Special Issue: Metabolic Bone Diseases: Molecular Biology, Pathophysiology and Therapy.

Bone is a vital tissue as it carries out various metabolic functions: support of the body, protection of the internal organs, mineral deposit and hematopoietic functions [...].

Trabecular bone score and phalangeal quantitative ultrasound are associated with muscle strength and fracture risk in hemodialysis patients.

There is growing interest in the relationship between chronic kidney disease (CKD) and fragility fracture risk. Bone mineral density (BMD) is a major determinant of bone strength, although its role as a predictor of fracture in advanced CKD and hemodialysis is still under debate. We aimed to further investigate surrogates of bone quality and their associations with muscle strength and fracture risk in hemodialysis. Multiple clinical risk factors for fracture and an estimated 10-year probability of fracture, BMD at lumbar spine and femur, trabecular bone score (TBS), X-ray vertebral morphometry, phalangeal bone quantitative ultrasonography (QUS), tibial pulse-echo ultrasonography (PEUS), and handgrip strength were evaluated in a setting of hemodialysis patients in treatment with acetate-free biofiltration (AFB) or bicarbonate hemodialysis. The bone ultrasound measurements, both at phalangeal and tibial sites, were significantly associated with lumbar and femoral DXA values. Handgrip strength was significantly associated with the 10-year probability of fracture (r = -0.57, p < 0.001 for major fractures and r = -0.53, p < 0.001 for hip fracture, respectively), with femur neck, total femur, and L1-L4 BMD values (r = 0.47, p = 0.04; r = 0.48, p = 0.02; r = 0.58, p = 0.007, respectively), with TBS at the lumbar spine (r = 0.71, p < 0.001) and with the phalangeal QUS measure of AD-SoS (r = 0.369, p = 0.023). In the hemodialysis group, 10 participants (24.3%) reported at least one morphometric vertebral fracture (Vfx); conversely, only six participants (15%) showed Vfx in the control group. In the hemodialysis group, participants with Vfx compared with participants without Vfx reported significantly different TBS, bone transmission time (BTT), cortical thickness, and handgrip strength (p < 0.05). At multiple regression analysis, by identifying as dependent variable the 10-year fracture risk for major fracture, after correcting for age, BMI, time since dialysis, AD-SoS, cortical bone thickness, and handgrip strength, only BTT (ß = -15.21, SE = 5.91, p = 0.02) and TBS (ß = -54.69, SE = 21.88, p = 0.02) turned out as independently associated with fracture risk. In conclusion, hemodialysis patients showed a higher fracture risk and lower surrogate indices of bone strength as TBS and QUS parameters. In this cohort of patients, handgrip strength measurements appeared to be a useful instrument to identify high-fracture-risk subjects.

Therapeutic Options for the Management of Aromatase Inhibitor- Associated Bone Loss.

BACKGROUND: Breast cancer is the most commonly occurring cancer in women worldwide. Early breast cancer is a kind of invasive neoplasm that has not proliferated beyond the breast or the axillary lymph nodes. Current therapeutic strategies for breast cancer mainly include local therapies such as surgery or radiotherapy and systemic therapies like chemotherapy, endocrine, and targeted therapy. Nowadays, the adjuvant treatment for hormone receptor-positive early breast cancer in postmenopausal women remains the main effective systemic therapy which can improve disease- free survival and overall survival; it involves several endocrine treatment regimens, including Selective Estrogen Receptor Modulators (SERMs), Aromatase Inhibitors (AIs), or a combination of them. AIs have been shown to be more effective in preventing recurrence in postmenopausal women with early breast cancer when compared with tamoxifen, thus representing the standard of care for adjuvant endocrine therapy. Although AIs are usually well-tolerated, they can have some side effects. Apart from the appearance of arthralgias or myalgias and cardiovascular events, AI therapies, reducing already low endogenous postmenopausal estradiol levels, cause increased bone loss and increase fracture risk in postmenopausal women. OBJECTIVES: The objective of this review is to evaluate the therapeutic options in the management of Aromatase Inhibitor-Associated Bone Loss (AIBL). METHODS: We reviewed the current literature dealing with different therapeutic options in the treatment of AIBL. RESULTS: Clinical practice guidelines recommend a careful evaluation of skeletal health in all women with breast cancer before AI therapy initiation. Adequate calcium and vitamin D intake have also been suggested. Pharmacological attempts to minimize AI-related bone loss have focused on the use of antiresorptive agents, such as bisphosphonates and denosumab to protect bone integrity and reduce the risk of fractures. Furthermore, clinical trials have shown that by making the bone microenvironment less susceptible to breast cancer metastasis, these drugs are able to increase disease- free survival. CONCLUSIONS: AI, that are the pillar of the systemic treatment for patients with hormone receptorpositive breast cancer, are associated with different side effects, and in particular, osteoporosis and fractures. Both bisphosphonates and denosumab are able to prevent this negative effect.

