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Our understanding of osteoarthritis is evolving. Once thought to be a degenerative, old age malady -- the result of "wear and tear" – osteoarthritis is now being viewed as a complex disease involving an imbalance or deregulation of the body's cycle of cartilage breakdown and regeneration. Osteoarthritis is generally divided into two types. "Primary" osteoarthritis involves the wearing away and roughening of articular cartilage, and "secondary" osteoarthritis is associated with a prior injury, such as rheumatoid arthritis (where the immune system attacks the synovial membranes in joints, leaving scar tissue) or physical trauma. M.J. Fredrich, MD, says that while age is probably the most significant risk factor for developing osteoarthritis, the disease "is not an inevitable part of the aging process." Other risk factors include obesity, prior injury, and a diet high in meat and milk protein.
Traditional treatment for osteoarthritis includes weight loss and non-steroidal anti-inflammatory drugs (NSAIDS) including aspirin, acetaminophen, ibuprofen and naproxen. However, long term use of these drugs can cause serious gastrointestinal bleeding and ulcers. In addition, they inhibit the formation of the PGE1 prostaglandin, the body's natural defense against arachidonic acid, known to aggravate the protective synovial membranes, causing inflammation in the joints.
The new concept of osteoarthritis, as a dysfunction of the cartilage breakdown-regeneration cycle, creates new avenues for treatment of the disease. If the cartilage is to be properly repaired, the building blocks of cartilage must be readily available. Glucosamine is a precursor to a type of molecule called a glycosaminoglycan that the body uses in the formation and repair of cartilage. Chondroitin is the most abundant glycosaminoglycan in cartilage and is responsible for its resiliency. In 1999, the National Institute of Health awarded a $6.6 million grant for the study of glucosamine.
Glucosamine
Glucosamine, manufactured in the body, is a component of all human tissues and is found in especially high concentrations in the cartilage. As a supplement taken orally, about 90% of the glucosamine is absorbed in the small intestines. This glucosamine is distributed throughout the body and, within four hours, 4% of the glucosamine has made its way into the joints. Once in the cartilage, glucosamine is incorporated into a molecule called a proteoglycan. This proteoglycan promotes joint health in two ways. It combines with sulfate (from MSM) to form the glycosaminoglycan needed to repair cartilage. And it is instrumental in forming a lubricating liquid in the joints. When there is not enough protective lubricant, cushioning is reduced and articular damage occurs.
To date, researchers have conducted more than 20 studies on glucosamine, incorporating over 3000 patients. These studies indicate that glucosamine sulfate, typically in doses of 1.5 grams (1500 mg) per day, relieves pain and inhibits the progression of osteoarthritis. Some studies report that osteoarthritis has been reversed. A double blind, three-year study reported in 1999 by the American College of Rheumatology, studied the effects of 1.5 grams of glucosamine on patients suffering from osteoarthritis of the knee. Using a scale called the Western and McMaster Osteoarthritis Index, they found that patients taking the placebo worsened by 5%, while patients taking the glucosamine improved by 15%. In addition, the researchers measured the joint space width. They found that the group taking the placebo averaged a narrowing of 0.08-0.1mm per year, while the group taking glucosamine showed an actual widening of the joint space. Perhaps most interesting is a study done by Drovanti, et al., in 1980. Eighty osteoarthritis patients were given either glucosamine or a placebo. The group given glucosamine experienced a 70% improvement in symptoms – pretty much typical of such studies. However, as part of this study the researchers examined the patients' cartilage under an electron microscope. Normal cartilage is smooth, with little debri. Cartilage taken from the patients in the placebo group exhibited folded and irregular surfaces. The cartilage taken from the glucosamine-treated group was relatively smooth with few discontinuities.
When compared to the NSAIDS drugs, glucosamine was found to be equally effective for pain relief, without the long-term adverse effects. However, glucosamine treatments are a long-term process. Effects of the treatment may start to become noticeable in two weeks; however, three to eight weeks is more common.
