Platinum nano-particles and application of platinum nano-particles and adipose-derived stem cells in adipose transplantation

Abstract

The invention discloses platinum nano-particles and application of the platinum nano-particles and adipose-derived stem cells in adipose transplantation. The platinum nanoparticles can remove active oxygen in stem cells, improve the oxidation resistance of the stem cells, improve the proliferation ability of the stem cells, improve the adipogenesis ability of the stem cells, improve the vascularization ability of the stem cells, and up-regulate the expression level of vascularization related factors Vegf and Fgf2; and the fat stem cells pretreated by the platinum nanoparticles are added into the fat graft, so that the general form and histological form of the fat graft can be effectively improved. The platinum nanoparticles have the characteristics of stable property, lasting effect and the like, and the application effect of the adipose-derived stem cells in adipose transplantation can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of biomedicine, and in particular to a platinum nanoparticle and an application of the platinum nanoparticle in combination with adipose stem cells in fat transplantation. Background Art

[0002] Tissue deformities and defects caused by inflammation, trauma, tumors or congenital malformations can seriously affect patients' oral function and facial appearance, and thus affect their quality of life and physical and mental health. At present, the main method of clinical practice is to restore the patient's facial contour through autologous fat transplantation. However, studies have shown that most patients have varying degrees of fat absorption after surgery, and may even develop complications such as fat necrosis and calcification, making the long-term effects of surgery unpredictable and difficult to achieve the ideal aesthetic effect.

[0003] In recent years, stem cell-based regenerative medicine strategies have provided an effective treatment for this problem. Adipose-derived stem cells are a type of mesenchymal stem cells that have multidirectional differentiation potential and can secrete a variety of cytokines. They also have the advantages of a wide range of sources and easy separation, and have great application prospects in regenerative medicine. Studies have shown that adipose stem cell-assisted fat transplantation technology, that is, adding adipose stem cells to fat transplants, can effectively improve the survival rate of adipose tissue. However, some studies have pointed out that the stem cell properties of mesenchymal stem cells are affected by various factors in the microenvironment, which in turn affects their effects. Among them, oxidative stress caused by the accumulation of reactive oxygen species is an important factor in damaging stem cell performance. Reactive oxygen is a class of highly reactive oxygen-containing substances, including peroxides, superoxides, hydroxyl radicals, etc., which are natural byproducts of cell metabolism. Under physiological conditions, the endogenous antioxidant system of cells can maintain the homeostasis of reactive oxygen. However, in practical applications, stem cells often need to be expanded in vitro to reach the required number. During this process, reactive oxygen species continue to accumulate. When their content exceeds the clearance capacity of the cell's endogenous antioxidant system, it will induce oxidative stress, thereby damaging important cellular components such as DNA, proteins, and lipids. At the same time, it will affect cell signal transduction, leading to cell dysfunction and even apoptosis, thereby damaging the performance of mesenchymal stem cells and seriously affecting their role in tissue regeneration.

[0004] Therefore, clearing the excessive accumulation of reactive oxygen species in mesenchymal stem cells and maintaining the redox homeostasis of mesenchymal stem cells are effective strategies to improve their stem cell performance and enhance their application effects. Studies have shown that supplementing exogenous antioxidants such as glutathione, melatonin, and vitamin C can effectively reduce the level of intracellular reactive oxygen species and improve stem cell performance. However, most organic antioxidants have problems such as short action time, difficulty in local application, and difficulty in reaching effective concentrations for systemic application, and their clinical application is still limited. Therefore, it is of great significance to explore a new exogenous antioxidant to improve the antioxidant, proliferation, adipogenic differentiation, and angiogenic differentiation capabilities of adipose stem cells and improve the survival rate of adipose tissue in fat transplantation. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a platinum nanoparticle and its application in fat transplantation in combination with adipose stem cells.

[0006] In a first aspect, the present invention provides multiple uses of platinum nanoparticles, which are achieved according to the following technical solutions.

