玛咖对2型糖尿病降糖作用及机理研究

发布时间：2018-04-26 08:52

本文选题：玛咖 + 芥子油苷　；参考：《中国科学院大学(中国科学院过程工程研究所)》2017年博士论文

【摘要】：玛咖(Lepidiummeyenii,maca),原产于南美洲安地斯山脉的一种十字花科独行菜属植物。2007年以来,相继在中国云南、四川、新疆等地区试种成功,仅云南的种植面积就达到20万亩以上。有型糖尿病患者食用玛咖后发现其血糖下降,但玛咖为何能降糖却不清楚。本论文采用体外、细胞及动物实验,系统研究玛咖中降糖活性物质及其降血糖机理,为拓展玛咖在降糖产品开发中应用奠定基础。主要研究结果如下:(1)分离纯化了芥子油苷、黄酮采用超声循环提取玛咖,通过D101大孔树脂和IRA-67离子交换树脂纯化芥子油苷,得到纯度78.3%以上的玛咖芥子油苷;通过大孔树脂AB-8和聚酰胺两步纯化,得到纯度89.2%的玛咖总黄酮。(2)玛咖黄酮、芥子油苷抑制α-葡萄糖苷酶活性效果明显玛咖黄酮、芥子油苷对α-葡萄糖苷酶具有抑制作用。玛咖黄酮的IC50为0.41 mg/mL,属于竞争性抑制和非竞争性抑制的混合型抑制;玛咖芥子油苷的IC50为0.73 mg/mL,属于竞争性抑制。对Caco-2细胞内α-葡萄糖苷酶也有显著的抑制效果,玛咖总黄酮的IC50为0.21 mg/mL,玛咖芥子油苷的IC50为0.33 mg/mL。(3)玛咖能改善Hep-G2肝细胞胰岛素抵抗模型糖异生代谢采用Hep-G2细胞胰岛素抵抗模型研究表明:玛咖黄酮、玛咖芥子油苷能够抑制糖异生代谢。玛咖黄酮、芥子油苷能够直接激活AMPK蛋白,使其磷酸化形成p-AMPK。磷酸化的P-AMPK,可以磷酸化TORC2蛋白,使其形成p-TORC2。而磷酸化的P-TORC2不能进入细胞核,导致p-CREB蛋白的减少,最终使得糖异生代谢关键基因PEPCK和G6Pase转录减少,进而引起PEPCK和G6Pase两种关键蛋白酶的表达减少,最终导致糖异生代谢的抑制。(4)玛咖能改善3T3-L1脂肪细胞胰岛素抵抗状态成功诱导建立了 3T3-L1胰岛素抵抗模型,研究发现玛咖黄酮、玛咖芥子油苷能增加模型细胞的葡萄糖摄入量。玛咖黄酮能够显著增加PPAR-γ含量,但是芥子油苷对PPAR-γ含量没有显著影响。同时发现,玛咖芥子油苷、玛咖黄酮都能增加模型组中GLUT-4葡萄糖转运子的数量。(5)玛咖改善SD大鼠2型糖尿病状态通过STZ结合高糖高脂饲养,成功将SD大鼠诱导为糖尿病模型。实验中玛咖黄酮、玛咖芥子油苷分别设立三个剂量组,通过灌胃五周,玛咖总黄酮、芥子油苷都能够降低SD糖尿病大鼠的血糖含量;同时二者在高剂量时能够降低糖化血红蛋白含量。通过组织病理切片,看到喂养五周后,二者都能够使SD糖尿病大鼠中肝脏的炎症下降。玛咖黄酮、芥子油苷增加胰岛素信号通路中P-AMPK含量,此外,玛咖总黄酮还能够提高GLUT-2转运子数量。
[Abstract]:Lepidium meyeniiae, native to the Andes Mountains of South America, has been successfully planted in Yunnan, Sichuan and Xinjiang since 2007, with an area of more than 200000 mu. People with type 2 diabetes who ate maca showed a drop in blood sugar, but it was unclear why Maca could. In this paper, in vitro, cell and animal experiments were used to systematically study the hypoglycemic active substance and its hypoglycemic mechanism in Maca, so as to lay a foundation for the application of Maca in the development of hypoglycemic products. The main results were as follows: (1) the rhinoside was isolated and purified. The flavonoids were extracted by ultrasonic cycle and purified by D101 macroporous resin and IRA-67 ion exchange resin. The purity of margarine was over 78.3%. Through the purification of macroporous resin AB-8 and polyamide, a purity of 89.2% of Maca total flavone was obtained. The inhibitory effect of glucoside on 伪 -glucosidase activity was obvious, and glucoside inhibited 伪 -glucosidase activity. The IC50 of Maca flavonoids was 0.41 mg / mL, which was a mixture of competitive inhibition and non-competitive inhibition, while the IC50 of macaroside was 0.73 mg / mL, which was a competitive inhibition. 伪 -glucosidase in Caco-2 cells was also inhibited significantly. The IC50 of maca total flavonoids was 0.21 mg / mL, and the IC50 of Maca mustard oil was 0.33 mg / m 路L ~ (3) Maca could improve the glycometabolism of insulin resistance model of Hep-G2 hepatocytes by using Hep-G2 cell insulin resistance model. Magna mustard oil glucoside can inhibit glycometabolism. Maqa flavonoids and mustard oil glucoside can directly activate AMPK protein and phosphorylate it to form p-AMPK. Phosphorylated P-AMPK can phosphorylate TORC2 protein to form p-TORC2. However, phosphorylated P-TORC2 could not enter the nucleus, resulting in the decrease of p-CREB protein, which resulted in the reduction of the transcription of the key genes of glycometabolism, PEPCK and G6Pase, and the decrease of the expression of PEPCK and G6Pase. Finally, the inhibition of glycometabolism. 4) Maca can improve the insulin resistance of 3T3-L1 adipocytes. The 3T3-L1 insulin resistance model was established successfully. It was found that maca flavonoids and maca mustard oil glucoside could increase the glucose intake of the model cells. Maca flavonoids could significantly increase the content of PPAR- 纬, but mustard oil glucoside had no significant effect on the content of PPAR- 纬. It was also found that macamustard oil glucoside and maca flavone could increase the number of GLUT-4 glucose transporters in the model group. Maca could improve the state of type 2 diabetes in SD rats. SD rats were successfully induced into diabetic model by STZ combined with high glucose and high fat. In the experiment, Maca flavonoids and macarosin were divided into three dosage groups. After five weeks of gavage, the total flavone of maca and the glucoside could all reduce the blood sugar content of SD diabetic rats. At the same time, both can reduce the content of glycosylated hemoglobin at high dose. Histopathological sections showed that both of them could decrease liver inflammation in SD diabetic rats after five weeks of feeding. The content of P-AMPK in insulin signaling pathway was increased by maqa flavone, and the amount of GLUT-2 transporter was also increased by total flavone of maca.
【学位授予单位】：中国科学院大学(中国科学院过程工程研究所)
【学位级别】：博士
【学位授予年份】：2017
【分类号】：R285

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