Low bone density and low serum levels of soluble RANK ligand are associated with severe arterial calcification in patients with Takayasu arteritis

Serum osteoprotegerin and its gene polymorphisms in patients with Takayasu's arteritis: a bicentric cross-sectional study

INTRODUCTION

Takayasu's arteritis (TAK) patients are at an elevated risk of metabolic syndrome and cardiovascular diseases (CVD). Currently, there are no well-validated biomarkers to assess this risk in this population. Previous research in different cohorts has linked serum levels of osteoprotegerin (OPG) and its polymorphisms to accelerated atherosclerosis and a marker of poor prognosis in CVD. Thus, we assessed this protein as a potential biomarker of CVD in TAK patients.

OBJECTIVES

To evaluate the serum levels of OPG and its SNPs (single nucleotide polymorphisms) in TAK patients and healthy controls, and to associate these parameters with clinical data.

METHODS

This bicentric cross-sectional study included TAK patients who were compared with healthy individuals (control group). The serum levels of OPG and the frequency of OPG SNPs [1181G > C (rs2073618), 245 A > C (rs3134069), 163T > C (rs3102735), and 209 C > T (rs3134070)] were compared between the both groups and associated with clinical data.

RESULTS

In total, 101 TAK patients and 93 controls were included in the study. The serum levels of OPG (3.8 ± 1.9 vs. 4.3 ± 1.8pmol/L, respectively; P = 0.059), and its four polymorphisms were comparable between both groups. In an additional analysis of only TAK patients, serum OPG levels and its four genes were not associated with any CVD parameters, except for higher OPG levels among patients without dyslipidemia.

CONCLUSION

No significant differences were observed in serum OPG levels or in the genotype frequencies of OPG SNPs between the patient and control groups. Similarly, no correlation was found between laboratory parameters and clinical data on CVD risk in TAK patients.

Serum biomarkers for arterial calcification in humans: A systematic review

Aim

To clarify the role of mediators of ectopic mineralization as biomarkers for arterial calcifications.

Methods

MEDLINE and Embase were searched for relevant literature, until January 4th 2022. The investigated biomarkers were: calcium, phosphate, parathyroid hormone, vitamin D, pyrophosphate, osteoprotegerin, receptor activator of nuclear factor-kappa B ligand (RANKL), fibroblast growth factor-23 (FGF-23), Klotho, osteopontin, osteocalcin, Matrix Gla protein (MGP) and its inactive forms and vitamin K. Studies solely performed in patients with kidney insufficiency or diabetes mellitus were excluded.

Results

After screening of 8985 articles, a total of 129 articles were included in this systematic review. For all biomarkers included in this review, the results were variable and more than half of the studies for each specific biomarker had a non-significant result. Also, the overall quality of the included studies was low, partly as a result of the mostly cross-sectional study designs. The largest body of evidence is available for phosphate, osteopontin and FGF-23, as a little over half of the studies showed a significant, positive association. Firm statements for these biomarkers cannot be drawn, as the number of studies was limited and hampered by residual confounding or had non-significant results. The associations of the other mediators of ectopic mineralization with arterial calcifications were not clear.

Conclusion

Associations between biomarkers of ectopic mineralization and arterial calcification are variable in the published literature. Future longitudinal studies differentiating medial and intimal calcification could add to the knowledge of biomarkers and mechanisms of arterial calcifications.

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We researched the association between biomarkers and arterial calcifications.

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This review focused on biomarkers of bone metabolism and Matrix Gla protein.

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Associations between biomarkers and arterial calcification are variable.

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Future studies should differentiate between medial and intimal calcifications.

