RESUMEN
Osteoanabolic-first treatment sequences are superior to oral bisphosphonates for fracture reduction and BMD gain. However, data comparing osteoanabolic medications with the more potent antiresorptive, denosumab (DMAb), are limited. We analyzed FRAME and FRAME Extension data to assess BMD and fracture incidence in patients treated with romosozumab (Romo) followed by DMAb (Romo/DMAb) versus DMAb (DMAb/DMAb) for 24 months. In FRAME, women aged ≥55 years (total hip [TH] or femoral neck [FN] T-score: -2.5 to. -3.5) were randomized to Romo or placebo for 12 months followed by DMAb for 12 months. In FRAME Extension, both cohorts received DMAb for another 12 months. This post-hoc analysis compared BMD change and fracture incidence in patients on Romo/DMAb (months 0-24) versus DMAb/DMAb (months 12-36). Patient characteristics were balanced by propensity score weighting (PSW) and sensitivity analyses were conducted using PSW with multiple imputation (PSW-MI) and propensity score matching (PSM). Unmeasured confounding was addressed using E-values. After PSW, over 24 months, compared with DMAb/DMAb, treatment with Romo/DMAb produced significantly greater BMD increases at the lumbar spine [LS], TH, and FN (mean differences: 9.3%, 4.4%, and 4.1%, respectively; all p < 0.001). At month 24, in women with a baseline T-score of -3.0, the probability of achieving a T-score > -2.5 was higher with Romo/DMAb versus DMAb/DMAb (LS:92% versus 47%; TH:50% versus 5%). In the Romo/DMAb versus DMAb/DMAb cohorts, new vertebral fractures were significantly reduced (0.62% versus 1.26% [odds ratio = 0.45; p = 0.003]) and rates of clinical, nonvertebral, and hip fractures were lower (differences not significant). Similar BMD and fracture outcomes were observed with PSW-MI and PSM sensitivity analyses. The sequence of Romo/DMAb resulted in greater BMD gains and higher probability of achieving T-scores > -2.5, significantly reduced new vertebral fracture incidence, and numerically lowered the incidence (not significant) of clinical, nonvertebral, and hip fractures versus DMAb only through 24 months.
In patients with very high fracture risk, a treatment sequence with a bone-forming agent, followed by a bisphosphonate (one type of antiresorptive that reduces bone loss) is more effective in increasing bone mineral density (BMD) and reducing fracture risk compared to treatment with bisphosphonates alone. Here, we utilized patient data from the FRAME and FRAME Extension clinical trials to compare changes in BMD and fracture incidence in postmenopausal women with osteoporosis treated with the bone-forming agent, romosozumab (Romo), for 12 months followed by the most potent antiresorptive, denosumab (DMAb), for 12 months (Romo/DMAb) versus patients treated with DMAb alone for 24 months. Propensity score weighting was used to balance the patient characteristics between the two groups. We found that BMD gains were significantly higher in patients treated with the Romo/DMAb sequence versus DMAb alone; these patients also had a higher probability of achieving a T-score above the osteoporosis range (>2.5). In addition, new vertebral fractures were significantly lower and rates of clinical, nonvertebral, and hip fractures trended lower in patients treated with the Romo/DMAb sequence versus DMAb alone. Thus, a 24-months treatment sequence of Romo/DMAb compared with DMAb alone, resulted in higher BMD gains and lower fracture risk.
RESUMEN
Romosozumab, a humanized monoclonal antibody that binds and inhibits sclerostin produces a marked increase in bone formation with a concomitant decreased bone resorption. This transient rise in bone formation in the first two months of treatment is mainly due to an increased modeling-based bone formation. This requires the recruitment and differentiation of osteoblasts, one possibility being a preferential switch in commitment of precursors to osteoblasts over adipocytes. The purpose of this study was to analyze the marrow adiposity in transiliac bone biopsies at months 2 or 12 from the FRAME biopsy sub-study in patients receiving romosozumab or placebo. The total adipocyte area, number and density were measured on the total cancellous bone area. The size and shape at the individual adipocyte level were assessed including the mean adipocyte area, perimeter, min and max diameters and aspect ratio. No significant difference in total adipocyte area, number or density between placebo and romosozumab groups was observed at months 2 and 12, and no difference was observed between 2 and 12 months. After 2 or 12 months, romosozumab did not modify the size or shape of the adipocytes. No relationship between the adipocyte parameters and the dynamic parameters of bone formation could be evidenced. In conclusion, based on the analysis of a small number of biopsies, no effect of romosozumab on bone marrow adiposity of iliac crest was identified after 2 and 12 months suggesting that the modeling-based formation observed at month 2 was not due to a preferential commitment of the precursor to osteoblast over adipocyte cell lines but may result from a reactivation of bone lining cells and from a progenitor pool independent of the marrow adipocyte population.
