RESUMO
Gestational diabetes mellitus (GDM) affects 5-10% of pregnancies and increases the risk of fetal and maternal adverse outcomes. Interestingly, the vascular response to AngII is decreased by pregnancy while the response is increased by diabetes. It remains unclear how GDM affects vascular tone and how angiotensin II receptors contribute to these changes. In this work, we sought to establish the vascular impact of a hypercaloric diet-induced GDM through changes in AT1 and AT2 receptor's expression. Female rats fed for 7 weeks with standard (SD) or hypercaloric (HD) diet were divided at week 4. Half of the rats of each group were mated to become pregnant and those fed with a HD developed GDM. AngII-induced vasoconstriction was measured in thoracic or abdominal aorta rings using a conventional isolated organ bath and AT1 and AT2 receptors were searched by immunohistochemistry. Experiments where conducted on the pregnant standard diet group (PSD) and the pregnant hypercaloric-gestational diabetes mellitus group (PHD-GDM). Vasoconstriction was reduced in the thoracic aorta (P < 0.05 vs PSD) but increased in the abdominal aorta of PHD-GDM rats (P < 0.05 vs PSD). Blockade of AT2 receptors using PD123319 decreased vasoconstriction, particularly in the abdominal aorta of PHD-GDM animals (P < 0.05 vs PSD). PHD-GDM increased AT1 receptors expression (P < 0.05 vs PSD). Also, PHD-GDM reverted physiologic hypoglycemia and hypotension of healthy pregnancy. Findings provide new insight into the hypercaloric diet induced damage on the vasculature during pregnancy.
Assuntos
Aorta Abdominal/metabolismo , Aorta Torácica/metabolismo , Diabetes Gestacional/metabolismo , Endotélio Vascular/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/metabolismo , Vasoconstrição , Angiotensina II/farmacologia , Antagonistas de Receptores de Angiotensina/farmacologia , Animais , Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/fisiopatologia , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiopatologia , Diabetes Gestacional/fisiopatologia , Modelos Animais de Doenças , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Gravidez , Ratos Wistar , Receptor Tipo 1 de Angiotensina/agonistas , Receptor Tipo 2 de Angiotensina/agonistas , Transdução de Sinais , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologiaRESUMO
OBJECTIVE: Tissue-engineered vascular grafts containing adipose-derived mesenchymal stem cells offer an alternative to small-diameter vascular grafts currently used in cardiac and lower-extremity revascularization procedures. Adipose-derived, mesenchymal stem cell-infused, tissue-engineered vascular grafts have been shown to promote remodeling and vascular homeostasis in vivo and offer a possible treatment solution for those with cardiovascular disease. Unfortunately, the time needed to cultivate adipose-derived mesenchymal stem cells remains a large hurdle for tissue-engineered vascular grafts as a treatment option. The purpose of this study was to determine if stromal vascular fraction (known to contain progenitor cells) seeded tissue-engineered vascular grafts would remain patent in vivo and remodel, allowing for a "same-day" process for tissue-engineered vascular graft fabrication and implantation. METHODS: Stromal vascular fraction, obtained from adult human adipose tissue, was seeded within 4 hours after acquisition from the patient onto poly(ester urethane)urea bilayered scaffolds using a customized rotational vacuum seeding device. Constructs were then surgically implanted as abdominal aortic interposition grafts in Lewis rats. RESULTS: Findings revealed patency in 5 of 7 implanted scaffolds at 8 weeks, along with neotissue formation and remodeling occurring in patent tissue-engineered vascular grafts. Patency was documented using angiography and gross inspection, and remodeling and vascular components were detected using immunofluorescent chemistry. CONCLUSIONS: A "same-day" cell-seeded, tissue-engineered vascular graft can remain patent after implantation in vivo, with neotissue formation and remodeling occurring by 8 weeks.
