The Effects of Bariatric Surgery on Kidney Oxygenation in Obese Adults With Type 2 Diabetes and Hyperfiltration

Group 1: T2DM patients with obesity and hyperfiltration Inclusion criteria: * Caucasian; man or women aged ≥18 years and \<55 years. Females must be pre-menopausal * Type 2 diabetes mellitus or pre-diabetes with HbA1c ≥45mmol/mol and \<10% (\<94mmol/mol) * BMI ≥35 * eGFR\>90 ml/min calculated as by CKD-EPI * Provision of signed and dated, written informed consent prior to any study specific procedures * Hypertension should be controlled, i.e., ≤ 155/95 mmHg. * Scheduled for gastric bypass or gastric sleeve Exclusion criteria: * Diagnosis of type 1 diabetes mellitus * Post-menopausal females (defined as no menses \>1 year and follicle stimulating hormone (FSH) \>31 U/L) * Cardiovascular disease event in the last 6 months prior to enrollment as assessed by the investigator, including: myocardial infarction, cardiac surgery or revascularization (CABG/PTCA), unstable angina, heart failure, transient ischemic attack (TIA) or significant cerebrovascular disease, unstable or previously undiagnosed arrhythmia. * Chronic use of sodium-glucose transporter-2 inhibitors, oral glucocorticoids, non-steroidal anti-inflammatory drugs (NSAIDs), immune suppressants, chemotherapeutics, antipsychotics, tricyclic antidepressants (TCAs), diuretics, or monoamine oxidase inhibitors. * Current urinary tract infection or active nephritis * History of allergy/hypersensitivity to any of the test agents * Contra-indication for MRI * Any other condition that prevents participation as judged by investigator. Group 2: Non-diabetic lean controls Inclusion criteria: * Caucasian; male of female aged ≥18 years and \<40 years. Females must be pre-menopausal * Provision of signed and dated, written informed consent prior to any study specific procedures. * Normal glucose tolerance confirmed by HbA1c * No hypertension * BMI ≥18,5 and \<25 kg/m² Exclusion criteria: * Macro-albuminuria (defined as UACR\>30 mg/mmol) * Post-menopausal females (defined as no menses \>1 year and follicle stimulating hormone (FSH) \>31 U/L)\*. * Cardiovascular disease event in the last 6 months prior to enrollment as assessed by the investigator, including: myocardial infarction, cardiac surgery or revascularization (CABG/PTCA), unstable angina, heart failure, transient ischemic attack (TIA) or significant cerebrovascular disease, unstable or previously undiagnosed arrhythmia. * Chronic use of renin-angiotensin-system blockers, sodium-glucose transporter-2 inhibitors, GLP-1 receptor agonists, DPP-4 inhibitors, oral glucocorticoids, non-steroidal anti-inflammatory drugs (NSAIDs), immune suppressants, chemotherapeutics, antipsychotics, tricyclic antidepressants (TCAs), diuretics ormonoamine oxidase inhibitors. * Current urinary tract infection or active nephritis * History of allergy/hypersensitivity to any of the test agents * Contra-indication for MRI