Vitamins and Minerals Flashcards
Nutritional status is determined by 3 factors:
Biological, psychological, and social factors
- This factor of nutritional status includes things like the availability of food and cultural customs
- This one includes the desire to eat, appetite, and the palatability of foods
- This one includes genotype (sex), digestion, absorption, metabolism, and excretion of nutrients, age and phase of the life cycle
- Social Factors
- Psychological
- Biological
Which part of the brain translates signals related to energy balance for the stomach, pancreas, and adipose tissue into eating behavior?
Hypothalamus
What signal does the stomach transmit to the hypothalamus which regulates eating behavior?
Ghrelin
What signal does the pancreas transmit to the hypothalamus which regulates eating behavior?
Insulin
What signal does adipose trasmit to the hypothalamus which regulates eating behavior?
Leptin
When the hypothalamus transmits Neuropeptide Yi, agouti related peptide, what happens?
+ (increase of appetite)
When the hypothalamus transmits propiomelanocortin, it triggers MSH (melanocyte stimulating hormone), which leads to what?
- (decrease in appetite)
The main role of vitamins and minerals is participation in enzymatic reactions as either _____ or ______________
- Cofactors
- Components of enzymatic prosthetic groups
- What does the EAR represent in the graph?
- What does RDA represent?
- Estimated Average Requirement of enough intake for 50% of the population
- Recommended daily allowance for the great majority of individuals (except for 2 to 3 percent of individuals)
- What does UL represent in the graph?
- Does the AI (adequate intake) bear any relationship with EAR or RDA?
- At an intake above it, the risk of adverse affects increases (too much vitamin is bad)
- No, it is based on an estimate of nutrient intake in healthy people
These figure contains the current recommendations on healthy eating, one developed by the US Department of Agriculture replacing the food pyramid. The other by the Food Standards Agency UK
My Plate (US) and Eatwell Plate (UK)
Any of a group of substances that is required in small quantities for the normal functioning of metabolism in the body. They cannot usually be synthesized in the body but they occur naturally in certain foods. Insufficient supply of them results in deficiency disease.
Vitamins
Thiamine (vit B1) deficiency disease is called..
Beriberi. Sources include seeds, wheat germ, lean meat, legumes
Riboflavin (vit B2) deficiency disease is called…
Pellagra (meats, nuts legumes)
Niacin (vit B3) deficiency disease is called
Pellagra as well (meats, nuts legumes)
Pyridoxine (vit B6) deficiency results in…
Neurologic Disease (yeast, liver wheat germ, nuts, beans, bananas)
Biotin deficiency results in…
Widespread injury (corn, soy, egg yolk, liver, kidney, tomatoes)
Folate deficiency disease leads to…
Megaloblastic Anemia
-caused by reduction in purine and pyramidine synthesis
Colabamin (vit B12) deficiency disease is
Pernicious anemia
can also cause:
Megaloblastic Anemia
-caused by reduction in purine and pyramidine synthesis
This is ascorbic acid, it is required for the mainenance of connective tissue and wound healing.
Vitamin C
Vitamin C is an essential cofactor for _____ and __________ which modify collagen. Without this modification the collagen triple helix is not stable
Lysyl and prolyl carboxylase
- Deficiency of vitamin C results in ______ (sore fragile gums, loose teeth, fragile blood vessels, swollen joints, anemia)
- Vitamin C has antioxidant properties and also helps in the absorption of…
- Scurvy
- Iron
What is this a picture of?
Scurvy. Hemorrhagic gingival enlargement due to capillary fragility
Vitamin C assists in the _______ of proline and lysine residues in collagen.
Hydroxylation
This is Thiamine deficiency and is found where polished rice is a major source of food. Rapid onset occurs in infants often if the mother is deficient. It’s common in the 3rd world.
Beriberi
Niacin deficiency results in ________, which is characterized by dermatitis, GI disturbances, neurologic and mental disturbances, glossitis, gingivitis, generalized stomatitis.
Pellagra
- Pellagra is rare but can also be caused by _____ or ______
- What two things may be the earliest sign of pellagra?
- The gingiva may be involved with or without tongue changes, the most common finding is….
- Malabsorption or alcoholism
- Glossitis and stomatitis
- Necrotizing ulcerative gingivitis
Biotin deficiency usually does not occur alone but could be part of a general deficiency of __________ due to malnutrition or alcoholism
B vitamins
This vitamin plays a key role in one carbon metabolism (methyl), and is essential for the synthesis of several compounds. There is an increased chance for deficiency during pregnancy due to the rapid growth and division taking place.
