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1.
J Prev Alzheimers Dis ; 2(1): 33-37, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-29234773

RESUMO

Methionine sulfoxide reductase A (MsrA) has been postulated to act as a catalytic antioxidant system involved in the protection of oxidative stress-induced cell injury. MsrA has recently turned attention in coupling with the neurodegenerative disorders and in particular with Alzheimer disease. In fact this neurodegenerative disorder depends to a deposit of beta amyloid a peptide with an oxidizable methionine in position 35 which is proved able to modulate the expression to MsrA in neuronal cells. Here, we firstly provided evidence that pretreatment with Resveratrol and Punicalagin (a potent antioxidant extracted from pomegranate), up-regulate the expression and enzymatic activity of MsrA in human neuroblastoma IMR-32 cells with beta amyloid peptides. This effect determines a lowering of oxidative potential of the cells as demonstrated by the ROS measurement and a protective effect on cellular availability. Therefore we hypothesize a possible prevent role for these molecules in Alzheimer and in other neurodegenerative diseases.

2.
Curr Med Chem ; 18(8): 1146-63, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21291369

RESUMO

Cardiovascular disease (CVD) is the leading cause of death in Western societies and accounts for up to a third of all deaths worldwide. In comparison to the Northern European or other Western countries, the Mediterranean area has lower rates of mortality from cardiovascular diseases and cancer, and this is attributed, at least in part, to the so-called Mediterranean diet, which is rich in plantderived bioactive phytochemicals. Identification of the active constituents of the Mediterranean diet is therefore crucial to the formulation of appropriate dietary guidelines. Lycopene is a natural carotenoid found in tomato, an essential component of the Mediterranean diet, which, although belonging to the carotenoid family, does not have pro-vitamin A activity but many other biochemical functions as an antioxidant scavenger, hypolipaemic agent, inhibitor of pro-inflammatory and pro-thrombotic factors, thus potentially of benefit in CVD. In particular, the review intends to conduct a systematic analysis of the literature (epidemiological studies and interventional trials) in order to critically evaluate the association between lycopene (or tomato products) supplementation and cardiovascular diseases and/or cardiovascular disease risk factors progression, and to prepare provision of evidence-based guidelines for patients and clinicians. Several reports have appeared in support of the role of lycopene in the prevention of CVD, mostly based on epidemiological studies showing a dose-response relationship between lycopene and CVD. A less clear and more complex picture emerges from the interventional trials, where several works have reported conflicting results. Although many aspects of lycopene in vivo metabolism, functions and clinical indications remain to be clarified, supplementation of low doses of lycopene has been already suggested as a preventive measure for contrasting and ameliorating many aspects of CVD.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Carotenoides/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Carotenoides/química , Carotenoides/metabolismo , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Humanos , Licopeno , Solanum lycopersicum/química , Solanum lycopersicum/metabolismo , Estrutura Molecular
3.
Luminescence ; 26(5): 331-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20812198

RESUMO

Cigarette smoking plays an important role as a cause of morbidity and mortality in humans, involving respiratory, cardiovascular, digestive and reproductive systems. Tobacco smoke contains a large number of molecules, some of which are proven carcinogens. Although not fully understood, polymorphonuclear leukocytes seem to play a crucial role in the mechanisms by which tobacco smoke compounds are implicated in smoke-related diseases. In this paper the effects of an aqueous cigarette smoke extract on the expression of adhesion molecules of polymorphonuclear leukocytes together with the changes in the cell morphology have been related to the chemiluminescence activity. The results obtained show that polymorphonuclear leukocytes treated with aqueous cigarette smoke extract are significantly impaired, as suggested by the changes of chemiluminescence activity, of membrane receptors (CD18, CD62), myeloperoxidase expression and of cell morphology. Altogether the present data indicate that treated polymorphonuclear leukocytes are ineffectively activated and therefore unable to phagocytize zymosan particles.