[0007] Use of platinum nanoparticles in preparing any of the following preparations:

[0008] a. Prepare inhibitors of reactive oxygen species and their products in stem cells;

[0009] b. preparing a stem cell proliferation promoter;

[0010] c. preparing an agent to promote adipogenic differentiation of stem cells;

[0011] d. preparing angiogenic differentiation promoters in stem cells;

[0012] e. preparing angiogenesis-related factors Fgf2 and Vegf expression activators in stem cells;

[0013] f. Preparation of an agent for improving the survival rate of adipose tissue in fat transplantation.

[0014] Furthermore, the concentration of the platinum nanoparticles is 2.5-10 μg / mL. Preferably, the concentration of the platinum nanoparticles is 5 μg / mL.

[0015] Furthermore, the stem cells are selected from mesenchymal stem cells, and the mesenchymal stem cells are selected from adipose-derived mesenchymal stem cells. Specifically, the adipose-derived mesenchymal stem cells are derived from inguinal adipose tissue of 8-week-old male C57BL / 6 mice; the adipose-derived mesenchymal stem cells are cultured in vitro, the in vitro culture is adherent culture, and the cells are subcultured for 6-9 generations.

[0016] Furthermore, the preparation method of the platinum nanoparticles is as follows:

[0017] S1. Stir and mix chloroplatinic acid hexahydrate solution and deionized water at room temperature in a volume ratio of 1:10-1:40;

[0018] S2. Mix Tween 20 and sodium borohydride solution in a volume ratio of 1:50-1:200, and add the mixed solution in a volume ratio of 1:10-1:40 to the solution prepared in step S1, and stir in dark for 1-6 hours;

[0019] S3. Centrifuge at 2000g-8000g for 10-60 minutes and collect the precipitate, which is the platinum nanoparticles.

[0020] In a second aspect, the present invention provides a promoter for improving the antioxidant, proliferation, adipogenesis and angiogenesis abilities of mouse adipose stem cells, which is achieved according to the following technical scheme.

[0021] A promoter for improving the antioxidant, proliferation, adipogenesis and angiogenesis capabilities of mouse adipose stem cells, comprising platinum nanoparticles with a concentration of 2.5-10 μg / mL.

[0022] In a third aspect, the present invention provides a combined use of platinum nanoparticles and adipose stem cells, which is achieved according to the following technical scheme.

[0023] A method of combining platinum nanoparticles with adipose stem cells for preparing a reagent for improving the survival rate of adipose tissue in fat transplantation.

[0024] Furthermore, adipose stem cells were pretreated with platinum nanoparticles at a concentration of 2.5-10 μg / mL.

[0025] Furthermore, the cell concentration of pretreated adipose-derived stem cells was 1×10 4 -5×10 4 cells / 100 μL adipose tissue.

[0026] In a fourth aspect, the present invention provides a reagent for improving the survival rate of adipose tissue in fat transplantation, which is achieved according to the following technical scheme.

[0027] A reagent for improving the survival rate of adipose tissue in fat transplantation, comprising platinum nanoparticles with a concentration of 2.5-10 μg / mL, and a volume ratio of the platinum nanoparticle solution to the adipose tissue homogenate of 1:20-1:40.

[0028] Furthermore, the invention also includes adipose-derived stem cells, wherein the cell concentration of adipose-derived stem cells treated with 2.5-10 μg / mL platinum nanoparticles is 1×10 4 -5×10 4 cells / 100 μL adipose tissue.

[0029] In a fifth aspect, the present invention provides a method for improving the proliferation ability of stem cells, which is achieved by adopting the following technical solution.

[0030] A method for improving stem cell proliferation ability comprises the following steps:

[0031] 1) Obtain and purify stem cells;

[0032] 2) Cultivating stem cells using a culture medium containing platinum nanoparticles for more than 2 days.

[0033] In a sixth aspect, the present invention provides a method for improving the adipogenic ability of stem cells, which is achieved by adopting the following technical scheme.

[0034] A method for improving the adipogenic ability of stem cells, comprising the following steps:

[0035] 1) Obtain and purify stem cells;

[0036] 2) The stem cells are cultured using an adipogenic induction solution containing platinum nanoparticles and the culture is continued for more than 2 days.

