The potential applications of low temperature plasma (LTP) in wound healing have aroused the concern of many researchers. In this study, an argon atmospheric pressure plasma jet was applied to generate LTP for treatment of murine fibroblast cell (L929) culturedin vitroto investigate the effect of NF-κB pathway on fibroblast proliferation. The results showed that, compared with the control, L929 cells treated with plasma for less than 20 s had significant increases of proliferation; the productions of intracellular ROS, O₂⁻and NO increased with prolongation of LTP treatment time; NF-κB pathway was activated by LTP in a proper dose range, and the expression of cyclinD1 in LTP-treated cells increased with the same trend as cell proliferation. After RNA interference to block p65 expression, with the same treatment time, RNAi-treated cells proliferated more slowly and expressed less cyclinD1 than normal cells. Furthermore, pretreatment with N-acetyl-L-cysteine (NAC) markedly prevented the plasma-induced changes in cells. In conclusion, the proliferation of L929 cells induced by LTP was closely related to NF-κB signaling pathway, which might be activated by appropriate level of intracellular ROS. These novel findings can provide some theoretical reference of LTP inducing cell proliferation and promoting wound healing.

Low temperature plasma (LTP) technology has shown an outstanding application value in the pharmaceutical filed in recent ten years. This paper reviews the research advances in LTP, including its effects on enhancing or inhibiting drug activity, its combined use with drugs to treat cancers, its effects on the improvement of drug delivery system, its use in preparation of new inactivated virus vaccines, its use with mass spectrometry for rapid detection of drug quality, and the anti-tumor and sterilization effects of plasma-activated liquids. The paper also analyzes the challenges of LTP in the pharmaceutical filed, hoping to promote related research.

An argon atmospheric pressure plasma jet was employed to treat L929 murine fibroblasts cultured in vitro. Experimental results showed that, compared with the control cells, the treatment of fibroblasts with 15 s of plasma led to a significant increase of cell viability and collagen synthesis, while the treatment of 25 s plasma resulted in a remarkable decrease. Exploration of related mechanisms suggested that cold plasma could up-regulate CyclinD1 gene expression and down-regulate p27 gene expression at a low dose, while it could down-regulate CyclinD1 expression and up-regulate p27 expression at a higher dose, thus altering the cell cycle progression, and then affecting cell viability and collagen synthesis of fibroblasts.

The potential antitumor application of low-temperature plasma (LTP) has attracted wide attention from researchers. The mechanism of plasma antitumor action may be related to LTP-induced reactive oxygen and nitrogen species. The aim of this study was to identify the apoptotic effects of plasma on melanoma cells (B16) in vivo and in vitro . For this purpose, a helium atmospheric-pressure plasma jet (APPJ) was used to generate the plasma-activated saline and medium (PAS and PAM). The PAS was injected subcutaneously to treat B16-tumor bearing mice in vivo and the PAM was used to treat B16 cells in vitro . Catalase (CAT) was added into the PAM to degrade H ₂ O ₂ as the intervention group. The tumor nodules’ weight, cryosections, B16 cell viability, apoptosis, DNA damage, p53 pathway-related protein and the concentration of H ₂ O ₂ in PAM were detected. The in vivo results showed that PAS could inhibit tumor growth and induce apoptosis. The in vitro results revealed the concentration of H ₂ O ₂ in the PAM increased as LTP treatment time was longer, while the cell viability decreased as APPJ irradiation time was increased. Flow cytometry results showed that, compared with the control group, all PAM treatment groups showed a higher apoptotic rate. A single cell gel assay and an 8-OHdG assay showed that the PAM could induce DNA damage. A western blotting assay indicated that the PAM could increase the expressions of p53, p53-induced gene 8 protein, PIG3, cytoplasmic cytochrome c, cleaved-caspase-9 and -3. However, CAT could alleviate all these changes effectively. These findings suggested that plasma exerted an apoptotic effect on B16 cells mainly by activating the p53/PIGs/caspase pathway.