lipids

lipids

1. nonpolar compounds

2. simple

   • fats: fatty acids+glycerol
     • oils too but in a liquid state
     • ester
     • fatty acids are carboxylic acids
       • too can be like free acids in plasme
       • the chain can be saturated(simple binds) or unsaturated(one or more double binds)
         • unsaturated acids can be
           • monounsaturates polyunsaturates eicosanoids(20 carbons)
           • the majourity of natural fatty acids has cis-double binds
             • correct packaging in the cell membrane and alow the fatty acid interaction in compounds like phospholipids
           • some acids can be trans
             • health risk
       • the carboxylic carbon(number 1)
         • #2-A #3-B #4-Y
         • the last carbon is W
           • W9, W6, and W3
             • a double bind in the number counted since w
   • waxes: fatty acids+monohydric alcohol

3. complexes

   • fosfolipids
     • lipid+fosforic acid waste
       • the alcohol in general is glycerol
         • except in sphingophospholipids: sphingosine
       • examples
         • phosphatidylinositol cardiolipin
     • the main structural constituent of the cell membrane
   • glucolipids
     • fatty acid+sphingosine+carbohydrate
       • ceramide
       • an important action in nervous tissue and in the cell membrane
   • others
     • sulfolipids aminelipids lipoprotein
   • ester+group

4. precursors and derivates

   • fatty acids glycerol steroids fatty-aldehydes, ketonic bodies
   • liposoluble vitamines lipidic hormones

5. neuter

   • without charge
   • acylglycerols cholesterol cholesterol esters
     • triacylglycerols
       • the main storage of fatty acids in the body
       • fat tissue
     • cholesterol
       • steroid precursor
         • biliary acids sexual and adrenocotical hormones vitamine D

6. the lipids are transported in the body by LIPOPROTEINS

   • because are unsoluble in water
   • 4 main kinds of plasmatic lipids
     • triacylglycerol-16% phospholipids-30% cholesterol-14% cholesterol esters-36% free fatty acids-4%
       • FFA are metabolized quickly
         • FFA origin since triacylglycerol disintegration
         • in the blood associated with albumine
       • triacylglycerol saved in the fat tissue is broke by
         • HSL( hormone sensible lipase)
           • sensible to INSULIN
             • fat tissue is an insulin-dependent tissue
             • increase lypogenesis
         • in glycerol+fatty acid
   • 4 main groups of plasmatic lipoproteins
     • fat has a low density than the water
     • chylomicrons-derivates of intestinal absorption(triacylglycerol and other lipids)
       • lipids absorption
         • first for the lymphatic system
       • chylomicrons are catabolized quickly(1 hour), too the VLDL
         • fatty acids derivates of triacylglycerol(chylomicrons)
           • to the liver(20%), and (80%) fat cells, muscle, hearth
         • through lipoprotein lipase, the triacylglycerols in chylomicrons and VLDL are hydrolyzed
           • lipoprotein lipase is in the capillary walls
     • very low density(VLDL)-liver derivates to triacylglycerol exportation low density(LDL)-final step in the VLDL catabolism high density(HDL)-cholesterol transport, and chylomicrons and LDL metabolism
       • through hepatic lipase, HDL and chylomicrons remnants are metabolized
         • hepatic lipase is in the hepatic cells
         • liver catch lipoprotein remnants
       • through LDL receptors, LDL is metabolized in hepatic(70%) and extrahepatic tissues(30%)