Further analysis of ferroptosis-associated gene expressions using RT-qPCR consistently demonstrated that periodontitis increased the expression of ferroptosis-promoting genes, including Acsl4, Socs1, Ncoa4 and Ptgs2, while exhibiting not significant impact on the expression of the ferroptosis-inhibiting gene Gpx4 (Fig. 2C). Here, SOCS1 is linked to periodontitis.