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According to the latest International Diabetes Federation 415 million people in the world have diabetes (DM) nowadays. Diastolic dysfunction (DD) is the characteristic of heart failure for patients with type 2 DM. Left ventricular (LV) DD is usually the result of impaired LV relaxation with or without reduced restoring forces and increased LV chamber stiffness. LV hypertrophy is the most potential and reversible marker of cardiovascular risk The macrophage cholesterol efflux is reduced for patients with type II DM, which is associated with the down-regulation of cholesterol 7-alpha-hydroxylase (CYP7A1) expression. CYP7A1 is a microsomal cytochrome P450 that catalyzes the first step in bile acid synthesis. Bile acid metabolism was reported to be involved in glucose metabolism homeostasis.
The objective of our study was the determination of relationship between single nucleotide polymorphism of -204A>C [rs 3808607] CУP7A1 promotor region and markers of DD for patients with type 2 DM and third stage of arterial hypertension (AH).
Patients were divided in two groups: 90 persons with type 2 DM and AH are involved in the first (I) group and 40 patients with AH are involved in the second (II) group. The persons were treated in Sumy City Clinical Hospital №1 during 2015-2016 years. The duration of DM was (10.6±1.7) years. The levels of systolic blood pressure were (148.4±2.16) mm, (140.7±1.2) mm, t=3.12, p‹0.01 and of diastolic - (99.4±2.5) mm of mercury, (88.5±2.2) mm of mercury, t=3,27, p‹0,01 respectively for I and II groups. Diastolic heart failure is the main characteristic of type 2 diabetes because of increased left ventricular myocardial mass (MM) and decreased E/A ratio.
The polymorphism of -204A>C [rs 3808607] CУP7A1 promotor region is defined with the help of polymerase chain reaction.
Echocardioscopy was done for all patients. We use formula recommended by the American Society of Echocardiography (ASE) for calculation of index of LVBM with definition of interventricular septum thickness, LV internal dimension; posterior wall thickness.
The levels of E/A were (0.89±0.04), (1.21±0.06), t=9.6, p<0.001 for patients from I and II groups. The LVBM were (330.5±0.56) g, (265.28±0.74)g, t=69.74, p<0,001 for patients with and without DM respectively. The indices of LVBM were (76.4±0.9) g/m2.7, (52.75±0.5) g/m2.7, t=22.97, p<0,001.
Three types of polymorphism of -204A>C [rs 3808607] CУP7A1 promotor region genotypes such as AA, AC, CC were defined. 43 patients with DM had AA, 7 – AC, 40 – CC genotypes.
The indices of LVBM were (70.25±0.4) g/m2.7, (73.4±0.9) g/m2.7, t=3.2, p<0.01; (82.4±3.8) g/m2.7, t=3.26, p<0.01 for persons with AA, AC, CC genotypes. The E/A were (0.93±0.02), (0.87±0.01), t=2.68, p<0.01, (0.82±0.04), t=2.46, p<0.05 for patients with AA, AC, CC respectively.
CC genotype of -204A>C [rs 3808607] CУP7A1 promotor region is the worse according to the prognosis for patients with type 2 DM and AH. Furthermore, it is associated with diastolic heart failure. The markers of DD such as indices of LVBM, E/A were severe for patients with type 2 DM and AH. The diastolic function is better for patients with AA genotype.