Osteoclast and Sclerostin Expression in Osteocytes in the Femoral Head with Risedronate Therapy in Patients with Hip Fractures: A Retrospective Comparative Study

• Published in: Medicina (Kaunas, Lithuania) Vol. 58; no. 11; p. 1566
• Main Authors: Lee, Hwan-Hee, Choi, Eun-Yong, Jun, Hyun-Sik, Kim, Young-Yul
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 31-10-2022; MDPI
• Subjects: Aged; Alcohol; Analysis; Antibodies; Bisphosphonates; Body mass index; Bone cells; Bone Density; Bones; Drug therapy; Female; femoral head; Femur Head; Fractures; hip fracture; Hip Fractures - drug therapy; Hip joint; Humans; Joint surgery; osteoclast; Osteoclasts; Osteocytes - metabolism; Osteoporosis; Osteoporosis - metabolism; Phosphatase; Prevention; Proteins; RANK Ligand - metabolism; Retrospective Studies; risedronate; Risedronic Acid - pharmacology; Risedronic Acid - therapeutic use; Risk factors; sclerostin; Japan; Chicago Illinois; St Louis Missouri; United Kingdom > UK; United States > US; femoral head; osteoclast; hip fracture; risedronate; sclerostin
• ISSN: 1648-9144; 1010-660X; 1648-9144
• DOI: 10.3390/medicina58111566

Background and Objectives: The majority of research on the effects of osteoporosis drugs has measured the bone mineral density (BMD) of the spine and femur through dual-energy X-ray absorptiometry (DEXA) and compared and analyzed the effects of the drugs through changes in the BMD values. This study aims to compare osteoclast and sclerostin expression in osteocytes after risedronate therapy by obtaining femoral heads from patients with hip fractures. Materials and Methods: We obtained the femoral heads of 10 female patients (age: ≥65 years) who received risedronate therapy for at least 1 year through hip arthroplasty during 2019−2021 (risedronate group). Meanwhile, 10 patients who had never received osteoporosis treatment were selected as controls using propensity scores with age, body mass index, and bone density as covariates (control group). While the osteoclast count was evaluated using tartrate-resistant acid phosphatase (TRAP) staining, the sclerostin expression in osteocytes was assessed using immunohistochemistry. Moreover, Western blotting and polymerase chain reaction (PCR) were performed for receptor activation of nuclear factor kappa-Β ligand (RANKL), RANK, osteoprotegerin (OPG), sclerostin, and bone morphogenetic protein-2 (BMP2). Results: TRAP staining revealed significantly more TRAP-positive cells in the control group (131.75 ± 27.16/mm2) than in the risedronate group (28.00 ± 8.12/mm2). Moreover, sclerostin-positive osteocytes were expressed more in the control group (364.12 ± 28.12/mm2) than in the risedronate group (106.93 ± 12.85/mm2). Western blotting revealed that the expressions of RANKL, RANK, sclerostin, and BMP2 were higher in the control group than in the risedronate group (p < 0.05). Furthermore, RANK, sclerostin, and OPG protein levels were higher in the control group than in the risedronate group. Conclusions: In this study, the risedronate group demonstrated lower osteoclast activity and sclerostin expression in osteocytes in the femoral head than the control group.