Exosomes: Potential Disease Biomarkers and New Therapeutic Targets

Advancing Alzheimer's disease therapy through engineered exosomal Macromolecules

Exosomes are a subject of continuous investigation due to their function as extracellular vesicles (EVs) that significantly contribute to the pathophysiology of certain neurodegenerative disorders (NDD), including Alzheimer's disease (AD). Exosomes have shown the potential to carry both therapeutic and pathogenic materials; hence, researchers have used exosomes for medication delivery applications. Exosomes have reduced immunogenicity when used as natural drug delivery vehicles. This guarantees the efficient delivery of the medication without causing significant side reactions. Exosomes have lately enabled the potential for drug delivery in AD, along with promising future therapeutic uses for the detection of neurodegenerative disorders. Furthermore, exosomes have been examined for their prospective use in illness diagnosis and prediction before the manifestation of symptoms. This review will document prior studies and will concentrate on the rationale behind the substantial potential of exosomes in the treatment of AD and their prospective use as a diagnostic and predictive tool for this condition.

Exploring the role of exosomes in diabetic neuropathy: From molecular mechanisms to therapeutic potential

Diabetic neuropathy (DN) is a debilitating complication of diabetes mellitus (DM), characterized by progressive neuronal damage, sensory dysfunction, and impaired quality of life. Recent advances in exosome research have elucidated their crucial role in DN's pathogenesis, diagnosis, and treatment. Exosomes-nanoscale extracellular vesicles-function as vehicles for molecular cargo, including microRNAs (miRNAs), proteins, and lipids, which mediate intercellular communication and regulate key biological processes. Pathologically, hyperglycemia and hyperlipidemia induce the release of exosomes enriched with pathogenic miRNAs, such as miR-130a and miR-20b-3p, which disrupt neuronal function, axonal regeneration, and inflammatory pathways. Conversely, diagnostic studies highlight the utility of exosomal biomarkers like miR-7 and miR-221 in the early detection and monitoring of DN. Therapeutically, Schwann cell-derived and mesenchymal stromal cell (MSC)-derived exosomes demonstrate neuroprotective and reparative effects by enhancing mitochondrial function, modulating inflammation, and promoting axonal repair. Emerging approaches, including engineered exosomes and miRNA-enriched vesicles, further expand their therapeutic potential. Despite these advances, challenges such as standardization, large-scale production, and clinical validation remain in translating these findings into clinical practice. This review underscores the multifaceted roles of exosomes in DN and highlights their potential as innovative tools for precision diagnostics and targeted therapies, paving the way for future research and clinical applications.

Exosomal lncRNAs in the Tumor Angiogenesis: As Therapeutic Targets in Cancer Treatment

Exosomes, as mediators of intercellular communication, can be released from different types of cells and regulate the function of the target cell by transferring cargo, such as proteins, DNA, and RNA. Recent investigations have revealed a preponderance of long noncoding RNAs (lncRNAs), a subclass of noncoding RNAs, within exosomes, where they exhibit notable stability and are implicated in the development and progression of neoplastic processes, such as tumor angiogenesis. Angiogenesis, as a hallmark of cancer, provides diffusible nutrients and oxygen to the distant cells and guarantees tumorigenesis and metastasis. Exosomal lncRNAs, including MALAT1, OIP5-AS1, PART1, SNHG family, FAM225A, ATB, RAMP2-AS1, UCA1, TRPM2-AS, FGD5-AS1, and LINC0016, could modulate tumor angiogenesis by activating signaling cascades and mediators within the target cells, such as microRNAs (miRNAs). Regulation of tumor angiogenesis through modulation of exosomal lncRNAs could be a reliable strategy for cancer therapy. In this review, we discuss the characteristics and biogenesis of exosomes and lncRNAs and how exosomal lncRNAs are involved in various processes of tumorigenesis. Our primary focus is on exosomal lncRNAs, their impact on tumor angiogenesis, and their potential as novel diagnostic markers and therapeutic targets for various cancers.

The role of exosomes in diagnosis, pathophysiology, and management of Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder associated with impaired cognitive function and memory loss. Currently, available therapeutics can effectively alleviate the symptoms of AD, but there is a lack of treatment to halt the progression of the disease. In recent years, exosomes have gained much attention due to their involvement in various neurological disorders. Exosomes are small extracellular vesicles comprising lipids, proteins, DNA, non-coding RNA, and mRNAs, can carry various therapeutic molecules, and are potential drug delivery vehicles. Exosomes are known as a double-edged sword due to their involvement in both the pathogenesis and management of AD. This review explores the function of exosomes in the pathophysiology, treatment, and diagnosis of AD, also emphasizing their potential as a targeted drug delivery carrier to the brain. This review seeks to provide novel perspectives to understand better the onset, targeted treatment, and diagnosis of AD using exosomes.

The potential of exosomes in regenerative medicine and in the diagnosis and therapies of neurodegenerative diseases and cancer

Exosomes, nanosized extracellular vesicles released by various cell types, are intensively studied for the diagnosis and treatment of cancer and neurodegenerative diseases, and they also display high usability in regenerative medicine. Emphasizing their diagnostic potential, exosomes serve as carriers of disease-specific biomarkers, enabling non-invasive early detection and personalized medicine. The cargo loading of exosomes with therapeutic agents presents an innovative strategy for targeted drug delivery, minimizing off-target effects and optimizing therapeutic interventions. In regenerative medicine, exosomes play a crucial role in intercellular communication, facilitating tissue regeneration through the transmission of bioactive molecules. While acknowledging existing challenges in standardization and scalability, ongoing research efforts aim to refine methodologies and address regulatory considerations. In summary, this review underscores the transformative potential of exosomes in reshaping the landscape of medical interventions, with a particular emphasis on cancer, neurodegenerative diseases, and regenerative medicine.

Therapeutic Approaches and Potential Mechanisms of Small Extracellular Vesicles in Treating Vascular Dementia

Small extracellular vesicles (sEVs), including exosomes as a subtype, with a diameter typically less than 200 nm and originating from the endosomal system, are capable of transporting a diverse array of bioactive molecules, including proteins, nucleic acids, and lipids, thereby facilitating intercellular communication and modulating cellular functions. Vascular dementia (VaD) represents a form of cognitive impairment attributed to cerebrovascular disease, characterized by a complex and multifaceted pathophysiological mechanism. Currently, the therapeutic approach to VaD predominantly emphasizes symptom management, as no specific pharmacological treatment exists to cure the condition. Recent investigations have illuminated the significant role of sEVs in the pathogenesis of vascular dementia. This review seeks to provide a comprehensive analysis of the characteristics and functions of sEVs, with a particular focus on their involvement in vascular dementia and its underlying mechanisms. The objective is to advance the understanding of the interplays between sEVs and vascular dementia, thereby offering novel insights for future research and therapeutic strategies.

An anti-CD19-exosome delivery system navigates the blood-brain barrier for targeting of central nervous system lymphoma

BACKGROUND

High-dose methotrexate (HD-MTX) serves as the cornerstone of central nervous system lymphoma (CNSL) treatment, but its efficacy is limited due to low blood-brain barrier (BBB) penetration and adverse effects. This study is focused on an exosome-based drug delivery approach aimed at enhancing BBB permeability, thereby reducing the required dosage of methotrexate (MTX) while ensuring specific targeting of CNSL.

METHODS

Human adipose-derived mesenchymal stem cells (hAMSCs) were modified with a lentiviral vector encoding anti-CD19, incorporated into exosomes characterized by colloidal gold immunoelectron microscopy and Nano flow cytometry. MTX loaded into anti-CD19-Exos via co-incubation, assessed for loading and encapsulation efficiencies using HPLC. In vitro BBB model constructed using hCMEC/D3 and astrocytes to investigate BBB permeability. In vivo efficacy of anti-CD19-Exo-MTX evaluated in intracranial CNSL models using MRI. Biodistribution tracked with DiR-labeled exosomes, drug concentration in CSF measured by HPLC. LC-MS/MS identified and characterized exosomal proteins analyzed using GO Analysis. Neuroprotective effects of exosomal proteins assessed with TUNEL and Nissl staining on hippocampal neurons in CNSL models. Liver and kidney pathology, blood biochemical markers, and complete blood count evaluated exosomal protein effects on organ protection and MTX-induced myelosuppression.

