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1.
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
2.
Nutr Metab Cardiovasc Dis ; 28(3): 206-218, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29337017

RESUMO

Type 2 diabetes prevalence is high in older adults and is expected to rise in the next decades. Diabetes in the population of frail older adults is accompanied by functional disability, several comorbidities, and premature mortality. A comprehensive geriatric assessment, including functional, cognitive, mental and social status, is advisable for identifying the glycemic targets and glucose-lowering therapies, focused on patient preferences, needs, and risks. The therapeutic options for older adults with diabetes are like those for the adult population. However, the pharmacological treatments must be carefully prescribed and monitored, taking into consideration the patient cognitive capacities, the potentially life-threatening drug-drug interactions, the cardiovascular risk, and with the main goal of avoiding hypoglycemia. Also, a careful nutritional evaluation with appropriate tools, as well as a balanced and periodically monitored physical activity, contribute to an effective tailored care plan, as needed by older adults with diabetes. This review evaluates the currently available hypoglycemic drugs and the current indications to the Italian diabetology community, specifically with regard to the treatment of adults aged 75 years or older with diabetes, including the unmet needs by the guidelines.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Assistência Centrada no Paciente , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Biomarcadores/sangue , Glicemia/metabolismo , Tomada de Decisão Clínica , Cognição , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/psicologia , Interações Medicamentosas , Feminino , Avaliação Geriátrica , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Itália , Masculino , Saúde Mental , Estado Nutricional , Fatores de Risco , Resultado do Tratamento
3.
Nutr Metab Cardiovasc Dis ; 28(2): 126-132, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29198416

RESUMO

BACKGROUND AND AIMS: Sleep-disordered breathing (SDB) is common in patients with heart failure (HF), contributes to the progression of cardiac disease, and is associated with adverse prognosis. Previous evidence indicates that epicardial adipose tissue (EAT) is independently associated with sleep apnea in obese individuals. We explored the relationship between SDB and EAT in HF patients. METHODS AND RESULTS: EAT thickness was assessed by echocardiography in 66 patients with systolic HF undergoing nocturnal cardiorespiratory monitoring. A significantly higher EAT thickness was found in patients with SDB than in those without SDB (10.7 ± 2.8 mm vs. 8.3 ± 1.8 mm; p = 0.001). Among SDB patients, higher EAT thickness was found in both those with prevalent obstructive sleep apnea (OSA) and those with prevalent central sleep apnea (CSA). Of interest, EAT thickness was significantly higher in CSA than in OSA patients (11.9 ± 2.9 vs. 10.1 ± 2.5 p = 0.022). Circulating plasma norepinephrine levels were higher in CSA than in OSA patients (2.19 ± 1.25 vs. 1.22 ± 0.92 ng/ml, p = 0.019). According to the apnea-hypopnea index (AHI), patients were then stratified in three groups of SDB severity: Group 1, mild SDB; Group 2, moderate SDB; Group 3, severe SDB. EAT thickness progressively and significantly increased from Group 1 to Group 3 (ANOVA p < 0.001). At univariate analysis, only left ventricular ejection fraction and AHI significantly correlated with EAT (p = 0.019 and p < 0.0001, respectively). At multivariate analysis, AHI was the only independent predictor of EAT (ß = 0.552, p < 0.001). CONCLUSIONS: Our results suggest an association between the presence and severity of sleep apneas and cardiac visceral adiposity in HF patients.


Assuntos
Adiposidade , Insuficiência Cardíaca/fisiopatologia , Gordura Intra-Abdominal/fisiopatologia , Pericárdio/fisiopatologia , Apneia do Sono Tipo Central/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Idoso , Ecocardiografia , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Pericárdio/diagnóstico por imagem , Polissonografia , Prevalência , Prognóstico , Índice de Gravidade de Doença , Apneia do Sono Tipo Central/diagnóstico , Apneia do Sono Tipo Central/epidemiologia , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia
4.
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
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.
Nat Med ; 5(12): 1359-64, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10581076
7.
Nat Med ; 5(6): 623-8, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10371499

