Study on the mechanism of action of short-chain fatty acid in inhibiting M1 type alveolar macrophage polarization
10.3760/cma.j.issn.1671-0282.2024.04.012
- VernacularTitle:短链脂肪酸抑制M1型肺泡巨噬细胞极化的作用机制研究
- Author:
Jian CHEN
1
;
Weidong ZHOU
;
Jinlan MA
;
Libing MA
;
Xiaojun YANG
Author Information
1. 宁夏医科大学第一临床医学院,银川 750004
- Keywords:
Short-chain fatty acid;
Macrophage polarization;
AMPK/Nrf2/HO-1 signaling pathway;
Inflammation
- From:
Chinese Journal of Emergency Medicine
2024;33(4):522-528
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the effect of short-chain fatty acid (SCFA) sodium butyrate (NaB) on the polarization of lipopolysaccharide(LPS) induced M1 type alveolar macrophages and the mechanism of action.Methods:Mouse alveolar macrophages (MH-S) were randomly(random number) divided into control group (Control group), sodium butyrate group (NaB group), LPS group, LPS+NaB group (LB group), and LPS+NaB+adenylate activated protein kinase (AMPK) inhibitor (Compound C) group (LC group).The mRNA expression levels of interleukin 6 (IL-6), interleukin 1β(IL-1β), tumor necrosis factor α(TNF-α), cluster of differentiation 86 (CD86), inducible nitric oxide synthase(iNOS) in MH-S cells, and zonula occludens 1 (ZO-1), tight junction protein 4(Claudin-4), and closed protein(Occludin) in mouse lung epithelial cells (MLE-12) were detected by qRT-PCR;Protein levels of IL-6, IL-1β, and TNF-α in the supernatant of MH-S cell medium were measured by ELISA;Western blot determed the protein expression of AMPK, P-AMPK, nuclear factor E2-related factor 2 (Nrf2), and heme oxygenase 1 (HO-1) in MH-S cells;Expression of M1 type macrophage-associated markers CD86 and iNOS were determined by flow cytometry.Results:(1) qRT-PCR and ELISA results were consistent, M1 type macrophage-associated proinflammatory cytokines IL-6, IL-1β and TNF-α significantly reduced in the LB group after NaB addition compared with the LPS ground (all P <0.05); (2)The results of qRT-PCR and flow cytometry were consistent,compared with the LPS group, the LB group showed a significant decrease in M1 type macrophage-related polarization indicators CD86 and iNOS after NaB addition(all P<0.05); (3) Western blot was used to detect the expression of the AMPK/Nrf2/HO-1 signaling pathway,compared with LPS,the addition of NaB in the LB group enhanced the expression of P-AMPK/AMPK, Nrf2 (nucleus), and HO-1 (all P<0.05); compared with the LB group, the LC group decreased the expression of P-AMPK/AMPK, Nrf2 (nucleus), and HO-1 (all P<0.05);the results of flow cytometry showed that compared with the LPS group, the addition of NaB significantly decreased the expression level of iNOS + in the LB group ( P<0.05); compared with the LB group, the addition of Compound C in the LC group reversed the inhibitory effect of NaB on iNOS + ( P <0.05);(4) The qRT-PCR results of MLE-12 cells showed that compared with the LPS group, the LB group showed a significant increase in Z0-1, Claudin-4, and Occludin after the addition of NaB(all P<0.05). Conclusions:SCFA inhibits LPS-induced polarization of M1-type alveolar macrophages and ameliorates the inflammatory response by activating the AMPK/Nrf2/HO-1 signaling pathway.
