Adiponectin plays a vital role in the regulation of insulin sensitivity and glucose homeostasis,and is closely related to insulin resistance.Visfatin can interact with the insulin receptor,playing a para-insulin or anti-insulin effect,so as to reduces blood glucose.Its quantitative change of volume also has tight correlation with insulin resistance.3T3-L1 pre-adipocytes were cultivated and differentiated in adipogenic cocktail containing isobutyl-l-methyl xanthine (IBMX),dexamethasone (DEX) and insulin; the morphology and differentiation of adipocytes were identified by oil red O staining; High glucose/ insulin acted on adipocytes to establish insulin resistance cells model; glucose content in culture medium was measured by glucose oxidase method and glucose consumption was calculated to confirm the establishment of insulin resistance model.The changes of adiponectin and visfatin protein expressions before and after drug action were detected by Western blot to study the mechanism of Neu-P11's effect on improving high glucose/ insulin and causing 3T3-L1 adipose cells' insulin resistance; the combined effects of melatonin receptor antagonist Luzindole and Neu-P11 on glucose uptake and the expressions of adiponectin and visfatin protein were probed.The research indicates that 24 h after the action of high glucose/ insulin on differentiated and matured adipocytes,the glucose assumption decreased dramatically compared with that of the cells of controlled group,and insulin sensitivity also decreased thereupon.After treated by melatonin and Neu-P11,the glucose consumption of the cells in insulin resistance group increased obviously,compared with those in IR group,and the insulin sensitivity also increased accordingly.The expression of adiponectin protein increased dramatically compared with IR group,and the change had statistical significance.The change of the expression of visfatin protein was not obvious,and had no statistical significance compared with IR group.After the respective combined effects of the combination of Mel and melatonin receptor antagonist Luzindole and that of Neu-P11 and Luzindole on cells,the expression level of adiponectin protein experienced dramatic decline compared with the Mel and Neu-P11 group,and the differences had statistical significance; the differences were not obvious compared with IR group and had no statistical significance.Therefore,both melatonin and Neu-P11 can improve the insulin resistance and insulin sensitivity of adipocytes,increase glucose consumption and up-regulate the expression of adiponectin protein.They have no clear effects on visfatin protein.Melatonin and Neu-P11 may be able to play the above mentioned effects with their respective combination with melatonin receptor 2 (Mel 1b); Melatonin receptor antagonist Luzindole can block the combination of melatonin and Neu-P11 with melatonin receptor 2 (Mel 1b) respectively; Both Neu-P11 and adiponectin have brilliant development prospect in treating diabetes.%脂联素(adiponectin)在调节胰岛素敏感性和葡萄糖的内稳态方面发挥着至关重要的作用,与胰岛素抵抗密切相关;内脏脂肪素(visfatin)可与胰岛素受体相互作用,发挥类胰岛素或抗胰岛素样作用,从而降低血糖,其量的变化与胰岛素抵抗的发生也有着紧密的联系.通过“鸡尾酒”法培养并分化3T3-L1前脂肪细胞,油红O染色鉴定脂肪细胞的形态和分化情况,高糖高胰岛素作用于脂肪细胞,建立胰岛素抵抗细胞模型;葡萄糖氧化酶法测定培养基中的糖含量,计算糖消耗量,验证胰岛素抵抗模型的建立.葡萄糖氧化酶法检测药物作用前后培养基中的糖含量,计算糖消耗量;Western-blot检测药物作用前后脂联素和内脏脂肪素表达的变化,来研究Neu-P11改善高糖高胰岛素引起3T3-L1脂肪细胞发生胰岛素抵抗的机制,以及葡萄糖摄取和脂联素及内脏脂肪素的变化;探讨褪黑素受体拮抗剂Luzindole与Neu-P11联合作用后,对葡萄糖摄取及脂联素和内脏脂肪素表达的影响.结果表明,高糖高胰岛素作用于分化成熟的脂肪细胞24 h后,糖消耗量与正常对照组细胞相比明显降低,其胰岛素敏感性也随之下降;胰岛素抵抗组细胞用褪黑素和Neu-P 11处理后,糖消耗量与未处理组相比明显升高,胰岛素敏感性也随之上升;脂联素表达明显增高,与未处理组相比,差异有统计学意义;内脏脂肪素表达变化不明显,与未处理组相比,差异没有统计学意义.褪黑素、Neu-P11分别与褪黑素受体拮抗剂Luzindole联合作用于细胞后,细胞的脂联素表达水平与未加拮抗剂Luzindole的褪黑素、Neu-P11组相比明显下降,差异具有统计学意义,与末处理组相比,没有明显变化,差异没有统计学意义.因此,褪黑素和Neu-P11都可提高胰岛素抵抗脂肪细胞的胰岛素敏感性,增加糖消耗量,使脂联素表达上调,而对内脏脂肪素表达没有明显影响;褪黑素和Neu-P11可能是通过与褪黑素受体2 (Mel1b)结合发挥上述作用的;褪黑素受体拮抗剂Luzindole能够阻断褪黑素和Neu-P11与褪黑素受体2(Mel1b)的结合.以上结果说明,Neu-P11和脂联素在治疗糖尿病方面都有着非常大的发展前景.
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