In vitro and in vivo biological evaluation of Lappaconitine derivatives as potential anti-inflammatory agents

Natural products and their derivatives are a precious treasure in the pursuit of potent anti-inflammatory drugs. In this work, we measured the toxicity of 78 LA derivatives at 20 mu M using MTT, then we evaluated the NO release of compounds without obvious toxicity in LPS-induced RAW.264.7 by Griess reagent, we identified three compounds, namely compounds 6, 19, 70, which exhibited promising anti-inflammatory potential. These compounds exhibited IC50 values of 10.34 +/- 2.05 mu M, 18.18 +/- 4.80 mu M and 15.66 +/- 0.88 mu M. In addition, through ELISA kits, compounds 6, 19, 70 significantly reduce the production of inflammatory factors (TNF-alpha, IL-6, IL-1 beta). Real-time PCR and western blot analysis showed that compounds 6, 19, 70 inhibited the mRNA and protein expression of iNOS and COX-2. Notably, compound 6 exhibited the most potent inhibitory activity. In vitro, it inhibits LPS-induced phosphorylation of NF-kappa B p65, I kappa B alpha, ERK1/2, JNK, and p38 MAPKs in RAW264.7 cells. In vivo, compound 6 potently inhibits the secretion of inflammatory mediators and neutrophil activation in ALI mice. Our findings suggest that compound 6 may be a potential anti-inflammatory drug.