The hPDLFs were extracted and cultured in vitro， and they were identified by immunohistochemical staining. The hPDLFs were divided into control group （0 mg·L^－1 P.g-LPS）， 1 mg·L^－1 P.g-LPS group， and 10 mg·L^－1 P.g-LPS group； the cells were treated for 24 h. Real-time fluorescence quantitative PCR （RT-qPCR） method was used to detect the expression levels of tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， interleukin-1β （IL-1β）， SLC7A11， and GPX4 mRNA in the cells in various groups； Western blotting method was used to detect the expression levels of SLC7A11 and GPX4 proteins in the cells in various groups； 2'，7'-dichlorodi-hydrofluorescein diacetate （DCFH-DA） fluorescence probe method was used to detect the levels of reactive oxygen species（ROS） in the cells in various groups.

The results of RT-qPCR method showed that compared with control group， the expression levels of TNF-α， IL-6， and IL-1β mRNA in the cells in 1 and 10 mg·L^－1 P.g-LPS groups were significantly increased（P<0.05）， while the expression levels of SLC7A11 and GPX4 mRNA were significantly decreased（P<0.05）.The results of Western blotting method showed that compared with control group， the expression levels of SLC7A11 and GPX4 proteins in the cells in 1 and 10 mg·L^－1 P.g-LPS groups were decreased（P<0.05）. The results of ROS assay showed that compared with control group， the levels of ROS in the cells in 1 and 10 mg·L^－1 P.g-LPS groups were increased（P<0.05）. Compared with 1 mg·L^－1 P.g-LPS group， the indicators mentioned above in 10 mg·L^－1 P.g-LPSgroup had significant differences.

The expressions of SLC7A11 and GPX4 in the hPDLFs under inflammation are down-regulated， suggesting that the down-regulation of SLC7A11 and GPX4 expressions may be related to the pathogenesis of periodontitis.