BACKGROUND: Lung cancer currently ranks first globally in both incidence and mortality. Pemetrexed (PMX) serves as a first-line treatment for lung adenocarcinoma (LUAD), but the patients often develop drug resistance during therapy. Milk exosome (mEXO) have the advantages of low immunogenicity, high tissue affinity, and low cost, and mEXO itself has anti-tumor effects. Hyaluronan (HA) naturally bind to CD44, a receptor which is highly expressed in LUAD tissues. This study aims to construct hyaluronan-modified milk exosome (HA-mEXO) and preliminarily investigate their molecular mechanisms for reversing PMX resistance through cellular experiments. METHODS: Exosomes were extracted from milk using high-speed centrifugation, and HA-mEXO was constructed. PMX-resistant A549 and PC-9 cell lines were treated with mEXO and HA-mEXO, respectively. CCK-8 assays, colony formation assays, Transwell assays, and flow cytometry were performed to evaluate proliferation, colony formation, migration, invasion, and apoptosis phenotypes in the treated resistant cell lines. Finally, transcriptomic sequencing, analysis, and cellular functional recovery experiments were conducted to investigate the mechanism by which HA-mEXO reverses PMX resistance in LUAD cells. RESULTS: The expression of CD44 in A549 and PC-9 LUAD drug-resistant cell lines was significantly higher than that in parental cells, and the uptake rate of HA-mEXO by drug-resistant cell lines was significantly higher than that of mEXO. Compared to the mEXO group, HA-mEXO-treated A549 and PC-9 resistant cells exhibited significantly reduced half maximal inhibitory concentration (IC50) values for PMX, markedly diminished clonogenic, migratory, and invasive capabilities, and a significantly increased proportion of apoptotic cells. Western blot analysis revealed that, compared to parental cells, A549 and PC-9 drug-resistant cells exhibited downregulated ZNF516 expression and upregulated ABCC5 expression. Immunofluorescence analysis revealed that HA-mEXO treatment downregulated ABCC5 expression in A549 and PC-9 drug-resistant cells compared to the PBS group, whereas co-treatment with HA-mEXO and ZNF516 knockdown showed no significant change in ABCC5 expression. CONCLUSIONS HA-mEXO carrying ZNF516 suppress ABCC5 expression, thereby enhancing the sensitivity of A549 and PC-9 LAUD drug-resistant cells to PMX.
Humans ; Hyaluronic Acid/chemistry* ; Drug Resistance, Neoplasm/drug effects* ; Exosomes/chemistry* ; Adenocarcinoma of Lung/genetics* ; Pemetrexed/pharmacology* ; Animals ; Lung Neoplasms/pathology* ; Milk/chemistry* ; Cell Proliferation/drug effects* ; Apoptosis/drug effects* ; Cell Line, Tumor ; Hyaluronan Receptors/metabolism*

OBJECTIVE: To investigate the effect of human adipose-derived mesenchymal stem cells (hASCs) exosomes on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) extracted from osteoporotic mice, and to evaluate the effect of hASCs exosomes on preventing bone loss induced by estrogen deficiency. METHODS: hASCs exosomes were extracted by ultracentrifugation. The osteoporotic mice were established by bilateral ovariectomy (OVX). BMSCs were isolated from osteo-porotic mice and cultured for further analysis. In the experimental group, these BMSCs were exposed to an osteogenic induction medium supplemented with hASCs exosomes to evaluate their potential effects on osteogenesis. In contrast, the control group was treated with the same osteogenic induction medium, but without the addition of hASCs exosomes, to serve as a baseline comparison for the study. To comprehensively assess the osteogenic differentiation of BMSCs influenced by hASCs exosomes, alkaline phosphatase (ALP) staining, ALP activity quantitative analysis and quantitative reverse transcription polymerase chain reaction (qPCR) were performed. These evaluations provided critical insights into the role of hASCs exosomes in promoting osteoblast differentiation and bone formation in osteoporotic conditions. The fluorescence labeled hASCs exosomes were injected via the tail vein to observe the biodistribution of exosomes. Two weeks after OVX, the mice were divided into three groups: The experimental group consisted of estrogen-deficient mice receiving hASCs exosome injections; the negative control group consisted of estrogen-deficient mice receiving phosphate-buffered saline (PBS) injections; and the positive control group consisted of mice that underwent Sham surgery and received PBS injections.The injections were administered once every 3 days, for a total of 8 injections. Afterward, the femurs were collected from the mice, and micro-computed tomography (micro-CT) was performed to measure bone mineral density and conduct bone morphometric analysis. RESULTS: hASCs exosomes were successfully extracted using ultracentrifugation. After the induction by hASCs exosomes, ALP staining and ALP activity in the BMSCs extracted from osteoporotic mice were significantly enhanced, the expression of osteogenesis related genes in BMSCs were significantly up-regulated. More trabecular bone and higher bone mineral density were observed in estrogen-deficient mice injected with hASCs exosomes compared with estrogen-deficient mice injected with PBS, and there was no significant decrease in bone mineral density compared with the Sham operation group. CONCLUSION hASCs exosomes promoted the osteogenic differentiation of BMSCs extracted from osteoporotic mice. hASCs exosomes prevented bone loss induced by estrogen deficiency.
Animals ; Mesenchymal Stem Cells/cytology* ; Exosomes ; Estrogens/deficiency* ; Humans ; Osteogenesis ; Cell Differentiation ; Female ; Mice ; Osteoporosis/prevention & control* ; Ovariectomy ; Adipose Tissue/cytology* ; Cells, Cultured

