Nakajima Ai, Tsuji Mayumi, Inagaki Manami, Tamura Yurie, Kato Masumi, Niiya Akifumi, Usui Yuki, Oguchi Katsuji
Department of Pharmacology, School of Medicine, Showa University, Hatanodai 1-5-8, Shinagawa-ku, Tokyo 142-8555, Japan.
Department of Pharmacology, School of Medicine, Showa University, Hatanodai 1-5-8, Shinagawa-ku, Tokyo 142-8555, Japan.
Eur J Pharmacol. 2014 Feb 15;725:47-54. doi: 10.1016/j.ejphar.2014.01.003. Epub 2014 Jan 17.
Anesthetic treatment has been associated with widespread apoptotic neurodegeneration in the neonatal rodent brain. It has recently been suggested that propofol, a short-acting intravenous anesthetic agent, may have a potential as a neuroprotective agent. An apoptotic pathway mediated through endoplasmic reticulum (ER) stress has been attracting attention. ER stress is associated with accumulation of unfolded or misfolded proteins in ER, and ER stress-induced apoptosis is implicated in a wide range of diseases, including ischemia/reperfusion injury, neurodegeneration, and diabetes. We investigated whether thapsigargin-induced ER stress is prevented by propofol in human neuroblastoma SH-SY5Y cells. SH-SY5Y cells were pretreated with various concentrations of propofol (1-10 μM) for 3h before co-treatment with 0.5 μM thapsigargin and propofol for 20 h. Levels of ssDNA, specific evidence of apoptosis, and biomarkers of ER stress (mRNA expression of Chop and sXbp-1) were determined. We also assayed calpain and caspase-4 activities and intracellular Ca(2+) ([Ca(2+)]i) levels. Thapsigargin-induced increases in ssDNA levels, expressions of ER stress biomarkers, activities of caspase-4 and calpain, and level of [Ca(2+)]i were suppressed by co-incubation with propofol. Our data indicate the possibility that propofol inhibits the Ca(2+) release from ER at clinically employed dose levels. These results demonstrate that propofol suppresses the ER stress-induced apoptosis in this cell system, and may have the neuroprotective potency. It may also be a promising agent for preventing damage from cerebral ischemia or edema.
麻醉处理与新生啮齿动物脑内广泛的凋亡性神经退行性变有关。最近有研究表明，短效静脉麻醉剂丙泊酚可能具有神经保护剂的潜力。一种通过内质网（ER）应激介导的凋亡途径一直备受关注。ER应激与内质网中未折叠或错误折叠蛋白质的积累有关，ER应激诱导的凋亡与多种疾病有关，包括缺血/再灌注损伤、神经退行性变和糖尿病。我们研究了丙泊酚是否能在人神经母细胞瘤SH-SY5Y细胞中预防毒胡萝卜素诱导的ER应激。在与0.5μM毒胡萝卜素和丙泊酚共同处理20小时之前，将SH-SY5Y细胞用不同浓度的丙泊酚（1-10μM）预处理3小时。测定了单链DNA水平、凋亡的特异性证据以及ER应激的生物标志物（Chop和sXbp-1的mRNA表达）。我们还检测了钙蛋白酶和半胱天冬酶-4的活性以及细胞内Ca(2+)（[Ca(2+)]i）水平。与丙泊酚共同孵育可抑制毒胡萝卜素诱导的单链DNA水平升高、ER应激生物标志物的表达、半胱天冬酶-4和钙蛋白酶的活性以及[Ca(2+)]i水平。我们的数据表明，丙泊酚在临床应用剂量水平上可能抑制内质网释放Ca(2+)。这些结果表明，丙泊酚在该细胞系统中可抑制ER应激诱导的凋亡，可能具有神经保护作用。它也可能是预防脑缺血或水肿损伤的有前景的药物。
