HIPK2通过调控炎症及DNA损伤修复影响急性肾损伤进展及慢性化转归

Acute kidney injury（AKI) is a common clinical emergency，which could lead to acute renal failure (ARF), and even cause other organ failure，Also AKI is one of the most important causes of chronic kidney disease (CKD), inflammatory and DNA damage play an important role in the process of AKI. Homeodomain-interacting protein kinase 2(HIPK2) is a conserved serine/threonine nuclear kinase which could control expression and post transcriptional modification of many transcription factors mediating differentiation, apoptosis and inflammatory. HIPK2 up-regulate target genes of p53, the important effector proteins of DNA damage response(DDR) and NF-κB pathway, the important inflammatory signaling pathway. Previous research shows that HIPK2 could up-regulate taeget genes of NF-κB signaling pathway, And then regulate renal tubulointerstitial fibrosis. Our pre-experiment found that the expression of HIPK2 in AKI was closely related to the progression of AKI, suggesting that HIPK2 plays an important role in the progression and outcome of AKI. We hypothesized that HIPK2 could influence the progress and prognosis of chronic conversion of AKI through regulating NF-κB signaling pathway and activation of p53 . Here, we operated vivo and vitro experiments to explore the effect of HIPK2 and its possible mechanism in acute kidney injury，Which will provide an important theoretical basis for prevention and control of AKI.

急性肾损伤(AKI)不仅可以导致急性肾衰竭及远处器官衰竭，AKI也是慢性肾脏病重要原因之一，炎症和DNA损伤在AKI发病过程中起重要作用。同源结构域相互作用蛋白激酶 2 (HIPK2) 是一种定位在细胞核内，调节细胞增生、分化、凋亡和炎症的丝氨酸／苏氨酸激酶。HIPK2不仅是DNA损伤相关激酶p53的关键性上游蛋白激酶，还直接参与调控NF-κB通路，影响炎症反应。前期研究表明HIPK2可以通过调控NF-κB通路的活化而调控慢性肾脏病的进展。预实验通过构建急性肾损伤模型观察HIPK2在AKI中的表达，发现HIPK2的表达与AKI病情进展密切相关，推测HIPK2在AKI进展及转归中有重要调控作用。我们假设HIPK2可能通过调节NF-κB通路与活化p53影响AKI的进展及慢性化转归。本研究通过设计体内及体外实验，从多方面探讨HIPK2在AKI中的作用及其可能机制，为AKI的防治提供理论依据。

第一部分：探讨HIPK2在顺铂诱导的AKI及AKI-CKD模型中的作用及其可能机制.急性肾损伤(AKI)不仅可以导致急性肾衰竭及远处器官衰竭，AKI也是慢性肾脏病重要原因之一，炎症在AKI发病过程中起重要作用。同源结构域相互作用蛋白激酶2(HIPK2)是一种定位在细胞核内，调节细胞增生、分化、凋亡和炎症的丝氨酸／苏氨酸激酶。研究发现HIPK2可以直接参与调控NF-κB 信号通路，影响炎症反应。前期研究表明HIPK2可以通过调控NF-κB通路的活化而调控慢性肾脏病的进展。预实验通过构建急性肾损伤模型观察HIPK2在AKI中的表达，发现HIPK2的表达与AKI病情进展密切相关，推测HIPK2可能通过调控NF-κB 信号通路的活化影响AKI进展及AKI-CKD转归。本研究通过设计动物实验模型（AKI模型， AKI-CKD模型），通过病理染色，免疫荧光, Western blot及Real-time PCR等方法发现顺铂诱导的AKI组及AKI-CKD组，HIPK2及NF-κB 信号通路相关指标（p65， p-p65及炎症因子）的表达均明显升高。体外实验顺铂刺激小鼠肾小管上皮细胞（MCT）模型同样发现上述趋势，并且呈浓度及时间依赖性。体外实验转染HIPK2小干扰发现，干扰HIPK2的表达后，NF-κB相关通路蛋白及炎症指标的表达均相应减低，推测HIPK2可能通过调控NF-κB通路的活化影响AKI的进展及AKI-CKD转归。.第二部分：氯硝柳胺磷酸酯通过抑制Wnt/β-catenin 信号通路抑制肾脏组织纤维化 .肾脏纤维化是各种慢性肾脏病进展至ESRD的共同途径，目前还未发现抑制肾脏纤维化的特效药。氯硝柳胺为美国FDA已批准用药，既往用于肠道寄生虫感染，氯硝柳胺磷酸酯(phosphate niclosamide，P-NICLO)为该药的衍生物。本研究通过构建体内（UUO模型）及体外（TGF-β1体外刺激NRK-52E细胞导致细胞转分化）模型探讨氯硝柳胺磷酸酯（P-NICLO）抑制肾脏组织纤维化的作用及其可能机制。通过病理染色，Western blot及Real-time PCR等方法发现 P-NICLO可以明显抑制肾脏组织纤维化，模型组 Wnt/β-catenin 信号通路也被明显抑制，表明P-NICLO可能通过抑制Wnt/β-catenin 信号通路而抑制肾脏组织纤维化。