1. Midterm is 2 March in class Lectures 1a-6b inclusive-50 multiple choice-50 points One short answer question-10 points Lecture 5b 3 February 2016 Most of this lecture taken from Chapters 5,7 of Rolfes et al(Understanding Normal and Clinical Nutrition(Nutrition 2104/2106 text)

2. Outline of lectures 5a,b Lipids classified -fatty acids -saturation -triglycerides -phospholipids -sterols

3. Outline of lectures 5a,b Lipids -digestion -absorption -transport

4. Outline of lectures 5a,b Lipids in the body -roles of triglycerides -essential fatty acids

5. Outline of lectures 5a,b Preview of lipid metabolism

6. Outline of lectures 5a,b Lipid Metabolism -fatty acid catabolism -fatty acid anabolism -triglyceride catabolism -triglyceride anabolism -cholesterol catabolism -cholesterol anabolism -phospholipid catabolism -phospholipid anabolism -regulation

7. More detailed comments

8. Lipids classified -phospholipids example-choline containing phospholipids 2 fatty acids and a choline head group attached to glycerol -diagram

10. Lipids classified -phospholipids -ethanolamine containing phospholipids -2 fatty acids and an ethanolamine head group attached to glycerol -phosphatidylinositol -2 fatty acids and an inositol head group attached to glycerol

11. Lipids classified -phospholipids -phosphatidylserine -2 fatty acids and a serine head group attached to glycerol -sphingomyelin -one fatty acid and 2 other groups attached to glycerol

12. Lipids classified -sterols -cholesterol -various hormones (eg estrogen, testosterone) made from cholesterol

13. Diag chol

14. Lipids -digestion -mouth -lingual lipase -adults-minor role -infants- major role in digesting short and medium chain fatty acids

15. Lipids -digestion -stomach-no digestion -small intestine- pancreatic lipase-digests fatty acids from triglycerides -role of bile (figure 5-14, Rolfes)

17. Lipids -absorption -glycerol, short and medium chain fatty acids go directly into blood -monoglycerides and long chain fatty acids are formed into micelles which are moved into intestinal cells in intestinal cells ultimately get phospholipids and triglycerides formed into chylomicrons which are moved into lymph - from lymph go into blood

18. Lipids -transport lipoproteins -fat protein particles-protein required to give water solubility to lipids -chylomicrons -very low density lipoprotein -low density lipoprotein -lipoprotein (a) -high density lipoprotein -albumin -lipoprotein density affected by ratio of lipid to protein in a lipoprotein

19. Lipids in the body -roles of triglycerides -primarily energy -fat stores -participates in carbohydrate metabolism -protein sparing

20. Lipids in the body -essential fatty acids -linoleic -alpha-linolenic

21. Preview of lipid metabolism -fat is made into fat -carbohydrate and protein can make fat

22. Lipid Metabolism -fatty acid catabolism -fatty acids made into acetyl CoA -acetyl CoA follows TCA cycle -ATP is made

23. Lipid Metabolism -fatty acid anabolism -acetyl CoA can be made into fatty acids -omega 6 and omega 3 pathways -ATP is used

24. Lipid Metabolism -triglyceride catabolism -to glycerol and fatty acids -triglyceride anabolism -fatty acids and glycerol make triglycerides

25. Lipid Metabolism -cholesterol catabolism -largely made into bile -cholesterol anabolism -acetyl CoA made into cholesterol

26. Lipid Metabolism -phospholipid catabolism -made into glycerol, fatty acids and head group (eg choline) -phospholipid anabolism -made from glycerol, fatty acids and head group (eg choline)

27. Lipid Metabolism -regulation-closely linked to carbohydrate availability -lots of carbohydrate-favours fatty acid synthesis-due to lots of malonyl CoA which inhibits carnitine acyl transferase I that allows for transfer of fatty acids to carnitine for transport into mitochondria for oxidation to acetyl CoA- also if not enough carbohydrate for fatty acid synthesis but not so little that there is sufficient OAA-fatty acids are metabolised through the Krebs cycle (acetyl CoA from fatty acids joins with OAA to make citrate) -little carbohydrate-favours fatty acid catabolism to ketones (acetyl CoA is converted to ketone as OAA is converted to glucose)