Dr. S. Nishan Silva (MBBS). Atherosclerosis Functions of the Plasma Lipoproteins...
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Transcript of Dr. S. Nishan Silva (MBBS). Atherosclerosis Functions of the Plasma Lipoproteins...
Dr. S. Nishan Silva
(MBBS)
Atherosclerosis
Functions of the Plasma Lipoproteins
• Chylomicron—Transport of dietary triglyceride
• VLDL—Transport of endogenous triglyceride
• IDL—LDL precursor• LDL—Major cholesterol transport
lipoprotein• HDL—Reverse cholesterol transport
HyperlipidemiasHyperlipidemias• Elevated blood triglycerides and/or
cholesterol• Lipoproteins found in blood
Chylomicrons = postprandial dietary fat Very-low-density lipoproteins (VLDL) = lipid being
transported from liver to peripheral tissue Low-density lipoproteins (LDL) = transport of
cholesterol High-density lipoproteins (HDL) = reverse
transport of cholesterol, tissues to liver• Type of hyperlipidemia depends upon
portion of particles present
• Elevated blood triglycerides and/or cholesterol
• Lipoproteins found in blood Chylomicrons = postprandial dietary fat Very-low-density lipoproteins (VLDL) = lipid being
transported from liver to peripheral tissue Low-density lipoproteins (LDL) = transport of
cholesterol High-density lipoproteins (HDL) = reverse
transport of cholesterol, tissues to liver• Type of hyperlipidemia depends upon
portion of particles present
ATP III Classifications/GuidelinesATP III Classifications/Guidelines
TestTest LevelLevel Health ImpressionHealth Impression
Total Total
CholesterolCholesterol
<200 mg/dl<200 mg/dl200-239 mg/dl
>240 mg/dl
DesirableDesirableBorderline High
High
LDLLDL
CholesterolCholesterol
<100 mg/dl<100 mg/dl
100-129 mg/dl100-129 mg/dl130-159 mg/dl160-189 mg/dl
>190 mg/dl
OptimalOptimal
Near OptimalNear OptimalBorderline High
HighVery High
HDLHDL
CholesterolCholesterol<40 mg/dl
>60 mg/dl>60 mg/dlLow
HighHigh
TriglyceridesTriglycerides
<150 mg/dl<150 mg/dl150-199 mg/dl200-499 mg/dl
>500 mg/dl
NormalNormalBorderline High
HighVery High
Blood PressureBlood Pressure≥ 140 mm Hg (systolic BP)≥ 90 mm Hg (diastolic BP)
High High
CARDIOVASCULAR DISEASE ~ TREATMENT
– Primary ~ preventivemajor disease reduction benefit occurs at this stage ~BUT~ only if therapy implemented
– Secondarymorbidity and mortality benefits from therapy is well below that of primary prevention
Cardiovascular Risk Factors• Category I—cigarette smoking, LDL
cholesterol, high-fat diet, hypertension• Category II—diabetes mellitus, physical
inactivity, HDL cholesterol, TG, obesity• Category III—psychosocial factors,
lipoprotein a, homocysteine• Category IV—age, male gender, low
socioeconomic status, family history
CVD ~ Endothelial Dysfunction
• Critical elements include:–Genotype ~ –Intrauterine & perinatal nutrition &
growth–Dyslipidemia ~ –Insulin Resistance and obesity–Diet–Exercise ~ Sedentary lifestyle vs
regular exercise–Smoking & environmental pollutants
CardioVascular Diease:
TREATMENT • Focus of primary and secondary preventive therapy is to:
– Reduce cholesterol levels ~• Statins ~ PLUS ~ diet
– Reduce platelet activity• Aspirin ~ PLUS ~ Omega-3-Essential fatty Acids
– Reduce Inflammation ~• Statins + aspirin – diet?
– Improve Endothelial Dysfunction• Statins – diet?
– Control blood pressure• ACE inhibitors, ACE receptor inhibitors - Diet
• chlorthiazides, calcium-channel blockers
What about improving cardiac & vascular cell
metabolism?