Osteoporosis is characterized by bone loss resulting from an imbalance between the bone resorption and the bone formation in favor of the resorption. Romosozumab, a new medication to treat osteoporosis, has been shown to induce an early transient increase in bone formation that requires the differentiation of new bone forming cells called osteoblasts. Osteoblasts and fat-containing cells known as adipocytes present in the bone marrow originate from a common precursor cell. Thus, a preferential switch of this precursor to osteoblast over adipocyte is thought to be a possible cause for the increase in bone formation. The purpose of this study was to analyze the bone marrow adipocytes on bone biopsies from the pelvis in osteoporotic patients treated with romosozumab in order to evaluate that possibility. After treatment, the proportion of adipocytes, their size and shape, did not change when compared to untreated patients. In conclusion, no effect of romosozumab on bone marrow adipocytes was identified suggesting that the increased bone formation induced by romosozumab was not due to a preferential differentiation of precursor cells to osteoblasts over adipocytes.
RESUMEN
The overarching goal of osteoporosis management is to prevent fractures. A goal-directed approach to long-term management of fracture risk helps ensure that the most appropriate initial treatment and treatment sequence is selected for individual patients. Goal-directed treatment decisions require assessment of clinical fracture history, vertebral fracture identification (using vertebral imaging as appropriate), measurement of bone mineral density (BMD) and consideration of other major clinical risk factors. Treatment targets should be tailored to each patient's individual risk profile and based on the specific indication for beginning treatment, including recency, site, number and severity of prior fractures, and BMD levels at the total hip, femoral neck, and lumbar spine. Instead of first-line bisphosphonate treatment for all patients, selection of initial treatment should focus on reducing fracture risk rapidly for patients at very high and imminent risk, such as in those with recent fractures. Initial treatment selection should also consider the probability that a BMD treatment target can be attained within a reasonable period of time and the differential magnitude of fracture risk reduction and BMD impact with osteoanabolic versus antiresorptive therapy. This position statement of the ASBMR/BHOF Task Force on Goal-Directed Osteoporosis Treatment provides an overall summary of the major clinical recommendations about treatment targets and strategies to achieve those targets based on the best evidence available, derived primarily from studies in older postmenopausal women of European ancestry.
Goal-directed treatment can help healthcare providers recommend the best treatments for individual patients to prevent fractures. The goal-directed strategy considers the site, number and recency of prior fractures. This may require imaging for spine fractures, which may not have caused pain. Treatment decisions also require bone mineral density (BMD) measurement and consideration of other major risk factors. In contrast to the standard approach, same first treatment for all, treatment selection is tailored to an individual's risk. In patients with recent fractures of the spine, hip or pelvis, fracture risk is very high and treatment should rapidly reduce that risk. For others, the target is a specific BMD level and should consider the likelihood that the treatment target can be attained within a reasonable period of time, which differs for osteoporosis medications. After initial therapy, BMD should be assessed to determine if the target has been achieved. If so, strategies should focus on maintaining BMD. If the target is not yet achieved, treatment should be intensified, or continued if it is already the most potent option. This position statement represents a consensus of expert recommendations about treatment targets and strategies to achieve those targets based on the best available evidence.
RESUMEN
Low back pain derived from intervertebral disc (IVD) degeneration is a debilitating spinal condition that, despite its prevalence, does not have any intermediary guidelines for pharmacological treatment between palliative care and invasive surgery. The development of treatments for the IVD is complicated by the variety of resident cell types needed to maintain the regionally distinct structural properties of the IVD that permit the safe, complex motions of the spine. Osteoporosis of the spine increases the risk of vertebral bone fracture that can increase the incidence of back pain. Fortunately, there are a variety of pharmacological treatments for osteoporosis that target osteoblasts, osteoclasts and/or osteocytes to build bone and prevent vertebral fracture. Of particular note, clinical and preclinical studies suggest that commonly prescribed osteoporosis drugs like bisphosphonates, intermittent parathyroid hormone, anti-sclerostin antibody, selective estrogen receptor modulators and anti-receptor activator of nuclear factor-kappa B ligand inhibitor denosumab may also relieve back pain. Here, we cite clinical and preclinical studies and include unpublished data to support the argument that a subset of these therapeutics for osteoporosis may alleviate low back pain by also targeting the IVD.
