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1.
Proc Biol Sci ; 291(2017): 20232541, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38378149

RESUMO

Inter-individual transmission of cancer cells represents a unique form of microparasites increasingly reported in marine bivalves. In this study, we sought to understand the ecology of the propagation of Mytilus trossulus Bivalve Transmissible Neoplasia 2 (MtrBTN2), a transmissible cancer affecting four Mytilus mussel species worldwide. We investigated the prevalence of MtrBTN2 in the mosaic hybrid zone of M. edulis and M. galloprovincialis along the French Atlantic coast, sampling contrasting natural and anthropogenic habitats. We observed a similar prevalence in both species, probably due to the spatial proximity of the two species in this region. Our results showed that ports had higher prevalence of MtrBTN2, with a possible hotspot observed at a shuttle landing dock. No cancer was found in natural beds except for two sites close to the hotspot, suggesting spillover. Ports may provide favourable conditions for the transmission of MtrBTN2, such as high mussel density, stressful conditions, sheltered and confined shores or buffered temperatures. Ships may also spread the disease through biofouling. Our results suggest ports may serve as epidemiological hubs, with maritime routes providing artificial gateways for MtrBTN2 propagation. This highlights the importance of preventing biofouling on docks and ship hulls to limit the spread of marine pathogens hosted by fouling species.


Assuntos
Mytilus , Neoplasias , Animais , Neoplasias/epidemiologia
2.
Cureus ; 15(7): e42533, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37637533

RESUMO

Abiraterone, an androgen biosynthesis inhibitor drug approved by the Food and Drug Administration (FDA) in 2011 for the treatment of metastatic prostate cancer, has seen an increase in prescriptions over the years, owing largely to the aging population and the association of prostate cancer with increasing age. As the rate of abiraterone prescription increases, it is important for physicians to be aware of its adverse effects profile to improve patient outcomes. This case report explains the mechanism, clinical presentation, and management of abiraterone-induced hypokalemia in a 67-year-old male with prostate cancer and highlights the importance of close monitoring and management of electrolyte levels for patients on abiraterone.

3.
Hypertension ; 80(5): 901-911, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36748474

RESUMO

Drugs acting by inhibition of the angiogenic action of VEGF (vascular endothelial growth factor) have become major instruments in the treatment of cancer. The downside of their favorable effects in cancer treatment is their frequent cardiovascular side effects. The most consistent finding thus far on the cardiovascular side effects of VEGF inhibitors is the high incidence of hypertension. In this short review, we discuss the evidence that hypertension occurring during VEGF inhibitor treatment is caused by microvascular rarefaction. After a review of the role of VEGF in microvascular growth and differentiation, we present evidence from studies in experimental models of hypertension as well as clinical studies on the microvascular network changes during and after VEGF inhibitor treatment.


Assuntos
Hipertensão , Rarefação Microvascular , Neoplasias , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Rarefação Microvascular/induzido quimicamente , Rarefação Microvascular/complicações , Rarefação Microvascular/tratamento farmacológico , Fatores de Crescimento do Endotélio Vascular , Neoplasias/tratamento farmacológico , Inibidores da Angiogênese/efeitos adversos
4.
J Invertebr Pathol ; 168: 107271, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31629707

RESUMO

Marine mussel production is of substantial economic interest in numerous coastal areas worldwide, making crucial the study of pathologies that affect them. Disseminated neoplasia (DN) has recently been suggested to be linked to blue mussel, Mytilus edulis, mortality outbreaks observed in France since 2014, although the evidence remains indirect. In order to improve DN detection and monitoring, we compared the sensitivity of four diagnostic tools, namely haemocytology, histology, flow cytometry, and genetics. Haemocytological examination gave the best results in sensitivity and had the advantage of being non-invasive, allowing disease progression to be followed in affected mussels. Using this approach, we showed that DN progression is usually slow, and we provide evidence of remission events. We observed a high diversity of forms and mitotic features of neoplastic cells located in the vesicular connective tissue but rarely in the haemolymph. Circulating cells occur as four main types but are homogenous in morphology and DNA content within a single individual. Polyploidy proved very high, from 8 N to 18 N. Genetic analysis of haemolymph DNA showed that a Mytilus trossulus genetic signal was associated with almost all the DN cases here diagnosed by haemocytological examination, regardless of the DN type. This result corroborates DN is a transmissible cancer that first originated in a M. trossulus host and subsequently crossed into M. edulis. No pre-neoplastic conditions were detectable. The prevalence of the disease was quite low, which, together with the low morbidity observed in the lab, suggest DN is unlikely to be the direct cause of mortality outbreaks in France.


