Wound repair system based on cooperation of metformin hydrogel and ultrasound and application of wound repair system in promotion of wound repair

Abstract

The invention discloses a wound repair system based on metformin hydrogel and ultrasound cooperation and application of the wound repair system in promoting wound repair. The system comprises an ultrasonic stimulation unit, a gel release unit, a core control unit and a wound monitoring unit. The ultrasonic stimulation unit acts on the wound at the frequency of 20 kHz to 3 MHz and the strength of 0.1 W / cm to 3 W / cm; and the gel release unit is used for conveying hydrogel containing 0.5 to 3 weight percent of metformin and 1 to 10 weight percent of oxidized dextran. The core control unit regulates and controls ultrasonic parameters and gel release according to feedback of the monitoring unit, and the ultrasonic parameters and the gel release can work synchronously or successively. According to the system, macrophage polarization and hydrogel continuous drug release are regulated and controlled through ultrasound, inflammation is improved, revascularization is promoted, and an effective treatment strategy is provided for chronic wound surfaces difficult to heal.

Description

Technical Field

[0001] This invention belongs to the field of regenerative medicine and biomedical engineering technology, specifically relating to a wound repair system based on metformin hydrogel and ultrasound synergy and its application in promoting wound repair. Background Technology

[0002] Chronic wounds, especially diabetic foot ulcers, have become a major challenge in modern medicine due to their slow healing process and high susceptibility to infection and recurrence. Current treatments mainly include drug therapy, surgery, and physical therapy, but these methods have many drawbacks, such as slow efficacy, poor patient compliance, high treatment costs, and potential risks of complications. Diabetic patients often have vascular complications and immune dysfunction, which further complicate wound healing.

[0003] Wound repair is a complex process involving multiple biological stages, including inflammatory response, cell proliferation, matrix deposition, and tissue remodeling. Macrophages, as key immune cells, play a crucial role in this process, significantly impacting both the inflammatory response and tissue repair. M2 macrophages, in particular, are especially important in promoting wound healing due to their anti-inflammatory properties. However, existing treatments often struggle to effectively regulate macrophage polarization, resulting in an ineffective improvement of the inflammatory environment and thus delaying the wound healing process.

[0004] Furthermore, angiogenesis is a crucial step in wound healing, but existing treatments have limited effectiveness in promoting it. Metformin, a widely used drug for treating type 2 diabetes, has also shown potential in recent years to promote angiogenesis and tissue repair. However, how to directly apply the active ingredient of metformin to the wound site and how to combine it with other treatments to maximize its efficacy remain challenges in current research. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] In view of the problems existing in the above and / or prior art, the present invention is proposed.

[0007] This invention proposes a wound repair system based on the synergistic use of metformin hydrogel and ultrasound. This system combines ultrasound-mediated macrophage modulation technology with the application of metformin hydrogel. Through non-invasive ultrasound stimulation, this invention effectively modulates macrophage polarization, promoting their conversion to the M2 type, thereby improving the inflammatory environment. Simultaneously, the local application of metformin hydrogel provides continuous drug release to the wound site, promoting angiogenesis and tissue repair. This system, combining ultrasound and drug delivery, offers a new, more effective, and safer strategy for treating chronic, difficult-to-heal wounds.

[0008] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide a wound repair system based on metformin hydrogel and ultrasound synergy.

[0009] To solve the above-mentioned technical problems, the present invention provides the following technical solution: including, Ultrasonic stimulation unit 100 is used to deliver ultrasound waves at a frequency of 20kHz-3MHz and a pulse intensity of 0.1W / cm². 2 -3W / cm 2 The intensity is delivered to the area of ​​the wound to be repaired; The gel release unit 200 is used to deliver metformin hydrogel to the surface of the wound area to be repaired.

[0010] As a preferred embodiment of the wound repair system based on metformin hydrogel and ultrasound synergy described in this invention, the wound repair system further includes: The core control unit 300 is used to control the ultrasound parameters in the ultrasound stimulation unit 100 and the gel release in the gel release unit 200. The wound monitoring unit 400 is used to monitor the wound environment and the healing progress.

[0011] As a preferred embodiment of the wound repair system based on metformin hydrogel and ultrasound synergy described in this invention, the ultrasound stimulation unit 100 is provided with an adjustable flexible support 101 to support the ultrasound probe 102.

[0012] As a preferred embodiment of the wound repair system based on metformin hydrogel and ultrasound synergy described in this invention, the gel release unit 200 is provided with a gel storage chamber 201, and a guide channel or adjustable nozzle is provided at the gel outlet of the gel storage chamber 201 to control the coverage of the wound area after the metformin hydrogel is released.

[0013] As a preferred embodiment of the wound repair system based on metformin hydrogel and ultrasound synergy described in this invention, the wound monitoring unit 400 includes one or more of an integrated temperature sensor, humidity sensor, miniature camera, or optical sensor.

[0014] As a preferred embodiment of the wound repair system based on metformin hydrogel and ultrasound synergy described in this invention, the metformin hydrogel contains metformin and oxidized glucan, wherein the mass concentration of metformin in the metformin hydrogel is 0.5wt%-3wt%, and the mass concentration of oxidized glucose is 1wt%-10wt%.

[0015] As a preferred embodiment of the wound repair system based on metformin hydrogel and ultrasound synergy described in this invention, the ultrasound stimulation unit 100 and the gel release unit 200 work synchronously or sequentially.

[0016] As a preferred embodiment of the wound repair system based on metformin hydrogel and ultrasound synergy described in this invention, the ultrasound stimulation unit 200 operates for 1-10 minutes each time.

[0017] As a preferred embodiment of the wound repair system based on metformin hydrogel and ultrasound synergy described in this invention, the core control unit 300 adjusts the operation of the ultrasound stimulation unit 100 and the gel release unit 200 according to the wound environment and repair progress fed back by the wound monitoring unit 400.

[0018] Another object of the present invention is to provide an application of a wound repair system based on metformin hydrogel and ultrasound synergy in promoting wound healing.

[0019] Beneficial effects of this invention: This invention's system effectively improves the inflammatory environment of wounds. Through ultrasound stimulation, it regulates macrophage polarization, promoting their conversion to the anti-inflammatory M2 type, reducing levels of inflammatory factors such as TNF-α and IL-6, and increasing IL-10 levels, thus alleviating wound inflammation. Simultaneously, the local release of metformin hydrogel, combined with ultrasound, significantly increases VEGF levels, enhances the number and maturity of new blood vessels, and provides nutritional support for wound repair. This system accelerates granulation tissue formation and re-epithelialization, increases collagen deposition, and optimizes fiber arrangement. In diabetic mice, the wound healing rate after 14 days reached over 95%, approaching normal levels. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 The figure shows the characterization results of the metformin hydrogel prepared in Example 1 of this invention.

[0021] Figure 2 This is an overall structural diagram of the wound repair system based on metformin hydrogel and ultrasound synergy, as described in Embodiment 2 of the present invention.

[0022] Figure 3 This is a schematic diagram illustrating the application scenario of the wound repair system based on metformin hydrogel and ultrasound synergy in the repair of full-thickness wounds in diabetic mice, as described in Embodiment 3 of the present invention.

[0023] Figure 4 The wound sizes of the treatment groups of Example 3, Comparative Example 1, and Comparative Example 2 on days 3, 5, 7, 10, and 14 are shown.

[0024] Figure 5 The results of CD206 and CD80 staining of mouse wound tissues in Example 3, Comparative Example 1, and Comparative Example 2 on day 4 are shown.

[0025] Figure 6 The results of ELISA detection of TNF-α, IL-6, IL-10 and VEGF levels in the wound tissues of mice in Example 3, Comparative Example 1 and Comparative Example 2 on day 4 are shown.

[0026] Figure 7 The results of CD31 and α-SMA staining in the wound tissues of mice in Example 3, Comparative Example 1, and Comparative Example 2 on day 4 are shown.

[0027] Figure 8 The images show the H&E staining results of mouse wound tissues on days 7 and 14 of the treatment groups of Example 3, Comparative Example 1, and Comparative Example 2 of this invention. Detailed Implementation

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0029] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0030] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0031] Unless otherwise specified, the experimental methods used in this invention are conventional methods, and the materials, reagents, methods and instruments used are conventional materials, reagents, methods and instruments in the field, which can be obtained by those skilled in the art through commercial channels.

