Exosome-Transmitted miR-224-5p Promotes Colorectal Cancer Cell Proliferation via Targeting ULK2 in p53-Dependent Manner / 生物医学与环境科学（英文）

OBJECTIVE@#To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer (CRC).@*METHODS@#The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser capture microdissection and qRT-PCR, respectively. Dual-luciferase reporter gene assay was used to determine the target gene of miR-224-5p. The protein expressions of p53 and unc-51 like kinase 2 (ULK2) in CRC cells were detected by western blot. Flow cytometry was used to detect cell cycle and apoptosis. Cell proliferation was measured by CCK8 and EdU assay.@*RESULTS@#The miR-224-5p expression was upregulated in CRC tissues and increased progressively with the rise of CRC stage. CRC cells secreted extracellular miR-224-5p mainly in an exosome-dependent manner, and then miR-224-5p could be transferred to surrounding tumor cells to regulate cell proliferation in the form of autocrine or paracrine. Moreover, ULK2 was characterized as a direct target of miR-224-5p and was downregulated in CRC tissues. Interestingly, ULK2 inhibited CRC cell proliferation in a p53-dependent manner. Furthermore, exosome-derived miR-224-5p partially reversed the proliferation regulation of ULK2 on CRC cells.@*CONCLUSION@#Our findings demonstrate that exosome-transmitted miR-224-5p promotes p53-dependent cell proliferation by targeting ULK2 in CRC, which may offer promising targets for CRC prevention and therapy.

MSC-derived exosomes protect auditory hair cells from neomycin-induced damage via autophagy regulation

BACKGROUND: Sensorineural hearing loss (SNHL) poses a major threat to both physical and mental health; however, there is still a lack of effective drugs to treat the disease. Recently, novel biological therapies, such as mesenchymal stem cells (MSCs) and their products, namely, exosomes, are showing promising therapeutic potential due to their low immunogenicity, few ethical concerns, and easy accessibility. Nevertheless, the precise mechanisms underlying the therapeutic effects of MSC-derived exosomes remain unclear. RESULTS: Exosomes derived from MSCs reduced hearing and hair cell loss caused by neomycin-induced damage in models in vivo and in vitro. In addition, MSC-derived exosomes modulated autophagy in hair cells to exert a protective effect. Mechanistically, exogenously administered exosomes were internalized by hair cells and subsequently upregulated endocytic gene expression and endosome formation, ultimately leading to autophagy activation. This increased autophagic activity promoted cell survival, decreased the mitochondrial oxidative stress level and the apoptosis rate in hair cells, and ameliorated neomycin-induced ototoxicity. CONCLUSIONS: In summary, our findings reveal the otoprotective capacity of exogenous exosome-mediated autophagy activation in hair cells in an endocytosis-dependent manner, suggesting possibilities for deafness treatment.

Treatment of intrauterine adhesions in rats with hypoxia-cultured BMSC-derived exosomes / 中华妇产科杂志

