Extraction method of stem cell exosome and application of stem cell exosome in preparation of medicine for treating myocardial ischemia
Human umbilical cord mesenchymal stem cell exosomes (HUMSCs-exo) were successfully extracted and purified by adding serox to DMEM medium and undergoing multiple centrifugation and filtration. This method solved the problem of extracting and purifying HUMSCs-exo in the prior art, and achieved significant therapeutic effect in the treatment of myocardial ischemia and reperfusion injury.
Patent Information
- Application Number
- CN202510211818.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-25
- Publication Date
- 2025-05-30
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The prior art is difficult to efficiently extract and purify human umbilical cord mesenchymal stem cell exosomes (HUMSCs-exo), and its actual effects and mechanisms in the treatment of myocardial ischemia and reperfusion injury still need further research and optimization.
A method was used to culture HUMSCs in DMEM medium containing 1% serox and 10% fetal bovine serum. After multiple centrifugation and filtration, the purer HUMSCs-exo was finally obtained by high-speed centrifugation and filtering.
HUMSCs-exo extracted by this method can significantly reduce the impact of myocardial ischemia and reperfusion injury. By upregulating the expression of miR-10b-5p, it can improve the repair and regeneration process of myocardial tissue, providing a new way to treat cardiovascular diseases.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to the field of biomedicine, and particularly relates to a method for extracting stem cell exosomes and their application in the preparation of drugs for treating myocardial ischemia. Background Art
[0002] In the field of cardiovascular diseases, myocardial ischemia-reperfusion injury is an important clinical problem that urgently needs to be solved. When the blood flow to the heart is blocked and then restored, the originally ischemic myocardial tissue regains blood supply, but this process is often accompanied by a series of complex pathophysiological reactions, such as oxidative stress, inflammatory response, and apoptosis, leading to further damage to myocardial cells and even causing heart failure. Traditional treatment methods, such as drug treatment and interventional surgery, although can relieve the symptoms of myocardial ischemia to a certain extent, have limited effects on reducing reperfusion injury.
[0003] In recent years, mesenchymal stem cells (MSCs) have shown great potential in the treatment of cardiovascular diseases due to their multi-directional differentiation potential, immunomodulatory properties, and paracrine effects. Especially human umbilical cord mesenchymal stem cells (HUMSCs), as an important source of MSCs, have the advantages of easy acquisition, strong proliferation ability, and low immunogenicity, and have become a research hotspot in the treatment of cardiovascular diseases. The exosomes secreted by HUMSCs, as important carriers of intercellular information transfer, contain rich components such as proteins, nucleic acids, and lipids, and can mediate intercellular communication and affect the physiological functions of target cells. Studies have shown that HUMSCs exosomes have various biological activities such as antioxidant, anti-inflammatory, and anti-apoptotic effects, and have potential therapeutic effects on myocardial ischemia-reperfusion injury.
[0004] However, although human umbilical cord mesenchymal stem cells (HUMSCs) and their secreted exosomes have shown great therapeutic potential in the treatment of cardiovascular diseases, especially myocardial ischemia-reperfusion injury, their actual clinical application effects and mechanisms still need to be further studied and optimized. How to efficiently extract and purify HUMSCs exosomes and exert their therapeutic effects, and deeply analyze the molecular mechanism of HUMSCs exosomes in improving myocardial ischemia-reperfusion injury by regulating the expression of specific microRNAs and optimize their therapeutic application strategies are urgent problems to be solved. Summary of the Invention
[0005] One of the purposes of the present invention is to provide a method for extracting and purifying human umbilical cord mesenchymal stem cell exosomes.
