Anti-sclerostin antibodies: a new frontier in fragility fractures treatment

Male osteoporosis: the impact of lifestyle, from nutrition to physical activity

Male osteoporosis is an increasing worldwide pathological condition, characterized by an increased risk of fragility fractures, that is underestimated, underdiagnosed and undertreated. Prevention and treatment play a pivotal role in reducing fractures, and it is important to remember that therapeutic interventions include balanced nutrition and physical activity. Pharmacological treatments are the main and most effective tool to achieve numerous and decisive benefits in this population. Among these, testosterone replacement therapy, when allowed by circumstances and comorbidities, is useful. Anyway, the main goal is always to start from lifestyle, including nutrition and physical activity, plays a very important and crucial role. The many pieces of this puzzle, called lifestyle, need to be accurately collected and grouped carefully, in order to be able to have a broad picture of what needs to be integrated and what is sufficient for the ultimate purpose of enabling each individual man to have a sufficient basic health point. Thus, the purpose of this short narrative review is to highlight the preventive and therapeutic role of lifestyle components, particularly nutrition and physical activity, in males with osteoporosis. Finally, an evaluation of the impact of the main current diets used in recent years and the main physical activities as strategies for the safety of male bone health.

Romosozumab versus denosumab in long-term users of glucocorticoids: A pilot randomized controlled trial

OBJECTIVE

To compare the efficacy of romosozumab (ROMO) and denosumab (DEN) in prevalent long-term glucocorticoid (GC) users.

METHODS

Adult patients receiving oral prednisolone (≥5 mg/day) with high risk of fracture were randomized to receive subcutaneous ROMO (210 mg monthly) or DEN (60 mg 6-monthly) for 12 months, followed by DEN for two more doses. The primary end point was the change in spine bone mineral density (BMD) from Months 0 to 12. Secondary end points included changes in BMD of the spine/hip/femoral neck and bone turnover markers at various time points and adverse events.

RESULTS

Seventy patients (age 62.6 ± 9.1 years; 96% women; median prednisolone dose 5.0 mg/day; duration of therapy 10.7 ± 7.4 years) were enrolled, and 63 completed the study. At Month 12, the spine BMD increased significantly in both ROMO (+7.3% ± 4.5%; p < 0.001) and DEN (+2.3% ± 3.1%; p < 0.001) groups. The absolute spine BMD gain from Months 0 to 12 was significantly greater in ROMO-treated patients (p < 0.001). Although the total hip BMD at Month 12 also increased significantly in the ROMO (+1.6% ± 3.3%; p = 0.01) and DEN groups (+1.6% ± 2.6%; p = 0.003), the absolute BMD gain was not significantly different between the groups. At Month 24, the spine BMD continued to increase in both the ROMO (+9.7% ± 4.8%; p < 0.001) and DEN group (+3.0% ± 3.0%; p < 0.001) compared to baseline, and the absolute BMD gain remained significantly greater in ROMO-treated patients. The total hip BMD continued to increase in both groups (ROMO +2.9% ± 3.7%; p < 0.001; DEN +2.2% ± 3.4%; p = 0.001), but the changes from baseline were similar. Injection site reaction was more frequently reported in ROMO-treated patients.

CONCLUSION

ROMO was superior to DEN in raising the spine BMD at Month 12 in chronic GC users. After switching to DEN, ROMO-treated patients continued to gain spine BMD to a greater extent than DEN until Month 24.

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.

Association of serum sclerostin levels with marrow adiposity in postmenopausal women with glucocorticoid-induced osteoporosis

BACKGROUND

Glucocorticoids and sclerostin act as inhibitors of the Wnt signaling pathway, thereby hindering bone formation. Given the pathway's intricate association with mesenchymal stem cells, the hypothesis suggests that heightened sclerostin levels may be intricately linked to an augmentation in marrow adiposity induced by glucocorticoids. This study endeavored to delve into the nuanced relationship between circulating sclerostin and bone marrow adipose tissue in postmenopausal women grappling with glucocorticoid-induced osteoporosis (GIO).

METHODS

In this cross-sectional study, 103 patients with autoimmune-associated diseases underwent glucocorticoid treatment, boasting an average age of 61.3 years (standard deviation 7.1 years). The investigation encompassed a thorough assessment, incorporating medical history, anthropometric data, biochemical analysis, and dual-energy X-ray absorptiometry measurements of lumbar and femoral bone mineral density (BMD). Osteoporosis criteria were established at a T-score of -2.5 or lower. Additionally, MR spectroscopy quantified the vertebral marrow fat fraction.

RESULTS

BMD at the femoral neck, total hip, and lumbar spine showcased an inverse correlation with marrow fat fraction (r = -0.511 to - 0.647, P < 0.001). Serum sclerostin levels exhibited a positive correlation with BMD at various skeletal sites (r = 0.476 to 0.589, P < 0.001). A noteworthy correlation emerged between circulating sclerostin and marrow fat fraction at the lumbar spine (r = -0.731, 95% CI, -0.810 to -0.627, P < 0.001). Multivariate analysis brought to light that vertebral marrow fat fraction significantly contributed to sclerostin serum concentrations (standardized regression coefficient ß = 0.462, P < 0.001). Even after adjusting for age, body mass index, physical activity, renal function, BMD, and the duration and doses of glucocorticoid treatment, serum sclerostin levels maintained a significant correlation with marrow fat fraction.

