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1.
J Biol Regul Homeost Agents ; 26(1): 39-49, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22475096

RESUMO

Osteoarthritis (OA) is the most frequently occurring rheumatic disease, caused by metabolic changes in chondrocytes, the cells that maintain cartilage. Treatment with electromagnetic fields (MF) produces benefits in patients affected by this pathology. Isolated human osteoarthritic (OA) chondrocytes were cultured in vitro under standard conditions or stimulated with IL-1beta or IGF-1, to mimic the imbalance between chondroformation and chondroresorption processes observed in OA cartilage in vivo. The cells were exposed for a specific time to extremely low frequency (ELF; 100-Hz) electromagnetic fields and to the Therapeutic Application of Musically Modulated Electromagnetic Fields (TAMMEF), which are characterized by variable frequencies, intensities, and waveforms. Using flow cytometry, we tested the effects of the different types of exposure on chondrocyte metabolism. The exposure of the cells to both systems enhances cell proliferation, does not generate reactive oxygen species, does not cause glutathione depletion or changes in mitochondrial transmembrane potential and does not induce apoptosis. This study presents scientific support to the fact that MF could influence OA chondrocytes from different points of view (viability, ROS production and apoptosis). We can conclude that both ELF and TAMMEF systems could be recommended for OA therapy and represent a valid non-pharmacological approach to the treatment of this pathology.


Assuntos
Condrócitos/metabolismo , Campos Eletromagnéticos , Osteoartrite/patologia , Idoso , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células , Células Cultivadas , Condrócitos/efeitos dos fármacos , Feminino , Glutationa/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Interleucina-1beta/farmacologia , Magnetoterapia/métodos , Masculino , Pessoa de Meia-Idade , Música , Osteoartrite/terapia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
2.
Nucleosides Nucleotides Nucleic Acids ; 27(6): 750-4, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18600536

RESUMO

Real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to evaluate gene expression of adenosine kinase, a key enzyme in adenosine metabolism, in human intestinal biopsy specimens of 10 colorectal cancer patients. Quantitative mRNA expression levels were normalized against the reference gene beta-actin. The results showed that adenosine kinase gene expression was significantly higher in cancer than in normal-appearing tissue, in line with our previous measurements of adenosine kinase enzyme activities in colorectal tumor samples.


Assuntos
Adenosina Quinase/genética , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Adenosina/metabolismo , Adenosina Quinase/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biópsia , Proliferação de Células , Neoplasias Colorretais/patologia , Feminino , Humanos , Intestinos/enzimologia , Intestinos/patologia , Masculino , Pessoa de Meia-Idade , Mucosa/enzimologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
3.
Nucleosides Nucleotides Nucleic Acids ; 27(6): 872-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18600555

RESUMO

Adenosine kinase is an enzyme catalyzing the reaction: adenosine + ATP --> AMP + ADP. We studied some biochemical properties not hitherto investigated and demonstrated that the reaction can be easily reversed when coupled with adenosine deaminase, which transforms adenosine into inosine and ammonia. The overall reaction is: AMP + ADP --> ATP + inosine + NH(3). The exoergonic ADA reaction shifts the equilibrium and fills the energy gap necessary for synthesis of ATP. This reaction could be used by cells under particular conditions of energy deficiency and, together with myokinase activity, may help to restore physiological ATP levels.


Assuntos
Adenosina Quinase/metabolismo , Fígado/enzimologia , Adenosina/metabolismo , Adenosina Desaminase/metabolismo , Amônia/metabolismo , Animais , Inosina/metabolismo , Cinética , Ratos , Especificidade por Substrato
4.
Biomed Pharmacother ; 61(2-3): 137-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17258885

RESUMO

Many studies have pointed out a possible role of gut peptides, including gastrin and ghrelin, in the pathogenesis and natural history of gastrointestinal malignancies, one of the most common death cause in the Western world. The objective of this work is to check gastrin and ghrelin serum levels in patients with colorectal cancer according to tumour's location, stage, Helicobacter pylori infection and BMI, in order to understand the two peptides' behaviour through the tumour's natural history and evaluate their assay's use in research and clinical practice. Twenty-nine subjects affected by colorectal cancer and 50 healthy controls were studied. Circulating gastrin and ghrelin levels and H. pylori serum antibodies were assessed by radioimmunologic assay and ELISA method. Gastrin and ghrelin serum levels were respectively slightly higher and significantly lower in colon cancer patients than in controls. Gastrin levels were higher in patients carrying left colon cancer and H. pylori infection while ghrelin levels were lower in both these groups. Both hormones' serum levels decreased from tumour earlier to later stages. Significant differences persisted in the correlation between BMI and ghrelin levels in controls but not in patients. Additional studies are necessary to ascertain the significance of gastrin and ghrelin opposite behaviour in colon cancer probably linked with interferences in endocrine pathways involving other gut peptides in this compromised condition.


Assuntos
Adenocarcinoma/sangue , Neoplasias Colorretais/sangue , Gastrinas/sangue , Infecções por Helicobacter/sangue , Helicobacter pylori , Hormônios Peptídicos/sangue , Adenocarcinoma/etiologia , Adenocarcinoma/microbiologia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos de Casos e Controles , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Grelina , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioimunoensaio
5.
Nucleosides Nucleotides Nucleic Acids ; 25(9-11): 1107-12, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17065073

RESUMO

Adenosine kinase is a well-known enzyme which catalyzes the phosphorylation of adenosine to AMP: Its metabolic and kinetic properties are well studied. Here, we report new properties of rat liver enzyme, demonstrating a new reaction: ADP can be a phosphate donor instead ATP, according to the reaction: adenosine + ADP --> 2AMP) demonstrating the efficiency of AdK to phosphorylate adenosine, also starting from ADP. Cells could exploited this property in situations in which ATP levels are strongly decreased and ADP decreases slowly.


Assuntos
Adenosina Quinase/fisiologia , Bioquímica/métodos , Fígado/enzimologia , Nucleotídeos/química , Difosfato de Adenosina/química , Difosfato de Adenosina/farmacologia , Adenosina Quinase/química , Monofosfato de Adenosina/química , Trifosfato de Adenosina/química , Animais , Catálise , Relação Dose-Resposta a Droga , Cinética , Fígado/metabolismo , Cloreto de Magnésio/farmacologia , Fosforilação , Purinas/química , Ratos
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