Advanced Calcification Research Articles

Relationship Between Calcified Plaque Burden, Vascular Inflammation, and Plaque Vulnerability in Patients With Coronary Atherosclerosis

BackgroundCoronary artery calcification is an integral part of atherosclerosis. It has been suggested that early coronary artery calcification is associated with active inflammation, and advanced calcification forms as inflammation subsides. Inflammation is also an important factor in plaque vulnerability. However, the relationship between coronary artery calcium burden, vascular inflammation, and plaque vulnerability has not been fully investigated. ObjectivesThis study aimed to correlate calcified plaque burden (CPB) at the culprit lesion with vascular inflammation and plaque vulnerability. MethodsPatients with coronary artery disease who had both computed tomography angiography and optical coherence tomography were included. The authors divided the patients into 4 groups: 1 group without calcification at the culprit lesion; and 3 groups based on the CPB tertiles. CPB was calculated as calcified plaque volume divided by vessel volume in the culprit lesion. The authors compared pericoronary adipose tissue (PCAT) attenuation for vascular inflammation and optical coherence tomography–derived vulnerable features among the 4 groups. ResultsAmong 578 patients, the highest CPB tertile showed significantly lower PCAT attenuation of culprit vessel compared with the other groups. The prevalence of features of plaque vulnerability (including lipid-rich plaque, macrophage, and microvessel) was also lowest in the highest CPB tertile. In the patients with calcification, higher age, statin use, and lower PCAT attenuation were independently associated with CPB. ConclusionsGreater calcium burden is associated with a lower level of vascular inflammation and plaque vulnerability. A greater calcium burden may represent advanced stable plaque without significant inflammatory activity. (Massachusetts General Hospital and Tsuchiura Kyodo General Hospital Coronary Imaging Collaboration; NCT04523194)

Novel ex-vivo calcification model for human aortic valves reveals patient-specific effect of compound

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Dekker grant Background Aortic stenosis (AS) is a narrowing of the aortic valve opening due to calcification and valve thickening. There are currently no pharmacological treatments for AS, and surgical interventions are the only therapies. To understand the molecular mechanisms underlying AS and test new pharmacological agents, advanced calcification models are required. These models need to closely approach native tissue response to stimuli by maintaining the valvular interstitial cells within their native environment. We have recently developed an ex vivo culture model that fulfills this requirement and allows the induction of calcification in slices of human aortic valves. Purpose Our goal is to evaluate the applicability of our ex-vivo calcification model as a pre-clinical test system for potential therapies. Methods Diseased aortic valves were dissected, embedded in agarose, then cut into 300-500 um slices using a vibratome. The use of multiple slices from a single patient ensured proper internal controls. To induce calcification, slices were cultured with 3mM phosphate(n=12), and control slices without phosphate (n=11). To investigate molecular modulation of induced calcification, dexamethasone was added to phosphate cultures(n=9). The slices were assessed for calcification using Alizarin Red staining. ImageJ was used to quantify the percentage of alizarin red-positive area. The average thickness was determined using 3DHISTECH software. Results In the presence of phosphate, a significant increase in the calcification percentage was observed in cultured valve slices compared with cultures without phosphate (p<0.05). Interestingly, within the phosphate-treated group, two sub-groups could be distinguished, one sub-group exhibiting extensive calcification, while the other showed virtually no sign of calcification. Paired comparisons revealed strong effect of dexamethasone depending on the extent of calcification-inducing capability of phosphate in each patient-sample. More precisely, dexamethasone exhibited potent inhibitory effect on calcification in valvular slices from patients where calcification was stimulated in the presence of phosphate. Conversely, dexamethasone exhibited a stimulatory effect on calcification in slices that did not show a stimulation of calcification in the presence of phosphate. This differential effect was strongly correlated with valve thickness.(r=-0.884,p< 0.01). Conclusions Our novel ex-vivo calcification model for human aortic valves revealed potential presence of patient-specific effects of pharmacological agents. Dexamethasone can have both stimulatory and inhibitory effects on calcification levels, influenced by phosphate response and valve thickness. As thickness might be indicative of the disease stage, this correlation suggests that the direction of compound’s effect might depend on disease stage. Hence, proper understanding of potential opposite effects of compounds is crucial in developing novel therapies.

