Basic Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Dec 15, 2020; 11(12): 611-621
Published online Dec 15, 2020. doi: 10.4239/wjd.v11.i12.611
Effect of liraglutide on endoplasmic reticulum stress in the renal tissue of type 2 diabetic rats
Xuan-Ye Zhao, Ting-Ting Yu, Sheng Liu, Yao-Ji Liu, Jing-Jin Liu, Jie Qin
Xuan-Ye Zhao, Ting-Ting Yu, Sheng Liu, Yao-Ji Liu, Jing-Jin Liu, Jie Qin, Department of Endocrinology, Shanxi Provincial People's Hospital, Taiyuan 030012, Shanxi Province, China
Author contributions: Qin J designed the research study; Zhao XY performed the research and wrote the manuscript; Yu TT and Liu S contributed to the purchase of new reagents and analytic tools; Liu YJ and Liu JJ analyzed the data; all authors have read and approved the final manuscript.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of Shanxi Provincial People's Hospital.
Institutional animal care and use committee statement: All animal experiments were approved by the Medical Ethics Committee of Shanxi Provincial People's Hospital.
Conflict-of-interest statement: The authors declare that they have no conflicts of interest to disclose.
Data sharing statement: No additional data are available.
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: Jie Qin, MD, Chief Doctor, Department of Endocrinology, Shanxi Provincial People's Hospital, No. 29 Shuangtasi Street, Taiyuan 030012, Shanxi Province, China. bxl5cnfmsys@163.com
Received: August 10, 2020
Peer-review started: August 10, 2020
First decision: September 21, 2020
Revised: September 28, 2020
Accepted: October 21, 2020
Article in press: October 21, 2020
Published online: December 15, 2020
Processing time: 124 Days and 21.1 Hours
Abstract
BACKGROUND

Liraglutide is a glucagon-like peptide 1 receptor agonist analog that has been found to have a therapeutic effect in diabetes. In addition to its ability to treat diabetes, liraglutide has beneficial effects on the cardiovascular system and kidney as well as other beneficial effects, but its specific mechanism is not clear. In this study, a rat model of type 2 diabetes was established by administration of a high-sugar, high-fat diet combined with low-dose streptozotocin (STZ) to observe the effect of liraglutide on the kidneys of type 2 diabetes rats and the possible underlying mechanisms.

AIM

To explore whether liraglutide has a protective effect on type 2 diabetic rat kidneys and the underlying mechanisms.

METHODS

Eight-week-old male Sprague-Dawley rats were randomly divided into a control group, model group, low-dose liraglutide group, and high-dose liraglutide group. Control rats were fed a standard diet, while model group and intervention group rats were fed high-sugar, high-fat feed for 1 mo and then intraperitoneally injected with 40 mg/kg STZ to induce type 2 diabetes. The low-dose and high-dose intervention groups received 100 µg/kg and 200 µg/kg liraglutide, respectively, once daily by subcutaneous injection. The control and model groups were given an equivalent volume of physiological saline for 8 wk. Pathological changes in renal tissues were observed by hematoxylin and eosin staining and periodic acid-Schiff staining, and GRP78 and caspase-12 expression was detected by Western blot and reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Western blot analysis showed that GRP78 and caspase-12 protein expression in kidney tissue was significantly higher in model rats than in normal rats and lower in the liraglutide-treated groups than in the model group, with a more significant decrease being observed in the high-dose group than in the low-dose group. RT-PCR showed that the mRNA expression of GRP78 and caspase-12 was higher in model rats than in control rats and lower in the liraglutide-treated groups than in the model group, with the high-dose group exhibiting a more significant decrease than the low-dose group.

CONCLUSION

Liraglutide may delay the progression of diabetic nephropathy by reducing endoplasmic reticulum stress and protect the kidneys in a dose-dependent manner.

Keywords: Liraglutide; Diabetes; Diabetic nephropathy; Endoplasmic reticulum stress; Rat; Nephropathy

Core Tip: This study explored whether liraglutide has a protective effect on type 2 diabetic rat kidneys and the underlying mechanisms using experimental animals. The conclusion is that liraglutide may delay the progression of diabetic nephropathy by reducing endoplasmic reticulum stress and protect the kidneys in a dose-dependent manner.