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:
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.
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
Research background

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide. However, there is no Food and Drug Administration (FDA) approved medication for the treatment of NAFLD. Aloe vera has previously been shown to have anti-inflammatory and anti-oxidant properties, which might be beneficial in the treatment of NAFLD.

Research motivation

With the absence of FDA-approved treatment for NAFLD, we attempted to find a safe and effective treatment for NAFLD. Alternative medicines that are safe, effective and inexpensive are attractive options for the management of life-long diseases, such as non-alcoholic steatohepatitis (NASH).

Research objectives

The main objective of this study was to evaluate the effects of aloe vera on NASH development in an animal model.

Research methods

Rats were divided into 3 groups: Control, NASH [rats received high-fat high-fructose diet (HFHFD) to induce NASH pathology], and NASH + aloe vera. We compared liver histopathology, oxidative stress marker [malondialdehyde (MDA)], anti-oxidant level [glutathione (GSH)], inflammatory marker (IL-18), degree and markers of hepatocyte apoptosis [terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), caspase-3, cytochrome-C], and PPAR-γ expression among the three groups.

Research results

We found that by administering aloe vera along with HFHFD, we were able to significantly reduce the severity of NASH pathology in this animal model. In this study, aloe vera treatment increased the level of natural anti-oxidant (GSH), reduced oxidative stress (MDA) and inflammatory markers (IL-18), and decreased the degree of hepatocyte apoptosis (TUNEL). At the subcellular level, we also found that aloe vera increased the expression of PPAR-γ and reduced the expression of NF-kβ, caspase-3 and cytochrome-C.

Research conclusions

This is the first study to evaluate the effects of aloe vera in rats with NASH. We found that aloe vera reduced the severity of NASH pathology in rats that received HFHFD. We hypothesized that aloe vera exerted its treatment effects by reducing oxidative stress and inflammation in the liver.

Research perspectives

The rats in our model were lean, so our results might not be entirely applicable to obese NASH that is seen more commonly in humans. Further studies with an obese rat model are warranted to confirm the effects of aloe vera in those conditions. Moreover, we used aloe vera crude extract in this study. Additional studies will be needed to identify the active ingredients in aloe vera that have anti-NASH effects.