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International Journal of Molecular... Dec 2018Cytokinins modulate a number of important developmental processes, including the last phase of leaf development, known as senescence, which is associated with... (Review)
Review
Cytokinins modulate a number of important developmental processes, including the last phase of leaf development, known as senescence, which is associated with chlorophyll breakdown, photosynthetic apparatus disintegration and oxidative damage. There is ample evidence that cytokinins can slow down all these senescence-accompanying changes. Here, we review relationships between the various mechanisms of action of these regulatory molecules. We highlight their connection to photosynthesis, the pivotal process that generates assimilates, however may also lead to oxidative damage. Thus, we also focus on cytokinin induction of protective responses against oxidative damage. Activation of antioxidative enzymes in senescing tissues is described as well as changes in the levels of naturally occurring antioxidative compounds, such as phenolic acids and flavonoids, in plant explants. The main goal of this review is to show how the biological activities of cytokinins may be related to their chemical structure. New links between molecular aspects of natural cytokinins and their synthetic derivatives with antisenescent properties are described. Structural motifs in cytokinin molecules that may explain why these molecules play such a significant regulatory role are outlined.
Topics: Antioxidants; Cytokinins; Flavonoids; Molecular Structure; Photosynthesis; Plant Development; Plant Leaves; Plants; Structure-Activity Relationship
PubMed: 30558142
DOI: 10.3390/ijms19124045 -
Oxidative Medicine and Cellular... 2018The placenta plays a vital role in fetal development during pregnancy. Dysfunction of the placenta can be caused by oxidative stress and can lead to abnormal fetal... (Review)
Review
The placenta plays a vital role in fetal development during pregnancy. Dysfunction of the placenta can be caused by oxidative stress and can lead to abnormal fetal development. Preventing oxidative stress of the placenta is thus an important measure to ensure positive birth outcomes. Research shows that tryptophan and its metabolites can efficiently clean free radicals (including the reactive oxygen species and activated chlorine). Consequently, tryptophan and its metabolites are suggested to act as potent antioxidants in the placenta. However, the mechanism of these antioxidant properties in the placenta is still unknown. In this review, we summarize research on the antioxidant properties of tryptophan, tryptophan metabolites, and metabolic enzymes. Two predicted mechanisms of tryptophan's antioxidant properties are discussed. (1) Tryptophan could activate the phosphorylation of p62 after the activation of mTORC1; phosphorylated p62 then uncouples the interaction between Nrf2 and Keap1, and activated Nrf2 enters the nucleus to induce expressions of antioxidant proteins, thus improving cellular antioxidation. (2) 3-Hydroxyanthranilic acid, a tryptophan kynurenine pathway metabolite, changes conformation of Keap1, inducing the dissociation of Nrf2 and Keap1, activating Nrf2 to enter the nucleus and induce expressions of antioxidant proteins (such as HO-1), thereby enhancing cellular antioxidant capacity. These mechanisms may enrich the theory of how to apply tryptophan as an antioxidant during pregnancy, providing technical support for its use in regulating the pregnancy's redox status and enriching our understanding of amino acids' nutritional value.
Topics: Antioxidants; Female; Humans; Placenta; Pregnancy; Tryptophan
PubMed: 30140360
DOI: 10.1155/2018/1054797 -
Medical Gas Research 2023Reactive oxygen species and other free radicals cause oxidative stress which is the underlying pathogenesis of cellular injury in various neurological diseases.... (Review)
Review
Reactive oxygen species and other free radicals cause oxidative stress which is the underlying pathogenesis of cellular injury in various neurological diseases. Molecular hydrogen therapy with its unique biological property of selectively scavenging pathological free radicals has demonstrated therapeutic potential in innumerable animal studies and some clinical trials. These studies have implicated several cellular pathways affected by hydrogen therapy in explaining its anti-inflammatory and antioxidative effects. This article reviews relevant animal and clinical studies that demonstrate neuroprotective effects of hydrogen therapy in stroke, neurodegenerative diseases, neurotrauma, and global brain injury.
