CSF N-acylethanolamine acid amidase level and Parkinson's disease risk: A mendelian randomization study

Youjie Zeng; Ren Guo; Si Cao; Chunxia Liu; Heng Yang

doi:10.1016/j.parkreldis.2024.106953

CSF N-acylethanolamine acid amidase level and Parkinson's disease risk: A mendelian randomization study

Parkinsonism Relat Disord. 2024 Apr 2:123:106953. doi: 10.1016/j.parkreldis.2024.106953. Online ahead of print.

Authors

Youjie Zeng¹, Ren Guo², Si Cao³, Chunxia Liu¹, Heng Yang⁴

Affiliations

¹ Department of Anesthesiology, Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.
² Department of Pharmacy, Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.
³ Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-XIANGYA, Changsha, 410205, Hunan, China.
⁴ Department of Neurology, Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China. Electronic address: johnnelyang@hotmail.com.

PMID: 38579440
DOI: 10.1016/j.parkreldis.2024.106953

Abstract

Background: Neuroinflammation is involved in the progression of Parkinson's disease (PD), and N-acylethanolamine acid amidase (NAAA) is involved in regulating inflammation by hydrolyzing bioactive lipid mediators called N-acylethanolamines (NAEs). However, the causal relationship between cerebrospinal fluid (CSF) NAAA protein levels and the risk of PD remains unclear. This study aimed to explore the causal effect of CSF NAAA levels on PD risk through Mendelian randomization (MR) analysis.

Method: Genome-wide association study (GWAS) summary statistics for CSF NAAA protein quantitative trait loci (pQTL) and GWAS summary statistics for PD were obtained from publicly available databases. Inverse-variance weighted (IVW) was the main causal estimation method for MR analysis. In addition, the maximum likelihood, MR Egger regression, and weighted median were used to supplement the IVW results. Finally, various sensitivity tests were performed to verify the reliability of the MR findings.

Results: In the initial MR analysis, the IVW showed that CSF NAAA protein levels significantly increased PD risk (odds ratio [OR] = 1.17, 95% confidence interval [CI]: 1.01-1.35, P = 0.031). This finding was further validated in a replicate MR analysis (OR = 1.20, 95% CI: 1.02-1.41, P = 0.027). Sensitivity analysis showed that MR results were stable and not affected by heterogeneity and horizontal pleiotropy.

Conclusion: The present MR study supports a causal relationship between elevated CSF NAAA protein levels and increased PD risk.

Keywords: Causal relationship; Incidence risk; Mendelian randomization; N-acylethanolamine acid amidase; Parkinson's disease; pQTL.