Assuntos
Tecido Adiposo/citologia , Aorta Abdominal/cirurgia , Bioprótese , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Transplante de Células-Tronco/instrumentação , Células Estromais/fisiologia , Células Estromais/transplante , Engenharia Tecidual/métodos , Alicerces Teciduais , Adulto , Animais , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Aorta Abdominal/fisiopatologia , Biomarcadores/metabolismo , Células Cultivadas , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Neointima , Fenótipo , Desenho de Prótese , Ratos Endogâmicos Lew , Células Estromais/metabolismo , Fatores de Tempo , Transplante Heterólogo , Grau de Desobstrução Vascular , Remodelação Vascular , Fluxo de TrabalhoRESUMO
OBJECTIVE: One of the rate-limiting barriers within the field of vascular tissue engineering is the lengthy fabrication time associated with expanding appropriate cell types in culture. One particularly attractive cell type for this purpose is the adipose-derived mesenchymal stem cell (AD-MSC), which is abundant and easily harvested from liposuction procedures. Even this cell type has its drawbacks, however, including the required culture period for expansion, which could pose risks of cellular transformation or contamination. Eliminating culture entirely would be ideal to avoid these concerns. In this study, we used the raw population of cells obtained after digestion of human liposuction aspirates, known as the stromal vascular fraction (SVF), as an abundant, culture-free cell source for tissue-engineered vascular grafts (TEVGs). METHODS: SVF cells and donor-paired cultured AD-MSCs were first assessed for their abilities to differentiate into vascular smooth muscle cells (SMCs) after angiotensin II stimulation and to secrete factors (eg, conditioned media) that promote SMC migration. Next, both cell types were incorporated into TEVG scaffolds, implanted as an aortic graft in a Lewis rat model, and assessed for their patency and composition. RESULTS: In general, the human SVF cells were able to perform the same functions as AD-MSCs isolated from the same donor by culture expansion. Specifically, cells within the SVF performed two important functions; namely, they were able to differentiate into SMCs (SVF calponin expression: 16.4% ± 7.7% vs AD-MSC: 19.9%% ± 1.7%) and could secrete promigratory factors (SVF migration rate relative to control: 3.1 ± 0.3 vs AD-MSC: 2.5 ± 0.5). The SVF cells were also capable of being seeded within biodegradable, elastomeric, porous scaffolds that, when implanted in vivo for 8 weeks, generated patent TEVGs (SVF: 83% patency vs AD-MSC: 100% patency) populated with primary vascular components (eg, SMCs, endothelial cells, collagen, and elastin). CONCLUSIONS: Human adipose tissue can be used as a culture-free cell source to create TEVGs, laying the groundwork for the rapid production of cell-seeded grafts.
Assuntos
Tecido Adiposo/irrigação sanguínea , Bioprótese , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Músculo Liso Vascular/transplante , Miócitos de Músculo Liso/transplante , Células Estromais/transplante , Engenharia Tecidual/métodos , Adulto , Angiotensina II/farmacologia , Animais , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Aorta Abdominal/cirurgia , Implante de Prótese Vascular/métodos , Diferenciação Celular , Movimento Celular , Separação Celular , Células Cultivadas , Feminino , Humanos , Lipectomia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Fenótipo , Ratos Endogâmicos Lew , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Fatores de Tempo , Alicerces TeciduaisRESUMO
Obstructive sleep apnea (OSA) is an independent risk factor for cardiovascular diseases such as systemic arterial hypertension, ischemic heart disease, stroke, heart failure, atrial fibrillation, and cardiac sudden death. The pathogenesis of cardiovascular disease in OSA is thought to be induced primarily by chronic intermittent hypoxia (CIH), a specific pattern of change in oxygenation during sleep. However, the underlying mechanisms of CIH-induced vasculature injury and gender differences are not well documented. The iTRAQ Quantitative Proteomic method enables analysis of a number of different proteins among several groups. Thus, we explored gender differences in protein expression in the vascular walls of mice exposed to CIH. C57BL/6J mice of each gender were exposed to CIH with a fractional inspired O2 (FiO2) nadir of 5% or control, with a treatment time of 8 h/day for 28 days. Differential proteins related to CIH-induced vascular injury between genders were identified using iTRAQ proteomic technology. A total of 163 proteins were identified, of which 34 showed significant differences between genders, which may correlate with vascular injury by CIH. Twenty up-regulated proteins and 14 downregulated proteins were observed in female mice compared with male mice. We identified different vascular proteins expressed under CIH between genders, suggesting that these proteins may be biomarkers of vascular injury by CIH.
