vitaminsOrganicEssentialRequired in tiny amount to perform specific functions that : - promote growth - reproduction - maintenance of health and lifeVital to life ( vita amine )

Water soluble vitamins

AbsorptionDirectly into the bloodTransportTravel freely into the bloodStorageCirculate freely in water-filled parts of the bodyExcretionKidney detect and remove excess in urineToxicityPossible to reach toxic levels when consumed from supplementsRequirementsNeeded in frequent doses

Fat soluble vitaminsNote : Exceptions occur, but these differences between the water-soluble and fat-soluble vitamins are valid generalization

AbsorptionFirst into the lymph, before the bloodTransportRequire protein carriersStorageStored in the cells associated with fatExcretionLess readily excreted, tend to remain in fat-storage sitesToxicityLikely to reach toxic level when consumed from supplementsRequirementsNeeded in periodic doses (perhaps weeks or even months)

Vitamin A

Structures

Carotene, retinal and retinol

vit A in foodsSources - Preformed (Retinoid) liver, fish, eggs, fortified margarine etc. - Pro vitamin (Carotenoid) vegetables, fruits, carrotsConversion values 1 IU = 0,3 ug retinol = 3,6 ug beta carotene = 7,2 ug other dietary provit A

Conversion of vitamin A compounds

Function

Protein synthesisIntegrityReproduction and growthVision

Mechanism of the action on protein synthesisCarried by RBP in the bloodEnters the target cellEnters the nucleusBinds to its nuclear-retinoid receptorsThis complex binds to DNA, activating gene transcriptionThe resulting mRNA has the code for the proteinProtein synthesis

Mucous membrane integrityIt helps to maintain the skin and mucous membranes of the oral cavity and the digestive, reproductive, respiratory and urinary tracts

Role in visionRetinal, binds to the protein opsin to form rhodopsin, a visual pigment (found in the rods of the retina); this leads to black/white vision

The bleaching and regenaration of rhodopsin

xerophthalmia

Bagian mata yg bisa terkena xerophtalmia

Tahap-tahap xeroftalmia

Symptoms of deficiency and toxicity

Prevensi terhadap KVA

Vitamin D : cholecalciferolfound as ergocalciferol (D2) and cholecalciferol (D3)Both activated in plants/animal skin by UV radiation (conditional vitamine)D3 primarily used as precursor for calcium regulationDeficiency : bone deformation (rickets)An excess of vitamin D can lead to hypervitaminosis resulting in renal failure, weight loss, and calcification of soft tissues in the body

Rickets

Vitamin E: tocopherolactive form is alpha tocopherolgood antioxidant Deficiency - nervous system damage. - reduced Immune function - fragile red blood cellsoverdosing: diarrhea, nausea, headaches, fatigue

Vitamin K: menadioneOriginally identified as a fat-soluble factor required for normal blood clottingmenadione is the most active formactually works by activating blood-clotting proteinsDefic. occurs when a person takes antibiotic (certain type), or has impaired fat absorptionAlso occur in newborn, typically low birth weight

Water Soluble VitaminsThese are vitamins that are also needed in small amounts due to their role in enzymatic reactions in the cellsAfter being ingested, they undergo chemical modifications which convert them into enzymesTaking larger doses of these vitamins is pointless because they are not stored in the body; they are excreted out in the urine

ThiaminThere is present in rice polishing a substance different from protein and salts, which is indispensable to health and the lack of which causes nutritional polyneuritis

C. Eijkman and Grijns

Thiamin B1Chief function : Part of co E TPP (Thiamin Pyrophosphate) in the metabolism of CHODeficiency : manifest chiefly as neuromuscular disordersSymptoms : Beri-beri, enlarged heart, cardiac failure, weakness, apathy, poor short term memory, anorexia, weight lossWernicke-Korsakoff syndrome (alcoholism)

Riboflavin: B2Chief function: part of FMN (flavin mononucleotide), FAD (Flavin adenine dinucleotide) used in energy metabolismRiboflavin co E have redox reaction functionDeficiency : manifested chiefly as dermal and neural disordersSymptoms : sore throat, cracks and redness at corners of mouth, painful, smooth, purplish red tongue

Riboflavin deficiency lesions of the margin of the lips (cheilosis) and corners of the mouth (angular stomatitis) painful desquamation of the tongue, so that it is red, dry and atrophic (magenta tongue) sebhorroeic dermatitis, with filiform excrescences.

