RESUMEN
OBJECTIVE: The intestinal mucosa is known to be adversely affected by ischemia-reperfusion (I/R). Previously we showed that green tea protects the intestinal mucosa from fasting-induced damage. The aim of this study is to determine whether green tea has any protective role in I/R of the intestine. METHODS: Three groups of male rats were used in this study. Group I (I/R) underwent I/R of the intestine (30 min of ischemia followed by 1 h of reperfusion). Group II (green tea + I/R) was given green tea for 2 wk before inducing I/R. Group III (control) had sham I/R. After the experiments, the jejunum was removed and the tissues were processed for histopathologic examination and immunohistochemical analysis for cell proliferation markers and antioxidant enzymes. RESULTS: The intestinal mucosa in group II was preserved compared with that in group I. The expressions of cellular proliferation markers (proliferating cell nuclear antigen and Ki-67) and cellular antioxidants (superoxide dismutase and catalase) in group II were similar to those in group III and much less than in group I, reflecting the protective effects of green tea in group II animals. CONCLUSION: In this animal model, administration of green tea before inducing I/R protects the intestinal mucosa from injury.
Asunto(s)
Antioxidantes/farmacología , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control , Té/química , Análisis de Varianza , Animales , Biomarcadores , Catalasa/análisis , Proliferación Celular , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Yeyuno/efectos de los fármacos , Yeyuno/patología , Masculino , Modelos Animales , Ratas , Ratas Wistar , Daño por Reperfusión/fisiopatología , Superóxido Dismutasa/metabolismoRESUMEN
BACKGROUND: Green tea has been shown to repair fasting-induced mucosal damage in rat intestine. The aim of this study was to elucidate the underlying mechanism. METHODS: Five groups of rats were used. Group 1 had free access to chow diet and water, and those in group 2 were fasted for 3 days. Animals in group 3 were fasted for 3 days, then were allowed drinking water for a further 7 days. Groups 4 and 5 were fasted for 3 days, then given drinking water containing green tea or vitamin E respectively for 7 days. Blood was collected for estimation of total plasma antioxidants, and jejunal samples were used for immunohistochemical analysis of superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx), and for estimation of myeloperoxidase (MPO) activity. RESULTS: Use of green tea was associated with a significant increase in total plasma antioxidants (P < 0.001), and mucosal SOD (P < 0.001), catalase (P = 0.006) and GPx (P = 0.017), but a significant decrease in MPO activity (P < 0.001). Vitamin E produced similar changes, but the effects were smaller. CONCLUSION: Green tea reverses the fasting-induced damage to the intestinal mucosa by its antioxidant and anti-inflammatory effect.
Asunto(s)
Antioxidantes/metabolismo , Enteritis/tratamiento farmacológico , Ayuno/metabolismo , Enfermedades del Yeyuno/tratamiento farmacológico , Peroxidasa/metabolismo , Preparaciones de Plantas/farmacología , Té/fisiología , Animales , Catalasa/metabolismo , Enteritis/enzimología , Glutatión Peroxidasa/metabolismo , Inmunohistoquímica , Mucosa Intestinal/enzimología , Enfermedades del Yeyuno/enzimología , Yeyuno/enzimología , Masculino , Estrés Oxidativo , Fitoterapia , Distribución Aleatoria , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo , Vitamina E/farmacologíaRESUMEN
Feeding of 2% cholesterol diet increased lipid parameters in serum and tissues of rats during a period of one month. In addition to the above, lipid peroxidation also increased and activities of certain enzymes were significantly altered in the tissues. Similar changes were also observed to a greater extent with diets containing 40% by weight of coconut kernel or groundnut with and without 2% cholesterol. The enzymes studied were HMGCoA reductase, AST, ALT and ALP in tissues and serum as the case may be. In general the atherogenic effects were observed more with groundnut containing diets than those with coconut. Even though the oil from the former is mostly unsaturated and that from the latter is mostly saturated, these analytical criteria do not relate to their atherogenic effects. When 5% garlic was incorporated with any of the high fat diets, the lipid parameters, their peroxidation and alterations in enzyme activities were significantly decreased. These results show that garlic contains some principles that counteract the atherogenicity of the above oil seeds.