Assuntos
Aorta Abdominal/metabolismo , Hipóxia/metabolismo , Proteoma , Proteômica , Animais , Aorta Abdominal/lesões , Aorta Abdominal/patologia , Biologia Computacional , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Proteômica/métodos , Fatores Sexuais , Apneia Obstrutiva do Sono/metabolismoRESUMO
It has been described renal damage in rats with vascular calcification. The organic anion transporter 5 (Oat5) is only expressed in kidney, and its urinary excretion was proposed as potential early biomarker of renal injury. The aim of this study was to evaluate the Oat5 renal expression and its urinary excretion in an experimental model of vascular calcification in comparison with traditional markers of renal injury. Vascular calcification was obtained by the administration of an overdose of vitamin D3 (300,000 IU/kg, b.w., i.m.) to male Wistar rats. Oat5 urinary abundance was evaluated by Western blotting. Traditional markers of renal injury, such as creatinine and urea plasma levels, urinary protein levels, and urinary alkaline phosphatase (AP) activity, were determined using commercial kits. Histology was assessed by hematoxylin/eosin staining. Oat5 renal expression was evaluated by Western blotting and by immunohistochemistry. An increased expression of Oat5 in renal homogenates, in apical membranes, and in its urinary excretion was observed in rats with vascular calcification. The traditional parameters used to evaluate renal function were not modified, with the exception of histology. It is possible to postulate the urinary excretion of Oat5 as a potential noninvasive biomarker of renal injury associated with vascular calcification.
Assuntos
Transportadores de Ácidos Dicarboxílicos/metabolismo , Transportadores de Ácidos Dicarboxílicos/urina , Rim/metabolismo , Calcificação Vascular/urina , Fosfatase Alcalina/urina , Animais , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Aorta Abdominal/fisiopatologia , Pressão Sanguínea , Cálcio/metabolismo , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar , Sístole , Calcificação Vascular/patologia , Calcificação Vascular/fisiopatologiaRESUMO
BACKGROUND: Chronic allograft vasculopathy (CAV) is an important cause of graft loss. Considering the immune inflammatory events involved in the development of CAV, therapeutic approaches to target this process are of relevance. Human amniotic fluid-derived stem cells (hAFSCs), a class of fetal, pluripotent stem cells with intermediate characteristics between embryonic and adult stem cells, display immunomodulatory properties. hAFSCs express mesenchymal and embryonic markers, show high proliferation rates; however, they do not induce tumor formation, and their use does not raise ethical issues. Thus, we sought to investigate the effect of hAFSC on CAV in a model of aorta transplantation. METHODS: Orthotopic aorta transplantation was performed using Fisher (F344) rats as donors and Lewis rats as recipients. Rats were divided into three groups: syngeneic (SYNG), untreated F344 receiving aorta from F344 (n = 8); allogeneic (ALLO), Lewis rats receiving allogeneic aorta from F344 (n = 8); and ALLO + hAFSC, ALLO rats treated with hAFSC (10(6) cells; n = 8). Histological analysis and immunohistochemistry were performed 30 days posttransplantation. RESULTS: The ALLO group developed a robust aortic neointimal formation (208.7 ± 25.4 µm) accompanied by a significant high number of ED1+ (4845 ± 841 cells/mm2) and CD43+ cells (4064 ± 563 cells/mm2), and enhanced expression of α-smooth muscle actin in the neointima (25 ± 6%). Treatment with hAFSC diminished neointimal thickness (180.7 ± 23.7 µm) and induced a significant decrease of ED1+ (1100 ± 276 cells/mm2), CD43+ cells (1080 ± 309 cells/µm2), and α-smooth muscle actin expression 8 ± 3% in the neointima. CONCLUSIONS: These preliminary results showed that hAFSC suppressed inflammation and myofibroblast migration to the intima, which may contribute to ameliorate vascular changes in CAV.
