Skip Navigation LinksHome > March-April 2013 - Volume 19 - Issue 4 > BTB and CNC Homolog 1 (Bach1) Deficiency Ameliorates TNBS Co...
Inflammatory Bowel Diseases:
doi: 10.1097/MIB.0b013e3182802968
Original Basic Science Articles

BTB and CNC Homolog 1 (Bach1) Deficiency Ameliorates TNBS Colitis in Mice: Role of M2 Macrophages and Heme Oxygenase-1

Harusato, Akihito MD, PhD*; Naito, Yuji MD, PhD*; Takagi, Tomohisa MD, PhD*; Uchiyama, Kazuhiko MD, PhD*; Mizushima, Katsura BS*; Hirai, Yasuko BS*; Higashimura, Yasuki PhD*; Katada, Kazuhiro MD, PhD*; Handa, Osamu MD, PhD*; Ishikawa, Takeshi MD, PhD*; Yagi, Nobuaki MD, PhD*; Kokura, Satoshi MD, PhD*; Ichikawa, Hiroshi MD, PhD; Muto, Akihiko MD, PhD; Igarashi, Kazuhiko MD, PhD; Yoshikawa, Toshikazu MD, PhD*

Collapse Box

Abstract

Background: BTB and CNC homolog 1 (Bach1) is a transcriptional repressor of heme oxygenase-1 (HO-1), which plays an important role in the protection of cells and tissues against acute and chronic inflammation. However, the role of Bach1 in the gastrointestinal mucosal defense system remains little understood. HO-1 supports the suppression of experimental colitis and localizes mainly in macrophages in colonic mucosa. This study was undertaken to elucidate the Bach1/HO-1 system's effects on the pathogenesis of experimental colitis.

Methods: This study used C57BL/6 (wild-type) and homozygous Bach1-deficient C57BL/6 mice in which colonic damage was induced by the administration of an enema of 2,4,6-trinitrobenzene sulfonic acid (TNBS). Subsequently, they were evaluated macroscopically, histologically, and biochemically. Peritoneal macrophages from the respective mice were isolated and analyzed. Then, wild-type mice were injected with peritoneal macrophages from the respective mice. Acute colitis was induced similarly.

Results: TNBS-induced colitis was inhibited in Bach1-deficient mice. TNBS administration increased the expression of HO-1 messenger RNA and protein in colonic mucosa in Bach1-deficient mice. The expression of HO-1 mainly localized in F4/80-immunopositive and CD11b-immunopositive macrophages. Isolated peritoneal macrophages from Bach1-deficient mice highly expressed HO-1 and also manifested M2 macrophage markers, such as Arginase-1, Fizz-1, Ym1, and MRC1. Furthermore, TNBS-induced colitis was inhibited by the transfer of Bach1-deficient macrophages into wild-type mice.

Conclusions: Deficiency of Bach1 ameliorated TNBS-induced colitis. Bach1-deficient macrophages played a key role in protection against colitis. Targeting of this mechanism is applicable to cell therapy for human inflammatory bowel disease.

© Crohn's & Colitis Foundation of America, Inc.

You currently do not have access to this article.

You may need to:

Note: If your society membership provides for full-access to this article, you may need to login on your society’s web site first.

Login

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.