Przed chwilą dostałem takiego maila.
Nie mam w tej chwili czasu czytać tego.
Ale proszę - podzielę sie wiedzą - nie sjestem sobkiem:
Moje pytanie było takie:
There are many specifics in the market containing apart from Glucosamine
Sulfate also Chondroitin Sulfate. Is it proven and suggested that chondrotin
may have some positive effect in joint care and what are the best products
suggested for joint care?
Dear Mr. Klein:
Thank you for your inquiry about DONA, The Original Glucosamine Sulfate.
Here is the answer to your question:
Why chondroitin sulfate is combined with glucosamine-derived compounds in
some dietary supplements? Is there a rationale to administer both
Glucosamine Sulfate and chondroitin sulfate?
Chondroitin sulfate is a glycosaminoglycan normally present in the cartilage
matrix and consisting of a high molecular weight, long chain of repeating
units of differently sulfated residues of glucuronic acid and N-acetyl
galactosamine, obtained with extraction processes from animal tissues. It is
used in some countries for the treatment of osteoarthritis on the basis of a
rationale that is speculatively similar to that of Glucosamine Sulfate,
which is difficult to understand given the major differences in
physico-chemical properties (a macromolecular tissue extract compared to the
Glucosamine Sulfate pure, low molecular weight single molecule of
semi-synthetic origin).
Actually, oral absorption of high molecular mass polymers is questionable
and pharmacokinetics studies have shown that, although absorption of a small
fraction of high molecular weight chondroitin sulfate can not be excluded,
after oral administration the largest peak consists of one of the
constituent monomers, N-acetyl-galactosamine, a derivative of glucosamine
which is therefore probably responsible for the pharmacological activity.
Very early studies had shown that N-acetyl-galactosamine may induce
metabolic activities similar to that of its precursor glucosamine, although
with a lower potency. It may be speculated therefore, that the clinical
activity reported for chondroitin sulfate in some clinical trial may be
similar to that of low dose Glucosamine Sulfate.
Anecdotal evidence claims that combination of dietary supplements containing
chondroitin sulfate and glucosamine-derivatives may offer added value in the
treatment of osteoarthritis. However, there is no scientific proof for this
claim and, on the basis of the discussion above, the rationale of such a
combination is also weak since adding chondroitin to glucosamine would mean,
at most, only to slightly increase the dose of glucosamine. Two very small
clinical trials have shown that this combination is actually effective in
the short-term treatment of osteoarthritis symptoms, but this is not
surprising given the high efficacy of Glucosamine Sulfate and that may in
part be applied to other glucosamine-derivatives. Indeed, studies with the
original Glucosamine Sulfate have shown that its effects on osteoarthritis
symptoms are so strong that even the combination with potent symptomatics
such as NSAIDs may bring no added value. Therefore, it would be necessary to
show in appropriate clinical trials that the combination with chondroitin
sulfate works better than Glucosamine Sulfate alone, which would be hard to
demonstrate.
This is particular true when the anecdotical evidence supporting the
effectiveness of such a combination refers to dietary supplements. Indeed,
research from the University of Maryland has recently detected major
deviations in the active ingredient content for several of these products.
Although this refers to both glucosamine and chondroitin, the situation for
the latter is even worse and the content of chondroitin in some of these
products is so low, if any, that the activity would be in any case given
only by the glucosamine-derivative content (provided that this is
confirmed).
To date, there is therefore no evidence, nor a rationale to support the
suggestion to combine Glucosamine Sulfate with chondroitin sulfate.
If you have any additional questions, please feel free to contact us
toll-free at 1(800)214-9600 or you can email us at
info@rottapharmaceuticals.com.
Sincerely,
Nicole M. Hoffman
Rotta Pharmaceuticals, Inc.
1340 Campus Parkway
Neptune, New Jersey 07753
Phone (732) 751-9020
Fax (732) 751-9021
nhoffman@rottapharmaceuticals.com
(Edited by FREDZIO at 4:21 pm on Jan. 23, 2003)
