从血管内皮生长因子及其受体表达研究局灶硬化性肾炎蛋白尿的机制和艾灸的活血通络作用

Proteinuria is an independent risk factor for progressive kidney disease.Currently，clinicians put more focus on TCM syndrome distribution. External treatment on proteinuria is seldom to take actively as well as its research on mechanism. there are many researches on the collateral disease theory to proteinuria. The major point of this view suggest that glomerular filtration barrier (GFB) injured and tubulointerstitial fibrosis due to the statement of blood stasis in collateral vessels of kidney.Vascular endothelial growth factor (VEGF) maintains GFB functional integrity by inducing vascular endothelial differentiation and multi- fenestrae structure formulation, and intervents to the progress of tubulointerstitial fibrosis by inhibiting TGF-β1-induced epithelial-myofibroblast transition(EMT). Above all, we suggest that moxibustion adjust the statement of blood stasis in collateral vessels of kidney by activating blood circulation and freed the collateral vessels, so as to improve the glomerular filtration rate and tubulointerstitial fibrosis.The study chooses FSGS rat models as the method to observe the influence of moxibustion in different time and methods to renal pathological changes in the structure and cytokines, such as VEGF,VEGFR-2,TGF-β1,HGF,AngⅡ,AT1R,ET,NO,α-SMA,FN and Col-I. We try to explain the mechanism of proteinuria on FSGS and the effect of moxibustion activating blood circulation and freed the collateral vessels which related to VEGF regulating GFB and inhibiting EMT, so as to privide a clinical theoretical basis of moxibustion intervention to proteinuria on kidney disease.

蛋白尿是肾病恶化进展的独立危险因素，目前临床多以辨证论治为主，外治法挖掘及深入的机制研究尚不多见。"蛋白尿从络病论治"理论认为,肾络郁滞致病与肾小球滤过屏障（GFB）损伤及肾纤维化形成相关。血管内皮生长因子（VEGF）通过诱导血管内皮分化及多窗孔结构的形成维持GFB功能完整性；并通过抑制TGF-β1诱导肾小管上皮细胞-间充质转化（EMT）干预肾纤维化进程。据此提出假说，灸法活血通络调整肾络郁滞状态以改善肾小球滤过功能和抑制肾纤维化。本课题以局灶硬化性肾炎（FSGS）模型大鼠为研究对象，以科素亚作为对照，通过观察不同灸时灸法对FSGS模型大鼠肾脏病理组织结构变化及VEGF、VEGFR-2、TGF-β1、HGF、AngⅡ、ET、NO、α-SMA等因子表达的影响，从VEGF调节GFB、抑制EMT角度研究FSGS蛋白尿机制和艾灸的活血通络作用，以期为临床应用外治灸法治疗肾病蛋白尿提供部分理论依据

蛋白尿是肾病恶化进展的独立危险因素。“蛋白尿从络病论治”理论认为肾络郁滞致病与肾小球滤过屏障（GFB）损伤及肾纤维化形成相关。血管内皮生长因子（VEGF）通过诱导血管内皮分化及多窗孔结构的形成维持GFB功能完整性；并通过抑制TGF-β1诱导肾小管上皮细胞-间充质转化（EMT）干预肾纤维化进程。目前蛋白尿的临床治疗多以辨证论治为主，外治法挖掘及深入的机制研究尚不多见。基于上述的络病理论，本课题以局灶节段性肾小球硬化（FSGS）模型大鼠为研究对象，以氯沙坦作为对照，通过观察不同灸时灸法对FSGS模型大鼠肾组织病理结构变化及VEGF、VEGFR-2、TGF-β、HGF、AngⅡ、ET、NO、α-SMA等因子表达的影响，从VEGF调节GFB、抑制EMT角度研究FSGS蛋白尿机制和艾灸的活血通络作用。研究结果显示：与模型组比较，氯沙坦组、肾俞长时组和膈俞长时组大鼠血肌酐、血尿素氮、尿酸、尿蛋白均有不同程度降低（P＜0.05）；肾组织α-SMA、Col-I、FN、TGF-β、HGF、ET-1、AngII、AT1R、VEGF、VEGFR-2表达降低（P＜0.05）；NO含量升高（P＜0.05）；肾组织Podocin、Nephrin、CD2AP及其相关mRNA表达增强（P＜0.05）；肾小球硬化指数降低（P＜0.01），肾小球毛细血管丛管腔开放直径、毛细血管襻横截面积显著增大（P＜0.01），系膜基质相对面积减小（P＜0.01）。同一腧穴灸法组内比较，灸法长时组各项指标的改善相对于灸法短时组更具优势。研究结果论证了艾灸疗法可以改善FSGS模型大鼠的尿蛋白和肾功能；适当地延长艾灸时间保证灸量，可能会达到更好的治疗效果；艾灸活血化瘀、温经通络的特点可以调整肾络郁滞状态，改善FSGS模型大鼠的肾脏病理；其治疗效应可能是通过影响VEGF及其受体的表达，从而减轻足细胞损伤、抑制肾间质纤维化，进而改善肾小球硬化实现的；肾俞与膈俞两腧穴艾灸治疗组间的比较尚未见明显差异；穴位本身的特异性作用有待今后进一步研究。传统的外治灸法基于经络理论对机体的不同状态起着双向的良性调整作用，具有调和气血、疏经通络、扶正祛邪的功效，这与化瘀通络治疗蛋白尿的络病学说一致。可作为中医药治疗肾病蛋白尿、保护肾功能的新的切入点，为临床应用外治灸法治疗肾病蛋白尿提供部分理论依据。