Type 2 diabetes is an inflammatory and metabolic disease, with significant increase in incidence over the past years. Besides hyperglycemia, type 2 diabetes is also characterised with dyslipidemia, which increases inflammatory state and oxidative stress of the body. Inflammatory response is dependent on expression of proinflammatory genes, while their expression is influenced by genetic changes in regulatory and coding parts of genes. Inflammation and oxidative stress are two factors, associated with accelerated shortening of telomeres. Telomeres are deoxyribonucleic acid–protein complexes located at the end of chromosomes with typical long tandem repeats of deoxyribonucleic acid. Their primal role is protection of the genome from deoxyribonucleic acid damage.
The goal of this master’s thesis was evaluation of the association of lipid state and accelerated shortening of telomere length of type 2 diabetes patients and evaluation of association of telomere length and genetic variability of inflammatory genes IL6, TNF, IL1B in these patients. We included 150 patients aged between 41 and 75 with type 2 diabetes and very high cardiovascular risk, as evaluated according to the 2016 European Society of Cardiology Guidelines on cardiovascular disease prevention and 2012 Slovenian adjustments. We determined, whether patients have elevated/normal levels of total cholesterol, elevated/normal levels of low-density lipoprotein cholesterol and triacylglycerols or decreased/normal levels of high-density lipoprotein cholesterol. For each patient, we had used modified Cawthon real-time polymerase chain reaction method to determine relative telomere length and competitive specific allele polymerase chain reaction, to determine gene polymorphism variants IL1B (rs16944), IL6 (rs1800795) and TNF (rs1800629). Using statistical analysis, we could not have proven the association between telomere length and lipid state of type 2 diabetes patients. We have adjusted the analysis regarding age, sex, statin treatment and the duration of diabetes, e.g. factors, that could additionally influence telomere length, but found no association. In our cohort of patients, the telomere length was not associated with polymorphisms of inflammatory genes IL6, TNF and IL1B. There was no association even after adjustment of age, sex, statin treatment and having elevated/normal values of total cholesterol. To get final elucidation of the scientific questions posted in this study, further research is required, preferably on larger group of patients.
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