LncRNA H19 via miR-29a-3p is involved in lung inflammation and pulmonary fibrosis induced by neodymium oxide

LncRNA SNHG5/IGF2BP1/Occludin axis regulates Nd2O3 induced blood-testis barrier disruption

Neodymium oxide (Nd2O3) is a rare earth element that can lead to various type of tissue and organ damage with prolonged exposure. The long noncoding RNA small nucleolar ribonucleic acid host gene 5 (lncRNA SNHG5) plays a role in disease progressiong. However, its connection with Nd2O3 induced reproductive harm in males has not been thoroughly investigated. Our research discovered that exposure to Nd2O3 increases the expression of SNHG5 in the testes of mice, which in turn binds directly to and reduces in the protein levels of insulin like growth factor 2 mRNA-binding protein 1 (IGF2BP1) both in vivo and in vitro. This process disrupts the cytoskeleton of blood-testis barrier(BTB) by impacting the stability of the tight junction protein Occludin (Ocln) mRNA structure and the permeability of the BTB. In summary, our study elucidates the regulatory mechanism of SNHG5/IGF2BP1/Occludin axis in Nd2O3-induced BTB injury, providing valuable insights for the treatment of male infertility.

A protective role of nintedanib in peritoneal fibrosis through H19-EZH2-KLF2 axis via impeding mesothelial-to-mesenchymal transition

BACKGROUND

Peritoneal fibrosis (PF), a common complication of long-term peritoneal dialysis, accounts for peritoneal ultrafiltration failure to develop into increased mortality. Nintedanib has previously been shown to protect against multi-organ fibrosis, including PF. Unfortunately, the precise molecular mechanism underlying nintedanib in the pathogenesis of PF remains elusive.

METHODS

The mouse model of PF was generated by chlorhexidine gluconate (CG) injection with or without nintedanib administration, either with the simulation for the cell model of PF by constructing high-glucose (HG)-treated human peritoneal mesothelial cells (HPMCs). HE and Masson staining were applied to assess the histopathological changes of peritoneum and collagen deposition. FISH, RT-qPCR, western blot and immunofluorescence were employed to examine distribution or expression of targeted genes. Cell viability was detected using CCK-8 assay. Cell morphology was observed under a microscope. RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assays were applied to validate the H19-EZH2-KLF2 regulatory axis.

RESULTS

Aberrantly overexpressed H19 was observed in both the mouse and cell model of PF, of which knockdown significantly blocked HG-induced mesothelial-to-mesenchymal transition (MMT) of HPMCs. Moreover, loss of H19 further strengthened nintedanib-mediated suppressive effects against MMT process in a mouse model of PF. Mechanistically, H19 could epigenetically repressed KLF2 via recruiting EZH2. Furthermore, TGF-β/Smad pathway was inactivated by nintedanib through mediating H19/KLF2 axis.

CONCLUSION

In summary, nintedanib disrupts MMT process through regulating H19/EZH2/KLF2 axis and TGF-β/Smad pathway, which laid the experimental foundation for nintedanib in the treatment of PF.

Expression Profiles and Bioinformatic Analysis of Circular RNAs in Db/Db Mice with Cardiac Fibrosis

Introduction

Cardiac fibrosis is one of the important causes of heart failure and death in diabetic cardiomyopathy (DCM) patients. Circular RNAs (circRNAs) are covalently closed RNA molecules in eukaryotes and have high stability. Their role in myocardial fibrosis with diabetic cardiomyopathy (DCM) remain to be fully elucidated. This study aimed to understand the expression profiles of circRNAs in myocardial fibrosis with DCM, exploring the possible biomarkers and therapeutic targets for DCM.

Methods

At 21 weeks of age, db/db mice established the type 2 DCM model measured by echocardiography, and the cardiac tissue was extracted for Hematoxylin-eosin, Masson's trichrome staining, and transmission electron microscopy. Subsequently, the expression profile of circRNAs in myocardial fibrosis of db/db mice was constructed using microarray hybridization and verified by real-time quantitative polymerase chain reaction. A circRNA-microRNA-messenger RNA coexpression network was constructed, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were done.

