CN-121971697-A - Composite functional microsphere for repairing radiation injury and promoting collagen regeneration as well as preparation method and application thereof

CN121971697ACN 121971697 ACN121971697 ACN 121971697ACN-121971697-A

Abstract

The invention discloses a composite functional microsphere for repairing radiation injury and promoting collagen regeneration, a preparation method and application thereof, wherein the microsphere comprises a porous microsphere carrier prepared from a polymer material with excellent biocompatibility and degradability, and a repairing polypeptide with cell penetration, free radical removal, DNA protection and anti-apoptosis functions is covalently bonded on the internal load or surface of the porous microsphere carrier. The porous microsphere carrier can be used as a slow-release reservoir and a physical support bracket which reside for a long time, can realize continuous and controllable release of polypeptide through pores or surface modification layers in the microsphere, and can provide free radical removal and cell protection effects for damaged parts, meanwhile, the stable three-dimensional space structure of the porous microsphere carrier can provide anchor points for repairing cells such as fibroblasts and the like, and can directly guide and support ordered deposition of new-born collagen fibers, so that long-acting molecular protection is realized, and meanwhile, substantial regeneration and reconstruction of tissue structures are promoted mechanically.

Inventors

CHEN SILEI
JIANG YUJIAO
YAN YAN
WU SHUWANG
CHENG XIAJU
MA WENJIE
LIU YIFAN

Assignees

苏州大学

Dates

Publication Date: 20260505
Application Date: 20260119

Claims (10)

1. The composite functional microsphere for repairing radiation injury and promoting collagen regeneration is characterized by comprising a porous microsphere carrier prepared by adopting a polymer material with excellent biocompatibility and degradability, wherein the inner load or the surface of the porous microsphere carrier is covalently combined with a repair polypeptide with cell penetration, free radical removal, DNA protection and anti-apoptosis functions; The high polymer material is a lactide-glycolide copolymer, the LA/GA molar ratio is 50:50, and the molecular weight is 10000-30000Da; The repair polypeptide is a composite polypeptide, the amino acid sequence of the repair polypeptide is Arg-Gly-Asp-Ser-Lys-Tyr-Glu, and the molecular weight of the repair polypeptide is 800Da.
2. A method for preparing composite functional microspheres for repairing radiation injury and promoting collagen regeneration, which is characterized by comprising the following steps of: Step 1) selecting a lactide-glycolide copolymer with excellent biocompatibility and degradability as a high molecular carrier material, wherein the LA/GA molar ratio of the lactide-glycolide copolymer is 50:50, and the molecular weight is 10000-30000Da; Selecting a compound polypeptide with cell penetration, free radical removal, DNA protection and anti-apoptosis functions as a repair polypeptide, wherein the amino acid sequence of the compound polypeptide is Arg-Gly-Asp-Ser-Lys-Tyr-Glu, and the molecular weight of the compound polypeptide is 800Da; selecting dichloromethane as an organic phase solvent; Polyvinyl alcohol is selected as a water phase emulsifier; Phosphate buffer solution with pH value of 7.4 is selected as a system buffer solution; step 2) dissolving a certain mass of lactide-glycolide copolymer in a certain volume of dichloromethane, magnetically stirring until the lactide-glycolide copolymer is completely dissolved, then adding a certain mass of composite polypeptide, and continuously stirring for a period of time to form uniform oil phase suspension; Step 3) preparing a certain volume of 2% (w/v) polyvinyl alcohol aqueous solution by using polyvinyl alcohol to form a water phase containing an emulsifier, and preheating to a certain temperature for standby; Step 4) slowly injecting the uniform oil phase suspension into the water phase containing the emulsifier, and carrying out high-speed shearing and emulsification for a period of time to obtain W/O type colostrum; step 5) preparing a certain volume of 0.5% (w/v) polyvinyl alcohol aqueous solution by using polyvinyl alcohol, transferring the colostrum into the aqueous solution, and emulsifying for a period of time at room temperature under magnetic stirring to realize slow volatilization of the solvent; Step 6) centrifuging the emulsion obtained after the room temperature emulsification, collecting the precipitate, washing the precipitate for a plurality of times by using the phosphate buffer solution, and removing the residual polyvinyl alcohol and the unsupported composite polypeptide; and 7) placing the purified precipitate in a vacuum freeze dryer for treatment for a period of time to obtain white loose microsphere powder, wherein each microsphere in the microsphere powder is provided with a porous microsphere carrier formed by a lactide-glycolide copolymer, and the repairing polypeptide is covalently bound on the internal load or the surface of the porous microsphere, so that the composite functional microsphere for repairing radiation injury and promoting collagen regeneration is obtained.
3. The method according to claim 2, wherein in step 2, the mass ratio of the lactide-glycolide copolymer (PLGA) to the composite polypeptide is 5:1, and the stirring is continued for 30min.
4. The method according to claim 2, wherein in step 3, the preheating temperature is 37 ℃.
5. The method according to claim 2, wherein in step 4, the volume ratio of the dichloromethane to the 2% (w/v) aqueous polyvinyl alcohol solution is 1:10, and the rotation speed of high-speed shearing emulsification is 20000rpm for 10min.
6. The method according to claim 2, wherein in step 5, the volume ratio of the colostrum to the 0.5% (w/v) aqueous solution of polyvinyl alcohol is 11:20, and the rotation speed of the magnetic stirring is 500rpm for 2 hours.
7. The method according to claim 2, wherein in step 6, the washing is performed 3 times, the rotational speed of the centrifugation is 8000 rpm, and the time is 15 minutes.
8. The method according to claim 2, wherein in step 7, the vacuum freeze-drying is performed at-50 ℃ for 24 hours.
9. Use of the composite functional microsphere for repairing radiation damage and promoting collagen regeneration according to claim 1 and/or the composite functional microsphere for repairing radiation damage and promoting collagen regeneration prepared by the preparation method according to any one of claims 2 to 8 for preparing a minimally invasive implantable medical device having both functions of repairing radiation tissue damage and promoting collagen regeneration.
10. The use of claim 9, wherein the radiation tissue injury comprises radiodermatitis and tissue fibrosis.

