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排序方式: 共有395条查询结果,搜索用时 15 毫秒
1.
健身宝对衰老模型小鼠血清SOD和MDA的影响 总被引:2,自引:0,他引:2
目的 研究健身宝补脾益肾、延缓衰老的作用机制。方法 将 60只小鼠随机分为 6组 ,除正常对照组外均每日注射对D -半乳糖造成衰老模型 ,同时给予不同剂量的健身宝和金匮肾气丸。 6周后检测小鼠血清中SOD活性、MDA含量。结果 衰老模型组与正常对照组比较 ,小鼠血清中SOD活性显著降低 ,MDA含量显著升高 (P <0 .0 1 ) ;而健身宝大、中剂量组与正常对照组相比较 ,小鼠血清中SOD活性显著升高 ,MDA含量显著降低 ,与衰老模型组相比较有显著性差异 (P <0 .0 5 )。结论 健身宝明显提升D -半乳糖拟衰小鼠血清中SOD活性 ,降低MDA含量 ,可从调节自由基代谢和提高抗氧化能力方面发挥延缓衰老的作用。 相似文献
2.
Ning C Reynolds R Chen J Yager C Berry GT Leslie N Segal S 《Molecular genetics and metabolism》2001,72(4):306-315
Mice deficient in galactose-1-phosphate uridyltransferase (GALT) demonstrate abnormal galactose metabolism but no obvious clinical phenotype. To further dissect the pathways of galactose metabolism in these animals, galactose oxidation and metabolite levels were studied in 16-day-old sucklings and the effect of a 4 week prior exposure to a 40% glucose or 40% galactose diet was determined in 7-week-old mice. Suckling GALT-deficient (G/G) mice slowly oxidized [1-14C]galactose to 14CO2, 4.0% of the dose when fed and 7.9% when fasted compared to normal animals 38.3 and 36.4% in 4 h, respectively. Plasma of G/G sucklings contained 11.1 mM galactose and erythrocyte galactose 1-phosphate levels were 28.2 and 31.9 mg/dl packed cells. Galactose, galactitol, galactonate, and galactose 1-phosphate were found in G/G suckling mouse tissues. The tissue galactose concentrations were 10% or less of that in plasma, suggesting that there was limited cellular entry of galactose. In 7-week-old fasted mice with 4 weeks prior exposure to glucose or galactose-containing diet, 4-h oxidation was 12.9 and 15.0% of the administered radiolabeled galactose, respectively. Normal animals oxidized 33.9 and 37.9% of the dose when fed the same diets, respectively. The ability of G/G mice to oxidize galactose in the absence of GALT activity suggests the presence of alternate metabolic pathways for galactose disposition. G/G mice fed the galactose-free 40% glucose diet had erythrocyte galactose 1-phosphate levels ranging from 6.4 to 17.7 mg/dl packed cells and detectable galactose and galactose metabolites in tissues, suggesting that these animals endogenously produced galactose. The plasma of 40% galactose-fed G/G mice contained 9.1 mM galactose with red blood cell galactose 1-phosphate averaging 43.6 mg/dl. Tissues of these animals also contained high levels of galactose and galactose 1-phosphate. Liver contained over 4 micromol/g galactonate but little galactitol. Despite the elevated galactose and galactose 1-phosphate, the animals tolerated the high-galactose diet and were indistinguishable from normal animals, exhibiting no manifestations of galactose toxicity seen in human GALT-deficient galactosemia. The data suggest that high galactose 1-phosphate levels do not cause galactose toxicity and that high galactitol in combination with galactose 1-phosphate may be a prerequisite. Absence of GALT appears necessary but insufficient to produce human galactosemic phenotype. 相似文献
3.
β—淀粉样蛋白及D—半乳糖对大鼠学习记忆和胆碱酯酶活性?… 总被引:6,自引:0,他引:6
目的观察β-淀粉样蛋白(β-amyloid,Aβ)、D-半乳糖及两种药物联合使用时对大鼠学习记忆和大脑皮层胆碱酯酶活性的影响.方法D-半乳糖腹腔注射[50mg/(kg@d)],连续6周.在腹腔注射的第4周末,双侧海马内各注射Aβ1μl(含量为4μg).手术后2周,对各组大鼠进行开场行为、Y-型迷宫、被动回避测试及大脑皮层胆碱酯酶活性的测定.结果与对照组相比,D-半乳糖组、Aβ组、D-半乳糖加Aβ组大鼠的自主行为、学习记忆能力和大脑皮层胆碱酯酶的活性明显下降,尤其D-半乳糖加Aβ组明显.结论D-半乳糖、Aβ对大鼠的行为及中枢胆碱能系统均有明显抑制作用,二者联合作用时能产生更强的作用. 相似文献
4.
