双歧醋对高脂饮食大鼠血脂的影响

目的 探讨双歧醋对高脂饮食大鼠血脂的影响作用.方法 48只SD大鼠被随机分成双歧醋低剂量组[1.8 mL/( kg·BW)]、中剂量组[3.4 mL/(kg · BW)]、高剂量组[6.8 mL/(kg · BW)]和市售醋组[3.4 mL/( kg·BW)]、高脂模型组以及正常组,观察双歧醋对高脂饮食大鼠血脂的影响作用,测定指标包括大鼠体重、肝指数、体脂指数、病理学观察肝脏脂肪变性等.结果 实验结果显示,双歧醋各组所有测定指标值都较高脂模型组有明显好转,特别是甘油三酯(TG)和高密度脂蛋白胆固醇(HDL-C)水平双歧杆菌醋的高、中量组与市售醋组比较差异有统计学意义(P＜0.05).结论 双歧醋能有效预防高脂饮食大鼠的血脂水平升高,对预防体重、肝指数升高和肝脏脂肪变性也有一定作用.     

双歧杆菌降胆固醇的作用机制

双歧杆菌是现在食品药品市场被广泛应用的一种菌株,它生理功能的优势及对人体的益处被人们认可。尤其是其在脂类代谢中的降胆固醇功能在各种研究中均得以证实。本研究就双歧杆菌的降胆固醇机制及具有此功能的双歧杆菌产品等方面进行论述,为今后对双歧杆菌的研究提供参考及思路。     

双歧杆菌改善实验性高脂血症小鼠记忆的研究

目的探讨双歧杆菌对高胆固醇血症小鼠记忆的影响。方法采用灌胃法建立小鼠高脂血症模型及双歧杆菌实验组（低、中、高浓度分别为10^6、10^8、10^9CFU／ml）。连续灌胃40d后,测定小鼠记忆能力,并检测血清脂质水平及全血和血浆的高、中、低切流变学测定。结果在实验期内造成高脂模型,与对照组比较,高脂小鼠记忆明显降低,而双歧杆菌组明显改善高血脂小鼠记忆能力,同时降低小鼠全血的高、中、低切粘度,与模型组相比差异均有显著性（P〈0．01）。结论双歧杆菌可以改善实验性高脂小鼠的记忆,其机制可能与其降低小鼠全血粘度有关。     

双歧杆菌对小鼠肠道树突状细胞数量的影响

目的研究双歧杆菌对小鼠肠道树突状细胞(dendritic ce ll,DC)数量的影响。方法分别采用活双歧杆菌菌液(1×109CFU/m l)、灭活双歧杆菌菌液(1×109CFU/m l)、双歧杆菌耗尽培养上清(Spen t cu lturesupernatan t,SCS)、无菌生理盐水给BALB/c小鼠灌胃,均为0.5 m l/(只.d),连续7 d,取小肠空、回肠段,SP免疫组织化学法分析检测肠道DC数量。结果DC分布于整个空、回肠的黏膜固有层。细胞大小不一,外形不规则,胞核外形亦不规则,多数呈偏心位,且DC有不规则突起,与周围细胞有紧密的接触。计数发现,双歧杆菌灌胃后小鼠小肠黏膜固有层DC数量增加(P<0.05),以活菌作用最明显,死菌次之,培养上清作用最弱,经统计学处理差异有显著性(P<0.05)。结论外源性双歧杆菌能增加小鼠小肠黏膜固有层中DC的数量,活菌作用最明显。提示双歧杆菌通过胃肠道途径可能影响DC的分化、发育;对DC的作用可能就是双歧杆菌影响机体免疫功能的重要环节;且保持活菌状态对机体免疫有重要作用。     

双歧杆菌对小鼠溃疡性结肠炎模型的影响

目的：研究双歧杆菌对小鼠急性溃疡性结肠炎模型的影响。方法：葡聚糖硫酸钠（DSS）制备小鼠溃疡性结肠炎模型。应用实体显微镜观察整段大肠的粘膜改变情况;普通粪便涂片观察小鼠粪便中细菌的变化,梯度稀释法行粪便菌群分析,了解几种代表性的菌群的改变;一般病理切片,行HE染色,观察镜下病理变化,结果：双歧杆菌 DSS组相比,血便不明显,镜下组织病理改变轻微,肠道菌群无明显紊乱。结论：双歧杆菌对溃疡性结肠炎发生有预防作用,并能减轻症状和病变。     

