Effects of propofol on proliferation and anti-apoptosis of neuroblastoma SH-SY5Y cell line: new insights into neuroprotection.

Recently, it has been suggested that anesthetic agents may have neuroprotective potency. The notion that anesthetic agents can offer neuroprotection remains controversial. Propofol, which is a short-acting intravenous anesthetic agent, may have potential as a neuroprotective agent. In this study, we tried to determine whether propofol affected the viability of human neuroblastoma SH-SY5Y cells by using the MTT assay. Surprisingly, our results showed that propofol at a dose of 1-10 μM could improve cell proliferation. However, at higher doses (200 μM), propofol appears to be cytotoxic. On the other hand, propofol could up-regulate the expression of key proteins involved in neuroprotection including B-cell lymphoma 2 at a dose range of 1-10 μM, activation of phospho-serine/threonine protein kinase at a dose range of 0.5-10 μM, and activation of phospho-extracellular signal-regulated kinases at a dose range of 5-10 μM. Similarly, we demonstrate that propofol (10 μM) could elevate protein levels of heat shock protein 90 and heat shock protein 70. Therefore, we choose to utilize a 10 μM concentration of propofol to assess neuroprotective activities in our studies. In the following experiments, we used dynorphin A to generate cytotoxic effects on SH-SY5Y cells. Our data indicate that propofol (10 μM) could inhibit the cytotoxicity in SH-SY5Y cells induced by dynorphin A. Furthermore, propofol (10 μM) could decrease the expression of the p-P38 protein as well. These data together suggest that propofol may have the potential to act as a neuroprotective agent against various neurologic diseases. However, further delineation of the precise neuroprotective effects of propofol will need to be examined.