Assuntos
Líquido Amniótico/citologia , Aorta Abdominal/transplante , Doenças da Aorta/prevenção & controle , Células-Tronco Fetais/transplante , Transplante de Órgãos/efeitos adversos , Células-Tronco Pluripotentes/transplante , Actinas/metabolismo , Animais , Aorta Abdominal/imunologia , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Doenças da Aorta/etiologia , Doenças da Aorta/imunologia , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Biomarcadores/metabolismo , Movimento Celular , Células Cultivadas , Células-Tronco Fetais/imunologia , Células-Tronco Fetais/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Neointima , Células-Tronco Pluripotentes/imunologia , Células-Tronco Pluripotentes/metabolismo , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Fatores de TempoRESUMO
BACKGROUND/AIMS: Calcium overload in vascular smooth muscle is a highly pathogenic event, which progresses with advancing age. Old patients are polymedicated, and several pharmacotherapeutic agents circulate in the plasma as organic anions. The organic anion transporters 1 and 3 (Oat1 and Oat3) are present in renal basolateral membranes, which transport organic anions of pharmacological and physiological interest. This study was designed to evaluate the renal expression and function of Oat1 and Oat3 in rats with vascular calcification. METHODS: Vascular calcification was induced by administration of a single dose of vitamin D(3) (300,000 UI/ kg b.w., i.m.) to male Wistar rats 10 days before the experiments. Oat1 and Oat3 expression was assessed by immunoblotting, immunohistochemistry and reverse-transcriptase polymerase chain reaction. The renal clearance of p-aminohippurate (PAH, a prototypical organic anion, substrate of Oat1 and Oat3) was measured by conventional clearance techniques. RESULTS: Oat1 and Oat3 protein levels showed an increase in plasma membranes of renal proximal tubules of treated animals, where both transporters are functional. This could explain the increase observed in the renal clearance of PAH in treated rats. CONCLUSIONS: These results suggest the relevance of considering the existence of vascular calcification, which is common in ageing, when organic anion drugs are prescribed.
Assuntos
Membrana Celular/metabolismo , Rim/fisiologia , Músculo Liso Vascular/fisiopatologia , Proteína 1 Transportadora de Ânions Orgânicos/fisiologia , Transportadores de Ânions Orgânicos Sódio-Independentes/fisiologia , Calcificação Vascular/fisiopatologia , Animais , Aorta Abdominal/metabolismo , Pressão Arterial , Cálcio/metabolismo , Colecalciferol , Modelos Animais de Doenças , Rim/patologia , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Calcificação Vascular/induzido quimicamente , Calcificação Vascular/metabolismo , Ácido p-Aminoipúrico/metabolismoRESUMO
BACKGROUND: The pathogenesis of abdominal aortic aneurysm is associated with changes of several components of arterial wall. Vascular glycosaminoglycans contribute to the non-thrombogenic activity of blood vessels. We investigated whether modifications of glycosaminoglycans in human abdominal aortic aneurysm affect their anticoagulant properties. METHODS: Glycosaminoglycans were extracted from abdominal aortic aneurysms (n=11) derived from reconstitution surgeries, human abdominal aortas (n=9) from normal organ transplant donors and from preserved (n=10) and atherosclerotic (n=17) segments obtained from autopsy of an old patient. Glycosaminoglycan composition, concentration and anticoagulant activity were determined. RESULTS: Glycosaminoglycans extracted from aneurysms have a more potent anticoagulant activity than those from normal arteries of young adults, mostly due to a relative enrichment of dermatan sulfate, which potentiates heparin cofactor II inhibition of thrombin. Arterial segments of aged patient with severe atherosclerosis showed a glycosaminoglycan composition similar to aneurysms samples. Glycosaminoglycans extracted from these regions showed also a more potent heparin cofactor II-dependent anticoagulant activity than lesion-free areas due to the relative enrichment of dermatan sulfate. CONCLUSION: The anticoagulant activity from abdominal aortic aneurysms is preserved. No modifications particular to the aneurysms were dissociated from those observed in atherosclerosis.
