A 28-year-old man presents with recurrent episodes of severe abdominal pain and pancreatitis. His triglyceride level is 1,800 mg/dL. He has earlobe creases and a family history of premature coronary disease. Genetic testing reveals a mutation in the apolipoprotein C-II gene. Which of the following best explains why his triglycerides are markedly elevated?

  1. A)Apolipoprotein C-II inhibits hepatic cholesteryl ester transfer protein
  2. B)Apolipoprotein C-II competitively inhibits apolipoprotein E binding
  3. C)Apolipoprotein C-II promotes VLDL secretion from hepatocytes
  4. D)Apolipoprotein C-II is a required cofactor for lipoprotein lipase activityGABARITO
  5. E)Apolipoprotein C-II prevents apolipoprotein B-100 oxidation

Explicação

Apolipoprotein C-II deficiency causes Type I hyperlipoproteinemia. ApoC-II is an essential cofactor for lipoprotein lipase, the enzyme responsible for hydrolyzing triglycerides in chylomicrons and VLDL. Without it, triglyceride clearance is severely impaired. Ver explicação completa e trilha adaptativa →

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