Objective: To investigate on the cytotoxicity and penetration enhancement effect of essential oils (EOs) from warming the interior medicinals (WIM) from Traditional Chinese Medicine (TCM).
Methods: EOs were extracted from WIM of Bichengqie (Litseae Fructus), Dingxiang (Flos Syzygii Aromatici), Huajiao (Pericarpium Zanthoxyli Bungeani), and Xiaohuixiang (Fructus Foeniculi) with warm nature, and Ganjiang (Rhizoma Zingiberis), Gaoliangjiang (Rhizoma Alpiniae Officinari), Rougui (Cortex Cinnamomi Cassiae), and Wuzhuyu (Fructus Evodiae Rutaecarpae) with hot nature, respectively. Their chemical compositions were analyzed by gas chromatography-mass spectrometry (GC-MS). The cytotoxicity of the extracted eight EOs on HaCaT cells was measured and compared. Moreover, analyses of cell cycle and cell apoptosis were performed to investigate the cytotoxic mechanism. The transdermal penetration enhancement effects of the extracted eight EOs on ibuprofen were further compared by the modified Franz diffusion cell method.
Results: The most abundant constituents in the extracted eight EOs were determined to be monoterpenes, especially oxygen-containing monoterpenes. The HaCaT cell cytotoxicity of EOs from WIM with hot nature were significantly (P = 0.020) higher than that with warm nature. Both ginger oil and zanthoxylum oil significantly induced G0/G1 phase arrestment in HaCaT cell cycle. For ginger oil from WIM with hot nature and zanthoxylum oil from WIM with warm nature, the main mechanisms of the cytotoxicity were found to be the induction of cellular necrosis and the cellular apoptosis, respectively. Furthermore, most of the tested EOs showed remarkable penetration enhancement activity on ibuprofen. However, no statistical significance (P = 0.18) was found between penetration enhancement activity of EOs from WIM with warm nature and EOs from WIM with hot nature.
Conclusion: With the enhanced penetration activity, the extracted EOs from the WIM demonstrated their significant effect of the cytotoxicity on the skin cells.
Keywords: Administration, oral; Liver; Scutellaria baicalensis; Toxicity tests, chronic.