Diabetes mellitus (DM) is a serious health concern that affects millions of
people worldwide. Despite numerous studies on the topic, the exact mechanisms
underlying diabetes progression and its complications is still unclear. Growing
evidence suggests that hyperglycemia results in increased reactive oxygen species
(ROS) production, leading to oxidative stress which affects and damages various
tissues and organs. Oxidative stress results from an imbalance between ROS and
antioxidants. During cellular metabolism free radicals such as ROS and reactive
nitrogen species (RNS) are produced, and these free radicals have dual effects (both
positive and negative) on nearby tissues and activate several oxidative stress-related
signaling pathways. Oxidative stress has been identified as a major player in the
pathogenesis of diabetes and its associated complications such as stroke, neuropathy,
retinopathy, peripheral vascular disease, nephropathy and lower limb ulceration.
Oxidative stress damages the surrounding tissue, and the effects continue for extended
periods even after blood glucose concentrations return to normal. Prolonged oxidative
stress results in insulin resistance, β-cell dysfunction, glucose intolerance and
mitochondrial damage. Antioxidants are a group of enzymatic or non-enzymatic
molecules that encounter and neutralize free radicals, thereby protecting the body from
oxidative stress. Many exogenous molecules such as antioxidant supplements, vitamins
(vitamin C and E) and metal ion chelators detoxify free radicals and maintain
physiological levels. A better understanding of the involvement of oxidative stress in
the pathogenesis of diabetes could have major therapeutic implications for treatment.
An effective approach to treat oxidative stress is by using exogenous drugs that mimic
antioxidants. Overall, this chapter highlights the understanding of oxidative stressrelated
mechanisms underlying the development of diabetes. It also elaborates on
antioxidant therapy strategies to diminish oxidative stress and to treat diabetic
associated complications.
Keywords: Antioxidants, Catalase, Diabetes, Free radicals, Glutathione,
Hyperglycemia, Oxidative stress, Reactive oxygen species, Reactive nitrogen
species, Superoxide dismutase.
