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1.
Nat Commun ; 10(1): 4223, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31530804

RESUMO

Diseases related to impaired blood flow such as peripheral artery disease (PAD) impact nearly 10 million people in the United States alone, yet patients with clinical manifestations of PAD (e.g., claudication and limb ischemia) have limited treatment options. In ischemic tissues, stress kinases such as c-Jun N-terminal kinases (JNKs), are activated. Here, we show that inhibition of the JNK3 (Mapk10) in the neural compartment strikingly potentiates blood flow recovery from mouse hindlimb ischemia. JNK3 deficiency leads to upregulation of growth factors such as Vegfa, Pdgfb, Pgf, Hbegf and Tgfb3 in ischemic muscle by activation of the transcription factors Egr1/Creb1. JNK3 acts through Forkhead box O3 (Foxo3a) to suppress the activity of Egr1/Creb1 transcription regulators in vitro. In JNK3-deficient cells, Foxo3a is suppressed which leads to Egr1/Creb1 activation and upregulation of downstream growth factors. Collectively, these data suggest that the JNK3-Foxo3a-Egr1/Creb1 axis coordinates the vascular remodeling response in peripheral ischemia.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Membro Posterior/irrigação sanguínea , Isquemia/metabolismo , Proteína Quinase 10 Ativada por Mitógeno/metabolismo , Neurônios/metabolismo , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Membro Posterior/inervação , Membro Posterior/metabolismo , Humanos , Isquemia/genética , Isquemia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 10 Ativada por Mitógeno/genética , Músculo Esquelético/metabolismo , Fluxo Sanguíneo Regional , Transdução de Sinais
2.
Int J Mol Sci ; 20(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540534

RESUMO

In recent years, mesenchymal stem cells (MSCs) have emerged as a promising therapeutic modality in regenerative medicine. They hold great promise for treating civilization-wide diseases, including cardiovascular diseases, such as acute myocardial infarction and critical limb ischemia. MSCs isolated from Wharton's jelly (WJ-MSCs) may be utilized in both cell-based therapy and vascular graft engineering to restore vascular function, thereby providing therapeutic benefits for patients. The efficacy of WJ-MSCs lies in their multipotent differentiation ability toward vascular smooth muscle cells, endothelial cells and other cell types, as well as their capacity to secrete various trophic factors, which are potent in promoting angiogenesis, inhibiting apoptosis and modulating immunoreaction. Ischemic limb disease is caused by insufficient nutrient and oxygen supplies resulting from damaged peripheral arteries. The lack of nutrients and oxygen causes severe tissue damage in the limb, thereby resulting in severe morbidities and mortality. The therapeutic effects of the conventional treatments are still not sufficient. Cell transplantations in small animal model (mice) are vital for deciphering the mechanisms of MSCs' action in muscle regeneration. The stimulation of angiogenesis is a promising strategy for the treatment of ischemic limbs, restoring blood supply for the ischemic region. In the present study, we focus on the therapeutic properties of the human WJ-MSCs derived product, Cardio. We investigated the role of CardioCell in promoting angiogenesis and relieving hindlimb ischemia. Our results confirm the healing effect of CardioCell and strongly support the use of the WJ-MSCs in regenerative medicine.


Assuntos
Membro Posterior/irrigação sanguínea , Isquemia/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Geleia de Wharton/citologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Camundongos , Camundongos SCID , Neovascularização Fisiológica , Regeneração
3.
Vasc Med ; 24(5): 395-404, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451089

RESUMO

Peripheral artery disease (PAD) is caused by atherosclerotic occlusions of vessels outside the heart, particularly those of the lower extremities. Angiogenesis is one critical physiological response to vessel occlusion in PAD, but our understanding of the molecular mechanisms involved in angiogenesis is incomplete. Dual specificity phosphatase 5 (DUSP5) has been shown to play a key role in embryonic vascular development, but its role in post-ischemic angiogenesis is not known. We induced hind limb ischemia in mice and found robust upregulation of Dusp5 expression in ischemic hind limbs. Moreover, in vivo knockdown of Dusp5 resulted in impaired perfusion recovery in ischemic limbs and was associated with increased limb necrosis. In vitro studies showed upregulation of DUSP5 in human endothelial cells exposed to ischemia, and knockdown of DUSP5 in these ischemic endothelial cells resulted in impaired endothelial cell proliferation and angiogenesis, but did not alter apoptosis. Finally, we show that these effects of DUSP5 on post-ischemic angiogenesis are a result of DUSP5-dependent decrease in ERK1/2 phosphorylation and p21 protein expression. Thus, we have identified a role of DUSP5 in post-ischemic angiogenesis and implicated a DUSP5-ERK-p21 pathway that may serve as a therapeutic target for the modulation of post-ischemic angiogenesis in PAD.


