Lipids

What are the 3 types of lipids found in the blood?

1. Triglycerides

2. Cholesterol

3. Long Chain Fatty Acids (LCFAs)

The building block for Triglycerides is what?

LCFAs

What are the 2 sources of LCFAs?

1. Absorbed in the intestinal tract

2. Produced from glucose/acetate

The concentration of triglycerides in blood circulation depends on the balance between what 3 things?

1. Triglyceride absorption from the small intestine

2. Uptake by cells

3. Synthesis/secretion by hepatocytes

What is LPL?

Lipoprotein lipase (LPL) is a crucial enzyme that breaks down triglycerides in the bloodstream (from VLDL and chylomicrons) into free fatty acids and glycerol

What is Lipolysis?

The process of converting stored triglycerides into free fatty acids and glycerol which is then released into the blood for energy

What 2 blood lipids are frequently measured?

1. Cholesterol

2. Triglycerides

What are the 2 sources of cholesterol?

1. Absorbed from the diet/intake

2. Production in the liver

How do lipids travel from the site of origin (intestine/liver) to their destination (storage/cells for energy usage)?

They are attached to proteins and form complexes known as Lipoproteins

The production and activity of LPL depends on _______ as it allows LPL to “float” from the inner to outer surface of the cell membrane so that it can come into contact with plasma lipoproteins.

Insulin

What is the importance/uses of Cholesterol?

1. Important part of cell membranes

2. Used by various organs to synthesize hormones

Define Hyperlipidemia

Increased concentrations of cholesterol, triglycerides, lipoproteins, NEFAs (or combination of the 4)

T/F: Hyperlipidemia may result in lipemia

True

What is Lipemia? Is it a concern?

• The presence of excessive fat particles (lipids), particularly triglycerides, in the blood, causing plasma or serum to appear milky, cloudy, or opaque

• Lipemia can interfere with the accurate measurement of B.W analytes

  • Hgb, MCHC, Total Protein, Platelet, bilirubin, electrolytes, etc.

What is the main lipid measured in a S.A bloodwork panel?

Cholesterol

Hyperlipidemia can either be _____ or ______, what is the difference?

• Physiological

  • Post-Prandial

    • The patient has just eaten a meal, and that is why glucose is elevated

• Pathological

  • 1° or 2°

  • Caused by a pathogen or disease

__________ Hyperlipidemia is the most common cause in S.A

Physiological

**What 2 dogs breeds are predisposed to 1° idiopathic hyperlipidemia?**

1. Miniature Schnauzers

2. Shetland Sheepdogs

Bc there is high cholesterol down in MSSSissippi

What is more common, 1° or 2° pathological hyperlipidemia?

• 2°

  • 1° is an inherited defect in lipid metabolism, 2° is acquired

What are 4 examples of 1° Hyperlipidemia?

1. Idiopathic hyperlipidemia of miniature schnauzers

2. Idiopathic hyperlipidemia of Shetland Sheepdogs

3. Primary Hyperchylomicronemia

   1. Type III LPL deficiency in cats

4. Idiopathic hypercholesterolemia

What are the 9 possible causes of Hyperlipidemia in dogs?

1. Hypothyroidism

2. Hyperaddrenocorticism

3. D.M

4. Pancreatitis

5. Nephrotic syndrome or protein losing nephropathy

6. Cholestasis

7. Gram-negative sepsis

8. Consumption of a high fat diet

9. Phenobarbital-associated (just dogs)

Of the previous 9 causes of hyperlipidemia, which 2 are rarely the culprit of 2° Hyperlipidemia in cats?

1. Hypothyroidism

2. Hypoadrenocorticism

Which species/type of horses are prone to Equine Hyperlipidemia?

Miniature horses/Donkeys

Good differential chart to systematically work through Hyperlipidemia cases

T/F: Hypolipidemia (Hypocholesterolemia) is a very common clinical finding in small animal medicine

False, its relatively uncommon

What are 5 differentials for Hypolipidemia?

1. Hepatic Disease (Especially hepatic insufficiency or dysfunction)

2. Protein-losing enteropathy

   1. Since lipids bind to proteins (lipoproteins) in order to travel

3. Hypoadrenocorticism

4. Severe malnutrition or prolonged decreased dietary intake

5. Hematopoietic neoplasia

T/F: Damage to the liver always causes Hypolipidemia

False, the liver is very complex, some diseases can cause hyperlipidemia, while others can cause hypolipidemia