Similar therapeutic benefits were obtained using analogs of rapamycin, such as CCI-779, which was shown to reduce mHTT aggregates, leading to improved motor behaviors in HD transgenic mice.215 In contrast, rapamycin worsened autophagic functions and neuron degeneration in a SOD1(G93A) transgenic mouse model of ALS212 and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxin models of PD,216 suggesting that autophagic induction may exert adverse effects on certain neurodegenerative conditions. Here, SOD1 is linked to Huntington disease.