Assuntos
Fosfatases de Especificidade Dupla/metabolismo , Membro Posterior/irrigação sanguínea , Isquemia/enzimologia , Neovascularização Fisiológica , Doença Arterial Periférica/enzimologia , Animais , Linhagem Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Fosfatases de Especificidade Dupla/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Isquemia/genética , Isquemia/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Doença Arterial Periférica/genética , Doença Arterial Periférica/fisiopatologia , Fosforilação , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional , Transdução de Sinais
4.
Int J Mol Sci ; 20(15)2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31362356

RESUMO

Mouse hind limb ischemia is the most common used preclinical model for peripheral arterial disease and critical limb ischemia. This model is used to investigate the mechanisms of neovascularization and to develop new therapeutic agents. The literature shows many variations in the model, including the method of occlusion, the number of occlusions, and the position at which the occlusions are made to induce hind limb ischemia. Furthermore, predefined end points and the histopathological and radiological analysis vary. These differences hamper the correlation of results between different studies. In this review, variations in surgical methods of inducing hind limb ischemia in mice are described, and the consequences of these variations on perfusion restoration and vascular remodeling are discussed. This study aims at providing the reader with a comprehensive overview of the methods so far described, and proposing uniformity in research of hind limb ischemia in a mouse model.


Assuntos
Membro Posterior/irrigação sanguínea , Isquemia/diagnóstico , Isquemia/etiologia , Neovascularização Fisiológica , Complicações Pós-Operatórias , Procedimentos Cirúrgicos Operatórios , Animais , Modelos Animais de Doenças , Membro Posterior/anatomia & histologia , Membro Posterior/patologia , Membro Posterior/cirurgia , Camundongos , Imagem de Perfusão , Fluxo Sanguíneo Regional , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Procedimentos Cirúrgicos Operatórios/métodos , Ultrassonografia Doppler
5.
Opt Lett ; 44(15): 3773-3776, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31368965

RESUMO

Hypoxia, a low tissue oxygenation condition caused by insufficient oxygen supply, leads to potentially irreversible tissue damage, such as brain infarction during stroke. Intravascular oxygenation has long been used by photoacoustic imaging, among other imaging modalities, to study hypoxia. However, intravascular oxygenation describes only the oxygen supply via microcirculation, which does not directly reflect the amount of free oxygen available for metabolism in the interstitial fluid. Therefore, to fully understand hypoxia, it is highly desirable to monitor blood oxygenation as well as tissue oxygenation during the same biological process. In this work, by combining high-resolution photoacoustic microscopy (PAM) and a novel bioreducible N-oxide-based hypoxia-sensitive probe HyP-650, we have demonstrated simultaneous imaging of intravascular oxygenation and tissue hypoxia. We have established detailed chemical, optical, and photoacoustic properties of HyP-650 for hypoxic activation in vitro and in living cells. We have also performed PAM on hindlimb ischemia models and tumor-bearing mice to study the correlation between intravascular oxygenation and tissue oxygenation at various hypoxic levels. We expect that Hyp-650 enhanced photoacoustic imaging will find a variety of applications in brain and cancer research.


Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Vasos Sanguíneos/metabolismo , Oxigênio/metabolismo , Técnicas Fotoacústicas/métodos , Animais , Membro Posterior/irrigação sanguínea , Isquemia/metabolismo , Isquemia/patologia , Camundongos , Microscopia , Hipóxia Tumoral
6.
Analyst ; 144(15): 4677-4686, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31268052

RESUMO

We have investigated the development of murine hindlimb ischemia from day 1 to day 55 after femoral artery ligation (FAL) using blood flow analysis, functional tests, histopathological staining, and in vivo Raman spectroscopy. FAL resulted in hindlimb blood deprivation and the loss of functionality as attested by the blood flow analysis and functional tests, respectively. The limbs recovered a normal circulation progressively without recovering complete functionality. Histological analysis showed changes in the morphology of muscle fibers with intense inflammation. From day 22 to day 55 post-ischemia, regeneration of the myofibers was observed. Raman spectroscopic results related to subcutaneous analysis made the identification of modification in the biochemical constituents of hindlimb muscles possible during disease progression. Ischemia was characterized by a quantitative increase in the lipid content and a decrease in the protein content. The lipid to protein ratio can be used as a spectroscopic marker to score the severity of ischemia. Multivariate statistical analysis PC-LDA (Principal Component-Linear Discriminant Analysis) was used to classify all the data measured for the normal and ischemic tissues. This classification illustrated an excellent separation between the control and ischemic tissues at any time during the course of ischemic development. In vivo Raman spectroscopy was then applied to assess the potential of this technique as a screening tool to explore an ischemic disease non-invasively (transcutaneously). For this purpose, the influence of skin on the diagnostic accuracy was evaluated; transcutaneous analysis revealed the accuracy of this technique, indicating its potential in the in situ monitoring of muscle structural changes during ischemia.