RESULTS

We generated anti-CD19-Exo derived from hAMSCs. These adapted exosomes effectively encapsulated MTX, enhancing drug accessibility within lymphoma cells and sustained intracellular accumulation over an extended period. Notably, anti-CD19-Exo-MTX interacted with cerebrovascular endothelial cells and astrocytes of the BBB, leading to endocytosis and facilitating the transportation of MTX across the barrier. Anti-CD19-Exo-MTX outperformed free MTX in vitro, exhibiting a more potent lymphoma-suppressive effect (P < 0.05). In intracranial orthotopic CNSL models, anti-CD19-Exo-MTX exhibited a significantly reduced disease burden compared to both the MTX and Exo-MTX groups, along with prolonged overall survival (P < 0.05). CSF drug concentration analysis demonstrated enhanced stability and longer-lasting drug levels for anti-CD19-Exo-MTX. Anti-CD19-Exo-MTX exhibited precise CNSL targeting with no organ toxicity. Notably, our study highlighted the functional potential of reversal effect of hAMSCs-exosomes on MTX-induced neurotoxicity, hepatic and renal impairment, and myelosuppression.

CONCLUSIONS

We present anti-CD19-Exo-MTX as a promising exosome-based drug delivery platform that enhances BBB permeability and offers specific targeting for effective CNSL treatment with reduced adverse effects.

Liquid biopsies and exosomal ncRNA: Transforming pancreatic cancer diagnostics and therapeutics

Pancreatic cancer is a highly fatal malignancy due to poor early detection rate and resistance to conventional therapies. This review examines the potential for liquid biopsy as a transformative technology to identify diagnostic and therapeutic targets in pancreatic cancer. Specifically, we explore emerging biomarkers such as exosomal non-coding RNAs (ncRNAs), circulating tumor DNA (ctDNA), and circulating tumor cells (CTCs). Tumor-derived exosomes contain nucleic acid and protein that reflect the unique molecular landscape of the malignancy and can serve as an alternative diagnostic approach vs traditional biomarkers like CA19-9. Herein we highlight exosomal miRNAs, lncRNAs, and other ncRNAs alongside ctDNA and CTC-based strategies, evaluating their combined ability to improve early detection, disease monitoring and treatment response. Furthermore, the therapeutic implications of ncRNAs such as lncRNA UCA1 and miR-3960 in chemoresistance and progression are also discussed via suppression of EZH2 and PTEN/AKT pathways. Emerging therapeutic strategies that target the immune response, epithelial-mesenchymal transition (EMT) and drug resistance are explored. This review demonstrates a paradigm shift in pancreatic cancer management toward personalized, less invasive and more effective approaches.

Menopause mysteries: the exosome-inflammation connection

Extracellular vesicles, or exosomes, are produced by every type of cell and contain metabolites, proteins, lipids, and nucleic acids. Their role in health and disease is to influence different aspects of cell biology and to act as intermediaries between cells. Follicular fluid exosomes or extracellular vesicles (FF-EVs) secreted by ovarian granulosa cells are critical mediators of ovary growth and maturation. The movement and proteins of these exosomes are crucial in the regulation of cellular communication and the aging of cells, a process termed inflammaging. Menopause, a natural progression in the aging of females, is often accompanied by numerous negative symptoms and health issues. It can also act as a precursor to more severe health problems, including neurological, cardiovascular, and metabolic diseases, as well as gynecological cancers. Researchers have discovered pathways that reveal the diverse effects of exosome-driven cellular communication and oocyte development in the follicular fluid. It also explores the complex functions of FF exosomal proteins in the pathologies associated with menopause.

Extracellular Vesicles: Advanced Tools for Disease Diagnosis, Monitoring, and Therapies

Extracellular vesicles (EVs) are a heterogeneous group of membrane-encapsulated vesicles released by cells into the extracellular space. They play a crucial role in intercellular communication by transporting bioactive molecules such as proteins, lipids, and nucleic acids. EVs can be detected in body fluids, including blood plasma, urine, saliva, amniotic fluid, breast milk, and pleural ascites. The complexity and diversity of EVs require a robust and standardized approach. By adhering to standardized protocols and guidelines, researchers can ensure the consistency, purity, and reproducibility of isolated EVs, facilitating their use in diagnostics, therapies, and research. Exosomes and microvesicles represent an exciting frontier in modern medicine, with significant potential to transform the diagnosis and treatment of various diseases with an important role in personalized medicine and precision therapy. The primary objective of this review is to provide an updated analysis of the significance of EVs by highlighting their mechanisms of action and exploring their applications in the diagnosis and treatment of various diseases. Additionally, the review addresses the existing limitations and future potential of EVs, offering practical recommendations to resolve current challenges and enhance their viability for clinical use. This comprehensive approach aims to bridge the gap between EV research and its practical application in healthcare.

Exosomes and miRNAs in Cardiovascular Diseases and Transcatheter Pulmonary Valve Replacement: Advancements, Gaps and Perspectives

As an important carrier of intercellular information transmission, exosomes regulate the physiological and pathological state of local or distant cells by carrying a variety of signal molecules such as microRNAs (miRNAs). Current research indicates that exosomes and miRNAs can serve as biomarkers and therapeutic targets for a variety of cardiovascular diseases (CVDs). This narrative review summarizes the research progress of exosomes and their miRNAs in CVDs, particularly in pulmonary valve diseases (PVDs), and, for the first time, explores their potential associations with transcatheter pulmonary valve replacement (TPVR). Currently, miRNAs play a crucial role in determining the optimal timing for TPVR intervention, and they demonstrate broad application prospects in post-TPVR right ventricular (RV) remodeling, treatment, and prognosis monitoring. However, the association between exosomes and miRNAs and the development of PVDs, particularly pulmonary regurgitation, remains unclear. The molecular mechanisms of exosomes and miRNAs in PVDs and RV remodeling after TPVR have not been fully elucidated, and their application in postoperative treatment following TPVR is still in its infancy. Future research must focus on advancing fundamental studies, validating biomarkers, and enhancing clinical applications to achieve significant breakthroughs.

The Role of Cardiac Troponin and Other Emerging Biomarkers Among Athletes and Beyond: Underlying Mechanisms, Differential Diagnosis, and Guide for Interpretation

Cardiovascular (CV) disease remains the leading cause of morbidity and mortality worldwide, highlighting the necessity of understanding its underlying molecular and pathophysiological pathways. Conversely, physical activity (PA) and exercise are key strategies in reducing CV event risks. Detecting latent CV conditions in apparently healthy individuals, such as athletes, presents a unique challenge. The early identification and treatment of CV disorders are vital for long-term health and patient survival. Cardiac troponin is currently the most commonly used biomarker for assessing CV changes in both athletes and the general population. However, there remains considerable debate surrounding the mechanisms underlying exercise-induced troponin elevations and its release in non-ischemic contexts. Thus, there is a pressing need to identify and implement more sensitive and specific biomarkers for CV disorders in clinical practice. Indeed, research continues to explore reliable biomarkers for evaluating the health of athletes and the effectiveness of physical exercise. It is essential to analyze current evidence on troponin release in non-ischemic conditions, post-strenuous exercise, and the complex biological pathways that influence its detection. Furthermore, this study summarizes current research on cytokines and exosomes, including their physiological roles and their relevance in various CV conditions, especially in athletes. In addition, this paper gives special attention to underlying mechanisms, potential biomarkers, and future perspectives.

