Expression of urinary exosomal miRNA-615-3p and miRNA-3147 in diabetic kidney disease and their association with inflammation and fibrosis

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.

Engineered Nanoparticles for Theranostic Applications in Kidney Repair

Kidney diseases are characterized by their intricate nature and complexity, posing significant challenges in their treatment and diagnosis. Nanoparticles (NPs), which can be further classified as synthetic and biomimetic NPs, have emerged as promising candidates for treating various diseases. In recent years, the development of engineered nanotherapeutics has focused on targeting damaged tissues and serving as drug delivery vehicles. Additionally, these NPs have shown superior sensitivity and specificity in diagnosis and imaging, thus providing valuable insights for the early detection of diseases. This review aims to focus on the application of engineered synthetic and biomimetic NPs in kidney diseases in the aspects of treatment, diagnosis, and imaging. Notably, the current perspectives and challenges are evaluated, which provide inspiration for future research directions, and encourage the clinical application of NPs in this field.

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.

Research progress on the role of extracellular vesicles in the pathogenesis of diabetic kidney disease

Diabetic kidney disease (DKD) is a serious complication of diabetes mellitus (DM) and has become the main cause of end-stage renal disease worldwide. In recent years, with the increasing incidence of DM, the pathogenesis of DKD has received increasing attention. The pathogenesis of DKD is diverse and complex. Extracellular vesicles (EVs) contain cell-derived membrane proteins, nucleic acids (such as DNA and RNA) and other important cellular components and are involved in intercellular information and substance transmission. In recent years, an increasing number of studies have confirmed that EVs play an important role in the development of DKD. The purpose of this paper is to explain the potential diagnostic value of EVs in DKD, analyze the mechanism by which EVs participate in intercellular communication, and explore whether EVs may become drug carriers for targeted therapy to provide a reference for promoting the implementation and application of exosome therapy strategies in clinical practice.

Alterations in the Levels of Urinary Exosomal MicroRNA-183-5p and MicroRNA-125a-5p in Individuals with Type 2 Diabetes Mellitus

Background: Type 2 diabetes mellitus (T2DM) is a metabolic disorder, and urinary exosomal microRNAs (miRNAs) were utilized as potential disease prediction or diagnostic biomarkers in numerous studies. This study investigated the differential expression of urinary exosomal miRNAs between non-diabetes mellitus (NDM) individuals and those with T2DM. Aim: To elucidate the association between urinary exosomal miRNAs and T2DM. Methods: We recruited patients diagnosed with T2DM and NDM individuals in West China Hospital, Sichuan University, from November 2023 to February 2024. Subsequently, we performed sequencing of urinary exosomal microRNAs in both groups. The obtained sequencing results were further validated using RT-qPCR in both the training set and the validation set. Additionally, we conducted logistic regression analysis and Spearman correlation analysis on miRNAs with significant differential expression, as well as analysis of their biological functions. Results: A total of 118 urine samples were collected, 59 from individuals diagnosed with T2DM and 59 from NDM. There were differentially expressed miR-183-5p (p = 0.034) and miR-125a-5p (p = 0.008) between the two groups. Furthermore, multivariate regression analysis demonstrated that higher miR-125a-5p levels were negatively associated with the risk of T2DM (p = 0.044; OR: 0.046; 95% CI: 0.002, 0.922). Bioinformatics analysis indicated that the target genes of miR-183-5p were predominantly involved in insulin signaling and glucose transport processes, while those target genes of miR-125a-5p primarily mediated autophagy. Conclusions: miR-183-5p and miR-125a-5p might be involved in the pathogenesis of T2DM, while higher urinary exosomal miR-125a-5p was negatively associated with the risk of T2DM.

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.

The mineralocorticoid receptor in diabetic kidney disease

Diabetes mellitus is one of the leading causes of chronic kidney disease and its progression to end-stage kidney disease (ESKD). Diabetic kidney disease (DKD) is characterized by glomerular hypertrophy, hyperfiltration, inflammation, and the onset of albuminuria, together with a progressive reduction in glomerular filtration rate. This progression is further accompanied by tubulointerstitial inflammation and fibrosis. Factors such as genetic predisposition, epigenetic modifications, metabolic derangements, hemodynamic alterations, inflammation, and inappropriate renin-angiotensin-aldosterone system (RAAS) activity contribute to the onset and progression of DKD. In this context, decades of work have focused on glycemic and blood pressure reduction strategies, especially targeting the RAAS to slow disease progression. Although much of the work has focused on targeting angiotensin II, emerging data support that the mineralocorticoid receptor (MR) is integral in the development and progression of DKD. Molecular mechanisms linked to the underlying pathophysiological changes derived from MR activation include vascular endothelial and epithelial cell responses to oxidative stress and inflammation. These responses lead to alterations in the microcirculatory environment, the abnormal release of extracellular vesicles, gut dysbiosis, epithelial-mesenchymal transition, and kidney fibrosis. Herein, we present recent experimental and clinical evidence on the MR in DKD onset and progress along with new MR-based strategies for the treatment and prevention of DKD.

