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Rapamycin reduces severity of senile osteoporosis by activating osteocyte autophagy

D Luo1, H Ren2, T Li1

  • 1Department of Orthopaedic Surgery, Orthopaedic Center of People's Liberation Army, The Affiliated Southeast Hospital of Xiamen University, Zhangzhou, 363000, China.

Osteoporosis International : a Journal Established As Result of Cooperation Between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA
|September 24, 2015
PubMed
Abstract

Insights

Rapamycin treatment in old male rats improved bone density and microstructure by activating osteocyte autophagy. This intervention reduced bone loss and osteocyte apoptosis, suggesting a potential therapy for senile osteoporosis.

Area of Science:

  • Bone Biology
  • Cellular Aging
  • Pharmacology

Background:

  • Osteocytes orchestrate bone remodeling; their declining autophagy contributes to senile osteoporosis.
  • Autophagy is crucial for osteocyte viability, and its age-related failure is linked to osteoporosis.

Purpose of the Study:

  • To investigate the protective effects of rapamycin, an autophagy activator, on senile osteoporosis.
  • To determine if rapamycin induces osteocyte autophagy and mitigates age-related bone deterioration.

Main Methods:

  • Old male rats received rapamycin or vehicle control for 12 weeks.
  • Bone mineral density, microstructure, mineral apposition rate, and osteoclast number were assessed.
  • Osteocyte autophagy, apoptosis, and bone turnover markers were analyzed.

Main Results:

  • Rapamycin treatment preserved trabecular bone structure and increased bone mineral density.
  • Rapamycin enhanced mineral apposition rate and reduced osteoclast numbers.
  • Increased autophagy markers (LC3) and reduced osteocyte apoptosis were observed in rapamycin-treated rats.

Conclusions:

  • Rapamycin partially ameliorates age-related bone changes in male rats by activating osteocyte autophagy.
  • The findings suggest rapamycin as a potential therapeutic strategy for senile osteoporosis.
Keywords:
AutophagyMale ratsOsteoporosisRapamycin

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