Chondroitin 4-sulfate

Absorption

Chondroitin sulfate is absorbed from the gastrointestinal tract. The absorbed portion reaches a ratio of 10% as unchanged chondroitin sulfate and 90% as depolymerized low-molecular-weight derivatives. This absorption depends on the sulfation status. The bioavailability of chondroitin sulfate ranges from 10-20% following oral administration. Reports have shown a consistent accumulation of the compound in joint tissue. The steady-state is attained after 3-4 days and it takes around 3-6 months to obtain the maximal effect.
After intramuscular administration of chondroitin sulfate, the peak plasma level of 3.8 mcg/ml was reached after 90 min. When given orally, the peak plasma concentration of 4.6 mcg/ml was reached after 240 min.

Toxicity

Chondroitin sulfate does not present a carcinogenic potential. On tolerability assays, it has been shown to present great safety and good tolerability without significant severe side effects.

Description

Chondroitin 4-sulfate is a natural polymer of a disaccharide consisting of glucuronic acid and N-acetyl glucosamine which is sulfated either in the 4 or 6 position. It is a glycosaminoglycan considered as a symptomatic slow-acting drug for osteoarthritis (SYSADOA).

Chemical properties

White or yellowish amorphous powder. Tasteless, odorless, hygroscopic, soluble in water, insoluble in organic solvents such as ethanol, acetone, ether, etc. Optical rotation -25°-+35°(c=1, H2O). There are characteristic absorption peaks at 725cm-1, 852cm-1 and 930cm-1 by infrared spectroscopy.

The Uses of Chondroitin 4-sulfate

sodium chondroitin sulfate is described as a skin-conditioning agent, with possible anti-inflammatory properties. It can be found in such products as moisturizers and night skin care preparations. It is a derivative of natural mucopolysaccharides.

Background

Chondroitin sulfate is a glycosaminoglycan considered as a symptomatic slow-acting drug for osteoarthritis (SYSADOA). The SYSADOA status suggested a pain relief and increased joint mobility after a relative long regular administration, as well as a long-lasting effect after the end of the treatment. Chondroitin sulfate is composed of alternating 1,3-N-acetyl-β-d-galactosamine and 1,4-β-d-glucuronic acid units which bear 4-O- and/or 6-O-sulfations at the N-acetylgalactosamine units disposed of in specific patterns. Depending on the predominating disaccharide unit, it will present different biological activities. Chondroitin sulfate is sold as an OTC dietary supplement in North America and it is a prescription drug under the EMA in Europe.

Indications

Chondroitin sulfate, used with glucosamine, is indicated to alleviate pain and inflammation from primary osteoarthritis. This supplement is reported to improve joint function and slow disease progression. Osteoarthritis is characterized by progressive structural and metabolic changes in joint tissues, mainly cartilage degradation, subchondral bone sclerosis and inflammation of synovial membrane.
Studies have proposed the potential use of chondroitin sulfate as a nutraceutical in dietary supplements.

Definition

ChEBI: Chondroitin 4'-sulfate is a chondroitin sulfate in which the site of sulfation is carbon 4 of the N-acetylgalactosamine (GalNAc) sugar. It has a role as a mouse metabolite. It is a conjugate acid of a chondroitin 4'-sulfate anion.

Preparation

Chondroitin 4-sulfate can be extracted using the following method:
Weigh pig throat and nasal cartilage and put it into a solution of 20g/L (2%) sodium hydroxide, using a ratio of 5 times the weight of the cartilage.
Soak the cartilage in the sodium hydroxide solution and stir it intermittently.
Filter the solution when the leachate reaches 5.5°Be.
Extract the residue left on the filter by adding it to the sodium hydroxide solution again and combining the filtrate.
To remove impurities such as protein, hydrolyze the solution with crude trypsin at 50°C.
Filter the solution until it becomes clear.
Adjust the pH of the solution to 6.
Add ethanol to the solution until the alcohol content reaches 75%.
Let the solution stand overnight to allow precipitation.
Centrifuge the solution to separate the precipitate.
Wash the precipitate with absolute ethanol.
Dry the precipitate at 60°C to obtain crude chondroitin sulfate.

Pharmacokinetics

In clinical trials, chondroitin sulfate has been reported a significant pain relief. Some reports have shown no slow in joint damage. The effects of chondroitin sulfate have been very controversial. One of the characteristics of chondroitin is a slow onset of action with a maximal effect attained after several months. Chondroitin sulfate has been reported to have anti-inflammatory properties by reducing the synovitis and prevent proinflammatory cytokine up-regulation in arthritis models.
It is also registered an anabolic effect of chondroitin sulfate in which it induces the synthesis of hyaluronate in synovial cells, it increases type II collagen and proteoglycan synthesis.

Metabolism

Chondroitin sulfate is not metabolized by cytochrome P450. Reports have indicated the presence in plasma of mono-, oligo- and polysaccharides with a molecular weight of less of 5 kDa which are derived from the partial digestion of exogenous chondroitin sulfate. The reported degradation of chondroitin sulfate seems to be very complex and led by the formation of smaller digestion derivatives of the original form.

References

1. Inhibition of Spiral Growth and Dissolution at the Brushite (010) Interface by Chondroitin 4-Sulfate. DOI:10.1021/acs.jpcb.8b11531
2. Evaluation of Chitosan-Based Films Containing Gelatin, Chondroitin 4-Sulfate and ZnO for Wound Healing. DOI:10.1007/s12010-017-2462-z
3. Expression and function of chondroitin 4‐sulfate and chondroitin 6‐sulfate in human glioma. DOI:10.1096/fj.201901621RRR
4. https://pubchem.ncbi.nlm.nih.gov/compound/70678540