There’s something in (1), but it doesn’t address the entire spectrum of Harmala alkaloid neurotoxicity (2) (3). It has been shown that heterocyclic aromatic amines (which Harmala alkaloids belong to) indeed damage dopaminergic neurons (4).

(1): https://hammer.purdue.edu/articles/thesis/Identification_of_... (2): https://onlinelibrary.wiley.com/doi/pdf/10.1002/ijc.20703 (3): https://www.sciencedirect.com/science/article/pii/S157002320... (4): https://academic.oup.com/toxsci/article-abstract/173/1/171/5...