姜黄素对单纯性肥胖大鼠胰岛素抵抗及瘦素抵抗的影响

The study of insulin resistance and leptin resistance on the model of simplicity obesity rats by curcumin

目的探讨姜黄素对单纯性肥胖模型大鼠胰岛素抵抗及瘦素抵抗的影响。方法初断乳雄性SPF级sD大鼠50只，按体重分层后随机分为2组。分别为高脂饲料喂饲组（30只），基础饲料喂饲组（20只）。8周后观察比较体重变化。建模成功后，将肥胖模型大鼠按体重随机分为3组，分别为姜黄素高剂量组（5．00g／kg）、姜黄素低剂量组（1．25g／kg）及肥胖模型对照组。基础饲料喂饲组按体重随机分为2组，分别为姜黄素高剂量对照组（5．00g／妇）、基础对照组。每组各10只，各组动物均自由摄食基础饲料。灌胃给予不同剂量姜黄素4周后，检测体重、脂体比、血糖、胰岛素、瘦素、肿瘤坏死因子的影响及胰腺结构改变。结果给予姜黄素4周后，姜黄素高剂量组大鼠体重[（435．0±37．6）g]和体脂含量[（4．78±1．87）g]低于肥胖模型对照组大鼠体重[（492．3±14．8）g]和体脂含量[（8．94±1．88）g]（t值分别为4．484和4．961，P值均〈0．01）；姜黄素高剂量组大鼠血糖[（4．50±0．09）mmol／L]、胰岛素[（7．43±0．65）mmol／L]、瘦素[（3．40±0．39）mmol／L]及肿瘤坏死因子水平[（2．42±0．19）ng／m1]低于肥胖模型对照组大鼠血糖[（4．94±0．12）mmol／L]、胰岛素[（9．30±0．21）mmol／L]、瘦素[（4．40±O．23）mmol／L]及肿瘤坏死因子水平[（2．86±0．49）ng／m1]，（t值分别为8．297、7．743、6．247、2．368，P值均〈0．05）；且血糖水平与基础对照组[（4．30±0．14）mmol／L]差异无统计学意义（t：0．399，P〉0．05）。超微结构观察显示，给予姜黄素后，胰岛B细胞内含有大量的分泌颗粒，颗粒多呈圆形，颗粒内电子密度较高，颗粒外有较大的空隙。结论姜黄素可通过减轻胰腺组织脂肪沉积，使胰岛素淋巴回流畅通，抑制胰岛细胞的凋亡，而有效缓解肥胖引起的胰岛素抵抗和瘦素抵抗。

Objective To evaluate the insulin and leptin resistance of curcumin on simplicity obesity rats. Methods All 50 SPF grade healthy Sprague-Dawlay male initial weaning rats were used for two groups in stratified sampling by weight： 30 in treated group and 20 in control group. They were assigned to the following treatment for 8 weeks ： the treated group was fed with high-fat food and the control group was fed with normal food. Eight weeks later, adiposity model rats were prepared. Groups： adiposity model rats were divided into 3 groups： model ＋ low curcumin （1.25 g/kg） ,model ＋ high curcumin （5.00 g/kg） and a model group. In addition, there also had a normal control and a control ＋ high curcumin （ 5.00 g/kg） group. Ten rats in every group and all given ground feed. After intragastric administration in different doses of curcumin 4 weeks,the effects and pathological changes were observed by the blood sugar,insulin, leptin and TNF-α,pathology and transmission electron microscope of pancreatic gland. Results Given 4 weeks the different dose of curcumin on the simplicity obesity rats, the significant diminished weight （435. 0 ± 37. 6） g and content of lipocyte （4.78 ±1.87）g as compared with the obesity model control （492. 3 ± 14. 8）g and （8. 94 ± 1.88） g （ t values were 4. 484 and 4. 961 respectively, P 〈 0. O1 ）, level of blood sugar （4. 50 ± 0.09） mmol/L,insulin（7.43 ±0. 65） mmol/L,leptin（3.40 ±0. 39） mmol/L and TNF-α （2.42 ±0. 19） rig/ ml were significantly decreased than those of adiposity model rats （4. 94± 0. 12） mmol/L, （ 9. 30 ± O. 21 ） mmol/L, （4. 40± 0. 23 ） mmol/L and （ 2. 86 ± 0.49 ） ng/ml （ t values were 8. 297,7. 743,6. 247 and 2. 368 respectively, P 〈 0. 05 ）, and there was no significant difference with the control group （4. 30 ± 0. 14 ） mmol/L on the level of blood sugar（ t = 0. 399, P 〉 0. 05 ）. There were a lot of secretory granules with large sphere volume in 13 cells of pancreatic island found by transmission electron microscope, and these secretory granules had a higher electron density than those in non-disposed groups. Conclusion By diminishing the sediment of fat, relaxing the lymphatic return, and refraining the apoptosis of β cells, the curcumin might significantly decrease the level of insulin resistance and leptin resistance caused by the high fat diet.