LPS inhibits TRIM65 expression in macrophages and C57BL/6J mouse by activating the ERK1/2 signaling pathway

Xufang Zeng; Xinxin Deng; Yuqi Ni; Hongfeng Bi; Meiling Jiang; Dan Wang; Pengzhi Dong; Yunfei Xiao; Meixiu Jiang

doi:10.3892/etm.2023.11887

LPS inhibits TRIM65 expression in macrophages and C57BL/6J mouse by activating the ERK1/2 signaling pathway

Exp Ther Med. 2023 Mar 14;25(4):188. doi: 10.3892/etm.2023.11887. eCollection 2023 Apr.

Authors

Xufang Zeng¹, Xinxin Deng^{2

3}, Yuqi Ni⁴, Hongfeng Bi⁵, Meiling Jiang⁶, Dan Wang², Pengzhi Dong⁷, Yunfei Xiao², Meixiu Jiang^{1

2}

Affiliations

¹ College of Life Sciences, Nanchang University, Nanchang, Jiangxi 330031, P.R. China.
² Institute of Translational Medicine, National Engineering Research Center for Bioengineering Drugs and The Technologies, Nanchang University, Nanchang, Jiangxi 330031, P.R. China.
³ School of Pharmacy, Nanchang University, Nanchang, Jiangxi 330031, P.R. China.
⁴ Central Laboratory, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, Zhejiang 321000, P.R. China.
⁵ Department of Medical Equipment, Dongying Shengli Oilfield Central Hospital, Dongying, Shandong 257034, P.R. China.
⁶ Department of Obstetrics, Dongying Shengli Oilfield Central Hospital, Dongying, Shandong 257034, P.R. China.
⁷ College of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin 301617, P.R. China.

Abstract

Activated macrophages serve a key role in various inflammatory diseases, such as atherosclerosis and septic shock. Tripartite motif-containing protein 65 (TRIM65) has been previously reported to participate in tumor progression and lung inflammation. However, the molecular mechanisms that controls its expression under inflammatory conditions and its consequences in activated macrophages remain poorly understood. The present study first collected the tissues of C57BL/6J mice, smooth muscle cells, macrophages and endothelial cells to determine the expression and distribution of TRIM65 by reverse transcription-quantitative (RT-q) PCR and western blotting. Mouse and human macrophages were treated with LPS and C57BL/6J mice were intraperitoneally injected with LPS followed by isolation of spleen, lung, aorta and bone marrow. Following treatment, TRIM65 mRNA and protein level was examined by RT-qPCR and western blotting. The results showed that TRIM65 was highly expressed in organs of the immune system, such as the spleen, lymph node and thymus, but lowly expressed in heart, liver, brain and kidneys. TRIM65 was also highly expressed in macrophages and endothelial cells. TRIM65 mRNA and protein expression levels were found to be decreased in LPS-treated macrophages in vitro and in tissues isolated from C57BL/6J mice intraperitoneally injected with LPS in vivo. In addition, to identify the signaling pathways by which LPS regulates TRIM65 expression, inhibitors of MAPK and Akt signaling pathways were used to treat macrophages followed by examination the expression of TRIM65 by western blotting. The results demonstrated that LPS-inhibited TRIM65 expression was blocked by treatment with the ERK1/2 inhibitor U0126. Moreover, the RT-qPCR results showed that TRIM65 knockout potentiated LPS-induced expression of inflammatory cytokines in macrophages. Taken together, data from the present study suggest that LPS decreased TRIM65 expression in macrophages and C57BL/6J mouse by activating the ERK1/2 signaling pathway, whilst TRIM65 knockout promoted macrophage activation. This information may facilitate the development of potential therapeutic strategies for the prevention and treatment of inflammatory diseases, such as atherosclerosis.

Keywords: ERK1/2 signaling; expression; lipopolysaccharide; macrophage; tripartite motif-containing protein 65.

Grants and funding

Funding: The present study was supported by National Natural Science Foundation of China grants (grant nos. 82160094, 82200509 and 81901546) and Natural Science Foundation of Jiangxi Province, China (grant nos. 20202BAB206087, 20212BCJ23043 and 20212BAB206087).