Tendon-bone junctions (TBJs) are frequently injured, especially in athletic settings. Healing of TBJ injuries is slow and is often repaired with scar tissue formation that compromises normal function. This study explored the feasibility of using kartogenin (KGN), a biocompound, to enhance the healing of injured TBJs. We first determined the effects of KGN on the proliferation and chondrogenic differentiation of rabbit bone marrow stromal cells (BMSCs) and patellar tendon stem/progenitor cells (PTSCs) in vitro. KGN enhanced cell proliferation in both cell types in a concentration-dependent manner and induced chondrogenic differentiation of stem cells, as demonstrated by high expression levels of chondrogenic markers aggrecan, collagen II and Sox-9. Besides, KGN induced the formation of cartilage-like tissues in cell cultures, as observed through the staining of abundant proteoglycans, collagen II and osteocalcin. When injected into intact rat patellar tendons in vivo, KGN induced cartilage-like tissue formation in the injected area. Similarly, when KGN was injected into experimentally injured rat Achilles TBJs, wound healing in the TBJs was enhanced, as evidenced by the formation of extensive cartilage-like tissues. These results suggest that KGN may be used as an effective cell-free clinical therapy to enhance the healing of injured TBJs.

中文翻译：

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Kartogenin诱导肌腱-骨连接处的软骨样组织形成。

肌腱-骨连接处（TBJ）经常受伤，特别是在运动环境中。TBJ损伤的愈合很慢，通常会通过疤痕组织形成修复，从而损害正常功能。这项研究探索了使用生物合成化合物kartogenin（KGN）增强受伤的TBJ愈合的可行性。我们首先确定了KGN对体外兔骨髓基质细胞（BMSCs）和tell腱干/祖细胞（PTSCs）增殖和软骨分化的影响。KGN以浓度依赖的方式增强了两种细胞类型中的细胞增殖，并诱导了干细胞的软骨形成分化，这由软骨形成标记物聚集蛋白聚糖，胶原蛋白II和Sox-9的高表达水平证明。此外，KGN还诱导了细胞培养中软骨样组织的形成，通过大量蛋白多糖，II型胶原和骨钙素的染色观察到。当体内注射到完整的大鼠pa腱中时，KGN会在注射区域诱导软骨样组织形成。同样，当将KGN注射到实验性受伤的大鼠跟腱TBJ中时，TBJ中的伤口愈合得到增强，这由广泛的软骨样组织形成证明。这些结果表明，KGN可以用作一种有效的无细胞临床疗法，以增强受损TBJ的愈合。如广泛的软骨样组织形成所证明。这些结果表明，KGN可以用作一种有效的无细胞临床疗法，以增强受损TBJ的愈合。如广泛的软骨样组织形成所证明。这些结果表明，KGN可以用作一种有效的无细胞临床疗法，以增强受损TBJ的愈合。