MCP-1 and eotaxin-1 selectively and negatively associate with memory in MCI and Alzheimer's disease dementia phenotypes

Area of Science:

• Neuroscience
• Immunology
• Genetics

Background:

• Monocyte chemoattractant protein-1 (MCP-1) and eotaxin-1, encoded on chromosome 17, are known to impair hippocampal neurogenesis in mice.
• Investigating the specific association of these chemokines with memory deficits in human cognitive impairment is crucial.

Purpose of the Study:

• To determine if MCP-1 and eotaxin-1 selectively correlate with memory impairment in individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD) dementia.
• To explore the relationship between these chemokines and brain structure in affected individuals.

Main Methods:

• Assayed MCP-1 and eotaxin-1 levels in control, MCI, and AD dementia patients (n=171).
• Utilized magnetic resonance imaging (MRI) on a subset (n=55) to assess medial temporal lobe volumes.
• Created composite cognitive scores and analyzed associations with chemokine levels and brain imaging data.

Main Results:

• An interaction between MCP-1 and eotaxin-1 was observed, where elevated levels of both correlated with memory impairment.
• These associations remained significant even after accounting for APOE genotype and other chemokines.
• Elevated MCP-1 and eotaxin-1 predicted reduced left medial temporal lobe volume but did not impact other cognitive domains.

Conclusions:

• MCP-1 and eotaxin-1 may play a selective role in memory dysfunction associated with MCI and AD dementia.
• These findings highlight potential therapeutic targets for memory deficits in neurodegenerative diseases.