Define oxidative damage.

• A. Damage to DNA
• B. Damage to brain proteins
• C. Lipid peroxidation
• D. Free radical formation

Answer: (B)

Oxidative damage happens when reactive oxygen species attack and harm cellular components. These reactive molecules can modify and impair proteins, lipids, and DNA. In many contexts, damage to brain proteins is a prominent example because the brain uses a lot of oxygen and contains many susceptible proteins; when ROS modify these proteins, it can disrupt enzyme activity, signaling, and structural integrity, contributing to neural dysfunction.

While damage to DNA or lipid peroxidation are also forms of oxidative damage, and free radical formation is a source that leads to this damage, the option focusing on brain proteins best represents a concrete outcome of oxidative stress in a physiological setting.