Assuntos
Membro Posterior/metabolismo , Isquemia/diagnóstico , Isquemia/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Pele/metabolismo , Animais , Circulação Sanguínea/fisiologia , Análise Discriminante , Membro Posterior/irrigação sanguínea , Masculino , Camundongos Endogâmicos BALB C , Análise Multivariada , Fibras Musculares Esqueléticas/patologia , Análise Espectral Raman/métodos
7.
Int J Mol Sci ; 20(15)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344780

RESUMO

Collaterals are unique blood vessels present in the microcirculation of most tissues that, by cross-connecting a small fraction of the outer branches of adjacent arterial trees, provide alternate routes of perfusion. However, collaterals are especially susceptible to rarefaction caused by aging, other vascular risk factors, and mouse models of Alzheimer's disease-a vulnerability attributed to the disturbed hemodynamic environment in the watershed regions where they reside. We examined the hypothesis that endothelial and smooth muscle cells (ECs and SMCs, respectively) of collaterals have specializations, distinct from those of similarly-sized nearby distal-most arterioles (DMAs) that maintain collateral integrity despite their continuous exposure to low and oscillatory/disturbed shear stress, high wall stress, and low blood oxygen. Examination of mouse brain revealed the following: Unlike the pro-inflammatory cobble-stoned morphology of ECs exposed to low/oscillatory shear stress elsewhere in the vasculature, collateral ECs are aligned with the vessel axis. Primary cilia, which sense shear stress, are present, unexpectedly, on ECs of collaterals and DMAs but are less abundant on collaterals. Unlike DMAs, collaterals are continuously invested with SMCs, have increased expression of Pycard, Ki67, Pdgfb, Angpt2, Dll4, Ephrinb2, and eNOS, and maintain expression of Klf2/4. Collaterals lack tortuosity when first formed during development, but tortuosity becomes evident within days after birth, progresses through middle age, and then declines-results consistent with the concept that collateral wall cells have a higher turnover rate than DMAs that favors proliferative senescence and collateral rarefaction. In conclusion, endothelial and SMCs of collaterals have morphologic and functional differences from those of nearby similarly sized arterioles. Future studies are required to determine if they represent specializations that counterbalance the disturbed hemodynamic, pro-inflammatory, and pro-proliferative environment in which collaterals reside and thus mitigate their risk factor-induced rarefaction.


Assuntos
Vasos Sanguíneos/metabolismo , Circulação Colateral/genética , Miócitos de Músculo Liso/metabolismo , Neovascularização Fisiológica/genética , Envelhecimento/genética , Envelhecimento/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Vasos Sanguíneos/patologia , Circulação Colateral/fisiologia , Células Endoteliais/metabolismo , Artéria Femoral/crescimento & desenvolvimento , Artéria Femoral/metabolismo , Membro Posterior/irrigação sanguínea , Humanos , Camundongos , Fatores de Risco , Transdução de Sinais
8.
J Dairy Sci ; 102(10): 9213-9223, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31351728

RESUMO

Vascular changes play an important role in the pathogenesis of claw horn disruption lesions in cattle. The aim of the study was to measure arterial blood flow in the hind limbs of German Holstein cows with claw horn disruption lesions. A 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the dorsal pastern region in the hind limbs of 11 non-lame and 33 lame German Holstein cows in which lameness was scored clinically. Qualitative and quantitative blood flow parameters were compared in affected limbs and unaffected contralateral hind limbs in lame cows and in the hind limbs of lame cows and non-lame cows. A pulsed-wave Doppler signal suitable for analysis was obtained in 78 of 88 limbs (33 affected and contralateral limbs, 22 limbs of control cows). Blood flow curve types 1 and 2 were predominant in the hind limbs of lame cows. Vessel diameter, end-diastolic velocity, and blood flow rate were significantly greater in lame cows than in non-lame cows and were numerically greater in moderately lame cows than in mildly lame cows. The differences in the qualitative and quantitative parameters between lame and non-lame cows were most likely caused by inflammation of the pododerm. The role of weight distribution between the paired hind limbs and the existence of claw horn disruption appeared to have an effect on the differences in local circulation in the affected and unaffected contralateral hind limbs in lame cows.


Assuntos
Doenças dos Bovinos/fisiopatologia , Doenças do Pé/veterinária , Casco e Garras/irrigação sanguínea , Coxeadura Animal/fisiopatologia , Ultrassonografia Doppler/veterinária , Animais , Artérias , Bovinos , Feminino , Doenças do Pé/fisiopatologia , Membro Posterior/irrigação sanguínea , Fluxo Sanguíneo Regional
9.
Ann Vasc Surg ; 60: 455-462, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31200035

RESUMO

BACKGROUND: Temporary vascular shunts (TVSs) are an effective tool for rapidly restoring blood flow to a limb or organ that has experienced vascular injury and ischemia and for which revascularization is not an immediate option. Usually, through an opening in the skin, the TVS is positioned within the proximal and distal stumps of the injured vessel, restoring perfusion and stopping the ischemia. The aim of this study is to compare standard TVS technique and a developed puncture technique for implanting TVS and to evaluate the utility and feasibility of this protocol after arterial lesions, in pigs. METHODS: Vascular injuries were inflicted in both hind limbs of 30 pigs, and vascular interventions were performed, using standard and puncture TVS. Because each pig was implanted with both types of TVSs, it was possible to simultaneously monitor, analyze, and compare parameters such as, the mean arterial pressure (MAP, in mm Hg), blood flow (mL/min), and insertion times, in the same animal. RESULTS: It was observed that the MAP in the limbs recovered and approached systemic MAP, in 100% of the experiments, in both groups. Analysis of the blood flow data showed that this parameter was significantly reduced in the puncture TVS group (110.36 ± 9.99 mL/min vs. 153.20 ± 18.57 mL/min, P = 0.001). On the other hand, the insertion time for the standard TVS was significantly greater than that of the puncture shunt (15.32 ± 3.08 min vs. 10.37 ± 1.7 min, P = 0.001). Furthermore, it was found that the primary and secondary patency and complication rates were similar for both TVS types. CONCLUSION: Thus, given the adequate MAP recovery and reduction in implantation time observed in this experimental and in an animal model study, the use of the puncture TVS technique is effective and feasible.


