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1.
Clin Ter ; 171(4): e340-e345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614369

RESUMO

BACKGROUND AND AIMS: Elderly may suffer from different pathologies during their detention in jail because of their age. Conditions in jails were tough and adapting to that life could be problematic for the elder population. This article aimed to analyse the pathologies and health conditions in a sample of elder inmates from Italy. METHODS: The sample was composed by 94 elderly inmates. The research is multicentric. We selected jails from the cities of Bari, Taranto, Foggia, Lecce, Brescia, Bergamo, Cremona and Mantua. The study was conducted by interviewing the prisoners over 60 years of age, in the period between September and December 2017. RESULTS: 64% of the sample was in a "Not Optimal" health status. Most of pathologies were Cardiac pathologies (23.4%), Diabetes (12.8 %) and Surgery (9.6%). Statistically significant differences were found for heart disease (p=0.02) and Neoplasia (p=0.025) in the prison of Bari compared to all the other prisons. Statistically significant differences were found for Hypertension in Foggia and Taranto prisons compared to all the other (p=0.023). Furthermore, 18.1% of inmates ended up having an addiction. CONCLUSIONS: Our analysis showed that in our sample physical problems were more frequent than psychological one. In fact, in spite of in the literature there was a high prevalence of mental health problems among elderly inmates, we did not find this result. However, stress conditions may increase the risk of pathologies: for example, being in jail and adapt to new hard environment may increase the risk of getting sick. Heart disease pathologies and diabetes were very common in our sample as confirmed by the literature.


Assuntos
Envelhecimento , Nível de Saúde , Prisioneiros , Idoso , Estudos Transversais , Doença , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estresse Psicológico
2.
Biochemistry (Mosc) ; 84(12): 1442-1450, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31870248

RESUMO

The theories interpreting senescence as a phenomenon favored by natural selection require the existence of specific, genetically determined and regulated mechanisms that cause a progressive age-related increase in mortality. The mechanisms defined in the subtelomere-telomere theory suggest that progressive slackening of cell turnover and decline in cellular functions are determined by the subtelomere-telomere-telomerase system, which causes a progressive "atrophic syndrome" in all organs and tissues. If the mechanisms underlying aging-related dysfunctions are similar and having the same origin, it could be hypothesized that equal interventions could produce similar effects. This article reviews the consequences of some factors (diabetes, obesity/dyslipidemia, hypertension, smoking, moderate use and abuse of alcohol) and classes of drugs [statins, angiotensin-converting enzyme (ACE) inhibitors, sartans] in accelerating and anticipating or in counteracting the process of aging. The evidence is compatible with the programmed aging paradigm and the mechanisms defined by the subtelomere-telomere theory but it has no obvious discriminating value against the theories of non-programmed aging paradigm. However, the existence of mechanisms, determined by the subtelomere-telomere-telomerase system and causing a progressive age-related decline in fitness through gradual cell senescence and cell senescence, is not justifiable without an evolutionary motivation. Their existence is expected by the programmed aging paradigm, while is incompatible with the opposite paradigm.


Assuntos
Envelhecimento/patologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Modelos Teóricos , Fatores de Risco , Telômero/efeitos dos fármacos
3.
Biochemistry (Mosc) ; 83(12): 1477-1488, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30878023

RESUMO

Cell senescence is an artificially reversible condition activated by various factors and characterized by replicative senescence and typical general alteration of cell functions, including extra-cellular secretion. The number of senescent cells increases with age and contributes strongly to the manifestations of aging. For these reasons, research is under way to obtain "senolytic" compounds, defined as drugs that eliminate senescent cells and therefore reduce aging-associated decay, as already shown in some experiments on animal models. This objective is analyzed in the context of the programmed aging paradigm, as described by the mechanisms of the subtelomere-telomere theory. In this regard, positive effects of the elimination of senescent cells and limits of this method are discussed. For comparison, positive effects and limits of telomerase activation are also analyzed, as well of the combined action of the two methods and the possible association of opportune gene modifications. Ethical issues associated with the use of these methods are outlined.