Assuntos
Mytilus edulis , Neoplasias de Tecido Conjuntivo/veterinária , Neoplasias/veterinária , Animais , Aquicultura , Progressão da Doença , Citometria de Fluxo/métodos , França/epidemiologia , Técnicas de Genotipagem , Hemolinfa/citologia , Incidência , Mortalidade , Mytilus , Mytilus edulis/citologia , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/patologia , Neoplasias de Tecido Conjuntivo/epidemiologia , Neoplasias de Tecido Conjuntivo/genética , Neoplasias de Tecido Conjuntivo/patologia , Ploidias , Prevalência
5.
J Hypertens ; 37(1): 175-181, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30036269

RESUMO

CONTEXT: Controversial data exist on cardiovascular damages in patients with congenital adrenal hyperplasia (CAH). OBJECTIVE: To assess blood pressure and early cardiovascular damages on a large cohort of adult CAH patients and control individuals. DESIGN: Case-control study. SETTING: Referral Center for Rare Disease, Pitié Salpêtrière Hospital, Paris, France. PATIENTS OR OTHER PARTICIPANTS: Fifty-eight women and 26 men with CAH diagnosed in childhood and 85 controls matched-paired for sex, age and smoking status were prospectively included. INTERVENTION: Measurement of large arteries and microcirculatory anatomical and functional indices as well as hormonal status and cardiovascular risk factors evaluation. MAIN OUTCOME MEASURE: The primary objective was to compare carotid intima-media thickness (cIMT) in CAH patients and controls. The secondary objectives were to compare blood pressure (BP), radial augmentation index (rAI), central BP, carotid-femoral pulse wave velocity (PWV), skin microcirculation indices and inflammation parameters in CAH patients and controls. RESULTS: Although PWV and cIMT were identical in patients and controls, higher rAI (64.6 ±â€Š1.7 vs. 59.9 ±â€Š1.6%, P = 0.02) and higher central SBP (101.8 ±â€Š1.5 vs. 95.1 ±â€Š1.5 mmHg, P < 0.001) were observed in CAH patients. Regarding microcirculatory indices, there was a higher functional resting capacity and a lower anatomical capillary density in CAH patients. In multivariate analysis, we found an independant association between CAH and central SBP elevation. CONCLUSION: We found an early rise in central SBP in CAH patients whereas sublinical arterial damages markers were normal. Our study suggest that vascular damages and increased cardiovascular risk could be mainly BP-driven.


Assuntos
Hiperplasia Suprarrenal Congênita , Pressão Sanguínea/fisiologia , Hiperplasia Suprarrenal Congênita/epidemiologia , Hiperplasia Suprarrenal Congênita/fisiopatologia , Adulto , Espessura Intima-Media Carotídea , Criança , Feminino , Humanos , Estudos Prospectivos , Análise de Onda de Pulso
6.
Stem Cells Int ; 2018: 2431567, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29736174

RESUMO

Clinical trials of cell therapy in stroke favor autologous cell transplantation. To date, feasibility studies have used bone marrow-derived mononuclear cells, but harvesting bone marrow cells is invasive thus complicating bedside treatment. We investigated the therapeutic potential of peripheral blood-derived mononuclear cells (PB-MNC) harvested from diabetic patients and stimulated by ephrin-B2 (PB-MNC+) (500,000 cells), injected intravenously 18-24 hours after induced cerebral ischemia in mice. Infarct volume, neurological deficit, neurogenesis, angiogenesis, and inflammation were investigated as were the potential mechanisms of PB-MNC+ cells in poststroke neurorepair. At D3, infarct volume was reduced by 60% and 49% compared to unstimulated PB-MNC and PBS-treated mice, respectively. Compared to PBS, injection of PB-MNC+ increased cell proliferation in the peri-infarct area and the subventricular zone, decreased microglia/macrophage cell density, and upregulated TGF-ß expression. At D14, microvessel density was decreased and functional recovery was enhanced compared to PBS-treated mice, whereas plasma levels of BDNF, a major regulator of neuroplasticity, were increased in mice treated with PB-MNC+ compared to the other two groups. Cell transcriptional analysis showed that ephrin-B2 induced phenotype switching of PB-MNC by upregulating genes controlling cell proliferation, inflammation, and angiogenesis, as confirmed by adhesion and Matrigel assays. Conclusions. This feasibility study suggests that PB-MNC+ transplantation poststroke could be a promising approach but warrants further investigation. If confirmed, this rapid, noninvasive bedside cell therapy strategy could be applied to stroke patients at the acute phase.

