Superoxide dismutase activity in lung from copper- and manganese-deficient mice exposed to ozone.
Nutritional manganese (Mn) or copper (Cu) deficiency was investigated in Swiss-Webster mice exposed to ozone (O3). Mice rendered Mn-deficient were first reared from Mn-deficient dams and then fed a Mn-deficient (1 microgram/g) diet. Mice rendered Cu-deficient were fed a diet containing 0.2 microgram Cu/g diet. Control mice were fed a diet containing Mn at 45 micrograms/g and Cu at 8 micrograms/g. During the last week of the experiment (week 7, post-weanling), mice in each group were exposed continuously to 1.2 ppm O3 or filtered air for 7 days. Superoxide dismutase (SOD) activity in lung was then estimated. In mice breathing filtered air, neither lung Cu,Zn- nor Mn-SOD activity (U/g) was affected by diet. In O3-exposed mice, however, Mn-SOD activity was lower in the Mn-deficient group and Cu, Zn-SOD activity was lower in the Cu-deficient group. Moreover, total lung Cu,Zn-SOD activity was elevated in the Mn-deficient mice, whereas total Mn-SOD activity was elevated in the Cu-deficient mice in response to O3. These data indicate that under normal circumstances lung Cu,Zn-SOD and Mn-SOD are not affected by Cu or Mn deficiency. However, when an oxidant stress is superimposed on the Cu- or Mn-deficient condition, Cu,Zn- and Mn-SOD activities are impaired.
Dubick
M A
MA
Division of Military Trauma Research, Letterman Army Institute of Research, Presidio of San Francisco, CA 94129.
Zidenberg-Cherr
S
S
Rucker
R B
RB
Keen
C L
CL
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003300:Copper / Q000032:analysis / Q000172:deficiency*; D005260:Female; D007501:Iron / Q000032:analysis; D008168:Lung / Q000032:analysis / Q000201:enzymology*; D008297:Male; D008345:Manganese / Q000032:analysis / Q000172:deficiency*; D051379:Mice; D009929:Organ Size / Q000187:drug effects; D010126:Ozone / Q000633:toxicity*; D013482:Superoxide Dismutase / Q000037:antagonists & inhibitors*; D015032:Zinc / Q000032:analysis
D008345:Manganese; D010126:Ozone; D003300:Copper; D007501:Iron; D013482:Superoxide Dismutase; D015032:Zinc