LAX1 as a core biomarker in Alzheimer’s disease and periodontitis via the STAT signaling pathway
摘要
The relationship between Alzheimer’s disease (AD) and chronic periodontitis (PD) rarely share the medical spotlight, yet epidemiological mirroring hints at a common inflammatory root.
MethodsMining four GEO (Gene Expression Omnibus) cohorts (211 AD + 27 controls; 24 PD + 23 controls), batch-corrected and validated by principal component analysis (PCA)/t-distributed stochastic neighbour embedding (t-SNE)/uniform manifold approximation and projection (UMAP), we identified 61 shared differentially expressed genes (DEGs) with lymphocyte transmembrane adaptor 1 (LAX1) ranked first in weighted gene co-expression network analysis (WGCNA), maximum clique centrality (MCC), Degree, edge percolated component (EPC) and Stress algorithms, tightly co-expressed with colony-stimulating factor 3 receptor (CSF3R) and signal transducer and activator of transcription 1/3 (STAT1/3). Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene set enrichment analysis (GSEA) uniquely highlighted the “LAX1/CSF3R/STAT” triad in apoptosis and JAK-STAT cascades. CIBERSORT de-convolution showed LAX1 covaried with plasma-cell, mast-cell and M0-macrophage infiltration.
ResultsPlasma from 42 AD and 38 stage-III/IV PD patients showed elevated soluble LAX1 (sLAX1) correlating with Mini-Mental State Examination (MMSE) decline (r =—0.67) and clinical attachment loss (r = 0.71), outperforming Aβ42 and receptor activator of nuclear factor-κB ligand (RANKL) in receiver operating characteristic (ROC) analyses (area under the curve [AUC] = 0.91). We hypothesised that LAX1 orchestrates the dialogue via the STAT axis. In human periodontal-ligament fibroblasts and 5 × FAD glia exposed to Porphyromonas gingivalis LPS or amyloid-β42 (Aβ42), LAX1 overexpression (pCMV6-LAX1) amplified STAT1/3 phosphorylation, elevated interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) by 2.3—3.1-fold and escalated p53, cleaved caspase-3 and FAS, whereas LAX1 small interfering RNA (siRNA) abolished these effects. In other words, targeting of the LAX1 validated that the inflammatory/apoptotic signature scales with LAX1 abundance.
ConclusionLAX1 gates STAT-dependent neuroinflammation and periodontal destruction, offering a druggable checkpoint and blood-based biomarker for these convergent chronic diseases.