Endocrine Abstracts

Background: Arterial hypertension (AH) and type 2 diabetes mellitus (T2DM) are common non-infectious diseases with a high tendency to co-exist. Catestatin (CTS) and relaxin-2 have antihypertensive, cardioprotective and metabolic effects and can be considered as biomarkers of these diseases.

Objective: To evaluate plasma CTS and RLN-2 levels in hypertensive patients and to investigate their associations with parameters of glucose metabolism and their predictive potential for impaired glucose metabolism.

Materials and methods: The present study was performed in accordance with all ethical principles of the Declaration of Helsinki. The study protocol was approved by the local ethics committee. Each study participant signed a written informed consent prior to any protocol procedures. 106 patients with AH stage 2 and 30 healthy volunteers were enrolled in the study. 55 hypertensive patients had comorbid T2DM. The clinical examination, medical history data and blood samples were collected from all study subjects. Plasma CST levels were measured by an enzyme-linked immunosorbent assay (ELISA), using a commercial kit (E4996Hu, BT Lab, China), RLN-2 (E-EL-H1582, Elabscience, USA). The data are presented as a mean±S.D. or a median and interquartile range. Statistical significance was defined as P<0.05. Statistical data were analyzed using SPSS statistical software (SPSS 25.0 for Windows, IBM, Armonk, NY, USA).

Results: Patients with AH and T2DM had significantly decreased plasma CTS (4.47±1.16 vs 5.61±0.61; P<0.001) and RLN-2 levels (5.11 [4.97; 5.38] vs 6.71 [6.00; 7.14]; P<0.001) than hypertensive patients without T2DM. CTS and RLN-2 levels are correlated with parameters of glucose metabolism, particularly glucose (r=−0.45; P<0.001 and r=−0.637; P<0.001), HbA1c (r=−0.535; P<0.001 and r=−0.704, P<0.001), HOMA-IR (r=−0.481; P<0.001 and r=−0.394; P<0.001), and lipid profile parameters, especially triglycerides (r=−0.400; P<0.001 and r=0.480; P<0.001) and HDL-C (r=−0.481; P<0.001 and r=0.407; P<0.001). Univariate binary logistic regression established that CTS (0.175 [0.099 − 0.312; P<0.001) and RLN-2 (0.196 [0.095 − 0.405]; P<0.001) are significant predictors of impaired glucose metabolism, as well as insulin levels (1.118 [1.065 − 1.174]; P<0.001), HOMA-IR (2.020 [1.609 − 2.535]; P<0.001) and BMI (1.108 [1.002 − 1.224]; P=0.045).

Conclusions: In the present study, we determined the lower CTS and RLN-2 levels in patients with T2DM. Furthermore, we established that CTS and RLN-2 are significant predictors of impaired glucose metabolism. These findings suggest their possible diagnostic role as biomarkers of cardiometabolic diseases, especially AH with T2DM.