Low expression of Mfn2 is associated with mitochondrial damage and apoptosis in the placental villi of early unexplained miscarriage

Abstract Introduction Early miscarriage is the most common complication of pregnancy and in many cases the etiology is not clearly understood. We aim to profile the expression of Mfn2 and mitochondrial damage in villous tissues, in order to determine the underlying mechanism of unexplained miscarriage. Methods We investigated placental villous samples of 30 women with early unexplained miscarriage (miscarriage group) and 30 women with normal pregnancy (control group). Immunohistochemistry and western blotting were used to detect the Mfn2 expression. We observed trophoblastic cell apoptosis with TUNEL and analyzed Bcl-2 and Bax levels by western blotting. Transmission electron microscopy was used to analyze mitochondrial morphology and phosphomolybdic acid colorimetric method was used to measure the ATP content of all villous samples. Results Mfn2 staining showed extra-nuclear localization in the trophoblastic cells. Compared with the control group, the levels of Mfn2 and Bcl-2 were markedly decreased ( P