Co-expression analysis reveals dysregulated miRNAs and miRNA-mRNA interactions in the development of contrast-induced acute kidney injury

MicroRNAs in acute kidney injury

Acute kidney injury (AKI) is a clinical syndrome with high morbidity and mortality. AKI has emerged as a significant global public health issue, particularly among hospitalized patients, with the highest incidence observed in those admitted to intensive care units (ICUs). However, early diagnosis of AKI remains challenging due to the limited sensitivity and specificity of conventional biomarkers, including serum creatinine and urine output. Recently, microRNAs (miRNAs) have garnered increasing interest for their potential in the early detection and management of AKI. Owing to their high stability, ease of quantification, well-characterized regulatory functions, and close association with key pathophysiological processes, miRNAs are considered promising diagnostic and therapeutic candidates. Nevertheless, the clinical utility of miRNAs remains limited by confounding factors such as co-infections, comorbidities, and medication use, which may lead to false-positive results. Challenges also persist regarding off-target effects and developing safe and efficient delivery systems. Furthermore, only a few studies have systematically characterized miRNA expression profiles in AKI, considering its heterogeneous etiologies and the dynamic nature of miRNA regulation. Interactions between miRNAs and between miRNAs and non-coding RNAs such as circular (circRNAs) and long non-coding RNAs (lncRNAs) warrant further investigation.

Signal pathways involved in contrast-induced acute kidney injury

Contrast-induced acute kidney injury (CI-AKI) has emerged as a global public health concern, ranking as the third most prevalent cause of hospital-acquired acute kidney injury, which is related to adverse outcomes. However, its precise pathogenesis remains elusive. Consequently, researchers are dedicated to uncovering CI-AKI's pathophysiology and signaling pathways, including inflammation, oxidative stress, apoptosis, and ferroptosis, to improve prevention and treatment. This review thoroughly analyzes the signaling pathways and their interactions associated with CI-AKI, assesses the impact of various research models on pathway analysis, and explores more precise targeted treatment and prevention approaches. Aims to furnish a robust theoretical foundation for the molecular mechanisms underpinning clinical treatments.

Enhancing Pseudomonas syringae pv. Actinidiae sensitivity in kiwifruit by repressing the NBS-LRR genes through miRNA-215-3p and miRNA-29-3p identification

Kiwifruit bacterial canker, caused by Pseudomonas syringae pv. actinidiae (PSA), poses a grave threat to the global kiwifruit industry. In this study, we examined the role of microRNAs (miRNAs) in kiwifruit's response to PSA. Kiwifruit seedlings subjected to PSA treatment showed significant changes in both miRNA and gene expression compared to the control group. We identified 364 differentially expressed miRNAs (DEMs) and 7170 differentially expressed genes (DEGs). Further analysis revealed 180 miRNAs negatively regulating 641 mRNAs. Notably, two miRNAs from the miRNA482 family, miRNA-215-3p and miRNA-29-3p, were found to increase kiwifruit's sensitivity to PSA when overexpressed. These miRNAs were linked to the regulation of NBS-LRR target genes, shedding light on their role in kiwifruit's defence against PSA. This study offers insights into the miRNA482-NBS-LRR network as a crucial component in enhancing kiwifruit bioresistance to PSA infestation and provides promising candidate genes for further research.

Rapidly Blocking the Calcium Overload/ROS Production Feedback Loop to Alleviate Acute Kidney Injury via Microenvironment-Responsive BAPTA-AM/BAC Co-Delivery Nanosystem

Calcium overload and ROS overproduction, two major triggers of acute kidney injury (AKI), are self-amplifying and mutually reinforcing, forming a complicated cascading feedback loop that induces kidney cell "suicide" and ultimately renal failure. There are currently no clinically effective drugs for the treatment of AKI, excluding adjuvant therapy. In this study, a porous silicon-based nanocarrier rich in disulfide bond skeleton (<50 nm) is developed that enables efficient co-loading of the hydrophilic drug borane amino complex and the hydrophobic drug BAPTA-AM, with its outer layer sealed by the renal tubule-targeting peptide PEG-LTH. Once targeted to the kidney injured site, the nanocarrier structure collapses in the high glutathione environment of the early stage of AKI, releasing the drugs. Under the action of the slightly acidic inflammatory environment and intracellular esterase, the released drugs produce hydrogen and BAPTA, which can rapidly eliminate the excess ROS and overloaded Ca²⁺ , blocking endoplasmic reticulum/mitochondrial apoptosis pathway (ATF4-CHOP-Bax axis, Casp-12-Casp-3 axis, Cyt-C-Casp-3 axis) and inflammatory pathway (TNF-α-NF-κB axis) from the source, thus rescuing the renal cells in the "critical survival" state and further restoring the kidney function. Overall, this nanoparticle shows substantial clinical promise as a potential therapeutic strategy for I/R injury-related diseases.

