RESUMO
OBJECTIVE@#To investigate the protective effects and potential mechanisms of tea polyphenols intervention on excess alcohol intake induced liver injury in rats. This study established the animal model of chronic liver injury rats induced by alcohol. Our results will provide experimental evidence for the effects of tea polyphenol on chronic alcoholic liver injury.@*METHODS@#Alcohol-induced liver injury rat models were established, and the tea polyphenols intervention was performed in the meantime. After 8 weeks, rats were anesthetized, and visceral fat and liver samples were separated, weighted and stored. Visceral fat content was evaluated in fat/body weight ratio. Liver lipid accumulation was assessed by liver index and the result of Oil Red O staining. Hepatic superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, total antioxidant capacity assay (T-AOC) and glutathione peroxidase (GSH-Px) activity were detected. And fatty acid translocase (FAT/CD36) protein level in liver was detected.@*RESULTS@#Compared with the control group rats, the fat/body weight ratio, SOD/MDA, T-AOC and GSH-Px activity of chronic liver injury rats were decreased significantly (<0.05,<0.01). Meanwhile the liver index, FAT/CD36 protein level and lipid deposition in liver of chronic liver injury rats were increased (<0.01). Compared with chronic liver injury rats, the tea polyphenols intervention increased fat/body weight ratio (<0.05), and significantly increased SOD/MDA, T-AOC and GSH-Px activity (<0.01). Meanwhile the tea polyphenols intervention reduced liver index (<0.01), FAT/CD36 protein level (<0.01) and lipid deposition in liver.@*CONCLUSIONS@#Tea polyphenols intervention can improve lipid deposition and oxidative stress in chronic alcoholic liver, which is concurrent with decreased FAT/CD36 protein expression on the hepatocyte membrane.
Assuntos
Animais , Ratos , Antioxidantes , Fígado , Malondialdeído , Polifenóis , Superóxido Dismutase , CháRESUMO
<p><b>OBJECTIVE</b>To investigate the effects of exercise (EX), low-fat diet (LFD) and their combination intervention on the tumor necrosis factor-alpha (TNF-alpha) expression of insulin resistance in rats.</p><p><b>METHODS</b>One hundred and thirty male rats randomly assigned to 2 groups: Control (CON)-10 rats consuming a low-fat diet; HFD-120 rats consuming a high-fat diet (HFD). The dietary regimen was sustained for 8 wk, at which point the 40 HFD group rats gaining the most weight were referred to as the obese rats. Glucose tolerance was assessed by an oral glucose tolerance test (OGTT). During the procedure of OGTT, the blood was drawn for insulin assay (insulin release test). The whole body insulin resistance was assessed by glucose-insulin index. The obese HFD group rats were randomized into one of four intervention groups: HFD-sedentary (HFD-SED), HFD-exercise(HFD-EX), low fat diet-SED (LFD-SED), LFD-EX. Ex rats performed 8-wk exercise training on a motorized treadmill. The CON group had access to low-fat diet for another 8 wk. After 8 wk of exercise and low-fat diet intervention, the OGTT and insulin release test were performed again. To use ELISA technique for detecting TNF-alpha in soleus muscle and adipose tissue.</p><p><b>RESULTS</b>After being fed high-fat diet for 8 wk, glucose-insulin index in the HFD group were significantly greater than that in CON group (P < 0.01). After 8-week exercise and low-fat diet intervention, glucose-insulin index in HFD-SED group was significantly greater than that in CON group (P < 0.01). The index in three intervention groups was significantly less than that in HFD-SED group (P < 0.01) . TNF-alpha content in adipose tissue and the soleus muscle for HFD-SED group was significantly greater than that in CON group (P < 0.01). Three intervention groups were significantly less than HFD-SED group (P < 0.01).</p><p><b>CONCLUSION</b>Exercise and low-fat diet interventions can decrease the TNF-alpha expression in insulin resistance rat.</p>