IBIMOL   23987
INSTITUTO DE BIOQUIMICA Y MEDICINA MOLECULAR PROFESOR ALBERTO BOVERIS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Oxidative stress markers in a glaucoma model
Autor/es:
FERREIRA, SANDRA; LERNER, FABIAN; EVELSON, PABLO; LLESUY, SUSANA
Lugar:
Montevideo, Uruguay
Reunión:
Congreso; V Meeting of the Society for Free Radical Biology and Medicine – South American Group; 2007
Institución organizadora:
Society for Free Radical Biology and Medicine – South American Group
Resumen:
Although it has been associated with high intraocular pressure, glaucoma is now considered as a multifactorial disease. The aim of this study was to evaluate the relationship between the development of glaucoma and oxidative stress. In order to assess the occurrence of oxidative stress, the following markers were evaluated: the total antioxidant capacity (TRAP), nitrite concentration and markers of lipid peroxidation (TBARS). TRAP was measured by chemiluminiscence. Nitrite concentration and TBARS were measured spectrophotometrically. Wistar rats (n=9) were operated and two epischeral veins were cauterized. In optic nerve head, TBARS values were 6.9 ± 0.5 nmoles/ mg protein* (7 days), 9.4 ± 0.4 nmoles/ mg protein* (15 days),  18.0 ± 1.2 nmoles/ mg protein* (30 days) 43.1 ± 5.3 nmoles/ mg protein* (60 days) (control value 1.9 ± 0.1 nmoles/ mg protein * p < 0.001). In vitreous humor of glaucomatous eyes TRAP values were 248 ± 24 µM Trolox (7 days),  240 ± 16 µM Trolox (15 days),   196 ± 14 µM Trolox (30 days)  92 ± 8 µM* Trolox (60 days) (control value 219 ± 24 µM Trolox *p < 0.01). In the aqueous humor of glaucomatous eyes TRAP values were 75 ± 7 µM Trolox* (7 days),  96 ± 14 µM Trolox* (15 days), 56 ± 9 µM Trolox* (30 days), 142 ± 7 µM Trolox* (60 days), (control value 192 ± 4 µM Trolox *p < 0.01). In optic nerve head nitrite concentrations were 37.0 ± 1.8 mM*  (7 days) 21.9 ± 0.8 mM*  (15 days), 57.6 ± 2.3 mM*  (30 days)  18.0 ± 0.9 mM* (60 days) (control value 9.5 ± 0.8 mM *p < 0.01). Reactive oxygen and nitrogen species were increased in glaucoma, this could be evidenced by the increased in lipid peroxidation and nitrite concentration. The decrease in the antioxidant levels may be a consequence of an increase in oxidative processes.