The role of extracellular vesicles in animal reproduction and diseases

Progress in the application of mesenchymal stem cells to attenuate apoptosis in diabetic kidney disease

Diabetic kidney disease (DKD) has a high incidence and mortality rate and lacks effective preventive and therapeutic methods. Apoptosis is one of the main reasons for the occurrence and development of DKD. Mesenchymal stem cells (MSCs) have shown great promise in tissue regeneration for DKD treatment and have protective effects against DKD, including decreased blood glucose and urinary protein levels and improved renal function. MSCs can directly differentiate into kidney cells or act via paracrine mechanisms to reduce apoptosis in DKD by modulating signaling pathways. MSC-derived extracellular vesicles (MSC-EVs) mitigate apoptosis and DKD-related symptoms by transferring miRNAs to target cells or organs. However, studies on the regulatory mechanisms of MSCs and MSC-EVs in apoptosis in DKD are insufficient. This review comprehensively examines the mechanisms of apoptosis in DKD and research progress regarding the roles of MSCs and MSC-EVs in the disease process.

Cadmium-induced disruption of exosomal secretion and cellular pathways in leydig cells

Cadmium is a toxic heavy metal, disrupts different cellular secretions and induce pathological changes in the male reproductive system. However, cadmium-induced disruption of exosomal secretion and cellular pathways in Leydig cells is largely unknown. In this study, 30 C57BL/6 male mice were divided into two groups: one receiving purified water and the other 50 mg/L CdCl2 for three months. This is a first report, both in vivo and in vitro analyses showed that the control group exhibited strong immunoreactivity and immunosignaling with high secretion of exosomal proteins CD63 and multivesicular bodies (MVBs) through immunohistochemistry, immunofluorescence, and transmission electron microscopy. Leydig cells in the control group maintained a normal steroidogenic pathway, supporting the production of healthy, motile spermatozoa. Conversely, the cadmium-treated group showed irregularly dispersed Leydig cells with condensed nuclei and vacuolated mitochondria. Cadmium exposure led to reduced immunoreactivity, immunosignaling, and expression of CD63 in Leydig cells, with a noticeable lack of MVBs secretion. Additionally, cadmium significantly down-regulated the Steroidogenesis regulatory proteins STAR, CYP11A1, CYP17A1, 3BHSD1, 17BHSD1 and AR of Leydig cells. It also disrupted autophagic flux evidenced by increased expression of ATG5, ATG7, LC3, P62, and LAMP2 proteins. Furthermore, cadmium up-regulated apoptotic proteins (Caspase-3, Caspase-8, and Bax) and down-regulated the anti-apoptotic protein Bcl-2. This study provides novel insights into the detrimental effects of cadmium on Leydig cells' secretory pathways, highlighting disruptions in exosomal-MVBs secretion, autophagy and apoptosis, thereby posing significant risks to male fertility.

Egg exosome miR-145-5p decreases mitochondrial ROS to protect chicken embryo hepatocytes against apoptosis through targeting MAPK10

BACKGROUND

Higher embryonic mortality, especially in aged breeding hens, is associated with insufficient hepatic functionality in maintaining redox homeostasis. Our previous study demonstrated that egg exosome-derived miRNAs may play a key role in modulating embryonic oxidation-reduction process, whereas the exact function and mechanism were still poorly understood. The present study aimed to investigate the roles of egg exosome miRNAs in maintaining dynamic equilibrium of free radicals and peroxide agents in embryonic liver, as well as demonstrate the specific mechanism using oxidative stress-challenged hepatocytes.

RESULTS

Compared to 36-week-old breeding hens, decreased hatchability and increased embryonic mortality were observed in 65-week-old breeding hens. Meanwhile, the older group showed the increased MDA levels and decreased SOD and GSH-Px activities in embryonic liver, muscle and serum. Embryonic mortality was significantly positively correlated with MDA level and negatively correlated with GSH-Px activity in embryonic liver. In addition, 363 differentially expressed genes (DEGs) were identified in embryonic liver, 13 differentially expressed miRNAs (DE-miRNAs) were identified in egg exosomes. These DEGs and DE-miRNAs were involved in oxidoreductase activity, glutathione metabolic process, MAPK signaling pathway, apoptosis and autophagy. miRNA-mRNA network analysis further found that DEGs targeted by DE-miRNAs were mainly enriched in programmed cell death, such as apoptosis and autophagy. Wherein, MAPK10 with highest MCC and AUC values was significantly related to GSH-Px activity and MDA level, and served as the target gene of miR-145-5p based on dual luciferase reporter experiment and correlation analysis. Bioinformatics analysis found that miR-145-5p/MAPK10 axis might alleviate peroxide generation and apoptosis. In primary hepatocytes of chick embryos, miR-145-5p transfection significantly reversed H2O2-induced mitochondrial ROS increase, MAPK10, BAX and CASP3 overexpression and excessive apoptosis.

CONCLUSION

Exosome miR-145-5p in eggs could target MAPK10 and decrease mitochondrial ROS, attenuating oxidative damage and apoptosis in hepatocytes of chick embryos. These findings may provide new theoretical basis for the improvement of maternal physiological status to maintain embryonic redox homeostasis by nutritional or genetic modifications.

MiR-519d-3p from Placenta-Derived Exosomes Induce Immune Intolerance Regulating Immune Cells, Contributing to the Pathogenesis of Preeclampsia

BACKGROUND

MiR-519d-3p, also called specific placenta biomarkers, is a member of the Chromosome 19 miRNA Cluster (C19MC) with the highest concentrations of miRNAs in human placenta and maternal serum. These miRNAs are secreted by fetal trophoblast cells within extracellular vesicles (EVs) and interact with the mother's immune cells, which has been proposed to be crucial for immunological tolerance at the placental-maternal interface. A key mechanism in preeclampsia, a multifactorial, multipath hypertensive pregnancy illness, is an immunological imbalance between the mother and the fetus.

METHODS

Using Next Generation Sequencing, we determined that the placenta-derived Exosomes (pEXOs) of preeclamptic patients had elevated expression of miR-519. To further develop an in vitro model of trophoblast-immune cell communication, HTR-8/Svneo cells and Jurkat T cells were employed and we utilized experiments such as Western blot (WB), Real-Time Quantitative Reverse Transcription Polymerase Chain Reaction (RT-qPCR), Cell-Counting-Kit-8 (CCK-8) cell proliferation analysis, cell apoptosis analysis, and other techniques to accomplish research.