OBJECTIVE: To investigate the effect of zedoarondiol on neovascularization of atherosclerotic (AS) plaque by exosomes experiment. METHODS: ApoE^-/- mice were fed with high-fat diet to establish AS model and treated with high- and low-dose (10, 5 mg/kg daily) of zedoarondiol, respectively. After 14 weeks, the expressions of anti-angiogenic protein thrombospondin 1 (THBS-1) and its receptor CD36 in plaques, as well as platelet activation rate and exosome-derived miR-let-7a were detected. Then, zedoarondiol was used to intervene in platelets in vitro, and miR-let-7a was detected in platelet-derived exosomes (Pexo). Finally, human umbilical vein endothelial cells (HUVECs) were transfected with miR-let-7a mimics and treated with Pexo to observe the effect of miR-let-7a in Pexo on tube formation. RESULTS: Animal experiments showed that after treating with zedoarondiol, the neovascularization density in plaques of AS mice was significantly reduced, THBS-1 and CD36 increased, the platelet activation rate was markedly reduced, and the miR-let-7a level in Pexo was reduced (P<0.01). In vitro experiments, the platelet activation rate and miR-let-7a levels in Pexo were significantly reduced after zedoarondiol's intervention. Cell experiments showed that after Pexo's intervention, the tube length increased, and the transfection of miR-let-7a minics further increased the tube length of cells, while reducing the expressions of THBS-1 and CD36. CONCLUSION Zedoarondiol has the effect of inhibiting neovascularization within plaque in AS mice, and its mechanism may be potentially related to inhibiting platelet activation and reducing the Pexo-derived miRNA-let-7a level.
Animals ; MicroRNAs/genetics* ; Exosomes/drug effects* ; Plaque, Atherosclerotic/genetics* ; Neovascularization, Pathologic/genetics* ; Human Umbilical Vein Endothelial Cells/metabolism* ; Humans ; Blood Platelets/drug effects* ; Apolipoproteins E/deficiency* ; Thrombospondin 1/metabolism* ; CD36 Antigens/metabolism* ; Platelet Activation/drug effects* ; Male ; Mice ; Mice, Inbred C57BL

Exosomes are small vesicles commonly found in bodily fluids such as blood, urine, ascites, and breast milk. As essential mediators of intercellular communication, exosomes play pivotal roles in physiological and pathological processes including material transport, signal transduction, homeostasis regulation, immune response, and angiogenesis. They are promising biomarkers for disease diagnosis and key carriers for therapeutic drug delivery. Longitudinal tracking of exosome biodistribution, elucidating their migratory routes and homing effects, determining optimal delivery routes and therapeutic dosages, and evaluating implantation in target tissues are crucial for better understanding their mechanisms of action and guiding clinical applications. Magnetic resonance imaging (MRI), as a non-invasive and repeatable imaging technique, offers an ideal approach for exosome tracking. By labeling exosomes with specific contrast agents or tracers and detecting them via MRI, researchers can trace exosomes in vivo. This facilitates advancements in exosome-based nanomedicine and accelerates the clinical translation of exosome diagnostics and therapeutics.
Exosomes/metabolism* ; Humans ; Magnetic Resonance Imaging/methods* ; Contrast Media ; Animals ; Tissue Distribution

OBJECTIVES: Neurodegenerative diseases are closely associated with myelin loss, and the proliferation and differentiation of oligodendrocyte precursor cells (OPCs) are crucial to remyelination. However, the regulatory mechanisms involved remain incompletely understood. This study aims to investigate how astrocytes (ASTs) regulate the secretion of chitinase-3-like protein 1 (CHI3L1) via connexin 47 (Cx47)-mediated exosome signaling, and its subsequent effect on OPC proliferation. METHODS: Primary cells were isolated from postnatal day 1 Sprague-Dawley (P1SD) rats to establish 3 culture conditions: OPCs alone (Group O), OPCs in direct contact with ASTs (Group C), and OPCs cultured with AST-conditioned medium (Group A). Cellular morphology and proliferation were assessed using optical microscopy, 5-ethynyl-2'- deoxyuridine (EdU) incorporation, and flow cytometry. RNA sequencing (RNA-Seq) and bioinformatics analysis (BA) were conducted to identify differentially expressed genes (DEGs) among groups. Protein expression and cell cycle distribution were analyzed by Western blotting (WB) and flow cytometry. Exosomes were isolated and purified via differential centrifugation, characterized by nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM), and CHI3L1 expression in exosomes was verified via WB. Cx47 was silenced using small interfering RNA (siRNA) to evaluate its effect on OPC proliferation and exosome secretion. Artificial exosomes were constructed by encapsulating CHI3L1 in single unilamellar vesicles (SUVs), whose structure and size were validated by NTA and TEM. Following Cx47 knockdown, artificial exosomes were added back, and OPC proliferation was assessed via flow cytometry and EdU assay. RESULTS: Direct co-cultured with ASTs (Group C) resulted in significantly enhanced OPC proliferation compared to the Group O and Group A (P<0.05). RNA-Seq and WB analyses revealed that ASTs promote OPC proliferation and exosome secretion enriched in CHI3L1 through Cx47. Cx47 knockdown by siRNA led to significant decreases in OPC proliferation and exosome release (P<0.05). The inhibitory effect of Cx47 silencing on OPC proliferation was partially reversed by supplementation with either isolated exosomes or exogenous CHI3L1. CONCLUSIONS This study reveals a novel mechanism by which ASTs regulate OPC proliferation: Through direct contact, ASTs enhance the secretion of CHI3L1-rich exosomes via Cx47, thereby converting intercellular contact signals into secretory signals that promote OPC proliferation. As a key exosomal molecule, CHI3L1 may play an important role in neural function and remyelination and warrants further investigation.
Animals ; Exosomes/metabolism* ; Cell Proliferation ; Rats, Sprague-Dawley ; Rats ; Connexins/genetics* ; Oligodendrocyte Precursor Cells/metabolism* ; Astrocytes/metabolism* ; Chitinase-3-Like Protein 1/metabolism* ; Cells, Cultured ; Cell Differentiation

Cardiovascular disease (CVD) poses a serious threat to human health. Exercise plays an important role in both the prevention and treatment of CVD and is one of the key non-pharmacological interventions. Exercise can regulate the level of exerkine secreted by different tissue cells, directly affect the cardiovascular system or play a role in cardiovascular protection by improving cardiovascular risk factors. Exerkine such as meteorin-like protein (Metrnl), brain-derived neurotrophic factor (BDNF), fibroblast growth factor 21 (FGF21), and exosomal microRNA (miRNA) play an important role in regulating vascular and cardiac diseases such as atherosclerosis, heart failure, cardiac ischemia-reperfusion and myocardial infarction, as well as their risk factors. Exploring the signaling pathways and mechanisms by which Metrnl, BDNF, FGF21, and exosomal miRNAs exert cardiovascular protective effects can provide novel insights into exercise-based strategies for preventing and treating cardiovascular diseases.
Humans ; Cardiovascular Diseases/prevention & control* ; Exercise/physiology* ; Fibroblast Growth Factors/physiology* ; MicroRNAs/metabolism* ; Brain-Derived Neurotrophic Factor/physiology* ; Cardiovascular System/physiopathology* ; Exosomes/metabolism* ; Signal Transduction

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a severe critical condition marked by rapid progression and high fatality. It results from direct/indirect lung-related or systemic triggers, leading to widespread injury of lung epithelial and endothelial cells. Its pathogenesis involves uncontrolled inflammation and breakdown of the lung's blood-air barrier due to leaky blood vessels and epithelial damage. Current management of ALI/ARDS remains primarily supportive, offering symptomatic relief but limited improvement in prognosis, necessitating deeper exploration of upstream pathogenic mechanisms to identify safer and more effective therapies. Exosomal microRNAs (miRNA), small extracellular vesicles (40-150 nm) containing non-coding single-stranded RNAs, regulate post-transcriptional cellular processes and participate in ALI/ARDS pathophysiology. Studies reveal that exosomes transport proteins, nucleic acids, and miRNAs to recipient cells, mediating intercellular communication. In ALI/ARDS models, exosomal miRNAs delivered to alveolar epithelial cells, endothelial cells, macrophages, and neutrophils critically modulate autophagy, pyroptosis, apoptosis, proliferation, inflammatory signaling, macrophage polarization, and neutrophil activation, either exacerbating or alleviating disease progression. Recent advances in engineering techniques have enhanced the therapeutic potential of exosomal miRNAs by overcoming limitations of natural exosomes. This review focuses on exosomal miRNA-mediated regulation of ALI/ARDS pathogenesis across key cell types, providing insights for novel therapeutic strategies.
Exosomes ; Humans ; MicroRNAs ; Acute Lung Injury ; Respiratory Distress Syndrome ; Animals

