Control of Renal Oxygen Consumption, Mitochondrial Dysfunction, and Insulin Resistance

Study Overview
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Brief Summary
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Type 1 diabetes (T1D) is a complex metabolic disorder with many pathophysiological disturbances including insulin resistance (IR) and mitochondrial dysfunction which are causally related to the development of diabetic kidney disease (DKD) and which contribute to reduced life expectancy. Renal hypoxia, stemming from a potential metabolic mismatch between increased renal energy expenditure and impaired substrate utilization, is increasingly proposed as a unifying early pathway in the development of DKD. By examining the interplay between factors responsible for increased renal adenosine triphosphate (ATP) consumption and decreased ATP generation in young adults with and without T1D, this study hopes to identify novel therapeutic targets to impede the development of DKD in future trials. The investigators propose to address the specific aims in a cross-sectional study with 30 adults with T1D and 20 controls without a diagnosis of diabetes. For this protocol, participants will complete a one day study visit at Children's Hospital Colorado. Patients will undergo a Dual-energy X-Ray Absorptiometry (DXA) scan to assess body composition, renal Magnetic Resonance Imaging (MRI) to quantify renal oxygenation and perfusion, and a Positron Emission Tomography/Computed Tomography (PET/CT) scan to quantify renal O2 consumption. After the PET and MRI, participants will undergo a hyperinsulinemic-euglycemic clamp to quantify insulin sensitivity. Glomerular Filtration Rate (GFR) and Effective Renal Plasma Flow (ERPF) will be measured by iohexol and PAH clearances during the hyperinsulinemic-euglycemic clamp. To further investigate the mechanisms of renal damage in T1D, two optional procedures are included in the study: 1) kidney biopsy procedure and 2) induction of induced pluripotent stem cells (iPSCs) to assess morphometrics and genetic expression of renal tissue.

Official Title
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CROCODILE Study: Control of Renal Oxygen Consumption, Mitochondrial Dysfunction, and Insulin Resistance

Conditions
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Diabetic Kidney Disease, Type 1 Diabetes, Diabetes, Diabetes Mellitus, Diabetes Complications, Diabetic Nephropathies, Type1diabetes, Diabetes, Autoimmune, Autoimmune Diabetes, Juvenile Diabetes, Type 1 Diabetes Mellitus