Decreased level of soluble receptor activator of nuclear factor-κβ ligand (sRANKL) in overweight and obese children

INTRODUCTION

Childhood obesity contributes to the development of cardiovascular diseases. The molecular pathway - receptor activator of nuclear factor-κβ ligand (RANKL), its receptor RANK and osteoprotegerin (OPG) - takes part not only in bone metabolism but is also involved in the atherosclerosis process. RANKL stimulates osteogenic differentiation and calcification of vascular smooth cells. The associations between the OPG-sRANKL system and various cardiovascular risk factors were displayed. We aimed to evaluate the relationships between serum sRANKL (soluble RANKL) levels and the OPG/sRANKL ratio with cardiometabolic risk factors in overweight and obese children.

MATERIAL AND METHODS

The study included 70 children with overweight and obesity (mean age 13.0 ± 2.8) and 35 age-matched normal weight, healthy peers as a control group. In all patients, anthropometric measurements and laboratory tests were performed. Additionally, an oral glucose tolerance test (OGTT) was made only in overweight and obese children. Atherogenic and insulin resistance indices were calculated.

RESULTS

Overweight and obese children had lower sRANKL levels compared to the control group (median 276.95 vs 325.90, p=0.011), and consequently a higher OPG/sRANKL ratio (0.02 vs 0.01, p = 0.013). The studied children in the lowest quartile of sRANKL levels had higher body weight, Body Mass Index, waist circumference and increased glucose and insulin levels 60 minutes after OGTT and higher uric acid values compared to children in the highest quartile. In multivariable linear regression analysis sRANKL negatively correlated only with uric acid (β = - 0.508, p = 0.041). No association was found for the OPG/sRANKL ratio.

CONCLUSION

Excess fat mass seems to alter the OPG/RANKL ratio mainly by reducing serum sRANKL levels. The correlation between sRANKL and uric acid may suggest a contribution of the OPG-sRANKL system in the cardiometabolic process, but that observation should be confirmed in future studies.

Aortic Calcification in Takayasu Arteritis: Risk Factors and Relationship With Activity and Vascular Lesion. It Is Not Only an Aging Question

INTRODUCTION

Aortic calcification is a frequent finding in Takayasu arteritis (TA). The aim of this study was to evaluate the risk factors for aortic calcification in TA and its relationship with disease activity and the presence and type of vascular lesion.

METHODS

Nineteen patients with TA underwent nonenhanced computed tomography to measure the calcium score of the aorta and its main branches, which were divided into 13 segments. In each segment, the type of vascular lesion was evaluated by noninvasive angiography. Clinical risk factors and disease activity scores were recorded.

RESULTS

Eighteen of 19 patients (95%) were women, with a median age of 25 years. Median of calcium score was 69 AU (0-12,465 AU). Eleven of 19 patients (57.9%) had calcium score greater than 0. Age, evolution time, and dyslipidemia were higher in patients with calcium, whereas the National Institutes Health and Dabague disease activity scores were lower. There was no association between the presence of calcium and vascular lesion: 60 of 160 segments (37.5%) without calcium had some lesion, compared with 24 of 68 (35.3%) with calcium score greater than 0, p = 0.75. However, occlusion was more frequent in patients with calcium, whereas wall thickening was in those without calcium.

CONCLUSIONS

Aortic calcification in TA is related to age, evolution time, and abnormalities in lipid profile and occlusion and, inversely with some activity scores. Identification of calcification could be useful in identifying patients that even without significant lesions might have accelerated atherosclerosis, and who might be benefited with specific treatment.

Does the OPG/RANKL system contribute to the bone-vascular axis in chronic kidney disease? A systematic review

