双歧杆菌黏附素对大鼠肠缺血再灌注损伤后肠道菌群和细菌易位的影响

Abstract

目的: 观察双歧杆菌黏附素对大鼠肠缺血再灌注损伤(intestinal ischemia reperfusion injury, I/R)后肠道菌群和细菌易位的影响.

方法: SD大鼠72只随机分为假手术组(对照组, 24只)、I/R模型组(24只)和黏附素实验组(24只). 建模成功后6 h及1、4、7 d, 各组分别取6只大鼠剖杀, 观察肠道菌群和细菌易位的变化情况, 并检测各时间点血浆内毒素水平.

结果: I/R组各时点大鼠粪便中肠球菌(6.63 lgN/g±1.06 lgN/g vs 5.26 lgN/g±1.08 lgN/g, 9.44 lgN/g±1.37 lgN/g vs 5.30 lgN/g±1.12 lgN/g, 8.56 lgN/g±1.35 lgN/g vs 4.99 lgN/g±0.96 lgN/g, 8.23 lgN/g±1.01 lgN/g vs 5.18 lgN/g±1.03 lgN/g, P<0.05)和肠杆菌(7.86 lgN/g±1.17 lgN/g vs 6.39 lgN/g±0.85 lgN/g, 9.49 lgN/g±1.23 lgN/g vs 6.64 lgN/g±1.44 lgN/g, 8.76 lgN/g±0.86 lgN/g vs 6.52 lgN/g±1.13 lgN/g, 8.89 lgN/g±1.09 lgN/g vs 6.71 lgN/g±0.98 lgN/g, P<0.05)数量较对照组均明显升高, 产气荚膜梭菌数量在1 d(6.47 lgN/g±1.43 lgN/g vs 4.51 lgN/g±1.22 lgN/g, P<0.05)、4 d(6.70 lgN/g±1.16 lgN/g vs 4.71 lgN/g±0.89 lgN/g, P<0.05)、7 d(6.55 lgN/g±1.29 lgN/g vs 4.46 lgN/g±0.79 lgN/g, P<0.05)时较对照组均明显升高, 双歧杆菌(6.13 lgN/g±1.28 lgN/g vs 9.02 lgN/g±1.10 lgN/g, 5.59 lgN/g±1.22 lgN/g vs 8.66 lgN/g±0.99 lgN/g, P<0.05)、乳杆菌数量(6.07 lgN/g±1.09 lgN/g vs 9.08 lgN/g±1.04 lgN/g, 5.35 lgN/g±1.26 lgN/g vs 8.89 lgN/g±0.97 lgN/g, P<0.05)在4、7 d时较对照组明显降低; 实验组粪便中肠球菌(6.37 lgN/g±1.04 lgN/g vs 8.56 lgN/g±1.35 lgN/g, 5.42 lgN/g±0.92 lgN/g vs 8.23 lgN/g±1.01 lgN/g, P<0.05)和肠杆菌数量(7.55 lgN/g±1.03 lgN/g vs 8.76 lgN/g±0.86 lgN/g, 7.16 lgN/g±0.86 lgN/g vs 8.89 lgN/g±1.09 lgN/g, P<0.05)在4、7 d时均明显低于I/R组, 在1、4、7 d时粪便中产气荚膜梭菌数量虽仍高于对照组(5.95 lgN/g±1.24 lgN/g vs 4.51 lgN/g±1.22 lgN/g, 6.08 lgN/g±1.07 lgN/g vs 4.71 lgN/g±0.89 lgN/g, 5.87 lgN/g±0.82 lgN/g vs 4.46 lgN/g±0.79 lgN/g, P<0.05), 但较I/R组已有所下降, 各时点双歧杆菌(8.56 lgN/g±0.85 lgN/g vs 8.45 lgN/g±0.86 lgN/g, 7.89 lgN/g±1.47 lgN/g vs 8.78 lgN/g±1.06 lgN/g, 8.67 lgN/g±1.13 lgN/g vs 9.02 lgN/g±1.10 lgN/g, 8.75 lgN/g±0.96 lgN/g vs 8.66 lgN/g±0.99 lgN/g, P>0.05)和乳杆菌数量(9.16 lgN/g±0.94 lgN/g vs 8.91 lgN/g±1.06 lgN/g, 8.56 lgN/g±1.21 lgN/g vs 9.11 lgN/g±1.13 lgN/g, 9.16 lgN/g±1.08 lgN/g vs 9.08 lgN/g±1.04 lgN/g, 9.01 lgN/g±0.95 lgN/g vs 8.89 lgN/g±0.97 lgN/g, P>0.05)则较对照组均无显著变化; I/R组各时点血浆内毒素水平(1.43 EU/mL±0.32 EU/mL vs 0.21 EU/mL±0.18 EU/mL, 1.84 EU/mL±0.24 EU/mL vs 0.30 EU/mL±0.23 EU/mL, 1.69 EU/mL±0.35 EU/mL vs 0.26 EU/mL±0.21 EU/mL, 1.73 EU/mL±0.31 EU/mL vs 0.28 EU/mL±0.19 EU/mL, P<0.05)及肝(50% vs 0, 66.67% vs 16.67%, 83.33% vs 0, 83.33% vs 0, P<0.05)、脾(33.33% vs 0, 50% vs 0, 66.67% vs 0, 66.67% vs 0, P<0.05)和肠系膜淋巴结(66.67% vs 0, 83.33% vs 0, 100% vs 16.67%, 100% vs 0, P<0.05)细菌易位率均明显高于对照组, 实验组各时点血浆内毒素水平(0.57 EU/mL±0.23 EU/mL vs 1.43 EU/mL±0.32 EU/mL, 0.71 EU/mL±0.16 EU/mL vs 1.84 EU/mL±0.24 EU/mL, 0.41 EU/mL±0.22 EU/mL vs 1.69 EU/mL±0.35 EU/mL, 0.35 EU/mL±0.12 EU/mL vs 1.73 EU/mL±0.31 EU/mL, P<0.05)及肝(16.67% vs 50%, 33.33% vs 66.67%, 50% vs 83.33%, 33.33% vs 83.33%, P<0.05)、脾(0 vs 33.33%, 16.67% vs 50%, 33.33% vs 66.67%, 33.33% vs 66.67%, P<0.05)和肠系膜淋巴结(50% vs 66.67%, 50% vs 83.33%, 50% vs 100%, 33.33% vs 100%, P<0.05)细菌易位率均明显低于I/R组.

结论: 双歧杆菌分泌型黏附素可改善I/R后肠道菌群失衡, 减少肠道细菌易位及内毒素血症的发生, 保护肠黏膜屏障功能.

Keywords: 黏附素; 双歧杆菌; 肠缺血再灌注损伤; 肠道菌群; 细菌易位; 内毒素血症

核心提示: 本文观察了双歧杆菌黏附素对大鼠肠道缺血再灌注损伤(intestine ischemia/reperfusion injury, I/R)后肠道菌群和细菌易位的影响, 发现双歧杆菌分泌型黏附素可改善I/R后肠道菌群失衡, 减少肠道细菌易位及内毒素血症的发生. 作为一种菌体成分, 黏附素保存、运输方便, 又避免了益生菌的其他一些不足之处, 因此为肠屏障功能障碍的防护提供了一条崭新的临床思路.