Objective: To perform intrauterine adhesion modeling, and to investigate the repair effect of hypoxic treated bone marrow mesenchymal stem cells (BMSC) and their derived exosomes (BMSC-exo) on endometrial injury. Methods: BMSC and their exosomes BMSC-exo extracted from rats' femur were cultured under conventional oxygen condition (21%O2) or hypoxia condition (1%O2). Intrauterine adhesion modeling was performed on 40 healthy female SD rats by intrauterine injection of bacterial lipopolysaccharide after curettage. On the 28th day of modeling, 40 rat models were randomly divided into five groups, and interventions were performed: (1) NC group: 0.2 ml phosphate buffered solution was injected into each uterine cavity; (2) BMSC group: 0.2 ml BMSC (1×106/ml) with conventional oxygen culture was injected intrauterine; (3) L-BMSC group: 0.2 ml of hypoxic cultured BMSC (1×106/ml) was injected intrauterine; (4) BMSC-exo group: 0.2 ml of BMSC-exo cultured with conventional oxygen at a concentration of 500 μg/ml was injected into the uterine cavity; (5) L-BMSC-exo group: 0.2 ml hypoxic cultured BMSC-exo (500 μg/ml) was injected intrauterine. On the 14th and 28th day of treatment, four rats in each group were sacrificed by cervical dislocation after anesthesia, and endometrial tissues were collected. Then HE and Masson staining were used to observe and calculate the number of glands and fibrosis area in the endometrium. The expressions of angiogenesis related cytokines [vascular endothelial growth factor A (VEGFA) and CD31], and fibrosis-related proteins [collagen-Ⅰ, collagen-Ⅲ, smooth muscle actin α (α-SMA), and transforming growth factor β1 (TGF-β1)] in endometrial tissues were detected by western blot. Results: (1) HE and Masson staining showed that the number of endometrial glands in L-BMSC group, BMSC-exo group and L-BMSC-exo group increased and the fibrosis area decreased compared with NC group on the 14th and 28th day of treatment (all P<0.05). Noteworthily, the changes of L-BMSC-exo group were more significant than those of BMSC-exo group (all P<0.05), and the changes of BMSC-exo group were greater than those of BMSC group (all P<0.05). (2) Western blot analysis showed that, compared with NC group, the expressions of collagen-Ⅲ and TGF-β1 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group decreased on the 14th and 28th day of treatment (all P<0.05). As the treatment time went on, the expressions of fibrosis-related proteins were different. Compared with BMSC group, the expressions of collagen-Ⅲ, α-SMA and TGF-β1 in the BMSC-exo group and L-BMSC group decreased on the 28th day (all P<0.05). Moreover, the expressions of collagen-Ⅲ and TGF-β1 in L-BMSC-exo group were lower than those in BMSC-exo group on the 28th day (all P<0.05). And the expressions of collagen-Ⅰ, α-SMA and TGF-β1 in L-BMSC-exo group were lower than those in L-BMSC group on the 28th day (all P<0.05). (3) The results of western blot analysis of VEGFA and CD31 showed that, the expressions of VEGFA and CD31 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group increased on the 14th and 28th day of treatment compared with NC group (all P<0.05). Treatment for 28 days, the expressions of VEGFA and CD31 in BMSC-exo group and CD31 in L-BMSC group were higher than those in BMSC group (all P<0.05). Moreover, the expressions of VEGFA and CD31 in L-BMSC-exo group were higher than those in BMSC-exo group and L-BMSC group on the 28th day (all P<0.05). Conclusions: Treatment of BMSC and their exosomes BMSC-exo with hypoxia could promote endometrial gland hyperplasia, inhibit tissue fibrosis, and further repair the damaged endometrium in rats with intrauterine adhesion. Importantly, hypoxic treatment of BMSC-exo is the most effective in intrauterine adhesion rats.

Research progress on the mechanism of exosomes in bacterial infectious diseases / 中华危重病急救医学

Bacterial infectious diseases are a class of diseases with specific pathogens. Current studies have shown the important application and signal transduction mechanism of exosomes in bacterial infectious diseases, but the studies are still limited. Therefore, the relationship between exosomes and bacterial infectious diseases should be further explored to provide new diagnosis and treatment ideas for clinicians. This paper reviews the mechanism and prospect of exosomes in bacterial infectious diseases caused by different pathogens. It summarizes the biological characteristics of exosomes. The mechanisms of bacterial infectious diseases, the primary pathways through which exosomes regulate various pathogens, and the modification of exosomes for anti-infection.

Research progress of exosomes in the diagnosis and treatment of sepsis / 中华危重病急救医学

Sepsis is a life-threatening organ dysfunction caused by infection that lead to dysregulation of the host response. Sepsis and septic shock with a high mortality threaten human health at present, which are important medical and health problems. Early diagnosis and treatment decision-making for sepsis and septic shock still need to be improved. Exosomes are extracellular vesicles with a diameter of 30-150 nm formed by the fusion of multi-vesicle bodies and cell membranes. Exosomes can effectively transport a variety of bioactive substances such as proteins, lipids, RNA, DNA, and participate in the regulation of inflammatory response, immune response, infection and other pathophysiological processes. In recent years, exosomes have become one of the important methods for the diagnosis and treatment of systemic inflammatory diseases. This article will focus on the basic and clinical research of sepsis, and focus on the research progress of exosomes in the diagnosis and targeted therapy of sepsis.

