【作者】 吴涛；

【导师】 郑晓冬；

【作者基本信息】 浙江大学 ， 食品科学， 2014， 博士

【摘要】 肥胖不仅是一种危害健康的慢性病,而且是Ⅱ型糖尿病、心脑血管疾病、癌症等多种慢性疾病重要的危险因素,因而现已成为全球首要的健康问题。现有的治疗肥胖的方法大都存在降低机体免疫力、毒副作用大、易反弹等缺点。因此,寻找一种安全的减肥方法成为科研工作者努力的方向。花色苷是一种水溶性天然色素,隶属于多酚类化合物,相关研究表明它具有抗肿瘤、抗炎及降血脂等生物活性。因此探究花色苷对肥胖的干预作用具有十分重要的意义。本课题从桑果、樱桃、蓝莓、蓝靛果四种水果中分离制备花色苷,运用3T3-L1前脂肪细胞模型探讨了桑果、樱桃、蓝靛果花色苷对前脂肪细胞的增殖与分化的抑制作用；运用高脂膳食诱导肥胖动物模型评价了不同来源花色苷对肥胖小鼠的膳食干预作用,初步探讨了花色苷干预肥胖的相关机制。所得主要成果如下：(1)桑果果汁、蓝莓果汁可抑制高脂膳食C57BL/6小鼠体重的增加。膳食桑果果汁、蓝莓果汁12周小鼠体重分别减轻了9.8%和7.3%,此外,两种果汁均可减少脂质在血清和肝脏组织的积累、改善胰岛素抵抗、下调炎症因子IL-6TNF-α基因表达水平,推测多酚类物质花色苷起重要作用。(2)分离纯化得到桑果、蓝莓、樱桃、蓝靛果花色苷,证实了桑果花色苷由矢车菊素-3-葡萄糖糖苷,矢车菊素-3-芸香糖苷,花葵素-3-芸香糖苷组成；樱桃中花色苷主要由矢车菊素-3-(2G-葡萄糖基芸香糖)苷和矢车菊素-3-芸香糖苷组成；蓝莓花色苷主要成份是矮牵牛素-3-阿拉伯糖苷、飞燕草素-3-半乳糖苷、矢车菊素-3-半乳糖苷、锦葵素-3-葡萄糖苷；蓝靛果花色苷由矢车菊素-3-葡萄糖苷,矢车菊素芸-3-香糖苷,矮牵牛素-3-葡萄糖苷,花葵素-3-葡萄糖苷组成。(3)桑果花色苷、樱桃花色苷、蓝莓花色苷对3T3-L1前脂肪细胞增殖和分化具有抑制作用,可诱导3T3-L l前脂肪细胞的凋亡。100μg/mL处理前脂肪细胞24h后,三种花色苷对3T3-L1前脂肪细胞增殖的抑制率分别为39.6%,40.2%,20.3%；200pg/mL处理前脂肪细胞后,三种花色苷对3T3-L1前脂肪细胞的分化抑制率分别为28.3%,30.7%,37.6%。(4)膳食桑果、甜樱桃、蓝莓花色苷均可抑制高脂膳食C57BL/6小鼠体重增加。高低剂量桑果花色苷对高脂膳食C57BL/6小鼠体重增加的抑制率分别为11.8%,21.4%;高低剂量樱桃花色苷对高脂膳食C57BL/6小鼠体重增加的抑制率为分别为11.1%,23.6%;高低剂量蓝莓花色苷对高脂膳食C57BL/6小鼠体重增加的抑制率为8.1%,12.6%;研究发现三种来源的花色苷均有修复肝损伤、改善胰岛索抵抗、减少脂质在肝脏和血清中积累的生理活性。(5)探讨了桑果、樱桃、蓝莓、蓝靛果花色苷对高脂膳食诱导肥胖C57BL/6小鼠的干预作用,研究发现四种来源花色苷并不能改变肥胖组小鼠体重增加的趋势,仅能抑制小鼠体重增加幅度。膳食200mg/kg四种花色苷其体重增加的抑制率分别为32.7%,29.6%,19.4%,24.1%。进一步证实花色苷具有降低血清及肝脏中脂质的积累作用。(6)花色苷可以显著升高SOD及GPx活性;下调FAS、PPARγ、基因及炎症相关因子IL-6、TNF-α、NF-κB、iNOS、IFNγ基因表达水平,显著上调CPT-1基因的表达。(7)推测花色苷干预肥胖的机制可能与抑制脂肪酸合成相关基因的表达;上调脂肪酸氧化基因的表达;降低肥胖相关炎症因子的分泌有关。更多还原