Assuntos
Senescência Celular/genética , Telômero/genética , Animais , Senescência Celular/efeitos dos fármacos , Humanos , Modelos Biológicos , Neoplasias/genética , Neoplasias/patologia , Risco
4.
Transl Med UniSa ; 16: 24-29, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28775966

RESUMO

Although there is evidence of a growing awareness of the problem, no official policy statements or regulatory guidelines on polypharmacy have been released up to date by Italian Health Authorities. Medication review, application of appropriateness criteria and computerized prescription support systems are all possible approaches in order to improve the quality of prescribing in older persons. More focused training courses on multimorbidity and polytherapy management are encouraged. Furthermore a multidisciplinary approach integrating different health care professionals (physicians, pharmacists, and nurses) may positively impact on reducing the sense of fear related to discontinue or substitute drugs prescribed by others; the fragmentation of therapy among different specialists; reducing costs; and improving adverse drug reaction detection and reporting. Aiming at achieving the individualized pharmacotherapy, a multidisciplinary approach starting with identification of patients and risk for drug-related problems, followed by medication review overtime and use of inappropriateness criteria, supported by computerized systems has been proposed.

5.
Nutr Metab Cardiovasc Dis ; 25(6): 519-25, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25816732

RESUMO

AIMS: Biologically active phenomena, triggered by atherogenesis and inflammation, lead to aortic valve (AV) calcification. Lipids play an important role in activating the cell signaling leading to AV bone deposition. This review, based on evidence from animal and human studies, mainly focused on the involvement of lipids and atherogenic phenomena in the pathogenesis of calcific aortic stenosis (AS). DATA SYNTHESIS: The role of elevated low density lipoproteins for the risk of both vascular atherosclerosis and AS has been elucidated. Lipid disorders act synergistically with other risk factors to increase prevalence of calcific AS. Atherosclerosis is also involved in the pathogenesis of bone demineralization, a typical hallmark of aging, which is associated with ectopic calcification at vascular and valvular levels. Animal studies have recently contributed to demonstrate that lipids play an important role in AS pathogenesis through the activation of molecular cell signalings, such as Wnt/Lrp5 and RANK/RANKL/Osteprotegerin, which induce the transition of valvular myofibroblasts toward an osteogenic phenotype with consequent valvular bone deposition. Although all these evidence strongly support the lipid theory in AS pathogenesis, lipids lowering therapies failed to demonstrate in controlled trials a significant efficacy to slow AS progression. Encouraging results from animal studies indicate that physical activity may counteract the biological processes inducing AV degeneration. CONCLUSIONS: This review indicates a robust interplay between lipids, inflammation, and calcific AS. This new pathophysiological scenario of such an emerging valvular disease paves the way to the next challenge of cardiovascular research: "prevent and care aortic valve stenosis".


Assuntos
Estenose da Valva Aórtica/etiologia , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Aterosclerose/complicações , Calcinose/etiologia , Metabolismo dos Lipídeos , Animais , Valva Aórtica/efeitos dos fármacos , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/tratamento farmacológico , Estenose da Valva Aórtica/metabolismo , Aterosclerose/diagnóstico , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Remodelação Óssea , Calcinose/diagnóstico , Calcinose/tratamento farmacológico , Calcinose/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Mediadores da Inflamação/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fatores de Risco , Transdução de Sinais
6.
Br J Pharmacol ; 166(8): 2348-61, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22452704

