Bone marrow mesenchymal stem cells-induced exosomal microRNA-486-3p protects against diabetic retinopathy through TLR4/NF-κB axis repression

Profiling the Ocular Landscape of sEVs miRNAs: Mechanisms and Applications

In this review, we comprehensively discuss the application of sEVs miRNAs in ophthalmic diseases by examining their basic characteristics and clinical application potential. Initially, we provide an overview of sEVs, including their definition, source, and functions, while particularly highlighting the importance of miRNAs contained in sEVs and its prospects in the treatment of ocular diseases. Subsequently, the structure and composition of sEVs as well as the biological functions of their encapsulated miRNAs, which expands the current knowledge about their roles in ophthalmic physiology and pathology. In addition, the functions of sEVs miRNAs in the growth of ocular tissues, ocular tissue homeostasis, and common eye diseases such as glaucoma, age-related macular degeneration, and diabetic retinopathy, are discussed. The application potential of sEVs miRNAs as diagnostic biomarkers and drug delivery systems for ophthalmic conditions and therapeutic value in diverse eye diseases are explored. Finally, the current challenges affecting research in this field are outlined to provide a basis that guide future utilization of sEVs miRNAs in ophthalmic disease research and clinical management of diverse ophthalmological conditions.

Facile fabrication of redox nanoparticles loaded with exosomal-miRNAs and resveratrol as glycation inhibitor in alleviating the progression and development of diabetic cataract

Diabetic cataract (DC) represents a highly prevalent ocular manifestation resulting from diabetes often culminating in vision impairment among individuals with diabetes. Regrettably, the armamentarium of pharmaceutical interventions capable of both delaying and thwarting the onset of DC remains conspicuously sparse. Based on contemporary investigations, the pathogenesis of DC is prominently influenced by oxidative harm to the crystalline lens and the nonenzymatic glycosylation of lens proteins. Consequently, we have developed self-regenerating cerium oxide nanoparticles (CeO2 NPs), enveloped with resveratrol (RSV) and exosomal-microRNA (miRNA) to alleviate the effects of DC in an in vitro model. Moreover, the inclusion of RSV within CeO2 NPs serves a dual purpose. It can act as an antioxidant, minimizing glycation, and induce oxidative stress by effectively neutralizing reactive oxygen species (ROS). Additionally, it serves as a glycation inhibitor effectively preventing the cross-linking. Consequently, it helps minimize the glucose level in hemoglobin and inhibits the formation of advanced glycation end products (AGEs). Likewise, the CeO2-exosomal-miRNA when treated alone found to slightly impede the viability of human lens epithelial cells (HLEC) and induce apoptosis by suppressing the expression of α-crystalline gene (CRYAA). Particularly, miRNAs target genes associated with oxidative stress pathways, protein glycation, and the generation of AGEs, hence preventing structural damage to lens proteins. Compared with CeO2, RSV-CeO2, and miRNA-RSV-CeO2, the presence of miRNA-RSV-CeO2 led to a significant decrease in hemoglobin glycation. Remarkably, miRNA-RSV-CeO2 NPs attenuate the formation of malondialdehyde (MDA) and conjugated dienes (CD) with a relative value of 14.63 and 11.37 nmol/mg. As per the report, this method presents a promising opportunity to implement the proposed material combination for attenuating diabetic cataracts.

Circulating miR-486-3p as a potential biomarker for the diagnosis of gestational diabetes mellitus and the prediction of adverse pregnancy outcomes

OBJECTIVE

Gestational diabetes mellitus (GDM) seriously endangers the health of pregnant women and their offspring. Early prediction and diagnosis allow timely treatment of GDM, preventing adverse pregnancy outcomes and related diseases. This research aims to explore the predictive significance of miR-486-3p expression levels in diagnosing GDM in early pregnancy.

METHODS

A retrospective study was conducted by enrolling 103 subjects with GDM and 98 healthy subjects. qRT-PCR was used to analyze the expression level of miR-486-3p. The chi-square test and t-test were used to evaluate the differences in miR-486-3p expression levels between the GDM and control groups. The predictive value of miR-486-3p in early diagnosis of GDM was analyzed by receiver operating characteristic (ROC). Potential indicators that may lead to adverse pregnancy outcomes in patients with GDM were predicted by multivariate logistic regression analysis.

RESULTS

Downregulation of miR-486-3p expression level was observed in the GDM group compared with healthy individuals. The predictive value of miR-486-3p for early diagnosis of GDM was indicated by the ROC curve. The expression level of miR-486-3p in the GDM group was negatively correlated with glycated hemoglobin (HbA1c), fasting blood glucose (FBG), homeostasis model-insulin resistance index (HOMA-IR), and leptin (LEP). Multivariate logistic regression analysis suggested that miR-486-3p, HbA1c, HOMA-IR, and FBG could be regarded as adverse pregnancy outcome risk factors in GDM subjects.

CONCLUSION

miR-486-3p showed a clinical predictive value for GDM in early pregnancy. miR-486-3p, HbA1c, HOMA-IR, and FBG indicators can be considered adverse pregnancy outcome risk factors in GDM patients.

TSH-stimulated hepatocyte exosomes modulate liver-adipose triglyceride accumulation via the TGF-β1/ATGL axis in mice

Subclinical hypothyroidism (SCH) contributes to obesity, with the liver acting as a crucial metabolic regulator. Thyroid-stimulating hormone (TSH) affects systemic lipid balance, potentially linking SCH to obesity. While the direct impact of TSH on hepatic lipid metabolism has been extensively documented, its role in modulating lipid dynamics in peripheral organs through liver-mediated pathways remains insufficiently understood. This study identifies TSH-stimulated hepatocyte-derived exosomes (exosomesTSH) as key mediators in liver-adipose communication, promoting triglyceride accumulation in adipocytes via the transforming growth factor-beta 1 (TGF-β1)/adipose triglyceride lipase (ATGL) axis. ExosomesTSH enhance lipid storage in adipocytes, significantly increasing triglyceride content and lipid droplet formation while reducing lipolysis, effects that are dependent on TSH receptor (TSHR) activation in hepatocytes. In vivo, exosomesTSH induce weight gain and adipose tissue expansion, impairing glucose metabolism in both chow- and high-fat diet-fed mice. Mechanistically, exosomesTSH upregulate TGF-β1 and downregulate ATGL in adipocytes, establishing the TGF-β1/ATGL pathway as essential for exosome-mediated lipid accumulation. Further, miR-139-5p is identified as a modulator of TGF-β1 expression within this pathway, with overexpression of miR-139-5p alleviating exosomesTSH-induced lipid accumulation in adipocytes. This study elucidates a novel miR-139-5p-dependent mechanism through which TSH modulates lipid metabolism via liver-derived exosomes, highlighting the pivotal role of miR-139-5p in linking SCH to adipose lipid accumulation through the TGF-β1/ATGL signaling axis.

Mesenchymal stem cells and mesenchymal stem cell-derived exosomes: a promising strategy for treating retinal degenerative diseases

Mesenchymal stem cells (MSCs) have emerged as a promising therapeutic strategy in regenerative medicine, demonstrating significant potential for clinical applications. Evidence suggests that MSCs not only exhibit multipotent differentiation potential but also exert critical therapeutic effects in retinal degenerative diseases via robust paracrine mechanisms. MSCs protect retinal cells from degenerative damage by modulating inflammation, inhibiting apoptosis, alleviating oxidative stress, and suppressing cell death pathways. Furthermore, MSCs contribute to retinal structural and functional stability by facilitating vascular remodeling and donating mitochondria to retinal cells. Of particular interest, MSC-derived exosomes have gained widespread attention as a compelling cell-free therapy. Owing to their potent anti-inflammatory, anti-apoptotic, and vascular-stabilizing properties, exosomes show significant promise for the treatment of retinal degenerative diseases.