Assuntos
Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Fumaça/efeitos adversos , Fumar/efeitos adversos , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/imunologia , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Humanos , Medições Luminescentes , Neutrófilos/química , Neutrófilos/imunologia , Fumaça/análise , Fumar/imunologia , /química
4.
Curr Med Chem ; 16(13): 1656-72, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19442138

RESUMO

Anthracyclines are among the most effective anticancer drugs ever developed. Unfortunately, their clinical use is severely limited by the development of a progressive dose-dependent cardiomyopathy that irreversibly evolves toward congestive heart failure, usually refractory to conventional therapy. The pathophysiology of anthracycline-induced cardiomyopathy remains controversial and incompletely understood. The current thinking is that anthracyclines are toxic per se but gain further cardiotoxicity after one-electron reduction with ROS overproduction or two-electron reduction with conversion to C-13 alcohol metabolites. ROS overproduction can probably be held responsible for anthracycline acute cardiotoxicity, but not for all the aspects of progressive cardiomyopathy. Intramyocardial formation of secondary alcohol metabolites might play a key role in promoting the progression of cardiotoxicity toward end-stage cardiomyopathy and congestive heart failure. In this review we also discuss recent developments in: a) the molecular mechanisms underlying anthracycline-induced cardiotoxicity; b) the role of cytosolic NADPH-dependent reductases in anthracycline metabolism; c) the influence of genetic polymorphisms on cardiotoxicity outcome; d) the perspectives on the most promising strategies for limiting or preventing anthracycline-induced cardiotoxicity, focusing on controversial aspects and on recent data regarding analogues of the natural compounds, tumor-targeted formulations and cardioprotective agents.


Assuntos
Antraciclinas/toxicidade , Coração/efeitos dos fármacos , Citosol/metabolismo , Humanos , NADP/metabolismo , Polimorfismo Genético , Espécies Reativas de Oxigênio/metabolismo
5.
Protein J ; 27(1): 13-20, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17786545

RESUMO

Three proteins belonging to the thaumatin-like proteins family were compared in this study from a structural point of view: zeamatin, a new recently isolated PR-5 from Cassia didymobotrya and the commercial sweet-thaumatin. The former two proteins possess antifungal activities while commercial thaumatin is well known to be a natural sweetener. Intrinsic fluorescence studies have evidenced that the three proteins behave differently in unfolding experiments showing different structural rigidity. All the three proteins are more stable at slight acidic buffers, but sweet-thaumatin has a major tendency to destructurate itself. Similar observations were made from circular dichroism studies where a structural dependence relationship from the pH and the solvent used confirmed a hierarchic scale of stability for the three proteins. These structural differences should be considered to be significant for a functional role.


Assuntos
Antifúngicos/química , Cassia/química , Proteínas de Plantas/química , Dicroísmo Circular , Dobramento de Proteína , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Physiol Res ; 57(4): 621-629, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17705675

RESUMO

The effects of gemfibrozil (GFZ), an antihyperlipidemic agent, on the anionic transport of the human red blood cells (RBC) during the oxygenation-deoxygenation cycle were examined. Gemfibrozil clearly plays a role in the modulation of the anionic flux in erythrocytes; in fact it causes a strong increment of anions transport when the RBCs are in the high-oxygenation state (HOS). Such an effect is remarkably reduced in the low-oxygenation state (LOS). With the aim of identifying the dynamics of fibrate action, this effect has been investigated also in human ghost and chicken erythrocytes. These latter, in fact, are known to possess a B3 (anion transporter or Band 3) modified at the cytoplasmic domain (cdb3) which plays a significant role in the metabolic modulation of red blood cells. The results were analyzed taking into account the well-known interactions between fibrates and both conformational states of hemoglobin i.e. the T state (deoxy-conformation) and the R state (oxy-conformation). The effect of gemfibrozil on anionic influx appears to be due to a wide interaction involving a "multimeric" Hb-GFZ-cdb3 macromolecular complex.


