Role of intestinal macrophages in food antigen-induced abdominal pain in mice with visceral hypersensitivity
10.3760/cma.j.cn112138-20241015-00690
- VernacularTitle:肠巨噬细胞在食物抗原诱发的内脏高敏感小鼠腹痛中的机制研究
- Author:
Li LIU
1
;
Zhipeng ZHAO
1
;
Xiaohui SHEN
1
;
Yuwei WANG
1
;
Changqing YANG
1
Author Information
1. 长治医学院附属和平医院消化内科，长治 046000
- Publication Type:Journal Article
- Keywords:
Irritable bowel syndrome;
Macrophages;
Reactive oxygen species
- From:
Chinese Journal of Internal Medicine
2025;64(8):745-752
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To examine the role of intestinal macrophages and the mechanism by which they produce reactive oxygen species (ROS) in abdominal pain induced by food antigens in mice with visceral hypersensitivity.Methods:Mouse models of visceral hypersensitivity were established by subjecting animals to acute cold restraint stress (ACRS) or acetic acid enema (AAE). Visceral sensitivity was evaluated using food antigen ovalbumin (OVA)-induced responses and rectal reflex measurements following ROS scavenging. The activity of intestinal macrophages was assessed using flow cytometry. In vitro enzyme immunoassays and in vivo imaging techniques were employed to quantify ROS levels. Furthermore, the influence of OVA on ROS levels following intestinal macrophage depletion was investigated. Cell culture experiments were conducted to investigate the effects of OVA on intestinal macrophage function and ROS production.Results:The two visceral hypersensitivity mouse models exhibited a significantly lower pain threshold compared to the control group. OVA-induced visceral hypersensitivity mice demonstrated enhanced visceral motor responses (VMRs), with an increase in abdominal ROS levels (ACRS vs. control: 62.00±7.68 vs. 19.80±2.39, P<0.001; AAE vs. control: 461.80±17.25 vs. 19.80±2.39, P<0.001). When ROS were cleared from the abdominal cavity of mice, VMRs were restored to normal levels (AAE vs. AAE+ROS: 83.50±8.72 vs. 71.66±2.67, P=0.010). In this mouse model, intestinal macrophages could be classified into CD45 Med and CD45 High subtypes based on the level of CD45 expression. In the AAE group, the expression of CD45 Med macrophages in the intestinal tract decreased (AAE vs. control: 0.121±0.026 vs. 0.194±0.021, P=0.007), whereas the expression of CD45 High macrophages increased (AAE vs. control: 0.249±0.087 vs. 0.018±0.003, P=0.027). Compared with the control group, the expression of CD11b in both types of macrophages increased significantly (CD45 Med vs. control: 39 547.00±4 422.59 vs. 4 055.67±506.05, P<0.05; CD45 High vs. control: 18 960.00±1 197.84 vs. 3 147.50±286.38, P=0.008), while the expression of F4/80 decreased (CD45 Med vs. control: 6 141.67±750.06 vs. 10 544.33±974.92, P=0.008; CD45 High vs. control: 1 291.50±119.50 vs. 4 007.50±327.39, P<0.001). These findings suggest that the activity of intestinal macrophages in visceral hypersensitivity mice is altered following OVA induction. By injecting different populations of macrophages into the peritoneal cavity of mice, it was found that compared to the AAE group, the injection of CD45 High macrophages significantly increased the VMR in mice (AAE vs. AAE CD45 High: 83.50±8.72 vs. 114.38±7.15, P<0.001), and aggravated the severity of diarrhea significantly. In vitro experiments revealed that food antigens could directly induce ROS production in macrophages. Compared with the control group, both the ACRS and AAE groups of mice exhibited significant diarrhea symptoms. In contrast, the severity of diarrhea in the Macrophages exhaust+ACRS and Macrophages exhaust+AAE groups was substantially reduced, with a significantly shortened recovery period. Additionally, compared with the AAE group, the degree of diarrhea in the AAE+ROSS group was alleviated. Conclusions:Food antigens may act on intestinal macrophages, inducing abdominal pain and diarrhea in visceral hypersensitive mice via the ROS pathway. CD45 High macrophages may play a pivotal role in this process.
