WEEK 5: Lipid alterations and CV disorders Flashcards
what is the precursor molecule for hormones?
cholesterol
where are lipoproteins found?
blood plasma
function of lipoproteins?
Lipoproteins carry cholesterol and triglycerides to cells in the body
lipoprotein structure?
outer layer - phospholipids, cholesterol, protein
neutral lipid core of cholesterol esters
what happens to chylomicrons in the liver?
turned into VLDL and transport
VLDL
made in liver
transports lipids to tissues
LDL
carry cholesterol to tissues
chylomicrons
v large v low density
chylomicrons
v large v low density
major classes of lipoproteins
chylomicrons
VLDL
LDL
HDL
what is the composition of a low density lipid?
high fat percentage
total cholesterol, healthy level
Levels below 200 mg/dL (5.2 mmol/L)
LDL cholesterol, healthy level
Levels below 130 mg/dL (3.4 mmol/L)
HDL cholesterol, healthy level?
Levels above 40 mg/dL (1 mmol/L) in men and above 50 mg/dL (1.3 mmol/L) in women
why is a healthy level of cholesterol required?
HDL acts to scavenge extra cholesterol
what is measured in a fasting lipid profile?
Total cholesterol, HDL, and triglycerides are measured
what is the Friedewald formula?
[LDL-chol] = [Total chol] - [HDL-chol] - ([TG]/2.2) where all concentrations are given in mmol/L
what are apolipoproteins?
Apolipoproteins are theproteincomponent of lipoproteins, complexes that transport lipids throughout the bloodstream.
what are the 2 forms of apolipoprotein?
There are two forms of apolipoprotein B: apo B-100 and apo B-48
where is apo B-100 made?
liver
where is apo B-48 made?
intestines
understand slide 13 !
understand and be able to summarise slide 14!
what does obesity aggravate?
dyslipidemia, hypertension, insulin resistance
what is xanthelasmas?
a type of xanthoma, are raised, yellowish macules that typically appear around the medial canthus (inner corner of eye). Involvement can extend to the eyelids or skin immediately below the eye.
what is xanthoma?
Xanthoma is a skin condition in which certain fats build up under the surface of the skin.
what is lipemia retinalis?
Lipemia retinalis a condition in which lipemic blood causes opalescence of retinal arterioles.
what is CVD?
Cardiovascular disease (CVD) is a general term for conditions affecting the heart or blood vessels.
what are the 4 main types of CVDs?
- Coronary Heart Disease – angina, heart attack, heart - failure
- Stroke and transient ischaemic attack (TIA)
- Peripheral arterial disease
- Aortic disease
how many deaths are caused by CVDs?
> 17 million deaths globally each year
how can someone manage the risk of CVD?
- diet - replace saturated fats with complex carbs, monosaturated and polyunsaturated fats (vegetable and seafood). Increase fruit and veg intake
- increase physical excerise
- lower blood pressure
- change behavioural risk factors, eg smoking
what is thrombosis?
Thrombosis occurs when blood clots block veins or arteries
what is atherosclerosis?
Atherosclerosis is the build up of fats, cholesterol and other substances in and on the artery walls. This build up is called plaque.
dyslipidemia
abnormal lipoprotein levels (LDL and HDL) in association with an increased risk of cardiovascular disease
hyperlipidemia
elevated blood lipid levels (total cholesterol,LDL, triglycerides)
hypercholesterolemia
elevated total cholesterol
how does adipose tissue link to cardiovascular disease?
slide 33
how are adipoctyes different in obese tissue?
they produce pro-inflammatory adipokines, increase inflammation and oxidative stress
slide 34
what was the first adipokine discovered?
leptin
what does leptin do?
It mainly decreases appetite, increases energy expenditure, and regulates glucose homeostasis independently of insulin action through hypothalamic and sympathetic signalling.
what is leptin?
Pro-inflammatory cytokine - activates monocytes, leukocytes, and macrophages to produce IL-6, TNFα, and IL-12
what happens to leptin during obesity?
Leptin resistance develops. Leads to hyperleptinemia, which is a risk factor of coronary heart disease
slide 37
briefly describe the 4 stages of atherosclerosis
Stage 1: Endothelial damage and immune response
Stage 2: Fatty streak
Stage 3: Plaque growth
Stage 4: Plaque rupture and thrombosis
how does thromboplastin contribute to the formation of fibrin?
thromboplastin converts prothrombin to produce thrombin. Thrombin converts fibrinogen into fibrin.
what are the 2 types of thrombosis? What does the name depend on?
2 categories based on location:
- Arterial thrombosis
- Venous thrombosis
what is a thrombus composed of?
- Fibrin
- Platelets
- Red blood cells
- Leukocytes
- Cholesterol crystals
what is the best way to test for diabetes?
to test glycosylated hemoglobin levels
how is acute myocardial infarction quickly diagnosed according to WHO?
chest pain
ECG
cardiac markers (enzymes)
what is aspartate transaminase?
a cardiac marker that can indicate liver damage
go over slide 48/49
lactate dehydrogenase
what is the function of lactate dehbhbhsjb
turns pyruvate into lactate and vice versa
slide 50-64 all based on CK-MB