Abstract
INTRODUCTION
Growing evidence indicates that fine particulate matter (PM2.5) is a risk factor for Alzheimer’s disease (AD), but the underlying mechanisms have been insufficiently investigated. We hypothesized differential DNA methylation (DNAm) in brain tissue as a potential mediator of this association.
METHODS
We assessed genome-wide DNAm (Illumina EPIC BeadChips) in prefrontal cortex tissue and three AD-related neuropathological markers (Braak stage, CERAD, ABC score) for 159 donors, and estimated donors’ residential traffic-related PM2.5 exposure 1, 3, and 5 years prior to death. We used a combination of the Meet-in-the-Middle approach, high-dimensional mediation analysis, and causal mediation analysis to identify potential mediating CpGs.
RESULTS
PM2.5 was significantly associated with differential DNAm at cg25433380 and cg10495669. Twenty-four CpG sites were identified as mediators of the association between PM2.5 exposure and neuropathology markers, several located in genes related to neuroinflammation.
DISCUSSION
Our findings suggest differential DNAm related to neuroinflammation mediates the association between traffic-related PM2.5 and AD.
Highlights
First study to evaluate the potential mediation effect of DNA methylation for the association between PM2.5 exposure and neuropathological changes of Alzheimer’s disease.
Study was based on brain tissues rarely investigated in previous air pollution research.
Cg10495669, assigned to RBCK1 gene playing a role in inflammation, was associated consistently with 1-year, 3-year, and 5-year traffic-related PM2.5 exposures prior to death.
Meet-in-the-middle approach and high-dimensional mediation analysis were used simultaneously to increase the potential of identifying the differentially methylated CpGs.
Differential DNAm related to neuroinflammation was found to mediate the association between traffic-related PM2.5 and Alzheimer’s disease.
If you do not see content above, kindly GO TO SOURCE.
Not all publishers encode content in a way that enables republishing at Neuro.vip.
This post is Copyright: Zhenjiang Li,
Donghai Liang,
Stefanie Ebelt,
Marla Gearing,
Michael S. Kobor,
Chaini Konwar,
Julie L. Maclsaac,
Kristy Dever,
Aliza P. Wingo,
Allan I. Levey,
James J. Lah,
Thomas S. Wingo,
Anke Hüls | February 12, 2024