Adipogenic and tenogenic differentiation of tendon-derived stem cells isolated from an animal model of chronic tendinopathy in vitro

Chen Hui; Lin Yu-cheng; Xu Hong-liang; Wang Chen; Rui Yun-feng

doi:10.3969/j.issn.2095-4344.2014.45.019

Abstract：BACKGROUND:Chronic tendinopathy is a tendon disorder extremely common in athletes and in the general population with repetitive strain injuries of tendons. The pathogenesis of tendinopathy remains unclear and hence treatment of tendinopathy is usual y pal iative. <br> OBJECTIVE:To investigate the of adipogenic and tenogenic ability of patel ar tendon-derived stem cel s isolated <br> from chronic tendinopathy and healthy rats in vitro. <br> METHODS:Tendon-derived stem cel s were isolated from patel ar tendons of chronic tendinopathy and healthy rats respectively. The tendon-derived stem cel s were cultured to the 3rd passage in complete culture medium, and cel morphology was observed. The cel s were divided into adipogenic induction group and control group. Cel s in the adipogenic induction group were cultured in adipogenic induction medium, while those in the control group cultured in complete culture medium. The ability of adipogenic differentiation between tendon-derived stem cel s isolated from the tendon of chronic tendinopathy and healthy rats in vitro was examined by oil red O staining and quantification assay. The mRNA expressions of C/EBPαand PPARγ2 were detected by real-time quantitative PCR. When 70%-80%cel s were confluent, the mRNA expressions of Col1a1, Scx, Tnmd and Dcn were also detected by real-time quantitative PCR. <br> RESULTS AND CONCLUSION:At the third passage, slender spindle-shaped cel s were seen in both two groups, but there was a little change in the cel morphology in the chronic tendinopathy group. Lipid droplets were formed after the cel s were cultured in adipogenic induction medium for 21 days. This was not observed in the control group. We observed more oil red O-positive oil droplets in tendon-derived stem cel s from the tendons of chronic tendinopathy rats than healthy rats. The difference between them was statistical y significant (P=0.004). The results of real-time quantitative PCR showed that the mRNA expressions of C/EBPαand PPARγ2 in the tendon-derived stem cel s from the tendons of chronic tendinopathy rats were significantly higher than those in tendon-derived stem cel s from the tendons of healthy rats (P=0.004);the mRNA expressions of Col1a1, Scx, Tnmd and Dcn in the tendon-derived stem cel s from the tendons of chronic tendinopathy rats were significantly lower than those in tendon-derived stem cel s from the tendons of healthy rats (P=0.009). In conclusion, tendon-derived stem cel s from chronic tendinopathy rats showed a higher ability of adipogenic differentiation, but a lower capacity of tenogenic differentiation compared to tendon-derived stem cel s from healthy rats, which might contribute to better understand the pathogenesis of tendinopathy.