In vitro proinflammatory gene expression predicts in vivo telomere shortening: A preliminary study

Area of Science:

• Immunology
• Cellular Biology
• Stress Research

Background:

• Chronic psychological stress, particularly from caregiving, increases disease risk.
• Chronic inflammation is a proposed mechanism linking stress to disease.
• The impact of caregiving stress on cellular aging via inflammation and telomere length in healthy humans is not well understood.

Purpose of the Study:

• To investigate the association between caregiving stress and inflammatory responses in peripheral blood mononuclear cells (PBMCs).
• To examine the relationship between inflammation and telomere length in healthy mothers of children with autism compared to controls.
• To determine if increased proinflammatory gene expression predicts future telomere shortening.

Main Methods:

• Compared PBMCs from mothers of children with autism (caregivers) and mothers of neurotypical children (controls).
• Stimulated PBMCs in vitro with phytohaemagglutinin (PHA) and measured immune gene expression.
• Assessed telomere length in PBMCs at baseline and 15 months later.

Main Results:

• Caregivers exhibited elevated RNA levels of key inflammatory regulators (NF-κB, IL-1β, IL-6, IL-8) and related molecules (COX-2) after PHA stimulation compared to controls.
• Gene expression suggested increased T helper cell differentiation (Treg and Th17) in caregivers.
• Higher expression of proinflammatory genes correlated with shorter telomere length in PBMCs collected 15 months later, irrespective of baseline telomere length.

Conclusions:

• Chronic stress in caregivers is associated with an exaggerated inflammatory response in immune cells.
• This heightened inflammatory response predicts future telomere shortening, indicating accelerated cellular aging.
• This is the first human study demonstrating that increased proinflammatory gene expression predicts subsequent telomere attrition.