2. Copper metabolism
Human body contains about 100 mg of copper, mostly in bones,
liver, kidneys and muscles
Copper is an essential trace element required in diet because it
is a Co-factor for many enzymes such as superoxide
dismutase, Cytochrome oxidase, tyrosinase, lysyloxidase,
ceruloplasmin
3. Absorption, Storage & Transport
Copper enters the mucosa by a specific transporter Ctr-1within the
cell
Copper is bound to metalothionines in which it is transported and
stored in cells
4. Absorption, Storage & Transport
Copper is efluxed by the enzyme called copper binding P-type
ATPase into the plasma and then is carried to the liver in bound form
with albumin
5. Absorption, Storage & Transport
Each ceruloplasmin molecule bind 5 Cu atoms
Part of copper in the liver is excreted in bile also
In the liver, it is combined to apo-ceruloplasmin to form
ceruloplasmin which is then secreted into plasma
6. Ceruloplasmin
Ceruloplasmin oxidises Fe+2 to Fe+3 which is the form
bound to transferrin in plasma
The major carrier of available for copper in plasma is
albumin to which Cu+2 is loosely bound.
7. Excretion of copper
Major excretion of copper is through bile(1.5-2) mg daily.
Only small amount < 400μg/day excreted in urine.
8. Disorders of copper metabolism
Deposition of Cu++ into
organs like liver, brain,
kidneys and RBCs
Serum ceruloplasmin levels
are decreased.
Wilson’s disease
9. Causes
Wilson’s disease
Wilson’s disease is caused due to mutations in the P-
type ATPase gene.
The mutated protein leads to accumulation of copper in
liver and other organs.
14. Aceroloplasminemia
It is a genetic disorder in which
very low or absent ceruloplasmin
levels are seen in blood
Low ferroxidase activity leads to
the failure of release of iron from
cells leading to iron toxicity
15. Coppper deficiency and Hairs
Tyrosine is a copper containing enzyme. It is needed for
melanin synthesis.
Prolonged copper deficiency aggravates hypopigmentation
and premature graying of hairs.
Alternate black and white patches of hair (flag type) of
hair growth.
16. Fluoride
Fluoride is a major component of teeth enamel where 95% of
total body fluoride (2.5 mg) is present .
17. Function of fluoride
It hardens the hydroxyapatite crystals of calcium phosphate
and thereby makes the bone matrix and enamel
It inhibits the enolase enzyme
18. Source and requirement
Sea food, cheese, milk and
drinking water
RDA : 1-2 mg/day which is
easily met by water which has
0.5-0.8 ppm of fluoride
19. Deficiency - Dental caries
Water should have at least 0.5 parts per million of fluoride to prevent
dental caries
20. Flurosis
Excess of fluoride causes fluorosis which can occur in teeth and bones.
Skeletal fluorosis calcium deposit in tendons and ligaments
21. Zinc
Zinc is needed for the activity of more than 300 enzymes.
Carbonic anhydrase, superoxide dismutase,
carboxypeptidase
DNA and RNA polymerase, Reverse transcriptase
22. Functions of Zinc
DNA binding proteins have zinc finger motifs containing zinc
These are regulatory proteins influencing gene expression
Insulin secretion and storage in β-cells, antioxidant effect of superoxide
dismutase and spermatogenesis are also Zn++ dependent.
23. Absorption
Dietary zinc is absorbed from duodenum
Iron, calcium, copper, cadmium, phytates interfere in Zn++
absorption
30. Zinc toxicity
Rat poisons which contain Zn++
Workers involved in welding due to inhalation of welding fumes
contain ZnO
Manifestations: epigastric pain, gastric ulcer, pancreatitis, diarrhea,
vomiting, nausea
31. Selenium
Total human body content is 5-6 mg
Human body contains selenium as selenocystein in protein
33. Functions of Selenium
Se is part of Co-enzyme Q takes part in electron transport chain
Se is a co-factor for deiodinase which is required conversion of
T4 to T3 active of thyroid hormone
