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Culture of Murine Embryonic Metatarsals: A Physiological Model of Endochondral Ossification
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The NO-cGMP-PKG pathway in skeletal remodeling.
Se-Min Kim1, Tony Yuen1, Jameel Iqbal1
1The Mount Sinai Bone Program, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.
Annals of the New York Academy of Sciences
|August 30, 2020
Summary
Targeting phosphodiesterase type 5 A (PDE5A) inhibitors may offer a new therapeutic strategy for osteoporosis. Inhibiting PDE5A may enhance bone formation and protect against bone loss, warranting further investigation.
Area of Science:
- Biochemistry
- Bone Biology
- Pharmacology
Background:
- The nitric oxide (NO)-cyclic guanosine monophosphate (cGMP)-protein kinase G (PKG) pathway is crucial for skeletal homeostasis.
- NO's role in bone remodeling and mediating anabolic effects of mechanical stimuli and estrogen is established, but its clinical use for osteoporosis is limited by side effects and tachyphylaxis.
Purpose of the Study:
- To explore the potential of targeting downstream components of the NO-cGMP-PKG pathway for osteoporosis treatment.
- To investigate the role of phosphodiesterase type 5 A (PDE5A) in skeletal tissue and the therapeutic potential of PDE5A inhibitors.
Main Methods:
- Review of preclinical data, including in vitro and in vivo studies.
- Analysis of the expression of PDE5A in skeletal tissue.
- Evaluation of the potential of PDE5A inhibitors to modulate the NO-cGMP-PKG pathway for bone health.
Main Results:
- PDE5A is highly expressed in skeletal tissue.
- Inhibiting PDE5A may enhance osteoanabolic signaling and provide skeletal protection.
- Preclinical data suggest PDE5A inhibitors could be repurposed for osteoporosis treatment.
Conclusions:
- Targeting PDE5A represents a promising therapeutic avenue for osteoporosis.
- Further research is required to identify the primary bone cells affected, elucidate direct/indirect mechanisms, and understand changes in skeletal PDE5A expression in aging and disease models.
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