RESUMO

BACKGROUND AND PURPOSE: We investigated whether ß(2) -adrenoceptor overexpression could promote angiogenesis and improve blood perfusion and left ventricular (LV) remodeling of the failing heart. EXPERIMENTAL APPROACH: We explored the angiogenic effects of ß(2) -adrenoceptor overexpression in a rat model of post-myocardial infarction (MI) heart failure (HF). Cardiac adenoviral-mediated ß(2) -adrenoceptor overexpression was obtained via direct intramyocardial injection 4-weeks post-MI. Adenovirus(Ad)-GFP and saline injected rats served as controls. Furthermore, we extended our observation to ß(2) -adrenoceptor -/- mice undergoing MI. KEY RESULTS: Transgenes were robustly expressed in the LV at 2 weeks post-gene therapy, whereas their expression was minimal at 4-weeks post-gene delivery. In HF rats, cardiac ß(2) -adrenoceptor overexpression resulted in enhanced basal and isoprenaline-stimulated cardiac contractility at 2-weeks post-gene delivery. At 4 weeks post-gene transfer, Ad-ß(2) -adrenoceptor HF rats showed improved LV remodeling and cardiac function. Importantly, ß(2) -adrenoceptor overexpression was associated with a markedly increased capillary and arteriolar length density and enhanced in vivo myocardial blood flow and coronary reserve. At the molecular level, cardiac ß(2) -adrenoceptor gene transfer induced the activation of the VEGF/PKB/eNOS pro-angiogenic pathway. In ß(2) -adrenoceptor-/- mice, we found a ~25% reduction in cardiac capillary density compared with ß(2) -adrenoceptor+/+ mice. The lack of ß(2) -adrenoceptors was associated with a higher mortality rate at 30 days and LV dilatation, and a worse global cardiac contractility compared with controls. CONCLUSIONS AND IMPLICATION: ß(2) -Adrenoceptors play an important role in the regulation of the angiogenic response in HF. The activation of VEGF/PKB/eNOS pathway seems to be strongly involved in this mechanism.


Assuntos
Terapia Genética/métodos , Receptores Adrenérgicos beta 2/genética , Animais , Regulação da Expressão Gênica , Técnicas de Transferência de Genes , Camundongos , Camundongos Knockout , Contração Miocárdica , Reperfusão Miocárdica , Miocárdio , Neovascularização Fisiológica , Ratos , Remodelação Ventricular
7.
Clin Exp Rheumatol ; 27(6): 977-80, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20149315

RESUMO

OBJECTIVES: To assess the validity of the BASRI and m-SASSS scores for the radiological axial involvement in psoriatic arthritis (PsA). Secondary end-points were to report on clinical, functional and radiographic characteristics of axial involvement. METHODS: Inclusion criteria were satisfaction of the CASPAR criteria and the presence of clinical, functional and/or radiological axial involvement. Three observers scored the radiographs by BASRI and m-SASSS. The construct validity was assessed by examining the correlation of instruments with patient reported outcomes and anthropometric measures. The reliability and the feasibility of the scores were also considered. RESULTS: Seventy-seven patients were enrolled (58 M, 19 F, mean age 49.4 + or - 10.8 yrs, disease duration 13.9 + or - 7.9 yrs). Both instruments showed some modest but significant correlation with clinical measures. When compared, the BASRI showed a correlation with BASMI (rho=0.47, p<0.001), cervical rotation (rho=-0.49, p<0.001), tragus to wall (rho=0.34, p<0.01) and occiput to wall (rho=0.49, p<0.001), modified Schober test (rho=-0.24, p<0.05) and RLDQ (rho=-0.24, p<0.05). When compared, m-SASSS showed a correlation with BASMI (rho=0.39, p<0.001), cervical rotation (rho=-0.41, p<0.001), tragus to wall (rho=0.31, p<0.01) and occiput to wall (rho=0.42, p<0.001), modified Schober and Schober test (rho=-0.34, p<0.001; rho= -0.32, p<0.01), finger to floor (rho=0.37, p<0.01). No correlation was found with BASFI, BASDAI and HAQ. Test-retest showed a good reliability of the scores. Both were feasible but BASRI was the quickest. CONCLUSION: Our results showed that BASRI and m-SASSS were valid instruments for use in spondylitis associated with psoriatic arthritis. Longitudinal data is required to provide sensitivity to change of the two scores.