Role of Extracellular Vesicle-Derived Noncoding RNAs in Diabetic Kidney Disease

Background

Diabetic kidney disease (DKD), a metabolism-related syndrome characterized by abnormal glomerular filtration rate, proteinuria, and renal microangiopathy, is one of the most common forms of chronic kidney disease, whereas extracellular vesicles (EVs) have been recently evidenced as a novel cell communication player in DKD occurrence and progress via releasing various bioactive molecules, including proteins, lipids, and especially RNA, among which noncoding RNAs (including miRNAs, lncRNAs, and circRNAs) are the major regulators. However, the functional relevance of EV-derived ncRNAs in DKD is to be elucidated.

Summary

Studies have reported that EV-derived ncRNAs regulate gene expression via a diverse range of regulatory mechanisms, contributing to diverse phenotypes related to DKD progression. Furthermore, there are already many potential clinical diagnostic and therapeutic studies based on these ncRNAs, which can be expected to have potential applications in clinical practice for EV-derived ncRNAs.

Key Messages

In the current review, we summarized the mechanistic role of EVs in DKD according to biological function classifications, including inflammation and oxidative stress, epithelial-mesenchymal transition, cell death, and extracellular matrix deposition. In addition, we comprehensively discussed the potential applications of EV-derived ncRNAs as diagnostic biomarkers and therapeutic targets in DKD.

The Expression of miR-377-3p in Patients with DKD and the Regulatory Mechanism of miR-377-3p on the Inflammatory Response of HK-2 Cells Through TGF-β

Objective

The purpose of the study was to investigate the expression levels and correlation of inflammatory factors such as miR-377-3p and TGF-β in patients with diabetic kidney disease (DKD), and to investigate the regulatory mechanism of transfection of miR-377-3p on the inflammatory response of HK-2 cell induced by high glucose.

Methods

According to UACR, patients were divided into normal albuminuria group (Con, n = 29), microalbuminuria group (Micro, n = 31) and macroalbuminuria group (Macro, n = 30), analyzed the correlation and influencing factors between DKD and inflammatory factor. HK-2 cells were randomly divided into four groups: normal control group (NC), high glucose group (HG), miR-377-3p overexpression group (MIN), and miR-377-3p inhibition group (IN). After transfection of miR-377-3p mimics and inhibitors, the contents of TGF-β, IL-6 and IL-18 were detected by RT-PCR and Western blot.

Results

The levels of miR-377-3p, TGF-β, IL-6 and IL-18 in both Micro group and Macro group were significantly higher than those in Con group (P < 0.05); Pearson correlation analysis showed that miR-377-3p was positively correlated with UACR, TG, TGF-β, IL-6 and IL-18, and negatively correlated with GFR (P < 0.05). Cell experiment: RT-PCR and Western blot results showed that miR-377-3p, TGF-β, IL-6 and IL-18 in HG group were significantly higher than those in NC group (P < 0.05). After transfection with miR-377-3p inhibitor, the levels of miR-377-3p, TGF-β, IL-6 and IL-18 in IN group were significantly decreased compared with HG group and MIN group.

Conclusion

miR-377-3p expression was elevated both in serum of DKD patients and in HK-2 cells with high glucose induced injury, overexpression of miR-377-3p exacerbates the damage to HK-2 cells and promotes the progression of DKD. Silencing miR-377-3p can potentially regulate the levels of inflammatory factors in HK-2 cells by targeting downregulation of TGF-β expression, thereby mitigating the damage to HK-2 cells and delaying the development of diabetic kidney disease.

Role of Epigenetic Changes in the Pathophysiology of Diabetic Kidney Disease

Background

Diabetic kidney disease (DKD) is a global health issue. Epigenetic changes play an important role in the pathogenesis of this disease.

Summary

DKD is currently the leading cause of kidney failure worldwide. Although much is known about the pathophysiology of DKD, the research field of epigenetics is relatively new. Several recent studies have demonstrated that diabetes-induced dysregulation of epigenetic mechanisms alters the expression of pathological genes in kidney cells. If these changes persist for a long time, the so-called "metabolic memory" could be established. In this review, we highlight diabetes-induced epigenetic modifications associated with DKD. While there is a substantial amount of literature on epigenetic changes, only a few studies describe the underlying molecular mechanisms. Detailed analyses have shown that epigenetic changes play an important role in known pathological features of DKD, such as podocyte injury, fibrosis, accumulation of extracellular matrix, or oxidative injury, all of which contribute to the pathophysiology of disease. The transforming growth factor-β plays a key role as it is involved in all-mentioned epigenetic types of regulation.