Assuntos
Cateterismo Periférico/instrumentação , Artéria Femoral , Membro Posterior/irrigação sanguínea , Lesões do Sistema Vascular/terapia , Animais , Pressão Arterial , Velocidade do Fluxo Sanguíneo , Modelos Animais de Doenças , Estudos de Viabilidade , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/lesões , Artéria Femoral/fisiopatologia , Punções , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional , Sus scrofa , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/fisiopatologia
10.
Scand Cardiovasc J ; 53(4): 192-196, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31169413

RESUMO

Objectives. The hypothermic circulatory arrest (HCA) is still of paramount importance in aortic arch surgery, but the safe period of the arrest is limited. Remote ischaemic preconditioning (RIPC) prepares the cerebral tissue for ischaemic insult. Prolongation of the permissible period of HCA with RIPC may have a major impact on the outcome of aortic operations requiring cessation of blood flow by decreasing the rate of neurological deficits. Design. Twenty pigs were randomised into the RIPC group (n = 10) and the control group (n = 10). The RIPC group underwent four cycles of transient hind limb ischaemia. Both groups underwent cooling with cardiopulmonary bypass to 11 °C followed by a 45-minute HCA and re-warming to 36 °C. Cerebral blood flow was measured with a transit time ultrasonic flowmeter from the right common carotid artery, and the arteriovenous oxygen difference was calculated from sagittal sinus and arterial blood samples. Measurements were taken at several time points during cooling and warming. Temperature coefficient (Q10) was calculated to determine estimated permissible periods of HCA. Results. The Q10 was 2.27 (1.98-2.58) for the RIPC group and 1.87 (1.61-2.25) for the control group. The permissible period of HCA at 18 °C was 26 minutes (20-33) in the RIPC group and 17 minutes (13-25) in the control group (p = .063)(Data expressed in medians and interquartile ranges). Conclusions. RIPC tends to suppress cerebral metabolism during cooling with cardiopulmonary bypass and may prolong estimated permissible period of HCA.


Assuntos
Encéfalo/irrigação sanguínea , Parada Circulatória Induzida por Hipotermia Profunda , Membro Posterior/irrigação sanguínea , Hipóxia Encefálica/prevenção & controle , Precondicionamento Isquêmico/métodos , Traumatismo por Reperfusão/prevenção & controle , Animais , Velocidade do Fluxo Sanguíneo , Encéfalo/metabolismo , Circulação Cerebrovascular , Parada Circulatória Induzida por Hipotermia Profunda/efeitos adversos , Metabolismo Energético , Feminino , Hipóxia Encefálica/etiologia , Hipóxia Encefálica/metabolismo , Hipóxia Encefálica/fisiopatologia , Precondicionamento Isquêmico/efeitos adversos , Duração da Cirurgia , Fluxo Sanguíneo Regional , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Fatores de Risco , Sus scrofa , Fatores de Tempo
11.
Int Heart J ; 60(3): 736-745, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31105157

RESUMO

Aging is not only a major risk factor for impaired collateral growth under ischemia but also shortens the telomere length, which is regulated by telomerase. We examined the role of telomerase activity during impaired collateral growth during aging in ischemic skeletal muscle. Unilateral hind limb ischemia was generated in old, young, and old mice chronically administered a telomerase activator. In old mice, blood flow recovery and capillary density development in ischemic hind limbs were reduced compared to those in young mice, and these changes were restored to equal levels by administration of TA-65, a telomerase activator. During the early phase of ischemic muscle changes in old mice, telomerase reverse transcriptase expression and telomerase activity were both low compared to those in young mice and old mice treated with TA-65. Levels of reactive oxygen species (ROS), DNA double-strand breaks, and expression of p53, p16, and Bax/Bcl-2 were all elevated in ischemic muscles of old mice compared to those in the muscles of young mice and old mice treated with TA-65 treatment; these factors were maintained at low levels equivalent to those seen in young mice during the experiment. Expression of HIF1α/vascular endothelial growth factor (VEGF) and PGC1α were decreased in old mice compared to those in young mice and old mice treated with TA-65. Collateral growth under ischemic conditions is impaired in aged animals due to low telomerase activity, increased ROS, resultant DNA damage, and expression of tumor suppressor and pro-apoptotic proteins. These data suggest that telomerase activation enhances collateral growth and rescues ischemic tissue in old individuals.


