Dataset Information

Interleukin-6 receptor blockade improves bone healing following ischemic osteonecrosis in adolescent mice.

ABSTRACT:

Objective

Juvenile ischemic osteonecrosis (JIO) of the femoral head is one of the most serious hip disorders causing a permanent deformity of the femoral head in childhood. We recently reported that interleukin 6 (IL-6) is significantly increased in the hip synovial fluid of patients with JIO and that articular chondrocytes are primary source of IL-6. Adolescent JIO is particularly challenging to treat and has poor outcome. This study determined if IL-6 receptor blockade prevents bone loss and improves the bone healing in adolescent JIO.

Method

Adolescent mice (12-week-old) surgically induced with JIO were treated with either saline or MR16-1, an IL-6 receptor blocker.

Results

Micro-CT assessment showed significantly increased bone volume (p < 0.001, Cohen's d = 2.0) and trabecular bone thickness (p < 0.001, d = 2.3) after the MR16-1 treatment. Histomorphometric assessment showed significantly increased osteoblast number (p < 0.01, d = 2.3), bone formation rate (p < 0.01, d = 4.3), and mineral apposition rate (p < 0.01, d = 4.1) after the MR16-1 treatment. The number of osteoclasts was unchanged. Histologic assessment showed significantly increased revascularization (p < 0.01) and restoration of the necrotic marrow with new hematopoietic bone marrow (p < 0.01). Vascular endothelial growth factor (VEGF) expression was increased in the revascularized area and the articular cartilage, and in the cultured chondrocytes treated with IL-6 receptor inhibitor.

Conclusion

IL-6 blockade in adolescent mice with JIO enhanced bone formation and revascularization. The findings suggest IL-6 receptor blocker as a potential medical therapy for adolescent JIO.

SUBMITTER: Kuroyanagi G

PROVIDER: S-EPMC10432805 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Publications

Interleukin-6 receptor blockade improves bone healing following ischemic osteonecrosis in adolescent mice.

Kuroyanagi Gen G Kamiya Nobuhiro N Yamaguchi Ryosuke R Kim Harry K W HKW

Osteoarthritis and cartilage open 20230802 4

<h4>Objective</h4>Juvenile ischemic osteonecrosis (JIO) of the femoral head is one of the most serious hip disorders causing a permanent deformity of the femoral head in childhood. We recently reported that interleukin 6 (IL-6) is significantly increased in the hip synovial fluid of patients with JIO and that articular chondrocytes are primary source of IL-6. Adolescent JIO is particularly challenging to treat and has poor outcome. This study determined if IL-6 receptor blockade prevents bone lo ...[more]

PMID: 37600923

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Dataset Information

Interleukin-6 receptor blockade improves bone healing following ischemic osteonecrosis in adolescent mice.

Objective

Method

Results

Conclusion

Publications

Interleukin-6 receptor blockade improves bone healing following ischemic osteonecrosis in adolescent mice.

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