Blockade of Orai1 Store-Operated Calcium Entry Protects against Renal Fibrosis
Blockade of Orai1 Store-Operated Calcium Entry Protects against Renal Fibrosis
复制标题
阻断 Orai1 商店运营的钙进入可预防肾纤维化
DOI：
10.1681/asn.2015080889
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发表时间：
2016-10-01
影响因子：
13.6
通讯作者：
Zhou, Jiaguo
中科院分区：
文献类型：
--
作者：
Mai, Xiaoyi;Shang, Jinyan;Zhou, Jiaguo
有证据支持Ca2+释放激活的Ca2+通道蛋白1 （Orai1）介导的Ca2+进入在肾纤维化的发展中发挥重要作用，肾纤维化是CKDs导致ESRD的常见病理特征，但其分子机制尚不清楚。我们研究了Orai1钙通道在高脂饮食和单侧输尿管梗阻致肾纤维化中的作用。与未纤维化的小鼠肾脏相比，纤维化小鼠肾脏的Orai1蛋白表达水平更高。在体内用携带Orai1短发夹RNA的腺病毒敲低Orai1或用SKF96365抑制Orai1可显著预防高脂饮食的ApoE（-/-）小鼠肾皮质和单侧输尿管梗阻小鼠肾中纤维连接蛋白、α -平滑肌肌动蛋白和tgf - β 1的蛋白表达。与肾小球微小病变患者的肾活检标本相比，纤维化肾病患者的肾活检标本中Orai1的表达水平较高。在培养的人近端小管上皮细胞（HK2）中，用腺病毒-Orai1短发卡RNA敲低Orai1 Ca2+通道可显著抑制tgf - β 1诱导的细胞内Ca2+内流和smad2/3的磷酸化。在HK2细胞中敲低或阻断Orai1 Ca2+通道也可以阻止tgf - β 1诱导的上皮到间质转化。总之，阻断Orai1 Ca2+通道可能通过抑制smad2/3磷酸化和tgf - β 1诱导的上皮到间质转化来阻止小鼠肾纤维化的进展。这些结果表明Orai1 Ca2+通道是抗肾纤维化的潜在治疗靶点。
Evidence supports an important role of Ca2+ release-activated Ca2+ channel protein 1 (Orai1)-mediated Ca2+ entry in the development of renal fibrosis, a common pathologic feature of CKDs that lead to ESRD, but the molecular mechanisms remain unclear. We determined the role of Orai1 calcium channel in renal fibrosis induced by high-fat diet and by unilateral ureteral obstruction. Mouse kidneys with fibrosis had higher levels of Orai1 protein expression than did kidneys without fibrosis. In vivo knockdown of Orai1 with adenovirus harboring Orai1-short hairpin RNA or inhibition of Orai1 with SKF96365 dramatically prevented renal fibrosis and significantly decreased protein expression of fibronectin, alpha-smooth muscle actin, and TGF-beta 1 in the kidney cortex of ApoE(-/-) mice on a high-fat diet and in the obstructed kidneys of mice with unilateral ureteral obstruction. Compared with kidney biopsy specimens of patients with glomerular minimal change disease, those of patients with fibrotic nephropathy had higher expression levels of Orai1. In cultured human proximal tubule epithelial cells (HK2), knockdown of Orai1 Ca2+ channel with adenovirus-Orai1-short hairpin RNA markedly inhibited TGF-beta 1-induced intracellular Ca2+ influx and phosphorylation of smad2/3. Knockdown or blockade of the Orai1 Ca2+ channel in HK2 cells also prevented epithelial-to-mesenchymal transition induced by TGF-beta 1. In conclusion, blockade of the Orai1 Ca2+ channel prevented progression of renal fibrosis in mice, likely by suppressing smad2/3 phosphorylation and TGF-beta 1-induced epithelial-to-mesenchymal transition. These results render the Orai1 Ca2+ channel a potential therapeutic target against renal fibrosis.