参附注射液对早期脓毒症大鼠TIMP-3表达及毛细血管通透性的影响

Sepsis-induced degradation of glycocalyx leads to capillary hyperpermeability, which result in loss of effective circulating volume, tissue hypoperfusion, edema and hypoxia, accelerating progress in sepsis. Degradation of glycocalyx is directly related to overexpression of MMPs, while TIMP-3, an intrinsic inhibitor of MMPs, can reduce degradation of glycocalyx. Shenfu Injection was found to improve tissue perfusion, increase preload, decrease capillary permeability, down-regulate serum MMP-1 and Syndecan-1 in previous studies, illustrating that Shenfu Injection suppress degradation of glycocalyx in sepsis. We propose a hypothesis that Shenfu Injection can inhibit degradation of glycocalyx, alleviate capillary hyperpermeability, block the progress of sepsis by means of up-regulating expression of TIMP-3 and reducing the secretion of MMPs. In order to verify the hypothesis, we treat early sepsis rats with Shenfu injection and measure TIMP-3, MMPs, composition of glycocalyx and capillary permeability. Then we reversely prove the hypothesis applying gene knockout technology in order to explain the action mechanism of Shenfu Injection. This research will provide theoretical support for clinical application of Shenfu Injection and lay experimental foundation for further study on mechanism of intracellular pathways.

脓毒症诱导的内皮多糖包被降解可导致毛细血管通透性增加，进而引发有效循环血量减少、组织低灌注、水肿、缺氧，加速脓毒症进展；多糖包被的降解与MMPs过表达直接相关，TIMP-3作为体内主要的MMPs抑制剂可减少多糖包被的降解。前期研究发现参附注射液可改善脓毒症的组织灌注，增加前负荷，降低血管通透性，并可下调血清MMP-1和多糖包被组分Syndecan-1水平；表明参附注射液可抑制多糖包被的降解。在此基础上我们提出假说：参附注射液通过上调TIMP-3表达减少MMPs的分泌，抑制多糖包被的降解，降低血管通透性，进而阻断脓毒症的进展。为验证该假说，本研究应用参附注射液治疗早期脓毒症大鼠，监测TIMP-3——MMPs——多糖包被组分——毛细血管通透性变化的关系，并应用TIMP-3基因敲除技术进行反证，以阐释参附注射液的作用机制，为参附注射液的临床应用提供理论支持，并为细胞内通路机制的研究奠定实验基础。

脓毒症诱导的内皮多糖包被降解可导致毛细血管通透性增加，进而引发有效循环血量减少、组织低灌注、水肿、缺氧，加速脓毒症进展；多糖包被的降解与MMPs过表达直接相关，TIMP-3为体内主要的MMPs抑制剂，可减少多糖包被的降解。前期研究发现参附注射液可改善脓毒症的组织灌注，增加前负荷，降低血管通透性，并可下调血清MMP-1和多糖包被组分Syndecan-1水平；表明参附注射液可抑制多糖包被的降解。在此基础上我们提出假说：参附注射液通过上调TIMP-3表达减少MMPs的分泌，抑制多糖包被的降解，降低血管通透性，进而阻断脓毒症的进展。为验证该假说，本研究应用参附注射液治疗早期脓毒症大鼠，观察动物肺血管通透性、血清TIMP-3、MMPs、多糖包被组分水平、主动脉多糖包被组分水平，并应用基因敲除技术进行反证，阐释参附注射液治疗脓毒症的机制。.研究发现肺毛细血管通透性比较：脓毒症组＞参附低剂量组＞参附高剂量＞对照组；血清多糖包被组分比较：脓毒症组＞参附低剂量组＞参附高剂量＞对照组；血清TIMP-3水平：参附高剂量＞参附低剂量组＞脓毒症组＞对照组；血清MMPs水平：脓毒症组＞参附低剂量组＞参附高剂量＞对照组；主动脉多糖包被组分：对照组＞参附高剂量＞参附低剂量组＞脓毒症组。与参附组相比，基因敲除组大鼠血清多糖包被组分显著升高，主动脉多糖包被组分显著降低，血清MMPs水平显著升高。.研究表明，参附注射液可通过上调TIMP-3水平，降低MMPs表达，减轻内皮多糖包被的降解，降低血管通透性。本研究部分阐释了参附注射液治疗脓毒症的作用机制。