Effect of internal heat-type acupuncture on bone remodeling in a glucocorticoid-induced osteoporosis model rabbit by regulating the triplet of OPG-RANKL-RANK

Abstract

Introduction: Internal heat-type acupuncture therapy is a new therapeutic method that integrates acupuncture and heat therapy and effectively reduces local muscle inflammation. It has a good effect on the clinical application of osteoporosis. The purpose of this study was to assess the improvement of glucocorticoid-induced osteoporosis (GIOP) after internal heat-type acupuncture treatment as well as its role in promoting the balance of bone remodeling in the GIOP rabbit model by regulating the triplet of osteoprotegerin(OPG)-receptor activator of nuclear factor-KB ligand (RANKL)-receptor activator of nuclear factor-KB (RANK). Methods: The rabbits were divided into the control, model (GIOP), GIOP+Alendronate, and GIOP+Internal heat-type acupuncture groups, with 8 rabbits in each group. At the end of the treatment, all rabbits were sacrificed. The pathologic changes of lumbar vertebrae were observed by x-ray, the morphology of lumbar trabecular bone was observed by HE staining, and the apoptosis of lumbar vertebrae was detected by Tunel. The protein expressions of OPG, RANKL, and RANK in lumbar vertebrae were detected by immunohistochemistry staining, immunofluorescence staining, and Western blotting. Results: Internal heat-type acupuncture partly prevented osteopenia among GIOP-induced rabbits, improved the morphology of lumbar vertebrae, and inhibited the apoptosis of lumbar vertebrae osteocytes. Moreover, by increasing the protein expression level of OPG and reducing the protein expression of RANKL and RANK, internal heat-type acupuncture effectively promoted the balance of bone remodeling and eventually achieved the treatment of GIOP. Conclusion: Internal heat-type acupuncture therapy may promote the balance of bone remodeling by regulating the triplet of osteoprotegerin-receptor activator of nuclear factor-KB ligand-receptor activator of nuclear factor-KB, thereby treating osteoporosis which was induced by glucocorticoid.