Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Database
Language
Publication year range
1.
J Obstet Gynaecol Can ; 43(11): 1292-1295, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33412303

ABSTRACT

Idiopathic intracranial hypertension (IIH) is a syndrome characterized by elevated intracranial pressure without an identifiable underlying cause. Pregnancy has unique and important diagnostic and therapeutic implications for patients with IIH. Despite these implications, there are no guidelines to assist clinicians in managing IIH during pregnancy. Our review aims to summarize the key considerations related to the diagnosis and management of IIH during pregnancy, to optimize the care of these patients and mitigate the risk of disease-related complications. The optimal management of IIH in pregnancy should include a multidisciplinary team, including an obstetrician (or maternal-fetal medicine specialist), a neurologist, and an ophthalmologist (or neuro-ophthalmologist).


Subject(s)
Pseudotumor Cerebri , Female , Humans , Pregnancy , Pseudotumor Cerebri/diagnosis , Pseudotumor Cerebri/therapy
2.
Can J Cardiol ; 36(4): 543-553, 2020 04.
Article in English | MEDLINE | ID: mdl-31837891

ABSTRACT

BACKGROUND: Empagliflozin, an SGLT2 inhibitor, has shown remarkable reductions in cardiovascular mortality and heart failure admissions (EMPA-REG OUTCOME). However, the mechanism underlying the heart failure protective effects of empagliflozin remains largely unknown. Cardiac fibroblasts play an integral role in the progression of structural cardiac remodelling and heart failure, in part, by regulating extracellular matrix (ECM) homeostasis. The objective of this study was to determine if empagliflozin has a direct effect on human cardiac myofibroblast-mediated ECM remodelling. METHODS: Cardiac fibroblasts were isolated via explant culture from human atrial tissue obtained at open heart surgery. Collagen gel contraction assay was used to assess myofibroblast activity. Cell morphology and cell-mediated ECM remodelling was examined with the use of confocal microscopy. Gene expression of profibrotic markers was assessed with the use of reverse-transcription quantitative polymerase chain reaction. RESULTS: Empagliflozin significantly attenuated transforming growth factor ß1-induced fibroblast activation via collagen gel contraction after 72-hour exposure, with escalating concentrations (0.5 µmol/L, 1 µmol/L, and 5 µmol/L) resulting in greater attenuation. Morphologic assessment showed that myofibroblasts exposed to empagliflozin were smaller in size with shorter and fewer number of extensions, indicative of a more quiescent phenotype. Moreover, empagliflozin significantly attenuated cell-mediated ECM remodelling as measured by collagen fibre alignment index. Gene expression profiling revealed significant suppression of critical profibrotic markers by empagliflozin, including COL1A1, ACTA2, CTGF, FN1, and MMP-2. CONCLUSIONS: We provide novel data showing a direct effect of empagliflozin on human cardiac myofibroblast phenotype and function by attenuation of myofibroblast activity and cell-mediated collagen remodelling. These data provide critical insights into the profound effects of empagliflozin as noted in the EMPA-REG OUTCOME study.


Subject(s)
Benzhydryl Compounds/pharmacology , Extracellular Matrix/drug effects , Extracellular Matrix/physiology , Glucosides/pharmacology , Myocardium/cytology , Myofibroblasts/drug effects , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Cells, Cultured , Humans
3.
J Thorac Cardiovasc Surg ; 156(4): 1598-1608.e1, 2018 10.
Article in English | MEDLINE | ID: mdl-29859675

