BjPro-7a, A Proline-Rich Peptide from Bothrops jararaca Venom, Reverses MPP⁺-Induced Locomotor Deficits and Rescues...

Parkinson's disease (PD) and related Parkinsonian conditions involve progressive disruption of mitochondrial homeostasis, redox balance, synaptic function, and proteostasis. Available therapies remain predominantly symptomatic, motivating the search for multitarget compounds acting across stress-sensitive pathways. BjPro-7a (pEDGPIPP), a proline-rich oligopeptide from Bothrops jararaca venom, exerts cytoprotective effects under oxidative stress, but its activity in an in vivo Parkinsonian-like model is unknown. Here we investigated whether BjPro-7a attenuates the behavioral and proteomic disturbances induced by 1-methyl-4-phenylpyridinium (MPP⁺) in zebrafish larvae. Larvae were exposed to 500 µM MPP⁺ and post-treated with 10 µM BjPro-7a, followed by assessment of basal locomotion, light/dark-evoked behavior, and label-free proteomic profiling. BjPro-7a markedly reversed the MPP⁺-induced hypolocomotor phenotype by increasing the total distance traveled, improving bout-related parameters, reducing inter-episode intervals, and restoring visually evoked responsiveness. Proteomic analysis revealed broad rescue-associated remodeling, more pronounced among proteins suppressed by MPP⁺ than among those elevated by intoxication. Functional enrichment and protein-protein interaction analyses indicated coordinated modulation of vesicle trafficking and synaptic organization, mitochondrial and bioenergetic function, redox homeostasis, and protein quality control. Representative rescue-associated proteins included VAMP2 and SNAP25A (synaptic), SDHA and UQCRFS1 (mitochondrial), G6PD and PRDX3 (redox), and PSMC5 and STIP1 (proteostasis). Together, these findings show that BjPro-7a attenuates MPP⁺-induced dysfunction and promotes systems-level proteomic remodeling consistent with rescue in zebrafish larvae. These data support BjPro-7a as a promising candidate for future therapeutic studies in Parkinsonian-like neurotoxicity.