The association of lipoprotein(a) and coronary artery calcium in asymptomatic patients: a systematic review and meta-analysis.

Lipoprotein(a) [Lp(a)] is an atherogenic lipid particle associated with increased risk for coronary heart disease (CHD) events. Coronary artery calcium (CAC) score is a tool to diagnose subclinical atherosclerosis and guide clinical decision-making for primary prevention of CHD. Studies show conflicting results concerning the relationship between Lp(a) and CAC in asymptomatic populations. We conducted a meta-analysis to evaluate the association of Lp(a) and CAC in asymptomatic patients. We systematically searched PubMed, Embase, and Cochrane until April 2023 for studies evaluating the association between Lp(a) and CAC in asymptomatic patients. We evaluated CAC > 0 Agatston units, and CAC ≥ 100. Lp(a) was analysed as a continuous or dichotomous variable. We assessed the association between Lp(a) and CAC with pooled odds ratios (OR) adopting a random-effects model. A total of 23 105 patients from 18 studies were included in the meta-analysis with a mean age of 55.9 years, 46.4% female. Elevated Lp(a) increased the odds of CAC > 0 [OR 1.31; 95% confidence intervals (CI) 1.05-1.64; P = 0.02], CAC ≥100 (OR 1.29; 95% CI 1.01-1.65; P = 0.04; ), and CAC progression (OR 1.43; 95% CI 1.20-1.70; P < 0.01; ). For each increment of 1 mg/dL in Lp(a) there was a 1% in the odds of CAC > 0 (OR 1.01; 95% CI 1.01-1.01; P < 0.01). Our findings of this meta-analysis suggest that Lp(a) is positively associated with a higher likelihood of CAC. Higher Lp(a) levels increased the odds of CAC >0. These data support the concept that Lp(a) is atherogenic, although with high heterogeneity and a low level of certainty. CRD42023422034. Asymptomatic patients with elevated Lp(a) had 31% higher chances of having any coronary calcification (CAC > 0) and 29% higher chances of having more advanced calcification (CAC > 100). It increased the chances of having progression of coronary calcification over time by 43%. For each 1 mg/dL of Lp(a) there was an increment of 1% chance of having coronary calcification.

Impact of Multi-Grade Localized Calcifications on Aortic Valve Dynamics under Helical Inflow: A Comparative Hemodynamic Study

This study investigates the hemodynamic impacts of localized aortic valve calcification, utilizing immersed boundary-finite element (IBFE) method simulations with realistic inflow patterns of uniform and helical blood flow from the left ventricular outflow tract (LVOT). We modeled the aortic valve leaflets with varying grades of calcification, assessing their influence on valve performance, including transvalvular hemodynamics, wall shear stress (WSS) indices, and vortical structures. The findings highlighted that calcification significantly restricts leaflet motion, diminishes the orifice area, disrupts flow efficiency, and consequently increases the left ventricular workload. Advanced calcification resulted in elevated WSS, especially at the leaflet tips, which indicates a heightened risk of endothelial damage and further calcification. Asymmetrical calcifications redirect flow towards the ascending aorta wall, potentially inducing structural damage and increased stress on the remaining healthy leaflets. Calcification was also found to alter the naturally occurring helical blood flow patterns, affecting the system’s fluid transport efficiency and possibly contributing to cardiovascular disease progression. The study revealed a significant alteration in vortex formation, with calcification causing distorted and complex vortex structures, which may influence the dynamics of blood flow and valve function. These insights into the hemodynamic changes induced by calcification contribute to a better understanding of the progression of aortic valve diseases and could inform more effective diagnostic and treatment strategies.

Echocardiographic Progression of Calcific Aortic Valve Disease in Patients with Preexisting Aortic Valve Sclerosis.