Vascular calcification (VC) is highly prevalent in patients with chronic kidney disease (CKD) and is strongly associated with cardiovascular mortality and morbidity. Accumulating evidence over the past decade has challenged the hypothesis of close interaction between bone and VC what raises the possibility of a common underlying pathophysiological mechanism. Lately, bone regulatory proteins such as: osteoprotegerin (OPG) and Receptor Activator for Nuclear Factor κB Ligand (RANKL) has attracted attention of researchers as a possible key mediators of bone-vascular calcification imbalance. The literature search was carried out using the MEDLINE/PubMed database and a combination of keywords and MeSH terms, and only papers published since January 2005 to July 2016 were selected. The search resulted in 562 potential articles. After selection according to the eligibility criteria, 107 studies fulfilled were included (102 full texts and 5 was case reports). OPG and RANKL plays essential role in the regulation of bone metabolism and may be regarded as a possible link between VC, bone and mineral metabolism in CKD patients. Further studies are required to determine the diagnostic significance of these proteins in evaluation of progression and severity of VC process in CKD patients. Finally, the efficacy and safety, especially in regard to VC, of anti-RANKL therapy in CKD patients requires well-designed prospective, randomized trials.

Vascular surgery: the main risk factor for mortality in 146 Takayasu arteritis patients

Takayasu arteritis (TA) is an idiopathic chronic inflammatory disease that affects the aorta and its main branches. According to disease involvement, patients may require surgical treatment mainly due ischemic lesions in association with medical therapy. We evaluated the impact of vascular interventions in a cohort of TA patients. Medical records from 146 TA patients were reviewed. Clinical features, medical, and surgical treatment were revised and disease activity was determined by clinical, laboratorial, and imaging parameters. Clinical parameters associated with mortality alongside vascular procedures were evaluated and their impact on mortality in our cohort was estimated. Ninety-four vascular interventions were performed in 61 patients (41.8%). A third of them were of endovascular procedures. The overall mortality was 4.1%, all due to early postoperative complications, which resulted in a rate of surgery-related mortality of 9.8%. All deaths occurred in patients with active disease. Clinical parameters known to be associated with mortality (aneurysm, secondary hypertension, aortic insufficiency, and cerebrovascular accident) were not found related with death. Patients whose disease began before age 20 years had an OR 3.54 of undergoing a vascular surgical intervention. The observed impact of vascular procedures on mortality in patients with Takayasu arteritis, especially during disease activity, supports the notion that such interventions should be performed with caution and preferably during periods of remission.

Abnormal molecular response to Takayasu arteritis causing extensive large-vessel calcification

Takayasu arteritis is a large-vessel vasculitis that often results in pulselessness due to fibrotic stenoses. Whereas minor calcification is sometimes seen with Takayasu arteritis, it rarely causes stenosis. Extensive calcification resulting in malperfusion is exceedingly rare and has been attributed to disorders in calcium trafficking in a chronic inflammatory state. We report an unusual case of rapidly progressive and extensive aortic calcification in the setting of Takayasu arteritis.

Determinants of Arterial Stiffness in Female Patients with Takayasu Arteritis

Objective.

The assessment of pulse wave velocity (PWV) in Takayasu arteritis (TA) is complex because of many confounding factors. We evaluated PWV in female patients with TA and controls with comparable anthropometric and clinical variables and assessed a possible association of TA with disease variables.

Methods.

We evaluated 27 patients with TA consecutively. Exclusion criteria were menopause, smoking, diabetes, renal insufficiency, poorly controlled hypertension, cardiac arrhythmias, obesity, inflammatory comorbidities, pregnancy, and surgical procedures involving the aorta. Disease activity was determined by clinical and laboratory variables. As healthy controls, 27 subjects with comparable age, blood pressure, height, and weight were selected. Carotid-femoral PWV measurements were obtained using the Complior system.

Results.

The mean PWV in patients with TA was higher than in healthy controls (9.77 ± 3.49 vs 7.83 ± 1.06 m/s; p = 0.009). Despite our strict selection criteria, patients with TA had an average systolic blood pressure (SBP) 8 mmHg higher than controls (p = NS), and significantly higher pulse pressure values. The multivariate linear regression model shows that 93.8% of the PWV variability is explained by the variables age, mean BP, and the disease itself (adjusted R2= 0.938). Stepwise logistic analysis using the PWV cutoff value established by the receiver-operator characteristic curve (> 8.34 m/s) as dependent variable, and measures with significance in univariate analysis as independent variables revealed that TA (OR 4.69; 95% CI 1.31–16.72; p = 0.017) and mean BP (OR 1.06; 95% CI 1.00–1.12; p = 0.048) were independently associated with higher PWV. Further analysis of disease variables revealed that PWV values were not correlated with erythrocyte sedimentation rate, C-reactive protein, cumulative dose of glucocorticoid, or ejection fraction (p > 0.05).