[0037] Specifically, the adipogenic induction solution uses mouse adipose-derived mesenchymal stem cell adipogenic differentiation medium (Punosai, Wuhan, China), including:

[0038] Mouse adipose-derived mesenchymal stem cell adipogenic differentiation medium ADP1: 1% glutamine, 1% penicillin-streptomycin, 0.2% insulin, 0.1% IBMX, 0.1% rosiglitazone, 0.1% dexamethasone, 10% fetal bovine serum, and the rest is mouse adipose-derived mesenchymal stem cell adipogenic differentiation basal medium ADP1;

[0039] Mouse adipose-derived mesenchymal stem cell adipogenic differentiation medium ADP2 (maintenance medium): 1% glutamine, 1% penicillin-streptomycin, 0.2% insulin, 10% fetal bovine serum, and the rest is mouse adipose-derived mesenchymal stem cell adipogenic differentiation basal medium ADP2.

[0040] In a seventh aspect, the present invention provides a method for improving the angiogenesis ability of stem cells, which is achieved by adopting the following technical solution.

[0041] 1) Obtain and purify stem cells;

[0042] 2) Cultivating stem cells using a culture medium containing platinum nanoparticles for more than 2 days.

[0043] In an eighth aspect, the present invention provides a method for removing active oxygen in stem cells, which is achieved by adopting the following technical solution.

[0044] A method for removing active oxygen in stem cells, comprising the following steps:

[0045] 1) Obtain and purify stem cells;

[0046] 2) Cultivating stem cells using a culture medium containing platinum nanoparticles for more than 2 days.

[0047] In a ninth aspect, the present invention provides a fat transplantation method for improving the gross morphology and histological morphology of the graft, which is achieved by adopting the following technical scheme.

[0048] A fat transplantation method for improving the gross morphology and histological morphology of the transplant comprises the following steps:

[0049] 1) Extract an appropriate volume of adipose tissue, chop it into small pieces, and prepare adipose tissue homogenate;

[0050] 2) Add 2.5-10 μg / mL platinum nanoparticle solution to adipose tissue homogenate, with the volume ratio of platinum nanoparticle solution to adipose tissue homogenate being 1:20-1:40, and mix well; or after culturing adipose stem cells with 2.5-10 μg / mL platinum nanoparticle solution, collect the cells and 4 -5×10 4 Add the cells / 100 μL of adipose tissue homogenate into the adipose tissue homogenate and mix well;

[0051] 3) injecting the adipose tissue homogenate into the transplantation site and distributing it evenly;

[0052] 4) Close the wound and wait for the fat graft to take root.

[0053] The advantages and beneficial effects of the present invention are:

[0054] 1. After the mouse adipose stem cells were cultured in a culture medium containing platinum nanoparticles, no cytotoxic effects were observed, the level of intracellular reactive oxygen species decreased, and the levels of proliferation, adipogenesis, and angiogenesis increased. Therefore, platinum nanoparticles can be used to prepare antioxidant, proliferation, adipogenesis, and angiogenesis promoters for mouse adipose stem cells.

[0055] 2. The present invention adds an effective concentration of platinum nanoparticles / an effective number of adipose stem cells treated with platinum nanoparticles to the fat graft, which has good biocompatibility, can promote the survival of the fat graft, and improve its gross morphology and histological morphology. Moreover, platinum nanoparticles have the characteristics of stable properties and long-lasting effects. Therefore, adding platinum nanoparticles / pre-treating adipose stem cells with platinum nanoparticles can be used as a new method to improve the application effect of adipose stem cells in fat transplantation. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1The effects of different concentrations of platinum nanoparticles of the present invention on the activity of adipose stem cells (wherein A. Schematic diagram of cell activity; B. Ratio of early apoptotic cells; C. Ratio of late apoptotic cells; D. Ratio of live cells);

[0057] Figure 2 The effects of different concentrations of platinum nanoparticles of the present invention on the proliferation capacity of adipose stem cells (wherein A. Ki67 immunofluorescence staining schematic diagram; B. Ki67 immunofluorescence quantitative analysis diagram; C. PCNA mRNA relative expression level);

[0058] Figure 3 The effects of different concentrations of platinum nanoparticles of the present invention on adipogenic differentiation of adipose stem cells (A. Oil Red O staining schematic diagram; B. Oil Red O staining quantitative analysis diagram);