The role of metal nanocarriers, liposomes and chitosan-based nanoparticles in diabetic retinopathy treatment: A review study

Diabetic Retinopathy (DR) is a significant and progressive eye complication associated with diabetes mellitus, leading to potential vision loss. The pathophysiology of DR involves complex neurovascular changes due to prolonged hyperglycemia, resulting in microangiopathy and neurodegeneration. Current treatment modalities come with limitations such as low bioavailability of therapeutic agents, risk of side effects, and surgical complications. Consequently, the prevention and management of DR, particularly in its advanced stages, present ongoing challenges. This review investigates recent advancements in nanotechnology as a novel approach to enhance the treatment of DR. A comprehensive literature review of recent studies focusing on nanocarriers for drug delivery in DR treatment and an analysis of their efficacy compared to traditional methods was conducted for this study. The findings indicate that nanotechnology can significantly enhance the bioavailability of therapeutic agents while minimizing systemic exposure and associated side effects. The novelty of this study lies in its focus on the intersection of nanotechnology and ophthalmology, exploring innovative solutions that extend beyond existing literature on DR treatments. By highlighting recent advancements in this field, the study paves the way for future research aimed at developing more effective therapeutic strategies for managing DR.

Exosome's Implications in Age-Related Macular Degeneration

PURPOSE

This study aims to conduct a mini review of published literature concerning the role of exosomes in the field of ophthalmology, with a specific focus on Age-Related Macular Degeneration (AMD).

METHODS

In this study, a comprehensive search was conducted using PubMed and Google Scholar to identify relevant publications. Additionally, trials submitted to clinicaltrials.gov were reviewed to identify further relevant articles. The selected studies specifically focused on the ocular implications of exosomes in Age-Related Macular Degeneration.

RESULTS

Exosomes, small extracellular vesicles measuring less than 200 nm, play a crucial role in cell signaling and are involved in various physiological and pathological processes. Recent research has focused on utilizing exosomes for disease detection and treatment. Studies have investigated the ocular implications of exosomes, particularly in AMD. Exosomes found in aqueous fluid and blood have been examined as potential markers for AMD and as indicators of treatment response. Additionally, research in animal models has indicated the potential of exosomes in preventing AMD, as well as their promise for targeted and efficient drug delivery. This mini review primarily emphasizes the clinical aspects of publications related to AMD, rather than focusing solely on basic science.

CONCLUSIONS

Exosomes have a great potential for understanding Age-related Macular Degeneration and effective and targeted treatment for retinal diseases.

Potential Signal Pathways and Therapeutic Effects of Mesenchymal Stem Cell on Oxidative Stress in Diseases

Oxidative stress is a biological stress response produced by the destruction of redox equilibrium in aerobic metabolism in organisms, which is closely related to the occurrence of many diseases. Mesenchymal stem cells (MSCs) have been found to improve oxidative stress injury in a variety of diseases, including lung injury, liver diseases, atherosclerotic diseases, diabetes and its complications, ischemia-reperfusion injury, inflammatory bowel disease. The antioxidant stress capacity of MSCs may be a breakthrough in the treatment of these diseases. This review found that MSCs have the ability to resist oxidative stress, which may be achieved through MSCs involvement in mediating the Nrf2, MAPK, NF-κB, AMPK, PI3K/AKT and Wnt4/β-catenin signaling pathways.

Extracellular vesicles as emerging players in glaucoma: Mechanisms, biomarkers, and therapeutic targets

In recent years, extracellular vesicles (EVs) have attracted significant scientific interest due to their widespread distribution, their potential as disease biomarkers, and their promising applications in therapy. Encapsulated by lipid bilayers these nanovesicles include small extracellular vesicles (sEV) (30-150 nm), microvesicles (100-1000 nm), and apoptotic bodies (100-5000 nm) and are essential for cellular communication, immune responses, biomolecular transport, and physiological regulation. As they reflect the condition and functionality of their originating cells, EVs play critical roles in numerous physiological processes and diseases. Therefore, EVs offer valuable opportunities for uncovering disease mechanisms, enhancing drug delivery systems, and identifying novel biomarkers. In the context of glaucoma, a leading cause of irreversible blindness, the specific roles of EVs are still largely unexplored. This review examines the emerging role of EVs in the pathogenesis of glaucoma, with a focus on their potential as diagnostic biomarkers and therapeutic agents. Through a thorough analysis of current literature, we summarize key advancements in EV research and identify areas where further investigation is needed to fully understand their function in glaucoma.

Stem Cell-Derived Exosomes: Natural Intercellular Messengers with Versatile Mechanisms for the Treatment of Diabetic Retinopathy

Diabetic retinopathy is one of the complications of diabetes mellitus that occurs in the early stages. It is a disease that has a serious impact, and may lead to blindness when the disease progresses to advanced stages. Currently, treatments for diabetic retinopathy are mainly limited to its advanced stages of the disease, being restricted to a single therapeutic mechanism. Stem cells hold the promise of regenerative therapy and have the potential to comprehensively improve diabetic retinopathy. However, direct stem cell therapy carries some risk of carcinogenesis. Exosomes secreted by stem cells have shown a similar overall improvement in disease as stem cells. Exosomes can carry a number of biologically active materials from donor cells to recipient cells or distant organs, regulating intercellular signaling. Exosomes have shown remarkable efficacy in alleviating oxidative stress, inhibiting inflammatory responses, suppressing angiogenesis, reducing apoptosis and protecting neural tissues. Currently, the experimental literature using stem cell exosomes in the treatment of diabetic retinopathy tends to converge on the above experimental results. With this in mind, we have chosen to explore exosomes in depth from a subtle molecular perspective. We will elaborate on this perspective in this paper and propose to advocate exosome therapy as one promising approach for the treatment of diabetic retinopathy to ameliorate the lesions through multiple mechanisms.

Exosomes-mediated delivery of miR-486-3p alleviates neuroinflammation via SIRT2-mediated inhibition of mitophagy after subarachnoid hemorrhage

BACKGROUND

Neuroinflammation participates in the pathogenesis of subarachnoid haemorrhage (SAH); however, no effective treatments exist. MicroRNAs regulate several aspects of neuronal dysfunction. In a previous study, we found that exosomal miR-486-3p is involved in the pathophysiology of SAH. Targeted delivery of miR-486-3p without blood-brain barrier (BBB) restriction to alleviate SAH is a promising neuroinflammation approach.

METHODS

In this study, we modified exosomes (Exo) to form an RVG-miR-486-3p-Exo (Exo/miR) to achieve targeted delivery of miR-486-3p to the brain. Neurological scores, brain water content, BBB damage, flow cytometry and FJC staining were used to determine the effect of miR-486-3p on SAH. Western blot analysis, ELISA and RT-qPCR were used to measure relevant protein and mRNA levels. Immunofluorescence staining and laser confocal detection were used to measure the expression of mitochondria, lysosomes and autophagosomes, and transmission electron microscopy was used to observe the level of mitophagy in the brain tissue of mice after SAH.

RESULTS

Tail vein injection of Exo/miR improved targeting of miR-486-3p to the brains of SAH mice. The injection reduced levels of neuroinflammation-related factors by changing the phenotype switching of microglia, inhibiting the expression of sirtuin 2 (SIRT2) and enhancing mitophagy. miR-486-3p treatment alleviated neurobehavioral disorders, brain oedema, BBB damage and neurodegeneration. Further research found that the mechanism was achieved by regulating the acetylation level of peroxisome proliferator-activated receptor γ coactivator l alpha (PGC-1α) after SIRT2 enters the nucleus.