We aimed to evaluate echocardiographic parameters to predict calcific aortic valve disease (CAVD) progression. CAVD ranges from aortic valve sclerosis (ASc) with no functional impairment of the aortic valve to severe aortic stenosis (AS). It remains uncertain, which patients with ASc have a particularly high risk of developing AS. We included a total of 153 patients with visual signs of ASc and peak flow velocity (Vmax) below 2.5 m/s at baseline echocardiography. Progression of CAVD to AS was defined as an increase in Vmax 2.5 m/s with a delta of 0.1 m/s; stable ASc was defined as Vmax below 2.5 m/s and a delta 0.1 m/s. Finally, we compared clinical and echocardiographic parameters between these two groups. The mean age at baseline was 73.5 ( 8.2) years and 66.7% were of male sex. After a mean follow-up of 1463 days, 57 patients developed AS, while 96 patients remained in the ASc group. The AS group showed significantly more calcification (p 0.001) and thickening (p 0.001) of the aortic valve cusps at baseline, although hemodynamics showed no evidence of AS in both groups (ASc group: Vmax 1.6 0.3 m/s versus AS group: Vmax 1.9 0.3 m/s; p 0.001). Advanced calcification (odds ratio [OR]: 4.8, 95% confidence interval [CI]: 1.5-15.9; p = 0.009) and a cusp thickness 0.26 cm (OR: 16.6, 95% CI: 5.4-50.7; p 0.001) were independent predictors for the development of AS. The acquisition of simple echocardiographic parameter may help to identify patients with particularly high risk of developing AS.

Investigation of the effects of abdominal aortic calcification on mortality in spinal surgery

Objective: The aim of this study was to show the effect of the presence of AAC on mortality after lumbar degenerative disc surgery and to determine whether it is a predictor of survival.&#x0D; Methods: Between 2014 and 2016, abdominal aortic calcifications were recorded by grade in patients who underwent surgery for degenerative lumbar disc herniation and therefore underwent updated lumbar CT. In addition to the demographic data of these patients, ASA scores were also recorded and these scores were statistically compared.&#x0D; Results: The age of the patients in the Advanced Calcification group was significantly (p &lt; 0.05) higher than that in the Mild Calcification group. The ASA score in the Advanced Calcification group was significantly (p &lt; 0.05) higher than the Mild Calcification group. . Ex rate in the Advanced Calcification group was significantly (p &lt; 0.05) higher than the Mild Calcification group.&#x0D; Conclusion: There is a strong correlation between the degree of abdominal aortic calcifications and patient survival. This relationship is thought to be an important guiding scoring for spinal surgeons in the preoperative preparation phase.

Tratamiento quirúrgico de la insuficiencia mitral reumática

In rheumatic disease with mitral involvement, regurgitation is the most common form of presentation in young people. The possibility of surgical repair in rheumatic regurgitation depends on anatomical factors of the valve, such as the flexibility of the anterior leaflet and the presence of calcified lesions at the level of the subvalvular apparatus, but also on the experience of the center in complex mitral repair. All this means that this underdiagnosed pathology has been relegated to prosthetic replacement, since in many cases it is remitted late with advanced calcification. In order to demystify this entity, in the following article we will address rheumatic mitral regurgitation and its treatment with specific repair techniques, as well as the presentation of our experience and a discussion of the pathology with a review of the literature.

High dose haemodialysis and haemodiafiltration parameters and the relationship with advanced vascular calcification

BackgroundVascular calcification (VC) is a risk factor for cardiovascular disease in end-stage renal disease (ESRD) patients undergoing maintenance haemodialysis (MHD). However, evidence is still insufficient about the association between dialysis parameters and VC. Thus, this study was to evaluate association of dialysis parameters with VC.MethodsWe enrolled 297 ESRD patients undergoing MHD at six distinct centers in Korea. Study participants were categorized into 3 groups by the scoring system of abdominal aortic calcification based on lateral lumbar radiography (no VC group: 0, mild VC group: 1–7 and advanced VC group: 8–24). We compared the features of dialysis parameters according to the severity of VC. Multivariate logistic regression analysis was used to calculate adjusted odd ratios (ORs) and 95% confidence interval (CI) for mild and advanced VC in each haemodialysis parameter (adjusted OR [95% CI]).ResultsPooled Kt/V (spKt/V), equilibrated Kt/V (eKt/V), standard Kt/V (stdKt/V) and the proportion of haemodiafiltration were increased along with the severity of VC. Multivariate regression analysis indicated that advanced VC was positively associated with spKt/V (5.27 [1.51–18.41]), eKt/V (6.16 [1.45–26.10]), stdKt/V (10.67 [1.74–65.52]) and haemodiafiltration (3.27 [1.74 to 6.16]).ConclusionHigh dose dialysis and haemodiafiltration were significantly associated with advanced VC.

