Vitamins Flashcards
Vitamin Deficiencies
result from inadequate supply
Vitamin Insufficiencies or vitamin Dependencies result from
result from abnormal
metabolism with an adequate supply
Vitamin toxicity ( Fat soluble) can result if
can result if over-ingested
Vitamins physiological functions
- Serve primarily as cofactors of enzymatic
reactions in body - Some function as hormones (Vit A & D)
- Some function as transcription regulators (Vit A)
** Must be obtained from external sources
Vitamins that serve as transcription factors
Vitamin A
Vitamins that serve as hormones
Vit A and D
Vitamins metabolism
1.Reduced serum levels may not indicate a
deficiency that interrupts cellular function
2.Normal values may not reflect adequate function
2A) Clinical expression of Vit abnormalities
2B) Clinical symptoms of Vit deficiencies: nonspecific
in early as well as in mild chronic stages
➡ Deficiencies difficult to diagnose initially
Fat soluble vitamins
A, E, D, K
Water soluble vitamins
B vitamins: thiamine, riboflavin,
niacin, B6, B12,
folate, pyridoxine,
pantothenic acid &
others
➢Biotin
➢Vitamin C
➢Carnitine
Laboratory measurements of vitamins
➢ vitamin precursors
➢ vitamin
➢ vitamin metabolites
➢ some biochemical function with and
without vitamin (Schilling, etc.)
Blood (serum/plasma) or urine
* Immunoassay, HPLC, CPB
- RIA, MEIA, and FPIA
Immunoassays of vitamins
HPLC, CPB
RIA, MEIA, FPIA
FAT soluble vitamins
types
Absorbed as part of
what must be present for Absorption
what conditions are they deficient
-A,D,E,K
-Absorbed as part of the chylomicron
* Fat must be present for absorption
* Chronic malabsorptive states
Fat soluble Vitamins come from what sources and where are they stored
Dietary sources
animal & plant products—varies with
vitamin
Stored in liver and fat tissue
Deficiencies of fat soluble vitamins
Vitamin A, E, and D+K storage
May be difficult to
Deficiencies: develop slowly
- Vit A storage: 1 year
- Vit E storage: several months
- Vit D & K: storage days or weeks
may be difficult to diagnose; vague symptoms
Fat soluble vitamins disorders
Bile and pancreatic function,
bowel mucosa
mpaired bile flow,
* Pancreatic disease
* Chronic bowel inflammatory conditions
* Fistula
* Small bowel obstruction
* Alcohol liver disease
* Cryptosporidium infection
New acquired form of lipid soluble vit deficiency
- A,D,E,K
✴ Lipase inhibitor: Xenical
✴ Ingestion of non-bioavailable fat substitutes: Olester
✴ Patient after bilopancreatic diversion for obesity
Water soluble vitamins
At least how many water soluble vitamins
Moderate excess intake is
Most are stored for
Deficiencies develop more rapid then
- At least 9 water soluble vitamins
- Moderate excess intake is almost immediately excreted in the urine
- Most are stored for <2 months
➢Deficiencies develop more rapidly than fat soluble vitamin
deficiencies
Exceptions is vitamin
-B-12
-can be stored in the liver for up to 12 months.
Vitamin A
has how many active forms and what are there names
* Derived from dietary carotenoids (β-carotene)
Three biologically active forms
➢Retinol, Retinal, Retinoic acid
Vitamin A dietary source
➢animal and plant
➢butter, al-livcream, whole milk, whole milk
cheeses, egg yolk
➢dark green leafy vegetables, yellow vegetables,
yellow fruit & fortified margarine
Retinol is carried by
Chylomicrons in the lymphatics to the liver where retinol binds to RBP and pre-Albumin
Retinol + RBP/ Pre-albumin attaches to RBP-receptor and allows Retinol + cRBP into the cell.
Functions of vitamin A
➢Vision (most clearly defined role)
➢Growth
➢Reproduction
➢Mucus secretion
➢Immune system functions
➢Epithelial cell development, differentiation,
regulation.
Vitamin E: Tocopherol has several isomers but
a form is most studied
Vitamin E: Tocopherol dietary sources
➢Vegetables oils
➢Wheat germ, rice germ,
➢Leafy green vegetables,
➢Legumes & nuts
* Transported: w/ chylomicrons &
VLDL (aTTP)
* Stored primarily in adipose tissue
Vitamin E: Tocopherol functions
➢Antioxidant
➢Protects cell membrane (RBC) from
oxidation of lipids in the membrane.
