Osteoblast Dysfunction in Non-Hereditary Sclerosing Bone Diseases

Effect of light walking combined with arthroscopic surgery on bone mineral density in patients with foot and ankle osteoarthritis

ObjectiveTo observe the effect of light walking combined with arthroscopic surgery on the efficacy and Bone Mineral Density (BMD) of patients with ankle arthritis. Methods 180 patients with ankle arthritis were retrospectively selected, who were divided into a control group (Group A) and an experimental group (Group B) according to treatment methods, with 90 patients in each group. Group A was treated with conventional open surgery and Group B was treated with light walking combined with arthroscopic surgery. The two groups were compared before and after treatment on scales such as the AOFAS ankle hindfoot score. Meanwhile, the patients' BMD and levels of inflammatory factors such as tumor cell necrosis factor-α (TNF-α) were compared before and after treatment. Results The Kofoed and AOFAS scale scores were higher for mild walking combined with arthroscopic surgery than for conventional treatment (P < 0.05), and their pain visual analogue VAS scores were lower than for conventional treatment (P < 0.05). In Group B, the postoperative BMD increase was significantly higher (P < 0.05). The R-value between PDGF bone growth factor and BMD was 0.957 and the R-value between VEGF growth factor and BMD was 0.903. The R-value between patient age and BMD was -0.936 and the R-value between patient BMI and BMD was -0.913. The treatment efficiency in Group B was 96.7 %. Conclusion The results prove that light walking combined with arthroscopic surgery is suitable for the surgical treatment of patients with ankle arthritis because it has a better therapeutic effect and makes patients' BMD level improved.

Regulation of bone homeostasis: signaling pathways and therapeutic targets

As a highly dynamic tissue, bone is continuously rebuilt throughout life. Both bone formation by osteoblasts and bone resorption by osteoclasts constitute bone reconstruction homeostasis. The equilibrium of bone homeostasis is governed by many complicated signaling pathways that weave together to form an intricate network. These pathways coordinate the meticulous processes of bone formation and resorption, ensuring the structural integrity and dynamic vitality of the skeletal system. Dysregulation of the bone homeostatic regulatory signaling network contributes to the development and progression of many skeletal diseases. Significantly, imbalanced bone homeostasis further disrupts the signaling network and triggers a cascade reaction that exacerbates disease progression and engenders a deleterious cycle. Here, we summarize the influence of signaling pathways on bone homeostasis, elucidating the interplay and crosstalk among them. Additionally, we review the mechanisms underpinning bone homeostatic imbalances across diverse disease landscapes, highlighting current and prospective therapeutic targets and clinical drugs. We hope that this review will contribute to a holistic understanding of the signaling pathways and molecular mechanisms sustaining bone homeostasis, which are promising to contribute to further research on bone homeostasis and shed light on the development of targeted drugs.

OP3-4 peptide sustained-release hydrogel inhibits osteoclast formation and promotes vascularization to promote bone regeneration in a rat femoral defect model

Bone injury caused changes to surrounding tissues, leading to a large number of osteoclasts appeared to clear the damaged bone tissue before bone regeneration. However, overactive osteoclasts will inhibit bone formation. In this study, we prepared methacrylylated gelatin (GelMA)-based hydrogel to co-crosslink with OP3-4 peptide, a receptor activator of NF-κB ligand (RANKL) binding agent, to achieve the slow release of OP3-4 peptide to inhibit the activation of osteoclasts, thus preventing the long-term existence of osteoclasts from affecting bone regeneration, and promoting osteogenic differentiation. Moreover, CXCL9 secreted by osteoblasts will bind to endogenous VEGF and inhibit vascularization, finally hinder bone formation. Thus, anti-CXCL9 antibodies (A-CXCL9) were also loaded in the hydrogel to neutralize excess CXCL9. The hydrogel slow released of OP3-4 cyclic peptide and A-CXCL9 to simultaneously inhibiting osteoclast activation and promoting vascularization, thereby accelerating the healing of femur defect. Further analysis of osteogenic protein expression and signal pathways showed that the hydrogel may be through activating the AKT-RUNX2-ALP pathway and ultimately promote osteogenic differentiation. This dual-acting hydrogel can effectively prevent nonunion caused by low vascularization and provide long-term support for the treatment of bone injury.