Investigation of air pollution and noise on progression of thoracic aortic calcification: results of the Heinz Nixdorf Recall Study.

AimsAir pollution and noise are potential risk factors for subclinical atherosclerosis. Longitudinal analyses, especially on the interplay of these environmental factors, are scarce and inconsistent. Hence we investigated long-term traffic-related exposure to air pollution and noise with the development and progression of thoracic aortic calcification, a marker of subclinical atherosclerosis.MethodsWe used baseline (2000–2003) and follow-up (2006–2008) data from the German Heinz Nixdorf Recall cohort study, including 4814 middle-aged adults. Residence-based air pollution (PM2.5 (aerodynamic diameter ≤ 2.5 µm), PM10, nitrogen dioxide and particle number), and noise was assessed with dispersion models. Thoracic aortic calcification was quantified from non-contrast enhanced electron beam computed tomography. The presence and extent of thoracic aortic calcification progression were analysed with multiple logistic and linear regression models, respectively, adjusting for age, sex, lifestyle variables, socioeconomic status and respective co-exposure.ResultsWe observed no association in the full study sample (n = 3155, mean age 59.1 (±7.6) years, 52.8% women). While an interquartile range in particle number and night-time noise yielded odds ratios of 1.20 (1.03, 1.40) and 1.21 (1.00, 1.46) for binary thoracic aortic calcification progression, and 0.02 (–0.01, 0.05) and 0.04 (0.00, 0.07) higher growth rates of thoracic aortic calcification in participants with baseline thoracic aortic calcification less than 10, negative findings were observed in those with baseline thoracic aortic calcification of 10 or greater. Results were similar for other pollutants and daytime noise.ConclusionOur study shows no overall associations. Subgroup analyses suggest independent associations of traffic-related air pollution and noise with the development and progression of subclinical atherosclerosis in participants with no or minor thoracic aortic calcification at baseline, in contrast to negative findings in those with advanced calcification.

Advanced calcification of a left atrial myxoma.

Advanced calcification of a left atrial myxoma.

Vascular Calcification in Chronic Kidney Disease: The Role of Inflammation.

Cardiovascular complications are extremely frequent in patients with chronic kidney disease (CKD) and death from cardiac causes is the most common cause of death in this particular population. Cardiovascular disease is approximately 3 times more frequent in patients with CKD than in other known cardiovascular risk groups and cardiovascular mortality is approximately 10-fold more frequent in patients on dialysis compared to the age- and sex-matched segments of the nonrenal population. Among other structural and functional factors advanced calcification of atherosclerotic plaques as well as of the arterial and venous media has been described as potentially relevant for this high cardiovascular morbidity and mortality. One potential explanation for this exceedingly high vascular calcification in animal models as well as in patients with CKD increased systemic and most importantly local (micro)inflammation that has been shown to favor the development of calcifying particles by multiple ways. Of note, local vascular upregulation of proinflammatory and proosteogenic molecules is already present at early stages of CKD and may thus be operative for vascular calcification. In addition, increased expression of costimulatory molecules and mast cells has also been documented in patients with CKD pointing to a more inflammatory and potentially less stable phenotype of coronary atherosclerotic plaques in CKD.

Village Index Analysis Building to Know The Village Development In Gadingrejo District of Pringsewu District

Village development Index is an index used to determine of rural development by using indicators of Social Security Index (IKS), Economic Resilience Index (IKE), and Environmental Resilience Index (IKL). The purpose of this study is to determine the pattern of development of village development in the social, economic, and environmental fields. This research uses descriptive Quantitative approach. Analysis this study using triangulation data analysis. The results showed that the majority of villages in Gadingrejo sub-district belong to the Classification of Developing Villages of 87%. The Social Security Index score is the highest indicator in the realization of village development in Gadingrejo sub-district, which is 0.71. This shows the average of villages in the sub-district of gadingrejo social resilience / social development is in advanced calcification. The village community empowerment activities in Gadingrejo are able to contribute positively in promoting social resilience.

