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Updated: Sep 17, 2025
08:42
Skeletal Phenotype Analysis of a Conditional Stat3 Deletion Mouse Model
Published on: July 3, 2020
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Sirtuin-3 promotes osteoclast maturation and bone loss by regulating mitochondrial ROS production during ionizing
Gareeballah Osman Adam1,2, Kimberly K Richardson1,2, Ankita Chalke1,2
1Center for Musculoskeletal Disease Research, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
JBMR Plus
|June 30, 2025
Summary
Sirtuin-3 (SIRT3) deletion protects against ionizing radiation-induced bone loss by impairing osteoclast function and reducing mitochondrial reactive oxygen species (ROS) production. This highlights SIRT3
Area of Science:
- Mitochondrial biology
- Bone cell biology
- Radiation biology
Background:
- Ionizing radiation (IR) causes mitochondrial damage in bone cells, leading to bone loss.
- Sirtuin-3 (SIRT3) regulates mitochondrial function and bone resorption, but its role in IR-induced bone disorders is unknown.
Purpose of the Study:
- To investigate the role of SIRT3 in IR-induced bone disorders.
- To elucidate the mechanisms by which SIRT3 influences osteoclast activity and mitochondrial function under IR exposure.
Main Methods:
- Utilized Sirt3 knockout mice to assess bone mass and osteoclast function after IR exposure.
- Analyzed mitochondrial activity, reactive oxygen species (ROS) production, and superoxide dismutase 2 (SOD2) acetylation in osteoclasts.
- Employed Mito-TEMPO to inhibit mitochondrial ROS.
Main Results:
- Sirt3 deletion significantly attenuated IR-induced bone loss by impairing osteoclast maturation and function.
- IR exposure increased mitochondrial activity and ROS production in osteoclasts, effects abrogated by Sirt3 deletion.
- SIRT3-mediated deacetylation of SOD2 enhanced osteoclast formation and mitochondrial ROS, mimicking IR exposure effects.
Conclusions:
- SIRT3 is crucial in mediating IR-induced bone resorption through mitochondrial deacetylation in osteoclasts.
- Targeting SIRT3 and mitochondrial ROS may offer therapeutic strategies for IR-induced bone disorders.
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