ObjectiveTo comprehensively analyze the recent advancements in the field of mesenchymal stem cells (MSCs) derived exosomes (MSCs-exosomes) in tissue repair.
MethodsThe literature about MSCs-exosomes in tissue repair was reviewed and analyzed.
ResultsExosomes are biologically active microvesicles released from MSCs which are loaded with functional proteins, RNA, and microRNA. Exosomes can inhibit apoptosis, stimulate proliferation, alter cell phenotype in tissue repair of several diseases through cell-to-cell communication.
ConclusionMSCs-exosomes is a novel source for the treatment of tissue repair. Further research of MSCs-exosomes biofunction, paracellular transport, and treatment mechanism will help the transform to clinical application.
Objective To investigate the effects of exosomes from cultured human retinal pigment epithelium (ARPE-19) cells affected by oxidative stress on the proliferation and expression of vascular endothelial growth factor-A (VEGF-A) and Akt of ARPE-19 cells. Methods Culture ARPE-19 cells. The concentration of 2.5 μmol/L rotenone was selected to simulate oxidative stress and isolated ARPE-19-exosome. Exosomes were isolated by ExoQuick exosome precipitation solution. Transmission electron microscopy was used to identify the morphology of exosomes. Western blot was used to detect exosomes’ surface-specific maker protein CD63. ARPE-19 cells affected by oxidative stress were cultured with exosome as experimental group, normal ARPE-19 cells were cultured with exosome as control group. The cell proliferation was examined by methyl thiazolyl tetrazolium assay. Western blot and immunofluorescence assay were used to detect the expression levels of VEGF-A and Akt protein. Real-time quantitative polymerase chain reaction (RT-PCR) was used to detect the levels of VEGF-A mRNA and Akt mRNA. Results The diameter of normal ARPE-19-exosomes ranged from 50 to 150 nm. The isolated exosomes expressed CD63. AREP-19 cells were cultured with ARPE-19 (affected by rotenone)-exosome, the cell viability in experimental group was significantly reduced than in the control group. Green fluorescence was observed in the cytoplasm under fluorescence microscope. Compared with the control group, VEGF-A was up-regulated expressed and Akt was down-regulated expressed. Western blot results showed that, VEGF-A protein expression in the experimental group were higher than the control group. Akt protein expression in the experimental group were less than the control group. The difference was statically significant (t=3.822, 6.527;P＜0.05). RT-PCR results showed that VEGF-A mRNA expression levels was higher in the experimental group than the control group. Akt mRNA expression levels was lower in the experimental group than the control group. The difference was statically significant (t=8.805, ?7.823;P＜0.05). Conclusions Exosomes from ARPE-19 cells affected by oxidative stress inhibit the proliferation of normal ARPE-19 cells, increase the expression of VEGF-A and reduce the expression of Akt.
Exosomes derived from mesenchymal stem cells are a class of discoid extracellular vesicles with a diameter of 40—100 nm discovered in recent years. They contain abundant nucleic acids, proteins and lipids, and have abundant biological information. Exosomes derived from mesenchymal stem cells regulate cell activities by acting on receptor cells, and promote regeneration of many tissues, such as bone, cartilage, skin, intervertebral disc, and spinal nerves. Studies have shown that exosomes derived from mesenchymal stem cells have similar biological functions as mesenchymal stem cells, and are more stable and easier to be preserved. Therefore, they have been increasingly applied in the field of orthopedic tissue repair in recent years. This paper reviews the application of exosomes derived from mesenchymal stem cells in orthopedics.
