The Effects of Glucagon on Hepatic Metabolism


About this study

The purpose of this study is to measure hepatic extraction of amino acid (AA) in response to physiologic post-prandial concentrations of glucagon. In addition to changes in essential AA, we will also measure the extraction of other AAs, and their metabolites, across the liver. While measuring the effect of glucagon on AA metabolism, we will also examine how EGP and hepatic lipid metabolism respond to these conditions. While early reports have focused on hepatic steatosis, we will ascertain if its presence is necessary to alter glucagon’s actions on hepatic


Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria;

  • Age > 25 or < 65 years.
  • HbA1c ≥ 8.5%.
  • BMI ≤ 28 Kg/M^2 (for lean participants).
  • BMI ≥ 25 Kg/M^2 (for obese participants).
  • Use of diet, sulfonylureas or metformin only (for T2DM participants).
  • For female subjects: negative pregnancy test at the time of enrollment and study.
  • No history of prior upper abdominal surgery such as adjustable gastric banding, pyloroplasty and vagotomy.
  • No active systemic illness or malignancy.
  • No symptomatic macrovascular or microvascular disease.
  • No contraindications to MRI (e.g., metal implants, claustrophobia).
  • Hematocrit > 35%.
  • TSH > 0.4 or < 5.5.
  • Consumption of < 2 alcohol drinks per day or < 14 per week or a negative AUDIT questionnaire.
  • No allergy to iodine.

Exclusion Criteria:

  • Age < 25 or > 65 years (to avoid studying subjects who could have latent type 1 diabetes, or the effects of age extremes in subjects with normal or impaired fasting glucose).
  • HbA1c ≥ 8.5%.
  • BMI ≤ 28 Kg/M^2.
  • Use of insulin or agents other than sulfonylureas or metformin.
  • For female subjects: positive pregnancy test at the time of enrollment or study.
  • History of prior upper abdominal surgery such as adjustable gastric banding, pyloroplasty and vagotomy.
  • Active systemic illness or malignancy.
  • Symptomatic macrovascular or microvascular disease.
  • Contraindications to MRI (e.g., metal implants, claustrophobia).
  • Hematocrit < 35%.
  • TSH < 0.4 or > 5.5.
  • Consumption of > 2 alcohol drinks per day or > 14 per week or a positive AUDIT questionnaire.
  • Allergy to iodine.

Eligibility last updated 1/6/22. Questions regarding updates should be directed to the study team contact.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Adrian Vella, M.D.

Closed-enrolling by invitation

What is this? (?)
Not open to everyone who meets the eligibility criteria, but only those invited to participate by the study team.

Contact information:

Adrian Vella M.D.

(507) 284-1920

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