Application of acellular matrix loaded Sr-Se coated SiO2 and adipose tissue-derived stem cells in sequential treatment of volumetric muscle defect

Abstract

The invention belongs to the field of preparation of medical materials, and particularly relates to application of acellular matrix loaded Sr-Se coated SiO2 and adipose-derived mesenchymal stem cells in sequential treatment of volumetric muscle defects. On the basis of the Sr-Se-coated SiO2 nano composite material, a composite filling scaffold is developed in combination with a tissue engineering scaffold, and the effect of the composite filling scaffold in the VML treatment process is researched. The filler is composed of three parts, namely a nano material Sr-Se coated SiO2 with multiple functions of resisting inflammatory response, promoting vascularization and the like, ADSCs with myogenic differentiation potential and a dECM composite scaffold used for loading contents, the composite filling scaffold provided by the invention can improve the problem that traditional VML treatment is difficult, and sequential treatment of personalized guide VML is achieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of medical material preparation, and particularly relates to application of a decellularized matrix loaded with Sr-Se@SiO2 and adipose-derived mesenchymal stem cells in sequential treatment of volumetric muscle loss. BACKGROUND

[0002] Skeletal muscle usually has very high regenerative capacity after slight injury, while volumetric muscle loss (VML) is a skeletal muscle injury caused by primary or secondary injury and exceeding the self-repairing capacity, which eventually causes long-term disability of the patient's limbs. VML caused by traffic accidents, natural disasters, gun battles, etc. may affect hundreds of millions of people with long-term pain and organ dysfunction. The muscle repair process after VML injury is characterized by excessive inflammatory response and excessive collagen deposition. In this case, the formation speed of fibrous tissue exceeds the differentiation and maturation speed of myoblasts, and the formed hypertrophic and non-functional scar seriously hinders the fusion of myotubes, eventually leading to permanent muscle loss and lifelong disability of the patient. The disability caused by VML makes the patient unable to return to work, which brings a heavy burden to the patient and society.

[0003] The severe loss of satellite cells and their niche elements such as basal lamina, interstitial cells and vascular network after VML leads to impaired muscle tissue regeneration. At the same time, after VML occurs, the skeletal muscle activates its repair system, and this pathophysiological process is divided into three stages: inflammation, new tissue formation and tissue remodeling. Current treatment methods for VML include physical therapy, scar tissue debridement and muscle transposition. However, due to the inability of these methods to reverse the pathological changes that occur after VML injury, the success rate of treatment is low. The success of treatment requires a large amount of muscle formation to replace the lost tissue, sufficient vascularization to supply blood flow, nerve function domination to generate action potential, and effective immune regulation to reduce fibrosis and support tissue regeneration.

[0004] Therefore, exploring the repair mechanism of VML and seeking new methods for VML treatment have extremely great significance for human health and social development. SUMMARY

[0005] To solve the above problems, the application develops a composite filling scaffold on the basis of Sr-Se@SiO2 nanocomposite material combined with tissue engineering scaffold, and studies the role of the composite filling scaffold in the VML treatment process. The filler is composed of three parts, namely the nanomaterial Sr-Se@SiO2 with multiple functions such as anti-inflammatory response and promoting vascularization, ADSCs with myogenic differentiation potential, and a dECM composite scaffold for loading contents. The composite filling scaffold provided by the application will improve the problems of traditional VML treatment and realize personalized sequential treatment of VML.

[0006] In a first aspect, the present application provides a preparation method of Sr-Se@SiO2-dECM tissue engineering scaffold, the preparation method comprising the following steps,

[0007] Step 1, Se@SiO2 nanoparticles are prepared by reverse microemulsion method;

[0008] Step 2, Se@SiO2 nanoparticles obtained in step 1 are dissolved in deionized water with SrCl2·6H2O and PVP, and ammonia water is added dropwise, and after stirring, it is placed in a polytetrafluoroethylene reaction kettle and reacted at 130-150℃ for 4-6h, and then washed with deionized water to obtain Sr-Se@SiO2 nanoparticles;

[0009] Step 3, the Gelma sample is placed in a pretreated tissue culture polystyrene plate, and ADSCs are placed in the tissue culture polystyrene plate, and a growth medium is added to culture until the ADSCs and the Gelma sample are fused, and then ascorbic acid is added to treat for 6-8 days to obtain ADSCs loaded on a gelatin sheet;

[0010] Step 4, the ADSCs obtained in step 3 are cultured in an extraction buffer for 3-8 minutes, and glutaraldehyde is used for fixation to obtain dECM derived from ADSCs;

[0011] Step 5, the Sr-Se@SiO2 nanoparticles prepared in step 3 are uniformly sprayed on the dECM derived from ADSCs prepared in step 4 to obtain a Sr-Se@SiO2-dECM tissue engineering scaffold with nanostructure.

