Deficiency in glutathione synthesis and reduction contributes to the pathogenesis of colitis-related liver injury / 中南大学学报(医学版)

OBJECTIVES@#Liver disease is the most common extra-intestinal manifestation of ulcerative colitis (UC), but the underlying pathogenesis is still not clarified. It is well accepted that the occurrence of UC-related liver disease has close correlation with immune activation, intestinal bacterial liver translocation, inflammatory cytokine storm, and the disturbance of bile acid circulation. The occurrence of UC-related liver disease makes the therapy difficult, therefor study on the pathogenesis of UC-related liver injury is of great significance for its prevention and treatment. Glutathione (GSH) shows multiple physiological activities, such as free radical scavenging, detoxification metabolism and immune defense. The synthesis and the oxidation-reduction all contribute to GSH antioxidant function. It is reported that the deficiency in hepatic GSH antioxidant function participates in multiple liver diseases, but whether it participates in the pathogenesis of UC-related liver injury is still not clear. This study aims to investigate the feature and underlying mechanism of GSH synthesis and oxidation-reduction function during the development of UC, which will provide useful information for the pathogenesis study on UC-related liver injury.@*METHODS@#UC model was induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS)-ethanol solution (5 mg/0.8 mL per rat, 50% ethanol) via intra-colonic administration in rats, and the samples of serum, liver, and colon tissue of rats were collected at the 3rd, 5th, and 7th days post TNBS. The severity degree of colitis was evaluated by measuring the disease activity index, colonic myeloperoxidase activity, and histopathological score, and the degree of liver injury was evaluated by histopathological score and the serum content of alanine aminotransferase. Spearman correlation analysis was also conducted between the degree of colonic lesions and index of hepatic histopathological score as well as serum aspartate aminotransferase level to clarify the correlation between liver injury and colitis. To evaluate the hepatic antioxidant function of GSH in UC rats, hepatic GSH content, enzyme activity of GSH peroxidase (GSH-Px), and GSH reductase (GR) were determined in rats at the 3rd, 5th, and 7th days post TNBS, and the protein expressions of glutamine cysteine ligase (GCL), GSH synthase, GSH-Px, and GR in the liver of UC rats were also examined by Western blotting.@*RESULTS@#Compared with the control, the disease activity index, colonic myeloperoxidase activity, and histopathological score were all significantly increased at the 3rd, 5th, and 7th days post TNBS (all P<0.01), the serum aspartate aminotransferase level and hepatic histopathologic score were also obviously elevated at the 7th day post TNBS (all P<0.05). There was a significant positive correlation between the degree of liver injury and the severity of colonic lesions (P=0.000 1). Moreover, compared with the control, hepatic GSH content and the activity of GSH-Px and GR were all significantly decreased at the 3rd and 5th days post TNBS (P<0.05 or P<0.01), and the protein expressions of GCL, GSH-Px, and GR were all obviously down-regulated at the 3rd, 5th, and 7th days post TNBS (P<0.05 or P<0.01).@*CONCLUSIONS@#There is a significant positive correlation between the degree of liver injury and the severity of colonic lesions, and the occurrence of reduced hepatic GSH synthesis and decreased GSH reduction function is obviously earlier than that of the liver injury in UC rats. The reduced hepatic expression of enzymes that responsible for GSH synthesis and reduction may contribute to the deficiency of GSH synthesis and oxidation-reduction function, indicating that the deficiency in GSH antioxidant function may participate in the pathogenesis of UC related liver injury.

O impacto da fibrose cística no perfil imunológico de pacientes pediátricos / The impact of cystic fibrosis on the immunologic profile of pediatric patients

OBJETIVO: Comparar o estado imunológico de 44 pacientes pediátricos com fibrose cística (FC)a umgrupo-controle formado por 16 indivíduos saudáveis. MÉTODOS: Foram selecionados para o estudo pacientes com FC com idade entre 3 e 12 anos, apresentando um escore clínico moderado e bom. Foram avaliados a glutationa eritrocitária, a produção de espécies reativas de oxigênio, citocinas (TNF-α, IFN-γ, IL-8, IL-6, IL-10) em culturas de células mononucleares do sangue periférico em condições espontâneas e estimuladas por BCG ou PHA, a concentração sérica de TGF-β2, IgA, IgG, IgM, IgE e IgA salivar. RESULTADOS :A produção espontânea de TNF-α, IL-6 e IL-10, a produção de IL-6 estimulada por PHA e TGF-β2, IgA e IgG séricas aumentaram em amostras de pacientes com FC. Indivíduos saudáveis tiveram uma produção mais elevada de TNF-α em resposta a BCG. CONCLUSÃO: Apesar de os pacientes com FC parecerem clinicamente estáveis, os resultados de seus exames de sangue periférico mostraram que houve um impacto sobre o sistema imunológico.

OBJECTIVE: To compare the immunologic state of 44 pediatric patients with cystic fibrosis (CF) with a control group consisting of 16 healthy individuals. METHODS: CF patients aged 3 to 12 years with moderate to good clinical score were selected for the study. Erythrocytic glutathione, production of reactive oxygen species, cytokines (TNF-α, IFN-γ, IL-8, IL-6, IL-10) in peripheral blood mononuclear cells cultures under spontaneous and BCG- or PHA-stimulated conditions, serum concentrations of TGF-β2, IgA, IgG, IgM, IgE, and salivary IgA were evaluated. RESULTS: The spontaneous production of TNF-α, IL-6, and IL-10, the PHA-stimulated production of IL-6, and the serum TGF-β2, IgA, and IgG were increased in samples from CF patients. Healthy subjects had a higher production of TNF-α in response to BCG. CONCLUSION: Although CF patients appearedclinically stable, the results of their peripheral blood examinations demonstrated an impact on the immune system.

Glutathione and cysteine biosynthesis in two varieties of Abelmoschus esculentus in response to mine spoil.

The extent of accumulation of some heavy metals and glutathione and cysteine levels in the roots and aerial plant parts in two genotypically different varieties of A. esculentus (KS404 and BO2) exposed to mine spoil were investigated. Glutathione (GSH) level in both the varieties on control sites increased from basal level to 155.15 nmol g(-1) dry weight (d.wt.), almost 1.5 fold on 30 day and attained a plateau within 60 day Mine spoil exposure of both the varieties decreased glutathione 1.13 fold (89.2 nmol g(-1) dry weight) during 60 day from its basal level. GSH concentration in shoots of these varieties increased accompanying growth contrary to roots where it finally declined 2 fold. Cysteine content in control plants increased 2 fold (31.6 nmol g(-1) dry weight) on 30 day and finally declined 1.38 fold (22.35 nmol g(-1) dry weight, at 60 day). Both the varieties, when exposed to mine spoil, showed enhanced cysteine content almost 2 fold during 30 day (50.95 nmol g(-1) dry weight) but failed to increase further Forshoots in both the varieties challenged with mine spoil, cysteine maxima reached late (15.2 nmol g(-1) dry weight, at 40 day) relative to control but the levels declined subsequently (11.85 nmol g(-l) dry weight). Contrary to GSH, cysteine content in roots of both the varieties responded positively to mine spoil as apparent from the 2.23 fold increase during 30 d than basal level although it lowered to a level of 12.85 nmol g(-1) dry weight finally at 60 day. Both the varieties accumulated almost maximum level of selected cations (Fe > Mn> Zn> Cu > Ni) during 30 day, but BO2 variety was significantly superior in this regard. Invariably high accumulation of such cations in roots over shoots indicated accumulation, retention or restricted translocation from root to shoot. The metal share of the edible part was just 6% of the plant load. Thus, present work reflects a genotypic differences in metal accumulation and that affected the major non-enzymatic traits or synthesis of sulthydryl compounds as well. The present results also indicate that metal tolerance is in part associated with anti-oxidant system activity.

