Basic Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 21, 2015; 21(35): 10091-10103
Published online Sep 21, 2015. doi: 10.3748/wjg.v21.i35.10091
Broccoli sprout extract induces detoxification-related gene expression and attenuates acute liver injury
Kazutaka Yoshida, Yusuke Ushida, Tomoko Ishijima, Hiroyuki Suganuma, Takahiro Inakuma, Nobuhiro Yajima, Keiko Abe, Yuji Nakai
Kazutaka Yoshida, Yusuke Ushida, Hiroyuki Suganuma, Nobuhiro Yajima, Research and Development Division, Kagome Co., Ltd., Nasushiobara 329-2762, Japan
Tomoko Ishijima, Keiko Abe, Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
Takahiro Inakuma, Faculty of Contemporary Human Life Science, Department of Food and Nutrition, Tezukayama University, Nara 631-8585, Japan
Yuji Nakai, Institute for Food Science, Hirosaki University, Aomori 038-0012, Japan
Author contributions: Yoshida K, Ushida Y, Suganuma H, Inakuma T, Abe K and Nakai Y designed the research; Ushida Y performed the animal experiments and biological analysis; Yoshida K, Ishijima T, Yajima N and Nakai Y performed the molecular biology experiments and data analysis; Yoshida K, Yajima N, Abe K and Nakai Y wrote the paper; all the authors approved the final manuscript.
Supported by Kagome Co. Ltd.
Institutional review board statement: This study is not human study, so there is no Institutional Review Board statement to disclose.
Institutional animal care and use committee statement: The animal experiment protocol was approved by the Committee on the Care and Use of Laboratory Animals of the Kagome Animal Use Committee (2007.005, 2007.016, and 2008.011).
Conflict-of-interest statement: No potential conflict of interest to disclose.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at “kazutaka_yoshida@kagome.co.jp”.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Kazutaka Yoshida, Scientist, Research and Development Division, Kagome Co., Ltd., 17 Nishitomiyama, Nasushiobara 329-2762, Japan. kazutaka_yoshida@kagome.co.jp
Telephone: +81-287-362935 Fax: +81-287-391038
Received: February 13, 2015
Peer-review started: February 22, 2015
First decision: March 26, 2015
Revised: May 25, 2015
Accepted: July 3, 2015
Article in press: July 3, 2015
Published online: September 21, 2015
Abstract

AIM: To investigate the effects of broccoli sprout extract (BSEx) on liver gene expression and acute liver injury in the rat.

METHODS: First, the effects of BSEx on liver gene expression were examined. Male rats were divided into two groups. The Control group was fed the AIN-76 diet, and the BSEx group was fed the AIN-76 diet containing BSEx. After a 10-d feeding period, rats were sacrificed and their livers were used for DNA microarray and real-time reverse transcription-polymerase chain reaction (RT-PCR) analyses. Next, the effects of BSEx on acute liver injury were examined. In experiments using acute liver injury models, 1000 mg/kg acetaminophen (APAP) or 350 mg/kg D-galactosamine (D-GalN) was used to induce injury. These male rats were divided into four groups: Control, BSEx, Inducer (APAP or D-GalN), and Inducer+BSEx. The feeding regimens were identical for the two analyses. Twenty-four hours following APAP administration via p.o. or D-GalN administration via i.p., rats were sacrificed to determine serum aspartate transaminase (AST) and alanine transaminase (ALT) levels, hepatic glutathione (GSH) and thiobarbituric acid-reactive substances accumulation and glutathione-S-transferase (GST) activity.

RESULTS: Microarray and real-time RT-PCR analyses revealed that BSEx upregulated the expression of genes related to detoxification and glutathione synthesis in normal rat liver. The levels of AST (70.91 ± 15.74 IU/mL vs 5614.41 ± 1997.83 IU/mL, P < 0.05) and ALT (11.78 ± 2.08 IU/mL vs 1297.71 ± 447.33 IU/mL, P < 0.05) were significantly suppressed in the APAP + BSEx group compared with the APAP group. The level of GSH (2.61 ± 0.75 nmol/g tissue vs 1.66 ± 0.59 nmol/g tissue, P < 0.05) and liver GST activity (93.19 ± 16.55 U/g tissue vs 51.90 ± 16.85 U/g tissue, P < 0.05) were significantly increased in the APAP + BSEx group compared with the APAP group. AST (4820.05 ± 3094.93 IU/mL vs 12465.63 ± 3223.97 IU/mL, P < 0.05) and ALT (1808.95 ± 1014.04 IU/mL vs 3936.46 ± 777.52 IU/mL, P < 0.05) levels were significantly suppressed in the D-GalN + BSEx group compared with the D-GalN group, but the levels of AST and ALT in the D-GalN + BSEx group were higher than those in the APAP + BSEx group. The level of GST activity was significantly increased in the D-GalN + BSEx group compared with the D-GalN group (98.04 ± 15.75 U/g tissue vs 53.15 ± 8.14 U/g tissue, P < 0.05).

CONCLUSION: We demonstrated that BSEx protected the liver from various types of xenobiotic substances through induction of detoxification enzymes and glutathione synthesis.

Keywords: Broccoli sprout, Galactosamine, Acute liver injury, Glucoraphanin, Sulforaphane, DNA microarray, Acetaminophen

Core tip: The aim of this study was to investigate the effects of broccoli sprout extract (BSEx) on gene expression and acute liver injury in rat liver. Gene expression analyses revealed that BSEx upregulated the expression of genes related to detoxification and glutathione synthesis. Experiments using acute liver injury models revealed that BSEx suppressed acetaminophen- and D-galactosamine-induced liver injury and increased liver glutathione concentration and glutathione-S-transferase activity. These findings suggest that consuming BSEx daily protected the liver from various types of xenobiotic substances through induction of detoxification enzymes and glutathione synthesis.