Familiar osteopoikilosis: Case report with differential diagnosis and review of the literature.

Osteopoikilosis (OP) is a rare autosomal dominant sclerosing bone disease, caused by heterozygous mutations in the LEMD3 gene. It is characterised by numerous focal lamellar bone compact deposits in the spongiosa. In this case report, we describe a famliar case of OP and review the literature.

Paget's Disease of Bone and Cardiovascular Risk: A Pilot Study.

BACKGROUND: The association between Paget's disease of bone (PDB) and increased cardiovascular (CV) risk has been suggested, but the literature is conflicting. OBJECTIVE: Our study aimed to evaluate two markers of CV risk, namely, common carotid artery intimamedia thickness (cIMT) and the aortic pulse wave velocity (PWV) in patients with PDB. METHODS: We enrolled 12 patients with PDB and 58 control subjects, matched for age. The diagnosis of PDB was based on clinical, radiological and biochemical parameters. RESULTS: Patients with PDB showed higher PWV values than the controls, whereas cIMT was slightly but not significantly increased. CONCLUSION: These findings, although limited by the small study population, represent an original observation that deserves further study. The higher arterial stiffness in PDB could be related to the increased bone turnover or the high levels of oxidative stress that characterize this population.

Early vascular ageing biomarkers in osteoporotic outpatients: a pilot study.

Osteoporosis and atherosclerosis are significant public health problems that often coexist, especially in the elderly. Although some studies have reported an age-dependent relationship, others have suggested a causal relationship between osteoporosis and atherosclerosis. The aim of our study was to evaluate the cardiovascular risk in a population of patients with osteoporosis by measuring carotid intima-media thickness (cIMT) and carotid-femoral pulse wave velocity (cf-PWV). A total of 58 patients with osteoporosis and an equal number of healthy control subjects were enrolled. All subjects underwent (1) a bone densitometry examination using dual X-ray absorptiometry, (2) a vascular evaluation for the measurements of cIMT and cf-PWV and (3) a blood sample for the evaluation of lipids and phosphocalcic metabolism. Patients with osteoporosis had a significant increase in cIMT and cf-PWV. There was also a significant inverse correlation between the femoral neck BMD and cf-PWV values. In conclusion, osteoporotic outpatients have earlier vascular ageing, with an increase of arterial stiffness. These data support a possible association between osteoporosis and atherosclerosis independent of age.

Hematological Diseases and Osteoporosis.

Secondary osteoporosis is a common clinical problem faced by bone specialists, with a higher frequency in men than in women. One of several causes of secondary osteoporosis is hematological disease. There are numerous hematological diseases that can have a deleterious impact on bone health. In the literature, there is an abundance of evidence of bone involvement in patients affected by multiple myeloma, systemic mastocytosis, thalassemia, and hemophilia; some skeletal disorders are also reported in sickle cell disease. Recently, monoclonal gammopathy of undetermined significance appears to increase fracture risk, predominantly in male subjects. The pathogenetic mechanisms responsible for these bone loss effects have not yet been completely clarified. Many soluble factors, in particular cytokines that regulate bone metabolism, appear to play an important role. An integrated approach to these hematological diseases, with the help of a bone specialist, could reduce the bone fracture rate and improve the quality of life of these patients.

