Vitamin B1 Flashcards
(33 cards)
Vitamin B1
Thiamin
Christian Eijkman
Dutch Physician in Indonesia, starts studying an endemic disease called beriberi
Gerrit Grijns
Makes association between beriberi and excessive consumption of polished rice.
Casimir Funk
Isolates a vital substance called anti-beriberi factor; COINS TERM vitamin (vital amine)
Robert Williams
synthesizes the vitamin and names it thiamin (sulfur-containing vitamine)
Food sources
Brown rice, pork, cured ham
Apical membrane
Thiamine transporter-2
Basal lateral membrane
Thiamine transporter-1
Required for uptake
THTR 2
Circulating form
Thiamine diphosphate (TDP)
What is added in the liver?
2 phosphate groups
90% of thiamin in blood is?
in the erythrocytes
Thiamin is bound to…
albumin
What is thiamin taken up by in peripheral tissues?
THTR-1
What is thiamin taken up by in skeletal muscle, heart, brain, liver and kidney?
THTR-2
Body Storage
25-30 mg
Thiamine Excretion
Urine– mainly as free thiamin and TMP
Thiamin function
coenzyme in oxidative decarboxylations & transketolase
Oxidative decarboxylations
Pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, & Branch-chain alpha keto acid dehydrogenase
Transketolase
Enzyme in RBC.
Activity of transketolase
Depends on RBC
Testing for deficiency
Transketolase
Thiamin Deficiency
Relatively Rare. Alcoholics.
Symptoms of deficiency
Difficulty walking,loss of feeling in hands and feet, confusion & altered heart rate.