Effects of Liraglutide on ER Stress in Obese Patients With Type 2 Diabetes

Effects of Liraglutide on Endoplasmic (ER) Stress in Obese Patients With Type 2 Diabetes

The main objective of the study will be to test the hypothesis that treatment with Liraglutide will decrease ER stress and adipose tissue in obese patients with type 2 diabetes. Experimental Approach: The investigators will use a prospective, single blind, placebo controlled study design to study 12 obese patients with type 2 diabetes mellitus (T2DM). 6 patients will first receive Liraglutide for 24 weeks followed by placebo for 12 weeks. The other 6 patients will first receive placebo for 12 weeks followed by Liraglutide for 24 weeks.

Measurements: The investigators will determine glycemic control (with HbA1c), body composition (bioelectric impedance analysis), insulin sensitivity (with hyperinsulinemic-euglycemic clamps), insulin secretion (with oral glucose tolerance testing), energy balance (calories in vs. calories out), plasma lipid levels and obtain subcutaneous fat biopsies to determine ER stress response markers before and after placebo and before and after Liraglutide treatment.

Study Overview

• Status: Active, not recruiting
• Conditions: Type 2 Diabetes
• Intervention / Treatment: Drug: Liraglutide

Detailed Description

This will be a prospective, single-blind, placebo-controlled study with a crossover design.

Visit Procedures: After a 1 month run-in period during which there will be no changes in medications, physical activity or diet, patients will be randomly divided into 2 groups of 6 patients each. Subjects have a 50:50 chance of being randomized to either group 1 or group 2.

In Group 1, (n=6), liraglutide will be started first with 0.6 mg/d for 1 week, then increased to 1.2 mg/d from week 2 to week 12, followed by 1.8 mg/d from week 12 to week 24. Group 1 patients will then be switched from liraglutide to placebo injections for another 12 weeks. For subjects in Group 1 the placebo period (weeks 24 to 36 will be the washout period.

Group 2 patients (n=6) will be started with placebo for 12 weeks and then switched to liraglutide for the next 24 weeks (0.6 mg/d for 1 week, 1.2 mg/d for 11 weeks and 1.8 mg/d for 12 weeks).

Assessment of Efficacy

Outpatient visits:

During the entire study, all patients (Groups 1 and 2) will perform home glucose monitoring 7 times/day (pre and ~ 2 h post breakfast, lunch and dinner and bedtime) and will be seen at Temple University Hospital as outpatients at 4 week intervals.

One week before the first, second or third and final inpatient visit, patients will undergo a 75, gram 2-hour oral glucose tolerance test.

Inpatient visits:

All patients (Groups 1 and 2) will be studied in our Clinical Research Center (CRC) at Temple University Hospital in the morning after an overnight fast, at the end of the run-in period (Week 0 ) and again at Weeks 12, 24 and 36. All study patients will be admitted to the CRC the evening before their study and discharged in the afternoon of the following day.

During the inpatient visits, the following procedures will be performed.

1. At baseline and again at weeks 12 and 36, subcutaneous fat biopsies will be obtained from the lateral aspect of one thigh by a surgeon as described (8) for determination of ER stress markers. In brief, the skin will be cleaned with betadine and anesthetized with 1% lidocaine without epinephrine in a field block pattern (at 2 X 3 in). (We have found that injection of lidocaine too close to the biopsy site interfered with the measurement of acetyl-CoA). After an incision (~ 1 in.) will be made through the skin, ~ 300 mg of fat will be mobilized and excised. The fat will be dropped immediately into isopentane, kept at its freezing point (-160°C) by liquid nitrogen. The frozen fat will be stored at -70°. To screen for changes in unfolded protein response (UPR) genes, we will first perform an UPR PCR microarray (SA Biosciences, Frederick, MD) using pooled fat biopsy extracts. This array profiles expression of 84 key genes recognizing and responding to misfolded protein accumulation in the ER. Significant changes (> 1.5 fold comparing post vs. pre drug biopsies) will then be confirmed by real time reverse transcription (RT)-PCR of the UPR messenger RNAs (mRNAs). Thus, mRNAs of the identified UPR markers (for instance, GRP78, X-box-binding-protein 1 (XBP-1), activating transcription factor 4 (ATF4), activating transcription factor 6 (ATF6), protein disulfide isomerase (PDI), calreticulin, calnexin) will be measured by real time RT-PCR in triplicate and normalized against 18s and β-actin mRNAs and will be expressed as arbitrary units. The respective proteins will be analyzed by Western blots.