Dr. Carlo Merkel MD Angelo Gatta MD Marco Zoli MD Massimo Bolognesi MD Paolo Angeli MD Tiziana Iervese MD Giulio Marchesini MD Arturo Ruol MD 《Digestive diseases and sciences》1991,36(9):1197-1203
Seventy-eight patients with cirrhosis were prospectively followed for up to 20 months, on the average. At entry into the study, galactose elimination capacity, aminopyrine breath test, and ICG clearance were measured. At the end of the study, 27 patients had died. Univariate analysis using the Kaplan-Meier method showed that both quantitative liver function tests (galactose elimination capacity:P<0.025; aminopyrine breath test:P<0.001; ICG clearance:P<0.005) and common clinical and biochemical data (encephalopathy:P<0.001; ascites:P<0.001; serum bilirubin:P<0.005; serum albumin:P<0.001; prothrombin index:P<0.05) were significant predictors of survival. To investigate whether quantitative liver function tests could contribute to a better definition of the prognosis, once Pugh score had already been taken into account, a multiple regression analysis according to the Cox model was performed. Pugh score and galactose elimination capacity resulted in the only independent prognostic covariates. From them a prognostic index was calculated, and the model was validated in an additional sample of 70 patients investigated according to the same protocol. The contribution GEC gave to the assessment of overall prognosis over that obtained using the Pugh score was slight, as estimated by the statistical parameters of the Cox's model, but was significant as assessed by a ROC curve analysis (P=0.05). These data show that all quantitative liver function tests were predictors of survival in cirrhosis, and that the galactose elimination capacity added some new prognostic information to those already available using the Child-Turcotte-Pugh classification.This study was supported in part by a grant from the Italian Ministry of Education (National Project Liver Cirrhosis). Part of this study was presented at the 22nd Meeting of the European Society for Clinical Investigation, Graz, Austria, April 20–23, 1988. 相似文献
5.
目的 观察高浓度半乳糖诱导正常离体晶状体上皮细胞中游离钙的变化以及钙离子阻滞剂维拉帕米对它的阻滞作用。方法 钙离子指示剂fluo-3与离体的正常品状体上皮细胞中游离钙螯合后,用激光扫描共聚焦显微镜观察35mmol/L半乳糖在不同条件下致细胞内荧光强度的变化。结果 35mmol半乳糖作用于离体品状体上皮细胞后可见细胞内与钙离子的荧光强度呈持续上升趋势,各个细胞上升的幅度及反应的速度有细微差别,但100s左右均出现上升趋势。先加2mg/mL的维拉帕米,2min后加半乳糖溶液至终浓度为35mmol,观察5min只见基本正常的钙波动,未见明显的钙上升或下降改变。结论 半乳糖溶液能致离体晶状体上皮细胞中游离钙升高,维拉帕米能有效地抑制此过程。 相似文献
6.
Sato H Kato Y Hayasi E Tabata T Suzuki M Takahara Y Sugiyama Y 《Pharmaceutical research》2002,19(11):1736-1744
Purpose. To demonstrate the utilities of a synthetic low-affinity ligand ((Gal)3) for the asialoglycoprotein receptor (ASGP-R) as a hepatic targeting device for therapeutic cytokines.
Methods. The site-specific incorporation of (Gal)3 or a typical high-affinity ligand (GalNAc)3 into IL-2 was catalyzed by microbial transglutaminase. The anti-tumor activities, pharmacokinetic profiles and receptor-mediated endocytosis in hepatocytes of the ligand-IL-2 conjugates were examined in mouse.
Results. The (Gal)3 has approximately 50 times lower affinity to ASGP-R than (GalNAc)3. Nevertheless, the antitumor effects were in the order of (Gal)3—IL-2 > unmodified IL-2 > (GalNAc)3—IL-2. The systemic elimination and the hepatic uptake of (GalNAc)3—IL-2 were more rapid than (Gal)3—IL-2. The ratio of the rate constant representing dissociation from the cell-surface receptor (koff) to that representing endocytosis of the ligand (kint) was greater for (Gal)3—IL-2 than (GalNAc)3—IL-2, suggesting that (Gal)3—IL-2 preferably avoids internalization due to its lower affinity to the receptor. The simulation studies demonstrated that (Gal)3—IL-2 was present in the hepatic extracellular space for a longer period than (GalNAc)3 IL-2.
Conclusions. The (Gal)3 ligand increases the therapeutic efficacy of IL-2 by enhancing its exposure to the cell-surface. The koff/kint affects the targeting efficacy of the conjugates to ASGP-R. 相似文献
7.
