Department of Biomolecular Pharmacology, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan.
Int J Mol Sci. 2019 Aug 2;20(15):3782. doi: 10.3390/ijms20153782.
Xeroderma is a frequent complication in diabetic patients. In this study, we investigated the mechanism underlying the onset of diabetic xeroderma, focusing on aquaporin-3 (AQP3), which plays an important role in water transport in the skin. Dermal water content in diabetic mice was significantly lower than that in control mice. The expression level of AQP3 in the skin was significantly lower in diabetic mice than in control mice. One week after streptozotocin (STZ) treatment, despite their increased blood glucose levels, mice showed no changes in the expression levels of AQP3, , , and () in the skin and 8-hydroxydeoxyguanosine (8-OHdG) in the urine. In contrast, two weeks after STZ treatment, mice showed increases in the blood glucose level, decreases in AQP3, , , and levels, and increases in the urinary levels of 8-OHdG. The results of this study suggest that skin AQP3 expression decreases in diabetes, which may limit water transport from the vessel side to the corneum side, causing dry skin. In addition, in diabetic mice, increased oxidative stress triggered decreases in the expression levels of and in the skin, thereby inhibiting the transcription of by , which resulted in decreased AQP3 expression.
糖尿病患者常发生 Xeroderma。在这项研究中，我们研究了糖尿病性 Xeroderma 的发病机制，重点关注在皮肤水转运中发挥重要作用的水通道蛋白-3（AQP3）。糖尿病小鼠的皮肤水分含量明显低于对照组小鼠。糖尿病小鼠皮肤中 AQP3 的表达水平明显低于对照组小鼠。尽管在链脲佐菌素（STZ）处理后 1 周，小鼠的血糖水平升高，但皮肤中 AQP3、AQP1、AQP7 和 （）的表达水平以及尿液中的 8-羟基脱氧鸟苷（8-OHdG）没有变化。相比之下，在 STZ 处理后 2 周，小鼠的血糖水平升高，AQP3、AQP1、AQP7 和 水平降低，尿液中 8-OHdG 水平升高。本研究结果表明，糖尿病患者皮肤 AQP3 表达减少，可能限制了从血管侧到角质层侧的水转运，导致皮肤干燥。此外，在糖尿病小鼠中，增加的氧化应激触发皮肤中 和 水平降低，从而抑制 对 的转录，导致 AQP3 表达减少。
