Omics-derived biological modules reflect metabolic brain changes in Alzheimer's disease

Alzheimers Dement. 2024 Oct;20(10):6709-6721. doi: 10.1002/alz.14095. Epub 2024 Aug 14.

Abstract

Introduction: Brain glucose hypometabolism, indexed by the fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) imaging, is a metabolic signature of Alzheimer's disease (AD). However, the underlying biological pathways involved in these metabolic changes remain elusive.

Methods: Here, we integrated [18F]FDG-PET images with blood and hippocampal transcriptomic data from cognitively unimpaired (CU, n = 445) and cognitively impaired (CI, n = 749) individuals using modular dimension reduction techniques and voxel-wise linear regression analysis.

Results: Our results showed that multiple transcriptomic modules are associated with brain [18F]FDG-PET metabolism, with the top hits being a protein serine/threonine kinase activity gene cluster (peak-t(223) = 4.86, P value < 0.001) and zinc-finger-related regulatory units (peak-t(223) = 3.90, P value < 0.001).

Discussion: By integrating transcriptomics with PET imaging data, we identified that serine/threonine kinase activity-associated genes and zinc-finger-related regulatory units are highly associated with brain metabolic changes in AD.

Highlights: We conducted an integrated analysis of system-based transcriptomics and fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) at the voxel level in Alzheimer's disease (AD). The biological process of serine/threonine kinase activity was the most associated with [18F]FDG-PET in the AD brain. Serine/threonine kinase activity alterations are associated with brain vulnerable regions in AD [18F]FDG-PET. Zinc-finger transcription factor targets were associated with AD brain [18F]FDG-PET metabolism.

Keywords: Alzheimer's disease; fluorodeoxyglucose positron emission tomography; systems biology; transcriptomics.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease* / diagnostic imaging
  • Alzheimer Disease* / genetics
  • Alzheimer Disease* / metabolism
  • Brain* / diagnostic imaging
  • Brain* / metabolism
  • Cognitive Dysfunction / diagnostic imaging
  • Cognitive Dysfunction / genetics
  • Cognitive Dysfunction / metabolism
  • Female
  • Fluorodeoxyglucose F18* / metabolism
  • Hippocampus / diagnostic imaging
  • Hippocampus / metabolism
  • Humans
  • Male
  • Positron-Emission Tomography*
  • Transcriptome

Substances

  • Fluorodeoxyglucose F18