CONCLUSION

Exo/miR treatment attenuates neuroinflammation after SAH by inhibiting SIRT2 expression and stimulating mitophagy, suggesting potential clinical applications.

Research on the role of exosomes secreted by immortalized adipose-derived mesenchymal stem cells differentiated into pericytes in the repair of high glucose-induced retinal vascular endothelial cell damage

Diabetic retinopathy, a leading cause of vision impairment, is marked by microvascular complications in the retina, including pericyte loss, a key indicator of early-stage disease. This study explores the therapeutic potential of exosomes derived from immortalized adipose-mesenchymal stem cells differentiated into pericyte-like cells in restoring the function of mouse retinal microvascular endothelial cells damaged by high glucose conditions, thereby contributing to the understanding of early diabetic retinopathy intervention strategies. To induce immortalized adipose-mesenchymal stem cells differentiation into pericyte-like cells, the study employed pericyte growth supplement. And confirmed the success of cell differentiation through the detection of α-smooth muscle actin and neural/glial antigen 2 expression by Western blot and immunofluorescence. Exosomes were isolated from the culture supernatant of immortalized adipose-mesenchymal stem cells using ultracentrifugation and characterized through Western blot for exosomal markers (CD9, CD81, and TSG101), transmission electron microscopy, and nanoparticle tracking analysis. Their influence on mouse retinal microvascular endothelial cells under high glucose stress was assessed through various functional assays. Findings revealed that exosomes, especially those from pericyte-like immortalized adipose-mesenchymal stem cells, were efficiently internalized by retinal microvascular endothelial cells and effectively counteracted high glucose-induced apoptosis. These exosomes also mitigated the rise in reactive oxygen species levels and suppressed the migratory and angiogenic properties of retinal microvascular endothelial cells, as demonstrated by Transwell and tube formation assays, respectively. Furthermore, they preserved endothelial barrier function, reducing hyperglycemia-induced permeability. At the molecular level, qRT-PCR analysis showed that exosome treatment modulated the expression of critical genes involved in angiogenesis (VEGF-A, ANG2, MMP9), inflammation (IL-1β, TNF-α), gap junction communication (CX43), and cytoskeletal regulation (ROCK1), with the most prominent effects seen with exosomes from pericyte-like immortalized adipose-mesenchymal stem cells. High glucose increased the expression of pro-angiogenic and pro-inflammatory markers, which were effectively normalized post-exosome treatment. In conclusion, this research highlights the reparative capacity of exosomes secreted by pericyte-like differentiated immortalized adipose-mesenchymal stem cells in reversing the detrimental effects of high glucose on retinal microvascular endothelial cells. By reducing apoptosis, oxidative stress, inflammation, and abnormal angiogenic behavior, these exosomes present a promising avenue for therapeutic intervention in early diabetic retinopathy. Future studies can focus on elucidating the precise molecular mechanisms and exploring their translational potential in vivo.

Advances in Extracellular-Vesicles-Based Diagnostic and Therapeutic Approaches for Ocular Diseases

Extracellular vesicles (EVs) are nanoscale membrane vesicles of various sizes that can be secreted by most cells. EVs contain a diverse array of cargo, including RNAs, lipids, proteins, and other molecules with functions of intercellular communication, immune modulation, and regulation of physiological and pathological processes. The biofluids in the eye, including tears, aqueous humor, and vitreous humor, are important sources for EV-based diagnosis of ocular disease. Because the molecular cargos may reflect the biology of their parental cells, EVs in these biofluids, as well as in the blood, have been recognized as promising candidates as biomarkers for early diagnosis of ocular disease. Moreover, EVs have also been used as therapeutics and targeted drug delivery nanocarriers in many ocular disorders because of their low immunogenicity and superior biocompatibility in nature. In this review, we provide an overview of the recent advances in the field of EV-based studies on the diagnosis and therapeutics of ocular disease. We summarized the origins of EVs applied in ocular disease, assessed different methods for EV isolation from ocular biofluid samples, highlighted bioengineering strategies of EVs as drug delivery systems, introduced the latest applications in the diagnosis and treatment of ocular disease, and presented their potential in the current clinical trials. Finally, we briefly discussed the challenges of EV-based studies in ocular disease and some issues of concern for better focusing on clinical translational studies of EVs in the future.

Advancing osteoarthritis therapy with GMOCS hydrogel-loaded BMSCs-exos

This study investigated the mechanism of the extracellular matrix-mimicking hydrogel-mediated TGFB1/Nrf2 signaling pathway in osteoarthritis using bone marrow mesenchymal stem cell-derived exosomes (BMSCs-Exos). A GMOCS-Exos hydrogel was synthesized and evaluated for its impact on chondrocyte viability and neutrophil extracellular traps (NETs) formation. In an OA rat model, GMOCS-Exos promoted cartilage regeneration and inhibited NETs formation. Transcriptome sequencing identified TGFB1 as a key gene, with GMOCS-Exos activating Nrf2 signaling through TGFB1. Depletion of TGFB1 hindered the cartilage-protective effect of GMOCS-Exos. This study sheds light on a promising therapeutic strategy for osteoarthritis through GMOCS-Exos-mediated TGFB1/Nrf2 pathway modulation.

Advances in the study of microparticles in diabetic retinopathy

Diabetic retinopathy (DR) is one of the common diabetic microangiopathies, which severely impairs vision in diabetic population. The underlying mechanisms regarding the development of DR are not fully understood, and there is a lack of biomarkers to guide clinical, assessment of disease progression. Recently researchers have found that microparticles (MP) and its bioactive molecules are involved in the development of DR. MP is widely distributed in the circulation and can exert autocrine and paracrine benefits in intercellular signalling, provide a catalytic platform for the thrombospondin complex to promote coagulation, and promote the accumulation of reactive oxygen species to cause endothelial damage. MP interacts with advanced glycosylation end products (AGE) and AGE receptor (RAGE) to activate inflammatory pathways. MP carries a variety of miRNAs that regulate the vascular endothelial growth factor generation pathway. MP has also been applied to the exploration of mesenchymal stromal cell replacement therapy to treat DR. In a word, MP provides new ideas for the study of DR. MP has emerged as a marker to assess the progression of DR. As a potential therapeutic target, MP also has considerable research value.

Mesenchymal stem cells-derived exosomes alleviate senescence of retinal pigment epithelial cells by activating PI3K/AKT-Nrf2 signaling pathway in early diabetic retinopathy

Diabetic retinopathy (DR) is a major cause of vision loss and blindness in adults. Cellular senescence was involved in the pathogenesis of early-stage DR and is positively correlated with progression. Thus, our study aimed at exploring the effect and potential mechanism of Mesenchymal stem cells-derived exosomes (MSCs-EXOs) on Retinal Pigment Epithelial (RPE) cells senescence at an early stage of DR in vivo and in vitro. ARPE-19 cells were incubated in high glucose (HG) medium mixed with MSCs-EXOs to observe the changes in cell viability. Senescence-associated β-galactosidase (SA-β-gal) staining, Western blot and qRT-PCR were used to assess the expression of senescence-related genes and antioxidant mediators. Quantitative Real-Time polymerase chain reaction (qRT-PCR), Optical coherence tomography (OCT) Hematoxylin and eosin (HE) staining and Electroretinogram (ERG) were respectively used to verify cellular senescence, the structure and function of the retina. Our findings demonstrated that MSCs-EXOs inhibited HG-induced senescence in ARPE-19 cells. Furthermore, MSCs-EXOs reduced HG-induced cell apoptosis and oxidative stress levels while promoting cell proliferation. Mechanistically, HG suppressed PI3K/AKT phosphorylation as well as nuclear factor erythroid 2-related factor 2 (Nrf2) expression along with its downstream target gene expression in ARPE-19 cells. However, MSCs-EXOs reversed these changes by alleviating cellular senescence while enhancing antioxidant activity. In line with our results in vitro, MSCs-EXOs significantly ameliorated hyperglycemia-induced senescence in DR mice by downregulating mRNA expression of P53, P21, P16, and SASP. Additionally, MSCs-EXOs improved the functional and structural integrity of the retina in DR mice. Our study revealed the protective effect of MSCs-EXOs on cellular senescence, offering new insights for the treatment of DR.

