Related Experiment Video

Updated: Jul 20, 2026

Peptides from Phage Display Library Modulate Gene Expression in Mesenchymal Cells and Potentiate Osteogenesis in Unicortical Bone Defects
07:53

Peptides from Phage Display Library Modulate Gene Expression in Mesenchymal Cells and Potentiate Osteogenesis in Unicortical Bone Defects

Published on: December 10, 2010

Stay tuned to PXR: an orphan actor that may not be D-structive only to bone

Michael F Holick1

  • 1Vitamin D, Skin, and Bone Research Laboratory, Section of Endocrinology, Diabetes, and Nutrition, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts 02118, USA. mfholick@bu.edu

The Journal of Clinical Investigation
|January 5, 2005
PubMed

Insights

Pregnane X receptor (PXR) can cause vitamin D deficiency by affecting vitamin D metabolism. Identifying and treating PXR-induced vitamin D deficiency is crucial for mitigating bone disease risks.

Area of Science:

  • Endocrinology
  • Pharmacology
  • Bone Biology

Background:

  • Pregnane X receptor (PXR) is a key regulator of xenobiotic and drug metabolism.
  • Vitamin D is essential for calcium homeostasis and bone health.
  • Disruptions in vitamin D metabolism can lead to bone disease.

Purpose of the Study:

  • To investigate the role of PXR in vitamin D metabolism.
  • To determine if PXR activation leads to vitamin D deficiency and bone disease.
  • To explore potential therapeutic strategies for PXR-induced vitamin D deficiency.

Main Methods:

  • Studies involving PXR activation and its effects on vitamin D catabolism.
  • Analysis of vitamin D levels and bone health markers in relevant models.
  • Investigation of the cross-talk between PXR and vitamin D-responsive genes.

Main Results:

  • PXR activation was shown to induce vitamin D deficiency.
  • PXR was found to cross-talk with genes responsible for vitamin D catabolism.
  • This interaction leads to increased breakdown of 25-hydroxy-vitamin D and 1,25-dihydroxyvitamin D.
  • Vitamin D deficiency induced by PXR is linked to bone disease.

Conclusions:

  • PXR plays a significant role in regulating vitamin D levels.
  • PXR-mediated vitamin D deficiency has important health implications, particularly for bone health.
  • Targeting PXR or managing vitamin D deficiency can mitigate associated bone diseases.

More Related Videos

Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts07:56

Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts

Published on: January 29, 2018

Establishment of Patient-Derived Xenograft Mouse Model with Human Osteosarcoma Tissues02:35

Establishment of Patient-Derived Xenograft Mouse Model with Human Osteosarcoma Tissues

Published on: March 22, 2024

Related Concept Videos

Bone Structure01:55

Bone Structure

Within the skeletal system, the structure of a bone, or osseous tissue, can be exemplified in a long bone, like the femur, where there are two types of osseous tissue: cortical and cancellous.
Bone Remodeling01:40

Bone Remodeling

Bone remodeling is a continuous and balanced process of bone resorption by osteoclasts and bone formation by osteoblasts. In adults, it helps maintain bone mass and calcium homeostasis. While mechanical stress can stimulate turnover as part of the normal maintenance and reparative process, several hormones also regulate bone remodeling.
The Bone Matrix01:18

The Bone Matrix

Bone contains a relatively small number of cells entrenched in a matrix of collagen fibers that provide an adherent surface for inorganic salt crystals. Both components of the matrix, organic and inorganic, contribute to the unusual properties of bone. Without collagen, bones would be brittle and shatter easily. Without mineral crystals, bones would flex and provide little support. This can be observed by an experiment: when the minerals of a bone are dissolved by soaking the bone in acid or...
Bone Remodeling and Repair01:31

Bone Remodeling and Repair

Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during bone...
Spongy Bone01:09

Spongy Bone

All bones comprise an outer layer of compact bone, and an interior made up of spongy bone tissue, also called cancellous or trabecular bone. In long bones, spongy bone tissue is mainly found in the interior of the epiphyses (broad ends of the bone).
Spongy bone is more porous, and less dense compared to compact bone. It is composed of concentric lamellae that are arranged irregularly to form the trabecular network. In some bones, the spaces between trabeculae contain red marrow, where...
Indeterminate Structure01:18

Indeterminate Structure

Indeterminate structures refer to structures where internal forces and reactions cannot be determined using only the equations of static equilibrium.  Indeterminate structures have more unknown forces and reaction forces than equations of static equilibrium that can be used to determine them. Indeterminate structures are often used in engineering to create complex, efficient, and aesthetically pleasing structures. There are various types of indeterminate structures used in engineering and some...