Basic Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Jul 27, 2020; 12(7): 363-377
Published online Jul 27, 2020. doi: 10.4254/wjh.v12.i7.363
Anti-inflammatory and anti-oxidant effects of aloe vera in rats with non-alcoholic steatohepatitis
Naruemon Klaikeaw, Jutamas Wongphoom, Duangporn Werawatganon, Maneerat Chayanupatkul, Prasong Siriviriyakul
Naruemon Klaikeaw, Jutamas Wongphoom, Department of Pathology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
Duangporn Werawatganon, Maneerat Chayanupatkul, Prasong Siriviriyakul, Alternative and Complementary Medicine for Gastrointestinal and Liver Diseases Research Unit, Department of Physiology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
Author contributions: Klaikeaw N, Werawatganon D and Siriviriyakul P designed the study; Klaikeaw N, Wongphoom J and Werawatganon D performed the experiments; Klaikeaw N performed pathological examinations; Wongphoom J collected the data; Wongphoom J, Werawatganon D, Chayanupatkul M and Siriviriyakul P analyzed the data; Werawatganon D edited the manuscript; Chayanupatkul M wrote the manuscript; Siriviriyakul P revised the manuscript.
Supported by the Grant of Ratchadaphiseksomphot, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, No. RA59/035.
Institutional review board statement: The study was reviewed and approved by the Ethical Committee, Faculty of Medicine, Chulalongkorn University, Thailand (IRB No.12/58).
Institutional animal care and use committee statement: That in vivo experiments were performed only after receiving formal authorization by the Institutional “Animal Care and Use Committee” of the Chulalongkorn University, Bangkok, Thailand. The procedures for the care and handling of the animals used in the study were in accordance with the European Directive 2010/63/EU on the protection of animals used for scientific purposes.
Conflict-of-interest statement: No potential conflicts of interest relevant to this article were reported.
Data sharing statement: The data that support the findings of this study are available from the corresponding author, upon reasonable request.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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/
Corresponding author: Duangporn Werawatganon, MD, MSc, Professor, Alternative and Complementary Medicine for Gastrointestinal and Liver Diseases Research Unit, Department of Physiology, Faculty of Medicine, Chulalongkorn University, Henri Dunant Road, Pathumwan, Bangkok 10330, Thailand. dr.duangporn@gmail.com
Received: February 13, 2020
Peer-review started: February 13, 2020
First decision: April 29, 2020
Revised: May 12, 2020
Accepted: May 29, 2020
Article in press: May 29, 2020
Published online: July 27, 2020
Processing time: 160 Days and 20.1 Hours
Abstract
BACKGROUND

Aloe vera exerts several biological activities, such as, anti-inflammatory, antioxidant, and antimicrobial effects. It was recently shown to reduce insulin resistance and triglyceride level. We hypothesized that aloe vera would have beneficial effects in alleviating non-alcoholic steatohepatitis (NASH) in rats.

AIM

To examine the therapeutic effects of aloe vera in NASH rats.

METHODS

All rats were randomly divided into 3 groups (n = 6 in each group). Rats in the control group were fed ad libitum with a standard diet for 8 wk. Rats in the NASH group were fed ad libitum with a high-fat high-fructose diet (HFHFD) for 8 wk. Rats in the aloe vera group were fed ad libitum with a HFHFD and aloe vera in dimethylsulfoxide (50 mg/kg) by gavage daily for 8 wk. Liver samples were collected at the end of the treatment period.

RESULTS

Hepatic malondialdehyde (MDA) levels increased significantly in the NASH group as compared with the control group (377 ± 77 nmol/mg vs 129 ± 51 nmol/mg protein, respectively, P < 0.001). Glutathione (GSH) levels were significantly lower in the NASH group than the control group (9 ± 2 nmol/mg vs 24 ± 8 nmol/mg protein, respectively, P = 0.001). The expression of interleukin-18 (IL-18), nuclear factor-kappa β, and caspase-3 increased, while peroxisome proliferator-activated receptor gamma decreased in the NASH group compared with the controls. Following aloe vera administration, MDA levels decreased (199 ± 35 nmol/mg protein) and GSH increased (18 ± 4 nmol/mg protein) markedly. Steatosis, hepatocyte ballooning, lobular inflammation and increased hepatocyte apoptosis were observed in the NASH group. Aloe vera treatment attenuated these changes in liver histology.

CONCLUSION

Aloe vera attenuated oxidative stress, hepatic inflammation and hepatocyte apoptosis, thus improving liver pathology in rats with NASH.

Keywords: Non-alcoholic steatohepatitis; Aloe vera; Oxidative stress; Hepatic inflammation; Hepatocyte apoptosis; Peroxisome proliferator-activated receptor

Core tip: To the best of our knowledge, this is the first study to evaluate the therapeutic effects of aloe vera in non-alcoholic steatohepatitis (NASH). In this animal model of NASH, we found that aloe vera decreased oxidative stress markers, replenished natural antioxidants, and reduced hepatic inflammation and hepatocyte apoptosis. Thus, aloe vera can alleviate the pathologic changes seen in NASH.