Assuntos
Artrite Psoriásica/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Espondilite/diagnóstico por imagem , Adulto , Artrite Psoriásica/complicações , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Radiografia , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Espondilite/complicações , Inquéritos e Questionários
8.
Exp Clin Endocrinol Diabetes ; 116 Suppl 1: S46-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18777454

RESUMO

Mice, deficient for vascular endothelial growth factor VEGF-A in pancreatic islets, have reduced insulin gene expression levels and an impaired glucose tolerance. Here, we investigated whether VEGF-A was required for physiological glucose-stimulated insulin secretion and insulin content. We performed in situ pancreas perfusions and islet perifusions on mice lacking VEGF-A in the pancreatic epithelium in order to study their ability to secrete insulin in response to glucose. We identified insulin secretion defects in the pancreata of VEGF-A deficient mice, including a delayed and blunted response to glucose. Islet perifusion experiments revealed a missing first phase and weaker second phase of insulin secretion, in two of three VEGF-A deficient mice. On average, insulin content in VEGF-A deficient islets was significantly reduced when compared with control islets. We conclude that VEGF-A is required in pancreatic islets for normal glucose-stimulated insulin secretion and physiological insulin content. Thus, VEGF-A is a key factor for pancreatic islet function.


Assuntos
Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Arginina/farmacologia , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Glucose/farmacologia , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/fisiologia , Camundongos , Camundongos Knockout , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Diabetologia ; 50(2): 380-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17180351

RESUMO

AIMS/HYPOTHESIS: Endothelial cells are considered to be essential for normal pancreatic beta cell function. However, there have been no reports showing their importance for beta cell function. MATERIALS AND METHODS: Using mice with disrupted vascular endothelial growth factor-A gene specifically in beta cells, we investigated the relation between islet vascular structure and beta cell function. RESULTS: Mice with disrupted vascular endothelial growth factor-A gene specifically in beta cells had reduced islet vascular density with impaired formation of endothelial fenestration. While their fasting glucose and body weight were comparable with control mice, their glucose- and tolbutamide-induced rapid insulin release were impaired, thus resulting in glucose intolerance. On the other hand, glucose and KCl enhanced the levels of insulin secreted from islets isolated from these mice. In addition, the production of soluble N-ethylmaleimide-sensitive factor attachment protein receptors in the islets was increased. Insulin content and expression of insulin I and pancreas duodenum homeobox 1 mRNA in the islets were also increased. CONCLUSIONS/INTERPRETATION: Our results indicate that an abnormal quality and quantity of blood vessels due to reduced expression of vascular endothelial growth factor-A in beta cells could be a cause of impaired insulin secretion without impairment of beta cell function.


Assuntos
Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Fator A de Crescimento do Endotélio Vascular/deficiência , Animais , Glicemia/metabolismo , Cruzamentos Genéticos , Endotélio Vascular/fisiologia , Feminino , Secreção de Insulina , Células Secretoras de Insulina/fisiologia , Ilhotas Pancreáticas/irrigação sanguínea , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , RNA/genética , RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular/genética
10.
Exp Clin Endocrinol Diabetes ; 111(4): 209-14, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12845559

RESUMO

Vascular endothelial growth factor (VEGF) has been shown to play a major role in intraocular neovascularisation in ischaemic retinal diseases. The aim of this study was to evaluate the concentration of VEGF in vitreous, aqueous and epiretinal membranes of diabetic and non-diabetic patients, with other pathological conditions requiring surgical intervention. Higher VEGF concentration were found in samples from the eyes of diabetic patients versus other pathologies as well as in epiretinal membranes versus the other eye compartments in diabetic patients. However, high VEGF levels were also found in retinal detachment and proliferative vitreoretinopathy of non-diabetic patients. We concluded that VEGF is produced locally and plays a fundamental, but not specific, role in diabetic retinal neovascularisation and proliferation.


