2. Outline
• Definition
• Structure & function of blood vessels
• Endothelium & function assessment
• About atheriosclerosis
• Atherosclerosis tests
• Anti-atherosclerosis assay
• Summary of journal
2
3. Definition
• Arteriosclerosis – walls of the arteries become
thick and stiff, restricting blood flow to organs
& tissues
• Atherosclerosis – buildup of fats and
cholesterol in artery walls (plaques)
• Cholesterol - a sterol (C27H45OH) found in all
animal tissues, blood, bile, and animal fats
• Plaques – Will become blood clot when burst
3
4.
5. Function of blood vessels
1) Arteries
• carries blood away from the heart
• has three layers, muscular and elastic tubes that can withstand large
pressure
• carries oxygen-rich blood to cells
2) Capillaries
• join the blood flow from the arterials (small arteries) to the venules
(small veins)
• exchange of nutrients and gases occur at the cellular level because the
capillaries are only one cell thick
3) Veins
• carry blood to the heart
• larger in diameter
• contain valves to assist in moving the blood back to the heart
6.
7.
8. Endothelial function assessment
• Vascular tone
– vascular reactivity
– vasocontrictors: ET-1
– vasodilators: nitric oxide products
• Markers of endothelial activation
– adhesion molecules (VCAM, ICAM, selectin)
• Markers of coagulation/ fibrinolysis
– PAI-1, tPA, fibrinogen, thrombomodulin, VWF
• Markers of inflammation
– CRP, TNF-α, IL-1, IL-6
• Hormones and metabolic products with known vascular effects
– Adinopection, FFA
9. Role of VCAM-1 & ICAM-1
• VCAM-1 promotes monocyte adhesion and
accumulation on the vessel wall at sites that
are prone to developing atherosclerotic
lesions
• A study in 2002 (Kitagawa) suggest that level
of sICAM-1 is closely related with the severity
of atherosclerosis and cardiovascular events
10. Types of arteriosclerosis
• There are three main forms of arteriosclerosis:
– atherosclerosis, the most common type, in which plaques
of fatty deposits form in the inner layer (tunica intima) of
the arteries;
– Mönckeberg's arteriosclerosis, called also medial calcific
sclerosis because of involvement of the middle layer
(tunica media) of the arteries, where there is destruction
of muscle and elastic fibers and formation of calcium
deposits;
– arteriolar sclerosis or arteriolosclerosis, which is marked by
thickening of the walls of arterioles
13. How does antioxidant relate to
atherosclerosis?
• Oxidized LDL is cytotoxic to the endothelial cells
• Accumulation of LDL in macrophages will lead to
formation of foam cells
• Foam cells is the key component of fatty streak
• Antioxidant action which reduces the production
of free radicals, decreasing the oxidized LDL and
alleviating the subsequent damage to the heart
tissue
15. How to prevent atherosclerosis?
• By taking dietary micronutrients to prevent
oxidation of LDL:
– E.g α-tocopherol, β-carotene, ascorbate, coenzyme
Q10
• By taking food that lowers your cholesterol
– Oatmeal, oat bran and high-fiber foods
– Fish (with high omega-3 fatty acids)
– Walnuts, almonds and other nuts (polyunsaturated)
– Olive oil
– Food with plant sterols or stanols (to block absorption
of cholesterol)
15
16. 16
Test Principle Measurement
Histological analysis
Fatty streak
analysis
To observe
atherosclerotic
lesions, thickening of
tunica intima
Electron microscope
VCAM-1 & ICAM-1
marker
Expression of
VCAM-1 preceded
lesion formation
when exposed to
plasma cholesterol
Enzyme-Linked
Immunosorbent Assay
(ELISA)
17. Type of
analysis
Animal Result Positive
control
Unit &
measurem
ent
Author
(year)
Histological
analysis
(transmission
electron
photograph)
New Zealand
white rabbits
(abdominal
aorta)
Percentage
of lesion
area
reduced
Simvastatin % Amran
(2010)
Rabbit Enzyme-
Linked
Immunosorbent
Assay (ELISA)
New Zealand
white rabbits
(blood
sample via
marginal ear
vein)
Reduction
in VCAM-1,
ICAM-1 and
CRP
Simvastatin mg/kg Amran
(2011)
Fatty streak
analysis
New Zealand
white rabbits
(abdominal
aorta)
Reduction
of area of
fatty streak
Simvastatin -
(neointimal
area)
Amran
(2012)
Summary from journal
18. Type of
analysis
Organ/cell Result Positive
control
Unit &
measure
ment
Author
(year)
Nitric oxide
Synthase
Colorimetric
Assay
Human
umbilical vein
endothelial
cells (HUVEC)
Increased
in eNOS
mRNA
expression,
protein
level and
NO
production
- nmoles/
mL/min
μM
Ugusman
(2010)
Quantitative
reverse
transcription
polymerase
chain
reaction (qPCR)
New Zealand
white rabbits
(abdominal
aorta)
Decreased
mRNA
expression
of ICAM-1
& Nox4
Increase in
SOD1,
catalase
and GPx
- mg/kg Ugusman
(2011)
Summary from journal
19. ‘FUN’ QUIZ: Why choose the ear part to take
blood samples from rabbit?
20. Answer
• Lesser adverse effects
– Bruising/haemorrhage <1%
– Infection <1%
• Up to eight samples in any 24-hour period,
depending on sample volume
• Up to 0.5 - 10 ml, depending on the size and
strain of the rabbit
• One of the least invasive method in taking
blood sample
