antioxidant defenses
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PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262233
Author(s):  
Binish Arif ◽  
Zarina Arif ◽  
Jamal Ahmad ◽  
Kahkashan Perveen ◽  
Najat A. Bukhari ◽  
...  

The micro- and macro-complications in diabetes mellitus (DM) mainly arise from the damage induced by Amadori and advanced glycation end products, as well as the released free radicals. The primary goal of DM treatment is to reduce the risk of micro- and macro-complications. In this study, we looked at the efficacy of aminoguanidine (AG) to prevent the production of early glycation products in alloxan-diabetic rabbits. Type1 DM was induced in rabbits by a single intravenous injection of alloxan (90 mg/kg body weight). Another group of rabbits was pre-treated with AG (100 mg/kg body weight) prior to alloxan injection; this was followed by weekly treatment with 100 mg/kg of AG for eight weeks. Glucose, insulin, and early glycation products (HbA1C and fructosamine) were measured in control, diabetic and AG treated diabetic rabbits. The effects of hyperglycemia on superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (Gpx), reduced glutathione (rGSH), nitric oxide, lipid peroxides, and protein carbonyl were investigated. Alloxan-diabetic rabbits had lower levels of SOD, CAT, Gpx, and rGSH than control rabbits. Nitric oxide levels were considerably greater. AG administration restored the activities of SOD, CAT, Gpx enzymes up to 70–80% and ameliorated the nitric oxide production. HbA1c and fructosamine levels were considerably lower in AG-treated diabetic rabbits. The observed control of hyperglycemia and amadori adducts in alloxan-diabetic rabbits by AG may be attributed to decrease of stress and restoration of antioxidant defenses.


Antioxidants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 67
Author(s):  
Maria Ansar ◽  
Yue Qu ◽  
Teodora Ivanciuc ◽  
Roberto P. Garofalo ◽  
Antonella Casola

Respiratory syncytial virus (RSV) infection in mouse and human lung is associated with pathogenic inflammation and oxidative injury. RSV impairs antioxidant responses by increasing the degradation of transcription factor NF-E2-related factor 2 (NRF2), which controls the expression of several antioxidant enzymes (AOEs). In addition to its protective effects, type I IFNs have been increasingly recognized as important mediators of host pathogenic responses during acute respiratory viral infections. We used a mouse model of RSV infection to investigate the effect of lack of type I interferon (IFN) receptor on viral-mediated clinical disease, airway inflammation, NRF2 expression, and antioxidant defenses. In the absence of type I IFN signaling, RSV-infected mice showed significantly less body weight loss and airway obstruction, as well as a significant reduction in cytokine and chemokine secretion and airway inflammation. Lack of type I IFN receptor was associated with greatly reduced virus-induced promyelocytic leukemia lung protein expression, which we showed to be necessary for virus-induced NRF2 degradation in a cell model of infection, resulting in restoration of NRF2 levels, AOE expression, and airway antioxidant capacity. Our data support the concept that modulation of type I IFN production and/or signaling could represent an important therapeutic strategy to ameliorate severity of RSV-induced lung disease.


Antioxidants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 50
Author(s):  
Premranjan Kumar ◽  
Ob Osahon ◽  
David B. Vides ◽  
Nicola Hanania ◽  
Charles G. Minard ◽  
...  

Humanity is battling a respiratory pandemic pneumonia named COVID-19 which has resulted in millions of hospitalizations and deaths. COVID-19 exacerbations occur in waves that continually challenge healthcare systems globally. Therefore, there is an urgent need to understand all mechanisms by which COVID-19 results in health deterioration to facilitate the development of protective strategies. Oxidative stress (OxS) is a harmful condition caused by excess reactive-oxygen species (ROS) and is normally neutralized by antioxidants among which Glutathione (GSH) is the most abundant. GSH deficiency results in amplified OxS due to compromised antioxidant defenses. Because little is known about GSH or OxS in COVID-19 infection, we measured GSH, TBARS (a marker of OxS) and F2-isoprostane (marker of oxidant damage) concentrations in 60 adult patients hospitalized with COVID-19. Compared to uninfected controls, COVID-19 patients of all age groups had severe GSH deficiency, increased OxS and elevated oxidant damage which worsened with advancing age. These defects were also present in younger age groups, where they do not normally occur. Because GlyNAC (combination of glycine and N-acetylcysteine) supplementation has been shown in clinical trials to rapidly improve GSH deficiency, OxS and oxidant damage, GlyNAC supplementation has implications for combating these defects in COVID-19 infected patients and warrants urgent investigation.


