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51.
Rheum palmatum Linn has been widely applied in the clinical treatment of diabetes mellitus. It has been found that emodin as the major bioactive component of R. palmatum L exhibits the competency to activate peroxisomal proliferator-activated receptor-γ (PPARγ) in vitro. So the aim of this study was to evaluate the anti-diabetic effects of emodin through the activation of PPARγ on high-fat diet-fed and low dose of streptozotocin (STZ)-induced diabetic mice. The diabetic mice were intraperitoneally injected with emodin for three weeks. No changes of food consumption and the body weight in emodin-treated mice were monitored daily during the entire experiment. At the end of experiment, the levels of blood glucose, triglyceride and total cholesterol in serum were significantly decreased after emodin treatment. However, serum high-density lipoprotein cholesterol (HDLc) concentration was significantly elevated. The glucose tolerance and insulin sensitivity in emodin-treated group were significantly improved. Furthermore, the results of quantitative RT-PCR analysis showed that emodin significantly elevated the mRNA expression level of PPARγ and regulated the mRNA expressions of LPL, FAT/CD36, resistin and FABPs (ap2) in liver and adipocyte tissues. No effects on the mRNA expressions of PPARα and PPARα-target genes were observed. Taken together, the results suggested that the activation of PPARγ and the modulation of metabolism-related genes were likely involved in the anti-diabetic effects of emodin.  相似文献   
52.
The effect of inclusion of cashew globulin to a casein diet on lipid metabolism was studied in rats fed diets with two levels of cashew globulin meal. Inclusion of cashew globulin to a casein diet produced lower levels of total cholesterol, triacylglycerol and phospholipids in the serum and tissues and lower levels of serum lipoprotein cholesterol. There was decreased cholesterogenesis in the liver as evidenced by decreased activity of HMG CoA reductase and decreased release of lipoproteins into circulation. Rats fed cashew globulin along with casein also showed higher activity of LPL in the heart and adipose tissue and higher activity of LCAT. Increased hepatic diversion of cholesterol to bile acid synthesis and increased excretion of bile acids and sterols were also observed in these groups. Activity of glucose-6-phosphate dehydrogenase and malic enzyme was decreased in rats fed cashew globulin along with casein. This study demonstrates that cashew globulins included in the diet of rats are able to alter lipid metabolism which results in lower levels of lipid parameters in the serum and tissues.  相似文献   
53.
The aim of this study was to discriminate the impact of lighting and feeding conditions on the regulation of lipid metabolism in Ovis aries. Six clinically healthy female Comisana ewes, not pregnant and not lactating were kept under different environmental conditions: 12:12 light-dark (LD) cycle, constant darkness and fasting. Blood samples were collected at the end of each period of treatment every 4 h for a 24-h period. Blood concentration of triglycerides, total cholesterol and non-esterified fatty acid showed robust daily rhythmicity in ewes maintained under 12:12 LD cycle and fed ad libitum. Conversely, either constant darkness or fasting had a deep impact on all lipid parameters investigated. Our results suggest that lighting and feeding conditions have an impact on daily variations in lipid metabolism in ewes.  相似文献   
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55.
目的:了解单纯高脂饮食对小鼠肺组织形态学的影响及细胞凋亡抑制因子6(Api6)的表达情况.方法:将8周龄雄性C57BL/6小鼠随机分为2组,分别饲以普通饮食和高脂饮食,14周后获得上述2组小鼠的肺部组织切片,进行油红O染色、HE染色和免疫组化实验,观察单纯高脂饮食对小鼠肺组织形态学的影响;提取小鼠肺组织RNA,检测Api6在病变小鼠肺组织中的表达.结果:与普通饮食组小鼠肺组织相比,油红O染色可见高脂饮食组小鼠肺组织有明显的脂质沉积;HE染色和增殖期细胞核抗原(PCNA)免疫组织化学染色可见高脂饮食组肺组织肺泡间隔增宽,肺组织炎性细胞浸润,同时增殖期细胞明显增多;Api6在高脂饮食组小鼠肺组织中的表达明显升高.结论:高脂饮食可直接导致小鼠肺组织脂质蓄积和炎性损伤,Api6可能在其发病机制中发挥一定的作用.  相似文献   
56.