Assuntos
Eritrócitos/metabolismo , Genfibrozila/farmacologia , Hipolipemiantes/farmacologia , Consumo de Oxigênio/fisiologia , Sulfatos/sangue , Adulto , Soluções Tampão , Calibragem , Relação Dose-Resposta a Droga , Membrana Eritrocítica , Eritrócitos/efeitos dos fármacos , Hemoglobinas/metabolismo , Humanos , Técnicas In Vitro , Indicadores e Reagentes , Cinética , Pessoa de Meia-Idade , Consumo de Oxigênio/efeitos dos fármacos , Fosfoproteínas Fosfatases/metabolismo , Conformação Proteica , Vanadatos/farmacologia
7.
Physiol Res ; 57(1): 49-54, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17298204

RESUMO

During vertebrate evolution, structural changes in red blood cells (RBC) and hemoglobin (Hb), have probably resulted in the importance of blood carbon dioxide transport. The chloride/bicarbonate exchange across the RBC membrane, which is an integral part of the blood CO(2) transport process in vertebrates, has been examined on two different species of teleost fish, Euthynnus alletteratus and Thunnus thynnus, at several oxygenation states of erythrocyte HOS (high-oxygenation state, about 90 % of saturation) and LOS (low-oxygenation state, about 15 % of saturation). The results were compared with those observed in human RBC under the same experimental conditions and with the chicken (Gallus gallus) erythrocytes, which have particular modifications at the N-terminus of the band 3 protein (B3). In fish the kinetic measurements have shown a different anion transport in several oxygenation states of erythrocytes, indicating that also at lower levels of vertebrate evolution there exists a modulation of the anionic flow affected by oxygen. The functional correlation of anion transport to changes of parts of the hemoglobin sequence responsible for alterations in the interactions with the cytoplasmic domain of band 3 protein (cdb3) allowed us to suggest a hypothesis about fish physiology. The highest values of kinetic measurements observed in fish have been attributed to the metabolic need of the RBC in response to the removal of CO(2) that in teleosts is also of endogenous origin.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/fisiologia , Dióxido de Carbono/sangue , Eritrócitos/metabolismo , Proteínas de Peixes/fisiologia , Transporte de Íons/fisiologia , Atum/metabolismo , Adulto , Animais , Galinhas , Hemoglobinas/química , Hemoglobinas/metabolismo , Humanos , Pessoa de Meia-Idade , Oxigênio/sangue , Especificidade da Espécie
8.
Clin Biochem ; 40(9-10): 661-5, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17328883

RESUMO

OBJECTIVES: Recent studies describe the potential use of biochemical markers in the evaluation of the severity of periodontitis; moreover, patients suffering from periodontitis frequently complain of halitosis (breath malodour), mainly depending on volatile compounds (e.g. hydrogen sulphide, methyl mercaptan, etc.) produced by anaerobic metabolism of oral bacteria and involving sulphur-containing amino acids. In this study, salivary sulphur compounds, such as cysteine, cysteinylglycine and glutathione and some markers of cellular damage (lactate dehydrogenase and aspartate amino transferase), were measured in periodontitis patients and correlated with the periodontal probing pocket's depth. DESIGN AND METHODS: Twenty-two periodontitis patients and forty control subjects were studied for the salivary activities of lactate dehydrogenase and aspartate aminotransferase and cysteine, cysteinylglycine and glutathione concentrations. The periodontitis patients were divided into two subgroups based on the severity of periodontal disease, expressed as median periodontal probing pocket depth (> or <5 mm). Enzyme activities were measured by using an automated clinical analyzer; cysteine, cysteinylglycine and glutathione concentrations were measured by HPLC equipped with fluorescence detector. RESULTS: A statistically significant increase of the salivary parameters level (cysteine, cysteinylglycine, glutathione, aspartate aminotransferase and lactate dehydrogenase) was found in the patient subgroup with periodontal probing pocket depth >5 mm, the salivary cysteine concentrations showing the most significant correlation. CONCLUSIONS: Salivary cysteine, a direct precursor of hydrogen sulphide, could be considered reliable markers for the oral tissue damage severity in periodontitis patients.


