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1.
Life Sci ; 284: 119934, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34508762

RESUMO

AIMS: The purpose of this study was to investigate the effect of PPRP (pure PRP) and LPRP (PRP with leukocytes) on recovery from limb ischemia and on expression of growth factors involved in angiogenesis, myogenesis and fibrogenesis. MATERIAL AND METHODS: PPRP and LPRP prepared by centrifugation were added to cultures of C2C12 and NIH3T3 cells (1 or 10% PRPs) to evaluate alterations in cell metabolism and expression of growth factors by MTT, ELISA and RT-qPCR, respectively. To evaluate in vivo regenerative effects, PRPs were injected into the ischemic limbs of BALB/c mice and muscle mass/strength and histomorphometry were evaluated after 30 days. KEY FINDINGS: Mice treated with PRPs after limb ischemia showed an increase in the size of myofibers and muscle strength, reduced fibrosis and adipocytes, and decreased capillary density and necrosis scores compared to untreated mice. In cell culture, serum deprivation reduced the viability of C2C12 and NIH3T3 cells to about 50%, but the addition of 1% PRPs completely recovered this loss. Both PRPs, downregulated most of the tested genes; however, angiogenic gene Vegfa in C2C12 and the fibrogenic genes Col1a1 and Col3a1 in NIH3T3 cells were upregulated by LPRP. SIGNIFICANCE: PPRP and LPRP had similar effects in regulation of genes involved in angiogenesis, myogenesis and fibrogenesis. However, the presence of leucocytes did not significantly affect regenerative activities of PRP in the ischemic limb.


Assuntos
Membro Posterior/fisiopatologia , Isquemia/fisiopatologia , Plasma Rico em Plaquetas/metabolismo , Regeneração/fisiologia , Animais , Sobrevivência Celular , Regulação da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/patologia , Células NIH 3T3
2.
Arterioscler Thromb Vasc Biol ; 41(9): 2469-2482, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34320834

RESUMO

Objective: Critical limb ischemia is a major complication of diabetes characterized by insufficient collateral vessel development and proper growth factor signaling unresponsiveness. Although mainly deactivated by hypoxia, phosphatases are important players in the deregulation of proangiogenetic pathways. Previously, SHP-1 (Scr homology 2-containing phosphatase-1) was found to be associated with the downregulation of growth factor actions in the diabetic muscle. Thus, we aimed to gain further understanding of the impact of SHP-1 on smooth muscle cell (SMC) function under hypoxic and diabetic conditions. Approach and Results: Despite being inactivated under hypoxic conditions, high glucose level exposure sustained SHP-1 phosphatase activity in SMC and increased its interaction with PDGFR (platelet-derived growth factor receptor)-ß, thus reducing PDGF proangiogenic actions. Overexpression of an inactive form of SHP-1 fully restored PDGF-induced proliferation, migration, and signaling pathways in SMC exposed to high glucose and hypoxia. Nondiabetic and diabetic mice with deletion of SHP-1 specifically in SMC were generated. Ligation of the femoral artery was performed, and blood flow was measured for 4 weeks. Blood flow reperfusion, vascular density and maturation, and limb survival were all improved while vascular apoptosis was attenuated in diabetic SMC-specific SHP-1 null mice as compared to diabetic mice. Conclusions: Diabetes and high glucose level exposure maintained SHP-1 activity preventing hypoxia-induced PDGF actions in SMC. Specific deletion of SHP-1 in SMC partially restored blood flow reperfusion in the diabetic ischemic limb. Therefore, local modulation of SHP-1 activity in SMC could represent a potential therapeutic avenue to improve the proangiogenic properties of SMC under ischemia and diabetes.


Assuntos
Indutores da Angiogênese/farmacologia , Diabetes Mellitus Experimental/enzimologia , Angiopatias Diabéticas/enzimologia , Membro Posterior/irrigação sanguínea , Isquemia/enzimologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Animais , Glicemia/metabolismo , Estudos de Casos e Controles , Bovinos , Hipóxia Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/fisiopatologia , Angiopatias Diabéticas/genética , Angiopatias Diabéticas/fisiopatologia , Ativação Enzimática , Humanos , Isquemia/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Transdução de Sinais
3.
Pediatr Rheumatol Online J ; 19(1): 104, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193201