RESULTS

It was discovered that miR-519d-3p in pEXOs promoted Jurkat T cell proliferation, inhibited apoptosis, and induced Jurkat T cell differentiation toward Th17.

CONCLUSION

MiR-519d-3p in pEXOs disrupts immune tolerance at the maternal-placental interface by encouraging Jurkat T cell proliferation, preventing Jurkat T cell apoptosis, and creating an imbalance in Th17/Treg differentiation. This likely leads to SIRS and unfavorable pregnancy complications like preeclampsia.

Exploring extracellular vesicles as novel therapeutic agents for intervertebral disc degeneration: delivery, applications, and mechanisms

Intervertebral disc degeneration is a multifactorial degenerative disease that poses a significant threat to the health of the elderly population. Current treatments primarily focus on physical therapy, medication, and surgery to alleviate symptoms associated with disc compression but do not address the progression of degeneration. Therefore, this review aimed to explore the potential of extracellular vesicle therapy as a novel preventive strategy to delay degeneration and enhance tissue repair in intervertebral discs. We cover the pathogenic mechanisms underlying intervertebral disc degeneration, including inflammation, apoptosis, pyroptosis, ferroptosis, autophagy dysregulation, and the roles of non-coding RNAs. Subsequently, we discussed the therapeutic potential of extracellular vesicles and their molecular components, such as proteins, RNAs, and lipids, in modulating these pathways to counter intervertebral disc degeneration. We provides a comprehensive review of the significant role of extracellular vesicle cargo in mediating repair mechanisms. It discusses the functional enhancement advantages exhibited by extracellular vesicles under current bioengineering modifications and drug loading. The challenges and future prospects of utilizing extracellular vesicle therapy to treat this degenerative condition are also summarized.

The role of extracellular vesicles in embryo development: implications for reproductive health and therapeutic potential

Extracellular vesicles (EVs) contain various biological molecules, such as proteins, lipids, and diverse nucleic acids, which alter various physiological and pathological processes in recipient cells. This review focuses on the current understanding of the biological characteristics of EVs on embryo development and their potential therapeutic value in treating reproductive disorders. EVs play a crucial role in early embryo development, from fertilization to the pre-implantation stage, gastrulation, cell differentiation, and organogenesis. During the pre-implantation period, EVs interact with maternal reproductive tissue and promote implantation receptivity. In gastrulation, EVs regulate cell differentiation, contributing to tissue formation and maintenance. Abnormal bioactive molecules in EVs are closely related to developmental disorders. Thus, EVs have the potential to serve as biomarkers. Moreover, EVs can serve as therapeutic agents, delivering genetic material for targeted tissue/organs. The findings of this review highlight the potential role of EVs in intercellular signaling during embryo development. This can help advance assisted reproductive technologies and therapies to overcome infertility issues and developmental disorders.

Potential and challenges of utilizing exosomes in osteoarthritis therapy (Review)

Exosomes are integral to the pathophysiology of osteoarthritis (OA) due to their roles in mediating intercellular communication and regulating inflammatory processes. Exosomes are integral to the transport of bioactive molecules, such as proteins, lipids and nucleic acids, which can influence chondrocyte behavior and joint homeostasis. Given their properties of regeneration and ability to target damaged tissues, exosomes represent a promising therapeutic avenue for OA treatment. Exosomes have potential in promoting cartilage repair, reducing inflammation and improving overall joint function. However, several challenges remain, including the need for standardized isolation and characterization methods, variability in exosomal content, and regulatory hurdles. The present review aims to provide a comprehensive overview of the current understanding of exosome mechanisms in OA and their therapeutic potential, while also addressing the ongoing challenges faced in translating these findings into clinical practice. By consolidating existing research, the present review aims to pave the way for future studies aimed at optimizing exosome‑based therapies for effective OA management.

Exosomal ncRNAs in reproductive cancers†

Extracellular vesicles, particularly exosomes, play a pivotal role in the cellular mechanisms underlying cancer. This review explores the various functions of exosomes in the progression, growth, and metastasis of cancers affecting the male and female reproductive systems. Exosomes are identified as key mediators in intercellular communication, capable of transferring bioactive molecules such as microRNAs, proteins, and other nucleic acids that influence cancer cell behavior and tumor microenvironment interactions. It has been shown that non-coding RNAs transported by exosomes play an important role in tumor growth processes. Significant molecules that may serve as biomarkers in the development and progression of male reproductive cancers include miR-125a-5p, miR-21, miR-375, the miR-371 ~ 373 cluster, and miR-145-5p. For female reproductive cancers, significant microRNAs include miR-26a-5p, miR-148b, miR-205, and miRNA-423-3p. This review highlights the potential of these noncoding RNAs as biomarkers and prognostics in tumor diagnostics. Understanding the diverse roles of exosomes may hold promise for developing new therapeutic strategies and improving treatment outcomes for cancer patients.

Unlocking Gamete Quality Through Extracellular Vesicles: Emerging Perspectives

Extracellular vesicles (EVs) are gaining recognition for their essential role in enhancing gamete quality and improving outcomes in assisted reproductive technologies. These nanosized particles, released by cells, carry proteins, lipids, and RNAs, facilitating critical cell communication and offering the potential to enhance gamete maturation and improve fertilization rates. Most research on males has concentrated on seminal plasma, a complex fluid produced by the testes and accessory glands vital in modulating sperm fertility potential. The components of seminal plasma significantly affect sperm functionality, embryo survival, and placental development, making this a prominent area of interest in reproductive biology. The EVs within seminal plasma contribute to maintaining sperm membrane stability, enhancing motility, and promoting capacitation, which may influence the female reproductive tract following mating. In females, EVs have been identified in both the follicular and uterine environments, where effective embryo-maternal communication is crucial. The oviduct epithelium supports gamete transport and early embryonic development, with EVs found in oviductal fluid playing a key role in reproductive processes. These EVs support the embryo's growth in the nutrient-rich uterine environment. These important studies underscore the significant role of EVs in transporting essential molecular compounds to gametes and embryos, leading to an enhanced understanding and potential manipulation of reproductive processes. This review aims to summarize the current research on the benefits of EVs in gamete manipulation and embryo development, highlighting their promising implications for reproductive health.

