Effect of a dietary supplement containing glucosamine hydrochloride, chondroitin sulfate and quercetin glycosides on symptomatic knee osteoarthritis: a randomized, double-blind, placebo-controlled study.

Abstract

BACKGROUND:

Oral glucosamine and chondroitin sulfate, alone and in combination, have been used worldwide for the treatment of osteoarthritis (OA), but their efficacy is controversial. This clinical study was aimed at investigating the potential of a dietary supplement containing glucosamine and chondroitin sulfate in combination with derivatives of quercetin, a naturally occurring flavonoid, (GCQ supplement) for knee OA care.

RESULTS:

A randomized, double-blind, placebo-controlled study was conducted in 40 Japanese subjects with symptomatic knee OA. Subjects were randomly assigned to GCQ supplement (1200 mg glucosamine hydrochloride, 60 mg chondroitin sulfate and 45 mg quercetin glycosides per day) or placebo and the treatment and follow-up were continued for 16 weeks. The results of symptomatic efficacy assessment based on Japanese Orthopaedic Association criteria showed that scores for two of the four symptom/function subscales, as well as the aggregate scores, were significantly improved at week 16 or earlier in the GCQ group compared to the placebo group. Moreover, analyses of cartilage metabolism biomarkers showed a trend of improvement in type II collagen synthesis/degradation balance in the GCQ group during follow-up.

CONCLUSION:

GCQ supplement was thought to be more effective than placebo in decreasing the intensity of knee OA-associated clinical symptoms.

• Authors: Noriyuki Kanzaki, Kayo Saito, Akifumi Maeda, Yoshinori Kitagawa, Yoshinobu Kiso, Keita Watanabe, Akihito Tomonaga, Isao Nagaoka, Hideyo Yamaguchi
• Journal: Journal of the science of food and agriculture (J Sci Food Agric) Vol. 92 Issue 4 Pg. 862-9 (Mar 15 2012) ISSN: 1097-0010 [Electronic] England
• PMID: 21969261 (Publication Type: Journal Article, Randomized Controlled Trial)
• Copyright: Copyright © 2011 Society of Chemical Industry.

Chemical References

• Antirheumatic Agents
• Biomarkers
• Collagen Type II
• Glycosides
• Peptide Fragments
• Chondroitin Sulfates
• Quercetin
• Glucosamine

Topics

• Adult
• Aged
• Aged, 80 and over
• Antirheumatic Agents (adverse effects, chemistry, therapeutic use)
• Arthralgia (etiology, prevention & control)
• Biomarkers (blood, urine)
• Chondroitin Sulfates (adverse effects, therapeutic use)
• Collagen Type II (blood, urine)
• Dietary Supplements (adverse effects)
• Double-Blind Method
• Female
• Glucosamine (adverse effects, therapeutic use)
• Glycosides (adverse effects, chemistry, therapeutic use)
• Humans
• Knee Joint (physiopathology)
• Male
• Middle Aged
• Osteoarthritis, Knee (blood, diet therapy, physiopathology, urine)
• Peptide Fragments (blood, urine)
• Quercetin (adverse effects, chemistry, therapeutic use)
• Severity of Illness Index