LPIN1 and Parkinson disease: The plasmic concentration of LPIN1 in patients with PD (105.7 ng/mL [range 56.98 to 161.3 ng/mL]) was significantly lower than that in HC (121.0 ng/mL [range 87.03 to 773.4 ng/mL]) (p < 0.0001) (Fig. 9A).