Mesenchymal Stem Cell-Derived Exosomes Carry MicroRNA-125a to Protect Against Diabetic Nephropathy by Targeting Histone Deacetylase 1 and Downregulating Endothelin-1

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.

Beneficial effects of cell-derived exosomes on diabetic nephropathy: a systematic review and meta-analysis of preclinical evidence

AIMS

Recent studies indicate that cell-derived exosomes are effective in treating diabetic renal injury, though their precise mechanisms remain unclear. This meta-analysis evaluates the therapeutic efficacy of exosomes in diabetic nephropathy.

METHODS

In addition to reviewing references and consulting experts, we systematically searched PubMed, Cochrane Library, EMBASE, and Web of Science for studies on exosome therapy for diabetic nephropathy. Seven outcome measures were selected to evaluate efficacy: blood glucose [(fasting blood glucose (FBG) and random blood glucose (RBG)], renal function parameters [serum creatinine (SCR), blood urea nitrogen (BUN), 24-hour urinary protein (24 h UP) and albumin-to-creatinine ratio (UACR)], and inflammatory factors. Study quality was assessed using the SYRCLE risk of bias tool, and data were analyzed using RevMan (version 5.3) software.

RESULTS

We included 17 studies involving 288 animals, with follow-up durations ranging from 2 to 14 weeks. Pooled analysis demonstrated that exosome treatment significantly improved GLU (FBG: SMD - 1.39, 95% CI -2.70 to -0.08, P = 0.04; RBG: SMD - 1.29, 95% CI -2.25 to -0.34, P < 0.008), SCR (SMD - 1.45, 95% CI -2.14 to -0.76, P < 0.0001), BUN (SMD - 2.06, 95% CI -3.01 to -1.11, P < 0.0001), 24 UP (SMD - 2.88, 95% CI -3.97 to -1.78, P < 0.00001), and UACR (SMD - 2.00, 95% CI -3.15 to -0.85, P = 0.0007) compared to the diabetic model group. Qualitative analysis revealed that exosomes increased anti-inflammatory factors while reducing pro-inflammatory factors (P < 0.05). No adverse effects of exosomes were reported in any of the included studies.

CONCLUSIONS

Current evidence indicates that exosomes attenuate diabetic nephropathy progression through anti-inflammatory, anti-fibrotic, anti-apoptotic, and autophagy-inducing mechanisms. To demonstrate the most efficient exosomes and therapeutic parameters for the treatment of diabetic nephropathy, future studies should conduct sizable, randomized, double-blind trials with high-quality, long-term follow-ups.

Mesenchymal Stem Cell Therapy: Therapeutic Opportunities and Challenges for Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease (ESRD), which severely affects the quality of patients' lives. However, the current therapeutic approaches can only postpone its progression to ESRD. It is therefore imperative to develop a novel therapeutic strategy for renal injury in DKD, with the objective of restoring renal function and reversing the process of ESRD. In recent years, the potential of mesenchymal stem cell (MSC) therapy for DKD has garnered increasing attention within the scientific community. Preclinical research on MSC therapy has yielded promising results, and the safety of MSC treatment in vivo has been substantiated in clinical studies. An increasing body of evidence suggests that MSC therapy has significant potential for the treatment of DKD. This article reviews the existing research on MSCs and their derived exosomes in treating DKD and analyzes the underlying mechanism of MSC-based therapy for DKD. Additionally, we discuss the potential of combining MSC therapy with conventional pharmacological treatments, along with the constraints and prospects of MSC therapy for DKD. We hope this review can provide a precise and comprehensive understanding of MSCs for the treatment of DKD.

Molecular Therapeutics for Diabetic Kidney Disease: An Update

Diabetic kidney disease (DKD) is a common microvascular complication of diabetes mellitus (DM). With the increasing prevalence of DM worldwide, the incidence of DKD remains high. If DKD is not well controlled, it can develop into chronic kidney disease or end-stage renal disease (ESRD), which places considerable economic pressure on society. Traditional therapies, including glycemic control, blood pressure control, blood lipid control, the use of renin-angiotensin system blockers and novel drugs, such as sodium-glucose cotransporter 2 inhibitors, mineralocorticoid receptor inhibitors and glucagon-like peptide-1 receptor agonists, have been used in DKD patients. Although the above treatment strategies can delay the progression of DKD, most DKD patients still ultimately progress to ESRD. Therefore, new and multimodal treatment methods need to be explored. In recent years, researchers have continuously developed new treatment methods and targets to delay the progression of DKD, including miRNA therapy, stem cell therapy, gene therapy, gut microbiota-targeted therapy and lifestyle intervention. These new molecular therapy methods constitute opportunities to better understand and treat DKD. In this review, we summarize the progress of molecular therapeutics for DKD, leading to new treatment strategies.

Exendin-4-enriched exosomes from hUCMSCs alleviate diabetic nephropathy via gut microbiota and immune modulation

Introduction

Diabetic nephropathy (DN) presents a significant therapeutic challenge, compounded by complex pathophysiological mechanisms. Recent studies suggest Exendin-4 (Ex-4) as a potential ameliorative agent for DN, albeit with unclear mechanisms. This research investigates the effects and underlying mechanisms of Ex-4-enriched exosomes derived from human umbilical cord mesenchymal stem cells (hUCMSCs) on DN, focusing on their renoprotective properties and interactions with gut microbiota.

Method

Exosomes from hUCMSCs (hUCMSCs-Exo) were loaded with Ex-4 via electroporation. A streptozotocin (STZ) -induced DN mouse model was employed to assess the therapeutic impact of these engineered exosomes. The study further explored immune cell dynamics, mainly CD4+ regulatory T (Treg) cells, using bioinformatics, flow cytometry, and the influence of gut microbiota through antibiotic treatment and specific bacterial reintroduction.

Results

Treatment with hUCMSCs-Exo@Ex-4 significantly improved key DN markers, including blood glucose and proteinuria, alleviating kidney damage. A notable decrease in natural Treg cell infiltration in DN was observed, while Ex-4-loaded exosomes promoted CD4+ Treg cell induction. The therapeutic benefits of hUCMSCs-Exo@Ex-4 were diminished upon CD4+ Treg cell depletion, underscoring their role in this context. Notably, CD4+ Treg cell induction correlated with the presence of Prevotella species, and disruption of gut microbiota adversely affected these cells and the therapeutic efficacy of the treatment. However, the reintroduction of Prevotella strains counteracted these adverse effects.

Discussion

This study elucidates a novel therapeutic mechanism of Ex-4-loaded hUCMSCs exosomes in DN, highlighting the induction of CD4+ Treg cells mediated by specific gut microbiota components. These findings underscore the potential of leveraging gut microbiota and immune cell interplay in developing effective DN treatments.

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.

