Miroestrol, a phytoestrogen from Pueraria mirifica, improves the antioxidation state in the livers and uteri of β-naphthoflavone-treated mice.

Oxidative stress is involved in the progression of several diseases such as diabetes, hypertension, and age-related diseases. Miroestrol (MR) is a potent phytoestrogen from the tuberous root of Pueraria mirifica, a plant used in traditional Thai medicine that is claimed to have rejuvenating effects. In this study, the effects of MR on the antioxidation system, including anti-lipid peroxidation; on the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase; and on glutathione content in the livers and uteri of β-naphthoflavone (BNF)-treated mice were determined. BNF-treated mice are a model of procarcinogen-exposed mice. The results showed that MR improved the antioxidant activities of SOD and CAT in the livers and uteri of both normal and BNF-treated mice, while estradiol (E2) increased SOD activity in the uteri of normal mice and CAT activity in the livers of both normal and BNF-treated mice. In the liver, MR increased the levels of several forms of glutathione, whereas in the uteri E2 and MR reduced the level of lipid peroxidation by decreasing the level of malondialdehyde. Therefore, the use of MR as an alternative hormone replacement therapy might be beneficial due to its ability to improve antioxidation systems.