Assuntos
Aneurisma da Aorta Abdominal/metabolismo , Aterosclerose/metabolismo , Coagulação Sanguínea , Dermatan Sulfato/metabolismo , Heparitina Sulfato/metabolismo , Adolescente , Adulto , Idoso , Envelhecimento/metabolismo , Aorta Abdominal/metabolismo , Aorta Abdominal/fisiologia , Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/fisiopatologia , Aterosclerose/patologia , Aterosclerose/fisiopatologia , Humanos , Pessoa de Meia-Idade , Adulto JovemRESUMO
1 The role of the extraendothelial and constitutive isoforms of cyclo-oxygenase-2 (COX-2) in the contractile effect of angiotensin II (Ang II) was investigated using thoracic and abdominal aortic rings without endothelium from young Wistar rats. 2 Ang II elicited similar contractions in both aortic segments, and the effect was inhibited by pretreatment with NS398 (a selective COX-2 inhibitor) but not SC-560 [selective cyclo-oxygenase-1 (COX-1) inhibitor]. 3 COX-2 mRNA was expressed under basal conditions in both aortic segments. Additionally, Ang II increased COX-2 mRNA expression in the abdominal but not the thoracic segment, while cycloheximide (a protein synthesis inhibitor) did not affect the contractile response to Ang II in either of the two segments; this suggests that the effect is not associated with de novo COX-2 synthesis. 4 In conclusion, the basal amount of COX-2 found in aortic smooth muscle cells is sufficient to explain the production of the prostanoids related to the contractile effect of Ang II. The production of these prostanoids, which are derived from constitutive COX-2, occurs independently of the endothelium vascular system.
Assuntos
Angiotensina II/metabolismo , Aorta/metabolismo , Ciclo-Oxigenase 2/metabolismo , Endotélio Vascular/fisiologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Animais , Aorta/efeitos dos fármacos , Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/metabolismo , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Endotélio Vascular/efeitos dos fármacos , Técnicas In Vitro , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Especificidade de Órgãos , Concentração Osmolar , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Ratos , Ratos WistarRESUMO
Bradykinin (BK) is a vasorelaxant, algesic and inflammatory agent. Angiotensin II (AngII) is known to control vascular tone and promote growth, inflammation and artherogenesis. There is evidence for cross talking between BK and AngII receptors. Therefore, the effect of lack of kinin receptors was assessed in mice with genetic disruption of B(1) or B(2) and both receptors. Responsiveness of abdominal aortic rings to BK and AngII as well as the receptor gene expression of both peptides were analysed. Although no specific phenotype was displayed in the normotensive and healthy mice lacking the kinin receptors, a decreased expression level of the remaining kinin receptor mRNA was observed. AT(1) receptor mRNA level was also reduced, indicating that kinin receptors regulate AngII receptors. Downregulation of the receptors was well correlated with reduction in the reactivity of both agonists to induce contraction of aortic rings, but other signal regulations must be sought in these transgenic mice. We conclude that cross talk between kinin and AngII receptors occurs in mouse abdominal aorta and that both peptides may regulate the initiation and progression of important pathophysiological processes, such as hypertension and inflammation.