Brief Article
Copyright ©2012 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. May 7, 2012; 18(17): 2132-2139
Published online May 7, 2012. doi: 10.3748/wjg.v18.i17.2132
Emodin promoted pancreatic claudin-5 and occludin expression in experimental acute pancreatitis rats
Xian-Ming Xia, Bang-Ku Li, Shi-Mei Xing, Hai-Ling Ruan
Xian-Ming Xia, Shi-Mei Xing, Hai-Ling Ruan, Department of Gastroenterology and Hepatology, the Fourth Affiliated Hospital of Anhui Medical University, Hefei 230022, Anhui Province, China
Bang-Ku Li, Department of Gastroenterology and Hepatology, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, Anhui Province, China
Author contributions: Xia XM and Li BK designed the research; Xia XM, Li BK, Xing SM and Ruan HL performed the experiments; Xing SM analyzed the data; and Xia XM wrote the paper.
Supported by National Natural Science Foundation of China, No. 30500688
Correspondence to: Xian-Ming Xia, Associate Professor, PhD, Department of Gastroenterology and Hepatology, the Fourth Affiliated Hospital of Anhui Medical University, 372 Tunxi Road, Hefei 230022, Anhui Province, China. xiaxm2000@hotmail.com
Telephone: +86-551-2887190 Fax: +86-551-2876038
Received: October 18, 2011
Revised: March 3, 2012
Accepted: March 9, 2012
Published online: May 7, 2012
Abstract

AIM: To investigate the effect of emodin on pancreatic claudin-5 and occludin expression, and pancreatic paracellular permeability in acute pancreatitis (AP).

METHODS: Experimental pancreatitis was induced by retrograde injection of 5% sodium taurocholate into the biliopancreatic duct. Emodin was injected via the external jugular vein 0 or 6 h after induction of AP. Rats from sham operation and AP groups were injected with normal saline at the same time. Samples of pancreas were obtained 6 or 12 h after drug administration. Pancreatic morphology was examined with hematoxylin and eosin staining. Pancreatic edema was estimated by measuring tissue water content. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 level were measured by enzyme-linked immunosorbent assay. Pancreatic paracellular permeability was assessed by tissue dye extravasation. Expression of pancreatic claudin-5 and occludin was examined by immunohistology, quantitative real-time reverse transcriptase polymerase chain reaction and western blotting.

RESULTS: Pancreatic TNF-α and IL-6 levels, wet/dry ratio, dye extravasation, and histological score were significantly elevated at 3, 6 and 12 h following sodium taurocholate infusion; treatment with emodin prevented these changes at all time points. Immunostaining of claudin-5 and occludin was detected in rat pancreas, which was distributed in pancreatic acinar cells, ductal cells and vascular endothelial cells, respectively. Sodium taurocholate infusion significantly decreased pancreatic claudin-5 and occludin mRNA and protein levels at 3, 6 and 12 h, and that could be promoted by intravenous administration of emodin at all time points.

CONCLUSION: These results demonstrate that emodin could promote pancreatic claudin-5 and occludin expression, and reduce pancreatic paracellular permeability.

Keywords: Acute pancreatitis; Paracellular permeability; Emodin; Claudin; Occludin