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Measuring Oxidative Damage and Redox Signalling
Published in James N. Cobley, Gareth W. Davison, Oxidative Eustress in Exercise Physiology, 2022
James N. Cobley, Gareth W. Davison
Targeted functional analysis has been used to assess how exercise impacts ryanodine receptor carbonylation in skeletal muscle (Place et al., 2015) and can readily be extended to several adducts (e.g., 4-hydroxynoneneal). If the function of a particular oxidative damage signature is known (e.g., tyrosine nitration for MnSOD), targeted analysis simplifies interpretational complexity. For example, if acute exercise increased MnSOD nitration, one can infer decreased enzyme activity and readily confirm it with an enzyme activity assay. The rich omics literature on oxidative damage enables one to select novel targets for analysis at the systemic (i.e., secreted proteins) and tissue level. In contrast, global assays seldom yield defined chemical information, which makes functional interpretation difficult. For example, inferring whether increased global tyrosine nitration is damaging is difficult because it fails to disclose the modified proteins. Targeted analysis, therefore, establishes a technically sound platform to expand knowledge of exercise-induced oxidative damage beyond global analysis of an oxidative damage adduct by Western blot or ELISA (see Figure 2.2).
Signalling Pathways in The Regulation of Cellular Responses to Exercise
Published in Peter M. Tiidus, Rebecca E. K. MacPherson, Paul J. LeBlanc, Andrea R. Josse, The Routledge Handbook on Biochemistry of Exercise, 2020
Anders Gudiksen, Stine Ringholm, Henriette Pilegaard
Exercise has been shown to increase global glutathionylation and carbonylation in rat SkM (36), supporting the finding that a single exercise bout elicits oxidation of proteins. In accordance, the effects of ROS signalling on gene transcription have been suggested to be executed through post-translational modifications and localization of transcription factors such as NFkB and Nrf2 (3, 36, 37, 109, 122). Calcineurin has been shown to be susceptible to oxidation, which disrupts enzyme activation, indicating that also phosphatases in SkM are redox sensitive (12). In addition, endogenously produced ROS has been reported to target numerous redox active cysteine residues in proteins via S-glutathionylation (protein-SSG), disulfide bond formation (S-S), and S-nitrosation (protein-SNO) post-translational modifications indicating ROS-dependent regulation of enzyme activity (20). Together this provides evidence that ROS signalling involves multiple post-translational modifications of proteins. However, the potential ROS-mediated regulation of redox-sensitive cysteine residues in selected proteins in response to exercise would be very interesting to pursue in future studies.
Herbal Product Development and Characteristics
Published in Anil K. Sharma, Raj K. Keservani, Surya Prakash Gautam, Herbal Product Development, 2020
Mirian Pateiro, Rubén Domínguez, Predrag Putnik, Danijela Bursać Kovačević, Francisco J. Barba, Paulo S. E. Munekata, Elena Movilla Fierro, José M. Lorenzo
The mode of action of the BACs present in the extracts and in essential oils is the same as the synthetic antioxidants, commonly used in foods, such as BHA, BHT, and TBHQ. They act as free-radical scavengers, blocking free radicals by donating a hydrogen atom (Embuscado, 2015; Tongnuanchan and Bejakul, 2014). As with clinical properties, phenolic compounds are the antioxidants and effective free-radical scavengers, able to impede initiation and cascade of lipid oxidation (Hyldgaard et al., 2012). They are primary antioxidants that act in three steps against lipid oxidation: initiation, propagation, and termination. Their capacity to donate an electron to the free radical prevents the oxidation of other compounds (Yanishlieva-Maslarova, 2001). They react with free (lipid) radicals leading to nonradical species and the inactivation of peroxyl radicals, therefore inhibiting the cascade reactions leading to termination (Jayasena and Jo, 2014). Similar mechanism of action is characteristic for protein oxidation where phenolic compounds avoid protein carbonylation by joining with the proteins (Siebert et al., 1996).
Syringic acid Attenuates Oxidative Stress in Plasma and Peripheral Blood Mononuclear Cells of Patients with Acute Myeloid Leukemia
Published in Nutrition and Cancer, 2023
Naghmeh Haddadi, Mehrzad Mirzania, Hadi Ansarihadipour
ROS can cause damage to proteins and create carbonyl groups as biomarkers of protein oxidation. Our study indicated that the rate of protein carbonylation was significantly increased in patients with AML. Similarly, Rajeshwari et al. reported an increase in the level of protein carbonylation in AML patients compared with healthy individuals which was attributed to high level of ROS (48). Sabahi et al. demonstrated that the administration of SA at concentrations of 25, 50, and 100 mg/kg to diabetic rats for 6 weeks can decrease the degree of protein carbonylation in pancreatic cells (49). Similarly, we observed a decrease in the level of protein carbonylation in PBMCs and plasma samples of AML patients which treated with SA for 1 h. Also in the present study, pretreatment with SA caused a significant reduction in protein carbonylation in plasma samples and PBMCs of AML patients, indicating the antioxidant effects of SA against iron-catalyzed oxidation.
In silico prediction of post-translational modifications in therapeutic antibodies
Published in mAbs, 2022
Metal ions can catalyze oxidative carbonylation of arginine, Lys, proline (Pro), and threonine residues. Transition metals such as iron and copper can convert oxygen (O2) to superoxide radical anions (O2–·).99 During carbonylation, free radicals attack the side chain and add an amine or ketone group. Arginine and Pro are converted to glutamic semialdehyde; Lys is converted to aminoadipic semialdehyde, and threonine is converted to 2-amino-3-ketobutyric acid (Figure 4).100 Exposure to trace metals from stainless steel surfaces and glass vials can cause carbonylation of mAbs during manufacturing and storage.101 Carbonylation of arginine and Lys residues leads to a loss in positive charge, which generates acidic variants. For example, Yang et al. reported increased acidic variants after forced oxidation with ferrous sulfate and hydrogen peroxide.102 Oxidative carbonylation of mAbs can also increase protein aggregation.103
Tucumã (Astrocaryum aculeatum) extract: phytochemical characterization, acute and subacute oral toxicity studies in Wistar rats
Published in Drug and Chemical Toxicology, 2022
Camille Gaube Guex, Gabriela Buzatti Cassanego, Rafaela Castro Dornelles, Rosana Casoti, Ana Martiele Engelmann, Sabrina Somacal, Roberto Marinho Maciel, Thiago Duarte, Warley de Souza Borges, Cínthia Melazzo de Andrade, Tatiana Emanuelli, Cristiane Cademartori Danesi, Euler Esteves Ribeiro, Liliane de Freitas Bauermann
The development of chronic diseases is associated with oxidative stress, which is characterized by an imbalance between the antioxidant system and reactive species production. Malondialdehyde (MDA) is one of the final products generated by lipid peroxidation and is an important biological marker of oxidative damage (Mansour et al. 2008). Furthermore, protein carbonylation can lead to alteration in protein functions, which may result in the etiology or progression of various diseases (Levine 2002). Enzymes like CAT and SOD are part of an enzymatic defense strategy, which is responsible for neutralizing reactive species, therefore preventing oxidative damage. In this study, CETP was shown to decrease MDA levels in the renal tissue of females and increase SOD activity in the hepatic tissue of males, suggesting that the tucumã fruit may play an important role in preventing oxidative damage. These results may be attributed to the phenolic compounds found in the extract, which are known to possess high antioxidant capacity. Therefore, our results indicate that lower doses of tucumã extract are safe and have possible biological activities that may benefit the prevention and/or treatment of disorders.