Assuntos
Retinopatia Diabética/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Humor Aquoso/metabolismo , Diabetes Mellitus Tipo 2 , Retinopatia Diabética/complicações , Retinopatia Diabética/patologia , Retinopatia Diabética/cirurgia , Membrana Epirretiniana/metabolismo , Oftalmopatias/metabolismo , Feminino , Humanos , Hipertensão/complicações , Hipertensão/metabolismo , Fotocoagulação , Macula Lutea , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Período Pós-Operatório , Retina/metabolismo , Retina/patologia , Descolamento Retiniano/complicações , Descolamento Retiniano/metabolismo , Doenças Retinianas/metabolismo , Neovascularização Retiniana/metabolismo , Perfurações Retinianas/metabolismo , Distribuição Tecidual , Fator A de Crescimento do Endotélio Vascular/sangue , Vitrectomia , Vitreorretinopatia Proliferativa/complicações , Vitreorretinopatia Proliferativa/metabolismo , Corpo Vítreo/metabolismo
12.
J Magn Reson Imaging ; 14(4): 374-82, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11599061

RESUMO

A mouse model of non-necrotic vascular deficiency in the adult heart was studied using cine-magnetic resonance imaging (MRI) and other techniques. The mice lacked cardiomyocyte-derived vascular endothelial growth factor (VEGF) following a targeted knockout in the ventricular cardiomyocytes. Quantitative endothelial labeling showed that the capillary density was significantly reduced in the hearts of knockout mice. Gene expression patterns suggested that they were hypoxic. Semiautomated MR image analysis was employed to obtain both global and regional measurements of left ventricular function at 10 or more time points through the cardiac cycle. MRI measurements showed a marked reduction in ejection fraction both at rest and under low- and high-dose dobutamine stress. Regional wall thickness, thickening, and displacement were all attenuated in the knockout mice. A prolonged high-dose dobutamine challenge was monitored by MRI. A maximal response was sustained for 90 minutes, suggesting that it did not depend on endogenous glycogen stores.


Assuntos
Dobutamina , Fatores de Crescimento Endotelial/fisiologia , Coração/fisiologia , Linfocinas/fisiologia , Imagem Cinética por Ressonância Magnética/métodos , Animais , Peso Corporal , Capilares/anatomia & histologia , Fatores de Crescimento Endotelial/genética , Expressão Gênica , Linfocinas/genética , Camundongos , Camundongos Knockout , Modelos Teóricos , Miocárdio/patologia , RNA Mensageiro/análise , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
13.
J Virol ; 75(20): 9828-35, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11559816

RESUMO

This report analyzes the role of vascular endothelial growth factor (VEGF)-induced angiogenesis in the immunoinflammatory lesion stromal keratitis induced by ocular infection with herpes simplex virus (HSV). Our results show that infection with replication-competent, but not mutant, viruses results in the expression of VEGF mRNA and protein in the cornea. This a rapid event, with VEGF mRNA detectable by 12 h postinfection (p.i.) and proteins detectable by 24 h p.i. VEGF production occurred both in the virus-infected corneal epithelium and in the underlying stroma, in which viral antigens were undetectable. In the stroma, VEGF was produced by inflammatory cells; these initially were predominantly polymorphonuclear leukocytes (PMN), but at later time points both PMN and macrophage-like cells were VEGF producers. In the epithelium, the major site of VEGF-expressing cells in early infection, the infected cells themselves were usually negative for VEGF. Similarly, in vitro infection studies indicated that the cells which produced VEGF were not those which expressed virus. Attesting to the possible role of VEGF-induced angiogenesis in the pathogenesis of herpetic stromal keratitis were experiments showing that VEGF inhibition with mFlt(1-3)-immunoglobulin G diminished angiogenesis and the severity of lesions after HSV infection. These observations are the first to evaluate VEGF-induced angiogenesis in the pathogenesis of stromal keratitis. Our results indicate that the control of angiogenesis represents a useful adjunct to therapy of herpetic ocular disease, an important cause of human blindness.