Shuting Qiu Jiajia Chen Yan Bai Jincan He Hua Cao Qishi Che Jiao Guo Zhengquan Su 《Nutrients》2022,14(13)
The treatment of nonalcoholic fatty liver disease (NAFLD) remains very challenging. This study investigated the therapeutic effect of galactose oligosaccharide (GOS), an important prebiotic, on NAFLD through in vivo and in vitro experiments and preliminarily explored the mechanism by which GOS improves liver lipid metabolism and inflammation through liver and intestinal microbiological analysis. The results of mouse liver lipidomics showed that GOS could promote body thermogenesis in mice with high-fat and high-sugar diet (HFHSD)-induced NAFLD, regulate lipolysis in liver fat cells, and accelerate glycine and cholesterol metabolism. GOS dose-dependently reduced the contents of total cholesterol (TC) and triglyceride (TG) in cells and reduced the accumulation of lipid droplets in cells. GOS also reduced the Firmicutes/Bacteroidetes ratio and altered the composition of the intestinal microbiota in mice fed a HFHSD. GOS can improve liver lipid metabolism and intestinal structure of NAFLD. These results provide a theoretical and experimental basis supporting the use of GOS as a health food with anti-NAFLD functions. 相似文献
8.
Julia Holtmeier Maria Leuschner Arne Schneider Ulrich Leuschner Wolfgang F. Caspary 《Scandinavian journal of gastroenterology》2013,48(11):1336-1341
Objective. The 13C-methacetin breath test quantitatively evaluates cytochrome P450-dependent liver function. The 13C-galactose breath test non-invasively measures the galactose oxidation capacity of the liver. The aim of this study was to find out whether these breath tests are sensitive parameters also in non-cirrhotic patients with primary biliary cirrhosis.Material and methods. Nineteen patients with early-stage primary biliary cirrhosis (no cirrhotic alterations in the liver biopsy, Ludwig stage I–III) and 20 healthy controls underwent the 13C-methacetin and 13C-galactose breath tests.Results. Patients with primary biliary cirrhosis metabolized less 13C-methacetin than controls (cumulative recovery within 30 min 7.5±2.4% versus 14.0±2.6%; p<0.001). When a cut-off?>?9.8% was used for the cumulative recovery after 30 min, the methacetin breath test reached 84.2% sensitivity and 95.0 specificity. In the 13C-galactose breath test, the percentage recovery at 60 min in patients was 3.1±1.3%/h, and 6.3±1.1%/h in controls (p<0.001). Using a cut-off?>?4.7%/h, the galactose breath test reached 89.5% sensitivity and 95.0 specificity.Conclusions. In non-cirrhotic, early-stage, primary biliary cirrhosis the 13C-methacetin breath test and the 13C-galactose breath test reliably indicate decreased liver function. The 13C-galactose breath test can also predict the histological score. 相似文献
9.
《Scandinavian journal of gastroenterology》2013,48(2):197-200
Abstract Objective. Galactose elimination capacity (GEC) is used as a quantitative measure of liver metabolic function with prognostic value in adults with acute and chronic liver failure. Almost no data are available regarding GEC in children, however. This study thus aims to meet the previously unmet clinical need for age-related data on GEC in children. Material and methods. We studied galactose elimination in 10 healthy children (median age 10.7 years; range 7 months to 16 years) and 30 children with chronic liver disease (median age 8.6 years; range 3 months to 16 years). GEC was estimated from the linear decrease in concentration of galactose in arterialized capillary blood from the ear following intravenous infusion of galactose. Results. In both groups of children, GEC (μmol/min/kg body weight) was highest in the youngest children and decreased with age, although at a significantly lower level in the children with liver disease (p = 0.05). GEC was significantly higher in healthy children than in healthy adults, diminishing to the adult level by the age of 16 years. Conclusions. GEC was found to be higher in children than in adults until the age of 16 years. Moreover, GEC was significantly lower in children with chronic liver disease than in healthy children, underlining that GEC testing also has potential clinical usefulness as a quantitative measure of liver metabolic function in children. 相似文献
10.
目的探讨腹腔移植微载体粘附培养人肝细胞对D氨基半乳糖(DGal)诱导的急性肝衰竭小鼠的保护作用.方法采用胶原酶灌流法分离人肝细胞,胶原被覆的微载体Cytodex3加以培养,经腹腔注射2×106个肝细胞及载体,观察急性肝衰竭小鼠(n=32,25g/kgDGal诱导4h)72h存活率、血清ALT、总胆红素以及肝脏病理变化.结果与只接受微载体而无粘附肝细胞的对照组比较,腹腔移植培养肝细胞对肝衰竭小鼠的存活率有明显改善(65%vs0%),其血清ALT(IU/L,21744±2630vs42631±4928,P<005)及总胆红素(mmol/L,2691±376vs4168±383,P<005)较低.肝组织病理改变较轻.结论腹腔移植微载体粘附培养肝细胞可提供代谢支持,使DGal损伤的小鼠肝功能恢复. 相似文献