Endothelial Progenitor Cells Affect the Growth and Apoptosis of Renal Cells by Secreting Microvesicles Carrying Dysregulated miR-205 and miR-206

Background

This study investigated the mechanism of microRNA (miRNA, miR) in microvesicles (MVs) secreted by endothelial progenitor cells (EPCs) involved in renal function in vivo and in vitro injury repair of rat primary kidney cells (PRKs).

Methods

Gene Expression Omnibus analysis of potential target miRNAs in nephrotic rats. Real-time quantitative polymerase chain reaction verified the correlation of these miRNAs and screened the effective target miRNAs and their downstream putative target mRNAs. Western blot analyzes the protein levels of DEAD-box helicase 5 (DDX5) and the activation of the proapoptotic factor caspase-3/9 (cleaved). Dil-Ac-LDL staining, immunofluorescence, and a transmission electron microscope (TEM) were used to identify the successful isolation of EPCs and PRKs and the morphology of MVs. Cell Counting Kit-8 was used to detect the effect of miRNA-mRNA on the proliferation of PRKs. Standard biochemical kits were used to detect biochemical indicators in rat blood and urine. Dual-luciferase analysis of miRNA binding to mRNA was conducted. The effect of miRNA-mRNA interaction on the apoptosis level of PRKs was analyzed by flow cytometry.

Results

A total of 13 rat-derived miRNAs were potential therapeutic targets, and miR-205 and miR-206 were screened as the targets of this study. We found that the EPC-MVs alleviated the increase of blood urea nitrogen and urinary albumin excretion and the decrease in creatinine clearance caused by hypertensive nephropathy in vivo. The effect of MVs in improving renal function indicators was promoted by miR-205 and miR-206 and inhibited by knockdown of expressed miR-205 and miR-206. In vitro, angiotensin II (Ang II) promoted growth inhibition and apoptosis of PRKs, and similarly, dysregulated miR-205 and miR-206 affected the induction of Ang II. We then observed that miR-205 and miR-206 cotargeted the downstream target DDX5 and regulated its transcriptional activity and translational levels, while also reducing the activation of proapoptotic factors caspase-3/9. Overexpressed DDX5 reversed the effects of miR-205 and miR-206.

Conclusion

By upregulating the expression of miR-205 and miR-206 in MVs secreted by EPC, the transcriptional activity of DDX5 and the activation of caspase-3/9 can be inhibited, thereby promoting the growth of PRKs and protecting the injury caused by hypertensive nephropathy.

Regulation of mitophagy through HIF-1α/miR-140-5p/PARKIN axis in acute kidney injury

Mitochondria homeostasis plays an important role in acute kidney injury (AKI). In this study, we aimed at identifying the mechanism of mitophagy regulation in AKI. Activation of mitophagy after ischemic kidney injury was visualized with increased expression of LC3, PINK1, PARKIN expression and with a subsequent decline in p62 levels. Immuohistochemistry staining showed higher LC3 levels in ischemic kidney injury mice. Further, differential expression of PARKIN targeting miRNAs revealed that miR-140-5p was significantly downregulated followed by ischemic kidney injury. miR-140-5p mimics suppressed PARKIN expressions and their mitochondrial translocation. Further, miR-140-5p mimics under hypoxia prevented mitophagosome formation. These effects on hypoxia-induced PARKIN expression and LC3/TOMM20 levels were reversed by antagomiR miR-140-5p treatment. Dual-luciferase reporter assay revealed that miR-140-5p had significant interaction with 3'UTR of PARKIN. Our findings show that HIF-1α is bound to miR-140-5p promoter and down regulates its expression and thereby promotes mitophagy process under hypoxic conditions. These results cumulatively show that HIF-1α regulates mitophagy during AKI through the regulation of miR-140-5p/PARKIN axis.

