Medical dressing for promoting healing of diabetic wound and preparation method thereof

Abstract

The invention relates to the technical field of medicines, in particular to a medical dressing for promoting healing of a diabetic wound and a preparation method of the medical dressing. The medical dressing for promoting healing of the diabetic wound surface is prepared from the following raw materials in percentage by mass: 0.008 to 0.012 percent of stem cell exosome, 0.002 to 0.005 percent of oligopeptide-1, 0.004 to 0.01 percent of jasminin, 0.03 to 0.07 percent of modified CaSi2 nanosheets, 2 to 6 percent of hydroxypropyl chitosan, 0.1 to 0.5 percent of xanthan gum, 0.5 to 5 percent of glycerol and the balance of water. The medical dressing not only can promote wound healing, but also is beneficial to scar repair after wound healing.

Description

Technical Field

[0001] The invention relates to the technical field of medicine, and in particular to a medical dressing for promoting healing of diabetic wounds and a preparation method thereof. Background Art

[0002] Acute or chronic wounds caused by diabetes are slow to heal and are prone to various complications, placing a heavy burden on patients, the medical system, and the social economy. Since diabetic patients are prone to vascular lesions, vascular regeneration is impaired, which in turn hinders cell proliferation and the synthesis and remodeling of the extracellular matrix, ultimately leading to the formation of chronic, difficult-to-heal wounds. Promoting angiogenesis is considered to be one of the key factors in treating diabetic wounds.

[0003] Exosomes are bilayer lipid vesicles with a diameter of 30-150nm secreted by cells through the multivesicular body pathway. They contain a variety of biologically active molecules such as proteins, microRNAs, and long non-coding RNAs, and play an important role in intercellular material transport and signal communication. Stem cell exosomes can promote endothelial cell proliferation, migration, and microtubule formation, thereby stimulating angiogenesis. However, after adding stem cell exosomes to dressings, there are problems with reduced stability and activity, which limits their application in medical dressings. In addition, the difficult healing characteristics of diabetic wounds often lead to more scars after wound healing, affecting the aesthetics of the skin, and existing dressings cannot effectively reduce the formation of scars at diabetic wounds. Therefore, it is necessary to improve existing dressings to solve the above problems. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, one of the purposes of the present invention is to provide a medical dressing for promoting the healing of diabetic wounds, which can not only promote wound healing, but also facilitate the repair of scars after wound healing.

[0005] The second object of the present invention is to provide a method for preparing a medical dressing for promoting healing of diabetic wounds, which has simple steps and is easy to operate.

[0006] One of the purposes of the present invention is achieved by the following technical solution: A medical dressing for promoting healing of diabetic wounds comprises the following raw materials, measured by mass percentage: 0.008-0.012% of stem cell exosomes, 0.002-0.005% of oligopeptide-1, 0.004-0.01% of jasmine, 0.03-0.07% of modified CaSi2 nanosheets, 2-6% of hydroxypropyl chitosan, 0.1-0.5% of xanthan gum, 0.5-5% of glycerol, and the balance being water.

[0007] Furthermore, the preparation process of the modified CaSi2 nanosheets is as follows: The CaSi2 nanosheets are added into the phytic acid solution for reaction, and purified after the reaction is completed to obtain the product.

[0008] Furthermore, the dosage ratio of the CaSi2 nanosheets and the phytic acid solution is 1 g: (180-200) mL; the concentration of the phytic acid solution is 0.4-0.5 mol / L.

[0009] Furthermore, the reaction temperature is 35-45° C., and the reaction time is 0.5-1.5 h.

[0010] Furthermore, the preparation process of the CaSi2 nanosheets is: dispersing CaSi2 powder in N-methyl-2-pyrrolidone, performing probe ultrasonic treatment under ice bath conditions to collect the precipitate and washing and drying the precipitate.

[0011] Furthermore, the dosage ratio of the CaSi2 powder and N-methyl-2-pyrrolidone is 1 g: (45-55) mL; and the probe ultrasonic treatment time is 10-12 h.

[0012] Furthermore, the stem cell exosomes are umbilical cord mesenchymal stem cell exosomes.

