P1 BIOCHEM HEME SYNTHESIS Flashcards
incase of decreased iron levels Pt will develop
anemia
incase of increased iron levels Pt will develop
iron overload diseases
blood picture in iron Def. anemia
hypochromic microcytic
causes of iron def. anemia
- nutritional
- increased demand
- inflammation
- reduced absorption
normal serum ferritin range
50-200
iron overload without tissue damage
hemosiderosis
iron overload with tissue damage
Hemochromatosis
hemochromatosis is due to
Ingested iron is not eliminated
mention a condition that is associated with iron overload
Alcoholic liver disease
more soluble form of iron
Ferrous / Fever 2+
iron form less soluble at neutral / alkaline PH
ferric / Fe3+
ferric form is less soluble due to
they form large complex anions / peroxides
type of iron in meat , fish . Poultry
Heme iron
type of of iron found in meat , fish , cereals , pulses
nonheme iron
site of absorption of iron
Proximal duodenum & upper jejunum
molecule that absorbs heme iron in proximal intestines
HT/HCP1
reduction from ferric form to ferrous form is done by
Duodenal cytochrome B
transporter protein of iron through the intestinal lumen
divalent metal transporter1 / DMT1
major storage site for iron
liver
major utilization site of iron
bone marrow
MOA of hepcidin
Antagonising action of ferroportin
site of heme synthesis
Erythroid cells of bone Marrow
hepatocytes
site of synthesis of delta aminolevulinic acid
Mitochondria
enzyme responsible for rate limiting step in heme synthesis
d-Aminolevulinate Synthase
site of formation of porphobilinogen
cytoplasm
formation of porphobilinogen is done by
porphobilinogen synthase /ALA Dehydrase
element that can cause toxicity binding to ALA dehydrase
lead
Process that is catalyzed by PBG deaminase
Formation of hydroxymethylbilane
Protoporphyrinogen IX is converted in to protoporphyrin IX by
protoporphyrinogen IX oxidase.
final reaction of heme synthesis is catalyzed by
ferrochelatase
(heme synthase)
RBCs are degraded by
Mononuclear phagocyte system/ reticuloendothelial system
site of RBCs degradation
liver & spleen
RBCs are degraded into
heme & globin
heme conversion into biliverdin is done by
heme oxygenase
biliverdin is converted to bilirubin is done by
biliverdin reductase
disorder of heme synthesis
Porphyria
Porphyria that results from lead / heavy metals / drugs
Acquired porphyria
enzymes inhibited in acquired porphyria
- ferrochelatase
- aminolevulinate dehydrase
- uroporphyrinogen synthase