Vitamin D toxicosis

Vitamin D compounds are found in a number of different products. Vitamin D toxicosis in companion animals commonly occurs following ingestion of human psoriasis creams containing vitamin D compounds, or of colecalciferol rodenticide baits (where available) and, less commonly, from ingestion of vitamin D supplements. The signs of poisoning can be delayed (depending on the compound) and are initially non-specific and easily missed or misdiagnosed. Initial gastrointestinal signs progress as the calcium concentration rises, and neurological and cardiac signs develop. Aggressive treatment is essential and is aimed at ensuring adequate hydration and urine output and controlling calcium concentrations and reducing phosphorous concentrations, using intravenous saline, furosemide, corticosteroids, an antiemetic, gastroprotectants, a phosphate binder and a bisphosphonate. Treatment may last days or weeks. If the calcium concentration can be controlled before the onset of severe signs the prognosis is good, but advanced calcification of tissues has a poor prognosis.

The GuideLiner catheter: A supportive tool in percutaneous coronary intervention of chronic total occlusion

BackgroundFailure of delivering a stent or a balloon across the target lesion during percutaneous coronary intervention (PCI) of chronic total occlusion (CTO), especially in arteries with calcified tortuous anatomy, is often due to insufficient backup support from the guiding catheter. The purpose of this study was to assess the feasibility of the GuideLiner (GL) catheter use. MethodsWe examined 18 patients and used the GL catheter to overcome poor support and excessive friction in standardized antegrade and retrograde CTO procedures. The GL is a coaxial, monorail guiding catheter extension delivered through a standard guiding catheter and is available in different sizes. ResultsAlmost all lesions were classified as severely calcified (94.4±0.24%). The Japanese CTO score reflecting lesion complexity was 3.56±0.78. All procedures were performed femorally; the retrograde approach was used in 27.8±0.46% of cases. The overall success rate was 88.9±0.32%; there were no relevant complications. ConclusionsThe GL catheter is an adjunctive interventional device which enhances and amplifies CTO-PCI. Its use is indicated in cases in which back-up force needs to be strengthened to pass a CTO despite advanced calcification. It can be recommended as an important additional tool in advanced interventional cardiology such as antegrade and retrograde CTO-PCI if other techniques like anchor balloon or anchor wire are not possible.

Relation of serum homocysteine levels to cerebral artery calcification and atherosclerosis

Background and aimsElevated serum homocysteine level is known to be associated with increased risk of vascular event due to endothelial senescence. We investigated the association between serum homocysteine level and cerebral arteriosclerosis status including intracranial vascular calcification and atherosclerosis burden. MethodsWe identified 1193 consecutive patients (mean age = 68.6 ± 12.7, 537 female patients) who were admitted with acute cerebral infarction or transient ischemic attack from a single university medical center. The patients were categorized into three groups according to their serum homocysteine level. Cerebral artery calcification was assessed from the cavernous portion of both internal carotid arteries, and cerebral atherosclerosis burden was derived as the sum of stenosis degree of major intracranial arteries from brain computed tomography angiography. ResultsThe mean homocysteine level was 14.1 ± 6.2 μmol/L, and intracranial cerebral artery calcification was present in 974 patients (81.6%), with 339 cases of advanced calcification (28.4%). The prevalence of cerebral artery calcification, advanced cerebral artery calcification and cerebral atherosclerosis burden showed increasing tendency throughout the homocysteine tertiles. Multivariable logistic regression analysis including age, sex, vascular risk factors, serum C-reactive protein, estimated glomerular filtration rate and homocysteine tertile disclosed that the highest serum homocysteine tertile was an independent predictor of advanced cerebral artery calcification (odds ratio = 1.45, confidence interval = 1.02–2.05) and advanced cerebral atherosclerosis (odds ratio = 1.42, confidence interval = 1.01–1.99) compared to the lowest group. ConclusionsAn elevated serum homocysteine level was independently associated with intracranial arterial calcification and atherosclerosis burden. Future studies are warranted to test whether lowering serum homocysteine can delay cerebral arteriosclerotic changes.

Should Chronic Total Occlusion Be Treated With Coronary Artery Bypass Grafting? Chronic Total Occlusion Should Be Treated With Coronary Artery Bypass Grafting.

