Magnesium but not nicotinamide prevents vascular calcification in experimental uraemia

BACKGROUND: Optimal phosphate control is an unmet need in chronic kidney disease (CKD). High serum phosphate increases calcification burden and is associated with mortality and cardiovascular disease in CKD. Nicotinamide (NA) alone or in combination with calcium-free phosphate binders might be a strategy to reduce phosphate levels and calcification and thus impact cardiovascular disease in CKD. METHODS: We studied the effect of NA alone and in combination with magnesium carbonate (MgCO3) as a potential no

Osteoprotegerin production by breast cancer cells is suppressed by dexamethasone and confers resistance against TRAIL-induced apoptosis

ABSTRACT Osteoprotegerin (OPG) is a decoy receptor for receptor activator of NF-kB ligand (RANKL) and TNF-related apoptosis-inducing ligand (TRAIL). While RANKL is essential for osteoclastogenesis and facilitates breast cancer migration into bone, TRAIL promotes breast cancer apoptosis. We analyzed the expression of OPG and TRAIL and its modulation in estrogen receptor-positive MCF-7 cells and receptor-negative MDA-MB-231 cells. In both cells, OPG mRNA levels and protein secretion were dose-and time-dependently enhanced by interleukin (IL)-1b and suppressed by dexamethasone. In contrast to MCF-7 cells, MDA-MB-231 abundantly expressed TRAIL mRNA, which was enhanced by IL-1b and inhibited by dexamethasone. TRAIL activated pro-apoptotic caspase-3, -7, and poly-ADP-ribose polymerase and decreased cell numbers of MDA-MB-231, but had no effect on MCF-7 cells. Gene silencing siRNA directed against OPG resulted in a 31% higher apoptotic rate compared to non-target siRNA-treated MDA-MB-231 cells. Furthermore, TRAIL induced significantly less apoptosis in cells cultured in conditioned media (containing OPG) compared to cells exposed to TRAIL in fresh medium lacking OPG ( P < 0.01) and these protective effects were reversed by blocking OPG with its specific ligand RANKL ( P < 0.05). The association between cancer cell survival and OPG production by MDA-MB-231 cells was further supported by the finding, that modulation of OPG secretion using IL-1b or dexamethasone prior to TRAIL exposure resulted in decreased and increased rate of apoptosis, respectively ( P < 0.05). Thus, OPG secretion by breast cancer cells is modulated by cytokines and dexamethasone, and may represent a critical resistance mechanism that protects against TRAIL-induced apoptosis

PARP9 and PARP14 cross-regulate macrophage activation via STAT1 ADP-ribosylation

Despite the global impact of macrophage activation in vascular disease, the underlying mechanisms remain obscure. Here we show, with global proteomic analysis of macrophage cell lines treated with either IFNγ or IL-4, that PARP9 and PARP14 regulate macrophage activation. In primary macrophages, PARP9 and PARP14 have opposing roles in macrophage activation. PARP14 silencing induces pro-inflammatory genes and STAT1 phosphorylation in M(IFNγ) cells, whereas it suppresses anti-inflammatory gene expression and STAT6 phosphorylation in M(IL-4) cells. PARP9 silencing suppresses pro-inflammatory genes and STAT1 phosphorylation in M(IFNγ) cells. PARP14 induces ADP-ribosylation of STAT1, which is suppressed by PARP9. Mutations at these ADP-ribosylation sites lead to increased phosphorylation. Network analysis links PARP9–PARP14 with human coronary artery disease. PARP14 deficiency in haematopoietic cells accelerates the development and inflammatory burden of acute and chronic arterial lesions in mice. These findings suggest that PARP9 and PARP14 cross-regulate macrophage activation

Genesis and growth of extracellular vesicle-derived microcalcification in atherosclerotic plaques