Assuntos
Neovascularização da Córnea/etiologia , Fatores de Crescimento Endotelial/biossíntese , Ceratite Herpética/complicações , Linfocinas/biossíntese , Simplexvirus , Animais , Neovascularização da Córnea/prevenção & controle , Substância Própria/metabolismo , Fatores de Crescimento Endotelial/antagonistas & inibidores , Ensaio de Imunoadsorção Enzimática , Epitélio Corneano/metabolismo , Epitélio Corneano/virologia , Feminino , Ceratite Herpética/tratamento farmacológico , Ceratite Herpética/virologia , Linfocinas/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos BALB C , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Simplexvirus/isolamento & purificação , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
14.
Nature ; 412(6850): 877-84, 2001 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-11528470

RESUMO

The known endothelial mitogens stimulate growth of vascular endothelial cells without regard to their tissue of origin. Here we report a growth factor that is expressed largely in one type of tissue and acts selectively on one type of endothelium. This molecule, called endocrine-gland-derived vascular endothelial growth factor (EG-VEGF), induced proliferation, migration and fenestration (the formation of membrane discontinuities) in capillary endothelial cells derived from endocrine glands. However, EG-VEGF had little or no effect on a variety of other endothelial and non-endothelial cell types tested. Similar to VEGF, EG-VEGF possesses a HIF-1 binding site, and its expression is induced by hypoxia. Both EG-VEGF and VEGF resulted in extensive angiogenesis and cyst formation when delivered in the ovary. However, unlike VEGF, EG-VEGF failed to promote angiogenesis in the cornea or skeletal muscle. Expression of human EG-VEGF messenger RNA is restricted to the steroidogenic glands, ovary, testis, adrenal and placenta and is often complementary to the expression of VEGF, suggesting that these molecules function in a coordinated manner. EG-VEGF is an example of a class of highly specific mitogens that act to regulate proliferation and differentiation of the vascular endothelium in a tissue-specific manner.


Assuntos
Glândulas Endócrinas/fisiologia , Endotélio Vascular/fisiologia , Hormônios Gastrointestinais , Mitógenos/isolamento & purificação , Neovascularização Fisiológica , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Hipóxia Celular , Células Cultivadas , DNA Complementar , Modelos Animais de Doenças , Fatores de Crescimento Endotelial/fisiologia , Feminino , Regulação da Expressão Gênica , Humanos , Linfocinas/fisiologia , Camundongos , Camundongos Nus , Mitógenos/genética , Mitógenos/fisiologia , Dados de Sequência Molecular , Cistos Ovarianos/etiologia , Ratos , Proteínas Recombinantes de Fusão , Homologia de Sequência de Aminoácidos , Distribuição Tecidual , Fator A de Crescimento do Endotélio Vascular , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina , Fatores de Crescimento do Endotélio Vascular
15.
J Natl Cancer Inst ; 93(10): 762-8, 2001 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-11353786

RESUMO

BACKGROUND: Lysophosphatidic acid (LPA) stimulates ovarian tumor growth at concentrations present in ascitic fluid. Vascular endothelial growth factor (VEGF) stimulates angiogenesis and plays a pivotal role in the formation of ovarian cancer-associated ascites. We examined whether LPA promotes ovarian tumor growth by increasing angiogenesis via VEGF. METHODS: VEGF expression was examined in a simian virus 40 T-antigen-immortalized ovarian surface epithelial cell line (IOSE-29) and in ovarian cancer cell lines (OVCAR-3, SKOV-3, and CAOV-3) treated with LPA. VEGF promoter activity was measured in OVCAR-3 cells after transfection or cotransfection with c-Fos and c-Jun, components of AP1 transcription factor, potential binding sites for which are present in the VEGF promoter. The expression of the LPA receptors Edg2 and Edg4 was also assessed. All statistical tests were two-sided. RESULTS: LPA treatment increased steady-state VEGF messenger RNA (mRNA) levels in OVCAR-3 cells in a time- and dose-dependent fashion and stimulated VEGF promoter activity without prolonging mRNA half-life in these cells, but LPA had little effect on IOSE-29 cells. Forced overexpression of c-Jun and c-Fos in OVCAR-3 cells stimulated VEGF promoter activity fourfold. LPA also elevated VEGF protein levels by 1.5-fold in SKOV-3 cells (P =.0148), 1.9-fold in CAOV-3 cells (P<.001), and threefold in OVCAR-3 cells (P<.0001). Both Edg2 and Edg4 were detected in ovarian cancer cells; however, only Edg2 was present in normal ovarian surface epithelial cells and IOSE-29 cells. CONCLUSIONS: LPA stimulates ovarian tumor growth, at least in part, via induction of VEGF expression through transcriptional activation. However, this LPA response is not evident in normal ovarian surface epithelial cells. Our data suggest that Edg4, but not Edg2, plays a role in LPA stimulation of ovarian tumor growth.


