FYN and Alzheimer disease: Furthermore, given the key role that Fyn may play in the upregulation of microglial and astrocytic activation, Fyn kinase may represent a universal target, not only in AD and PD but also across multiple conditions known to be associated with a chronic neuroinflammatory response, including amyotrophic lateral sclerosis (ALS) (Liu and Wang, 2017), stroke (Zhang W. et al., 2021), traumatic brain injury (Schimmel et al., 2017) and status epilepticus (Sharma et al., 2021).