Furthermore, a recent study using induced pluripotent stem cell-derived microglia from iPD patients showed an upregulation of IL-1β and NLRP3, both at the mRNA and protein levels, when compared to healthy controls [161], which confirm a study finding a high expression of NLRP3 in activated microglia as well as elevated apoptosis-associated speck-like protein containing a caspase recruitment domain 1 (ASC1) and caspase-1 in the SN of post-mortem PD brains [122]. This evidence concerns the gene CASP1 and Parkinson disease.