Aging modifies the circadian expression of antioxidant enzymes in cerebellum

CASTRO PASCUAL, IVANNA CARLA; ALTAMIRANO, FERNANDO GABRIEL; LACOSTE, MARÍA GABRIELA; ANZULOVICH, ANA CECILIA; FERRAMOLA, MARIANA LUCILA

Mar del Plata

Congreso; XXX Reunión Anual de la Sociedad Argentina de Investigación en Neurociencias; 2015

Sociedad Argentina de Investigación en Neurociencias

Cerebellum functions decline in older adults and are susceptible to oxidative stress. Previously, we observed oscillating 24h-patterns of catalase (CAT) activity and GSH levels are modified in the cerebellum of aged rats. The objectives of this study were: 1) to analyze the CAT and GSH peroxidase 4 (GPX4) expression as well as the clock factor, BMAL1, protein levels throughout a 24h period in the rat cerebellum and 2) to investigate whether circadian rhythms of antioxidant enzymes and BMAL1 are modified in aged rats. Holtzman rats from young (3-months old) and aged (22-months old) groups were maintained under constant darkness conditions, during 15 days before the experiment. CAT and GPx4 mRNA as well as BMAL1 protein levels were determined in cerebellum samples isolated every 4 h during a 24h period. We observed BMAL1 protein vary significantly throughout a 24h period in young and aged rats. However, aging phase shifted BMAL1 protein rhythmicity (CT 08:48±00:42 vs CT 18:02±01:05,p˂0,001 and reduced the rhythm mesor (0,97±0,001 vs 1,07±0,008,p˂0.001). We also observed GPx4 mRNA circadian rhythm. In this case,aging reduced the rhythm´s mesor (1,37±0,04 vs 1.87±0.03,p˂0.001). However, we didn´t observe a 24h- variation in CAT expression, neither in young or aged animals. Aging affects circadian rhythms of antioxidant enzymes and BMAL1 clock factor in a different way. This might indicate other factors are mediating circadian regulation of antioxidant enzymes expression.