MFN1 and Alzheimer disease: Here, we detected the expression of Ezrin and mitochondrial fission and fusion protein in the AD cell model and found that celastrol inhibited the activation of Ezrin, the phosphorylation of mitochondrial Drp1 at the Ser616 and the expression of Fis1, while up‐regulating the Mfn1 and Mfn2.