Estrogen effects on NADH oxidase and superoxide dismutase i prepubertal female rats

Thirty-four day old, ovariectomised rats were treated with increasing doses of estradiol, 2-hydroxyestradiol 2,3-dimethyl ether (23E2), 4-hydroxyestradiol 3,4-dimethyl ether (34E2) and 4-methoxyestradiol (4ME2) for five days by subcutaneous injection. Superoxide dismutase, phenol activated NADH oxidase and uterine dry weights were determined. Only estradiol was found to be uterotrophic and increased NADH oxidase activity in these experiments. Both 23E2 and 34E2 treatment reduced the enzyme activity significantly. Though 4ME2 showed a decrease in NADH oxidase at 0.05 micrograms/100 gm body weight there was no further decrease at higher dose (5 micrograms/100 gm). The superoxide dismutase (SOD) in uterus and liver was unaffected by estradiol, while 23E2, 34E2, and 4ME2 significantly reduced SOD in both liver and uterus. These results indicate that 23E2, 34E2 and 4ME2, in spite of their nonuterotrophic property property, affect uterine metabolism. Furthermore, in view of the reports indicating the importance of SOD levels in various tumors and since catecholestrogens are observed to reduce SOD levels in liver and uterus, it is suggestive that catecholestrogens may play an important role in the pathophysiology of certain tumors.