Specific primer sets used in this study.

Chondroitin sulfate (CS) is a glycosaminoglycan, and CS derived from various animal species is used in drugs and food supplements to alleviate arthralgia. The CS is a high molecular weight compound, and hydrolysis of CS by intestinal microbiota is thought to be required for absorption in mammalians. Chondroitin sulfate oligosaccharides (Oligo-CS) are produced by hydrolysis with subcritical water from CS isolated from a species of skate, Raja pulchra for the improvement of bioavailability. The present study conducted in vitro experiments using murine cell lines, to compare the biological activities of Oligo-CS and high molecular weight CS composed with the similar disaccharide isomer units of D-glucuronic acid and N-acetyl-D-glucosamine (CS-C). The results show that Oligo-CS inhibits osteoclast differentiation of RAW264 cells significantly at lower concentrations than in CS. The cell viability of a myoblast cell line, C2C12 cells, was increased when the cells were grown in a differentiated medium for myotubes with Oligo-CS, where there were no effects on the cell viability in CS. These results suggest that in vitro Oligo-CS exhibits stronger bioactivity than high-molecular weight CS.

硫酸软骨素（Chondroitin sulfate, CS）是一类糖胺聚糖，源自不同动物物种的CS已被应用于药物与食品补充剂中，用于缓解关节疼痛。CS属于高分子量化合物，哺乳动物对其的吸收被认为需要肠道菌群对其进行水解。本研究从斑鳐（Raja pulchra）中提取CS，通过亚临界水水解法制备得到硫酸软骨素寡糖（Oligo-CS），以提升其生物利用度。为比较Oligo-CS与由D-葡萄糖醛酸（D-glucuronic acid）与N-乙酰-D-葡萄糖胺（N-acetyl-D-glucosamine）构成的同源二糖异构单元组成的高分子量CS（CS-C）的生物学活性，本研究开展了基于小鼠细胞系的体外实验。实验结果显示，相较于高分子量CS，Oligo-CS在更低浓度下即可显著抑制RAW264细胞的破骨细胞分化。成肌细胞系C2C12细胞在添加了Oligo-CS的肌管分化培养基中培养时，细胞活力得以提升；而在添加了CS的培养基中培养时，细胞活力无显著变化。上述结果表明，在体外实验体系中，Oligo-CS的生物学活性强于高分子量CS。