GFAP and Parkinson disease: To better understand inflammatory changes in the retina, as a part of the broader spectrum of PD neuropathological processes regulated by SIRT1 and α-Syn accumulation [41, 42], we evaluated the extent of retinal macroglia and microglia activation by assessing the expression of glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (Iba-1), respectively.