Paired plasma lipidomics and proteomics analysis in the conversion from mild cognitive impairment to Alzheimer's

Alicia Gómez-Pascual1, Talel Naccache2, Jin Xu3

  • 1Department of Information and Communications Engineering Faculty of Informatics, University of Murcia, Murcia, Spain; Steno Diabetes Center Copenhagen, Herlev, Denmark.

Abstract

Insights

Machine learning identified key molecules, including the metabolite oleamide, involved in mild cognitive impairment (MCI) progression to Alzheimer's disease (AD). This approach aids in understanding neuroinflammation and developing diagnostic tools for AD.

Area of Science:

  • Neuroscience
  • Biochemistry
  • Computational Biology

Background:

  • Alzheimer's disease (AD) is a progressive neurodegenerative disorder with no cure.
  • Mild cognitive impairment (MCI) is a precursor stage to AD, necessitating research into its progression mechanisms.
  • Understanding the molecular changes from MCI to AD is crucial for early detection and intervention.

Purpose of the Study:

  • To develop a machine learning model for identifying key metabolites and proteins associated with MCI progression to AD.
  • To analyze multimodal biomarker data for distinguishing between control, MCI, and AD states, and between stable MCI and MCI converters.
  • To uncover molecular pathways, particularly neuroinflammation, involved in MCI to AD transition.

Main Methods:

  • Utilized machine learning algorithms to analyze proteomic and metabolomic data from the European Medical Information Framework for Alzheimer's Disease Multimodal Biomarker Discovery Study.
  • Employed multiclass models to differentiate between controls, MCI, and AD, and binary models to predict MCI conversion.
  • Selected features validated by at least three out of four algorithms and confirmed in an independent cohort.

Main Results:

  • Metabolomic analysis identified nine key features, including oleamide, with high accuracy (0.726 mean balanced accuracy) in an independent cohort; oleamide was excreted by microglia.
  • Proteomic analysis yielded nine features with significant predictive power (0.720 mean balanced accuracy), though no single protein was consistently selected by all algorithms.
  • Models predicting MCI conversion identified 14 key features, including tTau, SNCA, JPH3, CFP, and PI15, with high performance (0.872 AUC).

Conclusions:

  • An omics integration approach successfully identified molecular signatures associated with MCI progression to AD.
  • The findings highlight the role of specific metabolites and proteins in neuronal and glial inflammation pathways.
  • This research provides a foundation for developing novel biomarkers and therapeutic strategies for Alzheimer's disease.