Exosomes derived from umbilical cord-derived mesenchymal stem cells exposed to diabetic microenvironment enhance M2 macrophage polarization and protect against diabetic nephropathy

The role of mesenchymal-stem-cell-derived exosomes (MSCs-Exo) in the regulation of macrophage polarization has been recognized in several diseases. There is emerging evidence that MSCs-Exo partially prevent the progression of diabetic nephropathy (DN). This study aimed to investigate whether exosomes secreted by MSCs pre-treated with a diabetic environment (Exo-pre) have a more pronounced protective effect against DN by regulating the balance of macrophages. Exo-pre and Exo-Con were isolated from the culture medium of UC-MSCs pre-treated with a diabetic mimic environment and natural UC-MSCs, respectively. Exo-pre and Exo-Con were injected into the tail veins of db/db mice three times a week for 6 weeks. Serum creatinine and serum urea nitrogen levels, the urinary protein/creatinine ratio, and histological staining were used to determine renal function and morphology. Macrophage phenotypes were analyzed by immunofluorescence, western blotting, and quantitative reverse transcription polymerase chain reaction. In vitro, lipopolysaccharide-induced M1 macrophages were incubated separately with Exo-Con and Exo-pre. We performed microRNA (miRNA) sequencing to identify candidate miRNAs and predict their target genes. An miRNA inhibitor was used to confirm the role of miRNAs in macrophage modulation. Exo-pre were more potent than Exo-Con at alleviating DN. Exo-pre administration significantly reduced the number of M1 macrophages and increased the number of M2 macrophages in the kidney compared to Exo-Con administration. Parallel outcomes were observed in the co-culture experiments. Moreover, miR-486-5p was distinctly expressed in Exo-Con and Exo-pre groups, and it played an important role in macrophage polarization by targeting PIK3R1 through the PI3K/Akt pathway. Reducing miR-486-5p levels in Exo-pre abolished macrophage polarization modulation. Exo-pre administration exhibited a superior effect on DN by remodeling the macrophage balance by shuttling miR-486-5p, which targets PIK3R1.

Renoprotective effect of a novel combination of 6-gingerol and metformin in high-fat diet/streptozotocin-induced diabetic nephropathy in rats via targeting miRNA-146a, miRNA-223, TLR4/TRAF6/NLRP3 inflammasome pathway and HIF-1α

BACKGROUND

MiRNA-146a and miRNA-223 are key epigenetic regulators of toll-like receptor 4 (TLR4)/tumor necrosis factor-receptor-associated factor 6 (TRAF6)/NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome pathway, which is involved in diabetic nephropathy (DN) pathogenesis. The currently available oral anti-diabetic treatments have been insufficient to halt DN development and progression. Therefore, this work aimed to assess the renoprotective effect of the natural compound 6-gingerol (GR) either alone or in combination with metformin (MET) in high-fat diet/streptozotocin-induced DN in rats. The proposed molecular mechanisms were also investigated.

METHODS

Oral gavage of 6-gingerol (100 mg/kg) and metformin (300 mg/kg) were administered to rats daily for eight weeks. MiRNA-146a, miRNA-223, TLR4, TRAF6, nuclear factor-kappa B (NF-κB) (p65), NLRP3, caspase-1, and hypoxia-inducible factor-1 alpha (HIF-1α) mRNA expressions were measured using real-time PCR. ELISA was used to measure TLR4, TRAF6, NLRP3, caspase-1, tumor necrosis factor-alpha (TNF-α), and interleukin-1-beta (IL-1β) renal tissue levels. Renal tissue histopathology and immunohistochemical examination of fibronectin and NF-κB (p65) were performed.

RESULTS

6-Gingerol treatment significantly reduced kidney tissue damage and fibrosis. 6-Gingerol up-regulated miRNA-146a and miRNA-223 and reduced TLR4, TRAF6, NF-κB (p65), NLRP3, caspase-1, TNF-α, IL-1β, HIF-1α and fibronectin renal expressions. 6-Gingerol improved lipid profile and renal functions, attenuated renal hypertrophy, increased reduced glutathione, and decreased blood glucose and malondialdehyde levels. 6-Gingerol and metformin combination showed superior renoprotective effects than either alone.

CONCLUSION

6-Gingerol demonstrated a key protective role in DN by induction of miRNA-146a and miRNA-223 expression and inhibition of TLR4/TRAF6/NLRP3 inflammasome signaling. 6-Gingerol, a safe, affordable, and abundant natural compound, holds promise for use as an adjuvant therapy with metformin in diabetic patients to attenuate renal damage and stop the progression of DN.

Acrylamide-targeting renal miR-21a-5p/Fibrotic and miR122-5p/ inflammatory signaling pathways and the role of a green approach for nano-zinc detected via in silico and in vivo approaches

Introduction: Any disruption in renal function can have cascading effects on overall health. Understanding how a heat-born toxicant like acrylamide (ACR) affects kidney tissue is vital for realizing its broader implications for systemic health. Methods: This study investigated the ACR-induced renal damage mechanisms, particularly focusing on the regulating role of miR-21a-5p/fibrotic and miR-122-5p/inflammatory signaling pathways via targeting Timp-3 and TP53 proteins in an In silico preliminary study. Besides, renal function assessment, oxidative status, protein profile, and the expression of renal biomarkers (Timp-1, Keap-1, Kim-1, P53, TNF-α, Bax, and Caspase3) were assessed in a 60-day experiment. The examination was additionally extended to explore the potential protective effects of green-synthesized zinc oxide nanoparticles (ZNO-MONPs). A four-group experiment including control, ZNO-MONPs (10 mg/kg b.wt.), ACR (20 mg/kg b.wt.), and ZNO-MONPs + ACR was established encompassing biochemical, histological, and molecular levels. The study further investigated the protein-binding ability of ZNO and MONPs to inactivate caspase-3, Keap-1, Kim-1, and TNFRS-1A. Results: ZNO-MONPs significantly reduced ACR-induced renal tissue damage as evidenced by increased serum creatinine, uric acid, albumin, and oxidative stress markers. ACR-induced oxidative stress, apoptosis, and inflammationare revealed by biochemical tests, gene expression, and the presence of apoptotic nuclei microscopically. Also, molecular docking revealed binding affinity between ACR-BCL-2 and glutathione-synthetase, elucidating the potential mechanisms through which ACR induces renal damage. Notably, ZNO-MONPs revealed a protective potential against ACR-induced damage. Zn levels in the renal tissues of ACR-exposed rats were significantly restored in those treated with ACR + ZNO-MONPs. In conclusion, this study establishes the efficacy of ZNO-MONPs in mitigating ACR-induced disturbances in renal tissue functions, oxidative stress, inflammation, and apoptosis. The findings shed light on the potential renoprotective activity of green-synthesized nanomaterials, offering insights into novel therapeutic approaches for countering ACR-induced renal damage.

