Lipid Metabolism Revision Flashcards
(31 cards)
lipoprotein lipase site and co factors required
vascular endothelium of extra hepatic tissue
requires apo c 11 and phospholipids
lipoprotein lipase vs HSL vs pancreatic lipase
lipoprotein lipase- break TAG in blood (from chylomicron) for uptake during feeding
HSL- break TAG during fasting that is stored in adipose tissue for oxidation
pancreatic lipase- break TAG in cavity of intestine for digestion during feeding
glycerol fate
can’t be utilized by adipose tissue due to deficiency of glycerol kinase so goes to liver and kidney
key enzyme of lipolysis
HSL helped by MAG
how do long chain fatty acids get to mitochondria
they from acyl coA which does in inner space of mitochondrial matrix then binds with carnitine to make acyl carnitine with CPT1 and goes to matrix by carnitine shuttle and in the matrix of the mitochondria, CPT2 separates acyl coA from the carnitine and the carnitine goes back to inner space.
each cycle of FA oxidation will release
acetyl coA (enters krebbs after) formation of one FADH2 and one NADH
steps of beta oxidation
acyl coa – acyl CoA DH –> delta 2 trans enoyl coA –> beta hydroxyacyl coA –> b ketoacyl coA –> acetyl coA + new acyl coA (2 carbons less)
calculate # of acetyl coA
# of cycles
complete oxidation of FA
# of carbon / 2 # of acetyl coA - 1 7C-6
Importance of FA oxidation
- supply body with energy in starvation
2. formation of acetyl coA
malonyl coAA effect on b oxidation
produced during FA synthesis inhibits CPT 1
How is FADH2 released from peroxisomal oxidation regenerated?
by giving its H2 to H2O2 to from 2 H2O and it doesn’t go to ETC
refsum disease and symptoms
deficiency in a hydroxyls so accumulation of phytanic acid DBAP deafness blindness ataxia polyneuropathy
two systems for fatty acid synthesis
- cytosolic de novo (lipogenesis)
2. microsomal system for elongation
acetyl coA for FA synthesis comes from
carbohydrate metabolism
site of cytosolic or de novo fatty acid synthesis vs microsomal
de novo: liver and lactating mammary gland and some in adipose tissue
microsomal: endoplasmic reticulum
how is acetyl coA produced from TCA go to cytosol for de novo synthesis and what happens to oxaloacetate
through citrate shuttle
oxaloacetate is then turned to malate then to pyruvate by Malik enzyme which can go back to mitochondria .
you can convert oxaloacetate straight to pyruvate if you don’t need NADPH+H
FA synthesis enzymes
ACC- acetyl coA -> malonyl CoA
FAS- multi enzyme complex (7 enzymes and have acetyl carrier protein)
product of FA synthesis
palmitic acid
microsomal system differs from denote in 3 aspects
- can’t imitate, just elongate from 10-24
- enzymes are separate
- no ACP
glycerol 3 phosphate in adipose tissue
no glycerokinase in adipose tissue (only liver and kidney) so produced by glucose by turning it into DHAB.
tissue fat vs depot fat site function composition amount and effect on diet
tissue- every cell, enter in structural elements and not used for energy. made up of phospholipids, glycolipids and cholesterol. constant and not affected by diet.
depot fat- adipose tissue and for energy storage, TAG and increases by overeating and decreases by fasting
tissue fat or depot fat?
which is rich in saturated and unsaturated fatty acids?
tissue fat- unsaturated fatty acids
depot fat- saturated fatty acids
how are cyclic compounds formed?
from prostaglandin H synthase which has 2 activates: COX and peroxidase
COX 1 vs COX 2
cox 1 - enzyme found in most tissues
cox 2- enzyme that is generated due to response to inflammation
