensors in C. elegans for in vivo studies of reactive oxygen species, offering both quantitative and qualitative insights. Finally, we examine the potential of C. elegans as a platform for testing ETC-targeting drug candidates, including OXPHOS inhibitors, which represent promising avenues in cancer therapeutics. This review underscores the translational relevance of ETC research in C. elegans, bridging fundamental biology and therapeutic innovation.

This study investigated the potential of natural deep eutectic solvents (NADESs) for extracting bioactive compounds from the aerial parts of two mountain tea taxa, Sideritis clandestina ssp. peloponnesiaca (Boiss. & Heldr.) Baden and Sideritis raeseri Boiss. & Heldr. ssp. raeseri. Five NADEs, composed of betaine, glycerol, glucose, urea, citric acid, and sucrose, were evaluated for their extraction efficiency compared to conventional solvents (water and 70% ethanol). The total phenolic content (TPC) and antioxidant activity (FRAP and DPPH assays) were determined. Results showed that water was not a good extraction solvent. Despite the great solvent-dependent differences, most NADEs, particularly the betaine-glycerol-glucose mixture (BGG4), exhibited comparable or even superior extraction efficiency and antioxidant activity compared to 70% ethanol. The secondary metabolites in the BGG4 and 70% ethanol extracts were determined with HPLC-MS. The BGG4 extracts of both Sideritis taxa had a rich phenolic profile, with the major ingredients being chlorogenic acid, verbascoside, and non-, mono- and di-acetylated allosyl hypolaetin glycosides. Although distinct quantitative differences in their composition compared to the respective 70% ethanol extracts, and between them were noted, overall, the content of secondary metabolites in both S. raeseri extracts was lower than that of the S. clandestina extracts. These findings suggest that NADEs, particularly BGG4, are promising green solvents for extracting bioactive compounds from Sideritis taxa, paving the way for potential applications in the development of natural and sustainable cosmetic products.

Background: Male professional soccer players frequently compete in multiple matches weekly, and each match significantly impacts their homeostasis, health, and performance. This study evaluates players response at 48 h post-match by combining biological and GPS data. Investigating biochemical and performance metrics offers insights into the physical demands of high-intensity exercise, essential for optimizing performance, recovery, and overall athlete health.

Methods: The study involved an Italian "Serie A" team, and we assessed players' effort during a single match using GPS data and compared it to "Serie A" averages. Additionally, we evaluated oxidative stress and metabolism 48 h after the match.

Results: At 48 h post-match, there were no signs of oxidative stress and changes in salivary IgA levels, but total antioxidant potential was significantly low. Moreover, increased plasma metabolites linked to energy production were also observed.

Conclusions: The results indicate that 48 h after a match in "Serie A", well-trained athletes showed no oxidative stress, to the detriment of the antioxidant potential, along with increased metabolites crucial for energy production. Combining GPS and metabolic analysis enhances player performance, informs tactical decisions, and supports team success, fostering data-driven approaches in soccer.

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder that significantly increases the risk of cardiovascular disease, which is the leading cause of morbidity and mortality among diabetic patients. A central pathophysiological mechanism linking T2DM to cardiovascular complications is oxidative stress, defined as an imbalance between reactive oxygen species (ROS) production and the body's antioxidant defenses. Hyperglycemia in T2DM promotes oxidative stress through various pathways, including the formation of advanced glycation end products, the activation of protein kinase C, mitochondrial dysfunction, and the polyol pathway. These processes enhance ROS generation, leading to endothelial dysfunction, vascular inflammation, and the exacerbation of cardiovascular damage. Additionally, oxidative stress disrupts nitric oxide signaling, impairing vasodilation and promoting vasoconstriction, which contributes to vascular complications. This review explores the molecular mechanisms by which oxidative stress contributes to the pathogenesis of cardiovascular disease in T2DM. It also examines the potential of lifestyle modifications, such as dietary changes and physical activity, in reducing oxidative stress and mitigating cardiovascular risks in this high-risk population. Understanding these mechanisms is critical for developing targeted therapeutic strategies to improve cardiovascular outcomes in diabetic patients.

The increasing prevalence of monocultures has reduced floral diversity, diminishing pollen diet variety for bees. This study examines the impact of monofloral pollen diets (hazel, rapeseed, pine, buckwheat, Phacelia, goldenrod) on the antioxidant enzyme activities in the fat body from tergite 3, tergite 5, sternite, and hemolymph of honey bees. We show that pollen from plants such as rapeseed, Phacelia, buckwheat, and goldenrod (rich in phenolic compounds and flavonoids) increases the activities of SOD, CAT, GST, and GPx in the fat body and hemolymph compared to the control group. Although it is commonly known that a monodiet is one of the stress factors for bees, the increase in the activities of these enzymes in the hemolymph and fat body of workers fed with pollen candy compared to those fed only sugar candy has a positive (although inconclusive) effect. These activities in the hemolymph and fat body of bees fed with pollen from anemophilous plants are usually lower compared to those in bees fed with candy containing 10% pollen from rapeseed, Phacelia, buckwheat, or goldenrod. Further research is needed to fully understand the complex interactions among monofloral pollen diets, antioxidant enzyme activities, and the overall physiology of honey bees.