[0059] Figure 4 The effects of different concentrations of platinum nanoparticles of the present invention on the angiogenic differentiation of adipose stem cells (A. Relative mRNA expression of Vegf; B. Relative mRNA expression of Fgf2);

[0060] Figure 5 The effects of different concentrations of platinum nanoparticles of the present invention on the reactive oxygen species of adipose stem cells (wherein A. Schematic diagram of fluorescence staining of total reactive oxygen species in cells; B. Schematic diagram of fluorescence quantitative analysis of total reactive oxygen species in cells);

[0061] Figure 6 The morphology of the fat grafts added with platinum nanoparticles, adipose-derived stem cells, and adipose-derived stem cells pretreated with platinum nanoparticles 8 weeks after surgery (wherein A. the imaging morphology of the fat graft; B. the gross morphology of the fat graft; C. the quality of the fat graft);

[0062] Figure 7 The histological morphology of the fat transplants added with platinum nanoparticles, adipose stem cells, and adipose stem cells pretreated with platinum nanoparticles of the present invention 8 weeks after surgery (wherein A. HE staining schematic diagram; B. immunohistochemical staining schematic diagram of angiogenesis-related factor CD31; C. fluorescent staining schematic diagram of perilipin protein). DETAILED DESCRIPTION

[0063] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0064] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the materials, reagents, etc. used in the following preparation examples and examples, unless otherwise specified, can be obtained from commercial channels.

[0065] 1. Main experimental materials

[0066] The preparation method of platinum nanoparticle solution (PtNPs) is as follows: add 1mL 38.6mmol / L hexahydrate chloroplatinic acid solution to 20mL deionized water and mix it with a magnetic stirrer at room temperature. Quickly add 10μL Tween 20 and 1mL 18.92mg / mL sodium borohydride solution, stir for 3 hours in the dark. Centrifuge at 2000g for 20 minutes and 8000g for 20 minutes, and collect the black precipitate as platinum nanoparticles. After washing it with ultrapure water, add it to deionized water, filter it under sterile conditions, seal it at 4℃ and store it in the dark. When using it, add it to the culture medium and adjust the final concentration to 2.5-10μg / mL. The culture medium includes 10% fetal bovine serum, 1% penicillin and streptomycin, and the rest is α-MEM culture medium.

[0067] Adipose-derived mesenchymal stem cells (ADSCs) were obtained from the inguinal adipose tissue of C57BL / 6 mice with approval from the Ethics Committee of Tianjin Medical University;

[0068] C57BL / 6 mice were purchased from Beijing Sibeifu Biotechnology Co., Ltd.

[0069] 2. Grouping

[0070] The cells were divided into groups according to the concentration of platinum nanoparticles added in the culture medium or induction medium: ① 0 μg / mL group (blank group); ② 2.5 μg / mL group; ③ 5 μg / mL group; ④ 10 μg / mL group.

[0071] After mouse mesenchymal stem cells were extracted and purified, they were inoculated in the above-mentioned culture medium environment containing different concentrations of platinum nanoparticles and cultured in an incubator at 37° C. and 5% CO 2 .

[0072] 3. Experimental process and results

[0073] 1. Cell Viability Detection

[0074] Mouse adipose-derived stem cells were seeded in a 96-well plate at a density of 2000 cells / well, and culture medium containing different concentrations of platinum nanoparticles was added. After culturing for 24 hours, 48 ​​hours, and 72 hours, the original culture medium was removed, and the plates were washed three times with PBS, and 10 μL / well of CCK-8 detection solution and 100 μL / well of culture medium without platinum nanoparticles were added. After culturing in an incubator in the dark for 2 hours, the absorbance at 450 nm was measured with an enzyme marker.

[0075] The experimental results are as follows Figure 1 As shown in A, compared with the 0 μg / mL group, the proliferation activity of adipose stem cells treated with 2.5 μg / mL, 5 μg / mL and 10 μg / mL platinum nanoparticles was significantly increased (p < 0.05), with the effect of 5 μg / mL being the most significant.

