COMP-Angiopoietin-1 ameliorates surgery-induced ischemic necrosis of the femoral head in rats.
BACKGROUND
Ischemic necrosis of the femoral head (INFH) can lead to loss of femoral head architecture and deformity. Moreover, the process of bone healing is intimately associated with angiogenesis. We considered that COMP-Ang1 (an angiogenic factor) might preserve femoral head structure and facilitate bone repair.


METHODS
INFH was induced in the femoral head of rats by dissecting the cervical periosteum and placing a ligature tightly around the femoral neck. Two weeks later, COMP-Ang1 was injected directly into infarcted areas. Rats were divided into the following groups; 1) the sham-operated group (the sham group), 2) the bovine serum albumin-injected group (the BSA group), and 3) the COMP-Ang1-injected group (the COMP-Ang1 group) (n=20/group). At 8 weeks post-surgery animals were sacrificed and radiologic and histomorphometric assessments were performed.


RESULTS
Radiographs obtained at 8 weeks post-surgery showed better preservation of femoral head architecture in the COMP-Ang1 group than in the BSA group. Histological findings and immunostainings of endothelial cells for factor VIII revealed that COMP-Ang1 group animals showed higher levels of vascularity in the secondary ossification center of infarcted femoral heads.


CONCLUSIONS
When INFH was surgically induced in rats, an intraosseous injection of COMP-Ang1 preserved the trabecular framework of the osseous epiphysis and prevented femoral head deformities by promoting angiogenesis and bone remodeling.
Department of Biochemistry, Medical School and Research Institute of Clinical Medicine, Chonbuk National University, Jeonju, Jeonbuk, Republic of Korea.
Byung-Hyun
BH
Park
Kyu Yun
KY
Jang
Kyu Hyung
KH
Kim
Kwang Hun
KH
Song
Sang Yong
SY
Lee
Sun Jung
SJ
Yoon
Keun Sang
KS
Kwon
Wan-Hee
WH
Yoo
Young Jun
YJ
Koh
Kwon Ha
KH
Yoon
Hyun Hwa
HH
Son
Gou Young
GY
Koh
Jung Ryul
JR
Kim
D042683:Angiopoietin-1 / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D005270:Femur Head / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000473:pathology / Q000601:surgery*; D005271:Femur Head Necrosis / Q000000981:diagnostic imaging / Q000188:drug therapy*; D007150:Immunohistochemistry; D017148:Infusions, Intraosseous; D008297:Male; D018919:Neovascularization, Physiologic / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects; D011859:Radiography; D051381:Rats; D017207:Rats, Sprague-Dawley
D042683:Angiopoietin-1