GADD45B mediates podocyte injury in zebrafish by activating the ROS-GADD45B-p38 pathway.
GADD45B mediates podocyte injury in zebrafish by activating the ROS-GADD45B-p38 pathway.
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GADD45B 通过激活 ROS-GADD45B-p38 通路介导斑马鱼足细胞损伤。
DOI：
10.1038/cddis.2015.300
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发表时间：
2016-01-21
影响因子：
9
通讯作者：
Liu Z
中科院分区：
文献类型：
--
作者：
Chen Z;Wan X;Hou Q;Shi S;Wang L;Chen P;Zhu X;Zeng C;Qin W;Zhou W;Liu Z
GADD45基因参与细胞周期停滞、细胞存活或细胞凋亡，其作用机制与细胞类型有关，且与细胞环境相关。GADD45基因家族成员在多种足细胞损伤模型中存在差异表达，但其在足细胞损伤中的作用尚不清楚。利用我们先前建立的斑马鱼体内诱导足细胞损伤的模型，我们发现斑马鱼gadd45b的同源基因是在诱导足细胞损伤的基础上诱导的。斑马鱼gadd45b的足细胞特异性过表达加剧了浮肿、蛋白尿和足突的消失，而在斑马鱼幼体中，通过吗啉寡聚糖敲除gadd45b可以缓解足细胞损伤。然后，我们通过体外足细胞培养来探讨GADD45B诱导在足细胞损伤中的作用。我们证实GADD45B在培养的人足细胞损伤早期显著上调，GADD45B过表达可加重转化生长因子-β和嘌呤霉素氨基核苷(PAN)诱导的足细胞凋亡，而shRNA介导的GADD45B基因敲除可减轻GADD45B的表达。我们还发现，ROS抑制剂NAC抑制PAN诱导的足细胞GADD45B表达和随后激活的p38MAPK通路，抑制GADD45B抑制PAN诱导的p38MAPK激活。综上所述，我们的研究结果表明GADD45B在足细胞损伤中具有重要作用，并可能成为肾小球疾病中足细胞损伤的治疗靶点。
GADD45 gene has been implicated in cell cycle arrest, cell survival or apoptosis in a cell type specific and context-dependent manner. Members of GADD45 gene family have been found differentially expressed in several podocyte injury models, but their roles in podocytes are unclear. Using an in vivo zebrafish model of inducible podocyte injury that we have previously established, we found that zebrafish orthologs of gadd45b were induced upon the induction of podocyte injury. Podocyte-specific overexpression of zebrafish gadd45b exacerbated edema, proteinuria and foot-process effacement, whereas knockdown of gadd45b by morpholino-oligos in zebrafish larvae ameliorated podocyte injury. We then explored the role of GADD45B induction in podocyte injury using in vitro podocyte culture. We confirmed that GADD45B was significantly upregulated during the early phase of podocyte injury in cultured human podocytes and that podocyte apoptosis induced by TGF-β and puromycin aminonucleoside (PAN) was aggravated by GADD45B overexpression but ameliorated by shRNA-mediated GADD45B knockdown. We also showed that ROS inhibitor NAC suppressed PAN-induced GADD45B expression and subsequent activation of p38 MAPK pathway in podocytes and that inhibition of GADD45B diminished PAN-induced p38 MAPK activation. Taken together, our findings demonstrated that GADD45B has an important role in podocyte injury and may be a therapeutic target for the management of podocyte injury in glomerular diseases.