[Vascular dysfunction in Cardiorenal Syndrome type 4].

The Cardiorenal Syndrome type 4 (CRS-4) defines a pathological condition in which a primary chronic kidney disease (CKD) leads to a chronic impairment of cardiac function. The pathophysiology of CRS-4 and the role of arterial stiffness remain only in part understood. Several uremic toxins, such as uric acid, phosphates, advanced glycation end-products, asymmetric dimethylarginine, and endothelin-1, are also vascular toxins. Their effect on the arterial wall may be direct or mediated by chronic inflammation and oxidative stress. Uremic toxins lead to endothelial dysfunction, intima-media thickening and arterial stiffening. In patients with CRS-4, the increased aortic stiffness results in an increase of cardiac workload and left ventricular hypertrophy whereas the loss of elasticity results in decreased coronary artery perfusion pressure during diastole and increased risk of myocardial infarction. Since the reduction of arterial stiffness is associated with an increased survival in patients with CKD, the understanding of the mechanisms that lead to arterial stiffening in patients with CRS4 may be useful to select potential approaches to improve their outcome. In this review we aim at discussing current understanding of the pathways that link uremic toxins, arterial stiffening and impaired cardiac function in patients with CRS-4.

Anticoagulants and Osteoporosis.

Anticoagulant agents are widely used in the treatment of thromboembolic events and in stroke prevention. Data about their effects on bone tissue are in some cases limited or inconsistent (oral anti-vitamin K agents), and in others are sufficiently strong (heparins) to suggest caution in their use in subjects at risk of osteoporosis. This review analyses the effects of this group of drugs on bone metabolism, on bone mineral density, and on fragility fractures. A literature search strategy was developed by an experienced team of specialists by consulting the MEDLINE platform, including published papers and reviews updated to March 2019. Literature supports a detrimental effect of heparin on bone, with an increase in fracture rate. Low molecular weight heparins (LMWHs) seem to be safer than heparin. Although anti-vitamin K agents (VKAs) have a significant impact on bone metabolism, and in particular, on osteocalcin, data on bone mineral density (BMD) and fractures are contrasting. To date, the new direct oral anticoagulants (DOACs) are found to safe for bone health.

Oxidative Stress in Peripheral Arterial Disease (PAD) Mechanism and Biomarkers.

Hemodynamic dysfunction mainly characterizes pathophysiology of peripheral arterial disease (PAD) leading to chronic ischemia. Hemodynamic dysfunction is the origin of intermittent claudication (chronic PAD) or of critical limb ischemia (very severe PAD). Notably, it is well known that oxidative stress (OxS) plays a pathophysiological role in PAD. The higher production of reactive oxygen species (ROS) from OxS and reduced redox capability are two crucial players in initiating and progressing PAD. A number of biomarkers highlight OxS and monitor it in PAD. The present review summarizes data on OxS, on biomarkers available to mark OxS occurrence and to monitor on PAD progression, as well as to evaluate the effects treatments in PAD patients. In conclusion, by detailing OxS and its biomarkers, we hope to encourage more studies to focus on drugs which combat OxS and inflammation.

A strange case of dyspnoea.

Acquired neuralgic amyotrophy, described for the first time by Parsonage and Turner, is a rare idiopathic disease that may occur in otherwise normal healthy individuals. It typically begins with sudden, unilateral shoulder pain that may also involve the neck and/or arm. Less frequently, the disease involves nerves other than those of the brachial plexus, such as phrenic nerves, resulting in dyspnoea. The diagnosis is based on the clinical presentation and is generally supported by electroneurography/electromyography. We report the case of a 45-year-old white man who was referred to our clinic for acute dyspnoea preceded by severe neck and right shoulder pain. Corticosteroid therapy ameliorated the clinical picture, but without a complete recovery.