Description

Composite functional microsphere for repairing radiation injury and promoting collagen regeneration as well as preparation method and application thereof Technical Field The invention belongs to the technical field of biomedical materials and regenerative medicine, and particularly relates to a composite functional microsphere for repairing radiation injury and promoting collagen regeneration, and a preparation method and application thereof. Background Radiation therapy is one of the main treatment means of malignant tumors, but can cause unavoidable radiation damage to surrounding normal tissues while killing tumor cells, such as radiodermatitis, pneumonia, enteritis, subsequent fibrosis and the like. These lesions can severely affect the quality of life of the patient and even limit the dose of radiation therapy, affecting the tumor control effect. Currently, clinical interventions for radiotissue damage are very limited. Traditional treatments have focused on symptom management, such as using glucocorticoid ointments to inhibit inflammation, or using silver ion dressings to prevent infection, or using moisturizers to relieve dryness. These methods only provide superficial, passive relief and cannot fundamentally interfere with the core pathological processes of radiation injury, namely cellular DNA damage triggered by the large number of Reactive Oxygen Species (ROS) directly and indirectly generated by radiation, lipid peroxidation, mitochondrial dysfunction and consequent apoptosis and necrosis. In recent years, some studies have attempted to promote damage repair using antioxidants (such as amifostine), growth factors, or stem cell therapies. However, these strategies often face challenges such as short half-life of small molecule drugs, lack of targeting, need for repeated dosing, susceptibility of protein drugs to deactivation in complex damaging microenvironments, and safety, cost and ethical concerns with cell therapies. More importantly, most of the existing methods focus on "protection" or "stimulation" at the cell level, neglect structural damage and functional loss caused by degradation and abnormal remodeling of extracellular matrix (especially collagen) after radiation injury, and are difficult to realize in a true sense "tissue regeneration". Therefore, the development of an integrated treatment strategy which can realize targeted delivery, long-acting effect and simultaneously realize 'cell protection' and 'matrix reconstruction' is an urgent need for solving the problem of repairing the radioactive injury, and has great clinical significance and market value. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a composite functional microsphere for repairing radiation injury and promoting collagen regeneration, and a preparation method and application thereof, and aims to synchronously solve the problems of molecular damage and structural defect in radiation injury through an integrated microsphere system, and is expected to be applied to the fields of tissue injury repair and regeneration medicine. In order to solve the technical problems and achieve the technical effects, the invention is realized by the following technical scheme: The composite functional microsphere for repairing radiation injury and promoting collagen regeneration comprises a porous microsphere carrier prepared from a high polymer material with excellent biocompatibility and degradability, wherein the inner load or surface of the porous microsphere carrier is covalently bonded with a repair polypeptide with cell penetration, free radical removal, DNA protection and anti-apoptosis functions; the high polymer material is lactide-glycolide copolymer (PLGA), the LA/GA molar ratio is 50:50, and the molecular weight is 10000-30000Da; The repair polypeptide is a composite polypeptide, the amino acid sequence of which is Arg-Gly-Asp-Ser-Lys-Tyr-Glu, and the molecular weight of which is about 800Da. The preparation method of the composite functional microsphere for repairing radiation injury and promoting collagen regeneration is based on an emulsification-solvent volatilization method and comprises the following steps of: Step 1) selecting a lactide-glycolide copolymer (PLGA) with excellent biocompatibility and degradability as a high molecular carrier material, wherein the LA/GA molar ratio of the lactide-glycolide copolymer is 50:50, and the molecular weight is 10000-30000Da; Selecting a compound polypeptide with cell penetration, free radical removal, DNA protection and anti-apoptosis functions as a repair polypeptide, wherein the amino acid sequence of the compound polypeptide is Arg-Gly-Asp-Ser-Lys-Tyr-Glu, and the molecular weight is about 800Da; selecting dichloromethane as an organic phase solvent; Polyvinyl alcohol (PVA) is selected as a water phase emulsifier; Phosphate Buffer (PBS) with pH value of 7.4 is selected as a system buffer; step 2) dissolving a certain mass of lactide-