Representative images of dopaminergic neurons in the zebrafish brain, acquired using TH immunostaining. (A) Ginkgo biloba dropping pills (GBDP) prevented the loss of dopaminergic neurons induced by 6-OHDA. The red arrow shows dopaminergic neurons in the zebrafish brain. (B) The area of the dopaminergic neurons calculated for each group. ### p < 0.0001 vs. the control group; * p < 0.05 and ** p < 0.001 vs. the 6-OHDA group (n = 10 per group). (C) HE staining of brain sections of an MPTP-induced mouse model of Parkinson’s disease. The black arrow indicates significant diminished and loose nerve fiber components, which are lightly stained, while the yellow arrow shows intensive staining of the nuclei of several atrophied cells. Glial cells exhibited modest hyperplasia, as shown by the green arrow. (D,E) In MPP-treated human SH-SY5Y cells, GBDP administration reduced the Bax/Bcl-2 ratio and elevated Akt/GSK3β. ### p < 0.0001 vs. the MPP+ group. Adapted with permission from [152]. Copyright {2021} Science-HHS Public Access (PubMedCentral).