[0006] To achieve the above purpose, the present invention adopts the following technical solutions:
[0007] a) Place HUMSCs in DMEM medium containing 1% styrax and 10% fetal bovine serum (FBS) for culture until the cell confluence reaches 70% - 80%;
[0008] b) Rinse the cells with PBS to remove the serum and other impurities in the culture medium;
[0009] c) Inoculate the rinsed cells into a serum-free culture medium at a ratio of 1:3 and continue culturing for 48 hours;
[0010] d) Collect the cell culture supernatant at 4°C and perform the following centrifugation treatments in sequence:
[0011] First centrifugation: Centrifuge at a speed of 500 g for 10 minutes and retain the supernatant;
[0012] Second centrifugation: Centrifuge at a speed of 2000 g for 10 minutes and continue to retain the supernatant;
[0013] Third centrifugation: Centrifuge at a speed of 10000 g for 30 minutes and still retain the supernatant;
[0014] e) Filter the supernatant with a 0.22-μm filter membrane to remove residual cell debris and impurities;
[0015] f) Centrifuge the supernatant at a speed of 100000 g for 2 hours at 4°C and retain the precipitate as the preliminarily extracted exosomes;
[0016] g) Add PBS to the preliminarily extracted exosomes, mix them well, and centrifuge at a speed of 100000 g for 2 hours again at 4°C. Retain the final precipitate as the relatively pure exosomes HUMSCs-exo;
[0017] h) Add 50 - 150 μL of PBS to the purified exosomes, freeze the PBS solution containing the exosomes in a -80°C refrigerator for subsequent use.
[0018] The second object of the present invention is to provide an application of human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo.
[0019] The above-mentioned human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo up-regulate the expression level of the miR-10b-5p gene.
[0020] Injecting the above-mentioned human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo into the myocardial tissue of model mice can improve the biochemical indexes, cardiac color Doppler ultrasound indexes, and pathological indexes of mice with myocardial ischemia-reperfusion injury.
[0021] The above-mentioned human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo reduce the impact of myocardial ischemia-reperfusion injury by up-regulating the expression of miR-10b-5p.
[0022] Use of the above-mentioned human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo in the preparation of a drug for myocardial ischemia-reperfusion injury.
[0023] A third object of the present invention is to provide the use of stem cell exosomes (especially human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo) in the preparation of a drug for treating myocardial ischemia.
[0024] Furthermore, HUMSCs-exo is used as an active ingredient for the preparation of a therapeutic drug for myocardial ischemia. The drug can deliver HUMSCs-exo into the body of a myocardial ischemia patient through direct injection or other appropriate administration methods, so as to reduce the degree of myocardial cell injury, promote the repair and regeneration of myocardial tissue, and thus improve the clinical symptoms and cardiac function of myocardial ischemia patients.
[0025] Compared with the prior art, the beneficial effects of the present invention are as follows: The purified HUMSCs-exo extracted in the present invention shows significant curative effects in the treatment of myocardial ischemia-reperfusion injury. When HUMSCs-exo is injected into the myocardial tissue of model mice, the degree of myocardial cell injury is reduced, and the repair and regeneration process of myocardial tissue is promoted. HUMSCs-exo can further reduce the impact of myocardial ischemia-reperfusion injury by upregulating the expression of the key microRNA - miR-10b-5p. The method for extracting and purifying HUMSCs exosomes provided by the present invention and its application in the treatment of myocardial ischemia-reperfusion injury open up a new way for the treatment of cardiovascular diseases. Description of the Drawings
[0026] Figure 1 It is a transmission electron microscope characterization diagram of human umbilical cord mesenchymal stem cell exosomes, scale bar: 100 nm.
[0027] Figure 2 It is the expression level of miR-10b-5p in exosomes extracted from human umbilical cord mesenchymal stem cells cultured with / without styrax.
[0028] Figure 3 It is the detection results of serological indexes of mice in the blank group (without any intervention), control group (sham operation group), model group, and treatment group.
[0029] Figure 4 It is the echocardiogram detection results of mice in the blank group (without any intervention), control group (sham operation group), model group, and treatment group.
[0030] Figure 5 It is the pathological detection results of mice in the blank group (without any intervention), control group (sham operation group), model group, and treatment group, scale bar: 20 μm.