RESUMO

BACKGROUND: H syndrome (HS) is a rare autoinflammatory disease caused by a mutation in the solute carrier family 29, member 3 (SCL29A3) gene. It has a variable clinical presentation and little phenotype-genotype correlation. The pathognomonic sign of HS is cutaneous hyperpigmentation located mainly in the inner thighs and often accompanied by other systemic manifestations. Improvement after tocilizumab treatment has been reported in a few patients with HS. We report the first patient with HS who presented cardiogenic shock, multiorgan infiltration, and digital ischemia. CASE PRESENTATION: 8-year-old boy born to consanguineous parents of Moroccan origin who was admitted to the intensive care unit during the Coronavirus Disease-2019 (COVID-19) pandemic with tachypnoea, tachycardia, and oliguria. Echocardiography showed dilated cardiomyopathy and severe systolic dysfunction compatible with cardiogenic shock. Additionally, he presented with multiple organ dysfunction syndrome. SARS-CoV-2 polymerase chain reaction (PCR) and antibody detection by chromatographic immunoassay were negative. A previously ordered gene panel for pre-existing sensorineural hearing loss showed a pathological mutation in the SCL29A3 gene compatible with H syndrome. Computed tomography scan revealed extensive alveolar infiltrates in the lungs and multiple poor defined hypodense lesions in liver, spleen, and kidneys; adenopathy; and cardiomegaly with left ventricle subendocardial nodules. Invasive mechanical ventilation, broad antibiotic and antifungal coverage showed no significant response. Therefore, Tocilizumab as compassionate use together with pulsed intravenous methylprednisolone was initiated. Improvement was impressive leading to normalization of inflammation markers, liver and kidney function, and stabilising heart function. Two weeks later, he was discharged and has been clinically well since then on two weekly administration of Tocilizumab. CONCLUSIONS: We report the most severe disease course produced by HS described so far in the literature. Our patient's manifestations included uncommon, new complications such as acute heart failure with severe systolic dysfunction, multi-organ cell infiltrate, and digital ischemia. Most of the clinical symptoms of our patient could have been explained by SARS-CoV-2, demonstrating the importance of a detailed differential diagnosis to ensure optimal treatment. Although the mechanism of autoinflammation of HS remains uncertain, the good response of our patient to Tocilizumab makes a case for the important role of IL-6 in this syndrome and for considering Tocilizumab as a first-line treatment, at least in severely affected patients.


Assuntos
Cardiomiopatia Dilatada/fisiopatologia , Doenças Hereditárias Autoinflamatórias/fisiopatologia , Isquemia/fisiopatologia , Insuficiência de Múltiplos Órgãos/fisiopatologia , Choque Cardiogênico/fisiopatologia , Anticorpos Monoclonais Humanizados/uso terapêutico , COVID-19 , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/terapia , Criança , Glucocorticoides/uso terapêutico , Doenças Hereditárias Autoinflamatórias/diagnóstico , Doenças Hereditárias Autoinflamatórias/genética , Doenças Hereditárias Autoinflamatórias/terapia , Humanos , Isquemia/terapia , Nefropatias/diagnóstico por imagem , Nefropatias/fisiopatologia , Nefropatias/terapia , Hepatopatias/diagnóstico por imagem , Hepatopatias/fisiopatologia , Hepatopatias/terapia , Pneumopatias/diagnóstico por imagem , Pneumopatias/fisiopatologia , Pneumopatias/terapia , Linfadenopatia/diagnóstico por imagem , Linfadenopatia/fisiopatologia , Linfadenopatia/terapia , Masculino , Metilprednisolona/uso terapêutico , Insuficiência de Múltiplos Órgãos/terapia , Proteínas de Transporte de Nucleosídeos/genética , Pulsoterapia , Respiração Artificial , SARS-CoV-2 , Choque Cardiogênico/terapia , Esplenopatias/diagnóstico por imagem , Esplenopatias/fisiopatologia , Esplenopatias/terapia , Dedos do Pé/irrigação sanguínea , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
Am J Physiol Regul Integr Comp Physiol ; 321(3): R385-R395, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34259041

RESUMO

Exercise intolerance is a hallmark symptom of cardiovascular disease and likely occurs via enhanced activation of muscle metaboreflex-induced vasoconstriction of the heart and active skeletal muscle which, thereby limits cardiac output and peripheral blood flow. Muscle metaboreflex vasoconstrictor responses occur via activation of metabolite-sensitive afferent fibers located in ischemic active skeletal muscle, some of which express transient receptor potential vanilloid 1 (TRPV1) cation channels. Local cardiac and intrathecal administration of an ultrapotent noncompetitive, dominant negative agonist resiniferatoxin (RTX) can ablate these TRPV1-sensitive afferents. This technique has been used to attenuate cardiac sympathetic afferents and nociceptive pain. We investigated whether intrathecal administration (L4-L6) of RTX (2 µg/kg) could chronically attenuate subsequent muscle metaboreflex responses elicited by reductions in hindlimb blood flow during mild exercise (3.2 km/h) in chronically instrumented conscious canines. RTX significantly attenuated metaboreflex-induced increases in mean arterial pressure (27 ± 5.0 mmHg vs. 6 ± 8.2 mmHg), cardiac output (1.40 ± 0.2 L/min vs. 0.28 ± 0.1 L/min), and stroke work (2.27 ± 0.2 L·mmHg vs. 1.01 ± 0.2 L·mmHg). Effects were maintained until 78 ± 14 days post-RTX at which point the efficacy of RTX injection was tested by intra-arterial administration of capsaicin (20 µg/kg). A significant reduction in the mean arterial pressure response (+45.7 ± 6.5 mmHg pre-RTX vs. +19.7 ± 3.1 mmHg post-RTX) was observed. We conclude that intrathecal administration of RTX can chronically attenuate the muscle metaboreflex and could potentially alleviate enhanced sympatho-activation observed in cardiovascular disease states.


