Podcast
Questions and Answers
Approximately what percentage of total cholesterol synthesis occurs in the liver?
Approximately what percentage of total cholesterol synthesis occurs in the liver?
High levels of HDL cholesterol increase the risk of atherosclerosis and coronary artery disease.
High levels of HDL cholesterol increase the risk of atherosclerosis and coronary artery disease.
False (B)
List two main mechanisms by which HDL exerts its anti-atherogenic action.
List two main mechanisms by which HDL exerts its anti-atherogenic action.
Reverse transport of cholesterol, transfer of cholesterol into lipoprotein particles
Familial hypercholesterolemia is characterized by impaired uptake of ______ particles, leading to elevated plasma levels of cholesterol.
Familial hypercholesterolemia is characterized by impaired uptake of ______ particles, leading to elevated plasma levels of cholesterol.
Signup and view all the answers
Match the following risk factors for coronary artery disease with their modifiability:
Match the following risk factors for coronary artery disease with their modifiability:
Signup and view all the answers
According to the information, which of the following is considered the only causal risk factor for atherosclerosis?
According to the information, which of the following is considered the only causal risk factor for atherosclerosis?
Signup and view all the answers
Dyslipidemia always involves an increase in anti-atherogenic HDL levels.
Dyslipidemia always involves an increase in anti-atherogenic HDL levels.
Signup and view all the answers
Name one genetic disease caused by disturbed cholesterol homeostasis mentioned in the text.
Name one genetic disease caused by disturbed cholesterol homeostasis mentioned in the text.
Signup and view all the answers
Which of the following is a clinical manifestation of dyslipoproteinemia and atherosclerosis?
Which of the following is a clinical manifestation of dyslipoproteinemia and atherosclerosis?
Signup and view all the answers
All patients with hypercholesterolemia should be treated with medication.
All patients with hypercholesterolemia should be treated with medication.
Signup and view all the answers
What is the target LDL level for very high-risk patients, according to the provided therapeutic guidelines (in mM/l)?
What is the target LDL level for very high-risk patients, according to the provided therapeutic guidelines (in mM/l)?
Signup and view all the answers
Statins inhibit the enzyme __________, which reduces the formation of mevalonate and subsequently lowers cholesterol production.
Statins inhibit the enzyme __________, which reduces the formation of mevalonate and subsequently lowers cholesterol production.
Signup and view all the answers
Match the following medications with their primary mechanism of action:
Match the following medications with their primary mechanism of action:
Signup and view all the answers
Which of the following is a common side effect of statin medications?
Which of the following is a common side effect of statin medications?
Signup and view all the answers
Fibrates increase the risk of cholesterol gallstones.
Fibrates increase the risk of cholesterol gallstones.
Signup and view all the answers
What is the primary effect of bile acid sequestrants on LDL levels?
What is the primary effect of bile acid sequestrants on LDL levels?
Signup and view all the answers
Which medication is considered the drug of choice for treating low HDL levels?
Which medication is considered the drug of choice for treating low HDL levels?
Signup and view all the answers
_______ are monoclonal antibodies that inhibit PCSK9, leading to lower LDL cholesterol levels.
_______ are monoclonal antibodies that inhibit PCSK9, leading to lower LDL cholesterol levels.
Signup and view all the answers
Flashcards
Cholesterol Synthesis
Cholesterol Synthesis
Cholesterol is synthesized by all cells, primarily in the liver, and is crucial for cell membranes.
Cholesterol's Role in Membranes
Cholesterol's Role in Membranes
Cholesterol helps regulate the rigidity, fluidity, and permeability of cell membranes.
HDL Cholesterol
HDL Cholesterol
High-Density Lipoprotein (HDL) is protective against atherosclerosis and coronary artery disease (CAD).
Reverse Cholesterol Transport
Reverse Cholesterol Transport
Signup and view all the flashcards
Familial Hypercholesterolemia
Familial Hypercholesterolemia
Signup and view all the flashcards
Risk Factors for CAD
Risk Factors for CAD
Signup and view all the flashcards
Dyslipidemia
Dyslipidemia
Signup and view all the flashcards
Causal vs. Non-Causal Factors in Atherosclerosis
Causal vs. Non-Causal Factors in Atherosclerosis
Signup and view all the flashcards
Combined hypertriacylglycerolemia
Combined hypertriacylglycerolemia
Signup and view all the flashcards
Clinical manifestations of dyslipoproteinemia
Clinical manifestations of dyslipoproteinemia
Signup and view all the flashcards
High risk patients for cardiovascular diseases
High risk patients for cardiovascular diseases
Signup and view all the flashcards
Goal LDL level for high risk patients
Goal LDL level for high risk patients
Signup and view all the flashcards
Statins
Statins
Signup and view all the flashcards
Ezetimibe
Ezetimibe
Signup and view all the flashcards
Fibrates
Fibrates
Signup and view all the flashcards
Bile acid sequestrants
Bile acid sequestrants
Signup and view all the flashcards
Niacin
Niacin
Signup and view all the flashcards
PCSK9 inhibitors
PCSK9 inhibitors
Signup and view all the flashcards
Study Notes
Cholesterol Synthesis and Function
- Cholesterol is synthesized by all cells, primarily located in cell membranes.