This research aims to investigate the encapsulation and controlled release effect of the newly developed self-assembling peptide R-LIFE-1 on exosomes. The gelling ability and morphological structure of the chiral self-assembling peptide (CSAP) hydrogel were examined using advanced imaging techniques, including atomic force microscopy, transmission electron microscopy, and cryo-scanning electron microscopy. The biocompatibility of the CSAP hydrogel was assessed through optical microscopy and fluorescent staining. Exosomes were isolated via ultrafiltration, and their quality was evaluated using Western blot analysis, nanoparticle tracking analysis, and transmission electron microscopy. The controlled release effect of the CSAP hydrogel on exosomes was quantitatively analyzed using laser confocal microscopy and a BCA assay kit. The results revealed that the self-assembling peptide R-LIFE-1 exhibited spontaneous assembly in the presence of various ions, leading to the formation of nanofibers. These nanofibers were cross-linked, giving rise to a robust nanofiber network structure, which further underwent cross-linking to generate a laminated membrane structure. The nanofibers possessed a large surface area, allowing them to encapsulate a substantial number of water molecules, thereby forming a hydrogel material with high water content. This hydrogel served as a stable spatial scaffold and loading matrix for the three-dimensional culture of cells, as well as the encapsulation and controlled release of exosomes. Importantly, R-LIFE-1 demonstrated excellent biocompatibility, preserving the growth of cells and the biological activity of exosomes. It rapidly formed a three-dimensional network scaffold, enabling the stable loading of cells and exosomes, while exhibiting favorable biocompatibility and reduced cytotoxicity. In conclusion, the findings of this study support the notion that R-LIFE-1 holds significant promise as an ideal tissue engineering material for tissue repair applications.
Mesenchymal stem cells (MSCs) are considered as an ideal treatment for multiple diseases including ocular disease. Recent studies have demonstrated that MSCs-derived exosomes have similar functions with MSCs. Exosomes are nanovesicles surrounded by a phospholipid layer that shuttle active cargo between different cells. They are capable of passing the biological barrier and have potentials to be utilized as natural carrier for the ocular drug delivery.
ObjectiveTo investigate the effects of exosomes from adipose-derived stem cells (ADSCs) on peripheral nerve regeneration, and to find a new treatment for peripheral nerve injury. MethodsThirty-six adult Sprague Dawley (SD) rats (male or female, weighing 220-240 g) were randomly divided into 3 groups (n=12). Group A was the control group; group B was sciatic nerve injury group; group C was sciatic nerve injury combined with exosomes from ADSCs treatment group. The sciatic nerve was only exposed without injury in group A, and the sciatic nerve crush injury model was prepared in groups B and C. The SD rats in groups A and B were injected with PBS solution of 200 μL via tail veins; the SD rats in group C were injected with pure PBS solution of 200 μL containing 100 μg exosomes from ADSCs, once a week and injected for 12 weeks. At 1 week after the end of the injection, the rats were killed and the sciatic nerves were taken at the part of injury. The sciatic nerve fiber bundles were observed by HE staining; the SCs apoptosis of the sciatic nerve tissue were detected by TUNEL staining; the ultrastructure and SCs autophagy of the sciatic nerve were observed by transmission electron microscope. ResultsGross observation showed that there was no obvious abnormality in the injured limbs of group A, but there were the injured limbs paralysis and muscle atrophy in groups B and C, and the degree of paralysis and muscle atrophy in group C were lighter than those in group B. HE staining showed that the perineurium of group A was regular; the perineurium of group B was irregular, and there were a lot of cell-free structures and tissue fragments in group B; the perineurium of group C was more complete, and significantly well than that of group B. TUNEL staining showed that the SCs apoptosis was significantly increased in groups B and C than in group A, in group B than in group C (P<0.01). Transmission electron microscope observation showed that the SCs autophagosomes in groups B and C were significantly increased than those in group A, but the autophagosomes in group C were significantly lower than those in group B. ConclusionThe exosomes from ADSCs can promote the peripheral nerve regeneration. The mechanism may be related to reducing SCs apoptosis, inhibiting SCs autophagy, and reducing nerve Wallerian degeneration.