Human studies of the efficacy and safety of stem cells in the treatment of diabetic peripheral neuropathy: a systematic review and meta-analysis

OBJECTIVE

To assess the efficacy and safety of stem cell therapy in human studies for diabetic peripheral neuropathy (DPN).

METHODS

A comprehensive literature review was performed across multiple databases, including Ovid MEDLINE ALL, Embase via Ovid SP, Scopus, Web of Science Core Collection, and Cochrane CENTRAL, up to January 31, 2024. Keywords and controlled vocabularies related to diabetic neuropathy and stem cell therapy were used. Inclusion criteria encompassed all controlled trials examining stem cell therapy for DPN, excluding animal or in vitro studies, review papers, conference abstracts, and editor letters. Data extraction and risk of bias assessment were independently performed by multiple reviewers using standardized tools.

RESULTS

Out of 5431 initial entries, seven were included. Stem cell therapies included bone marrow-derived mononuclear cells and umbilical cord-derived mesenchymal stem cells, administered mainly via intramuscular transplantation. Meta-analysis indicated significant improvements in motor nerve conduction velocity (weighted mean differences (WMD): 2.2, 95% CI 1.6-2.8) and sensory nerve conduction velocity (WMD: 1.9, 95% CI 1.1-2.6). Vibration perception threshold and Toronto Clinical Scoring System scores decreased significantly (WMD: - 2.9, 95% CI - 4.0, - 1.8, and WMD: - 3.6, 95% CI - 5.0, - 2.2, respectively). Sensitivity analysis and subgroup analysis confirmed the robustness and specificity of these findings. The complications were pain and swelling at the injection sites, which disappeared in a few days.

CONCLUSION

Stem cell therapy shows significant promise in improving clinical outcomes for DPN, with evident benefits in nerve conduction and sensory parameters. Further research is needed to consolidate these findings and optimize therapeutic protocols.

Engineering Approaches for Exosome Cargo Loading and Targeted Delivery: Biological versus Chemical Perspectives

Exosomes are nanoscale membrane bound vesicles secreted by almost all types of cells. Their unique attributes, such as minimal immunogenicity and compatibility with biological systems, make them novel carriers for drug delivery. These native exosomes harbor proteins, nucleic acids, small molecule compounds, and fluorogenic agents. Moreover, through a combination of chemical and bioengineering methodologies, exosomes are tailored to transport precise therapeutic payloads to designated cells or tissues. In this review, we summarize the strategies for exosome modification and drug loading modalities in engineered exosomes. In addition, we provide an overview of the advances in the use of engineered exosomes for targeted drug delivery. Lastly, we discuss the merits and limitations of chemically engineered versus bioengineered exosome-mediated target therapies. These insights offer additional options for refining engineered exosomes in pharmaceutical development and hold promise for expediting the successful translation of engineered exosomes from the bench to the bedside.

Therapeutic combinations of exosomes alongside cancer stem cells (CSCs) and of CSC-derived exosomes (CSCEXs) in cancer therapy

Exosomes which are membrane vesicles released by cells have gained significant interest in the field of cancer therapy as a novel means of intercellular communication. Their role in immune activation and their pathophysiological functions in cancer therapy have been recognized. Exosomes carry diverse bioactive components including proteins, mRNA, microRNAs, and bioactive lipids. These molecules have therapeutic potential in promoting tissue regeneration, supporting stem cell activity, preventing cell death, modulating immune responses, and promoting the growth of new blood vessels. However, the precise roles of exosomes derived from mesenchymal stem cells (MSCs) in the treatment of various cancers are still not fully understood. Consequently, cancer stem cells (CSCs) can self-renew and differentiate into various cell types. Understanding the mechanisms that sustain their persistence is crucial for developing effective therapies. Exosomes have recently gained interest as vehicles for intercellular communication between CSCs and non-CSCs, influencing cancer progression and the microenvironment. Research is ongoing on the utilization of exosomes derived from cancer stem cells (CSC-Exosome) for cancer treatment. The composition of extracellular vesicles is influenced by the specific type and condition of the cells from which they are secreted. Circulating exosomes contain stable RNA molecules such as mRNAs, microRNAs, and long non-coding RNAs (lncRNAs). In this review, we will explore the significance of exosomes and their diverse cellular combinations in the context of cancer therapy.

Unveiling the promise: Exosomes as game-changers in anti-infective therapy

Extracellular vesicles (EVs)-based intercellular communication (through exosomes, microvesicles, and apoptotic bodies) is conserved across all kingdoms of life. In recent years, exosomes have gained much attention for targeted pharmaceutical administration due to their unique features, nanoscale size, and capacity to significantly contribute to cellular communication. As drug delivery vehicles, exosomes have several advantages over alternative nanoparticulate drug delivery technologies. A key advantage lies in their comparable makeup to the body's cells, which makes them non-immunogenic. However, exosomes vesicles face several challenges, including a lack of an effective and standard production technique, decreased drug loading capacity, limited characterization techniques, and underdeveloped isolation and purification procedures. Exosomes are well known for their long-term safety and natural ability to transport intercellular nucleic acids and medicinal compounds across the blood-brain-barrier (BBB). Therefore, in addition to revealing new insights into exosomes' distinctiveness, the growing availability of new analytical tools may drive the development of next-generation synthetic systems. Herein, light is shed on exosomes as drug delivery vehicles in anti-infective therapy by reviewing the literature on primary articles published between 2002 and 2023. Additionally, the benefits and limitations of employing exosomes as vehicles for therapeutic drug delivery are also discussed.

Enhancing Cartilage Repair: Surgical Approaches, Orthobiologics, and the Promise of Exosomes

Treating cartilage damage is challenging as its ability for self-regeneration is limited. Left untreated, it can progress to osteoarthritis (OA), a joint disorder characterized by the deterioration of articular cartilage and other joint tissues. Surgical options, such as microfracture and cell/tissue transplantation, have shown promise as techniques to harness the body's endogenous regenerative capabilities to promote cartilage repair. Nonetheless, these techniques have been scrutinized due to reported inconsistencies in long-term outcomes and the tendency for the defects to regenerate as fibrocartilage instead of the smooth hyaline cartilage native to joint surfaces. Orthobiologics are medical therapies that utilize biologically derived substances to augment musculoskeletal healing. These treatments are rising in popularity because of their potential to enhance surgical standards of care. More recent developments in orthobiologics have focused on the role of exosomes in articular cartilage repair. Exosomes are nano-sized extracellular vesicles containing cargo such as proteins, lipids, and nucleic acids, and are known to facilitate intercellular communication, though their regenerative potential still needs to be fully understood. This review aims to demonstrate the advancements in cartilage regeneration, highlight surgical and biological treatment options, and discuss the recent strides in understanding the precise mechanisms of action involved.

Exosomal misfolded proteins released by cancer stem cells: dual functions in balancing protein homeostasis and orchestrating tumor progression

Cancer stem cells (CSCs), the master regulators of tumor heterogeneity and progression, exert profound influence on cancer metastasis, via various secretory vesicles. Emerging from CSCs, the exosomes serve as pivotal mediators of intercellular communication within the tumor microenvironment, modulating invasion, angiogenesis, and immune responses. Moreover, CSC-derived exosomes play a central role in sculpting a dynamic landscape, contributing to the malignant phenotype. Amidst several exosomal cargoes, misfolded proteins have recently gained attention for their dual functions in maintaining protein homeostasis and promoting tumor progression. Disrupting these communication pathways could potentially prevent the maintenance and expansion of CSCs, overcome treatment resistance, and inhibit the supportive environment created by the tumor microenvironment, thereby improving the effectiveness of cancer therapies and reducing the risk of tumor recurrence and metastasis. Additionally, exosomes have also shown potential therapeutic applications, such as in drug delivery or as biomarkers for cancer diagnosis and prognosis. Therefore, comprehending the biology of exosomes derived from CSCs is a multifaceted area of research with implications in both basic sciences and clinical applications. This review explores the intricate interplay between exosomal misfolded proteins released by CSCs, the potent contributor in tumor heterogeneity, and their impact on cellular processes, shedding light on their role in cancer progression.

