Effects of hepatic triglyceride content on myocardial metabolism in type 2 diabetes.

Abstract

OBJECTIVES:

The purpose of this study was to investigate the relationship between hepatic triglyceride content and both myocardial function and metabolism in type 2 diabetes mellitus (T2DM).

BACKGROUND:

Heart disease is the leading cause of mortality in T2DM. Central obesity and hepatic steatosis, both hallmark abnormalities in T2DM, have been related to increased risk of heart disease.

METHODS:

Sixty-one T2DM patients underwent myocardial perfusion and substrate metabolism measurements by positron emission tomography, using [15O]water, [11C]palmitate, and [18F]-2-fluoro-2-deoxy-D-glucose. In addition, whole-body insulin sensitivity (M/I) was determined. Myocardial left ventricular function and high-energy phosphate metabolism were measured using magnetic resonance imaging and [31P]-magnetic resonance spectroscopy, respectively. Hepatic triglyceride content was measured by proton magnetic resonance spectroscopy. Patients were divided according to hepatic triglyceride content (T2DM-low<or=5.56% vs. T2DM-high>5.56%).

RESULTS:

In addition to decreased M/I (p=0.002), T2DM-high patients had reduced myocardial perfusion (p=0.001), glucose uptake (p=0.005), and phosphocreatine/adenosine triphosphate (PCr/ATP) ratio (p=0.003), compared with T2DM-low patients, whereas cardiac fatty acid metabolism and left ventricular function were not different. Hepatic triglyceride content correlated inversely with M/I (Pearson's r=-0.620, p<0.001), myocardial glucose uptake (r=-0.413, p=0.001), and PCr/ATP (r=-0.442, p=0.027). Insulin sensitivity correlated positively with myocardial glucose uptake (r=0.528, p<0.001) and borderline with myocardial PCr/ATP (r=0.367, p=0.072), whereas a positive association was found between cardiac glucose uptake and PCr/ATP (r=0.481, p=0.015).

CONCLUSIONS:

High liver triglyceride content in T2DM was associated with decreased myocardial perfusion, glucose uptake, and high-energy phosphate metabolism in conjunction with impaired M/I. The long-term clinical implications of hepatic steatosis with respect to cardiac metabolism and function in the course of T2DM require further study.

• Authors: Luuk J Rijzewijk, Jacqueline T Jonker, Rutger W van der Meer, Mark Lubberink, Hugo W de Jong, Johannes A Romijn, Jeroen J Bax, Albert de Roos, Robert J Heine, Jos W Twisk, Albert D Windhorst, Adriaan A Lammertsma, Johannes W A Smit, Michaela Diamant, Hildo J Lamb
• Journal: Journal of the American College of Cardiology (J Am Coll Cardiol) Vol. 56 Issue 3 Pg. 225-33 (Jul 13 2010) ISSN: 1558-3597 [Electronic] United States
• PMID: 20620743 (Publication Type: Journal Article)
• Copyright: Copyright (c) 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Chemical References

• Phosphates
• Triglycerides
• Glucose

Topics

• Diabetes Mellitus, Type 2 (metabolism, physiopathology)
• Glucose (metabolism)
• Heart (physiopathology)
• Humans
• Insulin Resistance
• Liver (chemistry)
• Magnetic Resonance Imaging
• Magnetic Resonance Spectroscopy
• Middle Aged
• Myocardium (metabolism)
• Phosphates (metabolism)
• Positron-Emission Tomography
• Triglycerides (analysis)
• Ventricular Function, Left (physiology)