Original Article
Copyright ©2011 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jun 14, 2011; 17(22): 2748-2773
Published online Jun 14, 2011. doi: 10.3748/wjg.v17.i22.2748
miRNA studies in in vitro and in vivo activated hepatic stellate cells
Gunter Maubach, Michelle Chin Chia Lim, Jinmiao Chen, Henry Yang, Lang Zhuo
Gunter Maubach, Michelle Chin Chia Lim, Lang Zhuo, Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos #04-01, Singapore 138669, Singapore
Gunter Maubach, Institute of Experimental Internal Medicine, Leipziger Strasse 44, Magdeburg 39120, Germany
Jinmiao Chen, Henry Yang, Bioinformatics Lab, Singapore Immunology Network, 8A Biomedical Grove, Singapore 138648, Singapore
Author contributions: Maubach G was involved in the conceptualization of the study, the design and carrying out of the experiments, and writing of the manuscript; Lim MCC performed the experiments and was also involved in editing the manuscript; Chen J and Yang H performed the analysis of the microarray data and edited the manuscript; Zhuo L engaged in the design of the study and writing of the manuscript.
Supported by Institute of Bioengineering and Nanotechnology (Biomedical Research Council, Agency for Science, Technology and Research, Singapore)
Correspondence to: Dr. Lang Zhuo, Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos #04-01, Singapore 138669, Singapore. lzhuo@ibn.a-star.edu.sg
Telephone: +65-68247114 Fax: +65-64789080
Received: May 19, 2010
Revised: September 14, 2010
Accepted: September 21, 2010
Published online: June 14, 2011

AIM: To understand which and how different miRNAs are implicated in the process of hepatic stellate cell (HSC) activation.

METHODS: We used microarrays to examine the differential expression of miRNAs during in vitro activation of primary HSCs (pHSCs). The transcriptome changes upon stable transfection of rno-miR-146a into an HSC cell line were studied using cDNA microarrays. Selected differentially regulated miRNAs were investigated by quantitative real-time polymerase chain reaction during in vivo HSC activation. The effect of miRNA mimics and inhibitor on the in vitro activation of pHSCs was also evaluated.

RESULTS: We found that 16 miRNAs were upregulated and 26 were downregulated significantly in 10-d in vitro activated pHSCs in comparison to quiescent pHSCs. Overexpression of rno-miR-146a was characterized by marked upregulation of tissue inhibitor of metalloproteinase-3, which is implicated in the regulation of tumor necrosis factor-α activity. Differences in the regulation of selected miRNAs were observed comparing in vitro and in vivo HSC activation. Treatment with miR-26a and 29a mimics, and miR-214 inhibitor during in vitro activation of pHSCs induced significant downregulation of collagen type I transcription.

CONCLUSION: Our results emphasize the different regulation of miRNAs in in vitro and in vivo activated pHSCs. We also showed that miR-26a, 29a and 214 are involved in the regulation of collagen type I mRNA.

Keywords: Hepatic stellate cells, miRNA, miR-146a, Nuclear factor-κB