[0076] 2. Cell Apoptosis Detection

[0077] Mouse adipose stem cells were seeded in a six-well plate at a density of 500,000 to 1,000,000 cells / well, and culture medium containing platinum nanoparticles at different concentrations was added for culture. After 4 days, the original culture medium was removed, the cells were washed with PBS 3 times, trypsin was added for digestion, the cells were collected, washed with cold PBS 2 times, and the cells were resuspended in staining buffer to adjust the concentration to 1,000,000 cells / mL. The cells were added to 1 mL of pre-cooled ethanol to a final concentration of 70%, incubated at 4°C overnight, centrifuged at 1000 g for 5 minutes, the fixative was removed, the cells were washed with cold PBS once, 0.5 mL of the prepared propidium iodide staining solution was added, and the cells were incubated at 37°C in the dark for 1 hour, and detected by flow cytometer at an excitation wavelength of 488 nm.

[0078] The experimental results are as follows Figure 1 As shown in Figures 1B, 1C, and 1D, compared with the 0 μg / mL group, there was no significant change in the early apoptosis, late apoptosis, and proportion of live cells of adipose stem cells treated with 2.5 μg / mL, 5 μg / mL, and 10 μg / mL platinum nanoparticles, indicating that the above-mentioned various concentrations of platinum nanoparticles had no obvious promoting effect on the apoptosis of adipose stem cells and had good cell compatibility.

[0079] 3. Cell proliferation detection

[0080] Mouse adipose-derived stem cells were seeded on a cell slide in a 24-well plate at a density of 10,000 cells / well, and cultured with culture medium containing different concentrations of platinum nanoparticles. When the confluence reached 70%-80%, the original culture medium was removed, 4% paraformaldehyde was added for fixation at room temperature for 15 minutes, washed 3 times with PBS, 0.2% Triton X-100 cell permeabilization solution was added for 10 minutes, washed 3 times with PBS, blocked with 1% bovine serum albumin for 1 hour, Ki-67 primary antibody and secondary antibody were added for incubation in the dark for 3 hours and 1 hour respectively, and the nuclei were stained with the nuclear dye DAPI in the dark for 10 minutes. Images were collected using a laser confocal microscope. Mouse adipose stem cells were seeded into six-well plates at a density of 500,000 to 1,000,000 cells / well and cultured in culture medium containing different concentrations of platinum nanoparticles. The original culture medium was removed after 6 days, and the cells were washed three times with PBS. Total cell RNA was collected according to the Trizol method, and β-actin was used as an internal reference. Real-time fluorescence quantitative PCR technology was used to quantify the expression of cell proliferation-related factors according to the instructions of the full-length gold reverse transcription kit and the fluorescence quantitative kit.

[0081] The experimental results are as follows Figure 2 As shown in A and 2B, compared with the 0 μg / mL group, the Ki-67 fluorescence intensity and positive rate of adipose stem cells treated with 2.5 μg / mL, 5 μg / mL, and 10 μg / mL platinum nanoparticles were higher, indicating that platinum nanoparticles promoted the expression of Ki-67. Figure 2As shown in Figure C, compared with the 0 μg / mL group, the relative expression of PCNA mRNA in adipose stem cells treated with 2.5 μg / mL, 5 μg / mL and 10 μg / mL platinum nanoparticles increased significantly. The above results suggest that platinum nanoparticles can promote the proliferation of adipose stem cells.

[0082] 4. Adipogenic Differentiation Assay

[0083] Mouse adipose-derived stem cells were inoculated into six-well plates at a density of 300,000 cells / well, and cultured with complete culture medium containing different concentrations of platinum nanoparticles. When the degree of confluence reached 90%-100%, the original culture medium was removed, and mouse adipose-derived mesenchymal stem cell adipogenic differentiation medium ADP1 was added to continue culture. After 3 days of induction, ADP1 was removed, and mouse adipose-derived mesenchymal stem cell adipogenic differentiation medium ADP2 (maintenance medium) was added. After 1 day of culture, it was replaced with ADP1 for induction for 3 days. After alternating induction with ADP1-ADP2 culture medium for 3 times, obvious lipid droplets were observed in the stem cells. ADP2 was used to maintain culture for 3 days until the lipid droplets were full, the original culture medium was removed, PBS was washed twice, 4% paraformaldehyde was added for fixation for 30 minutes, the fixative was removed, PBS was washed twice, 1 mL of Oil Red O working solution was added to each well, and the cells were stained at room temperature for 30 minutes. The staining solution was removed, PBS was washed twice, and the cells were observed under an inverted microscope.