Assuntos
Envelhecimento/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Isquemia/metabolismo , Telomerase/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica , Membro Posterior/irrigação sanguínea , Isquemia/induzido quimicamente , Camundongos , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Fluxo Sanguíneo Regional
12.
Am J Physiol Endocrinol Metab ; 317(2): E244-E249, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31112407

RESUMO

It is unknown whether activation of hepato-portal vein (PV) glucose sensors plays a role in incretin hormone amplification of oral glucose-stimulated insulin secretion (GSIS). In previous studies, PV glucose infusion increased GSIS through unknown mechanisms, perhaps neural stimulation of pancreatic ß-cells and/or stimulation of gut incretin hormone release. Thus, there could be a difference in the incretin effect when comparing GSIS with portal rather than leg vein (LV) glucose infusion. Plasma insulin and incretin hormones were studied in six overnight-fasted dogs. An oral glucose tolerance test (OGTT) was administered, and then 1 and 2 wk later the arterial plasma glucose profile from the OGTT was mimicked by infusing glucose into either the PV or a LV. The arterial glucose levels were nearly identical between groups (AUCs within 1% of each other). Oral glucose administration increased arterial GLP-1 and GIP levels by more than sixfold, whereas they were not elevated by PV or LV glucose infusion. Oral glucose delivery was associated with only a small incretin effect (arterial insulin and C-peptide were 21 ± 23 and 24 ± 17% greater, respectively, during the 1st hour with oral compared with PV glucose and 14 ± 37 and 13 ± 35% greater, respectively, in oral versus LV; PV versus LV responses were not significantly different from each other). Thus, following an OGTT incretin hormone release did not depend on activation of PV glucose sensors, and the insulin response was not greater with PV compared with LV glucose infusion in the dog. The small incretin effect points to species peculiarities, which is perhaps related to diet.


Assuntos
Glucose/farmacologia , Incretinas/metabolismo , Veia Porta/metabolismo , Animais , Glicemia/análise , Peptídeo C/sangue , Cães , Feminino , Polipeptídeo Inibidor Gástrico/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Glucose/administração & dosagem , Teste de Tolerância a Glucose , Membro Posterior/irrigação sanguínea , Infusões Intravenosas , Insulina/sangue , Insulina/metabolismo , Masculino , Veia Porta/química , Fluxo Sanguíneo Regional , Veias
13.
J Vasc Interv Radiol ; 30(6): 949-955, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30935867

RESUMO

PURPOSE: To determine whether nylon fibers improve the performance of platinum embolization coils in porcine arteries. MATERIALS AND METHODS: Platinum 0.035" embolization coils, both with and without nylon fibers, were used to embolize a total of 24 hindlimb arteries in 6 swine: 12 with fibered coils and 12 with non-fibered coils. Apart from fibers, the coils were identical. Immediate and late results were studied, including number of coils needed to achieve vessel occlusion and durability of occlusion at 1 and 3 months. Arteriographic as well as histopathologic analysis were performed. RESULTS: A mean of 3.2 (range, 2-4) non-fibered coils was required to achieve occlusion, whereas a mean of 1.3 (range, 1-2) fibered coils achieved occlusion in similarly sized arteries (2.3-3.2-mm diameter, P < .001). The mean percent cross-sectional area occupied by thrombus was greater in arteries with fibered coils than with non-fibered coils at 1 month (63% ± 6% and 48% ± 15%, respectively, P = .03) but not at 3 months (61% ± 6% and 49% ± 15%, respectively, P = .06). Some recanalization was observed at follow-up and did not differ between groups at 1 month (P = .07) or 3 months (P = .22). CONCLUSIONS: Nylon fibers allow significantly fewer embolization coils to achieve acute occlusion of arteries compared to bare metal coils. Both fibered and non-fibered coils showed recanalization at follow-up.


Assuntos
Artérias , Materiais Revestidos Biocompatíveis , Embolização Terapêutica/instrumentação , Membro Posterior/irrigação sanguínea , Nylons , Platina , Animais , Artérias/diagnóstico por imagem , Artérias/patologia , Embolização Terapêutica/efeitos adversos , Desenho de Equipamento , Feminino , Modelos Animais , Sus scrofa , Trombose/diagnóstico por imagem , Trombose/patologia , Fatores de Tempo
14.
J Orthop Surg Res ; 14(1): 95, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30947735

