LncRNA CAIF suppresses LPS-induced inflammation and apoptosis of cardiomyocytes through regulating miR-16 demethylation

Columbianadin Ameliorates Myocardial Injury by Inhibiting Autophagy Through the PI3K/Akt/mTOR Signaling Pathway in AMI Mice and Hypoxic H9c2 Cells

Acute myocardial infarction (AMI) is a leading cause of mortality among cardiovascular diseases, yet effective therapies for AMI are limited. Previous studies have suggested cardioprotective effects of columbianadin (CBN), but its specific role in AMI and the underlying mechanisms remain unclear. This study aims to investigate whether CBN influences AMI and to elucidate the underlying mechanisms. We conducted a network pharmacology analysis to investigate the relationship between CBN and AMI. The AMI model was established by ligating the left anterior descending (LAD) artery in C57BL/6J mice, which were subsequently administered CBN. Hypoxic H9c2 cells were utilized to evaluate the effects of CBN in vitro. Our study revealed that CBN treatment significantly reduced myocardial infarction in AMI mice. It enhanced mitochondrial function and suppressed autophagy flux in hypoxic H9c2 cells. Furthermore, CBN downregulated the expression of LC3, Beclin1, and Atg 5 genes and proteins. In response to CBN treatment, the phosphorylation levels of PI3K, Akt, and mTOR increased. Notably, RAPA attenuated the protective effect of CBN in enhancing the survival of hypoxic H9c2 cells and abolished its regulation of autophagy-related proteins via the PI3K/Akt/mTOR signaling pathway. In conclusion, CBN reduces myocardial damage by suppressing autophagy via the PI3K/Akt/mTOR signaling pathway in AMI mice and hypoxic H9c2 cells.

Role of gasotransmitters in necroptosis

Gasotransmitters are endogenous gaseous signaling molecules that can freely pass through cell membranes and transmit signals between cells, playing multiple roles in cell signal transduction. Due to extensive and ongoing research in this field, we have successfully identified many gasotransmitters so far, among which nitric oxide, carbon monoxide, and hydrogen sulfide are best studied. Gasotransmitters are implicated in various diseases related to necroptosis, such as cardiovascular diseases, inflammation, ischemia-reperfusion, infectious diseases, and neurological diseases. However, the mechanisms of their effects on necroptosis are not fully understood. This review focuses on endogenous gasotransmitter synthesis and metabolism and discusses their roles in necroptosis, aiming to offer new insights for the therapeutic approaches to necroptosis-associated diseases.

Apoptosis and long non-coding RNAs: Focus on their roles in Heart diseases

Heart disease is one of the principal death reasons around the world and there is a growing requirement to discover novel healing targets that have the potential to avert or manage these illnesses. On the other hand, apoptosis is a strongly controlled, cell removal procedure that has a crucial part in numerous cardiac problems, such as reperfusion injury, MI (myocardial infarction), consecutive heart failure, and inflammation of myocardium. Completely comprehending the managing procedures of cell death signaling is critical as it is the primary factor that influences patient mortality and morbidity, owing to cardiomyocyte damage. Indeed, the prevention of heart cell death appears to be a viable treatment approach for heart illnesses. According to current researches, a number of long non-coding RNAs cause the heart cells death via different methods that are embroiled in controlling the activity of transcription elements, the pathways that signals transmission within cells, small miRNAs, and the constancy of proteins. When there is too much cell death in the heart, it can cause problems like reduced blood flow, heart damage after restoring blood flow, heart disease in diabetics, and changes in the heart after reduced blood flow. Therefore, studying how lncRNAs control apoptosis could help us find new treatments for heart diseases. In this review, we present recent discoveries about how lncRNAs are involved in causing cell death in different cardiovascular diseases.