[0032] The experimental animals used in this invention were 6-8 week old male C57BL / 6 mice (weighing 18-20g), purchased from Shanghai Jiesijie Laboratory Animal Co., Ltd.

[0033] Example 1 Preparation and characterization of metformin hydrogel: 2.5g of dextran was dissolved in 50mL of water, and 2.5g of sodium periodate powder was added. The mixture was stirred at 500r / min at room temperature and reacted for 12h. Then, 3mL of ethylene glycol was added and the reaction was continued for 2h. The resulting liquid was added to a dialysis bag and dialyzed in pure water for 48h. The dialysate was then freeze-dried in a freeze dryer for 24h to obtain oxidized dextran (ODE) in the form of flakes. Weigh 1000 mg of ODE and add it to 9000 mg of deionized water. Heat and stir to dissolve quickly to obtain a 10 wt% oxidized dextran solution. Weigh 300 mg of metformin (Met) and add it to the prepared 10 wt% oxidized dextran solution. Stir the mixed solution in a 50°C water bath at 500 r / min for 1-2 h, and then perform ultrasonic dispersion (power 200 W, time 30 min) to prepare a 10 wt% oxidized dextran 3 wt% metformin hydrogel.

[0034] The 10wt% oxidized dextran and 3wt% metformin hydrogel obtained in this example was freeze-dried and then reconstituted to prepare "10wt% oxidized dextran and 3wt% metformin hydrogels" with mass concentrations of 5wt%, 10wt%, and 15wt%, respectively, and were characterized as follows: Scanning electron microscopy (SEM): A 100 mg hydrogel sample was dried, gold-plated, and fixed on the sample stage. High-resolution imaging of the surface morphology was performed using a scanning electron microscope. Results are as follows: Figure 1 As shown in Figure A, the hydrogel exhibits a uniform and dense porous network structure with regular pores and good connectivity.

[0035] X-ray diffraction (XRD): 100 mg of hydrogel sample was prepared into powder with a particle size <200 mesh, placed on an XRD sample stage, and diffraction patterns were collected after setting scanning parameters to analyze the crystal structure. Results are as follows: Figure 1 As shown in Figure B, the hydrogel exhibits an amorphous structure, and the crystallization peaks of Met have largely disappeared, indicating that Met has been successfully loaded and is bound in an amorphous state within the hydrogel framework.

[0036] Fourier Transform Infrared Spectroscopy (FTIR): A 100 mg hydrogel sample was compressed into a KBr pellet, and spectral data were collected using a Fourier Transform Infrared spectrometer to identify chemical bonds and functional groups in the sample. Results are as follows: Figure 1 As shown in Figure C, the hydrogel exhibits a typical C=N stretching vibration peak, and the position of the hydroxyl peak is red-shifted, indicating the presence of Schiff base bonds and hydrogen bonds, thus verifying the chemical crosslinking between Met and ODE.

[0037] 1H NMR: 100 mg of hydrogel sample was dissolved in DMSO, placed in an NMR tube, and the scanning parameters were set to collect the 1H NMR signal to analyze the chemical environment of the sample. Results are as follows: Figure 1 As shown in Figure D, the hydrogel exhibits a new proton peak at δ 5.0-5.8 ppm while retaining the characteristic peak of Met (δ≈2.9 ppm), further demonstrating the successful formation of the ODE-Met hydrogel.

[0038] Example 2 This embodiment constructs a wound repair system based on the synergistic effect of metformin hydrogel and ultrasound, referring to... Figure 2 The overall layout of the system is as follows: The ultrasonic stimulation unit 100 and the gel release unit 200 act simultaneously on the wound surface W; The ultrasonic stimulation unit 100 is equipped with an ultrasonic probe 102 supported by a flexible and liftable structure 101. The probe is used to emit ultrasonic waves, and the ultrasonic wave action area is the upper surface of the wound. The gel release unit 200 includes a cylindrical container-shaped gel storage chamber 201, which represents the place where metformin hydrogel is stored. A nozzle is provided at the outlet of the gel storage chamber 201 to control the release and coverage of the gel, and its area of ​​action is the upper surface of the wound. The core control unit 300 is connected to the ultrasound stimulation unit 100 and the gel release unit 200, and is used to control the ultrasound parameters in the ultrasound stimulation unit 100 and the gel release in the gel release unit 200. The wound monitoring unit 400 is equipped with a temperature sensor, a humidity sensor, a miniature camera or an optical sensor, located on the upper surface of the wound, to monitor the wound environment and repair status and provide feedback to the core control unit 300.

