University of Utah School of Medicine, Salt Lake City, UT, USA.
Osteoarthritis Cartilage. 2010 Mar;18(3):297-302. doi: 10.1016/j.joca.2009.10.013. Epub 2009 Nov 10.
As part of the National Institutes of Health (NIH)-sponsored Glucosamine/Chondroitin sulfate Arthritis Intervention Trial (GAIT) our objective here was to examine (1) the pharmacokinetics (PK) of glucosamine (GlcN) and chondroitin sulfate (CS) when taken separately or in combination as a single dose in normal individuals (n=29) and (2) the PK of GlcN and CS when taken as a single dose after 3 months daily dosing with GlcN, CS or GlcN+CS, in patients with symptomatic knee pain (n=28).
The concentration of GlcN in the circulation was determined by established fluorophore-assisted carbohydrate electrophoresis (FACE) methods. The hydrodynamic size and disaccharide composition of CS chains in the circulation and dosage samples was determined by Superose 6 chromatography and FACE.
We show that circulating levels of CS in human plasma are about 20 microg/ml. Most significantly, the endogenous concentration and CS disaccharide composition were not detectably altered by ingestion of CS, when the CS was taken alone or in combination with GlcN. On the other hand, the Cmax (single-dose study) and AUC values (multiple-dose study) for ingested GlcN were significantly reduced by combination dosing with CS, relative to GlcN dosing alone.
We conclude that pain relief perceived following ingestion of CS probably does not depend on simultaneous or prior intake of GlcN. Further, such effects on joint pain, if present, probably do not result from ingested CS reaching the joint space but may result from changes in cellular activities in the gut lining or in the liver, where concentrations of ingested CS, or its breakdown products, could be substantially elevated following oral ingestion. Moreover, since combined dosing of GlcN with CS was found to reduce the plasma levels seen with GlcN dosing alone, any improved pain relief by combination dosing cannot be explained by higher circulating concentrations of GlcN.
作为美国国立卫生研究院（NIH）赞助的氨基葡萄糖/硫酸软骨素关节炎干预试验（GAIT）的一部分，我们的目的是检查（1）在正常个体中（n=29）分别或作为单一剂量同时服用氨基葡萄糖（GlcN）和硫酸软骨素（CS）时的药代动力学（PK），以及（2）在 3 个月每日服用 GlcN、CS 或 GlcN+CS 后作为单一剂量服用时的 GlcN 和 CS 的 PK 在有症状的膝关节疼痛患者中（n=28）。
通过建立的荧光辅助碳水化合物电泳（FACE）方法确定循环中 GlcN 的浓度。通过 Superose 6 色谱和 FACE 确定循环和剂量样品中 CS 链的流体力学尺寸和二糖组成。
我们表明，人血浆中环己糖胺的浓度约为 20μg/ml。最重要的是，当 CS 单独或与 GlcN 一起服用时，CS 的摄入并没有可检测到的改变内源性浓度和 CS 二糖组成。另一方面，与单独给予 GlcN 相比，CS 联合给药时摄入的 GlcN 的 Cmax（单次剂量研究）和 AUC 值（多次剂量研究）显着降低。
我们得出的结论是，摄入 CS 后感知到的疼痛缓解可能不依赖于同时或之前摄入 GlcN。此外，如果存在对关节疼痛的这种影响，它可能不是由于摄入的 CS 到达关节空间，而是可能来自胃肠道内层或肝脏中的细胞活动的变化，其中摄入的 CS 或其分解产物的浓度可能在口服后大大升高。此外，由于 GlcN 与 CS 联合给药被发现降低了单独给予 GlcN 时的血浆水平，因此联合给药的任何改善的疼痛缓解都不能用更高的循环 GlcN 浓度来解释。
