Zanthoxylum bungeanum essential oil induces apoptosis of HaCaT human keratinocytes.

Ethnopharmacological Relevance: Zanthoxylum bungeanum (ZB), a Chinese herb medicine, has been shown to possess a wide range of biological activities including anti-tumor, anti-inflammatory, and anti-microbial activity and has long been used to treat a variety of skin diseases including psoriasis. However, the underlying mechanism of action has not been systematically elucidated.

Aim Of The Study: to analyze the chemical composition of the hydro-distilled Zanthoxylum bungeanum essential oil (ZBEO), and to investigate its anti-proliferative activity on HaCaT cells as well as the underlying anti-psoriasis mechanisms.

Materials And Methods: The chemical composition of ZBEO was analyzed with gas chromatography coupled to mass spectrometry (GC-MS). HaCaT cells was exposed to different dose of ZBEO added in medium prior to morphologic features analysis as well as cell cycle arrest examination with Flow cytometry. Western blot analysis was employed to estimate the expression level of proteins including caspase-8/9/3, PARP, Bax and Bcl-2.

Results: Thirty-nine compounds of the ZBEO were identified GC-MS. ZBEO-treated HaCaT cells showed typical apoptotic morphologic features by DAPI staining assay. The ZBEO significantly inhibited proliferation of HaCaT cells in a dose- and time-dependent manner and induced S phase arrest apoptosis in HaCaT cells. Furthermore, western blot analysis revealed that the ZBEO increased expression of cleaved caspase-8/9/3, PARP, and Bax, decreased Bcl-2 levels.

Conclusion: ZBEO inhibits the proliferation of HaCaT cells, resulting from the induction of cellular apoptosis through both intrinsic and extrinsic pathways. ZBEO is a potential candidate that may be considered for development into an anti-psoriasis drug.