316 research outputs found

    Chronic Mineral Dysregulation Promotes Vascular Smooth Muscle Cell Adaptation and Extracellular Matrix Calcification

    Get PDF
    In chronic kidney disease (CKD) vascular calcification occurs in response to deranged calcium and phosphate metabolism and is characterized by vascular smooth muscle cell (VSMC) damage and attrition. To gain mechanistic insights into how calcium and phosphate mediate calcification, we used an ex vivo model of human vessel culture. Vessel rings from healthy control subjects did not accumulate calcium with long-term exposure to elevated calcium and/or phosphate. In contrast, vessel rings from patients with CKD accumulated calcium; calcium induced calcification more potently than phosphate (at equivalent calcium-phosphate product). Elevated phosphate increased alkaline phosphatase activity in CKD vessels, but inhibition of alkaline phosphatase with levamisole did not block calcification. Instead, calcification in CKD vessels most strongly associated with VSMC death resulting from calcium- and phosphate-induced apoptosis; treatment with a pan-caspase inhibitor ZVAD ameliorated calcification. Calcification in CKD vessels was also associated with increased deposition of VSMC-derived vesicles. Electron microscopy confirmed increased deposition of vesicles containing crystalline calcium and phosphate in the extracellular matrix of dialysis vessel rings. In contrast, vesicle deposition and calcification did not occur in normal vessel rings, but we observed extensive intracellular mitochondrial damage. Taken together, these data provide evidence that VSMCs undergo adaptive changes, including vesicle release, in response to dysregulated mineral metabolism. These adaptations may initially promote survival but ultimately culminate in VSMC apoptosis and overt calcification, especially with continued exposure to elevated calcium

    An approach to the use of indices-based analysis subject to money laundering and terrorist financing national risk assessment

    Get PDF
    The core aim of this study is to propose an approach to quantitate estimation of indices-based information subject to necessities of the National Risk Assessment (NRA) of money laundering and terrorist financing (ML/TF) risks. Mathematical formalization analysis for Ukraine based on 11 indices and indicators for years 2011-2015 subject to core areas of the overall situation in a country considered within its National Risk Assessment was carried out. Authors’ contribution covers scientific novelty that is a first-time analysis of a general situation in a jurisdiction in light of the National Risk Assessment’s requirements based on joint consideration of various indices and setting priority to areas of the overall country’s situation in the framework of conducted calculations. It was concluded that proposed approach is a valuable instrument for assessing priority of areas of the overall situation in the country for the National Risk Assessment’s purposes through a formalized mechanism ensuring high objectiveness. Practical significance of this study is a possibility to reach higher efficiency in allocation of available resources for the participants of the National Risk Assessment, to reduce some costs considering flexibility of the approach allowing consideration of significant volumes of information, its updating and comparison. This research could become a starting point for further research. Considering complexity of existing indices, there is a necessity to study a mechanism of their correlation and mutual influence, analyze elasticity and joint behavior, and discover the areas of preferable influence on large range of purposes not only limited to the MRA of ML/TF risks

    Kidney Function-Dependence of Vitamin K-Status Parameters:Results from the TransplantLines Biobank and Cohort Studies

    Get PDF
    High circulating dephosphorylated (dp) uncarboxylated (uc) matrix Gla protein (MGP) and uc osteocalcin (OC) concentrations are regarded as markers of vitamin K-deficiency. However, because MGP and OC are small molecules, they may potentially pass the glomerulus, and their blood concentrations may strongly depend on kidney function. However, many studies with vitamin K-status parameters do not structurally adjust for baseline kidney function, and detailed studies on kidney function-dependence of vitamin K-status markers are lacking. We therefore measured plasma dp-ucMGP using a chemiluminescent assay in 578 kidney transplant recipients (41% females, age 56 ± 13y, 7.5 (3.2 to 13.7)y after transplantation, eGFR 49 ± 17 mL/min/1.73 m(2)) participating in the prospective TransplantLines Cohort Studies. Additionally, dp-carboxylated MGP, ucOC and carboxylated OC were measured using ELISA in plasma of a subgroup of 60 participants. Finally, dp-ucMGP was measured in a separate cohort of 124 kidney transplant recipients before and three months after kidney transplantation. Dp-ucMGP positively correlated with creatinine, cystatin C, and negatively with eGFR (Spearman’s ρ 0.54, 0.60, and −0.54, respectively, p < 0.001 for all), and each 10 mL/min/1.73 m(2) increase in eGFR was associated with a 14.0% lower dp-ucMGP. Additionally, dp-ucMGP strongly declined after kidney transplantation (pretransplantation: 1252 (868 to 1744) pmol/L to posttransplantation: 609 (451 to 914) pmol/L, p < 0.001). Proportions of dp-ucMGP over total MGP and ucOC over total OC were not associated with eGFR. This study highlights that dp-ucMGP is strongly associated with kidney function, and that levels strongly decrease after kidney transplantation. We therefore propose adequate adjustment for kidney function, or the use of kidney function-independent parameters such as proportion of uncarboxylated MGP or OC in the assessment of vitamin K-status in clinical practice and research

    Calcific aortic valve stenosis:hard disease in the heart: A biomolecular approach towards diagnosis and treatment