RESUMO

BACKGROUND: Nitrogen-containing bisphosphonates (BIS) are potent therapeutics in osteoporosis, but their use may result in osteonecrotic side-effects in the maxillofacial region. Periosteal microcirculatory reactions may contribute to the development of bone-healing complications, particularly in osteoporotic bones, where ischemia-reperfusion (IR) events often develop during orthopaedic/trauma interventions. The effect of BIS on the inflammatory reactions of appendicular long bones has not yet been evaluated; thus, we aimed to examine the influence of chronic zoledronate (ZOL) administration on the periosteal microcirculatory consequences of hindlimb IR in osteopenic rats. MATERIALS AND METHODS: Twelve-week-old female Sprague-Dawley rats were ovariectomized (OVX) or sham-operated, and ZOL (80 µg/kg iv, weekly) or a vehicle was administered for 8 weeks, 4 weeks after the operation. At the end of the pre-treatment protocols, 60-min limb ischemia was induced, followed by 180-min reperfusion. Leukocyte-endothelial interactions were quantitated in tibial periosteal postcapillary venules by intravital fluorescence videomicroscopy. CD11b expression of circulating polymorphonuclear leukocytes (PMN, flow cytometry) and plasma TNF-alpha levels (ELISA) were also determined. Two-way RM ANOVA followed by the Holm-Sidak and Dunn tests was used to assess differences within and between groups, respectively. RESULTS: Limb IR induced significant increases in PMN rolling and firm adhesion in sham-operated and OVX rats, which were exacerbated temporarily in the first 60 min of reperfusion by a ZOL treatment regimen. Postischemic TNF-alpha values showed a similar level of postischemic elevations in all groups, whereas CD11b expression only increased in rats not treated with ZOL. CONCLUSIONS: The present data do not show substantial postischemic periosteal microcirculatory complications after chronic ZOL treatment either in sham-operated or OVX rats. The unaltered extent of limb IR-induced local periosteal microcirculatory reactions in the presence of reduced CD11b adhesion molecule expression on circulating PMNs, however, may be attributable to local endothelial injury/activation caused by ZOL.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Membro Posterior/irrigação sanguínea , Microcirculação/efeitos dos fármacos , Traumatismo por Reperfusão/fisiopatologia , Ácido Zoledrônico/farmacologia , Animais , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/tratamento farmacológico , Antígeno CD11b/sangue , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Feminino , Neutrófilos/efeitos dos fármacos , Neutrófilos/fisiologia , Ovariectomia , Periósteo/irrigação sanguínea , Periósteo/efeitos dos fármacos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/sangue
15.
Int J Oncol ; 54(4): 1327-1336, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30968151

RESUMO

Endothelial progenitor cells (EPCs) are bone marrow (BM)­derived progenitor cells that can differentiate into mature endothelial cells, contributing to vasculogenesis in the blood vessel formation process. Runt­related transcription factor 3 (RUNX3) belongs to the Runt domain family and is required for the differentiation of specific immune cells and neurons. The tumor suppressive role of RUNX3, via the induction of apoptosis and cell cycle arrest in a variety of cancers, and its deletion or frequent silencing by epigenetic mechanisms have been studied extensively; however, its role in the differentiation of EPCs is yet to be investigated. Therefore, in the present study, adult BM­derived hematopoietic stem cells (HSCs) were isolated from Runx3 heterozygous (Rx3+/­) or wild­type (WT) mice. The differentiation of EPCs from the BM­derived HSCs of Rx3+/­ mice was found to be significantly increased compared with those of the WT mice, as determined by the number of small or large colony­forming units. The migration and tube formation abilities of Rx3+/­ EPCs were also observed to be significantly increased compared with those of WT EPCs. Furthermore, the number of circulating EPCs, defined as CD34+/vascular endothelial growth factor receptor 2 (VEGFR2)+ cells, was also significantly increased in Rx3+/­ mice. Hypoxia­inducible factor (HIF)­1α was upregulated in Rx3+/­ EPCs compared with WT EPCs, even under normoxic conditions. Furthermore, in a hindlimb ischemic mouse models, the recovery of blood flow was observed to be highly stimulated in Rx3+/­ mice compared with WT mice. Also, in a Lewis lung carcinoma cell allograft model, the tumor size in Rx3+/­ mice was significantly larger than that in WT mice, and the EPC cell population (CD34+/VEGFR2+ cells) recruited to the tumor was greater in the Rx3+/­ mice compared with the WT mice. In conclusion, the present study revealed that Runx3 inhibits vasculogenesis via the inhibition of EPC differentiation and functions via the suppression of HIF­1α activity.


Assuntos
Carcinoma Pulmonar de Lewis/patologia , Diferenciação Celular/fisiologia , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Células Progenitoras Endoteliais/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Animais , Vasos Sanguíneos/crescimento & desenvolvimento , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Membro Posterior/irrigação sanguínea , Humanos , Isquemia/patologia , Masculino , Camundongos , Camundongos Transgênicos , Neovascularização Patológica/patologia , Cultura Primária de Células , Regulação para Cima
16.
J Surg Res ; 241: 240-246, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31035138

RESUMO

BACKGROUND: Designing peripheral arterial stents has proved challenging, as implanted devices will repetitively and unpredictably deform and fatigue during movement. Preclinical testing is often inadequate, given the lack of relevant animal models. The purpose of this study was to test the hypothesis that deformation of the human peripheral vasculature could be qualitatively and quantitatively modeled using an experimental animal. METHODS: Anteroposterior contrast angiography was performed in domestic Landrace-Yorkshire farm pigs. Images were obtained with the hind limbs naturally extended then repeated, (1) flexed approximately 90° at the hip and knee, (2) overflexed in a nonphysiological fashion. Quantitative vascular angiographic analysis was utilized to measure arterial diameter, length, and deformation. Percent axial arterial compression and bending were assessed. RESULTS: Eight iliofemoral arteries in four animals were imaged. Mean luminal diameters of the iliac and femoral segments in the neutral position were 5.4 ± 0.5 mm and 4.6 ± 0.5 mm. Hind limb physiologic flexion induced profound arterial compression, 17 ± 8% and 29 ± 6% and bending, 36°±10° and 76° ± 13° within the iliac and femoral segments, respectively. With extreme flexion, the femoral artery could be reliably bent >90°. The observed findings exceeded the deformation observed historically within the human superficial femoral (∼5% compression and 10° bending) and popliteal artery (∼10% compression and 70° bending). CONCLUSIONS: Significant nonradial deformation of the porcine iliofemoral arteries was observed during manual hind limb flexion and exceeded that typically observed in humans. This model constitutes a "worst case" scenario for testing deformation and fatigue of intravascular devices indicated for the human peripheral vasculature.


