Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Language
Publication year range
1.
Sci Rep ; 8(1): 4961, 2018 03 21.
Article in English | MEDLINE | ID: mdl-29563538

ABSTRACT

Vascular calcification (VC) is the process of deposition of calcium phosphate crystals in the blood vessel wall, with a central role for vascular smooth muscle cells (VSMCs). VC is highly prevalent in chronic kidney disease (CKD) patients and thought, in part, to be induced by phosphate imbalance. The molecular mechanisms that regulate VC are not fully known. Here we propose a novel role for the mineralisation regulator Ucma/GRP (Upper zone of growth plate and Cartilage Matrix Associated protein/Gla Rich Protein) in phosphate-induced VSMC calcification. We show that Ucma/GRP is present in calcified atherosclerotic plaques and highly expressed in calcifying VSMCs in vitro. VSMCs from Ucma/GRP-/- mice showed increased mineralisation and expression of osteo/chondrogenic markers (BMP-2, Runx2, ß-catenin, p-SMAD1/5/8, ALP, OCN), and decreased expression of mineralisation inhibitor MGP, suggesting that Ucma/GRP is an inhibitor of mineralisation. Using BMP signalling inhibitor noggin and SMAD1/5/8 signalling inhibitor dorsomorphin we showed that Ucma/GRP is involved in inhibiting the BMP-2-SMAD1/5/8 osteo/chondrogenic signalling pathway in VSMCs treated with elevated phosphate concentrations. Additionally, we showed for the first time evidence of a direct interaction between Ucma/GRP and BMP-2. These results demonstrate an important role of Ucma/GRP in regulating osteo/chondrogenic differentiation and phosphate-induced mineralisation of VSMCs.


Subject(s)
Atherosclerosis/pathology , Bone Morphogenetic Protein 2/metabolism , Plaque, Atherosclerotic/pathology , Proteins/metabolism , Vascular Calcification/pathology , Animals , Aorta/cytology , Aorta/pathology , Biomarkers/metabolism , Cells, Cultured , Chondrogenesis/drug effects , Disease Models, Animal , Extracellular Matrix Proteins , Gene Expression Regulation/drug effects , Humans , Intracellular Signaling Peptides and Proteins , Mice , Mice, Inbred C57BL , Mice, Knockout, ApoE , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/pathology , Myocytes, Smooth Muscle/pathology , Phosphates/adverse effects , Primary Cell Culture , Protein Binding , Proteins/genetics , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Signal Transduction/drug effects , Smad Proteins/metabolism , Vascular Calcification/chemically induced
2.
PLoS One ; 10(6): e0130484, 2015.
Article in English | MEDLINE | ID: mdl-26090792

ABSTRACT

OBJECTIVE: To investigate therapeutic effects of annexin A1 (anxA1) on atherogenesis in LDLR-/- mice. METHODS: Human recombinant annexin A1 (hr-anxA1) was produced by a prokaryotic expression system, purified and analysed on phosphatidylserine (PS) binding and formyl peptide receptor (FPR) activation. Biodistribution of 99mTechnetium-hr-anxA1 was determined in C57Bl/6J mice. 12 Weeks old LDLR-/- mice were fed a Western Type Diet (WTD) during 6 weeks (Group I) or 12 weeks (Group P). Mice received hr-anxA1 (1 mg/kg) or vehicle by intraperitoneal injection 3 times per week for a period of 6 weeks starting at start of WTD (Group I) or 6 weeks after start of WTD (Group P). Total aortic plaque burden and phenotype were analyzed using immunohistochemistry. RESULTS: Hr-anxA1 bound PS in Ca2+-dependent manner and activated FPR2/ALX. It inhibited rolling and adherence of neutrophils but not monocytes on activated endothelial cells. Half lives of circulating 99mTc-hr-anxA1 were <10 minutes and approximately 6 hours for intravenously (IV) and intraperitoneally (IP) administered hr-anxA1, respectively. Pharmacological treatment with hr-anxA1 had no significant effect on initiation of plaque formation (-33%; P = 0.21)(Group I) but significantly attenuated progression of existing plaques of aortic arch and subclavian artery (plaque size -50%, P = 0.005; necrotic core size -76% P = 0.015, hr-anxA1 vs vehicle) (Group P). CONCLUSION: Hr-anxA1 may offer pharmacological means to treat chronic atherogenesis by reducing FPR-2 dependent neutrophil rolling and adhesion to activated endothelial cells and by reducing total plaque inflammation.