7.
Angiogenesis ; 21(3): 557-569, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29516292

RESUMO

The pathophysiology of sporadic Alzheimer's disease (AD) remains uncertain. Along with brain amyloid-ß (Aß) deposits and neurofibrillary tangles, cerebrovascular dysfunction is increasingly recognized as fundamental to the pathogenesis of AD. Using an experimental model of limb ischemia in transgenic APPPS1 mice, a model of AD (AD mice), we showed that microvascular impairment also extends to the peripheral vasculature in AD. At D70 following femoral ligation, we evidenced a significant decrease in cutaneous blood flow (- 29%, P < 0.001), collateral recruitment (- 24%, P < 0.001), capillary density (- 22%; P < 0.01) and arteriole density (- 28%; P < 0.05) in hind limbs of AD mice compared to control WT littermates. The reactivity of large arteries was not affected in AD mice, as confirmed by unaltered size, and vasoactive responses to pharmacological stimuli of the femoral artery. We identified blood as the only source of Aß in the hind limb; thus, circulating Aß is likely responsible for the impairment of peripheral vasculature repair mechanisms. The levels of the majority of pro-angiogenic mediators were not significantly modified in AD mice compared to WT mice, except for TGF-ß1 and PlGF-2, both of which are involved in vessel stabilization and decreased in AD mice (P = 0.025 and 0.019, respectively). Importantly, endothelin-1 levels were significantly increased, while those of nitric oxide were decreased in the hind limb of AD mice (P < 0.05). Our results suggest that vascular dysfunction is a systemic disorder in AD mice. Assessment of peripheral vascular function may therefore provide additional tools for early diagnosis and management of AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Membro Posterior/fisiopatologia , Isquemia/fisiopatologia , Doenças Vasculares Periféricas/fisiopatologia , Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Arteríolas/metabolismo , Arteríolas/fisiopatologia , Capilares/metabolismo , Capilares/fisiopatologia , Modelos Animais de Doenças , Endotelina-1/sangue , Artéria Femoral/metabolismo , Artéria Femoral/fisiopatologia , Membro Posterior/irrigação sanguínea , Humanos , Isquemia/genética , Camundongos , Camundongos Transgênicos , Microcirculação/genética , Óxido Nítrico/sangue , Doenças Vasculares Periféricas/sangue , Doenças Vasculares Periféricas/genética , Fator de Crescimento Placentário/sangue , Fator de Crescimento Transformador beta1/sangue
8.
J Vasc Access ; 17(3): 205-9, 2016 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-27056025

RESUMO

PURPOSE: To choose the best arterial tourniquet for angioaccess surgery. METHODS: Preventive hemostasis with an arterial tourniquet prevents bleeding and provides better visualization. The surgeon may currently use a traditional wide nonsterile inflatable pneumatic cuff after exsanguination with an Esmarch bandage or a disposable sterile narrow elastic silicone ring (HemaClear®), available in different sizes according to the patient's limb circumference and blood pressure. RESULTS: The latter is easily rolled up the upper limb after surgical draping, to achieve exsanguination and occlusion of the proximal brachial artery, thus providing a wide sterile field that is most useful for upper arm vein superficialization or arteriovenous fistula (AVF) revision. Although rare, neurological complications must be prevented by limiting the compressive force applied to the tissues to occlude the arteries and the veins. Such tissues are almost non-compressible but deformable; thus, they may be elongated and damaged, mostly at both extremities of the tourniquet, especially the nerves. The compressive force (kg) applied to the limb by the cuff is the product of the cuff pressure (mm Hg) imposed and the surface (cm²) of the skin in contact with the cuff. Reduction of the cuff surface results in reduction of the volume of tissue beneath the cuff and therefore in limitation of the compressive force. CONCLUSIONS: From a theoretical point of view and from clinical data, it seems therefore reasonable to recommend the use of a narrower cuff size and, for practical reasons, the silicon ring.


Assuntos
Derivação Arteriovenosa Cirúrgica , Perda Sanguínea Cirúrgica/prevenção & controle , Equipamentos Descartáveis , Hemostasia Cirúrgica/instrumentação , Diálise Renal , Torniquetes , Extremidade Superior/irrigação sanguínea , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Elasticidade , Desenho de Equipamento , Hemostasia Cirúrgica/efeitos adversos , Humanos , Complicações Pós-Operatórias/etiologia , Pressão , Reoperação , Silício , Resultado do Tratamento
9.
J Neurosci Res ; 93(9): 1451-61, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25944265

RESUMO

Neuropathy is the most common complication of the peripheral nervous system during the progression of diabetes. The pathophysiology is unclear but may involve microangiopathy, reduced endoneurial blood flow, and tissue ischemia. We used a mouse model of type 1 diabetes to study parallel alterations of nerves and microvessels following tissue ischemia. We designed an easily reproducible model of ischemic neuropathy induced by irreversible ligation of the femoral artery. We studied the evolution of behavioral function, epineurial and endoneurial vessel impairment, and large nerve myelinated fiber as well as small cutaneous unmyelinated fiber impairment for 1 month following the onset of ischemia. We observed a more severe hindlimb dysfunction and delayed recovery in diabetic animals. This was associated with reduced density of large arteries in the hindlimb and reduced sciatic nerve epineurial blood flow. A reduction in sciatic nerve endoneurial capillary density was also observed, associated with a reduction in small unmyelinated epidermal fiber number and large myelinated sciatic nerve fiber dysfunction. Moreover, vascular recovery was delayed, and nerve dysfunction was still present in diabetic animals at day 28. This easily reproducible model provides clear insight into the evolution over time of the impact of ischemia on nerve and microvessel homeostasis in the setting of diabetes. © 2015 Wiley Periodicals, Inc.