[0012] In some embodiments, step 1 comprises the following steps: n-hexanol, Triton X-100, n-hexane are added to deionized water and stirred uniformly, and copper selenide solution is added and stirred for 3-5 min, then tetraethyl orthosilicate is added and stirred for 3-5 min, then ammonia water is added to make the solution present ink blue, and after stirring for 20-28h, it is washed by centrifugation with anhydrous ethanol to obtain.

[0013] In some embodiments, the volume ratio of n-hexanol, Triton X-100 and n-hexane is 1:1:10, the volume ratio of the copper selenide solution to the n-hexanol is 3:2, and the volume ratio of the copper selenide solution to the tetraethyl orthosilicate is 10-12:1.

[0014] In some embodiments, the preparation method of the copper selenide solution comprises: putting Se and NaOH into deionized water, heating to 45-55℃, stirring until the selenium is completely dissolved, then sequentially adding N2H4·H2O, CuCl2·2H2O, 2mL of oleylamine (OA) into the mixed solution, maintaining at 80-120℃ for 2-5h, washing with ethanol for 2-4 times, and then obtaining Cu2-xSe nanoparticles, and then dispersing the Cu2-xSe in n-hexane.

[0015] In some embodiments, the mass ratio of the Se@SiO2 nanoparticles to SrCl2·6H2O is 1:3-5, the mass ratio of the Se@SiO2 nanoparticles to the PVP is 95-105:1, the mass-volume ratio of the Se@SiO2 nanoparticles to the ammonia water (25%-30%) is 20-80mg:1mL, the reaction temperature in the polytetrafluoroethylene reaction kettle is 120-160℃, and the reaction time is 2-8h.

[0016] In some embodiments, the preparation method of the Gelma sample comprises: pouring 5-15wt% of the Gelma solution into a mold, exposing to ultraviolet light for crosslinking to obtain a sample, and freeze-drying the sample overnight to obtain the Gelma sample.

[0017] In a second aspect, the present application further provides a Sr-Se@SiO2-dECM tissue engineering scaffold prepared by the preparation method of the first aspect.

[0018] In a third aspect, the present application further provides an application of the Sr-Se@SiO2-dECM tissue engineering scaffold of the second aspect in repairing or treating volumetric muscle defects.

[0019] In some embodiments, the Sr-Se@SiO2-dECM tissue engineering scaffold promotes vascular regeneration in the repair of volumetric muscle defects.

[0020] Compared with the prior art, the present application combines the nano material Sr-Se@SiO2 with multiple functions of anti-inflammatory response and promoting vascularization, ADSCs with myogenic differentiation potential, and a dECM composite scaffold for loading contents to obtain a composite filling scaffold, which can achieve slow release of Sr and Se and solve the difficulty of vascular regeneration in the repair of volumetric muscle defects. The present application can improve the problems of traditional VML treatment, realize personalized sequential treatment of VML, and provide a new tissue engineering approach for solving the clinical treatment problems of VML. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1The images show the morphology of Sr-Se@SiO2 nanoparticles; A and B are TEM images of Sr-Se@SiO2 nanoparticles, and C is the elemental distribution diagram of Sr-Se@SiO2 nanoparticles.

[0022] Figure 2 The percentages of Se and Sr released from Sr-Se@SiO2 nanoparticles at different times are: A. the percentage of Se released from Sr-Se@SiO2 nanoparticles at different times, and B. the percentage of Sr released from Sr-Se@SiO2 nanoparticles at different times.

[0023] Figure 3 The image shows the preparation and characterization of ADSCs-Sr-Se@SiO2-dECM. Among them, A. the preparation process of micropatterned GelMA gelatin scaffold, B. surface electron microscopy image of GelMA gelatin scaffold loaded with dECM, C. CCK8 determination of the effect of different concentrations of Sr-Se@SiO2 on ADSCs cell viability, D. swelling rate of different scaffold materials, E. mechanical properties of GelMA gelatin scaffold: (1) oscillation frequency (2) oscillation amplitude (3) stress-strain curve.

[0024] Figure 4 To detect the toxicity of co-cultured dECM / Sr-Se@SiO2 with ADSCs; A. Images of live and dead cells after 3 days of co-culture; B. Cell proliferation detected by CCK8 assay after 1, 3, 5, and 7 days of co-culture.

[0025] Figure 5 The effect of dECM / Sr-Se@SiO2 on the myogenic differentiation level of ADSCs was investigated. Among them, A and B were analyzed by immunofluorescence to detect the expression levels and quantification of MYOD, Desmin, and MyHC, while C and D were analyzed by Western blotting to detect the expression levels and quantification of MYOD, MYOG, and Desmin.

[0026] Figure 6 The effects of dECM / Sr-Se@SiO2 on intracellular oxidative stress levels and mitochondrial activity in ADSCs were investigated. A and B involved mitochondrial fluorescent probe staining to detect the number and quantify mitochondria, while C and D involved detecting and quantifying ROS levels in ADSCs one day after H2O2 induction.

[0027] Figure 7 To assess the angiogenesis-promoting effect of dECM / Sr-Se@SiO2; A, B. Transwell assay to detect the migration ability and quantitative analysis of HUVECs after 1 day of co-culture; C, D. Immunofluorescence detection of the expression levels and quantitative analysis of CD31 and VEGF.

[0028] Figure 8 For animal experiments; wherein, A. Establishment of animal model: VML; different components of the material are filled, B. 6 groups of rats tibialis anterior muscle gross specimens after 2 weeks, 4 weeks, 8 weeks.

[0029] Figure 9 For animal experiments; 2 weeks, 4 weeks tibialis anterior muscle H&E staining, Masson staining.

[0030] Figure 10 For immunofluorescence, WB detection of MyHC, CD31 expression level in tissue; wherein, A. 2 weeks immunofluorescence detection of tibialis anterior muscle MyHC, α-SMA, CD31 expression level and quantitative analysis, B. 2 weeks WB detection of tibialis anterior muscle MYOD, CD31 expression level and quantitative analysis. DETAILED DESCRIPTION

[0031] The specific embodiments of the present application are described below with reference to the accompanying drawings. The experimental methods used in the implementation examples are all conventional methods unless otherwise specified; the materials, reagents, etc. used are commercially available unless otherwise specified.

[0032] Example 1 Preparation and characterization detection of Sr-Se@SiO2-dECM

[0033] 1. Preparation of Se@SiO2

[0034] First, 0.3g Se and 15g NaOH were put into 40mL deionized water, heated to 50℃, and stirred until the selenium was completely dissolved. Then 2mL N2H4·H2O, 0.568g CuCl2·2H2O, 2mL oleylamine (OA) were added to the above mixture in turn, and maintained at 100℃ for 2h. After washing with ethanol for 3 times, Cu2-xSe nanoparticles were obtained, and then Cu2-xSe was dispersed in 20mL n-hexane.

[0035] Then, Se@SiO2 nanospheres were prepared by reverse microemulsion method. 0.9mL of deionized water was measured and added to a 100mL single-necked flask, then 3mL of n-hexanol was taken with a pipette and added to the single-necked flask, followed by 3mL of Triton X-100 added to the single-necked flask. 30mL of n-hexane was added to the single-necked flask, and a magnetic stirrer was used for stirring. Then 2mL of the above synthesized copper selenide solution was taken and stirred. After 5min, 0.18mL of tetraethyl orthosilicate (TEOS) was slowly added to the single-necked flask and mixed evenly. After another 5min, 0.18mL of ammonia was slowly added to the single-necked flask, and the solution immediately turned ink blue. Stirring was continued for 24h. After the reaction was completed, the Se@SiO2 nanospheres were prepared by centrifugation with anhydrous ethanol for 3 times (11000r / min, 15min), and finally dispersed in anhydrous ethanol.

[0036] 2. Preparation of Sr-Se@SiO2

[0037] 10 mg of SrCl2·6H2O, 40 mg of Se@SiO2, and 0.1 g of PVP were dissolved in 30 mL of deionized water and stirred for 1 h. Then, 1 mL of ammonia water (30%) was added dropwise, stirred for 10 min, and then the mixed solution was placed in a 50 mL polytetrafluoroethylene reaction kettle and reacted at 140°C in a heating box for 5 h. After washing with deionized water for 3 times, Sr-Se@SiO2 nanoparticles were obtained.

[0038] The morphology of Sr-Se@SiO2 was analyzed by transmission electron microscopy, including size, shape, particle size, distribution, and particle size distribution range. The types of elements, chemical valence, and relative content on the surface of solid materials were studied by an energy dispersive spectrometer.