    Get PDF
    Calcific aortic valve stenosis (CAVS) is common in the ageing population and set to become an increasing economic and health burden. Once present, it inevitably progresses and has a poor prognosis in symptomatic patients. No medical therapies are proven to be effective in holding or reducing disease progression. Therefore, aortic valve replacement remains the only available treatment option. Improved knowledge of the mechanisms underlying disease progression has provided us with insights that CAVS is not a passive disease. Rather, CAVS is regulated by numerous mechanisms with a key role for calcification. Aortic valve calcification (AVC) is actively regulated involving cellular and humoral factors that may offer targets for diagnosis and intervention. The discovery that the vitamin K-dependent proteins are involved in the inhibition of AVC has boosted our mechanistic understanding of this process and has opened up novel avenues in disease exploration. This review discusses processes involved in CAVS progression, with an emphasis on recent insights into calcification, methods for imaging calcification activity, and potential therapeutic options

    Vitamin K Antagonists, Non-Vitamin K Antagonist Oral Anticoagulants, and Vascular Calcification in Patients with Atrial Fibrillation

    Get PDF
    Background  Vitamin K antagonists (VKAs) are associated with coronary artery calcification in low-risk populations, but their effect on calcification of large arteries remains uncertain. The effect of non-vitamin K antagonist oral anticoagulants (NOACs) on vascular calcification is unknown. We investigated the influence of use of VKA and NOAC on calcification of the aorta and aortic valve. Methods  In patients with atrial fibrillation without a history of major adverse cardiac or cerebrovascular events who underwent computed tomographic angiography, the presence of ascending aorta calcification (AsAC), descending aorta calcification (DAC), and aortic valve calcification (AVC) was determined. Confounders for VKA/NOAC treatment were identified and propensity score adjusted logistic regression explored the association between treatment and calcification (Agatston score > 0). AsAC, DAC, and AVC differences were assessed in propensity score-matched groups. Results  Of 236 patients (33% female, age: 58 ± 9 years), 71 (30%) used VKA (median duration: 122 weeks) and 79 (34%) used NOAC (median duration: 16 weeks). Propensity score-adjusted logistic regression revealed that use of VKA was significantly associated with AsAC (odds ratio [OR]: 2.31; 95% confidence interval [CI]: 1.16-4.59; p  = 0.017) and DAC (OR: 2.38; 95% CI: 1.22-4.67; p  = 0.012) and a trend in AVC (OR: 1.92; 95% CI: 0.98-3.80; p  = 0.059) compared with non-anticoagulation. This association was absent in NOAC versus non-anticoagulant (AsAC OR: 0.51; 95% CI: 0.21-1.21; p  = 0.127; DAC OR: 0.80; 95% CI: 0.36-1.76; p  = 0.577; AVC OR: 0.62; 95% CI: 0.27-1.40; p  = 0.248). A total of 178 patients were propensity score matched in three pairwise comparisons. Again, use of VKA was associated with DAC ( p  = 0.043) and a trend toward more AsAC ( p  = 0.059), while use of NOAC was not (AsAC p  = 0.264; DAC p  = 0.154; AVC p  = 0.280). Conclusion  This cross-sectional study shows that use of VKA seems to contribute to vascular calcification. The calcification effect was not observed in NOAC users

    DEFICIENCY OF MYELOID PHD PROTEINS AGGRAVATES ATHEROGENESIS VIA MACROPHAGE APOPTOSIS AND PARACRINE FIBROTIC SIGNALING Atherogenic effects of myeloid PHD knockdown

    Get PDF
    AIMS: Atherosclerotic plaque hypoxia is detrimental for macrophage function. Prolyl hydroxylases (PHDs) initiate cellular hypoxic responses, possibly influencing macrophage function in plaque hypoxia. Thus, we aimed to elucidate the role of myeloid PHDs in atherosclerosis. METHODS AND RESULTS: Myeloid-specific PHD knockout (PHDko) mice were obtained via bone marrow transplantation (PHD1ko, PHD3ko) or conditional knockdown through lysozyme M-driven Cre recombinase (PHD2cko). Mice were fed high cholesterol diet for 6–12 weeks to induce atherosclerosis. Aortic root plaque size was significantly augmented 2.6-fold in PHD2cko, and 1.4-fold in PHD3ko compared to controls but was unchanged in PHD1ko mice. Macrophage apoptosis was promoted in PHD2cko and PHD3ko mice in vitro and in vivo, via the hypoxia-inducible factor (HIF) 1α/BNIP3 axis. Bulk and single-cell RNA data of PHD2cko bone marrow-derived macrophages (BMDMs) and plaque macrophages, respectively, showed enhanced HIF1α/BNIP3 signalling, which was validated in vitro by siRNA silencing. Human plaque BNIP3 mRNA was positively associated with plaque necrotic core size, suggesting similar pro-apoptotic effects in human. Furthermore, PHD2cko plaques displayed enhanced fibrosis, while macrophage collagen breakdown by matrix metalloproteinases, collagen production, and proliferation were unaltered. Instead, PHD2cko BMDMs enhanced fibroblast collagen secretion in a paracrine manner. In silico analysis of macrophage-fibroblast communication predicted SPP1 (osteopontin) signalling as regulator, which was corroborated by enhanced plaque SPP1 protein in vivo. Increased SPP1 mRNA expression upon PHD2cko was preferentially observed in foamy plaque macrophages expressing ‘triggering receptor expressed on myeloid cells-2’ (TREM2hi) evidenced by single-cell RNA, but not in neutrophils. This confirmed enhanced fibrotic signalling by PHD2cko macrophages to fibroblasts, in vitro as well as in vivo. CONCLUSION: Myeloid PHD2cko and PHD3ko enhanced atherosclerotic plaque growth and macrophage apoptosis, while PHD2cko macrophages further activated collagen secretion by fibroblasts in vitro, likely via paracrine SPP1 signalling through TREM2hi macrophages
    corecore