Renal hemodynamics, i.e. glomerular filtration rate (GFR, ml/min) and effective renal plasma flow (ERPF, ml/min) will be measured by the gold-standard inulin- and para-aminohippurate (PAH) clearance methods, respectively, during both euglycemic- and hyperglycemic clamp; renal tubular function will be measured by 24-hour urine sodium, potassium, chloride, calcium, magnesium, phosphate and urea and glucose; markers of renal damage will include urinary albumin excretion, neutrophil gelatinase-associated lipocalin and kidney injury molecule-1; blood pressure will be measured using an automated oscillometric blood pressure device (Dinamap®); body anthropometrics, including body weight, height, body-mass index and waist circumference, and body fat contents (by bio-impedance analysis) will be measured; blood samples will be obtained to determine glycemic variables, lipids and markers of inflammation; systemic hemodynamic variables (including stroke volume, cardiac output and total peripheral resistance) will be measured by continuous beat-to-beat hemodynamic monitor (NexFin®); heart rate will be determined by oscillometric blood pressure device; microvascular function will be measured by capillary videomicroscopy and Laser Doppler; arterial stiffness will be assessed by applanation tonometry, (SphygmoCor®); additional urine, blood and feces will be collected for conditional determination of various markers of renal damage/function, inflammation, oxidative stress and (cardiovascular)-biomarkers and DNA; cardiac autonomous nervous system (CANS) will be measured by electrocardiography and NexFin®; insulin sensitivity will be measured by glucose infusion during the euglycemic clamp (M-value); beta-cell function will be measured by quantification of insulin secretion during the hyperglycemic clamp.