CNP and Parkinson disease: To model PD we used a parkinsonian mouse that expresses A53T mutant human alpha-synuclein (a-Syn) in neurons [19], referred to here as A53T transgenic (Tg) mice and an MSA mouse model that expresses human aSyn in oligodendrocytes under the 2, ′ 3′-cyclic nucleotide 3′-phosphodiesterase (CNP) promoter [20], referred to here as CNP-aSyn transgenic (Tg) mice.