Original Article
Copyright ©2014 Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Aug 27, 2014; 6(8): 613-620
Published online Aug 27, 2014. doi: 10.4254/wjh.v6.i8.613
Circulating microRNAs in patients with non-alcoholic fatty liver disease
Mehmet Celikbilek, Mevlut Baskol, Serpil Taheri, Kemal Deniz, Serkan Dogan, Gokmen Zararsiz, Sebnem Gursoy, Kadri Guven, Omer Ozbakır, Munis Dundar, Mehmet Yucesoy
Mehmet Celikbilek, Mevlut Baskol, Serkan Dogan, Sebnem Gursoy, Kadri Guven, Omer Ozbakır, Mehmet Yucesoy, Department of Gastroenterology, Erciyes University, Medical School, 38039 Kayseri, Turkey
Serpil Taheri, Munis Dundar, Department of Medical Genetics, Erciyes University, Medical School, 38039 Kayseri, Turkey
Kemal Deniz, Department of Pathology, Erciyes University, Medical School, 38039 Kayseri, Turkey
Gokmen Zararsiz, Department of Biostatistics and Medical Informatics, Erciyes University, Medical School, 38039 Kayseri, Turkey
Author contributions: Celikbilek M, Taheri S and Dogan S contributed to the design of the study, data collection, drafted the manuscript, and revised it in accordance with suggestions from the other authors; Baskol M contributed to the design of the study, drafted the manuscript and participated in the critical revision of the manuscript for important intellectual content; Deniz K contributed to the study conception and design, analysis and interpretation of data, drafted the manuscript, and participated in the critical revision of the manuscript for important intellectual content; Zararsız G performed the statistical and bioinformatics analysis; Gursoy S, Guven K, Ozbakır O, Dundar M, Yucesoy M contributed to the design of the study, interpretation of data, and participated in the critical revision of the manuscript for important intellectual content.
Correspondence to: Mehmet Celikbilek, MD, Department of Gastroenterology, Erciyes University, Medical School, 38039 Kayseri, Turkey. drcelikbilek@yahoo.com
Telephone: +90-505-6615375 Fax: +90-354-2140612
Received: January 28, 2014
Revised: March 13, 2014
Accepted: July 12, 2014
Published online: August 27, 2014
Processing time: 212 Days and 9.9 Hours
Abstract

AIM: To identify novel non-invasive biomarkers for non-alcoholic fatty liver disease (NAFLD).

METHODS: Twenty patients with histologically proven NAFLD and 20 controls were included. All NAFLD cases were scored using the NAFLD activity score. The relative expressions of miR-197, miR-146b, miR-10b, miR-181d, miR-34a, miR-122, miR-99a and miR-29a were analyzed using real-time polymerase chain reaction.

RESULTS: Serum levels of miR-181d, miR-99a, miR-197 and miR-146b were significantly lower in biopsy-proven NAFLD patients than in the healthy controls. Serum levels of miR-197 and miR-10b were inversely correlated with degree of inflammation and miR-181d and miR-99a were inversely correlated with serum gamma glutamyl transferase levels in non-alcoholic steatohepatitis patients.

CONCLUSION: NAFLD is associated with altered serum miRNA expression pattern. This study provides clues for defining the non-invasive diagnosis of NAFLD.

Keywords: Nonalcoholic fatty liver disease; Nonalcoholic steatohepatitis; MicroRNA; Noninvasive; Serum markers

Core tip: Due to the limitations of liver biopsy, the use of non-invasive markers has emerged in recent years. MicroRNAs (miRNAs) are a class of naturally occurring small noncoding RNAs that regulate gene expression. Altered miRNA expression has been reported in animal and human liver samples in non-alcoholic fatty liver disease (NAFLD). There is, however, only limited information on their detection in blood and their correlation with histological disease severity in patients with NAFLD. For this reason, we measured the serum levels of some miRNAs in non-alcoholic steatohepatitis (NASH) patients. Of these microRNAs, miR-181d, miR-99a, miR-197 and miR-146b were expressed at lower levels in NASH patients than in controls. Serum levels of miR-197 and miR-10b were inversely correlated with degree of inflammation and miR-181d and miR-99a were inversely correlated with serum gamma glutamyl transferase levels in NASH patients.