The role of the hematopoietic stem/progenitor cells-derived extracellular vesicles in hematopoiesis

Hematopoietic stem cells (HSCs) are tightly regulated by specific microenvironments called niches to produce an appropriate number of mature blood cell types. Self-renewal and differentiation are two hallmarks of hematopoietic stem and progenitor cells, and their balance is critical for proper functioning of blood and immune cells throughout life. In addition to cell-intrinsic regulation, extrinsic cues within the bone marrow niche and systemic factors also affect the fate of HSCs. Despite this, many paracrine and endocrine factors that influence the function of hematopoietic cells remain unknown. In hematological malignancies, malignant cells remodel their niche into a permissive environment to enhance the survival of leukemic cells. These events are accompanied by loss of normal hematopoiesis. It is well known that extracellular vehicles (EVs) mediate intracellular interactions under physiological and pathological conditions. In other words, EVs transfer biological information to surrounding cells and contribute not only to physiological functions but also to the pathogenesis of some diseases, such as cancers. Therefore, a better understanding of cell-to-cell interactions may lead to identification of potential therapeutic targets. Recent reports have suggested that EVs are evolutionarily conserved constitutive mediators that regulate hematopoiesis. Here, we focus on the emerging roles of EVs in normal and pathological conditions, particularly in hematological malignancies. Owing to the high abundance of EVs in biological fluids, their potential use as biomarkers and therapeutic tools is discussed.

Exosomes in Osteoarthritis: A Review on Their Isolation Techniques and Therapeutic Potential

Background

Exosomes are the smallest extracellular vesicles (30-150 nm) secreted by all cell types, including synovial fluid. However, because biological fluids are complex, heterogeneous, and contain contaminants, their isolation is difficult and time-consuming. Furthermore, the pathophysiology of osteoarthritis (OA) involves exosomes carrying complex components that cause macrophages to release chemokines and proinflammatory cytokines. This narrative review aims to provide in-depth insights into exosome biology, isolation techniques, role in OA pathophysiology, and potential role in future OA therapeutics.

Methods

A literature search was conducted using PubMed, Scopus, and Web of Science databases for studies involving exosomes in the osteoarthritis using keywords "Exosomes" and "Osteoarthritis". Relevant articles in the last 15 years involving both human and animal models were included. Studies involving exosomes in other inflammatory diseases were excluded.

Results

Despite some progress, conventional techniques for isolating exosomes remain laborious and difficult, requiring intricate and time-consuming procedures across various body fluids and sample origins. Moreover, exosomes are involved in various physiological processes associated with OA, like cartilage calcification, degradation of osteoarthritic joints, and inflammation.

Conclusion

The process of achieving standardization, integration, and high throughput of exosome isolation equipment is challenging and time-consuming. The integration of various methodologies can be employed to effectively address specific issues by leveraging their complementary benefits. Exosomes have the potential to effectively repair damaged cartilage OA, reduce inflammation, and maintain a balance between the formation and breakdown of cartilage matrix, therefore showing promise as a therapeutic option for OA.

Mitigation of Oxidative Stress in Idiopathic Pulmonary Fibrosis Through Exosome-Mediated Therapies

Idiopathic pulmonary fibrosis (IPF) poses a formidable clinical challenge, characterized by the thickening of alveolar septa and the onset of pulmonary fibrosis. The pronounced activation of oxidative stress emerges as a pivotal hallmark of inflammation. Traditional application of exogenous antioxidants proves inadequate in addressing oxidative stress, necessitating exploration into strategies to augment their antioxidant efficacy. Exosomes, nano-sized extracellular vesicles harboring a diverse array of bioactive factors, present as promising carriers with the potential to meet this challenge. Recent attention has been directed towards the clinical applications of exosomes in IPF, fueling the impetus for this comprehensive review. We have compiled fresh insights into the role of exosomes in modulating oxidative stress in IPF and delved into their potential as carriers for regulating endogenous reactive oxygen species generation. This review endeavors to bridge the divide between exosome research and IPF, traversing from bedside to bench. Through the synthesis of recent findings, we propose exosomes as a novel and promising strategy for improving the outcomes of IPF therapy.

Mesenchymal stem cell-derived exosomes for management of prostate cancer: An updated view

Prostate cancer represents the second most prevalent form of cancer found in males, and stands as the fifth primary contributor to cancer-induced mortality on a global scale. Research has shown that transplanted mesenchymal stem cells (MSCs) can migrate by homing to tumor sites in the body. In prostate cancer, researchers have explored the fact that MSC-based therapies (including genetically modified delivery vehicles or vectors) and MSC-derived exosomes are emerging as attractive options to improve the efficacy and safety of traditional cancer therapies. In addition, researchers have reported new insights into the application of extracellular vesicle (EV)-MSC therapy as a novel treatment option that could provide a more effective and targeted approach to prostate cancer treatment. Moreover, the new generation of exosomes, which contain biologically functional molecules as signal transducers between cells, can simultaneously deliver different therapeutic agents and induce an anti-tumor phenotype in immune cells and their recruitment to the tumor site. The results of the current research on the use of MSCs in the treatment of prostate cancer may be helpful to researchers and clinicians working in this field. Nevertheless, it is crucial to emphasize that although dual-role MSCs show promise as a therapeutic modality for managing prostate cancer, further investigation is imperative to comprehensively grasp their safety and effectiveness. Ongoing clinical trials are being conducted to assess the viability of MSCs in the management of prostate cancer. The results of these trials will help determine the viability of this approach. Based on the current literature, engineered MSCs-EV offer great potential for application in targeted tumor therapy.

Plasma and synovial fluid extracellular vesicles display altered microRNA profiles in horses with naturally occurring post-traumatic osteoarthritis: an exploratory study

OBJECTIVE

The objective of this study was to characterize extracellular vesicles (EVs) in plasma and synovial fluid obtained from horses with and without naturally occurring post-traumatic osteoarthritis (PTOA).

ANIMALS

EVs were isolated from plasma and synovial fluid from horses with (n = 6) and without (n = 6) PTOA.

METHODS

Plasma and synovial fluid EVs were characterized with respect to quantity, size, and surface markers. Small RNA sequencing was performed, and differentially expressed microRNAs (miRNAs) underwent bioinformatic analysis to identify putative targets and to explore potential associations with specific biological processes.

RESULTS

Plasma and synovial fluid samples from horses with PTOA had a significantly higher proportion of exosomes and a lower proportion of microvesicles compared to horses without PTOA. Small RNA sequencing revealed several differentially expressed miRNAs, including miR-144, miR-219-3p, and miR-199a-3l in plasma and miR-199a-3p, miR-214, and miR-9094 in synovial fluid EVs. Bioinformatics analysis of the differentially expressed miRNAs highlighted their potential role in fibrosis, differentiation of chondrocytes, apoptosis, and inflammation pathways in PTOA.

CLINICAL RELEVANCE

We have identified dynamic molecular changes in the small noncoding signatures of plasma and synovial fluid EVs in horses with naturally occurring PTOA. These findings could serve to identify promising biomarkers in the pathogenesis of PTOA, to facilitate the development of targeted therapies, and to aid in establishing appropriate translational models of PTOA.