Topics: Animals; Oxidative Stress; Antioxidants; Reactive Oxygen Species; Free Radicals; Hydrogen
PubMed: 36571372
DOI: 10.4103/2045-9912.359677 -
International Journal of Molecular... May 2023Cyanidin-3-O-glucoside (C3G), the most widely distributed anthocyanin (ACN) in edible fruits, has been proposed for several bioactivities, including anti-inflammatory,... (Review)
Review
Cyanidin-3-O-glucoside (C3G), the most widely distributed anthocyanin (ACN) in edible fruits, has been proposed for several bioactivities, including anti-inflammatory, neuro-protective, antimicrobial, anti-viral, anti-thrombotic and epigenetic actions. However, habitual intake of ACNs and C3G may vary widely among populations, regions, and seasons, among individuals with different education and financial status. The main point of C3G absorption occurs in the small and large bowel. Therefore, it has been supposed that the treating properties of C3G might affect inflammatory bowel diseases (IBD), such as ulcerative colitis (UC) and Crohn's disease (CD). IBDs develop through complex inflammatory pathways and sometimes may be resistant to conventional treatment strategies. C3G presents antioxidative, anti-inflammatory, cytoprotective, and antimicrobial effects useful for IBD management. In particular, different studies have demonstrated that C3G inhibits NF-κB pathway activation. In addition, C3G activates the Nrf2 pathway. On the other hand, it modulates the expression of antioxidant enzymes and cytoprotective proteins, such as NAD(P)H, superoxide dismutase, heme-oxygenase (HO-1), thioredoxin, quinone reductase-oxide 1 (NQO1), catalase, glutathione S-transferase and glutathione peroxidase. Interferon I and II pathways are downregulated by C3G inhibiting interferon-mediating inflammatory cascades. Moreover, C3G reduces reactive species and pro-inflammatory cytokines, such as C reactive protein, interferon-γ, tumor necrosis factor-α, interleukin (IL)-5, IL-9, IL-10, IL-12p70, and IL-17A in UC and CD patients. Finally, C3G modulates gut microbiota by inducing an increase in beneficial gut bacteria and increasing microbial abundances, thus mitigating dysbiosis. Thus, C3G presents activities that may have potential therapeutic and protective actions against IBD. Still, in the future, clinical trials should be designed to investigate the bioavailability of C3G in IBD patients and the proper therapeutic doses through different sources, aiming to the standardization of the exact clinical outcome and efficacy of C3G.
Topics: Humans; Anthocyanins; Antioxidants; Inflammatory Bowel Diseases; Interferons; Anti-Inflammatory Agents
PubMed: 37298350
DOI: 10.3390/ijms24119399 -
Molecules (Basel, Switzerland) Jan 2018Tibetan tea (Kangzhuan) is an essential beverage of the Tibetan people. In this study, a lyophilized aqueous extract of Tibetan tea () was prepared and analyzed by HPLC....
Tibetan tea (Kangzhuan) is an essential beverage of the Tibetan people. In this study, a lyophilized aqueous extract of Tibetan tea () was prepared and analyzed by HPLC. The results suggested that there were at least five phenolic components, including gallic acid, and four catechins (i.e., (+)-catechin, (-)-catechin gallate (), (-)-epicatechin gallate (), and (-)-epigallocatechin gallate). Gallic acid, the four catechins, and were then comparatively investigated by four antioxidant assays: ferric reducing antioxidant power, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide radical (PTIO•) scavenging, 1,1-diphenyl-2-picryl-hydrazl radical scavenging, and 2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) radical scavenging assays. In these assays, LATT, along with the five phenolic components, increased their antioxidant effects in a concentration-dependent manner; however, the half maximal scavenging concentrations of were always lower than those of . Gallic acid and the four catechins were also suggested to chelate Fe based on UV-visible spectral analysis. Ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-Q-TOF-MS/MS) analysis suggested that, when mixed with PTIO•, the five phenolic components could yield two types of radical adduct formation (RAF) products (i.e., tea phenolic dimers and tea phenolic-PTIO• adducts). In a flow cytometry assay, (+)-catechin and was observed to have a cytoprotective effect towards oxidative-stressed bone marrow-derived mesenchymal stem cells. Based on this evidence, we concluded that LATT possesses antioxidative or cytoprotective properties. These effects may mainly be attributed to the presence of phenolic components, including gallic acid and the four catechins. These phenolic components may undergo electron transfer, H⁺-transfer, and Fe-chelating pathways to exhibit antioxidative or cytoprotective effects. In these effects, two diastereoisomeric CG and ECG showed differences to which a steric effect from the 2-carbon may contribute. Phenolic component decay may cause RAF in the antioxidant process.
