亚硝基谷胱甘肽通过影响IL-1β/凝血酶/αC多聚体的调控轴对骨延迟愈合的作用及机制研究

骨创伤发病率和致残率高，骨延迟愈合是主要并发症之一，血凝块纤维结构延迟降解是其重要原因。申请人前期发现骨延迟愈合模型中血凝块主要由致密的细纤维组成，且IL-1β有更高浓度表达；并发现高浓度的IL-1β能刺激血小板生成过量的凝血酶，从而形成致密的、难于降解的细纤维凝块是诱发骨延迟愈合的重要原因。然而，调控IL-1β的表达并改变血凝块的纤维结构能否加速骨延迟愈合的早期愈合尚不清楚。本项目拟构建大鼠的骨延迟愈合模型，采用能影响人血浆中纤维结构的抗凝剂亚硝基谷胱甘肽（S-nitrosoglutathione, GSNO）干预，明确其对骨延迟愈合的影响；并通过血栓动力学、生物力学、纤维溶解等体外实验，探明GSNO是否调控IL-1β/凝血酶/αC多聚体这一通路发挥作用的分子机制，为促进骨延迟愈合的早期愈合提供新的思路和实验依据。

Delayed bone healing, especially if caused by traumatic injuries representing high incidence and disability, can be attributed to prolonged fibrinolysis arising from alteration of hematoma structure. Our preliminary studies showed that initial differences in hematoma structures, triggered by the effects of proinflammatory cytokine interlueukin-1 beta (IL-1β), between the normal compared the delayed bone defects signify the actual onset of the different healing pathways, determining the optimal recapitulation of bone healing. Furthermore, it has been found that the supra-physiological levels of thrombin, released from the degranulated platelets at the higher concentration of IL-1β, can enhance the formation of a dense clot with thinner fibers that resist timely fibrinolysis. However, there are few if any studies that have considered the manipulation of IL-1β and hematoma architectures on delayed bone healing. Following up from these findings, in this project we will investigate the influence of anti-coagulant s-nitrosoglutathione (GSNO) on de novo bone formation in rat delayed bone healing defects using morphological evaluation, radiographic analysis, and histological staining. Also, the effects of GSNO, on fibrin clot kinetics, rigidity, and fibrinolysis in blood clots, will be assessed by thromboelastography, compression, and clot lysis assays. Ultimately, the mechanisms governing the impact of GSNO on IL-1β/thrombin/αC polymers during fibrin polymerization will be exploited. The significance of this project may provide new insights into how to quicken delayed bone healing by modulating the in-situ blood clots.