B vitamins Flashcards
What vitamin is the coenzyme for the decarboxylation of alpha keto acids (CAC and glycolysis) and for transketolase reactions (PPP). Making it essential for the conversion of carbohydrates to CO2 and energy and the normal functioning of the nervous system, skeletal muscles and heart. In order to perform its coenzyme functions.
B1 (Thiamin)
Needs in life cycle for B1?
There is a slight increase in need of Thiamin (B1) during each life cycle stage. Slight increase during pregnancy. Pregnancy and lactation needs stay the same.
What is needed for B1 absorption?
Magnesium
What can be more toxic with B1 deficiency?
Alpha-lipoic acid (ALA)
Food sources for B1?
Seeds Nuts wheat germ rice bran legumes meats (such as liver and pork) egg yolks poultry fish
What reduces B1 content?
Sunlight sulfites and nitrates cooking thiaminase (an enzyme found in raw seafood) tannins (found in tea and coffee)
What reduces the bioavailability of B1?
Reduced by concurrent consumption of ethanol, anti- thiamin factors, dietary fats and acidic beverages; exposure to radiation; and a number of medications.
B1 deficiency causes?
Chronic thiamin deficiency produces various forms of beriberi, with megaloblastic anemia, lactic acidosis, and branched-chain ketoaciduria; dry beriberi affects the nervous system, wet beriberi affects the heart and circulation. Chronic thiamin deficiency combined with alcoholism often produces the Korsakoff Syndrome of mental confusion, memory loss, delusions, and amnesia or Wernicke Disease (apathy, delusion, and delirium). These may appear concurrently as Wernicke-Korsakoff Syndrome (alcoholic dementia).
B1 drug-nutrient interactions?
alcohol, oral contraceptives, loop diurectics
What vitamin is required for the function of the electron transport chain and other reduction reactions, oxidation of amino acids and fatty acids, hydroxylation reactions of hepatic drug detoxification, condensation of acetate or pyruvate and coenzyme A to form acetyl CoA, and one-carbon transfers.
B2 the precursor for synthesis of flavin adenine dinucleotide (FAD)
Life cycle needs for B2?
There is a slight increase in need during each life cycle stage. Males 14 years of age or more need more than females 14 years of age or more. Slight increase during pregnancy. Lactation needs are slightly greater than pregnancy.
Nutrient partners for B2?
- HCL and enzymes-frees B2 from protein
- albumin, fibrinogen, and globulin-B2 is transported in the plasma via these.
- Flavokinase and FAD synthetase
- Aldosterone and thyroid hormone accelerate the conversion of riboflavin to coenzyme forms.
Nutrient Inhibitors for B2?
Calcium
B2 deficiency causes what issues to other nutrients?
-Alters iron metabolism
- can affect many enzyme systems such as:
• conversion of B6 to PLP
• Synthesis of NAD and NADP from trytophan
• The enzyme MTHFR (Methylene Tetrahydrofolate Reductase), which is required for maintaining folate coenzymes, and is needed for the conversion of methionine from homocysteine
What are higher levels of B2 associated with?
associated with decreased homocysteine (mainly
in those homozygous for C677T polymorphism and also in those with low folate intake)
Food sources for B2?
cheese yogurt eggs meat poultry fish beans spinach whole grains nuts currants asparagus broccoli avocados brussels sprouts The riboflavin content of foods is reduced by cooking, Pasteurization, evaporation, irradiation, drying, storage in clear glass bottles, sunlight, and milling.
What reduces the bioavailability of B2?
- reduced by cooking, Pasteurization, evaporation, irradiation, drying, storage in clear glass bottles, sunlight, and milling.
- Antimalarial drugs interfere with riboflavin bioavailability.
Drug-nutrient interactions for B2?
• alcohol inhibits absorption • Doxorubicin (Adriamycin) • Tricyclic antidepressants • Oral contraceptives • Antipsychotic (chlorpromazine) • Anticonvulsants • Antimalarial medication, Quinacrine and the chemotherapy agent, Doxorubin can decreased the incorporation of riboflavin into FAD and FMN.
B2 deficiency
Signs and symptoms of riboflavin deficiency include:
• Sore throat
• Redness and swelling of the mucosa in the mouth and throat
• Cheilosis (cracks and sores on the outside of the lips
• Angular stomatitis (cracks, sores at the corners of the mouth)
• Glossitis (inflammation and redness of the tongue)
• Seborrheic dermatitis (moist, scaly skin rash/inflammation)
• blurred vision
• light sensitivity
• eczema on the face and genitalia.
What vitamin is required for required for the synthesis of high-energy phosphate compounds, carbohydrate metabolism (glycolysis and the hexose monophosphate shunt), DNA metabolism (pyrimidine and purine biosyntheis), fatty acid oxidation, lipolysis, lipogenesis, cholesterol metabolism, vitamin metabolism, thyroxine synthesis, steroid synthesis, and norepinephrine and epinephrine synthesis.
B3
The major role of NADH, formed from NAD, is to transfer its electrons from metabolic intermediates through the electron transport chain (Figure 3.25), thereby producing ATP.
Life cycle needs for B3?
There is a slight increase in need during each life cycle stage. Increase during pregnancy and lactation. Pregnancy has a slight increase amount compared to lactation.
Nutrient partners for B3?
B2 for Synthesis of NAD and NADP from trytophan
and then trytophan
Food sources for B3?
eggs meat (especially liver) fish milk and cheese potatoes corn and corn products broccoli tomatoes carrots
Deficiency for B3?
Pellagra: Pellagra is known clinically by the ‘4Ds’: • Dermatitis • Dementia • Diarrhea • Death
Toxicity for B3?
Niacin is known to be safe at daily intakes up to 2 grams, although some individuals may experience facial flushing and mild discomfort at intakes greater than 500 mg.
Daily intakes greater than 1 gram inhibit VLDL production and may reduce serum total cholesterol concentration.