ObjectiveTo investigate whether exosomes derived from atorvastatin (ATV)-pretreated human umbilical cord mesenchymal stem cells (ATV-MSC-EXO) alleviate high glucose-induced injury in human retinal vascular endothelial cells (HREC) via the protein kinase B (AKT)/endothelial nitric oxide synthase (eNOS) signaling pathway. MethodsThe optimal pretreatment concentration of ATV was determined using the cell counting Kit-8 (CCK-8) assay. Exosomes derived from mesenchymal stem cells (MSC-EXO) and ATV-pretreated MSC (ATV-MSC-EXO) were isolated and extracted, and their morphology and surface markers were characterized by transmission electron microscopy, nanoparticle tracking analysis, and Western blotting (WB). The uptake capacity of exosomes by human retinal vascular endothelial cells (HREC) was evaluated using a fluorescence labeling assay. In vitro cultured HREC were divided into the following groups: normal control group (NC group), high glucose group (HG group), high glucose+MSC-EXO group (MSC-EXO group), high glucose+ATV-MSC-EXO group (ATV-MSC-EXO group), high glucose+ATV-MSC-EXO+AKT inhibitor group (ATV-MSC-EXO-MK-2206-2HCL group), and high glucose+ATV-MSC-EXO+eNOS inhibitor group (ATV-MSC-EXO-L-NAME group). Cell proliferation and apoptosis were detected using CCK-8 and flow cytometry, respectively. The protein expression levels of B-cell lymphoma/leukemia-2 (Bcl-2), Bcl-2-associated protein (Bax), and Caspase-3 were measured by WB. In addition, the regulatory effects of ATV-MSC-EXO on the AKT/eNOS signaling pathway and its downstream functional molecules were analyzed by detecting the phosphorylation levels of AKT (P-AKT/AKT) and eNOS (P-eNOS/eNOS) via WB, the mRNA expression levels of AKT and eNOS by quantitative real-time polymerase chain reaction, and the concentrations of nitric oxide (NO) and endothelin-1 (ET-1) using commercial NO and ET-1 assay kits. ResultsThe optimal pretreatment concentration of ATV was 1 μmol/L. ATV-MSC-EXO exhibited similar morphology and particle size to MSC-EXO and were efficiently taken up by HREC. Under high glucose conditions, ATV-MSC-EXO significantly enhanced the viability of HREC (F=83.24, P＜0.000 1) and inhibited apoptosis (F=77.39, P＜0.000 1). WB analysis further confirmed that ATV-MSC-EXO upregulated the expression of the anti-apoptotic protein Bcl-2 (F=53.17), while downregulating the pro-apoptotic proteins Bax (F=36.49) and Caspase-3 (F=60.75) (P＜0.001). In addition, ATV-MSC-EXO markedly increased the protein levels of P-AKT/AKT (F=107.60) and P-eNOS/eNOS (F=38.59), as well as the relative mRNA expression of AKT, eNOS (F=203.60, 315.00; P＜0.000 1). Furthermore, ATV-MSC-EXO promoted NO production (F=407.40) and suppressed the relative expression of ET-1 (F=49.76) (P＜0.000 1). ConclusionATV-MSC-EXO enhances the viability and inhibits apoptosis of HREC under high glucose conditions by activating the AKT/eNOS signaling pathway.
Bone malignancies exhibit the characteristics of high incidence, poor prognosis, and strong chemoresistance. Exosomal microRNAs can regulate the proliferation of bone malignant cells, improve chemoresistance, influence cell communication and the microenvironment, and have significant potential in the diagnosis and treatment of bone malignancies. Due to their stability, exosomal microRNAs can serve as non-invasive biomarkers for diagnosis and prognosis. However, their widespread application in clinical settings requires standardized research. This review summarizes the progress of exosomal microRNA research in various bone malignancies including osteosarcoma, chondrosarcoma, Ewing sarcoma, and fibrosarcoma, to provide new theoretical foundations and perspectives for the field.
Exosomes are nanovesicles actively secreted by cells, which selectively encapsulate biologically active molecules such as proteins, RNA, and cytokines. They play an important role in intercellular communication, immune regulation, and maintenance of homeostasis, which can also be used as carriers for targeted drug delivery. Retinal ischemia-reperfusion injury (RIRI) is a retinopathy that seriously threatens human vision. At present, the clinical treatment of these diseases are symptomatic treatments, and some patients have poor efficacy or even blindness. As extracellular vesicles rich in functional proteins and RNAs, exosomes can not only be used as drugs for the treatment of RIRI, but also be used as carriers for drug delivery to play synergistic therapeutic effects. In the future, with the deepening of the research on the molecular structure, contents and biological functions of exosomes, as well as the continuous development of ophthalmic biology and genetic engineering technology, exosomes are expected to exert their great potential as therapeutic drugs and carriers, and become an important means of treating RIRI.
Objective
To investigate the protective effect of the exosome on the organ damage induced by ische-mia-reperfusion (I/R) so as to provide a new way for the treatment of I/R damage.
Methods
The literature related to the treatment of I/R damage was reviewed and analyzed.
Results
The exosome volume is small and it is present in blood, cerebrospinal fluid, and urine, which has the function to cross the blood-brain barrier, and protect the heart, brain and other organs after I/R damage.
Conclusion
Exosome is a new material for the treatment of I/R organ injury, and it is important to understand the protective effect and possible mechanism.
