Evaluation of selected parameters of oxidative stress in patients with alopecia areata

Alopecia areata (AA) is a form of non-scarring hair loss with immune background. In parallel with the major disorders that constitute the criteria for diagnosis of AA, there are usually many other abnormalities, including oxidative-antioxidative balance disorders, which are of pathophysiological and clinical importance and provide the basis for making both preventive and therapeutic decisions [1, 2].
Reactive oxygen species (ROS) are molecules functioning as secondary cellular transmitters which are formed during the physiological processes of cellular metabolism. Released in small amounts, they act as mediators and regulators of metabolism. Many factors affecting the cell contribute to an increased generation of ROS, and changes in their concentration inside the cell, affect the expression of antioxidant enzyme genes, acute-phase proteins, cytokines and their receptors, growth factors and genes of cell adhesion proteins [3].
Insufficiency of defense systems and an increase in free radical levels leads to prooxidant-antioxidant imbalances and, consequently, to inducing oxidative stress [4]. Polyunsaturated fatty acids that are part of phospholipids are particularly susceptible to oxidation. It is a chain process where the key product is malondialdehyde (MDA), commonly used as an indicator of oxidative lipid damage. Oxidation products of the lipid component of cell membranes lead to lower hydrophobicity of lipid cell interior, changes in membrane receptor function and double lipid layer organization, and in consequence, to disorders of their lipid asymmetry and loss of integrity of cell membranes [3, 5].
Reactive forms of oxygen are also responsible for the oxidative modifications of proteins (AOPPs). Dityrosine, carbonyl groups and cross bonds are most abundant in the structure of AOPPs. Physiologically AOPPs are formed throughout life, with a slightly increasing intensity with age. An increase in their concentration has been observed in some pathological conditions accompanied by inflammation [6].
The objective of this study was to evaluate the oxidant-antioxidant balance in patients with AA by assessment of the activity of paraoxonase 1 (PON1), the level of malondialdehyde (MDA) and advanced oxidation protein products (AOPPs) in patients with AA. The study included 30 AA patients (23 females/8 males, mean age: 34.4 ±10.9) and the control group consisting of 30 age- and sex-matched healthy volunteers (17 females/13 males,...


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