The Effect of Mechanical Loading on the Metabolism of Growth Plate Chondrocytes
The Effect of Mechanical Loading on the Metabolism of Growth Plate Chondrocytes
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DOI：
10.1007/s10439-008-9462-7
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发表时间：
2008-02
影响因子：
3.8
通讯作者：
M. Ueki;N. Tanaka;K. Tanimoto;C. Nishio;Kobun Honda;Yu-Yu Lin-Yu;Y. Tanne;Satoru Ohkuma;T. Kamiya;E. Tanaka;K. Tanne
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文献类型：
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作者：
M. Ueki;N. Tanaka;K. Tanimoto;C. Nishio;Kobun Honda;Yu-Yu Lin-Yu;Y. Tanne;Satoru Ohkuma;T. Kamiya;E. Tanaka;K. Tanne
众所周知，机械载荷影响软骨内骨的形成，而软骨内骨的形成对于纵骨的生长和发育至关重要。然而，问题是机械负荷对软骨细胞代谢的影响是否取决于负荷频率。本研究旨在评价不同频率的拉伸载荷对生长板软骨细胞增殖和细胞外基质合成的影响。从4周龄雄性Wistar系大鼠的肋生长板软骨获得的软骨细胞在第4天和第11天培养，并分别用作增殖和基质形成软骨细胞。对每个阶段的软骨细胞施加不同频率的间歇性张应力。通过测量[3 H]胸苷掺入细胞来检查DNA合成。此外，胶原蛋白和蛋白多糖的合成率分别通过测量[2，3 - 3 H]脯氨酸和[35 S]硫酸盐掺入细胞来确定。在增殖期，30次/min和150次/min的间歇性张力刺激能显著促进软骨细胞DNA合成（p< 0.05），促进软骨细胞增殖。在基质形成阶段，胶原和蛋白多糖的合成也随着加载频率的增加而增强。30周/min和150周/min的间歇性张力使胶原和蛋白多糖的合成显著增加（p< 0.05或p < 0.01）。这些结果表明，生长板软骨细胞的增殖和分化受机械负荷的调节，软骨细胞的代谢随着负荷频率的增加而增强。这些结果可能有助于进一步了解软骨内骨形成的可能机制。
It is well known that mechanical loading influences the endochondral bone formation essential for the growth and development of longitudinal bones. The question was, however, asked whether the effect of mechanical loading on the chondrocyte metabolism is dependent on the loading frequency. This study was aimed at evaluating the effect of tensile loadings with various frequencies on the proliferation of growth plate chondrocytes and extracellular matrix synthesis. The chondrocytes obtained from rib growth plate cartilage of 4-week-old male Wistar strain rats were cultured by day 4 and day 11 and used as proliferating and matrix-forming chondrocytes, respectively. Intermittent tensile stresses with different frequencies were applied to each stage chondrocyte. DNA syntheses were examined by measuring the incorporation of [3H]thymidine into the cells. Furthermore, the rates of collagen and proteoglycan syntheses were determined by measuring the incorporation of [2,3-3H]proline and [35S]sulfate into the cells, respectively. At the proliferating stage, intermittent tensions with the frequencies of 30 cycles/min and 150 cycles/min significantly (p< 0.05) upregulated the syntheses of DNA, which indicates the promotion of chondrocyte proliferation. At the matrix-forming stage, collagen, and proteoglycan syntheses also enhanced with increase of the loading frequency. In particular, the intermittent tension with the frequencies of 30 cycles/min and 150 cycles/min increased significantly (p< 0.05 orp< 0.01) both the collagen and proteoglycan syntheses. These results suggest that the proliferation and differentiation of growth plate chondrocytes are regulated by the mechanical loading and that the chondrocyte metabolism enhanced with increase of loading frequency. These may give more insight into the possible mechanism leading to endochondral bone formation.