Results

Compared with normal control mice, db/db mice had 77 upregulated circRNAs and 135 downregulated circRNAs in their chromosomes (fold change ≥1.5, P ≤ 0.05). Moreover, the enrichment analysis of circRNA host genes showed that these differentially expressed circRNAs were mainly involved in mitogen-activated protein kinase signaling pathways. CircPHF20L1, circCLASP1, and circSLC8A1 were the key circRNAs. Moreover, circCLASP1/miR-182-5p/Wnt7a, circSLC8A1/miR-29b-1-5p/Col12a1, and most especially circPHF20L1/miR-29a-3p/Col6a2 might be three novel axes in the development of myocardial fibrosis in DCM.

Conclusion

The findings will provide some novel circRNAs and molecular pathways for the prevention or clinical treatment of DCM through intervention with specific circRNAs.

Suppression of long noncoding RNA SNHG6 alleviates cigarette smoke-induced lung inflammation by modulating NF-κB signaling

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a widespread inflammatory disease with a high mortality rate. Long noncoding RNAs play important roles in pulmonary diseases and are potential targets for inflammation intervention.

METHODS

The expression of small nucleolar RNA host gene 6 (SNHG6) in mouse lung epithelial cell line MLE12 with or without cigarette smoke extract (CSE) treatment was first detected using quantitative reverse-transcription PCR. ELISA was used to evaluate the release of inflammatory cytokines (TNF-α, IL-1β, and IL-6). The binding site of miR-182-5p with SNHG6 was predicted by using miRanda, which was verified by double luciferase reporter assay.

RESULTS

Here, we revealed that SNHG6 was upregulated in CS-exposed MLE12 alveolar epithelial cells and lungs from COPD-model mice. SNHG6 silencing weakened CS-induced inflammation in MLE12 cells and mouse lungs. Mechanistic investigations revealed that SNHG6 could upregulate IκBα kinase through sponging the microRNA miR-182-5p, followed by activated NF-κB signaling. The suppressive effects of SNHG6 silencing on CS-induced inflammation were blocked by an miR-182-5p inhibitor.

CONCLUSION

Overall, our findings suggested that SNHG6 regulates CS-induced inflammation in COPD by activating NF-κB signaling, thereby offering a novel potential target for COPD treatment.

Analyzing the expression pattern of the noncoding RNAs (HOTAIR, PVT-1, XIST, H19, and miRNA-34a) in PBMC samples of patients with COVID-19, according to the disease severity in Iran during 2022-2023: A cross-sectional study

Background and aims

MicroRNAs (miRNAs) and long noncoding RNAs (lncRNAs) are well-known types of noncoding RNAs (ncRNAs), which have been known as the key regulators of gene expression. They can play critical roles in viral infection by regulating the host immune response and interacting with genes in the viral genome. In this regard, ncRNAs can be employed as biomarkers for viral diseases. The current study aimed to evaluate peripheral blood mononuclear cell (PBMC) ncRNAs (lncRNAs-homeobox C antisense intergenic RNA [HOTAIR], -H19, X-inactive-specific transcript [XIST], plasmacytoma variant translocation 1 [PVT-1], and miR-34a) as diagnostic biomarkers to differentiate severe COVID-19 cases from mild ones.

Methods

Candidate ncRNAs were selected according to previous studies and assessed by real-time polymerase chain reaction in the PBMC samples of patients with severe coronavirus disease 2019 (COVID-19) (n = 40), healthy subjects (n = 40), and mild COVID-19 cases (n = 40). Furthermore, the diagnostic value of the selected ncRNAs was assessed by analyzing the receiver-operating characteristic (ROC).

Results

The results demonstrated that the expression pattern of the selected ncRNAs was significantly different between the studied groups. The levels of HOTAIR, XIST, and miR-34a were remarkably overexpressed in the severe COVID-19 group in comparison with the mild COVID-19 group, and in return, the PVT-1 levels were lower than in the mild COVID-19 group. Interestingly, the XIST expression level in men with severe COVID-19 was higher compared to women with mild COVID-19. ROC results suggested that HOTAIR and PVT-1 could serve as useful biomarkers for screening mild COVID-19 from severe COVID-19.

