Basic Research
Copyright ©2008 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Apr 21, 2008; 14(15): 2349-2357
Published online Apr 21, 2008. doi: 10.3748/wjg.14.2349
Vascular endothelial growth factor attenuates hepatic sinusoidal capillarization in thioacetamide-induced cirrhotic rats
Hao Xu, Bao-Min Shi, Xiao-Fei Lu, Feng Liang, Xing Jin, Tai-Huang Wu, Jian Xu
Hao Xu, Bao-Min Shi, Xiao-Fei Lu, Feng Liang, Tai-Huang Wu, Jian Xu, Department of Hepatobiliary and Pancreas Surgery, Shandong Provincial Hospital, Clinical College of Shandong University, Jinan 250021, Shandong Province, China
Hao Xu, Xing Jin, Department of Vascular Surgery, Shandong Provincial Hospital, Clinical College of Shandong University, Jinan 250021, Shandong Province, China
Author contributions: Xu H and Shi BM contributed equally to this work; Xu H, Shi BM, Lu XF, Liang F, Jin X, Wu TH and Xu J designed the research; Xu H, Shi BM, Lu XF and Liang F performed the research; Lu XF and Liang F contributed new reagents/analytic tools; Xu H, Shi BM and Jin X analyzed the data; and Xu H and Shi BM wrote the paper.
Correspondence to: Dr. Bao-Min Shi, Department of Hepatobiliary and Pancreas Surgery, Shandong Provincial Hospital, Clinical College of Shandong University, 324 Jingwu Road, Jinan 250021, Shandong Province, China. baomins@tom.com
Telephone: +86-531-85186363
Fax: +86-531-87068707
Received: November 17, 2007
Revised: February 15, 2008
Published online: April 21, 2008
Abstract

AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization.

METHODS: Enhanced green fluorescent protein (EGFP)/VEGF transfection was confirmed by immunofluorescence microscopy and immunohistoche-mistry both in primary hepatocytes and in normal liver. Cirrhotic rats were generated by thioacetamide (TAA) administration and then divided into a treatment group, which received injections of 400 &mgr;g of plasmid DNA encoding an EGFP-VEGF fusion protein, and a blank group, which received an equal amount of normal saline through the portal vein. The portal vein pressure was measured in the normal and cirrhotic state, in treated and blank groups. The average number of fenestrae per hepatic sinusoid was determined using transmission electron microscopy (TEM), while the relative abundance of VEGF transcripts was examined by Gene array.

RESULTS: Green fluorescent protein was observed in the cytoplasms of liver cells under immunofluorescence microscopy 24 h after transfection with EGFP/VEGF plasmid in vitro. Staining with polyclonal antibodies against VEGF illustrated that hepatocytes expressed immunodetectable VEGF both in vitro and in vitro. There were significant differences in the number of fenestrae and portal vein pressures between normal and cirrhotic rats (7.40 ± 1.71 vs 2.30 ± 1.16 and 9.32 ± 0.85 cmH2O vs 17.92 ± 0.90 cmH2O, P < 0.01), between cirrhotic and treated rats (2.30 ± 1.16 cmH2O vs 4.60 ± 1.65 and 17.92 ± 0.90 cmH2O vs 15.52 ± 0.93 cmH2O, P < 0.05) and between the treatment group and the blank group (4.60 ± 1.65 cmH2O vs 2.10 ± 1.10 cmH2O and 15.52 ± 0.93 cmH2O vs 17.26 ± 1.80 cmH2O, P < 0.05). Gene-array analysis revealed that the relative abundance of transcripts of VEGF family members decreased in the cirrhotic state and increased after transfection.

CONCLUSION: Injection of a plasmid encoding VEGF through the portal vein is an effective method to induce the formation of fenestrae and decrease portal vein pressure in cirrhotic rats. Therefore, it may be a good choice for treating hepatic cirrhosis and portal hypertension.

Keywords: Liver cirrhosis; Hepatic sinusoid capillarization; Fenestrae; Vascular endothelial growth factor; Transmission electrical microscopy; Ultrastructure; Gene array