| Popis: |
Obese subjects consistently demonstrate increased DNA damage compared to healthy individuals. Besides excess body weight, obesity is associated with comorbidities such as cardiovascular disease, type 2 diabetes mellitus, hypertension and non-alcoholic fatty liver disease, all of which are connected with oxidative stress. Increased oxidative stress could damage cellular macromolecules including DNA, with genomic instability as one of the driving forces for carcinogenesis. Although conservative weight loss regimens demonstrated beneficiary influence on DNA damage reduction, little is known whether a similar effect can be achieved with a more extensive weight loss using more restrictive calorie reduction diets, so the predictions for human population is mostly based on in vitroand animal model studies. The aim of this preliminary study was to examine the impact of a 3-week calorie reduction diet of only 500 kcal in persons with a body mass index of ≥ 35 kg/m2, without any known comorbidity and therapy, on genomic stability using cytochalasin B-blocked micronucleus assay, alkaline comet assay and modified alkaline comet assay for oxidative DNA damage measurement. Fresh whole blood samples were taken before and after the three weeks hospital treatment with the strict diet regime. The results of this preliminary study on 10 volunteers demonstrated reduced volunteers body weight, reduced levels of DNA damage in alkaline comet assay and in oxidative DNA damage. There was a slight reduction in frequency of micronuclei (parameter of whole chromosome loss or partial chromosome loss), while the frequency of nuclear buds (parameter of gene amplification) and nucleoplasmic bridges (parameter of dicentric chromosomes) remained the same. There was also an increase in the proliferation index and reduction in number of apoptosis. The results indicated a beneficiary effect of this strict calorie reduction diet and should be repeated on a higher number of participants. |
