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Flashcards in Cofactors Deck (30):
1

Calcium and Phosphates

Deposited in bones, phosphorus follows Ca

2

Two forms of calcium

1. Calcium phosphate in bones and teeth
2. Free calcium: rqrs transmembrane transport for neuromusc function, membrane work, signal pathways (calmodulin), and clotting cascade

3

Plasma calcium regulation

1. Low plasma Ca, PTH released from Parathyroid leading to calcium liberation from bone via osteoclasts, increased calcium absorption in gut, and increased renal calcium resorption

2. High plasma calcium: calcitonin released from thyroid leading to calcium deposition in bone via osteoblasts and decreased renal resorption

4

Sodium

plays role in blood pressure regulation, water follows sodium

5

Potassium

Action potentials

6

Chlorine

Digestion (HCL) macrophage killing (HOCl) ridding body of CO2 (Cl/bicarb exchange)

7

Iron

Important in redox reactions (ex = cytochrome oxidase), very toxic in free state as it binds to proteins and disrupts function and structure. Most bound to hemoglobin

8

Ferritin

Intracell Iron storage prevalent when iron stores are low, unbound = apoferritin

9

Hemosiderin

Intracell iron storage, prevalent when iron stores are high

10

Transferrin

extracell/ plasma transport. Receptors on intestinal membrane bind iron-transferrin complex and is exocytosed and dissolved to Fe-3 and transferrin. Fe-3 is reduced to Fe-2 by duodenal cytochrome B (ferric reductase, with Vit C). Intracell Fe-2 is transported by DMT1

11

Iron def

anemia, most common nutrient deficiency. Occurs after stores are depleted. Can occur due to hemorrhage. In males this indicates malignancy

12

Hemosiderosis

Fe overload, can induce free radical formation (Fenton) allows for nonpathogenic bacteria to grow (V Vulniferous)

13

Hemochromatosis

Progressive hemosiderosis, can be genetic, damages body. Found in alcoholics due to increased iron absorb, potentially lethal

14

Copper

Important in redox reactions (ascorbic acid oxidase and tyrosinase). Functions in many metalloenzymes. Most bound to ceruloplasmin, rest bound with albumin or complexed with histidine. Elevated in hyperglycemia.

15

Def Copper

Menk's disease = kinky hair syndrome. Copper based enzymes don't function and is fatal

16

Cu Toxicity

Wilsons Disease is a defect in copper transporters besides ceruloplasmin which is increased. Biliary excretion is blocked leading to liver and brain damage

17

Zinc

Important in binding NAD (alchohol dehydratase). Functions in many metalloenzymes and transported via albumin. Stored via metallothionein (also stores cadmium and arsenic) synth increased by heavy metals and protects the cell from their toxic effects

18

Zinc Def

Wernecke Korsakoff Syndrome (alchs)
Zn and Vit B1 def leading to poor growth, aerodermatitis enteropathica = hair loss and diarrhea

19

Manganese

acts as electron sink (histidine ammonia lyase, mitchondrial superoxide dismutase). Often replaced by Mg due to easy access from plants

20

Magnesium

Useful for ATP binding, excreted via kidneys

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Cobalt

Part of cobalamine coenzyme (vit B12) and is in only two enzymes:
methymalonyl CoA mutase and homocysteine methyl transferase

22

Nickel

Catalytic site for urease

23

Molybdenum

Important for redox reactions (Xanthine oxidase)

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Vanadium

Redox rxns (nitrate reductase)

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Selenium

Important in ROS and Hydrogen peroxide detox (glutathione peroxidase). Used to make selenocysteine (-SH) in glut peroxidase. Low in ohio, indicated in CVD

26

Se Def

Keshan Disease = enlarged heart and associated cardiomyopathy, impaired ROS defense

27

Lead

very toxic, interferes with divalent cations, accum = plubism

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Chromium

Role in glucose tolerance factors, Facilitates sensitivity to insulin, indicated in type 1 DM

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Fluorine

Strengthens teeth and bones

30

UV

UVB necessary for Vit D synth, cancer