Abstract:Objective To study the effects of antioxidant mitoquinone (MitoQ) on blood pressure and placental mitochondrial dysfunction in the rat model of preeclampsia, and to explore the underlying mechanisms.Methods A total of 30 rats with preeclampsia were randomly divided into preeclampsia group, MitoQ group, and MitoQ + brusatol group, with 10 rats in each group. In addition, another 10 SD rats were selected as the control group. On the 14th day of gestation, rats in the MitoQ group were intraperitoneally injected with MitoQ at a dose of 3.5 mg/kg. The rats in the MitoQ + brusatol group were intraperitoneally injected with MitoQ at a dose of 3.5 mg/kg, and administered intragastrically with brusatol at a dose of 1 mg/kg. The rats in the control group and preeclampsia group were injected intraperitoneally and intragastrically with the same amount of normal saline once a day until the 19th day of gestation. The systolic blood pressure on the 15th, 17th, and 19th days of gestation was measured. The mitochondrial permeability transition pore (PT) activity was determined via colorimetry. The expression of nuclear factor E2-related factor 2 (Nrf2) and antioxidant response element (ARE) in placenta tissues were detected by Western blotting.Results There was no difference in systolic blood pressure at different time points (F = 0.045, P = 0.963). The systolic blood pressure (F = 15.111, P = 0.000) and the changing trend thereof (F = 16.889, P = 0.000) were different among the groups. The PT activity in the preeclampsia group was higher than that in the control group and MitoQ group (P < 0.05). Compared with the MitoQ group, the PT activity in the MitoQ + Brusatol group was also higher (P < 0.05). The placental expression of Nrf2 and ARE proteins in the preeclampsia group was lower than that in the control group and MitoQ group (P < 0.05). In addition, the placental expression of Nrf2 and ARE proteins was lower in the MitoQ + Brusatol group relative to the MitoQ group (P < 0.05).Conclusions The antioxidant MitoQ can lower the blood pressure of rats with preeclampsia and improve the placental mitochondrial function and structure. Its therapeutic effects may be achieved by regulating the Nrf2/ARE pathway.