NLRP3 인플라마좀 유전자 발현 억제가 시르투인 경로와 염증조절인자에 미치는 영향

Effects of NLRP3 inflammasome knockdown on sirtuin pathway and inflammatory markers in AML12 mouse hepatocytes

Nucleotide binding and oligomerization domain (NOD)-like receptor family, pryin domain containing 3 (NLRP3) inflammasome is the protein complex regulating interleukin-1 (IL-1) secretion and consists of NLRP3, apoptosis-associated speck-like protein containing a caspase activation recruitment domain (ASC), and caspase 1. Initial studies on inflammasomes were primarily focused on innate immunity; however, recent reports have demonstrated that NLRP3 inflammasome may be responsible for the development and progression of inflammation-related diseases including obesity and type 2 diabetes. The aim of this study was to investigate the effects of NLRP3 knockdown on the sirtuin pathway and inflammation in AML12 mouse hepatocytes. RNA interference (RNAi)-mediated gene silencing was performed for NLRP3 knockdown. After 48 h of transfection with small interfering RNA(siRNA) targeting NLRP3, components of sirtuin pathway and markers of inflammation were analysed in cell lysates. NLRP3 knockdown for 48 h had no effect on hepatocyte morphology and cell number. The transfection efficiency and knockdown rate of NLRP3 were confirmed. NLRP3 knockdown in hepatocytes had no effect on sirtuin pathway-related factors: sirtuin 1 (Sirt1), Sirt6, adiponectin, and peroxisome proliferator-activated receptor gamma coactivator-1-alpha (PGC-1 alpha). However, the NLRP3 knockdown in hepatocytes down-regulated those of pro-inflammatory markers such as IL-6 and tumor necrosis factor-alpha (TNF-alpha). Our results demonstrate that RNAi-mediated inhibition of NLRP3 inflammasome alters inflammation in hepatocytes without affecting sirtuin pathway. We propose NLRP3 as a potential therapeutic target for inflammationrelated diseases.