Zhang Chong, Liu Yu-Jie
Associated Professor, Department of Orthopaedic Surgery, Traditional Chinese Medicine Hospital, Hebei Province, China. Aquisition of data, manuscript writing.
MD, Professor, Department of Orthopaedic Surgery, Chinese PLA General Hospital, Beijing, China. Design, intellectual and scientific content of the study; critical revision.
Acta Cir Bras. 2017 Dec;32(12):1045-1055. doi: 10.1590/s0102-865020170120000006.
To evaluate the effect of transforming growth factor β1 (TGF-β1) on tendon-to-bone reconstruction of rotator cuff tears.
Seventy-two rat supraspinatus tendons were transected and reconstructed in situ. At 8 and 16 weeks, specimens of three groups; that is control, L-dose (low dose), and H-dose (high dose) were harvested and underwent a biomechanical test to evaluate the maximum load and stiffness values. Histology sections of the tendon-to-bone interface were identified by hematoxylin-eosin or Masson trichrome stain. Collagen type III was observed by picric acid sirius red staining under polarized light. The level of insulin-like growth factor 1 (IGF-1) and vascular endothelial growth factor (VEGF) was measured by the enzyme-linked immunosorbent assay (ELISA) method.
Collagen type III of the H-dose group had a significant difference in histology structure compared with the L-dose group (P<0.05). The maximum load and stiffness decreased significantly in the control group compared with the values of the L-dose and H-dose groups. The stiffness among the three groups differed significantly at the same postoperative time (P<0.05). Interestingly, progressive reestablishment of collagen type III affected tendon-to-bone healing significantly in the later stages.
The H-dose was associated with an increased collagen type III morphology stimulated by TGF-β1.
评估转化生长因子β1（TGF-β1）对肩袖撕裂肌腱-骨重建的影响。
将72只大鼠的冈上肌腱切断并原位重建。在8周和16周时，采集三组（即对照组、低剂量组和高剂量组）的标本，进行生物力学测试以评估最大负荷和刚度值。通过苏木精-伊红或Masson三色染色对肌腱-骨界面的组织学切片进行鉴定。在偏光下用苦味酸天狼星红染色观察III型胶原蛋白。采用酶联免疫吸附测定（ELISA）法测量胰岛素样生长因子1（IGF-1）和血管内皮生长因子（VEGF）的水平。
高剂量组的III型胶原蛋白在组织结构上与低剂量组相比有显著差异（P<0.05）。与低剂量组和高剂量组相比，对照组的最大负荷和刚度显著降低。三组在术后同一时间的刚度差异显著（P<0.05）。有趣的是，III型胶原蛋白的逐步重建在后期对肌腱-骨愈合有显著影响。
高剂量与TGF-β1刺激的III型胶原蛋白形态增加有关。
