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Updated: Jul 13, 2026
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
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
Summary
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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