Original Article
Copyright ©2014 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jun 21, 2014; 20(23): 7442-7451
Published online Jun 21, 2014. doi: 10.3748/wjg.v20.i23.7442
Protective effect of bone marrow mesenchymal stem cells in intestinal barrier permeability after heterotopic intestinal transplantation
Wen Zhang, Zhong-Yang Shen, Hong-Li Song, Yang Yang, Ben-Juan Wu, Nan-Nan Fu, Tao Liu
Wen Zhang, Zhong-Yang Shen, Hong-Li Song, Yang Yang, Ben-Juan Wu, Nan-Nan Fu, Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, China
Tao Liu, Key Laboratory of Emergency Care Medicine of Ministry of Health, Tianjin First Central Hospital, Tianjin 300192, China
Author contributions: Zhang W and Shen ZY contributed equally to this work; Song HL designed the research; Zhang W, Shen ZY and Song HL analyzed and interpreted the data, and wrote the manuscript; Zhang W, Shen ZY, Yang Y, Wu BJ, Fu NN and Liu T performed the research; all authors have read and approved the final manuscript.
Supported by The Natural Science Foundation of China, No. 81270528; the Natural Science Foundation of Tianjin, China, No. 08JCYBJC08400, No. 11JCZDJC27800 and No. 12JCZDJC25200; and the Technology Foundation of Health Bureau of Tianjin, China, No. 2011KY11
Correspondence to: Hong-Li Song, MD, PhD, Professor of Medicine, Department of Organ Transplantation, Tianjin First Central Hospital, No. 24 Fukang Road, Nankai District, Tianjin 300192, China. hlsong26@163.com
Telephone: +86-22-23626928 Fax: +86-22-23626622
Received: January 9, 2014
Revised: March 11, 2014
Accepted: April 21, 2014
Published online: June 21, 2014
Abstract

AIM: To explore the protective effect of bone marrow mesenchymal stem cells (BM MSCs) in the small intestinal mucosal barrier following heterotopic intestinal transplantation (HIT) in a rat model.

METHODS: BM MSCs were isolated from male Lewis rats by density gradient centrifugation, cultured, and analyzed by flow cytometry. The HIT models were divided into a non-rejection group, saline-treated rejection group (via penile vein), and BM MSC–treated group (via penile vein). Intestinal mucosal barrier injury was estimated by diamine oxidase (DAO) and D-lactic acid (D-LA) expression levels. Tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), interleukin-10 (IL-10), and transforming growth factor-β (TGF-β) were detected by enzyme-linked immunosorbent assay. Ultrastructural change of tight junctions (TJs) was observed under transmission electron microscope. Expression levels of the TJ proteins occludin and zona occludens (ZO)-1, affected by the inflammatory factors, were measured using real-time polymerase chain reaction and Western blotting.

RESULTS: The pathological score at each time point after surgery indicated significantly less serious injury in the BM MSCs-treated group than in the rejection group (P < 0.05). In the former, graft levels of DAO and D-LA were reduced, and TNF-α and INF-γ production was inhibited (at day 7: 10.6473 ± 0.0710 vs 17.2128 ± 0.4991, P < 0.05; 545.1506 ± 31.9416 vs 810.2637 ± 25.1175, P < 0.05). IL-10 and TGF-β production was increased greatly (at day 7: 125.7773 ± 4.7719 vs 80.3756 ± 2.5866, P < 0.05; 234.5273 ± 9.3980 vs 545.1506 ± 31.9416, P < 0.05). There was increased expression of occludin and ZO-1 protein (at day 7: 0.2674 ± 0.0128 vs 0.1352 ± 0.0142, P < 0.05; at day 5: 0.7189 ± 0.0289 vs 0.4556 ± 0.0242, P < 0.05) and mRNA (at day 7: 0.3860 ± 0.0254 vs 0.1673 ± 0.0369, P < 0.05; at day 5: 0.5727 ± 0.0419 vs 0.3598 ± 0.0242, P < 0.05).

CONCLUSION: BM MSCs can improve intestinal barrier permeability, repair TJs, and increase occludin and ZO-1 protein expression. With altered cytokine levels, they can protect the intestinal mucosa after transplantation.

Keywords: Bone marrow mesenchymal stem cells, Small intestinal transplantation, Intestinal mucosal barrier, Occludin, Zona occludens-1

Core tip: Rejection and sepsis after small intestinal transplantation (SITx) is a serious and common complication. The small intestinal mucosal barrier plays an important role in the progression of postoperative complications. This study demonstrated that in rats, implantation of recipient-derived bone marrow mesenchymal stem cells decreased intestinal permeability and preserved intestinal mucosal barrier function after SITx via a mechanism linked to the balance between graft inflammatory cytokine levels and increased expression of the intestinal tight junction proteins occludin and zona occludens-1.