Regulatory roles of extracellular vesicles in pregnancy complications

BACKGROUND

Extracellular vesicles (EVs) are heterogeneous membranous structures released by various cell types, including large vesicles, microvesicles (MVs), and exosomes. These vesicles play crucial roles in intercellular communication within interstitial fluids and are involved in numerous physiological and pathological processes.

AIM OF REVIEW

This review aims to examine the regulatory roles of EVs in pregnancy complications, focusing on their involvement in gestational diabetes mellitus (GDM), preeclampsia (PE), and preterm birth (PTB).

KEY SCIENTIFIC CONCEPTS OF REVIEW

Placenta- and embryo-derived EVs have gained significant attention for their biological roles due to their effects on inflammation, immune response and immunomodulation. Recent research highlights the importance of EVs in embryonic development and gestation. During pregnancy, several EVs functioned in complex endocrine regulation and pregnancy complications that can affect both the mother and fetus, with long-term cardiovascular and metabolic risks. This review discusses the current evidence on how EVs modulate pregnancy outcomes and explores their biological roles in the pathology of GDM, PE, and PTB. In spite of the current difficulties in relating these findings to the pathogenesis of pregnancy complications and the insufficient evidence for clinical practice, the potential impact of specific proteins and miRNAs transported by EVs is noteworthy on the emergence of pregnancy complications. Future research should continue to explore the complex interactions mediated by EVs to develop novel diagnostic and therapeutic strategies for pregnancy-related disorders.

The Influence of Ovarian-Derived Extracellular Vesicles in Reproduction

In this chapter, we explore the multifaceted roles of extracellular vesicles (EVs) in ovarian biology, focusing on their contributions to folliculogenesis, oocyte competence, corpus luteum function, and immune response regulation. EVs, particularly those derived from follicular fluid (ffEVs), are crucial mediators of cell-to-cell communication within the ovarian follicle, influencing processes such as meiotic progression, stress response, and hormonal regulation. We review preexisting literature, highlighting key findings on the molecular cargo of EVs, such as miRNAs and proteins, and their involvement in regulating the function of the follicle cells. Additionally, the influence of EVs on the immune responses within the ovary was also addressed. Some attention is given to the potential of EVs as non-invasive biomarkers and therapeutic tools, particularly in addressing conditions like premature ovarian insufficiency and polycystic ovary syndrome. By discussing the existing challenges and emerging research, we hope that this chapter will provide a deeper understanding of EVs' therapeutic potential and offer insights or suggestions for advancing assisted reproductive technologies.

RNA profiles differ between small and large extracellular vesicle subsets isolated from porcine seminal plasma

BACKGROUND

Extracellular vesicles (EVs) are essential for cell-to-cell communication because they transport functionally active molecules, including proteins, RNA, and lipids, from secretory cells to nearby or distant target cells. Seminal plasma contains a large number of EVs (sEVs) that are phenotypically heterogeneous. The aim of the present study was to identify the RNA species contained in two subsets of porcine sEVs of different sizes, namely small sEVs (S-sEVs) and large sEVs (L-sEVs). The two subsets of sEVs were isolated from 54 seminal plasma samples by a method combining serial centrifugations, size exclusion chromatography, and ultrafiltration. The sEVs were characterized using an orthogonal approach. Analysis of RNA content and quantification were performed using RNA-seq analysis.

RESULTS

The two subsets of sEVs had different size distributions (P < 0.001). They also showed differences in concentration, morphology, and specific protein markers (P < 0.05). A total of 735 RNAs were identified and quantified, which included: (1) mRNAs, rRNAs, snoRNAs, snRNAs, tRNAs, other ncRNAs (termed as "all RNAs"), (2) miRNAs and (3) piRNAs. The distribution pattern of these RNA classes differed between S-sEVs and L-sEVs (P < 0.05). More than half of "all RNAs", miRNAs and piRNAs were found to be differentially abundant between S- and L-sEVs (FDR < 0.1%). Among the differentially abundant RNAs, "all RNAs" were more abundant in L- than in S-sEVs, whereas the most of the miRNAs were more abundant in S- than in L-sEVs. Differentially abundant piRNAs were equally distributed between S- and L-sEVs. Some of the all RNAs and miRNAs found to be differentially abundant between S- and L-sEVs were associated with sperm quality and functionality and male fertility success.

CONCLUSIONS

Small and large sEVs isolated from porcine seminal plasma show quantitative differences in RNA content. These differences would suggest that each sEV subtype exerts different functional activities in the targeted cells, namely spermatozoa and functional cells of the female reproductive tract.

The Role of Extracellular Vesicles in the Development and Treatment of Psoriasis: Narrative Review

Psoriasis is a chronic inflammatory polygenic disease with significant impacts on skin and joints, leading to substantial treatment challenges and healthcare costs. The quest for novel therapeutic avenues has recently highlighted extracellular vesicles (EVs) due to their potential as biomarkers and therapeutic agents in autoimmune diseases, including psoriasis. EVs are nano-sized, lipid membrane-bound particles secreted by cells that have emerged as promising tools for targeted drug delivery, owing to their unique structure. This review delves into how EVs, either as mediators of cell communication or via their cargo (such as miRNA), directly participate in the pathology of psoriasis, influencing processes such as immune regulation, cell proliferation, and differentiation. Furthermore, this review explores the innovative application of EVs in psoriasis treatment, both as direct therapeutic agents and as vehicles for drug delivery, offering a novel approach to overcoming the current treatment limitations.

miR-21-5p Enriched Exosomes from Human Embryonic Stem Cells Promote Osteogenesis via YAP1 Modulation

Purpose

To investigate the osteogenic potential of human embryonic stem cell-derived exosomes (hESC-Exos) and their effects on the differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs).

Methods

hESC-Exos were isolated and characterized using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and Western blotting. hUCMSCs were cultured with hESC-Exos to assess osteogenic differentiation through alizarin red staining, quantitative PCR (qPCR), and Western blotting. miRNA profiling of hESC-Exos was performed using miRNA microarray analysis. In vivo bone regeneration was evaluated using an ovariectomized rat model with bone defects treated with exosome-loaded scaffolds.