[0039] In this embodiment, the various units can be connected and integrated using conventional methods.

[0040] Example 3 Reference Figure 3 This embodiment verifies the application of a wound repair system based on metformin hydrogel and ultrasound synergy in promoting wound healing. Specifically: Healthy C57BL / 6 mice aged 6-8 weeks were selected and fed a high-fat, high-sugar diet for 7 days after entering the animal housing. After 7 days of feeding, the mice were fasted and deprived of water for 12 hours. The model group mice were intraperitoneally injected with streptozotocin chain (STZ) at a dose of 150 mg / kg. Seven days after the injection, random blood glucose was measured by tail blood collection and Yuwell blood glucose meter. A blood glucose value greater than 16.67 mmol / L was the standard for diabetes in mice, and the diabetic model group (DW) was constructed. After successful modeling, a 1 cm diameter wound was cut on the back of the mouse, designated as day 0. A wound repair system based on metformin hydrogel and ultrasound was applied, and the wound site was stimulated with ultrasound (frequency 1 MHz, intensity 1 W / cm²) once on days 1, 2, and 3. 2 The treatment group (with a duty cycle of 20% and an action time of 5 min) and 100 μL of metformin hydrogel were designated as the ultrasound combined with metformin hydrogel group (US@Gel).

[0041] Comparative Example 1 The difference between this comparative example and Example 2 is that after successful modeling, a 1 cm diameter wound was cut off on the back of the mouse as day 0. On days 1, 2 and 3, 100 μL of metformin hydrogel was applied to the surface of the wound. This treatment group is referred to as the metformin hydrogel group (Gel).

[0042] Comparative Example 2 The difference between this comparative example and Example 2 is that, after successful modeling, a 1cm diameter wound was cut on the back of the mouse, designated as day 0. On days 1, 2, and 3, the mouse was given ultrasound stimulation (frequency 1MHz, intensity 1W / cm²) at the wound site. 2 The treatment group (with a duty cycle of 20% and an action time of 5 minutes) is referred to as the ultrasound group (US).

[0043] Simultaneously, using a normal group as a control, wound size was observed and recorded on days 3, 5, 7, 10, and 14 in the normal group (Control), model group (DW), metformin hydrogel group (Gel), ultrasound group (US), and ultrasound combined with metformin hydrogel group (US@Gel). Results are as follows: Figure 4 As shown, the US@Gel group mice had the fastest wound closure speed, with a healing rate of over 95% after 14 days, which is close to that of the normal control group.

[0044] On day 4, tissue samples were collected from the wound sites of mice in each group for CD206 and CD80 staining analysis to determine the number and type of macrophages. Results are as follows: Figure 5 As shown, compared with the DW group, the US@Gel group showed a significant increase in M2 macrophages and a significant decrease in M1 macrophages, indicating that ultrasound combined with hydrogel can promote the transformation of the wound site from pro-inflammatory to anti-inflammatory.

[0045] On day 4, tissue samples were collected from the wound sites of mice in each group. The samples were ground and cytokines were extracted using PBS buffer. The levels of TNF-α, IL-6, IL-10, and VEGF were analyzed using an ELISA kit. Results are as follows: Figure 6 As shown, the levels of inflammatory factors TNF-α and IL-6 decreased in the US@Gel group, while the levels of IL-10 and VEGF increased, indicating that ultrasound combined with hydrogel can inhibit the inflammatory environment at the wound site.

[0046] Tissue samples were collected from the wound sites of mice in each group on days 7 and 14 for CD31 and α-SMA staining analysis to determine the number of new blood vessels in the wound sites. Results are as follows: Figure 7 As shown, the US@Gel group had the highest number and maturity of new blood vessels, indicating that ultrasound combined with hydrogel can promote angiogenesis at the wound site.

