A mitochondrial regulator protein, mitofusin 2, is elevated in the maternal blood of women with preeclampsia.

Objective: To investigate the expression of mitofusin 2 (Mfn2) in the placenta and peripheral blood of patients with early-onset preeclampsia (eoPE) and late-onset preeclampsia (loPE), and to evaluate its possibility as a diagnostic and therapeutic target for preeclampsia.

Methods: A total of 68 pregnant women with preeclampsia in Jiaxing Maternal and Child Health Hospital from June 2022 to June 2024 were selected, including 32 patients with eoPE and 36 patients with loPE, and 68 term pregnant women as negative controls. Real-time fluorescence reverse transcription (RT-qPCR) was used to determine the expression level of Mfn2 mRNA in placenta and peripheral blood, and the expression of Mfn2 was analyzed; enzyme-linked immunosorbent assay (ELISA) was used to determine the level of Mfn2 in peripheral blood of patients, and the outcomes of pregnant women (placental weight, neonatal birth weight, 1 min Apgar) were recorded. The correlation between the level of Mfn2 in peripheral blood and the severity of preeclampsia and pregnancy outcomes was analyzed.

Result: The expression of Mfn2 mRNA in the placenta tissue of the eoPE group was significantly lower than that of the term pregnancy group and the loPE group (P < 0.001), while the expression of Mfn2 in the placenta tissue of the loPE group was only lower than that of the term pregnancy group, with no significant difference(P > 0.05). The expression of Mfn2 mRNA in the peripheral blood of eoPE and loPE was significantly higher than that of term pregnancy group (all P < 0.001). In the peripheral blood, the levels of Mfn2 in eoPE group and loPE group were significantly higher than that of the term pregnancy group (all P < 0.001). The Pearson correlation analysis showed that the expression level of Mfn2 protein in peripheral blood of patients are positively correlated with blood pressure and urinary protein, and negatively correlated with neonatal birth weight and 1 min Apgar score.

Conclusion: In early-onset placenta, the expression of Mfn2 is significantly lower than that in full-term pregnancy, while in late-onset eclampsia, it is not, indicating that the abnormal expression of Mnf2 in placenta is related to the occurrence period of preeclampsia and the progression of the disease; Mfn2 in peripheral blood can be used as a biological marker to evaluate the occurrence and progression of preeclampsia.