CONCLUSIONS

Circulating sclerostin levels exhibited a noteworthy association with marrow adiposity in postmenopausal women grappling with GIO.

Bone involvement in the early stages of Parkinson's disease: a case-control study

OBJECTIVE

To evaluate the qualitative and quantitative alterations of bone tissue in patients with early-stage Parkinson's disease (PD) and to measure the associations between bone mineral density (BMD), trabecular bone score (TBS) and physical performance.

METHODS

This case-control study enrolled patients with early-stage PD and age-matched controls. BMDs for the left femoral neck (L-FN) and lumbar spine (LS) were measured. Bone microarchitecture for the LS was determined using TBS. Muscle performance was assessed using the short physical performance battery (SPPB). Patients and controls were stratified in two groups based on the SPPB score: a poor performance group (SPPB score ≤8) and high performance group (SPPB > 8).

RESULTS

This study included 26 patients: 13 in the PD group and 13 age-matched controls. The mean ± SD BMD results in the PD group were: L1-L4 BMD = 0.935 ± 0.183 g/cm2; L-FN BMD = 0.825 ± 0.037 g/cm2; with bone microarchitecture degraded in four patients and partially degraded in three patients. TBS was significantly different in the patients with PD stratified according to SPPB. Among the controls, there was a significant difference in body mass index between the two SPPB groups.

CONCLUSION

TBS might identify bone involvement earlier than BMD in the initial stages of PD.

Alfacalcidol-Induced Kidney Injury in Patients with Severe Motor and Intellectual Disabilities

Patients with severe motor and intellectual disabilities (SMID) often experience insufficient physical activity, leading to osteoporosis. The active form of vitamin D is commonly prescribed for the prevention or treatment of osteoporosis. We observed four cases of kidney injury believed to be associated with the administration of 1α-OH vitamin D (alfacalcidol) preparations. This study employed a case series design to investigate change in kidney function in SMID patients following administration or discontinuation of alfacalcidol. We retrospectively analyzed data of 23 SMID patients (sex: 10 males, 13 females; age range: 27 to 74 y), and assessed kidney function, serum calcium, and albumin levels. Data was grouped into A: 16 cases collected both before starting alfacalcidol administration and during alfacalcidol administration; and into B: 11 cases collected during alfacalcidol administration and after discontinuation of alfacalcidol administration. Of the 23 patients, four were assigned into both group A and group B. Of the 16 cases in group A, six showed ≥30% decreased kidney function. Of the 11 cases in group B, the median values of modified Cr-eGFR were 43.0 and 65.1 mL/min/1.73 m2, respectively (p=0.008), indicating a significant improvement in kidney function. It is essential for practitioners to understand that osteoporosis may ordinarily occur in SMID patients due to reduced bone stimulation. Thus caution must be exercised when administering active vitamin D preparations to this population, as they carry a risk of kidney organ damage despite having no direct effect on bone health.

Difficulties in decision making on a long standing, complicated case of osteoporosis – a real challenge for functional rehabilitation

We aim was to present a case of severe osteoporosis with concern to an adult female who was under specific medication against the condition while she experienced inexplicable weight loss in association with an incidental fracture inconsistent with DXA changes. Challenges of the case management and decision making are further on explained. Real-life-medicine poses multiple issues that require an individual decision while respecting the standard protocols. That is why a generalized decision is rather impractical. Here we introduce the clinical case of a lady in her late 60s with a known 6-year history of osteoporosis that required several difficult decisions along surveillance: at first, zoledronic acid represented an available solution, yet after one year, BMD decreased and adjustment was done by initiating a second sequence according to the teriparatide protocol. DXA-BMD, as well as the spectrum of bone turnover markers, qualified the patient as responsive and she further continued with oral bisphosphonates while being monitored via telemedicine amid COVID-19 pandemic. After 24 more months, a second decision of zoledronic acid was done, despite prior partial response, but digestive complains restricted the oral administration of anti-osteoporotic drugs. After one more year, denosumab was initiated and consecutive follow-up is essential. At this point, another challenging aspect was revealed: the discordance between DXA – based scores increase and the presence of an incidental fracture. A supplementary investigation was considered useful (Tc- whole body scintigraphy) noting the clinical presentation with local pain, dysfunctionality, and mild weight loss that also required rehabilitation management.

Molecular and Cellular Mechanisms of Osteoporosis

Osteoporosis is a widespread systemic disease characterized by a decrease in bone mass and an imbalance of the microarchitecture of bone tissue. Experimental and clinical studies devoted to investigating the main pathogenetic mechanisms of osteoporosis revealed the important role of estrogen deficiency, inflammation, oxidative stress, cellular senescence, and epigenetic factors in the development of bone resorption due to osteoclastogenesis, and decreased mineralization of bone tissue and bone formation due to reduced function of osteoblasts caused by apoptosis and age-depended differentiation of osteoblast precursors into adipocytes. The current review was conducted to describe the basic mechanisms of the development of osteoporosis at molecular and cellular levels and to elucidate the most promising therapeutic strategies of pathogenetic therapy of osteoporosis based on articles cited in PubMed up to September 2023.