Volume: 2 Issue: 3
Year: 2025, Page: 108-114, Doi: https://doi.org/10.71325/ajjms.v2i3.2 5.49
Received: Sept. 30, 2025 Accepted: Oct. 10, 2025 Published: Nov. 15, 2025
Oxidative stress, an imbalance between pro-oxidant agents and antioxidant agents in which the pro-oxidant agents exceed the antioxidant concentration, has become a pivotal mechanism in the onset and advancement of several human illnesses. Although physiologically crucial for cellular communication, immune defense, and adaptability, excessive oxygen radical production surpasses antioxidant capability, leading to biomolecular damage and malfunction. This study seeks to thoroughly analyze the processes that induce oxidative stress in the human body, highlighting both endogenous and external sources, along with the complex association between oxygen radicals and the production of pro-inflammatory cytokines. Endogenous factors include mitochondrial electron leakage, NADPH oxidase activity, endoplasmic reticulum stress, peroxisomal metabolism, xanthine oxidase activity, cytochrome P450 uncoupling, and transition metal-mediated Fenton chemistry. Exogenous inducers, including cigarette smoke, air pollution, heavy metals, alcohol, food excess, psychological stress, and xenobiotic exposure, exacerbate oxidative stress, frequently interacting synergistically with endogenous processes. Simultaneously, inflammatory processes emerge not only as a result of reactive oxygen radical but also sustain their generation via cytokine signaling, NF-κB activation, inflammasome assembly, and the synthesis of peroxynitrite from nitric oxide, establishing a detrimental cycle of oxidative-inflammatory injury.
Keywords: Antioxidant defenses, Endogenous and exogenous stressors, Inflammatory pathways, Oxidative stress, Reactive oxygen species (ROS)
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© 2025 Published by Laxmi Memorial Education Trust. This is an open-access article under CC BY 4.0 license. (https://creativecommons.org/licenses/by/4.0/)
Ali Faris Hassan, Nada Naji Al-Shawi, Rita Fayyadh Elia. Mechanisms of Oxidative Stress in the Human Body: A Review. AJ J Med Sci 2025;2(3):108-114