<Metformin's Effect on Glucagon-induced Glucose Production and Protein Metabolism. | RxWiki

Overview[ - collapse ][ - ]

Purpose	This study is being done to understand metformin's mechanisms of action regarding glucose production, protein metabolism, and mitochondrial function.
Condition	Insulin Resistance Prediabetic State
Intervention	Drug: Metformin Drug: Placebo
Phase	N/A
Sponsor	Mayo Clinic
Responsible Party	Mayo Clinic
ClinicalTrials.gov Identifier	NCT01956929
First Received	September 23, 2013
Last Updated	April 9, 2014
Last verified	April 2014

Tracking Information[ + expand ][ + ]

First Received Date	September 23, 2013
Last Updated Date	April 9, 2014
Start Date	October 2013
Estimated Primary Completion Date	August 2014
Current Primary Outcome Measures	Change in Glucagon-induced endogenous glucose production. [Time Frame: Measured at week 0, 2, 4, 6 and 8] [Designated as safety issue: No]To assess the effect of Metformin on glucose metabolism, at baseline and during a period of hyperglucagonemia, endogenous glucose production will be measured using a stable isotope tracer during the application of a somatostatin-based pancreatic clamp. Participants will be assessed before and following two weeks of consuming either metformin or placebo.
Current Secondary Outcome Measures	Change in glucagon-induced alterations in whole body protein metabolism and resting energy expenditure. [Time Frame: Measured at week 0, 2, 4, 6 and 8] [Designated as safety issue: No]Alterations in whole body protein metabolism will be measured by using leucine as a tracer that measures leucine flux, and leucine transamination and oxidation as measures of leucine catabolism. Whole body oxygen consumption will be assessed by open circuit indirect calorimetry with a ventilated hood system. Skeletal muscle biopsies will be obtained at baseline and four hours after a high fat, high glycemic meal. Mitochondria will be isolated from the muscle samples to assess mitochondrial oxygen consumption and hydrogen peroxide emissions using high-resolution respirometry and spectrofluorometry, respectively. In addition, we will measure skeletal muscle intracellular AMP-activated protein kinase activity.

Descriptive Information[ + expand ][ + ]

Brief Title
Official Title	Metformin's Effect on Glucagon-induced Endogenous Glucose Production, Protein Metabolism and Resting Energy Expenditure in Insulin Resistant Individuals.
Brief Summary	This study is being done to understand metformin's mechanisms of action regarding glucose production, protein metabolism, and mitochondrial function.
Detailed Description	It is believed that Metformin antagonizes the action of glucagon through different pathways. In mice, Metformin leads to inhibition of adenylate cyclase, reduction of levels of cyclic AMP and protein kinase A (PKA) activity, therefore blocking glucagon-dependent glucose output form hepatocytes. Glucagon plays an important role in the increased catabolic state seen in insulin deficiency. Hyperglucagonaemia states have been shown to accelerate proteolysis and leucine oxidation in insulin-deficient humans. Patients with insulin resistance and increased levels of glucagon have an increased in energy expenditure which may contribute to the catabolic state associated with this condition. We hypothesized that treatment with Metformin for 2 weeks will significantly inhibit glucagon-induced endogenous glucose production in insulin resistant individuals. We also hypothesized that glucagon-induced alterations in whole body protein metabolism and the increases in O2 consumption associated with hyperglucagonaemia states will be significantly inhibited by Metformin in these individuals. This would open the door for the development of other antidiabetic drugs with antagonism of glucagon as their principal mechanism of action.
Study Type	Interventional
Study Phase	N/A
Study Design	Allocation: Randomized, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Basic Science
Condition	Insulin Resistance Prediabetic State
Intervention	Drug: Metformin Metformin 1000mg daily for one week, then 2000 mg daily for the second week. 4 week washout period, then crossover to placebo. Other Names: GlucophageDrug: Placebo Placebo tablets for 2 weeks, then 4 weeks of washout period, then crossover to metformin. Other Names: Lactulose
Study Arm (s)	Experimental: Metformin 2 weeks of Metformin use. First week 1000mg/day, Second week Max dose of 2000 mg/day. Placebo Comparator: Placebo 2 weeks of Placebo (lactulose pills)

Recruitment Information[ + expand ][ + ]

Recruitment Status	Recruiting
Estimated Enrollment	30
Estimated Completion Date	August 2014
Estimated Primary Completion Date	August 2014
Eligibility Criteria	Inclusion Criteria: - 35-65 years of age - Fasting blood glucose >100 mg/dl - BMI 27-36 kg/m2 - Waist Circumference: Men ≥ 104 cm; women ≥ 88 cm - If previously on anti-diabetic medication, should be off for at least 1 month Exclusion Criteria: - Active use of hypoglycemic agents (< 1 month) - Renal failure, creatinine ≥ 1.5 mg/dL in men or ≥ 1.4 mg/dL in women - Alanine aminotransferase levels exceed 135 IU/L or aspartate aminotransferase levels exceed 129 IU/L (3 x the upper limit of normal) - Congestive Heart Failure (EF < 40 %) - Active coronary artery disease - Recent (less than 6 weeks) or planned imaging study requiring IV contrast - Participation in structured exercise (> 2 hr per week) - Recent change in dietary habits or weight - Tobacco use - Use of systemic glucocorticoids - Anti-coagulant therapy (warfarin/heparin) - Pregnancy or breastfeeding - Alcohol consumption greater than 2 drinks/day - Uncontrolled Hypothyroidism, abnormal thyroid stimulating hormone levels - Metformin Allergy
Gender	Both
Ages	35 Years
Accepts Healthy Volunteers	Accepts Healthy Volunteers
Contacts	Contact: Lynne Johnson 507 255 8932 johnson.lynne@mayo.edu
Location Countries	United States

Administrative Information[ + expand ][ + ]

NCT Number	NCT01956929
Other Study ID Numbers	13-004966
Has Data Monitoring Committee	No
Information Provided By	Mayo Clinic
Study Sponsor	Mayo Clinic
Collaborators	Not Provided
Investigators	Principal Investigator: K Nair, MD, PhD Mayo Clinic
Verification Date	April 2014

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