双歧杆菌复合制剂对脂质代谢的影响

本实验观察了双歧杆菌复合制剂（三株口服液）对高脂血症患者脂质代谢的影响。结果表明,用药第２周血清胆固醇和甘油三酯即开始下降,４周效果明显（Ｐ＜０．０５）,同时高密度脂蛋白也逐渐上升。它说明三株口服液确有改善脂质代谢紊乱的作用。     

双歧醋对高脂饮食大鼠血脂影响的机制探讨

目的 探讨双歧醋对高脂饮食大鼠血脂的影响机制.方法 48只SD大鼠被随机分成双歧醋低剂量组[1.8 mL/(kg·BW)]、中剂量组[3.4 mL/(kg· BW)]、高剂量组[6.8 mL/(kg·BW)]和市售醋组[3.4 mL/(kg·BW)]、高脂模型组以及基础对照组,观察双歧醋对高脂饮食大鼠血脂的影响作用机制,测定指标包括大鼠肝脏脂质、大鼠LDLR的免疫组化分析,HMGCoA还原酶和LDLR的RT-PCR分析.结果 双歧醋各组对于HMGCoA还原酶表达有抑制作用,但可以上调LDLR的基因和蛋白质表达.结论 双歧醋可以通过调节HMGCoA还原酶和LDLR的表达预防高脂饮食大鼠高血脂的发生.     

双歧杆菌发酵果蔬汁对小鼠免疫功能的影响

目的研究双歧杆菌发酵果蔬汁对小鼠免疫功能的影响。方法将小鼠随机分成纯净水对照组与发酵果蔬汁低、中和高3个剂量组,饮水法喂饲小鼠,测定小鼠胸腺和脾脏指数、腹腔巨噬细胞吞噬功能、血清溶血素测定、皮肤迟发型超敏反应(DTH)程度。结果与对照组比较,3种果蔬汁能显著增强巨噬细胞吞噬功能,增加血清溶血素抗体水平和DTH程度。结论双歧杆菌发酵果蔬汁能提高机体的免疫功能。     

双歧杆菌小鼠肠道定植的优化

目的评价自制的小鼠灌肠器灌肠效果,并探讨双歧杆菌定植的优化方式,更好地建立双歧杆菌在结肠的定植模型。方法选用SPF级C57BL小鼠40只,每组10只,随机分成4组：正常对照组,常规灌胃组,市售灌肠组,自制灌肠组。从市面不同的材料中筛选小鼠灌肠管,并设计小鼠专用灌肠器。记录不同灌注方式时隐血试验等一般指标检测。RT-PCR检测4组脾脏TLR2 mRNA表达水平。免疫组化观察颈动脉血管HGF蛋白水平。体外模拟不同pH值检测双歧杆菌定植HT-29细胞的粘附水平。结果自制的灌肠器在小鼠灌肠操作过程中明显优于市售灌肠器;自制灌肠组隐血试验明显低于市售灌肠组（P〈0.01）;RT-PCR结果显示,自制灌肠组效果最强,市售灌肠组次之,常规灌胃组一般,但均高于正常对照组;HGF的免疫组化显示,自制灌肠组表达最强;粘附试验显示双歧杆菌在pH 7.0环境中粘附能力优于pH 4.5。结论双歧杆菌在结肠定植采用灌肠方式优于灌胃方式;自制灌肠器优于市售灌肠器;优化灌肠液,采用自制的灌肠器灌肠同时优化灌肠操作,能够在小鼠结肠建立较好的双歧杆菌定植模型。     

