Upregulation of miR145 and miR126 in EVs from Renal Cells Undergoing EMT and Urine of Diabetic Nephropathy Patients

Research progress on small extracellular vesicles in diabetic nephropathy

Virtually all cell types are capable of secreting small extracellular vesicles (sEV), which can be internalized by recipient cells, thereby serving as vehicles for intercellular communication. The cargoes of these vesicles, such as microRNAs, circular RNAs, proteins, and lipids, play significant roles in both normal cellular functions and the pathogenesis of various diseases. Diabetic Nephropathy (DN), a complication arising from diabetes, is expected to contribute to a 54% increase in the global diabetic population between 2015 and 2030, leading to substantial economic burdens on individuals and healthcare systems. sEVs, as promising biomarkers, demonstrate diverse mechanistic responses in different types of Diabetic Kidney Disease (DKD). They also hold advantages in the early prediction of renal damage. This article reviews the functional mechanisms of sEVs in DKD and their potential as therapeutic targets and biomarkers.

The role of exosomes in the pathogenesis and management of diabetic kidney disease: a systematic review and meta-analysis

Objective

This systematic review and meta-analysis aimed to synthesize the role of exosomes in the pathogenesis and management of diabetic kidney disease.

Methods

PubMed, Embase, Cochrane Library, and Web of Science were searched for studies that compared the levels of exosomes between patients with diabetic kidney disease and controls published up to 27 November 2023. Methodological quality was assessed using the JBI Appraisal Checklist for Case-Control Studies. The methodology of the samples and the main results were summarized. A meta-analysis of the diagnostic performance of exosomes was performed using estimates of test sensitivity and specificity, and these values were summarized using summary receiver-operating characteristic curves. The results were reported following the PRISMA 2020 checklist.

Results

A total of 32 studies, including 1,119 patients with diabetic kidney disease and 1,328 controls, met the inclusion criteria. A total of 78 upregulated and 22 downregulated microRNAs, 2 upregulated and 4 downregulated mRNAs, 6 upregulated and 1 downregulated proteins, and 4 upregulated lipids were identified. The miR-126, miR-145, miR-150, miR-21, and WT1 mRNA dysregulation were consistently reported in at least two studies. The overall sensitivity and specificity of the exosomes in diabetic kidney disease diagnosis were 0.70 (95% CI: 0.59-0.80) and 0.79 (95% CI: 0.70-0.85), respectively. The summary receiver operating characteristic curve was plotted to assess diagnostic accuracy with the area under the curve (AUC) of 0.82 (95% CI: 0.78-0.85).

Conclusion

Exosomes have great potential to become effective diagnostic biomarkers for diabetic kidney disease. Panels of exosomes or the combination of exosomes with other clinical indicators seemed more accurate than single exosomes.

Frontier role of extracellular vesicles in kidney disease

Kidney diseases represent a diverse range of conditions that compromise renal function and structure which characterized by a progressive deterioration of kidney function, may ultimately necessitate dialysis or kidney transplantation as end-stage treatment options. This review explores the complex landscape of kidney diseases, highlighting the limitations of existing treatments and the pressing need for innovative strategies. The paper delves into the role of extracellular vesicles (EVs) as emerging biomarkers and therapeutic agents in the context of kidney pathophysiology. Urinary extracellular vesicles (uEVs), in particular, offer a non-invasive means of assessing renal injury and monitoring disease progression. Additionally, mesenchymal stem cell-derived EVs (MSC-EVs) are examined for their immunomodulatory and tissue repair capabilities, presenting a promising avenue for novel therapeutic interventions. And discusses the potential of engineering EVs to enhance their targeting and therapeutic efficacy. This paper systematically integrates the latest research findings and aims to provide a comprehensive overview of the role of EVs in kidney disease, providing cutting-edge insights into their potential as a diagnostic and therapeutic tool.

