Neuroinflammatory chemokine networks in transgenic models of Alzheimer's disease: A comparative multi-compartmental analysis.

Abstract

BackgroundAlzheimer's disease (AD) progression is critically modulated by neuroinflammatory cascades involving chemokine-mediated glial activation.ObjectiveThis study aimed to systematically compare compartment-specific chemokine signatures between two distinct AD mouse models (2×Tg-AD [APPswe/PS1dE9] and 3×Tg-AD [APPswe/PS1M146V/TauP301L]), hypothesizing that differential chemokine expression patterns would emerge in a model- and brain region-specific manner, correlating with glial activation profiles.ResultsUsing a Luminex liquid suspension chip assay, we quantified 22 chemokines in serum and brain tissues from transgenic and non-transgenic controls, complemented by Western blot analysis of microglial and astrocytic markers. Twenty-two chemokines were quantitatively analyzed with three key findings: First, serum analysis revealed elevated levels of (i) CCL11, CCL17, CCL24, CCL27, and CXCL12 in 3×Tg-AD versus non-Tg mice; (ii) CCL22 in 2×Tg-AD versus non-Tg mice; and (iii) CCL5, CCL11, CCL17, CCL24, CCL27, and CXCL12 in 3×Tg-AD versus 2×Tg-AD mice. Second, hippocampal changes showed upregulation of CCL3/CCL12 in 2×Tg-AD and CXCL16 in 3×Tg-AD mice, with cortical alterations demonstrating distinct CCL3/CCL12/CCL4 increases in 2×Tg-AD versus elevated CCL1/CXCL13 in 3×Tg-AD mice. Third, Western blot confirmed enhanced hippocampal microglial activation specifically in 3×Tg-AD mice. ConclusionOur findings establish model-specific chemokine signatures that differentially engage neuroinflammatory pathways, suggesting that 3×Tg-AD mice may better replicate human AD's complex chemokine-glia interactions. This compartmentalized profiling provides a framework for targeting chemokine networks in model-specific therapeutic development and biomarker discovery. Further studies are needed to determine whether elevated chemokine expression directly contributes to microglial activation.