Abstract
Objective:
To evaluate the effect of sodium and fructose restriction on mitochondrial DNA (mtDNA)
content and systemic oxidative stress in a sample of overweight and pre hypertensive
subjects.
Material/Methods:
Data and blood samples were collected from 36 overweight and pre hypertensive patients
randomly assigned to either an isocaloric (with respect to baseline) low sodium-fructose
diet or an isocaloric low sodium diet. Patients were followed for 8 weeks. We measured
mitochondrial DNA (mtDNA) content from peripheral blood white cells by Real-time PCR
and plasma malondialdehyde (MDA) and 2,4-dinitrophenylhydrazine (DNPH) as markers
of reactive oxigen species (ROS).
Results:
Compared to baseline, at week 8 there was a continued and significant increase in
mtDNA in both the low sodium diet group [2.4 vs. 13.1 (relative copy number), p<0.05]
and the low sodium diet-fructose group (1.9 vs. 147.2, p<0.05). By week 8 there was
a continued decrease in plasma DNPH levels in the low sodium diet group (4.6 vs. 2.6,
p<0.05) and in the low sodium diet-fructose group (5.8 vs. 2.2, p<0.05). No significant
differences were found with MDA.
Conclusion:
Our studies suggest that simple dietary measures such as reducing salt with or without
restricting fructose can increase mtDNA and improve markers of oxidative stress.
Key words
fructose - obesity - mitochondrial DNA (mtDNA) - reactive oxidative stress (ROS)