Clinical evidence links arterial calcification and cardiovascular risk. Finite-element modelling of the stress distribution within atherosclerotic plaques has suggested that subcellular microcalcifications in the fibrous cap may promote material failure of the plaque, but that large calcifications can stabilize it. Yet the physicochemical mechanisms underlying such mineral formation and growth in atheromata remain unknown. Here, by using three-dimensional collagen hydrogels that mimic structural features of the atherosclerotic fibrous cap, and high-resolution microscopic and spectroscopic analyses of both the hydrogels and of calcified human plaques, we demonstrate that calcific mineral formation and maturation results from a series of events involving the aggregation of calcifying extracellular vesicles, and the formation of microcalcifications and ultimately large calcification zones. We also show that calcification morphology and the plaque’s collagen content – two determinants of atherosclerotic plaque stability - are interlinked

Dissociation of osteogenic and immunological effects by the selective glucocorticoid receptor agonist, compound A, in human bone marrow stromal cells

Glucocorticoids (GCs) regulate various physiological processes, including bone remodeling. Whereas physiological amounts of GCs are required for proper human osteoblast differentiation, prolonged exposure to GCs leads to substantial bone loss in vivo predominantly by inhibiting osteoblast functions. Compound A (CpdA) is a novel GC receptor modulator with the potential of an improved benefit/risk profile. Here we tested the osteoimmunological effects of CpdA on primary human osteoblasts and their paracrine interactions with osteoclasts. To assess the anti-inflammatory potential of CpdA in human bone marrow stromal cell (BMSC)-derived osteoblasts, cells were stimulated with lipopolysaccharide and cytokine expression was determined. Similar to dexamethasone (DEX), CpdA profoundly suppressed lipopolysaccharide-induced TNF-alpha (-63%), IL-1 beta (-38%), and IL-6 (-36%) (P < 0.05) mRNA levels. Of note, CpdA failed to induce osteogenic differentiation of BMSCs, whereas DEX and budesonide enhanced matrix mineralization an d increased runt-related transcription factor 2 and alkaline phosphatase mRNA levels up to 5-fold in a dose-dependent manner. Interestingly, each substancepromotedcell proliferation by 7-10% and suppressed apoptosis by 25-30% at low concentrations and early differentiation stages, whereas high concentrations (1 mu M) suppressed proliferation and stimulated apoptosis in mature osteoblasts. Finally, CpdA did not increase the receptor activator of nuclear factor-kappa B ligand to osteoprotegerin mRNA ratio as compared with DEX and did not stimulate the formation of osteoclasts in coculture with BMSCs. In summary, CpdA displays dissociated osteogenic and immunological effects in human BMSCs that are distinct from those of conventional GCs. Whether the specific osteoimmunological profile of CpdA translates into a relevant in vivo effect needs to be further explored. (Endocrinology 152: 103-112, 2011

ПОЯСНЮВАЛЬНА ЗАПИСКА кваліфікаційної роботи бакалавра студента Козаченко Артема Олександровича групи САіт-15-2 напряму підготовки 124 Системний аналіз

Економічна ефективність: очікується позитивною завдяки аналізу web-орієнтованої системи та розробці програмного забезпечення, які дозволяють покращити відвідуваність сайту користувачами, впроваджувати монетизацію за допомогою реклами тим самим збільшуючи дохід власника. Практична значимість результатів: полягає в тому, що їх можна успішно використовувати в реальному менеджменті складних сучасних систем. Пропозиціі щодо розвитку: передбачається розглянути питання використання запропонованої концепції функціонального опису систем при проектуванні нових систем. В інформаційно-аналітичному розділі розглядаються питання опису функціональної структури web-орієнтованих інформаційних систем. Пропонується метод опису функціональних структур і метод аналізу функціональної достатньості спроектованих систем. Обговорюються практична реалізація для менеджменту систем. У спеціальному розділі описуються етапи створення мобільного додатку для сайту з метою розширення аудиторії та покращення функціональної забезпеченості системи та розроблений прогноз користувачів web-орієнтованої інформаційної системи для подальшого аналізу достатньості системи.Об’єкт дослідження: функціональна структура web-орієнтованих інформаційних систем.Предмет дослідження: методологічні основи побудови класифікацій web-орієнтованих систем та методи опису функціональних структур і аналізу функціональної достатності спроектованих систем.Мета роботи: розгляд питання опису функціональної структури проектованої інформаційної системи та покращення функціональної забезпеченості системи.Методи дослідження: метод аналізу функціональної забезпеченості інформаційної системи, методи прогнозу, мова програмування Java