Assuntos
Biomarcadores/análise , Periodontite/diagnóstico , Saliva/química , Compostos de Sulfidrila/análise , Adulto , Idoso , Aspartato Aminotransferases/análise , Cisteína/análise , Dipeptídeos/análise , Feminino , Glutationa/análise , Humanos , L-Lactato Desidrogenase/análise , Masculino , Pessoa de Meia-Idade , Bolsa Periodontal/patologia , Saliva/enzimologia
9.
J Dent ; 35(3): 187-94, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16979810

RESUMO

OBJECTIVES: Methacrylic compounds such as 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA) and bisphenol A glycerolate (1 glycerol/phenol) dimethacrylate (Bis-GMA) are largely present in auto- or photopolymerizable composite resins. Since the polymerization reaction is never complete, these molecules are released into the oral cavity tissues and biological fluids where they could cause local adverse effects. The aim of this work was to verify the hypothesis that the biological effects of HEMA, TEGDMA and Bis-GMA - at a non-cytotoxic concentration - depend on the interaction with mitochondria and exert consequent alterations of energy metabolism, GSH levels and the related pathways in human promyelocytic cell line (HL-60). METHODS: The biological effects of methacrylic monomers were determined by analyzing the following parameters: GSH concentration, glucose-6-phosphate dehydrogenase (G6PDH) and glutathione reductase (GR) activity, oxygen and glucose consumption and lactate production along with cell differentiation and proliferation. RESULTS: All monomers induced both cellular differentiation and decrease in oxygen consumption. Cells treated with TEGDMA and Bis-GMA showed a significant enhancement of glucose consumption and lactate production. TEGDMA and HEMA induced GSH depletion stimulating G6PDH and GR activity. CONCLUSIONS: All the monomers under study affect the metabolism of HL-60 cells and show differentiating activity. Since alterations in cellular metabolism occurred at compound concentrations well below cytotoxic levels, the changes in energy metabolism and glutathione redox balance could be considered as potential mechanisms for inducing clinical and sub-clinical adverse effects and thus providing useful parameters when testing biocompatibility of dental materials.


Assuntos
Resinas Compostas/farmacologia , Materiais Dentários/farmacologia , Metabolismo Energético/efeitos dos fármacos , Glutationa/metabolismo , Metacrilatos/farmacologia , Bis-Fenol A-Glicidil Metacrilato/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glucose/metabolismo , Glucosefosfato Desidrogenase/efeitos dos fármacos , Glutationa Redutase/efeitos dos fármacos , Células HL-60 , Humanos , Ácido Láctico/metabolismo , Mitocôndrias/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Polímeros , Ácidos Polimetacrílicos/farmacologia
10.
Brain Res Bull ; 71(1-3): 29-36, 2006 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-17113925

RESUMO

Amyloid beta (1-42) peptide is considered responsible for the formation of senile plaques that accumulate in the brains of patients with Alzheimer's disease (AD). In the last years considerable attention has been focused on identifying natural food products, such as phytochemicals that prevent or almost retard the appearance of amyloid beta (1-42)-related neurotoxic effects. In this study, human neuroblastoma cells (IMR-32) was used as system model to evaluate the protective role of rhaponticin (3,3',5-trihydroxy-4'-methoxystilbene 3-O-d-glucoside) a stilbene glucoside extracted from rhubarb roots (Rhei rhizoma) and rhapontigenin, its aglycone metabolite, against amyloid beta (1-42)-dependent toxicity. The obtained results show that rhapontigenin maintains significant cell viability in a dose-dependent manner and it exerts a protective effect on mitochondrial functionality, as evidenced by mitochondrial oxygen consumption experiments. A similar behaviour, but to a lesser extent, has been shown by rhaponticin. The protective mechanism mediated by the two stilbenes could be related to their effect on bcl-2 gene family expression. Bax, a pro-apoptotic gene, resulted down-regulated by the treatment with rhaponticin and rhapontigenin compared with the results obtained in the presence of amyloid beta (1-42) peptide. Conversely, bcl-2, an anti-apoptotic gene, highly down-regulated by amyloid beta (1-42) treatment, resulted expressed in the presence of stilbenes similarly to that shown by control cells. The obtained results support the hypothesis that amyloid beta (1-42)-induced neurotoxicity occurs via bax over-expression, bcl-2 down-regulation, firstly indicating that rhaponticin and its aglycone moiety may alter this cell death pathway. Based on these studies, we suggest that rhaponticin and its main metabolite could be developed as agents for the management of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Degeneração Neural/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Placa Amiloide/efeitos dos fármacos , Estilbenos/farmacologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/toxicidade , Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Degeneração Neural/metabolismo , Degeneração Neural/fisiopatologia , Fármacos Neuroprotetores/uso terapêutico , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/toxicidade , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Placa Amiloide/metabolismo , Rheum/química , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Estilbenos/uso terapêutico
11.
Plant Physiol Biochem ; 44(10): 604-10, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17056265