Recently there have been a rash of warnings about a potential risk to diabetics taking glucosamine. This concern was postulated because glucosamine is chemically similar to streptozotocin, a substance know to destroy the cells in the pancreas that produce insulin. Since osteoarthritis sufferers are often older and obese, many may have some level of glucose intolerance. The main justification for this concern is a study of hypoglycemic rats that, when injected with glucosamine, demonstrated a resistance to insulin. However, human studies have failed to substantiate this warning. In one three-year study, subjects given glucosamine daily actually reported a slight decrease in blood glucose levels.
About 5% of people taking glucosamine report adverse effects, mostly gastrointestinal in nature: constipation, diarrhea, etc. Many of these people can take glucosamine HCl (glucosamine hydrochloride). While most researchers agree that glucosamine HCl is as effective as glucosamine sulfate, they disagree on how well it is absorbed. Some say it does not absorb as well. Others say it absorbs so much better that you can take smaller doses of the glucosamine HCl. Since glucosamine (made from the shells of lobsters, crabs and other crustaceans) may deteriorate relatively easily during production, different manufacturer's production methods can greatly affect the quality of their glucosamine product.
Chondroitin
Chondroitin sulfate is the most common proteoglycan in cartilage and, because it is highly electronegative in nature, it attracts water. It is this property of water retention that gives cartilage its resilience and elasticity. Although there have not been as many studies on chondroitin as on glucosamine, the studies have shown that doses of 800-1200 mg of chondroitin reduce pain and improve joint function.
Research has led to speculation that chondroitin sulfate provides a four-fold benefit in combating osteoarthritis. 1) The increased levels of chondroitin sulfate can be used for cartilage synthesis. 2) Chondroitin sulfate might increase levels of other proteoglycans for cartilage and synovial fluid synthesis. 3) Chondroitin sulfate inhibits the activity of elastace, a chemical known to break down collagen. 4) Chondroitin sulfate decreases inflammation.
Chondroitin sulfate is not as easily absorbed as glucosamine. In fact, only about 15% of supplemented chondroitin is absorbed. Like glucosamine, chondroitin treatment is a long-term process. It may take several weeks to four months before improvement is noticed. No adverse effects are reported. Because chondroitin is harvested from the trachea of cattle, it is expensive to manufacture the quantities needed for treatment. Like glucosamine, the quality of chondroitin varies from manufacturer to manufacturer.
Many studies combine glucosamine and chondroitin and, like the studies of the supplements separately, improvement is reported with the combination of the two. However, there has been no evidence that the combination has a synergistic effect (a greater effect when combined).
MSM
Sulphur is the fourth most prevalent mineral in the body. Even though it is found in every cell in every plant and animal, it is probably the most under-appreciated mineral in our body. In its biological form, sulphur is called methylsulfonylmethane, or MSM for short.
About half of our body sulphur is concentrated in the muscles, skin and bones. It is also found in keratin, the tough substance in hair, skin and nails. Sulphur is needed for production of collagen, the primary constituent of cartilage and connective tissue. It is used in the formation of disulfide bonds that join proteins, and consequently hold connective tissue together. MSM is a key component in many amino acids, including methionine, cysteine and taurine. MSM, along with the necessary vitamins and amino acids, provides the body with the raw materials to create new cells. A body deficient in MSM cannot efficiently repair or replace damaged tissues and organs, and produces dysfunctional cells which can lead to illness.
Probably the most popular use of MSM as supplement concerns its ability to alleviate pain associated with systemic inflammatory disorders such as arthritis. MSM helps to sustain cell flow-through, allowing harmful substances such as lactic acid and toxins to flow out and nutrients to flow into cells. Therefore, it prevents the pressure buildup in cells that causes inflammation in joints and elsewhere. (For years trainers have given MSM to million-dollar racehorses before a race to prevent muscle soreness, and after a race to prevent cramping.)
MSM seems to work synergistically with glucosamine. By promoting cell flow-through, it helps glucosamine get to the joint cartilage. It then supplies the sulfate that glucosamine needs to produce glycosaminoglycans. This combination is best taken on an empty stomach.
(c) 2002 by Chip Engelmann
Copyright (c) 2001 by Chip Engelmann
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