Long non-coding RNA MALAT1 silencing elevates microRNA-26a-5p to ameliorate myocardial injury in sepsis by reducing regulator of calcineurin 2

Knockdown of LncRNA Lcn2-204 alleviates sepsis-induced myocardial injury by regulation of iron overload and ferroptosis

Ferroptosis is an iron-dependent programmed cell death form resulting from lipid peroxidation damage, it plays a key role in organ damage and tumor development from various causes. Sepsis leads to severe host response after infection with high mortality. The long non-coding RNAs (LncRNAs) are involved in different pathophysiological mechanisms of multiple diseases. Here, we used cecal ligation and puncture (CLP) operation to mimic sepsis induced myocardial injury (SIMI) in mouse model, and LncRNAs and mRNAs were profiled by Arraystar mouse LncRNA Array V3.0. Based on the microarray results, 552 LncRNAs and 520 mRNAs were differentially expressed in the sham and CLP groups, among them, LncRNA Lcn2-204 was the highest differentially expressed up-regulated LncRNA. Iron metabolism disorder was involved in SIMI by bioinformatics analysis, meanwhile, myocardial iron content and lipocalin-2 (Lcn2) protein expressions were increased. The CNC network comprised 137 positive interactions and 138 negative interactions. Bioinformatics analysis showed several iron-related terms were enriched and six genes (Scara5, Tfrc, Lcn2, Cp, Clic5, Ank1) were closely associated with iron metabolism. Then, we constructed knockdown LncRNA Lcn2-204 targeting myocardium and found that it ameliorated cardiac injury in mouse sepsis model through modulating iron overload and ferroptosis. In addition, we found that LncRNA Lcn2-204 was involved in the regulation of Lcn2 expression in septic myocardial injury. Based on these findings, we conclude that iron overload and ferroptosis are the key mechanisms leading to myocardial injury in sepsis, knockdown of LncRNA Lcn2-204 plays the cardioprotective effect through inhibition of iron overload, ferroptosis and Lcn2 expression. It may provide a novel therapeutic approach to ameliorate sepsis-induced myocardial injury.

Identification of New, Translatable ProtectomiRs against Myocardial Ischemia/Reperfusion Injury and Oxidative Stress: The Role of MMP/Biglycan Signaling Pathways

INTRODUCTION

Ischemic conditionings (ICon) were intensively investigated and several protective signaling pathways were identified. Previously, we have shown the role of matrix metalloproteinases (MMP) in myocardial ischemia/reperfusion injury (MIRI) and the cardioprotective role of biglycan (BGN), a small leucine-rich proteoglycan in vitro. Here, we hypothesized that cardiac MMP and BGN signaling are involved in the protective effects of ICon.

METHODS

A reverse target-microRNA prediction was performed by using the miRNAtarget™ 2.0 software to identify human microRNAs with a possible regulatory effect on MMP and BGN, such as on related genes. To validate the identified 1289 miRNAs in the predicted network, we compared them to two cardioprotective miRNA omics datasets derived from pig and rat models of MIRI in the presence of ICons.

RESULTS

Among the experimentally measured miRNAs, we found 100% sequence identity to human predicted regulatory miRNAs in the case of 37 porcine and 24 rat miRNAs. Upon further analysis, 42 miRNAs were identified as MIRI-associated miRNAs, from which 24 miRNAs were counter-regulated due to ICons.

CONCLUSIONS

Our findings highlight 24 miRNAs that potentially regulate cardioprotective therapeutic targets associated with MMPs and BGN in a highly translatable porcine model of acute myocardial infarction.

ncRS: A resource of non-coding RNAs in sepsis

Sepsis, a life-threatening condition triggered by the body's response to infection, presents a significant global healthcare challenge characterized by disarrayed host responses, widespread inflammation, organ impairment, and heightened mortality rates. This study introduces the ncRS database (http://www.ncrdb.cn), a meticulously curated repository housing 1144 experimentally validated non-coding RNAs (ncRNAs) intricately linked with sepsis. ncRS offers comprehensive RNA data, exhaustive experimental insights, and integrated annotations from diverse databases. This resource empowers researchers and clinicians to decipher ncRNAs' roles in sepsis pathogenesis, potentially identifying vital biomarkers for early diagnosis and prognosis, thus facilitating personalized treatments.

