lipids Flashcards
-building blocks of lipids
-hydrocarbon chains with a terminal coo-groups
Fatty Acids
-3 fatty acids molecules attached to one molecule of glycerol by ester bonds
-serves as main storage form of energy, insulator, shock absorber and integral part of cell membrane
TRYGLYCERIDES
-Similar to tryglycerides except that the third position on the glycerol backbone contaons a phospholipids head group
-contains polar and non-polar end
-constituent of cell membrane
PHOSPHOLIPIDS
Serve as part of cell membranes and as parent chain of cholesterol based hormones, e.g aldosterone, cortisol and the sex hormones
Exists in forms
CHOLESTEROL
App. 70% of TC
Cholesterol esters
app. 30% TC
Free Cholesterol
GENERAL LIPOPROTEIN STRUCTURE: Typical _________ in shape with sizes ranging from 10-1200 nm
SPHERICAL
GENERAL LIPOPROTEIN STRUCTURE: composed of lipids and proteins, called ______________
APOLIPOPROTEINS
GENERAL LIPOPROTEIN STRUCTURE: the various lipoproteins were originally separated through ______________
ULTRACENTRIFUGATION
-located on the structure of lipoprotein particles
-maintain structural integrity of lipoproteins
-serves as ligands for cell receptors
APOLIPOPROTEINS
TYPES OF MAJOR LIPOPROTEINS:
2nd largest, 2nd least dense
2nd highest TAG content
causes fasting hyperlipidemic turbidity
FUNCTION
transports endogenous (hepatic) tryglycerides
VLDL
TYPES OF MAJOR LIPOPROTEINS:
produced by the lipolysis of VLDL
small lipoprotein
directly related to risk of Coronary Heart disease
highest cholesterol content
FUNCTION
transport the Cholesterol to peripheral tissue
LDL-LOW DENSITY LIPOPROTEIN
TYPES OF MAJOR LIPOPROTEINS:
Smallest, but densest
highest protein content
FUNCTION
Reverse transport cholesterol
HDL-HIGH DENSITY LIPOPROTEIN
MINOR/ABNORMAL LIPOPROTEINS:
also known as FLOATING BETA-LIPOPROTEIN
seen in familial dysbetalipoproteinemia
BETA-VLDL
MINOR/ABNORMAL LIPOPROTEINS:
also known as sinking pre-beta lipoproteinemia
LDL-like particle
LP (A)
MINOR/ABNORMAL LIPOPROTEINS:
seen in biliary cholestasis, familial LCAT deficiency
LPX
BETA-VLDL is also known as?
FLOATING BETA-LIPOPROTEIN
SPECIMEN CONSIDERATION:
Fasting = _____ hrs
12 HOURS
CHOLESTEROL MEASUREMENTS:
Definitive method
ISOTOPE DILUTION MASS SPECTROMETRY (IDMS)
glacial acetic acid
sulfuric acid
acetic anhydride
LIEBERMANN-BURCHARD REAGENT
TRIGLYCERIDE MEASUREMENTS:
Hydrolysis of glycerol is accomplished using alcoholic KOH
Oxidation of glycerol by periodic acid, forming formaldehyde and formic acid
Formaldehyde combines with a variety of reagents:
CHEMICAL METHOD
TRIGLYCERIDE MEASUREMENTS:
New reference method for triglyceride measurements, involve the hydrolysis of fatty acids on triglycerides and the measurement of glycerol.
GC-MS METHOD
LIPOPROTEIN MEASUREMENTS:
Range in density observed among lipoprotein classes is a function of lipid and protein content and enables fractionation by density using centrifugation.
ULTRACENTRIFUGATION
LIPOPROTEIN MEASUREMENTS:
Takes advantage of difference in size and change
ELECTROPHORESIS
LIPOPROTEIN MEASUREMENTS:
Depends on particle size, charge and differences in the apolipoprotein content; primarily used in research labs only
Uses polyanions (heparin sulfate, dextran sulfate and phosphotungstate) and divalent cations such as magnesium, calcium and manganese e.g. HDL - dextran sulfate + magnesium
CHEMICAL PRECIPITATION
LIPOPROTEIN MEASUREMENTS:
Uses antibodies specific to apolipoproteins to bind and separate lipoprotein classes.