Revealing Landscape of Competing Endogenous RNA Networks in Sepsis-Induced Cardiovascular Diseases

Cardiovascular dysfunction induced by sepsis is one of the most common phenotypes of cardiovascular diseases (CVDs), which is closely related to the high mortality of sepsis and is an urgent health problem to be solved worldwide. Unfortunately, the exact pathogenesis and pathophysiology of sepsis-induced cardiovascular dysfunction are not clear. As a research hotspot in recent years, competing endogenous RNA (ceRNA) networks are involved in the modulation of the pathophysiological progression of many diseases, including sepsis-related CVDs. Both long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) can specifically bind to microRNAs (miRNAs) as ceRNAs to target messenger RNAs (mRNAs), forming a ceRNA network composed of lncRNA/circRNA-miRNA-mRNA. This review demonstrates the potential regulatory mechanism of the ceRNA networks in sepsis-induced cardiovascular toxicity, hoping to provide novel therapeutic strategies and monitoring targets for sepsis-related CVDs.

Extracellular Vesicles from Campylobacter jejuni CDT-Treated Caco-2 Cells Inhibit Proliferation of Tumour Intestinal Caco-2 Cells and Myeloid U937 Cells: Detailing the Global Cell Response for Potential Application in Anti-Tumour Strategies

Cytolethal distending toxin (CDT) is produced by a range of Gram-negative pathogenic bacteria such as Campylobacter jejuni. CDT represents an important virulence factor that is a heterotrimeric complex composed of CdtA, CdtB, and CdtC. CdtA and CdtC constitute regulatory subunits whilst CdtB acts as the catalytic subunit exhibiting phosphatase and DNase activities, resulting in cell cycle arrest and cell death. Extracellular vesicle (EV) secretion is an evolutionarily conserved process that is present throughout all kingdoms. Mammalian EVs play important roles in regular cell-to-cell communications but can also spread pathogen- and host-derived molecules during infections to alter immune responses. Here, we demonstrate that CDT targets the endo-lysosomal compartment, partially evading lysosomal degradation and exploiting unconventional secretion (EV release), which is largely involved in bacterial infections. CDT-like effects are transferred by Caco-2 cells to uninfected heterologous U937 and homologous Caco-2 cells. The journey of EVs derived from CDT-treated Caco-2 cells is associated with both intestinal and myeloid tumour cells. EV release represents the primary route of CDT dissemination, revealing an active toxin as part of the cargo. We demonstrated that bacterial toxins could represent suitable tools in cancer therapy, highlighting both the benefits and limitations. The global cell response involves a moderate induction of apoptosis and autophagic features may play a protective role against toxin-induced cell death. EVs from CDT-treated Caco-2 cells represent reliable CDT carriers, potentially suitable in colorectal cancer treatments. Our data present a potential bacterial-related biotherapeutic supporting a multidrug anticancer protocol.

Tumor cell-derived exosomal lncRNA LOC441178 inhibits the tumorigenesis of esophageal carcinoma through suppressing macrophage M2 polarization

Esophageal carcinoma (EC) is a highly malignant type of tumor. In a previous study, the authors found that long non-coding RNA (lncRNA) LOC441178 inhibited the tumorigenesis of EC. Moreover, exosomes derived from tumor cells containing lncRNAs were found to play a key role in the tumor environment; however, whether exosomes can affect the tumor microenvironment by carrying LOC441178 remains unclear. Thus, the present study aimed to clarify this. In order to assess the effects of exosomal LOC441178 in EC, cell invasion and migration were examined using the Transwell assay. Exosomes were identified using transmission electron microscopy, Western blot analysis and nanoparticle tracking analysis. Furthermore, macrophage surface makers (CD206 and CD86) were analyzed using flow cytometry. Moreover, a subcutaneous xenograft mouse model was constructed to assess the role of TE-9 cells-derived exosomal LOC441178 in EC. The results revealed that LOC441178 overexpression notably suppressed the metastasis of EC cells. In addition, exosomes were successfully isolated from EC cells, and LOC441178 level was upregulated in exosomes derived from LOC441178- overexpressed EC cells. Exosomal LOC441178 also suppressed macrophage M2 polarization, and the polarized macrophages decreased EC cell invasion. Exosomes containing LOC441178 notably inhibited the growth of EC in mice. On the whole, the present study demonstrated that the delivery of LOC441178 by EC cell-secreted exosomes inhibited the tumorigenesis of EC by suppressing the polarization of M2 macrophages. These findings may provide a new theoretical basis for discovering new strategies against EC.