Role of MicroRNA in linking diabetic retinal neurodegeneration and vascular degeneration

Diabetic retinopathy is the major cause of blindness in diabetic patients, with limited treatment options that do not always restore optimal vision. Retinal nerve degeneration and vascular degeneration are two primary pathological processes of diabetic retinopathy. The retinal nervous system and vascular cells have a close coupling relationship. The connection between neurodegeneration and vascular degeneration is not yet fully understood. Recent studies have found that microRNA plays a role in regulating diabetic retinal neurovascular degeneration and can help delay the progression of the disease. This article will review how microRNA acts as a bridge connecting diabetic retinal neurodegeneration and vascular degeneration, focusing on the mechanisms of apoptosis, oxidative stress, inflammation, and endothelial factors. The aim is to identify valuable targets for new research and clinical treatment of diabetic retinopathy.

Navigating the tumor microenvironment: mesenchymal stem cell-mediated delivery of anticancer agents

Scientific knowledge of cancer has advanced greatly throughout the years, with most recent studies findings includes many hallmarks that capture disease's multifaceted character. One of the novel approach utilised for the delivery of anti-cancer agents includes mesenchymal stem cell mediated drug delivery. Mesenchymal stem cells (MSCs) are non-haematopoietic progenitor cells that may be extracted from bone marrow, tooth pulp, adipose tissue and placenta/umbilical cord blood dealing with adult stem cells. MSCs are mostly involved in regeneration of tissue, they have also been shown to preferentially migrate to location of several types of tumour in-vivo. Usage of MSCs ought to improve both effectiveness and safety of anti-cancer drugs by enhancing delivery efficiency of anti-cancer therapies to tumour site. Numerous researches has demonstrated that various drugs, when delivered via mesenchymal stem cell mediated delivery can elicit anti-tumour effect of cells in cancers of breast cells and thyroid cells. MSCs have minimal immunogenicity because to lack of co-stimulatory molecule expression, which means there is no requirement for immunosuppression after allogenic transplantation. This current review elaborates recent advancements of mesenchyma stem cell mediated drug delivery of anti-cancer agents along with its mechanism and previously reported studies of drugs manufactured via this drug delivery system.

Therapeutic potential: The role of mesenchymal stem cells from diverse sources and their derived exosomes in diabetic nephropathy

Diabetic nephropathy (DN) is one of the most common microvascular complications in diabetic patients, with its incidence continuously increasing in recent years. DN causes renal tissue damage and functional decline, expedites the aging process of the kidneys, and may ultimately progress leading to end-stage renal disease, severely impacting the patient's quality of life and prognosis. Mesenchymal stem cells (MSCs) are highly valued for their multipotent differentiation, paracrine functions, immunomodulatory effects, and capacity for tissue repair. Particularly, exosomes (Exo) derived from MSCs (MSCs-Exo) are rich in bioactive molecules and facilitate intercellular communication, participating in various physiological and pathological processes. MSCs and MSCs-Exo, in particular, have been demonstrated to have therapeutic effects in DN treatment research by encouraging tissue repair, fibrosis inhibition, and inflammation reduction. Research has shown that MSCs and MSCs-Exo have therapeutic effects in DN treatment by promoting tissue repair, inhibiting fibrosis, and reducing inflammation. Recent studies underscore the potential of MSCs and MSCs-Exo, highlighting their broad applicability in DN treatment. This review aims to provide a comprehensive summary of the scientific developments in treating DN using MSCs and MSCs-Exo from diverse sources, while also exploring their future therapeutic possibilities in detail.

Emerging role of mesenchymal stem cell-derived exosome microRNA in radiation injury

PURPOSE

Radiation injury (RI) is a common occurrence in malignant tumors patients receiving radiation therapy. While killing tumor cells, normal tissue surrounding the target area is inevitably irradiated at a certain dose, which can cause varying results of radiation injury. Currently, there are limited clinical treatments available for radiation injuries. In recent years, the negative effects of stem cell therapy have been reported more clearly and non-cellular therapies such as exosomes have become a focus of attention for researchers. As a type of vesicle-like substances secreted by mesenchymal stem cells (MSC), MSC derived exosomes (MSC-exo) carry DNA, mRNA, microRNA (miRNAs), specific proteins, lipids, and other active substances involved in intercellular information exchange. miRNAs released by MSC-exo are capable of alleviating and repairing damaged tissues through anti-apoptosis, modulating immune response, regulating inflammatory response and promoting angiogenesis, which indicates that MSC-exo miRNAs have great potential for application in the prevention and treatment of radiation injury. Therefore, it is necessary to explore the underlying therapeutic mechanisms of MSC-exo miRNAs in this process, which may shed new lights on the treatment of radiation injury.

CONCLUSIONS

Increasing evidence confirms that MSC-exo has shown encouraging applications in tissue repair due to the anti-apoptotic, immunoreactive, and pro-angiogenesis effects of the miRNAs it carries as intercellular communication carriers. However, miRNA-based therapeutics are still in their infancy and many practical issues remain to be addressed for clinical applications.

Stem Cell-Derived Exosomal MicroRNAs as Novel Potential Approach for Multiple Sclerosis Treatment

Multiple Sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) characterized by inflammation and demyelination of CNS neurons. Up to now, there are many therapeutic strategies for MS but they are only being able to reduce progression of diseases and have not got any effect on repair and remyelination. Stem cell therapy is an appropriate method for regeneration but has limitations and problems. So recently, researches were used of exosomes that facilitate intercellular communication and transfer cell-to-cell biological information. MicroRNAs (miRNAs) are a class of short non-coding RNAs that we can used to their dysregulation in order to diseases diagnosis. The miRNAs of microvesicles obtained stem cells may change the fate of transplanted cells based on received signals of injured regions. The miRNAs existing in MSCs may be displayed the cell type and their biological activities. Current studies show also that the miRNAs create communication between stem cells and tissue-injured cells. In the present review, firstly we discuss the role of miRNAs dysregulation in MS patients and miRNAs expression by stem cells. Finally, in this study was confirmed the relationship of microRNAs involved in MS and miRNAs expressed by stem cells and interaction between them in order to find appropriate treatment methods in future for limit to disability progression.

The novel insights of epithelial-derived exosomes in various fibrotic diseases

The characteristics of fibrosis include the abnormal accumulation of extracellular matrix proteins and abnormal tissue repair caused by injury, infection, and inflammation, leading to a significant increase in organ failure and mortality. Effective and precise treatments are urgently needed to halt and reverse the progression of fibrotic diseases. Exosomes are tiny vesicles derived from endosomes, spanning from 40 to 160 nanometers in diameter, which are expelled into the extracellular matrix environment by various cell types. They play a crucial role in facilitating cell-to-cell communication by transporting a variety of cargoes, including proteins, RNA, and DNA. Epithelial cells serve as the primary barrier against diverse external stimuli that precipitate fibrotic diseases. Numerous research suggests that exosomes from epithelial cells have a significant impact on several fibrotic diseases. An in-depth comprehension of the cellular and molecular mechanisms of epithelial cell-derived exosomes in fibrosis holds promise for advancing the exploration of novel diagnostic biomarkers and clinical drug targets. In this review, we expand upon the pathogenic mechanisms of epithelium-derived exosomes and highlight their role in the fibrotic process by inducing inflammation and activating fibroblasts. In addition, we are particularly interested in the bioactive molecules carried by epithelial-derived exosomes and their potential value in the diagnosis and treatment of fibrosis and delineate the clinical utility of exosomes as an emerging therapeutic modality, highlighting their potential application in addressing various medical conditions.

