Paeonol attenuates inflammation by targeting HMGB1 through upregulating miR-339-5p.

ABSTRACT: Sepsis is a life-threatening disease caused by infection. Inflammation is a key pathogenic process in sepsis. Paeonol, an active ingredient in moutan cortex (a Chinese herb), has many pharmacological activities, such as anti-inflammatory and antitumour actions. Previous studies have indicated that paeonol inhibits the expression of HMGB1 and the transcriptional activity of NF-?B. However, its underlying mechanism is still unknown. In this study, microarray assay and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) results confirmed that paeonol could significantly up-regulate the expression of miR-339-5p in RAW264.7 cells stimulated by LPS. Dual-luciferase assays indicated that miR-339-5p interacted with the 3' untranslated region (3'-UTR) of HMGB1. Western blot, immunofluorescence and enzyme-linked immunosorbent assay (ELISA) analyses indicated that miR-339-5p mimic and siHMGB1 both negatively regulated the expression and secretion of inflammatory cytokines (e.g., HMGB1, IL-1? and TNF-?) in LPS-induced RAW264.7 cells. Studies have confirmed that IKK-? is targeted by miR-339-5p, and we further found that paeonol could inhibit IKK-? expression. Positive mutual feedback between HMGB1 and IKK-? was observed when we silenced HMGB1 or IKK-?. These results indicated that paeonol could attenuate the inflammation mediated by HMGB1 and IKK-? by upregulating miR-339-5p expression. In addition, we constructed CLP model mice by cecal ligation and puncture. Paeonol was used to intervene to investigate its anti-inflammatory effect in vivo. The results showed that paeonol could improve the survival rate of sepsis mice and protect the kidney of sepsis mice.

SUBMITTER: Mei L 

PROVIDER: S-EPMC6920373 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature