低硒和/或低碘对子三代大鼠关节软骨细胞凋亡的影响

Effects of Selenium and/or Iodine Deficiency on Chondrocyte Apoptosis in Rats

目的研究低硒和/或低碘对子三代大鼠软骨细胞凋亡的影响。方法将48只断乳SD大鼠随机分为低硒组、低碘组、低硒低碘组和对照组4组,采用末端脱氧核苷酸转移酶介导的缺口末端标记(TUNEL)技术和免疫组织化学方法检测各组子三代大鼠关节软骨细胞的凋亡率、Bcl-2和Bax蛋白表达及其分布情况。结果与对照组相比,低硒组、低碘组及低硒低碘组子三代大鼠关节软骨表层和中层软骨细胞凋亡增多,尤以中层增多更显著(P<0.05),低硒组、低碘组及低硒低碘组间细胞凋亡阳性率差异无统计学意义(P>0.05);低硒组、低碘组及低硒低碘组子三代大鼠关节软骨表层和中层Bcl-2和Bax表达阳性细胞数较对照组明显增多(P<0.05),低硒组、低碘组及低硒低碘组间Bcl-2和Bax表达阳性细胞数差异无统计学意义(P>0.05)。结论低硒和/或低碘可能诱导大鼠关节软骨细胞异常凋亡。

Objective To explore the effects of selenium and/or iodine deficiency on chondrocyte apoptosis in articular cartilage in rats. Methods Forty-eight Spraguee-Dawley rats were randomly divided into selenium deficiency group, iodine deficiency group, combined selenium and iodine deficiency group, and control group. Chondrocyte apoptosis was detected by terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling （TUNEL） method, and Bcl-2 and Bax in articular cartilage were stained by immunohistochemistry in F3 generation of rats. Results In articular cartilage , the positive rate of apoptotic chondrocytes stained by TUNEL in the upper and middle zones in selenium deficiency group, iodine deficiency group, and combined selenium and iodine deficiency group （ all P 〈 0. 05 ） were significantly higher than that in control group. The apoptotic chondrocytes were prominent in the middle zone. The positive percentage of chondrocytes apoptosis was not significantly different among these three groups （ P 〉 0. 05 ）. Compared with the control group, the expressions of both Bcl-2 and Bax were significantly higher in the upper and middle zone in the selenium deficiency group, iodine deficiency group, and combined selenium and iodine deficiency group （ all P 〈 0.05 ） ; however, the expressions of Bcl-2 and Bax were not significantly different among these three groups （P 〉 0. 05 ）. Conclusion Selenium and/or iodine deficiency may induce chondrocyte apoptosis.