2021 ◽  
Vol 29 ◽  
Author(s):  
Azzurra Chiara De Maio ◽  
Giovanna Basile ◽  
Domenico Iacopetta ◽  
Alessia Catalano ◽  
Jessica Ceramella ◽  
...  

Abstract: Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) mainly affecting the colon and the rectum. Its main characters are represented by relapsing and remitting mucosal inflammation, starting in the rectum and typically extending continuously proximally through part or the entire colon. UC pathogenesis depends on multiple factors, such as genetic predisposition, defects in the epithelial barrier, dysregulated immune responses, and environmental causes. The most frequent symptoms are abdominal pain, weight loss, mucus discharge, bloody diarrhoea, incontinence, nocturnal defecations, fever, and anemia. Existing therapies for UC include 5-aminosalicylic acid (5-ASA) and its derivatives, steroids, immunosuppressants and biological drugs. However, limited efficacy and unwanted adverse effects hardly limit these strategies of treatment. In the last decades, research studies have been driven towards complementary and alternative medicines for the treatment of UC. Various nutraceuticals have exhibited promising results in modulating intestinal inflammation meanwhile improving symptoms. These compounds possess a wide spectrum of positive health effects evidenced by in vitro studies, characterized by their involvement in antioxidant defenses, cell proliferation, and gene expression. The present review analyzes the available data about the different types of nutraceuticals and their potential effectiveness as adjuvant therapy of IBD, with particular emphasis to UC.


Cells ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 38
Author(s):  
Vinay Choubey ◽  
Akbar Zeb ◽  
Allen Kaasik

Mitochondria in the cell are the center for energy production, essential biomolecule synthesis, and cell fate determination. Moreover, the mitochondrial functional versatility enables cells to adapt to the changes in cellular environment and various stresses. In the process of discharging its cellular duties, mitochondria face multiple types of challenges, such as oxidative stress, protein-related challenges (import, folding, and degradation) and mitochondrial DNA damage. They mitigate all these challenges with robust quality control mechanisms which include antioxidant defenses, proteostasis systems (chaperones and proteases) and mitochondrial biogenesis. Failure of these quality control mechanisms leaves mitochondria as terminally damaged, which then have to be promptly cleared from the cells before they become a threat to cell survival. Such damaged mitochondria are degraded by a selective form of autophagy called mitophagy. Rigorous research in the field has identified multiple types of mitophagy processes based on targeting signals on damaged or superfluous mitochondria. In this review, we provide an in-depth overview of mammalian mitophagy and its importance in human health and diseases. We also attempted to highlight the future area of investigation in the field of mitophagy.


2021 ◽  
Vol 22 ◽  
Author(s):  
Idris Zubairu Sadiq

: Free radical contained one or more unpaired electrons in its valence shell, thus making it unstable, short-lived and highly reactive specie. Excessive generation of these free radicals ultimately leads to oxidative stress causing oxidation and damage to significant macromolecules in the living system and essentially disrupting signal transduction pathways and antioxidants equilibrium. At lower concentrations, ROS serves as “second messengers” influencing many physiological processes in the cell. However, at higher concentrations beyond cell capacity causes oxidative stress, which contributes to much human pathology such as diabetes, cancer, Parkinson’s disease, cardiovascular diseases, cataract, asthma, hypertension, atherosclerosis, arthritis and Alzheimer’s disease. Signaling pathways such as NF-κB, MAPKs, PI3K/Akt/ mTOR and Keap1-Nrf2-ARE modulates the detrimental effects of oxidative stress by increasing the expression of cellular antioxidant defenses, phase II detoxification enzymes and decreased production of ROS. Free radicals such as H2O2 are indeed needed for the advancement of cell cycle as these molecules influences DNA, proteins and enzymes in the cell cycle pathway. In the course of cell cycle progression, the cellular redox environment becomes more oxidized moving from G1 phase, becomes higher in G2/M and moderate in S phase. Signals in the form of an increase in cellular pro-oxidant levels are required and these signals are often terminated by a rise in the amount of antioxidants and MnSOD with a decrease in the level of cyclin D1 proteins. Therefore, understanding the mechanism of cell cycle redox regulation will help in therapy of many diseases.


