Patient description: The patient is a 24-year-old man who has had type 1 diabetes for 11 years. He presents to the emergency room with hyperglycemia and concern for possible diabetic ketoacidosis after not taking his insulin for 3 days. The patient reports that he is currently homeless and has lost his supply of insulin, syringes, glucometer, and glucose testing supplies. The patient states that at the time of his initial diagnosis with type 1 diabetes he was hospitalized with a glucose value >1000 mg/dL. At the time, he was experiencing polyuria, polydipsia, and polyphagia. He reports that he has been on insulin since the time of his diagnosis, and he has never been prescribed oral agents for diabetes management. Most recently, he has been using insulin glargine 55 units once daily, and insulin aspart sliding scale 3 times daily. The patient has had previous episodes of diabetic ketoacidosis, for which he was hospitalized. With this episode of hyperglycemia, he is not experiencing any nausea, vomiting, or abdominal discomfort, and he appears well. His lab studies showed: A1c: 11.3% Creatinine: 0.9 mg/dL with eGFR >60 mL/min Aspartate aminotransferase (AST): 17 U/L Alanine aminotransferase (ALT): 14 U/L Beta-hydroxybutyrate: 0.1 mmol/L Bicarbonate: 25 mEq/L Anion

Clinical trial eligibility criteria: eligible ages (years): 21.0-999.0,  Type 2 Diabetes Type 2 Diabetes 1. Adult age 21 or older 2. If on 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase reductase therapy, must be on a stable dose for at least 6 weeks prior to enrollment 3. Diagnosis of type 2 diabetes by a physician as defined by the American Diabetes Association standard 1) Fasting Plasma glucose at or above 126 mg/dL 2) a two-hour value in an oral glucose tolerance test at or above 200 mg/dL, or 3) a random plasma glucose concentration 200 mg/dL in the presence of symptoms, or 4) glycosylated hemoglobin greater than or equal to 6.5%. Score of < 4 using the Gold method for assessing hypoglycemia awareness for Healthy subjects 1. Adult age 21 or older 2. No evidence of metabolic syndrome or diabetes, hypertension (BP≥140/90), or high cholesterol (LDL≥160) at the time of screen  History of stroke, peripheral arterial disease, or coronary artery disease (as defined by the presence of at least one coronary stenosis ≥ 40% on angiography or by confirmed history of myocardial infarction by standard criteria) 2. Evidence of other evident major illness including chronic renal insufficiency(plasma creatinine > 1.4 for women or 1.5 for men), liver disease (aspartate aminotransferase or alanine aminotransferase greater than 2.5 x normal), and cancer currently undergoing therapy or had therapy for cancer within 1 year of enrollment. 3. Pregnancy as determine by urinary pregnancy test 4. Subjects on warfarin, oral anti-thrombin inhibitors, or thienopyridines 5. Subjects who have had changes to dosing of thiazolidinedione, dipeptidyl peptidase-4 (DPP-4) inhibitor, or metformin therapy within 6 weeks of enrollment. 6. Failed Allen's test in both arms unable to safely place an arterial line 7. Glucose reading of < 50 mg/dL and/or episodes of symptomatic hypoglycemia requiring the assistance of another person for recovery in the 2 years prior to enrollment. 8. History of hypoglycemic convulsions 9. Current fluoxetine therapy (known to interfere with neuroendocrine response to hypoglycemia) 10. Glycosylated hemoglobin over 8.5% 11. On aldosterone antagonist therapy at the time of enrollment 12. On insulin therapy at the time of screening. 13. History of allergy to local anesthetic injection like lidocaine. 14. Age below 21 for Healthy Subjects: 1. Meet any of the for diabetic or metabolic syndrome group Meet for type 2 diabetes or metabolic syndrome 2. On medication for cholesterol or blood pressure. 3. History of allergy to local anesthetic injection like lidocaine