Low Density Lipoprotein (LDL) Cholesterol Metabolism in Impaired Glucose Tolerance
Condition: Impaired Glucose Tolerance
MeSH terms: Glucose Intolerance
Study type: Observational

Summary: 
      Impaired glucose tolerance is associated with an increased risk of developing cardiovascular
      disease and atherosclerosis for reasons not yet totally understood. Previous studies
      evaluated the kinetics of plasma LDL and a faster removal rate of free cholesterol in
      normolipidemic patients with diagnosed arterial coronary disease and deposits of this
      cholesterol on the blood vessel walls. This disassociation of the cholesterol may suggest a
      new mechanism for not only the genesis but for the progression of arterial coronary disease.
      The objective of this research was to study the plasma kinetics of free cholesterol and
      cholesterol ester in impaired glucose tolerance patient, asymptomatic for coronary artery
      disease (CAD), to elucidate mechanisms involved in atherogenesis in these patients.
    

Detailed description: 
      Along with hyperglycemia, the presence of obesity and dyslipidemia, risk factors associated
      with the natural onset of diabetes mellitus type 2, could possibly explain the high
      susceptibility of the glucose intolerance to cardiovascular disease. Dyslipidemia commonly
      linked to glucose intolerance is characterized by hypertriglyceridemia, low HDL-C and in
      spite of the LDL-C being apparently normal or slightly elevated, there is presence of small
      dense LDL. Formulated in the laboratory, an artificial lipid nanoemulsion marked with both
      14C-cholesterol ester and 3H-cholesterol with lipid composition similar to LDL allows study
      the plasma kinetics of the two forms of cholesterol (free and esterified. The nanoemulsion
      mimics the natural LDL, but is prepared without protein. In contact with the bloodstream, the
      nanoemulsion acquires apolipoproteins, apo E preferentially, allowing it to be recognized and
      removed from plasma by LDL receptor. The application of this nanoemulsion was shown to be
      technically safe, appropriate and simple to be used in humans in order to understand the role
      of dyslipidemia in the atherogenic process.
    

Intervention name(s): Plasma kinetic study
Intervention type(s): Other
Intervention description(s): This study is done with the injection of an artificial lipid nanoemulsion doubly labeled with 14C-cholesteryl oleate and 3H-cholesterol, with a total radioactivity injection dose of 0.03mSV. Blood samples collected in a pre established period of time in 24 hours.
Other intervention name(s): Artificial lipid nanoemulsion
Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Patients with impaired glucose tolerance and controls were recruited from the Hospital of
        Clinics, Some were patients and staff of the Heart Institute and patients treated in
        outpatient clinics, offices and clinics outside the Hospital of Clinics of University of
        São Paulo.
      
Biospecimen description: 
      whole blood samples