Vitamins Flashcards
Vitamin B1
Function
THIGHmine (beegun)(pyrimidine+thiazole)
Combine with 2 phosphates to form thiamine pyrophosphate(TPP) which works with many enzymes like1-pyruvate dehydrogenase(pyruvate—>acetyl COA) 2-alpha ketoglutarate dehydrogenase (in TCA cycle) 3-branched chain alpha keto acid dehydrogenase( convert branch chain amino acids—> repective keto acids) and B1 also help in acetylcholine formation
B1 deficiency and dietrt sourcws
Outer layer of cereals and pulses seeds etc
Wernike-korsakoff syndrome mostly in alcoholics bcz it’s mostly used there
Symptoms include ataxia ,confusion, nystagmus (a to-and-fro motion of the eyeballs), and ophthalmoplegia (weakness of eye muscles)
2) symptoms appear when glucose is taken before thiamin
3) dry beriberi - neuritis
4) wet beriberi- heart becomes weak pulse î and edema in face legs etc
Vit B2
Function
Deficiency
Ribo-flavin(beeshoe) composed of isoalloxazine +ribitol
It form co-enzymes FAD and FMN(flavin mononucleotide)
Isoalloxazine part accept 2 H
F:Acts as a co-factor for succinate dehydrogenase and many other RED-OX reactions
D: cheilosis(fissure at the ends of mouth) and lips inflammation and corneal vascularisation
Vit b3 composition and from what it can be made
Niacin or nicotinic acid ; composed of pyridine 3 carboxylic acid. Its amide form is niacinamide. It can be made from tryptophan amino acid, Pyridoxine and riboflavin. It make NAD and NADP
Function of niacin
1: make NAD and NADP (help in redox reactions)
2: decrease lipolysis of lipid hence decrease VLDL(synthesised from TAG) and LDL ( contain cholestrol)conc. Bcz fatty acids are not made from lipolysis. Therefore niacin cam be used in trtmnt of hyperlipoproteinemia( elevated ldl amd vldl)
3: î HDL
Niacin deficiency and dietry source
Yeast , liver and cereals
Def causes pellagra which causes 3 Ds dementia , dermatitis( associated with degeneration of nervous s symptoms include poor memory , insomnia and anxiety) and diarrhoea .pellagra is observed in hartnups disease and carcinoid syndrome.
Pentothenic acid
B5 . Made of pentoic acid and beta alanin
Makes CoA . And helps in fatty acid synthesis
Def may cause dermatitis,alopecia(bald spot),adrenal insufficiency and enteritis
Vit C its functions
It is a strong__
It’s a strong reducing agent
L-ascorbic acid—> De-hydro L ascorbic acid+ 2H
It can undergo reversible oxidation-red reaction
1) strong anti-oxidant-> prevents vit A,E and some B from oxidation
2) converts ferric+3–>ferrous+2
3) works as co-enzyme in collagen synthesis by hydroxylation of proline and lysine
4) helps dopamine beta-hydroxylase in converting dopamine—> catecholamines(nor-epi..&E)
5) helps converting methemoglobin into hb
Vitamin D
How it is formed
Calciferol derivates
D2- ergocalciferol found in plants
D3- cholecalciferol
Stored in inactive form in liver. Here 25- hydroxylase converts it into cholecalciferol which is further converted into 1,25 di hydroxy cholecalciferol by alpha 1-hydroxylase in kidneys.
It controls ca and phosphate levels
7-dehydrocalciferol(intermediate of chlestrol metabolism) stored in liver—>cholecalciferol(with help of sunlight)——> 1,25DHCC(calcitriol)
Hyper level causes bone resorption
Vitamin D functions and what controls it’s level
Vitamin D functions on 3 major sites
i) intestine-as it is fat soluble therefore passes cm and binds cytosol proteins —> instruct DNA to form calbindin —> attaches to cm and binds ca
ii) in bones it helps ca absorption
iii) in kidneys it work to prevent excretion of ca
When phosphate level ! Alpha one hydroxylase works and convert calcidiol into calcitriol
When ca level drops parathormone level Î and again this enzyme works better
Vitamin E function and def
Vitamin eel Aka tocopherol
Function:1) works as an antioxidant- essential for membrane integrity n prevents hemolysis n prevent oxidation of vit A + carotenes
2) enhance affect of warfarin
Def: .muscle weakness
.Dorsal columns(demyelination in dorsal column
And spinocerebellar tract
. Hemolysis( hemolytic anemia)
B9 and functions
Folate or folic acid
Active form is tetra-hydrofolate(THF)
Function:helps in 1 carbon metabolism
i-e 1) purine synthesis
2)pryimidine synethesis
3) Glycine , serine , ethanolamine synthesis
4) N-formyl methione(initiator of translation) synthesis
B12 and function
Cobalamin
Parietalb cells release hcl and intrinsic factor which binds cobalamin and they are absorde in terminal ileum..
Function:—1) methionine synthesis from homocysteine
2) methyl malonyl Co-A(formed by breakdown of fatty acids,some amino acids and pyrimidone)——(methyl malonyl Co-A mutase enzyme + b12)———-> succinyl Co-A
Vit A is used for treatment of
1) measles
2) dry skin
3) psoriasis
Vit A
Hay- retinol Anti-oxidant Fat soluble vitamin Visual pigments formation Cellular differentiation Treats acne,measles ATR(all trans retinoic acid ) formation—> prevent APL (acute promyelocytic anemia) Prevent keratin synthesis therefore maintain normal epithelial structure
