【作者】 吴雪伟；

【导师】 李敏；

【作者基本信息】 福建师范大学 ， 生物化学与分子生物学， 2005， 硕士

【摘要】 多不饱和脂肪酸(polyunsaturated fatty acids,PUFAs)是指含两个或两个以上双键的一类必需脂肪酸。在肥胖、糖尿病、心血管疾病和癌症方面具有生理功能。深黄被孢霉是一类富含亚油酸、亚麻酸的丝状真菌,具有重要的经济价值。脂肪组织是机体内最大的能量储存库,它是一种复杂的,高度活性的代谢和分泌器官,脂肪源性多肽激素leptin的发现使人们对脂肪组织的认识达到前所未有的高度。以脂肪组织为靶点探索肥胖与胰岛素抵抗的分子机制将有助于肥胖和Ⅱ型糖尿病的治疗。 本室已有报道深黄被孢霉对高脂血症或糖尿病动物模型有调血脂,降血糖功效,在此基础上,我们从分子水平上研究深黄被孢霉及其脂溶性组分对脂代谢紊乱和Ⅱ型糖尿病实验动物模型的分子机制。我们建立了脂代谢异常与Ⅱ型糖尿病小鼠模型,结果表明深黄被孢霉及其提取物对小鼠血清总胆固醇、甘油三酯、血糖有下调作用,且可升高血清高密度脂蛋白水平。我们分别选取了leptin、TNF-α、adiponectin与resistin四种脂肪细胞因子作为研究对象,通过半定量RT-PCR分析发现深黄被孢霉及其脂溶性组分对高脂饮食或Ⅱ型糖尿病小鼠附睾白色脂肪组织细胞因子leptin与adiponectin mRNA的表达有显著的升高作用,并可适度降低resistin mRNA转录水平,而对TNF-α的表达无显著影响。对脂肪组织的研究显示长期喂食深黄被孢霉及其脂溶性组分对部分脂肪细胞因子具有调节作用。更多还原

【Abstract】 Polyunsaturated fatty acids (PUFAs) are essential fatty acids for human life, and play pivotal physiological roles in obesity, diabetes, cardiovascular disease and cancer. The amount of study has suggested PUFAs have hypoglycemic and hypolipidemic effects by regulation of gene expression. In traditional view, adipose tissue is considered as a passive reservoir of energy storage. The discovery of leptin has focused attention on the role of cytokines secreted by adipose tissue, which is a complex, highly active metabolic and endocrine organ. A better understanding of adipose tissue in obesity and insulin resistance will likely permit rational approaches to treat obesity and type II diabetes.Mortierella isabelina is a filamentous fungi riched in linoleic acid and linolenic acid. This fungi has been shown to positively affect blood lipids and glucose. However, molecular mechanism of their effects on metabolic disease are unclear. In this study, we established diet-induced dyslipidemic and type II diabetic model to study the effects of Mortierella isabelina on the adipose tissue-derived cytokines, such as leptin, adiponectin, resistin, TNF-alpha. The result indicated that i) after 7-weeks administration of Mortierella isabelina, high fat diet-induced dyslipidemic mice led to body weight-loss, decreased epidydimal and perirenal white adipose tissue mass however no difference in interscapular brown white adipose tissue, reduced serum level of total cholesterol (TC), triglyceride (TG) and glucose, increased HDL-C level as well.ii) serum level of TC, TG and glucose were reduced in diabetic mice by administration of Mortierella isabelina and its PUFAs extraction, albeit no significantly difference. To further understand if Mortierella isabelina and its PUFAs extraction is the regulator of adipocytokines, we analyzed the epididymal white adipose tissue (WAT) from dyslipidemic or type II diabetic mice. The semi-quantitative RT-PCR has shown that Mortierella isabelina and PUFAs treatment significantly up-regulated leptin mRNA levels, the pattern of adiponectin mRNA regulation by fungi powder and PUFAs extraction was similar to that seen for leptin, and moderately down-regulated resistin transcript levels, though this change was更多还原