➢Therapeutically to prevent hemolytic
anemia. (premature newborns)
➢Anti-aging, cardio and neuro protection
Vitamin K: hydroquinone
has several structures and they are
K1, K2, K3
Vitamin K Dietary sources
➢cabbage, cauliflower, green leaves of
alfalfa, spinach, liver, soy beans and
vegetable oil.
➢Intestinal bacteria
–> 50% from each source
*Absorption is with chylomicrons
Vitamin K (hydroquinone) functions
- Normal coagulation
➢Required for synthesis of Factor II, VII, IX,
X, protein C & S
✓Acts as a cofactor in Vit-K dependent
carboxylation of glutamic acid
Vitamin K1 is
Phylloquinone
Vitamin K2
Menaquinone-4
Vitamin K3
Menadione
Two forms of Vit D
Vitamin D3= cholecalciferol
Vitamin D2= Calciferol
Vitamin D3
➢Produced in skin from UV
activation of 7-dehydrocholesterol
➢Prohormone converted by liver to calcidiol
à hydroxylated to calcitriol (active form
Vitamin D2
*Vit D 2 : calciferol (dietary form)
➢Hydroxylated to calcitriol in the same way as D
Dietary sources of Vitamin D
➢Fish liver oil
➢Fortified milk
➢Irradiated foods
( Ionizing Radiation)
➢Smaller amounts in butter, egg yolk, liver, certain fish (esp. salmon and sardin
Vitamin D functions
➢Calcitriol enhances Ca2+ uptake from the GI and increases the release of Ca2+ from
bone into blood
Vitamin A deficiency lead to
Decreased vision and Decreased Immune system function
Vitamin A toxicity
—> upon what
symptoms
Upon overdose
❑ Symptoms:
* Dermatologic disorders
* Bone pain
* Renal disorders
* Intracranial
hypertension
* Hemorrhage
* Teratogen
Total Vitamin A assay
Retinol(RBP) assay
B-Carotene
- Total Vit A:
➡Fluorometry or HPLC - Retinol (RBP):
➡Immunoassay - β-Carotene:
➡Extraction of β-carotene, - measure directly @ 450 nm
** Light sensitive
Vitamin E Deficiency
- Rare
- Neurological signs
- Ataxia
- Peripheral neuropathy - Macrocytic megaloblastic Anemia
Vitamin E Assay
- HPLC
- GC-IDMS
- Photometry or Fluorimetry
- TLCG
à separate tocopherols &
tocotrienols.
Vitamin E assay reaction
Tocopherol + FeCl3
—–> Tocopheryl quinine + Fe2+ + a,a-dipyridyl [ Red].
Vitamin K deficiency
- ~ 3 weeks to develop
- Hemorrhage secondary to reduced
prothrombin and other coagulation factors - ecchymoses, epitaxis, intestinal
hemorrhage
Vitamin K Assay
- Seldom measured directly
- PT & APTT
à Both will be prolonged in a deficiency,
but thrombin time will be normal - Direct measurement:
immunoassay or HPLC (rare)
Vitamin D deficiency
- bone malformations
–> à Rickets in children and osteomalacia in adults
Vitamin D Assays
- Immunoassay
- HPLC
- LC with Mass Spec (LCMS)
** Normal values still being debated - <50 nmol/L considered low
water soluble vitamins
Vitamin C and B
Vitamin C
-Distributed throughout what
- Deficiency may take several blank to
- High concentrations in
- Excreted in urine as blank
- Distributed throughout tissues
- Deficiency may take several months to develop symptoms
- High concentration in CSF
- Excreted in urine as oxalate
Plasma Vitamin C concentration is lower then
CSF
Oxalate is the metabolite of
Oxalate is the metabolite of Vitamin C –~50% of urinary oxalate is from
Vitamin C
Ascorbic Acid dietary sources
-Found primarily in citrus fruits & vegetables: oranges, lemons, limes,
tomatoes, grapefruit
- Other vegetables and fruits: green peppers, broccoli, leafy green vegetables, potatoes,
strawberries
-Heat and oxygen labile
Vitamin C is high in what foods
found primarily in citrus fruits & vegetables: oranges, lemons, limes,
tomatoes, grapefruit
Highest in those foods when they are fresh & uncooked
Many plants and animals can synthesize what but humans cant
Plants and many other animals can synthesize Vitamin C, but humans cannot—
must be ingested.
Protein and glucose ?
