Moreover, while CFA significantly increased Hspb1 levels in Nrf2-deficient (Nrf2-/-) mice compared to untreated MPTP groups, the extent of this increase was markedly less than that observed in WT mice (Figure 3J), indicating that Nrf2 activation plays a critical role in Hspb1 upregulation in PD. Here, HSPB1 is linked to Parkinson disease.