Assuntos
Fatores de Crescimento Endotelial/biossíntese , Linfocinas/biossíntese , Lisofosfolipídeos/farmacologia , Neoplasias Ovarianas/metabolismo , Receptores Acoplados a Proteínas G , Antibióticos Antineoplásicos/farmacologia , Sítios de Ligação , Northern Blotting , Linhagem Celular , Linhagem Celular Transformada , Meios de Cultivo Condicionados/metabolismo , Dactinomicina/farmacologia , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Deleção de Genes , Humanos , Luciferases/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/biossíntese , Receptores de Ácidos Lisofosfatídicos , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Tempo , Fator de Transcrição AP-1/metabolismo , Transfecção , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
16.
Proc Natl Acad Sci U S A ; 98(10): 5780-5, 2001 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-11331753

RESUMO

The role of the cardiac myocyte as a mediator of paracrine signaling in the heart has remained unclear. To address this issue, we generated mice with cardiac myocyte-specific deletion of the vascular endothelial growth factor gene, thereby producing a cardiomyocyte-specific knockout of a secreted factor. The hearts of these mice had fewer coronary microvessels, thinned ventricular walls, depressed basal contractile function, induction of hypoxia-responsive genes involved in energy metabolism, and an abnormal response to beta-adrenergic stimulation. These findings establish the critical importance of cardiac myocyte-derived vascular endothelial growth factor in cardiac morphogenesis and determination of heart function. Further, they establish an adult murine model of hypovascular nonnecrotic cardiac contractile dysfunction.


Assuntos
Fatores de Crescimento Endotelial/metabolismo , Coração/fisiologia , Linfocinas/metabolismo , Miocárdio/metabolismo , Animais , Fatores de Crescimento Endotelial/genética , Perfilação da Expressão Gênica , Imuno-Histoquímica , Hibridização In Situ , Linfocinas/genética , Camundongos , Camundongos Knockout , Modelos Animais , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
17.
Am J Physiol Cell Physiol ; 280(6): C1358-66, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11350730

RESUMO

Evidence accumulating over the last decade has established the fundamental role of vascular endothelial growth factor (VEGF) as a key regulator of normal and abnormal angiogenesis. The biological effects of VEGF are mediated by two tyrosine kinase receptors, Flt-1 (VEGFR-1) and KDR (VEGFR-2). The signaling and biological properties of these two receptors are strikingly different. VEGF is essential for early development of the vasculature to the extent that inactivation of even a single allele of the VEGF gene results in embryonic lethality. VEGF is also required for female reproductive functions and endochondral bone formation. Substantial evidence also implicates VEGF as an angiogenic mediator in tumors and intraocular neovascular syndromes, and numerous clinical trials are presently testing the hypothesis that inhibition of VEGF may have therapeutic value.


Assuntos
Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/metabolismo , Linfocinas/genética , Linfocinas/metabolismo , Neovascularização Fisiológica/fisiologia , Animais , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Humanos , Neovascularização Patológica/fisiopatologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
18.
Am J Pathol ; 158(3): 1111-20, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238059