Coronary artery chronic total occlusions (CTOs) are an exacerbation of stable coronary artery disease (CAD) with advanced calcification. CTOs are defined as 100% coronary occlusions with Thrombolysis in Myocardial Infarction grade 0 flow persisting for >3 months.1 National database registries and large single-center series suggest that in patients with CAD the overall incidence of CTOs may vary from 16% to 19% in Japan2 and 29% to 33% in North America,3 making this a common problem globally. Treatment of CTOs should be considered if associated with symptoms or viable/ischemic myocardial territories. Historically, treatments have been via coronary artery bypass grafting (CABG) or medical therapy.3–9 Response by Weintraub and Garratt on p 1817 The use of percutaneous coronary intervention (PCI) to treat CTOs (CTO-PCI) against established practice is controversial.10 This controversy is facilitated by the poor evidence available and by lack of clarity in the European and American guidelines for revascularization, including those for patients with stable CAD.11–15 The lack of robust evidence and the unclear guidelines can lead to ill-defined clinical indications determining serious geographical discrepancies in CTO-PCI medical practice. In a recent report from Japan, >61% of patients diagnosed with CTOs (19% of all CAD patients) were treated with CTO-PCI.2 This is a significant increase compared with a previous report from North America in which only 6% to 9% of all CTOs (29%–33% of all CAD cases) were treated with CTO-PCI (range, 1%–16% by geographical area/center).3 The report by Yamamoto and coworkers2 suggests widespread use of CTO-PCI in patients with multivessel CAD. This is likely to be at the expense of more established treatments such as CABG. The difference in CTO-PCI practice observed between Japan and North America is not easily explained. Contributing factors may be differences …

Abstract WP159: The Association Between Cerebral Artery Calcification and Homocysteine Among Stroke Patients

Introduction: Elevated serum homocysteine level is known to be associated with increased risk of atherosclerosis and cardiovascular event possibly through endothelial senescence. Also, homocysteine was reported to be a potential regulator of vascular calcification in animal study. Hypothesis: We hypothesized that elevated homocysteine level is associated with cerebral artery calcification. Methods: We identified 708 consecutive patients (mean age 66.3+/-12.9, 297 female patients) who were admitted with acute ischemic stroke or transient ischemic attack. Cerebral artery calcification was assessed from brain CT angiography, and advanced calcification was determined when calcification involved long (more than 1 cm) or thick (50% or more of vessel diameter) segment of distal cavernous internal carotid artery. Hyperhomocyseinemia was defined as serum homocysteine level exceeding 15 umol/L on admission. Results: Cerebral artery calcification from brain CT angiography was present in 546 patients (77.2%). Advanced cerebral artery calcification was detected in 156 patients (22.1%), and hyperhomocysteienemia was detected in 171 patients (24.2%). On bivariate analysis, advanced cerebral artery calcification was associated with hypertension, diabetes mellitus, smoking, atrial fibrillation, previous stroke history, high-sensitivity C-reactive protein (hs-CRP) and elevated homocysteine level. Multivariate logistic regression analysis including hyperhomocysteinemia, vascular risk factors, age&gt;70 years and hsCRP&gt;2.0mg/dL showed that hyperhomocysteinemia is independently associated with advanced cerebral artery calcification (odds ratio 1.8, confidence interval 1.1-2.8, p=0.011). Conclusion: Hyperhomocysteinemia was associated with advanced cerebral artery calcification. Our study suggests that homocysteine may be used as a biomarker for cerebral artery calcification.

Surgical treatment of constrictive pericarditis complicated by advanced calcification

Surgical treatment of constrictive pericarditis complicated by advanced calcification

The Extracellular Calcium-Sensing Receptor as a Contributor in Human Cartilaginous Endplate Degeneration