RESUMEN
BACKGROUND: Romosozumab, a fully humanized anti-sclerostin-antibody, is a bone-builder stimulating osteoblasts and inhibiting osteoclast by activation of the canonical Wnt-beta catenin signaling. This unique mechanism of action has the potential to address unmet needs in osteoporosis management. METHODS: The multifaceted practical clinical issues related to romosozumab are discussed, especially focusing on the rationale of employing a sclerostin inhibitor to target bone fragility as first line or second line treatment in post-menopausal osteoporosis and in males at increased risk of fractures. RESULTS: Four randomized clinical trials with several post-hoc analyses and more than ten observational studies have consistently demonstrated that romosozumab is effective in rapidly increasing bone mineral density (BMD) and decreasing risk of vertebral, non-vertebral and hip fractures in post-menopausal women at very-high risk of fractures. In male osteoporosis, only data on BMD are available. Noteworthy, romosozumab was shown to be more effective and rapid than teriparatide in improving BMD, bone structure and strength at the hip, especially in women already treated with anti-resorptive drugs. Interestingly, even if romosozumab displays best results in treatment-naïve patients, its favourable effects on BMD were observed even in women previously treated with teriparatide or denosumab, although to a lesser extent. CONCLUSIONS: Based on the available evidence, romosozumab could be proposed as ideal drug in several clinical settings, such as non-fractured post-menopausal women at very-high risk of fractures, patients with recent hip fracture, patients non responder to bisphosphonates and short-term denosumab therapy.
RESUMEN
Currently available biotherapeutics for the treatment of osteoporosis lack explicit mechanisms for bone localization, potentially limiting efficacy and inducing off-target toxicities. While various strategies have been explored for targeting the bone surface, critical aspects remain poorly understood, including the optimal affinity ligand, the role of binding avidity and circulation time, and, most importantly, whether or not this strategy can enhance the functional activity of clinically relevant protein therapeutics. To investigate, we generated fluorescent proteins (eg, mCherry) with site-specifically attached small molecule (bisphosphonate) or peptide (deca-aspartate, D10) affinity ligands. While both affinity ligands successfully anchored fluorescent protein to the bone surface, quantitative radiotracing revealed only modest femoral and vertebral accumulation and suggested a need for enhanced circulation time. To achieve this, we fused mCherry to the Fc fragment of human IgG1 and attached D10 peptides to each C-terminus. The mCherry-Fc-D10 demonstrated an ~80-fold increase in plasma exposure and marked increases in femoral and vertebral accumulation (13.6% ± 1.4% and 11.4% ± 1.3% of the injected dose/g [%ID/g] at 24 h, respectively). To determine if bone surface targeting could enhance the efficacy of a clinically relevant therapeutic, we generated a bone-targeted sclerostin-neutralizing antibody, anti-sclerostin-D10. The targeted antibody demonstrated marked increases in bone accumulation and retention (20.9 ± 2.5% and 19.5 ± 2.5% ID/g in femur and vertebrae at 7 days) and enhanced effects in a murine model of ovariectomy-induced bone loss (bone volume/total volume, connectivity density, and structure model index all increased [P < .001] vs untargeted anti-sclerostin). Collectively, our results indicate the importance of both bone affinity and circulation time in achieving robust targeting of therapeutic proteins to the bone surface and suggest that this approach may enable lower doses and/or longer dosing intervals without reduction in biotherapeutic efficacy. Future studies will be needed to determine the translational potential of this strategy and its potential impact on off-site toxicities.
Several biologic therapies have been approved for osteoporosis, but they lack means of localization to bone tissue, potentially limiting their efficacy and leading to off-target toxicities. This manuscript investigates strategies for targeting biotherapeutics to the bone surface and asks the question of whether or not this approach can enhance functional activity and allow for lower or less frequent dosing. To define the key determinants of bone surface targeting, we begin by synthesizing fluorescent model proteins with different bone targeting tags. We show that even 1 tag is enough to make the surface of the femur and vertebrae fluorescent following systemic administration. The results are relatively modest at first, but when we combine the bone targeting tag with a second modification that makes the protein circulate in the body for a longer period of time, we observe a huge increase in bone surface delivery. We then synthesize a bone surface targeted version of a sclerostin-inhibiting antibody and show that it is more effective than the untargeted antibody and provides near complete protection of bone density despite relatively low dose. Our findings could have translational implications for existing bone therapies and help guide design of future strategies for optimized bone surface targeting.
