Vitamins Flashcards
Organic compound required in the diet In small amounts for maintenance of normal metabolic integrity
Vitamins
Not considered as vitamins
Vit D and Niacin
Two types of vitamins
Water and Fat soluble
Types of water soluble vitamins
B and Non B Complex
Example of Non B complex
Vit C
Types of B complex Vitamins
Energy-releasing: Thiamine (B1), Riboflavin (B2), Niacin (B3), Biotin, Pantothenic Acid
Hematopoeitic: Folic Acid, Vit B12
Others: Pyridoxine, Pyridoxal, Pyridoxamine
Fat-soluble vitamins
ADEK
Vitamin for vision and cell differentiation
Vit A
Vitamin for Calcium and Phosphate metabolism and cell Differentiation
Vit D
A fat soluble vitamin that is an oxidant
Vit E
Vitamin essential for blood clot
Vit K
A person with definciency in Vit A is prone to
Night blindedness and Xeropthalmia
A person with rickets (young) or osteomalacia (adult) has deficiency in what vitamin?
Vit D
Vit E deficiency
Neurologic disorders and Hemolytic Anemia
HDN is a deficiency in
Vit K
Absorption of fat-soluble vitamins is dependent on
Ileum, bile, pancreas
Toxicity is more common and affected by malabsorption syndromes
Fat-Soluble Vitamins
What are the Malabsorption Syndromes?
Cystic Fibrosis
Celiac Sprue
Mineral Oil Intake
Forms of Vitamin A
Retinol
Retinal
Retinoic acid
Storage form of Vit A
Retinyl Esters
Vitamin A is also known as
Beta carotene
Transport form of Vit A
RBP retinol binding protein
Vitamin A is mainly stored where? And in what specific cells?
Liver, Ito cells
Transported with chylomicrons
Vit A for regeneration of epithelium (skin and cancer)
Retinoic Acid
Two types of Retinoic Acid
Tretinoin: all-trans (for psoriasis)
Isotretinoin: 13-cis (for severe acne)
Vit A that supports gametogenesis in gonads
Retinol
Vit A that is highly teratogenic
Isotretinoin
Only vit used in trx of cancers
Tretinoin
Vit A present in rods and cone cells for vision
Function as prosthetic group of opsins
Retinal
Vit A def: lost of sensitivity to green light will lead to
Nyctalopia (night blindedness)
Vit A def that leads to corneal keratinization and ulceration
Xeropthalmia
Corneal keratinization that occurs in conjunctiva
Vitot’s spots
Vitamin a excess (hypervitaminosis A)
Pseudotumor cerebru Excessive dryness, desquamation, alopecia Hepatomegaly Inc fractures Teratogenic
Pseudotumor cerebri (inc ICP) can be seen in patients with
Excess vit A
Other term for Vit D
Calciferol
Types of Vit D
Ergocalciferol
Cholecalciferol
Calcitrol
Vit D2, milk, plant sources
Ergo calciferol
Vit D3, skin, animal sources
Cholecalciferol
Precursor of Vit D
7 dehydrocholesterol
Storage form of Vit D
25-(OH) vit D3
Active form of vit D
1,25-(OH)2 vit D3 (calcitriol)
Considered as the most toxic vitamin, why?
Vit D
Affects the heart and kidney
Vit D comes from
Cholesterol
Vit D synthesis
Starts: skin
1st activation: Liver
2nd activation: Kidney
Vitamin that responds to hypocalcemia and PTH
Vit D
End goal: inc calcium, inc PO4
Inc intestinal abs of calcium
Inc bone resorption
Inc kidney reabsorption
What is the effect of Vit D in the bones at artery level
Bone deposition
Effect of Vit D in increased toxic dose
Bone resorption –calcium goes to bld:hypercalcemia
Vit D deficiency in children
Rickets (before growth palate closes)
Vit D deficiency in adult (after growth palate closes)
Osteomalacia
What causes Rickets/Osteomalacia?
