Medical Evidence
Biochemical and Pharmacokinetic Aspects
of Oral Treatment with Chondroitin Sulfate. Conte
A, Volpi N, Palmieri L, Bahous I, Ronca G Department of Biologia
Animale, University of Modena, Italy.
Summary: Chondroitin sulfate
(Condrosulf) was characterized for structure, physiochemical properties
and purity. This glycosaminoglycan has a relative molecular mass
of about 14,000, a sulfate-to-carboxyl ratio of 0.95 due to the
high percentage of monosulfated disaccharides (38% 6-monosulfate
and 55% 4-monosulfate) and a low amount of disulfated disaccharides
(1.1%) inside the polysaccharide chains. No other glycosaminoglycans
were detected in the preparation. Chondroitin sulfate was labelled
by reduction with sodium 3H-borohydride and administered by oral
route in the rat and dog. More than 70% of radioactivity was absorbed
and found in urine and tissues. The plasma radioactivity was fractionated
by size-exclusion chromatography in three fractions: radioactivity
associated with high, intermediate and low molecular mass compounds.
The peak value of the concentration of high molecular mass radioactivity
compounds in plasma was reached after 1.6 and 2.1 h for the rat
and dog, respectively. After 36 h the high molecular mass radioactivity
compounds were still present in plasma of dog and rat. After 24
h radioactivity was higher in the intestine, liver, kidneys, synovial
fluid and cartilage than in other tissues. Condroitin sulfate
was orally administered to man (healthy volunteer) in a single
daily dose of 0.8 g and in two daily doses of 0.4 g. The results
showed that both forms of administration determined a significant
increase of plasma concentration of chondroitin sulfate as compared
with predose value over a full 24 h period. Elimination constant
values and tmax (of the first administration in the case of fractionated
dose) were almost the same for the two administrations.
Source: Arzneimittelforschung
1995 Aug;45(8):918-25
Dr. Theo's Comments: Another
study to show that oral chondroitin sulfate is absorbed in humans.
