Age-related increase of VGF-expression in T lymphocytes

Aging (Albany NY). 2014 Jun;6(6):440-53. doi: 10.18632/aging.100656.

Abstract

VGF is a protein expressed by neurons and processed into several peptides. It plays a role in energy homeostasis and promotes growth and survival. Recently, VGF mRNA was detected in peripheral leukocytes. Since it is known that aging is associated with a decrease in the development and function of neuronal as well as immune cells, we addressed the question whether a peripheral expression of VGF by CD3+ T cells and CD56+ NK cells is correlated with age. Therefore, the frequency of VGF+CD3+ and VGF+CD56+ cells was determined in mentally healthy volunteers aged between 22 and 88. We found an age-dependent increase in the number of VGF+CD3+ T cells that correlated with HbA1c and the body mass index (BMI). VGF-expression by NK cells was age-independent. Blockade of VGF reduced proliferation and secretion of cytokines such as IL-2, IL-17A, IL-1β, IL-10 and TNF by CD3+ T cells and PBMCs. Rapamycin-mediated T cell blockade significantly reduced the frequency of VGF-expressing T cells. We conclude that VGF contributes to survival and function of peripheral T cells. The age-dependent increase in VGF-expression could serve as mechanism that counterregulates the decrease in functionality of T lymphocytes.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Flow Cytometry
  • Humans
  • Killer Cells, Natural / metabolism
  • Lymphocyte Subsets / metabolism
  • Male
  • Middle Aged
  • Nerve Growth Factors / immunology*
  • Nerve Growth Factors / metabolism*
  • T-Lymphocytes / metabolism*
  • Vascular Endothelial Growth Factor A / biosynthesis
  • Vascular Endothelial Growth Factor A / immunology
  • Young Adult

Substances

  • Nerve Growth Factors
  • VEGFA protein, human
  • VGF protein, human
  • Vascular Endothelial Growth Factor A