SHED-derived exosomes ameliorate hyposalivation caused by Sjögren's syndrome via Akt/GSK-3β/Slug-mediated ZO-1 expression / 中华医学杂志(英文版)

BACKGROUND@#Sjögren's syndrome (SS) is an autoimmune disorder characterized by sicca syndrome and/or systemic manifestations. The treatment is still challenging. This study aimed to explore the therapeutic role and mechanism of exosomes obtained from the supernatant of stem cells derived from human exfoliated deciduous teeth (SHED-exos) in sialadenitis caused by SS.@*METHODS@#SHED-exos were administered to the submandibular glands (SMGs) of 14-week-old non-obese diabetic (NOD) mice, an animal model of the clinical phase of SS, by local injection or intraductal infusion. The saliva flow rate was measured after pilocarpine intraperitoneal injection in 21-week-old NOD mice. Protein expression was examined by western blot analysis. Exosomal microRNA (miRNAs) were identified by microarray analysis. Paracellular permeability was evaluated by transepithelial electrical resistance measurement.@*RESULTS@#SHED-exos were injected into the SMG of NOD mice and increased saliva secretion. The injected SHED-exos were taken up by glandular epithelial cells, and further increased paracellular permeability mediated by zonula occluden-1 (ZO-1). A total of 180 exosomal miRNAs were identified from SHED-exos, and Kyoto Encyclopedia of Genes and Genomes analysis suggested that the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) pathway might play an important role. SHED-exos treatment down-regulated phospho-Akt (p-Akt)/Akt, phospho-glycogen synthase kinase 3β (p-GSK-3β)/GSK-3β, and Slug expressions and up-regulated ZO-1 expression in SMGs and SMG-C6 cells. Both the increased ZO-1 expression and paracellular permeability induced by SHED-exos were abolished by insulin-like growth factor 1, a PI3K agonist. Slug bound to the ZO-1 promoter and suppressed its expression. For safer and more effective clinical application, SHED-exos were intraductally infused into the SMGs of NOD mice, and saliva secretion was increased and accompanied by decreased levels of p-Akt/Akt, p-GSK-3β/GSK-3β, and Slug and increased ZO-1 expression.@*CONCLUSION@#Local application of SHED-exos in SMGs can ameliorate Sjögren syndrome-induced hyposalivation by increasing the paracellular permeability of glandular epithelial cells through Akt/GSK-3β/Slug pathway-mediated ZO-1 expression.

Functionalized exosome-loaded ginsenoside Rg1 for the treatment of ischemic stroke / 生物工程学报

The aim of this study was to investigate the therapeutic effects and potential mechanism of c(RGDyK) peptide modified mesenchymal stem cell exosomes loaded with ginsenoside Rg1 (G-Rg1) on ischemic stroke. Thread-tying method was used to establish SD rats transient middle cerebral occlusion model (tMCAO). The model rats were randomly divided into tMCAO group, Exo group, free G-Rg1 group, Exo-Rg1 group and cRGD-Exo-Rg1 group, and sham group was used as control. The infarct volume was measured by 2, 3, 5-triphenyltetrachloride (TTC) staining, the changes of neuron and endothelium were observed by immunofluorescence, and the expression of related proteins was detected by Western blotting. The results showed that cRGD-Exo-Rg1 up-regulated the expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factors (HIF-1α) by activating PI3K/AKT pathway, thus promoting angiogenesis and neurogenesis, effectively reducing the volume of cerebral infarction and improving neural function. In addition, the delivery of cRGD-Exo-Rg1 to ischemic brain tissue up-regulated the expression of occludin and claudin-5, and reduced the injury of blood-brain barrier. Taken together, cRGD-Exo-Rg1 was effective in the treatment of ischemic stroke by promoting angiogenesis and neurogenesis, which provided experimental evidence for the potential clinical benefits of other neuroprotective therapies.