Lack of vit D, calcium in diet
Lack of sunlight exposure
Intestinal malabsorption
Chronic Renal FailurTarget Organ resistance
Vitamin D excess (hypervitaminosis D)
Hypercalcemia
Anorexia and nausea
Thirst
Stupor
Other term for Vitamin E
Alpha tocopherol
Functions as an antioxidant in the lipid phase
Vitamin E
Protects membrane lipids from peroxidation
Vit E
Prevents oxidation of LDL therefore improving blood flow (dec atherogenesis)
Vit E
Condition in which dietary deficiency among humans is actually unknown
Vitamin E deficiency
Vitamin excess (least toxic vitamin)
Vitamin E
Vitamin E deficiency
Rbc fragility leading to HA
Neurologic dysfxn (neuropathy)
Muscle Membrane Damage
Types of vit K
Phylloquinone: K1: green veggies
Menaquinome: K2: intestinal bact
Menadione: synthetic
Type of vitamin k found in green vegetablea
Vit K1 - Phylloquinone
Vitamin K found in Intestinal Bacteria
Vit K2: menaquinone
Synthetic type of Vitamin K
Menadione
Vitamin K1 is also known as
Phylloquinone
Menaquinone is also known as
Vitamin K2
Functions for the carboxylation of glutamic acid residues in many calcium-binding proteins
Vitamin K
Vitamin k dependent calcium binding proteins
Coag factors (2,7,9,10) Protein C and S
Deficiency of this vitamin is rare because it can be produced by bacterianin the GIT
Vitamin k deficiency
In HDN, presents as bleeding (including intracranial bleeds)
Vitamin K deficiency
Neonates are at risk because of sterile GIT and low content in breastmilk
Vit K deficiency
Vit K excess presents as
Jaundice + hemolytic anemia
Antidote for Heparin
Protamine Sulfate
Heparin is given
Intravenously
Warfarin and coumadin is given
Orally
Vit K and FFP is the antidote for
Warfarin
Inhibits vit k dependent coagulation factors
Warfarin
Vit B1
Thiamine
Riboflavin
Vit B2
Vitamin B3
Niacin
Pantothenic Acid
B5
Vit B6
Pyridoxine (Pyridoxal phosphate)
Cobalamin
Vit B12
Vit B1 deficiency
Beri beri
Riboflavin def
Chellosis
Glossitis
Seborrhea
Vitamin B3 def
Pellagra
Cobalamin deficiency
Megaloblastic anemia
Methylmalonic aciduria
Pernicious anemia
Scurvy is a deficiency in
Vitamin C
Folate deficiency
Megaloblastic anemia
Excess water soluble vitamins wash out of the body in urine except
Vitamin B3, B6, B12
Active form of Vit B1
Thiamine pyrophosphate (TPP)
Used as cofactor in pyruvate dehydrogenase, alpha ketoglutarate dehydrogenase and branched chain AA dehydrogenase
Thiamine
Transketolase rxns in the HMP shunt
Thiamine
Vit B1 def
Beri beri
Wernicke-korsakoff syndrome
Types of beri beri
Dry = no heart failure, symmetrical muscle wasting
Wet = with heart failure, high output cardiac failure, edema
Manifestations of wernicke encephalopathy
ACO
Ataxia
Confusion
Opthalmoplegia
Manifestations of Korsakoff Psychosis
CHA
Confabulation
Hallucination
Amnesia
FAD and FMN is the active form of
Riboflavin
FAD
Flavin adenine dinucleotide
FMN
Flavin mononucleotide
Used as cofactors in redox rxns and electron carrier
Riboflavin, Niacin
Has intense yellow color: used as food preservative
Riboflavin
Primary source of riboflavin
Milk
Vit B2 deficiency
No def state, but with s/sx: Stomatitis Chellosis Seborrheic dermatitis Corneal vascularization
Active form of niacin
NAD and NADP
Source of ADP- Ribose: for proteins and nucleoproteins in DNA repair
Niacin
May be derived from Tryptophan using vitamin B6
Niacin
Niacin may be derived from tryptophan using what?
Vit B6
To what AA can you derive Niacin bg using Vit B6
Tryptophan
Niacin def presents as
Pellagra
Pellagra is?
