麦胚凝集素修饰的胰岛素脂质体对小鼠口服吸收的促进作用  

Enhancing effect of liposomes composed of different lipids or modified by wheat germ agglutinin on insulin oral absorption in mice

作　　者：张娜[1] 平其能[1] 徐文方[2] 

机构地区：[1]中国药科大学,江苏南京210009 [2]山东大学,山东济南250012

出　　处：《中国药学杂志》2004年第4期273-275,共3页Chinese Pharmaceutical Journal

基　　金：国家自然科学基金资助重点项目(39930200)

摘　　要：目的 研究不同磷脂组成及麦胚凝集素(WGA)修饰脂质体对正常小鼠口服胰岛素的吸收促进作用。方法 逆相蒸发法制备包裹胰岛素的磷脂酰乙醇胺(PE)脂质体和普通大豆磷脂(主要成分为磷脂酰胆碱,PC)脂质体。将WGA与PE结合物(WGA-PE)分别掺入上述两种磷脂制备的胰岛素脂质体中制成修饰脂质体。正常小鼠按胰岛素剂量每只7 u分别灌胃给予修饰PE脂质体或PC脂质体,未修饰的PE脂质体或PC脂质体,用葡萄糖酶试剂盒测定小鼠血糖。比较不同WGA-PE掺入浓度的影响。结果 WGA修饰PE脂质体、修饰PC脂质体和未修饰PE脂质体口服后4 h血糖分别降至初始水平的(61.10±16.22)％,(64.72±22.90)％和(86.50±22.40)％,8 h降至(48.52±18.36)％,(46.36±15.12)％和(44.40±28.87)％,12 h为(63.65±16.40)％,(35.9±17.75)％和(72.85±24.08)％。PC脂质体几乎没有降糖作用,与生理盐水对照组相当。低浓度WGA修饰脂质体也表现了降糖作用。结论 磷脂类型对脂质体的促进作用有明显影响,PE的促进作用明显强于PC,可能与PE在胃肠道通过氨基磷脂移入酶的快速移入作用有关。但WGA修饰脂质体中,改进胰岛素吸收的程度相近,表明在修饰脂质体中以WGA的特异性结合为主导作用而与磷脂的种类关系不大。OBJECTIVE: To investigate the enhancing effect of liposomes on insulin absorption through GI tract in mice, which were composed of phosphatidylethanolamine (PE) or commercial soybean phospholipids (mainly containing phosphatidylcholine, PC) or wheat germ agglutinin (WGA) modified PE or PC. METHODS: Insulin liposomes were prepared by reverse-phase evaporation method. WGA modified liposomes were obtained by simply incorporating WGA-PE into the liposomes. After the liposomes were orally applied to each mice at insulin dose of 7 u, the hypoglycemic effect was evaluated according to the blood glucose level. The influence of different amount of WGA-PE on the hypoglycemic action were investigated. RESULTS: The blood glucose levels of the mice given WGA modified PE liposomes, WGA modified PC liposomes and PE liposomes reduced to (61.10 ± 16.22)%, (64.72 ± 22.90)% and (86.50 ± 22.40)% of the initial values at 4 h, (48.52 ± 18.36)%, (46.36 ± 15.12)% and (44.40 ± 28.87)% at 8 h, (63.65 ± 16.40)%, (35.9 ± 17.75)% and (72.85 ± 24.08)% at 12 h respectively. The effect was also found even at lower WGA-PE concentration. PC liposome and saline as control had no positive effects. CONCLUSION: The hypoglycemic effect of insulin may be altered by the lipid types. The effect of PE liposomes probably can be attributed to the flippase on GI cell membrane which can quickly transfer PE into cells. However, WGA modified PC liposome and PE liposome had similar hypoglycemic effects. It suggested the absorption improvement was mainly dependent on the specific combination of WGA to GI cells.

关 键 词：麦胚凝集素 修饰 胰岛素 脂质体 小鼠 口服 促进作用 胃肠吸收 

分 类 号：R969.1[医药卫生—药理学]