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BLOOD LIPIDS1) Assess risk for cardiovascular

and cerebrovascular disease

2) Assess risk for pancreatitis

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Chylomicrons

TG

FattyAcids

Chylomicron remnant

is taken up by the liverLipoprotein

lipase

Excess

CBH

FATG

VLDL

TG

Fatty

Acids

Lipoprotein

lipase

IDLC

Lipoprotein

lipase

LDL C

Endocytosis viaLDL receptors

CCCCC

HDLTransfer of cholesterol

to LDL or IDL

Receptor

mediatedendocytosis

Receptor

mediatedendocytosis

Receptor

mediatedendocytosis

Receptor

mediatedendocytosis

1

2

3

4

5

6

7

8

9

1011

1213

14

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Hyperlipidemias

Primary

Caused by genetic defects in the synthesis

or metabolism of lipoproteins

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Role of LDL Oxidation in

Heart Disease

Oxidation

Oxidized LDL

Macrophage in

lining of bloodvessels

LDL

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Role of LDL Oxidation in

Heart Disease

Oxidation

Oxidized LDL

LDL

Foam CellBeginning stages in

plaque formation

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Hyperlipidemias

Primary

Caused by genetic defects in the synthesis

or metabolism of lipoproteins

Disorders precipitated by other disease

states, medications, or lifestyle

Secondary

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Effects of Lifestyle

Obesity Increases TG (primarily VLDL)

Also increases LDL

Sedentary Lifestyle Increases VLDL synthesis by the liver

Decreases the peripheral utilization of fat

and glucose All this increases TGs.

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Effects of Lifestyle

Exercise Increases HDL

Decreases LDL and VLDL

Diet Saturated fat and cholesterol increases

LDL

Moderate Alcohol Increases HDL (1 or 2 glasses of beer or

wine per day)

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NCEP Classification for TGs

< 200 mg/dl

200-400 mg/dl

400-1000 mg/dl

> 1000 mg/dl

Desirable

Borderline High

High

Very High

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Normal

Fasting

Serum

Serum

After a

Meal

After Overnight Refriferation

C

hylomicrons

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Normal Contributions to Total

Cholesterol

LDL

HDL

VLDL

60-70%20-30%

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Risk Factors for Heart Disease

High blood

cholesterol

Hypertension CV Disease

Smoking

Diet Obesity Diabetes

Atherosclerosis

Thrombosis(clots

in blood vessels)

DietBeing

Male

Genetic

predisposition

Aging

Lack of

exerciseLow

HDL

Dec 18, 2001

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NCEP Classification for

Cholesterol

< 200 mg/dl

200-239 mg/dl

> 240 mg/dl

Desirable

Borderline High

High

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Enzymatic Measurement of

Cholesterol

cholesterol

cholesterol oxidase

cholestene-4-ene-3-one + H2O2

HO O

H2O2 + reduced color indicator

peroxidase

2 H2O +oxidized color indicator

(now colored)

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Home Cholesterol Test

1

2

Contains

peroxidase

Moves sample into place

Opens buffer container

Cholesterol oxidase

Contains color indicator

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Reading the Result

Color indicator in the strip isoxidized by the H2O2 in the

presence of peroxidase

Read the peak height

from the scale on the

plastic case

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31.5

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Electrophoresis of Lipoproteins

OriginDirection of Migration

All Fractions

C

Fasting

Conditions

LDL VLDL

PreHDL

LDL VLDL HDL

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HDL-C by Precipitation

HDL

CHYLOMICRONS

VLDL

LDL

MnCl2 Heparin

centrifuge

precipitate

measure HDL chol.in supernatant

Precipitate all lipoproproteins except HDL

NCEP desirable:

> 35 mg/dl

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Measuring VLDL-C

Centrifuge

VLDL

HDL

&

LDL

Plastictube

PlasmaSlice tube

here

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Flow Chart

Receipt of Sample

TG Assay

TC Assay

HDL Assay

TC Assay

HDL Assay

Ultracentrifugation

Split tubes

VLDL fraction

Assay

TG < 250 mg/dl TG > 250 mg/dl

Use the Friedewald

Equation

Beta-Estimate Beta-Quant

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Direct LDL-C

LATEXBEAD

HDLLDL

VLDL

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NCEP Guidelines for LDL-C

< 130 mg/dl

130-159 mg/dl

> 160 mg/dl

Desirable

Borderline High

High

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I IIa IIb III IV V

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Non-lipid Tests for CVD Risk

Serum Homocysteine

Current Recommendation:

Analyze only in patients consideredat high risk due to cost.

Increase intake of 3 vitamins: B6 B12

and folate

Interferes with the formation of nitric oxide.

High-sensitivity C-reactive protein (hs-CRP)

A marker for systemic inflammation

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Lecithin/Sphingomyelin Ratio

L/S Indication

> 2/1

1.5-2/1

< 1.5/1

Lungs are mature

Transitional(50% risk of RDS)

Immature lungs(risk of RDS is great)

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END