Results

hESC-Exos significantly promoted the osteogenic differentiation of hUCMSCs, as evidenced by increased alizarin red staining and the upregulation of osteogenesis-related genes and proteins (ALP, RUNX2, OCN). miRNA analysis revealed that miR-21-5p is a key regulator that targets YAP1 and activates the Wnt/β-catenin signaling pathway. In vivo, hESC-Exos enhanced bone repair in ovariectomized rats, as demonstrated by increased bone mineral density and improved bone microarchitecture compared to those in controls.

Conclusion

hESC-Exos exhibit significant osteogenic potential by promoting the differentiation of hUCMSCs and enhancing bone regeneration in vivo. This study revealed that the miR-21-5p-YAP1/β-catenin axis is a critical pathway, suggesting that the use of hESC-Exos is a promising therapeutic strategy for bone regeneration and repair.

The role of reproductive tract extracellular vesicles on boar sperm function

Extracellular vesicles (EVs) are abundant in reproductive tract fluids and serve as important mediators of paracrine communication, influencing the function of gametes. Sperm undergo development in the male reproductive tract and exert their function within the female reproductive tract, engaging in interactions with various types of EVs present throughout the reproductive system. Previous studies have demonstrated that both male and female reproductive tract EVs can impact sperm function by transferring regulatory cargoes to them. Nevertheless, inconsistencies of previous research regarding the effects of EVs on sperm function, coupled with a lack of investigation into the influence of female reproductive tract EVs on sperm fertilization, have left the true role and underlying mechanisms of reproductive tract EVs on sperm function largely unexplored. Given that pigs represent significant economic livestock and serve as an ideal biomedical model for human diseases, this review aims to provide a comprehensive summary of the current knowledge regarding reproductive tract EVs and their influence on boar sperm function, while highlighting their potential roles. We anticipate that this review will facilitate future research on reproductive tract EVs and their impact on sperm function, contributing to improved animal reproductive efficiency and advancements in the treatment of male infertility.

Reproductive physiology of the boar: What defines the potential fertility of an ejaculate?

Despite decades of research and handling of semen for use in artificial insemination (AI) and other assisted reproductive technologies, 5-10% of selected boar sires are still considered sub-fertile, escaping current assessment methods for sperm quality and resilience to preservation. As end-product, the ejaculate (emitted spermatozoa sequentially exposed to the composite seminal plasma, the SP) ought to define the homeostasis of the testes, the epididymis, and the accessory sexual glands. Yet, linking findings in the ejaculate to sperm production biology and fertility is suboptimal. The present essay critically reviews how the ejaculate of a fertile boar can help us to diagnose both reproductive health and resilience to semen handling, focusing on methods -available and under development- to identify suitable biomarkers for cryotolerance and fertility. Bulk SP, semen proteins and microRNAs (miRNAs) have, albeit linked to sperm function and fertility after AI, failed to enhance reproductive outcomes at commercial level, perhaps for just being components of a complex functional pathway. Hence, focus is now on the interaction sperm-SP, comparing in vivo with ex vivo, and regarding nano-sized lipid bilayer seminal extracellular vesicles (sEVs) as priority. sEVs transport fragile molecules (lipids, proteins, nucleic acids) which, shielded from degradation, mediate cell-to-cell communication with spermatozoa and the female internal genital tract. Such interaction modulates essential reproductive processes, from sperm homeostasis to immunological female tolerance. sEVs can be harvested, characterized, stored, and manipulated, e.g. can be used for andrological diagnosis, selection of breeders, and alternatively be used as additives to improve cryosurvival and fertility.

ADSC-derived exosomes provide neuroprotection in sepsis-associated encephalopathy by regulating hippocampal pyroptosis

AIMS

Adipose-derived stem cell (ADSC)-derived exosomes have been recognized for their neuroprotective effects in various neurological diseases. This study investigates the potential neuroprotective effects of ADSC-derived exosomes in sepsis-associated encephalopathy (SAE).

METHODS

Behavioral cognitive functions were evaluated using the open field test, Y-maze test, and novel object recognition test. Brain activity was assessed through functional magnetic resonance imaging (fMRI). Pyroptosis was measured using immunofluorescence staining and western blotting.

RESULTS

Our findings indicate that ADSC-derived exosomes mitigate cognitive impairment, improve survival rates, and prevent weight loss in SAE mice. Additionally, exosomes protect hippocampal function in SAE mice, as demonstrated by fMRI evaluations. Furthermore, SAE mice exhibit neuronal damage and infiltration of inflammatory cells in the hippocampus, conditions which are reversed by exosome treatment. Moreover, our study highlights the downstream regulatory role of the NLRP3/caspase-1/GSDMD signaling pathway as a crucial mechanism in alleviating hippocampal inflammation.

CONCLUSION

ADSC-derived exosomes confer neuroprotection in SAE models by mediating the NLRP3/caspase-1/GSDMD pathway, thereby ameliorating cognitive impairment.

Progress in extracellular vesicle homeostasis as it relates to cardiovascular diseases

Extracellular vesicles (EVs) are involved in both physiological and pathological processes in many organ systems and are essential in mediating intercellular communication and maintaining organismal homeostasis. It is helpful to propose new strategies for disease treatment by elucidating the mechanisms of EV release and sorting. An increasing number of studies have shown that there is specific homeostasis in EVs, which is helpful for the human body to carry out physiological activities. In contrast, an EV homeostasis im-balance promotes or accelerates disease onset and development. Alternatively, regulating the quality of EVs can maintain homeostasis and even achieve the purpose of treating conditions. An analysis of the role of EV homeostasis in the onset and development of cardiovascular disease is presented in this review. This article also summarizes the methods that regulate EV homeostasis and their application in cardiovascular diseases. In particular, this study focuses on the connection between EV steady states and the cardiovascular system and the potential value of EVs in treating cardiovascular diseases.

Profiling of m6A methylation in porcine intramuscular adipocytes and unravelling PHKG1 represses porcine intramuscular lipid deposition in an m6A-dependent manner

Intramuscular fat (IMF) content is mainly determined by intramuscular preadipocyte adipogenesis. Epigenetic modifications are known to have a regulatory effect on IMF. As N6-methyladenosine (m6A) is the most abundant epigenetic modification in eukaryotic RNAs. In the present study, we used m6A methylation and RNA sequencing (seq) to identify the m6A-modified RNAs associated with the adipogenic differentiation of intramuscular preadipocytes. Among them, the expression and m6A level of phosphorylase kinase subunit G1 (PHKG1) were found to be significantly changed during adipogenesis. Further studies revealed that knockdown of the methylase METTL3 decreased the m6A methylation of PHKG1 and led to a reduction in PHKG1. Moreover, knockdown of PHKG1 promoted adipogenic differentiation by upregulating the expression of adipogenic genes. In addition, we found that the IMF content in the longissimus thoracis (LT) of Bamei (BM) pigs was greater than that in Large White (LW) pigs, whereas the m6A and PHKG1 expression levels were lower in BM pigs. These findings indicate that the m6A level and expression of PHKG1 were significantly correlated with IMF content and meat quality. In conclusion, this study sheds light on the mechanism by which m6A modification regulates IMF deposition.

Oviductal extracellular vesicles miRNA cargo varies in response to embryos and their quality

BACKGROUND

Increasing evidence points to an active role of oviductal extracellular vesicles (oEVs) in the early embryo-maternal dialogue. However, it remains unclear whether oEVs contribute to the recognition of the presence of embryos and their quality in the oviduct. Hence, we examined whether the molecular cargo of oEVs secreted by bovine oviduct epithelial cells (BOEC) differs depending on the presence of good (≥ 8 cells, G) or poor (< 8 cells, P) quality embryos. In addition, differences in RNA profiles between G and P embryos were analyzed in attempt to distinguish oEVs and embryonic EVs cargos.

METHODS

For this purpose, primary BOEC were co-cultured with in vitro produced embryos (IVP) 53 h post fertilization as follows: BOEC with G embryos (BGE); BOEC with P embryos (BPE); G embryos alone (GE); P embryos alone (PE); BOEC alone (B) and medium control (M). After 24 h of co-culture, conditioned media were collected from all groups and EVs were isolated and characterized. MicroRNA profiling of EVs and embryos was performed by small RNA-sequencing.

RESULTS

In EVs, 84 miRNAs were identified, with 8 differentially abundant (DA) miRNAs for BGE vs. B and 4 for BPE vs. B (P-value < 0.01). In embryos, 187 miRNAs were identified, with 12 DA miRNAs for BGE vs. BPE, 3 for G vs. P, 8 for BGE vs. GE, and 11 for BPE vs. PE (P-value < 0.01).

CONCLUSIONS

These results indicated that oEVs are involved in the oviductal-embryo recognition and pointed to specific miRNAs with signaling and supporting roles during early embryo development.

Effect of 3D and 2D cell culture systems on trophoblast extracellular vesicle physico-chemical characteristics and potency

The growing understanding of the role of extracellular vesicles (EVs) in embryo-maternal communication has sparked considerable interest in their therapeutic potential within assisted reproductive technology, particularly in enhancing implantation success. However, the major obstacle remains the large-scale production of EVs, and there is still a gap in understanding how different culture systems affect the characteristics of the EVs. In the current study, trophoblast analogue human chorionic carcinoma cell line was cultivated in both conventional monolayer culture (2D) and as spheroids in suspension culture (3D) and how the cell growth environment affects the physical, biochemical and cellular signalling properties of EVs produced by them was studied. Interestingly, the 3D system was more active in secreting EVs compared to the 2D system, while no significant differences were observed in terms of morphology, size, and classical EV protein marker expression between EVs derived from the two culture systems. There were substantial differences in the proteomic cargo profile and cellular signalling potency of EVs derived from the two culture systems. Notably, 2D EVs were more potent in inducing a cellular response in endometrial epithelial cells (EECs) compared to 3D EVs. Therefore, it is essential to recognize that the biological activity of EVs depends not only on the cell of origin but also on the cellular microenvironment of the parent cell. In conclusion, caution is warranted when selecting an EV production platform, especially for assessing the functional and therapeutic potential of EVs through in vitro studies.

Dendritic cell-derived exosome (DEX) therapy for digestive system cancers: Recent advances and future prospect

Tumor-mediated immunosuppression is a fundamental obstacle to the development of dendritic cell (DC)-based cancer vaccines, which despite their ability to stimulate host anti-tumor CD8 T cell immunity, have not been able to generate meaningful therapeutic responses. Exosomes are inactive membrane vesicles that are nanoscale in size and are produced by the endocytic pathway. They are essential for intercellular communication. Additionally, DC-derived exosomes (DEXs) contained MHC class I/II (MHCI/II), which is frequently complexed with antigens and co-stimulatory molecules and is therefore able to prime CD4 and CD8 T cells that are specific to particular antigens. Indeed, vaccines with DEXs have been shown to exhibit better anti-tumor efficacy in eradicating tumors compared to DC vaccines in pre-clinical models of digestive system tumors. Also, there is room for improvement in the tumor antigenic peptide (TAA) selection process. DCs release highly targeted exosomes when the right antigenic peptide is chosen, which could aid in the creation of DEX-based antitumor vaccines that elicit more targeted immune responses. Coupled with their resistance to tumor immunosuppression, DEXs-based cancer vaccines have been heralded as the superior alternative cell-free therapeutic vaccines over DC vaccines to treat digestive system tumors. In this review, current studies of DEXs cancer vaccines as well as potential future directions will be deliberated.

Extracellular Vesicles in Pathophysiology: A Prudent Target That Requires Careful Consideration

Extracellular vesicles (EVs) are membrane-bound particles released by cells to perform multitudes of biological functions. Owing to their significant implications in diseases, the pathophysiological role of EVs continues to be extensively studied, leading research to neglect the need to explore their role in normal physiology. Despite this, many identified physiological functions of EVs, including, but not limited to, tissue repair, early development and aging, are attributed to their modulatory role in various signaling pathways via intercellular communication. EVs are widely perceived as a potential therapeutic strategy for better prognosis, primarily through utilization as a mode of delivery vehicle. Moreover, disease-associated EVs serve as candidates for the targeted inhibition by pharmacological or genetic means. However, these attempts are often accompanied by major challenges, such as off-target effects, which may result in adverse phenotypes. This renders the clinical efficacy of EVs elusive, indicating that further understanding of the specific role of EVs in physiology may enhance their utility. This review highlights the essential role of EVs in maintaining cellular homeostasis under different physiological settings, and also discusses the various aspects that may potentially hinder the robust utility of EV-based therapeutics.

