Glucosamine

Studies on Glucosamine

Glucosamine is able to suppress platelet aggregation, release of granule constituents, thromboxane A2 production, calcium mobilization and phosphorylation of Syk possibly via the inhibition of ADP-binding to the receptors. Glucosamine could be expected as a novel anti-platelet agent for thrombotic disorders due to its suppressive actions on platelets.
Food Chem Toxicol. 2005 Feb;43(2):187-201.


Glucosamine effects in humans: a review of effects on glucose metabolism, side effects, safety conside rations and efficacy.

Anderson JW, Nicolosi RJ, Borzelleca JF.
Department of Internal Medicine, University of Kentucky, 1030 South Broadway, Suite 5, Lexington KY 40504-2681, USA.

Glucosamine is widely used to relieve symptoms from osteoarthritis. Its safety and effects on glucose metabolism are critically evaluated in this review. The LD-50) of oral glucosamine in animals is approximately 8000mg/kg with no adverse effects at 2700mg/kg for 12 months. Because altered glucose metabolism can be associated with parenteral administration of large doses of glucosamine in animals and with high concentrations in in vitro studies, we critically evaluated the clinical importance of these effects. Oral administration of large doses of glucosamine in animals has no documented effects on glucose metabolism. In vitro studies demonstrating effects of glucosamine on glucose metabolism have used concentrations that are 100-200 times higher than tissue levels expected with oral glucosamine administration in humans. We reviewed clinical trial data for 3063 human subjects. Fasting plasma glucose values decreased slightly for subjects after oral glucosamine for approximately 66 weeks. There were no adverse effects of oral glucosamine administration on blood, urine or fecal parameters. Side effects were significantly less common with glucosamine than placebo or non-steroidal anti-inflammatory drugs (NSAID). In contrast to NSAID, no serious or fatal side effects have been reported for glucosamine. Our critical evaluation indicates that glucosamine is safe under current conditions of use and does not affect glucose metabolism.

The use of glucosamine therapy in osteoarthritis.

Zerkak D, Dougados M. J Bone Miner Metab. 2002;20(5):298-302.
Rheumatology B Department, Rene Descartes University, AP-HP Cochin Hospital, 27 rue du Faubourg Saint Jacques, Paris 75014, France. maxime.dougados@cch.ap-hop-paris.fr.
Glucosamine products have been used extensively for the management of pain in osteoarthritis. This paper reviews the most recent clinical and experimental studies regarding its efficacy and safety. Although clinical trials include methodologic flaws and publication bias, glucosamine is likely an effective therapy for the symptomatic management of osteoarthritis.

The effect of active absorbable algal calcium (AAA Ca) with collagen and other matrix components on back and joint pain and skin impedance.

Fujita T, Ohue M, Fujii Y, Miyauchi A, Takagi Y.
Katsuragi Hospital, 250 Makami-cho, Kishiwada, Osaka 596-0842, Japan.

The effect of active absorbable algal calcium (AAA Ca) with collagen and other matrix components on aging-associated skin changes and backache and joint pain was tested in a case-controlled study of 40 test subjects and 40 age-matched control subjects (mean age, 65 years) complaining of backache and knee joint pain due to osteoarthritis, spondylosis deformans, and/or osteoporosis. Supplementation with 900 mg calcium (given as AAA Ca) and 3.5 g collagen and other matrix components, including glucosamine, daily for 4 months resulted in a marked alleviation of subjective pain, assessed by the face scale. A fall of skin impedance in response to exercise loads, such as standing up, walking, squatting, and climbing up and down stairs, reported as an objective manifestion of pain, was also alleviated. The basal skin impedance, which increases with age, was significantly reduced in response to the Ca-collagen-matrix supplementation, suggesting a change of skin properties similar to rejuvenation, along with subjective smoothening and moistening of the skin. Urinary excretion of N-terminal crosslinking telopeptide of type I collagen (NTx) was decreased in the Ca-collagen-matrix supplementation group, but not in the control group. In addition to calcium suppression of parathyroid hormone, preventing bone resorption, collagen, acting on the intestinal lymphatic system, may protect collagen from degradation through the inhibition of cytokine-induced release of metalloproteinases, including collagenase.

Glucosamine: an ingredient with skin and other benefits.

J Cosmet Dermatol. 2006 Dec;5(4):309-15. Bissett DL.
Procter & Gamble Co., Miami Valley Laboratories, Cincinnati, OH 45252, USA.

Both glucosamine and its derivative N-acetyl glucosamine are amino-monosaccharides that serve key biochemical functions on their own and as substrate precursors for the biosynthesis of polymers such as glycosaminoglycans (e.g., hyaluronic acid) and for the production of proteoglycans. Glucosamine has an excellent safety profile and has been shown to provide benefits in several clinical disorders. Glucosamine compounds have been reported to have several beneficial effects on the skin or skin cells. Because of its stimulation of hyaluronic acid synthesis, glucosamine has been shown to accelerate wound healing, improve skin hydration, and decrease wrinkles. In addition, as an inhibitor of tyrosinase activation, it inhibits melanin production and is useful in treatment of disorders of hyperpigmentation. Mechanistically, glucosamine also has both anti-inflammatory and chondroprotective effects. Clinical trials have shown benefit in using oral glucosamine supplementation to improve symptoms and slow the progression of osteoarthritis in humans. Glucosamine has also been used to prevent and treat osteoarthritis in animals. Based on other observations, glucosamine has been suggested for additional clinical uses, including treatment of inflammatory bowel disease, migraine headaches, and viral infections. The current clinical uses for topical and oral glucosamine compounds and the mechanistic rationale for these uses are reviewed here.

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