4Ds: diarrhea
Dermatitis
Dementia
Death
Hartnup disease
Dec tryptophan absorption
Inc tryptophan metabolism will result to
Carcinoid syndrome
What is the effect of Isoniazid to Vit B6
Decrease
Can be given to TB Patients together with Vit B supplements
Isoniazid
Excess in niacin manifests as
Liver damage
A constituent of Coenzyme A
Pantothenic Acid ( Vit B5)
Used as cofactors for acyl transfers
Vit B5
Component if fatty acid synthase
Vit B5
Deficiency of this vitamin usually happens in animals
Vit B5
With s/sx: Dermatitis Enteritis Alipecia Adrenal insufficiency
What is the active form of pyridoxine?
Pyridoxal phosphate
Used as coenzyme in AA transamination, glycogen phosphorylase, cystathionine synthase, ALA synthase
Pyridoxine
Removes hornone-receptor complex from DNA: stops steroid hormone action
Pyrodoxine
Pyridoxine is also known as
Vitamin B6
Deficiency will lead to isoniazid toxicity and peripheral neuropathy
Pyridoxine
Intake of >299 mg/day will lead to gait problems and CNS Toxicity (excess)
Pyridoxine
Vitamin that has cobalt in center of corrin ring
Cobalamin (B12)
Types of vit B12
Methylcobalamin and cyanocobalamin
Cobalamin binds initially to ________ in the stomach
Salivary cobalophilin
Vitamin that needs intrinsic factor for absorption and is absorbed in terminal ileum
Cobalamin
Cobalamin is absorbed in what part of the stomach
Terminal ileum
2 active forma of cobalamine
5 deoxyadenosylcobalamin and
Methylcobalamin
Active form of cobalamin used for methionine synthesis
5deoxyadenosylcobalamin
Active form of cobalamin used for isomerization reactions
Methylcobalamin
Deficiency in this vitamin will lead to Pernicious Anemia/ Megaloblastic Anemia due to auto immunity
Cobalamin
Deficiency of this vitamin will lead to autoimmune destruction of parietal cells leading to decreased IF secretion and decreased vit B12 absorption
Vitamin B12
Diagnostic test for Vit B12 deficiency
Schilling test, vit B12, anti-IF
Malabsorption or absence of terminal ileum will result to
Vitamin b12 deficiency
Structure: pterin ring + PABA + glutamate residues
Folic Acid
Humans cannot synthesize folate because it cannot synthesize what substances?
PABA and add glutamate
This vitamin should be provided by the diet
Folic Acid
Active form of Folic Acid
Tetrahydrofolate (THF)
PABA to DHF to THF
Used as coenzyme for 1 carbon transfer (methylation reactions)
Folic Acid
Anti cancer drugs that inhibits dihydrofolate reductase of humans
Methotrexate
An antimetabolite antibiotic that inhibits both processes in THF synthesis of bacteria
Co trimoxazole
Inhibits dihydrofolate reductase
Trimethoprim
Sulfamethoxazole inhibits what?
Dihydropteroate synthase
Most common vitamin deficiency in developed countries
Folic Acid def
Deficiency in this vitamin will lead to megaloblastic anemia with no neurologic symptoms
- hypersegmentation of neutrophils
- macrocytic anemia
Folic Acid
When is the best time to five Folic Acid to pregnant mothers
Before conception upto first trimester
What is the dosage of folic acid given to pregnant women
400 mcg daily
Why is Folic Acid is given to pregnant women
To prevent neural tube defects
Functional folate deficiency is seen in cases with
Inc homocystiene leading to inc risk of MI
Used as cofactor for carboxylation reactions
Biotin
Biotin deficiency can be induced by
Avidin in egg whites
–prevents biotin absorption
Used as cofactor in hydroxylation of proline and lysine (collagen synth) and dopamine beta hydroxylase
(Dopa to NE)
Vitamin C
Reduces ferric to ferrous in stomach to increase iron absorption
Vitamin C
Deficiency will lead to scurvy
Vitamin C