Asunto(s)
Anticuerpos Neutralizantes , Animales , Humanos , Femenino , Anticuerpos Neutralizantes/farmacología , Ratones , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Huesos/metabolismo , Huesos/efectos de los fármacos , Proteínas Luminiscentes/metabolismo , Proteína Fluorescente Roja , Fémur/patología , Fémur/efectos de los fármacos , Fémur/metabolismo , Sistemas de Liberación de Medicamentos , Difosfonatos/farmacología , Péptidos y Proteínas de Señalización IntercelularRESUMEN
Two months after her first pregnancy, a 35-yr-old exclusively breastfeeding woman bent to move her baby in the car seat and experienced sudden, severe pain from 5 spontaneous vertebral compression fractures. Genomic screen was negative but she had mild ankylosing spondylitis previously well controlled on etanercept. She was vegetarian with a high phytate intake. A lactation consultant had advised her to pump and discard milk between feeds, leading her to believe she produced twice as much milk as her baby ingested. She presented with a LS Z score of -3.6 and a TH Z score of -1.6. After 6 mo postweaning, she was treated with teriparatide (14 mo intermittently over 18 mo) and ultimately achieved a 50% increase in LS bone density and an 8% increase in TH bone density. Her fragility is explained by normal lactational bone loss amplified by excessive milk production and phytate-induced impairment of intestinal calcium absorption, ankylosing spondylitis, and the bend-and-lift maneuver. The marked increase in bone density resulted from the combined effects of spontaneous recovery and pharmacotherapy. Spontaneous recovery of bone mass and strength should occur during 12 mo after weaning in all women, including those who have fractured.
Asunto(s)
Fracturas por Compresión , Osteoporosis , Fracturas de la Columna Vertebral , Espondilitis Anquilosante , Humanos , Embarazo , Femenino , Lactancia Materna , Ácido Fítico/farmacología , Ácido Fítico/uso terapéutico , Fracturas de la Columna Vertebral/tratamiento farmacológico , Osteoporosis/diagnóstico por imagen , Osteoporosis/tratamiento farmacológico , Lactancia , Densidad ÓseaRESUMEN
In this 16th edition of the annual banned-substance review on analytical approaches in human sports drug testing, literature on recent developments in this particular section of global anti-doping efforts that was published between October 2022 and September 2023 is summarized and discussed. Most recent additions to the continuously growing portfolio of doping control analytical approaches and investigations into analytical challenges in the context of adverse analytical findings are presented, taking into account existing as well as emerging challenges in anti-doping, with specific focus on substances and methods of doping recognized in the World Anti-Doping Agency's 2023 Prohibited List. As in previous years, focus is put particularly on new or enhanced analytical options in human doping controls, appreciating the exigence and core mission of anti-doping and, equally, the conflict arising from the opposingly trending extent of the athlete's exposome and the sensitivity of instruments nowadays commonly available in anti-doping laboratories.
Asunto(s)
Doping en los Deportes , Sustancias para Mejorar el Rendimiento , Deportes , Humanos , Doping en los Deportes/prevención & control , Detección de Abuso de Sustancias , LaboratoriosRESUMEN
Osteoporosis is a chronic condition characterized by decreased bone mass, loss of skeletal integrity, and increased susceptibility to fracture. Drugs used to treat osteoporosis can be classified as those that block bone resorption (antiresorptive), stimulate bone formation (anabolic), or do both. While all currently approved medications reduce the risk of fragility fractures in high-risk populations, they are generally unable to fully restore bone strength in most patients with established disease. Thus, the majority of patients require disease management over many years. Unfortunately, the continuous use of a single drug has limitations, both in terms of efficacy and safety, and so sequential therapy is commonly required. Given the expanding list of pharmacological agents currently available, careful consideration needs to be given as to which drugs to use and in what sequence. This review will evaluate the differential effects of antiresorptive, bone-forming, and dual-acting drugs when used in specific sequences and will explore the current evidence favoring the initial use of bone-forming/dual-acting drugs followed by antiresorptive medications. This review will also examine the notion that long-term treatment with an antiresorptive drug may diminish the efficacy of subsequent treatment with a bone-forming/dual-acting drug. Finally, this review will explore the current evidence pertaining to the specific issue of how to best prevent the clinical ramifications of denosumab cessation.
Asunto(s)
Conservadores de la Densidad Ósea , Fracturas Óseas , Osteoporosis Posmenopáusica , Osteoporosis , Femenino , Humanos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Densidad Ósea , Osteoporosis/tratamiento farmacológico , Fracturas Óseas/prevención & controlRESUMEN
BACKGROUND: Since the 1970s, there has been a quantitative and qualitative decline in sperm parameters. The main hypothesis to explain such a rapid evolution is the involvement of environmental and behavioral phenomena. METHODS: A bibliographic search limited to English and French literature in men published before 7/2023 was carried out on the links between fertility and pollution, xenobiotics, tobacco, narcotics, cannabis, alcohol, weight, sport, sedentary lifestyle, sleep and anabolics. RESULTS: Profound changes in lifestyle have occurred over the past 50 years: reduced sleep time, sedentary lifestyle, dietary changes, tobacco consumption, use of narcotics and anabolics. These changes have a proven impact on spermogram parameters, and should be corrected in an effort to optimize reproductive health. Other environmental parameters: pollution, exposure to heavy metals, exposure to xenobiotics, phthalates and pesticides will be more difficult to exclude from patients' daily lives, but deserve to be taken more into account. CONCLUSION: This review should help the urologist to assess and counsel patients in order to improve their reproductive health. These factors should be routinely investigated in infertile men.
Asunto(s)
Infertilidad Masculina , Semen , Humanos , Masculino , Infertilidad Masculina/inducido químicamente , Estilo de Vida , Espermatozoides , NarcóticosRESUMEN
Multiple myeloma (MM) is an incurable bone marrow cancer characterized by the development of osteolytic lesions due to the myeloma-induced increase in osteoclastogenesis and decrease in osteoblastic activity. The standard treatment of MM often involves proteasome inhibitors (PIs), which can also have a beneficial off-target bone anabolic effect. However, long-term treatment with PIs is unadvised due to their high side-effect burden and inconvenient route of administration. Ixazomib is a new-generation, oral PI that is generally well tolerated; however, its bone effect remains unknown. Here, we describe the 3-month results of a single-center phase II clinical trial investigating the effect of ixazomib treatment on bone formation and bone microstructure. Thirty patients with MM in stable disease not receiving antimyeloma treatment for ≥3 months and presenting ≥2 osteolytic lesions received monthly ixazomib treatment cycles. Serum and plasma samples were collected at baseline and monthly thereafter. Sodium 18 F-Fluoride positron emission tomography (NaF-PET) whole-body scans and trephine iliac crest bone biopsies were collected before and after three treatment cycles. The serum levels of bone remodeling biomarkers suggested an early ixazomib-induced decrease in bone resorption. NaF-PET scans indicated unchanged bone formation ratios; however, histological analyses of bone biopsies revealed a significant increase in bone volume per total volume after treatment. Further analyses of bone biopsies showed unchanged osteoclast number and COLL1A1High -expressing osteoblasts on bone surfaces. Next, we analyzed the superficial bone structural units (BSUs), which represent each recent microscopic bone remodeling event. Osteopontin staining revealed that following treatment, significantly more BSUs were enlarged (>200,000 µm2 ), and the distribution frequency of their shape was significantly different from baseline. Overall, our data suggest that ixazomib induces overflow remodeling-based bone formation by decreasing the level of bone resorption and promoting longer bone formation events, making it a potentially valuable candidate for future maintenance treatment. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
Asunto(s)
Resorción Ósea , Mieloma Múltiple , Humanos , Mieloma Múltiple/diagnóstico por imagen , Mieloma Múltiple/tratamiento farmacológico , Inhibidores de Proteasoma/farmacología , Inhibidores de Proteasoma/uso terapéutico , Compuestos de Boro/efectos adversos , Resorción Ósea/tratamiento farmacológicoRESUMEN
Osteoporotic-related fractures cause significant patient disability, leading to a growing burden on health care systems. Effective secondary fracture prevention can be delivered by fracture liaison services (FLSs), but these are not available in most countries. A major barrier is insufficient policy prioritization, helped by the lack of economic assessments using national data and providing estimates of patient outcomes alongside health care resource use and cost impacts. The aim of this study was to develop an economic model to estimate the benefits and budget impact of FLSs and support their wider international implementation. Five interconnected stages were undertaken: establishment of a generic patient pathway; model design; identification of model inputs; internal validation and output generation; and scenario analyses. A generic patient pathway including FLS activities was built to underpin the economic model. A state-based microsimulation model was developed to estimate the impact of FLSs compared with current practice for men and women aged 50 years or older with a fragility fracture. The