In vitro and in vivo neuroprotective effect of novel mPGES-1 inhibitor in animal model of Parkinson's disease

mPGES-1 is found to be up-regulated in the dopaminergic neurons of the substantia nigra pars compacta (SNpc) of postmortem brain tissue from Parkinson's disease (PD) patients and neurotoxin 6-hydroxydopamine (6-OHDA)-induced PD mice. Since the genetic deletion of mPGES-1 abolished 6-OHDA-induced PGE₂ production and 6-OHDA-induced dopaminergic neurodegeneration in vitro and in vivo models, mPGES-1 enzyme has the potential to be an important target for PD therapy. In the present work, we investigated whether a small organic molecule as mPGES-1 inhibitor could exhibit the neuroprotective effects against 6-OHDA-induced neurotoxicity in in vitro and in vivo models. For this research goal, a new series of arylsulfonyl hydrazide derivatives was prepared and investigated whether these compounds may protect neurons against 6-OHDA-induced neurotoxicity in both in vitro and in vivo studies. Among them, compound 7s (MPO-0144) as a mPGES-1 inhibitor (PGE₂ IC₅₀ = 41.77 nM; mPGES-1 IC₅₀ = 1.16 nM) exhibited a potent neuroprotection (ED₅₀ = 3.0 nM) against 6-OHDA-induced in PC12 cells without its own neurotoxicity (IC₅₀ = >10 μM). In a 6-OHDA-induced mouse model of PD, administration of compound 7s (1 mg/kg/day, for 7 days, i.p.) ameliorated motor impairments and dopaminergic neuronal damage. These significant biological effects of compound 7s provided the first pharmacological evidence that mPGES-1 inhibitor could be a promising therapeutic agent for PD patients.