Título del libro: Handbook Of Free Radicals: Formation, Types And Effects
Título del capítulo: Free radicals: Formation, types and effects in central nervous system
MATEO HUGO JUAREZ OLGUIN;
Autores externos:
Idioma:
Inglés
Año de publicación:
2010
Resumen:
Free radicals (FR) have an important function in several homeostatic processes. They act as intermediate agents in essential oxidation-reduction (redox) reactions. An example is the synthesis of detoxification compounds. FR in low concentrations are useful and even essential, however, in high concentrations they are toxic. If biological molecules are oxidized, they are altered and can trigger of cellular metabolism disorder. Every organism counts with an antioxidant (AO) protective system that limits damage caused by FR. This protective system includes enzymes and pharmacological therapies that inhibit FR generation, trap down those that already exist and depurate or repair damaged biomolecules. The AO system and the generation of FR coexist in a balanced way. When this equilibrium is altered the result will be oxidative stress, which could provoke cell injury, trigger off physiologic disorders and promote pathologic processes. A FR represents any chemical species that exists independently and has one or more unmatched electrons rotating in its external atomic orbits. This highly unstable configuration makes this chemical species to be very aggressive and confers it a shorter life span. There is an inverse correlation between the magnitude of this reactivity and its life span as well as its ability to diffuse through cells. Chemically, a FR can be generated in different pathways, but the most frequent in living organisms is the addition of an electron to a stable molecule. Several authors have classified FR according to the functional group in their molecule. The most frequent is an oxygen FR, in which oxygen is the functional center. Thiol radicals contain sulfur and other radicals contain carbon, phosphorus or nitrogen in their respective groups. Most FR is generated from normal metabolic reactions, and exogenous factors can increase them, reason why it is necessary the study of the neurochemical mechanisms on the central nervous system (CNS) in animal models. Due to the importance of this topic in human beings, this chapter reviews the updated knowledge on FR and its possible mechanisms in neurological disorders and in some oxidative stress processes including oxidative markers available for evaluating the consequences of such damage using new pharmacological therapies. © 2010 by Nova
Entidades citadas de la UNAM:
ISBN:
9781608761012
Editorial:
Nova Science Publishers, Inc. Nombre de la publicación:
Free radicals: Formation, types and effects in central nervous system
Página inicial:
539
Página final:
556
Tipo de producto:
Capítulo de un Libro
