About Glucosamine

  Glucosamine is a compound found naturally in the body, which is the building block for articular cartilage’s extracellular matrix. Glucosamine is made up from glucose and the amino acid glutamine.

  Glucosamine is part of the structure of the polysaccharides chitosan and chitin, which compose the exoskeletons of crustaceans and other arthropods, cell walls in fungi such as Aspergillus niger and many higher organisms.

Source

  • Present in meat, fish and poultry.
  • The connective tissue of animals, such as chicken marrow, and other animal materials, such as shell fish exoskeletons.
  • Synthesized in the body.
  • Manufactured from chitin, a substance found in shrimp, crab, and lobster shells.
  • Chemically synthesized.

Glucosamine

  There are different forms of glucosamine.

  • Glucosamine sulfate (most common form)
  • Glucosamine hydrochrolide.
  • Glucosamine hydroiodide.
  • N-acetyl Glucosamine.

Biochemistry Of Glucosamine

  Glucosamine is modified glucose with a NH3 group replacing the OH group found on carbon two (C-2). G6-P is an amino monosaccharide (amino sugar) produced in the body by the combination of glutamine with fructose, through the enzymatic action of glucosamine synthetase.The synthesis of G6-P begins with the structural rearrangement of glucose 6-phosphate to fructose 6-phosphate to facilitate interaction with the amino acid glutamine. The enzyme glucosamine synthetase facilitates the transfer of an amide group (NH3) from glutamine to fructose 6-phosphate. The enzyme simultaneously isomerizes this compound to form G6-P (note: isomerization indicates an intramolecular rearrangement of a compound without any net change of the components of the compound). The resulting G6-P molecule is the precursor to all hexosamines and hexosamine derivatives. This first biotransformation of glutamine and fructose 6-phosphate to G6-P is considered the rate limiting step in amino sugar biosynthesis, and is an essential step in the glycosylation of all proteins. G6-P is then acetylated by coenzyme A, resulting in the formation of NAG.

  NAG can subsequently be converted into either N-acetylgalactosamine or N-acetylmannosamine. An additional three carbon atoms can be added to N-acetylmannosamine to form N-acetylneuraminic acid (also called sialic acid). G6-P and its sugar derivatives can then be incorporated into all of the macromolecules requiring amino sugars.

Working Of Glucosamine In Arthritis

  Rheumatoid arthritis (RA) is a chronic and progressive inflammatory disorder, characterized by synovitis and severe joint destruction. The pathogenesis of RA is a complex process, involving synovial cell proliferation and fibrosis, pannus formation, and cartilage and bone erosion. (This process is mediated by an interdependent network of cytokines (such as interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF-α)), prostanoids and proteolytic enzymes).

Glucosamine is used in the formation of glycosaminoglycans, proteoglycans, and glycolipids. These three substances are vital components of the synovial fluid that lubricates a joint and the cartilage that provides the smooth surface at the ends of the bones that form a joint.

It is thought that taking glucosamine in the form of glucosamine sulphate can increase production of glycosaminoglycans, proteoglycans, and glycolipids Glucosamine is produced in the body and is used in cells within the cartilage of the joints. If glucosamine is to be taken as a supplement it has to get into those cells.