CST3 and Parkinson disease: Multiple cohort studies have confirmed that inflammatory markers such as plasma C-reactive protein (CRP) (11) and the specific proteins of the central nervous system (S100) protein family (12), as well as renal function parameters including creatinine (Cr) (13), cystatin C (Cys C) (14), and estimated glomerular filtration rate (eGFR), are associated with PD.