Recent findings on the role of microRNAs in genetic kidney diseases

BACKGROUND

MicroRNAs (miRNAs) are non-coding, endogenous, single-stranded, small (21-25 nucleotides) RNAs. Various target genes at the post-transcriptional stage are modulated by miRNAs that are involved in the regulation of a variety of biological processes such as embryonic development, differentiation, proliferation, apoptosis, inflammation, and metabolic homeostasis. Abnormal miRNA expression is strongly associated with the pathogenesis of multiple common human diseases including cardiovascular diseases, cancer, hepatitis, and metabolic diseases.

METHODS AND RESULTS

Various signaling pathways including transforming growth factor-β, apoptosis, and Wnt signaling pathways have also been characterized to play an essential role in kidney diseases. Most importantly, miRNA-targeted pharmaceutical manipulation has represented a promising new therapeutic approach against kidney diseases. Furthermore, miRNAs such as miR-30e-5p, miR-98-5p, miR-30d-5p, miR-30a-5p, miR-194-5p, and miR-192-5p may be potentially employed as biomarkers for various human kidney diseases.

CONCLUSIONS

A significant correlation has also been found between some miRNAs and the clinical markers of renal function like baseline estimated glomerular filtration rate (eGFR). Classification of miRNAs in different genetic renal disorders may promote discoveries in developing innovative therapeutic interventions and treatment tools. Herein, the recent advances in miRNAs associated with renal pathogenesis, emphasizing genetic kidney diseases and development, have been summarized.

Comprehensive analysis of the long non-coding RNA expression profile and functional roles in a contrast-induced acute kidney injury rat model

Long non-coding RNAs (lncRNAs) have been identified as a class of regulatory RNAs that participate in both physiological and pathological conditions, including acute kidney injury. However, the roles of lncRNA dysregulation in the pathogenesis of contrast-induced acute kidney injury (CI-AKI) are largely unknown. In the present study, the expression profiles of lncRNAs in kidney tissue were compared between rats with CI-AKI and controls using high-throughput RNA sequencing. In total, 910 differentially expressed (DE) lncRNAs (DElncRNAs), including 415 downregulated and 495 upregulated lncRNAs, were identified at 12 h after intra-arterial iodinated contrast medium injection (fold change ≥2; P<0.05). Eight DElncRNAs were further selected and validated using reverse transcription-quantitative polymerase chain reaction. A previous study defined microRNA (miRNA) and mRNA expression changes in the same CI-AKI model. In the present study, a lncRNA-mRNA co-expression network comprising 349 DElncRNAs and 202 DEmRNAs was constructed. The function of these DElncRNAs was mainly associated with oxidative stress and inflammation. Additionally, lncRNA-associated competing endogenous RNA (ceRNA) analysis revealed a network comprising 40 DElncRNA nodes, 5 DEmiRNA nodes and 59 DEmRNA nodes. Among which, the carnosine dipeptidase 1-specific and the transmembrane protein 184B-specific networks were likely to be associated with CI-AKI. The results of the present study revealed the expression profile and potential roles of lncRNAs in CI-AKI, and provide a framework for further mechanistic studies.

Biochemical Markers in the Prediction of Contrast-induced Acute Kidney Injury

For many years clinicians have been searching for "kidney troponin"- a simple diagnostic tool to assess the risk of acute kidney injury (AKI). Recently, the rise in the variety of contrast-related procedures (contrast computed tomography (CT), percutaneous coronary intervention (PCI) and angiography) has resulted in the increased number of contrast-induced acute kidney injuries (CI-AKI). CIAKI remains an important cause of overall mortality, prolonged hospitalisation and it increases the total costs of therapy. The consequences of kidney dysfunction affect the quality of life and they may lead to disability as well. Despite extensive worldwide research, there are no sensitive and reliable methods of CI-AKI prediction. Kidney Injury Molecule 1 (KIM-1) and Neutrophil Gelatinase Lipocalin (NGAL) have been considered as kidney-specific molecules. High concentrations of these substances before the implementation of contrast-related procedures have been suggested to enable the estimation of kidney vulnerability to CI-AKI and they seem to have the predictive potential for cardiovascular events and overall mortality. According to other authors, routine determination of known inflammation factors (e.g., CRP, WBC, and neutrophil count) may be helpful in the prediction of CIAKI. However, the results of clinical trials provide contrasting results. The pathomechanism of contrast- induced nephropathy remains unclear. Due to its prevalence, the evaluation of the risk of acute kidney injury remains a serious problem to be solved. This paper reviews pathophysiology and suggested optimal markers facilitating the prediction of contrast-induced acute kidney injury.