RESUMO

Hypertrophic chondrocytes in the epiphyseal growth plate express the angiogenic protein vascular endothelial growth factor (VEGF). To determine the role of VEGF in endochondral bone formation, we inactivated this factor through the systemic administration of a soluble receptor chimeric protein (Flt-(1-3)-IgG) to 24-day-old mice. Blood vessel invasion was almost completely suppressed, concomitant with impaired trabecular bone formation and expansion of hypertrophic chondrocyte zone. Recruitment and/or differentiation of chondroclasts, which express gelatinase B/matrix metalloproteinase-9, and resorption of terminal chondrocytes decreased. Although proliferation, differentiation and maturation of chondrocytes were apparently normal, resorption was inhibited. Cessation of the anti-VEGF treatment was followed by capillary invasion, restoration of bone growth, resorption of the hypertrophic cartilage and normalization of the growth plate architecture. These findings indicate that VEGF-mediated capillary invasion is an essential signal that regulates growth plate morphogenesis and triggers cartilage remodeling. Thus, VEGF is an essential coordinator of chondrocyte death, chondroclast function, extracellular matrix remodeling, angiogenesis and bone formation in the growth plate.


Assuntos
Osso e Ossos/fisiologia , Cartilagem/fisiologia , Condrócitos/metabolismo , Fatores de Crescimento Endotelial/fisiologia , Linfocinas/fisiologia , Neovascularização Fisiológica/fisiologia , Osteogênese/fisiologia , Animais , Osso e Ossos/anatomia & histologia , Cartilagem/anatomia & histologia , Divisão Celular , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Imunoglobulina G/genética , Imunoglobulina G/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/farmacologia , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Receptores Proteína Tirosina Quinases/farmacologia , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/farmacologia , Fatores de Crescimento do Endotélio Vascular
8.
Nat Med ; 4(3): 336-40, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9500609

RESUMO

The development and endocrine function of the ovarian corpus luteum (CL) are dependent on the growth of new capillary vessels. Although several molecules have been implicated as mediators of CL angiogenesis, at present there is no direct evidence for the involvement of any. Here we report the unexpected finding that treatment with truncated soluble Flt-1 receptors, which inhibit vascular endothelial growth factor (VEGF) bioactivity, resulted in virtually complete suppression of CL angiogenesis in a rat model of hormonally induced ovulation. This effect was associated with inhibition of CL development and progesterone release. Failure of maturation of the endometrium was also observed. Areas of ischemic necrosis were demonstrated in the corpora lutea (CLs) of treated animals. However, no effect on the preexisting ovarian vasculature was observed. These findings demonstrate that, in spite of the redundancy of potential mediators, VEGF is essential for CL angiogenesis. Furthermore, they have implications for the control of fertility and the treatment of ovarian disorders characterized by hypervascularity and hyperplasia.


Assuntos
Corpo Lúteo/irrigação sanguínea , Fatores de Crescimento Endotelial/farmacologia , Linfocinas/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Animais , Corpo Lúteo/anatomia & histologia , Fatores de Crescimento Endotelial/antagonistas & inibidores , Fatores de Crescimento Endotelial/genética , Feminino , Gonadotropinas/farmacologia , Hibridização in Situ Fluorescente , Linfocinas/antagonistas & inibidores , Linfocinas/genética , Ratos , Ratos Sprague-Dawley , Útero/anatomia & histologia , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
9.
Clin Exp Rheumatol ; 28(2): 215-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20483043

RESUMO

OBJECTIVES: The purpose of the present study was to produce an Italian version of the Canadian Occupational Performance Measure (COPM) in a group of patients with Ankylosing Spondylitis (AS) and examine the psychometric properties of this version, evaluating its internal consistency, external validity and reliability. Responsiveness and feasibility were also taken into account. METHODS: The Italian COPM, the Italian version of the COPM, was administered to 30 Caucasian patients affected by AS (24 males, 6 females, median age 48 yrs, range 32-67, median disease duration 14 yrs, range 1-30 yrs) together with the Bath Ankylosing Spondylitis Functional Index (BASFI), the Bath Ankylosing Spondylitis Disease Activity (BASDAI) and the Italian version of the Health Assessment Questionnaire (HAQ). Internal consistency was evaluated with Cronbach's alpha for reliability. Construct validity of the COPM was evaluated by a correlation between the BASFI, BASDAI and HAQ scores. Test-retest reliability was assessed by the Intraclass correlation coefficient. Responsiveness and feasibility were also considered. RESULTS: All patients completed the validation study. The questionnaire was internally consistent (alpha coefficient=0.774). A significant correlation was recorded between the COPM and the BASFI (rho=-0.566, p<0.01), BASDAI (rho=-0.491, p<0.01). Test-retest reliability showed a good correlation coefficient and it was confirmed by Bland-Altman method. CONCLUSIONS: The Italian COPM is a valid and reliable instrument focused to detect change in a client's perception of occupational performance over time, in AS patients. Our results confirm the utility of this questionnaire to measure outcome and in planning treatment intervention for patients with AS.


