S100B and Parkinson disease: Furthermore, we previously reported that zonisamide and levetiracetam enhanced astroglial xCT expression and/or astroglial proliferation, increased GSH, and protected dopaminergic neurodegeneration in PD model [15,16], and that 5-HT1A receptor agonist 8-OH DPAT promoted Nrf2 activation, S100β, and MT secretion in striatal astrocytes to protect DA neurons in culture and in an animal model of PD [17].