Expression profiling & functional characterization of candidate miRNAs in serum exosomes among Indians with & without HIV-tuberculosis coinfection

Background & objectives Despite the evidence of population differences in miRNA expression, limited information is available about the expression profile of miRNAs in Indian tuberculosis (TB) patients. The present study aimed to investigate the expression profile of candidate serum exosomal microRNAs in Indian patients with and without HIV-TB coinfection. Methods The pool samples of serum exosomes of study participants (HIV-TB coinfection, extra-pulmonary TB, HIV mono-infection, pulmonary TB) and healthy humans were processed for the isolation of total RNA followed by miRNA analysis using miRCURY LNA human focus PCR panel by real-time PCR. The significantly altered miRNAs were identified using differential expression analysis. The target genes prediction and potential functional analysis of exclusively differentially expressed miRNAs were performed using bioinformatics tools. Results The expression profile of 57, 58, 49 and 11 miRNAs was significantly altered in exosome samples of HIV-TB coinfected, extra-pulmonary TB, HIV mono-infected and pulmonary TB patients compared to healthy controls, respectively. The set of three (hsa-let-7i-5p, hsa-miR-24-3p, hsa-miR-92a-3p), three (hsa-miR-20a-5p, hsa-let-7e-5p, hsa-miR-26a-5p) and four (hsa-miR-21-5p, hsa-miR-19a-3p, hsa-miR-19b-3p, hsa-miR-146a-5p) miRNAs were exclusively significantly differentially expressed in study participants with HIV-TB coinfection, extra-pulmonary TB and pulmonary TB, respectively. Most of the target genes of exclusively differentially expressed miRNAs were enriched in pathways in cancer, MAPK signalling pathway and Ras signalling pathway. Interpretation & conclusions The present study demonstrates a distinct expression profile of miRNAs in serum exosomes of the study participants and identified crucial miRNAs which may have a significant impact on the biomarker analysis and pathogenesis of TB in Indian patients.

Increasing the sensitivity and accuracy of detecting exosomes as biomarkers for cancer monitoring using optical nanobiosensors

The advancement of nanoscience and material design in recent times has facilitated the creation of point-of-care devices for cancer diagnosis and biomolecule sensing. Exosomes (EXOs) facilitate the transfer of bioactive molecules between cancer cells and diverse cells in the local and distant microenvironments, thereby contributing to cancer progression and metastasis. Specifically, EXOs derived from cancer are likely to function as biomarkers for early cancer detection due to the genetic or signaling alterations they transport as payload within the cancer cells of origin. It has been verified that EXOs circulate steadily in bodily secretions and contain a variety of information that indicates the progression of the tumor. However, acquiring molecular information and interactions regarding EXOs has presented significant technical challenges due to their nanoscale nature and high heterogeneity. Colorimetry, surface plasmon resonance (SPR), fluorescence, and Raman scattering are examples of optical techniques utilized to quantify cancer exosomal biomarkers, including lipids, proteins, RNA, and DNA. Many optically active nanoparticles (NPs), predominantly carbon-based, inorganic, organic, and composite-based nanomaterials, have been employed in biosensing technology. The exceptional physical properties exhibited by nanomaterials, including carbon NPs, noble metal NPs, and magnetic NPs, have facilitated significant progress in the development of optical nanobiosensors intended for the detection of EXOs originating from tumors. Following a summary of the biogenesis, biological functions, and biomarker value of known EXOs, this article provides an update on the detection methodologies currently under investigation. In conclusion, we propose some potential enhancements to optical biosensors utilized in detecting EXO, utilizing various NP materials such as silicon NPs, graphene oxide (GO), metal NPs, and quantum dots (QDs).

Insight into the Functional Dynamics and Challenges of Exosomes in Pharmaceutical Innovation and Precision Medicine

Of all the numerous nanosized extracellular vesicles released by a cell, the endosomal-originated exosomes are increasingly recognized as potential therapeutics, owing to their inherent stability, low immunogenicity, and targeted delivery capabilities. This review critically evaluates the transformative potential of exosome-based modalities across pharmaceutical and precision medicine landscapes. Because of their precise targeted biomolecular cargo delivery, exosomes are posited as ideal candidates in drug delivery, enhancing regenerative medicine strategies, and advancing diagnostic technologies. Despite the significant market growth projections of exosome therapy, its utilization is encumbered by substantial scientific and regulatory challenges. These include the lack of universally accepted protocols for exosome isolation and the complexities associated with navigating the regulatory environment, particularly the guidelines set forth by the U.S. Food and Drug Administration (FDA). This review presents a comprehensive overview of current research trajectories aimed at addressing these impediments and discusses prospective advancements that could substantiate the clinical translation of exosomal therapies. By providing a comprehensive analysis of both the capabilities and hurdles inherent to exosome therapeutic applications, this article aims to inform and direct future research paradigms, thereby fostering the integration of exosomal systems into mainstream clinical practice.

Fingerprinting Breast Milk; insights into Milk Exosomics

Breast milk, often referred to as "liquid gold," is a complex biofluid that provides essential nutrients, immune factors, and developmental cues for newborns. Recent advancements in the field of exosome research have shed light on the critical role of exosomes in breast milk. Exosomes are nanosized vesicles that carry bioactive molecules, including proteins, lipids, nucleic acids, and miRNAs. These tiny messengers play a vital role in intercellular communication and are now being recognized as key players in infant health and development. This paper explores the emerging field of milk exosomics, emphasizing the potential of exosome fingerprinting to uncover valuable insights into the composition and function of breast milk. By deciphering the exosomal cargo, we can gain a deeper understanding of how breast milk influences neonatal health and may even pave the way for personalized nutrition strategies.

Environmental pollutants and exosomes: A new paradigm in environmental health and disease

This study investigates the intricate interplay between environmental pollutants and exosomes, shedding light on a novel paradigm in environmental health and disease. Cellular stress, induced by environmental toxicants or disease, significantly impacts the production and composition of exosomes, crucial mediators of intercellular communication. The heat shock response (HSR) and unfolded protein response (UPR) pathways, activated during cellular stress, profoundly influence exosome generation, cargo sorting, and function, shaping intercellular communication and stress responses. Environmental pollutants, particularly lipophilic ones, directly interact with exosome lipid bilayers, potentially affecting membrane stability, release, and cellular uptake. The study reveals that exposure to environmental contaminants induces significant changes in exosomal proteins, miRNAs, and lipids, impacting cellular function and health. Understanding the impact of environmental pollutants on exosomal cargo holds promise for biomarkers of exposure, enabling non-invasive sample collection and real-time insights into ongoing cellular responses. This research explores the potential of exosomal biomarkers for early detection of health effects, assessing treatment efficacy, and population-wide screening. Overcoming challenges requires advanced isolation techniques, standardized protocols, and machine learning for data analysis. Integration with omics technologies enhances comprehensive molecular analysis, offering a holistic understanding of the complex regulatory network influenced by environmental pollutants. The study underscores the capability of exosomes in circulation as promising biomarkers for assessing environmental exposure and systemic health effects, contributing to advancements in environmental health research and disease prevention.

Exosome-like Systems: From Therapies to Vaccination for Cancer Treatment and Prevention-Exploring the State of the Art

Cancer remains one of the main causes of death in the world due to its increasing incidence and treatment difficulties. Although significant progress has been made in this field, innovative approaches are needed to reduce tumor incidence, progression, and spread. In particular, the development of cancer vaccines is currently ongoing as both a preventive and therapeutic strategy. This concept is not new, but few vaccines have been approved in oncology. Antigen-based vaccination emerges as a promising strategy, leveraging specific tumor antigens to activate the immune system response. However, challenges persist in finding suitable delivery systems and antigen preparation methods. Exosomes (EXs) are highly heterogeneous bilayer vesicles that carry several molecule types in the extracellular space. The peculiarity is that they may be released from different cells and may be able to induce direct or indirect stimulation of the immune system. In particular, EX-based vaccines may cause an anti-tumor immune attack or produce memory cells recognizing cancer antigens and inhibiting disease development. This review delves into EX composition, biogenesis, and immune-modulating properties, exploring their role as a tool for prevention and therapy in solid tumors. Finally, we describe future research directions to optimize vaccine efficacy and realize the full potential of EX-based cancer immunotherapy.

