Silencing XIST mitigated lipopolysaccharide (LPS)-induced inflammatory injury in human lung fibroblast WI-38 cells through modulating miR-30b-5p/CCL16 axis and TLR4/NF-κB signaling pathway

Illuminating the pathogenic role of SARS-CoV-2: Insights into competing endogenous RNAs (ceRNAs) regulatory networks

The appearance of SARS-CoV-2 in 2019 triggered a significant economic and health crisis worldwide, with heterogeneous molecular mechanisms that contribute to its development are not yet fully understood. Although substantial progress has been made in elucidating the mechanisms behind SARS-CoV-2 infection and therapy, it continues to rank among the top three global causes of mortality due to infectious illnesses. Non-coding RNAs (ncRNAs), being integral components across nearly all biological processes, demonstrate effective importance in viral pathogenesis. Regarding viral infections, ncRNAs have demonstrated their ability to modulate host reactions, viral replication, and host-pathogen interactions. However, the complex interactions of different types of ncRNAs in the progression of COVID-19 remains understudied. In recent years, a novel mechanism of post-transcriptional gene regulation known as "competing endogenous RNA (ceRNA)" has been proposed. Long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and viral ncRNAs function as ceRNAs, influencing the expression of associated genes by sequestering shared microRNAs. Recent research on SARS-CoV-2 has revealed that disruptions in specific ceRNA regulatory networks (ceRNETs) contribute to the abnormal expression of key infection-related genes and the establishment of distinctive infection characteristics. These findings present new opportunities to delve deeper into the underlying mechanisms of SARS-CoV-2 pathogenesis, offering potential biomarkers and therapeutic targets. This progress paves the way for a more comprehensive understanding of ceRNETs, shedding light on the intricate mechanisms involved. Further exploration of these mechanisms holds promise for enhancing our ability to prevent viral infections and develop effective antiviral treatments.

Monocyte-derived exosomal XIST exacerbates acute lung injury by regulating the miR-448-5p/HMGB2 axis

Monocyte-derived exosomes (Exos) have been implicated in inflammation-related autoimmune/inflammatory diseases via transferring bioactive cargoes to recipient cells. The purpose of this study was to investigate the possible effect of monocyte-derived Exos on the initiation and the development of acute lung injury (ALI) by delivering long non-coding RNA XIST. Key factors and regulatory mechanisms in ALI were predicted by bioinformatics methods. BALB/c mice were treated with lipopolysaccharide (LPS) to establish an ALI in vivo model and then injected with Exos isolated from monocytes transduced with sh-XIST to evaluate the effect of monocyte-derived exosomal XIST on ALI. HBE1 cells were co-cultured with Exos isolated from monocytes transduced with sh-XIST for further exploration of its effect. Luciferase reporter, RIP and RNA pull-down assays were performed to verify the interaction between miR-448-5p and XIST, miR-448-5p and HMGB2. miR-448-5p was significantly poorly expressed while XIST and HMGB2 were highly expressed in the LPS-induced mouse model of ALI. Monocyte-derived Exos transferred XIST into HBE1 cells where XIST competitively inhibited miR-448-5p and reduced the binding of miR-448-5p to HMGB2, thus upregulating the expression of HMGB2. Furthermore, in vivo data revealed that XIST delivered by monocyte-derived Exos downregulated miR-448-5p expression and up-regulated HMGB2 expression, ultimately contributing to ALI in mice. Overall, our results indicate that XIST delivered by monocyte-derived Exos aggravates ALI via regulating the miR-448-5p/HMGB2 signaling axis.

Pan-cancer analysis of LncRNA XIST and its potential mechanisms in human cancers

Background

Methods

Results

Conclusion

Prolactin regulates H3K9ac and H3K9me2 epigenetic marks and miRNAs expression in bovine mammary epithelial cells challenged with Staphylococcus aureus

