A Novel Glucocerebrosidase Allosteric Activator Prevents MPTP-Induced Neurodegeneration in Mice

Mutations in the GBA1 gene, encoding lysosomal β-glucocerebrosidase (GCase), cause Gaucher disease (GD) and represent the most common genetic risk factor for Parkinson’s disease (PD). To target this pathway, therapeutic approaches for both GD and PD are actively being developed, focusing on two main drug classes: pharmacological chaperones (e.g., ambroxol) and allosteric GCase activators. Here, we characterize a novel allosteric GCase activator, N2, a derivative of the non-inhibitory chaperone NCGC607, and evaluate its therapeutic potential using computational, in vitro, and in vivo approaches. Molecular docking and molecular dynamics simulations indicated that N2 binds within the allosteric site of the mutant p.N370S GCase structure. In patient-derived cells (peripheral blood mononuclear cell-derived macrophages and induced pluripotent stem cell-derived dopaminergic neurons from GD and GBA1-PD patients), N2 enhanced GCase lysosomal translocation, modulated its enzymatic activity and protein level, and reduced substrate accumulation. Furthermore, we demonstrate for the first time that N2 exerts robust neuroprotective effects in an in vivo 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. Specifically, N2 treatment attenuated MPTP-induced hexosylsphingosine accumulation in the prefrontal cortex, and ameliorated both tyrosine hydroxylase-positive neuronal loss in the substantia nigra and dopamine depletion in the striatum. Our findings first demonstrated the neuroprotective properties of a GCase allosteric activator on an MPTP-induced mouse model of PD and supported the emerging perspectives of such compounds for the treatment of GCase-related disorders.