However, compared to saline-treated control PD brains, in animals treated with sEV-SR3677, the gene Opa1, which encodes the optic atrophy protein 1 (OPA1) that plays a crucial role in mitochondrial structure, fusion, and stability, and Timm9, which encodes a protein that inserts proteins into the mitochondrial inner membrane, were upregulated by 1.7-fold and 2-fold, respectively. The gene discussed is TIMM9; the disease is Parkinson disease.