Mito-TEMPO protects preimplantation porcine embryos against mitochondrial fission-driven apoptosis through DRP1/PINK1-mediated mitophagy

• DOI: 10.1016/j.lfs.2022.121333
• Publication Date: 2023-01-03T16:11:27Z
• Authors: Seul-Gi Yang; Jin-Wook Bae; Hyo-Jin Park; Deog-Bon Koo
• Keywords: Dynamins; 0301 basic medicine; 03 medical and health sciences; Blastocyst; Swine; Superoxides; Mitomycin; Mitophagy; Animals; Apoptosis; Mitochondrial Dynamics; Protein Kinases

Mdivi-1 (Md-1) is a well-known inhibitor of mitochondrial fission and mitophagy. The mitochondrial superoxide scavenger Mito-TEMPO (MT) exerts positive effects on the developmental competence of pig embryos. This study aimed to explore the adverse effects of Md-1 on developmental capacity in porcine embryos and the protective effects of MT against Md-1-induced injury.We exposed porcine embryos to Md-1 (10 and 50 μM) for 2 days after in vitro fertilization (IVF). MT (0.1 μM) treatment was applied for 4 days after exposing embryos to Md-1. We assessed blastocyst development, DNA damage, mitochondrial superoxide production, and mitochondrial distribution using TUNEL assay, Mito-SOX, and Mito-tracker, respectively. Subsequently, the expression of PINK1, DRP1, and p-DRP1Ser616 was evaluated via immunofluorescence staining and Western blot analysis.Md-1 compromised the developmental competence of blastocysts. Apoptosis and mitochondrial superoxide production were significantly upregulated in 50 μM Md-1-treated embryos, accompanied by a downregulation of p-DRP1Ser616, PINK1, and LC3B levels and lower mitophagy activity at the blastocyst stage. We confirmed the protective effects of MT against the detrimental effect of Md-1 on blastocyst developmental competence, mitochondrial fission, and DRP1/PINK1-mediated mitophagy activation. Eventually, MT recovered DRP1/PINK1-mediated mitophagy and mitochondrial fission by inhibiting superoxide production in Md-1-treated embryos.MT protects against detrimental effects of Md-1 on porcine embryos by suppressing superoxide production. These findings expand available scientific knowledge on improving outcomes of IVF.