Assuntos
Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Artéria Femoral/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Nervo Isquiático/fisiopatologia , Doenças Vasculares/fisiopatologia , Análise de Variância , Angiografia , Animais , Antibióticos Antineoplásicos/toxicidade , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Membro Posterior/fisiopatologia , Fluxometria por Laser-Doppler , Ligadura/efeitos adversos , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Condução Nervosa/fisiologia , Lectinas de Plantas/metabolismo , Nervo Isquiático/irrigação sanguínea , Nervo Isquiático/patologia , Estreptozocina/toxicidade , Fatores de Tempo , Doenças Vasculares/etiologia
10.
Cell Transplant ; 24(7): 1343-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24069908

RESUMO

Endothelial progenitor cell (EPC) transplantation has beneficial effects for therapeutic neovascularization. We therefore assessed the effect of a therapeutic strategy based on EPC administration in the healing of radiation-induced damage. To improve cell therapy for clinical use, we used pretreatment with ephrin B2-Fc (Eph-B2-Fc) and/or coadministration with smooth muscle progenitor cells. At day 3, EPCs promoted dermal wound healing in both nonirradiated and irradiated mice by 1.2- and 1.15-fold, respectively, compared with animals injected with phosphate-buffered saline. In addition, EPCs also improved skin-blood perfusion and capillary density in both irradiated and nonirradiated mice compared with PBS-injected animals. We also demonstrated that activation with Eph-B2-Fc increased wound closure by 1.6-fold compared with unstimulated EPCs in nonirradiated mice. Interestingly, the beneficial effect of Eph-B2-Fc was abolished in irradiated animals. In addition, we found that Eph-B2-Fc stimulation did not improve EPC-induced vascular permeability or adhesiveness compared to unstimulated EPCs. We hypothesized that this effect was due to high oxidative stress during irradiation, leading to inhibition of EPCs' beneficial effect on vascular function. In this line, we demonstrated that, in irradiated conditions, N-acetyl-l-cysteine treatment restored the beneficial effect of EPC stimulation with Eph-B2-Fc in the wound healing process. In conclusion, stimulation by Eph-B2-Fc improved the beneficial effect of EPCs in physiological conditions and irradiated conditions only in association with antioxidant treatment. Additionally, cotherapy was beneficial in pathological conditions.


Assuntos
Células Progenitoras Endoteliais/metabolismo , Miócitos de Músculo Liso/metabolismo , Cicatrização/efeitos dos fármacos , Idoso , Animais , Efrina-B2 , Feminino , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Pessoa de Meia-Idade
11.
Hypertension ; 65(1): 218-24, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25331846

RESUMO

Cerebrovascular impairment is frequent in patients with Alzheimer disease and is believed to influence clinical manifestation and severity of the disease. Cardiovascular risk factors, especially hypertension, have been associated with higher risk of developing Alzheimer disease. To investigate the mechanisms underlying the hypertension, Alzheimer disease cross talk, we established a mouse model of dual pathology by infusing hypertensive doses of angiotensin II into transgenic APPPS1 mice overexpressing mutated human amyloid precursor and presenilin 1 proteins. At 4.5 months, at the early stage of disease progression, only hypertensive APPPS1 mice presented impairment of temporal order memory performance in the episodic-like memory task. This cognitive deficit was associated with an increased number of cortical amyloid deposits (223±5 versus 207±5 plaques/mm(2); P<0.05) and a 2-fold increase in soluble amyloid levels in the brain and in plasma. Hypertensive APPPS1 mice presented several cerebrovascular alterations, including a 25% reduction in cerebral microvessel density and a 30% to 40% increase in cerebral vascular amyloid deposits, as well as a decrease in vascular endothelial growth factor A expression in the brain, compared with normotensive APPPS1 mice. Moreover, the brain levels of nitric oxide synthase 1 and 3 and the nitrite/nitrate levels were reduced in hypertensive APPPS1 mice (by 49%, 34%, and 33%, respectively, compared with wild-type mice; P<0.05). Our results indicate that hypertension accelerates the development of Alzheimer disease-related structural and functional alterations, partially through cerebral vasculature impairment and reduced nitric oxide production.


Assuntos
Doença de Alzheimer/complicações , Regulação da Expressão Gênica , Hipertensão/complicações , RNA/genética , Fator A de Crescimento do Endotélio Vascular/genética , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Modelos Animais de Doenças , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Hipertensão/genética , Hipertensão/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Reação em Cadeia da Polimerase , Fator A de Crescimento do Endotélio Vascular/biossíntese
12.
Acta Ophthalmol ; 92(5): e382-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25043792

