肠腔短链脂肪酸与肠切除术后肠道适应性

Luminal short-chain fatty acids and postresection intestinal adaptation.

作者信息

Thompson J S, Quigley E M, Palmer J M, West W W, Adrian T E

机构信息

Surgical Service, Omaha Veterans Administration Medical Center, Nebraska, USA.

出版信息

JPEN J Parenter Enteral Nutr. 1996 Sep-Oct;20(5):338-43. doi: 10.1177/0148607196020005338.

DOI:10.1177/0148607196020005338

PMID:8887902

Abstract

BACKGROUND

Short-chain fatty acids (SCFAs) reportedly have a trophic effect on the small intestine. However, it is unclear if this is a local or primarily systemic effect. Loss of the ileocolonic junction (ICJ) may result in increased SCFAs and bacteria in the small intestine from colonic reflux. Our aim was to evaluate the effect of bypass of the ICJ on intestinal SCFA content and postresection adaptation.

METHODS

Thirty dogs were studied: transection control (TC, n = 10), distal resection of 50% intestine (DR, n = 10), and distal resection with bypass of ICJ (DRBP, n = 10). Animals were killed at 4 and 12 weeks. Luminal SCFAs and bacteria and adaptation of the small intestine were evaluated.

RESULTS

Caloric intake was significantly less in the two resected groups (67 +/- 3 DR and 63 +/- 3, DRBP vs 78 +/- 5 kcal/kg/d TC, p < .05). Body weight and albumin levels were decreased at 12 weeks but were similar between the resected groups (81% +/- 3% and 74% +/- 6% initial and 1.9 +/- 0.1 and 2.1 +/- 0.2 g/dL, DR and DRBP, respectively). Steatorrhea was present for 12 weeks after resection and was greater after DRBP (14.2% +/- 3.8% vs 8.6% +/- 1.9% at 4 weeks and 13.6% +/- 2.5% vs 6.7% +/- 0.6% at 12 weeks, p < .05). Bypassed animals had elevated intraluminal SCFA content (3126 +/- 1094 vs 1791 +/- 538 DR and 1600 +/- 446 micrograms/mL TC, p < .05) and anaerobic bacterial counts (100% vs 50% and 44%, respectively). Tissue inflammation and myeloperoxidase activity were similar. Small intestinal length (174 +/- 10 and 180 +/- 10 cm) and circumference (5.2 +/- 0.4 and 5.2 +/- 0.3 cm) increased to a similar extent in both resected groups at 12 weeks. Thickness of mucosa (1939 +/- 162 vs 1662 +/- 162 microns) and muscle (865 +/- 45 vs 978 +/- 79 microns) layers were similar after DR and DRBP.

CONCLUSION

(1) Bypass of the ICJ after distal resection results in increased growth of anaerobic bacteria and luminal SCFA and is associated with more marked steatorrhea. (2) Bypass of the ICJ does not influence structural adaptation of the small intestine. (3) These findings do not support a local trophic effect for SCFA.

摘要

背景

据报道，短链脂肪酸（SCFAs）对小肠具有营养作用。然而，尚不清楚这是局部作用还是主要为全身作用。回结肠交界（ICJ）的缺失可能导致结肠反流使小肠内SCFAs和细菌增加。我们的目的是评估ICJ旷置对肠道SCFA含量及切除术后适应性的影响。

方法

对30只犬进行研究：横断对照（TC，n = 10）、50%肠段远端切除（DR，n = 10）以及远端切除并ICJ旷置（DRBP，n = 10）。在4周和12周时处死动物。评估肠腔SCFAs、细菌及小肠适应性。

结果

两个切除组的热量摄入显著减少（DR组为67±3，DRBP组为63±3，而TC组为78±5 kcal/kg/d，p <.05）。12周时体重和白蛋白水平降低，但切除组之间相似（DR组和DRBP组初始体重分别为81%±3%和74%±6%，白蛋白水平分别为1.9±0.1和2.1±0.2 g/dL）。切除术后脂肪泻持续12周，DRBP组更严重（4周时分别为14.2%±3.8%和8.6%±1.9%，12周时分别为13.6%±2.5%和6.7%±0.6%，p <.05）。ICJ旷置的动物肠腔内SCFA含量升高（DRBP组为3126±1094，DR组为1791±538，TC组为1600±446微克/毫升，p <.05），厌氧菌计数也升高（分别为100%、50%和44%）。组织炎症和髓过氧化物酶活性相似。12周时，两个切除组的小肠长度（分别为174±10和180±10厘米）和周长（分别为5.2±0.4和5.2±0.3厘米）增加程度相似。DR组和DRBP组术后黏膜厚度（分别为1939±162和1662±162微米）和肌层厚度（分别为865±45和978±79微米）相似。