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Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
14:22

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development

Published on: April 15, 2013

"Bound" to work: the free hormone hypothesis revisited

John S Adams1

  • 1Burns and Allen Research Institute, Cedars-Sinai Medical Center, David Geffen School of Medicine at UCLA, University of California, Los angeles, CA 90048, USA.

Cell
|September 7, 2005
PubMed

Insights

Animals lacking megalin, a receptor involved in cellular uptake, exhibit resistance to sex steroid hormones. This suggests megalin plays a crucial role in mediating the effects of these vital hormones.

Area of Science:

  • Endocrinology
  • Cell Biology
  • Molecular Biology

Background:

  • Megalin is a cell surface receptor belonging to the low-density lipoprotein receptor-related protein (LRP) family.
  • LRP family members function as endocytic receptors for diverse extracellular ligands.
  • This study investigates the physiological role of megalin in relation to sex steroid hormone action.

Discussion:

  • The absence of megalin leads to insensitivity to sex steroid hormones in animal models.
  • This finding implicates megalin in the cellular uptake or signaling pathways of sex steroids.
  • The study highlights an endocytic mechanism for sex steroid hormone transport into mammalian cells.

Key Insights:

  • Megalin-deficient animals display impaired responses to sex steroid hormones.
  • This suggests a critical role for megalin in mediating sex steroid hormone bioavailability or action.
  • The research uncovers a novel endocytic pathway for sex steroid uptake.

Outlook:

  • Further research can elucidate the specific sex steroid ligands recognized by megalin.
  • Understanding this pathway may offer new therapeutic targets for hormone-related disorders.
  • Investigating megalin's function could reveal broader implications for steroid hormone signaling.

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