[0031] Figure 6 The gene-level expression results of mice in the blank group (without any intervention), the control group (sham operation group), the model group, and the treatment group. Specific implementation manner
[0032] Example 1: Extraction of human umbilical cord mesenchymal stem cell exosomes
[0033] Human umbilical cord mesenchymal stem cells (HUMSCs) were cultured in DMEM medium containing 1% styrax and 10% fetal bovine serum (FBS). When the cell confluence reached 70% to 80%, the cells were rinsed with PBS to remove the serum and other impurities in the medium. The cells were seeded into serum-free medium at a ratio of 1:3 and cultured for another 48 hours. The cell culture supernatant was collected at 4°C throughout the process: first, centrifuged at 500 g for 10 minutes, and the supernatant was retained; then centrifuged at 2000 g for another 10 minutes, and the supernatant was still retained; then centrifuged at 10000 g for 30 minutes, and the supernatant was still retained; the supernatant was filtered through a 0.22 μm filter membrane to remove residual cell debris and impurities. Centrifuged at 100000 g (4°C) for 2 hours, and the precipitate was retained at this time, which was the preliminarily extracted exosomes; PBS was added to the precipitate to mix it well. Centrifuged again at 100000 g (4°C) for 2 hours, and the final precipitate was retained, which was the relatively pure exosomes. 50 - 150 μL of PBS was added to the purified exosomes (HUMSCs-exo). The PBS solution containing exosomes was frozen in a -80°C refrigerator for subsequent use.
[0034] Comparative Example 1: The difference between the method for extracting human umbilical cord mesenchymal stem cell exosomes in this example and that in Example 1 is that the DMEM medium only contains 10% fetal bovine serum and does not contain 1% styrax.
[0035] Example 2: Characterization of human umbilical cord mesenchymal stem cell exosomes
[0036] The exosome precipitate obtained in Example 1 and Comparative Example 1 was resuspended with 100 μL of 2.5% glutaraldehyde solution to ensure that the precipitate was fully dispersed. Fix overnight at 4°C to stabilize the structure of the exosomes. 20 μL of the fixed exosome sample was carefully dripped onto a clean copper mesh (the copper mesh was hydrophilically pretreated to improve the adhesion of the sample). Gently remove excess liquid with dust-free paper, taking care to avoid touching the sample on the copper mesh. Dry the copper mesh at room temperature for 1-2 minutes to ensure that the sample is completely dry. Use 2% uranyl acetate solution to stain the sample on the copper mesh at room temperature for 2 minutes. After staining, gently remove excess staining liquid with dust-free paper again, and dry the copper mesh at room temperature. Carefully transfer the copper mesh to a small drop of ultrapure water, soak for 2 minutes, and then gently remove ultrapure water with dust-free paper to ensure that the copper mesh is completely dry. Place the treated copper mesh in a transmission electron microscope for observation.
[0037] like Figure 1 As shown in the figure, the exosomes observed under transmission electron microscopy all showed a typical round cup-shaped or disc-shaped structure, and the diameter of the exosomes was about 100nm, which was consistent with expectations. In addition, it can be observed that the surface of the exosomes has a certain membrane structure, which further confirms its identity as an extracellular vesicle.
[0038] Example 3: Real-time fluorescence quantitative PCR detection
[0039] Total exosome RNA was extracted. Subsequently, total RNA was reverse transcribed using the RevertAid cDNA synthesis kit. Quantitative RT-PCR was performed using SYBR Green premix on an ABI 7900HT system. All reactions were performed in triplicate and were performed by 2 -ΔΔCt The gene expression was determined by the method. The conditions of the 10 μL reverse transcription reaction were as follows: 95℃30sec; 95℃5sec, 60℃30sec (40 cycles) within the cycle. After the cycle was completed, the ct values of three replicate wells for each gene and each sample were obtained. The internal reference of miR-10b-5p was U6. Table 1 lists the primer sequences used in this study.
[0040] Table 1 Primer sequences
[0041]
[0042] Styrax has the effects of opening the orifices, removing filth, relieving depression, removing phlegm, and relieving pain. This study found that the expression level of miR-10b-5p in the exosomes secreted by HUMSCs cultured in DMEM medium containing 1% styrax was significantly higher than that in the medium without styrax ( Figure 2)。This finding suggests that styrax may exert its cardioprotective effect by regulating the expression of miR-10b-5p in HUMSCs exosomes. Considering the aromatic-resuscitation effect of styrax in traditional Chinese medicine and its reported protective effect on central nervous system diseases, we further speculate that styrax may indirectly or directly affect the expression of miR-10b-5p in HUMSCs exosomes by regulating blood-brain barrier permeability, inhibiting inflammatory responses, and antioxidant stress injury and other mechanisms.
