Brucella-Induced Downregulation of lncRNA Gm28309 Triggers Macrophages Inflammatory Response Through the miR-3068-5p/NF-κB Pathway

Abstract

ObjectivesThe underlying mechanism of the inflammatory response against Brucellosis caused by Brucella remains poorly understood. This study aimed to determine the role of long non-coding RNAs (lncRNAs) in regulating of inflammatory and anti-Brucella responses.Materials and methodsMicroarray analysis was performed to detect differentially expressed lncRNAs in THP-1 cells infected with an S2308 Brucella strain. The candidate lncRNAs were screened using bioinformatic analysis and siRNAs; bioinformatic prediction and luciferase reporter assay were also conducted, while inflammatory responses was assessed using RT‐qPCR, western blot, immunofluorescence, ELISA, HE, and immunohistochemistry.ResultsThe lncRNA Gm28309 was identified to be involved in regulating inflammation induced by Brucella. Gm28309, localized in the cytoplasm, was down-expressed in RAW264.7 cells infected with S2308. Overexpression of Gm28309 or inhibition of miR-3068-5p repressed p65 phosphorylation and reduced NLRP3 inflammasome and IL-1β and IL-18 secretion. Mechanistically, Gm28309 acted as a ceRNA of miR-3068-5p to activate NF-κB pathway by targeting κB-Ras2, an inhibitor of NF-κB signaling. Moreover, the number of intracellular Brucella was higher when Gm28309 was overexpressed or when miR-3068-5p or p65 was inhibited. However, these effects were reversed by the miR-3068-5p mimic.ConclusionsOur study demonstrates, for the first time, that LncRNAs are involved in regulating immune responses during Brucella infection, and Gm28309, an lncRNA, plays a crucial role in activating NF-κB/NLRP3 inflammasome signaling pathway.

Circulating Long Noncoding RNAs Positively Correlate with the Increased Risk, Elevated Severity and Unfavorable Prognosis in the Sepsis Patients

“…To verify the role of lncRNA PKN2-AS1 and AC068888.1 in the assessment of disease severity and in ammation, our clinical study found that those two lncRNAs were signi cantly correlated with SOFA, APACHE II scores and Lac level, but weakly correlated with PCT and CRP levels. The possible explanation is that, like other lncRNAs (such as MALAT1 and NEAT1), these two lncRNAs may promote the production of in ammatory factors through the NF-κB or TLRs pathway [42,43], aggravating the in ammation and organ dysfunction. In the diagnosis of sepsis, lncRNA PKN2-AS1 (AUC = 0.704) and AC068888.1 (AUC = 0.812) clearly distinguished patients with septic shock from those without septic shock.…”

Differential Expression Profiles and Functional Prediction of circRNAs in Necrotizing Enterocolitis

“…miR-139-5p has been implicated in maintaining intestinal homeostasis and protection against colitis in vivo [ 30 ]. Inhibition of miR-3068-5p represses p65 phosphorylation and reduces NLRP3 inflammasome and IL-1 β and IL-18 secretion [ 10 ]. These findings indicate that dysregulated circRNAs may interact with these miRNAs, thus promoting NEC development.…”

“…Recent studies report that circRNAs are expressed in most human cells and serve a critical role in regulating gene expression at the posttranscriptional level [ 6 ]. circRNAs have been linked to certain diseases, such as diabetic colonic dysmotility [ 7 ], inflammatory bowel disease [ 8 ], sepsis [ 9 ], innate colitis [ 10 ], and colorectal cancer [ 11 ]. For instance, circHIPK3 was proved to be a major regulator of intestinal epithelial repair following acute injury [ 12 ].…”

The Long Noncoding RNA Gm9866/Nuclear Factor-κB Axis Promotes Macrophage Polarization

“…Then, the plasmid was directly mixed with transfection regent (1 : 1) and mixed by using a pipette (10–15 times). Following incubation at room temperature for 15 min, the mixture was added to the cell culture plates, mixed gently, and incubated in a CO 2 incubator for 24 h [ 17 ].…”