Identification and validation of autophagy-related genes in exogenous sepsis-induced acute respiratory distress syndrome

OBJECTIVE

To analyze the differential expression of autophagy-related genes of sepsis-induced acute respiratory distress syndrome (ARDS) as potential markers for early diagnosis.

METHODS

Male Sprague-Dawley rats (aged 8 weeks) were selected and randomly divided into sepsis-induced ARDS group (n = 6) and a normal control group (n = 6). Lung tissue samples were collected for high-throughput sequencing using Illumina HiSeq sequencing platform in the paired-end sequencing mode. Differentially expressed genes (DEGs) were screened by DESeq. 2 software [|log2FC | ≥1 and p < .05] and autophagy-related genes were identified using Mouse Genome Informatics. Co-expressed autophagy-related DEGs from these two datasets were filtered by construction of a Venn diagram. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed on these autophagy-related DEGs and a protein interaction network was constructed using STRING and Cytoscape software to identify hub genes, which were verified by real-time quantitative polymerase chain reaction (qRT-PCR).

RESULTS

A total of 42 autophagy-related DEGs (26 upregulated genes and 16 downregulated genes) were identified. The GO and KEGG pathway analyses showed enrichment in 969 biological processes (BPs), three cellular components (CCs), eight molecular functions (MFs) and 27 signaling pathways. The protein interaction (PPI) network revealed 42 node proteins and 75 interacting edges, with an average node degree of 3.52, and an average local clustering coefficient of 0.509. Among the top 10 hub genes with the RNA-Seq, six hub genes (Stat3, Il10, Ifng, Hmox1, Hif1a, and Nod2) were validated by qRT-PCR (all p < .05).

CONCLUSION

42 potential autophagy-related genes associated with sepsis-induced ARDS lung injury were identified and six hub genes (Stat3, Il10, Ifng, Hmox1, Hif1a, and Nod2) may affect the development of ARDS by regulating autophagy. These results expanded our understanding of ARDS and might be useful in treatment of exogenous sepsis-induced ARDS.

Long Non-Coding RNA HOTTIP is Elevated in Patients with Sepsis and Promotes Cardiac Dysfunction

BACKGROUND

Cardiac dysfunction is the most common clinical complication of sepsis. Herein, the study explored the clinical importance of long non-coding RNA (lncRNA) HOXA terminal transcript antisense RNA (HOTTIP) in the onset of sepsis and the development of cardiac dysfunction.

METHODS

120 patients with sepsis were recruited and divided into cardiac dysfunction group and non-cardiac dysfunction group. Serum HOTTIP levels were measured via RT-qPCR. AC16 cells were treated with lipopolysaccharide (LPS) for cell experiments and detected for cell viability and apoptosis.

RESULTS

High serum HOTTIP levels were tested in sepsis patients, which was associated with procalcitonin (PCT) level. Serum HOTTIP can identify sepsis cases from healthy people with the AUC of 0.927. 72 cases developed into cardiac dysfunction, accompanied by elevated levels of HOTTIP. ROC curve displayed the predictive ability of serum HOTTIP in the development of cardiac dysfunction in patients with sepsis. After adjusting for other clinical parameters, HOTTIP can independently affect the development of cardiac dysfunction. In vitro, HOTTIP knockdown promoted the recovery of cell viability and reversed LPS-induced cell apoptosis and excessive interleukin-6 (IL-6) release.

CONCLUSION

LncRNA HOTTIP is closely related to the condition of patients with sepsis and the development of cardiac dysfunction, possibly owing to its function in LPS-induced myocardial apoptosis and inflammation.