Exosomes derived from mesenchymal stem cells in diabetes and diabetic complications

Diabetes, a group of metabolic disorders, constitutes an important global health problem. Diabetes and its complications place a heavy financial strain on both patients and the global healthcare establishment. The lack of effective treatments contributes to this pessimistic situation and negative outlook. Exosomes released from mesenchymal stromal cells (MSCs) have emerged as the most likely new breakthrough and advancement in treating of diabetes and diabetes-associated complication due to its capacity of intercellular communication, modulating the local microenvironment, and regulating cellular processes. In the present review, we briefly outlined the properties of MSCs-derived exosomes, provided a thorough summary of their biological functions and potential uses in diabetes and its related complications.

Efficacy of adipose-derived mesenchymal stem cell therapy in the treatment of chronic micro- and macrovascular complications of diabetes

Diabetes mellitus is a highly prevalent disease characterized by hyperglycaemia that damages the vascular system, leading to micro- (retinopathy, neuropathy, nephropathy) and macrovascular diseases (cardiovascular disease). There are also secondary complications of diabetes (cardiomyopathy, erectile dysfunction or diabetic foot ulcers). Stem cell-based therapies have become a promising tool targeting diabetes symptoms and its chronic complications. Among all stem cells, adipose-derived mesenchymal stem cells (ADMSCs) are of great importance because of their abundance, non-invasive isolation and no ethical limitations. Characteristics that make ADMSCs good candidates for cell-based therapy are their wide immunomodulatory properties and paracrine activities through the secretion of an array of growth factors, chemokines, cytokines, angiogenic factors and anti-apoptotic molecules. Besides, after transplantation, ADMSCs show great ex vivo expansion capacity and differentiation to other cell types, including insulin-producing cells, cardiomyocytes, chondrocytes, hepatocyte-like cells, neurons, endothelial cells, photoreceptor-like cells, or astrocytes. Preclinical studies have shown that ADMSC-based therapy effectively improved visual acuity, ameliorated polyneuropathy and foot ulceration, arrested the development and progression of diabetic kidney disease, or alleviated the diabetes-induced cardiomyocyte hypertrophy. However, despite the positive results obtained in animal models, there are still several challenges that need to be overcome before the results of preclinical studies can be translated into clinical applications. To date, there are several clinical trials or ongoing trials using ADMSCs in the treatment of diabetic complications, most of them in the treatment of diabetic foot ulcers. This narrative review summarizes the most recent outcomes on the usage of ADMSCs in the treatment of long-term complications of diabetes in both animal models and clinical trials.

Understanding exosomes: Part 2-Emerging leaders in regenerative medicine

Exosomes are the smallest subset of extracellular signaling vesicles secreted by most cells with the ability to communicate with other tissues and cell types over long distances. Their use in regenerative medicine has gained tremendous momentum recently due to their ability to be utilized as therapeutic options for a wide array of diseases/conditions. Over 5000 publications are currently being published yearly on this topic, and this number is only expected to dramatically increase as novel therapeutic strategies continue to be developed. Today exosomes have been applied in numerous contexts including neurodegenerative disorders (Alzheimer's disease, central nervous system, depression, multiple sclerosis, Parkinson's disease, post-traumatic stress disorders, traumatic brain injury, peripheral nerve injury), damaged organs (heart, kidney, liver, stroke, myocardial infarctions, myocardial infarctions, ovaries), degenerative processes (atherosclerosis, diabetes, hematology disorders, musculoskeletal degeneration, osteoradionecrosis, respiratory disease), infectious diseases (COVID-19, hepatitis), regenerative procedures (antiaging, bone regeneration, cartilage/joint regeneration, osteoarthritis, cutaneous wounds, dental regeneration, dermatology/skin regeneration, erectile dysfunction, hair regrowth, intervertebral disc repair, spinal cord injury, vascular regeneration), and cancer therapy (breast, colorectal, gastric cancer and osteosarcomas), immune function (allergy, autoimmune disorders, immune regulation, inflammatory diseases, lupus, rheumatoid arthritis). This scoping review is a first of its kind aimed at summarizing the extensive regenerative potential of exosomes over a broad range of diseases and disorders.

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.

Exosomal microRNAs: potential nanotherapeutic targets for diabetic kidney disease

Diabetic kidney disease (DKD) is a primary cause for end-stage renal disease, but no specific therapeutic approaches exist. Exosomal miRNAs, a key functional cargo of nanovesicles, play crucial roles in the pathophysiological processes of DKD. Exosomal miRNAs are involved in cell-to-cell transfer of biological information, mediating nephritic inflammation, oxidative stress, apoptosis, autophagy, epithelial-mesenchymal transition and fibrosis. Circulating exosomal miRNAs derived from urine or serum might function as noninvasive prognostic biomarkers for DKD. Exosomal miRNAs from stem cells have been reported to exert beneficial effects on diabetic kidneys, which suggests that these exosomes might function as potential nanotherapy tools for treating DKD. In this review, we have summarized recent studies based on the association between exosomal miRNAs and DKD.

The role of miRNAs carried by extracellular vesicles in type 2 diabetes and its complications

Diabetes poses severe global public health problems and places heavy burdens on the medical and economic systems of society. Type 2 diabetes (T2D) accounts for 90% of these cases. Diabetes also often accompanies serious complications that threaten multiple organs such as the brain, eyes, kidneys, and the cardiovascular system. MicroRNAs (miRNAs) carried by extracellular vesicles (EV-miRNAs) are considered to mediate cross-organ and cross-cellular communication and have a vital role in the pathophysiology of T2D. They also offer promising sources of diabetes-related biomarkers and serve as effective therapeutic targets. Here, we briefly reviewed studies of EV-miRNAs in T2D and related complications. Specially, we innovatively explore the targeting nature of miRNA action due to the target specificity of vesicle binding, aiding mechanism understanding as well as the detection and treatment of diseases.

Exosomes as biomarkers and therapy in type 2 diabetes mellitus and associated complications

Type 2 diabetes mellitus (T2DM) is one of the most prevalent metabolic disorders worldwide. However, T2DM still remains underdiagnosed and undertreated resulting in poor quality of life and increased morbidity and mortality. Given this ongoing burden, researchers have attempted to locate new therapeutic targets as well as methodologies to identify the disease and its associated complications at an earlier stage. Several studies over the last few decades have identified exosomes, small extracellular vesicles that are released by cells, as pivotal contributors to the pathogenesis of T2DM and its complications. These discoveries suggest the possibility of novel detection and treatment methods. This review provides a comprehensive presentation of exosomes that hold potential as novel biomarkers and therapeutic targets. Additional focus is given to characterizing the role of exosomes in T2DM complications, including diabetic angiopathy, diabetic cardiomyopathy, diabetic nephropathy, diabetic peripheral neuropathy, diabetic retinopathy, and diabetic wound healing. This study reveals that the utilization of exosomes as diagnostic markers and therapies is a realistic possibility for both T2DM and its complications. However, the majority of the current research is limited to animal models, warranting further investigation of exosomes in clinical trials. This review represents the most extensive and up-to-date exploration of exosomes in relation to T2DM and its complications.

