Question

Free radicals and their role in lipid peroxidation

Answer 1

Lipid peroxidation has been implicated in the pathogenesis of various disorders and diseases. Free and ester forms of unsaturated fatty acids and cholesterol are important substrates, and they are oxidized by three distinct mechanisms, namely, free radical-mediated chain reaction, enzyme-mediated oxidation, and nonradical, nonenzymatic oxidation. Each oxidation gives specific products. Furthermore, each oxidation mechanism requires specific antioxidant to inhibit. Lipid peroxidation induces disturbance of membrane fine structure and loss of functions, and it modifies low-density lipoprotein to proatherogenic forms. Lipid peroxidation products are often toxic and modify proteins and DNA bases. Many studies show the elevation of lipid peroxidation products with the progress of diseases, although it has not been elucidated clearly whether lipid peroxidation plays a causal role in the pathogenesis of diseases or it is a consequence of diseases.