燕麦葡聚糖对高脂型大鼠肝功能及血脂水平的干预研究

目的观察燕麦葡聚糖对高脂型大鼠肝功能及血脂的影响。方法雄性SD大鼠随机分为对照组(普通饲料)和造模组(高脂饲料),连续喂养4周,将造模成功的大鼠随机分为模型组和燕麦葡聚糖低、中、高剂量组,连续灌胃4周,检测血及肝组织中谷草转氨酶(AST)、谷丙转氨酶(ALT)、总胆固醇(TC)、甘油三酯(TG)的活性或者含量。结果与模型组比较,燕麦葡聚糖组肝细胞损伤减轻,肝功能改善,中剂量燕麦葡聚糖组大鼠血清ALT、AST含量明显降低(P<0.05)。结论燕麦葡聚糖可降低高脂型大鼠血脂并能保护大鼠肝功能。

Coexistence of hyperlipidemia and acute cerebral ischemia/reperfusion induces severe liver damage in a rat model

AIM:To investigate the correlation of hyperlipemia(HL) and acute cerebral ischemia/reperfusion(I/R) injury on liver damage and its mechanism.METHODS:Rats were divided into 4 groups:control,HL,I/R and HL+I/R.After the induction of HL via a high-fat diet for 18 wk,middle cerebral artery occlusion was followed by 24 h of reperfusion to capture I/R.Serum alanine transaminase(ALT) and aspartate aminotransferase(AST) were analyzed as part of liver function tests and liver damage was further assessed by histological examination.Hepatocyte apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling(TUNEL) assay.The expression of genes related to apoptosis(caspase-3,bcl-2) was assayed by immunohistochemistry and Western blotting.Serum tumor necrosis factor-(TNF-),interleukin-1(IL-1) and liver mitochondrial superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA) and Ca 2+ levels were measured to determine inflammatory and oxidative/antioxidative status respectively.Microsomal hydroxylase activity of the cytochrome P450 2E1(CYP2E1)-containing enzyme was measured with aniline as the substrate,and CYP2E1 expression in the liver tissue and microsome was determined by immunohistochemistry and Western blotting respectively.RESULTS:HL alone induced by high-fat diet for 18 wk resulted in liver damage,indicated by histopathological analysis,and a considerable increase in serum ALT(25.13 ± 16.90 vs 9.56 ± 1.99,P < 0.01) and AST levels(18.01 ± 10.00 vs 11.33 ± 4.17,P < 0.05) compared with control.Moreover,HL alone induced hepatocyte apoptosis,which was determined by increased TUNEL-positive cells(4.47 ± 0.45 vs 1.5 ± 0.22,P < 0.01),higher caspase-3 and lower bcl-2 expression.Interestingly,compared with those in control,HL or I/R groups,massive increases of serum ALT(93.62 ± 24.00 vs 9.56 ± 1.99,25.13 ± 16.90 or 12.93 ± 6.14,P < 0.01) and AST(82.32 ± 26.92 vs 11.33 ± 4.17,18.01 ± 10.00 or 14.00 ± 6.19,P < 0.01) levels in HL+I/R group were observed suggesting severe liver damage,which was confirmed by liver histology.In addition,HL combined with I/R also caused significantly increased hepatocyte apoptosis,as evidenced by increased TUNEL-positive cells(6.20 ± 0.29 vs 1.5 ± 0.22,4.47 ± 0.45 or 1.97 ± 0.47,P < 0.01),elevated expression of caspase-3 and lower expression of bcl-2.Furthermore,when compared to HL or I/R alone,HL plus I/R enhanced serum TNF-,IL-1,liver mitochondrial MDA and Ca 2+ levels,suppressed SOD and GSH-Px in liver mitochondria,and markedly up-regulated the activity(11.76 ± 2.36 vs 4.77 ± 2.31 or 3.11 ± 1.35,P < 0.01) and expression(3.24 ± 0.38 vs 1.98 ± 0.88 or 1.72 ± 0.58,P < 0.01) of CYP2E1 in liver.CONCLUSION:The coexistence of HL and acute cerebral I/R induces severe liver damage,suggesting that cerebral ischemic stroke would exaggerate the damage of liver caused by HL.This effect is possibly due to en-hanced CYP2E1 induction which further promotes oxidative damage,inflammation and hepatocyte apoptosis.

Effect of Linguizhugan decoction on hyperlipidemia rats with intermittent fasting

OBJECTIVE:To explore the effect of Linguizhugan decoction on hyperlipidemia rats with caloric restriction.METHODS:The hyperlipidemia model of rat was induced by high fat diet for 8 weeks.After the model was established,26 rats were randomly divided into 4 groups:the control group(n=6),the model group(n=6),the intermittent fasting(IF) group(n= 8),and the IF and herbal medicine(IFH) group(n= 6).IF group was applied intermittent fasting every other day.The IFH group was given Linguizhugan decoction every day and intermittent fasting every other day.Blood samples were taken at the end of 16 weeks,and serum ghrelin and lipid was tested.RESULTS:Serum ghrelin in the IF group significantly increased(P<0.01).Serum ghrelin in IFH group was lower than the IF group(P<0.05),but higher than the model group(P<0.01).CONCLUSION:Linguizhugan decoction may play a part in regulation of energy and appetite in hyperlipidemia rats with IF.

Study on effects of Zhi Zi(Fructus gardeniae) on non-alcoholic fatty liver disease in the rat

OBJECTIVE:To investigate the effects of Zhi Zi(Fructus Gardeniae) on non-alcoholic fatty liver disease(NAFLD) induced by a high-fat diet in the rat.METHODS:A rat model of NAFLD was established using a high-fat diet.Twenty one rats were randomly divided into a normal group,a model group and a Zhi Zi treatment group,7 rats per group.Drinking water and the drug were intragastrically administrated for 5 weeks.Samples were then taken to observe pathological changes of the liver tissue(HE staining);changes in the fat metabolism pathway e.g.triglyceride(TG) and free fatty acid(FFA) content;alterations in liver function,i.e.serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) activity;and differences in tumor necrosis factor α(TNF-α) and P-IkB protein expression in the liver tissue.RESULTS:Fatty degeneration and vacuole-like changes of different degrees occurred in hepatic cells of the model group.Markers for fat metabolism,serum ALT and AST activities,and expressionof TNF-α and P-IkB proteins in liver tissue significantly increased.Fat metabolism in the Zhi Zi group significantly reduced,as shown by a drop in marker levels.Serum ALT and AST activities,and expression of TNF-α,P-IkB proteins in liver tissue were also significantly decreased in this group.CONCLUSION:Zhi Zi has a very strong inhibitory action on lipidosis and inflammatory injury in the rat model of NAFLD.This mechanism may possibly be related to the inhibition of the free fatty acid metabolism pathway.