Osteoporosis: From Molecular Mechanisms to Therapies 3.0

Osteoporosis is a common skeletal disorder that occurs as a result of an imbalance between bone resorption and bone formation, with bone breakdown exceeding bone building. Bone resorption inhibitors, e.g., bisphosphonates, have been designed to treat osteoporosis. Teriparatide, an anabolic agent, stimulates bone formation and corrects the characteristic changes in the trabecular microarchitecture. However, these drugs are associated with significant side effects. It is therefore crucial that we continue to research the pathogenesis of osteoporosis and seek novel modes of therapy. This editorial summarizes and discusses the themes of the six articles published in our Special Issue “Osteoporosis: From Molecular Mechanisms to Therapies 3.0”, a continuation of our 2020 Special Issue "Osteoporosis: From Molecular Mechanisms to Therapies". These Special Issues detail important global scientific findings that contribute to our current understanding of osteoporosis.

Some aspects of the use of oral contraceptives as growth-promoting agents in poultry

There are now several hormone and hormone-like agents that can improve the rate of growth and efficiency of feed use of farm animals. Feeding chickens with oral contraceptive steroids at the dose used by some poultry growers in Egypt has led to the formation of high estrogen residues in the muscles and the liver compared with controls. Electron microscopy of the livers of treated chickens revealed changes at the ultrastructural level. These alterations involve both the nucleus and cytoplasmic organelles, and are similar to those induced by 7, 12 dimethylbenz [a] anthracene in chickens. It is concluded that the use of oral contraceptive steroids in chickens as anabolic agent is a specific risk to chickens and probably to the consumer

Augmentation of implant surfaces with BMP-2 in a revision setting

Aims We wanted to evaluate the effects of a bone anabolic agent (bone morphogenetic protein 2 (BMP-2)) on an anti-catabolic background (systemic or local zoledronate) on fixation of allografted revision implants. Methods An established allografted revision protocol was implemented bilaterally into the stifle joints of 24 canines. At revision surgery, each animal received one BMP-2 (5 µg) functionalized implant, and one raw implant. One group (12 animals) received bone graft impregnated with zoledronate (0.005 mg/ml) before impaction. The other group (12 animals) received untreated bone graft and systemic zoledronate (0.1 mg/kg) ten and 20 days after revision surgery. Animals were observed for an additional four weeks before euthanasia. Results No difference was detected on mechanical implant fixation (load to failure, stiffness, energy) between local or systemic zoledronate. Addition of BMP-2 had no effect on implant fixation. In the histomorphometric evaluation, implants with local zoledronate had more area of new bone on the implant surface (53%, p = 0.025) and higher volume of allograft (65%, p = 0.007), whereas implants in animals with systemic zoledronate had the highest volume of new bone (34%, p = 0.003). Systemic zoledronate with BMP-2 decreased volume of allograft by 47% (p = 0.017). Conclusion Local and systemic zoledronate treatment protects bone at different stages of maturity; local zoledronate protects the allograft from resorption and systemic zoledronate protects newly formed bone from resorption. BMP-2 in the dose evaluated with experimental revision implants was not beneficial, since it significantly increased allograft resorption without a significant compensating anabolic effect. Cite this article: Bone Joint Res 2021;10(8):488–497.

Testosterone undecanoate injection, a rare cause of diffuse alveolar hemorrhage: A case report from Almoosa Hospital

Many systemic and few respiratory (cough, pulmonary embolism) adverse effects follow anabolic agent use. Pulmonary hemorrhage is not considered one among them. We present a case of an adult Saudi male who developed diffuse alveolar hemorrhage (DAH) as a results of the utilization of injectable anabolic steroid hormone replacement therapy. The literature reported only three cases of DAH related to anabolic agent abuse. The patient was presented with acute dyspnea and hemoptysis with diffuse alveolar shadow on chest radiograph. The symptoms promptly resolved with cessation of exposure and recurrent after the reuse. Pulmonary hemorrhage as an acute complication of anabolic agent use must be considered when clinical and radiological findings support it. It's important to rule out the autoimmune and infectious-related causes before considering it drug-related.

Patients Risk Stratification in the Management of Osteoporosis: the Latest International Guidelines

Assessment of risk of a fragility fracture is a vital step a physician needs to undertake in every patient suspected of osteoporosis, as this will influence the decisions on whether to treat with a pharmacological agent, with which drug, and for how long. After risk stratification, patients deemed Very High-Risk should be considered for an anabolic agent, or if this is not feasible, a parenteral anti-resorptive. High- Risk or Moderate-Risk patients may be considered for oral bisphosphonates.

Osteoporosis: From Molecular Mechanisms to Therapies 2.0

Osteoporosis is a common skeletal disorder, occurring as a result of an imbalance between bone resorption and bone formation, with bone breakdown exceeding bone building. Bone resorption inhibitors, e.g., bisphosphonates, have been designed to treat osteoporosis. Teriparatide, an anabolic agent, stimulates bone formation and corrects the characteristic changes in the trabecular microarchitecture. However, these drugs are associated with significant side effects. It is therefore crucial that we continue to research the pathogenesis of osteoporosis and seek novel modes of therapy. This editorial summarizes and discusses the themes of the ten articles published in our Special Issue “Osteoporosis: From Molecular Mechanisms to Therapies 2.0”, a continuation of our 2019 Special Issue "Osteoporosis: From Molecular Mechanisms to Therapies" (https://www.mdpi.com/journal/ijms/special_issues/osteoporosis_ijms). These Special Issues detail important global scientific findings that contribute to our current understanding of osteoporosis.

Treatment of Medication-Related Osteonecrosis of the Jaw Around the Dental Implant With a Once-Weekly Teriparatide: A Case Report and Literature Review

Managing medication-related osteonecrosis of the jaw (MRONJ) around a dental implant can be difficult. Although conservative treatment of MRONJ is recommended as the first-line form of management, many patients exhibit no improvement. The human recombinant parathyroid hormone teriparatide has recently been introduced for the management of MRONJ. Teriparatide is effective in the treatment of postmenopausal osteoporosis and is the only US Food and Drug Administration–approved anabolic agent that directly affects osteoblast function and contributes to bone remodeling. Herein we describe a case of MRONJ in an 85-year-old woman who was successfully treated with teriparatide. Teriparatide was administered once per week without any surgical interventions such as a sequestrectomy. Compared with most recently reported cases involving daily treatment with teriparatide, once-weekly administration of teriparatide may minimize side effects and patient discomfort. Once-weekly teriparatide application without sequestrectomy may be effective in the management of MRONJ around a dental implant.