[0013] Furthermore, the umbilical cord mesenchymal stem cell exosomes are obtained by: According to (0.5-3.5) × 10 4 The P3-P5 umbilical cord mesenchymal stem cells were inoculated into the culture medium at a density of cells / mL, and the supernatant was obtained. The supernatant was subjected to ultracentrifugation to obtain the precipitate, which was then freeze-dried.

[0014] Furthermore, the culture medium consists of DMEM / F12 basal culture medium and the following components added to the culture medium: 5-10% FBS, 25-40 ng / mL IL-21, and 1-3 ng / mL EGF.

[0015] Furthermore, the culture time is 2-3 days, and the culture conditions are 37° C. and 5% CO 2 .

[0016] The second object of the present invention is achieved by adopting the following technical solution: The method for preparing the medical dressing for promoting diabetic wound healing comprises the following steps: (1) Add hydroxypropyl chitosan and xanthan gum to water according to the mass percentage ratio, stir until completely dissolved, add glycerol, and mix well to obtain a gel matrix; (2) Add oligopeptide-1, jasmine, stem cell exosomes and modified CaSi2 nanosheets into the gel matrix of step (1) according to the mass percentage ratio and mix them evenly.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. Modified CaSi2 nanosheets and other ingredients are added to the medical dressing of the present invention. The test results show that the modified CaSi2 nanosheets obtained by the present invention can promote wound healing. Specifically, the modification process of CaSi2 nanosheets utilizes the chelating properties of phytic acid to dissolve the calcium ions in the CaSi2 nanosheets while retaining the complete silicon-based skeleton, so that the modified CaSi2 nanosheets can enhance the stability and angiogenesis activity of stem cell exosomes, thereby improving the impaired angiogenesis of diabetic wounds and facilitating wound healing.

[0018] 2. The medical dressing of the present invention also contains ingredients such as jasmine and oligopeptide-1. The test results show that the combination of jasmine and oligopeptide-1 can effectively inhibit the excessive proliferation of scar tissue and reduce the formation of scars.

[0019] 3. The preparation method of the medical dressing provided by the present invention has simple steps and simple operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a morphological diagram of P4 umbilical cord mesenchymal stem cells. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with specific embodiments. It should be noted that, under the premise of no conflict, the embodiments described below or the technical features can be arbitrarily combined to form new embodiments. The specific conditions not specified in the embodiments are carried out under normal conditions. The reagents or instruments used are conventional products obtained through commercial channels unless otherwise specified.

[0022] Umbilical cord mesenchymal stem cell exosomes are obtained by: Clean 1mm 3 Umbilical cord tissues of different sizes were spread in a culture dish containing DMEM / F12 medium containing 10% fetal bovine serum. The culture dish was cultured in a cell culture incubator at 37°C and 5% CO2 until the cell confluence reached 85%. After digestion, primary cultured umbilical cord mesenchymal stem cells were obtained. 2×10 4 The primary cultured umbilical cord mesenchymal stem cells were inoculated into a culture medium (composed of DMEM / F12 basal medium and the following components added to the culture medium: 8% FBS, 30ng / mL IL-21, 2ng / mL EGF) at a density of 100 / mL. When the cell confluence reached 90%, the cells were digested with trypsin and then passaged in a cell culture incubator at 37°C and 5% CO2. The passage ratio was 1:3. The cells were passaged 4 times to obtain P4 umbilical cord mesenchymal stem cells. The morphology of P4 umbilical cord mesenchymal stem cells is shown in the figure. Figure 1 shown.

[0023] 2×10 4 P4 umbilical cord mesenchymal stem cells were inoculated into culture medium (consisting of DMEM / F12 basal medium and the following components added to the culture medium: 8% FBS, 30ng / mL IL-21, 2ng / mL EGF) at a density of 100 / mL and cultured in a cell culture incubator at 37°C and 5% CO2 for 3 days. The cell culture supernatant was collected and centrifuged and freeze-dried to obtain umbilical cord mesenchymal stem cell exosomes.