Assuntos
Débito Cardíaco/efeitos dos fármacos , Diterpenos/farmacologia , Membro Posterior/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Animais , Pressão Arterial/efeitos dos fármacos , Débito Cardíaco/fisiologia , Diterpenos/administração & dosagem , Cães , Coração/efeitos dos fármacos , Coração/fisiopatologia , Membro Posterior/fisiopatologia , Isquemia/fisiopatologia , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Vasoconstrição/fisiologia
5.
Eur J Vasc Endovasc Surg ; 62(3): 463-468, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34303599

RESUMO

OBJECTIVE: Acute peripheral arterial occlusions can be treated by catheter directed thrombolysis (CDT). However, CDT is time consuming and accompanied by the risk of bleeding complications. The addition of contrast enhanced ultrasound and microbubbles could improve thrombus susceptibility to thrombolytic agents and potentially shorten treatment time with a lowered risk of bleeding complications. This article reports the outcomes of the safety and feasibility of this novel technique. METHODS: In this single arm phase II trial, 20 patients with acute lower limb ischaemia received CDT combined with an intravenous infusion of microbubbles and locally applied ultrasound during the first hour of standard intra-arterial thrombolytic therapy. The primary endpoint was safety, i.e., occurrence of serious adverse events (haemorrhagic complications and/or amputation) and death within one year. Secondary endpoints included angiographic and clinical success, thrombolysis duration, additional interventions, conversion, and quality of life. RESULTS: The study included 20 patients (16 men; median age 68.0 years; range, 50.0 - 83.0; and 40% native artery and 60% bypass graft). In all patients, the use of microbubble contrast enhanced sonothrombolysis could be applied successfully. There were no serious adverse events related to the experimental treatment. Duplex examination showed flow distal from the occlusion after 23.1 hours (range 3.1 - 46.5) with a median thrombolysis time of 47.5 hours (range 6.0 - 81.0). The short term ABI and pain scores significantly improved; however, no changes were observed before or after thrombolysis in the microcirculation. Overall mortality and amputation rates were both 2% within one year. The one year patency rate was 55%. CONCLUSION: Treatment of patients with acute peripheral arterial occlusions with contrast enhanced sonothrombolysis is feasible and safe to perform in patients. Further research is necessary to investigate the superiority of this new treatment over standard treatment.


Assuntos
Fibrinolíticos/administração & dosagem , Isquemia/terapia , Microbolhas , Doença Arterial Periférica/terapia , Terapia Trombolítica , Terapia por Ultrassom , Idoso , Idoso de 80 Anos ou mais , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Isquemia/diagnóstico por imagem , Isquemia/fisiopatologia , Masculino , Microbolhas/efeitos adversos , Pessoa de Meia-Idade , Países Baixos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Terapia por Ultrassom/efeitos adversos , Grau de Desobstrução Vascular
6.
J Cachexia Sarcopenia Muscle ; 12(4): 1056-1063, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34102017

