Methodology

The model of obese female Zucker rats (ZDF) before and after ovariectomy will be used. Plasma samples from diabetic patients of different reproductive ages will be evaluated.

Ovariectomy-induced menopause model

After reaching 16 weeks, female ZDF rats will undergo bilateral ovariectomy via a midline incision, blinded animals will undergo the entire surgical procedure except for removal of the ovaries

Blood pressure and heart rate

determined by the tail cuff method in rats previously trained for measurement

Basic parameters of glucose metabolism

determination of blood glucose and insulin levels will be monitored before and after meals/ oral glucose tolerance test, ELISA

Basic parameters of lipid metabolism and parameters of renal and cardiac damage in plasma

determination of triglycerides, total cholesterol, HDL and LDL, cholesterol, non-esterified fatty acids, creatinine, urea, uric acid, albumin, aspartate aminotransferase, etc./ biochemical analyzer

Pro-inflammatory and anti-inflammatory factors, adipocytokines and vasodilating factors in plasma

determination of various adipocytokines, inflammatory and vasodilating factors (hsCRP, MCP-1, TNFα, IL-6, leptin, chemerin, cGMP, etc.)/ELISA

H2S level

determination of H2S concentration in plasma and vascular tissue/methylene blue method, H2S sensor based on electrode technology

NO-synthase activity

determination of NO-synthase activity in cardiovascular tissues/method of conversion of labeled [3H]-L-arginine to L-citrulline using a scintillation analyzer

Quantification of angiotensins in plasma

comprehensive biochemical characterization of circulating components of the renin angiotensin system in cooperation with Attoquant Diagnostics/RAS-Fingerprint™

Measurement of protease activities and concentrations

determination of ACE2 activity and sACE2 concentration, ADAM17 and TMPRSS2 in plasma and tissue samples/fluorometry, ELISA.

Functional studies

integrated blood pressure response in vivo after acute application of vasopressor and vasodepressor agents acting on individual signaling pathways/ blood pressure sensor inserted into a. carotis

changes in blood flow in a vessel supplying a selected area (e.g. renal artery)/perivascular flow system

vasoactive responses of isolated arteries to assess vascular damage – endothelial dysfunction, contractility disorder and perivascular adipose tissue/tensometry, myography

Genomic and proteomic analysis

analysis of the arterial wall and perivascular adipose tissue – analysis of gene and protein expression of vasoactive and inflammatory factors, lipid metabolism factors as well as other factors involved in various signaling pathways/RT qPCR, Western blot analysis, visualization using immunofluorescence

Oxidative stress

measurement of superoxide production in aortic and left ventricular tissues/lucigenin-enhanced chemiluminescence

determination of conjugated dienes/spectrophotometry

Patient samples

plasma samples taken from randomly selected patients II. Internal Medicine Clinic, University Hospital in Bratislava, main criterion – diagnosed type II diabetes

determination of plasma levels of selected parameters (H2S level, lipid profile, inflammatory factors, markers of heart and kidney damage, etc.) in diabetic pre- and postmenopausal patients