[0024] 1. Embodiment Example 1 The present embodiment provides a medical dressing for promoting the healing of diabetic wounds, which is composed of the following raw materials, measured by mass percentage: 0.001% umbilical cord mesenchymal stem cell exosomes, 0.003% oligopeptide-1, 0.007% jasmine, 0.05% modified CaSi2 nanosheets, 4% hydroxypropyl chitosan, 0.2% xanthan gum, 3% glycerol, and the balance is water.

[0025] The preparation process of the modified CaSi2 nanosheets is as follows: According to the dosage ratio of CaSi2 powder and N-methyl-2-pyrrolidone of 1g:50mL, CaSi2 powder with a particle size of 3-5μm was dispersed in N-methyl-2-pyrrolidone, and probe ultrasonic treatment was carried out for 11h under ice bath conditions (ultrasonic conditions: 900W, 25% duty cycle). Then the mixture was centrifuged at 1000rpm for 5min, and the suspension was further centrifuged at 15000rpm for 20min. The precipitate was collected and washed with ethanol three times, and freeze-dried to obtain CaSi2 nanosheets.

[0026] According to the dosage ratio of CaSi2 nanosheets and phytic acid solution of 1g:190mL, CaSi2 nanosheets were added to 0.45mol / L phytic acid solution and reacted at 40℃ for 1h. After the reaction was completed, the solid product was filtered and dried at room temperature.

[0027] The preparation method of the above-mentioned medical dressing for promoting healing of diabetic wounds is as follows: (1) Add hydroxypropyl chitosan and xanthan gum to water according to the mass percentage ratio, stir until completely dissolved, add glycerol, and mix well to obtain a gel matrix; (2) Add oligopeptide-1, jasmine, umbilical cord mesenchymal stem cell exosomes and modified CaSi2 nanosheets into the gel matrix of step (1) according to the mass percentage ratio and mix evenly.

[0028] Example 2 The present embodiment provides a medical dressing for promoting healing of diabetic wounds, which is composed of the following raw materials, measured by mass percentage: 0.012% umbilical cord mesenchymal stem cell exosomes, 0.005% oligopeptide-1, 0.01% jasmine, 0.07% modified CaSi2 nanosheets, 6% hydroxypropyl chitosan, 0.5% xanthan gum, 5% glycerol, and the balance is water.

[0029] The preparation process of the modified CaSi2 nanosheets is as follows: According to the dosage ratio of CaSi2 powder and N-methyl-2-pyrrolidone of 1g:55mL, CaSi2 powder with a particle size of 3-5μm was dispersed in N-methyl-2-pyrrolidone and subjected to probe ultrasonic treatment for 12h under ice bath conditions (ultrasonic conditions: 900W, 25% duty cycle). The mixture was then centrifuged at 1000rpm for 5min, and the suspension was further centrifuged at 15000rpm for 20min. The precipitate was collected and washed with ethanol three times, and freeze-dried to obtain CaSi2 nanosheets.

[0030] According to the dosage ratio of CaSi2 nanosheets and phytic acid solution of 1g:200mL, CaSi2 nanosheets were added to 0.5mol / L phytic acid solution and reacted at 45℃ for 0.5h. After the reaction was completed, the solid product was filtered and dried at room temperature.

[0031] The preparation method of the above-mentioned medical dressing for promoting healing of diabetic wounds is as follows: (1) Add hydroxypropyl chitosan and xanthan gum to water according to the mass percentage ratio, stir until completely dissolved, add glycerol, and mix well to obtain a gel matrix; (2) Add oligopeptide-1, jasmine, umbilical cord mesenchymal stem cell exosomes and modified CaSi2 nanosheets into the gel matrix of step (1) according to the mass percentage ratio and mix evenly.

[0032] Example 3 The present embodiment provides a medical dressing for promoting the healing of diabetic wounds, which is composed of the following raw materials, measured by mass percentage: 0.008% of umbilical cord mesenchymal stem cell exosomes, 0.002% of oligopeptide-1, 0.004% of jasmine, 0.03% of modified CaSi2 nanosheets, 2% of hydroxypropyl chitosan, 0.1% of xanthan gum, 0.5% of glycerol, and the balance of water.