Research progress on plant-derived exosome-like nanoparticles and their applications / 中国中药杂志

Plant-derived exosome-like nanoparticles(PELNs) are a class of membranous vesicles with diameters approximately ranging from 30 to 300 nm, isolated from plant tissues. They contain components such as proteins, lipids, and nucleic acids. PELNs play an important role in the metabolism of plant substances and immune defense, and can also cross-regulate the physiological activities of fungi and animal cells, showing significant potential applications. In recent years, research on PELNs has significantly increased, highlighting three main issues:(1) the mixed sources of plant materials for PELNs;(2) the lack of a unified system for isolating and characterizing PELNs;(3) the urgent need to elucidate the molecular mechanisms underlying the cross-regulation of biological functions by PELNs. This article focused on these concerns. It began by summarizing the biological origin and composition of PELNs, discussing the techniques for isolating and characterizing PELNs, and analyzing their biomedical applications and potential future research directions., aiming to promote the establishment of standardized research protocols for PELNs and provide theoretical references for in-depth exploration of the mechanisms underlying PELNs' cross-regulatory effects.

Expression and Clinical Significance of Exosome Derived MiR-181b-5p in Children with Acute Lymphoblastic Leukemia / 中国实验血液学杂志

OBJECTIVE@#To explore the expression level of exosome derived miR-181b-5p in different disease stages of children with acute lymphoblastic leukemia and its relationship with clinical characteristics.@*METHODS@#Bone marrow plasma samples of 86 children with ALL were collected. Exosomes were extracted by exosome extraction kit, and RNA in exosomes was extracted by TRIzol method. The levels of miR-181b-5p in the blood plasma exosomes of the patients in the newly diagnosed group, relapse group, remission group and control group were detected by qRT- PCR. The difference of miR-181b-5p expression level in each group was compared and analyzed, and the relationship between miR-181b-5p expression level and clinical characteristics was analyzed.@*RESULTS@#The expression level of exosomal miR-181b-5p in the newly diagnosed group and the relapsed group was significantly lower than that in the remission group and the control group (P< 0.05). The expression level of exosomal miR-181b-5p in T-ALL children was higher than that in B-ALL children (P<0.05). The expression level of plasma exosomal miR-181b-5p in male children was higher than that in female children (P<0.01).@*CONCLUSION@#Exosome derived miR-181b-5p changes dynamically in the course of ALL children, and can be used as a marker miRNA to monitor disease status. Exosomes can transmit information in the tumor microenvironment and serve as a potential carrier for biomolecular targeted therapy.

Testicular exosomes disturb the immunosuppressive phenotype of testicular macrophages mediated by miR-155-5p in uropathogenic Escherichia coli-induced orchitis / 亚洲男科学杂志(英文版)

Male reproductive infections are known to shape the immunological homeostasis of the testes, leading to male infertility. However, the specific pathogenesis of these changes remains poorly understood. Exosomes released in the inflammatory microenvironment are important in communication between the local microenvironment and recipient cells. Here, we aim to identify the immunomodulatory properties of inflammatory testes-derived exosomes (IT-exos) and explore their underlying mechanisms in orchitis. IT-exos were isolated using a uropathogenic Escherichia coli (UPEC)-induced orchitis model and confirmed that IT-exos promoted proinflammatory M1 activation with increasing expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in vitro. We further used small RNA sequencing to identify the differential miRNA profiles in exosomes and primary testicular macrophages (TMs) from normal and UPEC-infected testes, respectively, and identified that miR-155-5p was highly enriched in IT-exos and TMs from inflammatory testes. Further study of bone marrow derived macrophages (BMDMs) transfected with miR-155-5p mimic showed that macrophages polarized to proinflammatory phenotype. In addition, the mice that were administrated IT-exos showed remarkable activation of TM1-like macrophages; however, IT-exos with silencing miR-155-5p showed a decrease in proinflammatory responses. Overall, we demonstrate that miR-155-5p delivered by IT-exos plays an important role in the activation of TM1 in UPEC-induced orchitis. Our study provides a new perspective on the immunological mechanisms underlying inflammation-related male infertility.