Vitamin C- Functions
- Functions as an electron transfer molecule for enzymes involved in
collagen formation and stabilization - Antioxidant
- Involved in catecholamine synthesis
- Cholesterol metabolism
- Synthesis: Carnitine, Steroid
- Uptake of non-heme iron
Vitamin C function in Collagen and formation and stabilization
via hydroxylation of proline & lysine which are required to allow the formation of the triple helix and
the cross linking of the collagen chains). (Most well-described function and clinically demonstrated
in the Scurvy which is a disease of impaired cllagen synthesi
Vitamin C roll in Catecholamine synthesis and what type of vitamin C is involved
tyrosine conversion to the catecholamines
via dopamine β-hydroxylase. Adrenal
(medulla) have much higher concentration
of Vit C
Vitamin C involvement in Uptake of non-heme iron
in the gut is facilitated by asobic acid through the
nonenzymatic reduction of Fe 3+ to Fe2+
Vitamin C- Deficiency
It may take how many months to develop
Vitamin C is distributed throughout tissues, a deficiency may take several months to exhibit
symptoms.
Vitamin C deficiency can result in
Deficiency results in SCURVY
Impaired collagen synthesis
Breakdown of connective tissues
-Gum and tooth
disease
-Bone disease
-Poor wound healing
Vitamin C symptoms
- weakness, irritability, pains in joints/muscles
- Bleeding into skin, GI tract & urinary tract
Vitamin C plasma value
less then 13 micro meters
Vitamin C assays
- HPLC is currently the predominant laboratory method.
- Both serum & leukocyte assays available
What vitamin C assay is the best
Leukocyte assay is probably Best
Because of limited stability of ascorbic acid in plasma and serum (better in whole blood).
After only 1 day at room temp, serum ascorbic acid measurements are significantly
diminished and are undetectable by the day 2. Similarly, serum stored at 4 ºC shows
significant decreases in ascorbic acid levels after 3-5 days.
—> serum and plasma measurements do not correlate very well with tissue vitamin C
levels.
Vitamin C
what levels vary
- Serum levels vary
- There is an inter laboratory variability with an average CV of 15% across multiple studies. This
variability is most likely related to differences in the differential detection of the many ascorbic
acid isomers/metabolites
Vitamin C amount associated with scurvy
less then 0.24 mg/dl associated with scurvy
greater them 0.14 mg/dl will be cleared by the kidneys
Vitamin B2
what the name
is what color vitamin
what are activators
Riboflavin
- Yellow-pigmented vitamin
- FMN, FAD + are activators
Vitamin B2 functions
– Serves as a cofactor in a variety of oxidative reactions:
Fatty acid oxidation
TCA cycle reactions
Oxidative phosphorylation in the respiratory chain
– Important in metabolism of iron, pyridoxine, and folic acid
– May help protect from oxidants
Vitamin B2 Dietary Sources
➢ Found in milk
➢ Organ meats, such as liver
➢ Other meats,
➢ Leafy green vegetables
Riboflavin deficiencies result in
Dermatologic changes
Mouth lesions
Glossitis (smooth tongue)
Eyelid spasms & conjunctival congestions
Hematologic dyscrasias
Riboflavins better measurement
- Measurement of RBC riboflavins & flavins
- (FMN, FAD) are better than serum
Riboflavin and its two cofactor active forms are
Riboflavin and its two cofactor-active forms riboflavin 5’ phosphate mononucleotide (FMN) and
flavin adenine dinucleotide (FAD +) (ßthe most water soluble) exhibit fluorescence.