OBJECTIVE: To reveal the effects and potential mechanisms by which synaptic vesicle glycoprotein 2A (SV2A) influences the distribution of amyloid precursor protein (APP) in the trans-Golgi network (TGN), endolysosomal system, and cell membranes and to reveal the effects of SV2A on APP amyloid degradation. METHODS: Colocalization analysis of APP with specific tagged proteins in the TGN, ensolysosomal system, and cell membrane was performed to explore the effects of SV2A on the intracellular transport of APP. APP, β-site amyloid precursor protein cleaving enzyme 1 (BACE1) expressions, and APP cleavage products levels were investigated to observe the effects of SV2A on APP amyloidogenic processing. RESULTS: APP localization was reduced in the TGN, early endosomes, late endosomes, and lysosomes, whereas it was increased in the recycling endosomes and cell membrane of SV2A-overexpressed neurons. Moreover, Arl5b (ADP-ribosylation factor 5b), a protein responsible for transporting APP from the TGN to early endosomes, was upregulated by SV2A. SV2A overexpression also decreased APP transport from the cell membrane to early endosomes by downregulating APP endocytosis. In addition, products of APP amyloid degradation, including sAPPβ, Aβ _1-42, and Aβ _1-40, were decreased in SV2A-overexpressed cells. CONCLUSION These results demonstrated that SV2A promotes APP transport from the TGN to early endosomes by upregulating Arl5b and promoting APP transport from early endosomes to recycling endosomes-cell membrane pathway, which slows APP amyloid degradation.
Amyloid beta-Protein Precursor/genetics* ; Membrane Glycoproteins/genetics* ; Animals ; Protein Transport ; Nerve Tissue Proteins/genetics* ; Humans ; Mice ; Endosomes/metabolism* ; trans-Golgi Network/metabolism*

Chronic non-healing wounds significantly impair patient rehabilitation and remain a critical clinical challenge. Stem cell-derived exosomes, owing to their biocompatibility and physiological activity, have emerged as a promising therapeutic approach in regenerative medicine. Beyond their intrinsic wound-healing properties, exosomes are increasingly explored as carriers for small-molecule drugs to enhance synergistic treatment effects. Although microRNAs (miRNAs) exhibit potential in promoting cell proliferation and re-epithelialization, their clinical application is hindered by poor stability. In this study, we investigated the therapeutic effects of miR-132-3p-loaded human umbilical mesenchymal stem cell-derived exosomes (miR-132-3p@UMSC-EXOs) on human foreskin fibroblast-1 (HFF-1). Our findings demonstrated that miR-132-3p@UMSC-EXOs significantly enhanced proliferation and migration of HFF-1, while reducing intracellular reactive oxygen species (ROS) levels compared with unloaded exosomes. Furthermore, qRT-PCR and Western blotting analyses revealed that miR-132-3p@UMSC-EXOs modulated the expression of genes associated with extracellular matrix (ECM) remodeling and inflammation, suggesting their potential to upregulate collagen synthesis and improve ECM metabolism. These results highlight the therapeutic promise of miR-132-3p@UMSC-EXOs in accelerating wound healing.
Humans ; MicroRNAs/pharmacology* ; Exosomes/metabolism* ; Mesenchymal Stem Cells/cytology* ; Wound Healing ; Umbilical Cord/cytology* ; Cell Proliferation ; Fibroblasts/cytology* ; Skin/injuries* ; Cell Movement ; Reactive Oxygen Species/metabolism* ; Cells, Cultured

Obstructive sleep apnea (OSA) is a global public health concern characterized by repeated upper airway collapse during sleep. Research indicates that OSA is a risk factor for the development of various diseases, including cardiovascular disease, metabolic disorders, respiratory diseases, neurodegenerative diseases, and cancer. Exosomes, extracellular vesicles released by most cell types, play a key role in intercellular communication by transporting their contents-such as microRNA, messenger RNA, DNA, proteins, and lipids-to target cells. Intermittent hypoxia associated with OSA alters circulating exosomes and promotes a range of cellular structural and functional disturbances involved in the pathogenesis of OSA-related diseases. This review discusses the potential roles of exosomes and exosome-derived molecules in the onset and progression of OSA-associated diseases, explores the possible underlying mechanisms, and highlights novel strategies for developing exosome-based therapies for these conditions.
Humans ; Exosomes/physiology* ; Sleep Apnea, Obstructive/metabolism* ; Animals ; MicroRNAs/metabolism*