Deficiency is widespread; rarely fatal because there is efficient reutilization of riboflavin released in catabolism of enzymesRiboflavin functions as a redox coenzyme in all energy-yielding pathways

Niacinforms: niacin, nicotinic acid, nicotinamidethe co E form : niacin, NAD and NADP are active participants in redox reactions. sources: rice polishings, yeast, rice brantryptophan can be converted to niacin in the body.deficiencies: pelagra, dermatitis, anemia (fish), skin lesions (fish), sunburning (fish)

Pellagra the niacin deficiency diseaseSunburn-like dermatitis in areas exposed to sunlight

Niacin deficiency (pellagra) before and after therapy

Pyridoxine (B6)

Generic descriptor for all 3-hidroxy-2-methylpyridine derivatives exhibiting qualitatively the biological activity of pyridoxine.The metabolically active form of B6 is pyridoxal phosphate, which functions as a co E for reactions involving amino acids Required for synthesis and breakdown of amino acidsFound in fish, meat, poultry, leafy green vegetablesRDA: ~2.0 mg/dayDeficiency: rare, nervousness/muscular weaknessOverdose: if 50-100 times the RDA are taken peripheral neuropathy in young women has been seen

Pantothenic AcidEssential for the normal metabolism of fats and carbohydratesAbundant in meat, poultry, whole grain cereals and legumesRDA: 4-7 mg/dayDeficiency: rare, except in alcoholics, leads to gastrointestinal, neuromotor, and cardiovascular disordersGets converted to CoA in the body (the functional form); also important in fatty acid metabolism

BiotinInvolved in carboxylation/decarboxylation reactions in the metabolism of fats, carbs, and proteinSources: liver, egg yolks, cheese, peanuts, bacteria in the intestinesDeficiency: rare, dermatitis, loss of appetite/nausea, muscle pain, elevated blood cholesterolBirth defect : labioplatoschisis, short limbs, etc.

Folic AcidRecently shown as very important for pregnant females to avoid birth defectsfunction: synthesis of purines, pyrimidines, nucleic acidsdeficiencies: - megaloblastic anemia - Neural Tube Defect (NTD). - CVD

Folate absorption and activation

Folate in nucleic acid metabolism

Efek defisiensi folat di tingkat molekuler

Folic acid

Neural Tube Defects: How Do They Occur?Babys brain and spine fail to close completelyNeural tube closing properlyto form spinal column and brain.

Anencephaly Upper end of the neural tube fails to close Brain either never completely develops or is totally absent.

Spina Bifida Neural tube fails to close on lower end

Spinal cord and back do not develop properly

Folic acid and cardiovascular diseasefolic acid increases blood folate levelslowers homocysteine levelselevated homocysteine levels associated with cardiovascular disease and stroke

Folate and cancer

Growing evidence suggests that folate deficiency in normal epithelial tissues may predispose individuals to developing neoplasms in these tissues.

Low folate status may play a role in early carcinogenesis

CyanocobalmineLast of 15 vitamins to be identified chemically complex, cobalt nucleusfunction: coenzyme in metabolic reactions, maturation of erythrocytes, uracil->thyminedeficiency: pernicious anemia, nerve disorders

TCA CYCLE

B vitamins-in CHO metabolism concert

Ascorbic Acid: Cfunction: antioxidant, stress reducer, bone calcification, iron metab, tyrosine metab, blood clottingImportant for growth/repair of connective tissue, teeth, bones, and cartilagePromotes wound healing, enhances absorption of iron, helps synthesize several hormonesdeficiency: stomatitis, scorbut, slow woun healingtoxicity: nausea, diarrhea kidney stone

Vitamin-like SubstanceCholineTaurineCarnitineMyo-inositolBioflavonoidsLipoic AcidCoenzym Q (Ubiquinone)

CholineWater soluble compound, vital to structural integrity of biologic membranes Constituent of phosphatidylcholine (lechitin), sphingomyelin and acetylcholineWidely available in food supply

TaurineAmino acidFunction: neuromodulation, stabilization of cell embranes, osmotic regulationCan be synthesized from cystein or methionineAbundant in meat and seafood

CarnitineA nitrogenous compound synthesized from lysine and methionine in the liver and kidneyFunction: trans-esterification reaction and transport of long chain FA into mitochondriaSynthesized adequately in adult, human milk delivered sufficient amount of carnitineDeficiency due to inborn error of metabolism: muscle weakness, cardiomyopathy and hypoglycemiaSource: meats and dairy

Myo-inositolAn alcohol, structurally similar to glucoseConstituents of phospholipids in membranes and essential for the replication of human cellsFound in cereal grains, can be synthesized from glucose

BioflavonoidsWater solublePhenolic compounds in plantsInfluence capillary permeability and fragilityFound in tea, wine, citrus fruits

Lipoic AcidFat solubleRelated to B vitaminsFunction: co-enzyme

Coenzyme Q (Ubiquinone)A group of lipid-like compound, structurally related to vit EFunction: mitochondrial electron transport

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