PVN adenovirus-siRNA injections silencing either NOX2 or NOX4 attenuate aldosterone/NaCl-induced hypertension in mice.
PVN adenovirus-siRNA injections silencing either NOX2 or NOX4 attenuate aldosterone/NaCl-induced hypertension in mice.
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DOI：
10.1152/ajpheart.00873.2011
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发表时间：
2012-02
期刊：
影响因子：
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通讯作者：
B. Xue;T. Beltz;Ralph F. Johnson;F. Guo;M. Hay;A. Johnson
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文献类型：
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作者：
B. Xue;T. Beltz;Ralph F. Johnson;F. Guo;M. Hay;A. Johnson
盐皮质激素过量通过激活NADPH氧化酶（NOX）增加超氧化物的产生，侧脑室注射NADPH氧化酶抑制剂可减轻醛固酮（Aldo）/盐诱导的高血压。据推测，脑中活性氧（ROS）的增加可能是高血压发生的关键机制。本研究探讨了NADPH氧化酶的脑区域特异性和NOX 2和NOX 4 NADPH氧化酶亚单位在下丘脑室旁核（PVN）在Aldo/salt诱导的高血压中的作用。使用PVN注射表达靶向N 0X 2（AdsiRNA-N 0X 2）或N 0X 4（AdsiRNA-N 0X 4）mRNA的小干扰（si）RNA的腺病毒载体来敲低N 0X 2和N 0X 4蛋白。3天后，通过渗透泵开始给予Aldo（0.2 mg·kg（-1）·day（-1）sc），并提供1% NaCl代替水。PVN注射AdsiRNA-NOX 2或AdsiRNA-NOX 4显著减弱Aldo/NaCl诱导的高血压的发展。在另一项研究中，与野生型对照相比，NOX 2（基因组）敲除小鼠中Aldo/盐诱导的高血压也显着减弱。当两项功能研究的动物接受神经节阻滞时，NOX 2和NOX 4敲除/敲除小鼠的血压下降幅度减小。对siRNA-NOX 2或siRNA-NOX 4注射小鼠的PVN的蛋白质印迹分析证实了NOX 2或NOX 4蛋白表达的显著降低。在培养的PVN神经元中，通过用siRNA-NOX 2或siRNA-NOX 4培养PVN细胞来沉默NOX 2或NOX 4蛋白的产生，减弱了Aldo诱导的ROS。这些数据表明，NOX 2和NOX 4在PVN有助于交感神经活动的升高和盐皮质激素过量诱导的高血压发生作用。
Mineralocorticoid excess increases superoxide production by activating NADPH oxidase (NOX), and intracerebroventricular infusions of NADPH oxidase inhibitors attenuate aldosterone (Aldo)/salt-induced hypertension. It has been hypothesized that increased reactive oxygen species (ROS) in the brain may be a key mechanism in the development of hypertension. The present study investigated the brain regional specificity of NADPH oxidase and the role of NOX2 and NOX4 NADPH oxidase subunits in the hypothalamic paraventricular nucleus (PVN) in Aldo/salt-induced hypertension. PVN injections of adenoviral vectors expressing small interfering (si)RNA targeting NOX2 (AdsiRNA-NOX2) or NOX4 (AdsiRNA-NOX4) mRNAs were used to knock down NOX2 and NOX4 proteins. Three days later, delivery of Aldo (0.2 mg·kg(-1)·day(-1) sc) via osmotic pump commenced and 1% NaCl was provided in place of water. PVN injections of either AdsiRNA-NOX2 or AdsiRNA-NOX4 significantly attenuated the development of Aldo/NaCl-induced hypertension. In an additional study, Aldo/salt-induced hypertension was also significantly attenuated in NOX2 (genomic) knockout mice compared with wild-type controls. When animals from both functional studies underwent ganglionic blockade, there was a reduced fall in blood pressure in the NOX2 and NOX4 knockdown/knockout mice. Western blot analyses of the PVN of siRNA-NOX2- or siRNA-NOX4-injected mice confirmed a marked reduction in the expression of NOX2 or NOX4 protein. In cultured PVN neurons, silencing either NOX2 or NOX4 protein production by culturing PVN cells with siRNA-NOX2 or siRNA-NOX4 attenuated Aldo-induced ROS. These data indicate that both NOX2 and NOX4 in the PVN contribute to elevated sympathetic activity and the hypertensivogenic actions induced by mineralocorticoid excess.