Exosomes: Potential Next-Generation Nanocarriers for the Therapy of Inflammatory Diseases

Inflammatory diseases are common pathological processes caused by various acute and chronic factors, and some of them are autoimmune diseases. Exosomes are fundamental extracellular vesicles secreted by almost all cells, which contain a series of constituents, i.e., cytoskeletal and cytosolic proteins (actin, tubulin, and histones), nucleic acids (mRNA, miRNA, and DNA), lipids (diacylglycerophosphates, cholesterol, sphingomyelin, and ceramide), and other bioactive components (cytokines, signal transduction proteins, enzymes, antigen presentation and membrane transport/fusion molecules, and adhesion molecules). This review will be a synopsis of the knowledge on the contribution of exosomes from different cell sources as possible therapeutic agents against inflammation, focusing on several inflammatory diseases, neurological diseases, rheumatoid arthritis and osteoarthritis, intestinal bowel disease, asthma, and liver and kidney injuries. Current knowledge indicates that the role of exosomes in the therapy of inflammation and in inflammatory diseases could be distinctive. The main limitations to their clinical translation are still production, isolation, and storage. Additionally, there is an urgent need to personalize the treatments in terms of the selection of exosomes; their dosages and routes of administration; and a deeper knowledge about their biodistribution, type and incidence of adverse events, and long-term effects of exosomes. In conclusion, exosomes can be a very promising next-generation therapeutic option, superior to synthetic nanocarriers and cell therapy, and can represent a new strategy of effective, safe, versatile, and selective delivery systems in the future.

Exosomes: A Promising Strategy for Repair, Regeneration and Treatment of Skin Disorders

The skin is the organ that serves as the outermost layer of protection against injury, pathogens, and homeostasis with external factors; in turn, it can be damaged by factors such as burns, trauma, exposure to ultraviolet light (UV), infrared radiation (IR), activating signaling pathways such as Toll-like receptors (TLR) and Nuclear factor erythroid 2-related factor 2 (NRF2), among others, causing a need to subsequently repair and regenerate the skin. However, pathologies such as diabetes lengthen the inflammatory stage, complicating the healing process and, in some cases, completely inhibiting it, generating susceptibility to infections. Exosomes are nano-sized extracellular vesicles that can be isolated and purified from different sources such as blood, urine, breast milk, saliva, urine, umbilical cord bile cells, and mesenchymal stem cells. They have bioactive compounds that, thanks to their paracrine activity, have proven to be effective as anti-inflammatory agents, inducers of macrophage polarization and accelerators of skin repair and regeneration, reducing the possible complications relating to poor wound repair, and prolonged inflammation. This review provides information on the use of exosomes as a promising therapy against damage from UV light, infrared radiation, burns, and skin disorders.

Lack of expression of miR-29a/b1 impairs bladder function in male mice

Lower urinary tract symptoms (LUTS) refer to various urological diseases, and incomplete bladder emptying is common among affected patients. The etiology of LUTS is largely unknown, and investigations of LUTS suggest that bladder fibrosis contributes to pathogenesis of LUTS. MicroRNAs (miRNAs) are short (∼22 nucleotides), non-coding RNAs that repress target gene expression by a combination of mRNA degradation and translation inhibition. The miR-29 family is best known for its anti-fibrotic role in various organs. miR-29 was decreased in bladders of patients with outlet obstruction and a rat model of bladder outlet obstruction, suggesting that miR-29 may contribute to impaired bladder function subsequent to tissue fibrosis. We characterized bladder function in male mice lacking expression of Mir29a and Mir29b-1 (miR-29a/b1). Lack of miR-29a/b1 resulted in severe urinary retention, increased voiding duration and reduced flow rate, and these mice failed to void or voided irregularly during anesthetized cytometry. Collagens and elastin were increased in bladders of mice lacking miR-29a/b1. These findings reveal an important role for miR-29 in bladder homeostasis and suggest the therapeutic potential of miR-29 to improve symptoms in patients with LUTS.

Stem cell-derived exosomal MicroRNAs: Potential therapies in diabetic kidney disease

The diabetic kidney disease (DKD) is chronic kidney disease caused by diabetes and one of the most common comorbidities. It is often more difficult to treat end-stage renal disease once it develops because of its complex metabolic disorders, so early prevention and treatment are important. However, currently available DKD therapies are not ideal, and novel therapeutic strategies are urgently needed. The potential of stem cell therapies partly depends on their ability to secrete exosomes. More and more studies have shown that stem cell-derived exosomes take part in the DKD pathophysiological process, which may offer an effective therapy for DKD treatment. Herein, we mainly review potential therapies of stem cell-derived exosomes mainly stem cell-derived exosomal microRNAs in DKD, including their protective effects on mesangial cells, podocytes and renal tubular epithelial cells. Using this secretome as possible therapeutic drugs without potential carcinogenicity should be the focus of further research.

Roles of extracellular vesicles in ageing-related chronic kidney disease: demon or angel

Ageing is a universal and unavoidable phenomenon that significantly increases the risk of developing chronic kidney disease (CKD). It has been reported that ageing is associated with functional disruption and structural damage to the kidneys. Extracellular vesicles (EVs), which are nanoscale membranous vesicles containing lipids, proteins, and nucleic acids, are secreted by cells into the extracellular spaces. They have diverse functions such as repairing and regenerating different forms of ageing-related CKD and playing a crucial role in intercellular communication. This paper reviews the etiology of ageing in CKD, with particular attention paid to the roles of EVs as carriers of ageing signals and anti-ageing therapeutic strategies in CKD. In this regard, the double-edged role of EVs in ageing-related CKD is examined, along with the potential for their application in clinical settings.

Expression Patterns of MiR-125a and MiR-223 and Their Association with Diabetes Mellitus and Survival in Patients with Non-ST-Segment Elevation Acute Coronary Syndrome

Background: MicroRNAs (miRNA, miR) are small, non-coding RNAs which have become increasingly relevant as diagnostic and prognostic biomarkers. The objective of this study was the investigation of blood-derived miRNAs and their link to long-term all-cause mortality in patients who suffered from non-ST-segment elevation acute coronary syndrome (NSTE-ACS). Methods: This study was an observational prospective study, which included 109 patients with NSTE-ACS. Analysis of the expression of miR-125a and miR-223 was conducted by polymerase chain reaction (PCR). The follow-up period comprised a median of 7.5 years. Long-term all-cause mortality was considered as the primary endpoint. Adjusted Cox-regression analysis was performed for prediction of events. Results: Increased expression of miR-223 (>7.1) at the time point of the event was related to improved long-term all-cause survival (adjusted (adj.) hazard ratio (HR) = 0.09, 95% confidence interval (95%CI): 0.01-0.75; p = 0.026). The receiver operating characteristic (ROC) analysis provided sufficient c-statistics (area under the curve (AUC) = 0.73, 95%CI: 0.58-0.86; p = 0.034; negative predictive value of 98%) for miR-223 to predict long-term all-cause survival. The Kaplan-Meier time to event analysis showed a separation of the survival curves between the groups at an early stage (log rank p = 0.015). Higher plasma miR-125a levels were found in patients with diabetes mellitus vs. in those without (p = 0.010). Furthermore, increased miR-125a expression was associated with an elevated HbA1c concentration. Conclusions: In this hypothesis-generating study, higher values of miR-223 were related to improved long-term survival in patients after NSTE-ACS. Larger studies are required in order to evaluate whether miR-223 can be used as a suitable predictor for long-term all-cause mortality.

