PPT-Lipoproteins and cholesterol

CVS 20182 ND SEMESTER Four major groups of lipoproteins are recognized Chylomicrons transport lipids resulting from digestion Lipid Metabolism and absorptionDerived from intestinal absorption of TG . Learning outcome. Most cholesterol is synthesised by the liver from saturated fats in the diet. Cholesterol is a component of cell membranes and a precursor for steroid synthesis. High-density lipoprotein (HDL) transports excess cholesterol from the body cells to the liver for elimination. This prevents accumulation of cholesterol in the blood. Low-density lipoprotein (LDL) transports cholesterol to body cells. Most cells have LDL receptors that take LDL into the cell where it releases cholesterol. Once a cell has sufficient cholesterol a negative feedback system inhibits the synthesis of new LDL receptors and LDL circulates in the blood where it may deposit cholesterol in the arteries forming atheromas. A higher ratio of HDL to LDL will result in lower blood cholesterol and a reduced chance of atherosclerosis. . FromEgg. Yolk. Cholesterol. Is the most abundant . steroid. in the body.. Is a . waxy. substance found in all of the body cells. . Has . methyl. CH. 3. - groups, alkyl chain, and -OH attached to the steroid nucleus.. 5/e. Karen C. Timberlake. © 2016 Pearson Education, Inc.. 17.6 Steroids: Cholesterol, Bile Salts, and Steroid Hormones. High- and low-density lipoproteins transport cholesterol between the tissues and the liver.. Cholesterol. Is the most abundant . steroid. in the body.. Is a . waxy. substance found in all of the body cells. . Has . methyl. CH. 3. - groups, alkyl chain, and -OH attached to the steroid nucleus.. Lipoproteins. are . types of . Compound Lipids /. Conjugated . Proteins. .. Lipoproteins . are . macromolecules. formed by aggregation of. . :. Lipids . (Neutral . and A. mphipathic ). Proteins. ( Apoprotein) in the human body.. Ray . Hreiche. (updated slides from . Mohana. . Ratnapalan. & Anna . Sher. ). (THANK YOU!!!). Learning Objectives . Explain the physiological functions of cholesterol in membrane stability.. Outline the synthesis of cholesterol from acetate.. Plasma lipids . 200 . Lipoproteins . 201 . Fatty acids . 200 . Disorders of lipid metabolism . 207 . Cholesterol . 201 . Investigation of hyperlipidaemias . 214 . FATTY ACIDS . Lipids play a critical role in almost all aspects of . Learning. . Objectives. The structure and composition of lipoproteins. Exogenous dietary fat transport vs. endogenous fat transport systems. Key enzymes involved in lipoprotein metabolism. Key cholesterol transporting lipoproteins and the relationship between their concentrations and the incidence of cardiovascular diseases. .. Importance of lipoproteins formation. .        . 1- . Lipids are water insoluble substance and can not be trasported in an aqueous medium (blood plasma )..             . 2- in order to transport lipids between blood and different tissues they are associated with a protein to form water soluble complex . Dr.Deepa.G.S. Associate Professor. Dept.of. Physiology. Lipoproteins. Molecular complexes that consists of lipids and proteins. They function as transport vehicles for lipids in plasma. Lipoproteins-Structure. Cardiovascular . Block. Dr. . Usman. . Ghani. Objectives. By the end of this lecture, the First Year students will be able to:. Correlate . the imbalance . in lipoprotein metabolism with the development of . D.Pharm. , . Bpharm. , MSc ). O. utl. i. ne. Introduction. Definition of terminologies. Lipoprotein disorders. Types of dyslipidemia. Approaches to Management . Role. . and. . responsibili. ty of. . They bind with . soluble . protein. complexes . called. . lipoproteins. Lipids . can . be derived from food (exogenous) or synthesized. in the body (endogenous). The water-soluble (polar). groups of proteins, phospholipids and free cholesterol. Main lipids in the blood are the triglycerides and cholesterol.. Insoluble in the water.. Transport in the blood is via lipoproteins. Triglycerides. Glycerol with 3 attached fatty acids. Exogenous source : Dietary.