[0033] The preparation process of the modified CaSi2 nanosheets is as follows: According to the dosage ratio of CaSi2 powder and N-methyl-2-pyrrolidone of 1g:45mL, CaSi2 powder with a particle size of 3-5μm was dispersed in N-methyl-2-pyrrolidone and subjected to probe ultrasonic treatment for 10h under ice bath conditions (ultrasonic conditions: 900W, 25% duty cycle). The mixture was then centrifuged at 1000rpm for 5min, and the suspension was further centrifuged at 15000rpm for 20min. The collected precipitate was washed three times with ethanol and freeze-dried to obtain CaSi2 nanosheets.

[0034] According to the dosage ratio of CaSi2 nanosheets and phytic acid solution of 1g:180mL, CaSi2 nanosheets were added to 0.4mol / L phytic acid solution and reacted at 35℃ for 1.5h. After the reaction was completed, the solid product was filtered and dried at room temperature.

[0035] The preparation method of the above-mentioned medical dressing for promoting healing of diabetic wounds is as follows: (1) Add hydroxypropyl chitosan and xanthan gum to water according to the mass percentage ratio, stir until completely dissolved, add glycerol, and mix well to obtain a gel matrix; (2) Add oligopeptide-1, jasmine, umbilical cord mesenchymal stem cell exosomes and modified CaSi2 nanosheets into the gel matrix of step (1) according to the mass percentage ratio and mix evenly.

[0036] 2. Comparative Example Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the modified CaSi2 nanosheets are replaced by CaSi2 nanosheets, and the rest is the same as Example 1.

[0037] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the modified CaSi2 nanosheets are omitted, and the rest is the same as Example 1.

[0038] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that oligopeptide-1 is omitted, the content of jasmine is increased to 0.01%, and the rest is the same as Example 1.

[0039] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that the jasmine is omitted, the content of oligopeptide-1 is increased to 0.01%, and the rest is the same as Example 1.

[0040] 3. Test examples (1) Test subjects A total of 70 6-week-old male BALB / c mice were acclimated for 2 weeks before administration.

[0041] (2) Construction of diabetes model All mice were fasted for 12 hours and then intraperitoneally injected with 50 mg / kg streptozotocin (STZ) for 5 consecutive days. After the administration, blood was collected from the tail vein every 5 days, and blood glucose levels were measured with a blood glucose meter. After 3 weeks, when the fasting glucose concentration of mice was higher than 300 mg / L, the mice were considered to have diabetes.

[0042] (3) Experimental process All diabetic model mice were randomly divided into Example 1-3 group and Comparative Example 1-4 group, 10 mice in each group. All mice were fixed, and the hair on the back of the mice was removed and disinfected with 75% alcohol. Then 6 mg / mL of sodium pentobarbital solution was intraperitoneally injected to anesthetize the mice, and a circular full skin wound with a diameter of 8 mm was formed on the back of the anesthetized mice. The wounds were treated with the medical dressings obtained in Example 1-3 and Comparative Example 1-4, respectively, and the dressings were changed every 2 days.

[0043] (4) Detection indicators Wound healing: The wound surfaces of the mice in Example 1-3 groups and Comparative Example 1-2 groups were photographed on the 0th, 4th, 8th and 16th days of treatment, and the wound areas were measured and analyzed using ImageJ software. The results are shown in Table 1.

[0044] Scar residual width: After the wound healed, the width of the widest part of the scar residual of the mice in Example 1-3 groups and Comparative Example 3-4 groups was calculated. The results are shown in Table 2.

[0045] Table 1: Residual wound area after using medical dressings of Example 1-3 and Comparative Example 1-2 Table 2: Scar width after using medical dressings of Example 1-3 and Comparative Example 1-2 As can be seen from Table 1, the medical dressings obtained in Examples 1-3 of the present invention can promote wound healing. Compared with Examples 1-3, Comparative Example 1 replaces the modified CaSi2 nanosheets with CaSi2 nanosheets, and Comparative Example 2 omits the modified CaSi2 nanosheets. The two groups of medical dressings have poor effects on wound healing. The above results show that the modified CaSi2 nanosheets obtained in the present invention can promote wound healing. Specifically, the present invention utilizes the chelating properties of phytic acid in the modification process of CaSi2 nanosheets, so that the calcium ions in the CaSi2 nanosheets are dissolved, while retaining the complete silicon-based skeleton, so that the modified CaSi2 nanosheets can enhance the stability and angiogenesis activity of umbilical cord mesenchymal stem cell exosomes, thereby improving the impaired angiogenesis of diabetic wounds and facilitating wound healing.