RESUMO

A 23-kDa antifungal thaumatin-like protein was isolated and purified from Cassia didymobotrya (Fres.) cell cultures for the first time. The protein was secreted in the culture medium, but it could be also isolated after elution of whole cells with a 0.5 M CaCl(2) solution. Treatment of the cells with laminarin oligosaccharides or salicylic acid, but not with NaCl, resulted in enhancement of expression of the protein. A rapid purification protocol was used based on cationic exchange chromatography. The protein, with a highly basic character (pI 10), has an exact molecular mass of 23034 Da, as determined by MALDI-ToF mass spectrometry analysis. N-terminal sequencing of the intact polypeptide and the sequencing of two internal tryptic peptides indicated significant identity with other thaumatin-like proteins (TLP). The protein exerted antifungal activity towards some Candida species showing EC(50) values comparable to those of other antifungal TLPs. The collected data lead to classify this TLP as a new PR-5 protein.


Assuntos
Antifúngicos/metabolismo , Cassia/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Células Cultivadas , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular
12.
Clin Biochem ; 39(9): 888-92, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16806146

RESUMO

BACKGROUND: Vitamin D receptor (VDR) mediates the effects of vitamin D. Our paper evaluates the FokI and BsmI VDR genotypes in 246 Caucasian (Italian from Lazio Region) T1DM patients compared with 246 Caucasian healthy controls, sharing age and gender and regional provenience with the patients. In addition, T1DM patients without complications were compared with those carrying three complications. METHODS: Genotyping has been obtained by RFLP-PCR technique. RESULTS: A slight significant association of T1DM with FokI homozygous "f" genotype was observed. No association was observed with the presence of multiple complications by a multivariate analysis. CONCLUSION: T1DM patients showed slightly increased prevalence of "ff" VDR genotype.


Assuntos
Desoxirribonucleases de Sítio Específico do Tipo II/genética , Complicações do Diabetes/genética , Diabetes Mellitus Tipo 1/genética , Polimorfismo Genético , Adulto , Fatores Etários , Estudos de Casos e Controles , Nefropatias Diabéticas/genética , Neuropatias Diabéticas/genética , Retinopatia Diabética/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Regressão
13.
Minerva Stomatol ; 55(5): 297-305, 2006 May.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-16688106

RESUMO

AIM: Several studies have reported that dental resin-based materials release substances with biological activity: for this reason in this study we evaluated the in vitro cytopathic effects of a self-curing and a light-curing orthodontic composite resins by a cytotoxicity test. METHODS: The cytotoxic potential of specimens, prepared according to the manufacturer instructions, was evaluated using the thiazolyl blue tetrazolium bromide (MTT) assay on the mouse fibroblast cell line (3T3 Swiss) with 2 cells-material contact systems: the 24 h extracts method and the indirect toxicity method. RESULTS: The results obtained in this study elicit a close agreement between the 2 procedures; from the data obtained in the reported experimental conditions, it was possible to establish that the examined chemical-cured material is more cytotoxic than the light-cured one. CONCLUSIONS: From a clinical point of view, the photo-polymerizable resins are undoubtedly more useful in the daily practice, because of the larger precision of the bonding obtainable by the greater period available for setting the brackets before their lock. The results obtained in this study, even considering the limits of the in vitro tests, represent a further favourable feature of the light-curing composite resins. However, further investigations about the influence of polymerization methods of the materials on the biological effects are suggested to contribute to the determination of the best clinical operative conditions.