Molecular mechanism of CAIF inhibiting myocardial infarction by sponging miR‑488 and regulating AVEN expression

In recent years, the global incidence and mortality of myocardial infarction (MI) has increased and become one of the important diseases threatening public health. Long non-coding (lnc)RNAs are a type of ncRNA that serve critical roles in the progression of various types of disease. The present study aimed to investigate the effect and mechanism of lncRNA cardiac autophagy inhibitory factor (CAIF) on cardiac ischemia/reperfusion (I/R) injury. CAIF was downregulated in the myocardium of I/R rats and cardiomyocytes treated with hydrogen peroxide (H₂O₂). Further experiments demonstrated that CAIF overexpression inhibited I/R-induced cardiac infarction and apoptosis in vivo. CAIF decreased H₂O₂-induced apoptosis and oxidative stress of cardiomyocytes. Mechanistically, CAIF sponged microRNA (miR)-488-5p; this interaction was confirmed by rescue experiments. Moreover, miR-488-5p targeted apoptosis and caspase activation inhibitor (AVEN) and inhibited its expression. In summary, the present data identified a novel CAIF/miR-488-5p/AVEN signaling axis as a key regulator of myocyte apoptosis, which may be a potential therapeutic target for the treatment of MI.

Non-coding RNA-based regulation of inflammation

Inflammation is a multifactorial process and various biological mechanisms and pathways participate in its development. The presence of inflammation is involved in pathogenesis of different diseases such as diabetes mellitus, cardiovascular diseases and even, cancer. Non-coding RNAs (ncRNAs) comprise large part of transcribed genome and their critical function in physiological and pathological conditions has been confirmed. The present review focuses on miRNAs, lncRNAs and circRNAs as ncRNAs and their potential functions in inflammation regulation and resolution. Pro-inflammatory and anti-inflammatory factors are regulated by miRNAs via binding to 3'-UTR or indirectly via affecting other pathways such as SIRT1 and NF-κB. LncRNAs display a similar function and they can also affect miRNAs via sponging in regulating levels of cytokines. CircRNAs mainly affect miRNAs and reduce their expression in regulating cytokine levels. Notably, exosomal ncRNAs have shown capacity in inflammation resolution. In addition to pre-clinical studies, clinical trials have examined role of ncRNAs in inflammation-mediated disease pathogenesis and cytokine regulation. The therapeutic targeting of ncRNAs using drugs and nucleic acids have been analyzed to reduce inflammation in disease therapy. Therefore, ncRNAs can serve as diagnostic, prognostic and therapeutic targets in inflammation-related diseases in pre-clinical and clinical backgrounds.

LncRNA CAIF suppresses LPS-induced inflammation and apoptosis of cardiomyocytes through regulating miR-16 demethylation

BACKGROUND

The long noncoding RNA, cardiac autophagy inhibitory factor (CAIF), and microRNA (miR)-16 are reported to be involved in lipopolysaccharide (LPS)-induced inflammatory responses and cell apoptosis in many diseases. Herein, we investigated the interaction between CAIF and miR-16 in sepsis-induced chronic heart failure (CHF).

METHODS

The expression of CAIF and miR-16 in plasma samples from sepsis-induced CHF patients (n = 60) and healthy controls (n = 60) were measured using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The correlations between CAIF and miR-16 across plasma samples from patients with sepsis-induced CHF and healthy controls were analyzed using linear regression. The messenger RNA (mRNA) levels of inducible nitric oxide synthase, C-C motif chemokine 2 (CCL2), growth-regulated alpha protein (CXCL1), and interleukin-6 (IL-6) were evaluated using qRT-PCR while nuclear factor κB activation was evaluated using luciferase assay.

RESULTS

The expression levels of CAIF and miR-16 were downregulated in the plasma of sepsis-induced CHF patients and were positively correlated in these patients. In cardiomyocytes, LPS treatment dose-dependently decreased CAIF and miR-16 levels. CAIF overexpression increased miR-16 expression by demethylating miR-16. CAIF and/or miR-16 overexpression suppressed LPS-induced CCL2, CXCL1, and IL-6 expression at both the mRNA and protein levels. Analysis of cell apoptosis and western blot analysis showed that CAIF and/or miR-16 overexpression inhibited LPS-induced cardiomyocyte apoptosis by reducing Bax and cleaved caspase 3 levels and enhancing Bcl-2 levels.

CONCLUSION

Our study is the first to report the abnormal expression of CAIF and miR-16 in heart disease. CAIF plays a protective role in sepsis-induced CHF by inhibiting cardiomyocyte apoptosis and inflammation, possibly by regulating miR-16 demethylation.