NCT01517100

The Role of Endocannabinoids in Insulin Production and Action

The Roles of Endocannabinoids in Insulin Secretion and Action

• Status: Completed
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 45 (actual)
• Sponsor: National Institute on Aging (NIA) · NIH
• Sex: All
• Age: 21 Years – 55 Years
• Healthy volunteers: Not accepted

Summary

Background: \- The endocannabinoid system is involved in different body functions and processes. It helps regulate appetite and mood, and sends signals to the nervous system. It may also be involved in how the body produces insulin during digestion. Researchers want to test two drugs that work on the endocannabinoid system: nabilone and CP-945,598. These drugs may be able to affect insulin levels in the blood. This information may suggest possible new treatments for people with diabetes. Objectives: \- To study how the endocannabinoid system is involved in insulin production and action. Eligibility: \- Healthy men between 21 and 55 years of age. Design: * Participants will be screened with a physical exam and medical history. They will provide blood and urine samples. They will also have imaging studies to test their brain responses, especially to food-related cues. Some participants will also have a study visit to test their insulin resistance levels. * Participants will have four separate study visits 6 weeks apart. They will keep a food diary before each visit. At each visit, they will have one of the following combinations of drugs: * Double placebo * Placebo and nabilone * Placebo and low dose of CP-945,598 * Placebo and high dose of CP-945,598. * Participants will have follow-up visits 1 week after each study visit. Blood samples will be taken.

Detailed description

Objectives and Specific Aims: We plan to investigate whether the endocannabinoid system is involved in the regulation of insulin secretion from Beta cells and in the modulation of insulin action in peripheral tissues in humans. We hypothesize that cannabinoid receptor 1 (CB1R) antagonist CP-945,598 will increase insulin secretion from Beta cells and improve insulin sensitivity in peripheral tissues while cannabinoid receptor (CBR) agonist nabilone will decrease insulin secretion from Beta cells and worsen insulin sensitivity in peripheral tissues. Moreover, we will investigate the brain s control over the initial phase of insulin secretion (cephalic insulin response) and the effect of central cannabinoid receptors. Experimental Design and Methods: Twenty healthy men, age 21-55, will be recruited for this study. This is a randomized, double-blind, placebo-controlled cross-over study. Each subject will serve as his own control and each person will have four different intervention visits spaced at least 6 weeks apart. During each visit, they will receive one of the following medications in random order: placebo, nabilone 2 mg, CP-945,598 15 mg, or CP-945,598 45 mg. A sequential hyperglycemic-euglycemic clamp procedure and a 3-hr oral glucose tolerance test will be used to study the effect of CP-945,598 and nabilone on insulin secretion and insulin action in healthy men. To identify brain areas involved in cephalic insulin response, a functional MRI will be used to assess brain activation in response to food images in association with frequent blood sampling. Medical Relevance and Expected Outcome: Based on our pre-clinical animal data, CB1R antagonist enhances insulin secretion and action in response to glucose while CBR agonist virtually shuts off insulin secretion and worsens insulin action in response to glucose. The application of novel, pre-clinical findings to an understanding of human biology and pathobiology is of fundamental and critical importance. This study will give us a better understanding of the regulators of insulin secretion from Beta cells and insulin sensitivity in humans, and this new understanding is of importance to finding new treatments for type 2 diabetes.

Conditions

• Healthy Volunteers

Interventions

Type	Name	Description
OTHER	Nabilone	CB agonist
DRUG	CP-945,598	Cannabinoid Receptor 1 antagonist
OTHER	hyperglycemic clamp	assesses beta cell response
OTHER	euglycemic-hyperinsulinemic clamp	measures insulin sensitivity
OTHER	Nabilone	cannabinoid receptor agonist

Timeline

• Start date: 2012-01-05
• Primary completion: 2014-10-06
• Completion: 2014-10-06
• First posted: 2012-01-25
• Last updated: 2026-03-31

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study