A comprehensive review of engineered exosomes from the preparation strategy to therapeutic applications

Exosomes exhibit high bioavailability, biological stability, targeted specificity, low toxicity, and low immunogenicity in shuttling various bioactive molecules such as proteins, lipids, RNA, and DNA. Natural exosomes, however, have limited production, targeting abilities, and therapeutic efficacy in clinical trials. On the other hand, engineered exosomes have demonstrated long-term circulation, high stability, targeted delivery, and efficient intracellular drug release, garnering significant attention. The engineered exosomes bring new insights into developing next-generation drug delivery systems and show enormous potential in therapeutic applications, such as tumor therapies, diabetes management, cardiovascular disease, and tissue regeneration and repair. In this review, we provide an overview of recent advancements associated with engineered exosomes by focusing on the state-of-the-art strategies for cell engineering and exosome engineering. Exosome isolation methods, including traditional and emerging approaches, are systematically compared along with advancements in characterization methods. Current challenges and future opportunities are further discussed in terms of the preparation and application of engineered exosomes.

Mechanistic and therapeutic perspectives of non-coding RNA-modulated apoptotic signaling in diabetic retinopathy

Diabetic retinopathy (DR), a significant and vision-endangering complication associated with diabetes mellitus, constitutes a substantial portion of acquired instances of preventable blindness. The progression of DR appears to prominently feature the loss of retinal cells, encompassing neural retinal cells, pericytes, and endothelial cells. Therefore, mitigating the apoptosis of retinal cells in DR could potentially enhance the therapeutic approach for managing the condition by suppressing retinal vascular leakage. Recent advancements have highlighted the crucial regulatory roles played by non-coding RNAs (ncRNAs) in diverse biological processes. Recent advancements have highlighted that non-coding RNAs (ncRNAs), including microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs), act as central regulators in a wide array of biogenesis and biological functions, exerting control over gene expression associated with histogenesis and cellular differentiation within ocular tissues. Abnormal expression and activity of ncRNAs has been linked to the regulation of diverse cellular functions such as apoptosis, and proliferation. This implies a potential involvement of ncRNAs in the development of DR. Notably, ncRNAs and apoptosis exhibit reciprocal regulatory interactions, jointly influencing the destiny of retinal cells. Consequently, a thorough investigation into the complex relationship between apoptosis and ncRNAs is crucial for developing effective therapeutic and preventative strategies for DR. This review provides a fundamental comprehension of the apoptotic signaling pathways associated with DR. It then delves into the mutual relationship between apoptosis and ncRNAs in the context of DR pathogenesis. This study advances our understanding of the pathophysiology of DR and paves the way for the development of novel therapeutic strategies.

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.

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.

Advances in Research Related to MicroRNA for Diabetic Retinopathy

Diabetic retinopathy (DR) is a severe microvascular complication of diabetes and is one of the primary causes of blindness in the working-age population in Europe and the United States. At present, no cure is available for DR, but early detection and timely intervention can prevent the rapid progression of the disease. Several treatments for DR are known, primarily ophthalmic treatment based on glycemia, blood pressure, and lipid control, which includes laser photocoagulation, glucocorticoids, vitrectomy, and antivascular endothelial growth factor (anti-VEGF) medications. Despite the clinical efficacy of the aforementioned therapies, none of them can entirely shorten the clinical course of DR or reverse retinopathy. MicroRNAs (miRNAs) are vital regulators of gene expression and participate in cell growth, differentiation, development, and apoptosis. MicroRNAs have been shown to play a significant role in DR, particularly in the molecular mechanisms of inflammation, oxidative stress, and neurodegeneration. The aim of this review is to systematically summarize the signaling pathways and molecular mechanisms of miRNAs involved in the occurrence and development of DR, mainly from the pathogenesis of oxidative stress, inflammation, and neovascularization. Meanwhile, this article also discusses the research progress and application of miRNA-specific therapies for DR.

Non-coding RNAs and exosomal non-coding RNAs in diabetic retinopathy: A narrative review

Diabetic retinopathy (DR) is a devastating complication of diabetes, having extensive and resilient effects on those who suffer from it. As yet, the underlying cell mechanisms of this microvascular disorder are largely unclear. Recently, growing evidence suggests that epigenetic mechanisms can be responsible for gene deregulation leading to the alteration of key processes in the development and progression of DR, in addition to the widely recognized pathological mechanisms. It is noteworthy that seemingly unending epigenetic modifications, caused by a prolonged period of hyperglycemia, may be a prominent factor that leads to metabolic memory, and brings epigenetic entities such as non-coding RNA into the equation. Consequently, further investigation is necessary to truly understand this mechanism. Exosomes are responsible for carrying signals from cells close to the vasculature that are participating in abnormal signal transduction to faraway organs and cells by sailing through the bloodstream. These signs indicate metabolic disorders. With the aid of their encased structure, they can store diverse signaling molecules, which then can be dispersed into the blood, urine, and tears. Herein, we summarized various non-coding RNAs (ncRNAs) that are related to DR pathogenesis. Moreover, we highlighted the role of exosomal ncRNAs in this disease.

Exosomes derived from BMSCs alleviates high glucose-induced diabetic retinopathy via carrying miR-483-5p

Diabetic retinopathy (DR) is a progressive disease which can cause health problem. It has been reported that bone marrow mesenchymal stem cells (BMSCs)-secreted exosomes could regulate the progression of DR via carrying microRNAs. Meanwhile, miR-483-5p was downregulated in DR; however, whether BMSCs-secreted exosomes can modulate DR progression via carrying miR-483-5p remains unclear. To mimic DR in vitro, ARPE-19 cells were exposed to 30 mM high glucose (HG). Exosomes were isolated from BMSCs and identified by transmission electron microscopy, nanoparticle tracking analysis, and western blot. Cell counting kit-8 assay was applied for assessing the cell viability. Flow cytometry was applied to test the cell apoptosis. Meanwhile, dual luciferase assay was used to evaluate the association among miR-483-5p and downstream target insulin-like growth factor 1 receptor (IGF-1R). In addition, quantitative reverse-transcription polymerase chain reaction and western blot were used for exploring the level of miR-483-5p and IGF-1R. HG significantly induced apoptosis in ARPE-19 cells, while BMSCs-derived exosomes reversed this phenomenon. In addition, inhibition of miR-483-5p expression of exosomes further aggravated HG-induced ARPE-19 cell apoptosis. Meanwhile, IGF-1R was the downstream messenger RNA of miR-483-5p, and IGF-1R silencing could reverse the effect of exosomes with downregulated miR-483-5p on HG-induced cell injury. Exosomes derived from BMSCs inhibit the progression of DR via carrying miR-483-5p. Thus, our study might provide a theoretical basis for discovering new strategies against DR.

