Neutrophil-to-lymphocyte ratio and lymphocyte count reflect alterations in central neurodegeneration-associated proteins and clinical severity in Parkinson Disease patients

• DOI: 10.1016/j.parkreldis.2023.105480
• Publication Date: 2023-06-04T05:25:16Z
• Authors: Piergiorgio Grillo; Giulia Maria Sanc...; Roberta Bovenzi; Henri Zenuni; Jacopo Bissacco; Davide Mascioli; Clara Simonetta; Paolo Forti; Giulia Rebecca De...; Massimo Pieri; Valerio Chiurchiù; Alessandro Stefani; Nicola Biagio Mer...; Tommaso Schirinzi
• Keywords: Blood cell count; Settore BIOS-09/A - Biochimica clinica e biologia molecolare clinica; Amyloid beta-Peptides; Neutrophils; 610; Parkinson Disease; tau Proteins; 3. Good health; Lymphocytes count; Alpha-synuclein; Cerebrospinal fluid; alpha-Synuclein; Humans; Lymphocytes; Lymphocyte Count; Amyloid-beta; Neutrophil-to-lymphocyte ratio; Biomarkers

Peripheral inflammation has been recently associated to Parkinson disease (PD). However, how the peripheral inflammatory immune response could affect the clinical-pathological features of the disease is not fully understood. In this study, we assessed the peripheral immune profile of a well-characterized PD cohort, examining several correlations with CSF biomarkers of neurodegeneration and the main clinical parameters, aimed at better elucidating the complex dynamics of the brain-periphery interactions in PD.The leukocyte populations counts (neutrophils, lymphocytes, monocytes, eosinophils, and basophils) and the neutrophil-to-lymphocyte ratio (NLR) were collected and compared in 61 PD patients and 60 sex/age matched controls (CTRLs). Immune parameters were correlated with CSF levels of total α-synuclein, amyloid-β-42, total and phosphorylated-tau and main motor and non-motor scores.PD patients had lower lymphocyte and higher NLR counts compared to CTRLs. In PD patients, the lymphocyte count directly correlated with CSF α-synuclein levels, whereas NLR displayed an inverse correlation with the CSF amyloid-β42 levels. The lymphocyte count also negatively correlated with HY stage, while NLR positively with the disease duration.This study provided in vivo evidence that, in PD, changes in leukocytes in the periphery, assessed as relative lymphopenia and NLR increase, reflect in central neurodegeneration-associated proteins modifications, especially in α-synuclein and amyloid-β pathways, and greater clinical burden.