Subject(s)
Annexin A1/pharmacology , Plaque, Atherosclerotic/genetics , Plaque, Atherosclerotic/pathology , Receptors, LDL/deficiency , Recombinant Proteins , Animals , Annexin A1/administration & dosage , Blood Cells/metabolism , Bone Marrow Cells/metabolism , Diet, Western/adverse effects , Disease Models, Animal , Disease Progression , Drug Administration Routes , Humans , Immunophenotyping , Macrophages/drug effects , Macrophages/metabolism , Macrophages/pathology , Mice , Mice, Knockout , Plaque, Atherosclerotic/drug therapy , Plaque, Atherosclerotic/etiology , Receptors, LDL/genetics
3.
Arterioscler Thromb Vasc Biol ; 35(2): 399-408, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25538207

ABSTRACT

OBJECTIVE: Vascular and valvular calcifications are pathological processes regulated by resident cells, and depending on a complex interplay between calcification promoters and inhibitors, resembling skeletal metabolism. Here, we study the role of the vitamin K-dependent Gla-rich protein (GRP) in vascular and valvular calcification processes. APPROACH AND RESULTS: Immunohistochemistry and quantitative polymerase chain reaction showed that GRP expression and accumulation are upregulated with calcification simultaneously with osteocalcin and matrix Gla protein (MGP). Using conformation-specific antibodies, both γ-carboxylated GRP and undercarboxylated GRP species were found accumulated at the sites of mineral deposits, whereas undercarboxylated GRP was predominant in calcified aortic valve disease valvular interstitial cells. Mineral-bound GRP, MGP, and fetuin-A were identified by mass spectrometry. Using an ex vivo model of vascular calcification, γ-carboxylated GRP but not undercarboxylated GRP was shown to inhibit calcification and osteochondrogenic differentiation through α-smooth muscle actin upregulation and osteopontin downregulation. Immunoprecipitation assays showed that GRP is part of an MGP-fetuin-A complex at the sites of valvular calcification. Moreover, extracellular vesicles released from normal vascular smooth muscle cells are loaded with GRP, MGP, and fetuin-A, whereas under calcifying conditions, released extracellular vesicles show increased calcium loading and GRP and MGP depletion. CONCLUSIONS: GRP is an inhibitor of vascular and valvular calcification involved in calcium homeostasis. Its function might be associated with prevention of calcium-induced signaling pathways and direct mineral binding to inhibit crystal formation/maturation. Our data show that GRP is a new player in mineralization competence of extracellular vesicles possibly associated with the fetuin-A-MGP calcification inhibitory system. GRP activity was found to be dependent on its γ-carboxylation status, with potential clinical relevance.


Subject(s)
Aortic Valve Stenosis/prevention & control , Aortic Valve/pathology , Calcinosis/prevention & control , Calcium/metabolism , Coronary Artery Disease/prevention & control , Proteins/metabolism , Vascular Calcification/prevention & control , Actins/metabolism , Adult , Aged , Aged, 80 and over , Aorta/metabolism , Aorta/pathology , Aortic Valve/metabolism , Aortic Valve Stenosis/genetics , Aortic Valve Stenosis/metabolism , Aortic Valve Stenosis/pathology , Calcinosis/genetics , Calcinosis/metabolism , Calcinosis/pathology , Calcium-Binding Proteins/genetics , Calcium-Binding Proteins/metabolism , Case-Control Studies , Coronary Artery Disease/genetics , Coronary Artery Disease/metabolism , Coronary Artery Disease/pathology , Coronary Vessels/metabolism , Coronary Vessels/pathology , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Female , Gene Expression Regulation , Humans , Intercellular Signaling Peptides and Proteins , Intracellular Signaling Peptides and Proteins , Male , Middle Aged , Osteocalcin/genetics , Osteocalcin/metabolism , Proteins/genetics , Tissue Culture Techniques , Vascular Calcification/genetics , Vascular Calcification/metabolism , Vascular Calcification/pathology , alpha-2-HS-Glycoprotein/metabolism , Matrix Gla Protein
4.
Mol Nutr Food Res ; 58(8): 1636-46, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24867294