MicroRNA as an early diagnostic biomarker for contrast-induced acute kidney injury

Contrast-induced acute kidney injury (CI-AKI) is a common clinical complication and an important cause of increased mortality, prolonged hospitalization, and increased medical costs. For taking effective interventions in CI-AKI, early diagnosis and active prevention are of key importance. Currently, early CI-AKI detection depends on serum creatinine (Scr) levels, which lags behind the actual time of renal injury and seriously affects early diagnosis and interventions. MicroRNA (miRNA) has been found to be a useful biomarker in early CI-AKI diagnosis. Several studies have reported on tissue and time-specific miRNAs in AKI as effective diagnostic biomarkers and potential therapeutic targets, but there are only a few studies on miRNA in CI-AKI. However, these studies are preliminary exploratory investigations on changes in miRNA expression in CI-AKI, and whether these specific miRNAs can be used as biomarkers for early CI-AKI diagnosis and as clinical therapeutic targets requires systematic and in-depth studies. Therefore, more sensitive and specific miRNAs of CI-AKI could be discovered, providing newer options and development directions for early diagnosis and intervention in clinical CI-AKI practice. This review evaluates the research progress on specific miRNAs in the early diagnosis of CI-AKI with an aim of providing basic data for the clinical application of these molecular markers in CI-AKI.

AdipoRon, an adiponectin receptor agonist, protects contrast-induced nephropathy by suppressing oxidative stress and inflammation via activation of the AMPK pathway

BACKGROUND

Contrast-induced nephropathy (CIN), a complication caused by using contrast medium during diagnostic and interventional procedures, occurs frequently and lacks effective treatment. AdipoRon, the agonist of adiponectin receptors, has been shown to benefit many organs including the kidney. This study aimed to investigate the role of AdipoRon in treating CIN.

METHODS

CIN model was established via infusing iopromide (1.8 g/kg) in Sprague-Dawley (SD) rats; NRK52E cells were treated with iopromide (5-50 μM). Renal function, renal histopathology, levels of lactate dehydrogenase (LDH) release, cell vitality, oxidative stress and inflammatory markers were measured to evaluate the protective effects of AdipoRon. The level of pAMPK/AMPK was determined by western blot.

RESULTS

AdipoRon (50 mg/kg) significantly reversed serum creatinine, blood urea nitrogen, creatinine clearance and urinary kidney injury molecule-1 levels induced by iopromide in SD rats. Besides, it decreased the renal injury score and apoptosis of renal cells. AdipoRon also reversed the changes of antioxidant markers, pro-oxidant and inflammatory markers induced by iopromide. Moreover, the in vitro studies showed that AdipoRon decreased LDH release and increased cell vitality in NRK52E cells treated with iopromide. Then, we demonstrated that the protection of AdipoRon was accompanied by augmented AMPK phosphorylation. Both in vivo and in vitro studies demonstrated that compound c, an AMPK inhibitor, reversed the AdipoRon-mediated improvement in the CIN model.

CONCLUSION

Our data indicate that AdipoRon protects against the CIN by suppressing oxidative stress and inflammation via activating the AMPK pathway, showing that AdipoRon might be a potential candidate for the prevention and therapy of CIN.

The Role of MicroRNA in Contrast-Induced Nephropathy: A Scoping Review and Meta-Analysis

OBJECTIVE

Early diagnosis of contrast-induced nephropathy (CIN) remains crucial for successful treatment; unfortunately, the widely used serum creatinine is elevated only in the late stage of CIN. The circulating microRNAs (miRNAs) are stable biomarker that might be useful. The aim of this scoping review and meta-analysis is to assess the role of miRNAs in CIN.

METHODS

We performed a systematic literature search on topics that assess the role of miRNAs in CIN from several electronic databases.

RESULTS

There were 6 preclinical studies and 2 of them validated their findings in human. Only miR-30a, miR-30c, miR-30e, and miR-188 have been validated in human models. Meta-analysis showed that increase in miR-30a expression was associated with higher incidence of CIN (OR 4.48 [1.52, 13.26],  p = 0.007; I 2: 94%, p < 0.001). An increase in miR-30e expression was associated with higher incidence of CIN (OR 2.34 [1.70, 3.20], p < 0.001; I 2: 0%, p = 0.76). There is an indication that miR-188 is associated with contrast-induced apoptosis and might potentially be a drug target in the future.

CONCLUSION

This study highlighted the importance of certain miRNAs in CIN pathophysiology. Future researches should explore on the prognostic and therapeutic implication of miRNA in CIN.