双歧杆菌发酵果蔬汁对小鼠免疫调节机制的研究

目的研究双歧杆菌发酵果蔬汁对小鼠免疫调节作用的机制。方法将小鼠随机分成纯净水对照组、非发酵果蔬汁组和发酵果蔬汁低、中、高三个剂量组,饮水法喂饲小鼠30d,检测小鼠脾细胞的增殖能力及T淋巴细胞亚群,ELISA法测定血清IL-6和IFN-γ水平。结果发酵果蔬汁可增强小鼠脾细胞的增殖能力,T细胞表面标志CD3、CD4、CD8表达增强,促进血清中IL-6和IFN-γ的生成。结论双歧杆菌发酵果蔬汁能提高小鼠的体液、细胞免疫和非特异性免疫功能,并呈剂量效应关系。     

The effect of taurine on cholesterol degradation in mice fed a high-cholesterol diet

The hypocholesterolemic effect of taurine was examined in mice fed a high-cholesterol diet containing 1% cholesterol and 0.25% sodium cholate. Male C57BL/6 mice were divided into 3 groups: control group (HC), 1% taurine-supplemented group (HCT+), and taurine-deficient group (HCT-) produced by supplying 0.5% guanidinoethyl sulfonate (GES) solution ad libitum instead of water. After they were fed with the respective diet or drinking water for 4 weeks, the liver taurine level was reduced 80% in the HCT- group compared with that in the HC group, although there was no difference in the serum taurine amount between the two groups. The formation ratio of cholesterol gallstones increased from 71% to 100% by taurine deficiency, and decreased to 0% by taurine supplementation. Compared with the HC group, serum and liver cholesterol significantly decreased, and the excretion of fecal bile acid notably rose in the HCT+ group but tended to lower in the HCT- group. There were no differences in LDL receptor protein level among the three groups. In the subsequent experiment, triglycerides (TG) secretion rate was determined and found to be significantly suppressed by taurine supplementation. In conclusion, it is suggested that taurine does not up-regulate LDL receptor protein level, and the decrease in cholesterol in the circulation is mainly due to its suppressive effect on TG secretion from the liver.     

肠球菌WZM05对高胆固醇血症小鼠载脂蛋白的影响

目的探讨肠球菌WZM05对高胆固醇血症小鼠血清学指标及高胆固醇血症形成的影响。方法采用灌胃法建立小鼠高胆固醇血症模型及肠球菌实验组（10^6、10^8、10^9CFU／m1）,实验40d后,进行血清血脂水平检测及载脂蛋白A1（apoAI）、载脂蛋白B（apoB）测定。结果肠球菌组的血清总胆固醇明显降低,高密度脂蛋白明显升高（P〈0．01）,血清apoAI升高及apoB降低（P〈0．05）。结论肠球菌WZM05具有降脂、调脂作用。     

Pivotal role of cAMP in the activation of liver glycogen breakdown in high-fat diet fed mice

Aims

Liver glycogen catabolism was evaluated in male Swiss mice fed a high-fat diet rich in saturated fatty acids (HFD) or normal fat diet (NFD) during one week.

Main methods

Liver glycogenolysis (LG) and liver glucose production (LGP) were measured either under basal or stimulated conditions (infusion of glycogenolytic agents). Thus, isolated perfused livers from HFD and NFD mice were infused with glycogenolytic agents, i.e., glucagon, epinephrine, phenylephrine, isoproterenol, adenosine-3′-5′-cyclic monophosphate (cAMP), N⁶,2′-O-dibutyryl-cAMP (DB-cAMP), 8-bromoadenosine-cAMP (8-Br-cAMP) or N⁶-monobutyryl-cAMP (N6-MB-cAMP). Moreover, glycemia and liver glycogen content were measured.

Key findings

Glycemia, liver glycogen content and basal rate of LGP and LG were not influenced by the HFD. However, LGP and LG were lower (p < 0.05) in HFD mice during the infusions of glucagon (1 nM), epinephrine (20 μM) or phenylephrine (20 μM). In contrast, the activation of LGP and LG during the infusion of isoproterenol (20 μM) was not different (HFD vs. NFD). Because glucagon showed the most prominent response, the effect of cAMP, its intracellular mediator, on LGP and LG was investigated. cAMP (150 μM) showed lower activation of LGP and LG in the HFD group. However, the activation of LGP and LG was not influenced by HFD whether DB-cAMP (3 μM), 8-Br-cAMP (3 μM) or N6-MB-cAMP (3 μM) were used.