* FAD + is orange fluorescence;
* Riboflavin & Riboflavin 5’ phsophate fluoresce yellow-gre
Riboflavin has what activity in RBCs
- Glutathione reductase activity (coefficient) in RBC (EGRAC)
Pyridoxine
Group of compounds are structurally related to
Group of compounds structurally related to pyridoxal phosphate (P5P, PLP)
Riboflavin is what number of B vitamin
Vitamin B2
Functions of Pyridoxine
- Important co-factors for catalysts in transamination (transferase) and
decarboxylation of amino acids - Active in > 60 enzyme systems
Pyridoxine Dietary sources
-Primarily in meat, poultry, fish
-Also in sweet potatoes
-Other vegetables
Best known function of the pyridoxine cofactors are
Best known functions of the pyridoxine cofactors
are their roles in the conversion of tryptophan
to serotonin, tryptophan to nicotinic acid and
metabolites (niacin)
Pyridoxine deficiencies
symptoms are
- Weakness
- Abdominal pain, vomiting
- Seizures
Pyridoxine: Deficiencies
Conditions associated with deficiencies include
-Alcoholism
-Pregnancy
-Certain drug therapies: Ca ++ channel blockers, oral contraceptives,
isoniazid, steroids, penicillamine
Pyridoxine: Deficiencies
Measurements is usually by what
HPLC
Niacin ( nicotinic acid)
Function
Coenzyme
The active cofactor forms: collectively called the ‘pyridine nucleotides’
Niacin is a component of the coenzymes NAD+ & NADP+
NAD + & NADP+: involved in oxidation-reduction reactions
Example: glutamate dehydrogenase, LDH & G6PDH
Pyridoxine is what B vitamin
vitamin B6
Niacin( Nicotinic acids) are involved in what type of reactions
NAD + & NADP+: involved in oxidation-reduction reactions
Example: glutamate dehydrogenase, LDH & G6PDH
Niacin (nicotinic acid) Dietary source
-Meats, poultry, fish
-Grains (except corn), esp. whole grains
-Flours, cereals
-Nuts, legumes
-Anything rich in tryptophane is typically a good source of niacin
–NAD + & NADP+ can also be synthesized from liver tryptophane
NAD and NADP can also be synthesized from
The liver
-Anything rich in tryptophane is typically a good source of
Niacin
Niacin Deficiency
causes what condition
Early symption
- Niacin deficiency causes a condition called “pellagra”
- Early symptoms include lethargy, anorexia, weakness, digestive disturbances,
weight loss, dermatitis
Niacin - Deficiency
Late symptoms
and Pellagra is characterized by
- Late symptoms include mucus membrane inflammation
à Result in diarrhea, urethritis and vaginitis
à Mental disturbances with disorientation
** Pellagra is sometimes hallmarked by the ‘3 D’s—Diarrhea, Dermatitis, Dementia
Niacin Toxicity
- Symptoms of toxicity include:
Cutaneous flushing, gastric irritation, liver dysfunction with jaundice, hyper uricemia,
impaired glucose tolerance - Niacin is sometimes prescribed in high doses to treat elevated LDL cholesterol
Niacin is what number of B vitamin
Vitamin B3
Thiamine function and number of B vitamin
B1
- Function:
–As thiamine pyrophosphate, it is a cofactor in enzymatic decarboxylation of
ketoacids in the formation of ketols
–Major carbohydrate pathways
–Metabolism of branched chain amino acid
How does Thiamine function in the Carbohydrate pathway
Pyr—> Acetyl CoA
Thiamine Dietary sources
–Yeast, wheat, whole grain and enriched breads, cereals
* Highly water soluble & easily leached from foodstuffs during washing or
boiling
Thiamine deficiency
symptoms
Alcoholic & Elderly
- anorexia, alcoholism, vomiting & diarrhea, edema, cardiac failure
—> Mg ++ deficiency(alcoholism): impairs thiamine activation
—-> Associated with poor appetite, fatigues and peripheral neuritis
Thiamine is associated with what type of people
- elderly adults with psychiatric disorders
Thiamine deficiency
what type of therapy
(Loop Diuretic –elderly adults take this sometimes)
Servere Deficiency of Thiamine presents as a what
neuropathy (beriberi)
-Wet [heart & circulatory system]
-Dry [neuronal damage]
–> loss of muscle strength
—> eventually muscle paralysis
Biotin is part of the
Biotin is what sensitive and poorly what
- Biotin is part of the B complex (B7 )
** Biotin is heat sensitive and poorly soluble in water
Biotin acts as
- Acts as a coenzyme in pathways of gluconeogenesis, FA synthesis and AA
metabolism
coenzyme for carboxylation & carboxyl group exchange
enzymes that rely on Biotin
acetyl CoA, propionyl CoA, pyruvate carboxylase, methyl malonyl
oxaloacetic transcarboxylase (Impt as coenzymes in some of these enzyme rxns/activities)
Biotin is inhibited by
Inhibited by raw egg whites in diet (binds to avidin in egg whites)
Biotin dietary sources