Assuntos
Artéria Femoral/fisiologia , Teste de Materiais/métodos , Artéria Poplítea/fisiologia , Desenho de Prótese , Falha de Prótese , Angiografia , Animais , Fenômenos Biomecânicos , Meios de Contraste/administração & dosagem , Procedimentos Endovasculares/instrumentação , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Membro Posterior/irrigação sanguínea , Membro Posterior/fisiologia , Humanos , Masculino , Modelos Animais , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Amplitude de Movimento Articular/fisiologia , Stents , Estresse Mecânico , Sus scrofa , Doenças Vasculares/cirurgia
17.
Kaohsiung J Med Sci ; 35(7): 417-424, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30977589

RESUMO

Limb ischemia reperfusion (LIR) can activate endogenous cytoprotective mechanisms by generating specific proteins against reperfusion injury in remote organs. The present study investigated the roles of heme oxygenase-1 (HO-1) pathway and the molecular mechanisms underlying the regulation of this pathway on lung injury following LIR. LIR was induced by ischemia for 4 hours followed by reperfusion for 6 hours (LIR 6 hours) or 16 hours (LIR 16 hours) in male Sprague-Dawley rats. HO-1 inducer cobalt protoporphyrin (Copp) or HO-1 inhibitor zinc protoporphyrin (Znpp) was intravenously injected 24 hours before ischemia. The animals were randomly divided into nine groups, including normal control, LIR 6 hours, LIR 16 hours, Copp, Copp + LIR 6 hours, Copp + LIR 16 hours, and Znpp, Znpp+ LIR 6 hours, and Znpp + LIR 16 hours groups (each group included four samples). Lung injury was examined through histopathology. Quantitative real-time PCR, immunohistochemistry and Western blot were applied to detect the mRNA and protein levels of HO-1, Nrf2, and Bach1. Our study showed that LIR induced Nrf2 upregulation but Bach1 downregulation to promote HO-1 expression in lung tissues. Activation of HO-1 pathway by Copp potentially enhanced Nrf2 expression but inhibition of the pathway by Znpp promoted Bach1 expression. Inducer of HO-1 pathway, Copp injection improved the lung injury. Nevertheless, Znpp injection aggravated the lung injury following LIR. Our findings suggested that activated HO-1 pathway might exert protective effects on the lung injury following LIR.


Assuntos
Heme Oxigenase (Desciclizante)/genética , Lesão Pulmonar/genética , Traumatismo por Reperfusão/genética , Transdução de Sinais/genética , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Ativadores de Enzimas/farmacologia , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica , Heme Oxigenase (Desciclizante)/antagonistas & inibidores , Heme Oxigenase (Desciclizante)/metabolismo , Membro Posterior/irrigação sanguínea , Membro Posterior/efeitos dos fármacos , Membro Posterior/enzimologia , Pulmão , Lesão Pulmonar/etiologia , Lesão Pulmonar/patologia , Lesão Pulmonar/prevenção & controle , Masculino , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Protoporfirinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle
18.
Mater Sci Eng C Mater Biol Appl ; 99: 322-332, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889706

RESUMO

Vascular disease is a major complication of aging, but the molecular mechanisms underlying the aging-induced vascular dysfunction remain unclear, and there is no effective treatment to prevent aging induced diseases. The objectives of the present study are to identify the signaling pathway mediating aging-induced vascular dysfunction and to develop an exosome based therapy to inhibit aging process. We used 11-month-old C57BL6 mice as pre-aging animal model and H2O2 treated H9C2 cells as an in vitro aging model to examine the therapeutic effect of miR-675. We found decreased expression of the potential aging modulator miR-675 in aging muscle, and H2O2 treatment decreased the expression of miR-675 and upregulated the expression of the aging marker ß-gal and TGF-ß1. We also found that miR-675 mimic decreased ß-gal staining in H2O2 treated H9C2 cells. Dual-luciferase reporter assays verified TGF-ß1 as the target gene of miR-675. Moreover, senescent H9C2 cells incubated with exosomes isolated from UMSCs transfected with the miR-675 mimic showed increased expression of miR-675, reduced activity of the aging marker ß-gal and reduced protein levels of TGF-ß1. We employed silk fibroin hydrogel to encapsulate exosomes in order to prolong the half-life of exosome in vivo. Fourier transform infrared spectroscopy (FTIR) revealed that exosomes were successfully encapsulated by the hydrogel. Laser Doppler perfusion imaging showed that the miR-675 exosomes encapsulated in silk fibroin hydrogel promote blood perfusion in ischemic hindlimbs. We demonstrated that miR-675 exosomes encapsulated in silk fibroin hydrogel provided sustained release of exosomes in vitro, and increased the retention time of red fluorescent PKH26-exosome in the tissue. Taken together, this study identified miR-675 as an important regulator of cell senescence and provided a novel strategy to deliver powerful exosomes by silk fibroin hydrogel to treat aging-induced vascular dysfunction.


