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99 Cards in this Set
- Front
- Back
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2 types of vitamins!
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-Water soluble
-Fat soluble |
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What are the fat soluble's?
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DEAK
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What are the water solubles?
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Vit C
B vitamins |
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What is fat-soluble vitamin absorption dependent on?
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-Pancrease
-Ileum gut |
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What causes fat-soluble vitamin deficiencies?
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Malabsorption - Steatorrhea
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3 causes of malabsorption / steatorrhea:
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-Cystic fibrosis
-Sprue (celiac enteropathy) -Mineral oil intake |
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What is more commonly seen with Fat-sol vitamins than water-sol and why?
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Toxicity - they ACCUMULATE in fat
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What in fact happens to the water soluble vitamins?
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They wash out rather easily!
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What is the only water-sol vitamin that DOES NOT deplete easily by washing out? Why?
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B12 - cobalamin; the liver stores a year-long supply
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3 general symptoms of B-complex deficiencies:
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-Glossitis
-Dermatitis -Diarrhea |
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What are 2 symptoms of vitamin A deficiency?
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-Dry skin
-Night blindness |
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Function of Vit A:
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-Component of VISUAL PIGMENTS in the retina
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What are 6 symptoms of Vit A EXCESS?
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FASSHA
Fatigue, Arthralgias, Sore throat, Skin changes, HA, Alopecia |
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What is the source of Vit A?
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Green leafy veggies
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What is vitamin a used for topically? AkA?
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Wrinkles and Acne - Retinol
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Vit D2; source
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Ergocalciferol - in MILK
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Vit D3; source
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Cholecalciferol - in sun-exposed skin
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Storage form of Vit D:
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25-OH D3
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Active form of Vit D:
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1,25-diOH vit D3
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3 results of Vit D deficiency:
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Rickets - bending bones in kids
Osteomalacia - bones breaking in adults Hypocalcemic TETANY |
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Function of Vit D:
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Increases serum Ca and PO4
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3 signs of vit D EXCESS:
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-HYPERcalcemia
-Stupor -Loss of appetite |
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What is a condition in which Vit D excess can occur? WHY?
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Sarcoidosis! The epithelioid macrophages secrete vit D in its ACTIVE FORM!
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Function of Vit E:
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Antioxidant
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Where are the antioxidant actions of Vit E import?
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Erythrocytes - prevents hemolysis
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What are 2 signs of Vit E deficiency?
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-Increased RBC fragility
-Neurodysfunction |
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Function of Vit K:
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Cofactor for the enzyme y-glutamyl-Carboxylase which carboxylates terminal glutamic acid residues of clotting factors
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What is necessary for keeping Vit K in its reduced form, which is the active form in which it functions?
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Vitamin K epoxide reductase
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What is the SOURCE of Vit K?
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Intestinal flora
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So what can cause iatrogenic Vit K deficiency?
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Antibiotics!
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What is the result of Vit K deficiency?
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Increased PT/PTT
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In what patients can vit K deficiency particularly cause hemorrhage? Why?
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Neonates - they lack gut bacteria at birth; so you have to give Vit K injections!
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3 signs of ZINC deficiency:
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-HEALING of wounds delayed
-HAIR deficiency (pubic) -Hypogonadism |
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What can Zinc deficiency predispose patients to?
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Alcoholic cirrhosis
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What are the B vitamins?
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B1 = Thiamine
B2 = Riboflavin B3 = Niacin B5 = Pantothenate B6 = Pyridoxine B7 = Biotin B9 = Folate B12 = Cobalamine |
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What is the other water-sol vitamin?
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Vitamin C - ascorbate
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What is Vitamin B1 a cofactor for? What 2 conditions does deficiency cause?
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Thiamine Pyrophosphate TPP
-Wernicke-Korsakoff -Beriberi |
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What is DRY beriberi?
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DMP
Dry Muscle wasting/Polyneuritis |
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What is WET beriberi?
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HEW
-High-output Dilated Cardiomyopathy (heart failure) -Edema |
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In what 2 conditions are Beriberi and Wernicke-korsakoff seen?
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-Alcoholics
-Malnutrition |
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What is TPP a cofactor for?
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1. Pyruvate dehydrogenase - conversion of Pyruvate to AcCoA
2. Transketolase |
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What is transketolase?
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The nonoxidative enzyme that is reversible and makes Ribose5P, G3P, and F6P in the HMP shunt.
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What is Ribose5P for?
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NT synthesis
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What are 3 signs of Vit B2 deficiency of Riboflavin?
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-CHEILOSIS
-CORNEAL vascularization -Angular stomatitis |
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What is Riboflavin's function? What is it a component of?
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Oxidation/Reduction cofactor as FADH2; in FAD and FMN
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How many ATP are synthesized per FADH2?
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2 ATP from vitamin B2!
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And how do you remember the symptoms of Vit B2 deficiency?
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2C's - Cheilosis and Corneal vascularization
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What is Cheilosis?
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Same thing as angular stomatitis.. ohhh
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What is the function of Vit B3?
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Component of NAD/NADP - for REDOX reactions
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What are NAD and NADP made from? With what cofactor?
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Tryptophan - via an enzyme that requires vit B6, Pyridoxine!
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How can you remember what Vit B3 is?
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NADH gives 3 ATP - from vit B3
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In what disease is Tryptophan deficient, and what does this cause?
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Hartnup disease - impaired Tryptophan absorption causes PELLAGRA
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What are the 3 classic symptoms of Pellagra?