Increased levels of villus-derived exosomal miR-29a-3p in normal pregnancy than uRPL patients suppresses decidual NK cell production of interferon-γ and exerts a therapeutic effect in abortion-prone mice

OBJECTIVE

Recurrent pregnancy loss (RPL) patients have higher absolute numbers of decidual natural killer (dNK) cells with elevated intracellular IFN-γ levels leading to a pro-inflammatory cytokine milieu, which contributes to RPL pathogenesis. The main objective of this study was twofold: first to explore the regulatory effects and mechanisms of villus-derived exosomes (vEXOs) from induced abortion patients or RPL patients at the level of intracellular IFN-γ in dNK cells; second to determine the validity of application of vEXOs in the treatment of unexplained RPL (uRPL) through in vitro experiments and mouse models.

METHODS

Exosomes were isolated from villus explants by ultracentrifugation, co-cultured with dNK cells, and purified by enzymatic digestion and magnetically activated cell sorting. Flow cytometry, enzyme-linked immunosorbent assays, and RT-qPCR were used to determine IFN-γ levels. Comparative miRNA analysis of vEXOs from induced abortion (IA) and uRPL patients was used to screen potential candidates involved in dNK regulation, which was further confirmed by luciferase reporter assays. IA-vEXOs were electroporated with therapeutic miRNAs and encapsulated in a China Food and Drug Administration (CFDA)-approved hyaluronate gel (HA-Gel), which has been used as a clinical biomaterial in cell therapy for > 30 years. In vivo tracking was performed using 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyaine iodide (DiR) labelling. Tail-vein and uterine horn injections were used to evaluate therapeutic effects of the engineered exosomes in an abortion-prone mouse model (CBA/J × DBA/2 J). Placental growth was evaluated based on placental weight. IFN-γ mRNA levels in mouse placentas were measured by RT-qPCR.

RESULTS

IFN-γ levels were significantly higher in dNK cells of uRPL patients than in IA patients. Both uRPL-vEXOs and IA-vEXOs could be efficiently internalized by dNK cells, whereas uRPL-vEXOs could not reduce the expression of IFN-γ by dNK cells as much as IA-vEXOs. Mechanistically, miR-29a-3p was delivered by vEXOs to inhibit IFN-γ production by binding to the 3' UTR of IFN-γ mRNA in dNK cells. For in vivo treatment, application of the HA-Gel effectively prolonged the residence time of vEXOs in the uterine cavity via sustained release. Engineered vEXOs loaded with miR-29a-3p reduced the embryo resorption rate in RPL mice with no signs of systemic toxicity.

CONCLUSION

Our study provides the first evidence that villi can regulate dNK cell production of IFN-γ via exosome-mediated transfer of miR-29a-3p, which deepens our understanding of maternal-fetal immune tolerance for pregnancy maintenance. Based on this, we developed a new strategy to mix engineered vEXOs with HA-Gel, which exhibited good therapeutic effects in mice with uRPL and could be used for potential clinical applications in uRPL treatment.

Seminal extracellular vesicles alter porcine in vitro fertilization outcome by modulating sperm metabolism

Porcine seminal plasma (SP) is loaded with a heterogeneous population of extracellular vesicles (sEVs) that modulate several reproductive-related processes. This study investigated the effect of two sEV subsets, small (S-sEVs) and large (L-sEVs), on porcine in vitro fertilization (IVF). The sEVs were isolated from nine SP pools (five ejaculates/pool) using a size-exclusion chromatography-based procedure and characterized for quantity (total protein), morphology (cryogenic electron microscopy), size distribution (dynamic light scattering), purity and EV-protein markers (flow cytometry; albumin, CD81, HSP90β). The characterization confirmed the existence of two subsets of high purity (low albumin content) sEVs that differed in size (S- and L-sEVs). In vitro fertilization was performed with in vitro matured oocytes and frozen-thawed spermatozoa and the IVF medium was supplemented during gamete coincubation (1 h at 38.5 °C, 5 % CO2 in a humidified atmosphere) with three different concentrations of each sEV subset: 0 (control, without sEVs), 0.1, and 0.2 mg/mL. The first experiment showed that sEVs, regardless of subset and concentration, decreased penetration rates and total IVF efficiency (P < 0.0001). In a subsequent experiment, it was shown that sEVs, regardless of subset and concentration, impaired the ability of spermatozoa to bind to the zona pellucida of oocytes (P < 0.0001). The following experiment showed that sEVs, regardless of the subset, bound to frozen-thawed sperm but not to in vitro matured oocytes, indicating that sEVs would affect sperm functionality but not oocyte functionality. The lack of effect on oocytes was confirmed by incubating sEVs with oocytes prior to IVF, achieving sperm-zona pellucida binding results similar to those of control. In the last experiment, conducted under IVF conditions, sperm functionality was analyzed in terms of tyrosine phosphorylation, acrosome integrity and metabolism. The sEVs, regardless of the subset, did not affect sperm tyrosine phosphorylation or acrosome integrity, but did influence sperm metabolism by decreasing sperm ATP production under capacitating conditions. In conclusion, this study demonstrated that the presence of sEVs on IVF medium impairs IVF outcomes, most likely by altering sperm metabolism.

Autophagy-Dependent Secretion: Crosstalk between Autophagy and Exosome Biogenesis

The cellular secretome is pivotal in mediating intercellular communication and coordinating responses to stressors. Exosomes, initially recognized for their role in waste disposal, have now emerged as key intercellular messengers with significant therapeutic and diagnostic potential. Similarly, autophagy has transcended its traditional role as a waste removal mechanism, emerging as a regulator of intracellular communication pathways and a contributor to a unique autophagy-dependent secretome. Secretory authophagy, initiated by various stress stimuli, prompts the selective release of proteins implicated in inflammation, including leaderless proteins that bypass the conventional endoplasmic reticulum-Golgi secretory pathway. This reflects the significant impact of stress-induced autophagy on cellular secretion profiles, including the modulation of exosome release. The convergence of exosome biogenesis and autophagy is exemplified by the formation of amphisomes, vesicles that integrate autophagic and endosomal pathways, indicating their synergistic interplay. Regulatory proteins common to both pathways, particularly mTORC1, emerge as potential therapeutic targets to alter cellular secretion profiles involved in various diseases. This review explores the dynamic interplay between autophagy and exosome formation, highlighting the potential to influence the secretome composition. While the modulation of exosome secretion and cytokine preconditioning is well-established in regenerative medicine, the strategic manipulation of autophagy is still underexplored, presenting a promising but uncharted therapeutic landscape.