Kidney Cancer and Potential Use of Urinary Extracellular Vesicles

Kidney cancer is the 14th most common cancer globally. The 5-year relative survival rate of kidney cancer at a localized stage is 92.9% and it declines to 17.4% in metastatic stage. Currently, the most accurate method of its diagnosis is tissue biopsy. However, the invasive and costly nature of biopsies makes it undesirable in many patients. Therefore, novel biomarkers for diagnosis and prognosis should be explored. Urinary extracellular vesicles (uEVs) are small vesicles (50-200 nm) in urine carrying nucleic acids, proteins and lipids as their cargos. These uEVs' cargos can provide non-invasive alternative to monitor kidney health. In this review, we have summarized recent studies investigating potential use of uEVs' cargos as biomarkers in kidney cancer for diagnosis, prognosis and therapeutic intervention.

Advances in the Pathogenesis of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is both a frequent complication of diabetes mellitus (DM) [...].

MicroRNA-126 in dogs with immune complex-mediated glomerulonephritis

BACKGROUND

Most proteinuric dogs with naturally occurring chronic kidney disease have amyloidosis (AMYL), glomerulosclerosis (GS), or immune complex-mediated glomerulonephritis (ICGN), each with different treatment and prognosis. A noninvasive and disease-specific biomarker is lacking.

HYPOTHESIS

We hypothesized that the expression pattern of biofluid microRNA (miRNAs and miRs) would correlate with disease progression and categorization.

ANIMALS

Archived serum and urine samples from 18 dogs with glomerular disease and 6 clinically healthy dogs; archived urine samples from 49 dogs with glomerular disease and 13 clinically healthy dogs.

METHODS

Retrospective study. Archived biofluid samples from adult dogs with biopsy-confirmed glomerular disease submitted to the International Veterinary Renal Pathology Service between 2008 and 2016 were selected. Serum and urinary miRNAs were isolated and profiled using RNA sequencing. Urinary miR-126, miR-21, miR-182, and miR-486 were quantified using quantitative reverse transcription PCR.

RESULTS

When comparing more advanced disease with earlier disease, no serum miRNAs were differentially expressed, but urinary miR-21 and miR-182 were 1.63 (95% CI: .86-3.1) and 1.45 (95% CI: .82-2.6) times higher in azotemic dogs, respectively (adjusted P < .05) and weakly correlated with tubulointerstitial fibrosis (miR-21: r = .32, P = .03; miR-182: r = .28, P = .05). Expression of urinary miR-126 was 10.5 (95% CI: 4.1-26.7), 28.9 (95% CI: 10.5-79.8), and 126.2 (95% CI: 44.7-356.3) times higher in dogs with ICGN compared with dogs with GS, AMYL, and healthy controls, respectively (P < .001).

CONCLUSIONS AND CLINICAL IMPORTANCE

The miR-126 could help identify dogs that might benefit from immunosuppressive therapy in the absence of a biopsy. MiR-21 and miR-182 are potential markers of disease severity and fibrosis.

Exploring the role of urinary extracellular vesicles in kidney physiology, aging, and disease progression

Extracellular vesicles (EVs), membranous vesicles present in all body fluids, are considered important messengers, carrying their information over long distance and modulating the gene expression profile of recipient cells. EVs collected in urine (uEVs) are mainly originated from the apical part of urogenital tract, following the urine flow. Moreover, bacterial-derived EVs are present within urine and may reflect the composition of microbiota. Consolidated evidence has established the involvement of uEVs in renal physiology, being responsible for glomerular and tubular cross talk and among different tubular segments. uEVs may also be involved in other physiological functions such as modulation of innate immunity, coagulation, or metabolic activities. Furthermore, it has been recently remonstrated that age, sex, endurance excise, and lifestyle may influence uEV composition and release, modifying their cargo. On the other hand, uEVs appear modulators of different urogenital pathological conditions, triggering disease progression. uEVs sustain fibrosis and inflammation processes, both involved in acute and chronic kidney diseases, aging, and stone formation. The molecular signature of uEVs collected from diseased patients can be of interest for understanding kidney physiopathology and for identifying diagnostic and prognostic biomarkers.

Identification of urinary extracellular vesicles differentially expressed RNAs in diabetic nephropathy via whole-transcriptome integrated analysis

BACKGROUND

Diabetic nephropathy (DN) is a common systemic microvascular complication of diabetes and a leading cause of chronic kidney disease worldwide. Urinary extracellular vesicles (uEVs), which are natural nanoscale vesicles that protect RNA from degradation, have the potential to serve as an invasive diagnostic biomarker for DN.

