MANGANESE METABOLISM

2. Manganese Metabolism
Gandham.Rajeev

3. • Total body content of manganese is 15 mg
• It is mainly present in the liver & kidney.
• Magnesium is mainly found in nuclei in
association with nucleic acids.
• It is associated with connective and bony
tissue, growth and reproductive functions and
carbohydrate and lipid metabolism.

4. • Sources:
• Liver & kidneys are rich sources and whole
grain cereals, vegetables and nuts.
• Tea is a rich source of manganese.
• RDA: 2.5 to 5 mg/day.
• Serum manganese:
• Manganese in serum is bound to a specific
carrier protein-transmagnanin.
• Blood contains about 5-20 mg/dl.

5. Absorption
• Dietary manganese is absorbed from the
small intestine.
• Most of the manganese is excreted rapidly in
the bile and pancreatic secretion in the
faeces.
• Ca, P & iron have been found to reduce
manganese absorption.

6. Functions:
• Role in enzyme action:
• Acts as a ‘cofactor’ or as an activator of many
enzymes like arginase, isocitrate
dehydrogenase (ICD), cholinesterase,
lipoprotein lipase, enolase, leucineamino
peptidase in intestine, & 5-oxo-prolinase of
kidneys, small intestine.

7. • Manganese and magnesium may replace one
another in case of some of the enzymes.
• Mitochondrial form of superoxide dismutase
contains Mn++ in its prosthetic group unlike the
cytosol form of the enzyme which contain Cu &
Zn.
• Manganese also function with vitamin K in the
formation of prothrombin.

8. • Role in bone formation:
• Manganese necessary for synthesis or
deposition of mucopolysaccharides (MPS) in
the cartilaginous matrices of long bones.
• Role in fat metabolism:
• Manganese is necessary for hemoglobin
synthesis.
• It stimulates fatty acids, cholesterol synthesis &
it inhibits lipid peroxidation.

9. • Role in carbohydrate metabolism:
• Manganese influences carbohydrate
metabolism by affecting the peripheral
utilization & their conversion to MPS.
• It also participates in glycoprotein &
proteoglycan synthesis.

10. Deficiency
• Manganese deficiency is not seen in humans.
• Manganese deficiencies have been produced
experimentally in animals
• Symptoms:
• Retarded growth, bone deformities & sterility.
• Accumulation of fat in liver.
• Increased ALP levels.
• Decreased activity of beta-cells of pancreas.

11. Reference books
• Text book of Biochemistry - U Satyanarayana
• Text book of Biochemistry – DM Vasudevan
• Text book of Biochemistry - MN Chatterjea

12. Thank You