1Why lipids cannot be transported in blood alone? 2How we transport Fatty acids and steroid hormones? 3How are dietary lipids transported? 4How lipids synthesized in the liver are transported? 5 Lipoprotien molecules contain? 6 VLDL is secrete by? 7 Delivers triglycerides from liver to? 8 Cellular uptake of LDL requires LDL receptors. LDL receptors recognize the apo protein. 9 In the presence of an accumulation of these cells, a linear will become visible on the inside of the artery, bulging into the lumen. 10 The macrophages uptake only oxidized lipids through the receptor. Lipids are oxidized by. Therefore may help protect from the development of atherosclerosis. Hybrphocitiy 2 albumin 3-chylomicrons 4 lipoproteins 5-1) contain phospholipids, cholesterol, and apoproteins 2) triacylglycerols and cholesterol esters in the inside 6Liver 7tissues 8apoB-100 (bind LDL receptor). 9 fatty streak 10 SR-A1 free radicals antioxidants 75
11. In atherosclerosis the cells at the centre of the plaque are a. Macrophages b. Foam cells c. Leukocytes d. Smooth muscle cells e.? 12. All of the following are major risk factors for atherosclerosis EXCEPT: a Obesity b. Hyperlipidaemia c. Smoking d. Hypertension e. Diabetes 15 Which of the following statements about circulating lipoproteins is correct? 13 Atherosclerosis a. Is initiated by endothelial injury b. Is a disease of the media of blood vessels c. Predominantly involves arterioles d. Is most common in the internal carotid arteries e. Begins in middle age 14. Regarding atherosclerosis a. The risk is directly related to HDL (high density lipoprotein) levels B It typically beings in childhood, but only manifests itself in later life c. It involves smaller elastic and larger muscular arteries d. 20% of all deaths in USA are attributable to this disease process a) Chylomicrons release cholesterol to adipose tissues. b) VLDL release cholesterol to the liver. c) chylomicrons contain mainly dietary triacylglycerols in their core. d) LDL contain mainly dietary triacylglycerols in their core.
L 8 Abnormalities of lipid metabolism Clinical chemistry 10-12-2017
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Small oxidized LDL Plaque formation
Oxidized LDL and atherosclerosis 3
Plaques consist of : -cholesterol, -oxidized lipids, -inflammatory cells such as neutrophils and macrophages, which accumulate under the endothelial lining of the artery and extend into the arterial wall.
atherogenic lipid profile: LDL (esp. small, dense, oxidised) apob (= reflect better LDL particle number than conc. of LDL) HDL apo(a) TAG (if accompanied by FFA) ƒtag contribute to the formation of small dense LDL
small dense LDL particles damage arteries because: 1- the particles stay longer in the blood and are damaged by oxidation 2-the altered and smaller particles are taken up by scavenger receptors in the lining of blood vessels and form atheromas. Atheroma Jfi
Classification of lipid disorders A-Fredrickson classification JFI -genetic rare disorders -according to Fredrickson classification, the disorders are mainly 6 types, Familial combined hyperlipidaemia is most common type caused by an overproduction of VLDL, which is the precursor of LDL, resulting in rise of TG AND CHOLESTROL levels. Xanthoma fat deposits full of lipids 5
Classification of lipid disorders B-Secondary lipid disorders *Are those arising as a consequence of a disease( hypothyroidism),drug treatment, defective nutrition Mixed dyslipidemia : mainly caused by excessive intake of FFA from food ( fat, carbohydrates). The FFA are delivered to the liver, causing increased production of VLDL. Obesity : results from dysfunctional fat metabolism or increased fat intke, FFA are delivered to the liver, causing increased production of VLDL. Alcohol consumption promotes overproduction of FA s, increasing VLDL. A major mechanism for overproduction of VLDL is insulin resistance, because insulin normally suppress the release of FA from adipose stores. resistance of the adipocytes to insulin causes excessive release of FAs with hepatic overproduction of VLDL. Drugs used to treat AIDS damage fat cells causing insulin resistance 6
Q) serum sample from a patient had a milky appearance and produced very high TG content. A-What lipoprotein is causing this? B-And what is the clinical significance of this test result? A-VLDL particles and chylomicrons. (b) When TAG concentrations are more than 10 mmol/l, chylomicrons are present. high chylomicrons (Very high TAGs) can cause inflammation of the pancreas. The best treatment is a low fat diet but drugs may also be necessary. Lipemic serum 7