- Approximately half of total cholesterol synthesis occurs in the liver.
- Cholesterol synthesis is an energy-intensive process, strictly regulated.
- In membranes, cholesterol interacts with neighboring lipids, regulating membrane rigidity, fluidity, and permeability.
- Cholesterol is a precursor to steroid hormones, starting with pregnenolone.
HDL Cholesterol and Atherosclerosis
- High-density lipoprotein (HDL) cholesterol has a protective effect against atherosclerosis and coronary artery disease.
- Lower HDL levels correlate with increased risk of atherosclerosis and coronary artery disease.
- High triglycerides often accompany low HDL levels.
- HDL's anti-atherogenic action involves two main mechanisms:
- Reverse cholesterol transport (returning cholesterol from peripheral tissues to the liver).
- Transferring cholesterol to other lipoproteins (VLDL, IDL, or LDL).
Genetic Cholesterol Disorders
- Familial hypercholesterolemia is a prevalent genetic disorder increasing the risk of atherosclerosis.
- This condition involves impaired LDL uptake, leading to elevated LDL cholesterol levels in the blood.
- This disorder plays a significant role in atherogenesis.
- Niemann-Pick type C disease features cholesterol accumulation within lysosomes.
Coronary Artery Disease Risk Factors
- Non-modifiable risk factors include age, sex, and family history of coronary artery disease (CAD).
- Modifiable risk factors include dyslipidemia (high LDL, high triglycerides, low HDL), smoking, hypertension, diabetes, obesity, and dietary factors.
- Elevated LDL cholesterol is the causal risk factor for atherosclerosis; other factors primarily accelerate the process.
Dyslipidemia
- Dyslipidemia is a group of metabolic disorders characterized by elevated pro-atherogenic and pro-coagulant lipoproteins (LDL, lipoprotein(a), triglycerides) or reduced anti-atherogenic HDL.
- Dyslipoproteinemia involves abnormalities in lipoprotein synthesis and/or degradation.
- Dyslipidemia types include hypercholesterolemia, hypertriacylglycerolemia, and combined hypertriacylglycerolemia.
- Dyslipoproteinemia and atherosclerosis can lead to various health issues, including coronary artery disease, cerebrovascular disease, and peripheral artery disease.
High-Risk Cardiovascular Patients
- High-risk patients for cardiovascular disease include those with existing CAD, PAD, stroke, transient ischemic attack (TIA), diabetes, familial hyperlipoproteinemia, or premature atherosclerosis in family members.
- Target LDL cholesterol levels vary based on risk:
- Very high risk patients: <1.4 mM/L
- High-risk patients: <1.8 mM/L
- Moderate risk patients: <2.6 mM/L
- Low-risk patients: <3 mM/L (normal).
- Triglycerides should be <1.7 mM/l.
Dyslipidemia Management
- Non-pharmacological management involves lifestyle modifications focused on weight reduction and increased physical activity.
- Pharmacological treatments include:
- Statins (HMG-CoA reductase inhibitors): Inhibit liver cholesterol production, lowering VLDL, IDL, and LDL levels. Side effects include liver toxicity and rhabdomyolysis.
- Ezetimibe: Inhibits dietary cholesterol absorption. Side effects include diarrhea.
- Fibrates: Stimulate lipoprotein lipase, enhancing VLDL breakdown. Side effects include gallstones and hepatitis.
- Bile acid sequestrants: Bind bile acids in the gut, driving more cholesterol use, and lowering LDL with potential side effects including fat malabsorption.
- Niacin (nicotinic acid): In higher doses, it lowers VLDL and raises HDL levels. Side effects include hyperpigmentation and hyperuricemia.
- PCSK9 inhibitors: monoclonal antibodies targeting PCSK9 for treating very high risk. This is an expensive treatment.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the essential processes of cholesterol synthesis, its role in cell membranes, and the impact of HDL cholesterol on atherosclerosis. Understand how cholesterol functions as a precursor to steroid hormones and the protective mechanisms of HDL against cardiovascular diseases.