Metabolismo del glutatión y desarrollo posnatal del pulmón de la rata / Glutathione metabolism during postnatal development of the rat lung

Background: Significant changes in lung antioxidants occur in preparation for birth. Little is known about physiological regulation of antioxidants in the postnatal period. Aim: To study the glutathione system in the lungs during postnatal development. Material and methods: In the lungs of 7, 15, 21, 50 and 70 days old Sprague-Dawley rats we measured total and oxidized glutathione content as well as the activity of the limiting enzyme in glutathione synthesis (y-GCS) and of the enzymes glutathione peroxidase (GPx) and glutathione reducíase (GRd). Results: Between 7 and 15 days the activities of GPx and GRd increase 32 percent and 26 percent, respectively (p <0.001). Whereas GPx activity remains high throughout the rest of the study period, GRd activity decreases progressively reaching adulthood values at 7 days. y-GCS activity shows a gradual increase that reaches significance at 50 days when it doubles values observed at 7 days (p <0.05). A significant correlation was found between GPx and GRd activities over the entire period (r =0.62, p <0.0001). Strength of the correlation is age dependent due to the differences in time course of the enzyme changes. Whereas total GSH does not change, oxidized glutathione decreases from 7 percent at 7 and 15 days to 4 percent later on (p <0.01). Conclusions: The activity of several enzymes involved in glutathione metabolism increases during postnatal development of the rat lung. Interpretation of lung responses to injurious agents needs to be done taking into consideration the physiological regulation of antioxidants during postnatal development.

Caracterizaçäo e detecção de adutos entre 2'-desoxiguanosina e trans, trans-2,4-decadienal / Caracterization and detection of adduct between 2'-deoxyguanosine and trans, trans-2,4-decadienal

Vários adutos resultantes da reação de aldeídos `alfaï,ß-insaturados, ou de seus epóxidos, com bases do DNA têm sido caracterizadas nos últimos anos. Esses adutos podem levar à incorporação errada de bases durante a replicação ou a transcrição, resultando, se não reparados, em mutações que podem contribuir para a carcinogênese. O trans,trans-2,4-decadienal (DDE) é um dos aldeídos mais citotóxicos gerados endogenamente a partir da peroxidação lipídica. Verificamos que este aldeído afeta a viabilidade e altera o nível de glutationa de células CV1-P, além de induzir fragmentação do DNA e formação de diferentes produtos com o mesmo. Além da sua formação endógena, DDE é também encontrado em alguns alimentos, contribuindo para o aroma dos mesmos...

Desnutrição na gestação e lactação altera a atividade da `gamaï-glutamiltranspeptidase e os níveis de glutationa em glândula mamária de ratas / Malnutrition during gestation and lactation changes `gamma'-glutamyltranspeptidase activity and glutathione levels in mammary gland of rats

O papel desempenhado pela `gamaï-glutamiltranspeptidase (GGT - EC 2.3.2.2.) no transporte de aminoácidos e na mobilização de cisteína da glutationa (GSH) justifica o interesse em avaliar suas respostas à desnutrição protéico-calórica durante o processo gestacional e de lactação. Para estudar as alterações na atividade da enzima e nos níveis de GSH, fêmeas prenhes e virgens receberam dietas controle (caseína-13 por cento) e restrita em proteína (caseína-6 por cento). Após 22 e 32 dias de experiência, correspondendo ao 1º e 10º dias de lactação, procedeu-se ao sacrifício e determinou-se GGT e GSH na glândula mamária das mães e no fígado de mães e filhotes. Elevação significativa na atividade da enzima nas mamas das ratas desnutridas foi observada no 1º dia de lactação, acompanhada de redução também significativa no conteúdo de GSH, tendo-se verificado correlação negativa entre esses parâmetros e entre a GGT e o CEA...

Glutatión sanguíneo en el paciente alcohólico con hepatopatía / Blood glutathione in the alcoholic patient with hepatopathy

Dada la gran importancia del glutatión como indicador de la reserva antioxidante tisular y en vista de la existencia de datos contradictorios en la literatura internacional, se decidió cuantificar la concentración del glutatión oxidado y del reducido en muestra de sangre de 18 individuos no bebedores y de 52 enfermos alcohólicos. El diagnóstico de los enfermos se hizo por medio de la clínica y estudios de laboratorio, lo que permitió agruparlos en tres grados crecientes de severidad de acuerdo al índice de Orrego. Se observó que existe un abatimiento de los niveles de glutatión total en sangre que es mayor conforme más severo es el daño hepático. El glutatión reducido en sangre, que es la fracción útil como antioxidante, muestra una disminución paralela al glutatión total; mientras que se observa un aumento en la fracción oxidada del glutatión sanguíneo, que guarda relación con la severidad del daño hepático. Se concluye que la determinación del glutatión total, así como sus fracciones reducida y oxidada, puede servir para conocer la reserva antioxidante en la sangre y probablemente en el organismo y con ello contribuye a evaluar las posibilidades de recuperación de los pacientes alcohólicos