Folic Acid (VitB9)
- Foilc acid is often attached to a __________
- After absorption the ________s are removed
- Free folate is then converted into _________ by dihydrofolate reductase
- The aforementioned molecule receives one carbon fragments from donors such as serine, glycine, and histidine for use in the synthesis of ______s
- Polyglutamate Tail
- Amino Acids
- Tetrahydrofolate
- Amino acids, purines, and thymine
This vitamin is also involved in chemotherapy, by limiting cells’ ability to differentiate
Folic acid (folate, Vit B9)
One result of folate deficiency is _________ caused by a reduction in purine and pyrimidine synthesis
Megaloblastic anemia
This is the most common vitamin deficiency in the US, it can be caused by increased demand, poor absorption in intestine, or treatment with methotrexate
Folate
- Common neural tube defects are _____ and _____
- Supplements of what, before and during the first trimester of pregnancy, virtually eliminate the risk?
- Spina bifida and anencephaly
- Folate
- Too much folate can cause deficiency in…
- This can lead to…especially in the elderly
- Vitamin B12
- Megaloblastic anemia
This vitamin is synthesized by microorganisms and is not present in plants. It contains cobalt coordinated to a corrin ring
Cobalamin (VitB12)
- Colabamin is required for the synthesis of _______
- It is also required for the isomerization of _____, produced by the degradation of some AAs and odd number fatty chain acids
- Methionine
- ethylmalonylCoA
This molecule is essential in getting VitB12 into the bloodstream from the intestine. You don’t make as much of it as you age, lessening B12 absorbance overall.
Intrinsic Factor (IF)
This molecule delivers B12 to the tissues from the blood stream
TCII
Colabamin deficiency is usually rare as it is present in many foods, however, deficiencies in absorption are more common. When it occurs, it results in ______ after a significant period of time due to stores in our body
Pernicious anemia.
The pernicious anemia resulting from deficient colabamin absorption is caused by a reduction in _______
Intrinsic Factor (IF)
- Colabamin deficiency results in a decrease of ______
- This results in a decrease of the synthesis of ____ and _____
- This leads to….
- Hence it can look like ____ deficiency
- Tetrahydrafolate
- Purine and thymine synthesis
- Megaloblastic anemia
- Folate
- In colabamin deficiency, neurological effects also occur probably as a result of defects in ___________ metabolism atlering membrane lipid structure
- Fatty acid metabolism
In colabamin deficiency, myelin sheath formation is altered perhaps because ____________ inhibits fatty acid synthesis, and also because it’s used to make unusual branched chain fatty acids
methylmalonylCoA
- VitB12 and folate are involved in the conversion of homocysteine to _______
- An absence of _________ leads to the build up of N5MeTHF, known as the tetrahydrofolate trap
- methionine
- Vitamin B12
This is a collective term for pyridoxine, pydridoxal, and pyridoxamine. All are precursors of pyridoxal phosphate, a coenzyme for many enzymes, especially those involved in metabolism
Pyridoxine (Vitamin B6)
What are the fat soluble vitamins?
Vitamin A, D, E, K,
This vitamin is related to the retinoids, and is derived from plant carotenoids (ß-carotene). Carrots and dark green veggies are a good source
Vitamin A
The eye requires _____ to make 11 -cis retinol which binds to opsin to make rhodopsin
Retinol
Deficiency in this vitamin causes night blindness and xerophthalma (dryness of cornea and conjunctiva, blindness)
Vitamin A
Retinoids can affect growth and development by affecting __________, similar to the way steroid/thyroid hormones work. They go into the nucleus and bind.
Gene transcription
This fat soluble vitamin is a mixture of 8 forms of tocopherol, the most active being α-tocopherol. They are important antioxidants found in vegetable so deficiency is rare. Mostly found in premature infants.
Vitamin E
Are vitamin E supplements effective against heart disease or cancer?
NO! They can actually damage heart valves
This fat soluble vitamin is a quinone derivative found in vegetables and synthesized by guy bacteria.
Vitamin K
Vitamin K is essential for ___________ of coagulation factors, it creates two carboxylic acid groups which can bind to calcium much more easily
γ-carboxylation
Anticoagulants of the _____ family inhibit the γ-carboxylation reaction that vitamin K is involved with
Warfarin
This mineral occurs in bone, but is also essential in controlling intracellular processes, including muscle contraction. Regulation of its metabolism is essential.
Calcium
Most of the calcium in our body is in what form?
Ionized (free, biologically active)
These vitamins are steroid derivatives which have a hormone like function.