[0039] Figure 1 A and B are transmission electron microscopy (TEM) images of Sr-Se@SiO2, and the particle size of Sr-Se@SiO2 is about 250 nm. After doping Sr element, the silica shell becomes rough and urchin-like morphology. Figure 1 C is the element distribution map of Sr-Se@SiO2. In the figure, Si, O, and Sr elements are uniformly distributed in the entire nanoparticle, and Se element small particles are scattered in it, indicating that Sr-Se@SiO2 nanoparticles are successfully synthesized.

[0040] 3. Preparation of ADSCs-derived dECM

[0041] Preparation of a mold with an aligned microgroove pattern: A mold with a width of 15 mm, a length of 15 mm, and a height of 20 mm was prepared using 3D printing technology. The linear pattern specifications were a width of 100 μm, a gap of 200 μm, and a depth of 100 μm.

[0042] A 10 wt% Gelma solution was poured into the mold and exposed to ultraviolet light (405 nm, 30 mW / cm 2) and crosslinked under UV irradiation for 5 min. The samples were pre-frozen in a -20 °C freezer for 30 min and then lyophilized in a freeze dryer overnight. Then, the lyophilized samples were swollen in sterile water and stored in a solution containing 1% penicillin and streptomycin in PBS, and irradiated with UV light for 30 min before use. Tissue culture polystyrene (TCPS) plates were pretreated with 0.25% agarose for 1 h at 37 °C and then placed on the patterned Gelma samples. ADSCs were placed on the pretreated plates in growth medium until they reached 90% confluence, and then treated with 100 mM L-ascorbic acid for 7 days. The cell-free ECM was obtained by incubating the cells in extraction buffer (0.5% Triton X-100 and 20 mM NH4OH in PBS, pH 7.4) for 5 min at 37 °C. The ECM was washed three times with PBS to remove residual extraction buffer solution and then stored under sterile conditions at 4 °C.

[0043] The dECM scaffold samples were fixed with 2.5% glutaraldehyde and dehydrated under increasing ethanol concentrations (50%, 75%, 80%, 95%, 100%). Scanning electron microscopy was used for detection.

[0044] 4. Preparation of Sr-Se@SiO2-dECM

[0045] The Sr-Se@SiO2 nanocomposite was uniformly sprayed on the surface of the ADSCs-derived dECM scaffold to form a tissue engineering scaffold with a nanostructure and specific striped grooves. Scanning electron microscopy was used to observe the microstructure of Sr-Se@SiO2 on the surface of the ECM, and to detect the release rate of Sr and Se, the degradation rate of the scaffold material, and the results are shown in Figure 2

[0046] 5. Preparation of ADSCs-containing Sr-Se@SiO2-dECM

[0047] ADSCs were uniformly filled and laid on the surface of the pre-prepared Sr-Se@SiO2-dECM scaffold, and the ADSCs Sr-Se@SiO2-dECM scaffold multilayer was stacked to complete the preparation of the tissue engineering block graft.

[0048] Scanning electron microscopy was used to detect dECM-GelMA, Sr-Se@SiO2-dECM-GelMA, and ADSCs-Sr-Se@SiO2-dECM-GelMA, respectively.

[0049] The results are shown in Figure 3 ​As shown, scanning electron microscopy showed that the dECM-loaded GelMA gelatin scaffold presented a porous structure, which was conducive to the adhesion, proliferation and differentiation of ADCSs on it. The optimal concentration of Sr-Se@SiO2 for cell viability and proliferation of ADSCs was determined to be 20 μg / ml, and this concentration was used in subsequent cell experiments. In addition, the dECM-loaded GelMA gelatin scaffold showed good swelling rate and mechanical properties.

[0050] Example 2: Evaluation of the effect of Sr-Se@SiO2-dECM on cell viability

[0051] Grouping: negative control group, dECM group, Sr-Se@SiO2 group, dECM + Sr-Se@SiO2 group

[0052] Experimental method: CCK8, live and dead cell staining to detect cell viability, detected at 1, 3, 5, and 7 days, respectively.

[0053] Results as shown in Figure 4 Cell viability and cck-8 staining showed that dECM and Sr-Se@SiO2 had no obvious toxicity to ADSCs and could significantly promote the proliferation of ADSCs, and dECM was more effective than Sr-Se@SiO2 in promoting the proliferation of ADSCs.

