Two components, myrtenal and β-caryophyllene oxide, screened from PEL, showed a similar inhibitory effect on the release of IL-1β and TNF-α and the expression of NLRP3 and caspase-1 in RA-FLS, indicating they might be the major active ingredients of LF in the treatment of RA. This evidence concerns the gene CASP1 and rheumatoid arthritis.