model provides estimates for health outcomes (subsequent fractures avoided and quality-adjusted life years [QALYs]), resource use, and health and social care costs, including those necessary for FLSs to operate, over 5 years. The model was run for an exemplar country the size of the United Kingdom. FLSs were estimated to lead to a reduction of 13,149 subsequent fractures and a gain of 11,709 QALYs. Hospital-bed days would be reduced by 120,989 and surgeries by 6455, while 3556 person-years of institutional social care would be avoided. Expected costs per QALY gained placed FLSs as highly cost-effective at £8258 per QALY gained over the first 5 years. Ten different scenarios were modeled using different configurations of FLSs. Further work to develop country-specific models is underway to delivery crucial national level data to inform the prioritization of FLSs by policy makers. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
Asunto(s)
Fracturas Osteoporóticas , Masculino , Humanos , Femenino , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/prevención & control , Reino Unido , Análisis Costo-Beneficio , Huesos , Análisis de Costo-EfectividadRESUMEN
Although bone mineral density (BMD) is a predictor of fracture, many fractures occur in women with T-scores > -2.5. Bone microarchitecture, assessed by trabecular bone score (TBS), predicts fracture risk independent of BMD. We evaluated whether abaloparatide improves TBS and whether TBS trends were associated with vertebral fracture risk reduction. Women with osteoporosis randomized to abaloparatide or placebo for 18 months (ACTIVE), followed by alendronate for 24 months (ACTIVExtend), with evaluable TBS, were included in this post hoc analysis (N = 911). TBS was calculated from spine BMD scans using an algorithm adjusted for tissue thickness (TBSth ) at baseline, 6, 18, and 43 months. Mean increments in TBSth from baseline within and between treatment groups, proportion of women with TBSth increments above least significant change (LSC) and proportion with degraded TBSth (<1.027) were calculated. Risk estimates for vertebral fracture were compared using binary logistic regressions adjusted for baseline age and spine BMD. At baseline, 42% had degraded TBSth . Mean TBSth increased 4% after 18 months abaloparatide (p < 0.001) and was unchanged with placebo. After 2 subsequent years of alendronate, the total cumulative TBSth increase was 4.4% with abaloparatide/alendronate and 1.7% with placebo/alendronate (group difference, p < 0.001). At 43 months, the proportion of women with degraded TBSth had declined to 21% with abaloparatide/alendronate and 37% with placebo/alendronate (p < 0.05). An increase in TBSth ≥ LSC was observed in 50% of abaloparatide-treated women at 18 months and was associated with decreased odds (odds ratio [OR]; 95% confidence interval [CI]) of vertebral fracture (0.19; 95% CI, 0.04-0.80, 6 months; 0.30; 95% CI, 0.11-0.79, 43 months). In conclusion, abaloparatide increased TBSth rapidly and progressively over 18 months and increments were maintained over 2 years with alendronate. TBSth increase was associated with vertebral fracture risk reduction. Microarchitectural improvement may be one mechanism by which abaloparatide strengthens vertebral bone. © 2023 Radius Health, Inc and The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
Asunto(s)
Conservadores de la Densidad Ósea , Osteoporosis Posmenopáusica , Osteoporosis , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Femenino , Humanos , Alendronato/farmacología , Alendronato/uso terapéutico , Hueso Esponjoso/diagnóstico por imagen , Fracturas Osteoporóticas/tratamiento farmacológico , Fracturas de la Columna Vertebral/tratamiento farmacológico , Osteoporosis/tratamiento farmacológico , Densidad Ósea , Conservadores de la Densidad Ósea/farmacología , Conservadores de la Densidad Ósea/uso terapéutico , Vértebras Lumbares , Osteoporosis Posmenopáusica/tratamiento farmacológicoRESUMEN
Monogenic high bone mass (HBM) disorders are characterized by an increased amount of bone in general, or at specific sites in the skeleton. Here, we describe 59 HBM disorders with 50 known disease-causing genes from the literature, and we provide an overview of the signaling pathways and mechanisms involved in the pathogenesis of these disorders. Based on this, we classify the known HBM genes into HBM (sub)groups according to uniform Gene Ontology (GO) terminology. This classification system may aid in hypothesis generation, for both wet lab experimental design and clinical genetic screening strategies. We discuss how functional genomics can shape discovery of novel HBM genes and/or mechanisms in the future, through implementation of omics assessments in existing and future model systems. Finally, we address strategies to improve gene identification in unsolved HBM cases and highlight the importance for cross-laboratory collaborations encompassing multidisciplinary efforts to transfer knowledge generated at the bench to the clinic. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
Asunto(s)
Densidad Ósea , Huesos , Densidad Ósea/genéticaRESUMEN