Tumor-derived microvesicles for cancer therapy

Extracellular vesicles (EVs) are vesicles with lipid bilayer structures shed from the plasma membrane of cells. Microvesicles (MVs) are a subset of EVs containing proteins, lipids, nucleic acids, and other metabolites. MVs can be produced under specific cell stimulation conditions and isolated by modern separation technology. Due to their tumor homing and large volume, tumor cell-derived microvesicles (TMVs) have attracted interest recently and become excellent delivery carriers for therapeutic vaccines, imaging agents or antitumor drugs. However, preparing sufficient and high-purity TMVs and conducting clinical transformation has become a challenge in this field. In this review, the recent research achievements in the generation, isolation, characterization, modification, and application of TMVs in cancer therapy are reviewed, and the challenges facing therapeutic applications are also highlighted.

Extracellular vesicles in the breast cancer brain metastasis: physiological functions and clinical applications

Breast cancer, which exhibits an increasing incidence and high mortality rate among cancers, is predominantly attributed to metastatic malignancies. Brain metastasis, in particular, significantly contributes to the elevated mortality in breast cancer patients. Extracellular vesicles (EVs) are small lipid bilayer vesicles secreted by various cells that contain biomolecules such as nucleic acids and proteins. They deliver these bioactive molecules to recipient cells, thereby regulating signal transduction and protein expression levels. The relationship between breast cancer metastasis and EVs has been extensively investigated. In this review, we focus on the molecular mechanisms by which EVs promote brain metastasis in breast cancer. Additionally, we discuss the potential of EV-associated molecules as therapeutic targets and their relevance as early diagnostic markers for breast cancer brain metastasis.

Extracellular vesicle-coupled miRNA profiles of chicken seminal plasma and their potential interaction with recipient cells

The presence of EVs in seminal plasma (SPEVs) suggests their involvement on fertility via transmitting information between the original cells and recipient cells. SPEVs-coupled miRNAs have been shown to affect sperm motility, maturation, and capacitation in mammals, but rarely in poultry species. The present study aims to reveal the profile of SPEVs miRNAs and their potential effect on sperm storage and function in poultry. The SPEVs was successfully isolated from 4 different chicken breeds by ultracentrifugation and verified. Deep sequencing of SPEVs small RNA library of each breed identified 1077 miRNAs in total and 563 shared ones. The top 10 abundant miRNAs (such as miR-10-5p, miR-100-5p, and miR-10a-5p etc.) accounted for around 60% of total SPEVs miRNA reads and are highly conserved across species, predisposing their functional significance. Target genes prediction and functional enrichment analysis indicated that the most abundantly expressed miRNAs may regulate pathways like ubiquitin-mediated proteolysis, endocytosis, mitophagy, glycosphingolipid biosynthesis, fatty acid metabolism, and fatty acid elongation. The high abundant SPEVs-coupled miRNAs were found to target 107 and 64 functionally important mRNAs in the potential recipient cells, sperm and sperm storage tubules (SST) cells, respectively. The pathways that enriched by target mRNAs revealed that the SPEVs-coupled miRNA may rule the fertility by affecting the sperm maturation and regulating the female's immune response and lipid metabolism. In summary, this study presents the distinctive repertoire of SPEVs-coupled miRNAs, and extends our understanding about their potential roles in sperm maturation, capacitation, storage, and fertility, and may help to develop new therapeutic strategies for male infertility and sperm storage.

Biogenesis and function of exosome lncRNAs and their role in female pathological pregnancy

Preeclampsia, gestational diabetes mellitus, and recurrent spontaneous abortion are common maternal pregnancy complications that seriously endanger women's lives and health, and their occurrence is increasing year after year with a rejuvenation trend. In contrast to biomarkers found freely in tissues or body fluids, exosomes exist in a relatively independent environment and provide a higher level of stability. As backbone molecules, guidance molecules, and signaling molecules in the nucleus, lncRNAs can regulate gene expression. In the cytoplasm, lncRNAs can influence gene expression levels by modifying mRNA stability, acting as competitive endogenous RNAs to bind miRNAs, and so on. Exosomal lncRNAs can exist indefinitely and are important in intercellular communication and signal transduction. Changes in maternal serum exosome lncRNA expression can accurately and timely reflect the progression and regression of pregnancy-related diseases. The purpose of this paper is to provide a reference for clinical research on the pathogenesis, diagnosis, and treatment methods of pregnancy-related diseases by reviewing the role of exosome lncRNAs in female pathological pregnancy and related molecular mechanisms.

Dendritic Cell-Derived Exosomes in Cancer Immunotherapy

Exosomes are nanoscale vesicles released by diverse types of cells for complex intercellular communication. Numerous studies have shown that exosomes can regulate the body's immune response to tumor cells and interfere with the tumor microenvironment (TME). In clinical trials on dendritic cell (DC)-based antitumor vaccines, no satisfactory results have been achieved. However, recent studies suggested that DC-derived exosomes (DEXs) may be superior to DC-based antitumor vaccines in avoiding tumor cell-mediated immunosuppression. DEXs contain multiple DC-derived surface markers that capture tumor-associated antigens (TAAs) and promote immune cell-dependent tumor rejection. These findings indicate the necessity of the further development and improvement of DEX-based cell-free vaccines to complement chemotherapy, radiotherapy, and other immunotherapies. In this review, we highlighted the recent progress of DEXs in cancer immunotherapy, particularly by concentrating on landmark studies and the biological characterization of DEXs, and we summarized their important role in the tumor immune microenvironment (TIME) and clinical application in targeted cancer immunotherapy. This review could enhance comprehension of advances in cancer immunotherapy and contribute to the elucidation of how DEXs regulate the TIME, thereby providing a reference for utilizing DEX-based vaccines in clinical practice.