[0047] Tissue samples were collected from the wound sites of mice in each group on days 7 and 14 for H&E staining and Masson staining to analyze the pathological condition of the wound sites. Results are as follows: Figure 8 As shown, the US@Gel group exhibited thicker granulation tissue and significantly shortened wound edges on days 7 and 14, suggesting that it accelerated the re-epithelialization process. Simultaneously, the US@Gel group showed increased collagen deposition and a more dense and orderly fiber arrangement. These data indicate that ultrasound combined with hydrogel therapy significantly improves the inflammatory microenvironment, promotes angiogenesis and collagen deposition, and accelerates the healing of diabetic wounds.

[0048] In summary, this invention discloses a wound repair system based on the synergistic effect of metformin hydrogel and ultrasound, and its application in promoting wound healing. The system comprises an ultrasound stimulation unit, a gel release unit, a core control unit, and a wound monitoring unit. The ultrasound stimulation unit acts on the wound at a frequency of 20kHz-3MHz and an intensity of 0.1-3W / cm². The gel release unit delivers a hydrogel containing 0.5-3wt% metformin and 1-10wt% oxidized dextran. The core control unit adjusts the ultrasound parameters and gel release based on feedback from the monitoring unit; both can operate synchronously or sequentially. This system improves inflammation and promotes angiogenesis by using ultrasound to regulate macrophage polarization and continuously releasing drugs from the hydrogel, providing an effective treatment strategy for chronic, difficult-to-heal wounds.

[0049] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A metformin hydrogel based wound repair system in synergy with ultrasound, characterized by: The wound repair system comprises, An ultrasonic stimulation unit (100) for delivering ultrasonic waves at a frequency of 20 kHz - 3 MHz and an intensity of 0.1 W / cm 2 - 3 W / cm 2 to the area of the wound to be repaired; a gel releasing unit (200) for delivering metformin hydrogel to the surface of the wound area to be repaired.

2. The metformin hydrogel based synergistic wound repair system with ultrasound as claimed in claim 1, wherein: The wound repair system further comprises, a core control unit (300) for controlling the ultrasonic parameters in the ultrasonic stimulation unit (100) and the gel releasing in the gel releasing unit (200); a wound monitoring unit (400) for monitoring the wound environment and the repair progress.

3. The metformin hydrogel based synergistic wound repair system with ultrasound of claim 1, wherein: The ultrasonic stimulation unit (100) is provided with a flexible support (101) with adjustable function to support the ultrasonic probe (102).

4. The metformin hydrogel based synergistic wound repair system with ultrasound as claimed in claim 3, wherein: The gel releasing unit (200) is provided with a gel storage bin (201), and a flow guide groove or an adjustable nozzle is arranged at the gel outlet of the gel storage bin (201) for controlling the metformin hydrogel to cover the wound area after being released.

5. The metformin hydrogel based synergistic wound repair system with ultrasound as claimed in claim 2, wherein: The wound monitoring unit (400) comprises one or more of an integrated temperature sensor, a humidity sensor, a miniature camera or an optical sensor.

6. The metformin hydrogel based synergistic wound repair system with ultrasound of claim 1, wherein: The metformin hydrogel comprises metformin and oxidized dextran, wherein the mass concentration of metformin in the metformin hydrogel is 0.5wt%-3wt%, and the mass concentration of oxidized dextran is 1wt%-10wt%.

7. The metformin hydrogel based synergistic wound repair system with ultrasound as claimed in claim 2, wherein: The ultrasonic stimulation unit (100) and the gel releasing unit (200) work synchronously or successively.

8. The metformin hydrogel based synergistic wound repair system with ultrasound as claimed in claim 4 wherein: The working time of the ultrasonic stimulation unit (200) is 1min-10min each time.

9. The metformin hydrogel based synergistic wound repair system with ultrasound as claimed in claim 4 wherein: The core control unit (300) adjusts the working conditions of the ultrasonic stimulation unit (100) and the gel releasing unit (200) according to the wound environment and the repair progress fed back by the wound monitoring unit (400).

10. The application of the wound repair system based on the cooperation of metformin hydrogel and ultrasonic in promoting wound repair according to any one of claims 1-9.

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