Chiba Kazuhiro, Masuda Koichi, Andersson Gunnar B J, Momohara Shigeki, Thonar Eugene J
Department of Orthopedic Surgery, Rush Medical College at Rush University Medical Center, Chicago, IL 60612, USA.
Spine J. 2007 Nov-Dec;7(6):694-700. doi: 10.1016/j.spinee.2006.09.005. Epub 2006 Dec 22.
One of the advantages of chemonucleolysis for the treatment of a herniated intervertebral disc is the potential for the disc to self-repair. It has been suggested that the enzymes used for chemonucleolysis differentially affect the potential of the disc cells to promote repair.
To test the ability of nucleus pulposus and anulus fibrosus cells to repair the extracellular matrix degraded in vitro by either chondroitinase ABC or chymopapain.
An alginate cell culture system was used to monitor the progress of matrix repair after chemonucleolysis in vitro.
Rabbit nucleus pulposus or anulus fibrosus cells precultured for 10 days in alginate gel were briefly exposed to low concentrations of chondroitinase ABC or chymopapain and then returned to normal culture conditions for up to 4 weeks. At each time point, the contents of DNA and matrix macromolecules and proteoglycan synthesis were measured.
The DNA content of enzyme-treated alginate beads during the following 4 weeks of culture was higher in the chondroitinase ABC group than in the chymopapain group (NP, p<.01, and AF, p<.05). The content of proteoglycan in beads containing nucleus pulposus and anulus fibrosus cells in the chondroitinase ABC group was higher than that in the chymopapain group (NP and AF, p<.001). The rate of proteoglycan synthesis and the content of collagen did not, however, differ between those two groups.
Intervertebral disc cells exposed to chondroitinase ABC reestablish a matrix richer in proteoglycan than cells exposed to chymopapain. This may be because of differences in the substrate spectrum of each enzyme. Although these results cannot be translated directly to the in vivo situation, they suggest the possibility that cells in discs subjected to chondroitinase ABC-induced chemonucleolysis retain a greater ability to replenish their extracellular matrix with proteoglycans than cells in discs exposed to chymopapain.
化学髓核溶解术治疗椎间盘突出症的优点之一是椎间盘具有自我修复的潜力。有人提出，用于化学髓核溶解术的酶对椎间盘细胞促进修复的潜力有不同影响。
测试髓核细胞和纤维环细胞修复体外被软骨素酶ABC或木瓜凝乳蛋白酶降解的细胞外基质的能力。
使用藻酸盐细胞培养系统监测体外化学髓核溶解术后基质修复的进程。
将在藻酸盐凝胶中预培养10天的兔髓核或纤维环细胞短暂暴露于低浓度的软骨素酶ABC或木瓜凝乳蛋白酶，然后恢复到正常培养条件下长达4周。在每个时间点，测量DNA、基质大分子和蛋白聚糖合成的含量。
在接下来4周的培养中，软骨素酶ABC组酶处理的藻酸盐珠中的DNA含量高于木瓜凝乳蛋白酶组（髓核，p<0.01；纤维环，p<0.05）。软骨素酶ABC组含有髓核和纤维环细胞的珠中蛋白聚糖的含量高于木瓜凝乳蛋白酶组（髓核和纤维环，p<0.001）。然而，这两组之间蛋白聚糖合成速率和胶原蛋白含量没有差异。
暴露于软骨素酶ABC的椎间盘细胞重建的基质比暴露于木瓜凝乳蛋白酶的细胞富含更多蛋白聚糖。这可能是由于每种酶的底物谱不同。尽管这些结果不能直接转化为体内情况，但它们表明，接受软骨素酶ABC诱导的化学髓核溶解术的椎间盘细胞比暴露于木瓜凝乳蛋白酶的椎间盘细胞保留了更强的用蛋白聚糖补充其细胞外基质的能力。
