An established Drosophila PD model resulting from transgenic neuronal expression of the A53T mutant human α-synuclein protein 25 was used in these studies. We monitored locomotive functions in control flies (expressing LacZ) mutant flies using a negative geotaxic behavior assay (climbing assay) 26. Shown are climbing performance (expressed as percentage of flies that successfully performed the climbing test) of adult flies at the ages of 2, 10 and 20 DAE. Within each age group, bar graphs represent mean (±SEM) of control flies, vehicle (DMSO) treated A53T mutant flies, or A53T mutant flies treated with 3-HBA, 3-HPPA, or 3,4-diHBA (1 μM); n=10 flies per control, vehicle-treated or phenolic-acid treated group. Significance level was established by one-way ANOVA (P ≤ 0.0001); *** Bonferroni post-hoc test P ≤ 0.0001.