Diabetic and nondiabetic BMSC-derived exosomes affect bone regeneration via regulating miR-17-5p/SMAD7 axis

Diabetic bone disease (DBD) is a complication of diabetes mellitus (DM) and is characterized by impaired osteocyte function and delayed bone remodeling due to high blood glucose levels and sustained release of inflammatory factors. Recent studies show that the regulation of osteoblasts (OBs) by bone marrow stromal cells (BMSCs) is an important mechanism in alleviating DBD and that exosomes are recognized as the key medium. Mesenchymal stem cell-derived exosome (MSC-Exos) therapy is a promising approach to facilitate tissue repair. However, the influence of exosomes from diabetic conditioned BMSCs on OBs and bone regeneration, as well as the underlying mechanism, are still elusive. Here, we used high-glucose medium to mimic diabetic conditions and normal-glucose medium as control to mimic nondiabetic conditions in vitro and found that microRNA-17 (miR-17) was downregulated in diabetic-conditioned BMSC-derived exosomes (HG-Exos), HG-Exo-co-cultured osteoblasts, and the skull of rats with type 2 diabetes mellitus (T2DM). Further experiment concluded that nondiabetic conditioned BMSC-Exos (NG-Exos) promoted the osteogenesis of OBs and bone regeneration of rats with T2DM via upregulation of miR-17. Compare with NG-Exos, HG-Exos impeded osteogenesis of OBs in vitro and bone regeneration of rats in vivo by downregulation of miR-17. Moreover, miR-17 promoted bone regeneration by targeting SMAD7, which was further proved to have a negative effect on osteogenesis. Taken together, nondiabetic BMSC-derived exosomes greatly foster bone regeneration, whereas diabetic BMSC-derived exosomes undermine the promotion effect of MSC-Exos by regulating the miR-17/SMAD7 axis. These findings provide support for the miR-17-5p/SMAD7 axis as a promising therapeutic target to treat DBD.

Therapeutic Potential of Mesenchymal Stem Cell‐Derived Conditioned Medium for Diabetes Mellitus and Related Complications

Diabetes mellitus (DM) is one of the most life‐threatening metabolic disorders, with 9% of the global prevalence, and it is estimated to be rising to 12.2% in 2045. Currently, there is no definitive treatment for DM. Although life‐saving, insulin administration to control blood sugar is not a cure for DM and is insufficient to prevent DM‐related complications such as nephropathy, neuropathy, or retinopathy. For this reason, studies are continuing to develop treatments that will provide β‐cell regeneration while suppressing autoimmunity. Mesenchymal stem cells (MSCs) are multipotent stem cells with a high proliferation capacity, immunosuppression, and immunomodulation ability. MSCs have gained therapeutic importance with these properties besides their differentiation ability. The immunosuppressive and immunomodulatory properties of the cells arise from the soluble and insoluble factors they secrete into the extracellular environment. Therefore, the culture medium where these cells grow has therapeutic value and is named conditioned medium (CM). In this context, CM obtained from MSCs can provide a similar therapeutic effect with fewer safety concerns. Furthermore, preconditioning of MSCs can improve the effectiveness of these cells and associated cellular products. So, this review summarizes the recent advances in MSC‐derived CMs and their therapeutic potential for DM and related complications.

The ideal treatment timing for diabetic retinopathy: the molecular pathological mechanisms underlying early-stage diabetic retinopathy are a matter of concern

Diabetic retinopathy (DR) is a prevalent complication of diabetes, significantly impacting patients' quality of life due to vision loss. No pharmacological therapies are currently approved for DR, excepted the drugs to treat diabetic macular edema such as the anti-VEGF agents or steroids administered by intraocular route. Advancements in research have highlighted the crucial role of early intervention in DR for halting or delaying disease progression. This holds immense significance in enhancing patients' quality of life and alleviating the societal burden associated with medical care costs. The non-proliferative stage represents the early phase of DR. In comparison to the proliferative stage, pathological changes primarily manifest as microangiomas and hemorrhages, while at the cellular level, there is a loss of pericytes, neuronal cell death, and disruption of components and functionality within the retinal neuronal vascular unit encompassing pericytes and neurons. Both neurodegenerative and microvascular abnormalities manifest in the early stages of DR. Therefore, our focus lies on the non-proliferative stage of DR and we have initially summarized the mechanisms involved in its development, including pathways such as polyols, that revolve around the pathological changes occurring during this early stage. We also integrate cutting-edge mechanisms, including leukocyte adhesion, neutrophil extracellular traps, multiple RNA regulation, microorganisms, cell death (ferroptosis and pyroptosis), and other related mechanisms. The current status of drug therapy for early-stage DR is also discussed to provide insights for the development of pharmaceutical interventions targeting the early treatment of DR.

Converging protective pathways: Exploring the linkage between physical exercise, extracellular vesicles and oxidative stress

Physical Exercise (EXR) has been shown to have numerous beneficial effects on various systems in the human body. It leads to a decrease in the risk of mortality from chronic diseases, such as cardiovascular disease, cancer, metabolic and central nervous system disorders. EXR results in improving cardiovascular fitness, cognitive function, immune activity, endocrine action, and musculoskeletal health. These positive effects make EXR a valuable intervention for promoting overall health and well-being in individuals of all ages. These beneficial effects are partially mediated by the role of the regular EXR in the adaptation to redox homeostasis counteracting the sudden increase of ROS, the hallmark of many chronic diseases. EXR can trigger the release of numerous humoral factors, e.g. protein, microRNA (miRs), and DNA, that can be shuttled as cargo of Extracellular vesicles (EVs). EVs show different cargo modification after oxidative stress stimuli as well as after EXR. In this review, we aim to highlight the main studies on the role of EVs released during EXR and oxidative stress conditions in enhancing the antioxidant enzymes pathway and in the decrease of oxidative stress environment mediated by their cargo.

Research progress on the pathogenesis of diabetic retinopathy

Diabetic retinopathy is one of the most common and serious microvascular complications of diabetes mellitus. There are many factors leading to diabetic retinopathy, and its pathogenesis is still unclear. At present, there are still no effective measures for the early treatment of diabetic retinopathy, and the treatment options available when diabetes progresses to advanced stages are very limited, and the treatment results are often unsatisfactory. Detailed studies on the molecular mechanisms of diabetic retinopathy pathogenesis and the development of new therapeutic agents are of great importance. This review describes the potential pathogenesis of diabetic retinopathy for experimental studies and clinical practice.

Oxidative Stress and Its Regulation in Diabetic Retinopathy

Diabetic retinopathy is the retinal disease associated with hyperglycemia in patients who suffer from type 1 or type 2 diabetes. It includes maculopathy, involving the central retina and characterized by ischemia and/or edema, and peripheral retinopathy that progresses to a proliferative stage with neovascularization. Approximately 10% of the global population is estimated to suffer from diabetes, and around one in 5 of these individuals have diabetic retinopathy. One of the major effects of hyperglycemia is oxidative stress, the pathological state in which elevated production of reactive oxygen species damages tissues, cells, and macromolecules. The retina is relatively prone to oxidative stress due to its high metabolic activity. This review provides a summary of the role of oxidative stress in diabetic retinopathy, including a description of the retinal cell players and the molecular mechanisms. It discusses pathological processes, including the formation and effects of advanced glycation end-products, the impact of metabolic memory, and involvements of non-coding RNA. The opportunities for the therapeutic blockade of oxidative stress in diabetic retinopathy are also considered.