RESUMO

PURPOSE: Determine the effect of repeated intravitreal injections of ranibizumab (0.5 mg; 0.05 ml) on retrobulbar blood flow velocities (BFVs) using ultrasound imaging quantification in twenty patients with exudative age-related macular degeneration treated for 6 months. METHODS: Visual acuity (ETDRS), central macular thickness (OCT), peak-systolic, end-diastolic and mean-BFVs in central retinal (CRA), temporal posterior ciliary (TPCA) and ophthalmic (OA) arteries were measured before, 2 days, 3 weeks and 6 months after the first injection. Patients were examined monthly and received 1-5 additional injections depending on ophthalmologic examination results. RESULTS: Six months after the first injection, a significant increase in visual acuity 50.9 ± 25.9 versus 44.4 ± 21.7 (p < 0.01) and decrease in mean central macular thickness 267 ± 74 versus 377 ± 115 µm (p < 0.001) were observed compared to baseline. Although mean-BFVs decreased by 16%±3% in CRA and 20%±5% in TPCA (p < 0.001) 2 days after the first injection, no significant change was seen thereafter. Mean-BFVs in OA decreased by 19%±5% at week 3 (p < 0.001). However, the smallest number of injections (two injections) was associated with the longest time interval between the last injection and month 6 (20 weeks) and with the best return to baseline levels for mean-BFVs in CRA, suggesting that ranibizumab had reversible effects on native retinal vascular supply after its discontinuation. Moreover, a significant correlation between the number of injections and percentage of changes in mean-BFVs in CRA was observed at month 6 (R = 0.74, p < 0.001) unlike TPCA or OA. CONCLUSION: Ranibizumab could impair the native choroidal and retinal vascular networks, but its effect seems reversible after its discontinuation.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Artérias Ciliares/fisiologia , Artéria Oftálmica/fisiologia , Artéria Retiniana/fisiologia , Degeneração Macular Exsudativa/tratamento farmacológico , Degeneração Macular Exsudativa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Feminino , Humanos , Pressão Intraocular , Injeções Intravítreas , Masculino , Estudos Prospectivos , Ranibizumab , Fluxo Sanguíneo Regional , Retratamento , Ultrassonografia Doppler em Cores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual
13.
J Clin Invest ; 124(7): 3230-40, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24937433

RESUMO

Autonomic sympathetic nerves innervate peripheral resistance arteries, thereby regulating vascular tone and controlling blood supply to organs. Despite the fundamental importance of blood flow control, how sympathetic arterial innervation develops remains largely unknown. Here, we identified the axon guidance cue netrin-1 as an essential factor required for development of arterial innervation in mice. Netrin-1 was produced by arterial smooth muscle cells (SMCs) at the onset of innervation, and arterial innervation required the interaction of netrin-1 with its receptor, deleted in colorectal cancer (DCC), on sympathetic growth cones. Function-blocking approaches, including cell type-specific deletion of the genes encoding Ntn1 in SMCs and Dcc in sympathetic neurons, led to severe and selective reduction of sympathetic innervation and to defective vasoconstriction in resistance arteries. These findings indicate that netrin-1 and DCC are critical for the control of arterial innervation and blood flow regulation in peripheral organs.


Assuntos
Artérias Mesentéricas/inervação , Fatores de Crescimento Neural/fisiologia , Sistema Nervoso Simpático/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Animais Recém-Nascidos , Receptor DCC , Feminino , Cones de Crescimento/fisiologia , Masculino , Artérias Mesentéricas/crescimento & desenvolvimento , Artérias Mesentéricas/fisiologia , Camundongos , Camundongos Knockout , Camundongos Mutantes , Camundongos Transgênicos , Modelos Neurológicos , Miócitos de Músculo Liso/fisiologia , Fatores de Crescimento Neural/deficiência , Fatores de Crescimento Neural/genética , Netrina-1 , Gravidez , Receptores de Superfície Celular/fisiologia , Sistema Nervoso Simpático/crescimento & desenvolvimento , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética , Vasoconstrição/fisiologia
14.
Stem Cells ; 32(1): 231-43, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24105925

RESUMO

Upregulation of hypoxia-inducible transcription factor-1α (HIF-1α), through prolyl-hydroxylase domain protein (PHD) inhibition, can be thought of as a master switch that coordinates the expression of a wide repertoire of genes involved in regulating vascular growth and remodeling. We aimed to unravel the effect of specific PHD2 isoform silencing in cell-based strategies designed to promote therapeutic revascularization in patients with critical limb ischemia (CLI). PHD2 mRNA levels were upregulated whereas that of HIF-1α were downregulated in blood cells from patients with CLI. We therefore assessed the putative beneficial effects of PHD2 silencing on human bone marrow-derived mesenchymal stem cells (hBM-MSC)-based therapy. PHD2 silencing enhanced hBM-MSC therapeutic effect in an experimental model of CLI in Nude mice, through an upregulation of HIF-1α and its target gene, VEGF-A. In addition, PHD2-transfected hBM-MSC displayed higher protection against apoptosis in vitro and increased rate of survival in the ischemic tissue, as assessed by Fluorescence Molecular Tomography. Cotransfection with HIF-1α or VEGF-A short interfering RNAs fully abrogated the beneficial effect of PHD2 silencing on the proangiogenic capacity of hBM-MSC. We finally investigated the effect of PHD2 inhibition on the revascularization potential of ischemic targeted tissues in the diabetic pathological context. Inhibition of PHD-2 with shRNAs increased postischemic neovascularization in diabetic mice with CLI. This increase was associated with an upregulation of proangiogenic and proarteriogenic factors and was blunted by concomitant silencing of HIF-1α. In conclusion, silencing of PHD2, by the transient upregulation of HIF-1α and its target gene VEGF-A, might improve the efficiency of hBM-MSC-based therapies.