Assuntos
Envelhecimento/patologia , Exossomos/metabolismo , Fibroínas/química , Técnicas de Transferência de Genes , Membro Posterior/fisiopatologia , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Animais , Sequência de Bases , Bombyx , Forma Celular , Senescência Celular , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Membro Posterior/irrigação sanguínea , Humanos , Camundongos , MicroRNAs/genética , Perfusão , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Cordão Umbilical/citologia
19.
Mol Med Rep ; 19(4): 3321-3329, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30816501

RESUMO

Cuscuta chinensis Lamak (CCL) has traditionally been used in Korea to treat sexual disorders and skin problems. The aim of the present study was to investigate the effects of CCL extract on surgical injury­induced ischemia in the hind limbs of mice. Specifically, female C57BL/6 mice were ovariectomized, and their hind­limb vessels were ligated with surgical silk (6­0) and excised. CCL (150 or 450 mg/kg/BW) was then administered to the mice for 3 weeks, and the blood flow rate was evaluated using a laser Doppler system at ­7, 0, 7, 14 and 21 days following hind­limb ischemia. The serum expression profiles of angiogenic and inflammatory mediators were measured using an antibody array, and the transcript levels were reverse transcription­quantitative polymerase chain reaction. The rate of hind limb blood flow was normalized to non­ischemic lesions and revealed to be markedly elevated at 14 and 21 days following ischemia when compared with the vehicle group. The density of capillaries in the hind limbs was also significantly increased following treatment with CCL in a dose­dependent manner. In addition, the transcriptional expression of angiogenetic factors were upregulated, whereas that of inflammatory cytokines were downregulated. Finally, vascular endothelial cell migration and tube formation were evaluated in vitro using human umbilical vein endothelial cells (HUVECs) and identified to be significantly increased following treatment with CCL. Overall, the results of the present study indicate that CCL extract exhibits therapeutic potential for the treatment of hind­limb ischemia as it promotes peripheral angiogenic and anti­inflammatory effects in mice.


Assuntos
Indutores da Angiogênese/farmacologia , Anti-Inflamatórios/farmacologia , Cuscuta/química , Membro Posterior/irrigação sanguínea , Membro Posterior/patologia , Isquemia/patologia , Extratos Vegetais/farmacologia , Indutores da Angiogênese/química , Animais , Anti-Inflamatórios/química , Biomarcadores , Movimento Celular/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Expressão Gênica , Membro Posterior/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Isquemia/tratamento farmacológico , Isquemia/etiologia , Camundongos , Extratos Vegetais/química , Cicatrização/efeitos dos fármacos
20.
Redox Biol ; 22: 101143, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30897521

RESUMO

First described as essential to the phagocytic activity of leukocytes, Nox2-derived ROS have emerged as mediators of a range of cellular and tissue responses across species from salubrious to deleterious consequences. Knowledge of their role in inflammation is limited, however. We postulated that TNFα-induced endothelial reactive oxygen species (ROS) generation and pro-inflammatory signaling would be ameliorated by targeting Nox2. Herein, we in silico-modelled two first-in-class Nox2 inhibitors developed in our laboratory, explored their cellular mechanism of action and tested their efficacy in in vitro and mouse in vivo models of inflammation. Our data show that these inhibitors (CPP11G and CPP11H) disrupted canonical Nox2 organizing factor, p47phox, translocation to Nox2 in the plasma membrane; and abolished ROS production, markedly attenuated stress-responsive MAPK signaling and downstream AP-1 and NFκB nuclear translocation in human cells. Consequently, cell adhesion molecule expression and monocyte adherence were significantly inhibited by both inhibitors. In vivo, TNFα-induced ROS and inflammation were ameliorated by targeted Nox2 inhibition, which, in turn, improved hind-limb blood flow. These studies identify a proximal role for Nox2 in propagated inflammatory signaling and support therapeutic value of Nox2 inhibitors in inflammatory disease.


Assuntos
Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Inibidores Enzimáticos/farmacologia , Membro Posterior/irrigação sanguínea , Membro Posterior/metabolismo , NADPH Oxidase 2/antagonistas & inibidores , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasculite/metabolismo , Animais , Biomarcadores , Adesão Celular , Linhagem Celular , Inibidores Enzimáticos/química , Humanos , Camundongos , Modelos Moleculares , Conformação Molecular , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , NADPH Oxidase 2/química , NADPH Oxidase 2/metabolismo , NF-kappa B/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Relação Estrutura-Atividade , Fator de Transcrição AP-1/metabolismo , Vasculite/tratamento farmacológico , Vasculite/etiologia , Vasculite/patologia
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