Iristectorigenin C suppresses LPS-induced macrophages activation by regulating mPGES-1 expression and p38/JNK pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been used clinically to treat inflammatory diseases clinically. However, the adverse effects of NSAIDs cannot be ignored. Therefore, it is critical for us to find alternative anti-inflammatory drugs that can reduce adverse reactions to herbal medicine, such as Iris tectorum Maxim., which has therapeutic effects and can treat inflammatory diseases and liver-related diseases. AIM OF THE STUDY: This study aimed to isolate active compounds from I. tectorum and investigate their anti-inflammatory effects and action mechanisms. MATERIALS AND METHODS: Fourteen compounds were isolated from I. tectorum using silica gel column chromatography, Sephadex LH-20, ODS and high performance liquid chromatography, and their structures were identified by examining physicochemical properties, ultraviolet spectroscopy, infrared spectroscopy, mass spectrometry, and nuclear magnetic resonance spectroscopy. Classical inflammatory cell models were established using lipopolysaccharide (LPS)-stimulated RAW264.7 cells and rat primary peritoneal macrophages to examine the effect of these compounds. To examine the action mechanisms, the nitric oxide (NO) levels were measured by Griess reagent and the levels of inflammatory cytokines in the supernatant were measured by ELISA; The expressions of major proteins in prostaglandin E2 (PGE2) synthesis and the nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were examined by Western blotting, and the mRNA expression levels were measured by quantitative real-time polymerase chain reaction; and the nuclear translocation of p65 was examined by high content imaging. Molecular docking was used to predict the binding of active compound to target protein. RESULTS: Our findings revealed that Iristectorigenin C (IT24) significantly inhibited the levels of NO and PGE2 without affecting cyclooxygenase (COX)-1/COX-2 expression in LPS-induced RAW264.7 cells and rat peritoneal macrophages. Furthermore, IT24 was shown to decrease the expression of microsomal prostaglandin synthetase-1 (mPGES-1) in LPS-induced rat peritoneal macrophages. IT24 did not suppress the phosphorylation and nuclear translocation of proteins in the NF-κB pathway, but it inhibited the phosphorylation of p38/JNK in LPS-stimulated RAW264.7 cells. Additionally, molecular docking analysis indicated that IT24 may directly bind to the mPGES-1 protein. CONCLUSION: IT24 might inhibit mPGES-1 and the p38/JNK pathway to exert its anti-inflammatory effects and could be also developed as an inhibitor of mPGES-1 to prevent and treat mPGES-1-related diseases, such as inflammatory diseases, and holds promise for further research and drug development.

The complete plastome of a cultivar of Lannea coromandelica.

Lannea coromandelica (Houtt.) Merr. is a deciduous tree in the family Anacardiaceae, which grows in lowland and hill forests; 100-1800 m. SW Guangdong, S Guangxi, S Yunnan [Bhutan, India, Myanmar, Nepal, Sri Lanka; cultivated elsewhere in continental SE Asia, such as in Cambodia, Laos, Malaysia, Thailand, Vietnam, where it is probably naturalized]. The length of the complete plastome is 162,460 bp, including 130 genes consisting of 85 protein-coding genes, 37 tRNA genes and 8 rRNA genes. The assembled plastome has the typical structure and gene content of angiosperms plastome, which includes two inverted repeats (IRs) regions of 26,877 bp, a large single copy (LSC) region of 89,599 bp and a small single-copy (SSC) region of 19,107 bp. The total G/C content in the plastome of L. coromandelica is 37.7%. The complete plastome sequence of L. coromandelica will provide contributions to the conservation genetics of this species as well as to phylogenetic studies in Anacardiaceae.