Yassin K, Huyen V T T, Hoa K N, Ostenson C G
Depatment of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden;
Int J Biomed Sci. 2011 Jun;7(2):131-6.
The aim of the study was to explore the effect of Gynostemma pentaphyllum (GP) extract on hepatic glucose output (HGO) in spontaneously type 2 diabetic Goto-Kakizaki (GK) rats treated orally with GP or placebo extract 1600 mg/kg daily, during three days or three weeks. The three-week treatment of GP, but not three-day treatment, significantly reduced plasma glucose (PG) levels from 9.8 ± 0.6 to 6.8 ± 0.4 mmol/L (p=0.027) in GK rats, whereas PG levels were not significantly decreased in the placebo rats. Glucose tolerance assessed by an intra-peritoneal glucose tolerance test was significantly improved in GP treated compared to placebo treated group (areas under the glucose curves, AUCs, from 0 to 120 min were 1150 ± 200 vs. 1761 ± 87 mmol/L; p=0.013). The glucose response in an intra-peritoneal pyruvate tolerance test from minute 15 to minute 120, the AUC (15-120) was significantly lower in the GP group (415.5 ± 68.0 vs. 641.5 ± 41.8 mmol/L; p<0.05). In liver perfusions, the AUCs for HGO during 18 min (0-18 min) were significantly decreased in GP treated rats compared with control rats (302.8 ± 36.5 vs. 423.5 ± 44.7 μmol, p<0.05). The three-week GP treatment significantly reduced the hepatic glycogen content, but not glycogen synthase activity compared to placebo group (p<0.007). In conclusion, three-week treatment of GP extract exerted anti-diabetic effect in GK rats, reducing plasma glucose levels and HGO, suggesting that GP improves the hepatic insulin sensitivity by suppressing gluconeogenesis.
本研究旨在探讨绞股蓝（GP）提取物对自发性2型糖尿病Goto-Kakizaki（GK）大鼠肝葡萄糖输出（HGO）的影响。将GK大鼠每日口服1600 mg/kg的GP提取物或安慰剂提取物，持续三天或三周。三周的GP治疗（而非三天治疗）显著降低了GK大鼠的血糖（PG）水平，从9.8±0.6降至6.8±0.4 mmol/L（p = 0.027），而安慰剂组大鼠的PG水平未显著降低。与安慰剂治疗组相比，经腹腔葡萄糖耐量试验评估，GP治疗组的葡萄糖耐量显著改善（0至120分钟的葡萄糖曲线下面积，AUCs，分别为1150±200与1761±87 mmol/L；p = 0.013）。在腹腔丙酮酸耐量试验中，从第15分钟到第120分钟的葡萄糖反应，GP组的AUC（15 - 120）显著更低（415.5±68.0与641.5±41.8 mmol/L；p < 0.05）。在肝脏灌注实验中，与对照大鼠相比，GP治疗组大鼠在18分钟（0 - 18分钟）内HGO的AUC显著降低（302.8±36.5与423.5±44.7 μmol，p < 0.05）。与安慰剂组相比，三周的GP治疗显著降低了肝糖原含量，但糖原合酶活性未降低（p < 0.007）。总之，三周的GP提取物治疗对GK大鼠发挥了抗糖尿病作用，降低了血糖水平和HGO，表明GP通过抑制糖异生改善了肝脏胰岛素敏感性。