[0043] Example 4: Preparation, grouping, and treatment of myocardial ischemia-reperfusion model
[0044] Twenty-four 4-week-old male C57BL / 6 mice were housed in an animal room at 25 ± 1°C with a humidity of 65 ± 5% for 1 week under a 12-hour light / dark cycle to acclimatize to the environment before the experiment. They were divided into 4 groups: blank group (without any intervention), control group (sham operation group), model group, and treatment group (human umbilical cord mesenchymal stem cell exosomes prepared in Example 1). The mice were fasted for 12 h before surgery and had free access to water. The following steps were used for ligation of the left anterior descending branch (LAD): (1) Anesthetize the mice with isoflurane connected to a ventilator; (2) Open the left chest at the fourth intercostal space to expose the heart; (3) Ligate the left anterior descending artery with an 8-0 suture; (4) The mice in the control group underwent a sham operation, that is, an 8-0 suture needle was passed through the tissue near the anterior descending branch of the coronary artery, but the coronary artery was not actually ligated, and the simulated ligation operation was completed within 10 seconds; in the human umbilical cord mesenchymal stem cell exosome treatment group, after ligation of the LAD, an appropriate site (myocardial tissue) was selected for injection of 0.1% HUMSCs-exo exosomes, that is, 1 μg of HUMSCs exosomes was dissolved in 100 μL PBS. The entire experiment was carried out strictly in accordance with the Guidelines for the Ethical Review of Laboratory Animal Welfare, National Standard of the People's Republic of China (GB / T 35892-2018).
[0045] Example 5: Detection of serological indicators
[0046] Collect 1 mL of blood from the jugular vein of the mice, let it stand at room temperature for 30 min, then centrifuge it at 10000 g for 10 min at 4°C, take the upper serum, and use a blood biochemical analyzer to measure the levels of CK (creatine kinase), CK-MB (creatine kinase isoenzyme), and LDH (lactate dehydrogenase).
[0047] As Figure 3As shown, first, we note that in the blank group, since no surgery or therapeutic intervention was performed, the serum CK, CK-MB, and LDH levels of the mice remained within the normal range, indicating that the myocardial cells of the mice in the blank group were not damaged or only slightly damaged. In contrast, although the mice in the control group underwent a surgical procedure similar to that of the model group, since the left anterior descending artery was not truly ligated, their serum CK, CK-MB, and LDH levels, although slightly elevated, did not reach the levels of the model group. This result suggests that the surgical procedure itself may cause a certain degree of damage to the myocardial cells of the mice, but this damage is minor and not sufficient to cause significant changes in serological indicators. The mice in the model group underwent a true ligation of the left anterior descending artery, resulting in myocardial ischemia-reperfusion injury. Therefore, the serum CK, CK-MB, and LDH levels in the model group increased significantly, indicating that the myocardial cells were severely damaged. In addition, the changes in these indicators are closely related to the pathophysiological process of myocardial ischemia-reperfusion injury, further verifying the success of model preparation. Finally, the mice in the human umbilical cord mesenchymal stem cell exosome treatment group received exosome treatment after ligation of the left anterior descending artery. The results showed that although the serum CK, CK-MB, and LDH levels in this group of mice were still higher than those in the blank group, they were significantly lower than those in the model group and also showed a downward trend compared with the control group. This result suggests that human umbilical cord mesenchymal stem cell exosome treatment may alleviate the myocardial cell damage caused by myocardial ischemia-reperfusion injury through a certain mechanism, thereby reducing the levels of serological indicators.
[0048] Example 6: Evaluation of Echocardiogram Indexes
[0049] Before surgery, a Vevo 2100 echocardiogram system was used to perform two-dimensional echocardiography on the mice to establish baseline data on their cardiac function. According to the established surgical procedure, left anterior descending artery ligation was performed on the mice. On the 1st, 3rd, and 5th days after surgery: Echocardiography was performed on the surgically treated mice to evaluate changes in cardiac function. In each examination, M-mode tracing technology was used to accurately measure the thickness of the anterior and posterior walls of the mice's hearts at the end of diastole and systole. At the same time, the diastolic and systolic diameters of the left ventricles of the mice were measured to comprehensively evaluate changes in their cardiac structure and function.