Antioxidants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 8
Author(s):  
Stephanie M. Boas ◽  
Kathlene L. Joyce ◽  
Rita M. Cowell

Oxidative stress has been implicated in the etiology and pathobiology of various neurodegenerative diseases. At baseline, the cells of the nervous system have the capability to regulate the genes for antioxidant defenses by engaging nuclear factor erythroid 2 (NFE2/NRF)-dependent transcriptional mechanisms, and a number of strategies have been proposed to activate these pathways to promote neuroprotection. Here, we briefly review the biology of the transcription factors of the NFE2/NRF family in the brain and provide evidence for the differential cellular localization of NFE2/NRF family members in the cells of the nervous system. We then discuss these findings in the context of the oxidative stress observed in two neurodegenerative diseases, Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS), and present current strategies for activating NFE2/NRF-dependent transcription. Based on the expression of the NFE2/NRF family members in restricted populations of neurons and glia, we propose that, when designing strategies to engage these pathways for neuroprotection, the relative contributions of neuronal and non-neuronal cell types to the overall oxidative state of tissue should be considered, as well as the cell types which have the greatest intrinsic capacity for producing antioxidant enzymes.


Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2012
Author(s):  
Silvia Martini ◽  
Laura Castellini ◽  
Roberta Parladori ◽  
Vittoria Paoletti ◽  
Arianna Aceti ◽  
...  

Free radicals play a role of paramount importance in the development of neonatal brain injury. Depending on the pathophysiological mechanisms underlying free radical overproduction and upon specific neonatal characteristics, such as the GA-dependent maturation of antioxidant defenses and of cerebrovascular autoregulation, different profiles of injury have been identified. The growing evidence on the detrimental effects of free radicals on the brain tissue has led to discover not only potential biomarkers for oxidative damage, but also possible neuroprotective therapeutic approaches targeting oxidative stress. While a more extensive validation of free radical biomarkers is required before considering their use in routine neonatal practice, two important treatments endowed with antioxidant properties, such as therapeutic hypothermia and magnesium sulfate, have become part of the standard of care to reduce the risk of neonatal brain injury, and other promising therapeutic strategies are being tested in clinical trials. The implementation of currently available evidence is crucial to optimize neonatal neuroprotection and to develop individualized diagnostic and therapeutic approaches addressing oxidative brain injury, with the final aim of improving the neurological outcome of this population.


2021 ◽  
Vol 7 (12) ◽  
pp. 1039
Author(s):  
Nadia Mohamed El-Shafey ◽  
Marym A. Marzouk ◽  
Manal M. Yasser ◽  
Salwa A. Shaban ◽  
Gerrit T.S. Beemster ◽  
...  

Heavy metal contamination in soil is increasing rapidly due to increasing anthropogenic activities. Despite the importance of rose-scented geranium as a medicinal plant, little attention was paid to enhancing its productivity in heavy metal-polluted soil. In this regard, endophytes improve plant resistance to heavy metal toxicity and enhance its tissue quality. Here, the impact of the three endophytic fungi Talaromyces versatilis (E6651), Emericella nidulans (E6658), and Aspergillus niger (E6657) on geranium growth, tolerance, and tissue quality under cadmium (Cd) stress was investigated. In contrast to E. nidulans, T. versatilis and A. niger enhanced geranium growth and the stimulatory effect was more pronounced under Cd-stress. The three endophytes significantly alleviated Cd accumulation and increased mineral content in geranium leaves. In addition, endophytic fungi successfully alleviated Cd-induced membrane damage and reinforced the antioxidant defenses in geranium leaves. Inoculation with endophytes stimulated all the antioxidant enzymes under Cd-stress, and the response was more obvious in the case of T. versatilis and A. niger. To reduce the toxicity of tissue-Cd levels, T. versatilis and A. niger upregulated the detoxification mechanisms; glutathione-S-transferase, phytochelatin, and metallothionein levels. Moreover, endophytic fungi improved the medicinal value and quality of geranium by increasing total antioxidant capacity (TAC), phenolic compound biosynthesis (phenylalanine ammonia-lyase), and vitamin content as well as the quantity and quality of essential oil, particularly under Cd-stress conditions. The variation in the mechanisms modulated by the different endophytic fungi was supported by Principal Component Analysis (PCA). Overall, this study provided fundamental insights into endophytes’ impact as a feasible strategy to mitigate the phytotoxicity hazards of Cd-stress in geranium and enhance its quality, based on the growth and biochemical investigations.


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