Assuntos
Avaliação da Deficiência , Psicometria/normas , Espondilite Anquilosante/fisiopatologia , Inquéritos e Questionários/normas , Adulto , Idoso , Canadá , Estudos de Viabilidade , Feminino , Humanos , Itália , Idioma , Masculino , Pessoa de Meia-Idade , Ocupações , Reprodutibilidade dos Testes
10.
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
11.
Science ; 246(4935): 1306-9, 1989 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-2479986

RESUMO

Vascular endothelial growth factor (VEGF) was purified from media conditioned by bovine pituitary folliculostellate cells (FC). VEGF is a heparin-binding growth factor specific for vascular endothelial cells that is able to induce angiogenesis in vivo. Complementary DNA clones for bovine and human VEGF were isolated from cDNA libraries prepared from FC and HL60 leukemia cells, respectively. These cDNAs encode hydrophilic proteins with sequences related to those of the A and B chains of platelet-derived growth factor. DNA sequencing suggests the existence of several molecular species of VEGF. VEGFs are secreted proteins, in contrast to other endothelial cell mitogens such as acidic or basic fibroblast growth factors and platelet-derived endothelial cell growth factor. Human 293 cells transfected with an expression vector containing a bovine or human VEGF cDNA insert secrete an endothelial cell mitogen that behaves like native VEGF.


Assuntos
Endotélio Vascular/citologia , Linfocinas/fisiologia , Neovascularização Patológica/fisiopatologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Bovinos , Divisão Celular , Clonagem Molecular , Biblioteca Gênica , Humanos , Linfocinas/genética , Linfocinas/metabolismo , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
12.
Science ; 255(5047): 989-91, 1992 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-1312256

RESUMO

The fms-like tyrosine kinase (Flt) is a transmembrane receptor in the tyrosine kinase family. Expression of flt complementary DNA in COS cells conferred specific, high-affinity binding of vascular endothelial growth factor, also known as vascular permeability factor (VEGF-VPF), a factor that induces vascular permeability when injected in the guinea pig skin and stimulates endothelial cell proliferation. Expression of Flt in Xenopus laevis oocytes caused the oocytes to release calcium in response to VEGF-VPF. These findings show that flt encodes a receptor for VEGF-VPF.


Assuntos
Fatores de Crescimento Endotelial/fisiologia , Linfocinas/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores de Superfície Celular/genética , Animais , Clonagem Molecular , Reagentes de Ligações Cruzadas , Ativação Enzimática , Humanos , Técnicas In Vitro , Proteínas Proto-Oncogênicas/genética , Transdução de Sinais , Transfecção , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Xenopus laevis
13.
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
14.
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
15.
Oxid Med Cell Longev ; 2018: 2731289, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30116475

RESUMO

BACKGROUND: Several dietary phytochemicals potentially regulate the equilibrium between oxidant and antioxidant species. The aim of this study was to evaluate the effects of Lippia citriodora, Raphanus sativus, and Solanum lycopersicum on blood parameters, oxidative/antioxidant status, and SIRT1 activity in the rabbit's heart and liver. METHODS: Twenty rabbits were divided into 4 groups of 5 animals each. The control group (CN) received a feed without any additives. One intervention group received a supplement containing verbascoside (VB), another Raphanus sativus extract (RAP), and lastly lycopene (LYC). Oxidant-antioxidant parameters and SIRT1 activity were measured in plasma and in the heart and liver, respectively. RESULTS: The treatment with VB, RAP, and LYC resulted in a marked improvement in the blood lipid and glycaemic profile in respect to CN. VB was the most effective, but all three plant extracts induced a significant reduction in oxidant parameters as well as an increase in antioxidant tissue activity and vitamin A and E levels. SIRT1 activity was significantly increased in both VB and LYC compared to CN, but the increased levels in the VB group were far the highest. The multivariate analysis suggests that the benefits of VB, particularly the antiglycaemic and antioxidant effects, might be mediated by increasing SIRT1 activity.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/uso terapêutico , Coração/efeitos dos fármacos , Fígado/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Antioxidantes/farmacologia , Masculino , Extratos Vegetais/farmacologia , Coelhos , Sirtuína 1/metabolismo
16.
J Clin Invest ; 95(4): 1789-97, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7535799

