Proliferation-Related Activity in Endothelial Cells Is Enhanced by Micropower Plasma

Nonthermal plasma has received a lot of attention as a medical treatment technique in recent years. It can easily create various reactive chemical species (ROS) and is harmless to living body. Although plasma at gas-liquid interface has a potential for a biomedical application, the interactions between the gas-liquid plasma and living cells remain unclear. Here, we show characteristics of a micropower plasma with 0.018 W of the power input, generated at gas-liquid interface. We also provide the evidence of plasma-induced enhancement in proliferation activity of endothelial cells. The plasma produced H(2)O(2), HNO(2), and HNO(3) in phosphate buffered saline containing Mg(++) and Ca(++) (PBS(+)), and their concentration increased linearly during 600-second discharge. The value of pH in PBS(+) against the plasma discharge time was stable at about 7.0. Temperature in PBS(+) rose monotonically, and its rise was up to 0.8°C at the bottom of a cell-cultured dish by the plasma discharge for 600 s. Short-time treatment of the plasma enhanced proliferation activity of endothelial cells. In contrast, the treatment of H(2)O(2) does not enhance the cell proliferation. Thus, the ROS production and the nuclear factor-kappa B (NF-κB) activation due to the plasma treatment might be related to enhancement of the cell proliferation. Our results may potentially provide the basis for developing the biomedical applications using the gas-liquid plasma.