单核增生性李斯特杆菌感染和李氏溶血素   总被引:1,自引:0,他引:1  
单核增生性李斯特杆菌病能引起绵羊、人和其他很多动物疾病,在免疫学检测上有重要意义,在研究胞内菌感染的分子机制上也是一个重要的模型。但由于当前血清学试验上的非特异性和非敏感性,使李氏杆菌病的诊断和流行病学调查存在困难。在所有致病性的李斯特杆菌中,李斯特溶血素是主要致病因子,现已经有用其做诊断抗原的报道。文章论述了近年来单核增生性李斯特杆菌及李氏溶血素的最新进展,对研究李氏杆菌病的发病机理有一定作用。  相似文献   
57.
以我校教职工为全部受检对象,采集清晨空腹血样,通过对1 136例血浆中胆固醇(C)甘油三酯(TG)、高密度脂蛋白(HDL)水平进行检测,表明我校教职工从性别上看C、TG、HDL水平差异不显著,以45岁为界值,年龄在45岁以上各年龄组与年龄在45岁以下各年龄组相比差异极显著。结果表明:我校教职工血浆中胆固醇、甘油三酯随年龄的增长而递增,高密度脂蛋白的含量男性随年龄增长有所下降,而女性则随年龄的增长有所增加,这与正常人空腹血脂浓度受性别影响有关,但总体水平接近正常值,说明我校教职工饮食结构较为合理,身体比较健康。  相似文献   
58.
The effect of the administration of coriander seeds (Coriandrum sativum) on the metabolism of lipids was studied in rats fed a high fat diet with added cholesterol. The spice had a significant hypolipidemic action. The levels of total cholesterol and triglycerides decreased significantly in the tissues of the animals of the experimental group which received coriander seeds. Significant increases in -hydroxy, -methyl glutaryl CoA reductase and plasma lecithin cholesterol acyl transferase activity were noted in the experimental group. The level of LDL + VLDL cholesterol decreased while that of HDL cholesterol increased in the experimental group compared to the control group. The increased activity of plasma LCAT, enhanced hepatic bile acid synthesis and the increased degradation of cholesterol to fecal bile acids and neutral sterols appeared to account for its hypocholesterolemic effect.  相似文献   
59.
为了探索绵羊冷冻精液受精率低的原因,在稀释液中用低密度脂蛋白代替卵黄冷冻绵羊精液,研究LDL对冷冻中精子脂类含量的影响。结果表明,以卵黄稀释液冷冻精液,精子胆固醇含量从鲜精的234.54nmol/10^9降低到163.76nmol/10^9精子,胆固醇与磷脂的比值(c/p)从0.54下降到0.36;以9g/100mL LDL代替卵黄,冷冻后胆固醇含量为243.73nmol/10^9精子,c/p值保持在0.50。研究得出在卵黄稀释液中冷冻绵羊精液,精子胆固醇流失,c/p值下降;以LDL代替卵黄,可有效保护精子胆固醇,避免流失,维持了精子c/p值。  相似文献   
60.
三种乳酸菌降解鸡蛋胆固醇研究   总被引:1,自引:0,他引:1  
从发酵酸奶中扩增培养、分离纯化出嗜热链球菌、嗜酸乳杆菌和保加利亚乳杆菌3种乳酸菌.将菌株接种到鸡蛋液中.在37℃条件下恒温培养12、24、36 h后,用硫磷铁试剂分光光度法研究3种乳酸菌对鸡蛋中胆固醇降解的影响.结果表明,3种菌株均具有降解胆固醇的能力,在培养12 h内降解速率较快.24 h内降解率达到最大.在相同试验条件下,嗜热链球菌对鸡蛋胆固醇的降解能力最强.  相似文献   
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