LIN28B-AS1-IGF2BP1 association is required for LPS-induced NFκB activation and pro-inflammatory responses in human macrophages and monocytes

C1632 protects against LPS-induced acute lung injury by regulating AXL-mediated MAPK/NF-κB signaling pathway

Acute lung injury (ALI), a leading pulmonary inflammatory disorder, is associated with high morbidity and mortality rates. AXL, a member of the TAM family, plays a significant role in the innate immune and inflammatory responses. This study aimed to evaluate the therapeutic potential of C1632 and its mechanisms in the treatment of LPS-induced ALI/ARDS. The results demonstrated that C1632 pretreatment inhibited the transcription, expression, and secretion of LPS-induced inflammatory factors (IL-6, TNF-α) and vascular adhesion molecules (VCAM-1, ICAM-1). Furthermore, it reduced inflammatory cell infiltration in the lungs, thereby alleviating LPS-induced histopathological changes and lung injury in mice. Mechanistically, C1632 suppressed AXL transcription and expression, which inhibited the activation of the MAPK/NF-κB signaling pathway triggered by LPS stimulation. Both in vitro and in vivo studies confirmed that C1632 administration did not exhibit significant cytotoxicity. Additionally, it did not cause functional or structural damage to the liver and kidneys in mice, nor did it induce other acute toxic effects. In summary, these findings suggest that AXL is a novel target for MAPK/NF-κB signaling pathway mediated anti-inflammatory treatment and C1632 is a promising therapeutic agent for ALI/ARDS treatment.

Administration of hypoxic pretreated adipose-derived mesenchymal stem cell exosomes promotes spinal cord repair after injury via delivery of circ-Astn1 and activation of autophagy

BACKGROUND

The aim of this study was to investigate the role and mechanism of exosomes isolated from adipose-derived mesenchymal stem cells (ADSCs) on spinal cord repair.

METHODS

High-throughput sequencing was used to investigate abnormal expression of circular RNA (circRNA) in ADSC exosomes pretreated under hypoxic conditions (HExos) and ADSCs exosomes under normal conditions (Exos). The abnormal expression of mRNA in spinal cord tissues was also analyzed using high-throughput sequencing. Bioinformatics and luciferase reporter analyses were used to clarify the relationship among circRNA, micro RNA (miRNA), and mRNA. BV2 cells were used to analyze apoptosis levels and inflammatory cytokine expression under oxygen-glucose deprivation (OGD) conditions by using immunofluorescence and enzyme-linked immunosorbent assay (ELISAs). An SCI mouse model was also constructed and the therapeutic effect of Exos was detected using immunohistochemistry and immunofluorescence.

RESULTS

High-throughput sequencing results showed that circ-Astn1 played a role in HExo-mediated spinal cord repair after SCI. Downregulation of circ-Astn1 decreased the therapeutic effect of HExos. We also found that Atg7 played a role in HExo-mediated spinal cord repair after SCI. Luciferase reporter analysis confirmed that both miR-138-5p and Atg7 were downstream targets of circ-Astn1. Downregulation of Atg7 or overexpression of miR-138-5p reversed the protective effect of circ-Astn1 on BV2 cells after exposure to OGD conditions. In contrast, upregulation of circ-Astn1 increased the therapeutic effects of Exo-mediated spinal cord repair after SCI via autophagy activation.

CONCLUSIONS

Taken together, the results indicate that ADSC-Exos containing circ-Astn1 promoted spinal cord repair after SCI by targeting the miR-138-5p/Atg7 pathway, which mediated autophagy.

Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) in hematological diseases

The oncofetal mRNA-binding protein IGF2BP1 belongs to a conserved family of RNA-binding proteins. It primarily promotes RNA stability, regulates translation and RNA localization, and mediates gene expression through its downstream effectors. Numerous studies have demonstrated that IGF2BP1 plays crucial roles in embryogenesis and carcinogenesis. IGF2BP1-modulated cell proliferation, invasion, and chemo-resistance in solid tumors have attracted researchers' attention. Additionally, several studies have highlighted the importance of IGF2BP1 in hematologic malignancies and hematological genetic diseases, positioning it as a promising therapeutic target for hematological disorders. However, there is a lack of systematic summaries regarding the IGF2BP1 gene within the hematological field. In this review, we provide a comprehensive overview of the discovery and molecular structure of IGF2BP1, along with recent studies on its role in regulating embryogenesis. We also focus on the mechanisms by which IGF2BP1 regulates hematological malignancies through its interactions with its targeted mRNAs. Furthermore, we systematically elucidate the function and mechanism of IGF2BP1 in promoting fetal hemoglobin expression in adult hematopoietic stem/progenitor cells. Finally, we discuss the limitations and challenges of IGF2BP1 as a therapeutic target, offering insights into its prospects.