Topics: Animals; Antioxidants; Cell Survival; Chromatography, High Pressure Liquid; Cytoprotection; Flow Cytometry; Models, Molecular; Molecular Conformation; Molecular Structure; Phenols; Plant Extracts; Rats; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Tea; Tibet
PubMed: 29364183
DOI: 10.3390/molecules23020179 -
BioMed Research International 2019Exposure to a variety of environmental factors such as salinity, drought, metal toxicity, extreme temperature, air pollutants, ultraviolet-B (UV-B) radiation,... (Review)
Review
Exposure to a variety of environmental factors such as salinity, drought, metal toxicity, extreme temperature, air pollutants, ultraviolet-B (UV-B) radiation, pesticides, and pathogen infection leads to subject oxidative stress in plants, which in turn affects multiple biological processes via reactive oxygen species (ROS) generation. ROS include hydroxyl radicals, singlet oxygen, and hydrogen peroxide in the plant cells and activates signaling pathways leading to some changes of physiological, biochemical, and molecular mechanisms in cellular metabolism. Excessive ROS, however, cause oxidative stress, a state of imbalance between the production of ROS and the neutralization of free radicals by antioxidants, resulting in damage of cellular components including lipids, nucleic acids, metabolites, and proteins, which finally leads to the death of cells in plants. Thus, maintaining a physiological level of ROS is crucial for aerobic organisms, which relies on the combined operation of enzymatic and nonenzymatic antioxidants. In order to improve plants' tolerance towards the harsh environment, it is vital to reinforce the comprehension of oxidative stress and antioxidant systems. In this review, recent findings on the metabolism of ROS as well as the antioxidative defense machinery are briefly updated. The latest findings on differential regulation of antioxidants at multiple levels under adverse environment are also discussed here.
Topics: Antioxidants; Environment; Oxidative Stress; Plant Physiological Phenomena; Reactive Oxygen Species
PubMed: 31205950
DOI: 10.1155/2019/9732325 -
Molecules (Basel, Switzerland) Feb 2018Oxidative damage to DNA has important implications for human health and has been identified as a key factor in the onset and development of numerous diseases. Thus, it... (Review)
Review
Oxidative damage to DNA has important implications for human health and has been identified as a key factor in the onset and development of numerous diseases. Thus, it is evident that preventing DNA from oxidative damage is crucial for humans and for any living organism. Melatonin is an astonishingly versatile molecule in this context. It can offer both direct and indirect protection against a wide variety of damaging agents and through multiple pathways, which may (or may not) take place simultaneously. They include direct antioxidative protection, which is mediated by melatonin's free radical scavenging activity, and also indirect ways of action. The latter include, at least: (i) inhibition of metal-induced DNA damage; (ii) protection against non-radical triggers of oxidative DNA damage; (iii) continuous protection after being metabolized; (iv) activation of antioxidative enzymes; (v) inhibition of pro-oxidative enzymes; and (vi) boosting of the DNA repair machinery. The rather unique capability of melatonin to exhibit multiple neutralizing actions against diverse threatening factors, together with its low toxicity and its ability to cross biological barriers, are all significant to its efficiency for preventing oxidative damage to DNA.