Pathogenesis of Thalassemia Major-associated Osteoporosis: A Review with Insights from Clinical Experience

Due to increasing life expectancy in thalassemia major (TM), osteoporosis is emerging as a significant problem. Its aetiology is multifactorial, culminating in increased bone resorption and impaired remodelling. Hypogonadism and marrow expansion seem to play an important role, but iron overload, deferoxamine toxicity, a defective growth hormone-insulin-like growth factor-1 axis and multiple endocrinopathies may represent additional causes of bone damage. Many of these patients, though under appropriate treatment programs, do not achieve normal peak bone mass. The receptor activator of nuclear factor kappa-ß (RANK)/RANK ligand/osteoprotegerin and the Wnt/ß-catenin systems work as major mediators of imbalanced bone turnover and bone loss. Additional genetic factors, such as collagen type 1 alpha 1 and vitamin D receptor gene polymorphisms, may exert some influence on the enhanced fracture risk observed in TM. To date, in spite of adequate hormone replacement, chelating therapy and acceptable haemoglobin levels, subjects with TM display impaired bone density and imbalanced bone turnover, thus the puzzle of the pathogenesis of TM-induced osteoporosis remains far from being solved.

Peripheral artery disease and osteoporosis: Not only age­related (Review).

Osteoporosis and atherosclerosis are two chronic degenerative diseases that share several biochemical pathways and risk factors. Previous studies have associated osteoporosis with carotid atherosclerosis, cardiovascular mortality and stroke, but data on the relationship with peripheral artery disease are few and conflicting. The OPG/RANK/RANKL system and Wnt/beta catenin signaling seem to be deeply involved in the pathogenesis of bone alterations and atherosclerotic processes also affect arteries of the lower extremities. Hypovitaminosis D could also play a role in the relationship of these two diseases. New and larger studies are necessary to shed light on this association and to design new drugs able to act in both these chronic degenerative diseases.

Sclerostin is a possible candidate marker of arterial stiffness: Results from a cohort study in Catania.

Osteoporosis and cardiovascular disease are worldwide public health issues. Recent evidence indicates a possible role of the canonical Wnt/ß-catenin signalling pathway as a common mediator between these two diseases. The aim of the present study was to investigate the relationship between serum concentrations of sclerostin and Dkk1, two extracellular inhibitors of Wnt/ß-catenin signalling, with carotid intima-media thickness (CIMT) and with arterial stiffness, evaluated by measuring the pulse wave velocity (PWV) in an ambulatory population of adults. To this aim, 67 subjects were recruited in the 'Atherosclerosis and osteoporosis: identification of common pathogenetic factors' investigation. Serum sclerostin levels correlated positively with CIMT (r=0.314, p=0.03) and inversely with the augmentation index, a marker of arterial stiffness (r=-0.286, p<0.05), whereas Dkk1 did not. Moreover, in a multivariate linear regression model, sclerostin [ß -0.1472; p=0.0023; standard error (SE)=0.04620] was an independent predictor of PWV in the study subjects. Our study shows that, following adjustment for confounders, sclerostin is an independent predictor of arterial stiffness in an ambulatory population, whereas Dkk1 is not.

Bone health assessment by quantitative ultrasound and dual-energy x-ray absorptiometry in postmenopausal women with breast cancer receiving aromatase inhibitors.