Extracellular vesicles in cancer therapy: Roles, potential application, and challenges

Extracellular vesicles (EVs) have emerged as a novel cell-free strategy for the treatment of many diseases including cancer as they play important roles in cancer development and progression. Considering their natural capacity to facilitate cell-to-cell communication as well as their high physiochemical stability and biocompatibility, EVs serve as superior delivery systems for a wide range of therapeutic agents, including medicines, nanomaterials, nucleic acids, and proteins. Therefore, EVs-based cancer therapy is of greater interest to researchers. Mounting studies indicate that EVs can be improved in efficiency, specificity, and safety for cancer therapy. However, their heterogeneity of physicochemical properties and functions is not fully understood, hindering the achievement of bioactive EVs with high yield and purity. Herein, we paid more attention to the EVs applications and their significance in cancer therapy.

Unveiling the Role of Exosomes in the Pathophysiology of Sepsis: Insights into Organ Dysfunction and Potential Biomarkers

Extracellular vesicles (EVs) are tools for intercellular communication, mediating molecular transport processes. Emerging studies have revealed that EVs are significantly involved in immune processes, including sepsis. Sepsis, a dysregulated immune response to infection, triggers systemic inflammation and multi-organ dysfunction, posing a life-threatening condition. Although extensive research has been conducted on animals, the complex inflammatory mechanisms that cause sepsis-induced organ failure in humans are still not fully understood. Recent studies have focused on secreted exosomes, which are small extracellular vesicles from various body cells, and have shed light on their involvement in the pathophysiology of sepsis. During sepsis, exosomes undergo changes in content, concentration, and function, which significantly affect the metabolism of endothelia, cardiovascular functions, and coagulation. Investigating the role of exosome content in the pathogenesis of sepsis shows promise for understanding the molecular basis of human sepsis. This review explores the contributions of activated immune cells and diverse body cells' secreted exosomes to vital organ dysfunction in sepsis, providing insights into potential molecular biomarkers for predicting organ failure in septic shock.

The Landscape of Exosomes Biogenesis to Clinical Applications

Exosomes are extracellular vesicles that originate from various cells and mediate intercellular communication, altering the behavior or fate of recipient cells. They carry diverse macromolecules, such as lipids, proteins, carbohydrates, and nucleic acids. Environmental stressors can change the exosomal contents of many cells, making them useful for diagnosing many chronic disorders, especially neurodegenerative, cardiovascular, cancerous, and diabetic diseases. Moreover, exosomes can be engineered as therapeutic agents to modulate disease processes. State-of-art techniques are employed to separate exosomes including ultracentrifugation, size-exclusion chromatography and immunoaffinity. However, modern technologies such as aqueous two-phase system as well as microfluidics are gaining attention in the recent years. The article highlighted the composition, biogenesis, and implications of exosomes, as well as the standard and novel methods for isolating them and applying them as biomarkers and therapeutic cargo carriers.

Engineered exosomes and composite biomaterials for tissue regeneration

Exosomes, which are small vesicles enclosed by a lipid bilayer and released by many cell types, are widely dispersed and have garnered increased attention in the field of regenerative medicine due to their ability to serve as indicators of diseases and agents with therapeutic potential. Exosomes play a crucial role in mediating intercellular communication through the transfer of many biomolecules, including proteins, lipids, RNA, and other molecular constituents, between cells. The targeted transport of proteins and nucleic acids to specific cells has the potential to enhance or impair specific biological functions. Exosomes have many applications, and they can be used alone or in combination with other therapeutic approaches. The examination of the unique attributes and many functions of these factors has emerged as a prominent field of study in the realm of biomedical research. This manuscript summarizes the origins and properties of exosomes, including their structural, biological, physical, and chemical aspects. This paper offers a complete examination of recent progress in tissue repair and regenerative medicine, emphasizing the possible implications of these methods in forthcoming tissue regeneration attempts.

Dendritic cell-derived exosomes (Dex): Underlying the role of exosomes derived from diverse DC subtypes in cancer pathogenesis

Exosomes are nanometric membrane vesicles of late endosomal origin that are released by most, if not all, cell types as a sophisticated means of intercellular communication. They play an essential role in the movement of materials and information between cells, transport a variety of proteins, lipids, RNA, and other vital data, and over time, they become an essential part of the drug delivery system and a marker for the early detection of many diseases. Dendritic cells have generated interest in cancer immunotherapy due to their ability to initiate and modify effective immune responses. Apart from their cytokine release and direct interactions with other cell types, DCs also emit nanovesicles, such as exosomes, that contribute to their overall activity. Numerous studies have demonstrated exosomes to mediate and regulate immune responses against cancers. Dendritic cell-derived exosomes (DCs) have attracted a lot of attention as immunotherapeutic anti-cancer treatments since it was found that they contain functional MHC-peptide complexes along with a variety of other immune-stimulating components that together enable immune cell-dependent tumor rejection. By enhancing tumor and immunosuppressive immune cells or changing a pro-inflammatory milieu to inhibit tumor advancement, exosomes generated from dendritic cells can initiate and support tumor growth. This study reviewed the immunogenicity of dendritic cell-derived exosomes and strategies for expanding their immunogenic potential as novel and effective anti-cancer therapies.

Exosome-mediated regulation of inflammatory pathway during respiratory viral disease

Viruses have developed many mechanisms by which they can stimulate or inhibit inflammation and cause various diseases, including viral respiratory diseases that kill many people every year. One of the mechanisms that viruses use to induce or inhibit inflammation is exosomes. Exosomes are small membrane nanovesicles (30-150 nm) released from cells that contain proteins, DNA, and coding and non-coding RNA species. They are a group of extracellular vesicles that cells can take up to produce and mediate communication. Intercellular effect exosomes can deliver a broad confine of biological molecules, containing nucleic acids, proteins, and lipids, to the target cell, where they can convey therapeutic or pathogenic consequences through the modulation of inflammation and immune processes. Recent research has shown that exosomes can deliver entire virus genomes or virions to distant target cells, then the delivered viruses can escape the immune system and infect cells. Adenoviruses, orthomyxoviruses, paramyxoviruses, respiratory syncytial viruses, picornaviruses, coronaviruses, and rhinoviruses are mostly related to respiratory diseases. In this article, we will first discuss the current knowledge of exosomes. We will learn about the relationship between exosomes and viral infections, and We mention the inflammations caused by viruses in the airways, the role of exosomes in them, and finally, we examine the relationship between the viruses as mentioned earlier, and the regulation of inflammatory pathways that play a role in causing the disease.

Exosomes in neuron-glia communication: A review on neurodegeneration

Introduction

Exosomes, a subset of extracellular vesicles (EVs), are crucial for intercellular communication in various contexts. Despite their small size, they carry diverse cargo, including RNA, proteins, and lipids. Internalization by recipient cells raises concerns about potential disruptions to cellular functions. Notably, the ability of exosomes to traverse the blood-brain barrier (BBB) has significant implications.

Methods

To conduct a thorough investigation into the existing academic literature on exosomes within the framework of neuron-glia communication, a comprehensive search strategy was implemented across the PubMed, Google Scholar, and Science Direct databases. Multiple iterations of the keywords "exosome," "neuron-glia communication," and "neurological disorders" were employed to systematically identify relevant publications. Furthermore, an exploration of the Clinicaltrials.gov database was undertaken to identify clinical trials related to cellular signaling, utilizing analogous terminology.

Results

Although the immediate practical applications of exosomes are somewhat limited, their potential as carriers of pathogenic attributes offers promising opportunities for the development of precisely targeted therapeutic strategies for neurological disorders. This review presents a comprehensive overview of contemporary insights into the pivotal roles played by exosomes as agents mediating communication between neurons and glial cells within the central nervous system (CNS).