Assuntos
Transplante de Células/métodos , Membro Posterior/irrigação sanguínea , Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Isquemia/terapia , Células-Tronco Mesenquimais/citologia , Inibidores de Prolil-Hidrolase/uso terapêutico , Idoso , Animais , Apoptose/fisiologia , Estudos de Casos e Controles , Modelos Animais de Doenças , Procedimentos Endovasculares/métodos , Humanos , Isquemia/enzimologia , Salvamento de Membro/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Pessoa de Meia-Idade , Transfecção
15.
J Surg Res ; 184(2): 888-97, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23726239

RESUMO

BACKGROUND: Hepatic pedicle clamping is often required to reduce blood loss and transfusion during liver resection. However, the question remains whether use of hepatic pedicle clamping promotes tumor growth. Endothelial progenitor cells (EPCs) are mobilized from bone marrow in response to tissue ischemia, which allows neovascularization of ischemic tissue. It has been suggested that EPCs are involved in tumor progression. We hypothesized that hepatic ischemia reperfusion (I/R)-induced mobilization of EPCs could enhance growth of microscopic tumor, therefore promoting liver metastasis in a mouse model of colorectal cancer. MATERIALS AND METHODS: We used mouse models of hepatic I/R and hind limb ischemia. For comparison, we studied mice that underwent limb ischemia as positive controls of EPC mobilization. At day 0, we divided 40 mice into four groups: hepatic I/R, hind limb ischemia, combined hepatic I/R and hind limb ischemia, and control (sham midline incision laparotomy). At day 2, we induced liver metastasis in all mice by injecting CT-26 cells into the spleen. Time-dependent circulating EPCs were determined by flow cytometry. We evaluated liver metastasis and microvascular density on day 21. RESULTS: The number of circulating progenitor cells increased rapidly in the ischemic groups compared with the control group. Hepatic I/R significantly increased tumor outgrowth compared with the control group. Increased tumor growth was associated with enhanced CD31-positive microvascular density in liver tissue. CONCLUSIONS: Hepatic I/R leads to mobilization of bone marrow-derived EPCs and enhanced intra-hepatic angiogenesis, which is associated with increased tumor burden in an animal model of colorectal liver metastasis.


Assuntos
Células da Medula Óssea/patologia , Proliferação de Células , Neoplasias Colorretais/patologia , Células-Tronco Hematopoéticas/patologia , Neoplasias Hepáticas/secundário , Fígado/irrigação sanguínea , Traumatismo por Reperfusão/fisiopatologia , Animais , Contagem de Células , Linhagem Celular Tumoral , Quimiocina CXCL12/sangue , Modelos Animais de Doenças , Progressão da Doença , Feminino , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica/fisiopatologia , Neovascularização Patológica/fisiopatologia
16.
Genes Immun ; 14(4): 258-67, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23615071

RESUMO

Gold or mercury salts trigger a dramatic IgE response and a CD4 T-cell-dependent nephropathy in Brown-Norway (BN), but not in Lewis (LEW) rats. We previously identified the 1.1-Mb Iresp3 (immunoglobin response QTL3) locus on chromosome 9 that controls these gold salt-triggered immune disorders. In the present work, we investigated the genetic control of HgCl(2)-induced immunological disorders and assessed the relative contribution of the CD45RC(high) and CD45RC(low) CD4 T-cell subpopulations in this control. By using interval-specific congenic lines, we narrowed down Iresp3 locus to 117-kb and showed that BN rats congenic for the LEW 117-kb were protected from HgCl(2)-triggered IgE response and nephropathy. This 117-kb interval also controls CD45RC expression by CD4 T cells and the ability of CD45RC(high) CD4 T cells to trigger the autoimmune disorders resulting from HgCl(2) administration. This 117-kb region contains four genes, including Vav1, a strong candidate gene according to its cellular function and exclusive expression in hematopoietic cells. Thus, this study highlights the role of the CD45RC(high) CD4 T-cell subpopulation in the opposite susceptibility of BN and LEW rats to HgCl(2)-triggered immune disorders and identifies a 117-kb interval on chromosome 9 that has a key role in their functions.


Assuntos
Autoimunidade/genética , Linfócitos T CD4-Positivos/imunologia , Loci Gênicos , Imunoglobulina E/genética , Animais , Doenças Autoimunes/induzido quimicamente , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Linfócitos T CD4-Positivos/metabolismo , Cromossomos de Mamíferos/genética , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/metabolismo , Cloreto de Mercúrio/toxicidade , Nefrite/induzido quimicamente , Nefrite/genética , Nefrite/imunologia , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew
17.
J Crohns Colitis ; 7(6): 451-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22841134

