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Spring M Dahl, MS, PhD
Prepared by: Jeanette Andrade
MS,RD,LDN,CDE
Kaplan University
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What are we going to be learning about
tonight?
Electrolytes: Sodium, Potassium
 Bone Minerals: Calcium, Phosphorus, Magnesium
 Antioxidants: Iron, Zinc, Selenium
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Electrolytes: substances that become ions in solution and
acquire the capacity to conduct electricity
Cation: positive charged ion
Anion: negative charged ion
Hydroxyapatite: calcium phosphate salt
Antioxidant: Reduces oxidative damage such caused by
free radicals
Reactive Oxygen Species: molecules and ions of oxygen
that have an unpaired electron
Zinc Finger Motif: sequence of approximately 30 amino
acids, forming a helix-turn-helix, believed to form a
structure that includes tetrahedrally coordinated zinc (II)
ions
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Major positive cation in fluid outside of the cells
Regulates total amount of water in the body
Transmission of sodium in and out of cells
regulates brain, nervous system and muscles
functions
Normal blood sodium level is 135-145 mEq/L
What can happen if there is too much sodium in
the cells or too little?
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Major cation found inside cells
The proper amount of potassium is essential
for regulation of heart rate and muscle function
Normal lab values are 3.5-5.0 mEq/L
What happens if there is too little potassium or
too much potassium in cells?
Not really a cycle, this diagram is depicting active transport of molecules across a
membrane. Active transport is coupled to ATP hydrolysis to obtain enough
energy to transport ions against their concentration gradient.
outside
Plasma
membrane
inside
NEED ACTIVE TRANSPORT TO PUMP AGAINST A GRADIENT
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Accounts for 1-2% of adult human body
weight
Body stores 99% of calcium in bones and
teeth
It is needed to contract and expand muscles
and blood vessels
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RDA: 19-70 year old males need 1000-1200 mg
of calcium per day
RDA: 19-70 year old non-pregnant/lactating
females need 1000-1200 mg of calcium per day
What foods tend to have calcium in them?
TOXICITY
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Not from high intake of
calcium from foods, but
from supplementsKidney stones occur
from an increased
calcium excretion from
kidneys
DEFICIENCY
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Abnormal parathyroid
function and rarely due to
low dietary intake since
calcium is a large
reservoir in bones
Chronic kidney disease,
vitamin D deficiency, low
magnesium in blood
Chronically low dietary
calcium intake may
prevent peak bone mass
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Majority of phosphorous is found as phosphate
within the body
85% of phosphorous is found within the bone
Major structural component of bone in the form
of hydroxyapatite
What else is phosphorus important for within our
bodies?
RDA for males and females 19-70 year old 700
mg/day
What foods contain phosphorous?
TOXICITY
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Calcification of nonskeletal tissues- most
commonly the kidneys
DEFICIENCY
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Loss of appetite,
anemia, muscle
weakness, bone pain,
rickets, osteomalacia,
and can possibly lead to
death
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60% is within the skeletal structure, 27% within
the muscles, 6-7% within the cells and 1%
outside of cells
Magnesium is required for ATP synthesizing
protein in the mitochrondrion
What other important processes is Magnesium
important for?
What foods contain Magnesium?
RDA for males 31-70 years old: 420 mg/day
RDA for females 31-70 years old: 320 mg/day
TOXICITY
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Not with foods, but
with salts- magnesium
salt
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DEFICIENCY
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Main problem diarrhea
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Rare due to kidneys are
able to reduce urinary
excretion when intake is
low
Occur with
gastrointestinal
disturbances, renal
disorders, chronic
alcoholism, age
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Oxygen transport and storage
Electron transport and energy metabolism
Antioxidant: why?
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Catalase and peroxidase are heme containing
enzymes that protect cells against an accumulation
of harmful hydrogen peroxide (ROS)
White blood cells engulf bacteria and expose them to
ROS in order to kill them
We produce or own disinfectant (clorox)
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What foods contain Iron?
RDA for males 19-70 years old: 8 mg/day
RDA for females:
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19-49 years old: 18 mg/day
50-70 years old: 8 mg/day
TOXICITY
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Accidental overdose
with iron containing
products
Genetic disorders
usually are the cause
 Hereditary
Hemochromotosis
 Hereditary anemias
DEFICIENCY
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Most common
deficiency in the world,
3 levels of iron
deficiency
 Storage iron
depletion
 Early functional iron
deficiency
 Iron deficiency
anemia
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Zinc functions in the cell can be divided into 3 categories:
 Catalytic: enzymes depend on Zinc for reactions
 Structural: for proteins and cell membranes; Zinc
finger motif
 Regulatory: Zinc finger motif regulates gene
expression by acting as transcription factors
Antioxidant: Why?
 Some studies suggest that Zinc is a protective factor
against atherosclerosis by inhibiting the oxidation of
LDL by cells or transition metals (copper, iron)
– Protect cells against Tumor Necrosis Factor induced cell
injury
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What foods contain Zinc?
RDA for males 19-70 years old: 11 mg/day
RDA for females 19-70 years old: 8 mg/day
TOXICITY
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Occurs from
consumption of food or
beverages that have
been contaminated with
zinc released from
galvanized containers
DEFICIENCY
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Severe: generally from a
genetic disorder
Mild: generally children
from developing
countries, however
occurs in pregnant,
anorexics, aging
individuals, celiac
disease and irritable
bowel disease
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Selenoproteins:
Glutathione peroxidases
 Thioredoxin reductase
 Iodothyronine deiodinases
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Antioxidant: Why?
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Glutathione peroxidase- antioxidant enzymes that reduce ROS
by coupling their reduction to the oxidation of glutathione
– Thioredoxin- Thioredoxin reductase participates in the
regeneration of several antioxidants
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What foods contain Selenium?
RDA for males and females 19-70 years old:
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55 uG/day
TOXICITY
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Accidental or suicidal
ingestion of grams of
selenium
DEFICIENCY
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Decreased activity of
glutathione peroxidase,
thioredoxin reductase and
thyroid deiodinases
Chronically ill patients
receiving total parenteral
nutrition (TPN)
Treating metabolic
disorders such as
phenylketonuria (PKU)
NADH ASCR
reductase
Example of antioxidant control
systems of oxidative stress in cells
Exogenous radical-X
Vit C
O2
Vit C
Extracellular Space
Vit E
Vit E
LOOH
O
CoQ10
Plasma
Membrane
PLA2
CoQ10
LOOH
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Minerals/metals
Fe
Se
NAD(P)H+H
GSH- Se Px
Other
Coenzyme Q
Lipoic acid
GSH reductase
GSSG
NAD(P)+
+
Vitamins
Niacin
Vitamin E
Vitamin C
Cytosol
2 GSH
Cyt-b5reductase
or NQO1
Endogenous radical-X
NADPH
NADP+
LOH
G-6-PDH
Detoxification
Glucose-6P
6-P-gluconate
Burgess, J. R. and J. E. Andrade (2006). Antioxidant Effects of Citrus Flavonoid Consumption. Potential Health Benefits of Citrus. B. S. Patil, E. G. Miller, N. D. Turner and J.
S. Brodbelt. Washington, DC, An American Chemical Society Publication.
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How do minerals play into the “big”
biochemistry picture?
Are supplements needed by the average
consumer?
Your “take-away” message?
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How do you feel about this course now that we
are at the end?
Do you see application of this material as you
advance your education and consider your
professional goals?
Overall thoughts on the course?