[0084] The experimental results are as follows Figure 3 As shown in A and 3B, compared with the 0 μg / mL group, the Oil Red O staining intensity of adipose stem cells treated with 2.5 μg / mL, 5 μg / mL and 10 μg / mL platinum nanoparticles increased significantly, indicating that platinum nanoparticles can promote the adipogenic differentiation of adipose stem cells.

[0085] 5. Angiogenic Differentiation Assay

[0086] Mouse adipose-derived stem cells were seeded into six-well plates at a density of 500,000 to 1,000,000 cells / well and cultured in culture medium containing different concentrations of platinum nanoparticles for 6 days. Total cell RNA was collected as described above, and the expression of angiogenesis-related factors was quantified using real-time fluorescence quantitative PCR technology.

[0087] The experimental results are as follows Figure 4 As shown in A and 4B, compared with the 0 μg / mL group, the relative mRNA expression levels of Vegf and Fgf2 in adipose stem cells treated with 2.5 μg / mL, 5 μg / mL and 10 μg / mL platinum nanoparticles increased significantly, indicating that platinum nanoparticles can promote the angiogenic differentiation of adipose stem cells.

[0088] 6. Cellular Reactive Oxygen Species Detection

[0089] Mouse adipose stem cells were inoculated into six-well plates at a density of 500,000-1,000,000 cells / well, cultured with culture medium containing platinum nanoparticles at different concentrations for 4 days, the original culture medium was removed, the plates were washed three times with PBS, and 10 μmol / L DCFH-DA cell reactive oxygen species probe was added at 1 mL / well. The plates were cultured in the dark at 37°C for 25 minutes, washed three times with serum-free α-MEM culture medium, and the total ROS fluorescence intensity of the cells was observed and detected using a laser confocal microscope at an excitation wavelength of 488 nm and an emission wavelength of 525 nm.

[0090] The experimental results are as follows Figure 5 As shown in A and 5B, compared with the 0 μg / mL group, the total ROS fluorescence intensity of adipose stem cells treated with 2.5 μg / mL, 5 μg / mL, and 10 μg / mL platinum nanoparticles was weakened, indicating that platinum nanoparticles can effectively remove reactive oxygen species in adipose stem cells.

[0091] 7. Sixteen 6-week-old male C57 mice were randomly divided into the CON group, PtNPs group, ADSCs group and PtNPs pre-treated ADSCs group. After 3% isoflurane anesthesia, the inguinal fat of the mice was separated and cut into pieces to obtain fat grafts. The fat grafts of the CON group, PtNPs group, ADSCs group and PtNPs pre-treated ADSCs group were added with 10 μL PBS, 10 μL PtNPs, 10 μL ADSCs suspension and 10 μL ADSCs suspension treated with 5 μg / mL PtNPs, respectively, and mixed. Among them, the cell concentration of the ADSCs group and the PtNPs pre-treated ADSCs group was 1×10 4 cells / 100 μL adipose tissue. Subsequently, the fat grafts with different treatments were injected into the top area of ​​the mouse head using a syringe, with 300 μL for each mouse. The mice were grouped and fed with normal food and water. At 8 weeks after surgery, the mice were anesthetized with 3% isoflurane and scanned with the SkyScan 1276 μCT machine from Bruker, with a 10 μm pixel volume and 55 kV voltage parameters. The CTvox software from Bruker was used for 3D reconstruction, and the 3D cross-sectional images were obtained with the DataViewer software from Bruker.

