Effects of cyclic tensile stress on metabolism and apoptosis of chondrocytes inrat
10.3760/cma.j.issn.0254-1424.2016.11.004
- VernacularTitle:周期性拉伸应力对大鼠软骨细胞代谢及凋亡的影响
- Author:
Yongbin HE
;
Shengyao LIU
;
Songyun DENG
;
Shaoyong XU
;
Lei XU
;
Guoxin NI
- Keywords:
Cyclic tensile stress;
Chondrocyte;
Apoptosis;
Metabolism;
Rat
- From:
Chinese Journal of Physical Medicine and Rehabilitation
2016;38(11):813-818
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect of cyclic tensile stress (CTS) on the metabolism inand apoptosis of rat chondrocytes.Methods Primary rat chondrocytes were cultured on a Bioflex plate for one day and then stretched cyclically for 24 hours at a frequency of 0.5 Hz using a Flexcell-5000T apparatus.The cells were divided into 5 groups according to their stretching ratio:0% (the control group),2%,6%,10% and 14%.After the stretching,Col Ⅱ,Aggrecan,MMP-13 and ADAMTS-5 mRNA were measured using qPCRs,and the NO and PGE2 levels were measured using ELISA kits.Moreover,TUNEL staining and Annexin V-FITC/PI were used to analyze the apoptosis of chondrocytes.Results Compared with the control group,the average levels of Col Ⅱ and Aggrecan mRNAdecreasedin 10% and 14% groups [(0.738±0.11) and (0.58±0.13),(0.75±0.11) and (0.55±0.09)].In those groups,the MMP-13 [(2.47±0.47) and (2.88±0.36)] and ADAMTS-5 mRNA level [(2.39±0.33) and (2.75±0.49)],the NO [(6.96±0.96) and (8.28±0.82)] and PGE2 level [(6.83±0.66) and (7.15±0.71)] had increased significantly.In the 6% group the average levels of Col Ⅱ(1.76±0.30) and Aggrecan mRNA (1.93±0.14)of 6% group were significantly higher than the control group,but the NO level of the former (3.07±0.20) was significantly lower than the control group (3.89 ± 0.33).The apoptosis rate of chondrocytesin 2% and 6% groups were (0.065±0.013) and (0.063 ± 0.147),without significant differences to that of the control group (0.045 ± 0.008).However,compared with the control group,apoptosis in the 10% and 14% groups [(0.135 ±0.026) and (0.184±0.020)] increased significantly.Conclusion The effect of cyclic tensile stress on chondrocyte metabolism and apoptosis was magnitude-dependent.Ten percent and 14% CTS can increase the catabolism and apoptosis of chondrocytes.Ten percent and 14% strain can increase the catabolism and apoptosis of chondrocytes.Cyclic 6% strain can increase the anabolism of chondrocytes,but 2% strain has no impact on metabolism or apoptosis.