TITLE:
Combination of simvastatin and hydroxyapatite fiber induces bone augmentation
AUTHORS:
Shang Gao, Makoto Shiota, Masaki Fujii, Kang Chen, Masahiro Shimogishi, Masashi Sato, Shohei Kasugai
KEYWORDS:
Biomaterial; Bone Substitutes; Bone Formation; Drug Delivery; Growth Factors
JOURNAL NAME:
Open Journal of Regenerative Medicine,
Vol.2 No.3,
August
21,
2013
ABSTRACT: This study evaluated the capability of hydroxyapatite fiber (HAF) as a carrier and the bone formation by blending simvastatin.
The mixture of HAF and simvastatin (0.15, 0.45, 0.75 mg) was placed in 1 ml of
tris-buffer and the release of simvastatin from HAF was calculated per 24 hours
for 10 days. Bilateral 5 mm-diameter and 3 mm-hight Teflon chambers were fixed
on calvaria of adult Japanese white rabbits and filled with 40 mg HAF which
containing simvastatin (0, 0.15, 0.45, 0.75 mg). The animals were sacrificed at
4 and 8 weeks and calculated radiologically by Micro-CT. After dyeing by toluidine
blue the samples were analyzed histologically. In all of the study groups
approximately 25% of simvastatin was released until 10 days. The new bone
volume ratio measured by Micro-CT of 4 and 8 weeks group was (22.4%, 21.3%,
41.6%, 26.3%) and (20.2%, 11.7%, 42.1%, 31.2%) in different doses respectively. The 0.45 mg group showed significantly
higher new bone volume ratio than 0 mg group and 0.15 mg group. The
histological measurement and observations also supported these results.
In conclusion, the HAF could be used as a carrier for simvastatin. Combinations
of HAF and simvastatin have the potentiality to stimulate new bone formation
and approximately 0.45 mg simvastatin in 40 mg HAF is the optimal dose in
rabbit chamber model.