Gastrointestinal Sensorimotor Dysfunctions in Diabetes Mellitus

Phase 2

Completed

Conditions: Dyspepsia
Diabetes Mellitus With Gastrointestinal Symptoms

Interventions: Drug: Exendin 9-39
Drug: Placebo
Drug: Microlipid

Registration Number: NCT02170870

Lead Sponsor: Mayo Clinic

Brief Summary: The purpose of this study is to understand why people with indigestion have gastrointestinal symptoms and in particular to understand whether symptoms are related to increased sensitivity to nutrients in the small intestine and to a hormone (GLP1) which is normally released from the small intestine in response to nutrients. We propose to study the contribution of GLP1 to intestinal sensitivity with a drug (exendin 9-39) that blocks the effects of GLP1.

Detailed Description: Upper gastrointestinal symptoms (early satiety, pain, nausea, and vomiting) are not uncommon in diabetic (DM) enteropathy. While these symptoms are often attributed to accelerated or delayed gastric emptying, the precise contribution of abnormal gastric emptying to symptoms in patients with DM gastroparesis is often unclear.

The investigators recently observed that approximately 50% of patients with functional dyspepsia have increased sensation to duodenal nutrient (carbohydrate and lipid) perfusion. Another recent study suggests that patients with functional dyspepsia have low-grade mucosal inflammation, abnormalities of cell-to-cell adhesion proteins which predispose to increased epithelial permeability, and a leaky epithelial barrier. Type 1 DM is associated with increased small intestinal permeability even in subjects who do not have celiac disease.

Hence, the investigators proposed to evaluate the overall hypothesis that intestinal chemosensitivity related to increased epithelial permeability and GLP-1 explains symptom severity in patients with functional dyspepsia and in patients with DM and dyspepsia. Healthy subjects, Patients with DM and GI symptoms, and patients with functional dyspepsia underwent assessment of intestinal chemosensitivity during duodenal nutrient perfusion, gastric emptying (by scintigraphy), cardiovascular and GI vagal functions (plasma pancreatic polypeptide response to sham feeding and a comprehensive autonomic reflex screen), in vivo assessment of small intestinal permeability (urinary lactulose:mannitol ratio), and upper endoscopy with assessment of epithelial tight junction proteins and permeability on small bowel biopsies.

During the nutrient infusion, subjects in each group (i.e., healthy subjects, functional dyspepsia and DM) were randomized to lipid infusion and placebo or lipid infusion and exendin 9-39. Hormonal responses (i.e., GLP-1, cholecystokinin (CCK), gastric inhibitory polypeptide (GIP), glucagon, peptide tyrosine tyrosine (PYY), C-peptide, and insulin) and plasma glucose will also be evaluated during enteral nutrient infusion. GI symptoms during each perturbation (meal, nutrient infusion) will be evaluated by validated questionnaires. Blood will be collected for DNA-based genetic analyses, initially to assess the relationship of GI sensorimotor dysfunctions and symptoms with single nucleotide polymorphisms (SNPs) affecting CCK and GLP-1 receptors. The analysis will assess for disturbances in these parameters in functional and DM dyspepsia, investigate associations between symptoms during enteral infusion and hormonal-epithelial functions, and evaluate relationships between daily symptoms and results of testing.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 104

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Diabetics Placebo	Placebo	Normal saline infusion was prepared to match the appearance of Exendin 9-39. Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Healthy Controls Exendin 9-39	Exendin 9-39	Exendin 9-39 was administered intravenously (1,200 pmol/kg bolus followed by infusion at 300 pmol/kg/min). Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Healthy Controls Exendin 9-39	Microlipid	Exendin 9-39 was administered intravenously (1,200 pmol/kg bolus followed by infusion at 300 pmol/kg/min). Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Healthy Controls Placebo	Microlipid	Normal saline infusion was prepared to match the appearance of Exendin 9-39. Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Healthy Controls Placebo	Placebo	Normal saline infusion was prepared to match the appearance of Exendin 9-39. Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Diabetics Exendin 9-39	Microlipid	Exendin 9-39 was administered intravenously (1,200 pmol/kg bolus followed by infusion at 300 pmol/kg/min). Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Diabetics Placebo	Microlipid	Normal saline infusion was prepared to match the appearance of Exendin 9-39. Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Functional Dyspepsia Exendin 9-39	Microlipid	Exendin 9-39 was administered intravenously (1,200 pmol/kg bolus followed by infusion at 300 pmol/kg/min). Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Functional Dyspepsia Placebo	Microlipid	Normal saline infusion was prepared to match the appearance of Exendin 9-39. Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Functional Dyspepsia Placebo	Placebo	Normal saline infusion was prepared to match the appearance of Exendin 9-39. Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Functional Dyspepsia Exendin 9-39	Exendin 9-39	Exendin 9-39 was administered intravenously (1,200 pmol/kg bolus followed by infusion at 300 pmol/kg/min). Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).
Diabetics Exendin 9-39	Exendin 9-39	Exendin 9-39 was administered intravenously (1,200 pmol/kg bolus followed by infusion at 300 pmol/kg/min). Lipid infusion 66.7 mL Microlipid (0.5 gm/mL diluted in water to 222 ml).

Primary Outcome Measures

Name	Time	Method
Mean Intestinal Chemosensitivity to Lipids Perfusion	Day 1, approximately 2 hours after infusion	Intestinal chemosensitivity was recorded by evaluating symptoms during duodenal lipid infusion (0.5 gm/mL diluted in water to 222 mL) and placebo or the glucagon like peptide 1 (GLP-1) receptor antagonist exendin 9-39 over 2 hours. Participants reported the severity of 6 symptoms (nausea, fullness, bloating, abdominal pain, belching, and burning) at 15 minute intervals using a Visual Analogue Scale (VAS) marked 0 (minimum value) - 4 (maximum value): absent (0), light (1), moderate (2), severe (3) and intolerable(4). The scores recorded for nausea, fullness, bloating, and abdominal pain over the 2 hour infusion were averaged and reported as the mean symptom score. Higher scores mean a worse outcome.

Secondary Outcome Measures

Name	Time	Method
Rate of Gastric Emptying (GE t 1/2) in Patients With Diabetes Mellitus (DM) or Non-ulcer Dyspepsia (NUD) Compared to Placebo	Day 1	The time for half of the ingested solids or liquids to leave the stomach. Following a meal consisting of two eggs labeled with technetium Tc 99m sulfur colloid (1 mCi) served on one slice of bread with milk labeled with indium In111 diethylenetriaminepentaacetate (0.1 mCi), gastric emptying of solids and liquids was assessed with scintigraphy. Rapid emptying is defined as ≥ 36% emptied at one hour and delayed emptying is defined as \< 76% emptied at four hours. Normal emptying is defined as amount less than rapid emptying definition but greater than delayed emptying definition.