Relations of angiotensin-(1-7) with hemodynamic and cardiac structural and functional parameters in patients with hypertension and type 2 diabetes

Background. The angiotensin-(1-7) is a new component of the renin-angiotensin system, the product of the degradation of angiotensin II and its functional antagonist, but its role in hypertension with type 2 diabetes (T2D) is not clear. The aim of the study was to investigate the levels of angiotensin-(1-7) in patients with hypertension and T2D and determine its relations to hemodynamic and cardiac structural and functional parameters. Material and methods. We examined 70 patients with hypertension and T2D. Investigation protocol included physical examination, standard transthoracic echocardiography and determination of the angiotensin-(1-7) blood levels by ELISA. Control group consisted of 16 healthy volunteers. Results. The angiotensin-(1-7) levels in observed patients were significantly lower than in volunteers [105.51 (89.13;121.17) ng/L vs. 132.75 (125.06; 142.87) ng/L, p < 0.001]. The levels of the angiotensin-(1-7) significantly negatively correlated with duration of hypertension (r = –0.29, p < 0.05), systolic blood pressure (BP) (r = –0.38, p < 0.05), diastolic BP (r = –0.36, p < 0.01), average BP (r = –0.32, p < 0.01), left ventricular (LV) internal dimension at end-diastole (r = –0.37, p < 0.01), LV mass (r = –0.40, p < 0.001), LV mass index (r = –0.41, p < 0.001). In patients with LV hypertrophy, angiotensin-(1-7) levels were significantly lower than in patients without LV hypertrophy [101.9 (88.2; 117.7) ng/L vs. 129.3 (117.5; 136.8) ng/L, p < 0.01] and in patients with diastolic LV dysfunction — lower than in the patients with normal diastolic function [101.1 (87.9; 116.6) ng/L vs. 121.1 (105.5; 128.9) ng/L, p < 0.01]. Conclusions. The angiotensin-(1-7) can be considered as an important pathogenetic factor in the development of hypertension with T2D, a BP regulator and a cardioprotective agent that prevents the development of remodeling and diastolic dysfunction of the LV.