RESUMO

BACKGROUND: There is limited information about the impact of coronavirus disease (COVID-19) on the muscular dysfunction, despite the generalized weakness and fatigue that patients report after overcoming the acute phase of the infection. This study aimed to detect impaired muscle efficiency by evaluating delta efficiency (DE) in patients with COVID-19 compared with subjects with chronic obstructive pulmonary disease (COPD), ischaemic heart disease (IHD), and control group (CG). METHODS: A total of 60 participants were assigned to four experimental groups: COVID-19, COPD, IHD, and CG (n = 15 each group). Incremental exercise tests in a cycle ergometer were performed to obtain peak oxygen uptake (VO2 peak). DE was obtained from the end of the first workload to the power output where the respiratory exchange ratio was 1. RESULTS: A lower DE was detected in patients with COVID-19 and COPD compared with those in CG (P ≤ 0.033). However, no significant differences were observed among the experimental groups with diseases (P > 0.05). Lower VO2 peak, peak ventilation, peak power output, and total exercise time were observed in the groups with diseases than in the CG (P < 0.05). A higher VO2 , ventilation, and power output were detected in the CG compared with those in the groups with diseases at the first and second ventilatory threshold (P < 0.05). A higher power output was detected in the IHD group compared with those in the COVID-19 and COPD groups (P < 0.05) at the first and second ventilatory thresholds and when the respiratory exchange ratio was 1. A significant correlation (P < 0.001) was found between the VO2 peak and DE and between the peak power output and DE (P < 0.001). CONCLUSIONS: Patients with COVID-19 showed marked mechanical inefficiency similar to that observed in COPD and IHD patients. Patients with COVID-19 and COPD showed a significant decrease in power output compared to IHD during pedalling despite having similar response in VO2 at each intensity. Resistance training should be considered during the early phase of rehabilitation.


Assuntos
COVID-19/fisiopatologia , Teste de Esforço/métodos , Exercício Físico/fisiologia , Pulmão/fisiopatologia , Consumo de Oxigênio/fisiologia , COVID-19/virologia , Cardiopatias/fisiopatologia , Humanos , Isquemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Treinamento de Força/métodos , Testes de Função Respiratória/métodos , SARS-CoV-2/fisiologia
7.
Urol Int ; 105(9-10): 916-919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34107472

RESUMO

Infection by COVID-19, being a respiratory disease caused by SARS-CoV-2, can predispose to arterial and venous thrombotic disease, in response to excessive inflammation, platelet activation, endothelial dysfunction, and venous stasis. During the COVID-19 pandemic period, the technological and resource availability for the care of these patients with thrombotic disease is critical, marking a factor of morbidity and poor prognosis in these cases. We describe a case of priapism in a patient with COVID-19, during the course of systemic inflammatory response syndrome and respiratory distress syndrome with a procoagulant state, seeking to relate the pathophysiological factors of ischemic priapism in patients with infection with SARS-Cov-2.


Assuntos
COVID-19/complicações , Isquemia/etiologia , Ereção Peniana , Pênis/irrigação sanguínea , Priapismo/etiologia , Adulto , COVID-19/diagnóstico , COVID-19/virologia , Evolução Fatal , Humanos , Isquemia/diagnóstico , Isquemia/fisiopatologia , Masculino , Priapismo/diagnóstico , Priapismo/fisiopatologia , Fluxo Sanguíneo Regional
8.
Int J Mol Sci ; 22(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071589

RESUMO

The complement system is a potent inflammatory trigger, activator, and chemoattractant for leukocytes, which play a crucial role in promoting angiogenesis. However, little information is available about the influence of the complement system on angiogenesis in ischemic muscle tissue. To address this topic and analyze the impact of the complement system on angiogenesis, we induced muscle ischemia in complement factor C3 deficient (C3-/-) and wildtype control mice by femoral artery ligation (FAL). At 24 h and 7 days after FAL, we isolated the ischemic gastrocnemius muscles and investigated them by means of (immuno-)histological analyses. C3-/- mice showed elevated ischemic damage 7 days after FAL, as evidenced by H&E staining. In addition, angiogenesis was increased in C3-/- mice, as demonstrated by increased capillary/muscle fiber ratio and increased proliferating endothelial cells (CD31+/BrdU+). Moreover, our results showed that the total number of leukocytes (CD45+) was increased in C3-/- mice, which was based on an increased number of neutrophils (MPO+), neutrophil extracellular trap formation (MPO+/CitH3+), and macrophages (CD68+) displaying a shift toward an anti-inflammatory and pro-angiogenic M2-like polarized phenotype (CD68+/MRC1+). In summary, we show that the deficiency of complement factor C3 increased neutrophil and M2-like polarized macrophage accumulation in ischemic muscle tissue, contributing to angiogenesis.


Assuntos
Capilares/fisiopatologia , Complemento C3/deficiência , Isquemia/fisiopatologia , Leucócitos/metabolismo , Músculo Esquelético/fisiopatologia , Animais , Capilares/metabolismo , Complemento C3/genética , Modelos Animais de Doenças , Imunofluorescência/métodos , Humanos , Isquemia/genética , Ativação de Macrófagos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Infiltração de Neutrófilos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo
9.
PLoS Comput Biol ; 17(6): e1009019, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34143772