[0092] The experimental results are as follows Figure 6 As shown in A and 6B, at 8 weeks after fat transplantation, the fat graft volume in the PtNPs group, ADSCs group, and PtNPs pre-treated ADSCs group was larger than that in the CON group, and the PtNPs pre-treated ADSCs group was more significant. Figure 6 As shown in C, compared with the CON group, the fat graft mass in the PtNPs group, ADSCs group and PtNPs pretreated ADSCs group was larger, and the difference was more significant in the PtNPs pretreated ADSCs group.

[0093] 8. Modeling As described above, at 8 weeks after surgery, mice were killed after anesthesia with 3% isoflurane overdose, and fat graft samples were isolated and fixed in 4% paraformaldehyde fixative for 2 days. After paraffin embedding, they were cut into 4 μm tissue sections with a microtome, and hematoxylin-eosin, CD31 and Perilipin immunofluorescence staining were performed according to the standard procedures of Fancovi, and observed under a microscope.

[0094] The experimental results are as follows Figure 7 As shown in A, compared with the CON group, the integrity of the fat grafts in the PtNPs group, ADSCs group, and PtNPs pre-treated ADSCs group was higher and the number of vacuoles was less, which was more significant in the PtNPs pre-treated ADSCs group. Figure 7 As shown in B, compared with the CON group, the number of CD31-positive blood vessels in the fat grafts of the PtNPs group, ADSCs group, and PtNPs pre-treated ADSCs group was greater, and the PtNPs pre-treated ADSCs group was more significant. Figure 7 As shown in C, compared with the CON group, there were more perilipin-positive adipocytes in the fat grafts of the PtNPs group, ADSCs group and PtNPs pre-treated ADSCs group, and this was more significant in the PtNPs pre-treated ADSCs group.

[0095] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. Use of platinum nanoparticles in the preparation of any of the following preparations: a. Prepare inhibitors of reactive oxygen species and their products in stem cells; b. preparing a stem cell proliferation promoter; c. preparing an agent to promote adipogenic differentiation of stem cells; d. preparing angiogenic differentiation promoters in stem cells; e. preparing angiogenesis-related factors Fgf2 and Vegf expression activators in stem cells; f. Preparation of an agent for improving the survival rate of adipose tissue in fat transplantation.

2. The use according to claim 1, characterized in that: The concentration of the platinum nanoparticles is 2.5-10 μg / mL.

3. The use according to claim 1, characterized in that: The stem cells are mesenchymal stem cells, and the mesenchymal stem cells are adipose-derived mesenchymal stem cells.

4. The use according to claim 1, characterized in that: The preparation method of the platinum nanoparticles is as follows: S1. Stir and mix chloroplatinic acid hexahydrate solution and deionized water at room temperature in a volume ratio of 1:10-1:40; S2. Mix Tween 20 and sodium borohydride solution in a volume ratio of 1:50-1:200, and add the mixed solution in a volume ratio of 1:10-1:40 to the solution prepared in step S1, and stir in dark for 1-6 hours; S3. Centrifuge at 2000g-8000g for 10-60 minutes and collect the precipitate, which is the platinum nanoparticles.

5. A promoter for improving the antioxidant, proliferation, adipogenesis and angiogenesis abilities of mouse adipose stem cells, characterized in that: Includes platinum nanoparticles at a concentration of 2.5-10 μg / mL.

6. A reagent for improving the survival rate of adipose tissue in fat transplantation, characterized in that: The platinum nanoparticles have a concentration of 2.5-10 μg / mL, and the volume ratio of the platinum nanoparticle solution to the adipose tissue homogenate is 1:20-1:

40.

7. The reagent according to claim 6, characterized in that: Adipose-derived stem cells were also included. The cell concentration of adipose-derived stem cells treated with 2.5-10 μg / mL platinum nanoparticles was 1×10 4 -5×10 4 cells / 100 μL adipose tissue.

8. Use of platinum nanoparticles in combination with adipose stem cells for preparing a reagent for improving the survival rate of adipose tissue in fat transplantation.

9. The use according to claim 8, characterized in that: Adipose-derived stem cells were pretreated with platinum nanoparticles at a concentration of 2.5-10 μg / mL.

10. The use according to claim 9, characterized in that: The cell concentration of pretreated adipose-derived stem cells was 1×10 4 -5×10 4 cells / 100 μL adipose tissue.

Images