[0050] As the control group that did not receive any intervention, the baseline data of the cardiac function of the mice in the blank group remained stable before and after surgery. Whether it was the thickness of the anterior and posterior walls or the diastolic and systolic diameters of the left ventricles, they all remained within the normal range, indicating that the cardiac function of the mice in this group was not affected ( Figure 4)。The mice in the control group underwent a surgical procedure similar to that of the model group. However, since the left anterior descending artery was not truly ligated, the changes in their cardiac function were relatively small. During the echocardiogram examination after the surgery, although slight changes in cardiac structure and function were observed, such as a slight increase in ventricular wall thickness, these changes were not significant and gradually stabilized over time, indicating that the sham surgery procedure had a minor impact on the cardiac function of the mice. The mice in the model group received a true ligation of the left anterior descending artery, resulting in myocardial ischemia-reperfusion injury. During the echocardiogram examination after the surgery, obvious changes in cardiac structure and function were observed, including a significant reduction in ventricular wall thickness, an increase in the diastolic and systolic diameters of the left ventricle, etc. These changes indicated that the cardiac function of the mice in the model group was severely damaged. Over time, these injuries gradually worsened, leading to further deterioration of cardiac function. The mice in the human umbilical cord mesenchymal stem cell exosome treatment group received human umbilical cord mesenchymal stem cell exosome treatment after ligation of the left anterior descending artery. During the echocardiogram examination after the surgery, relatively minor changes in cardiac structure and function were observed in this group of mice. Compared with the model group, the degree of reduction in ventricular wall thickness was smaller, and the increase in the diastolic and systolic diameters of the left ventricle was also not significant. These results suggest that human umbilical cord mesenchymal stem cell exosome treatment may alleviate the cardiac structure and function changes caused by myocardial ischemia-reperfusion injury through a certain mechanism, thereby improving the cardiac function of the mice.
[0051] Example 7: Hematoxylin-eosin (HE) staining
[0052] One week after treatment with / without treatment, the mouse hearts were collected. The heart tissues were fixed with 4% paraformaldehyde, dehydrated with gradient alcohol, embedded in paraffin, cut into 4-μm sections, stained with hematoxylin-eosin (HE), dehydrated again with gradient alcohol, sealed with neutral gum, observed under an optical microscope, and the target areas were selected for photography. According to the staining results and morphological characteristics, the structure and function of the heart tissues were evaluated.
[0053] After a one-week observation period, we collected the heart tissues of all groups of mice, as Figure 5As shown, the heart tissue structure of the blank group was clear, the cardiomyocytes were arranged neatly, without obvious inflammatory cell infiltration or fibrosis signs, showing normal histological features. The control group (sham operation group) was similar to the blank group, the overall structure of the heart tissue was well maintained, the morphology of cardiomyocytes was normal, and no significant pathological changes were observed, indicating that the sham operation had no obvious effect on the heart tissue. The heart tissue of the model group showed obvious pathological changes, including disordered arrangement of cardiomyocytes, necrosis of some cardiomyocytes, inflammatory cell infiltration and local fibrosis. These changes are typical manifestations of myocardial ischemia-reperfusion injury. Compared with the model group, the pathological changes of the heart tissue in the human umbilical cord mesenchymal stem cell exosome treatment group were significantly reduced. The cardiomyocytes were arranged more neatly, the necrotic area was reduced, and the degree of inflammatory cell infiltration and fibrosis was also significantly decreased. This indicates that the treatment with human umbilical cord mesenchymal stem cell exosomes has a certain protective effect on myocardial ischemia-reperfusion injury.
[0054] Example 8: Real-time fluorescence quantitative PCR detection
[0055] To further explore the effect of human umbilical cord mesenchymal stem cell exosome treatment on gene expression after myocardial ischemia-reperfusion injury, we performed real-time fluorescence quantitative PCR detection according to the experimental steps of Example 3. As Figure 6 shown, there was no significant difference in the miR-10b-5p expression level between the blank group and the control group, and both remained at a low level. Compared with the blank group and the control group, the miR-10b-5p expression level in the model group decreased significantly, which may be related to pathological processes such as inflammatory response and apoptosis after myocardial ischemia-reperfusion injury. Compared with the model group, the miR-10b-5p expression level in the human umbilical cord mesenchymal stem cell exosome treatment group increased significantly and was close to the levels of the blank group and the control group. This indicates that the treatment with human umbilical cord mesenchymal stem cell exosomes may alleviate the pathological processes after myocardial ischemia-reperfusion injury by upregulating the expression of miR-10b-5p.
