Isoalantolactone inhibits LPS‐induced inflammatory responses in macrophages

Isoalantolactone (ISO) is a main sesquiterpene lactone isolated from Inula helenium, which has been reported to have anti‐inflammatory and anti‐oxidative effects. However, the effect of ISO on LPS‐induced inflammatory responses has not been extensively studied. Herein we examine the anti‐inflammatory effects of ISO by LPS‐activated murine macrophages, J774A.1 cells. Cell viability was examined by MTT assay. The production of nitric oxide (NO) was analyzed using Griess reagent assay. The expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) was detected by Western blot. The secretion of pro‐inflammatory cytokines including tumor necrosis factor‐alpha (TNF‐α) and interleukin‐6 (IL‐6) was determined using ELISA. Our experimental results showed that dose of ISO under 10 μM had no toxicity in J774A.1 cells. To avoid the toxic effect of ISO, the dose of ISO used in this study was less than or equal to 10 μM. Our experimental results indicated that ISO inhibits the production of NO, decreases the expression of iNOS and COX‐2, and attenuated the secretion of TNF‐α and IL‐6 in J774A.1 cells. Collectively, our experimental results demonstrated that ISO suppresses LPS‐induced inflammatory responses in macrophages. These results suggest that ISO might has potential against LPS‐induced overactive inflammation. Support or Funding Information This study was supported by the Ministry of Science and Technology, Taiwan, R.O.C. (Grant No. MOST 107‐2320‐B‐037‐019). This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .