Medical Evidence
Beneficial Effect of Dietary Chondroprotective
Agents in a Rabbit Instability Model of Osteoarthritis John
S. Woodward, M.D., Scottsdale, AZ; Louis Lippiello, Phoenix, AZ;
Robert R. Karpman, MD, Phoenix, AZ. Moderator(s): Paul F Lachiewicz,
MD, Chapel Hill, NC; Roger N. Levy, MD, New York, NY.
Summary: We investigated
whether dietary supplements containing a mixture of glucosamine
HCl and chondroitin sulfate were effective disease-modifying agents
by monitoring the progression of cartilage lesions in a rabbit
instability model of osteoarthrosis. Surgical instability (Hulth)
was induced in 12 2-3 Kg NZW rabbits. Postoperatively, animals
were exercised for 1 -hour daily. Six controls were fed a standard
Harland-Teklad diet with the experimental group supplemented with
2% by weight Cosamin DS¨ (Nutramax Laboratories Inc., Baltimore,
MD.) Dietary intake averaged 190 grams/day providing 0.38 grams
glucosamine HCL and 0.304 grams sodium chondroitin sulfate/day/kg
experimental rabbit. At 16 weeks tissue sections taken through
the center of the medial condyle were evaluated quantitatively
with a modified Mankin histological-histochemical grading system
using Safranin-O stained slides. Scoring summed up the millimeter
(at 1OX) of linear involvement of lesions grouped as mild (1 -3),
moderate (4-7) or severe (> 8). Statistical analysis utilized
the Student t-test and Wilcoxon rank sum test. Results:. Histologically,
control rabbits had 2.5 mm of mild, 4.6 mm of moderate and 3.2
mm of severe lesions while animals fed Cosamin DS had scores of
3.2 mm mild, 0.4 mm moderate and 0.4 mm severe. Hence dietary
supplements of Cosamin DSO decreased the extent of moderate and
severe cartilage lesions (p < 0.02) suggesting that a mixture
of glucosamine HCL and chondroitin sulfate has significant disease-modifying
effects in this model of osteoarthrosis.
Source: Presented at the
American Academy of Orthopedic Surgeons 1999 Annual Meeting, Paper
No: 048 Friday, February 5, 1999.
Dr. Theo's Comments: This
is powerful, direct evidence of disease modification with glucosamine
HCl and chondroitin sulfate. Also shows that glucosamine sulfate
is not necessary. Hard to argue against this kind of data!