Conclusion.

In our cohort of female patients with TA, the disease itself and mean BP were the strongest determinants associated with arterial stiffness.

Large vessel calcification in Takayasu arteritis

We report the novel case of a young woman with Takayasu arteritis, with extensive large vessel disease. The case demonstrates that while mechanisms of vascular calcification are poorly understood, inflammation per se might be sufficient to mediate increased mineral stress leading to vessel calcification, even in the absence of renal impairment.

High prevalence of metabolic syndrome in Takayasu arteritis: increased cardiovascular risk and lower adiponectin serum levels

OBJECTIVE

The prevalence of metabolic syndrome (MetS) tends to be high among rheumatic patients, and cardiovascular disease is the leading cause of death in these conditions. We aimed to determine the prevalence of MetS in patients with Takayasu arteritis (TA) and its association with risk factors and adipokine and cytokine levels.

METHODS

A cross-sectional study was conducted in 45 consecutive women with TA and 47 healthy controls matched by age and body mass index.

RESULTS

The prevalence of MetS (International Diabetes Federation/American Heart Association criteria) was higher in TA compared to controls (33.34 vs 8.51%, p = 0.003). Patients with TA had a higher frequency of hypertension (p < 0.001) and dyslipidemia (p = 0.001) and higher levels of insulin (p = 0.021), homeostasis model assessment index (p = 0.024), apolipoprotein E (p = 0.029), resistin (p = 0.018), and C-reactive protein (CRP, p < 0.001) compared to healthy subjects, with similar levels of adiponectin and plasminogen activator inhibitor-1 (PAI-1; p > 0.05). Further analysis of patients with TA with and without MetS revealed a higher frequency of overweight/obesity (66.66 vs 26.66%, p = 0.022), higher Framingham score ≥ 1 (p = 0.032), and lower adiponectin levels (20.37 ± 21.16 vs 38.64 ± 22.62 μg/ml, p = 0.022) in the patients with MetS. No differences were found regarding disease duration, activity, glucocorticoid use, resistin, and PAI-1 levels in the 2 groups of patients with TA (p > 0.05). Patients with and without MetS showed no differences in cytokine levels [interleukin 12 (IL-12, IL-1a, IL-6) and tumor necrosis factor-α]. IL-6 had a positive Pearson correlation with CRP only in TA patients with MetS (r = 0.57; p = 0.050).

CONCLUSION

A high prevalence of MetS was observed in patients with TA and this comorbidity seems to identify a subgroup of overweight/obese patients with high cardiovascular risk without a significant association with disease status. Further longitudinal studies are necessary to observe the effects of controlling this modifiable risk factor in the quality of life and survival of patients with TA.

Development of outcome measures for large-vessel vasculitis for use in clinical trials: opportunities, challenges, and research agenda

Giant cell (GCA) and Takayasu's arteritis (TAK) are 2 forms of large-vessel vasculitis (LVV) that involve the aorta and its major branches. GCA has a predilection for the cranial branches, while TAK tends to affect the extracranial branches. Both disorders may also cause nonspecific constitutional symptoms. Although some clinical features are more common in one or the other disorder and the ages of initial presentation differ substantially, there is enough clinical and histopathologic overlap between these disorders that some investigators suggest GCA and TAK may be 2 processes within the spectrum of a single disease. There have been few randomized therapeutic trials completed in GCA, and none in TAK. The lack of therapeutic trials in LVV is only partially explained by the rarity of these diseases. It is likely that the lack of well validated outcome measures for LVV and uncertainties regarding trial design contribute to the paucity of trials for these diseases. An initiative to develop a core set of outcome measures for use in clinical trials of LVV was launched by the international OMERACT Vasculitis Working Group in 2009 and subsequently endorsed by the OMERACT community at the OMERACT 10 meeting. Aims of this initiative include: (1) to review the literature and existing data related to outcome assessments in LVV; (2) to obtain the opinion of experts and patients on disease content; and (3) to formulate a research agenda to facilitate a more data-based approach to outcomes development.

