MICROgenics Glucosamine Plus Joint Formula

Healthy joints

Healthy joints have a glassy smooth coating of cartilage over the ends of bones, stopping them rubbing together during movement. The joint space is lined with a synovial membrane that secretes synovial fluid to help reduce friction. Five percent of cartilage is made up of cartilage cells (chondrocytes) and the remaining 95% is a surrounding watery matrix that contains protein and carbohydrate complexes (proteoglycans) and fibrous proteins (type II collagen). Proteoglycans trap water and collagen provides structural strength. Cartilage does not have a blood supply and receives nutrients through a process of diffusion, in which nutrients diffuse out from the blood vessels in the synovial membranes.

How cartilage is made

Chondrocytes regulate the production of new cartilage by making proteoglycans and collagen and also by secreting enzymes that stimulate breakdown of old tissue and replacement with new. Chondrocytes convert glucose and amino acids into glucosamine, galactose and glucuronic acid, which are then converted to hyaluronic acid and the glycosaminoglycans (GAGs), which are chondroitin sulfate and keratan sulfate. GAGs are secreted into the extracellular matrix, where chondroitin sulfate and keratan sulfate attach to protein chains to form proteoglycans. Proteoglycans have a structure similar to a bottlebrush, with chondroitin sulfate and keratan sulfate making up the bristles, and they function to attract and trap water. Proteoglycans are anchored to long chains of hyaluronic acid and interwoven with rope-like collagen fibres.

Osteoarthritis

Arthritis affects around 3 million people in Australia, about 15% of the population.¹ Osteoarthritis is a degenerative joint condition that occurs mainly in people aged over 50 years and involves the breakdown of cartilage in one or more joints, causing swelling, pain, stiffness, and the development of bony nodules around the affected joint.

Osteoarthritis is the leading cause of pain and disability among the elderly in Australia and is the third leading cause of life-years lost due to disability.¹ It is estimated that about 19,000 hip and 20,000 knee replacements are performed for osteoarthritis in Australia each year.¹

In the early stages of osteoarthritis, chondrocytes begin dividing excessively and become very active, producing increased amounts of proteoglycans and cartilage that fails to mature normally. As the disease progresses, enzymes that break down cartilage become overactive. Inflammatory cytokines are produced and these increase production of the inflammatory prostaglandin E2 (PGE2) from arachidonic acid, which contributes to loss of cartilage. Eventually, more cartilage is broken down than can be repaired, bone surfaces become exposed, bone spurs develop and the inflammatory process continues, causing ongoing tissue destruction, swelling, pain, stiffness, and loss of movement.

Nutrients for healthy bones and joints

• Glucosamine
  

  Glucosamine has been shown to normalise cartilage metabolism, rebuild experimentally damaged cartilage and to have antioxidant and mild anti-inflammatory properties.² In laboratory studies, glucosamine has shown anti-inflammatory activity by suppressing PGE2 and partly suppressing nitric oxide production in human joint tissue.³

  
  

  Glucosamine has been used in a number of clinical trials for osteoarthritis. It has been shown to relieve pain and other arthritic symptoms and reduce progressive loss of cartilage, the effective dose being 1500 mg daily.⁴ The first Cochrane review concluded that glucosamine was effective and safe but a later review published in 2005 was not able to conclude, on the basis of current research, that glucosamine was effective but did report some positive results.5 In four trials that compared glucosamine to non-steroidal anti-inflammatories, a glucosamine preparation was found to be superior in two and equivalent in two and the same preparation was able to slow radiological progression of osteoarthritis of the knee over a three year period. Comparing glucosamine to the standard anti-inflammatory medication for osteoarthritis, glucosamine was effective and better tolerated.6 A review of clinical trials that measured changes in joint structure found evidence that glucosamine can reduce the risk of progression of osteoarthritis by 54%.7 Researchers have recommended that glucosamine and chondroitin should be used as viable first-line treatment options for knee osteoarthritis, especially for patients who are sensitive to anti-inflammatory medication.⁴

• Boron
  

  Boron is a trace element that interacts in the body with vitamin D, calcium, magnesium, phosphorus, copper, methionine, and arginine. It appears to be a regulator of bone density and calcium metabolism, helping to maintain calcium levels in blood and reducing calcium losses in urine. In a small trial of 20 patients, boron supplementation was associated with subjective improvement in arthritis symptoms in half the subjects.⁸

• Copper
  

  Copper forms part of superoxide dismutase, a key antioxidant enzyme system and is a cofactor for lysyl oxidase that strengthens connective tissue by promoting cross-linking.

• Manganese
  

  Manganese is an essential trace element that acts as a cofactor for the glycosyltransferase enzymes required for proteoglycan synthesis in cartilage and helps in the glycosylation of hydroxyproline residues necessary for formation of collagen. Manganese also forms manganese superoxide dismutase (Mn-SOD), an important antioxidant that is activated in joint fluid in osteoarthritis and may be up-regulated to counter excessive free radical formation.⁹

References:

1. March LM & Bagga H. Epidemiology of osteoarthritis in Australia. MJA 2004;180(5 Suppl):S6-S10
2. Rovati LC. The clinical profile of glucosamine sulphate as a selective symptom-modifying drug in osteoarthritis: current data and perspectives. Osteoarthritis Cartilage 1997;5:72.
3. Nakamura H, Shibakawa A, Tanaka M, Kato T, Nishioka K. Effects of glucosamine hydrochloride on the production of prostaglandin E2, nitric oxide and metalloproteases by chondrocytes and synoviocytes in osteoarthritis. Clin Exp Rheumatol. 2004 May-Jun;22(3):293-9.
4. Richy F et al. Structural and symptomatic efficacy of glucosamine and chondroitin in knee osteoarthritis. Arch Intern Med 2003; 163:1514-1522.
5. Towheed TE et al. Glucosamine therapy for treating osteoarthritis. The Cochrane Database of Systematic Reviews 2005, Issue 2.
6. Matheson AJ, Perry CM. Glucosamine: a review of its use in the management of osteoarthritis. Drugs Aging 2003;20:1041-1060.
7. Poolsup N, Suthisisang C, Channark P, Kittikulsuth W. Glucosamine long-term treatment and the progression of knee osteoarthritis: systematic review of randomized controlled trials. Ann Pharmacother. 2005 Jun;39(6):1080-7
8. Travers RL, Rennie GC, Newnham RE. Boron and arthritis: the result of a double-blind pilot study. J Nutr Med 1990;1:127-132.
9. Ostalowska A, Birkner E, Wiecha M, et al. Oxidant and anti-oxidant systems of synovial fluid from patients with knee post-traumatic arthritis. J Orthop Res. 2007 Jun;25(6):804-12.