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3 D's
-Diarrhea -Dementia -Dermatitis (and beefy glossitis) |
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What are 2 other causes of Vit B3/Niacin deficiency? How?
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-Carcinoid syndrome - increases Tryptophan METABOLISM
-Isoniazid - decreases Vit B6 |
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What is almost always given in conjunction with Isoniazid to prevent peripheral neuropathy?
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Pyridoxine - so that you don't lose Vit B3 too!
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So the 3 causes of Vit B3 Niacin deficiency are:
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-Hartnup disease/Pellagra
-Malignant Carcinoid syndrome -INH/lack of Vit B6 |
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What is B5?
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Pantothenate
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What are Pantothenate's 2 functions?
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-Cofactor for Acyl transfers - it is a component of Coenzyme A
-Fatty acid synthase - FAS |
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What are 4 signs of Pantothenate deficiency?
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ADEA
-Alopecia -Dermatitis -Enteritis -Adrenal insufficiency |
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Why would lack of Pantothenate cause Adrenal Insufficiency?
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Because you need AcCoA and fatty acid synthesis for Steroid hormone synthesis
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What is vit B6 a component of and a cofactor for?
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Pyridoxal Phosphate: for
-Transamination - ALT/AST -Decarboxylation -Heme synthesis |
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What are 3 signs of Pyridoxine B6 deficiency?
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-Hyperirritability
-Peripheral neuropathy -Convulsions |
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What 2 drugs can induce B6 deficiency?
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-INH
-Oral contraceptives |
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What are the 2 reactions that Vit B12/Cobalamin is essential for?
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-Homocysteine methylation
-Methylmalonyl-CoA handling |
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What role does Vit B12 play in homocysteine methylation? What is the product?
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Transfers methyl groups from N-methyl THF to Homocysteine to make Methionine
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What role does Vit B12 play in Methylmalonyl CoA handling?
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Cofactor for conversion of Methylmalonyl CoA to SuccinylCoA
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What is the source of B12 and where is it stored?
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Source is ANIMAL PRODUCTS from microorganisms!
Stored in liver - enough for SEVERAL years! |
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What are the 3 most common causes of Vit B12 deficiency?
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-Malabsorption
-Pernicious anemia -Absence of Terminal Ileum |
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3 causes of Malabsorption:
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-Sprue
-Enteritis -D. latum |
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What is Pernicious anemia?
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Lack of intrinsic factor
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What causes absence of the terminal ileum?
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Crohn's disease
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What DOES lack of Vit B12 result in?
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-Megaloblastic anemia
-Megaloblastic MADNESS -Glossitis |
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What is Megaloblastic neurologic dysfunction characterized by?
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-Subacute combined degeneration
-Parasthesia -Optic neuropathy |
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What is the MOST COMMON vitamin deficiency in the US?
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Folate deficiency
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What results from Folate deficiency?
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Megaloblastic anemia
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How does the Megaloblastic anemia due to Folate defic differ from that in B12 defic?
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No neurologic symptoms in Folate deficiency!
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What is the SOURCE of Folate?
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FOLiage - green leafy veggies
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What do you need to do in pregnancy?
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SUPPLEMENT folate to reduce neural tube defects
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What is the function of Folate?
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THF - 1 carbon donors in methylation reactions
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What are the 1-carbon transfers important for synthesis of?
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Nitrogenous bases in DNA/RNA
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What is the Folic acid precursor in BACTERIA?
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PABA
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What antibacterial drugs are PABA analogs that inhibit Folate Synthesis?
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Sulfa drugs (Sulfamethoxazole)
Dapsone |
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And what is the other water-soluble vitamin?
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Vitamin C - ascorbate
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What is Vit C deficiency called?
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Scurvy
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4 signs of Scurvy:
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-Poor wound healing
-Anemia -Bruising -Swollen gums |
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What are three functions of Vit C?
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1. Hydroxylation of Pro/Lys in collagen (cofactor)
2. Keeps Fe2+ in reduced state to facilitate iron absorption 3. Cofactor for DA->NE |
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What are the steps in Ethanol metabolism? Enzymes?
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1. Alcohol Dehydrogenase converts Ethanol to Acetaldehyde
2. Acetaldehyde Dehydrog makes Acetaldehye -> AceTATE |
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What cofactor is necessary for both ADH and ALDH?
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NAD+
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What is the rate limiting reagent in Ethanol metabolism?
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NAD+
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What can happen to ADH and how?
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Saturation - it operates by zero-order kinetics
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What drug inhibits ALDH and what is the result?
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Disulfiram - Antabuse; build up of Acetaldehyde -> symptoms of hangover worse; makes you not want to get drunk!
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What results when Ethanol metabolism is greatly increased?
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NADH/NAD+ ratio builds up
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What effect does increased NADH/NAD+ ratio have on metabolism?
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-Pyruvate shifts to lactate
-OAA shifts to Malate Less is available for gluconeogenesis; HYPOGLYCEMIA |
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What does Ethanol hypoglycemia lead to in chronic alcoholics?
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Fatty Liver - more FA synthesis, less glycolysis.
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Kwashiorker:
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PROTEIN deficiency
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Marasmus:
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CARBOHYDRATE deficiency
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What causes Kwashiorker and what results?
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MEAL that is protein-deficient:
-Malabsorption -Edema -Anemia -Liver that's fatty |
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What is the clinical picture of Kwashiorker?
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A child with a swollen belly
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What are the 3 results of energy malnutrition in MARASMUS?
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-Tissue/Muscle Wasting
-Loss of subcutaneous fat -Variable edema |