Efecto de la furazolidona sobre el glutatión sanguíneo del pollo de engorda / Effec of furazolidone on chicks blood glutathione

El objetivo de este trabajo fue establecer si la furazolidona utiliza el sistema detoxificante de glutatión en el organismo, mediante la determinación de la cantidad (µmol/ml de sangre) de glutatión total (GT), glutatión oxidado (GSSG), y glutatión reducido (GSH) durante las 5 semanas de vida del pollo de engorda que no consumió aditivos (testigo), comparado con los niveles de GT, GSSG y GSH sanguíneo de las aves que consumieron furazolidona durante las 5 primeras semanas de vida. Hubo diferencia significativa entre el GT (µmol/ml de sangre) y el peso corporal de pollos del grupo testigo y el que consumió furazolidona (55 ppm en el alimento) (R²= -0.709; P< 0.05, y = 2.15 - 0.607x y R²=-0.820 P< 0.05, y = 2.17 -0.61x respectivamente) hubo diferencia significativa (P< 0.05) entre el peso de los pollos del grupo testigo y el de los que consumieron furazolidona (751.3 vs 884.35 g respectivamente)

Effect of cadmium on tissue glutathione and glutathione peroxidase in rats: influence of selenium supplementation.

Administration of cadmium (2.5 mg/kg, sc on alternate days for 3 weeks) to male albino rats led to significant accumulation of cadmium and metallothionein in the liver and kidneys. The activity of glutathione peroxidase was significantly decreased whereas, the concentration of glutathione was increased in these organs. Glycine-l-14C incorporation studies showed enhanced synthesis of glutathione in kidney but not in the liver. Selenium supplementation (1 mg/kg/day orally) failed to prevent these cadmium-induced changes, although it resulted in very high accumulation of selenium in these organs indicating the formation of cadmium-selenium complex.

Glutathione and glutathione reductase in anaemia of malignancy

To verify the role of glutathione in the incidence of anaemia in malignancy, 56 subjects were admitted in this study and classified into 5 groups: 20 healthy subjects [group I], 10 patients with cancer urinary bladder [group II], 10 patients with cancer breast [group III], 10 patients with acute lymphoblastic leukaemia [A.L.L.] [group IV] and 6 patients with other different malignancies [group V]. All subjects were subjected to the following investigations: complete blood count [C.B.C.], reticulocyte count, determination of reduced and oxidized glutathione [G.S.H] and GSSG] in red cells and plasma, G.S.H. stability test, quantitative determination of glutathione reductase enzyme [G.R.] in red cells and plasma and quantitative determination of glucose 6-phosphate dehydrogenase [G-6PD]. Alteration in enzyme activity in plasma G.R. in A.L.L. cases and in various malignancies with or without chemotherapy was obtained. Plasma G.S.S. stability were elevated significantly in cases under chemotherapy. Another significant alteration was found in red cell G6PD in cases of A.L.L. and cancer cases receiving chemotherapy. We conclude from this study that the alterations found in malignancy may affect the state of anaemia. Oxidized glutathione [GSSG] could be used as a guide for prognosis in malignant cases as it was changed only after chemotherapy, together with glutathione stability [GSH stab.]

SIDA y antioxidantes / AIDS and antioxidants

Este artículo está dedicado a discutir diversas evidencias descritas recientemente en la literatura, sobre correlaciones que establecen importantes hallazgos experimentales entre el virus de la inmunodeficiencia humana (VIH) y los niveles de antioxidantes, como el glutation (GSH), tanto en el plasma como en el fluido broncoalveolar, en pacientes asintomáticos, seropositivos. Se analiza también el uso de antioxidantes como una posible terapia de prevención, con el objeto de impedir el desarrollo de la enfermedad, así como los mecanismos que conducen a una depleción de glutation