RESUMO

The anatomical and functional organization of neurons and astrocytes at 'tripartite synapses' is essential for reliable neurotransmission, which critically depends on ATP. In low energy conditions, synaptic transmission fails, accompanied by a breakdown of ion gradients, changes in membrane potentials and cell swelling. The resulting cellular damage and cell death are causal to the often devastating consequences of an ischemic stroke. The severity of ischemic damage depends on the age and the brain region in which a stroke occurs, but the reasons for this differential vulnerability are far from understood. In the present study, we address this question by developing a comprehensive biophysical model of a glutamatergic synapse to identify key determinants of synaptic failure during energy deprivation. Our model is based on fundamental biophysical principles, includes dynamics of the most relevant ions, i.e., Na+, K+, Ca2+, Cl- and glutamate, and is calibrated with experimental data. It confirms the critical role of the Na+/K+-ATPase in maintaining ion gradients, membrane potentials and cell volumes. Our simulations demonstrate that the system exhibits two stable states, one physiological and one pathological. During energy deprivation, the physiological state may disappear, forcing a transit to the pathological state, which can be reverted when blocking voltage-gated Na+ and K+ channels. Our model predicts that the transition to the pathological state is favoured if the extracellular space fraction is small. A reduction in the extracellular space volume fraction, as, e.g. observed with ageing, will thus promote the brain's susceptibility to ischemic damage. Our work provides new insights into the brain's ability to recover from energy deprivation, with translational relevance for diagnosis and treatment of ischemic strokes.


Assuntos
Íons/metabolismo , Sinapses/metabolismo , Potenciais de Ação/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Encéfalo/fisiologia , Metabolismo Energético , Proteínas de Transporte de Glutamato da Membrana Plasmática/antagonistas & inibidores , Homeostase , Isquemia/fisiopatologia , Camundongos , Modelos Neurológicos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Transmissão Sináptica
10.
Biochim Biophys Acta Proteins Proteom ; 1869(9): 140683, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34119693

RESUMO

Myocardial infarction and subsequent therapeutic interventions activate numerous intracellular cascades in every constituent cell type of the heart. Endothelial cells produce several protective compounds in response to therapeutic ultrasound, under both normoxic and ischemic conditions. How endothelial cells sense ultrasound and convert it to a beneficial biological response is not known. We adopted a global, unbiased phosphoproteomics approach aimed at understanding how endothelial cells respond to ultrasound. Here, we use primary cardiac endothelial cells to explore the cellular signaling events underlying the response to ischemia-like cellular injury and ultrasound exposure in vitro. Enriched phosphopeptides were analyzed with a high mass accuracy liquid chromatrography (LC) - tandem mass spectrometry (MS/MS) proteomic platform, yielding multiple alterations in both total protein levels and phosphorylation events in response to ischemic injury and ultrasound. Application of pathway algorithms reveals numerous protein networks recruited in response to ultrasound including those regulating RNA splicing, cell-cell interactions and cytoskeletal organization. Our dataset also permits the informatic prediction of potential kinases responsible for the modifications detected. Taken together, our findings begin to reveal the endothelial proteomic response to ultrasound and suggest potential targets for future studies of the protective effects of ultrasound in the ischemic heart.


Assuntos
Endocárdio/metabolismo , Isquemia Miocárdica/fisiopatologia , Fosfoproteínas/metabolismo , Sequência de Aminoácidos , Animais , Cromatografia Líquida/métodos , Endocárdio/fisiologia , Células Endoteliais/metabolismo , Coração/diagnóstico por imagem , Isquemia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Cultura Primária de Células , Proteoma/metabolismo , Proteômica/métodos , Transdução de Sinais , Espectrometria de Massas em Tandem/métodos , Terapia por Ultrassom/métodos
11.
Invest Ophthalmol Vis Sci ; 62(7): 10, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34100891

RESUMO

Purpose: To evaluate anatomic-functional associations at sites of retinal lesions in retinal vein occlusion (RVO). Methods: This pilot, prospective, observational study was conducted at the Northern Ireland Clinical Research Facility (NICRF) of Queen's University and the Belfast Health and Social Care Trust, Northern Ireland, between August 1, 2018, and September 30, 2019. The study included 10 treatment-naïve patients with RVO (10 RVO eyes and 10 fellow eyes). There were 81 points/sites assessed for each eye at baseline; six patients were re-assessed 6 months after anti-vascular endothelial growth factor therapy at the same locations. We investigated associations between retinal sensitivity and presence of structural RVO lesions, including retinal ischemia, hemorrhages, intraretinal fluid (IRF) and subretinal fluid outside the foveal/parafoveal regions. Comparisons were made between RVO eyes and fellow eyes at baseline, and between RVO eyes at baseline and at 6 months after treatment. Regression models were used to investigate anatomic-functional associations. Results: At baseline, strong associations were found between reduced retinal sensitivity and presence of ischemia (estimate = -2.08 dB; P < 0.001), intraretinal fluid (estimate = -7.82 dB; P < 0.001), and subretinal fluid (estimate = -8.66 dB; P < 0.001). Resolution of subretinal fluid but not intraretinal fluid was associated with improved function (estimate = 2.40 dB [P = 0.022]; estimate = 1.16 dB [P = 0.228], respectively). However, reperfusion of ischemic retina, observed in 31 of 486 points (6%) 6 months after anti-vascular endothelial growth factor therapy, was associated with a further decrease in retinal sensitivity (estimate = -2.34 dB; P = 0.035). Conclusions: Retinal sensitivity was decreased at sites of RVO lesions. Decreased function at sites of retinal ischemia did not recover after treatment, even when reperfusion occurred.