Conclusion

By delving into the intricate dynamics of exosomal communication in the CNS, this review contributes to a deeper understanding of the roles of exosomes in both physiological and pathological processes, thereby paving the way for potential therapeutic advancements in the field of neurological disorders.

Bone marrow mesenchymal stem cell‑derived exosomes: A novel therapeutic agent for tendon‑bone healing (Review)

In sports medicine, injuries related to the insertion of tendons into bones, including rotator cuff injuries, anterior cruciate ligament injuries and Achilles tendon ruptures, are commonly observed. However, traditional therapies have proven to be insufficient in achieving satisfactory outcomes due to the intricate anatomical structure associated with these injuries. Adult bone marrow mesenchymal stem cells possess self‑renewal and multi‑directional differentiation potential and can generate various mesenchymal tissues to aid in the recovery of bone, cartilage, adipose tissue and bone marrow hematopoietic tissue. In addition, extracellular vesicles derived from bone marrow mesenchymal stem cells known as exosomes, contain lipids, proteins and nucleic acids that govern the tissue microenvironment, facilitate tissue repair and perform various biological functions. Studies have demonstrated that bone marrow mesenchymal stem cell‑derived exosomes can function as natural nanocapsules for drug delivery and can enhance tendon‑bone healing strength. The present review discusses the latest research results on the role of exosomes released by bone marrow mesenchymal stem cells in tendon‑bone healing and provides valuable information for implementing these techniques in regenerative medicine and sports health.

Biological, pathological, and multifaceted therapeutic functions of exosomes to target cancer

Exosomes, small tiny vesicle contains a large number of intracellular particles that employ to cause various diseases and prevent several pathological events as well in the human body. It is considered a "double-edged sword", and depending on its biological source, the action of exosomes varies under physiological conditions. Also, the isolation and characterization of the exosomes should be performed accurately and the methodology also will vary depending on the exosome source. Moreover, the uptake of exosomes from the recipients' cells is a vital and initial step for all the physiological actions. There are different mechanisms present in the exosomes' cellular uptake to deliver their cargo to acceptor cells. Once the exosomal uptake takes place, it releases the intracellular particles that leads to activate the physiological response. Even though exosomes have lavish functions, there are some challenges associated with every step of their preparation to bring potential therapeutic efficacy. So, overcoming the pitfalls would give a desired quantity of exosomes with high purity.

Exosomes multifunctional roles in HIV-1: insight into the immune regulation, vaccine development and current progress in delivery system

Human Immunodeficiency Virus (HIV-1) is known to establish a persistent latent infection. The use of combination antiretroviral therapy (cART) can effectively reduce the viral load, but the treatment can be costly and may lead to the development of drug resistance and life-shortening side effects. It is important to develop an ideal and safer in vivo target therapy that will effectively block viral replication and expression in the body. Exosomes have recently emerged as a promising drug delivery vehicle due to their low immunogenicity, nanoscale size (30-150nm), high biocompatibility, and stability in the targeted area. Exosomes, which are genetically produced by different types of cells such as dendritic cells, neurons, T and B cells, epithelial cells, tumor cells, and mast cells, are designed for efficient delivery to targeted cells. In this article, we review and highlight recent developments in the strategy and application of exosome-based HIV-1 vaccines. We also discuss the use of exosome-based antigen delivery systems in vaccine development. HIV-1 antigen can be loaded into exosomes, and this modified cargo can be delivered to target cells or tissues through different loading approaches. This review also discusses the immunological prospects of exosomes and their role as biomarkers in disease progression. However, there are significant administrative and technological obstacles that need to be overcome to fully harness the potential of exosome drug delivery systems.

Discerning the Prospects of miRNAs as a Multi-Target Therapeutic and Diagnostic for Alzheimer's Disease

Although over the last few decades, numerous attempts have been made to halt Alzheimer's disease (AD) progression and mitigate its symptoms, only a few have been proven beneficial. Most medications available, still only cater to the symptoms of the disease rather than fixing the cause at the root level. A novel approach involving the use of miRNAs, which work on the principle of gene silencing, is being explored by scientists. Naturally present miRNAs in the biological system help to regulate various genes than may be implicated in AD-like BACE-1 and APP. One miRNA thus, holds the power to keep a check on several genes, conferring it the ability to be used as a multi-target therapeutic. With aging and the onset of diseased pathology, dysregulation of these miRNAs is observed. This flawed miRNA expression is responsible for the unusual buildup of amyloid proteins, fibrillation of tau proteins in the brain, neuronal death and other hallmarks leading to AD. The use of miRNA mimics and miRNA inhibitors provides an attractive perspective for fixing the upregulation and downregulation of miRNAs that led to abnormal cellular activities. Furthermore, the detection of miRNAs in the CSF and serum of diseased patients might be considered an earlier biomarker for the disease. While most of the therapies designed around AD have not succeeded completely, the targeting of dysregulated miRNAs in AD patients might give a new direction to scholars to develop an effective treatment for Alzheimer's disease.

Biogenesis, Isolation, and Detection of Exosomes and Their Potential in Therapeutics and Diagnostics

The increasing research and rapid developments in the field of exosomes provide insights into their role and significance in human health. Exosomes derived from various sources, such as mesenchymal stem cells, cardiac cells, and tumor cells, to name a few, can be potential therapeutic agents for the treatment of diseases and could also serve as biomarkers for the early detection of diseases. Cellular components of exosomes, several proteins, lipids, and miRNAs hold promise as novel biomarkers for the detection of various diseases. The structure of exosomes enables them as drug delivery vehicles. Since exosomes exhibit potential therapeutic applications, their efficient isolation from complex biological/clinical samples and precise real-time analysis becomes significant. With the advent of microfluidics, nano-biosensors are being designed to capture exosomes efficiently and rapidly. Herein, we have summarized the history, biogenesis, characteristics, functions, and applications of exosomes, along with the isolation, detection, and quantification techniques. The implications of surface modifications to enhance specificity have been outlined. The review also sheds light on the engineered nanoplatforms being developed for exosome detection and capture.

The Fatal Role of Enterohaemorrhagic Escherichia coli Shiga Toxin-associated Extracellular Vesicles in Host Cells

Enterohemorrhagic Escherichia coli (EHEC) is a specific subset of Shiga toxin-producing Escherichia coli (STEC) strains that are characterized by their ability to cause bloody diarrhea (hemorrhagic colitis) and potentially life-threatening, extraintestinal complications such as hemolytic uremic syndrome (HUS), which is associated with acute renal failure., contributing to severe clinical outcomes. The Shiga toxins (Stxs), produced by EHEC, are primary virulence factors. These potent cytotoxins are composed of one enzymatically active A subunit (StxA) and five receptor-binding B subunits (StxB). Although the toxins are primarily associated with cytotoxic effects, they also elicit other pathogenic consequences due to their induction of a number of biological processes, including apoptosis through ER-stress, pro-inflammatory responses, autophagy, and post-translational modification (PTM). Moreover, several studies have reported the association between Stxs and extracellular vesicles (EVs), including microvesicles and exosomes, demonstrating that Stx-containing EVs secreted by intoxicated macrophages are taken up by recipient cells, such as toxin-sensitive renal proximal tubular epithelial cells. This mechanism likely contributes to the spreading of Stxs within the host, and may exacerbate gastrointestinal illnesses and kidney dysfunction. In this review, we summarize recent findings relating to the host responses, in different types of cells in vitro and in animal models, mediated by Stxs-containing exosomes. Due to their unique properties, EVs have been explored as therapeutic agents, drug delivery systems, and diagnostic tools. Thus, potential therapeutic applications of EVs in EHEC Stxs-mediated pathogenesis are also briefly reviewed.