Epigenetic mechanisms are essential in the regulation of immune response during infections. Changes in the levels of reproductive hormones, such as prolactin, compromise the mammary gland’s innate immune response (IIR); however, its effect on epigenetic marks is poorly known. This work explored the epigenetic regulation induced by bovine prolactin (bPRL) on bovine mammary epithelial cells (bMECs) challenged with Staphylococcus aureus. In this work, bMECs were treated as follows: (1) control cells without any treatment, (2) bMECs treated with bPRL (5 ng/ml) at different times (12 or 24 h), (3) bMECs challenged with S. aureus for 2 h, and (4) bMECs treated with bPRL at different times (12 or 24 h), and then challenged with S. aureus 2 h. By western blot analyses of histones, we determined that the H3K9ac mark decreased (20%) in bMECs treated with bPRL (12 h) and challenged with S. aureus, while the H3K9me2 mark was increased (50%) in the same conditions. Also, this result coincided with an increase (2.3-fold) in HDAC activity analyzed using the cellular histone deacetylase fluorescent kit FLUOR DE LYS^®. ChIP-qPCRs were performed to determine if the epigenetic marks detected in the histones correlate with enriched marks in the promoter regions of inflammatory genes associated with the S. aureus challenge. The H3K9ac mark was enriched in the promoter region of IL-1β, IL-10, and BNBD10 genes (1.5, 2.5, 7.5-fold, respectively) in bMECs treated with bPRL, but in bMECs challenged with S. aureus it was reduced. Besides, the H3K9me2 mark was enriched in the promoter region of IL-1β and IL-10 genes (3.5 and 2.5-fold, respectively) in bMECs challenged with S. aureus but was inhibited by bPRL. Additionally, the expression of several miRNAs was analyzed by qPCR. Let-7a-5p, miR-21a, miR-30b, miR-155, and miR-7863 miRNAs were up-regulated (2, 1.5, 10, 1.5, 3.9-fold, respectively) in bMECs challenged with S. aureus; however, bPRL induced a down-regulation in the expression of these miRNAs. In conclusion, bPRL induces epigenetic regulation on specific IIR elements, allowing S. aureus to persist and evade the host immune response.

To Explore the Molecular Mechanism of Acupuncture Alleviating Inflammation and Treating Obesity Based on Text Mining

Objective

To explore the related mechanism of acupuncture affecting obesity by regulating inflammation using bioinformatics methods.

Methods

The genes related to obesity, inflammation, and acupuncture and inflammation were mined using GenCLiP 3, and the intersecting genes were extracted using Venn diagram. The DAVID database was employed for pathway enrichment analysis and functional annotation of coexpressed genes. Then, the protein-protein interaction (PPI) network was constructed with the STRING database and visualized by the Cytoscape software and screened out important hub genes. Finally, the Boxplot and Survival Analysis of the hub genes in various cancers were performed by GEPIA.

Results

755 genes related to obesity and inflammation and 38 genes related to acupuncture and inflammation were identified, and 24 coexpressed genes related to obesity, inflammation, and acupuncture were extracted from the Venn diagram. Eight hub genes including interleukin-6 (IL-6), interleukin-10 (IL-10), Toll-like receptor 4 (TLR4), signal transduction and transcriptional activation factor 3 (STAT3), C-X-C motif chemokine 10 (CXCL10), interleukin-17A (IL-17A), prostaglandin peroxide synthesis-2 (PTGS2), signal transistors, and transcriptional activation factor 6 (STAT6) were identified by gene ontology (GO), Kyoto Encyclopedia of Genes (KEGG), and PPI network analysis. Among them, IL-6 is suggested to play an essential role in the treatment of obesity and inflammation by acupuncture, and IL-6 was significant in both Boxplot and Survival Analysis of pancreatic cancer (PAAD). Therefore, in this study, the core gene, IL-6 was used as the breakthrough point to explore the possible mechanism of acupuncture in treating obesity and pancreatic cancer by regulating IL-6.

Conclusion

(1) Acupuncture can regulate the expression of IL-6 through the TLR4/nuclear factor-κB (NF-κB) pathway, thereby alleviating inflammation, which can be used as a potential strategy for the treatment of obesity. (2) IL-6/STAT3 is closely related to the occurrence, development, and metastasis of pancreatic cancer. Acupuncture affecting pancreatic cancer through TLR4/NF-κB/IL-6/STAT3 pathway may be a potential method for the treatment of pancreatic cancer.

Functional Roles of Chemokine Receptor CCR2 and Its Ligands in Liver Disease

Chemokines are a family of cytokines that orchestrate the migration and positioning of immune cells within tissues and are critical for the function of the immune system. CCR2 participates in liver pathology, including acute liver injury, chronic hepatitis, fibrosis/cirrhosis, and tumor progression, by mediating the recruitment of immune cells to inflammation and tumor sites. Although a variety of chemokines have been well studied in various diseases, there is no comprehensive review presenting the roles of all known chemokine ligands of CCR2 (CCL2, CCL7, CCL8, CCL12, CCL13, CCL16, and PSMP) in liver disease, and this review aims to fill this gap. The introduction of each chemokine includes its discovery, its corresponding chemotactic receptors, physiological functions and roles in inflammation and tumors, and its impact on different immune cell subgroups.

