MicroRNA-103a-3p enhances sepsis-induced acute kidney injury via targeting CXCL12

Analysis of key microRNA molecules associated with acute kidney injury based on bioinformatics method

RATIONALE

Acute kidney injury (AKI) is a critical condition with limited early detection biomarkers and therapeutic options. This study aims to identify differentially expressed genes and potential microRNAs (miRNAs) as detection and therapeutic targets for AKI using bioinformatics-based analysis.

PATIENT CONCERNS

The study focuses on AKI as a major health concern with a need for improved biomarkers to monitor and treat this condition effectively.

DIAGNOSES

The bioinformatics analysis was conducted on the Gene Expression Omnibus database to identify key differentially expressed genes related to AKI. Additionally, potential miRNAs associated with these genes were predicted to provide further insight into AKI diagnosis and therapeutic strategies.

INTERVENTIONS

Raw chip data from the Gene Expression Omnibus database were analyzed using coexpression complex analysis of weighted genes to identify differentially expressed genes associated with AKI. Gene set enrichment analysis and gene ontology analyses were performed to examine the pathways involved. A gene-miRNA regulatory network was constructed to explore potential therapeutic targets.

OUTCOMES

A total of 277 differentially expressed genes were identified, with 200 genes upregulated and 77 downregulated. Significant enrichment pathways included neuroactive ligand-receptor interactions, Leishmania infection, prion disease, and electrocardiogram receptor interactions. Key enriched pathways from the Kyoto Encyclopedia of Genes and Genomes included the cytokine receptor binding pathway, chemokine signaling pathway, phosphatidylinositol-3-kinase/protein kinase B signaling pathway, and nuclear transcription factor kappa B signaling pathway. Ten hub genes, namely intercellular adhesion molecule 1 (ICAM1), C-X-C chemokine ligand 8 (CXCL8), toll-like receptor 2 (TLR2), selectin L (SELL), cytotoxic T lymphocyte-associated antigen (CTLA4), cell differentiation antigen 69 (CD69), disaccharide proteoglycan (BGN), C-X-C chemokine ligand 13 (CXCL13), metalloproteinase inhibitor 1 (TIMP1), and chemokine receptor 4 (CXCR4), were identified. Twelve critical miRNAs, namely hsa-miR-335-5p, hsa-miR-92a-3p, hsa-miR-146a-5p, hsa-miR-155-5p, hsa-miR-4426, hsa-miR-26b-5p, hsa-miR-4462b, hsa-miR-4647, hsa-miR-32-5p, hsa-miR-92b-3p, hsa-miR-98-5p, and hsa-miR-93-5p, were also identified.

LESSONS

This bioinformatics analysis highlights 277 differentially expressed genes and 12 potential miRNAs that may serve as biomarkers for AKI detection and therapy. These findings contribute to a better understanding of the molecular mechanisms underlying AKI and offer promising targets for future diagnostic and therapeutic strategies.

Sepsis-Associated Acute Kidney Injury: What's New Regarding Its Diagnostics and Therapeutics?

Sepsis-associated acute kidney injury (SA-AKI) is defined as the development of AKI in the context of a potentially life-threatening organ dysfunction attributed to an abnormal immune response to infection. SA-AKI has been associated with increased mortality when compared to sepsis or AKI alone. Therefore, its early recognition is of the utmost importance in terms of its morbidity and mortality rates. The aim of this review is to shed light on the pathophysiological pathways implicated in SA-AKI as well as its diagnostics and therapeutics. In this review, we will elucidate upon serum and urinary biomarkers, such as creatinine, cystatin, neutrophil gelatinase-associated lipocalin (NGAL), proenkephalin A 119-159, interleukin-6, interleukin-8 and interleukin-18, soluble toll-like receptor 2 (sTLR2), chemokine ligand 2 (CCL2) and chemokine C-C-motif 14 (CCL14). In addition, the role of RNA omics as well as machine learning programs for the timely diagnosis of SA-AKI will be further discussed. Moreover, regarding SA-AKI treatment, we will elaborate upon potential therapeutic agents that are being studied, based on the pathophysiology of SA-AKI, in humans and in animal models.