Viral myocarditis serum exosome-derived miR-320 promotes the apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway and targeting phosphatidylinositol 3-kinase regulatory subunit 1 (Pik3r1) / 细胞与分子免疫学杂志

Objective To investigate the effect of viral myocarditis serum exosomal miR-320 on apoptosis of cardiomyocytes and its mechanism. Methods The model of viral myocarditis mice was established by intraperitoneal injection of Coxsackie virus B3. Serum exosomes were extracted by serum exosome extraction kit and co-cultured with cardiomyocytes. The uptake of exosomes by cardiomyocytes was detected by laser confocal microscopy. Cardiomyocytes were transfected with miR-320 inhibitor or mimic, and the expression level of miR-320 was detected by real-time quantitative PCR. Flow cytometry was used to detect cardiomyocyte apoptosis rate, and the expression levels of B cell lymphoma 2 (Bcl2) and Bcl2-related X protein (BAX) were tested by Western blot analysis. The prediction of miR-320 target genes and GO and KEGG enrichment analysis were tested by online database. The relationship between miR-320 and its target gene phosphoinositide-3-kinase regulatory subunit 1(Pik3r1) was examined by luciferase reporter gene. The effect of miR-320 on AKT/mTOR pathway protein was detected by Western blot analysis. Results Viral myocarditis serum exosomes promoted cardiomyocyte apoptosis, and increased the level of BAX while the level of Bcl2 was decreased. miR-320 was significantly up-regulated in myocardial tissue of viral myocarditis mice, and both pri-miR-320 and mature of miR-320 were up-regulated greatly in cardiomyocytes. The level of miR-320 in cardiomyocytes treated with viral myocarditis serum exosomes was significantly up-regulated, while transfection of miR-320 inhibitor counteracted miR-320 overexpression and reduced apoptosis rate caused by exosomes. Pik3r1 is the target gene of miR-320, and its overexpression reversed cardiomyocyte apoptosis induced by miR-320 up-regulation. The overexpression of miR-320 inhibited AKT/mTOR pathway activation. Conclusion Viral myocarditis serum exosome-derived miR-320 promotes apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway by targeting Pik3r1.

miR-30e-3p in natural killer cell-derived exosomes inhibits the proliferation and invasion of human esophageal squamous carcinoma cells / 细胞与分子免疫学杂志

Objective To investigate the effects of natural killer (NK)-cell-derived miR-30e-3p-containing exosomes (Exo) on esophageal squamous cell carcinoma (ESCC) cell proliferation, apoptosis and invasion. Methods NK cells were isolated and amplified from the peripheral blood of healthy donors, and NK cell-derived Exo was isolated and identified, which were further co-cultured with NEC cells and were randomly grouped into Exo1 and Exo2 groups. Transmission electron microscopy (TEM) was used to observe the morphology and size of exosomes. Western blot analysis was used to detect the expression levels of exosome markers apoptosis related gene 2- interacting protein X(ALIX), tumor susceptibility gene 101(TSG101), CD81 and calnexin. The NC plasmids, mimics and inhibitors of miR030e-3p were respectively delivered into the NK cells, and the corresponding NK cells-derived Exo were co-cultured with NEC cells, which were divided into NC, Exo, mimic and inhibitor groups. CCK-8 assay was used to evaluate cell proliferation, flow cytometry was conducted to determine cell cycle, annexin V-FITC/PI double staining was employed to detect cell apoptosis, and TranswellTM assay was performed to detect cell invasion abilities. Real-time quantitative PCR was used to detect the expression of miR-23b, miR-422a, miR-133b, miR-124, miR-30e-3p and miR-99a in NCE cells and exosomes. Results The percentages of CD56+CD3+ cells and CD56+CD16+ cells in NK cells were (0.071±0.008)% and (90.6±10.6)%, respectively. Exosome isolated from NK cells ranged from 30 nm to 150 nm, and was positive for ALIX, TSG101 and CD81, while negative for calnexin. NK cell-derived Exos inhibited the proliferation, reduced the proportion of S-phase cells and the number of invaded cells of NEC cells, and promoted the apoptosis and the proportion of G1 phase cells. Overexpression of miR-30E-3p in NK cell-derived exosome inhibited the proliferation and invasion of NEC cells, and blocked cell cycle and promoted apoptosis, while knockdown miR-30e-3p in NK cell-derived exosomes did the opposite. Conclusion miR-30e-3p in NK cell-derived exosomes can inhibit the proliferation and invasion of ESCC cells, block their cell cycle and induce their apoptosis.

