Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Mol Genet Metab ; 86(4): 473-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16288895

RESUMO

The Fanconi-Bickel syndrome is caused by homozygosity or compound heterozygosity for mutations of the facilitated glucose transporter 2 gene (GLUT2). Glycogen accumulates in renal tubular cells and they fail to reabsorb multiple filtered solutes because of impairment in GLUT2-mediated efflux of glucose. We describe a 10-year-old male child with GLUT2 deficiency who produced massive amounts of 3-deoxyfructose (3-DF) in the kidneys. Since 3-DF is a detoxification product of a potent glycating agent, 3-deoxyglucosone, a precursor of advanced glycation end-products, this suggests a massive accumulation of glucose within tubular cells probably as a consequence of GLUT2 deficiency. The level of 3-DF in the urine of this atypical patient, who also manifested renal glomerular hyperfiltration, microalbuminuria, and glomerular mesangial expansion, was higher than in any patient examined with diabetes mellitus. Elevated levels of glucose and/or its metabolites in renal tubular cells may be necessary but not sufficient for the development of both the renal tubulopathy and diabetic-like glomerular disease in GLUT2 deficiency.


Assuntos
Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/genética , Síndrome de Fanconi/complicações , Síndrome de Fanconi/genética , Transportador de Glucose Tipo 2/deficiência , Transportador de Glucose Tipo 2/genética , Adulto , Estudos de Casos e Controles , Criança , Análise Mutacional de DNA , Nefropatias Diabéticas/metabolismo , Síndrome de Fanconi/metabolismo , Humanos , Cetoses/urina , Masculino , Pessoa de Meia-Idade
2.
Diabetes ; 43(9): 1152-6, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8070616

RESUMO

3-Deoxyglucosone (3-DG) is a reactive dicarbonyl sugar thought to be a key intermediate in the nonenzymatic polymerization and browning of proteins by glucose. 3-DG may be formed in vivo from fructose, fructose 3-phosphate, or Amadori adducts to protein, such as N epsilon-fructoselysine (FL), all of which are known to be elevated in body fluids or tissues in diabetes. Modification of proteins by 3-DG formed in vivo is thought to be limited by enzymatic reduction of 3-DG to less reactive species, such as 3-deoxyfructose (3-DF). In this study, we have measured 3-DF, as a metabolic fingerprint of 3-DG, in plasma and urine from a group of diabetic patients and control subjects. Plasma and urinary 3-DF concentrations were significantly increased in the diabetic compared with the control population (0.853 +/- 0.189 vs. 0.494 +/- 0.072 microM, P < 0.001, and 69.9 +/- 44.2 vs. 38.7 +/- 16.1 nmol/mg creatinine, P < 0.001, respectively). Plasma and urinary 3-DF concentrations correlated strongly with one another, with HbA1c (P < 0.005 in all cases), and with urinary FL (P < 0.02 and P = 0.005, respectively). The overall increase in 3-DF concentrations in plasma and urine in diabetes and their correlation with other indexes of glycemic control suggest that increased amounts of 3-DG are formed in the body during hyperglycemia in diabetes and then metabolized to 3-DF. These observations are consistent with a role for increased formation of the dicarbonyl sugar 3-DG in the accelerated browning of tissue proteins in diabetes.


Assuntos
Diabetes Mellitus/sangue , Cetoses/sangue , Cetoses/urina , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Biomarcadores/urina , Glicemia/análise , Diabetes Mellitus/urina , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/urina , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/urina , Hemoglobinas Glicadas/análise , Humanos , Lisina/análogos & derivados , Lisina/urina , Pessoa de Meia-Idade , Valores de Referência , Análise de Regressão
3.
Arch Biochem Biophys ; 294(1): 130-7, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1550339

RESUMO

3-Deoxyglucose (3-deoxy-D-erythro-hexos-2-ulose) (3-DG) is a reactive dicarbonyl intermediate involved in the polymerization and browning of proteins by glucose in vitro. Damage to protein by formation of 3-DG in vivo is thought to be limited by enzymes which convert 3-DG to less reactive species, such as 3-deoxyfructose (3-DF). We have developed a sensitive and specific assay for measuring 3-DG and 3-DF in human urine and plasma. In this assay, 3-DG and 3-DF are reduced to 3-deoxy-hexitols (3-DH), using either NaBH4 or NaBD4, and then analyzed by selected ion monitoring gas chromatography-mass spectrometry. Based on comparative analysis of samples reduced with NaBD4 versus NaBD4, 3-DH in urine was derived exclusively (greater than 99%) from 3-DF, while 3-DG accounted for approximately 15% of 3-DH in plasma. The concentrations of 3-DH in fasting human urine and plasma were 5.3 +/- 1.5 micrograms/mg creatinine (n = 18) and 7.2 +/- 1.7 micrograms/dl (n = 18), respectively. The concentrations of 3-DG and 3-DF in plasma (n = 7) were 1.0 +/- 0.2 and 6.7 +/- 1.6 micrograms/dl, respectively. These results suggest that several milligrams of 3-DG are formed in the body per day and detoxified by reduction to 3-DF and support the role of 3-DG as an intermediate in the browning of protein via the Maillard reaction in vivo.


Assuntos
Cetoses/análise , Reação de Maillard , Boroidretos , Desoxiglucose/análogos & derivados , Desoxiglucose/análise , Desoxiglucose/sangue , Desoxiglucose/urina , Deutério , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Cetoses/sangue , Cetoses/urina , Estrutura Molecular , Oxirredução , Proteínas/química
5.
Vopr Med Khim ; 25(2): 153-7, 1979.
Artigo em Russo | MEDLINE | ID: mdl-442586

RESUMO

Simultaneously with fructose and sucrose, five oligosaccharides, containing fructose residue and exhibiting reducing properties, were found in urine of patients with chronic pancreatitis and with liver impairments caused by ethanol intoxication. Four of the oligosaccharides were trisaccharides, containing fructose residue and two residues of glucose as well as one tetrassaccharide, comprizing a residue of fructose and three residues of glucose. The fructose residue occupied the terminal position in all the oligosaccharides. The oligosaccharides found in urine of the patients were dissimilar in the types of link between residues of glucose and between residues of fructose and glucose; these oligosaccharides exhibited different chromatographic mobility.


Assuntos
Cetoses/urina , Pancreatite/urina , Doença Crônica , Frutose/urina , Humanos , Masculino , Oligossacarídeos/urina , Sacarose/urina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...