An update on renal fibrosis: from mechanisms to therapeutic strategies with a focus on extracellular vesicles

The increasing prevalence of chronic kidney disease (CKD) is a major global public health concern. Despite the complicated pathogenesis of CKD, renal fibrosis represents the most common pathological condition, comprised of progressive accumulation of extracellular matrix in the diseased kidney. Over the last several decades, tremendous progress in understanding the mechanism of renal fibrosis has been achieved, and corresponding potential therapeutic strategies targeting fibrosis-related signaling pathways are emerging. Importantly, extracellular vesicles (EVs) contribute significantly to renal inflammation and fibrosis by mediating cellular communication. Increasing evidence suggests the potential of EV-based therapy in renal inflammation and fibrosis, which may represent a future direction for CKD therapy.

Research Progress on Mesenchymal Stem Cells for the Treatment of Diabetes and Its Complications

Diabetes mellitus (DM) is a chronic disease that threatens human health. Although many drugs are available to treat DM, various complications caused by DM are unavoidable. As an emerging treatment for DM, mesenchymal stem cells (MSCs) have shown many advantages and are gradually gaining public attention. This review summarizes the clinical studies on the use of MSCs to treat DM and the potential mechanisms of complications such as pancreatic dysfunction, cardiovascular lesions, renal lesions, neurological lesions, and trauma repair. This review focuses on the research progress on MSC-mediated secretion of cytokines, improvements in the microenvironment, repair of tissue morphology, and related signaling pathways. At present, the sample sizes in clinical studies of MSCs in treating DM are small, and there is a lack of standardized quality control systems in the preparation, transportation, and infusion methods, so we need to conduct more in-depth studies. In conclusion, MSCs have shown superior potential for use in the treatment of DM and its complications and will hopefully become a novel therapeutic approach in the future.

miRNAs as cornerstones in diabetic microvascular complications

Diabetes mellitus is usually accompanied by nephropathy, retinopathy, and neuropathy as microvascular complications. MicroRNAs (miRNAs) can affect the kidney, retina, and peripheral neurons through their implication in pathways involved in angiogenesis, inflammation, apoptosis, as well as fibrosis within these tissues and hence, play a crucial role in the pathogenesis of microvascular complications. In this review, the updated knowledge of the role of miRNAs in the pathogenesis of diabetic microvascular complications was summarized. PubMed Central was searched extensively to retrieve data from a wide range of reputable biomedical reports/articles published after the year 2000 to systematically collect and present a review of the key molecular pathways mediating the hyperglycemia-induced adverse effects on vascular tissues, particularly in persons with T2DM. In the present review, miR-126, miR-29b, and miR-125a are implicated in diabetes-induced microvascular complications, while miR-146a is found to be connected to all these complications. Also, vascular endothelial growth factors are noted to be the most impacted targets by miRNAs in all diabetic microvascular problems.

Mesenchymal Stem Cell-Derived Extracellular Vesicles: A Potential Therapy for Diabetes Mellitus and Diabetic Complications

As a novel cell-free strategy, mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) inherit the therapeutic potential of donor cells, and are widely used for the treatment of many diseases. Increasing studies have shown that MSC-EVs transfer various bioactive molecules to create a beneficial microenvironment, thus exerting protective roles in diabetic mellitus (DM) and diabetic complications. To overcome the limitations of natural MSC-EVs such as heterogeneity and insufficient function, several modification methods have been established for constructing engineered MSC-EVs with elevated repairing efficiency. In this review, the PubMed library was searched from inception to August 2022, using a combination of Medical Subject Headings (MeSH) and keywords related to MSC-EVs, DM, and diabetic complications. We provide an overview of the major characteristics of MSC-EVs and summarize the recent advances of MSC-EV-based therapy for hyperglycemia-induced tissue damage with an emphasis on MSC-EV-mediated delivery of functional components. Moreover, the potential applications of engineered MSC-EVs in DM-related diseases therapy are discussed by presenting examples, and the opportunities and challenges for the clinical translation of MSC-EVs, especially engineered MSC-EVs, are evaluated.

Role of exosomes and exosomal microRNA in muscle–Kidney crosstalk in chronic kidney disease

Chronic kidney disease (CKD) is a progressive damage of kidneys that can no longer serve the blood-filtering function, and is a life-threatening condition. Skeletal muscle wasting is a common complication of CKD. Yet the relationship between kidney and skeletal muscle in CKD remains unclear. Exosomes, a type of small membrane-bound vesicles released from cells to the extracellular environment, have increasingly received attention due to their potential as mediators of crosstalk between kidneys and different organs, including skeletal muscle. This mini-review summarizes the recent findings that point to the role of exosomes in the cross-talk between kidney and skeletal muscle in CKD. Understanding of the contents and the mechanism of exosome release may prone exosomes be the potential therapeutic targets for CKD.

Mesenchymal Stem Cell-Derived Small Extracellular Vesicles: A Novel Approach for Kidney Disease Treatment

Globally, kidney disease has become a serious health challenge, with approximately 10% of adults suffering with the disease, and increasing incidence and mortality rates every year. Small extracellular vesicles (sEVs) are 30 nm-100 nm sized nanovesicles released by cells into the extracellular matrix (ECM), which serve as mediators of intercellular communication. Depending on the cell origin, sEVs have different roles which depend on internal cargoes including, nucleic acids, proteins, and lipids. Mesenchymal stem cell (MSCs) exert anti-inflammatory, anti-aging, and wound healing functions mainly via sEVs in a stable and safe manner. MSC-derived sEVs (MSC-sEVs) exert roles in several kidney diseases by transporting renoprotective cargoes to reduce oxidative stress, inhibit renal cell apoptosis, suppress inflammation, and mediate anti-fibrosis mechanisms. Additionally, because MSC-sEVs efficiently target damaged kidneys, they have the potential to become the next generation cell-free therapies for kidney disease. Herein, we review recent research data on how MSC-sEVs could be used to treat kidney disease.