XIST and MUC1-C form an auto-regulatory pathway in driving cancer progression

The long non-coding RNA X-inactive specific transcript (lncRNA XIST) and MUC1 gene are dysregulated in chronic inflammation and cancer; however, there is no known interaction of their functions. The present studies demonstrate that MUC1-C regulates XIST lncRNA levels by suppressing the RBM15/B, WTAP and METTL3/14 components of the m6A methylation complex that associate with XIST A repeats. MUC1-C also suppresses the YTHDF2-CNOT1 deadenylase complex that recognizes m6A sites and contributes to XIST decay with increases in XIST stability and expression. In support of an auto-regulatory pathway, we show that XIST regulates MUC1-C expression by promoting NF-κB-mediated activation of the MUC1 gene. Of significance, MUC1-C and XIST regulate common genes associated with inflammation and stemness, including (i) miR-21 which is upregulated across pan-cancers, and (ii) TDP-43 which associates with the XIST E repeats. Our results further demonstrate that the MUC1-C/XIST pathway (i) is regulated by TDP-43, (ii) drives stemness-associated genes, and (iii) is necessary for self-renewal capacity. These findings indicate that the MUC1-C/XIST auto-regulatory axis is of importance in cancer progression.

circ-Iqsec1 induces bone marrow-derived mesenchymal stem cell (BMSC) osteogenic differentiation through the miR-187-3p/Satb2 signaling pathway

BACKGROUND

Bone marrow-derived mesenchymal stem cells (BMSCs) are general progenitor cells of osteoblasts and adipocytes and they are characterized as a fundamental mediator for bone formation. The current research studied the molecular mechanisms underlying circRNA-regulated BMSC osteogenic differentiation.

METHODS

Next-generation sequencing (NGS) was employed to study abnormal circRNA and mRNA expression in BMSCs before and after osteogenic differentiation induction. Bioinformatics analysis and luciferase reporting analysis were employed to confirm correlations among miRNA, circRNA, and mRNA. RT-qPCR, ALP staining, and alizarin red staining illustrated the osteogenic differentiation ability of BMSCs.

RESULTS

Data showed that circ-Iqsec1 expression increased during BMSC osteogenic differentiation. circ-Iqsec1 downregulation reduced BMSC osteogenic differentiation ability. The present investigation discovered that Satb2 played a role during BMSC osteogenic differentiation. Satb2 downregulation decreased BMSC osteogenic differentiation ability. Bioinformatics and luciferase data showed that miR-187-3p linked circ-Iqsec1 and Satb2. miR-187-3p downregulation or Satb2 overexpression restored the osteogenic differentiation capability of BMSCs post silencing circ-Iqsec1 in in vivo and in vitro experiments. Satb2 upregulation restored osteogenic differentiation capability of BMSCs post miR-187-3p overexpression.

CONCLUSION

Taken together, our study found that circ-Iqsec1 induced BMSC osteogenic differentiation through the miR-187-3p/Satb2 signaling pathway.

Association between miR-126, miR-21, inflammatory factors and T lymphocyte apoptosis in septic rats

MicroRNAs (miRs) serve an important role in regulating expression levels of inflammatory factors but the underlying mechanism is still unclear. The present study aimed to observe miR-126 and miR-21 expression and apoptosis in T lymphocytes and to analyze their association with cytokine release in septic rats. The septic model rats were given intraperitoneal lipopolysaccharide (LPS) and divided into 0, 12, 24, 48 and 72 h groups. Peripheral blood was collected from each group to isolate T lymphocytes. The expression levels of miR-126 and miR-21 in T lymphocytes were observed, as well as cytokine release and apoptosis. Finally, the association between miR-126, miR-21, cytokines and apoptosis in T lymphocytes was analyzed. The release of TNF-α and IL-6 in septic rats was initially elevated but then decreased. miR-126 and miR-21 levels in T lymphocytes in septic rats were lower than those of NC rats. miR-126 and miR-21 initially decreased and then increased, whereas of apoptosis of T lymphocytes increased and then decreased, in septic rats. The expression of miR-126 was positively correlated with that of miR-21 (r=0.316; P=0.029) and negatively correlated with that of TNF-α (r=-0.480; P=0.001) and IL-6 (r=-0.626; P<0.001), as well as the apoptotic rate of T lymphocytes (r=-0.377; P=0.008). Furthermore, expression levels of miR-126 were negatively corrlated with caspase-3 expression levels (r=-0.606; P<0.001) and activity (r=-0.541; P<0.001). There was a negative correlation between miR-21 and levels of TNF-α (r=-0.311; P=0.032) and IL-6 (r=-0.439; P=0.002), as well as caspase-3 expression (r=-0.398; P=0.005) and activity (r=-0.378; P=0.008). However, there miR-126 expression was not correlated with apoptotic rate of T lymphocytes. Altered expression levels of miR-126 and miR-21 reflected the severity of inflammatory response and indicated levels of T lymphocyte apoptosis in septic rats.

Functioning of Long Noncoding RNAs Expressed in Macrophage in the Development of Atherosclerosis

Chronic inflammation is part of the pathological process during atherosclerosis (AS). Due to the abundance of monocytes/macrophages within the arterial plaque, monocytes/macrophages have become a critical cellular target in AS studies. In recent decades, a number of long noncoding RNAs (lncRNAs) have been found to exert regulatory roles on the macrophage metabolism and macrophage plasticity, consequently promoting or suppressing atherosclerotic inflammation. In this review, we provide a comprehensive overview of lncRNAs in macrophage biology, highlighting the potential role of lncRNAs in AS based on recent findings, with the aim to identify disease biomarkers and future therapeutic interventions for AS.