ABSTRACT

OBJECTIVE: Intrapericardial fibrous adhesions increase the risk of sternal reentry. Proteoglycan 4/lubricin (PRG4) is a mucin-like glycoprotein that lubricates tissue compartments and prevents inflammation. We characterized PRG4 expression in human pericardium and examined its effects in vitro on human cardiac myofibroblast fibrotic activity and in vivo as a measure of its therapeutic potential to prevent adhesions. METHODS: Full-length PRG4 expression was determined using Western blot analysis and amplified luminescent proximity homogeneous assay in human pericardial tissues obtained at cardiotomy. The in vitro effects of PRG4 were investigated on human cardiac myofibroblasts for cell adhesion, collagen gel contraction, and cell-mediated extracellular matrix remodeling. The influence of PRG4 on pericardial homeostasis was determined in a chronic porcine animal model. RESULTS: PRG4 is expressed in human pericardial fluid and colocalized with pericardial mesothelial cells. Recombinant human PRG4 prevented human cardiac myofibroblast attachment and reduced myofibroblast activity assessed using collagen gel contraction assay (64.6% ± 8.1% vs 47.1% ± 6.8%; P = .02). Using a microgel assay, human cardiac myofibroblast mediated collagen fiber remodeling was attenuated by PRG4 (1.17 ± 0.03 vs 0.90 ± 0.05; P = .002). In vivo, removal of pericardial fluid alone induced severe intrapericardial adhesion formation, tissue thickening, and inflammatory fluid collections. Restoration of intrapericardial PRG4 was protective against fibrous adhesions and preserved the pericardial space. CONCLUSIONS: For the first time, we show that PRG4 is expressed in human pericardial fluid and regulates local fibrotic myofibroblast activity. Loss of PRG4-enriched pericardial fluid after cardiotomy might induce adhesion formation. Therapeutic restoration of intrapericardial PRG4 might prevent fibrous/inflammatory adhesions and reduce the risk of sternal reentry.


Subject(s)
Myofibroblasts/drug effects , Pericardium/drug effects , Proteoglycans/pharmacology , Thoracic Diseases/prevention & control , Animals , Cell Adhesion/drug effects , Cells, Cultured , Collagen/metabolism , Disease Models, Animal , Extracellular Matrix/drug effects , Extracellular Matrix/metabolism , Extracellular Matrix/pathology , Humans , Myofibroblasts/metabolism , Myofibroblasts/pathology , Pericardial Fluid/metabolism , Pericardium/metabolism , Pericardium/pathology , Proteoglycans/metabolism , Sus scrofa , Thoracic Diseases/metabolism , Thoracic Diseases/pathology , Tissue Adhesions
4.
Tissue Eng Part A ; 24(1-2): 128-134, 2018 01.
Article in English | MEDLINE | ID: mdl-28457186

ABSTRACT

Extracellular matrix (ECM) maintains a reservoir of bioactive growth factors and matricellular proteins that provide bioinductive effects on local cells that influence phenotype and behaviors. Bioactive acellular ECM scaffolds can be used therapeutically to stimulate adaptive tissue repair. Fibroblast growth factor-2 (FGF-2) attenuates transforming growth factor-ß1 (TGF-ß1)-mediated cardiac fibrosis. Heparin glycosaminoglycan can influence FGF-2 bioactivity and could be leveraged to enhance tissue engineering strategies. We explored the effects of heparin on FGF-2 enhancement of bioactive ECM scaffold biomaterials for its antifibrotic effect on attenuating human cardiac myofibroblast activation. Increasing heparin concentration at a fixed concentration of FGF-2 markedly increased the amount of FGF-2 retained and eluted by ECM scaffolds. To explore synergistic bioinductive effects of heparin and FGF-2, collagen gel contraction assay using human cardiac myofibroblasts was performed in vitro. Myofibroblast activation was induced by profibrotic cytokine, TGF-ß1. FGF-2 and heparin in combination reduced human cardiac myofibroblast-mediated collagen gel contraction to a greater extent than FGF-2 alone. These observations were confirmed for both human atrial and human ventricular cardiac fibroblasts. Cell death was not different between groups. In summary, heparin is an effective adjuvant to enhance FGF-2 loading and elution of acellular ECM scaffold biomaterials. Heparin increases the bioactive effects of FGF-2 in attenuating human cardiac myofibroblast activation in response to profibrotic TGF-ß1. These data may inform tissue engineering strategies for myocardial repair to prevent fibrosis.


Subject(s)
Extracellular Matrix/chemistry , Heparin/chemistry , Myocardium/cytology , Tissue Scaffolds/chemistry , Animals , Apoptosis/drug effects , Blotting, Western , Fibroblast Growth Factor 2/chemistry , Fibroblast Growth Factor 2/pharmacology , Heparin/pharmacology , Myofibroblasts/cytology , Myofibroblasts/drug effects , Swine , Transforming Growth Factor beta1/chemistry , Transforming Growth Factor beta1/pharmacology
SELECTION OF CITATIONS
SEARCH DETAIL
...