Lipid Soluble Vitamins Flashcards
Symptoms including increased intracranial pressure, headaches, double vision, dizziness, bone and joint pain, hair loss, dermatitis, hepatosplenomegaly, diarrhea and vomiting.
Can cause teratogenicity, and it should be avoided during pregnancy.
Vitamin A Excess
Retinal can be converted by the body to:
Retinoic Acid
Is synthesized by UV radiation of ergosterol in plants and fungi
Vitamin D2 (ergocalciferol)
Disrupts the mineralization of newly formed osteoid as a result of decreased calcium and phosphate availability and reduced osteoblast function
Calcitriol deficiency
Is a mixture of several compounds, known as tocopherols.
Vitamin E
Its is the most toxic of all vitamins
Vitamin D
Vitamin 125-(OH)2D3 diffuse across the plasma membrane, and the fraction bound to DBP is transported actively by:
Megalin or Cubulin
Bind the 9- cis isomer only
Rexinoid Receptors (RXR)
Is a group of compounds that vary in the number of isoprenoid units in their side chain.
Vitamin K
Can be found in fish (D3), whereas that used for fortification is often D2 (ergocalciferol).
Vitamin D
Is required for post-translational modification of coagulation factors (factors II, VII, IX, and X).
Vitamin K
All dietary forms of vitamin A are converted to ________ wich in turn, can be converted to __________
Retinol > Retinoic Acid
Produces the inactive 24,25-dihydroxycholecalciferol (24,25[OH]2D3).
CYP24A1 found in renal tubules, cartilage, intestine and placenta
b-carotene and other carotenoids that can be converted by the body into retinol are referred to as ________________
Provitamin A Carotenoids
Is secreted from the liver bound to serum retinol-binding protein (RBP) and is taken up by cells via a membrane receptor.
Retinol
Who is the key 1-hydroxylase?
CYP27B1
Is synthesized in the skin by UV irradiation of 7-dehydrocholesterol.
Vitamin D3 (cholecalciferol)
Bind both all- trans-and 9- cis-retinoic acid
Retinoid Acid Receptors (RAR)
Vitamin D ingestion recommendation are:
600 IU/day for adults < 70 years, and 800 IU > 70 years.
Intake > 4,000 IU/day, could be a risk for heath
Its dietary sources are green leafy vegetables, fruits, dairy products, vegetable oils, and cereals.
Vitamin K
Is absorbed from the diet in the small intestine with lipids
Vitamin E
_____________ contains 10 of carboxylated residues, and all are required for this protein’s specific chelation of Ca2+ ions during its function in the coagulation process.
Prothrombin (factor II)
Is trasnported to the liver, where it is hydroxylated at the 25-position forming calcidiol
Vitamin D3
Type I results from abnormalities in the gene coding for 25(OH)D3-1-α- hydroxylase, and type II results from defective vitamin D receptors.
Vitamin D-Dependent Rickets
Antithrombotic drugs are:
Inhibitors of vitamin K action
The 1α-hydroxylase is stimulated by:
PTH, by low plasma concentrations of calcium or phosphate, and by calcitonin as well as by estrogens and by vitamin D deficiency.
Is also produced by the intestinal microflora.
Vitamin K
In premature infants, the deficiency of Vitamin E causes
Hemolytic anemia, thrombocytosis, and edema, as well as peripheral neuropathy, myopathy, and ataxia.
Hemorrhagic disease of the newborn
Premature infants disease because of Vitamin K deficiency
If a person takes in too much of a lipid soluble vitamin, over time they can have too much of that vitamin present in their body, a potentially dangerous condition called:
Hypervitaminosis
Transported to cells bound to either albumin or a specific retinoic acidbinding protein (RABP).
Retinoic Acid
What can cause high doses of Vitamin D?
High doses result in hypervitaminosis D, deposition of Ca2+ in soft tissue (kidney, heart, lungs and vasculature), hypercalcinuria, and possible kidney stones.
Warfarin
Inhibitor of vitamin K action
The richest sources of naturally occurring vitamin E are:
Vegetable oils, nuts, and green leafy vegetables.
Develops when growing bones fail to mineralize or can be cause nutritionally by inadequate intake of nutrients (vitamin D in particular)
Rickets
Name the symptoms of Vitamin K deficiency
Easy or excessive bleeding Easy or excessive bruising Nosebleeds Bleeding gums Blood in urine and stools Extremely heavy menstrual bleeding Liver damage or disease Low Bone Density Arterial Calcification
Lipid soluble vitamins are considered to be hormones rather than vitamins since they do not play coenzymatic functions, with the exception of: ________________
Vitamine K
Is involved in immune function, cellular signaling, and gene expression.