Assuntos
Fatores de Crescimento Endotelial/farmacologia , Fóvea Central/irrigação sanguínea , Isquemia , Retina , Oclusão da Veia Retiniana , Inibidores da Angiogênese/farmacologia , Sensibilidades de Contraste/efeitos dos fármacos , Feminino , Angiofluoresceinografia/métodos , Fundo de Olho , Humanos , Injeções Intravítreas , Isquemia/diagnóstico , Isquemia/fisiopatologia , Isquemia/terapia , Masculino , Pessoa de Meia-Idade , Retina/diagnóstico por imagem , Retina/patologia , Retina/fisiopatologia , Veia Retiniana , Oclusão da Veia Retiniana/diagnóstico , Oclusão da Veia Retiniana/fisiopatologia , Oclusão da Veia Retiniana/terapia , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento , Acuidade Visual
12.
Am J Physiol Regul Integr Comp Physiol ; 321(2): R112-R124, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34075808

RESUMO

Preeclampsia (PE) is characterized by maternal hypertension, intrauterine growth restriction, and increased cytolytic natural killer cells (cNKs), which secrete interferon γ (IFNγ). However, the precise role of IFNγ in contributing to PE pathophysiology remains unclear. Using the reduced uterine perfusion pressure (RUPP) rat model of placental ischemia, we tested the hypothesis that neutralization of IFNγ in RUPPs will decrease placental reactive oxygen species (ROS) and improve vascular function resulting in decreased MAP and improved fetal growth. On gestation day (GD) 14, the RUPP procedure was performed and on GDs 15 and 18, a subset of normal pregnant rats (NP) and RUPP rats were injected with 10 µg/kg of an anti-rat IFNγ monoclonal antibody. On GD 18, uterine artery resistance index (UARI) was measured via Doppler ultrasound and on GD 19, mean arterial pressure (MAP) was measured, animals were euthanized, and blood and tissues were collected for analysis. Increased MAP was observed in RUPP rats compared with NP and was reduced in RUPP + anti-IFNγ. Placental ROS was also increased in RUPP rats compared with NP rats and was normalized in RUPP + anti-IFNγ. Fetal and placental weights were reduced in RUPP rats, but were not improved following anti-IFNγ treatment. However, UARI was elevated in RUPP compared with NP rats and was reduced in RUPP + anti-IFNγ. In conclusion, we observed that IFNγ neutralization reduced MAP, UARI, and placental ROS in RUPP recipients. These data suggest that IFNγ is a potential mechanism by which cNKs contribute to PE pathophysiology and may represent a therapeutic target to improve maternal outcomes in PE.


Assuntos
Anticorpos Monoclonais/farmacologia , Pressão Arterial/efeitos dos fármacos , Interferon gama/antagonistas & inibidores , Células Matadoras Naturais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Placenta/irrigação sanguínea , Placenta/efeitos dos fármacos , Pré-Eclâmpsia/prevenção & controle , Artéria Uterina/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos , Proteínas Angiogênicas/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/fisiopatologia , Retardo do Crescimento Fetal/prevenção & controle , Interferon gama/metabolismo , Isquemia/metabolismo , Isquemia/fisiopatologia , Células Matadoras Naturais/metabolismo , Placenta/metabolismo , Circulação Placentária , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/fisiopatologia , Gravidez , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Artéria Uterina/metabolismo , Artéria Uterina/fisiopatologia
13.
J Am Soc Nephrol ; 32(8): 1987-2004, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34135081

