Neddylation Alleviates Methicillin-Resistant Staphylococcus aureus Infection by Inducing Macrophage Reactive Oxygen Species Production

Abstract

Neddylation, a posttranslational modification in which NEDD8 is covalently attached to target proteins, has emerged as an endogenous regulator of innate immunity. However, the role of neddylation in methicillin-resistant Staphylococcus aureus (MRSA) infection remains unknown. In this study, we found that neddylation was activated after MRSA infection in vivo and in vitro. Inhibition of neddylation with MLN4924 promoted injury of liver and kidneys in C57BL/6 mice with MRSA bloodstream infection and increased mortality. Blockade of neddylation, either pharmacologically (MLN4924, DI591) or through the use of Uba3 small interfering RNA, inhibited Cullin3 neddylation and promoted Nrf2 accumulation, thus reducing reactive oxygen species (ROS) induction and bacterial killing ability in mouse peritoneal macrophages. In summary, our findings suggest that activation of neddylation in macrophages plays a critical protective role against MRSA infection by increasing ROS production, partially by signaling through the NEDD8-Cullin3-Nrf2-ROS axis. Furthermore, our results may provide a new non-antibiotic treatment strategy for MRSA infection through targeting of neddylation.

Aberrant Expression of SLC7A11 Impairs the Antimicrobial Activities of Macrophages in Staphylococcus Aureus Osteomyelitis in Mice

“…Further gene set enrichment analysis (GSEA) indicated a significant inhibition of multiple biological processes, including macrophage activation, innate immune response, adaptive immune response, and Gram-positive bacterial defense response (Figure 1 F). Given that ROS generation is critical to effective antimicrobial activity of activated macrophages 30 , 31 , we investigated the dynamic ROS changes in primary murine bone marrow-derived macrophages (BMDMs) following S. aureus infection. Results showed that the level of ROS was significantly increased at 6 hours post-infection, followed by a marked decrease at 12 and 24 hours (Figure 1 G and 1 H).…”

“…It is known that the antibacterial activity of macrophages is closely related to the ROS generation 30 , 31 . To evaluate the role of SLC7A11 in regulating intracellular ROS levels in response to S. aureus infection, we used fluorescence probe DCFH-DA for labeling ROS.…”

“…Intriguingly, blocking SLC7A11 by erastin treatment or si -Slc7a11 significantly rescued the levels of intracellular ROS suppressed after 12 hours of S. aureus infection (Figure 3 G and 3 H). Recent studies have shown that intracellular ROS-induced lipid peroxidation of polyunsaturated fatty acids in the host helped eliminate various pathogens, including S. aureus 26 , 30 , 32 . Additionally, the changes in content of malondialdehyde (MDA), a stable end product of lipid peroxidation, directly reflect the degrees of lipid peroxidation 33 .…”

Extracellular vesicles derived from M2‐like macrophages alleviate acute lung injury in a miR‐709‐mediated manner

“…Murine MH‐S cells (CRL‐2019) were purchased from the American Type Culture Collection (Manassas, VA, USA), and acute monocytic leukaemia THP‐1 cells (TCHu57) were purchased from the Type Culture Collection of the Chinese Academy of Sciences (Shanghai, China). Mouse primary peritoneal macrophages (MP‐Mφ) were isolated from mice as previously described (Xiu et al., 2021 ) and the isolation service of human primary CD14 + monocytes (HP‐Mφ) from peripheral blood mononuclear cells was provided by Milestone Biotechnology (Hangzhou, China). MH‐S and THP‐1 cells, as well as MP‐Mφ and HP‐Mφ, were cultured in RPMI‐1640 (Basalmedia) supplemented with 10% FBS (Thermo Fisher Scientific) and 1% penicillin/streptomycin, respectively.…”

Association Between Neddylation and Immune Response

“…Except for affecting inflammatory responses, MLN4924 also promotes polarization towards M2 macrophages ( Asare et al, 2017 ). The neddylation pathway was found to be activated during methicillin-resistant Staphylococcus aureus (MRSA) infection, providing protection through the NEDD8-Cullin3-Nrf2-ROS axis and increased reactive oxygen species (ROS) in mouse peritoneal macrophages ( Xiu et al, 2021 ). Moreover, neddylation inhibition was proved to decrease macrophage tumor infiltration through chemotactic cytokine ligand 2 (CCL2) reduction, thus modulates the tumor microenvironment and could be a potent cancer therapy ( Zhou et al, 2019 ; Meerang et al, 2020 ).…”