METHODS

We enrolled 24 participants, including twelve with renal biopsy-proven T2DN and twelve with T2DM, and isolated uEVs using ultracentrifugation. We performed microarrays for mRNAs, lncRNAs, and circRNAs in parallel, and Next-Generation Sequencing for miRNAs. Differentially expressed RNAs (DE-RNAs) were subjected to CIBERSORTx, ssGSEA analysis, GO enrichment, PPI network analysis, and construction of the lncRNA/circRNA-miRNA-mRNA regulatory network. Candidate genes and potential biomarker RNAs were validated using databases and machine learning models.

RESULTS

A total of 1684 mRNAs, 126 lncRNAs, 123 circRNAs and 66 miRNAs were found in uEVs in T2DN samples compared with T2DM. CIBERSORTx revealed the involvement of uEVs in immune activity and ssGSEA explored possible cell or tissue sources of uEVs. A ceRNA co-expression and regulation relationship network was constructed. Candidate genes MYO1C and SP100 mRNA were confirmed to be expressed in the kidney using Nephroseq database, scRNA-seq dataset, and Human Protein Atlas database. We further selected 2 circRNAs, 2 miRNAs, and 2 lncRNAs from WGCNAs and ceRNAs and demonstrated their efficacy as potential diagnostic biomarkers for T2DN using machine learning algorithms.

CONCLUSIONS

This study reported, for the first time, the whole-transcriptome genetic resources found in urine extracellular vesicles of T2DN patients. The results provide additional support for the possible interactions, and regulators between RNAs from uEVs themselves and as potential biomarkers in DN.

Rapid purification and multiparametric characterization of circulating small extracellular vesicles utilizing a label-free lab-on-a-chip device

Nano-scale extracellular vesicles are lipid-bilayer delimited particles that are naturally secreted by all cells and have emerged as valuable biomarkers for a wide range of diseases. Efficient isolation of small extracellular vesicles while maintaining yield and purity is crucial to harvest their potential in diagnostic, prognostic, and therapeutic applications. Most conventional methods of isolation suffer from significant shortcomings, including low purity or yield, long duration, need for large sample volumes, specialized equipment, trained personnel, and high costs. To address some of these challenges, our group has reported a novel insulator-based dielectrophoretic device for rapid isolation of small extracellular vesicles from biofluids and cell culture media based on their size and dielectric properties. In this study, we report a comprehensive characterization of small extracellular vesicles isolated from cancer-patients' biofluids at a twofold enrichment using the device. The three-fold characterization that was performed using conventional flow cytometry, advanced imaging flow cytometry, and microRNA sequencing indicated high yield and purity of the isolated small extracellular vesicles. The device thus offers an efficient platform for rapid isolation while maintaining biomolecular integrity.

Rab3A/Rab27A System Silencing Ameliorates High Glucose-Induced Injury in Podocytes

Diabetic nephropathy is a major complication in diabetic patients. Podocytes undergo loss and detachment from the basal membrane. Intra- and intercellular communication through exosomes are key processes for maintaining function, and the Rab3A/Rab27A system is an important counterpart. Previously, we observed significant changes in the Rab3A/Rab27A system in podocytes under glucose overload, demonstrating its important role in podocyte injury. We investigated the implication of silencing the Rab3A/Rab27A system in high glucose-treated podocytes and analysed the effect on differentiation, apoptosis, cytoskeletal organisation, vesicle distribution, and microRNA expression in cells and exosomes. For this, we subjected podocytes to high glucose and transfection through siRNAs, and we isolated extracellular vesicles and performed western blotting, transmission electron microscopy, RT-qPCR, immunofluorescence and flow cytometry assays. We found that silencing RAB3A and RAB27A generally leads to a decrease in podocyte differentiation and cytoskeleton organization and an increase in apoptosis. Moreover, CD63-positive vesicles experienced a pattern distribution change. Under high glucose, Rab3A/Rab27A silencing ameliorates some of these detrimental processes, suggesting a differential influence depending on the presence or absence of cellular stress. We also observed substantial expression changes in miRNAs that were relevant in diabetic nephropathy upon silencing and glucose treatment. Our findings highlight the Rab3A/Rab27A system as a key participant in podocyte injury and vesicular traffic regulation in diabetic nephropathy.