Assuntos
Resinas Acrílicas/toxicidade , Resinas Compostas/toxicidade , Poliuretanos/toxicidade , Resinas Acrílicas/efeitos da radiação , Animais , Sobrevivência Celular , Colorimetria , Corantes , Resinas Compostas/efeitos da radiação , Meios de Cultura , Colagem Dentária , Armazenamento de Medicamentos , Humanos , Técnicas In Vitro , Luz , Teste de Materiais , Camundongos , Braquetes Ortodônticos , Fotoquímica , Poliuretanos/efeitos da radiação , Aço , Células Swiss 3T3/efeitos dos fármacos , Sais de Tetrazólio , Tiazóis , Dente
14.
Int J Immunopathol Pharmacol ; 19(1): 57-66, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16569340

RESUMO

UNLABELLED: Insulin-like growth factor-1 (IGF-1) is involved in regulating the Th-1/Th-2 balance, favoring the development of the Th-2 compartment which enhances fibrosis, one of the main characteristics of Chronic Lung Disease (CLD) in premature newborns. Limited data is available concerning a possible association between early epithelial lining fluid (ELF) concentrations of IGF-1 (total and free forms), IGF-binding protein-3 (IGFBP-3), beta2-microglobulin and subsequent development of CLD in preterm neonates. If neutropenic, preterm neonates are frequently treated with recombinant human granulocyte colony stimulating factor (rhG-CSF). The objective of the study was to correlate ELF concentrations of IGF-1 and beta2 microglobulin during the first week of life both in non-neutropenic and in rhGCSF-treated neutropenic preterm neonates, with subsequent development in CLD. Thirty preterm neonates with Respiratory Distress Syndrome (6 with neutropenia) were studied. Eleven out of 24 non-neutropenic preterm infants (46%) and all of the six neutropenic subjects (100%) developed CLD. With the exception of first day values, there was a clear similarity in the behaviors of assayed molecules between non-neutropenic and neutropenic patients developing CLD. Non-neutropenic patients without CLD showed significantly lower values of free IGF-1 and beta2M both on days 1 and 3. Total IGF-I and cell counts were different only on the 3rd day. CONCLUSIONS: 1) the mechanisms leading to CLD might be mediated by high levels of IGF-family molecules soon after birth 2) beta2M could be a marker of increased bronchoalveolar lavage fluid cellularity with potential inflammatory properties 3) G-CSF treatment induces an increased synthesis of IGF-1 molecules by cells recruited in the lung, with possible enhancement of the fibrogenic mechanisms.


Assuntos
Células Epiteliais/metabolismo , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Recém-Nascido Prematuro/metabolismo , Fator de Crescimento Insulin-Like I/biossíntese , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Microglobulina beta-2/biossíntese , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Infecções por Chlamydia/tratamento farmacológico , Infecções por Chlamydia/microbiologia , Doença Crônica , Células Epiteliais/efeitos dos fármacos , Humanos , Recém-Nascido , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Neutropenia/tratamento farmacológico , Neutropenia/patologia , Fibrose Pulmonar/microbiologia , Proteínas Recombinantes , Infecções por Ureaplasma/tratamento farmacológico , Infecções por Ureaplasma/microbiologia , Ureaplasma urealyticum
15.
Biochem Biophys Res Commun ; 342(1): 206-13, 2006 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-16472763

RESUMO

The beta amyloid (Abeta), the major protein component of brain senile plaques in Alzheimer's disease, is known to be directly responsible for the production of free radicals toxic to brain tissue and the redox state of Met-35 residue seems to play a particular and critical role in peptide's neurotoxic actions. In this study, we investigated, in human neuroblastoma cells (IMR-32), the relationship between the oxidative state of methionine, and both neurotoxic and pro-apoptotic actions induced by Abeta-peptide, comparing the effects of native peptide, in which the Met-35 is present in the reduced state, with those of a modified peptide with oxidized Met-35 (Abeta(1-42)(35Met-ox)), as well as an Abeta-derivative with Met-35 substituted with norleucine (Abeta(1-42)(35Nle)). The obtained results show that Abeta induces a time-dependent decrease in cell viability; Abeta(1-42)(35Met-ox) was significantly less potent, though inducing a remarkable decrease in cell viability compared to control. On the contrary, no toxic effects were observed after treatment with Abeta(1-42)(35Nle). Abeta-peptide as well as the amyloid modified peptide with oxidized Met-35 induced the pro-apoptotic gene bax over-expression after 24 h, whereas Abeta(1-42)(35Nle) had no effect. Conversely, bcl-2, an anti-apoptotic gene, became highly down-regulated by Abeta peptide treatment, in contrast to that evidenced by the Abeta(1-42)(35Met-ox) peptide. Finally, Abeta caused an increase in caspase-3 activity to be higher with respect to that shown by Abeta(1-42)(35Met-ox) while Abeta(1-42)(35Nle) had no effect. These results support the hypothesis that Abeta-induced neurotoxicity occurs via bax over-expression, bcl-2 down-regulation, and caspase-3 activation, first indicating that methionine 35 redox state may alter this cell death pathway.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/farmacologia , Metionina/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Fragmentos de Peptídeos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína X Associada a bcl-2/genética , Peptídeos beta-Amiloides/química , Caspase 3 , Caspases/metabolismo , Morte Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mitocôndrias/efeitos dos fármacos , Neuroblastoma/genética , Fragmentos de Peptídeos/química
16.
J Cell Mol Med ; 9(2): 462-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15963265