Vitamin E
Esterified in the liver by lecithin:retinol acyltransferase and stored in the form of retinyl esters (retinol palmitate), bound to the cytosolic retinol-binding proteins (CRBP).
Vitamin A
The synthesis of 1,25(OH)2D3 from 25(OH)D3 is stimulated by__________ and suppressed by_____________.
Parathyroid
hormone (PTH), Ca2+, Pi and 1,25(OH)2D3 itself.
Is important in role in growth, differentiation, and proliferation of cells; in embryonic development and organogenesis; and also in the maintenance of epithelia.
Retinoic Acid
Rarely, deficiency may develop in those with liver disease or fat malabsorption.
Vitamin K Deficiency
Its deficiency produces defective epithelialization and corneal softening and opacity (keratomalacia).
Vitamin A Deficiency
Is a signaling molecule. It interacts with ligand-activated transcription factors, known as the nuclear retinoid receptors.
Retinoic Acid
Deficiency causes bleeding disorders
Vitamin K Deficiency
How are transported and absorbed the lipid soluble vitamins vitamins?
Absorbed as mixed micelles and transported as chylomicrons that travel through the lymphatic system of the small intestines and into the general blood circulation within the body.
It protects lipids from oxidation by the reactive oxygen species (ROS).
Vitamin E
Maintain normocalcemia through optimizing intestinal calcium absorption, even at the expense of skeletal mineralization.
Vitamin D Central Role
Vitamin D3 binds to ________ so he can be transported to liver.
Vitamin D-binding protein
Ninety percent of vitamin E present in human tissues is in the form of: _____________
α-tocopherol
Which health outcomes has been linked to low vitamin D levels during pregnancy and infancy?
Preeclampsia, low birth weight, neonatal hypocalcemia, poor postnatal growth, bone fragility, and increased incidence of autoimmune diseases
Deficiency presents as night blindness
Vitamin A Deficiency
Is the most potent of the vitamin D metabolites because is the ligand for the vitamin D receptor (VDR)
Calcitriol
Vitamin D is stored in the body as:
25-OHD3 (half life about 20-29 days)
Deficit in the lipid soluble vitamins can be caused by:
Low fat intake, compromised fat absorption or cystic fibrosis
Over consumption of Vitamin D, because calcium deposits, can cause damage to elastic fibers and smooth muscle leading the patient to:
Atherosclerosis
_______ is a generic term
for retinol, retinal, and retinoic acid. Retinal and retinoic acid are their active forms
Vitamin A
Vitamin K circulates as _______, and its hepatic stores are in the form of __________.
Phylloquinone (vitamin K1), menaquinones (vitamin K2)
Is synthesized in the skin by ultraviolet (UV) radiation
Vitamin D
Its deficiency produces rickets in children and osteomalacia in adults.
Vitamin D
VDR regulates genes for the regulation of:
Cellular proliferation, differentiation, apoptosis, and angiogenesis.
Rate limiting step in catabolism of vitamin D3 is mediated by :
24-hydroxylase (24-OHase)
The gut of the newborn is sterile; therefore for several days after birth, there is no source of: ___________
Vitamin K
Is stored in the liver and needs to be transported to its sites of action, can provide 1 year’s supply
Vitamin A
Modulates growth, participates in immune function, and is antiinflammatory.
Vitamin D
In the renal tubules, calcidiol is further hydroxylated at the 1-position to form: _______________
Calcitriol
Is a hormone, and in addition to its role in calcium homeostasis, it influences genes involved in cell proliferation, differentiation, and apoptosis.
Vitamin D
Is the most important 25- hydroxylase
CYP2R1
Virtually ensures that dietary deficiency does not occur in humans, except for newborn infants.
Vitamin K supply by the intestinal microflora
Stimulates bone resorption by osteoclasts
Calcitriol & PTH
Upregulates gut Ca2+ channel TRPV6, the intracellular transporter calbindin D, and the calcium pump PMCA1b, increasing the transport of Ca 2+ from enterocytes to plasma.
Vitamin D3
The most abundant natural antioxidant, and because of its lipid solubility, it is associated with all lipid-containing structures: membranes, lipoproteins, and fat deposits.
Vitamin E
