Effects Of Pesticides Commonly Used In China On The Proteasome And Mitochondria

Parkinson's disease (PD), the second most commom neurodegenerative disorders, affects greater than 1% of the China's population over the age of 65. Epidemiological study has identified rural living, well water, herbicide use and exposure to pesticides, as factors that may be linked to PD. Pesticides exposure increases the risks of Parkinsonisom by inhibiting the proteasome activity, causing mitochondial dysfunction or interacting with genetic factors.Chapter 1 Effects of Pesticides Commonly Used in China on the Proteasome and Mitochondria.Objective:To analyze the effect of 11 pesticides widely used in China on proteasome acticity and mitochondrial morphology.Methods:A stable cell line overexpressing GFP-CL1 in SH-SY5Y was established as a cellular model to test proteasome activity. CL1 encoding a fragment of amino acides (ACKNWFSSLSHFVIHL) was fused to GFP at its C-terminal, and can be ubiquitinated and degraded by proteasome. GFP-CL1 was continuously degraded and kept at very low levels under normal condition. Compromised proteasome function reduces the clearance capacity by UPS and increase steady-state GFP-CL1 levels. The expression of GFP-CL1 was detected by immunoblotting after pesticides exposure. Also, we observed the effect of pesticides on the morphology of motichondria in HeLa cells using immunofluorescence staining.Results:Nine pesticides, including paraquat, potenone, chlorpyrifos, pendimethalin,λ-cyhalothrin, cypermethrin, endosulfan, fenpyroximate, and tebufenpyrad, were found to inhibit proteasome activity to varying degrees. Also, common-used pesticides lead to mitochondrial morphological changes, different in degrees and kinds.Chapter 2 Cellular Models Stably Expressing PD-related Genes Were Established.Objective:To established cell lines stably expressing PD-related genes and their pathological mutants.Methods:We established cell lines stably expressing PD-related genes and their pathological mutants, including the Parkin wild-type and T240R mutant; PINK1 wild-type and G309D mutant; LRRK2 wild type and DJ-1 wild type. Also, we established the stable cell line overexpressing LC3 that can reflect the level of autophagy in SH-SY5Y.Results:Cellular models stably expressing PD-related genes were established.Conclusion:These celluler models stably expressing PD-related genes provide a basis for further study on gene-environment interaction in PD.