Clinical Research
Copyright ©2005 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 14, 2005; 11(10): 1535-1539
Published online Mar 14, 2005. doi: 10.3748/wjg.v11.i10.1535
Hypoxia-inducible factor 1 alpha and vascular endothelial growth factor overexpression in ischemic colitis
Tomoyuki Okuda, Takeshi Azuma, Masahiro Ohtani, Ryuho Masaki, Yoshiyuki Ito, Yukinao Yamazaki, Shigeji Ito, Masaru Kuriyama
Tomoyuki Okuda, Takeshi Azuma, Yoshiyuki Ito, Masaru Kuriyama, Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Matsuoka-cho, Fukui 9101193, Japan
Masahiro Ohtani, Yukinao Yamazaki, Department of Endoscopic Medicine, Faculty of Medical Sciences, University of Fukui, Matsuoka-cho, Fukui 9101193, Japan
Ryuho Masaki, Shigeji Ito, Department of Internal Medicine, Tannan Regional Medical Center, Sabae, Fukui 9168515, Japan
Author contributions: All authors contributed equally to the work.
Correspondence to: Takeshi Azuma, M.D., Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Matsuoka-cho, Yoshida-gun, Fukui 9101193, Japan. azuma@fmsrsa.fukui-med.ac.jp
Telephone: +81-776-61-8351 Fax: +81-776-61-8110
Received: August 24, 2004
Revised: August 26, 2004
Accepted: December 1, 2004
Published online: March 14, 2005
Abstract

AIM: To examine the etiology and pathophysiology in human ischemic colitis from the viewpoint of ischemic factors such as hypoxia-inducible factor 1 alpha (HIF-1 alpha and vascular endothelial growth factor (VEGF).

METHODS: Thirteen patients with ischemic colitis and 21 normal controls underwent colonoscopy. The follow-up colonoscopy was performed in 8 patients at 7 to 10 d after the occurrence of ischemic colitis. Biopsy samples were subjected to real-time RT-PCR and immunohistochemistry to detect the expression of HIF-1 alpha and VEGF.

RESULTS: HIF-1 alpha and VEGF expression were found in the normal colon tissues by RT-PCR and immunohistochemistry. HIF-1 alpha and VEGF were overexpressed in the lesions of ischemic colitis. Overexpressed HIF-1 alpha and VEGF RNA quickly decreased to the normal level in the scar regions at 7 to 10 d after the occurrence of ischemic colitis.

CONCLUSION: Constant expression of HIF-1 alpha and VEGF in normal human colon tissue suggested that HIF-1 alpha and VEGF play an important role in maintaining tissue integrity. We confirmed the ischemic crisis in ischemic colitis at the molecular level, demonstrating overexpression of HIF-1 alpha and VEGF in ischemic lesions. These ischemic factors may play an important role in the pathophysiology of ischemic colitis.

Keywords: Ischemic colitis; HIF-1 alpha; VEGF