Distinct role of mitochondrial function and protein kinase C in intimal and medial calcification in vitro

Introduction: Vascular calcification (VC) is a major risk factor for cardiovascular morbidity and mortality. Depending on the location of mineral deposition within the arterial wall, VC is classified as intimal and medial calcification. Using in vitro mineralization assays, we developed protocols triggering both types of calcification in vascular smooth muscle cells (SMCs) following diverging molecular pathways. Materials and methods and results: Human coronary artery SMCs were cultured in osteogenic medium (OM) or high calcium phosphate medium (CaP) to induce a mineralized extracellular matrix. OM induces osteoblast-like differentiation of SMCs–a key process in intimal calcification during atherosclerotic plaque remodeling. CaP mimics hyperphosphatemia, associated with chronic kidney disease–a risk factor for medial calcification. Transcriptomic analysis revealed distinct gene expression profiles of OM and CaP-calcifying SMCs. OM and CaP-treated SMCs shared 107 differentially regulated genes related to SMC contraction and metabolism. Real-time extracellular efflux analysis demonstrated decreased mitochondrial respiration and glycolysis in CaP-treated SMCs compared to increased mitochondrial respiration without altered glycolysis in OM-treated SMCs. Subsequent kinome and in silico drug repurposing analysis (Connectivity Map) suggested a distinct role of protein kinase C (PKC). In vitro validation experiments demonstrated that the PKC activators prostratin and ingenol reduced calcification triggered by OM and promoted calcification triggered by CaP. Conclusion: Our direct comparison results of two in vitro calcification models strengthen previous observations of distinct intracellular mechanisms that trigger OM and CaP-induced SMC calcification in vitro. We found a differential role of PKC in OM and CaP-calcified SMCs providing new potential cellular and molecular targets for pharmacological intervention in VC. Our data suggest that the field should limit the generalization of results found in in vitro studies using different calcification protocols

Integrative Multi-Omics Analysis in Calcific Aortic Valve Disease Reveals a Link to the Formation of Amyloid-Like Deposits

Calcific aortic valve disease (CAVD) is the most prevalent valvular heart disease in the developed world, yet no pharmacological therapy exists. Here, we hypothesize that the integration of multiple omic data represents an approach towards unveiling novel molecular networks in CAVD. Databases were searched for CAVD omic studies. Differentially expressed molecules from calcified and control samples were retrieved, identifying 32 micro RNAs (miRNA), 596 mRNAs and 80 proteins. Over-representation pathway analysis revealed platelet degranulation and complement/coagulation cascade as dysregulated pathways. Multi-omics integration of overlapping proteome/transcriptome molecules, with the miRNAs, identified a CAVD protein-protein interaction network containing seven seed genes (apolipoprotein A1 (APOA1), hemoglobin subunit β (HBB), transferrin (TF), α-2-macroglobulin (A2M), transforming growth factor β-induced protein (TGFBI), serpin family A member 1 (SERPINA1), lipopolysaccharide binding protein (LBP), inter-α-trypsin inhibitor heavy chain 3 (ITIH3) and immunoglobulin κ constant (IGKC)), four input miRNAs (miR-335-5p, miR-3663-3p, miR-21-5p, miR-93-5p) and two connector genes (amyloid beta precursor protein (APP) and transthyretin (TTR)). In a metabolite-gene-disease network, Alzheimer's disease exhibited the highest degree of betweenness. To further strengthen the associations based on the multi-omics approach, we validated the presence of APP and TTR in calcified valves from CAVD patients by immunohistochemistry. Our study suggests a novel molecular CAVD network potentially linked to the formation of amyloid-like structures. Further investigations on the associated mechanisms and therapeutic potential of targeting amyloid-like deposits in CAVD may offer significant health benefits