Introduction Intervertebral discs (IVDs) are virtually avascular tissue relying on the diffusion of nutrients and metabolites from blood vessels in the outer annulus fibrosus, and in the vertebral bodies that partially penetrate the subchondral plate, and terminate at the cartilaginous endplate (CEP). Degeneration of CEP is viewed as a catalyst to IVD degeneration, as it impedes nutrient diffusion to the disc. Similar to articular cartilage, degeneration of CEP involves decreased proteoglycan and type II collagen (Col II) content, thinning, increased type X collagen (Col X), and advanced calcification. Although biological repair strategies of the degenerative disc involving supplementation of growth factors are being pursued, disc nutrition is an important factor in considering their success in disc repair. The extracellular calcium-sensing receptor (CaSR) is a G protein-coupled receptor, and currently, is the only known mechanism in sensing both local and systemic calcium fluctuations. CaSR is the principle regulator of parathyroid hormone synthesis and secretion from the parathyroid gland, and in addition to its expression in other calcium-handling tissues (intestine, kidney), evidence suggests a direct involvement in bone and cartilage development. Recently, CaSR has been shown to modulate vascular calcification; however, its function in the calcification of other tissues remains unknown. Objectives Calcification of CEP is suggested to be a catalyst in the degeneration of IVDs. However, the mechanism(s) of CEP degeneration are currently unknown. We propose that CaSR activation modulates the degeneration of CEP, by increasing the expression of catabolic factors in CEP chondrocytes, resulting from the accumulation of ionic calcium in the milieu. Materials and Methods Human CEPs were obtained from donor IVDs of Thompson grades 2, 3, and 4 through organ donations within 24 hours of death. CEP chondrocytes were isolated from tissue by sequential digestion with pronase followed by collagenase. Cells were expanded for 7 days under standard cell culture conditions. Immunohistochemistry was performed on CEP tissue to validate the grade and expression of CaSR. Free calcium levels were also measured and compared between grades. Immunocytochemistry, Western blotting, and MAPK signaling were performed on cultured CEP chondrocytes of various grades to demonstrate expression of CaSR and degenerative markers, including the function of the receptor. CEP cells of various grades were cultured in medium containing either high calcium (5 mM Ca2+), CaSR allosteric agonist (cinacalcet, 1 µM), or regular growth medium (control, 1 mM Ca2+) for 7 days, and monitored for changes in markers of degeneration and CaSR expression. Results Ionic calcium content in CEP tissue increased significantly with IVD degeneration (Fig. A). Interestingly, immunohistochemistry on CEP tissue also revealed an increase in the expression of CaSR that paralleled the degree of IVD degeneration. Immunocytochemistry and Western blotting on isolated CEP cells demonstrated an upregulation of CaSR (Fig. B) and type X collagen that varied with Thompson grades. The expression of matrix metalloproteinase (MMP)-13 was also increased with degeneration; however, the expression of Col II and the proteoglycan aggrecan (Agg) were inversely related to Thompson grade. The magnitude of CaSR signaling in CEP cells when stimulated with 5 mM Ca2+, as determined by ERK phosphorylation, was significantly enhanced in grade 4 versus grade 2 CEP chondrocytes. To determine a role of CaSR in the degeneration of CEP, we cultured Thompson grade 2 CEP chondrocytes in 1 mM Ca2+ (control medium), 5 mM Ca2+ or cinacalcet (allosteric CaSR agonist, 1 µM) for 7 days. Western blot analysis on lysate from G2 CEP cells treated with 5 mM Ca2+ or cinacalcet demonstrated significant increases in the expression of Col X and MMP-13 (Figs. D and E), however, decreased expression of Col II and Agg was observed (Fig. C). Conclusion CaSR has been described as a mediator in ectopic calcification, and its expression is upregulated in CEP of degenerative discs. We provide evidence that CaSR upregulation may be a hallmark of CEP calcification. Activation of CaSR either by its agonist, calcium or cinacalcet, lead to increases in the synthesis of degenerative factors (Col X and MMP-13), and decreases in the production of matrix proteins (Col II and Agg). An understanding on the mechanism(s) of CEP degeneration is key when considering growth factor substitution in IVD repair, as disc nutrition may be an important factor in determining their success. Disclosure of Interest None declared References Lotz JC, Fields AJ, Liebenberg EC. The role of the vertebral end plate in low back pain. Global Spine J 2013;3(3):153–164 Brown EM. Role of the calcium-sensing receptor in extracellular calcium homeostasis. Best Pract Res Clin Endocrinol Metab 2013;27(3):333–343

The roles of various metabolic enzymes in diabetic cardiomyopathy—in vivo and in vitro approach

showed larger atheroma size, more advanced calcification, greater macrophage accumulation in arteries and fat, and greater fat deposition, as compared to control Ldlr−/− mice. Notch3tg: Ldlr−/− macrophages expressed higher levels of M1 genes. Conclusions: These results suggest that Dll4-Notch3 signaling plays a central role in the shared mechanism for the pathogenesis of atherosclerotic vascular diseases and metabolic disorders.