[0054] Example 3: Evaluation of the effect on the level of myogenic differentiation of ADSCs

[0055] Grouping: negative control group, dECM group, Sr-Se@SiO2 group, dECM + Sr-Se@SiO2 group

[0056] Experimental method: Immunofluorescence, WB to detect the expression levels of MYOD, MYOG, Desmin, MyHC.

[0057] Results as shown in Figure 5 Immunofluorescence and WB detection of the expression levels of myogenic markers (MYOD, MYOG, Desmin, MyHC) showed that dECM and Sr-Se@SiO2 significantly promoted the myogenic differentiation of ADSCs.

[0058] Example 4: Evaluation of the effect on the level of oxidative stress and mitochondrial activity in ADSCs

[0059] Experimental method: fluorescent probe staining to detect the number and activity of mitochondria in cells, intracellular and mitochondrial ROS levels, mitochondrial membrane potential changes; WB to detect antioxidant levels (SOD-1); mitochondrial respiratory chain activity detection; transmission electron microscopy to observe the state of mitochondria in cells; collect ADSCs treated with Sr-Se@SiO2, sequence to further clarify the mechanism of nanocomposite regulating mitochondrial function.

[0060] Results as shown in Figure 6 Mitochondrial red fluorescent probe showed that dECM and Sr-Se@SiO2 could promote the number and activity of mitochondria in ADSCs, and Sr-Se@SiO2 promoted the number and activity of mitochondria more significantly. After inducing the production of ROS in ADSCs with hydrogen peroxide for one day, and then co-culturing with dECM and Sr-Se@SiO2 for 3 days, it was found that dECM and Sr-Se@SiO2 could reduce the production of ROS in ADSCs, and Sr-Se@SiO2 reduced ROS more significantly.

[0061] Example 5 Evaluation of the pro-angiogenic effect of the material

[0062] Grouping: negative control group, dECM group, Sr-Se@SiO2 group, dECM + Sr-Se@SiO2 group

[0063] Experimental method: scratch test, migration test, tube formation analysis; immunofluorescence and WB to detect the expression levels of CD31 and VEGF in human umbilical vein endothelial cells (HUVECs); sequencing to further clarify the mechanism of nanocomposite promoting angiogenesis.

[0064] Results as shown in Figure 7 Transwell test showed that dECM and Sr-Se@SiO2 could significantly promote the migration of human umbilical vein endothelial cells (HUVECs), and immunofluorescence detection of the expression levels of angiogenesis markers (CD31, VEGF) could find that Sr-Se@SiO2 could significantly promote the angiogenesis level of HUVECs, while the angiogenesis ability of dECM was not significant.

[0065] Example 6 Animal experiment

[0066] Grouping: sham operation group, VML group, VML + dECM group, VML + dECM + ADSCs, VML + dECM + Sr-Se@SiO2 group, VML + dECM + ADSCs + Sr-Se@SiO2 group, a total of 45, 5 in each group, fed for 2 weeks, 4 weeks, 8 weeks, and then sampled. Biological function detection, muscle function test, gait analysis, color Doppler observation of lower limb local blood perfusion.

[0067] As Figure 8 shown, Figure A shows the establishment of VML animal model. The rat tibialis anterior muscle (TA) is surgically resected to form a muscle defect area of about 10 mm x 7 mm x 3 mm (length x width x depth), and the corresponding scaffold material containing ADSCs and Sr-Se@SiO2 in the treatment group is implanted. Figure B shows the general observation of the rat TA specimen obtained after 2 weeks, 4 weeks and 8 weeks of modeling. It can be found that the muscle tissue at the defect site basically recovers after 8 weeks of modeling.

[0068] Example 7 tissue section staining

[0069] HE staining is used to observe the cross-sectional area of muscle fibers and blood vessel regeneration, and Masson staining is used to observe the distribution of fibrous connective tissue and new muscle fibers.

[0070] As Figure 9 shown, HE staining shows that after 2 weeks and 4 weeks of modeling, the cross-sectional area and number of regenerated muscle fibers are obviously improved when dECM scaffold, ADSCs and Sr-Se@SiO2 exist at the same time. Masson staining shows that the area of fibrous connective tissue is obviously reduced when dECM scaffold, ADSCs and Sr-Se@SiO2 exist at the same time, and more new capillary blood vessels are formed (black arrow position) when Sr-Se@SiO2 is loaded.

[0071] Example 8 analysis of tissue myogenic and angiogenic levels

[0072] Immunofluorescence and WB are used to detect the expression levels of MyHC and CD31 in the tissue.