OBJECTIVE: Phalangeal quantitative ultrasound (QUS) measurements provide surrogate information on bone quality. The aim of the present study was to assess bone status by phalangeal QUS and by dual-energy x-ray absorptiometry (DXA), and to evaluate bone turnover in breast cancer (BC) women receiving aromatase inhibitors (AIs). METHODS: Sixty postmenopausal BC women and 42 matched controls were recruited (mean age 61.64 ±â€Š8.33 y). Amplitude-dependent speed of sound (AD-SoS), bone transmission time (BTT), Ultrasound Bone Profile Index, as QUS parameters, L1-L4 and femoral neck BMD by DXA were assessed at baseline and after 18 months; serum bone-specific alkaline phosphatase (BSAP) and C-telopeptide of type 1 collagen were measured at baseline, 9 and 18 months. RESULTS: FRAX (without BMD) derived 10-years probability of major fractures and hip fractures were significantly associated with AD-SoS (r = -0.381, P = < 0.001 and r = -0.370, P < 0.001, respectively), Ultrasound Bone Profile Index (r = -0.434, P ≤ 0.001 and r = -0.409, P = < 0.001, respectively), BTT (r = -0.309, P = 0.002 and r = -0.340, P = 0.001, respectively). The median percent changes of AD-SoS (-3.71 [-5.38 to 0.11] vs -0.7 [-4.15 to 0.83], P = 0.02 respectively), BTT (-8.4 [-14.91 to -3.53] vs -1 [-5.72 to 3.75], P < 0.001 respectively) were significantly different between AIs users and controls. The same trend was observed for DXA measurements. BSAP and C-telopeptide of type 1 collagen significantly changed in AIs users. AD-SoS was associated with change of BMD at lumbar spine (ß, 0.16; SE, 0.08; P = 0.04) and change of BSAP (ß, -0.04; SE, 0.02; P = 0.04). CONCLUSIONS: Phalangeal QUS appeared a useful tool to evaluate bone quality in BC women on AIs.

Role of genetic pattern on bone mineral density in thalassemic patients.

OBJECTIVES: To evaluate the role of genetic background in osteoporosis/osteopenia development in beta-Thalassemia Major patients. DESIGN AND METHODS: The influence of VDR (FokI, BsmI) as well as COLIA1 (Sp1) gene polymorphisms on BMD was investigated in 40 patients. RESULTS: Although the examined gene polymorphisms did not significantly affect BMD variations in our population, BsmI was found to display beneficial effects on patient response to alendronate therapy. CONCLUSION: Genetic factors retain a potential role for improvement of osteoporosis management in thalassemic patients.

Effect of long-term treatment with raloxifene on mammary density in postmenopausal women.

OBJECTIVE: To evaluate in a group of postmenopausal women the effects of long-term raloxifene treatment on breast density using a digitized analysis of mammograms and on insulinlike growth factor-1 (IGF-1), insulinlike growth factor binding protein-3 (IGFBP-3), and sex hormone-binding globulin (SHBG) plasma levels. DESIGN: Seventy healthy postmenopausal women with normal body weight were enrolled in this study and were divided into two groups based on their bone status, evaluated by dual-energy x-ray at the lumbar spine (L2-4). Fifty women (chronological age 52.4 +/- 4.1 y, menopausal age 42.1 +/- 3.9 y), in whom the L2-4 T score was less than -2.5 SD, were treated with raloxifene HCl 60 mg/day orally for 2 years. The other 20 women (chronological age 53.6 +/- 3.5 y, age at menopause 43.1 +/- 3.6 y), in whom the L2-4 T score ranged between -1 and -2.5 SD, were enrolled as controls. All 70 women received calcium (1 g/d orally) and cholecalciferol (880 UI/d orally) supplementation. Moreover, all women followed a normocaloric and personalized diet. All women had mammography at baseline and after 2 years of therapy. The mammographic images on traditional support (radiography) were acquired by using a film scanner and were then elaborated by means of ad hoc software. Moreover, assessments of IGF-1, IGFBP-3, and SHBG plasma levels were obtained at baseline and after 24 months. RESULTS: After 24 months of therapy, there was a significant variation in the raloxifene-treated group with respect to baseline in the distribution of gray classes of radiographic images. In particular, an attenuation of graphic trace with a reduction of the areas with the lowest and most elevated gray classes was observed. In the control group, no significant variations of graphic traces were observed. Moreover, raloxifene treatment significantly reduced IGF-1 and increased IGFBP-3 and SHBG plasma levels at 24 months. During follow-up, IGF-1, IGFPB-3, and SHBG levels did not change significantly in the control group. CONCLUSIONS: Long-term treatment with raloxifene in a population of postmenopausal women is able to reduce breast density. Such an effect could perhaps explain the reduction in the incidence of mammary carcinoma observed in the Multiple Outcomes of Raloxifene Evaluation study probably due to the direct antiestrogenic activity of raloxifene on mammalian tissue and/or its indirect activity increasing SHBG levels or modifying the IGF-1/IGFBP-3 ratio.