MFN1 and Alzheimer disease: Similar to its effects on AD, Aβ1–42 induces neuronal apoptosis by concurrently upregulating mitochondrial fission protein dynamin-related protein 1 (Drp1) and downregulating mitofusin 1/2 (Mfn1/2) and dynamin-like GTPase (OPA-1) in primary cultures of mouse cerebral cortical neurons (Han et al., 2017).