7/31/2009. G.Y. Prince Used Cars 10 am Los Angelos, CA Mullholland Drive..later that day. Would you buy a car without taking it for a spin first?

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1 7/31/29 My Anna will love it! Who needs a test drive? Or a Warranty? It looked great in the lot! Do mean to say that you never actually test drove the car? G.Y. Prince Used Cars 1 am Los Angelos, CA Mullholland Drive..later that day Would you buy a car without taking it for a spin first? Delorean looked good in the lot... By analogy. No!!! It could look great in the lot but you have to test it when its parts are all working. Can the metabolic function of a patient or experimental subject be fully understood without testing it under conditions that challenge the metabolic processes of the body? 1

2 7/31/29 AT is a Valuable Diagnostic Tool Lactate mm 1 1 Heart Disease Onset of lactic acidosis Athlete Non-Invasive Measurement of Work Capacity in People Rest Period 1 1 (watts) 2 2 as a tool to Diagnosis Cardiac Function For the same reason exercise is valuable for diagnosis in patients, it is valuable for provoking phenotypes and dysregulation in experimental models of metabolic disease. increases metabolic demands and amplifies signals. 2

3 7/31/29 Chronically Catheterized, Conscious Mouse Model Protocol Sample Insulin Sample Saline -6 3 min Infusate Infusate Acclimation Sd Sedentary or 2DG Bolus Excise Tissues Vein Artery Vein Artery Treadmill ptf 22 Methods for Measuring Uptake in vivo Sedentary and Exercising Mice 2DGP tissue (t) R g = AUC 2DG plasma Plasma 2DG (dpm l -1 ) Bolus plasma 3 2 Uptake (μmol 1g -1 min-1 ) 1 Gastrocnemius WT GLUT4 +/- HK +/- Sedentary Time (min) ptf 22 3

4 7/31/29 Gastrocnemius R g versus HK II in Mice Soleus R g versus HK II in Mice -Stimulated Basal 12 -Stimulated Basal Gastrocnemius R g (µmol 1g -1 min -1 ) Soleus R g (μmol 1g -1 min -1 ) Relative HK II Activity Relative HK II Activity Tolerance of C7Bl6 Mice to Treadmill Endurance Time min HK +/- WT HK Tg Fractional Uptake of 2-Deoxyglucose 4 Uptake (ml 1g -1 min-1 ) 3 Fractional Uptake of 2-Deoxyglucose Uptake by in Sedentary and d Mice Sed Ex Wild Type HK II overexpression Gastrocnemius Sedentary GLUT4 Protein (Arbitrary Units) 4

5 7/31/29 Saline-infused and Insulin-clamped C7Bl6 Mice Sedentary and Exercising C7Bl6 Mice R g (μmol 1g -1 min -1 ) Chow Fed 1 Gastroc 1 1 SVL 1 WT HK Tg High Fat Fed Saline-infused Insulin -clamped WT HK Tg R g 2 (μmol 1g -1 min -1 ) Chow Fed 4 Gastroc 2 SVL 1 WT HKII TG High Fat Fed Sedentary WT HKII TG PDE Inhibition and Vascular Conductance Hypothesis Increasing conductance of the muscle vasculature will prevent insulin resistance in high fat fed mice. Nitric Oxide Natriuretic Peptides & Guanylins sgc pgc PDE cgmp GMP PKG Vascular Smooth Cell vessel relaxation PDE Inhibitor

6 7/31/29 Ohm s Law and Insulin Resistance Influx G a G e G i WT Protocol: Sildenafil/L-arginine in the Prevention of Diet-Induced Insulin Resistance 4 wk old male C7BL/6J mice fed a high fat diet 13 wks PDE(-) Sildenafil (12 µg/g/day) and L-arginine (1 µg/g/day) n=13 Vehicle (ph matched saline) n=14 Sildenafil was used to inhibit PDE activity and increase vascular conductance Insulin Clamp after 13 wk of Sildenafil/Arginine Ayala et al. Diabetes 6: Arterial mg dl -1 Insulin clamp in the High Fat Fed Mouse 2 Vehicle 2 1 Sildenafil/ 1 L-arginine Insulin Clamp Vehicle Sildenafil/ 6 L-arginine Infusion 4 3 mg kg-1 min P<. vs. Saline Time (min) Ayala et al. Diabetes 6: Index of Uptake during an Insulin Clamp in High Fat Fed Mice Uptake µmol 1 g tissue-1 min Soleus Gastrocnemius Vehicle Sildenafil/L-arginine SVL Fueger et al. Diabetes 3:36-14, 24. 6