The combination of denosumab and teriparatide is an effective treatment strategy in postmenopausal osteoporosis, though skeletal gains are promptly lost when these agents are discontinued. In the DATA-HD study, we reported that a single dose of zoledronic acid (ZOL) maintains the increases in areal spine and hip bone mineral density (BMD) achieved with this combination for at least 12 months. The capacity of ZOL to maintain corresponding improvements in peripheral volumetric BMD and microarchitecture, however, has not been reported. In the 15-month DATA-HD study, 76 postmenopausal osteoporotic women were randomized to receive 9 months of teriparatide (20-µg or 40-µg daily) overlapped with denosumab (60 mg at months 3 and 9). In the Extension study, 53 participants received a single dose of ZOL (5 mg intravenously) 24-35 weeks after the last denosumab dose. We measured volumetric BMD and microarchitecture at the distal radius and tibia using high-resolution peripheral quantitative computed tomography at months 27 and 42. Despite ZOL administration, total and cortical BMD gradually decreased over 27 months resulting in values similar to baseline at the radius but still significantly above baseline at the tibia. At both sites, cortical porosity decreased to values below pretreatment baseline at month 27 but then increased from month 27 to 42. There were no significant changes in trabecular parameters throughout the 27-month post-ZOL observation period. Stiffness and failure load, at both sites, decreased progressively from month 15 42 though remained above baseline at the tibia. These findings suggest that in contrast to the largely maintained gains in dual-energy X-ray absorptiometry (DXA)-derived spine and hip BMD, a single dose of ZOL was not as effective in maintaining the gains in volumetric peripheral bone density and microarchitecture produced by 15 months of overlapping treatment with denosumab and teriparatide. Alternative therapeutic approaches that can fully maintain improvements in peripheral bone parameters require further study. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
Asunto(s)
Conservadores de la Densidad Ósea , Osteoporosis Posmenopáusica , Femenino , Humanos , Teriparatido/uso terapéutico , Denosumab/farmacología , Denosumab/uso terapéutico , Ácido Zoledrónico/farmacología , Ácido Zoledrónico/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Densidad ÓseaRESUMEN
Dado el problema de salud pública que plantean los esteroides anabólicos, el consumo de ayudas ergogénicas está aumentando a nivel mundial, no es en Bolivia. Además, existe un consumo desmedido de suplementos nutricionales y farmacéuticos, así como efectos reversibles e irreversibles de los esteroides anabólicos. Objetivos: describir cómo se consumen las ayudas ergogénicas nutricionales y farmacéuticas y cómo los asistentes a gimnasios en el municipio Cercado de Cochabamba perciben sus efectos en su salud. Métodos: se realizó un estudio observacional transversal con 378 participantes mayores de 18 años, (estratificada) divididos en cuatro grupos; Amateur, Fitness, Deportista y en nueve gimnasios y dos grupos (NABBA-IFFB) y deportistas en general en el área metropolitana de Cercado Cochabamba. Resultados: se encontró que el 74,6% consume alguna sustancia que mejoran el rendimiento; el consumo de ayudas ergogénicas nutricionales fue del 57,1%(n=216) y farmacológicas el 17,4% (n=66). El tiempo dedicado a entrenamiento y dieta para el grupo amateur es estadísticamente significativo con un valor de (p<0,05). Los efectos percibidos y reportados por el consumo de ayudas ergogénicas farmacológicas (esteroides anabólicos androgénicos) son principalmente cambios de humor, alteración en la libido y acné. Entre los efectos secundarios irreversibles dos casos de hombres desarrollaron ginecomastia y dos mujeres desarrollaron clítoromegalia. Conclusiones: los usuarios de ejercicio en el gimnasio consumen grandes cantidades de sustancias nutricionales y/o farmacológica que mejoran el rendimiento.
Given the public health problem posed by anabolic steroids, the consumption of ergogenic aids is increasing worldwide, not indifferently in Bolivia. In addition, there is an excessive consumption of nutritional and pharmaceutical supplements, as well as reversible and irreversible effects of anabolic steroids. Objectives: to describe how nutritional and pharmaceutical ergogenic aids are consumed and how gym-goers in the Cercado municipality of Cochabamba perceive their effects on their health. Methods: a crosssectional observational study was conducted with 378 participants over 18 years of age, (stratified) divided into four groups; Amateur, Fitness, Athlete and in 9 gyms and 2 groups (NABBA-IFFB) and athletes in general in the metropolitan area of Cercado Cochabamba. Results: it was found that 74.6% consumed some performance-enhancing substance; the consumption of nutritional ergogenic aids was 57.1% (n=216) and pharmacological aids 17.4% (n=66). Time dedicated to training and diet for the amateur group is statistically significant with a value of (p<0.05). The perceived and reported effects of the consumption of pharmacological ergogenic aids (anabolic androgenic steroids) are mainly mood changes, libido alteration and acne. Among the irreversible side effects 2 cases of men developed gynecomastia and 2 women developed clitoromegaly. Conclusions: exercise users in the gym consume large amounts of nutritional and/or pharmacological performance enhancing substances.
