Increased oxidative damage to lipids and DNA in overweight and obese patients
Janusz Szosland1, Agnieszka Kokoszko1,3, Krzysztof Zasada1,3, Jan Stepniak1, Andrzej Lewinski2,3 & Malgorzata Karbownik-Lewinska1,3
Introduction: Obesity does constitute one of the most common modifiable risk factors for cancer. The process of cancerogenesis is associated with the enhanced oxidative stress. Lipid peroxidation (LPO), resulting from oxidative damage to membrane lipids, as well as oxidative damage to DNA, are the most frequently examined processes to evaluate oxidative damage to macromolecules.
Aim: The aim of the study was to evaluate the level of oxidative damage to membrane lipids and nuclear DNA in overweight and obese adult patients.
Patients and methods: Serum concentrations of malondialdehyde+4-hydroxyalkenals (MDA+4-HDA), as an index of membrane LPO, and 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo) in peripheral blood leukocytes, as an index of oxidative damage to nuclear DNA, were measured in fifty eight (58) overweight and obese adult patients (BMI ≥ 25 kg/m2), and in twenty (20) healthy volunteers (BMI <25 kg/m2), matched for sex and age. Clinical and laboratory parameters, which are frequently affected by obesity, were also measured in the study.
Results: Both LPO and 8-oxodGuo levels increased in overweight and obese patients and further increase of both of them was observed with the increasing body mass and BMI. Expectedly, positive correlation between oxidative damage to membrane lipids and nuclear DNA was also found. Additionally, LPO level correlated positively with waist/hip ratio, C-reactive protein, ferritin and glucose concentrations, whereas 8-oxodGuo correlated positively with triglyceride concentration and negatively with iron concentration. BMI did constitute the only independent predictor of increased oxidative damage to membrane lipids in overweight and obese patients.
Conclusions: Overweight and obesity in adults are associated with increased oxidative damage to membrane lipids and nuclear DNA. BMI constitutes the independent risk factor for oxidative damage to macromolecules. Enhanced oxidative stress in obesity may contribute to increased risk of cancer.