RESUMO

BACKGROUND AND AIMS: Active Crohn's disease affects intestine but may alter other locations as eyes vasculature. Previous studies provide evidence of elevated blood flow velocities (BFv) and volume (BFV) in superior mesenteric artery (SMA). We prospectively studied hemodynamics in feeding arteries of bowel and eyes before and 2 weeks after treatment induction with anti-TNFα. METHODS: Fifteen patients (5 females, 10 males, 35.4 ± 9.0 years, mean ± SD) with active Crohn's disease for 7.5 ± 7.7 years were enrolled. Ultrasound imaging was performed before and 2 weeks after treatment in SMA and retrobulbar arteries: central retinal (CRA), temporal posterior ciliary (TPCA) and ophthalmic (OA) arteries. Serum markers of inflammation (CRP and fibrinogen), arterial blood pressures (ABP) and skin flow-mediated dilation (sFMD) were measured and patients were compared to 10 control age- and sex-matched subjects. RESULTS: Before treatment, CRP and fibrinogen plasma concentrations, SMA BFV (339 ± 100 mL/min) were higher in patients than in controls by 8.5-fold (p<0.001), 1.4-fold (p<0.01) and 1.5-fold, respectively (p<0.01). BFv in CRA (3.5 ± 0.7 cm/s) and TPCA (4.4 ± 1.0 cm/s), sFMD (371 ± 469%) were significantly lower than in controls by 83%, 73% and 52% respectively (p<0.05). Two weeks after treatment, CRP and fibrinogen decreased, SMA BFV was normalized (230 ± 39L/min, p<0.01), BFv in CRA, TPCA and OA increased respectively to 4.0 ± 1.1 (p<0.05), 5.2 ± 1.4 (p<0.001), 8.9 ± 3 cm/s (p<0.05). ABP and sFMD remained unchanged. CONCLUSIONS: In active Crohn's disease, a first anti-TNFα administration rapidly normalized concomitantly plasma inflammatory markers and blood-flows in the mesenteric and retrobulbar arteries without affecting blood pressure and endothelial function.


Assuntos
Artérias Ciliares/diagnóstico por imagem , Fármacos Gastrointestinais/uso terapêutico , Artéria Mesentérica Superior/diagnóstico por imagem , Artéria Oftálmica/diagnóstico por imagem , Artéria Retiniana/diagnóstico por imagem , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab , Adulto , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Volume Sanguíneo/efeitos dos fármacos , Proteína C-Reativa/análise , Estudos de Casos e Controles , Doença de Crohn/tratamento farmacológico , Feminino , Fibrinogênio/análise , Humanos , Infliximab , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia Doppler em Cores , Adulto Jovem
18.
J Neuroimmunol ; 254(1-2): 55-62, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23026222

RESUMO

Inflammation plays a key role in ischemic stroke pathophysiology: microglial/macrophage cells and type-1 helper cells (Th1) seem deleterious, while type-2 helper cells (Th2) and regulatory T cells (Treg) seem protective. CD4 Th0 differentiation is modulated by microglial cytokine secretion. Glatiramer Acetate (GA) is an immunomodulatory drug that has been approved for the treatment of human multiple sclerosis by means of a number of mechanisms: reduced microglial activation and pro-inflammatory cytokine production, Th0 differentiation shifting from Th2 to Th2 and Treg with anti-inflammatory cytokine production and increased neurogenesis. We induced permanent (pMCAo) or transient middle cerebral artery occlusion (tMCAo) and GA (2 mg) or vehicle was injected subcutaneously immediately after cerebral ischemia. Mice were sacrificed at D3 to measure neurological deficit, infarct volume, microglial cell density and qPCR of TNFα and IL-1ß (pro-inflammatory microglial cytokines), IFNγ (Th2 cytokine), IL-4 (Th2 cytokine), TGFß and IL-10 (Treg cytokines), and at D7 to evaluate neurological deficit, infarct volume and neurogenesis assessment. We showed that in GA-treated pMCAo mice, infarct volume, microglial cell density and cytokine secretion were not significantly modified at D3, while neurogenesis was enhanced at D7 without significant infarct volume reduction. In GA-treated tMCAo mice, microglial pro-inflammatory cytokines IL-1ß and TNFα were significantly decreased without modification of microglial/macrophage cell density, cytokine secretion, neurological deficit or infarct volume at D3, or modification of neurological deficit, neurogenesis or infarct volume at D7. In conclusion, Glatiramer Acetate administered after cerebral ischemia does not reduce infarct volume or improve neurological deficit in mice despite a significant increase in neurogenesis in pMCAo and a microglial pro-inflammatory cytokine reduction in tMCAo.


Assuntos
Infarto Encefálico/tratamento farmacológico , Infarto Encefálico/etiologia , Imunossupressores/administração & dosagem , Infarto da Artéria Cerebral Média/complicações , Peptídeos/administração & dosagem , Animais , Infarto Encefálico/mortalidade , Bromodesoxiuridina/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Proteínas do Domínio Duplacortina , Acetato de Glatiramer , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/mortalidade , Injeções Subcutâneas , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Neurogênese/efeitos dos fármacos , Exame Neurológico , Neuropeptídeos/metabolismo , RNA Mensageiro , Estatísticas não Paramétricas , Linfócitos T/classificação , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Fatores de Tempo
19.
Ann Pharmacother ; 46(12): e38, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23191934

