Next Article in Journal
Metabolomic Fingerprinting in the Comprehensive Study of Liver Changes Associated with Onion Supplementation in Hypercholesterolemic Wistar Rats
Previous Article in Journal
Dimethyl Fumarate Therapy Significantly Improves the Responsiveness of T Cells in Multiple Sclerosis Patients for Immunoregulation by Regulatory T Cells
Article Menu
Issue 2 (February) cover image

Export Article

Open AccessArticle
Int. J. Mol. Sci. 2017, 18(2), 285; doi:10.3390/ijms18020285

Insulin Production and Resistance in Different Models of Diet-Induced Obesity and Metabolic Syndrome

1
Clinic for Gastroenterology and Endocrinology, University Medical Center, Georg-August-University Goettingen, Goettingen D-37075, Germany
2
MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, UK
3
Endocrinology Unit, University/BHF Centre for Cardiovascular Science, Queen’s Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
4
Advanced Liver and Gastrointestinal Disease Center, Chicago, IL 60611, USA
*
Authors to whom correspondence should be addressed.
Academic Editor: Giovanni Tarantino
Received: 13 December 2016 / Revised: 13 January 2017 / Accepted: 17 January 2017 / Published: 28 January 2017
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
View Full-Text   |   Download PDF [9184 KB, uploaded 13 February 2017]   |  

Abstract

The role of the liver and the endocrine pancreas in development of hyperinsulinemia in different types of obesity remains unclear. Sedentary rats (160 g) were fed a low-fat-diet (LFD, chow 13% kcal fat), high-fat-diet (HFD, 35% fat), or HFD+ 30% ethanol+ 30% fructose (HF-EFr, 22% fat). Overnight-fasted rats were culled after one, four or eight weeks. Pancreatic and hepatic mRNAs were isolated for subsequent RT-PCR analysis. After eight weeks, body weights increased three-fold in the LFD group, 2.8-fold in the HFD group, and 2.4-fold in the HF-EFr (p < 0.01). HF-EFr-fed rats had the greatest liver weights and consumed less food during Weeks 4–8 (p < 0.05). Hepatic-triglyceride content increased progressively in all groups. At Week 8, HOMA-IR values, fasting serum glucose, C-peptide, and triglycerides levels were significantly increased in LFD-fed rats compared to that at earlier time points. The greatest plasma levels of glucose, triglycerides and leptin were observed in the HF-EFr at Week 8. Gene expression of pancreatic-insulin was significantly greater in the HFD and HF-EFr groups versus the LFD. Nevertheless, insulin: C-peptide ratios and HOMA-IR values were substantially higher in HF-EFr. Hepatic gene-expression of insulin-receptor-substrate-1/2 was downregulated in the HF-EFr. The expression of phospho-ERK-1/2 and inflammatory-mediators were greatest in the HF-EFr-fed rats. Chronic intake of both LFD and HFD induced obesity, MetS, and intrahepatic-fat accumulation. The hyperinsulinemia is the strongest in rats with the lowest body weights, but having the highest liver weights. This accompanies the strongest increase of pancreatic insulin production and the maximal decrease of hepatic insulin signaling, which is possibly secondary to hepatic fat deposition, inflammation and other factors. View Full-Text
Keywords: alcohol; insulin resistance; type II diabetes mellitus (T2DM); obesity; fatty liver alcohol; insulin resistance; type II diabetes mellitus (T2DM); obesity; fatty liver
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Supplementary material

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Alwahsh, S.M.; Dwyer, B.J.; Forbes, S.; van Thiel, D.H.; Starkey Lewis, P.J.; Ramadori, G. Insulin Production and Resistance in Different Models of Diet-Induced Obesity and Metabolic Syndrome. Int. J. Mol. Sci. 2017, 18, 285.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top