A bibliometric systematic review of extracellular vesicles in eye diseases from 2003 to 2022

BACKGROUND

Extracellular vesicles (EVs) have emerged as a valuable and promising research field in eye diseases. However, there are few bibliometric studies in this area. The purpose of this study was to employ bibliometric analysis to visualize the research hotspots and trends of EVs in eye diseases and provide researchers with new perspectives for further studies.

METHODS

Articles and reviews on EVs in eye diseases published between January 1, 2003 and December 31, 2022 were retrieved from the Web of Science Core Collection. Qualitative and quantitative analysis was performed using Microsoft Excel and CiteSpace software.

RESULTS

In total, 790 articles were included in the analysis. Over the past 2 decades, there has been a significant increase in the number of publications on the study of EVs in eye diseases. The United States, China, and Italy made the most significant contributions to this field. The Chinese Academy of Sciences was the most productive institution, and International Journal of Molecular Sciences published the most number of articles. Proceedings of the National Academy of Sciences of the United States of America had the highest citation frequency. Beit-Yannai E had the highest output and Thery C had the highest average citation frequency among authors. The analysis of keywords revealed that the neuroprotective effects of stem cell-derived EVs and biomarkers of eye diseases are current research hotspots and frontiers in this field.

CONCLUSION

This study provides a scientific perspective on EVs in eye diseases and provides valuable information for researchers to detect current research conditions, hotspots, and emerging trends for further study.

Exosomal non-coding RNAs in angiogenesis: Functions, mechanisms and potential clinical applications

Exosomes are extracellular vesicles that can be produced by most cells. Exosomes act as important intermediaries in intercellular communication, and participate in a variety of biological activities between cells. Non-coding RNAs (ncRNAs) usually refer to RNAs that do not encode proteins. Although ncRNAs have no protein-coding capacity, they are able to regulate gene expression at multiple levels. Angiogenesis is the formation of new blood vessels from pre-existing vessels, which is an important physiological process. However, abnormal angiogenesis could induce many diseases such as atherosclerosis, diabetic retinopathy and cancer. Many studies have shown that ncRNAs can stably exist in exosomes and play a wide range of physiological and pathological roles including regulation of angiogenesis. In brief, some specific ncRNAs can be enriched in exosomes secreted by cells and absorbed by recipient cells through the exosome pathway, thus activating relevant signaling pathways in target cells and playing a role in regulating angiogenesis. In this review, we describe the physiological and pathological functions of exosomal ncRNAs in angiogenesis, summarize their role in angiogenesis-related diseases, and illustrate potential clinical applications like novel drug therapy strategies and diagnostic markers in exosome research as inspiration for future investigations.

Pathological role of inflammation in ocular disease progress and its targeting by mesenchymal stem cells (MSCs) and their exosome; current status and prospect

Because of their unique capacity for differentiation to a diversity of cell lineages and immunosuppressive properties, mesenchymal stem cells (MSC) are being looked at as a potential new treatment option in ophthalmology. The MSCs derived from all tissue sources possess immunomodulatory attributes through cell-to-cell contact and releasing a myriad of immunomodulatory factors (IL-10, TGF-β, growth-related oncogene (GRO), indoleamine 2,3 dioxygenase (IDO), nitric oxide (NO), interleukin 1 receptor antagonist (IL-1Ra), prostaglandin E2 (PGE2)). Such mediators, in turn, alter both the phenotype and action of all immune cells that serve a pathogenic role in the progression of inflammation in eye diseases. Exosomes from MSCs, as natural nano-particles, contain the majority of the bioactive components of parental MSCs and can easily by-pass all biological barriers to reach the target epithelial and immune cells in the eye without interfering with nearby parenchymal cells, thus having no serious side effects. We outlined the most recent research on the molecular mechanisms underlying the therapeutic benefits of MSC and MSC-exosome in the treatment of inflammatory eye diseases in the current article.

Understanding the lncRNA/miRNA-NFκB regulatory network in Diabetes Mellitus: From function to clinical translation

Diabetes mellitus (DM) and its significant ramifications make out one of the primary reasons behind morbidity worldwide. Noncoding RNAs (ncRNAs), such as microRNAs and long noncoding RNAs, are involved in regulating manifold biological processes, including diabetes initiation and progression. One of the established pathways attributed to DM development is NF-κB signaling. Neurons, β cells, adipocytes, and hepatocytes are among the metabolic tissues where NF-κB is known to produce a range of inflammatory chemokines and cytokines. The direct or indirect role of ncRNAs such as lncRNAs and miRNAs on the NF-κB signaling pathway and DM development has been supported by many studies. As a result, effective diabetes treatment and preventive methods will benefit from a comprehensive examination of the interplay between NF-κB and ncRNAs. Herein, we provide a concise overview of the role of NF-κB-mediated signaling pathways in diabetes mellitus and its consequences. The reciprocal regulation of ncRNAs and the NF-κB signaling pathway in diabetes is then discussed, shedding light on the pathogenesis of the illness and its possible therapeutic interventions.

Suppressing Inflammation for the Treatment of Diabetic Retinopathy and Age-Related Macular Degeneration: Dazdotuftide as a Potential New Multitarget Therapeutic Candidate

Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are major causes of blindness globally. The primary treatment option for DME and neovascular AMD (nAMD) is anti-vascular endothelial growth factor (VEGF) compounds, but this treatment modality often yields insufficient results, and monthly injections can place a burden on the health system and patients. Although various inflammatory pathways and mediators have been recognized as key players in the development of DR and AMD, there are limited treatment options targeting these pathways. Molecular pathways that are interlinked, or triggers of multiple inflammatory pathways, could be promising targets for drug development. This review focuses on the role of inflammation in the pathogenesis of DME and AMD and presents current anti-inflammatory compounds, as well as a potential multitarget anti-inflammatory compound (dazdotuftide) that could be a candidate treatment option for the management of DME and AMD.

Extracellular-Vesicle-Based Therapeutics in Neuro-Ophthalmic Disorders

Extracellular vesicles (EVs) have been recognized as promising candidates for developing novel therapeutics for a wide range of pathologies, including ocular disorders, due to their ability to deliver a diverse array of bioactive molecules, including proteins, lipids, and nucleic acids, to recipient cells. Recent studies have shown that EVs derived from various cell types, including mesenchymal stromal cells (MSCs), retinal pigment epithelium cells, and endothelial cells, have therapeutic potential in ocular disorders, such as corneal injury and diabetic retinopathy. EVs exert their effects through various mechanisms, including promoting cell survival, reducing inflammation, and inducing tissue regeneration. Furthermore, EVs have shown promise in promoting nerve regeneration in ocular diseases. In particular, EVs derived from MSCs have been demonstrated to promote axonal regeneration and functional recovery in various animal models of optic nerve injury and glaucoma. EVs contain various neurotrophic factors and cytokines that can enhance neuronal survival and regeneration, promote angiogenesis, and modulate inflammation in the retina and optic nerve. Additionally, in experimental models, the application of EVs as a delivery platform for therapeutic molecules has revealed great promise in the treatment of ocular disorders. However, the clinical translation of EV-based therapies faces several challenges, and further preclinical and clinical studies are needed to fully explore the therapeutic potential of EVs in ocular disorders and to address the challenges for their successful clinical translation. In this review, we will provide an overview of different types of EVs and their cargo, as well as the techniques used for their isolation and characterization. We will then review the preclinical and clinical studies that have explored the role of EVs in the treatment of ocular disorders, highlighting their therapeutic potential and the challenges that need to be addressed for their clinical translation. Finally, we will discuss the future directions of EV-based therapeutics in ocular disorders. Overall, this review aims to provide a comprehensive overview of the current state of the art of EV-based therapeutics in ophthalmic disorders, with a focus on their potential for nerve regeneration in ocular diseases.