Intervention / Treatment
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* Drug: Aminohippurate Sodium Inj 20%
* Drug: Iohexol Inj 300 milligrams/milliliter (mg/ml)
* Radiation: PET/CT Scan
* Procedure: Renal Biopsy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria -- Type 1 Diabetes: Antibody positive Type 1 Diabetes with duration > 5 years BMI between 18.5 and 30 kg/m2 Weight < 350 lbs HbA1c < 11% Hemoglobin >= 12 g/dl Exclusion Criteria -- Type 1 Diabetes: Recent diagnosis (within 3 months) of Diabetic Ketoacidosis (DKA) Severe illness Pregnancy, nursing Anemia Allergy to shellfish or iodine Claustrophobia or implantable metal devices (MRI contraindications) High blood pressure (greater than 130/80 mm Hg) Elevated Urine Albumin-to-Creatinine Ratio (UACR) (>30 mg/g) or estimated Glomerular Filtration Rate (eGFR) <90 ml/min/1.73 m2 Taking ACE inhibitors (ACEis), Angiotensin receptor blockers (ARBs), diuretics, Sodium Glucose Transporter (SGLT) 1/2 blockers Inclusion Criteria -- Healthy Controls: No diagnosis of Type 1 or Type 2 Diabetes BMI between 18.5 and 30 kg/m2 Weight < 350 lbs HbA1c < 11% Hemoglobin >= 12 g/dl Exclusion Criteria -- Healthy Controls: Severe illness Pregnancy, nursing Anemia Allergy to shellfish or iodine Claustrophobia or implantable metal devices (MRI contraindications) High blood pressure (greater than 130/80 mm Hg) Elevated UACR (>30 mg/g) or eGFR <90 ml/min/1.73 m2 Taking ACE inhibitors (ACEis), Angiotensin receptor blockers (ARBs), diuretics, SGLT 1/2 blockers Additional exclusion criteria for participants undergoing optional kidney biopsy: Evidence of bleeding disorder or complications from bleeding Use of aspirin, NSAIDS or other blood thinner that cannot be safely stopped for a sufficient time period before and after the biopsy so as to add no additional risk of bleeding Blood urea nitrogen (BUN) > 80 gm/dL INR > 1.4 PTT > 35 seconds Hemoglobin (Hgb) < 10 mg/dL Platelet count < 100,000 / µL Uncontrolled or difficult to control hypertension (> 150/90 mmHg at the day of biopsy) eGFR < 40 mL/min/1.73m2 Single kidney (either by history, documented by prior imaging or ultrasound performed prior to the biopsy) > 2 cm discrepancy between left and right kidney sizes based on largest longitudinal diameter determined by ultrasound performed prior to the biopsy. Kidney size: One or both kidneys < 9 cm Hydronephrosis or other important renal ultrasound findings such as significant stone disease Any evidence of a current urinary tract infection as indicated on day of biopsy Clinical evidence of non-diabetic renal disease Positive urine pregnancy test or pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Type 1 Diabetes<br>All participants will undergo DXA scan, magnetic resonance imaging (MRI) studies of the kidneys, PET/CT using 11-C acetate to measure renal oxygen consumption, hyperinsulinemic-euglycemic clamp to quantify insulin sensitivity, and renal clearance testing using iohexol and para-aminohippurate (PAH) to quantify glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). | Drug: Aminohippurate Sodium Inj 20%<br>* Diagnostic aid/agent used to measure effective renal plasma flow (ERPF)<br>* Other names: Aminohippuric acid;Drug: Iohexol Inj 300 milligrams/milliliter (mg/ml)<br>* Diagnostic aid/agent used to measure glomerular filtration rate (GFR)<br>* Other names: omnipaque 300;Radiation: PET/CT Scan<br>* Imaging used to visualize the kidneys and quantify renal metabolic activity<br>Procedure: Renal Biopsy<br>* Minimally invasive outpatient procedure to obtain renal tissue after ultrasound visualization.<br>|
| Healthy Controls<br>All participants will undergo DXA scan, magnetic resonance imaging (MRI) studies of the kidneys, PET/CT using 11-C acetate to measure renal oxygen consumption, hyperinsulinemic-euglycemic clamp to quantify insulin sensitivity, and renal clearance testing using iohexol and para-aminohippurate (PAH) to quantify glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). | Drug: Aminohippurate Sodium Inj 20%<br>* Diagnostic aid/agent used to measure effective renal plasma flow (ERPF)<br>* Other names: Aminohippuric acid;Drug: Iohexol Inj 300 milligrams/milliliter (mg/ml)<br>* Diagnostic aid/agent used to measure glomerular filtration rate (GFR)<br>* Other names: omnipaque 300;Radiation: PET/CT Scan<br>* Imaging used to visualize the kidneys and quantify renal metabolic activity<br>Procedure: Renal Biopsy<br>* Minimally invasive outpatient procedure to obtain renal tissue after ultrasound visualization.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Renal Oxygenation | Blood oxygen level dependent (BOLD) MRI | 30 minutes | 
| Renal Perfusion | Arterial Spin Labeling (ASL) MRI | 30 minutes | 
| Renal Oxygen Consumption | 11-C Acetate PET/CT | 30 minutes | 
| Insulin Sensitivity | Hyperinsulinemic-Euglycemic Clamp | 4.5 hours | 
| Mitochondrial Function | Blood draw for mitochondrial DNA copy number | 5 minutes | 
| Mitochondrial Function | Blood draw for untargeted metabolite assessment of the tricyclic acid (TCA) cycle | 5 minutes | 
| Mitochondrial Function | Blood draw for targeted assessment and quantification of glucose oxidation using an established metabolite panel | 5 minutes | 
| Mitochondrial Function | Blood draw for untargeted metabolite assessment of Free Fatty Acid (FFA) oxidation | 5 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Glomerular Filtration Rate (GFR) | Iohexol Clearance Study | 3 hours | 
| Effective Renal Plasma Flow (ERPF) | PAH Clearance Study | 2.5 hours | 
| Renin-Angiotensin-Aldosterone-System Activity | Blood draw for Plasma Renin levels | 5 minutes | 
| Renin-Angiotensin-Aldosterone-System Activity | Blood draw for Angiotensin II levels | 5 minutes | 
| Renin-Angiotensin-Aldosterone-System Activity | Blood draw for Copeptin levels | 5 minutes | 
| Kidney Injury Biomarkers | Blood draw for Tyrosine Lysine Leucine-40 (YKL-40) levels | 5 minutes | 
| Kidney Injury Biomarkers | Blood draw for Neutrophil gelatinase-associated lipocalin (NGAL) levels | 5 minutes | 
| Kidney Injury Biomarkers | Blood draw for Kidney Injury Marker 1 (KIM-1) levels | 5 minutes | 
| Kidney Injury Biomarkers | Blood draw for Interleukin-18 (IL-18) levels | 5 minutes | 
| Kidney Injury Biomarkers | Blood draw for Tumor Necrosis Factor Receptor 1/2 (TNF-R 1/2) levels | 5 minutes |