Effect of circulating exosomes in patients with sepsis on T cell function / 中华危重病急救医学

OBJECTIVE@#To investigate the effect of circulating exosomes (EXO) on T cell function in patients with sepsis.@*METHODS@#Plasma EXO were obtained by ultracentrifugation from 10 patients with sepsis admitted to the emergency intensive care unit of Guangdong Provincial People's Hospital Affiliated to Southern Medical University. Transmission electron microscopy observation, nanoparticle tracking analysis (NTA), and Western blotting were used to detect EXO markers to identify their characteristics. Furthermore, peripheral blood mononuclear cells (PBMC) were isolated from the peripheral blood of 5 healthy volunteers, primary T cells were sorted by magnetic beads and expanded in vitro. After 24 hours of intervention with different doses (0, 1, 2.5, 5, 10 mg/L) of circulating EXO in patients with sepsis, T-cell activity was assessed using a cell counting kit-8 (CCK-8). The expression of T cell activation indicators CD69 and CD25 were observed using flow cytometry. Additional evaluations were performed on immunosuppressive indicators including the expression of programmed cell death 1 (PD-1) in CD4+ T cells and the proportion of regulatory T cell (Treg).@*RESULTS@#The identification results confirmed that the successful isolation of EXO from the plasma of sepsis patients. The expression level of circulating EXO in sepsis patients was higher than that in healthy control group (mg/L: 48.78±5.14 vs. 22.18±2.25, P < 0.01). After 24 hours of intervention with 5 mg/L of plasma EXO from sepsis patients, T cells activity began to show suppression [(85.84±0.56)% vs. (100.00±0.00)%, P < 0.05]. As the dosage increased, after 24 hours of intervention with 10 mg/L of EXO, T cells activity was significantly suppressed [(72.44±2.36)% vs. (100.00±0.00)%, P < 0.01]. Compared with the healthy control group, after T cells intervention with plasma EXO from sepsis patients, the expression of early activation marker CD69 was significantly reduced [(52.87±1.29)% vs. (67.13±3.56)%, P < 0.05]. Meanwhile, there was an upregulation of PD-1 expression in T cells [(57.73±3.06)% vs. (32.07±0.22)%, P < 0.01] and an increase in the proportion of Treg [(54.67±1.19)% vs. (24.60±3.51)%, P < 0.01]. However, the expression of the late activation marker CD25 remained stable [(84.77±3.44)% vs. (85.93±2.32)%, P > 0.05].@*CONCLUSIONS@#Circulating EXO in sepsis patients induce T cell dysfunction, which may be a novel mechanism lead to immunosuppression in sepsis.

Effect of exosomes as drug carriers in chemotherapy of pancreatic cancer / 中南大学学报(医学版)

Pancreatic cancer (PC) is a malignant tumor of the digestive tract with poor patient prognosis. The PC incidence is still increasing with a 5-year survival rate of only 10%. At present, surgical resection is the most effective method to treat PC, however, 80% of the patients missed the best time for surgery after they have been diagnosed as PC. Chemotherapy is one of the main treating methods but PC is insensitive to chemotherapy, prone to drug resistance, and is accompanied by many side effects which are related to a lack of specific target. Exosomes are nanoscale vesicles secreted by almost all cell types and can carry various bioactive substances which mediate cell communication and material transport. They are characterized by a low immunogenicity, low cytotoxicity, high penetration potential and homing capacity, and possess the potential of being used as advanced drug carriers. Therefore, it is a hot research topic to use drug-loaded exosomes for tumor therapy. They may alleviate chemotherapy resistance, reduce side effects, and enhance the curative effect. In recent years, exosome drug carriers have achieved considerable results in PC chemotherapy studies.

