Chrm3 regulates LPS-induced inflammation in peritoneal macrophages in Lbp-/-mice via the MAPK/ERK signaling pathway
10.3969/j.issn.1671-7856.2025.04.007
- VernacularTitle:Chrm3通过MAPK/ERK途径调节LPS诱导的Lbp-/-小鼠腹腔巨噬细胞炎症
- Author:
Zhida CHEN
1
;
Bin FU
;
Sidi LI
;
Sai LIU
;
Zhongkun GUO
;
Yue ZHANG
;
Kezhou WANG
Author Information
1. 山东第一医科大学(山东省医学科学院)实验动物学院(省实验动物中心),济南 250117
- Publication Type:Journal Article
- Keywords:
Chrm3;
Lbp-/-mice;
peritoneal macrophages;
4-damp;
RNAi;
overexpression;
MAPK signaling pathway
- From:
Chinese Journal of Comparative Medicine
2025;35(4):69-78
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the role of cholinergic receptor muscarinic 3(Chrm3)in regulating lipopolysaccharide(LPS)-induced inflammation in peritoneal macrophages in lipopolysaccharide binding protein(LBP)-knockout(Lbp-/-)mice.Methods Peritoneal macrophages were isolated from wild-type and Lbp-/-mice to establish an LPS-induced inflammation model.Chrm3 expression in Lbp-/-mouse peritoneal macrophages was inhibited by 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide(4-damp)and small interfering(siRNA)and Chrm3 overexpression was achieved by lentivirus transfection.For 4-damp inhibition,cells were divided into control,LPS,and inhibitor groups,and for siRNA transfection,cells were divided into control,LPS,si-normal control group,and si-Chrm3 groups.For overexpression,cells were divided into control,LPS,negative control,and overexpression groups.Changes in Chrm3 in response to LPS stimulation were verified by Western blot.The effects of 4-damp,si-Chrm3,and lentivirus on cell inflammation and survival were confirmed by Cell Counting Kit-8,quantitative polymerase chain reaction,and Western blot assays.Results Chrm3 protein expression was significantly elevated in Lbp-/-peritoneal macrophages post-LPS stimulation(P＜0.001),whereas there was no notable change in wild-type cells.The cell survival rate was significantly increased in the 4-damp and si-Chrm3 groups(P＜0.05,P＜0.01),and cell survival was significantly reduced in the overexpression group(P＜0.01).Furthermore,4-damp and si-Chrm3 significantly reduced expression levels of the inflammatory factors tumor necrosis factor(TNF)-α,interleukin(IL)-1β,IL-6(P＜0.01,P＜0.001),and phospho-extracellular signal-regulated kinase(p-ERK)(P＜0.01,P＜0.001),which are associated with cell damage and inflammation.In contrast,TNF-α,IL-1β,IL-6(P＜0.001),and p-ERK protein(P＜0.001)were significantly elevated in the overexpression group.Conclusions LPS stimulation upregulated the expression of Chrm3 and proinflammatory cytokines in Lbp-/-peritoneal macrophages.Specific downregulation of Chrm3 by 4-damp and si-Chrm3 significantly decreased LPS-induced proinflammatory cytokines in Lbp-/-peritoneal macrophages,while upregulation of Chrm3 using overexpressing lentivirus significantly elevated the expression of related inflammatory factors.Chrm3 is implicated in the regulation of the LPS-induced inflammation response in peritoneal macrophages in Lbp-/-mice.
