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03:57
Generation of Hypoparathyroid Rats via Carbon-Nanoparticle-Assisted Parathyroidectomy
Published on: July 14, 2023
Treating osteoporosis by targeting parathyroid hormone to bone
T Ponnapakkam1, R Katikaneni1, J Sakon2
1Pediatric Endocrinology, Children's Hospital at Montefiore and Albert Einstein College of Medicine, Bronx, NY, USA.
Drug Discovery Today
|August 13, 2013
Summary
New bone-targeting parathyroid hormone (PTH-CBD) therapy shows promise for osteoporosis treatment. Monthly injections increased bone density in rats without causing hypercalcemia, offering a potentially safer and more convenient anabolic option.
Area of Science:
- Biomedical Engineering
- Endocrinology
- Orthopedics
Background:
- Osteoporosis presents a significant public health challenge, with current bisphosphonate treatments having limitations.
- While parathyroid hormone (PTH(1-34)) is more effective, its clinical use is restricted by side effects like hypercalcemia and tumor risk, alongside inconvenient daily injections.
- Existing long-acting PTH formulations also induce severe hypercalcemia, likely due to renal effects.
Purpose of the Study:
- To investigate the potential of a bone-targeted parathyroid hormone (PTH) delivery system, PTH-CBD, to mitigate hypercalcemia while maintaining therapeutic efficacy.
- To evaluate the safety and effectiveness of monthly PTH-CBD administration in an established animal model of osteoporosis.
Main Methods:
- Development of a novel PTH-CBD conjugate designed for targeted delivery to bone via a collagen-binding domain.
- Pharmacokinetic analysis of PTH-CBD serum clearance following subcutaneous administration.
- Assessment of spinal bone mineral density (BMD) changes and serum calcium levels in ovariectomized rats after monthly PTH-CBD treatment.
Main Results:
- PTH-CBD demonstrated rapid serum clearance within 12 hours post-administration.
- Monthly subcutaneous administration of PTH-CBD resulted in a significant 14.2% increase in spinal BMD in ovariectomized rats.
- Crucially, PTH-CBD treatment was not associated with any observable hypercalcemia.
Conclusions:
- Targeted delivery of PTH to bone using a collagen-binding domain (PTH-CBD) effectively increases bone mineral density.
- PTH-CBD represents a promising therapeutic strategy for osteoporosis, potentially combining the superior efficacy of anabolic agents with improved safety and dosing convenience.
- This bone-targeting approach may overcome the dose-limiting hypercalcemia associated with other PTH formulations, paving the way for more convenient anabolic therapies.
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