Plasma Exosomal microRNA Profile Reveals miRNA 148a-3p Downregulation in the Mucosal-Dominant Variant of Pemphigus Vulgaris

The mucosal-dominant variant of pemphigus vulgaris (MPV) is an autoimmune disease characterized by oral mucosal blistering and circulating pathogenic IgG antibodies against desmoglein 3 (Dsg3), resulting in life-threatening bullae and erosion formation. Recently, microRNAs (miRNAs) have emerged as promising players in the diagnosis and prognosis of several pathological states. For the first time, we have identified a different expression profile of miRNAs isolated from plasma-derived exosomes (P-EVs) of MPV patients positive for antibodies against Dsg3 (Dsg3-positive) compared to healthy controls. Moreover, a dysregulated miRNA profile was confirmed in MPV tissue biopsies. In particular, a strong downregulation of the miR-148a-3p expression level in P-EVs of MPV patients compared to healthy controls was demonstrated. Bioinformatics prediction analysis identifies metalloproteinase-7 (MMP7) as a potential miR-148a-3p target. An in vitro acantholysis model revealed that the miR-148a-3p expression level was dramatically downregulated after treatment with Dsg3 autoantibodies, with a concomitant increase in MMP7 expression. The increased expression of MMP7 leads to the disruption of intercellular and/or extracellular matrix adhesion in an in vitro cellular model of MPV, with subsequent cell dissociation. Overexpression of miR-148a-3p prevented cell dissociation and regressed MMP7 upregulation. Our findings suggest a pivotal role of P-EV cargo in regulating molecular mechanisms involved in MPV pathogenesis and indicate them as potential MPV therapeutic targets.

Exosomes in brain diseases: Pathogenesis and therapeutic targets

Exosomes are extracellular vesicles with diameters of about 100 nm that are naturally secreted by cells into body fluids. They are derived from endosomes and are wrapped in lipid membranes. Exosomes are involved in intracellular metabolism and intercellular communication. They contain nucleic acids, proteins, lipids, and metabolites from the cell microenvironment and cytoplasm. The contents of exosomes can reflect their cells' origin and allow the observation of tissue changes and cell states under disease conditions. Naturally derived exosomes have specific biomolecules that act as the "fingerprint" of the parent cells, and the contents changed under pathological conditions can be used as biomarkers for disease diagnosis. Exosomes have low immunogenicity, are small in size, and can cross the blood-brain barrier. These characteristics make exosomes unique as engineering carriers. They can incorporate therapeutic drugs and achieve targeted drug delivery. Exosomes as carriers for targeted disease therapy are still in their infancy, but exosome engineering provides a new perspective for cell-free disease therapy. This review discussed exosomes and their relationship with the occurrence and treatment of some neuropsychiatric diseases. In addition, future applications of exosomes in the diagnosis and treatment of neuropsychiatric disorders were evaluated in this review.

The emerging roles of long non-coding RNA in host immune response and intracellular bacterial infections

The long non-coding RNAs (lncRNAs) are evolutionarily conserved classes of non-coding regulatory transcripts of > 200 nucleotides in length. They modulate several transcriptional and post-transcriptional events in the organism. Depending on their cellular localization and interactions, they regulate chromatin function and assembly; and alter the stability and translation of cytoplasmic mRNAs. Although their proposed range of functionality remains controversial, there is increasing research evidence that lncRNAs play a regulatory role in the activation, differentiation and development of immune signaling cascades; microbiome development; and in diseases such as neuronal and cardiovascular disorders; cancer; and pathogenic infections. This review discusses the functional roles of different lncRNAs in regulation of host immune responses, signaling pathways during host-microbe interaction and infection caused by obligate intracellular bacterial pathogens. The study of lncRNAs is assuming significance as it could be exploited for development of alternative therapeutic strategies for the treatment of severe and chronic pathogenic infections caused by Mycobacterium, Chlamydia and Rickettsia infections, as well as commensal colonization. Finally, this review summarizes the translational potential of lncRNA research in development of diagnostic and prognostic tools for human diseases.

Study the association of microRNA polymorphisms (miR-146a, miR-4513) with the risk of coronary heart diseases in Egyptian population

Coronary heart disease (CHD) is the most prevalent cause of cardiovascular mortality in the world. It is well established that microRNAs (miRNAs) and their variants have an essential role in regulating the development of cardiovascular physiology, thus impacting the pathophysiology of heart diseases. This study was designed to determine the possible association of miRNA polymorphisms (miRNA-146a rs2910164C/G and miR-4513 rs2168518G/A) with susceptibility to CHD in Egyptian patients and their correlation with different biochemical parameters. The study comprised 300 participants, including 200 unrelated patients with CHD and 100 healthy controls. Anthropometric and blood biochemical parameters were measured as well genetic analysis for rs2910164C/G and rs2168518G/A polymorphisms were performed for all subjects using TaqMan real-time PCR assay. Our results revealed that the biomedical parameters have a significant correlation between CHD patients and healthy controls with a p < 0.05. Analyses of genotype distribution for (rs2910164 and rs2168518) revealed a significant association with CHD [odd ratio = 4.54, confidence interval (CI 95%) = (2.41-8.53)] and [odd ratio = 0.88, (CI 95%) = (0.83-0.92)], respectively. Furthermore, a statistically significant difference was detected between lipid profile levels and both rs2910164 and rs2168518 polymorphisms. The present study's findings indicated that the selected polymorphisms, miR-146a rs2910164 and miR-4513 rs2168518 could represent a useful biomarker for susceptibility to CHD in the Egyptian population. These genetic characteristics and personal habits and environmental factors may contribute to the development of CHD.

Photodynamic Effects with 5-Aminolevulinic Acid on Cytokines and Exosomes in Human Peripheral Blood Mononuclear Cells from Patients with Crohn's Disease

Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) which is the precursor of the photosensitizer protoporphyrin IX (PpIX) is an available treatment for several diseases. ALA-PDT induces the apoptosis and necrosis of target lesions. We have recently reported the effects of ALA-PDT on cytokines and exosomes of human healthy peripheral blood mononuclear cells (PBMCs). This study has investigated the ALA-PDT-mediated effects on PBMC subsets from patients with active Crohn's disease (CD). No effects on lymphocyte survival after ALA-PDT were observed, although the survival of CD3^-/CD19⁺ B-cells seemed slightly reduced in some samples. Interestingly, ALA-PDT clearly killed monocytes. The subcellular levels of cytokines and exosomes associated with inflammation were widely downregulated, which is consistent with our previous findings in PBMCs from healthy human subjects. These results suggest that ALA-PDT may be a potential treatment candidate for CD and other immune-mediated diseases.

Exosome engineering in cell therapy and drug delivery

Cell-derived exosomes have opened new horizons in modern therapy for advanced drug delivery and therapeutic applications, due to their key features such as low immunogenicity, high physicochemical stability, capacity to penetrate into tissues, and the innate capacity to communicate with other cells over long distances. Exosome-based liquid biopsy has been potentially used for the diagnosis and prognosis of a range of disorders. Exosomes deliver therapeutic agents, including immunological modulators, therapeutic drugs, and antisense oligonucleotides to certain targets, and can be used as vaccines, though their clinical application is still far from reality. Producing exosomes on a large-scale is restricted to their low circulation lifetime, weak targeting capacity, and inappropriate controls, which need to be refined before being implemented in practice. Several bioengineering methods have been used for refining therapeutic applications of exosomes and promoting their effectiveness, on the one hand, and addressing the existing challenges, on the other. In the short run, new diagnostic platforms and emerging therapeutic strategies will further develop exosome engineering and therapeutic potential. This requires a thorough analysis of exosome engineering approaches along with their merits and drawbacks, as outlined in this paper. The present study is a comprehensive review of novel techniques for exosome development in terms of circulation time in the body, targeting capacity, and higher drug loading/delivery efficacies.