Tailored Extracellular Vesicles: Novel Tool for Tissue Regeneration

Extracellular vesicles (EVs) play an essential part in multiple pathophysiological processes including tissue injury and regeneration because of their inherent characteristics of small size, low immunogenicity and toxicity, and capability of carrying a variety of bioactive molecules and mediating intercellular communication. Nevertheless, accumulating studies have shown that the application of EVs faces many challenges such as insufficient therapeutic efficacy, a lack of targeting capability, low yield, and rapid clearance from the body. It is known that EVs can be engineered, modified, and designed to encapsulate therapeutic cargos like proteins, peptides, nucleic acids, and drugs to improve their therapeutic efficacy. Targeted peptides, antibodies, aptamers, magnetic nanoparticles, and proteins are introduced to modify various cell-derived EVs for increasing targeting ability. In addition, extracellular vesicle mimetics (EMs) and self-assembly EV-mimicking nanocomplex are applied to improve production and simplify EV purification process. The combination of EVs with biomaterials like hydrogel, and scaffolds dressing endows EVs with long-term therapeutic efficacy and synergistically enhanced regenerative outcome. Thus, we will summarize recent developments of EV modification strategies for more extraordinary regenerative effect in various tissue injury repair. Subsequently, opportunities and challenges of promoting the clinical application of engineered EVs will be discussed.

An overview of the efficacy and signaling pathways activated by stem cell-derived extracellular vesicles in diabetic kidney disease

Diabetic kidney disease (DKD) is one of complications of diabetes mellitus with severe microvascular lesion and the most common cause of end-stage chronic kidney disease (ESRD). Controlling serum glucose remains the primary approach to preventing and slowing the progression of DKD. Despite considerable efforts to control diabetes, people with diabetes develop not only DKD but also ESRD. The pathogenesis of DKD is very complex, and current studies indicate that mesenchymal stromal cells (MSCs) regulate complex disease processes by promoting pro-regenerative mechanisms and inhibiting multiple pathogenic pathways. Extracellular vesicles (EVs) are products of MSCs. Current data indicate that MSC-EVs-based interventions not only protect renal cells, including renal tubular epithelial cells, podocytes and mesangial cells, but also improve renal function and reduce damage in diabetic animals. As an increasing number of clinical studies have confirmed, MSC-EVs may be an effective way to treat DKD. This review explores the potential efficacy and signaling pathways of MSC-EVs in the treatment of DKD.

Mesenchymal stem cells derived extracellular vesicles: A promising nanomedicine for drug delivery system

An ideal drug delivery system should selectively deliver incorporated therapeutics to the target site, escape from immune cells recognition and degradation, and act controlled release of incorporated therapeutics in the site targeted. Extracellular vesicles (EVs) have gained great attention for their potential application as a drug delivery system in nanomedicine. EVs such as exosomes are membrane-bound vesicles that contribute to intracellular communication by transferring various biomolecules including RNAs, proteins, and lipids. EVs derived from mesenchymal stem cells (MSCs-EVs) have several advantages such as low immunogenicity, high biocompatibility, and stability against conventional synthetic carriers, opening new avenues for delivering theaputic agents to target cells. To obtain modified MSCs-EVs, several loading methods are used to incorporate different therapeutic agents including proteins, RNAs, and chemotherapeutic drugs into MSCs-EVs. In addition, modification of MSCs-EVs surface may improve their potential in targeted therapies. Modified MSCs-EVs have been shown to improve many diseases including, cancer, cardiovascular diseases, and diabetes mellitus. While land greatly potential, the application of MSCs-EVs as a drug-delivery system has been hampered by several challenges. Clinical translation of modified-EVs needs further scrutiny. In this review, we discuss the biogenesis and production of EVs along with the loading and modification methods of MSCs-EVs. We also describe numerous MSCs-EVs based delivery studies with a focus on advantages and challenges when using them as a drug delivery system.

Mesenchymal Stem Cell-Derived Exosomes: Toward Cell-Free Therapeutic Strategies in Chronic Kidney Disease

Chronic kidney disease (CKD) is rising in global prevalence and has become a worldwide public health problem, with adverse outcomes of kidney failure, cardiovascular disease, and premature death. However, current treatments are limited to slowing rather than reversing disease progression or restoring functional nephrons. Hence, innovative strategies aimed at kidney tissue recovery hold promise for CKD therapy. Mesenchymal stem cells (MSCs) are commonly used for regenerative therapy due to their potential for proliferation, differentiation, and immunomodulation. Accumulating evidence suggests that the therapeutic effects of MSCs are largely mediated by paracrine secretion of extracellular vesicles (EVs), predominantly exosomes. MSC-derived exosomes (MSC-Exos) replicate the functions of their originator MSCs via delivery of various genetic and protein cargos to target cells. More recently, MSC-Exos have also been utilized as natural carriers for targeted drug delivery. Therapeutics can be effectively incorporated into exosomes and then delivered to diseased tissue. Thus, MSC-Exos have emerged as a promising cell-free therapy in CKD. In this paper, we describe the characteristics of MSC-Exos and summarize their therapeutic efficacy in preclinical animal models of CKD. We also discuss the potential challenges and strategies in the use of MSC-Exos-based therapies for CKD in the future.

Mesenchymal Stem Cell-Derived Extracellular Vesicles as Non-Coding RNA Therapeutic Vehicles in Autoimmune Diseases

Autoimmune diseases (ADs) are characterized by the activation of the immune system against self-antigens. More common in women than in men and with an early onset, their incidence is increasing worldwide, and this, combined with their chronic nature, is contributing to an enlarged medical and economic burden. Conventional immunosuppressive agents are designed to alleviate symptoms but do not constitute an effective therapy, highlighting a need to develop new alternatives. In this regard, mesenchymal stem cells (MSCs) have demonstrated powerful immunosuppressive and regenerative effects. MSC-derived extracellular vesicles (MSC-EVs) have shown some advantages, such as less immunogenicity, and are proposed as novel therapies for ADs. In this review, we summarize current perspectives on therapeutic options for ADs based on MSCs and MSC-EVs, focusing particularly on their mechanism of action exerted through their non-coding RNA (ncRNA) cargo. A complete state-of-the-art review was performed, centralized on some of the most severe ADs (rheumatoid arthritis, autoimmune type 1 diabetes mellitus, and systemic lupus erythematosus), giving evidence that a promising field is evolving to overcome the current knowledge and provide new therapeutic possibilities centered on MSC-EVs and their role as ncRNA delivery vehicles for AD gene therapy.

Exosomal circTAOK1 contributes to diabetic kidney disease progression through regulating SMAD3 expression by sponging miR-520h

BACKGROUND

Diabetic nephropathy (DN) is a frequent diabetes complication with complex pathogenesis. Circular RNA (circRNA) circTAOK1 (also named circ_0003928) has been reported to be upregulated in high glucose (HG)-treated human umbilical vein endothelial cells. Also, exosomal circRNAs can exert significant roles in the pathology of various diseases. This study is designed to explore the role and mechanism of exosomal circTAOK1 on the glomerular mesangial cell (GMC) injury in DN.

