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Recent Advancements in Microbial Degradation of Xenobiotics by Using Proteomics Approaches
Published in Vineet Kumar, Vinod Kumar Garg, Sunil Kumar, Jayanta Kumar Biswas, Omics for Environmental Engineering and Microbiology Systems, 2023
Neha Sharma, Smriti Shukla, Kartikeya Shukla, Ajit Varma, Vineet Kumar, Menaka Devi Salam, Arti Mishra
Xenobiotics cause oxidative stress by affecting various protective proteins and their expressions and are also responsible for the production of reactive nitrogen and reactive oxygen species. Overproduction of these species results in DNA, lipid, and protein damage. Reactive oxygen and nitrogen (ROS and RON) species cause various diseases such as cancer, coronary heart disease (CHD), and osteoporosis. Cellular reactions to xenobiotic-induced stress can signal proliferation, homeostasis, apoptosis, or necrosis. The cell tackles free radical generation including antioxidants and antioxidant enzymes by various means. The defence mechanisms differ from species to species (Haider et al. 2020). Oxidative stress can be counterbalanced by various antioxidants. Most xenobiotics cross cell membranes via simple diffusion. Small water-soluble molecules (up to a molecular weight of about 600) move by aqueous pores, while water-insoluble molecules move by the lipid layer of membranes. Plants also have such a detoxification system that helps counterbalance the phytotoxicity effects caused by a wide range of natural and synthetic xenobiotics present in the environment (Zhang and Yang 2021). Chemical modification of xenobiotics is one of the important detoxification mechanisms.
A dietary intervention in Bangladesh to counteract arsenic toxicity
Published in Yong-Guan Zhu, Huaming Guo, Prosun Bhattacharya, Jochen Bundschuh, Arslan Ahmad, Ravi Naidu, Environmental Arsenic in a Changing World, 2019
J.E.G. Smits, R.M. Krohn, A. Vandenberg, R. Raqib
Arsenic levels in hair, stool and urine samples are measured by Hydride Generation Atomic Absorption Spectrometry (HGAAS). Oxidative stress and antioxidant status is determined by measuring 8-OHdG, a major product of ROS-induced oxidative stress, in urine and plasma using ELISA kits. Selenium-dependent glutathione peroxidase uses to scavenge reactive oxygen species (ROS), resulting in the production of oxidized GSSG (33). The antiox-idant status based on reduced glutathione (GSH) and the oxidized form, GSSG, is determined by the ratio of GSH:GSSG using an ELISA. Triglyceride, total cholesterol, high-density-lipoprotein (HDL), and low-density-lipoprotein (LDL)-cholesterol plus acute phase proteins are measured using a Biochemistry Analyzer Cobas c 311.
Lead Toxicity and Flavonoids
Published in Tanmoy Chakraborty, Lalita Ledwani, Research Methodology in Chemical Sciences, 2017
Amrish Chandra, Deepali Saxena
Antioxidants are compounds that protect cells against the damaging effects of ROS, such as singlet oxygen, superoxide, peroxyl radicals, hydroxyl radicals, and peroxynitrite. An imbalance between antioxidants and ROS results in oxidative stress, leading to cellular damage. Oxidative stress has been linked to cancer, aging, atherosclerosis, ischemic injury, inflammation, and neurodegenerative diseases (Parkinson's and Alzheimer's). Flavonoids may help provide protection against these diseases by contributing, along with antioxidant vitamins and enzymes, to the total antioxidant defense system of the human body. Epidemiological studies have shown that flavonoid intake is inversely related to mortality from coronary heart disease and to the incidence of heart attacks. However, recent studies have demonstrated that flavonoids found in fruits and vegetables may also act as antioxidants.73
Antioxidant and cytoprotective effects of sequentially extracted Terminalia prunioides pods
Published in Egyptian Journal of Basic and Applied Sciences, 2023
Phazha Baeti, Keagile Bati, Kabo Masisi, Goabaone Gaobotse, Tebogo Kwape
The body has antioxidants as an adaptation response to the prevention, and to lessen the adverse consequences of oxidative stress. When present in small amounts, antioxidants, which are chemicals and proteins that significantly slow down or stop oxidative damage, can protect cells from oxidants [8,9]. Endogenous antioxidants, such as non-enzymatic reduced glutathione (GSH), enzymatic superoxide dismutase (SOD), and enzymatic catalase (CAT), serve as the body’s first line of defense [10,11]. In many circumstances, the physiologically necessary quantities of endogenous antioxidants alone are insufficient to properly protect cells [12]. Considering this, exogenous antioxidant supplements are necessary to augment the endogenous antioxidant system. Superoxide anion is reduced by SOD into diatomic oxygen and hydrogen peroxide [13]. Hydrogen peroxide is converted by catalase (CAT) into water and, occasionally, hydroxyl anion through the Fenton reaction [14]. Hydroxyl radical is reduced by GSH to water [15]. GSH is reduced to GSSG (oxidized GSH) as a result of the hydroxyl radical reaction [16]. In order to convert back GSSH into GSH, it needs either electron and/or hydrogen atom donors. Exogenous antioxidants from medications and plants have been demonstrated in studies to convert GSSH to GSH by electron and hydrogen reduction [17]. It has been discovered that bioactive compounds extracted from plants are efficient free radical reducing agents through several mechanisms such as hydrogen atom transfer (HAT) and single electron transfer (SET) [18].
Methanolic fraction of Cassia fistula L. bark exhibits potential to combat oxidative stress and possess antiproliferative activity
Published in Journal of Toxicology and Environmental Health, Part A, 2023
Rasdeep Kour, Neha Sharma, Sheikh Showkat, Sunil Sharma, Kommu Nagaiah, Subodh Kumar, Satwinderjeet Kaur
It is noteworthy that living organisms are equipped with the ability to counter the adverse effects of ROS by employing antioxidant enzymes including catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD). As these protective mechanisms become unbalanced due to certain pathological conditions, the use of antioxidant supplements is considered as a therapeutic source crucial to combat oxidative stress (Li et al. 2021; Poljsak, Šuput, and Milisav 2013; Prasad, Gupta, and Tyagi 2017). The possible antioxidant protective mechanisms of action against ROS are conversion of reactive metabolites into stable or less reactive molecules, scavenging reactive species to prevent ROS formation and bioaccumulation and subsequently block ROS-mediated attack on biomolecules (Barzegar, Moosavi-Movahedi, and Calixto 2011). Currently, the development of ethnomedicines with low cytotoxicity and potent antioxidant properties is gaining more attention (Batista et al. 2022; deSousa et al. 2019; Kola et al. 2022; Kramberger et al. 2021).
Urinary concentrations of amphenicol antibiotics in relation to biomarkers of oxidative DNA and RNA damage in school children
Published in Journal of Environmental Science and Health, Part A, 2022
Yang Geng, Man Hu, Yuan Yao, Ming Zhan, Ying Zhou
Oxidative stress damages cellular and tissue biomolecules and is involving in the development of numerous diseases.[18–20] Increasing evidences from in vitro and in vivo studies suggested that the adverse health effects of CAP and its analogues may be linked to oxidative stress.[21,22] Previous studies have stated clearly that exposure to CAP and/or TAP could induce oxidative stress responses in Daphnia magna[17] and in human neutrophils.[23] Animal studies also found that FF exposure promoted oxidative stress through inhibiting the expression of related factors in nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway and resulted in the hepatocyte apoptosis in broilers[24] as well as excessive apoptosis of renal cells in chicks.[25]