RESUMO

Vascular endothelial growth factor (VEGF) is an important mediator of angiogenesis in both physiological and pathological processes. Hepatocyte growth factor (HGF) is a mesenchyme-derived mitogen that also stimulates cell migration, and branching and/or tubular morphogenesis of epithelial and endothelial cells. In the present study, we tested the hypothesis that simultaneous administration of HGF and VEGF would synergistically promote new blood vessel formation. HGF acted in concert with VEGF to promote human endothelial cell survival and tubulogenesis in 3-D type I collagen gels, a response that did not occur with either growth factor alone. The synergistic effects of VEGF and HGF on endothelial survival correlated with greatly augmented mRNA levels for the anti-apoptotic genes Bcl-2 and A1. Co-culture experiments with human neonatal dermal fibroblasts and human umbilical vein endothelial cells demonstrated that neonatal dermal fibroblasts, in combination with VEGF, stimulated human umbilical vein endothelial cells tubulogenesis through the paracrine secretion of HGF. Finally, in vivo experiments demonstrated that the combination of HGF and VEGF increased neovascularization in the rat corneal assay greater than either growth factor alone. We suggest that combination therapy using HGF and VEGF co-administration may provide a more effective strategy to achieve therapeutic angiogenesis.


Assuntos
Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/efeitos dos fármacos , Fator de Crescimento de Hepatócito/farmacologia , Linfocinas/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Animais , Técnicas de Cultura de Células/métodos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colágeno/fisiologia , Córnea/irrigação sanguínea , Córnea/efeitos dos fármacos , Sinergismo Farmacológico , Endotélio Vascular/citologia , Fibroblastos/fisiologia , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
19.
J Biol Chem ; 276(5): 3222-30, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11058584

RESUMO

Endothelial cells express two related vascular endothelial growth factor (VEGF) receptor tyrosine kinases, KDR (kinase-insert domain containing receptor, or VEGFR-2) and Flt-1 (fms-like tyrosine kinase, or VEGFR-1). Although considerable experimental evidence links KDR activation to endothelial cell mitogenesis, there is still significant uncertainty concerning the role of individual VEGF receptors for other biological effects such as vascular permeability. VEGF mutants that bind to either KDR or Flt-1 with high selectivity were used to determine which of the two receptors serves to mediate different VEGF functions. In addition to mediating mitogenic signaling, selective KDR activation was sufficient for the activation of intracellular signaling pathways implicated in cell migration. KDR stimulation caused tyrosine phosphorylation of both phosphatidylinositol 3-kinase and phospholipase Cgamma in primary endothelial cells and stimulated cell migration. KDR-selective VEGF was also able to induce angiogenesis in the rat cornea to an extent indistinguishable from wild type VEGF. We also demonstrate that KDR, but not Flt-1, stimulation is responsible for the induction of vascular permeability by VEGF.


Assuntos
Endotélio Vascular/citologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Transdução de Sinais/fisiologia , Permeabilidade Capilar/fisiologia , Movimento Celular/fisiologia , Células Cultivadas , Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/fisiologia , Ativação Enzimática , Humanos , Isoenzimas/metabolismo , Linfocinas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Neovascularização Fisiológica/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipase C gama , Receptores de Fatores de Crescimento do Endotélio Vascular , Fosfolipases Tipo C/metabolismo , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
20.
Acta Haematol ; 106(4): 148-56, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11815711

RESUMO

Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen and an angiogenic inducer as well as a mediator of vascular permeability. The biological effects of VEGF are mediated by two tyrosine kinase receptors, Flt-1 (VEGFr-1) and KDR (VEGFR-2). VEGF is essential for developmental angiogenesis and is also required for female reproductive functions and endochondral bone formation. Substantial evidence also implicates VEGF in tumors and intraocular neovascular syndromes. Currently, several clinical trials are ongoing to test the hypothesis that inhibition of VEGF activity may be beneficial for these conditions.


Assuntos
Fatores de Crescimento Endotelial/fisiologia , Linfocinas/fisiologia , Neovascularização Fisiológica/fisiologia , Animais , Anticorpos Monoclonais/uso terapêutico , Fatores de Crescimento Endotelial/imunologia , Fatores de Crescimento Endotelial/metabolismo , Feminino , Humanos , Linfocinas/imunologia , Linfocinas/metabolismo , Masculino , Neovascularização Patológica/fisiopatologia , Gravidez , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Receptores de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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