Key Emphasis Components of a Heart - Healthy Diet
Division of Lung DiseasesNHLBI, NIH
Limit salt (sodium) Limit salt (sodium) Limit CholesterolLimit Cholesterol
Regular Physical Regular Physical ActivityActivity
Limit Saturated FatLimit Saturated Fat
Moderation, Variety & Nutrient AdequacyModeration, Variety & Nutrient Adequacy
Calories to Achieve/Maintain Healthy Weight
““The Steps”The Steps” For a Heart Healthy LifestyleFor a Heart Healthy Lifestyle
1.1. Eat lessEat less • Cholesterol• Saturated fat• Trans fat• Sodium
2.2. Eat moreEat more• Fiber• Soy-based products
““The Steps”The Steps” For a Heart Healthy LifestyleFor a Heart Healthy Lifestyle
3.3. Reduce your weightReduce your weight
4.4. Increase physical Increase physical activity levelactivity level
5.5. Learn toLearn to
• Shop smart• Cook smart• Dine out more
healthy
Step # 1Step # 1“Lowering Cholesterol & LDL Levels”“Lowering Cholesterol & LDL Levels”
• Eat less fat.Eat less fat.– Avoid fried foods, fatty meats,
& whole milk products.
• Eat less cholesterol.Eat less cholesterol. – Cholesterol is found in foods
from animals (foods from plants generally contain no cholesterol).
Step # 1Step # 1““Lowering Cholesterol & LDL levels”Lowering Cholesterol & LDL levels”
• Eat less saturated fat.Eat less saturated fat.– Saturated fats are usuallyusually
found in animal products.– However you should minimizeshould minimize
coconut, palm, and palm coconut, palm, and palm kernel oilkernel oil as they are high in saturated fat.
– Coconut oil – later
• Use lessUse less hydrogenated or hydrogenated or partially hydrogenated fats.partially hydrogenated fats.
Step # 1Step # 1““Lowering Trigylcerides”Lowering Trigylcerides”
• Avoid Alcohol.Avoid Alcohol.– Beer, wine, or hard liquor.
• Avoid Sugar.Avoid Sugar. – Candy & regular soda.
• Eat Fewer Carbohydrates.Eat Fewer Carbohydrates.– Breads, cereals, rice, pasta, fruits, &
dairy products.
What is Trans Fat?What is Trans Fat?• Also known as Trans fatty acids.Trans fatty acids.
• Type of fat formed when liquid oils are made into solid fats (process called hydrogenationhydrogenation).– Shortening– Hard margarine
• Trans fat can be found naturally,can be found naturally, in small amounts, in some animal-based foods.
• Trans fats are in packaged cookies, crackers, packaged cookies, crackers, other baked goods, commercially prepared other baked goods, commercially prepared fried foods, chips, doughnuts, some fried foods, chips, doughnuts, some margarines & most short-eatsmargarines & most short-eats
Why is it BadWhy is it Bad??
• Trans fat is as badis as bad for you as saturated fat.saturated fat.
• It has been shown to– raiseraise LDL levelsLDL levels – lowerlower HDL levels HDL levels– increaseincrease your risk for
heart disease
Step # 1Step # 1““Lowering Trans Fat”Lowering Trans Fat”
1. Choose liquid or soft margarines & use in moderation.
• 1 gm saturate fat/serving• First ingredient should read “liquid
vegetable oil”
2. Use olive or sunflower oil (natural, un-hydrogenated oils).
3. Look for processed foods that use un-hydrogenated oils.
4. Limit intake of foods high in trans-fat
Step # 1Step # 1““Decrease Sodium (Salt) Intake”Decrease Sodium (Salt) Intake”
• Eating a diet high in sodium (salt) can increaseincrease blood pressure.
– Canned foods, dried meats or fish, packaged foods, frozen meals, lunch meats, salad dressings, marinades, and any salted food item
• Having a normal blood pressure reduces the riskreduces the risk of heart disease.
Step # 2Step # 2““Increase Soluble Fiber Intake”Increase Soluble Fiber Intake”
• The type of fiber found in oats, barley, dry beans & oats, barley, dry beans & peas, fruits & vegetablespeas, fruits & vegetables may help to lowerlower cholesterol levels.
– Choose 5 or more servings of vegetables & fruits/day.
– Choose 6 or more servings of whole grain breads, cereals, pasta, rice, & dry beans/day.
Step # 2Step # 2““Increase Soy Intake”Increase Soy Intake”
• Soy protein has been shown to reducereduce the risk of heart disease.
• Add soy to your diet.– Tofu, soynuts, soymilk, or
other whole soy products.
– Don’t count on powdered soy drinks as a good source of soy protein.