Mesenchymal Stromal Cells-Derived Extracellular Vesicles as Potential Treatments for Osteoarthritis

Osteoarthritis (OA) is a degenerative disease of the joints characterized by cartilage damage and severe pain. Despite various pharmacological and surgical interventions, current therapies fail to halt OA progression, leading to high morbidity and an economic burden. Thus, there is an urgent need for alternative therapeutic approaches that can effectively address the underlying pathophysiology of OA. Extracellular Vesicles (EVs) derived from mesenchymal stromal cells (MSCs) represent a new paradigm in OA treatment. MSC-EVs are small membranous particles released by MSCs during culture, both in vitro and in vivo. They possess regenerative properties and can attenuate inflammation, thereby promoting cartilage healing. Importantly, MSC-EVs have several advantages over MSCs as cell-based therapies, including lower risks of immune reactions and ethical issues. Researchers have recently explored different strategies, such as modifying EVs to enhance their delivery, targeting efficiency, and security, with promising results. This article reviews how MSC-EVs can help treat OA and how they might work. It also briefly discusses the benefits and challenges of using MSC-EVs and talks about the possibility of allogeneic and autologous MSC-EVs for medical use.

Cadmium-induced impairment of spermatozoa development by reducing exosomal-MVBs secretion: a novel pathway

Cadmium is a heavy environmental pollutant that presents a high risk to male-fertility and targets the different cellular and steroidogenic supporting germ cells networks during spermatogenesis. However, the mechanism accounting for its toxicity in multivesicular bodies (MVBs) biogenesis, and exosomal secretion associated with spermatozoa remains obscure. In the current study, the light and electron microscopy revealed that, the Sertoli cells perform a dynamic role with secretion of well-developed early endosomes (Ee) and MVBs pathway associated with spermatozoa during spermatogenesis. In addition, some apical blebs containing nano-scale exosomes located on the cell surface and after fragmentation nano-scale exosomes were directly linked with spermatozoa in the luminal compartment of seminiferous tubules, indicating normal spermatogenesis. Controversially, the cadmium treated group showed limited and deformed spermatozoa with damaging acromion process and mid-peace, and the cytoplasmic vacuolization of spermatids. After cadmium treatment, there is very limited biogenesis of MVBs inside the cytoplasm of Sertoli cells, and no obvious secretions of nano-scale exosomes interacted with spermatozoa. Interestingly, the cadmium treated group demonstrated relatively higher formation of autophagosomes and autolysosome, and the autophagosomes were enveloped by MVBs that later formed the amphisome which degraded by lysosomes, indicating the hypo-spermatogenesis. Moreover, cadmium declined the exosomal protein cluster of differentiation (CD63) and increased the autophagy-related proteins microtubule-associated light chain (LC3), sequestosome 1 (P62) and lysosomal-associated membrane protein 2 (LAMP2) expression level were confirmed by Western blotting. These results provide rich information regarding how cadmium is capable of triggering impaired spermatozoa development during spermatogenesis by reduction of MVBs pathway through high activation of autophagic pathway. This study explores the toxicant effect of cadmium on nano-scale exosomes secretion interacting with spermatozoa.

Exosomes: The role in mammalian reproductive regulation and pregnancy-related diseases

Exosomes are a kind of extracellular vesicles that are produced and secreted by different mammalian cells. They serve as cargo proteins and can transfer different kinds of biomolecules, including proteins, lipids, and nucleic acids, which consequently act on target cells to exert different biological effects. Recent years have witnessed a significant increase in the number of studies on exosomes due to the potential effects of exosomes in the diagnosis and treatment of cancers, neurodegenerative diseases, and immune disorders. Previous studies have demonstrated that exosomal contents, especially miRNAs, are implicated in numerous physiological processes such as reproduction, and are crucial regulators of mammalian reproduction and pregnancy-related diseases. Here, we describe the origin, composition, and intercellular communication of exosomes, and discuss their functions in follicular development, early embryonic development, embryonic implantation, male reproduction and development of pregnancy-related diseases in humans and animals. We believe this study will provide a foundation for revealing the mechanism of exosomes in regulating mammalian reproduction, and providing new approaches and ideas for the diagnosis and treatment of pregnancy-related diseases.

Isolation of extracellular vesicles from bitch's amnion-derived cells culture and their CD59 expression: Preliminary results

Extracellular vesicles (EVs) are small spherical particles surrounded by a membrane with an unusual lipid composition and a striking cholesterol/phospholipidic ratio. About 2000 lipid and 3500 protein species were identified in EVs secreted by different cell sources. EVs mediate cell to cell communication in proximity to or distant from the cell of origin. In particular, it was suggested that they represent modulators of multiple processes during pregnancy. The aim of this study was to identify the presence of EVs in canine amnion-derived cells (ASCs) culture and the expression of CD 59 on their surface. Amniotic membrane was collected in PBS with antibiotics added from 2 bitches during elective caesarean section. Cells culture was prepared and EVs were isolated. EVs were used to evaluate CD59 expression by flow cytofluorimetry. We found that the majority of EVs expressed CD59. Our results could increase the knowledge about the complex mechanisms that regulate the pregnancy in the bitch.

Advances in Purification, Modification, and Application of Extracellular Vesicles for Novel Clinical Treatments

Extracellular vesicles (EV) are membrane vesicles surrounded by a lipid bilayer membrane and include microvesicles, apoptotic bodies, exosomes, and exomeres. Exosome-encapsulated microRNAs (miRNAs) released from cancer cells are involved in the proliferation and metastasis of tumor cells via angiogenesis. On the other hand, mesenchymal stem cell (MSC) therapy, which is being employed in regenerative medicine owing to the ability of MSCs to differentiate into various cells, is due to humoral factors, including messenger RNA (mRNA), miRNAs, proteins, and lipids, which are encapsulated in exosomes derived from transplanted cells. New treatments that advocate cell-free therapy using MSC-derived exosomes will significantly improve clinical practice. Therefore, using highly purified exosomes that perform their original functions is desirable. In this review, we summarized advances in the purification, modification, and application of EVs as novel strategies to treat some diseases.

Molecular Docking and Intracellular Translocation of Extracellular Vesicles for Efficient Drug Delivery

Extracellular vesicles (EVs), including exosomes, mediate intercellular communication by delivering their contents, such as nucleic acids, proteins, and lipids, to distant target cells. EVs play a role in the progression of several diseases. In particular, programmed death-ligand 1 (PD-L1) levels in exosomes are associated with cancer progression. Furthermore, exosomes are being used for new drug-delivery systems by modifying their membrane peptides to promote their intracellular transduction via micropinocytosis. In this review, we aim to show that an efficient drug-delivery system and a useful therapeutic strategy can be established by controlling the molecular docking and intracellular translocation of exosomes. We summarise the mechanisms of molecular docking of exosomes, the biological effects of exosomes transmitted into target cells, and the current state of exosomes as drug delivery systems.