RESUMO

Adopting biochemical and proteomic approaches, we investigated the effect of some PPAR-agonists, a new class of differentiating agents, on human hepatocellular carcinoma Hep-G2 cell line. Cancer differentiation was assayed by checking albumin, transferrin and alpha-fetoprotein synthesis. Cell metabolism was studied by NMR spectroscopy of cell culture supernatants and by evaluation of mitochondrial respiratory chain enzyme activities. The two dimensional electrophoresis approach was employed to analyze modifications in the expression of cellular proteins linked to cell phenotype differentiation in the attempt to identify potential diagnostic and prognostic biomarkers of hepatocellular carcinoma. Results indicate that PPAR-agonists are able to act as differentiating inducers in human hepatocellular carcinoma Hep-G2 cell line as well as to inhibit mitochondrial respiratory chain Complex I, provoking a selective derangement of cellular oxidative metabolism. Lastly, two dimensional electrophoresis showed interesting modifications in the pattern of expression of cellular proteins that confirm biochemical data (increase in albumin and transferrin, decrease of alpha-fetoprotein synthesis) and, moreover, emphasize the meaning of these data by the increase of spots indicatively ascribed to HSP70 and catalase.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Bezafibrato/farmacologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Catalase/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ácido Clofíbrico/farmacologia , Eletroforese em Gel Bidimensional , Genfibrozila/farmacologia , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Ácido Láctico/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NADH Desidrogenase/metabolismo , Proteômica/métodos , Albumina Sérica/metabolismo , Tiazolidinedionas/farmacologia , Transferrina/metabolismo , alfa-Fetoproteínas/metabolismo
17.
Luminescence ; 20(2): 73-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15702479

RESUMO

Cigarette smoking is known to be a risk factor for several chronic and neoplastic diseases. Many compounds formed by cigarette burning, ranging from particulate materials to water solutes and gaseous extracts, are considered to be noxious agents, and many biochemical and molecular mechanisms have been proposed for the toxic effects of cigarette smoke. The oral cavity and the upper respiratory tract represent the first contact areas for smoke compounds; even a single cigarette can produce marked effects on some components of the oral cavity, either chemical compounds, such as glutathione and enzymes, or cellular elements, such as polymorphonuclear leukocytes. Several studies suggest a protective role of glutathione against the noxious effects of tobacco smoke; the sulphydril groups of glutathione, in fact, could react with some smoke products, such as unsaturated aldehydes, leading to the formation of harmless intermediate compounds and simultaneously preventing the inactivation of metabolically essential molecules, such as some enzymes. In this paper we analyse the effect of a filter containing glutathione on the respiratory burst of polymorphonuclear leukocytes exposed to aqueous extract of cigarette smoke, measuring their chemiluminescence activity. The results of this paper indicate that the GSH-containing filter has a likely protective effect against the inhibition of cigarette smoke extract on polymorphonuclear leukocyte activity.