miR-16-5p aggravates sepsis-associated acute kidney injury by inducing apoptosis

Sepsis-associated acute kidney injury (S-AKI) is a common disease in pediatric intensive care units (ICU) with high morbidity and mortality. The newly discovered results indicate that microRNAs (miRNAs) play an important role in the diagnosis and treatment of S-AKI and can be used as markers for early diagnosis. In this study, the expression level of miR-16-5p was found to be significantly upregulated about 20-fold in S-AKI patients, and it also increased by 1.9 times in the renal tissue of S-AKI mice. Receiver operating characteristic (ROC) curve analysis showed that miR-16-5p had the highest predictive accuracy in the diagnosis of S-AKI (AUC = 0.9188). In vitro, the expression level of miR-16-5p in HK-2 cells treated with 10 μg/mL lipopolysaccharide (LPS) increased by more than 2 times. In addition, LPS-exposed renal tissue and HK-2 cells lead to upregulation of inflammatory cytokines IL-6, IL-1β, TNF-a, and kidney damage molecules kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL). However, inhibition of miR-16-5p significantly mitigated LPS expose-mediated kidney injury and inflammation. Furthermore, LPS-exposed HK-2 cells increased more than 1.7-fold the expression levels of Bax and caspase-3, decreased 3.2-fold the expression level of B-cell lymphoma-2 (Bcl-2), and significantly promoted the occurrence of apoptosis. MiR-16-5p mimic further increased LPS-induced apoptosis in HK-2 cells. Nevertheless, inhibition of miR-16-5p significantly attenuated this effect. In summary, up-regulation of miR-16-5p expression can significantly aggravate renal injury and apoptosis in S-AKI, which also proves that miR-16-5p can be used as a potential biomarker to promote early identification of S-AKI.

Inhibition of sepsis-induced acute kidney injury via the circITCH-miR-579-3p-ZEB2 axis

Circular RNAs (circRNAs) are linked to the regulation of sepsis-induced acute kidney injury (AKI). However, the function of circITCH in the development of sepsis-induced AKI is still unclear. The levels of circITCH, miR-579-3p and ZEB2 were examined by real-time PCR and immunoblotting. Then, the roles of circITCH in cell viability, apoptosis, and inflammation in lipopolysaccharide (LPS)-treated HK-2 cells were evaluated. The further mechanism was investigated using rescue assays. CircITCH was downregulated in septic AKI patients and LPS-triggered HK-2 cells. CircITCH overexpression restored cell viability in LPS-treated HK-2 cells and restrained apoptosis and inflammatory cytokine production. CircITCH negatively regulated miR-579-3p, thereby upregulating ZEB2 expression. Taken together, circITCH alleviates LPS-induced HK-2 cell injury by regulating miR-579-3p/ZEB2 signal axis, which provides a theoretical basis for AKI therapy.

Vancomycin Induced Ferroptosis in Renal Injury Through the Inactivation of Recombinant Glutathione Peroxidase 4 and the Accumulation of Peroxides

Background

Vancomycin (VCM) has long been used clinically to fight against Gram-positive bacterial infections. In recent decades, an increased number of kidney injury cases caused by VCM overdose have been reported. In this study, we further investigated the mechanism of VCM-overdose-induced kidney injury.

Methods

Immunohistochemistry (IHC) staining, RT-qPCR and Western blot assays were used to determine ki67, DDX5, PTGS2, GPX4 and SLC7A11 expressions in the kidney tissues of mice. CCK-8 and flow cytometry assays were used to determine HK2 cell viability and apoptosis. In addition, RT-qPCR and Western blot assays was applied to evaluate the expressions of ACSL4, PTGS2, GPX4, SLC7A11, DDX5 and Ki67 in HK2 cells.

Results

We found that VCM induced ferroptosis in vitro and in vivo. Ferrostatin-1 (Fer-1) is a potent inhibitor of ferroptosis, Fer-1 rescued cell viability and renal function renal morphology in VCM-treated cells and mice, respectively. Further, GPX4, which plays an essential role in reducing lipid hydroperoxides and preventing ferroptosis, was observed to be downregulated by VCM treatment. Interestingly, we found that GPX4-knockdown HK-2 cells exhibited a similar phenotype and gene expression level of ACSL4, PTGS2, DDX5 and Ki67 compared with VCM-treated cells, which suggested that VCM could induce ferroptosis in HK2 cells by down-regulating GPX4.

Conclusion

In conclusion, VCM induced renal injury in the kidney tissues of mice. In addition, VCM induced ferroptosis cell death in HK-2 cells and in the kidney tissues of mice by down-regulating GPX4 and causing the accumulation of peroxides. These data suggested that VCM could induce renal injury in vitro and in vivo via triggering ferroptosis. This study further elucidates the mechanism of VCM-induced renal injury and provides additional references for clinical use of VCM.

Expression of MicroRNAs in Sepsis-Related Organ Dysfunction: A Systematic Review

Sepsis is a critical condition characterized by increased levels of pro-inflammatory cytokines and proliferating cells such as neutrophils and macrophages in response to microbial pathogens. Such processes lead to an abnormal inflammatory response and multi-organ failure. MicroRNAs (miRNA) are single-stranded non-coding RNAs with the function of gene regulation. This means that miRNAs are involved in multiple intracellular pathways and thus contribute to or inhibit inflammation. As a result, their variable expression in different tissues and organs may play a key role in regulating the pathophysiological events of sepsis. Thanks to this property, miRNAs may serve as potential diagnostic and prognostic biomarkers in such life-threatening events. In this narrative review, we collect the results of recent studies on the expression of miRNAs in heart, blood, lung, liver, brain, and kidney during sepsis and the molecular processes in which they are involved. In reviewing the literature, we find at least 122 miRNAs and signaling pathways involved in sepsis-related organ dysfunction. This may help clinicians to detect, prevent, and treat sepsis-related organ failures early, although further studies are needed to deepen the knowledge of their potential contribution.