2. Glycemic control will be assessed by

   1. measurement of HbA1c
   2. patients home glucose monitoring records
3. Determination of insulin resistance will be determined (with euglycemic-hyperinsulinemic clamping with use of stable isotopes for determination of peripheral (GRd) and hepatic (GRa) insulin action as described (18).
4. . Determination of energy balance, which will be calculated as change in fat mass (by bioelectric impedance analysis) plus total energy expenditure (determined with indirect calorimetry and the doubly labeled water method) (17).
5. Postabsorptive blood samples will be obtained for determination of plasma lipids (total cholesterol, LDL, HDL and triglycerides).
6. Assessment of changes in insulin secretion will be determined with Oral Glucose Tolerance Testing.

• Study Type: Interventional
• Enrollment (Anticipated): 12
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19140
      • Temple University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patients with established type 2 diabetes, BMI 27-35, Age - 18-75 years, HbA1c 7-10%, patients treated with exercise, diet, metformin and/or alpha glucosidase inhibitors (all up to ½ of their maximal dose) or pioglitazone (up to 30 mg/d), ability to provide informed consent before any trial-related activities.

Exclusion Criteria:

• Patients with pancreatitis or a history of pancreatitis, patients with HbA1c < 7% or > 10%, type 2 diabetic patients treated with insulin, sulfonylureas, meglitinides, dipeptidyl peptidase-4 (DPP4) inhibitors, glucagon-like peptide-1 (GLP1) agonists or corticosteroids, patients with hypoglycemia unawareness and with impaired liver functions (≥ 2.5 times the upper normal limit), known or suspected allergy against liraglutide or contraindications to liraglutide (as specified in the product prescribing information), pregnancies, breastfeeding or intention of becoming pregnant or not using adequate contraceptive measures, patients with a personal or family history of medullary thyroid cancer and patients with Multiple Endocrine Neoplasia type 2.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Liraglutide; Liraglutide will be started first with 0.6 mg/d for 1 week, then increased to 1.2 mg/d from week 2 to week 12, followed by 1.8 mg/d from week 12 to week 24.	Drug: Liraglutide; Crossover design - 24 weeks on active drug and 12 weeks daily placebo; Other Names: Victoza
Placebo Comparator: Placebo; Subjects will receive placebo for 12 weeks.	Drug: Liraglutide; Crossover design - 24 weeks on active drug and 12 weeks daily placebo; Other Names: Victoza

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in unfolded protein response markers	Changes in unfolded protein response markers in adipose tissue biopsy samples. Specifically, the investigators will determine changes in mRNA (by RT-PCR) and protein (by Western blots) levels of the following ER stress markers: GRP78, ATF4, XBP-1s, PDI, calreticulin and calnexin.	baseline, 6 months, 9 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Insulin sensitivity	Changes in insulin resistance will be determined by measuring changes in total body glucose uptake and in plasma free fatty acid (FFA) levels during euglycemic-hyperinsulinemic clamping.	baseline, 3 months, 6 months and 9 months
Glucose control	Glucose control will be assessed by monthly A1c determinations.	baseline, 1 month, 2 months, 3 months, 4 months, 5 months, 6 months, 7 months, 8 months, 9 months
Energy expenditure	Changes in energy expenditure will be assessed by indirect calorimetry	baseline, 3 months, 6 months, 9 months
Body weight	Patients will be weighed monthly	baseline, 1 month, 2 months, 3 months, 4 months, 5 months, 6 months, 7 months, 8 months, 9 months
Body composition	Body composition will be determined using bioelectrical impedance.	baseline, 3 months, 6 months and 9 months
Beta cell function	Subjects will undergo an oral glucose tolerance tests(OGTT) to assess beta cell function.	baseline, 6 months, 9 months

Collaborators and Investigators

• Sponsor: Temple University
• Investigators: Principal Investigator: Ajaykumar D Rao, MD, Temple University

Study record dates

Study Major Dates

• Study Start: May 1, 2014
• Primary Completion (Anticipated): December 31, 2022
• Study Completion (Anticipated): December 31, 2023

Study Registration Dates

• First Submitted: January 14, 2015
• First Submitted That Met QC Criteria: January 16, 2015
• First Posted (Estimate): January 22, 2015

Study Record Updates

• Last Update Posted (Actual): July 29, 2022
• Last Update Submitted That Met QC Criteria: July 27, 2022
• Last Verified: July 1, 2022

More Information

Terms related to this study

• Keywords: diabetes, ER stress, glucagon-like peptide-1 analogs
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 2; Hypoglycemic Agents; Physiological Effects of Drugs; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Incretins; Liraglutide
• Other Study ID Numbers: 21440