Assuntos
Glutationa/metabolismo , Medições Luminescentes , Neutrófilos/efeitos dos fármacos , Alcatrões/efeitos adversos , Filtração , Humanos , Neutrófilos/metabolismo , Fumar/efeitos adversos , Alcatrões/química , Fatores de Tempo
18.
Ann Hum Genet ; 68(Pt 6): 639-45, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15598222

RESUMO

Psoriasis is a chronic inflammatory disease of the skin with both genetic and environmental risk factors. Non-parametric linkage analyses have mapped many susceptibility loci on different chromosomes. We mapped one of these loci, PSORS4, on human chromosome 1q21. Using the linkage disequilibrium approach, we refined the critical region to a specific genomic interval of about 100 Kb which contains only the loricrin (LOR) gene. Here we report a genetic and functional study of this gene to verify its involvement in psoriasis pathogenesis. We document low expression of LOR in psoriatic skin of patients selected from families in which the disease was segregating with the PSORS4 locus. Re-sequencing of the entire gene in a subset of patients revealed the existence of novel polymorphisms able to influence the protein structure, as shown by molecular modelling studies. However, no evidence for genetic association was detected in a large cohort of Italian nuclear families. This rules out the LOR gene as a candidate for the PSORS4 locus.


Assuntos
Predisposição Genética para Doença , Proteínas de Membrana/genética , Psoríase/genética , Cromossomos Humanos Par 1 , Primers do DNA , Humanos , Modelos Moleculares , Estrutura Terciária de Proteína
19.
Acta Physiol Scand ; 182(3): 229-44, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15491403

RESUMO

The Bohr effect, i.e. the pH dependence of the oxygen affinity of haemoglobins (Hbs) from a variety of vertebrates, and its modulation by temperature and other heterotropic effectors has been reviewed. Haemoglobins from vertebrates were not reviewed following the usual classification (i.e. mammals, birds, etc.); instead we have selected several key examples of animals, which are confronted with a similar environmental situation therefore displaying a similar life style. Hence, the paper starts from a description of the general concepts at the basis of the Bohr effect as exemplified by human HbA and goes towards the analysis of the modulation mechanisms which have been observed in different animals in response to the needs induced by: (i) life in cold environments; (ii) diving behaviour; (iii) flight; and (iv) aquatic life. The emerging picture indicates a complex organization of the information contained in the Hb molecule, the oxygen-binding properties of which depend both on the intrinsic characteristics of the protein and on its heterotropic interactions with ligands such as protons (Bohr effect), small anions like chloride and organic phosphates. In addition, each one of the functional effects induced by binding of a given effector appears to be under the strict control of temperature that enhances or decreases its relative weight with respect to all the others. It is just by this sophisticated network of interactions that the Hb molecule is able to satisfy the physiological requirements of a multitude of organisms without changing dramatically its quaternary structure.


Assuntos
Hemoglobinas/fisiologia , Vertebrados/fisiologia , Adaptação Fisiológica/fisiologia , Anfíbios/fisiologia , Animais , Comportamento Animal/fisiologia , Aves/fisiologia , Temperatura Baixa , Meio Ambiente , Peixes/fisiologia , Voo Animal/fisiologia , Humanos , Concentração de Íons de Hidrogênio , Oxigênio/fisiologia
20.
Amino Acids ; 27(2): 187-91, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15503226

RESUMO

Oxidative stress is implicated in the pathogenesis of diabetes mellitus. Taurine and vitamin E+selenium supplementation has some benefits in experimental models of diabetes mellitus. This study evaluates whether taurine and vitamin E+selenium supplementations reduce a hard end-point such as mortality due to diabetes. Streptozotocin-induced diabetic rats were fed with standard diet or taurine (5%, w/w) or vitamin E (500 UI/Kg)+selenium (8 mg/Kg) enriched diets. Taurine significantly decreased mortality rate (p < 0.04), while vitamin E failed to increase survival. In the late phase of the disease, taurine significantly decreased glycaemia, being vitamin E ineffective. No correlation between glycaemia and survival was found. None of supplementations modified body weight. Thus, only taurine decreases the mortality rate and glycaemia. These results encourage new research in the field, since classical hypoglycaemic agents are unable to decrease mortality in diabetic patients.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/mortalidade , Estreptozocina/farmacologia , Taurina/química , Animais , Antioxidantes/metabolismo , Peso Corporal , Suplementos Nutricionais , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Fatores de Tempo , Vitamina E/farmacologia
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