Long-Term Effects of Caloric Restriction or Exercise on DNA and RNA Oxidation Levels in White Blood Cells and Urine in Humans

Abstract

Excessive adiposity is associated with increased oxidative stress and accelerated aging. Weight loss induced by negative energy balance reduces markers of oxidation in experimental animals and humans. The long-term effects of weight loss induced by calorie restriction or increased energy expenditure induced by exercise on measures of oxidative stress and damage have not been studied in humans. The objective of the present study was to compare the effects of 20% caloric restriction or 20% exercise alone over 1 year on oxidative damage to DNA and RNA, as assessed through white blood cell and urine analyses. Eighteen men and women aged 50 to 60 years with a body mass index (BMI) between 23.5 to 29.9 kg/m2 were assigned to one of two conditions — 20% CR (n = 9) or 20% EX (n = 9) — which was designed to produce an identical energy deficit through increased energy expenditure. Compared to baseline, both interventions significantly reduced oxidative damage to both DNA (48.5% and 49.6% reduction for the CR and EX groups, respectively) and RNA (35.7% and 52.1% reduction for the CR and EX groups, respectively) measured in white blood cells. However, urinary levels of DNA and RNA oxidation products did not differ from baseline values following either 12-month intervention program. Data from the present study provide evidence that negative energy balances induced through either CR or EX result in substantial and similar improvements in markers of DNA and RNA damage to white blood cells, potentially by reducing systemic oxidative stress.

Diet-Induced Weight Loss Reduces DNA Damage and Cardiometabolic Risk Factors in Overweight/Obese Women with Polycystic Ovary Syndrome

“…In this sense, our results support the hypothesis that a proper and balanced diet (even with a discrete loss of weight) exerts a protection role on genome, by enhancing DNA repair and/or preventing cell death and mutations as shown in previous studies [24,[39][40][41] .…”

Insulin signaling and life span

“…Therefore, CRAN may extend the life span by decreasing the pro-inflammatory state: This condition attenuates insulin resistance and, concomitantly, decreases both metabolic disturbances and CVD. In humans, longterm CRAN not only decreases total and free IGF-1 concentrations but also reduces oxidative damage to both DNA and RNA measured in white blood cells [59]. In terms of cardiovascular health, CRAN has powerful protective effects against atherosclerosis.…”

Dietary restriction and Sirtuin 1 in metabolic health: connections and divergences

“…In several studies conducted in overweight human subjects, DR has been shown to improve a number of health outcomes, including a reduction in several cardiac risk factors (13)(14)(15) , an improvement in insulin-sensitivity (16) , and enhanced mitochondrial function (17) . Additionally, prolonged DR has also been found to reduce oxidative damage (18)(19)(20) . This way, findings of initial human clinical trials appear to support the promise of DR raised by animal studies, at least in overweight adults.…”