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Published on: March 15, 2018
TRAIL is involved in human osteoclast apoptosis
Giacomina Brunetti1, Angela Oranger, Giorgio Mori
1Department of Human Anatomy and Histology, University of Bari, Medical School, Bari, Italy.
Annals of the New York Academy of Sciences
|June 23, 2007
Summary
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in human osteoclasts (OCs), a key factor in bone remodeling. This cell death is mediated by the death receptor DR5, offering potential therapeutic targets for bone diseases.
Area of Science:
- Bone Biology and Osteoclast Function
- Cell Death and Apoptosis Signaling
Background:
- Osteoclast (OC) apoptosis is crucial for maintaining bone homeostasis and remodeling.
- Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is known to induce apoptosis in various cell types.
- Limited information exists regarding TRAIL's impact on bone cells, particularly mature human OCs.
Purpose of the Study:
- To investigate the role of TRAIL in inducing apoptosis of human mature osteoclasts.
- To identify the specific molecular mechanisms and receptors involved in TRAIL-mediated OC apoptosis.
Main Methods:
- Treatment of mature human OCs with TRAIL.
- Assessment of cell viability and nuclear integrity.
- Analysis of actin microfilament organization.
- Evaluation of death receptor 5 (DR5) expression following TRAIL treatment.
Main Results:
- TRAIL treatment significantly reduced osteoclast cell viability.
- TRAIL induced loss of nuclear integrity and disrupted the actin cytoskeleton in OCs.
- TRAIL upregulated the expression of the death receptor DR5 on OCs.
- DR5 appears to mediate TRAIL-induced apoptosis in osteoclasts.
Conclusions:
- TRAIL effectively induces apoptosis in human mature osteoclasts.
- The death receptor DR5 is implicated as the mediator of TRAIL's apoptotic effect on OCs.
- These findings highlight TRAIL/DR5 signaling as a potential target for modulating bone remodeling.
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