Estrogen prevents age-dependent beige adipogenesis failure through NAMPT-controlled ER stress pathway

Insights

Estrogen (E2) treatment counteracts age-related decline in beige adipocyte formation in mice. This process involves nicotinamide phosphoribosyltranferase (NAMPT) signaling, mitigating ER stress and improving metabolic health.

Area of Science:

  • Metabolic disease research
  • Endocrinology
  • Cellular biology

Background:

  • Thermogenic beige adipocytes are crucial for metabolic health but decline with age.
  • Age-related decline impairs energy expenditure and glucose homeostasis.
  • Estrogen (E2) levels decrease with aging, potentially contributing to this decline.

Approach:

  • Investigated the effect of estrogen (E2) administration on aged mice.
  • Examined the role of nicotinamide phosphoribosyltranferase (NAMPT) in E2-mediated beige adipogenesis.
  • Assessed the impact on energy expenditure, glucose tolerance, and endoplasmic reticulum (ER) stress.

Key Points:

  • Estrogen (E2) treatment restored cold-induced beige adipocyte formation in aged mice.
  • E2 treatment improved energy expenditure and glucose tolerance.
  • Nicotinamide phosphoribosyltranferase (NAMPT) is essential for E2-induced beige adipocyte formation and ER stress suppression.

Conclusions:

  • Estrogen (E2) and NAMPT signaling counteract age-related beige adipocyte dysfunction.
  • Targeting NAMPT signaling can restore beige adipocyte formation by increasing progenitor cells.
  • E2-NAMPT controlled ER stress is a key regulator of age-dependent beige adipocyte impairment.

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