Basic Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Mar 15, 2020; 11(3): 52-65
Published online Mar 15, 2020. doi: 10.4239/wjd.v11.i3.52
Vitamin C ameliorated cardiac autonomic neuropathy in type 2 diabetic rats
Temitope Deborah Fabiyi-Edebor
Temitope Deborah Fabiyi-Edebor, Department of Physiology, Afe Babalola University Ado Ekiti, Ado 5454, Ekiti, Nigeria
Author contributions: Fabiyi-Edebor TD designed and performed the research, analysed the data and wrote the paper.
Institutional review board statement: The study was reviewed and approved by Afe Babalola University Institutional Review board.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of Afe Babalola University with protocol number: [ABUAD-IRB/IACAU/2018/131].
Conflict-of-interest statement: There is no conflict of interest regarding this manuscript.
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: Temitope Deborah Fabiyi-Edebor, PhD, Senior Lecturer, Department of Physiology, Afe Babalola University Ado Ekiti, Kilometres 8.5 Afe Babalola Way, Ado 5454, Ekiti, Nigeria. fabiyitd@abuad.edu.ng
Received: August 6, 2019
Peer-review started: September 8, 2019
First decision: September 21, 2019
Revised: December 7, 2019
Accepted: January 13, 2020
Article in press: January 13, 2020
Published online: March 15, 2020
ARTICLE HIGHLIGHTS
Research background

Complications of diabetes such as cardiac autonomic neuropathy has been attributed to increased oxidative stress secondary to hyperglycaemia. This makes reduction of oxidative stress an attractive therapeutic pathway in the prevention and/or management of cardiac autonomic neuropathy. Thus, this study hypothesises that administration of high dose of 1 g/kg·d of vitamin C (VC) to type 2 diabetic subjects may prevent or ameliorate cardiac autonomic neuropathy.

Research motivation

The motivation for this study is to increase the quality of life of diabetics, reducing the morbidity and mortality due to cardiovascular and neuronal events in them. This study proposes that high dose VC may possess neuronal and cardio protective effects thus preventing or ameliorating cardiac autonomic neuropathy in diabetic subjects.

Research objectives

The main objectives of this study were to evaluate the cardiovascular ad neuro- protective effects of VC administration in diabetics. The effects of VC on cardiovascular functions, autonomic functions, oxidative stress and lipid metabolism were investigated.

Research methods

Heart rate variability electrophysiology was employed to assess cardiac autonomic neuropathy in Wistar rats. Tail flick blood pressure monitor was used to assess cardiovascular functions such as blood pressure and heart rate. Apolipoproteins were measured using immunoturbidimetry, oxidative and inflammatory markers were measured spectrophotometrically while tyrosine hydroxylase immunohistochemistry was employed to study autonomic activity in the heart.

Research results

The findings of this study reveal that VC reversed cardiac autonomic neuropathy in diabetics and thus might be a useful adjuvant in the management of diabetes to improve the quality of life of diabetics. VC effects on other diabetic neuropathies should be evaluated. Also, VC as an adjuvant therapy to diabetic patients should be investigated in clinical trials.

Research conclusions

This study hypothesises that VC may ameliorate cardiac autonomic neuropathy. VC was found to reverse abnormal heart rate variability and preserve normal cardiovascular functions, protect autonomic nerves from oxidative damage and to possess lipid lowering potential in diabetic condition. The implication of this study is that VC may be used in the management of diabetic patients to prevent the progression of neuropathies and cardiovascular events in them, thereby improving their quality of life.

Research perspectives

Human studies may be needed to evaluate VC effects in diabetic patients. Interactions of VC with antidiabetic drugs in diabetic subjects should be examined. Also, further studies are required to elucidate the molecular pathway via which VC exert cardio- and neuro- protective effects in diabetic condition.