Identification of JPX-RABEP1 Pair as an Immune-Related Biomarker and Therapeutic Target in Pulmonary Arterial Hypertension by Bioinformatics and Experimental Analyses

Pulmonary arterial hypertension (PAH) is a pulmonary vascular disease characterized by pulmonary vascular remodeling and right heart enlargement the pathogenesis of PAH is complicated; no biologic-based therapy is available for the treatment of PAH, but recent studies suggest that inflammatory response and abnormal proliferation of pulmonary artery smooth muscle cells are the main pathogenic mechanism, while the role of immune-related long non-coding RNAs (lncRNAs) remains unclear. The aim of this study was to systematically analyze immune-related lncRNAs in PAH. Here, we downloaded a publicly available microarray data from PAH and control patients (GSE113439). A total of 243 up-regulated and 203 down-regulated differentially expressed genes (DEGs) were screened, and immune-related DEGs were further obtained from ImmPort. The immune-related lncRNAs were obtained by co-expression analysis of immune-related mRNAs. Then, immune-related lncRNAs-mRNAs network including 2 lncRNAs and 6 mRNAs was constructed which share regulatory miRNAs and have significant correlation. Among the lncRNA-mRNA pairs, one pair (JPX-RABEP1) was verified in the validating dataset GSE53408 and PAH mouse model. Furthermore, the immune cell infiltration analysis of the GSE113439 dataset revealed that the JPX-RABEP1 pair may participate in the occurrence and development of PAH through immune cell infiltration. Together, our findings reveal that the lncRNA-mRNA pair JPX-RABEP1 may be a novel biomarker and therapeutic target for PAH.

Long Noncoding RNA FBXL19-AS1-Mediated Ulcerative Colitis-Associated Intestinal Epithelial Barrier Defect

BACKGROUND

This study commenced to uncover the role of long non-coding RNA FBXL19 antisense RNA 1 (FBXL19-AS1) in the development of ulcerative colitis (UC) and its possible mechanism.

METHODS

FBXL19-AS1 expression in the colonic sigmoid mucosa of UC patients was detected. A colitis model was induced in mice using 5% dextran sodium sulfate. Hematoxylin-eosin staining was performed for histopathological examination. Apoptosis was detected by Tunel staining and tissue fibrosis was detected by immunohistochemistry. Also, intestinal permeability was examined. The concentrations of inflammatory factors IL-1β and IL-18 were detected by enzyme-linked immunosorbent assay. The relationship between FBXL19-AS1, miR-339-3p and RHOB was verified by RNA immunoprecipitation assay and dual luciferase reporter assay.

RESULTS

The expression of FBXL19-AS1 was increased in dextran sodium sulfate (DSS)-induced colitis mouse model. FBXL19-AS1 interference or miR-339-3p overexpression inhibited DSS-induced colonic epithelial cell apoptosis and inflammatory response, and improved intestinal epithelial barrier defects, thereby ameliorating DSS-induced colitis injury in mice. FBXL19-AS1 sponged miR-339-3p while miR-339-3p targeted RHOB. Overexpression of RHOB reversed the protective effect of inhibition of FBXL19-AS1 on DSS-induced colitis in mice.

CONCLUSION

FBXL19-AS1 reduces miR-339-3p-mediated targeting of RHOB and aggravates intestinal epithelial barrier defect in DSS-induced colitis in mice.

Elevated Serum Regulator of Calcineurin 2 is Associated With an Increased Risk of Non-Alcoholic Fatty Liver Disease

Background: The promoting effect of the regulator of calcineurin 2 (RCAN2) in hepatic steatosis has been observed in animal studies. However, the association of RCAN2 with non-alcoholic fatty liver disease (NAFLD) in humans remains unclear. This study aimed to evaluate the expression of RCAN2 in the liver of mice with hepatic steatosis and in the serum of NAFLD patients and to explore the relationship between serum RCAN2 levels and NAFLD.

Methods: The mRNA and protein expression of RCAN2 were detected by quantitative real-time PCR (qRT-PCR) and Western blot. NAFLD was diagnosed by abdominal ultrasonography. Circulating RCAN2 levels were measured by ELISA kits. The relationship between serum RCAN2 levels and NAFLD was assessed.

Results: qRT-PCR and Western blot analysis showed that compared with the corresponding controls, the mRNA and protein expression of RCAN2 were significantly increased in the liver tissues of db/db and mice on a high-fat diet. Serum RCAN2 levels were markedly elevated in NAFLD patients compared with non-NAFLD subjects. Binary logistic regression analysis showed that serum RCAN2 levels were significantly associated with NAFLD. Receiver operation characteristic (ROC) curve analysis showed that serum RCAN2 might act as a predictive biomarker for NAFLD [area under the curve (AUC) = 0.663, 95% CI = 0.623–0.702], and the serum RCAN2/(AST/ALT) ratio displayed improved predictive accuracy (AUC = 0.816, 95% CI = 0.785–0.846).

Conclusion: Elevated serum RCAN2 levels were associated with an increased risk of NAFLD. Serum RCAN2, especially the serum RCAN2/(AST/ALT) ratio, might be a candidate diagnostic marker for NAFLD.