Low fructose and low salt diets increase mitochondrial DNA in white blood cells of overweight subjects

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 oxygen 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.