[0046] As shown in Table 2, the medical dressings obtained in Examples 1-3 of the present invention are beneficial to the repair of scars after wound healing. Compared with Examples 1-3, Comparative Example 3 omits oligopeptide-1 and increases the content of jasmine; Comparative Example 4 omits jasmine and increases the content of oligopeptide-1. The two groups of medical dressings have poor repair effects on scars after wound healing. The above results show that the combination of jasmine and oligopeptide-1 can effectively inhibit the excessive proliferation of scar tissue and reduce the formation of scars.

[0047] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A medical dressing for promoting healing of diabetic wounds, characterized in that: Calculated by mass percentage, it includes the following raw materials: Stem cell exosomes 0.008-0.012%, oligopeptide-1 0.002-0.005%, jasmine 0.004-0.01%, modified CaSi2 nanosheets 0.03-0.07%, hydroxypropyl chitosan 2-6%, xanthan gum 0.1-0.5%, glycerol 0.5-5%, and the balance is water.

2. The medical dressing for promoting diabetic wound healing according to claim 1, characterized in that: The preparation process of the modified CaSi2 nanosheets is as follows: The CaSi2 nanosheets are added into the phytic acid solution for reaction, and purified after the reaction is completed to obtain the product.

3. The medical dressing for promoting diabetic wound healing according to claim 2, characterized in that: The dosage ratio of the CaSi2 nanosheets to the phytic acid solution is 1 g: (180-200) mL, and the concentration of the phytic acid solution is 0.4-0.5 mol / L.

4. The medical dressing for promoting diabetic wound healing according to claim 2, characterized in that: The reaction temperature is 35-45°C, and the reaction time is 0.5-1.5h.

5. The medical dressing for promoting diabetic wound healing according to claim 2, characterized in that: The preparation process of the CaSi2 nanosheets is as follows: dispersing CaSi2 powder into N-methyl-2-pyrrolidone, performing probe ultrasonic treatment and centrifugation under ice bath conditions, collecting the precipitate and washing and drying the precipitate.

6. The medical dressing for promoting diabetic wound healing according to claim 5, characterized in that: The dosage ratio of the CaSi2 powder and N-methyl-2-pyrrolidone is 1 g: (45-55) mL, and the time of the probe ultrasonic treatment is 10-12 h.

7. The medical dressing for promoting diabetic wound healing according to claim 1, characterized in that: The stem cell exosomes are umbilical cord mesenchymal stem cell exosomes.

8. The medical dressing for promoting healing of diabetic wounds according to claim 7, characterized in that: The method for obtaining the umbilical cord mesenchymal stem cell exosomes is: According to (0.5-3.5) × 10 4 The P3-P5 umbilical cord mesenchymal stem cells were inoculated into the culture medium at a density of cells / mL, and the supernatant was obtained. The supernatant was subjected to ultracentrifugation to obtain the precipitate, which was then freeze-dried.

9. The medical dressing for promoting diabetic wound healing according to claim 8, characterized in that: The culture medium consists of DMEM / F12 basal medium and the following components added to the culture medium: 5-10% FBS, 25-40 ng / mL IL-21, and 1-3 ng / mL EGF.

10. The method for preparing the medical dressing for promoting diabetic wound healing according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) Add hydroxypropyl chitosan and xanthan gum to water according to the mass percentage ratio, stir until completely dissolved, add glycerol, and mix well to obtain a gel matrix; (2) Add oligopeptide-1, jasmine, stem cell exosomes and modified CaSi2 nanosheets into the gel matrix of step (1) according to the mass percentage ratio and mix them evenly.

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