Oxidative Stress

Definition

Oxidative stresses refer to an imbalance between the production of reactive oxygen species (ROS) and the body’s ability to detoxify these reactive intermediates or repair the resulting damage. This condition can lead to cellular damage, affecting proteins, lipids, and DNA, which may contribute to the development of various diseases, including blood cancer, solid organ tumor, cardiovascular diseases, neurodegenerative disorders, and aging.

Importance of Understanding Oxidative Stresses

• Cellular Damage: Excessive oxidative stress can result in significant damage to cellular components, leading to impaired cell function and increased cell death.
• Disease Development: Oxidative stress is implicated in the pathogenesis of numerous diseases, making it a critical area of study for disease prevention and therapy.
• Aging Process: It is believed that oxidative stress plays a role in the aging process by contributing to the decline in cellular function over time.
• Therapeutic Targets: Understanding oxidative stress mechanisms can help identify potential therapeutic targets for antioxidant treatments aimed at mitigating damage.

Sources of Oxidative Stresses

Oxidative stress can arise from various sources, including:

• Endogenous Sources: Normal metabolic processes, such as mitochondrial respiration, produce ROS as byproducts.
• Exogenous Sources: Environmental factors such as pollution, radiation, cigarette smoke, and certain chemicals can increase ROS levels.

Antioxidant Defense Mechanisms

The body has several defense mechanisms to counteract oxidative stress:

• Enzymatic Antioxidants: Enzymes like superoxide dismutase (SOD), catalase, and glutathione peroxidase help neutralize ROS.
• Non-Enzymatic Antioxidants: Molecules such as vitamins C and E, glutathione, and flavonoids provide protection against oxidative damage.

Conclusion

Understanding oxidative stress is essential for recognizing its role in health and disease. By studying the balance between ROS production and antioxidant defenses, researchers can develop strategies to prevent or treat conditions associated with oxidative damage.

References

1. Sies H. Oxidative Stress: A Concept in Redox Biology and Medicine. Redox Biology. 2015; 4: 180-183. Available from: https://doi.org/10.1016/j.redox.2015.01.001
2. Halliwell B, Gutteridge JMC. Free Radicals in Biology and Medicine. 5th ed. Oxford University Press; 2015. Available from: https://global.oup.com/academic/product/free-radicals-in-biology-and-medicine-9780198717480
3. Cadenas E, Davies KJA. Mitochondrial Free Radical Generation, Oxidative Stresses, and Aging. Free Radical Biology and Medicine. 2000; 29(3-4): 222-230. Available from: https://doi.org/10.1016/S0891-5849(00)00222-0
4. Valko M, Leibfritz D, Moncol J, Cronin MT, Mazur M, Ruzicka R. Free Radicals and Antioxidants in Normal Physiological Functions and Human Disease. International Journal of Biochemistry & Cell Biology. 2007; 39(1): 44-84. Available from: https://doi.org/10.1016/j.biocel.2006.07.001