人脐带间充质干细胞条件培养基通过体内和体外 TLR4/NF-κB 信号通路减少炎症和上皮-间充质转化来减轻肾纤维化。

Human umbilical cord mesenchymal stem cell conditioned medium attenuates renal fibrosis by reducing inflammation and epithelial-to-mesenchymal transition via the TLR4/NF-κB signaling pathway in vivo and in vitro.

机构信息

Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China.

Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, Chongqing Key Laboratory of Pediatrics, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, 400014, China.

出版信息

Stem Cell Res Ther. 2018 Jan 12;9(1):7. doi: 10.1186/s13287-017-0760-6.

BACKGROUND

Renal fibrosis is characterized by infiltration of interstitial inflammatory cells and release of inflammatory mediators, activation and proliferation of fibroblasts, and deposition of excessive extracellular matrix (ECM). The aim of this study was to evaluate the effect of human umbilical cord-derived mesenchymal stem cell (hucMSC) conditioned medium (CM) on renal tubulointerstitial inflammation and fibrosis.

METHODS

Renal interstitial fibrosis was prepared in vivo using the unilateral ureteral obstruction (UUO). Rats were divided randomly into Sham group, Sham group with CM, UUO group, and UUO group with CM. The effect of hucMSC-CM on kidney injury induced by UUO was assessed by detecting kidney histopathology, serum creatinine (SCr), and blood urea nitrogen (BUN). The levels of TNF-α, IL-6, and IL-1β in serum and kidney tissues were detected by ELISA. The expression of proteins associated with fibrosis and renal inflammation was investigated using immunohistochemical staining and western blotting. The effects of hucMSC-CM on the TGF-β1-induced epithelial-mesenchymal transition (EMT) process and on inflammation in NRK-52E cells were investigated by immunofluorescent staining, ELISA, and western blotting.

RESULTS

hucMSC-CM reduced extracellular matrix deposition and inflammatory cell infiltration as well as release of inflammatory factors in UUO-induced renal fibrosis. Furthermore, hucMSC-CM markedly attenuated the EMT process and proinflammatory cytokines in rats with UUO and TGF-β1-induced NRK-52E cells. hucMSC-CM also inhibited the TLR4/NF-κB signaling pathway in vivo and in vitro.

CONCLUSIONS

Our results suggest that hucMSC-CM has protective effects against UUO-induced renal fibrosis and that hucMSC-CM exhibits its anti-inflammatory effects through inhibiting TLR4/NF-κB signaling pathway activation.

背景

肾纤维化的特征是间质炎症细胞浸润和炎症介质释放、成纤维细胞激活和增殖以及细胞外基质（ECM）过度沉积。本研究旨在评估人脐带间充质干细胞（hucMSC）条件培养基（CM）对肾小管间质炎症和纤维化的影响。

方法

采用单侧输尿管梗阻（UUO）法在体内制备肾间质纤维化。将大鼠随机分为假手术组、假手术组加 CM、UUO 组和 UUO 组加 CM。通过检测肾脏组织病理学、血清肌酐（SCr）和血尿素氮（BUN）来评估 hucMSC-CM 对 UUO 诱导的肾脏损伤的影响。采用 ELISA 法检测血清和肾组织中 TNF-α、IL-6 和 IL-1β的水平。采用免疫组化染色和 Western blot 法检测与纤维化和肾脏炎症相关的蛋白表达。通过免疫荧光染色、ELISA 和 Western blot 法研究 hucMSC-CM 对 TGF-β1 诱导的上皮间质转化（EMT）过程和 NRK-52E 细胞炎症的影响。

结果

hucMSC-CM 减少了 UUO 诱导的肾纤维化中外基质沉积和炎症细胞浸润以及炎症因子的释放。此外，hucMSC-CM 显著减轻了 UUO 大鼠和 TGF-β1 诱导的 NRK-52E 细胞中的 EMT 过程和促炎细胞因子。hucMSC-CM 还抑制了 TLR4/NF-κB 信号通路的体内和体外活性。