Premature coronary artery calcification is associated with disease duration and bone mineral density in young female systemic lupus erythematosus patients

Our objective was to evaluate the relevance of traditional and disease-related cardiovascular risk factors and of bone mineral density for premature coronary artery calcification in young patients with systemic lupus erythematosus. Ninety-four female patients with systemic lupus erythematosus with disease durations >5 years and <45 years were consecutively selected. Cardiovascular risks (diabetes mellitus, arterial hypertension, dyslipoproteinemia, smoking, family history, body mass index, ovarian and renal insufficiency) and systemic lupus erythematosus-related risk factors (disease duration, ACR criteria, modified SLICC/ ACR, SLEDAI and treatment) were evaluated. Bone mineral density was assessed by dual X-ray absorptiometry. Coronary artery calcification was determined by computed tomography. Coronary artery calcification was identified in 12 (12.7%) patients and was associated with a higher frequency of patients with cardiovascular risks (p = 0.001), higher number of cardiovascular risks (p = 0.002), age (p = 0.025), disease duration (p = 0.011) and SLICC (p=0.011). Individual analysis of cardiovascular risks demonstrated that menopause (p = 0.036), dyslipidemia (p = 0.003) and hypertension (p = 0.006) were significantly associated with coronary artery calcification. In addition, coronary artery calcification was associated with a lower whole body bone mineral density (p = 0.013). Multiple logistic regression analysis using cardiovascular risks, age, disease duration, SLICC and whole body bone mineral density revealed that only disease duration (p = 0.038) and whole body bone mineral density (p = 0.021) remained significant for coronary artery calcification. In conclusion, we found that disease duration and decreased bone mineral density are independent predictors for premature coronary calcification in young women with systemic lupus erythematosus, suggesting a common underlying mechanism. Lupus (2010) 19, 27—33.

Osteoprotegerin/RANKL system imbalance in active polyarticular-onset juvenile idiopathic arthritis: a bone damage biomarker?

OBJECTIVE

To evaluate the importance of receptor activator of nuclear factor kappaB (RANK)/receptor activator of nuclear factor kappaB ligand (RANKL)/osteoprotegerin (OPG) modulation in active polyarticular juvenile idiopathic arthritis (pJIA) patients with and without bone erosions.

METHODS

Thirty female patients (mean age 11.07+/-3.77 years, range 4-17 years) with active pJIA and 30 healthy gender- and age-matched controls were consecutively selected for this study. All involved articulations were assessed by X-ray and examined for the presence of bone erosions. The serum levels of RANKL and OPG were measured using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

Patients with active pJIA had higher levels of serum RANKL than controls [2.90 (0.1-37.4) vs. 0.25 (0.1-5.7) pg/mL, p = 0.007] and a lower OPG/RANKL ratio [21.25 (1.8-897.6) vs. 347.5 (9-947.8), p = 0.005]. However, levels of OPG were comparable in both groups [55.24 (28.34-89.76) vs. 64.42 (30.68-111.28) pg/mL, p = 0.255]. Higher levels of serum RANKL and a lower OPG/RANKL ratio were also observed in active pJIA patients with bone erosions compared to controls [3.49 (0.1-37.4) vs. 0.25 (0.1-5.7) pg/mL, p = 0.0115 and 14.3 (1.8-897.6) vs. 347.5 (9-947.8), p = 0.016]. However, RANKL levels and OPG/RANKL ratio were similar in pJIA patients without bone erosion and controls [1.75 (0.1-10.9) vs. 0.25 (0.1-5.7) pg/mL, p = 0.055 and 29.2 (3.3-756.8) vs. 347.5 (9-947.8), p = 0.281].