Danhong Injection Up-regulates miR-125b in Endothelial Exosomes and Attenuates Apoptosis in Post-Infarction Myocardium / 中国结合医学杂志

OBJECTIVE@#To investigate the involvement of endothelial cells (ECs)-derived exosomes in the anti-apoptotic effect of Danhong Injection (DHI) and the mechanism of DHI-induced exosomal protection against postinfarction myocardial apoptosis.@*METHODS@#A mouse permanent myocardial infarction (MI) model was established, followed by a 14-day daily treatment with DHI, DHI plus GW4869 (an exosomal inhibitor), or saline. Phosphate-buffered saline (PBS)-induced ECs-derived exosomes were isolated, analyzed by miRNA microarray and validated by droplet digital polymerase chain reaction (ddPCR). The exosomes induced by DHI (DHI-exo), PBS (PBS-exo), or DHI+GW4869 (GW-exo) were isolated and injected into the peri-infarct zone following MI. The protective effects of DHI and DHI-exo on MI hearts were measured by echocardiography, Masson's trichrome staining, and TUNEL apoptosis assay. The Western blotting and quantitative reverse transcription PCR (qRT-PCR) were used to evaluate the expression levels of miR-125b/p53-mediated pathway components, including miR-125b, p53, Bak, Bax, and caspase-3 activities.@*RESULTS@#DHI significantly improved cardiac function and reduced infarct size in MI mice (P<0.01), which was abolished by the GW4869 intervention. DHI promoted the exosomal secretion in ECs (P<0.01). According to the results of exosomal miRNA microarray assay, 30 differentially expressed miRNAs in the DHI-exo were identified (28 up-regulated miRNAs and 2 down-regulated miRNAs). Among them, DHI significantly elevated miR-125b level in DHI-exo and DHI-treated ECs, a recognized apoptotic inhibitor impeding p53 signaling (P<0.05). Remarkably, treatment with DHI and DHI-exo attenuated apoptosis, elevated miR-125b expression level, inhibited capsase-3 activity, and down-regulated the expression levels of proapoptotic effectors (p53, Bak, and Bax) in post-MI hearts, whereas these effects were blocked by GW4869 (P<0.05 or P<0.01).@*CONCLUSION@#DHI and DHI-induced exosomes inhibited apoptosis, promoted the miR-125b expression level, and regulated the p53 apoptotic pathway in post-infarction myocardium.

Human Platelet-Rich Plasma-Derived Exosomes Promote the Proliferation of Schwann Cells Cultured in Vitro / 中国医学科学院学报

Objective To investigate the effect of human platelet-rich plasma-derived exosomes(PRP-exos)on the proliferation of Schwann cell(SC)cultured in vitro. Methods PRP-exos were extracted by polymerization-precipitation combined with ultracentrifugation.The morphology of PRP-exos was observed by transmission electron microscopy,and the concentration and particle size distribution of PRP-exos were determined by nanoparticle tracking analysis.Western blotting was employed to determine the expression of the marker proteins CD63,CD81,and CD9 on exosome surface and the platelet membrane glycoprotein CD41.The SCs of rats were isolated and cultured,and the expression of the SC marker S100β was detected by immunofluorescence staining.The fluorescently labeled PRP-exos were co-cultured with SCs in vitro for observation of their interaction.EdU assay was employed to detect the effect of PRP-exos on SC proliferation,and CCK-8 assay to detect the effects of PRP-exos at different concentrations(0,10,20,40,80,and 160 μg/ml)on SC proliferation. Results The extracted PRP-exos appeared as uniform saucer-shaped vesicles with the average particle size of(122.8±38.7)nm and the concentration of 3.5×1012 particles/ml.CD63,CD81,CD9,and CD41 were highly expressed on PRP-exos surface(P<0.001,P=0.025,P=0.004,and P=0.032).The isolated SCs expressed S100β,and PRP-exos could be taken up by SCs.PRP-exos of 40,80,and 160 μg/ml promoted the proliferation of SCs,and that of 40 μg/ml showed the best performance(all P<0.01). Conclusions High concentrations of PRP-exos can be extracted from PRP.PRP-exos can be taken up by SCs and promote the proliferation of SCs cultured in vitro.