IMMUNOASSAYS
LIPOPROTEIN MEASUREMENTS:
Takes advantages of size differences in molecular sieving methods or composition in affinity methods e.g. gel chromatography or affinity chromatography.
CHROMATOGRAPHIC METHODS
SUMMARY OF TEST AND END COLOR:
Liebermann-Burchardt reaction
end color - Cholestadienyl Monosulfonic Acid
GREEN COLOR
SUMMARY OF TEST AND END COLOR:
Salkowski Reaction
end color - Cholestadienyl Disulfonic Acid
RED COLOR
SUMMARY OF TEST AND END COLOR:
Abell, Levey and Brodie Mtd.
GREEN COLOR
SUMMARY OF TEST AND END COLOR:
Van Handel and Zilversmith Mtd
BLUE COLOR COMPOUND
(LDL-Cholesterol) = (total Cholesterol) - (HDL-C) - (Plasma TAG) / _______
2.175
(LDL-Cholesterol) = (total Cholesterol) - (HDL-C) - (Plasma TAG) / 2.175
FRIEDWALD CALCULATION
CLINICAL CORRELATIONS:
A narrowing and hardening of the arteries, caused by plaque formation, leading to reduced circulation.
ATHEROSCLEROSIS
CLINICAL CORRELATIONS:
It is an autosomal dominant disorder caused by defective or deficient LDL receptors
FAMILIAL HYPERCHOLESTEROLEMIA (TYPE 2A)
CLINICAL CORRELATIONS: Involves accumulation of plasma VLDL rich in cholesterol
FAMILIAL DYSBETALIPOPROTEINEMIA (TYPE 3 HYPERLIPOPROTEINEMIA)
CLINICAL CORRELATIONS:
(Basses-Kornzweig Syndrome) defective apo B synthesis
Characterized by cerebellar ataxia, acanthocytosis, fat malabsorption
ABETALIPOPROTEINEMIA
CLINICAL CORRELATIONS:
It is due to apo-B deficiency resulting from point mutation in apo-B
Decreased: LDL cholesterol and Total Cholesterol
HYPOBETALIPOPROTEINEMIA
CLINICAL CORRELATIONS:
inherited disorder or lipid metabolism in which there are accumulation of sphingomyelin ib the bone marrow, spleen and lymph nodes.
NIEMANN-PICK DISEASE (LIPID STORAGE DISEASE)
CLINICAL CORRELATIONS:
is a rare autosomal recessive disorder characterized by complete absence of HDL due to mutation.
TANGIER DISEASE
CLINICAL CORRELATIONS:
It results to inability to clear chylomicron particles, creating the classic “type 1” chylomicronemia syndrome.
LIPOPROTEIN LIPASE DEFICIENCY
CLINICAL CORRELATIONS:
Due to mutation in the LCAT gene
Fish-eye disease is milder form of LCAT deficiency
LCAT DEFICIENCY
CLINICAL CORRELATIONS:
It is an inherited neurodegenerative disorder of lipid metabolism characterized by a deficiency of the enzyme hexosaminidase A, which results in the accumulation of sphingolipids in the brain
TAY-SACHS DISEASE
CLINICAL CORRELATIONS:
This syndrome is distinct from abetalipoproteinemia, as only apob-48 appears to be affected.
Clinical finding: fat malabsorption and low levels of plasma lipids
CHYLOMICRON RETENTION DISEASE (ANDERSON’S DISEASE)
CLINICAL CORRELATIONS:
It is a recessive disorder wherein plant sterols are absorbed and accumulate in plasma and peripheral tissues.
SITOSTEROLEMIA
Other term for CHYLOMICRON RETENTION DISEASE
ANDERSON’S DISEASE
Other term for CHYLOMICRON RETENTION DISEASE
ANDERSON’S DISEASE