Vitamin D
- Precursors of vitamin D include from plant sources
- Precursors from animal tissues
- Ergocalciferol (D2)
- Cholecalciferol (D3)
- In the endogenous generation of vitamin D, 7-dehydrocholesterol is converted to _________ by sunlight
- Where does this occur?
- Cholecalciferol (D3)
- Dermis and epidermis of the skin
After being generated in the dermis and epidermis of the skin, , or converted from D2, cholecalciferol (D3) is transported from the skin to the ______
Liver
In the liver, cholecalciferol is converted to _____, the main storage form of the vitamin.
25-hydroxy D3
From the liver, after being converted to 25-OH D3, where does D3 travel to?
The kidney
What is 25 OH D3 converted to in the kidney?
1,25 dihydroxycholecalciferol (1,25 diOH D3)
What enzyme in the kidney converts 25 OH D3 to 25 diOH D3?
25-hydroxycalciferol 1-hydroxylase
25-hydroxycalciferol 1-hydroxylase, the enzyme in the kidney which converts 25 hydroxycholecalciferol to 1,25-dihydroxycalciferol, is activated directly by low plasma ________ and indirectly by low plasma ________
Directly by low plasma phosphase, indirectly by low plasma calcium
Low plasma phosphate or low blood calclium activate 25-hydroxycalciferol 1-hydroxylase, which stimulates the release of…
Parathyroid hormone (PTH)
- Low blood Ca2+ in the serum stimulates _______ to create 1,25 hydroxycalciferol (biologically active calcitrol)
- High blood Ca2+ stimulates _______ to produce biologically inactive 24,25-hydroxycalciferol
- 1 α-hydroxylase
- 24-hydroxylase
- In the duodenum (the first part of the small intestine), _____ binds to cytosol and nuclear receptors in enterocytes
- This induces the synthesis of a calcium binding protein called…
- Calcitrol
- Calbindin
- This calcium binding protein transports calcium across the enterocyte and through a Ca2+ insensitive ATP-ase channel to the blood stream
- What kind of transport is this?
- Calbindin
- Active Transport
- In these two places, Ca2+ is transported across the cellular membrane into the blood
- What type of transport is this?
- Jejunum and Ileum
- Passive transport
- A decrease in blood plasma Ca2+ leads to the stimulation of the secretion of what?
- What 3 places does it go to to increase Ca2+absorption?
- In the kidney, what does it increase the synthesis of?
- PTH
- Intestine, Kidney, Bone
- (1,25) OH2 D3
Once PTH has caused increased absorption in the kidney, intestine, and bone, thus raising the blood Ca2+ concentration, what is realized to stop the effects of PTH?
Calcitonin
What 2 effects does this synthesis of parathyroid hormone have in the blood?
- Increases blood serum Ca2+
- Decreases serum phosphate
What 4 effects does PTH have in the liver?
- Increases cAMP
- Increase Ca2+ absorption
- Increases dihydroxy D3
- Decreases phosphate reabsorption
What two cells does PTH affect in bone?
Osteoclast and Osteoblasts
This hormone goes to osteoclasts to inhibit bone resorption
Calcitonin
This is the term for not enough calcium. It is most likely caused by primary hyperthyroidism or by malignancy where PTH related protein is produced
Hypocalcemia
- A common age related disease of bone, it is defined as significant reduction in bone mineral density with age. The peak is achieved at 30 years and then declines.
- It is accelerated in women due to…
- Osteoporosis
- Estrogen
- This is the most readily absorbed form of iron
- Non-heme iron is absorbed as
- Iron heme
- Fe2+
- Absorption of iron is increased by…
- The RDA is…
- Iron is transported as Fe3+ by…
- It is stored as Fe3+ and bound to
- Vitamin C
- 10 mg
- Transferrin
- Ferritin, partially hemosiderin
Where is dietary iron absorbed?
Intestine
This mineral is associated with oxygenase enzymes including cytochrome oxidase and superoxide dismutase
Copper
- One of the main roles of copper is the scavenging of _______ and other reactive oxygen species
- It is also required for the cross-linking of…
- Superoxide
- Collagen, it is an essential component of lysyl oxidase
This disease codes for a copper transporting ATP-ase. It occurs in newborns and is charactized by failure to incorporate copper into ceruloplasm in the liver and failure to excrete it from bile, leading to toxic accumulation in liver, kidney, brain and cornea
Wilson’s Disease
Liver cirrhosis, progressive neurological damage, or both occur in early childhood to adulthood. Copper accumulates in the brain and cornea and can be visualized via Kaiser-Fleischer rings in the cornea
Wilson’s Disease