Roux-en-Y胃旁路术诱导2型糖尿病大鼠血清脂多糖及盲肠菌群的变化

Changes of serum lipopolysaccharide and cecal flora in type 2 diabetic rats induced by Roux - en - Y gastric bypass

目的观察Roux-en-Y胃旁路术（RYGB）对2型糖尿病大鼠血清脂多糖（LPS）及盲肠菌群的影响。方法40只健康雄性Sprague-Dawley（SD）大鼠，从中随机挑取10只喂基础饲料作为正常对照组（NC组）；另外30只复制2型糖尿病模型后，随机分为糖尿病手术组（DO组）、糖尿病对照组（DC组）、糖尿病假手术组（Ds组）。从各组中随机抽取8只，其余大鼠备用。DO组施行RYGB手术。术前及术后第1、2、4、8、12周分别测各组空腹血糖（FPG）、空腹胰岛素（Fins）水平；术前及术后4、8、12周分别测外周血脂多糖（LPS）水平；术后12周留取盲肠内容物，进行盲肠菌群结构及相对丰度比较。结果DO组：术后第2周和第4周FPG分别由术前的（9．10±0．88）mmol／L降至（5．70±0．91）mmol／L和（5．80±0．83）wand／L（P=0．000），至术后第8、12周分别降至（6．04±0．91）mmol／L和（5．89±1．09）mmol／L（P=0.000）；Fins自术后第4周开始下降，至术后8周和12周分别降至（6．36±0．73）mU／L（P=0．030）和（6．34±0．63）mU／L（P=0．027）；术后第4周血清LPS由术前的（44．35±2．41）ng／L降至（38．42±2．90）ng／L（P=0．000），术后8周和12周分别降至（32．32±1．45）ng／L和（32．19±1．24）ng／L（P=0．000）。术后12周通过IlluminaHiseq测序平台对2型糖尿病大鼠盲肠内容物的16SrRNA的V4区测序分析，DO组新增的双歧杆菌，相对丰度为（1．59±0．29）％（P=0．011）。结论RYGB术后的降糖作用可能与LPS水平的改善及盲肠菌群结构的调节有关。

Objective To observe the effect of Roux -en -Y gastric bypass （RYGB） on serum lipopolysaccharide （LPS） and cecal flora in type 2 diabetic rats. Methods A total of 10 Sprague - Daw- Icy （SD） male rats were randomly selected and fed basic diet as normal control group （NC group）, and another 30 rats were randomly divided into diabetes surgery group （ DO group） , diabetes control group （ DC group ） and diabetes sham operation group （DS group）. 8 rats were randomly selected from each group and the rest rats were spare. The DO group underwent RYGB surgery. Fasting blood glucose （FPG） and fasting insulin （Fins） levels were measured before and 1st, 2nd, 4th, 8th, 12th week after surgery; Peripheral blood LPS levels were measured before surgery and at 4, 8, 12 weeks after surgery; The cecal contents were taken 12 weeks after surgery to compare the structure and relative abundance of cecal flora. Results DO group： FPG decreased from （9.10±0.88） mmol/L to （5.70±0.91） mmol/L and （5.80 ±0. 83） mmoL/L （ P = 0. 000 ） at 2 and 4 weeks postoperatively, and to （ 6. 04 ± 0, 91 ） mmol/L and （5.89 ± 1.09） mmoL/L at 8 and 12 weeks postoperatively （P =0. 000） ; Fins began to decline 4 weeks ＇after surgery and decreased to （6. 36 ±. 73） mU/L（P =0. 030） and （6. 34 ±-0. 63） mU/L （P =0. 027） at 8 and 12 weeks after operation. Serum LPS decreased from （ 44. 35 ±2. 41 ） ng/L to （ 38. 42 ±2.90） ng/L （P =0. 000） 4 weeks after operation, and decreased to （32. 32 ± 1.45） ng/L and （32. 19 ± 1.24） ng/L （P =0. 000） at 8 and 12 weeks after operation. The V4 region of the 16S rRNA of cecal con- tents in type 2 diabetic rats was sequenced by Illunfina Hiseq sequencing platform 12 weeks after surgery. The relative abundance of Bifidobacterium in the DO group was （ 1.59 ± 0. 29 ） % （ P = 0. 011 ）. Conclusion Hypoglycemic effects after RYGB may be associated with improvement of LPS levels and regulation of cecal flora structure.