Resumo

SIERRA VARGAS, Martha Patricia et al. Increase of myeloperoxidase activity in patients with asthma associated to diabetes mellitus type 2. An indicator of homeostatic disequilibrium. Rev. Inst. Nal. Enf. Resp. Mex. [online]. 2006, vol.19, n.3, pp.201-205. ISSN 0187-7585.

Background: The activity of the enzyme myeloperoxidase (MPO, EC 1.11.1.7), in plasma has been related to several chronic-degenerative diseases such as asthma and diabetes mellitus which have in common a chronic inflammatory condition. Several reactive species of oxygen are generated during inflammation, including hypochlorous acid, which is a product of MPO. Objective: To prove that asthma and diabetes mellitus, in which there is oxidative stress, present a cumulative metabolic response that can be measured by an increase of MPO, as a marker of oxidative damage. Methods: The activity of MPO was measured in the plasma of a control group of 31 healthy volunteers and in three groups of patients: a) 13 asthmatics, b) 29 diabetics, c) 6 asthmatics and diabetics. Results: In patients with both diseases, asthma and diabetes mellitus, there was a significant increase in the activity of the enzyme MPO (65.1 ± 11.2 U*; p < 0.05). The activity of MPO was similar in the control group (37.6 ± 3.2 U*), the asthma group (35.9 ± 5.2 U*) and the diabetics (32.6 ± 3.3 U*). Conclusions: The coexistence of asthma and diabetes mellitus, both chronic-degenerative diseases, increases the possibility of tissue damage due to the generation of oxygen reactive species that overwhelms the antioxidant defenses of the body, augmenting the oxidative stress and inducing secondary tissue damage and homeostatic disequilibrium. *U= U/mg of protein

Palavras-chave : MPO; asthma; diabetes mellitus; oxidative stress.