RESUMO

OBJECTIVE: To report a case of refractory nausea in a patient with idiopathic gastroparesis successfully treated with aprepitant. CASE SUMMARY: A 41-year-old female with idiopathic gastroparesis demonstrated by a delayed gastric emptying time experienced significant nausea, vomiting, and abdominal pain. This resulted in numerous hospital admissions and regular outpatient intravenous fluid administration. Over a 3-year period the patient had been treated with numerous agents for nausea and vomiting, including metoclopramide 10 mg 3 times daily, ondansetron 8 mg 2 times daily, and promethazine (various doses from 12.5 to 25 mg orally up to 3 times daily). No treatment tried was either tolerated or effective. As a last option before considering gastric pacing the patient was started on aprepitant 40 mg daily. The patient had a dramatic response to aprepitant and reported that her nausea had decreased significantly after 48 hours of starting the medication (2 doses). She was able to tolerate oral feeding and her need for outpatient intravenous hydration abated. Over the course of 2 months while using aprepitant her gastroparesis symptoms continued to improve. She reported no adverse effects attributable to aprepitant. After the first 2 months of aprepitant treatment, the patient was unable to continue the medication due to cost. Although her symptoms did worsen after discontinuation, they did not return to their initial severity. At 4 months after the trial of aprepitant, she continued to have improved symptoms. She claimed not to have daily nausea or vomiting, but still required high-dose promethazine and occasional outpatient intravenous fluids. At that point, she had gained 7.2 kg from the time that she had started aprepitant. DISCUSSION: Aprepitant, a neurokinin-1 receptor antagonist, is approved in the US for nausea and vomiting associated with surgery and cancer chemotherapy. To our knowledge, this is the second reported case of its use in gastroparesis-induced nausea. Our patient reported relief of nausea and vomiting despite existing evidence showing that aprepitant has no significant effect on accelerating gastric emptying. Despite its acquisition cost, our patient avoided hospital admission and the administration of intravenous hydration, suggesting aprepitant may be cost-effective in this case. CONCLUSIONS: Aprepitant may have some utility in treating refractory nausea caused by gastroparesis. This case suggests that the drug's antiemetic effect may be successfully used in areas not approved by the Food and Drug Administration. A controlled trial examining aprepitant in patients with such challenging clinical conditions may be warranted.


Assuntos
Antieméticos/uso terapêutico , Morfolinas/uso terapêutico , Náusea/tratamento farmacológico , Vômito/tratamento farmacológico , Dor Abdominal/etiologia , Adulto , Antieméticos/administração & dosagem , Aprepitanto , Feminino , Seguimentos , Gastroparesia/complicações , Gastroparesia/tratamento farmacológico , Humanos , Morfolinas/administração & dosagem , Náusea/etiologia , Antagonistas dos Receptores de Neurocinina-1 , Prometazina/administração & dosagem , Prometazina/uso terapêutico , Resultado do Tratamento , Vômito/etiologia
20.
Eur J Neurosci ; 35(8): 1208-17, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22512253

RESUMO

Pro-angiogenic cell-based therapies constitute an interesting and attractive approach to enhancing post-stroke neurogenesis and decreasing neurological deficit. However, most new stroke-induced neurons die during the first few weeks after ischemia, thus impairing total recovery. Although the neovascularization process involves different cell types and various growth factors, most cell therapy protocols are based on the biological effects of single-cell-type populations or on the administration of heterogeneous populations of progenitors, namely human cord blood-derived CD34(+) cells, with scarce vascular progenitor cells. Tight cooperation between endothelial cells and smooth muscle cells/pericytes is critical for the development of functional neovessels. We hypothesized that neuroblast survival in stroke brain depends on mature vascular network formation. In this study, we injected a combination of endothelial progenitor cells (EPCs) and smooth muscle progenitor cells (SMPCs), isolated from human umbilical cord blood, into a murine model of permanent focal ischemia induced by middle cerebral artery occlusion. The co-administration of SMPCs and EPCs induced enhanced angiogenesis and vascular remodeling in the peri-infarct and infarct areas, where vessels exhibited a more mature phenotype. This activation of vessel growth resulted in the maintenance of neurogenesis and neuroblast migration to the peri-ischemic cortex. Our data suggest that a mature vascular network is essential for neuroblast survival after cerebral ischemia, and that co-administration of EPCs and SMPCs may constitute a novel therapeutic strategy for improving the treatment of stroke.


Assuntos
Células Endoteliais/transplante , Infarto da Artéria Cerebral Média/terapia , Miócitos de Músculo Liso/transplante , Neovascularização Fisiológica/fisiologia , Neurogênese/fisiologia , Células-Tronco , Inibidores da Angiogênese/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Bromodesoxiuridina/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Endostatinas/farmacologia , Células Endoteliais/fisiologia , Sangue Fetal/citologia , Receptores Frizzled/metabolismo , Lateralidade Funcional , Humanos , Marcação In Situ das Extremidades Cortadas/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Miócitos de Músculo Liso/fisiologia , Neovascularização Patológica/etiologia , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Neurogênese/efeitos dos fármacos , Peptídeos/genética , Peptídeos/metabolismo , Permeabilidade/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Tempo
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