Extracellular vesicles: an emerging player in retinal homeostasis

Extracellular vesicles (EVs) encompass secreted membrane vesicles of varied sizes, including exosomes (-30-200 nm) and microvesicles (MVs) that are ∼100-1,000 nm in size. EVs play an important role in autocrine, paracrine, and endocrine signaling and are implicated in myriad human disorders including prominent retinal degenerative diseases, like age related macular degeneration (AMD) and diabetic retinopathy (DR). Studies of EVs in vitro using transformed cell lines, primary cultures, and more recently, induced pluripotent stem cell derived retinal cell type(s) (e.g., retinal pigment epithelium) have provided insights into the composition and function of EVs in the retina. Furthermore, consistent with a causal role of EVs in retinal degenerative diseases, altering EV composition has promoted pro-retinopathy cellular and molecular events in both in vitro and in vivo models. In this review, we summarize the current understanding of the role of EVs in retinal (patho)physiology. Specifically, we will focus on disease-associated EV alterations in specific retinal diseases. Furthermore, we discuss the potential utility of EVs in diagnostic and therapeutic strategies for targeting retinal diseases.

Mesenchymal Stem Cell-Derived Exosomes in Ophthalmology: A Comprehensive Review

Over the past decade, the field of mesenchymal stem cell (MSC) therapy has exhibited rapid growth. Due to their regenerative, reparatory, and immunomodulatory capacities, MSCs have been widely investigated as therapeutic agents in the cell-based treatment of chronic ophthalmic pathologies. However, the applicability of MSC-based therapy is limited by suboptimal biocompatibility, penetration, and delivery to the target ocular tissues. An emerging body of research has elucidated the role of exosomes in the biological functions of MSCs, and that MSC-derived extracellular vesicles (EVs) possess anti-inflammatory, anti-apoptotic, tissue repairing, neuroprotective, and immunomodulatory properties similar to MSCs. The recent advances in MSCs-derived exosomes can serve as solutions to the challenges faced by MSCs-therapy. Due to their nano-dimensions, MSC-derived exosomes can rapidly penetrate biological barriers and reach immune-privileged organs, allowing for efficient delivery of therapeutic factors such as trophic and immunomodulatory agents to ocular tissues that are typically challenging to target by conventional therapy and MSCs transplantation. In addition, the use of EVs minimizes the risks associated with mesenchymal stem cell transplantation. In this literature review, we focus on the studies published between 2017 and 2022, highlighting the characteristics of EVs derived from MSCs and their biological functions in treating anterior and posterior segment ocular diseases. Additionally, we discuss the potential use of EVs in clinical settings. Rapid advancements in regenerative medicine and exosome-based drug delivery, in conjunction with an increased understanding of ocular pathology and pharmacology, hold great promise for the treatment of ocular diseases. The potential of exosome-based therapies is exciting and can revolutionize the way we approach these ocular conditions.

Research progress of exosomes as drug carriers in cancer and inflammation

Extracellular vesicles (EVs) could be produced by most cells and play an important role in disease development. As a subtype of EVs, exosomes exhibit suitable size, rich surface markers and diverse contents, making them more appealing as potential drug carriers. Compared with traditional synthetic nanoparticles, exosomes possess superior biocompatibility and much lower immunogenicity. This work reviewed the most up-to-date research progress of exosomes as carriers for nucleic acids, proteins and small molecule drugs for cancer and inflammation management. The drug loading strategies and potential cellular uptake behaviour of exosomes are highlighted, trying to provide reference for future exosome design and application.

Diagnosis potential of subarachnoid hemorrhage using miRNA signatures isolated from plasma-derived extracellular vesicles

The diagnosis and clinical management of aneurysmal subarachnoid hemorrhage (aSAH) is currently limited by the lack of accessible molecular biomarkers that reflect the pathophysiology of disease. We used microRNAs (miRNAs) as diagnostics to characterize plasma extracellular vesicles in aSAH. It is unclear whether they can diagnose and manage aSAH. Next-generation sequencing (NGS) was used to detect the miRNA profile of plasma extracellular vesicles (exosomes) in three patients with SAH and three healthy controls (HCs). We identified four differentially expressed miRNAs and validated the results using quantitative real-time polymerase chain reaction (RT-qPCR) with 113 aSAH patients, 40 HCs, 20 SAH model mice, and 20 sham mice. Exosomal miRNA NGS revealed that six circulating exosomal miRNAs were differentially expressed in patients with aSAH versus HCs and that the levels of four miRNAs (miR-369-3p, miR-410-3p, miR-193b-3p, and miR-486-3p) were differentially significant. After multivariate logistic regression analysis, only miR-369-3p, miR-486-3p, and miR-193b-3p enabled prediction of neurological outcomes. In a mouse model of SAH, greater expression of miR-193b-3p and miR-486-3p remained statistically significant relative to controls, whereas expression levels of miR-369-3p and miR-410-3p were lower. miRNA gene target prediction showed six genes associated with all four of these differentially expressed miRNAs. The circulating exosomes miR-369-3p, miR-410-3p, miR-193b-3p, and miR-486-3p may influence intercellular communication and have potential clinical utility as prognostic biomarkers for aSAH patients.

Study on the regulatory effect of Panax notoginseng saponins combined with bone mesenchymal stem cell transplantation on IRAK1/TRAF6-NF-κB pathway in patients with diabetic cutaneous ulcers

Panax notoginseng saponins (PNSs) have been found as the major active ingredient of Panax notoginseng (Burkill) F.H.Chen (PN) leaves, which has the effect of reducing inflammatory response, facilitating fibroblast proliferation, as well as promoting angiogenesis. This study aimed to investigate the molecular basis of PNS combined with bone mesenchymal stem cells (BMSCs) for treating diabetic cutaneous ulcers (DCU) and its mechanism of action.

METHODS

A total of 75 SD rats were selected to make diabetic cutaneous ulcers model. According random number table method, the rats were randomly divided into a control group, a DCU group, a BMSCs group, a PNS group and BMSCs + PNS group. Five groups of rats were given without treatment. After being treated for 7 days, the rats were anesthetized with pentobarbital, and granulation tissue was collected from the central point of the wound. They were used for pathological analysis, Western blot (WB) and polymerase chain reaction (PCR) assays.

RESULTS

The wound healing area was the largest in the BMSCs + PNS group. HE staining results showed that the PNS + BMSCs group could promote the formation of new epidermis and reduce the infiltration of inflammatory cells. Immunohistochemistry (IHC) results showed that the PNS + BMSCs group could up-regulate the expression of Ki67 protein and cell proliferation. In addition, PNS combined with BMSCs up-regulated the expression of miR-146-5p and down-regulated the expression of IL-1β, IL-6 and TNF-α, IRAK1, TRAF6 and p65 in the NF-κB signaling pathway (p < 0.05).

CONCLUSIONS

PNS combined with bone mesenchymal stem cell transplantation up-regulated miR-146a-5p targeting and binding to IRAK1/TRAF6, inhibiting the activation of NF-κB pathway, which reduced the inflammatory response of DCU and facilitated the skin healing of DCU. Thus, this study provides a theoretical basis and a novel therapeutic option for the treatment of DFU with PNS combined with BMSCs.

