30. Lipids and lipoproteins in the blood plasma
Parameter | Sample | Reference range |
---|---|---|
Cholesterol | Serum | 4,0 – 5,6 mM |
LDL | Serum | 0,0 – 3,4 mM |
HDL | Serum | 0,9 – 1,7 mM |
- Analysis of lipids
- Enzymatic assay
- Cholesterol
- HDL, LDL
- FFA
- Triglycerides
- Immunoassay
- ApoA1
- ApoB
- Lp(a)
- Lipoprotein electrophoresis
- Ultracentrifugation – sorted after density
- Enzymatic assay
- Cholesterol
- Component of cell membrane
- Precursor of steroid hormones and bile acids
- Triglycerides
- Energy store
- Risk factor for CVD, acute pancreatitis
- HDL
- Contains mostly protein and phospholipid
- Transports cholesterol back to liver from peripheral tissues
- Negative risk factor for CVD
- LDL
- Contains mostly cholesterol
- Transports cholesterol from liver to peripheral tissues
- Risk factor for CVD
- Small, dense LDL
- Greater atherogenic potential than other LDL subtypes
- Less affinity to LDL receptor
- Higher endothelial permeability
- VLDL
- Contains mostly triglycerides
- Transports triglycerides from liver to peripheral tissues
- Lipoprotein(a)
- LDL-like particle
- Contains mostly cholesterol
- Increased level -> increased risk for CVD, atherosclerosis
- Independent predictor of CVD
- Recommended to be tested in people with moderate or high risk for CVD
- Chylomicron
- Contains mostly triglycerides
- Transports dietary triglycerides to peripheral tissues and liver
- Nonfasting lipid panel
- Measures HDL and total cholesterol
- Screening every 5 years from around 40 y old, from 20y if high risk
- Fasting lipid panel
- Measures HDL, total cholesterol, triglycerides, LDL
- LDL can be calculated: LDL = TC – HDL – (TG/5)
- Hereditary dyslipidaemias
- Familial hypercholesterolaemia
- Mutated LDL receptor
- High risk for AS and xanthoma
- Familial combined hyperlipidaemia
- Decreased LDL receptor
- Familial hypertriglyceridaemia
- Can cause pancreatitis
- Familial hypercholesterolaemia
- Metabolic syndrome
- Definition: 3 or more of the following:
- Insulin resistance
- Hypertension
- Hypertriglyceridaemia
- Low HDL
- Abdominal obesity
- Definition: 3 or more of the following: