Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Takara-machi 13-1, Kanazawa, Ishikawa, 920-8640, Japan.
Medical Research Training Program, School of Medicine, Kanazawa University, Kanazawa, Ishikawa, 920-8640, Japan.
Sci Rep. 2021 May 18;11(1):10540. doi: 10.1038/s41598-021-89997-5.
Aquaporin-4 (AQP4) is a predominant water channel expressed in astrocytes in the mammalian brain. AQP4 is crucial for the regulation of homeostatic water movement across the blood-brain barrier (BBB). Although the molecular mechanisms regulating AQP4 levels in the cerebral cortex under pathological conditions have been intensively investigated, those under normal physiological conditions are not fully understood. Here we demonstrate that AQP4 is selectively expressed in astrocytes in the mouse cerebral cortex during development. BMP signaling was preferentially activated in AQP4-positive astrocytes. Furthermore, activation of BMP signaling by in utero electroporation markedly increased AQP4 levels in the cerebral cortex, and inhibition of BMP signaling strongly suppressed them. These results indicate that BMP signaling alters AQP4 levels in the mouse cerebral cortex during development.
水通道蛋白 4（AQP4）是哺乳动物大脑中星形胶质细胞表达的主要水通道。AQP4 对于调节血脑屏障（BBB）内的稳态水运动至关重要。尽管已经深入研究了调节病理性大脑皮层中 AQP4 水平的分子机制，但对正常生理条件下的机制仍不完全了解。在这里，我们证明 AQP4 在发育过程中选择性地在小鼠大脑皮层的星形胶质细胞中表达。BMP 信号在 AQP4 阳性星形胶质细胞中优先被激活。此外，通过宫内电穿孔激活 BMP 信号可显著增加大脑皮层中的 AQP4 水平，而抑制 BMP 信号则强烈抑制 AQP4 水平。这些结果表明，BMP 信号在发育过程中改变了小鼠大脑皮层中的 AQP4 水平。
