Serum levels of lipocalin-2 in patients with Parkinson’s disease

Background Parkinson’s disease (PD) is the second most common neurodegenerative disease. Evidence has shown that lipocalin-2 (LCN2) is involved in the pathological process of PD. We aimed to explore whether serum levels of LCN2 could be a biomarker of PD. Methods We recruited consecutive PD patients and healthy controls (HC) in our hospital from June 2020 to July 2020. Serum LCN2 levels were detected using the LCN2 enzyme-linked immunosorbent assay (ELISA) kit. The motor section of the Unified Parkinson’s Disease Rating Scale (UPDRS III) and the Hoehn and Yahr Staging Scale (H&Y) were assessed on admission to evaluate disease severity in patients with PD. Cognitive status was measured by the Montreal Cognitive Assessment (MoCA). Results We finally recruited 75 patients, including 40 PD patients and 35 HC. Serum LCN2 levels were not significantly increased in PD patients compared with HC (4.9 [− 0.7 to 18.6] vs 1.9 [− 1.5 to 16.9] ng/mL, P = 0.33). Besides, there was no significant difference in LCN2 levels between patients at early and advanced stage of PD ( P = 0.75), as well as between cognitively impaired PD patients, PD patients with normal cognition, and HC ( P = 0.30). Moreover, LCN2 had no correlation with disease duration ( r = − 0.1, P = 0.37), UPDRS III score ( r = 0.07, P = 0.65), and MoCA score ( r = 0.221, P = 0.17). Conclusions Overall, our study suggests that serum LCN2 levels may not be a biomarker for PD.