What is glucosamine?
Glucosamine is an amino sugar. In the human body, it acts as an important precursor when glycosylated proteins and lipids are synthesised. Due to this effect, glucosamine is commonly used by persons suffering from osteoarthritis. Different studies have come to different results regarding its usefulness in osteoarthritis treatments, so you may wish to discuss your problems with more than one doctor to get a broader input.

What is glucosamine good for?
Glucosamine is currently being studied in countless research programs world wide, but we still know very little about its exact mechanisms. Several clinical trials have been carried out where glucosamine has been tested as a potential medical therapy for osteoarthritis, with conflicting results. The medical society is therefore currently discussing whether or not to use glucosamine as a treatment for osteoarthritis.

During the 1980s and 1990s, several clinical trials showed a link between glucosamine and successful osteoarthritis treatment, but they were all carried out by Rottapharm who is the European patent holder of glucosamine and have received quite harsh criticism.

The National Institutes of Health (an agency of the United States Department of Health and Human Services) has funded a 6-month long, multicenter clinical trial to find out more about the effects of chondroitin sulfate, glucosamine HCl, and the combination of both on painful knee osteoarthritis. In this study the effects where compared to placebo as well as to celecoxib, a non-steroidal anti-inflammatory drug used in the treatment of osteoarthritis and rheumatoid arthritis. The study showed that patients who used glucosamine HCl, chondroitin sulphate or a combination of both did not show any statistically significant improvement compared to the patients who received a placebo. Secondary analysis of a subgroup did however indicate that supplements might be helpful for patients suffering from moderate to severe pain. It should be noted that the National Institutes of Health never tested glucosamine sulphate, the supplement used in several trials where glucosamine have been shown to have beneficial results in patients suffering from osteoarthritis.

What is glucosamine in biochemical terms?
The chemical composition of glucosamine is C6H13NO5. It acts as biochemical precursor for all sugars that contain nitrogen. In the human body, glucosamine-6-phosphate is synthesized from fructoise-6-phospahate and glutamine, during the first step of the so called hexosamine biosnthesis pathway. The result is UDP-N-acetylglucosamine, which is then turned into glycolipids, proteoglycans and glycosaminoglycans.

Glycolipids are carbohydrade-attached lipids. In our bodies, glycolipids are responsible for providing energy. They also serve as important markers for cellular recognition. Glycolipids will not only act as recognition sites for certain chemicals; they will also attach cells to each other in order to create tissue, while simultaneously making sure that the cell membranes remains stable.

Proteoglycans are a type of glycoproteins. They make up the so called “extracellular matrix” in humans, which means that they act as filler substances between the cells. They will for instance form large complexes by attaching themselves to collagen.

Glycosaminoglycans are important for all vertebrates since they make up an imperative part of our connective tissue. Glycosaminoglycans (commonly referred to as GAGs) are very long polysaccharides that contain within them a remarkably high density of negative charge. The negative charge is due to a combination of the sulfate group and the carboxylate group in the GAG.