Extracellular vesicles derived from different sources play various roles in diabetic retinopathy

Extracellular vesicles (EVs) are present in almost all biological fluids and secreted by almost all cell types. A growing number of studies have revealed the potential roles of EVs in the diagnosis and treatment of the diabetic retinopathy (DR). Changes in the quantity and content of EVs may serve as biomarkers of cause or consequence of pathological status of DR, such as inflammation, neovascularization and epithelial-mesenchymal transition. In addition, as natural, safe and efficient drug carrier, EVs have been reported to play important roles in intercellular communication by acting for essential cell-specific information to target cells. In this review, we summarize the roles of EVs, secreted by various types of cells and participated in various biological processes, in the pathogenesis, diagnosis, and treatment of DR.

Stem Cell-Derived Extracellular Vesicles as a Potential Therapeutic Tool for Eye Diseases: From Benchtop to Bedside

Stem cell-derived extracellular vesicles (SC-EVs) have remarkably drawn clinicians' attention in treating ocular diseases. As a paracrine factor of stem cells and an appealing alternative for off-the-shelf cell-free therapeutics, SC-EVs can be conveniently applied topically on the ocular surface or introduced to the retina via intravitreal injection, without increasing the risks of immunogenesis or oncogenesis. This chapter aims to assess the potential applications for EV, obtained from various types of stem cells, in myriad eye diseases (traumatic, inflammatory, degenerative, immunological, etc.). To the best of our knowledge, all relevant pre-clinical studies are summarized here. Furthermore, we highlight the up-to-date status of clinical trials in the same realm and emphasize where future research efforts should be directed. For a successful clinical translation, various drawbacks of EVs therapy should be overcome (e.g., contamination, infection, insufficient yield, etc.). Moreover, standardized, and scalable extraction, purification, and characterization protocols are highly suggested to determine the exosome quality before they are offered to patients with ocular disorders.

Noncoding RNAs Are Promising Therapeutic Targets for Diabetic Retinopathy: An Updated Review (2017-2022)

Diabetic retinopathy (DR) is the most common complication of diabetes. It is also the main cause of blindness caused by multicellular damage involving retinal endothelial cells, ganglial cells, and pigment epithelial cells in adults worldwide. Currently available drugs for DR do not meet the clinical needs; thus, new therapeutic targets are warranted. Noncoding RNAs (ncRNAs), a new type of biomarkers, have attracted increased attention in recent years owing to their crucial role in the occurrence and development of DR. NcRNAs mainly include microRNAs, long noncoding RNAs, and circular RNAs, all of which regulate gene and protein expression, as well as multiple biological processes in DR. NcRNAs, can regulate the damage caused by various retinal cells; abnormal changes in the aqueous humor, exosomes, blood, tears, and the formation of new blood vessels. This study reviews the different sources of the three ncRNAs-microRNAs, long noncoding RNAs, and circular RNAs-involved in the pathogenesis of DR and the related drug development progress. Overall, this review improves our understanding of the role of ncRNAs in various retinal cells and offers therapeutic directions and targets for DR treatment.

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.

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.

The Correlation Between MicroRNAs and Diabetic Retinopathy

Micro ribonucleic acids (miRNAs), as a category of post-transcriptional gene inhibitors, have a wide range of biological functions, are involved in many pathological processes, and are attractive therapeutic targets. Considerable evidence in ophthalmology indicates that miRNAs play an important role in diabetic retinopathy (DR), especially in inflammation, oxidative stress, and neurodegeneration. Targeting specific miRNAs for the treatment of DR has attracted much attention. This is a review focusing on the pathophysiological roles of miRNAs in DR, diabetic macular edema, and proliferative DR complex multifactorial retinal diseases, with particular emphasis on how miRNAs regulate complex molecular pathways and underlying pathomechanisms. Moreover, the future development potential and application limitations of therapy that targets specific miRNAs for DR are discussed.

Experiment-Based Interventions to Diabetic Retinopathy: Present and Advances

Diabetic retinopathy is the major blinding disease among working-age populations, which is becoming more significant due to the growth of diabetes. The metabolic-induced oxidative and inflammatory stress leads to the insult of neovascular unit, resulting in the core pathophysiology of diabetic retinopathy. Existing therapies focus on the inflammation, oxidation, and angiogenesis phenomena of diabetic retinopathy, without effect to radically cure the disease. This review also summarizes novel therapeutic attempts for diabetic retinopathy along with their advantages and disadvantages, mainly focusing on those using cellular and genetic techniques to achieve remission on a fundamental level of disease.

CircZNF532 knockdown protects retinal pigment epithelial cells against high glucose-induced apoptosis and pyroptosis by regulating the miR-20b-5p/STAT3 axis

INTRODUCTION

The loss of retinal pigment epithelial (RPE) cells is associated with the etiology of diabetic retinopathy (DR). This study investigated the effects of circular RNA ZNF532 (circZNF532) on apoptosis and pyroptosis of RPE cells.

MATERIALS AND METHODS

Blood samples were collected from patients with DR and healthy volunteers. A human RPE cell line ARPE-19 was induced by high glucose (HG) and assayed for cell viability, apoptosis, and pyroptosis. The binding of miR-20b-5p with circZNF532 and STAT3 was confirmed by a luciferase activity assay. A mouse model of diabetic retinopathy was established.

RESULTS

CircZNF532 and STAT3 were upregulated but miR-20b-5p was downregulated in the serum samples of patients with DR and HG-induced ARPE-19 cells. Elevated miR-20b-5p or CircZNF532 knockdown enhanced proliferation but reduced apoptosis and pyroptosis of ARPE-19 cells. CircZNF532 sponged miR-20b-5p and inhibited its expression. STAT3 was verified as a target of miR-20b-5p. MiR-20b-5p modulated ARPE-19 cell viability, apoptosis, and pyroptosis by targeting STAT3. Mice with STZ-induced diabetes showed elevated expressions of circZNF532 and STAT3 but decreased the level of miR-20b-5p compared with the controls. Knockdown of circZNF532 inhibited apoptosis and pyroptosis in mouse retinal tissues.

CONCLUSION

CircZNF532 knockdown rescued human RPE cells from HG-induced apoptosis and pyroptosis by regulating STAT3 via miR-20b-5p.

Exosomes Derived From Human Gingival Mesenchymal Stem Cells Attenuate the Inflammatory Response in Periodontal Ligament Stem Cells

This study aimed to explore the effects of exosomes derived from human gingival mesenchymal stem cells (GMSC-Exo) on the inflammatory response of periodontal ligament stem cells (PDLSCs) in an inflammatory microenvironment in order to restore the regenerative potential of PDLSCs, which promotes periodontal tissue regeneration in patients with periodontitis. Periodontitis is a chronic infectious disease characterized by periodontal tissue inflammation and alveolar bone destruction. PDLSCs are regarded as promising seed cells for restoring periodontal tissue defects because of their ability to regenerate cementum/PDL-like tissue and alveolar bone. However, PDLSCs in the inflammatory environment show significantly attenuated regenerative potential. GMSC-Exo have been reported to have anti-inflammatory and immunosuppressive properties. In this study, we investigated the effects of GMSC-Exo on the inflammatory response of PDLSCs induced by lipopolysaccharides (LPS). LPS was used to simulate the inflammatory microenvironment of periodontitis in vitro. GMSC-Exo were extracted from the culture supernatant of GMSCs by ultracentrifugation. We found that GMSC-Exo attenuated the inflammatory response of PDLSCs induced by LPS. Furthermore, compared to treatment with LPS, treatment with GMSC-Exo attenuated the expression of NF-κB signaling and Wnt5a in LPS-induced PDLSCs. In conclusion, we confirmed that GMSC-Exo could suppress the inflammatory response of PDLSCs by regulating the expression of NF-κB signaling and Wnt5a, which paves the way for the establishment of a therapeutic approach for periodontitis.