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
Common things in B9 and B12 defeciency with reasons
1) Megaloblastic anemia (because both vitamins help in purine synthesis)
2) High level of homocysteine in serum and urine(because methionine is formed from homocysteine with the help of both vitamins)
3) Multiple lobed nucleus of neutrophils
4) Glossitis
Folate deficiency
Cobalamin defeciency
Folate deficiency is common in pregnant women,neural tube defects,nA very little of it is stored in liver(**),common in alcoholics,macrocytic anemia…
Cobalamin def causes pernicious anemia,paresthesia(tingling and numbness of finger n toes),high levels of methyl malonic acid in blood and serum
Vitamin k
Phylloquinone, …synthesised by gut flora,helps in gamma carboxyltion of [clotting factor (7,10,9,2)and protein(c and s) and glutamic acid to gamma carboxy glutamate]….heparin ,warfarin and bishydroxycumarin are anticoagulants
Calcium function ,hypocalcemia causes___ and hypercalcemia ___
Component of hydroxyapatite, signalling ,impulse transmission,muscle contraction,blood clotting.hypocalcemia with PTH or vit D def causes kidney stones…hypercalcemia with î PTH causes bone resorption
Chloride, magnesium ,hypomagnesemia and hyper magnesemia
Chloride —>fluid balance and digestion.
Magnesium—>minor component of bone,regulate enzyme activity….hyper excitability,muscular irritation,weakness and convulsions seen with hypo magnesemia
