Sasanquasaponin from Camellia oleifera Abel Exerts an Anti-Inflammatory Effect in RAW 264.7 Cells via Inhibition of the NF-κB/MAPK Signaling Pathways

Sasanquasaponin (SQS), a secondary metabolite that is derived from Camellia seeds, reportedly possesses notable biological properties. However, the anti-inflammatory effects of SQS and its underlying mechanisms remain poorly explored. Herein, we aimed to investigate the anti-inflammatory properties of SQS against lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells, focusing on the nuclear factor-κB (NF-κB) and MAPK signaling pathways. SQS was isolated using a deep eutectic solvent and D101 macroporous adsorption resin and analyzed using high-performance liquid chromatography. The viability of LPS-stimulated RAW264.7 was assessed using the CCK-8 assay. The presence of reactive oxygen species (ROS) was evaluated using 2',7'-dichlorofluorescein-diacetate. The expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) were detected using reverse transcription-quantitative PCR and ELISA. Western blot was performed to analyze the protein expression of LPS-induced RAW264.7 cells. Herein, SQS exhibited anti-inflammatory activity: 30 μg/mL of SQS significantly reduced ROS generation, inhibited the LPS-induced expression of iNOS and COX-2, and attenuated the production of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. The anti-inflammatory activity was potentially mediated by inhibiting the phosphorylation of IκBα and p65 in the NF-κB signaling pathway and the phosphorylation of ERK and JNK in the MAPK signaling pathway. Accordingly, SQS could inhibit inflammation in LPS-induced RAW264.7 cells by suppressing the NF-κB and MAPK signaling pathways. This study demonstrated the potential application of SQS as an anti-inflammatory agent.

[Determination of 18 polychlorinated biphenyls in camellia seeds by multiple vortex and gas chromatography-triple quadrupole mass spectrometry]

A method based on the cleaning effects of different sorbents and gas chromatography-triple quadrupole mass spectrometry (GC-QQQ-MS/MS) was developed for the determination of 18 polychlorinated biphenyls (PCBs) in camellia seeds. The camellia seeds were extracted with acetonitrile, salted out with sodium chloride, then cleaned-up by QuEChERS with anhydrous MgSO₄, C18, primary secondary amine (PSA), and multi walled carbon nanotubes (NANO) using multiple vortex after the centrifugal separation, and finally analyzed by GC-QQQ-MS/MS in multiple reaction monitoring mode via positive electrospray ionization. All the 18 PCBs could be completely separated with an excellent linear relationship. The limits of detection for the 18 PCBs were 5 μg/kg. For all the samples, the mean spiked recoveries was 109.2% with relative standard deviations (RSDs) of 2.9%-6.2% (n=3). The extraction, purification and analytical methods were developed and assessed. The method was successfully applied to the 48 samples from three main producing provinces of camellia seeds. All the 18 PCBs were not detected from the 48 samples.