A polyphenol complex from Thymus vulgaris L. plants cultivated in the Campania Region (Italy): New perspectives against neuroblastoma

Abstract A thyme polyphenol extract (TPE) from Thymus vulgaris plants cultivated in the Campania Region (Italy) underwent qualitative and quantitative analyses using liquid chromatography–tandem mass spectrometry (LC–MS/MS) techniques and its effects were investigated on neuroblastoma cells. The extract, rich in rosmarinic acid and methoxylated flavones, inhibited mitochondrial redox activity and cell viability towards SH-SY5Y and SK-N-BE(2)-C cell lines at doses of 62.5 and 125 µg/mL. Cytotoxic TPE exposure resulted in an increase in intracellular reactive oxygen species (ROS) levels, and activation of caspases-8 and -3, consistent with our hypothesis that it possesses apoptosis-inducing properties. The occurrence of apoptosis was further established by attenuated total reflectance Fourier transform infrared (ATR FTIR) analysis: spectra from TPE-treated cells showed a significant decrease of nucleic acid/amide II ratio. The data obtained encourage further investigation and assessment of the efficacy of TPE in preclinical and clinical models to treat neuroblastoma, a major cause of mortality worldwide.