EFFECT OF AGE ON ALTERATION OF GLUTATHIONE METABOLISM FOLLOWING CHRONIC CIGARETTE-SMOKE INHALATION IN MICE

Cigarette smoke is the most common oxidant stress in daily life and ma y affect the antioxidant capacity in humans and animals. The antioxida nt functions may play an important role in preventing age-related diso rders. However, influences of chronic cigarette smoke on the antioxida nt capacity of visceral organs have not been investigated in the age. Senescene-accelerated mice (SAM) are good models for studying physiolo gic and/or pathologic aging. A senescene-prone strain, SAMP2, shows ch aracteristics of premature aging. The senescence-resistant strain, SAM R1, exhibits relatively normal aging. In this study we examined the ef fects of chronic cigarette smoke exposure on the glutathione (GSH) met abolism of visceral organs in the two strains of mice that were 6 and 18 months old. After a 4-week cigarette or air exposure, total GSH and oxidized GSH (GSSG) in the organs were examined. In the young (6-mont h-old) mice, exposure to cigarette smoke caused a significant decrease of GSH in liver, blood, and lung of SAMP2 but not in those of SAMR1. In the aged (18-month-old) mice reduced GSH with a marked increase of GSSG were found in liver of both strains of SAM following cigarette sm oke exposure. The baseline values of GSH and the GSSG/GSH ratio after air exposure were slightly changed with age, and the values after expo sure to cigarette smoke were changed markedly with advancing age. Thes e results indicate that GSH metabolism may be impaired by chronic ciga rette smoke exposure in mice and that aged mice are more susceptible t o cigarette smoke than young mice.