Medical Biochemistry

1. COPPER
ZINC
SELENIUM
By
Dr. M. Anuswaru
1st year postgraduate

2. COPPER
• Copper is an important trace element.
• Human body contains 100mg of copper distributed in
different organs.
• Copper is incorporated into several metalloenzymes
and proteins which perform important metabolic
functions.

4. Poor source of
copper

7. Biochemical functions

10. Copper is essential for synthesis of melanin and
phospholipid

13. ABSORPTION
• 10% of dietary copper is absorbed.
• Absorption takes place mainly in duodenum.
ZINC
PHYTATE
MOLYBDENUM
METALLOTHIONEIN

14. EXCRETION
• Excretion is mainly through bile.

15. PLASMA COPPER

16. Copper deficiency
• Severe deficiency of copper leads to demineralization
of bones, demyelination of neural tissue.
• Copper deficiency Anemia : As copper is an integral
part of ALA synthase, its deficiency leads to decreased
heme synthesis.
• Weakening of vessel walls leading to aneurysm

17. Menke’s disease
It is a x-linked disease. Affects mainly male child.
Dietary copper is absorbed but not transported to blood due to
absence of copper binding ATPase. Copper gets accumulated in cells.
Symptoms – depigmentation of hair. Hence called Menke’s kinky hair
syndrome. Decreased copper in plasma and urine.

18. WILSON’S DISEASE
Hepato lenticular degeneration is seen
It is caused by defect in gene encoding a copper
binding ATPase which is required for normal excretion
of copper from liver cells.
Due to this copper is accumulated in liver and lenticular
nucleus of brain
Low levels of copper and ceruloplasmin in plasma with
increased excretion of copper in urine.

19. • Sign of Wilson’s disease- kF ring
TREATMENT
• Pencillamine – naturally occurring chelating agent

20. Copper toxicity
Chronic toxicity is manifested as diarrhea and blue
green discoloration of saliva.
Copper poisoning may lead to heamolysis, proteinuria
and renal failure.

21. ZINC
• Total Zinc content of body is 2grams. 60% - skeletal
muscles and 30% in bones.
• Highest concentration of zinc is seen in hippocampus
area of brain and prostatic secretion.
• Zinc is usually an intracellular element.

23. RDA of ZINC
ADULTS – 10-15mg/day
IN PREGNANCY & LACTATION – doubles

24. BIOCHEMICAL FUNCTIONS
1. Essential component of enzymes like
carbonic anhydrase
Alcoholic dehydrogenase
Alkaline phosphatase
Superoxide dismutase

25. 2. AS Zn is a component of enzyme of superoxide
dismutase which acts against free radical damage. It is
considered as ANTI OXIDANT.
3. Zn stabilises the insulin hormone molecule. Hence it
is present in association with insulin in beta cells but
not in circulation.

26. 4. Zn promotes the synthesis of retinol binding protein.
So it is necessary to maintain the levels of vitamin A in
serum.
5. Zn is required for wound healing and proper
reproduction.
6. Gusten – Zn containing protein in saliva helps in taste
sensation.

27. ABSORPTION – mainly in duodenum
AMINO ACIDS
Copper
Iron
calcium

28. DEFICIENCY MANIFESTATIONS
• Poor wound healing
• Impaired spermatogenesis
• Hyperkeratosis
• Neuro psychiatric manifestations in chronic alcoholism are
partly due to Zn deficiency

29. ACRODERMATITIS ENTEROPATHICA
• Recessive condition
• Absorption is defective

30. Zinc Toxicity
Occupational hazard in WELDERS due to inhalation of
Zn fumes.
Toxic manifestations are seen when intake is more than
1000mg/day.

31. SELENIUM
It is a trace element and anti-oxidant present in soil.
Sources - Liver, Kidney, Sea foods.
RDA is 50 – 100 mg/day

32. Biochemical functions
• Selenium along with vitamin E prevents the
development of hepatic necrosis and muscular
dystrophy.
• It is involved in maintaining integrity of cell
membrane.
• Essential for normal development of spermatozoa.

33. • Se is present in enzyme GLUTATHIONE PEROXIDASE in
the form of SELENOCYSTEINE. This enzyme protects
cells against the damage caused by hydrogen
peroxide.
• Se protects the cell against free radical injury by
preventing lipid peroxidation. Hence an ANTI
OXIDANT

34. • 5’-deiodinase is also a selenium containing enzymes
which converts thyroxine to T3.
• Thioredoxin reductase is also a selenoprotein.
• Se prevents heavy metal toxicity by binding with
them.
• Se protects from carcinogenic chemicals.

35. Deficiency
If the soil is deficient of selenium it causes a condition
called as KESHAN DISEASE
It is characterised by Cardiac Myopathy

36. TOXICITY
SELENOSIS – hair loss, diarrhoea, weight loss,
garlic odour caused by dimethyl selenide.
Selenium is present in metal polishes and anti rust
compounds.

37. THANK YOU