Found in many foods, especially liver and other organ meats, kidney, milk, egg yolk,
yeast, nuts, legumes
Biotin deficiencies
✦ Dermatitis
✦ Neurologic changes, mental changes
✦ Nausea & anorexia
✦ Alopecia: autoimmune skin disease
✦ Impaired immunity
✦ Anemia
✦ Peripheral vasoconstriction
✦ Coronary ischemia
Biotin Deficiencies
Autoimmune skin disease that leads to hair loss
Alopecia
Pantothenic acid (B3/B5)
Essential what
Involved in what types of metabolism
- Essential growth factor
- Involved in fatty acid metabolism
Metabolically, pantothenic acid is converted to what
4-p-pantothenine which is bound to coenzyme A
or another acyl carrier protein. CoA complex functions like ”acyl group transfer
enzyme” (COO- )
Pantothenic Acid (B3/B5)
Dietary sources
liver & other organ meats, milk, eggs, fish (especially salmon), peanuts and other
legumes, mushrooms, whole grains
Pantothenic Acid (B3/B5)
what is not known
Pantothenic acid deficiency has been induced experimentally and signs of deficiency include
apathy, depression, increased infections, burning sensations, and muscle weak
Vitamin B12 and Folate
how do they interact and assayed
Vit B 12 and folate interact
metabolically
à a deficiency in either results
in megaloblastic anemia
Vitamin B12 functions
synthesis of
folate
Vitamin B12:
name
is what structure
Cobalamin
Vit B 12 is a tetrapyrrol ring structure with a central cobalt atom
Vitamin B12: Cobalamin
Functions
- Important in hematopoiesis
- Acts as an adenosyl cobalamin (Coenzyme B12),
functions in the formation of CNS myelin sheath - Amino acid synthesis
esp. branched-chain ketoacid metabolism - Folate synthesis
Folate synthesis is required for
Required for synthesis of Purine & Pyrimidine needed for DNA synthesis
Vit B 12 : Cobalamin
Dietary sources
how is vitamin B12 absorbed
Vitamin B12 type one one name
–Meat, eggs, milk
–> Vegetarians are at risk for deficiency
* Vit B 12 absorbed in GI tract after complexing with intrinsic factor (IF)
* Vit B 12 transported in serum by transcobalamins I(cobalophilin), II, III.
Intrinsic factor comes from
gastric parietal cells
Vitamin B12 deficiencies
Result in what symptoms due to what
what types of anemia
- Result in neurologic symptoms due to myelin sheath degeneration
- Megaloblastic anemia due to impaired DNA synthesis, which results from folate
deficiency
hereditary VitB12 is known as
Imerslund Syndrome
Older adults have higher incidence of Vit B12 deficiency due to
prob. due to poor
nutrition/ absorption
Vitamin B12 measurements and Evaluation
Levels measured by immunoassay
* Once deficient confirmed, necessary to determine the cause of Vit B 12
deficiency
à often associated with defects in secretion of intrinsic factor
* Function test: traditional Schilling Test (not performed often
Schillings test is for what and steps
Vitamin B12
1.) The Schilling test evaluates absorption of an oral dose of radioactive B-12 by measurement of urinary excretion of the radiolabeled vitamin.
2.) First–A large injection of B-12 is first administered to bind all B-12 binding sites.
3.) Then the oral radioactive dose of B-12 is administered.
If little radiolabeled vitamin is excreted (<10%), this generally indicates either malabsorption or lack of intrinsic factor.
4.) Wait 3-5 days for all radiolabeled B-12 to clear from body.
5.) Repeat test, but include an oral dose of IF (intrinsic factor) with the radioactive B-12.
6.) If the oral dose of IF causes increased absorption and excretion of the radiolabeled, then it is labeled a true pernicious anemia ( lack of IF).
7.) If it is not corrected it is an intestinal malabsorption problem, such as tropical sprue of D. latum infection
Folic Acid is also known as
pteroylglutamic acid
Folate is necessary for
what is necessary for folate metabolism
-Folate is necessary for normal DNA synthesis
- Vit B 12 is necessary for the metabolism of folate, converting THF to 5’,10’methyl-THF form
required for DNA synthesis
Folic Acid - pteroylglutamic acid
Dietary sources
Primarily found in green leafy vegetables
Fruits
Organ meats
Boiling & use of large amounts of water result in vitamin destruction ( or washing away)
Folic acid Dietary concerns
American diet may be inadequate in folate needs during adolescence, pregnancy and lactation
Rapid depletion may occur with increased need
Growth in adolescence, poor teen diet may result in deficiency
Individuals planning families should wait to have adequate what
Individuals planning families should be sure to have adequate folate for one year prior to pregnancy (some say males, too).
