High Density Lipoprotein (HDL) Functionality in Metabolic Syndrome

The recruitment status of this study is unknown because the information has not been verified recently.
Verified February 2009 by The University of Western Australia.
Recruitment status was  Recruiting
Sponsor:
Information provided by:
The University of Western Australia
ClinicalTrials.gov Identifier:
NCT00716300
First received: July 14, 2008
Last updated: February 17, 2009
Last verified: February 2009
  Purpose

The aim of the study is to examine the kinetic, anti-oxidant, anti-inflammatory and cellular cholesterol efflux properties of high-density lipoprotein (HDL) in subjects with the metabolic syndrome (MetS) and lean individuals.


Condition
Metabolic Syndrome X

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Cross-Sectional
Official Title: Functional Studies of High Density Lipoprotein in the Metabolic Syndrome

Resource links provided by NLM:


Further study details as provided by The University of Western Australia:

Biospecimen Retention:   Samples With DNA

DNA plasma


Estimated Enrollment: 30
Study Start Date: July 2008
Estimated Study Completion Date: December 2009
Estimated Primary Completion Date: June 2009 (Final data collection date for primary outcome measure)
Groups/Cohorts
1
obese and insulin resistant subjects
2
lean and normolipidaemic subjects

Detailed Description:

Background and Purpose of This Study:

The metabolic syndrome (MetS) is characterized by impaired glucose and insulin metabolism (insulin resistance), abnormal body fat distribution called central obesity (a pot belly) and high blood pressure. People with the metabolic syndrome have markedly increased risk of heart disease which is mainly attributed to the abnormal fat metabolism and its associated metabolic disorders. Therefore, understanding of the body fat disorder is important to reduce the incidence and severity of heart disease.

Fats in the blood originate from dietary sources and from production by the liver. They are then delivered into peripheral body cell for utilization or storage. A particular protein, called high-density lipoprotein (HDL) apolipoprotein (apo) A-I, is an important fat carrier responsible for transporting excess fat from cells, via the bloodstream, back to the liver. Low HDL-apoA-I concentration is related to increased risk of heart disease. Subjects with MetS have reduced level of apoA-I and we wish to test the hypothesis that it is responsible for the impaired movement of fat from the periphery to the liver. Recent evidence suggests that the functionality of HDL, including anti-oxidant, anti-inflammatory and cholesterol efflux properties, is also important in preventing the development of heart disease. However, these function tests have not yet been investigated extensively in MetS.

Consequently, we wish to examine the transport and anti-atherogenic properties of HDL in subjects with MetS and compare these with normal lean subjects. Such findings would be of significant clinical importance in the understanding of the diverse role of HDL-apoA-I in reducing or preventing the progression of heart disease.

Participation:

Patients with MetS or lean individuals will be recruited for the study via newspaper advertisements. Following informed consent and once found suitable for participation, 15 men with MetS and 15 lean men will be enrolled. We will give the participants a harmless substance called a stable (non-radioactive) isotope. The isotope will trace the speed at which apoA-I is released into the blood (production) and are removed from the bloodstream (clearance) by the liver.

Participants will be asked to fast (only water allowed) for 12 hours prior to the isotope study. The stable isotope will be administered by intravenous injection in the form of a clear fluid (total volume approximates 15 to 25ml, 1-1.5 tablespoons). A small plastic tube (a cannula) will be placed into a vein in the arm, from where a total of 160mll (10.5 tablespoons) of blood will be obtained. The isotope study lasts 10 hours, during which participants will rest quietly and be allowed water only. At the end of the study day, participants will be given a meal and will be allowed home by taxi or family transport.

These studies will allow us to measure the metabolic action of apolipoprotein A-I, thereby gaining a better understanding of the mechanisms that leads to abnormal blood fat levels in those with MetS. To complete this study, each participant is required to attend 7 visits over a 6-week period.

Benefits:

All participants will receive health education, as well as information on personal health status and a review of heart risk factors.

  Eligibility

Ages Eligible for Study:   20 Years to 75 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population

15 men with features of the metabolic syndrome 15 age-matched normolipidaemic men

Criteria

Inclusion Criteria:

MetS :the presence of at least three of the following:

  • waist circumference > 102 cm, triglycerides > 1.7 mmol/L, HDL cholesterol < 1.05 mmol/L
  • blood pressure ≥ 130/ ≥ 85 mmHg
  • fasting glucose > 6.1 mmol/L

Lean control:

  • BMI < 25 kg/m2
  • waist circumference < 102 cm
  • triglycerides < 1.0 mmol/L
  • HDL-cholesterol > 1.3 mmol/L

Exclusion Criteria:

  • subjects with plasma LDL-cholesterol > 5 mmo/L
  • diabetes mellitus (defined by oral glucose tolerance test)
  • genetic hyperlipidaemia (e.g. FH)
  • consumption of > 30 g alcohol/day
  • apolipoprotein E2/E2 genotype
  • macroproteinuria
  • creatinaemia ( > 120 umol/L)
  • hypothyroidism
  • hepatic dysfunction (AST or ALT > 2x ULN)
  • major systemic illness and use of steroids or other agents that may influence lipid metabolism
  • cardiovascular event within the past 6 months
  • subjects on hypocaloric diets
  • anaemia; any significant illness that in the opinion of reviewing physician would bear on the study (e.g. heart murmur or psychiatric conditions)
  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: NCT00716300

Contacts
Contact: Dick C Chan, PhD 61-8-92240268 dick.chan@uwa.edu.au

Locations
Australia, Western Australia
University of Western Australia Recruiting
Perth, Western Australia, Australia, 6000
Contact: Dick C Chan, PhD    61-8-92240268    dick.chan@uwa.edu.au   
Sponsors and Collaborators
The University of Western Australia
Investigators
Principal Investigator: Gerald F Watts, MBBS The University of Western Australia
  More Information

No publications provided

Responsible Party: Prof Gerald F Watts, University of Western Australia
ClinicalTrials.gov Identifier: NCT00716300     History of Changes
Other Study ID Numbers: DC-HDL2008
Study First Received: July 14, 2008
Last Updated: February 17, 2009
Health Authority: Australia: National Health and Medical Research Council

Keywords provided by The University of Western Australia:
obesity
CVD
HDL kinetics
Anti-inflammatory and anti-oxidation studies
30 subjects recruited (15 MetS and 15 lean controls)

Additional relevant MeSH terms:
Metabolic Syndrome X
Insulin Resistance
Hyperinsulinism
Glucose Metabolism Disorders
Metabolic Diseases

ClinicalTrials.gov processed this record on September 11, 2014