ABSTRACT

SCOPE: Gla-rich protein (GRP) is a vitamin K dependent protein, characterized by a high density of γ-carboxylated Glu residues, shown to accumulate in mouse and sturgeon cartilage and at sites of skin and vascular calcification in humans. Therefore, we investigated the involvement of GRP in pathological calcification in osteoarthritis (OA). METHODS AND RESULTS: Comparative analysis of GRP patterning at transcriptional and translational levels was performed between controls and OA patients. Using a RT-PCR strategy we unveiled two novel splice variants in human-GRP-F5 and F6-potentially characterized by the loss of full γ-carboxylation and secretion functional motifs. GRP-F1 is shown to be the predominant splice variant expressed in mouse and human adult tissues, particularly in OA cartilage, while an overexpressing human cell model points it as the major γ-carboxylated isoform. Using validated conformational antibodies detecting carboxylated or undercarboxylated GRP (c/uc GRP), we have demonstrated cGRP accumulation in controls, whereas ucGRP was the predominant form in OA-affected tissues, colocalizing at sites of ectopic calcification. CONCLUSION: Overall, our results indicate the predominance of GRP-F1, and a clear association of ucGRP with OA cartilage and synovial membrane. Levels of vitamin K should be further assessed in these patients to determine its potential therapeutic use as a supplement in OA treatment.


Subject(s)
Alternative Splicing , Calcinosis/etiology , Cartilage/metabolism , Osteoarthritis/metabolism , Protein Processing, Post-Translational , Proteins/metabolism , Aged , Amino Acid Sequence , Animals , Cartilage/embryology , Extracellular Matrix Proteins , Female , Glutamic Acid/metabolism , HEK293 Cells , Humans , Intercellular Signaling Peptides and Proteins , Intracellular Signaling Peptides and Proteins , Male , Mice , Molecular Sequence Data , Organ Specificity , Osteoarthritis/genetics , Osteoarthritis/pathology , Osteoarthritis/physiopathology , Proteins/chemistry , Proteins/genetics , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Sequence Alignment , Species Specificity
5.
Mol Nutr Food Res ; 58(8): 1620-35, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24668744

ABSTRACT

In the past few decades vitamin K has emerged from a single-function "haemostasis vitamin" to a "multi-function vitamin." The use of vitamin K antagonists (VKA) inevitably showed that the inhibition was not restricted to vitamin K dependent coagulation factors but also synthesis of functional extrahepatic vitamin K dependent proteins (VKDPs), thereby eliciting undesired side effects. Vascular calcification is one of the recently revealed detrimental effects of VKA. The discovery that VKDPs are involved in vascular calcification has propelled our mechanistic understanding of this process and has opened novel avenues for diagnosis and treatment. This review addresses mechanisms of VKDPs and their significance for physiological and pathological calcification.


Subject(s)
Blood Coagulation , Calcification, Physiologic , Models, Biological , Vitamin K/metabolism , Animals , Anticoagulants/pharmacology , Anticoagulants/therapeutic use , Biomedical Research/trends , Blood Coagulation/drug effects , Calcification, Physiologic/drug effects , Calcinosis/etiology , Calcinosis/prevention & control , Calcinosis/therapy , Humans , Vitamin K/antagonists & inhibitors , Vitamin K/therapeutic use , Vitamin K Deficiency/metabolism , Vitamin K Deficiency/physiopathology , Vitamin K Deficiency/therapy
SELECTION OF CITATIONS
SEARCH DETAIL
...