Key Messages

Epigenetic is crucial for the development and progression of DKD, but the detailed molecular mechanisms have to be further analyzed more in detail.

Urinary-derived extracellular vesicle microRNAs as non-invasive diagnostic biomarkers for early-stage renal cell carcinoma

BACKGROUND AND AIMS

The potential of urinary-derived extracellular vesicle (uEV) microRNAs (miRNAs) as noninvasive molecular biomarkers for identifying early-stage renal cell carcinoma (RCC) patients is rarely explored. The present study aims to explore the possibility of uEV miRNAs as novel molecular biomarkers for distinguishing early-stage RCC.

MATERIALS AND METHODS

uEVs were extracted by ExoQuick-TC™ kit and miRNA concentrations were measured by RT-qPCR. ROC curves and bioinformatics analysis were employed to predict the diagnostic efficacy and regulatory mechanisms of dysregulated miRNAs.

RESULTS

Through a multiphase case-control study on uEV miRNAs screening, training, and validation in RCC cells (ACHN, Caki-1) and control cells (HK-2) and in uEVs of 125 RCC patients and 128 age- and sex-matched controls, we successfully identified four uEVs miRNAs (miR-135b-5p, miR-196b-5p, miR-200c-3p, and miR-203a-3p) were significantly and stably upregulated in RCC in vitro and in vivo. When adjusted with estimated glomerular filtration rate (eGFR), the AUC of the three-uEV miRNA panel (miR-135b-5p, miR-200c-3p, and miR-203a-3p) was 0.785 (95 % CI = 0.729-0.842, P < 0.0001) for discriminating RCC patients from controls. Notably, this panel exhibited similar performance in distinguishing early-stage (stage Ⅰ) RCC patients, with an AUC of 0.786 (95 %CI = 0.727-0.844, P < 0.0001). Bioinformatics analysis predicted that candidate miRNAs were involved in cancer progressing.

CONCLUSION

Our study identified a four uEV miRNAs panel (miR-135b-5p, miR-196b-5p, miR-200c-3p, and miR-203a-3p) may serve as an auxiliary noninvasive indication of early-stage RCC.

Nanocarrier-Mediated Delivery of MicroRNAs for Fibrotic Diseases

MicroRNAs (miRNAs) are endogenous noncoding RNAs that mediate the fibrotic process by regulating multiple targets. MicroRNA-based therapy can restore or inhibit miRNA expression and is expected to become an effective approach to prevent and alleviate fibrotic diseases. However, the safe, targeted, and effective delivery of miRNAs is a major challenge in translating miRNA therapy from bench to bedside. In this review, we briefly describe the pathophysiological process of fibrosis and the mechanism by which miRNAs regulate the progression of fibrosis. Additionally, we summarize the miRNA nanodelivery tools for fibrotic diseases, including chemical modifications and polymer-based, lipid-based, and exosome-based delivery systems. Further clarification of the role of miRNAs in fibrosis and the development of a novel nanodelivery system may facilitate the prevention and alleviation of fibrotic diseases in the future.

Applicability of mesenchymal stem cell-derived exosomes as a cell-free miRNA therapy and epigenetic modifiers for diabetes

Given that exosome nanovesicles constitute various growth factors, miRNAs and lncRNAs, they have implications for epigenetic modifications. Few studies have shown that exosomes from mesenchymal stem cells (MSCs) exhibit therapeutic effects on diabetic complications by substituting miRNAs and regulating histone modifications. Therefore, reversing epigenetic aberrations in diabetes may provide new insight into its treatment. This review discusses the impact of DNA and histone methylations on the development of diabetes and its complications. Further, we talk about miRNAs dysregulated in diabetic conditions and the possibility of utilizing mesenchymal stem cell (MSC) exosomes for the development of miRNA cell-free therapy and epigenetic modifiers in reversing diabetic-induced epigenetic alterations.

Extracellular vesicle-mediated interorgan communication in metabolic diseases

The body partially maintains metabolic homeostasis through interorgan communication between metabolic organs under physiological conditions. This crosstalk is known to be mediated by hormones or metabolites, and has recently been expanding to include extracellular vesicles (EVs). EVs participate in interorgan communication under physiological and pathological conditions by encapsulating various bioactive cargoes, including proteins, metabolites, and nucleic acids. In this review we summarize the latest findings about the metabolic regulation of EV biogenesis, secretion, and components, and highlight the biological role of EV cargoes in interorgan communication in cancer, obesity, diabetes, and cardiovascular disease. We also discuss the potential application of EVs as diagnostic markers, and corresponding therapeutic strategies by EV engineering for both early detection and treatment of metabolic disorders.