Long non-coding RNA Xist contribution in systemic lupus erythematosus and rheumatoid arthritis

Growing evidence points towards the role of the long non-coding (lnc)-RNA Xist expressed in female cells as a predominant key actor for the sex bias observed in systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Indeed, in female cells, lnc-Xist controls transcription directly by spreading across the inactivated X chromosome (Xi) and indirectly by sequestring miRNAs as a sponge. The inactivation process at Xi is altered in lymphocytes from SLE women and associated with important variations in ribonucleoproteins (RNP) associated with lnc-Xist. In fibroblast-like synoviocytes (FLS) and osteoclasts from RA women, proinflammatory and proliferative pathways are upregulated due to the sequestration effect exerted by lnc-Xist overexpression on miRNAs. The key role played by lnc-Xist in SLE and RA is further supported by it's knock down that recapitulates the SLE B cell extrafollicular profile and controls RA associated FLS proinflammatory cytokine production and proliferation.

The lncRNAs at X Chromosome Inactivation Center: Not Just a Matter of Sex Dosage Compensation

Non-coding RNAs (ncRNAs) constitute the majority of the transcriptome, as the result of pervasive transcription of the mammalian genome. Different RNA species, such as lncRNAs, miRNAs, circRNA, mRNAs, engage in regulatory networks based on their reciprocal interactions, often in a competitive manner, in a way denominated “competing endogenous RNA (ceRNA) networks” (“ceRNET”): miRNAs and other ncRNAs modulate each other, since miRNAs can regulate the expression of lncRNAs, which in turn regulate miRNAs, titrating their availability and thus competing with the binding to other RNA targets. The unbalancing of any network component can derail the entire regulatory circuit acting as a driving force for human diseases, thus assigning “new” functions to “old” molecules. This is the case of XIST, the lncRNA characterized in the early 1990s and well known as the essential molecule for X chromosome inactivation in mammalian females, thus preventing an imbalance of X-linked gene expression between females and males. Currently, literature concerning XIST biology is becoming dominated by miRNA associations and they are also gaining prominence for other lncRNAs produced by the X-inactivation center. This review discusses the available literature to explore possible novel functions related to ceRNA activity of lncRNAs produced by the X-inactivation center, beyond their role in dosage compensation, with prospective implications for emerging gender-biased functions and pathological mechanisms.

Shikonin ameliorates injury and inflammatory response of LPS-stimulated WI-38 cells via modulating the miR-489-3p/MAP2K1 axis

Pneumonia is an inflammatory disease induced by infection with different pathogens. Currently, multiple preclinical studies have revealed that shikonin, a natural naphthoquinone, can mitigate lipopolysaccharide (LPS)-induced inflammation, but its underlying mechanism in pneumonia remains unknown. This research was designed to explore the function and regulatory mechanism of shikonin in LPS-induced cell injury and inflammation in WI-38 cells. In-vitro model of pneumonia was constructed by treating WI-38 cells with LPS. Expression of miR-489-3p and MAP2K1 was tested by RT-qPCR and (or) Western blot analysis. Cell viability was examined by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay. The productions of pro-inflammatory cytokines were determined by enzyme-linked immunosorbent assays. Cell apoptosis was detected by Western blot and flow cytometry analysis. In the current study, LPS induced WI-38 cell damage by inhibiting cell viability and promoting cell apoptosis and inflammation. Shikonin ameliorated LPS-induced cell injury and elevated miR-489-3p expression. LPS-induced inflammatory injury was further mitigated by upregulation of miR-489-3p. In addition, MAP2K1, the target of miR-489-3p, was upregulated by LPS. Furthermore, upregulation of MAP2K1 reversed the influence of shikonin and miR-489-3p mimics on LPS-induced cell injury and inflammation. This study revealed that shikonin protected WI-38 cells against LPS-induced cell injury and inflammatory response by regulating the miR-489-3p/MAP2K1 axis, thus affecting the progression of pneumonia.