Folate is part of prenatal vitamin supplement
Folate Deficiency results in
Characterized chemically-
Hematological Characteristics-
results in megaloblastic anemia due to abnormal DNA synthesis
* Megaloblastic Anemia:
Characterized chemically by low erythrocyte folate and increased
homocysteine levels
Hematological Characteristics: macroovalocytes, hypersegmented
neutrophils, and megaloblastic marrow
Classic Vitamin B12 assay
-Competitive Protein Binding Assays.
-The intrinsic factor was used as the binder and Co 57 as the radiolabel
Vitamin B12
current assays
competitive binding immunoassay (Ab binder);
some form of FPIA or chemiluminescent IA
Boiling or chemical destruction of endogenous binders is required
For Vitamin B12 use what samples and protect from
Fasting samples
* Must use serum: heparin binds Vit B 12
* Protect from light= Vit B 12 is photolytic
Recent food intake increases what
Vitamin B12 serum
Vitamin B12 storage
4 o C for
24 hours; -20 o C if > 24 hrs
For Classic folate assay use
classic was CPB with β-
lactoglobulin as a binder and I125 as radiolabel
Current method for Folate
-Current is immunoassay with Ab as binder
(FPIA or MEIA)
**Boiling or use of chemical inhibitors required to destroy
endogenous protein binders
or blocking may be used. (Endogenous binders
are albumin & FBP)
Folate assays what samples are used
-Both Serum and RBC hemolysate are used as samples
* Fasting samples
Folate Assay
Storage of serum specimens
4o C for 24 hours; -20 o C if > 24 hrs
Reference values
Serum folate 1.9—14 ng/ml
RBC folate 200—1000 ng/ml
Additional Assays: Vit B12 & Folate
-Serum & urinary methylmalonic acid
Will be increased in Vit B12 deficiency, but normal in folate deficiency
* Homocysteine
Will be increased in both Vit B12 and folate deficiency
Carnitine (Bt)
types
L-carnitine & Acylcarnitines
—> ‘conditionally essential’ nutrient (AA)
Carnitine (Bt)
Dietary resources
Average diets provide
Strict Vegetarian diets provide
Found in meat, poultry, fish and dairy products
Plants contain little, except peanut butter, asparagus and avocados
Average diets provide > half of human requirement; most is absorbed
“Strict vegetarian diets” provide ~10% of requiremen
Carnitine metabolism
requires what for synthesis
where is the synthesis
New synthesis requires N-tri-methyllysine residues of proteins;
–> rate determined by the availability
Synthesis: Liver, Brain, Kidney.
Storage: Muscle
Carnitine: Metabolism
Uptake from gut via
Excreted in
Carnitine Transport Protein
urine (free & esterified form)
Carnitine Function
Facilitates entry of
Facilitates entry of long-chain FA into mitochondria for energy
production
Carnitine: Primary Deficiency
results in
type of genetic disorder
Children symptoms
Rare
* Results in muscle weakness and fatigue
* Usually an “autosomal recessive disorder”
* Children: cardiomyopathy, hypoglycemia, elevated ammonia, muscle
weakness
Administration of large doses of carnitine (temporarily) reverses what
primary carnitine deficiency
Administration of large doses of carnitine (temporarily) reverses
the disorder (which is a result of a mutation of the organic cation
transporter “OCNTN2”
Other causes of primary carnitine deficiency
without cardiomyopathy are not clearly understood and “do
not always respond to carnitine supplements
Carnitine Deficiency, Acquired
- Inadequate intake
- Increased urinary loss
- Pregnancy and breast feeding: éé demand
- Infants, children, and patients on long-term parenteral nutrition
“most vulnerable groups”
Secondary deficienciey results in
Patients on “hemodialysis” may lose
Muscle dysfunction
Patients on “hemodialysis” may lose carnitine in dialysis fluid (not yet
recommended supplementation)
Carnitine: Other
Carnitine therapies are
are sometimes used with disorders of ammonia
metabolism, liver disorders
Valproate is uses to
Valproate [used to treat epilepsy] is associated with liver toxicity: Carnitine
sometimes used in the management of liver injury caused by valproate.
Some studies of Alzheimiers dlsease
L-Acetyl- Carnitine
somewhat beneficial in various trials of HIV-associated neuropathy
Some studies show benefits in treatment with carnitine for diabetes nepthropathy
Vitamin Supplementation
-Vitamin supplementation may sometimes be warranted in nutritional
deficiencies
* No evidence exists to show intakes in excess of what is needed for
general health is useful
* Megadoses of vitamins have not shown to prevent common cold or
cancer or heart disease