METHODS

Exosomes were detected by a transmission electron microscope. The protein levels of CD9, CD63, proliferating cell nuclear antigen (PCNA), cyclinD1, α-SMA, fibronectin, E-cadherin, N-cadherin, and SMAD family member 3 (SMAD3) were examined by western blot assay. circTAOK1, microRNA-520h (miR-520h), and SMAD3 levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell proliferation and cell cycle progression were detected by cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), and flow cytometry assays. The binding relationship between miR-520h and circTAOK1 or SMAD3 was predicted by Starbase and then verified by a dual-luciferase reporter and RNA immunoprecipitation (RIP), RNA pull-down assays.

RESULTS

CircTAOK1 expression was upregulated in the exosomes isolated from HG-treated glomerular epithelial cells (GEC). Moreover, GEC-circTAOK1-Exo could promote proliferation, fibrosis, and epithelial-mesenchymal transition (EMT) of glomerular mesangial cells (GMCs). Mechanically, circTAOK1 could regulate SMAD3 expression by sponging miR-520h, GEO-si-circTAOK1 Exo-induced miR-520h and repressed SMAD3 expression in GMC.

CONCLUSION

GEC-circTAOK1-Exo could boost proliferation, fibrosis, and EMT of GMC through targeting the miR-520h/SMAD3 axis, providing new insights into the pathogenesis of DN.

Stem cell-derived and circulating exosomal microRNAs as new potential tools for diabetic nephropathy management

BACKGROUND

Despite major advances in the treatment of diabetic nephropathy (DN) in recent years, it remains the most common cause of end-stage renal disease. An early diagnosis and therapy may slow down the DN progression. Numerous potential biomarkers are currently being researched. Circulating levels of the kidney-released exosomes and biological molecules, which reflect the DN pathology including glomerular and tubular dysfunction as well as mesangial expansion and fibrosis, have shown the potential for predicting the occurrence and progression of DN. Moreover, many experimental therapies are currently being investigated, including stem cell therapy and medications targeting inflammatory, oxidant, or pro-fibrotic pathways activated during the DN progression. The therapeutic potential of stem cells is partly depending on their secretory capacity, particularly exosomal microRNAs (Exo-miRs). In recent years, a growing line of research has shown the participation of Exo-miRs in the pathophysiological processes of DN, which may provide effective therapeutic and biomarker tools for DN treatment.

METHODS

A systematic literature search was performed in MEDLINE, Scopus, and Google Scholar to collect published findings regarding therapeutic stem cell-derived Exo-miRs for DN treatment as well as circulating Exo-miRs as potential DN-associated biomarkers.

FINDINGS

Glomerular mesangial cells and podocytes are the most important culprits in the pathogenesis of DN and, thus, can be considered valuable therapeutic targets. Preclinical investigations have shown that stem cell-derived exosomes can exert beneficial effects in DN by transferring renoprotective miRs to the injured mesangial cells and podocytes. Of note, renoprotective Exo-miR-125a secreted by adipose-derived mesenchymal stem cells can improve the injured mesangial cells, while renoprotective Exo-miRs secreted by adipose-derived stem cells (Exo-miR-486 and Exo-miR-215-5p), human urine-derived stem cells (Exo-miR-16-5p), and bone marrow-derived mesenchymal stem cells (Exo-miR-let-7a) can improve the injured podocytes. On the other hand, clinical investigations have indicated that circulating Exo-miRs isolated from urine or serum hold great potential as promising biomarkers in DN.

The roles of mesenchymal stem cell-derived exosomes in diabetes mellitus and its related complications

Diabetes mellitus is a type of metabolic disease characterized by hyperglycemia, primarily caused by defects in insulin secretion, insulin action, or both. Long-term chronic hyperglycemia can lead to diabetes-related complications, causing damage, dysfunction, and failure of different organs. However, traditional insulin and oral drug therapy can only treat the symptoms but not delay the progressive failure of pancreatic beta cells or prevent the emergence of diabetic complications. Mesenchymal stem cells have received extensive attention due to their strong immunoregulatory functions and regeneration effects. Mesenchymal stem cell-derived exosomes (MSC-Exos) have been proposed as a novel treatment for diabetic patients as they have demonstrated superior efficiency to mesenchymal stem cells. This review summarizes the therapeutic effects, mechanisms, challenges, and future prospects of MSC-Exos in treating diabetes mellitus and its related complications. This review supports the potential use of MSC-Exos in future regenerative medicine to overcome the current difficulties in clinical treatment, particularly in treating diabetes.

Mesenchymal stem cells-derived exosomes for drug delivery

Exosomes are extracellular vesicles secreted by various cells, mainly composed of lipid bilayers without organelles. In recent years, an increasing number of researchers have focused on the use of exosomes for drug delivery. Targeted drug delivery in the body is a promising method for treating many refractory diseases such as tumors and Alzheimer's disease (AD). Finding a suitable drug delivery carrier in the body has become a popular research today. In various drug delivery studies, the exosomes secreted by mesenchymal stem cells (MSC-EXOs) have been broadly researched due to their immune properties, tumor-homing properties, and elastic properties. While MSC-EXOs have apparent advantages, some unresolved problems also exist. This article reviews the studies on MSC-EXOs for drug delivery, summarizes the characteristics of MSC-EXOs, and introduces the primary production and purification methods and drug loading methods to provide solutions for existing problems and suggestions for future studies.

High Therapeutic and Esthetic Properties of Extracellular Vesicles Produced from the Stem Cells and Their Spheroids Cultured from Ocular Surgery-Derived Waste Orbicularis Oculi Muscle Tissues

Extracellular vesicles (EVs) are paracrine factors that mediate stem cell therapeutics. We aimed at evaluating the possible therapeutic and esthetic applications of EVs prepared from the waste human facial tissue-derived orbicularis oculi muscle stem cells (OOM-SCs). OOM-SCs were isolated from the ocular tissues (from elders and youngsters) after upper eyelid blepharoplasty or epiblepharon surgeries. EVs were prepared from the OOM-SCs (OOM-SC-EVs) and their three-dimensional spheroids. OOM-SCs showed a spindle-like morphology with trilineage differentiation capacity, positive expression of CD105, CD 90, and CD73, and negative expression of CD45 and CD34, and their stem cell properties were compared with other adult mesenchymal stem cells. OOM-SC-EVs showed a high inhibitory effect on melanin synthesis in B16F10 cells by blocking tyrosinase activity. OOM-SC-EVs treatment led to a significant attenuation of senescence-associated changes, a decrease in reactive oxygen species generation, and an upregulation of antioxidant genes. We demonstrated the regeneration activity of OOM-SC-EVs in in vitro wound healing of normal human dermal fibroblasts and upregulation of anti-wrinkle-related genes and confirmed the therapeutic potential of OOM-SC-EVs in the healing of the in vivo wound model. Our study provides promising therapeutic and esthetic applications of OOM-SC-EVs, which can be obtained from the ocular surgery-derived waste human facial tissues.