TH and Parkinson disease: IHC of midbrain tissues (Figure 2A,B) showed that the number of TH+ cells was decreased in the MPTP group (188 ± 16.59 (Control) vs. 79.25 ± 12.58 (MPTP), p < 00001), indicating successful modeling, and increased after artemisinin treatment (143 ± 7.528 (Artemisinin) vs. 79.25 ± 12.58 (MPTP), p = 00002), indicating that the drug successfully ameliorated PD pathology.