The effect of diabetes mellitus under tumor growth on respiratory function and free radical processes in heart cell mitochondria in rats

Abstract

The aim is to study the effect of comorbid pathology, namely, diabetes mellitus, on free radical oxidation in the mitochondria in the heart cells in female rats with experimental Guerin carcinoma.

Materials and methods

The study has been performed in female outbred rats (n=32) weighed 180-220 g. The animals have been randomly assigned to the following experimental groups: intact group (n=8), control group with diabetes (n=8), comparison group (n=8) to include rats with standard subcutaneous transplantation of Guerin's carcinoma, and the main group (n=8) to cover rats which were first reproduced with diabetes and which after 1 week of persistent hyperglycemia were transplanted with Guerin's carcinoma. In the samples of the heart mitochondria, the following concentrations were measured by the ELISA method: cytochrome C (ng/mg protein) (Bioscience, Austria), 8-hydroxy-2'-deoxyguanosine (8-OHdG) (ng/mg protein); malondialdehyde (MDA) (mmol/mg protein); the Statistica 10.0 software was used.

Results

In diabetes mellitus (control group), an increase in 8-OHdG by 6.3 times, MDA by 1.9 times (p<0.05), and a decrease in cytochrome C by 1.5 times (p<0.05) were found in the mitochondria in the heart cells compared to the values in the intact group. The effect of Guerin's carcinoma on the mitochondria of heart cells was expressed only as a change in the MDA level, which exceeded the intact level by 1.8 times (p<0.05). The combination of two pathological processes in the animal's body, namely, diabetes mellitus and the malignant tumor, caused an increase in the level of 8-OHdG by 14 times, MDA by 1.7 times (p<0.05) and a decrease in cytochrome C by 1.46 times (p<0.05).

Conclusions

It has been found that the destabilization of the respiratory chain in mitochondria in female rats’ heart cells occurs as a result of the activation of free radical oxidation processes under the influence of diabetes mellitus, both in its independent variant and linked with the tumor process.

Imprint

Elena M. Frantsiyants, Irina V. Neskubina, Alla I. Shikhlyarova, Natalia D. Cheryarina, Irina V. Kaplieva, Valeria A. Bandovkina, Lidia K. Trepitaki, Lyudmila A. Nemashkalova, Irina B. Lysenko, Polina S. Kachesova, Elena A. Sheiko, Maria I. Morozova, Inga M. Kotieva. The effect of diabetes mellitus under tumor growth on respiratory function and free radical processes in heart cell mitochondria in rats. Cardiometry; Issue 18; May 2021; p.50-55; DOI: 10.18137/cardiometry.2021.18.5055; Available from: http://www.cardiometry.net/issues/no18-may-2021/effect-of-diabetes-mellitus