PTPN1 and Alzheimer disease: However, levels of miR-124 have been found to be either reduced or elevated in AD brain (Wang et al., 2022; Zhang W. et al., 2023), but in agreement with our findings of increased miR-124a in male 5xFAD, miR124 levels were found to be increased in hippocampus of AD subjects and the Tg2576 AD mouse model (Wang X. et al., 2018), in which miR-124 was shown to target the tyrosine-protein phosphatase non-receptor type 1 (PTPN1).