RESUMO

BACKGROUND: Peripheral vascular diseases may induce chronic ischemia and cellular injury distal to the arterial obstruction. Cellular senescence involves proliferation arrest in response to stress, which can damage neighboring cells. Renal artery stenosis (RAS) induces stenotic-kidney dysfunction and injury, but whether these arise from cellular senescenceand their temporal pattern remain unknown. METHODS: Chronic renal ischemia was induced in transgenic INK-ATTAC and wild type C57BL/6 mice by unilateral RAS, and kidney function (in vivo micro-MRI) and tissue damage were assessed. Mouse healthy and stenotic kidneys were analyzed using unbiased single-cell RNA-sequencing. To demonstrate translational relevance, cellular senescence was studied in human stenotic kidneys. RESULTS: Using intraperitoneal AP20187 injections starting 1, 2, or 4 weeks after RAS, selective clearance of cells highly expressing p16Ink4a attenuated cellular senescence and improved stenotic-kidney function; however, starting treatment immediately after RAS induction was unsuccessful. Broader clearance of senescent cells, using the oral senolytic combination dasatinib and quercetin, in C57BL/6 RAS mice was more effective in clearing cells positive for p21 (Cdkn1a) and alleviating renal dysfunction and damage. Unbiased, single-cell RNA sequencing in freshly dissociated cells from healthy and stenotic mouse kidneys identified stenotic-kidney epithelial cells undergoing both mesenchymal transition and senescence. As in mice, injured human stenotic kidneys exhibited cellular senescence, suggesting this process is conserved. CONCLUSIONS: Maladaptive tubular cell senescence, involving upregulated p16 (Cdkn2a), p19 (Cdkn2d), and p21 (Cdkn1a) expression, is associated with renal dysfunction and injury in chronic ischemia. These findings support development of senolytic strategies to delay chronic ischemic renal injury.


Assuntos
Senescência Celular/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Isquemia/fisiopatologia , Rim/fisiopatologia , Insuficiência Renal Crônica/fisiopatologia , Quinases Ativadas por p21/metabolismo , Animais , Apoptose/efeitos dos fármacos , Caspase 8/metabolismo , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Doença Crônica , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p19/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Dasatinibe/farmacologia , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Células Epiteliais/fisiologia , Transição Epitelial-Mesenquimal , Expressão Gênica , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/genética , Humanos , Isquemia/etiologia , Rim/irrigação sanguínea , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Osteopontina/genética , Inibidores de Proteínas Quinases/farmacologia , Obstrução da Artéria Renal/complicações , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/patologia , Análise de Sequência de RNA , Análise de Célula Única , Tacrolimo/análogos & derivados , Tacrolimo/farmacologia , Regulação para Cima , Quinases Ativadas por p21/genética
14.
Am J Physiol Regul Integr Comp Physiol ; 320(6): R972-R983, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33949210

RESUMO

Peripheral artery disease (PAD) in the lower limb compromises oxygen supply due to arterial occlusion. Ischemic skeletal muscle is accompanied by capillary structural deformation. Therefore, using novel microscopy techniques, we tested the hypothesis that endothelial cell swelling temporally and quantitatively corresponds to enhanced microvascular permeability. Hindlimb ischemia was created in male Wistar rat's by iliac artery ligation (AL). The tibialis anterior (TA) muscle microcirculation was imaged using intravenously infused rhodamine B isothiocyanate dextran fluorescent dye via two-photon laser scanning microscopy (TPLSM) and dye extravasation at 3 and 7 days post-AL quantified to assess microvascular permeability. The TA microvascular endothelial ultrastructure was analyzed by transmission electron microscopy (TEM). Compared with control (0.40 ± 0.15 µm3 × 106), using TPLSM, the volumetrically determined interstitial leakage of fluorescent dye measured at 3 (3.0 ± 0.40 µm3 × 106) and 7 (2.5 ± 0.8 µm3 × 106) days was increased (both P < 0.05). Capillary wall thickness was also elevated at 3 (0.21 ± 0.06 µm) and 7 (0.21 ± 0.08 µm) days versus control (0.11 ± 0.03 µm, both P < 0.05). Capillary endothelial cell swelling was temporally and quantitatively associated with elevated vascular permeability in the AL model of PAD but these changes occurred in the absence of elevations in protein levels of vascular endothelial growth factor (VEGF) its receptor (VEGFR2 which decreased by AL-7 day) or matrix metalloproteinase. The temporal coherence of endothelial cell swelling and increased vascular permeability supports a common upstream mediator. TPLSM, in combination with TEM, provides a sensitive and spatially discrete technique to assess the mechanistic bases for, and efficacy of, therapeutic countermeasures to the pernicious sequelae of compromised peripheral arterial function.