【Abstract】 Obesity is now acknowledged as a leading global health problem that causes detrimental effects. This condition is known to contribute to the risk of various chronic diseases such as type Ⅱ diabetes mellitus, coronary heart disease, hypertension, and several types of cancer. Currently available pharmaceuticals for obesity treatment have a number of limitations such as adverse effects and high rates of secondary failure. Therefore, natural products having anti-obesity effects are now being arranged into anti-obesity stategy. Anthocyanins are water-soluble plant polyphenolic pigments. Recently, these substances have attracted scientists’ interest because of their non-toxicity and healthy benefits, including anti-tumor, anti-inflammatory, reduce hematic lipids. etc. This study aimed to isolate and characterize anthocyanins from mulberry, sweet cherry, blueberry and honeysuckle; investigate their inhibitory influences on the profiferation and differentiation of3T3-L1proadipocytes; evaluate the effect of the different anthocyanin supplementation on high fat diet-induced obese animal model, including intervention and treatment experiment; study the mechanism of their effect on weight loss preliminarily. The results were as follows:(1) Mulberry juice and blueberry juice suppressed the body weight gain of high fat diet fed mice. Among the12weeks experiment perioed, intake mulberry or blueberry juice reduced body weight mice weight9.8%and7.3%respectively. Furthermore, both of juice supplementation could significantly reduce lipids accumulation in serum and liver tissue, improve insulin resistance, lower inflammatory cytokines gene expressions, such as IL-6, TNF-α. The polyphenols pigments, anthocyanins may play important part in the benefical function.(2) Anthocyanins from mulberry, sweet cherry, blueberry and honeysuckle have been isolated and characterized. There are three kinds of anthocyanin in mulberry anthocyanin, which are Cyanidin-3-glucoside, Cyanidin-3-rutinoside and Pelargonidin-3-glucoside. Sweet cherry anthocyanins mainly composed with Cyanidin-3-(2G-glucosylrutinoside), Cyanidin-3-rutinoside and Pelargonidin-3-rutinoside. The major anthocyanins in blueberry anthocyanins were Petunidin-3-arabinoside, Delphinidin-3-galactoside, Cyanidin-3-galactoside and Pelargonidin-3-glucoside. Honeysuckle anthocyanins composed with Cyanidin-3-glucoside, Cyanidin-3-rutinoside, Peonidin-3-glucoside and Pelargonidin-3-glucoside.(3) The results indicated that anthocyanins from mulberry, sweet cherry and blueberry could inhibit the profiferation and differentiation of3T3-L1proadipocytes, induce the cell apoptosis. Treated the preadipocytes with the three kinds anthocyanins100μg/mL for24h, the inhibiton ratio on preadipocytes proliferation was39.6%,40.2%and20.3%respectively. In3T3-L1preadipocytes differentiation exper iments, it was found that three kinds of anthocyanins at200μg/mL-1could inhibit preadipocyte differentiation by28.3%,30.7%and37.6%respectively.(4) Dietary supplementation with anthcyanins from mulberry, sweet cherry or blueberry suppressed the body weight gain of high fat diet fed mice. After the12weeks experiment, intake anthocyanins from mulberry at low dose or high dose reduced body weight gain by11.8%and21.4%respectively. Consumption sweet cherry anthocyanins at low dose or high dose prevented body weight gain by11.8%and21.4%respectively. Supplementation of blueberry anthocyanins at at low dose or high dose inhibited body weight gain by8.1%and12.6%respectively. The study exhibited that all the three sources of anthocyanins could impaired hepatic function, reduce the resistance to insulin, decrease the lipids accumulation in serum and liver tissue, etc.(5) In obesity treatment experiment, the effects of anthocyanins from mulberry, sweet cherry, blueberry and honeysuckle on wight loss were investigated. We found that anthocyanins does not change the trend of great body weight, but slow the body weigt gain. Cosumption anthocyanins from mulberry, sweet cherry, blueberry and honeysuckle could prvent body weight gain by32.7%,29.6%,19.4%,24.1%respectively. Furthermore, the obesity treatment experiment also confirmed a phenomenon that anthocyanins could reduce the accumulation of lipid in serum and liver function.(6) Anthocyanins supplementation significantly increase the heapatic SOD and GPx activity, up-regulation the experession of CPT-1genes, down-regulation the expression of FAS、PPARγ genes and inflammation factor genes, such as IL-6TNF-α、NF-κB、iNOS、IFNγ gene.(7) The mechanisms of anthocyanin exert anti-obestiy effects possibly associated with inhibition of fatty acid synthesis, increase the oxidation of fatty synthesis and decrease the production of inflammatory.更多还原