Kurz Bodo, Lemke Angelika, Kehn Melanie, Domm Christian, Patwari Parth, Frank Eliot H, Grodzinsky Alan J, Schünke Michael
Anatomisches Institut der Christian-Albrechts-Universität, Kiel, Kiel, Germany.
Arthritis Rheum. 2004 Jan;50(1):123-30. doi: 10.1002/art.11438.
To study the influence of tissue maturation and antioxidants on apoptosis in bovine articular cartilage induced by injurious compression.
Bovine articular cartilage disks were obtained from the femoropatellar groove of animals ages 0.5-23 months and placed in culture. Cartilage disks were preincubated overnight with the cell-permeable superoxide dismutase (SOD) mimetic Mn(III) porphyrin (0-12.5 microM) or alpha-tocopherol (0-50 microM) and then injured by a single unconfined compression to a final strain of 50% at a velocity of 1 mm/second. After 4 days of additional incubation, the disks were fixed and embedded for light and electron microscopy. Apoptotic cells were quantified morphologically by the appearance of nuclear blebbing on light microscopy. Biosynthetic activity was demonstrated by incorporation of radiolabeled proline. The antioxidative action of the SOD mimetic was confirmed by histologic examination of cartilage after incubation with nitroblue tetrazolium.
Injurious compression induced significantly more apoptosis in cartilage disks from newborn calves (22% of cells) than in cartilage from more mature cows (2-6%). In cartilage from 22-month-old animals, the SOD mimetic reduced the percentage of apoptotic cells induced by injury in a dose-dependent manner (complete inhibition with 2.5 microM), while alpha-tocopherol had no effect. Neither antioxidant altered protein biosynthesis or cellular ultrastructure.
Our data suggest that the apoptotic response of articular cartilage to mechanical injury is affected by maturation and is mediated in part by reactive oxygen species. The antioxidative status of the tissue might be important for the prevention of mechanically induced cell death in articular cartilage.
研究组织成熟度和抗氧化剂对损伤性压缩诱导的牛关节软骨细胞凋亡的影响。
从0.5 - 23月龄动物的股骨髌股沟获取牛关节软骨盘并进行培养。软骨盘用可穿透细胞的超氧化物歧化酶（SOD）模拟物锰（III）卟啉（0 - 12.5微摩尔）或α-生育酚（0 - 50微摩尔）预孵育过夜，然后以1毫米/秒的速度进行单次无侧限压缩损伤至最终应变50%。再孵育4天后，将软骨盘固定并包埋用于光镜和电镜检查。通过光镜下核出泡的出现对凋亡细胞进行形态学定量。通过掺入放射性标记的脯氨酸来证明生物合成活性。用硝基蓝四氮唑孵育后对软骨进行组织学检查，证实了SOD模拟物的抗氧化作用。
与更成熟奶牛的软骨（2% - 6%）相比，损伤性压缩在新生小牛的软骨盘中诱导的凋亡明显更多（22%的细胞）。在22月龄动物的软骨中，SOD模拟物以剂量依赖性方式降低了损伤诱导的凋亡细胞百分比（2.5微摩尔时完全抑制），而α-生育酚没有效果。两种抗氧化剂均未改变蛋白质生物合成或细胞超微结构。
我们的数据表明，关节软骨对机械损伤的凋亡反应受成熟度影响，部分由活性氧介导。组织的抗氧化状态对于预防关节软骨机械诱导的细胞死亡可能很重要。