The action mechanism of glioblastoma cell-derived exosome: a review / 生物工程学报

Patients with glioblastoma (GBM) generally have a bad prognosis and short overall survival after being treated with surgery, chemotherapy or radiotherapy due to the histological heterogeneity, strong invasive ability and rapid postoperative recurrence of GBM. The components of GBM cell-derived exosome (GBM-exo) can regulate the proliferation and migration of GBM cell via cytokines, miRNAs, DNA molecules and proteins, promote the angiogenesis via angiogenic proteins and non-coding RNAs, mediate tumor immune evasion by targeting immune checkpoints with regulatory factors, proteins and drugs, and reduce drug resistance of GBM cells through non-coding RNAs. GBM-exo is expected to be an important target for the personalized treatment of GBM and a marker for diagnosis and prognosis of this kind of disease. This review summarizes the preparation methods, biological characteristics, functions and molecular mechanisms of GBM-exo on cell proliferation, angiogenesis, immune evasion and drug resistance of GBM to facilitate developing new strategies for the diagnosis and treatment of GBM.

Application of hydrogel-loaded stem cell exosomes in the field of tissue regeneration / 生物工程学报

In recent years, mesenchymal stem cell (MSCs)-derived exosomes have attracted much attention in the field of tissue regeneration. Mesenchymal stem cell-derived exosomes are signaling molecules for communication among cells. They are characterized by natural targeting and low immunogenicity, and are mostly absorbed by cells through the paracrine pathway of mesenchymal stem cells. Moreover, they participate in the regulation and promotion of cell or tissue regeneration. As a scaffold material in regenerative medicine, hydrogel has good biocompatibility and degradability. Combining the two compounds can not only improve the retention time of exosomes at the lesion site, but also improve the dose of exosomes reaching the lesion site by in situ injection, and the therapeutic effect in the lesion area is significant and continuous. This paper summarizes the research results of the interaction of exocrine and hydrogel composite materials to promote tissue repair and regeneration, in order to facilitate research in the field of tissue regeneration in the future.

The role of adipose-derived exosomes in the pathological progression of atherosclerosis / 生理学报

Atherosclerosis is a chronic inflammatory disease of vascular walls with a complex etiology. In recent years, the incidence of atherosclerosis continues to increase with obesity and diabetes as major risk factors. As an important metabolic organ in the body, adipose tissue also has a powerful endocrine function. In the case of obesity and diabetes, various cytokines and exosomes derived from adipose tissue mediate organ-organ/cell-cell crosstalk, and are involved in the occurrence and development of various diseases. As an important intercellular communicator, exosomes regulate the pathological process of various cardiovascular diseases and are closely related to atherosclerosis. In this paper, we reviewed the mechanism of adipose-derived exosomes in atherosclerosis with focus on endothelial dysfunction, inflammatory response, lipid metabolism disorder and insulin resistance, hoping to provide reference for the research, diagnosis and treatment of atherosclerosis.

Exosomes derived from Nr-CWS pretreated MSCs facilitate diabetic wound healing by promoting angiogenesis via the circIARS1/miR-4782-5p/VEGFA axis / 中国天然药物

Mesenchymal stem cell (MSC)-derived exosomes (Exos) were reported to a prospective candidate in accelerating diabetic wound healing due to their pro-angiogenic effect. MSCs pretreated with chemistry or biology factors were reported to advance the biological activities of MSC-derived exosomes. Hence, this study was designed to explore whether exosomes derived from human umbilical cord MSCs (hucMSCs) preconditioned with Nocardia rubra cell wall skeleton (Nr-CWS) exhibited superior proangiogenic effect on diabetic wound repair and its underlying molecular mechanisms. The results showed that Nr-CWS-Exos facilitated the proliferation, migration and tube formation of endothelial cells in vitro. In vivo, Nr-CWS-Exos exerted great effect on advancing wound healing by facilitating the angiogenesis of wound tissues compared with Exos. Furthermore, the expression of circIARS1 increased after HUVECs were treated with Nr-CWS-Exos. CircIARS1 promoted the pro-angiogenic effects of Nr-CWS-Exos on endothelial cellsvia the miR-4782-5p/VEGFA axis. Taken together, those data reveal that exosomes derived from Nr-CWS-pretreated MSCs might serve as an underlying strategy for diabetic wound treatment through advancing the biological function of endothelial cells via the circIARS1/miR-4782-5p/VEGFA axis.