Week 2

• What is atherosclerosis?

  Atherosclerosis is a progressive disease of the large arteries caused by local accumulation of lipids and fibrous elements together with inflammation.
• What initiates the inflammatory response in atherosclerosis?

  The inflammatory response is initiated by the oxidation of cholesterol molecules within the buildup of material in the arterial wall.
• What happens to monocytes in response to oxidized cholesterol in atherosclerosis?

  Monocytes travel to the damage site and are converted into macrophages that digest cholesterol molecules.
• How do foam cells contribute to plaque formation in atherosclerosis?

  Foam cells accumulate to form plaque as they digest cholesterol molecules.
• What role do smooth muscle cells play in the development of atherosclerosis?

  Smooth muscle cells multiply and contribute to the formation of a fibrous cap covering the plaque.
• What can happen to the fibrous cap over time in atherosclerosis?

  The fibrous cap may erode and break open, releasing plaque into the bloodstream.
• What are the potential consequences of atherosclerosis on blood flow?

  Atherosclerosis can narrow the passageway through the artery, reducing blood flow and oxygen supply to organs.
• What is the main type of cholesterol involved in atherosclerosis?

  The main type of cholesterol involved in atherosclerosis is low-density lipoprotein cholesterol (LDL-C).
• What are the three main layers of a normal artery wall?

  The three main layers are the tunica intima, tunica media, and tunica adventitia.
• What are some risk factors for atherosclerosis?

  Risk factors include smoking, high blood pressure, diabetes, and high cholesterol.
• How does elevated LDL-C contribute to atherosclerosis?

  Elevated LDL-C can penetrate the damaged arterial wall and contribute to plaque formation.
• How do genetics and lifestyle contribute to atherosclerosis?

  Atherosclerosis is thought to be affected equally by both genetics and environmental/lifestyle factors.
• What physiological roles does cholesterol play in the human body?

  Cholesterol is involved in cell membrane structure, steroid hormone synthesis, bile acid production, and absorption of lipid-soluble vitamins.

  
• How is cholesterol transported in the bloodstream?

  Cholesterol is transported in the bloodstream by lipoproteins.
• What are lipoproteins composed of?

  Lipoproteins are composed of a central core lipid surrounded by polar phospholipids and proteins.
• What is the role of apolipoproteins in lipoproteins?

  Apolipoproteins mediate the docking and delivery of lipoproteins and their contents to specific receptors and enzymes on target cells.

  
• What happens when liver cells are deficient in cholesterol?

  Liver cells express LDL receptors that bind to LDL lipoproteins for internalization.
• What is the primary goal of drug therapy in dyslipidemia?

  The primary goal is the reduction of LDL-C levels in the bloodstream.
• What are some examples of statin drugs?

  Examples of statin drugs include simvastatin, lovastatin, pravastatin, atorvastatin, and rosuvastatin.
• How do statins help in reducing cholesterol levels?

  Statins inhibit HMG-CoA reductase, reducing cholesterol synthesis in the liver.
• What is the relationship between LDL receptors and cholesterol levels in the bloodstream?

  Increased expression of LDL receptors leads to greater uptake of LDL-C from the bloodstream, reducing its levels.

  
• What are some risk factors for cardiovascular disease (CVD)?

  Risk factors for CVD include smoking, elevated blood pressure, dyslipidemia, diabetes, and increasing age.
• What limitations exist in CVD risk scores?

  CVD risk scores can overestimate or underestimate someone's risk and cannot account for all contributing factors.
• Why is waist circumference a better predictor of cardiovascular risk compared to BMI?

  Waist circumference is a better predictor because it measures central obesity, which is associated with increased cardiovascular risk.
• What are the stages of development of atherosclerosis plaque?

  1. Damage to the endothelium
  2. Accumulation of lipids and waste products
  3. Oxidation of cholesterol
  4. Inflammatory response and monocyte recruitment
  5. Conversion of monocytes to macrophages
  6. Formation of foam cells
  7. Plaque accumulation and arterial wall thickening
  8. Smooth muscle cell proliferation and fibrous cap formation
  9. Potential erosion of the cap and plaque release into circulation

  
• What are the factors contributing to dyslipidemia?

  • Primary genetic causes (mutations affecting lipid metabolism)
  • Sedentary lifestyle
  • High intake of saturated fat, cholesterol, and trans fat
  • Low HDL cholesterol due to smoking, anabolic steroids, and medications

  
• What are the mechanisms of action for drugs used in dyslipidemia management?

  • Statins: Inhibit HMG-CoA reductase to reduce cholesterol synthesis
  • Ezetimibe: Reduces cholesterol absorption in the intestine
  • Fibrates: Lower triglyceride levels
  • Bile acid binding resins: Bind bile acids to reduce cholesterol levels
  • Monoclonal antibodies: Target PCSK9 to increase LDL receptor availability

  
• What are the physiological roles of cholesterol in the body?

  • Cell membrane structure and fluidity
  • Synthesis of steroid hormones
  • Production of bile acids
  • Absorption of lipid-soluble vitamins

  
• What are the types of lipoproteins and their functions?

  • Chylomicrons: Transport lipids from intestinal absorption to tissues
  • Very Low-Density Lipoproteins (VLDL): Transport triglycerides and cholesterol from the liver to tissues
  • Low-Density Lipoproteins (LDL): Carry cholesterol to tissues and contribute to plaque formation
  • High-Density Lipoproteins (HDL): Transport surplus cholesterol back to the liver for storage and excretion

  
• What are the risk factors for atherosclerosis?

  • Smoking
  • High blood pressure
  • Diabetes
  • High cholesterol
  • Elevated LDL-C
  • Reduced HDL-C
  • Obesity
  • Physical inactivity
• What are the limitations of BMI as a measure of obesity?

  • Influenced by age, gender, and ethnicity
  • May misclassify fit individuals as overweight/obese
  • Less accurate for older populations with reduced muscle mass

  
• What is the significance of central fat measurement in assessing cardiovascular risk?

  • Central fat is associated with increased cardiovascular risk
  • Waist circumference is a better predictor than BMI
  • Waist-to-hip ratio may provide additional insights

  
• What does BMI stand for?

  Body Mass Index
• Why are BMI estimates considered limited?

  They cannot account for all factors contributing to someone's cardiovascular disease (CVD) risk
• What are the limitations associated with BMI?

  • Influenced by age, gender, and ethnicity
  • Fit/muscular individuals may appear overweight
  • Aged populations may have less muscle mass
  • Ethnic group data is primarily based on Caucasian populations

  
• What is central fat associated with?

  Increased cardiovascular risk
• How is waist circumference used in assessing cardiovascular risk?

  It is a measure of central obesity and a better predictor of cardiovascular risk compared to BMI
• What are the cutoff measurements for waist circumference indicating increased cardiovascular risk?

  Greater than 80 cm for females and greater than 90 cm for males
• What do overweight and obesity refer to?

  Excessive fat accumulation that may impair health and increase cardiovascular risk
• What is obesity classified as?

  A complex, chronic, relapsing condition associated with increased metabolic and cardiovascular risk