Topics: Animals; Antioxidants; DNA Damage; DNA Repair; Free Radical Scavengers; Humans; Melatonin; Metals; Oxidation-Reduction; Oxidative Stress; Reactive Oxygen Species
PubMed: 29495460
DOI: 10.3390/molecules23030530 -
Zhongguo Yao Li Xue Bao = Acta... Nov 1998Melatonin, the chief secretory product of the pineal gland, was recently found to be a free radical scavenger and antioxidant. While most studies to date have used... (Review)
Review
Melatonin, the chief secretory product of the pineal gland, was recently found to be a free radical scavenger and antioxidant. While most studies to date have used pharmacological quantities of melatonin to limit oxidative damage, physiologic concentrations of the indole which are present in aerobic organisms have also been shown to resist molecular damage inflicted by free radicals. Melatonin has several functions in terms of its antioxidative ability. It readily scavenges the most highly toxic free radical, the hydroxyl radical, and it directly detoxifies the peroxynitrite anion, nitric oxide, singlet oxygen, and the peroxyl radical. Precisely how efficient melatonin is in neutralizing each of these toxic agents remains to be determined. Melatonin also may stimulate several antioxidative enzymes including superoxide dismutase, glutathione peroxidase, and glutathione reductase as well as inhibiting the pro-oxidative enzyme, nitric-oxide synthase. Finally, melatonin chelates transition metal ions and prevents the deterioration of cellular membranes. This combination of actions may all contribute to melatonin's ability to reduce oxidative damage. Melatonin is highly effective in reducing nuclear DNA damage and membrane lipid destruction due to toxic free radicals in vivo. These findings have implications for disease processes, eg, neurodegenerative and cardiovascular diseases, which involve free radicals and for aging itself, which also is believed to be related to accumulated oxidative damage.
Topics: Alzheimer Disease; Animals; Antioxidants; Free Radical Scavengers; Humans; Melatonin
PubMed: 10437151
DOI: No ID Found -
BMC Microbiology Apr 2023Probiotics can reduce free radical scavenging rate and oxidative damage, and improve activity of crucial antioxidative enzymes in host cells. This study aimed to isolate...
BACKGROUND
Probiotics can reduce free radical scavenging rate and oxidative damage, and improve activity of crucial antioxidative enzymes in host cells. This study aimed to isolate Bifidobacterium spp. from faeces of babies, and investigate the antioxidant effects of the Bif. longum T37a in mice weight loss and aging model induced by D-galactose.
RESULTS
T37a have good antioxidant properties in the DPPH assay and anti-lipid peroxidation test. Compared with the model group, T37a low group significantly increased the thymus index and the levels of T-AOC and GSH-Px of mice. T37a high group significantly decreased the spleen and liver index of mice and the levels of MDA in liver, significantly increased in liver HDL-C levels, and decreased LDL-C in liver.
CONCLUSIONS
T37a may be an anti-aging and weight-loss probiotics for its antioxidant capacity, and it is necessary to study further the molecular mechanism of T37a as antioxidant.
Topics: Humans; Antioxidants; Galactose; Bifidobacterium longum; Bifidobacterium; Oxidative Stress; Weight Loss
PubMed: 37061697
DOI: 10.1186/s12866-023-02846-5 -
Physiological Research 2010Oxidative stress is a phenomenon associated with pathogenetic mechanisms of several diseases including atherosclerosis, neurodegenerative diseases, such as Alzheimer's... (Review)
Review
Oxidative stress is a phenomenon associated with pathogenetic mechanisms of several diseases including atherosclerosis, neurodegenerative diseases, such as Alzheimer's and Parkinson's disease, cancer, diabetes mellitus, inflammatory diseases, as well as psychological diseases or aging processes. Oxidative stress is defined as an imbalance between production of free radicals and reactive metabolites, so-called oxidants, and their elimination by protective mechanisms, referred to as antioxidative systems. This imbalance leads to damage of important biomolecules and organs with potential impact on the whole organism. Oxidative and antioxidative processes are associated with electron transfer influencing the redox state of cells and the organism. The changed redox state stimulates or inhibits activities of various signal proteins, resulting in a changed ability of signal pathways to influence the fate of cells. At present, the opinion that oxidative stress is not always harmful, has been accepted. Depending on the type of oxidants, intensity and time of redox imbalance as well as on the type of cells, oxidative stress can play a role in the regulation of other important processes through modulation of signal pathways, influencing synthesis of antioxidant enzymes, repair processes, inflammation, apoptosis and cell proliferation, and thus processes of malignity. Imprudent administration of antioxidants may therefore have a negative impact on the organism.
Topics: Animals; Antioxidants; Homeostasis; Humans; Oxidation-Reduction; Oxidative Stress; Reactive Oxygen Species; Signal Transduction
PubMed: 19929132
DOI: 10.33549/physiolres.931844