All trace minerals Flashcards
Where does copper absorption occur?
Small intestine (location of absorption was not specified for other trace minerals)
What increases copper absorption?
acidic milieu (milieu=environment)
- I got you
(acidic environment also increases absorption of non-heme iron)
What decreases copper absorption?
Calcium, phytates, fiber and zinc (again, also decreases absorption of non-heme iron)
How is copper transported from intestine to tissues?
Bound to ALBUMIN (same as zinc except zinc can also bind to transferrin)
How is copper transported from liver to tissues?
Bound to CERULOPLASMIN
Functions of Copper?
involved with collagen, ROS, neurotransmitters and iron recycling
(1) component of lysly oxidase (important for elastin and collagen)
(2) cofactor for superoxide dismutase (removes reactive oxygen species)
(3) cofactor for monoamine oxidase system (involved in the synthesis of neurotransmitters)
(Note: iron is also important in synthesis of neurotransmitters)
(4) when bound to ceruloplasmin (basal membrane of mucosal cell), promotes iron transportation (note: ceruloplasmin also transports copper from liver to tissues)
What is ceruloplasmin?
Major copper-containing protein in plasma, calcium transporter, involved in iron absorption and iron recycling from macrophages
Why is ceruloplasmin important?
For recycling of iron in macrophages (from RBCs to circulation)
** Further explained ** RBCs age (called senescent erythrocyte). These aged RBCs can be phagocytosed by macrophages. Ceruloplasmin retrieves the ferrious iron in the macrophage after it “eats” the aged RBC. Retrieves ferrious iron and then converts it to ferric iron so it can bind to transferrin
Symptoms from a copper deficiency?
anemia, connective tissue damage (affects hair and skin growth), excessive bleeding (copper is important for clotting)
What is the syndrome resulting from a copper deficiency?
Menkes syndrome (genetic syndrome but can be see in malnourished children)
Symptoms of copper toxicitiy?
Abdominal pain, nausea, vomiting and diarrhea
Disease resulting from copper toxicity?
Wilson disease (Remember the copper related diseases start with M/W -> flip letter upside down - wombo mode)
What is wilson disease?
copper deposits in the brain, kidney, corna and liver with low blood copper levels
What is the concern with acidic beverages and copper containers?
Acidic beverages in containers made with copper. Increases the amount of copper absorption.
Treatment for copper toxicity?
(1) zinc toxicity
(2) penicillamine
Sources of Selenium?
Brazil nut, seafood, meats, nuts, grains (content of food varies depending on the selenium content of soil)
Biologically active form of selenium?
selenocysteine
Storage pool form of selenium?
selenomethionine
Describe absorption of selenium
efficient, not regulated
Where are the highest concentrations of selenium found?
liver, pancreas, muscle, kidneys and thyroid
Functions of selenium?
- antioxidant enzymes, thyroid enzymes (necessary for 5’ deiodinase which converts T4 to T3), immune enzymes
component of 25 proteins, part of the antioxidant enzymes essential for normal thyroid function, essential for normal imune function
What are some of the antioxidant enzymes that selenium is a part of?
glutathione peroxidase, thioridexin reductase, selenoprotein P
Describe the connection between selenium and vitamin E.
Selenium works in concert with vitamin E to prevents lipid peroxidation and cell membrane damage
What does glutathione peroxidase do?
Glutathione peroxidase, along with selenium, converts hydrogen peroxide to water (reduction reaction)
Who may have a selenium deficiency?
(1) patients on total parenteral nutrition (Parenteral nutrition, also known as intravenous feeding, is a method of getting nutrition into the body through the veins.) (This also applies to zinc deficiency - total parenteral nutrition before 1971 - no zinc was added)
(2) people with gastrointestinal problems
What is keshan disease?
Selenium deficiency with complications resulting in poor cardiac function and an enlarged heart
Symptoms from a selenium toxicity?
GI upset, joint pain, hair loss, nail discoloration, fatigue
Toxicity in selenium - How?
industrial accidents or supplementation
Major source of fluoride?
fluoridated water, tea, seafood, seaweed (also toothpaste)
Does fluoride have a metabolic function?
No known metabolic function
Then, if it has no metabolic function, why is fluoride important?
increases tooth mineralization and bone density, reduces development of dental caries (dental caries=tooth decay; due to activities by bacteria), promote enamel re-mineralization (hydroxlylapatite vs fluorapaptite)
What should be known about fluorapatite?
The presene of fluoride converts hydroylapatite to fluprapatite
What is fluorosis?
a chronic condition caused by excessive intake of fluorine compounds, marked by mottling of the teeth, discoloration of teeth and pitting of the enamel