Fish oils
CVD Therapy: omega-3-Fatty Acids
• Omega-3-EFAs 1000mg/day is also very effective
– Omega-3-EFA therapy significantly prevents:• cardiac arrhythmia• Thrombotic disorders
Coconut Oil???• Contain Saturated fats – But
medium chain fatty acids – lauric acid
• Medium chain FA – can be easily used by tissues
• Research done on hydorgenated coconut oils – not on pure oil.
• Recommendations– Generally take low– Better than hydrogenated oils or
other saturated oils– Better for deep frying than
unsaturated oils – like even sunflower oil
Benefits Vs Risks• Proven
– Wine reduces CVD– But Wine has flavinoids too!!
– One to Two drinks per day – reduces CVD, death
• Risks proven– Large mounts increases
– CVD, Obesity, Atherosclerosis– Chronic Liver diseases– Cancers
• Recommended• Men should drink no more than 21 units of alcohol per week
(and no more than four units in any one day).• Women should drink no more than 14 units of alcohol per
week (and no more than three units in any one day)• One unit of alcohol is 10 ml (1 cl) by volume, or 8 g by
weight, of pure alcohol. For example:
Recommendation
Combination therapy proven with research..
• Statin + omega-3FAs
• Statin & Niacin
Important Nutirents
• Arginine – Produces NO in vascular endothelial cells
• Vitamin C – Reduces development of CVD• Vitamin E – protects endothelium
• Selenium - works synergistically with Vit E
• Antioxidents – Flavanoids, • Vitamins B6, Folate, B12 & Betaine - reduce
serum homocysteine level • Garlic – Reduces progression of CVD
Evidence-based Best Practice Guideline,
New Zealand Guidelines Group, December 2003.1) Enjoy three meals a day, selecting from dishes that encourage you to eat
plant foods and fish, with little or no dairy fat, meat fat or deep fried foods2) Choose fruits and/or vegetables at every meal and most snacks.3) Select whole grains, whole grain breads, or high fibre breakfast cereals in
place of white bread and low fibre varieties at most meals and snacks4) Include fish, or dried peas, beans and soy products, or a small serving of
lean meat or skinned poultry, at one or two meals each day5) Choose low fat milk, low fat milk products, soy or legume products every
day 6) Use small amounts of oil, margarine, nuts or seeds7) Drink plenty of fluids each day, particularly water, and limit sugar-
sweetened drinks and alcohol8) Use only small amounts of total fats and oils, sugar and salt when
cooking and preparing meals, snacks, or drinks. Choose ready-prepared foods low in these ingredients
9) Mostly avoid or rarely include butter, deep-fried and fatty foods, and only occasionally choose sweet bakery products
Diet Therapy for High Blood Cholesterol
Diet Therapy for High Blood Cholesterol
(Data from National Cholesterol Education Program [NCEP]. Second Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults [Adult Treatment Panel II]. NIH Publication N. 93-3095. Bethesda, MD; National Institutes of Health. National Heart, Lung, and Blood Institute, 1993.) * Calories from alcohol not included.
Endothelial Dysfunction: Diet
Genes, Diet and Disease
Genomic research has identified multiple gene-regulated transcription binding proteins that are: a) responsive to dietary lipid and CHO intake and b) propel metabolism towards common disease phenotypes CHD, Hypertension, Insulin Resistance, Diabetes etc.
Individual gene variants have also been identified that affecta) disease development and b) response to nutritional and pharmacological therapy
• Normal Plasma K+ concentration 3.5 - 5mmol/L
• Major source of excretion-renal• Major intracellular cation• K+ in the ECF <2% of the total
body content• K+ intake-40-120
mmol/day,90% of which is absorbed by the GI tract.
Increased potassium release from cells• Pseudohyperkalemia• Metabolic acidosis• Insulin deficiency, hyperglycemia, and hyperosmolality• Increased tissue catabolism• β-adrenergic blockade• Digitalis overdose
Reduced urinary potassium excretion• Hypoaldosteronism• Renal failure• Effective circulating volume depletion• Hyperkalemic type 4 renal tubular acidosis
Hyperkalemia Causes
Hyperkalemia
• Identify condition that predisposes to hyperkalemia.
• Asymptomatic
• Generalised fatigue
• Paralysis
• Palpitations
• Severe Hyperkalemia-
Absence of P waves
Intraventricular blocks,BBB,
Progressive widening of QRS complex
Sine wave pattern ventricular fibrillation,asystole
Treatment
• Drug therapy
• Diet therapy– Can prevent as well
• Hemodialysis– When urgernt – end stage ECG changes,
Serum K is high
To avoid / limit