Lipid Metabolism and Disorders Quiz

Study Notes

Lipid Metabolism

Fats are crucial for diet; they enhance taste and texture, serve as a primary energy source, and facilitate the absorption of essential vitamins.
Fats can be converted to other important molecules such as prostaglandins.

Lipoprotein Overview

Lipoproteins are complex particles with a hydrophobic core of non-polar lipids, essential for lipid transport in the body.
Functions include:
- Absorption and transport of dietary lipids in the small intestine.
- Transporting lipids from the liver to peripheral tissues.
- Facilitating reverse cholesterol transport from peripheral tissues back to the liver and intestine.

Lipid Digestion

Chylomicrons are large particles containing triglycerides and cholesterol, surrounded by a phospholipid membrane with apolipoproteins for solubility in body fluids.
Lipoprotein Lipase (LPL) is crucial for hydrolyzing triglycerides, enabling the release of free fatty acids.

Dyslipidemia

Characterized by abnormal blood levels of cholesterol, triglycerides, and/or lipoproteins, leading to hyperlipidemia.
Major types include:
- Hyperlipidemia (HLD): Refers to elevated cholesterol, triglycerides, or lipoproteins.
- Hypercholesterolemia: Total cholesterol levels exceed 200 mg/dL.
- Hypertriglyceridemia: Elevated triglycerides above 150 mg/dL.
Prevalence is higher with age, and men are more affected than women.
It is a significant risk factor for coronary artery disease and atherosclerosis.

Causes of Dyslipidemia

Primary (Familial): Resulting from polygenic inheritance.
Secondary (Acquired): Associated with:
- Lifestyle factors such as obesity, smoking, and heavy alcohol consumption.
- Systemic illnesses including diabetes mellitus and hypothyroidism.
- Certain medications like thiazide diuretics and oral estrogens.

Atherosclerosis

The fatty streak phase includes the adhesion of blood leukocytes to activated endothelial cells.
During plaque progression, a fibrous cap forms, composed of smooth muscle cells, collagen, proteoglycans, and elastin, leading to stable plaques.
Smooth muscle cells migrate and stimulate extracellular matrix production, further contributing to plaque stability.

Fredrickson Classification of Inherited Hyperlipidemias

Type I HLP: Deficiency in ApoC-II, affecting the activity of lipoprotein lipase and triglyceride hydrolysis.
Type II HLP: Involves Apolipoprotein B-100, essential for VLDL assembly and secretion, with the PCSK9 gene regulating cholesterol levels.

Description

Test your knowledge on lipid metabolism and lipid disorders with this quiz. Covering topics such as lipoprotein classes, lipid digestion, and dyslipidemia, this quiz is designed for students in the Department of Pathology. Prepare to explore various lipid disorders and the Fredrickson classification.