RESUMO

To investigate the relationship between angiogenesis and hepatic tumorigenesis, we examined the expression of vascular endothelial growth factor (VEGF) in 8 human colon carcinoma cell lines and in 30 human colorectal cancer liver metastases. Abundant message for VEGF was found in all tumors, localized to the malignant cells within each neoplasm. Two receptors for VEGF, KDR and flt1, were also demonstrated in most of the tumors examined. KDR and flt1 mRNA were limited to tumor endothelial cells and were more strongly expressed in the hepatic metastases than in the sinusoidal endothelium of the surrounding liver parenchyma. VEGF monoclonal antibody administration in tumor-bearing athymic mice led to a dose- and time-dependent inhibition of growth of subcutaneous xenografts and to a marked reduction in the number and size of experimental liver metastases. In hepatic metastases of VEGF antibody-treated mice, neither blood vessels nor expression of the mouse KDR homologue flk-1 could be demonstrated. These data indicate that VEGF is a commonly expressed angiogenic factor in human colorectal cancer metastases, that VEGF receptors are up-regulated as a concomitant of hepatic tumorigenesis, and that modulation of VEGF gene expression or activity may represent a potentially effective antineoplastic therapy in colorectal cancer.


Assuntos
Carcinoma/patologia , Neoplasias do Colo/patologia , Fatores de Crescimento Endotelial/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Hepáticas/secundário , Linfocinas/metabolismo , Animais , Elementos Antissenso (Genética) , Movimento Celular , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/imunologia , Feminino , Humanos , Hibridização In Situ , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/genética , Linfocinas/genética , Linfocinas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Transplante Heterólogo , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
17.
J Clin Invest ; 89(1): 244-53, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1729274

RESUMO

Vascular endothelial growth factor (VEGF) is a secreted heparin-binding mitogen; its growth-promoting activity is limited to vascular endothelial cells in vitro and VEGF also stimulates angiogenesis in vivo. To identify target cells for VEGF and investigate the potential physiological role of this factor, iodinated recombinant human VEGF (125I-rhVEGF) was used for in vitro ligand autoradiography on tissue sections from adult rats. 125I-rhVEGF exhibited saturable, displaceable binding to a single class of sites with high affinity and low capacity in all tissues and organs examined. Colocalization of 125I-rhVEGF binding with Factor VIII-like immunoreactivity demonstrated binding sites associated with vascular endothelial cells of both fenestrated and nonfenestrated microvessels and the endothelium of large vessels, while no displaceable binding was evident on nonendothelial cells. Specific binding was associated with quiescent as well as proliferating vessels. These findings support the hypothesis that VEGF plays a specific role in both the maintenance and in the induction of growth of vascular endothelial cells.


Assuntos
Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/metabolismo , Linfocinas/metabolismo , Receptores Mitogênicos/metabolismo , Animais , Autorradiografia , Ligação Competitiva , Química Encefálica , Endotélio Vascular/citologia , Fator VII/isolamento & purificação , Fator VII/metabolismo , Feminino , Rim/química , Cinética , Fígado/química , Masculino , Microtomia , Miocárdio/química , Especificidade de Órgãos , Ovário/química , Ratos , Receptores Mitogênicos/isolamento & purificação , Receptores de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
18.
J Clin Invest ; 91(1): 160-70, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8423215

RESUMO

Vascular endothelial growth factor (VEGF) is a mitogen with a specificity for endothelial cells in vitro and an angiogenic inducer in vivo. We tested the hypothesis that VEGF may confer on expressing cells a growth advantage in vivo. Dihydrofolatereductase--Chinese hamster ovary cells were transfected with expression vectors which direct the constitutive synthesis of VEGF. Neither the expression nor the exogenous administration of VEGF stimulated anchorage-dependent or anchorage-independent growth of Chinese hamster ovary cells in vitro. However, VEGF-expressing clones, unlike control cells, demonstrated an ability to proliferate in nude mice. Histologic examination revealed that the proliferative lesions were compact, well vascularized, and nonedematous. Ultrastructural analysis revealed that capillaries within the lesions were of the continuous type. These findings indicate that the expression of VEGF may confer on cells the ability to grow in vivo in the absence of transformation by purely paracrine mechanisms. Since VEGF is a widely distributed protein, this property may have relevance for a variety of physiological and pathological proliferative processes.