CONCLUSION

These data suggest that active pJIA with bone erosions is associated with high serum levels of RANKL and a low OPG/RANKL ratio, indicating that these alterations may reflect bone damage in this disease.

Bone mineral apparent density in juvenile dermatomyositis: the role of lean body mass and glucocorticoid use

OBJECTIVE

To analyse bone mineral density (BMD) in juvenile dermatomyositis (JDM) and its possible association with body composition, disease activity, duration of disease, glucocorticoid (GC) use, and biochemical bone parameters, including osteoprotegerin (OPG) and receptor activator of nuclear factor kappaB (RANKL).

METHODS

Twenty girls with JDM and 20 controls matched for gender and age were selected. Body composition and BMD were analysed by dual-energy X-ray absorptiometry (DXA) and bone mineral apparent density (BMAD) was calculated. Duration of disease, cumulative GC, and GC pulse therapy use were determined from medical records. Disease activity and muscle strength were measured by the Disease Activity Score (DAS), the Childhood Myositis Assessment Scale (CMAS), and the Manual Muscle Test (MMT). Inflammatory and bone metabolism parameters were also analysed. OPG and RANKL were measured in patients and controls using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

A lower BMAD in the femoral neck (p<0.001), total femur (p<0.001), and whole body (p = 0.005) was observed in JDM patients compared to controls. Body composition analysis showed a lower lean mass in JDM compared to controls (p = 0.015), but no difference was observed with regard to fat mass. A trend of lower serum calcium was observed in JDM (p = 0.05), whereas all other parameters analysed, including OPG and RANKL, were similar. Multiple linear regression analysis revealed that, in JDM, lean mass (p<0.01) and GC pulse therapy use (p<0.05) were independent factors for BMAD in the hip region.

CONCLUSIONS

This study has identified low lean mass and GC pulse therapy use as the major factors for low hip BMAD in JDM patients.

Bone metabolism and vascular calcification

Osteoporosis and atherosclerosis are chronic degenerative diseases which have been considered to be independent and whose common characteristic is increasing incidence with age. At present, growing evidence indicates the existence of a correlation between cardiovascular disease and osteoporosis, irrespective of age. The morbidity and mortality of osteoporosis is mainly related to the occurrence of fractures. Atherosclerosis shows a high rate of morbidity and especially mortality because of its clinical repercussions such as angina pectoris, acute myocardial infarction, stroke, and peripheral vascular insufficiency. Atherosclerotic disease is characterized by the accumulation of lipid material in the arterial wall resulting from autoimmune and inflammatory mechanisms. More than 90% of these fatty plaques undergo calcification. The correlation between osteoporosis and atherosclerosis is being established by studies of the underlying physiopathological mechanisms, which seem to coincide in many biochemical pathways, and of the risk factors for vascular disease, which have also been associated with a higher incidence of low-bone mineral density. In addition, there is evidence indicating an action of antiresorptive drugs on the reduction of cardiovascular risks and the effect of statins, antihypertensives and insulin on bone mass increase. The mechanism of arterial calcification resembles the process of osteogenesis, involving various cells, proteins and cytokines that lead to tissue mineralization. The authors review the factors responsible for atherosclerotic disease that correlate with low-bone mineral density.

Pathogenesis of calciphylaxis: Hans Selye to nuclear factor kappa-B

The clinical syndrome of calciphylaxis is characterized by arteriolar medial calcification, thrombotic cutaneous ischemia, necrotic skin ulceration, and a high mortality rate. This review integrates calciphylaxis risk factors with the molecular processes governing osseous and extraosseous mineralization. As the pathogenesis of calciphylaxis is better understood, targeted therapies aimed at disease prevention and reversal will follow.