RESUMEN
Teriparatide, recombinant parathyroid hormone (PTH[1-34]), and abaloparatide, an analogue of PTH related-peptide (PTHrP[1-34]), are both anabolic medications for osteoporosis that target the PTH receptor PTH1R. PTH1R is a G protein-coupled receptor, and the stimulatory Gs protein is an important mediator of the anabolic actions of PTH1R activation in bone. We have published that mice lacking the α subunit of Gs in osteoprogenitors do not increase bone mass in response to PTH(1-34). Unexpectedly, however, PTH(1-34) still increases osteoblast numbers and bone formation rate in male mice, suggesting that PTH1R may have both Gs-dependent and -independent actions in bone. Here we examine the role of Gs signaling in the anabolic actions of abaloparatide. We find that abaloparatide increases bone formation in male mice with postnatal deletion of Gsα in Osx-expressing osteoprogenitors (P-GsαOsxKO mice) but not in female P-GsαOsxKO mice. Therefore, abaloparatide has anabolic effects on bone in male but not female mice that appear to be independent of Gs-mediated signaling. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
RESUMEN
Bone nodule formation by differentiating osteoblasts is considered an in vitro model that mimics bone modeling. However, the details of osteoblast behavior and matrix production during bone nodule formation are poorly understood. Here, we present a spatiotemporal analysis system for evaluating osteoblast morphology and matrix production during bone modeling in vitro via two-photon microscopy. Using this system, a change in osteoblast morphology from cuboidal to flat was observed during the formation of mineralized nodules, and this change was quantified. Areas with high bone formation were densely populated with cuboidal osteoblasts, which were characterized by blebs, protruding structures on their cell membranes. Cuboidal osteoblasts with blebs were highly mobile, and osteoblast blebs exhibited a polar distribution. Furthermore, mimicking romosozumab treatment, when differentiated flattened osteoblasts were stimulated with BIO, a GSK3ß inhibitor, they were reactivated to acquire a cuboidal morphology with blebs on their membranes and produced more matrix than nonstimulated cells. Our analysis system is a powerful tool for evaluating the cell morphology and function of osteoblasts during bone modeling. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
RESUMEN
Anabolic agents, such as intermittent parathyroid hormone (PTH), exert their treatment efficacy through activation of two distinct bone formation processes, namely, remodeling-based bone formation (RBF, bone formation coupled with prior bone resorption) and modeling-based bone formation (MBF, bone formation without prior activation of bone resorption). However, if not followed by an antiresorptive agent, treatment benefit was quickly lost upon withdrawal from anabolic agents. By using in vivo micro-computed tomography imaging and multiplex cryohistology with sequential immunofluorescence staining, we investigated the temporal response of newly formed bone tissue from MBF and RBF and the preexisting bone tissue to withdrawal from PTH treatment and the associated cellular activity in an ovariectomized (OVX) rat model. We first demonstrated continued mineral apposition at both RBF and MBF sites following PTH discontinuation, resulting in an extended anabolic effect after 1-week withdrawal from PTH. It was further discovered that MBF sites had a greater contribution than RBF sites to the extended anabolic effect upon early withdrawal from PTH, evidenced by a higher percentage of alkaline phosphatase-positive (ALP+) surfaces and far greater bone formation activity at MBF versus RBF sites. Furthermore, significant bone loss occurred after 3 weeks of discontinuation from PTH, resulting from marked loss of newly formed bone tissue from RBF and preexisting bone tissue prior to treatment. In contrast, MBF surfaces had a delayed increase of tartrate-resistant acid phosphatase activity following PTH discontinuation. As a result, newly formed bone tissue from MBF had greater resistance to PTH discontinuation-induced bone loss than those from RBF and preexisting bone. Understanding various responses of two distinct bone formation types and preexisting bone to anabolic treatment discontinuation is critical to inform the design of follow-up treatment or cyclic treatment strategies to maximize treatment benefit of anabolic agents. © 2022 American Society for Bone and Mineral Research (ASBMR).