Uma Revisão sobre Estresse Oxidativo e morte celular
The intricate phenomenon of aging has generated a myriad of hypotheses over time. Modern gerontologists have a new conception where aging is defined as an adaptive process, not caused only by simple factors or processes, but by a multifactorial process modulated by the interaction between genetic and environmental factors. The most widely held cause of aging is the popular concept that the root cause of aging is oxidative stress. However, this concept can be interpreted in numerous ways. The free radical theory of aging gained credibility with the identification in 1969 of the enzyme superoxide dismutase (SOD), which provided the first compelling evidence for the in vivo generation of superoxide anion (O2- •). subcellular processes of O2- • generation, led to the strengthening of the aforementioned theory, indicating that mitochondria are the main source of endogenous oxidants. The term oxidative stress derives significantly from the basic force that extracts oxidation through its oxidizing power, oxygen, an element essential for supporting aerobic metabolism and life. Numerous studies document a clear relationship between oxidants and changes in structures and functions, at all levels, molecular, cellular, tissue, systems and organs. Molecular studies carried out with oxidative stress have shown that there is a change in gene regulation during aging, a fact that proves the inseparable nature of oxidative stress at the genetic level. However, although damage accumulation and genetic modulation are considered excellent markers of the effects of stress, they do not represent the direct cause of aging. To better understand these processes, a review was carried out in this article covering the types of oxidizing agents that cause oxidative stress in human cells and the relationship between this phenomenon and aging and death. Defense mechanisms against oxidizing agents have also been reported.
Keywords: Reactive Oxygen Species. Antioxidative enzymes. Non-enzymatic antioxidant system. Aging.
_________________________
1Professora aposentada do Centro de Ciências da Saúde da Universidade Estadual do Ceará. Governo do Estado do Ceará, Brasil. Doutora em Bioquímica e Biologia Molecular pela Universidade Federal do Ceará, Brasil.
2Graduando do Curso de Nutrição do Centro de Ciências da Saúde da Universidade Estadual do Ceará, Brasil.
