Catechol Tetrahydroisoquinolines Enhance a-Synuclein Aggregation andSpecify the Neurotoxicity to Dopaminergic Neurons

Parkinson disease (PD) is the second most common neurodegenerative disorder after Alzheimer disease with no definitive neuroprotective therapies. Previous studies have demonstrated that Catechol tetra hydroisoquinolines (CTIQs) are toxic to dopaminergic neurons. These toxins can induce mitochondrial dysfunction, which consequently contributes to the pathogenesis of PD. Unlike external neurotoxins, such as agrochemicals and MPTP, CTIQs can be synthesized in the brains of human based on the dopamine and the particular aldehyde. Besides, aggregated α-synuclein (α-syn), one of the hallmarks of PD, has been proved to be a key contributor in the development of PD and can be affected by many neurotoxins. Some studies have presented that CTIQs enhanced the aggregation of α-syn and increased the neurotoxin of α-syn, which might be the pathological mechanism of PD. Therefore, this chapter will reveal the role of CTIQs and α-syn and try to clarify the relationship between them.