The Effect of A-lipoic Acid (ALA) on Fatty Acid-induced Impairment of Glucose-stimulated Insulin Secretion

This study has been completed.
Sponsor:
Collaborator:
Canadian Diabetes Association
Information provided by (Responsible Party):
Gary Lewis, University Health Network, Toronto
ClinicalTrials.gov Identifier:
NCT01056497
First received: December 17, 2009
Last updated: September 28, 2012
Last verified: September 2012
  Purpose

Chronically elevated free fatty acids impair insulin sensitivity and insulin secretion (ie lipotoxicity) by a combination of oxidative stress, endoplasmic reticulum (ER) stress and inflammation. This study will test whether alpha-lipoic acid, which has potent antioxidant and anti-inflammatory properties, prevents or ameliorates lipotoxicity.


Condition Intervention Phase
Type 2 Diabetes
Prediabetes
Drug: alpha lipoic acid
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Single Blind (Subject)
Primary Purpose: Basic Science
Official Title: The Effect of A-lipoic Acid (ALA) on Fatty Acid-induced Impairment of Glucose-stimulated Insulin Secretion

Resource links provided by NLM:


Further study details as provided by University Health Network, Toronto:

Primary Outcome Measures:
  • insulin secretion and insulin sensitivity To determine whether ALA ameliorates or prevents impairment of insulin secretion and insulin sensi [ Time Frame: 6 months ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • To determine the role of oxidative stress and inflammation in the pathogenesis of lipotoxicity [ Time Frame: 6 months ] [ Designated as safety issue: No ]

Estimated Enrollment: 15
Study Start Date: February 2010
Study Completion Date: June 2011
Primary Completion Date: January 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: alpha lipoic acid Drug: alpha lipoic acid
A 2 week treatment period with either oral ALA tablets or placebo tablets, followed by 30 hour hospital stay to infuse lipid or saline and to test insulin sensitivity and insulin secretion. For two weeks prior to each admission to hospital and during each hospital admission subjects will ingest 3 tablets 2 times per day with breakfast and supper, 1800mg per day
Other Names:
  • lipoic acid
  • ALA

Detailed Description:

Alpha-Lipoic Acid (ALA) is a naturally occurring dithiol compound absorbed intact from dietary sources and synthesized enzymatically in the mitochondrion from octanoic acid. It serves a critical role in mitochondrial energy metabolism and is a potent biological antioxidant. It is widely available as an over-the-counter health supplement. It has generated considerable interest among the lay public and the research community for the use of ALA as a nutritive supplement and as a pharmacotherapy for diabetes and many other disorders. There is growing evidence that ALA has beneficial effects on the treatment of type 2 diabetes (T2DM) and some of its complications. It represents an attractive pharmacological target in the treatment of T2DM by modulating the signal transduction pathways in insulin resistance and antagonizing the oxidative and inflammatory stresses, which are major pathways in the pathogenesis of this disorder. Chronic elevation of plasma FFAs are believed to contribute to insulin resistance and defects in insulin secretion by promoting oxidative stress and inflammation. A potent antioxidant and free radical scavenger, ALA also targets cellular signal transduction pathways, which increases glucose uptake and utilization, thus providing specific targeted therapy in the treatment of insulin resistance. ALA has been shown to be safe when taken in high doses (2400mg/d) for prolonged time periods (6 months and longer), even in patients with renal and liver failure. In fact no upper limit for ALA consumption in humans has been established.

  • Each subject will undergo 4 studies, 4 to 6 weeks apart. Each study will consist of a 2 week treatment period with either oral ALA tablets or placebo tablets, followed by 30 hour hospital stay to infuse lipid or saline and to test insulin sensitivity and insulin secretion.
  • The study will be conducted as a single blind study, with the subject not knowing whether they are receiving a placebo or ALA. For safety reasons and since it will not influence the results of this study it will not be conducted as a double blind study.
  • On each of four occasions, 4 weeks apart, after taking the tablets for 2 weeks, the subject will fast overnight for 12-hours prior to their admission to the Toronto General Hospital metabolic research ward for 30 hours to undergo testing as follows. The four studies will be conducted in random order:
  Eligibility

Ages Eligible for Study:   20 Years to 65 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

Men and women aged 20-65 years:

  1. Written informed consent obtained
  2. Body mass index (BMI) > 27kg/m2
  3. Glucose tolerance test may be normal or demonstrate impaired glucose tolerance but not frank diabetes
  4. Hemoglobin above 130g/L

Exclusion Criteria:

  1. Subject has a history of hepatitis/hepatic disease that has been active within the previous two years
  2. Any significant active (over the past 12 months) disease of the gastrointestinal, pulmonary, neurological, renal (Cr > 1.5 mg/dL) genitourinary, hematological systems, or has severe uncontrolled treated or untreated hypertension (sitting diastolic BP > 100 or systolic > 180) or proliferative retinopathy
  3. Type 2 diabetes by history or OGTT
  4. Any history of a MI or clinically significant, active, cardiovascular history including a history of arrhythmia's or conduction delays on ECG, unstable angina, or decompensated heart failure
  5. Any laboratory values: AST > 2x ULN; ALT > 2x ULN; TSH > 6 mU/l
  6. A history of multiple and/or severe allergies to drugs or foods or a history of severe anaphylactic reactions. History of hypersensitivity to heparin
  7. Current addiction to alcohol or substances of abuse as determined by the investigator
  8. Mental incapacity, unwillingness or language barrier precluding adequate understanding or cooperation
  9. Any lipid lowering of hypoglycemic agents
  10. Previous history of asthma
  11. Will not donate blood three months prior to and three months post study procedures
  12. Thrombocytopenia
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01056497

Locations
Canada, Ontario
Toronto General Hospital
Toronto, Ontario, Canada, M5G 2C4
Sponsors and Collaborators
University Health Network, Toronto
Canadian Diabetes Association
Investigators
Principal Investigator: gary F Lewis, MD University Health Network, Toronto General Hospital
  More Information

No publications provided

Responsible Party: Gary Lewis, Professor, Department of Medicine and Physiology, University Health Network, Toronto
ClinicalTrials.gov Identifier: NCT01056497     History of Changes
Other Study ID Numbers: 090818B, Canadian Diabetes Association
Study First Received: December 17, 2009
Last Updated: September 28, 2012
Health Authority: Canada: Ethics Review Committee

Keywords provided by University Health Network, Toronto:
diabetes
alpha lipoic acid
endoplasmic reticulum (ER) stress
insulin secretion
insulin sensitivity

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 2
Glucose Intolerance
Prediabetic State
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Hyperglycemia
Insulin
Thioctic Acid
Hypoglycemic Agents
Physiological Effects of Drugs
Pharmacologic Actions
Antioxidants
Molecular Mechanisms of Pharmacological Action
Protective Agents
Vitamin B Complex
Vitamins
Micronutrients
Growth Substances

ClinicalTrials.gov processed this record on July 10, 2014