Significance

The activation of LGP and LG depends on the intracellular availability of cAMP. It can be concluded that cAMP played a pivotal role on the activation of LG in high-fat diet fed mice.     

Effects of live Lactobacillus paracasei on plasma lipid concentration in rats fed an ethanol-containing diet

The protective effects of live Lactobacillus paracasei NFRI 7415 on alcoholic liver disease were investigated. Male Fischer 344 rats were fed a control diet (CD), an ethanol diet (ED) (35.8% of total energy from ethanol), or an ethanol diet containing 20% live Lb. paracasei NFRI 7415 (10(7) cfu/g) (LD) for 10 weeks. The results indicated that live Lb. paracasei NFRI 7415 reduced the total cholesterol concentration of the plasma and liver in the rats fed the LD. The level of docosahexaenoic acid (DHA; 22:6n-3) in the plasma and liver of the LD group was higher than in the ED group. Chronic alcohol consumption decreased the level of n-3 fatty acid in the plasma and liver of the ED group. These results indicated that live Lb. paracasei NFRI 7415 can adjust the fatty acid composition of the plasma and liver, and that it is possible to decrease liver damage due to chronic alcohol intake.     

Caveolin-1 deficiency alters plasma lipid and lipoprotein profiles in mice

Caveolae are specialized membrane microdomains formed as the result of local accumulation of cholesterol, glycosphingolipids, and the structural protein caveolin-1 (Cav-1). To further elucidate the role of Cav-1 in lipid homeostasis in-vivo, we analyzed fasting and post-prandial plasma from Cav-1 deficient mice on low or on high fat diet. In total plasma analysis, an increase in ceramide and hexosylceramide was observed. In cholesteryl ester (CE), we found an increased saturated + monounsaturated/polyunsaturated fatty acid ratio in fasting plasma of low fat fed Cav-1(−/−) mice with increased proportions of CE16:1, CE18:1, CE20:3, and decreased proportions of CE18:2 and CE22:6. Under high fat diet HDL-CE, free cholesterol and pre-β-HDL were increased accompanied by a shift from slow to fast migrating α-HDL and expansion of apoE containing HDL. Our results demonstrate a significant role of Cav-1 in HDL-cholesterol metabolism and may reflect a variety of Cav-1 functions including modulation of ACAT activity and SR-BI function.     

Effect of dietary chitosans with different viscosity on plasma lipids and lipid peroxidation in rats fed on a diet enriched with cholesterol

To investigate the effect of dietary chitosan on lipid metabolism, male SD (Sprague-Dawley) rats were fed a cholesterol-enriched diet containing 5% cellulose (CE), 5% chitosan (CCS; high viscosity), or 5% chitosan (FCS; low viscosity) for 4 weeks. The two types of chitosan with a comparable degree of deacetylation had a different molecular weight and intrinsic viscosity. Significantly (p < 0.05) lower plasma total cholesterol, LDL-cholesterol and VLDL-cholesterol concentrations were observed in the rats fed on the chitosan diets. In addition, chitosan significantly increased the fecal cholesterol and triglyceride contents. Although no significant difference in body weight was found among the dietary groups, the rats fed on the chitosan diets had lower relative liver weight when compared with those fed on the cellulose diet. Both of the chitosan groups had significantly lower liver total lipid and total cholesterol contents compared to the cellulose group, although the FCS group was less effective. The plasma and liver thiobarbituric acid reactive substances (TBAR) values were similar in the CE and FCS groups, while the CCS group had increased liver TBAR values. Although a significant increase in liver glucose-6-phosphate dehydrogenase activity was observed in the CCS group, no significant change was found in the FCS group. The observed influence of chitosans with different viscosity on the plasma lipid level, liver lipids and lipid peroxidation suggests that, while the hypocholesterolemic action of chitosans with different viscosity was similar, changes in the liver lipids and liver peroxidation status depended on their molecular weight when the deacetylation degree was comparable.