The components of ECM in the brain include basement membranes (BM) surrounding cerebral vessels and perineuronal nets (PN), as well as neural interstitial matrix (NIM).14 The macromolecules from the PN and NIM, such as tenascin R and proteoglycan, have been studied in the context of neurodegeneration due to their maintenance features.14, 15, 16 In terms of age‐related AD pathology, however, little attention has been paid to the fibrous proteins (for example, elastin) in the BM region. Here, ELN is linked to Alzheimer disease.