Glucosamine and Arthritis

• Glucosamine is one of the most widely marketed nutritional supplements for arthritis and other problems of the bones and joints. Glucosamine is a naturally occurring substance that is usually derived from shellfish and is found in joint and connective tissue. Since glucosamine is a precursor of glycosaminoglycans, which are a primary component of joint cartilage, the logic is that glucosemine supplements help the body to rebuild and repair connective tissue and thereby fight arthritis. However, although many studies have been done on glucosamine, there has been no specific demonstration of any exact mechanism of how glucosamine helps arthritis.
  
  

Studies of Glucosamine for Arthritis

• According to a 3-year study done at Charles University in the Czech Republic, glucosamine was found to stop the joint space narrowing in the knees of patients who suffered from arthritis of the knee. In a study on rabbits that were surgically altered to have osteoartritis at Bernard University in France, the rabbits that were treated with glucosamine were found to have smaller lesions than the control group, leading the researchers to conclude that glucosamine reduces cartilage destruction. The largest study to date, a $12.5 million study by the National Institutes of Health (NIH), studied the use of glucosamine on arthritis at 16 locations across the U.S. over a 5-year period. The study had mixed results, finding that most patients had effects from the glucosamine that were similar to the effects from a placebo, although a small group with moderate to severe arthritic pain seemed to experience strong relief from glucosamine.
  
  

How Glucosamine Works

• Although there is no in vivo (in people) demonstration yet as to how glucosamine affects arthritis, there are several actions that have been observed in test tube studies that may point to how glucosamine helps arthritis. Glucosamine was shown to stimulate growth of protoglycans in human cartilage tissue in vitro by the Rotta Research Lab in Italy. Protoglycans are one of the main protein building blocks found in human cartilage. In another study at Michigan State University, glucosamine was studied on gene expressions of osteoarthritis on bovine cartilage cultures. The researchers concluded after 2 weeks that the glucosamine suppressed inflammation response markers and helped prevent certain enzyme degradation.