[0056] In summary, through biochemical indexes, cardiac ultrasound indexes, pathological indexes and molecular biology indexes, the treatment with human umbilical cord mesenchymal stem cell exosomes can effectively improve the heart tissue structure after myocardial ischemia-reperfusion injury, specifically manifested as reducing cardiomyocyte damage, inhibiting inflammatory cell infiltration and fibrosis process; at the same time, this treatment can also downregulate the gene expression levels closely related to the injury, such as the downregulation of the expression of specific microRNAs confirmed by real-time fluorescence quantitative PCR detection. These comprehensive results provide strong experimental evidence for the application of human umbilical cord mesenchymal stem cell exosomes in the treatment of cardiovascular diseases.
[0057] The above embodiments are only the preferred embodiments of the present invention, and the scope of protection of the present invention cannot be limited by this. Any non-substantive changes and substitutions made by those skilled in the art on the basis of the present invention belong to the scope of protection required by the present invention.
Claims
1. A method for extracting human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo, characterized in that The following steps are involved: a) HUMSCs were cultured in DMEM medium containing 1% styrax and 10% fetal bovine serum (FBS) until the cells reached a confluence of 70% to 80%; b) Wash the cells with PBS to remove serum and other impurities in the culture medium; c) inoculating the washed cells into serum-free culture medium at a ratio of 1:3 and continuing to culture for 48 hours; d) Collect the cell culture supernatant at 4°C and perform the following centrifugation treatments in sequence: First centrifugation: Centrifuge at 500g for 10 minutes and keep the supernatant; Second centrifugation: Centrifuge at 2000g for 10 minutes and keep the supernatant; The third centrifugation: centrifuge at 10000g for 30 minutes, and retain the supernatant; e) filtering the supernatant using a 0.22 μm filter membrane to remove residual cell debris and impurities; f) centrifuging the supernatant at 100,000 g for 2 hours at 4°C, and retaining the precipitate as the initially extracted exosomes; g) adding PBS to the initially extracted exosomes to mix them thoroughly, and centrifuging them again at 100,000 g for 2 hours at 4°C, retaining the final precipitate as the purer exosomes of HUMSCs-exo; h) Add 50-150 μL of PBS to the purified exosomes, and freeze the PBS solution containing exosomes in a -80°C refrigerator for subsequent use.
2. An application of human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo, characterized in that: The human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo injected into the myocardial tissue of model mice can improve the biochemical indexes, cardiac color Doppler ultrasound indexes, and pathological indexes of mice with myocardial ischemia-reperfusion injury.
3. The use of human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo as claimed in claim 2, characterized in that: The human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo injected into the myocardial tissue of model mice can improve the levels of creatine kinase CK, creatine kinase isoenzyme CK-MB, and lactate dehydrogenase LDH in the serum of mice with myocardial ischemia-reperfusion injury.
4. The use of human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo as claimed in claim 2, characterized in that: The human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo injected into the myocardial tissue of model mice can improve the cardiac function of mice with myocardial ischemia-reperfusion injury.
5. The use of human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo as claimed in claim 2, characterized in that: The human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo injected into the myocardial tissue of model mice can reduce myocardial cell apoptosis in mice with myocardial ischemia-reperfusion injury.
6. The use of human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo as claimed in claim 2, characterized in that: The human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo alleviate the effects of myocardial ischemia-reperfusion injury by upregulating the expression of miR-10b-5p.
7. The use of human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo as claimed in claim 2, characterized in that: The application of the human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo in the preparation of a medicine for myocardial ischemia-reperfusion injury.
8. Application of human umbilical cord mesenchymal stem cell exosomes HUMSCs-exo in the preparation of drugs for treating myocardial ischemia.