Assuntos
Divisão Celular/fisiologia , Transformação Celular Neoplásica , Fatores de Crescimento Endotelial/biossíntese , Fatores de Crescimento Endotelial/farmacologia , Linfocinas/biossíntese , Linfocinas/farmacologia , Transfecção , Animais , Células CHO , Divisão Celular/efeitos dos fármacos , Células Clonais , Cricetinae , Fatores de Crescimento Endotelial/genética , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos , Humanos , Hibridização In Situ , Cinética , Linfocinas/genética , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/ultraestrutura , RNA Mensageiro/análise , Proteínas Recombinantes/análise , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
19.
J Clin Invest ; 93(2): 662-70, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7509344

RESUMO

Vascular endothelial growth factor (VEGF) is a heparin-binding, endothelial cell-specific mitogen. Previous studies have suggested that VEGF is a regulator of naturally occurring physiologic and pathologic angiogenesis. In this study we investigated the hypothesis that the angiogenic potential of VEGF is sufficient to constitute a therapeutic effect. The soluble 165-amino acid isoform of VEGF was administered as a single intra-arterial bolus to the internal iliac artery of rabbits in which the ipsilateral femoral artery was excised to induce severe, unilateral hind limb ischemia. Doses of 500-1,000 micrograms of VEGF produced statistically significant augmentation of collateral vessel development by angiography as well as the number of capillaries by histology; consequent amelioration of the hemodynamic deficit in the ischemic limb was significantly greater in animals receiving VEGF than in nontreated controls (calf blood pressure ratio, 0.75 +/- 0.14 vs. 0.48 +/- 0.19, P < 0.05). Serial angiograms disclosed progressive linear extension of the collateral artery of origin (stem artery) to the distal point of parent vessel (reentry artery) reconstitution in seven of nine VEGF-treated animals. These findings establish proof of principle for the concept that the angiogenic activity of VEGF is sufficiently potent to achieve therapeutic benefit. Such a strategy might ultimately be applicable to patients with severe limb ischemia secondary to arterial occlusive disease.


Assuntos
Fatores de Crescimento Endotelial/uso terapêutico , Isquemia/terapia , Linfocinas/uso terapêutico , Músculos/irrigação sanguínea , Neovascularização Patológica , Angiografia , Animais , Células CHO , Capilares/efeitos dos fármacos , Cricetinae , Relação Dose-Resposta a Droga , Fatores de Crescimento Endotelial/administração & dosagem , Fatores de Crescimento Endotelial/biossíntese , Membro Posterior/irrigação sanguínea , Humanos , Injeções Intra-Arteriais , Linfocinas/administração & dosagem , Linfocinas/biossíntese , Masculino , Músculos/patologia , Coelhos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/uso terapêutico , Transfecção , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
20.
J Clin Invest ; 104(11): 1613-20, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10587525

RESUMO

VEGF is mitogenic, angiogenic, and a potent mediator of vascular permeability. VEGF causes extravasation of plasma protein in skin bioassays and increases hydraulic conductivity in isolated perfused microvessels. Reduced tissue oxygen tension triggers VEGF expression, and increased protein and mRNA levels for VEGF and its receptors (Flt-1, Flk-1/KDR) occur in the ischemic rat brain. Brain edema, provoked in part by enhanced cerebrovascular permeability, is a major complication in central nervous system pathologies, including head trauma and stroke. The role of VEGF in this pathology has remained elusive because of the lack of a suitable experimental antagonist. We used a novel fusion protein, mFlt(1-3)-IgG, which sequesters murine VEGF, to treat mice exposed to transient cortical ischemia followed by reperfusion. Using high-resolution magnetic resonance imaging, we found a significant reduction in volume of the edematous tissue 1 day after onset of ischemia in mice that received mFlt(1-3)-IgG. 8-12 weeks after treatment, measurements of the resultant infarct size revealed a significant sparing of cortical tissue. Regional cerebral blood flow was unaffected by the administration of mFlt(1-3)-IgG. These results demonstrate that antagonism of VEGF reduces ischemia/reperfusion-related brain edema and injury, implicating VEGF in the pathogenesis of stroke and related disorders.


Assuntos
Edema Encefálico/patologia , Isquemia Encefálica/fisiopatologia , Encéfalo/irrigação sanguínea , Fatores de Crescimento Endotelial/farmacologia , Linfocinas/farmacologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Encéfalo/patologia , Fatores de Crescimento Endotelial/antagonistas & inibidores , Histocitoquímica , Imunoglobulina G/genética , Injeções Intraperitoneais , Ligadura , Linfocinas/antagonistas & inibidores , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Proteínas Recombinantes de Fusão/farmacologia , Fluxo Sanguíneo Regional , 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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