[0073] As Figure 10 shown, the expression levels of myogenic markers (MYOD, MyHC) and angiogenic markers (CD31, a-SMA) are analyzed by immunofluorescence and WB, and it is found that the muscle and blood vessel regeneration after muscle tissue defect is promoted when dECM scaffold, ADSCs and Sr-Se@SiO2 exist at the same time.

[0074] Although the present application has been disclosed with reference to the preferred embodiments above, it is not intended to limit the present application, and any person skilled in the art can make various modifications and modifications without departing from the spirit and scope of the present application, therefore the protection scope of the present application should be defined by the claims.

Claims

1. A method for preparing a Sr-Se@SiO2-dECM tissue engineering scaffold, characterized in that, The preparation method includes the following steps: Step 1: Prepare Se@SiO2 nanoparticles using the reverse microemulsion method; Step 2: Dissolve the Se@SiO2 nanoparticles obtained in Step 1 with SrCl2·6H2O and PVP in deionized water and stir until homogeneous. Add ammonia dropwise, stir, and place in a polytetrafluoroethylene reactor. React at 130-150℃ for 4-6 hours. Wash with deionized water to obtain Sr-Se@SiO2 nanoparticles. Step 3: Place the Gelma sample in a pretreated tissue culture polystyrene plate, and simultaneously place ADSCs into the tissue culture polystyrene plate. Add growth medium and culture until the ADSCs fuse with the Gelma sample. Then add ascorbic acid for 6-8 days to obtain ADSCs loaded on gelatin sheets. Step 4: Place the ADSCs obtained in Step 3 in the extraction buffer and incubate for 3-8 minutes, then fix with glutaraldehyde to obtain dECM derived from ADSCs. Step 5: Uniformly spray the Sr-Se@SiO2 nanoparticles obtained in Step 3 onto the ADSCs-derived dECM obtained in Step 4 to obtain the Sr-Se@SiO2-dECM tissue engineering scaffold with nanostructure.

2. The preparation method according to claim 1, characterized in that, Step 1 includes the following steps: adding hexanol, Triton X-100, and hexane to deionized water and stirring until homogeneous; adding copper selenide solution and stirring for 3-5 minutes; adding tetraethyl orthosilicate and stirring for 3-5 minutes; adding ammonia water to make the solution dark blue; stirring for 20-28 hours; and then washing with anhydrous ethanol by centrifugation to obtain the final product.

3. The preparation method according to claim 2, characterized in that, The volume ratio of n-hexanol, Triton X-100, and n-hexane is 1:1:10, the volume ratio of copper selenide solution to n-hexanol is 3:2, and the volume ratio of copper selenide solution to tetraethyl orthosilicate is 10-12:

1.

4. The preparation method according to claim 2, characterized in that, The preparation method of the copper selenide solution includes: placing Se and NaOH in deionized water, heating to 45-55℃, stirring until the selenium is completely dissolved, then adding N2H4·H2O, CuCl2·2H2O, and 2 mL of oleylamine (OA) sequentially to the mixed solution, maintaining at 80-120℃ for 2-5 h, washing with ethanol 2-4 times to obtain Cu2-xSe nanoparticles, and then dispersing Cu2-xSe in n-hexane.

5. The preparation method according to claim 1, characterized in that, The mass ratio of Se@SiO2 nanoparticles to SrCl2·6H2O is 1:3-5, the mass ratio of Se@SiO2 nanoparticles to PVP is 95-105:1, the mass-volume ratio of Se@SiO2 nanoparticles to ammonia (25%-30%) is 20-80 mg:1 mL, the reaction temperature in the polytetrafluoroethylene reactor is 120-160℃, and the reaction time is 2-8 h.

6. The preparation method according to claim 1, characterized in that, The method for preparing the Gelma sample includes pouring a 5-15 wt% Gelma solution into a mold, exposing it to ultraviolet light for cross-linking to obtain a sample, and then freeze-drying the sample overnight to obtain the Gelma sample.

7. The Sr-Se@SiO2-dECM tissue engineering scaffold prepared by any one of the preparation methods described in claims 1-6.

8. The use of the Sr-Se@SiO2-dECM tissue engineering scaffold according to claim 7 in the repair or treatment of volumetric muscle defects.

9. The application according to claim 8, characterized in that, The Sr-Se@SiO2-dECM tissue engineering scaffold promotes angiogenesis in the repair of volumetric muscle defects.

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