Conclusions

Overall, different expression patterns of the selected ncRNAs and ROC curve results revealed that these factors can contribute to COVID-19 pathogenicity and can be considered diagnostic markers of COVID-19 severe outcomes.

A comprehensive review on the emerging role of long non-coding RNAs in the regulation of NF-κB signaling in inflammatory lung diseases

Public health globally faces significant risks from conditions like acute respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD), and various inflammatory lung disorders. The NF-κB signaling system partially controls lung inflammation, immunological responses, and remodeling. Non-coding RNAs (lncRNAs) are crucial in regulating gene expression. They are increasingly recognized for their involvement in NF-κB signaling and the development of inflammatory lung diseases. Disruption of lncRNA-NF-κB interactions is a potential cause and resolution factor for inflammatory respiratory conditions. This study explores the therapeutic potential of targeting lncRNAs and NF-κB signaling to alleviate inflammation and restore lung function. Understanding the intricate relationship between lncRNAs and NF-κB signaling could offer novel insights into disease mechanisms and identify therapeutic targets. Regulation of lncRNAs and NF-κB signaling holds promise as an effective approach for managing inflammatory lung disorders. This review aims to comprehensively analyze the interaction between lncRNAs and the NF-κB signaling pathway in the context of inflammatory lung diseases. It investigates the functional roles of lncRNAs in modulating NF-κB activity and the resulting inflammatory responses in lung cells, focusing on molecular mechanisms involving upstream regulators, inhibitory proteins, and downstream effectors.

The lncRNA H19/miR-29a-3p/SNIP1/c-myc regulatory axis is involved in pulmonary fibrosis induced by Nd2O3

Some rare earth elements are occupational and environmental toxicants and can cause organ and systemic damage; therefore, they have attracted global attention. Neodymium oxide (Nd2O3) is a rare earth element that is refined and significantly utilized in China. The long noncoding RNA (lncRNA) H19 is encoded by the H19/IGF2 imprinted gene cluster located on human chromosome 11p15.5. H19 has become a research focus due to its ectopic expression leading to the promotion of fibrosis. However, the mechanisms by which it causes pulmonary fibrosis are elusive. This investigation indicates that biologically active Nd2O3 increases H19, SNIP1, and c-myc, decreases miR-29a-3p, accelerates macrophage M2 polarization, and causes pulmonary fibrosis in mice lung tissues. In macrophage-differentiated THP-1 cells, Nd2O3 (25 μg/ml) enhanced H19, SNIP1, and c-myc, reduced miR-29a-3p, accelerated macrophages M2 polarization, and stimulated fibrogenic cytokine (TGF-β1) secretion. Furthermore, the coculturing of Nd2O3-treated macrophage-differentiated THP-1 cells. And human embryonic lung fibroblast cells activated lung fibroblast, which increases the levels of collagen I, α-SMA, p-Smad2/3, and Smad4, whereas H19 knockdown or miR-29a-3p upregulation in macrophages had opposite effects. Moreover, it was revealed that H19/miR-29a-3p/SNIP1/c-myc regulatory axis is involved in pulmonary fibrosis induced by Nd2O3. Therefore, this study provides new molecular insights into the mechanism of pulmonary fibrosis by Nd2O3.

microRNAs in parasite-induced liver fibrosis: from mechanisms to diagnostics and therapeutics

Chronic parasite infections in the liver pose a global threat to human and animal health, often occurring with liver fibrosis that leads to cirrhosis, liver failure, and even cancer. Hepatic fibrogenesis is a complex yet reversible process of tissue repair and is associated with various factors, including immune cells, microenvironment, gut microbiome, and interactions of the different liver cells. As a profibrogenic or antifibrogenic driver, microRNAs (miRNAs) are closely involved in parasite-induced hepatic fibrosis. This article updates the current understanding of the roles of miRNAs in hepatic fibrogenesis by parasite infections and discusses the strategies using miRNAs as candidates for diagnostics and therapeutics.