Assuntos
Permeabilidade Capilar/fisiologia , Isquemia/fisiopatologia , Microscopia Confocal , Músculo Esquelético/irrigação sanguínea , Animais , Membro Posterior/fisiopatologia , Ligadura/métodos , Microcirculação/fisiologia , Microscopia Confocal/métodos , Microvasos/fisiopatologia , Neovascularização Fisiológica/fisiologia , Ratos Wistar
15.
J Vis Exp ; (170)2021 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-33970127

RESUMO

In approximately half of the patients undergoing coronary angiography for angina pectoris or for signs or symptoms suggestive of ischemic heart disease, no obstructive coronary artery disease is angiographically visible. The majority of these patients with angina or ischemia and no obstructive coronary artery disease (INOCA) have an underlying coronary vasomotor dysfunction, and current consensus documents recommend diagnostic invasive coronary vasomotor function testing (CFT). During CFT, a variety of vasomotor dysfunction endotypes can be assessed, including vasospastic coronary dysfunction (epicardial or microvascular vasospasm), and/or microvascular vasodilatory dysfunction, including impaired vasodilatory capacity and increased microvascular resistance. The quantification of the continuous thermodilution derived absolute coronary blood flow and resistance might be a better measure compared to the currently used standard physiologic measures. This article provides an overview of this continuous thermodilution method.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Circulação Coronária/fisiologia , Isquemia/fisiopatologia , Termodiluição/métodos , Humanos
16.
J Vis Exp ; (170)2021 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-33938886

RESUMO

Blood flow recovery is a critical outcome measure after experimental hindlimb ischemia or ischemia-reperfusion. Laser Doppler perfusion imaging (LDPI) is a common, noninvasive, repeatable method for assessing blood flow recovery. The technique calculates overall blood flow in the sampled tissue from the Doppler shift in frequency caused when a laser hits moving red blood cells. Measurements are expressed in arbitrary perfusion units, so the contralateral non-intervened upon leg is usually used to help control measurements. Measurement depth is in the range of 0.3-1 mm; for hindlimb ischemia, this means that dermal perfusion is assessed. Dermal perfusion is dependent on several factors-most importantly skin temperature and anesthetic agent, which must be carefully controlled to result in reliable readings. Furthermore, hair and skin pigmentation can alter the ability of the laser to either reach or penetrate to the dermis. This article demonstrates the technique of LDPI in the mouse hindlimb.


Assuntos
Membro Posterior/diagnóstico por imagem , Animais , Hemodinâmica , Membro Posterior/irrigação sanguínea , Isquemia/diagnóstico por imagem , Isquemia/fisiopatologia , Fluxometria por Laser-Doppler , Lasers , Camundongos , Perfusão/métodos , Fluxo Sanguíneo Regional , Reperfusão
20.
Optom Vis Sci ; 98(4): 418-424, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33828041

RESUMO

SIGNIFICANCE: Although von Willebrand disease is the most common inherited bleeding disorder, there are only a few published reports of ocular complications. To our knowledge, this is the first case of peripheral retinal ischemia and retinal neovascularization in a patient with von Willebrand disease. PURPOSE: This study aimed to demonstrate the value of multispecialty care when exploring a diagnosis for bilateral retinopathy. CASE REPORT: A 55-year-old African American woman presented with peripheral retinal hemorrhages on routine examination. She was asymptomatic and did not have any personal or family history of bleeding disorders. Blood work was ordered, and she was referred to a retinal specialist who found peripheral telangiectasia, retinal ischemia, and leakage on fluorescein angiography, consistent with retinal neovascularization. Laser photocoagulation was performed while numerous specialists were consulted to determine the cause for her retinopathy. Laboratory testing confirmed low-grade type 1 von Willebrand disease. She was monitored without systemic treatment. She remained stable and asymptomatic, but her retinal neovascularization did not regress fully, so laser treatment was repeated. CONCLUSIONS: This case described a new finding of peripheral retinal ischemia and retinal neovascularization in von Willebrand disease. It was discovered in an asymptomatic patient who did not have a history of bleeding but presented with bilateral retinal hemorrhages. Diagnosis was challenging because of the high degree of variation in this bleeding disorder, requiring extensive testing and careful consideration of the individual's clinical profile. Most people with von Willebrand disease do not know they have the disease because symptoms are mild or absent, so most cases are unreported. The von Willebrand factor is poorly recognized in ocular disease, but given its role in angiogenesis, it may be a valuable target to consider in future research.


Assuntos
Isquemia/etiologia , Neovascularização Retiniana/etiologia , Vasos Retinianos/patologia , Doenças de von Willebrand/complicações , Feminino , Angiofluoresceinografia , Humanos , Isquemia/complicações , Isquemia/diagnóstico , Isquemia/fisiopatologia , Pessoa de Meia-Idade , Neovascularização Retiniana/complicações , Neovascularização Retiniana/diagnóstico , Neovascularização Retiniana/fisiopatologia , Acuidade Visual/fisiologia , Doenças de von Willebrand/diagnóstico , Doenças de von Willebrand/tratamento farmacológico , Fator de von Willebrand/uso terapêutico
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