7 7/31/29 PDE Inhibition in a Mouse Model of Dietary Insulin Resistance Inhibition of PDE using sildenafil prevents the insulin resistance associated with high fat feeding. This effect occurs in the absence of improved insulin signaling through the PI3-kinase pathway. to Delineate Hormonal Control of Hepatic Production Maintaining 4 Grams of in the Carbohydrate Stores after an Overnight Fast Sedentary Stimulus Brain 4 ~4 Fat 1 4 Stimulus 7

8 7/31/29 Carbohydrate Stores after an Overnight Fast 1 hr of Carbohydrate Stores after an Overnight Fast 2 hr of Carbohydrate Stores after an Overnight Fast 3 hr of Carbohydrate Stores after an Overnight Fast 4 hr of !!! 4 8

9 7/31/29 Why don t we get hypoglycemic when we exercise? Endocrine and Sympathetic Nerve Response to 12 Glucagon 16 Utilization mg kg -1 min - 1 Hepatic Production mg kg -1 min - 1 Arterial Plasma mg dl Time (minutes) If the liver does not release more glucose during exercise... Hypoglycemia rapidly ensues Arterial Glucagon pg ml Arterial Catecholamines 2 pg ml -1 1 Norepinephrine Epinephrine Insulin Arterial Insulin µu ml -1 Time (min) A Minimal Overview of the Circulation Chronically-Catheterized Conscious Dog Model Investigator sees sees arterial head and upper extremities heart and lungs liver pancreas gut trunk and lower extremities portal vein venous 9

10 7/31/29 Protocols: Role of the -Induced Increase in Glucagon -12 min -4 1 as a Model to Study Glucagon Action 1 Simulated Glucagon Equilibration Basal Moderate Treadmill Arterial Glucagon 1 Somatostatin + [3-3 H]glucose + [U- 14 C]alanine Basal Intraportal Insulin -Simulated Intraportal Insulin pg/ml Basal Glucagon Saline Variable 1 Protocol A Basal Intraportal Glucagon Arterial Insulin µu/ml 1 Basal Glucagon Simulated Glucagon Protocol B Basal Intraportal Glucagon -Simulated Intraportal Glucagon Time (min) -12 min induced Increment in Glucagon Stimulates Hepatic Production -induced Increment in Glucagon Stimulates Gluconeogenesis from Alanine Arterial Plasma mg dl Simulated Glucagon Basal Glucagon Gluconeogenesis from Alanine (% Basal) Simulated Glucagon Basal Glucagon Hepatic Production mg kg-1 min Simulated Glucagon Basal Glucagon Intrahepatic Gluconeogenic Efficiency from Alanine (% Basal) Simulated Glucagon Basal Glucagon Time (min) 1

11 7/31/29 Why is Glucagon so Effective during? Brain Increase in Endogenous Production (mg kg -1 min-1 ) Comparison of the Effects of Similar Increases in Glucagon at Rest and during Autonomic Nerve Activity Ep i Pancreas Adrenal? Intestine Glycerol NEFA Adipose Working 2 1 Rest Glucagon Insulin IL6 RBP4 GNG Gly Amino Acids Lactate Amino Acids 4 Substrates Signals Why is Glucagon so Effective during? Brain Why is Glucagon so Effective during? Brain Autonomic Nerve Activity Autonomic Nerve Activity Ep i Adrenal? Intestine Body is in a Gluconeogenic Mode Adipose Working Ep i Adrenal? Intestine Body is in a Gluconeogenic Mode Adipose Working Pancreas Glycerol NEFA Pancreas Glycerol NEFA IL6 RBP4 Amino Acids Lactate Amino Acids IL6 RBP4 Amino Acids Lactate Amino Acids Glucagon Insulin GNG Gly 4 Substrates Signals Glucagon Insulin Effects are Potentiated by the Fall in Insulin GNG Gly 4 Substrates Signals 11

12 7/31/29 Why is Glucagon so Effective during? Brain Autonomic Nerve Activity Glucagon Ep i Pancreas Adrenal? Insulin Effects are Potentiated by the Fall in Insulin IL6 RBP4 GNG Gly Amino Acids Intestine Body is in a Gluconeogenic Mode Glycerol NEFA Lactate Amino Acids Adipose 4 Working Uptake Prevents Hyperglycemia Substrates Signals allows to be Studied in the Output Mode without Limitations that Exist in an Artificial Experimental Setting Role of Chronic Chronic may Play a Role in Preventing the Metabolic Syndrome or Reducing its Symptoms Unfortunately Compliance with Pro is Low. Many Pharmaceutical Treatments for Metabolic Syndrome attempt to do what Regular Physical Activity Does only without Complications Understanding how Regular Works may Provide for Better Drug Therapies that will Simulate Effects of in Otherwise Sedentary People 12