Cerium dioxide nanocomposite with mitochondrial targeting activity and ophthalmic medicine
By delivering ceria nanocomplexes with mitochondrial targeting activity in the posterior segment of the eye, the problem of difficulty in delivery of antioxidants in fundus diseases is solved, and effective treatment and delay of fundus oxidative stress damage is achieved.
Patent Information
- Application Number
- CN202510111202.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-23
- Publication Date
- 2025-05-02
AI Technical Summary
The prior art is difficult to effectively deliver antioxidants to the fundus, making it difficult to treat oxidative stress damage to posterior occlusion diseases.
Nanoceria prepared by hydrothermal reaction and triphenylphosphine is modified on its surface to form a ceria nanocomplex with mitochondrial targeting activity, which can eliminate ROS in the mitochondria and protect retinal photoreceptor cells and neuronal cells.
This method can effectively eliminate reactive oxygen free radicals in the mitochondria, reduce cell apoptosis and degeneration, and delay the progress of diseases related to fundus oxidative stress damage.
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Abstract
Description
Technical Field
[0001] The invention relates to the field of medical treatment methods for posterior segment diseases of the eye, in particular to a cerium dioxide nanocomposite and a preparation method thereof. Background Art
[0002] Posterior segment diseases are the leading cause of severe vision loss or even loss in patients worldwide. Common routes of drug administration in ophthalmology include systemic administration, ocular surface administration, periocular administration, and intravitreal injection. Drugs need to overcome multiple anatomical and physiological barriers to exert their effects through these routes, including the cornea, conjunctiva, sclera, and blood-ocular barrier, which significantly reduces the efficiency of fundus delivery of general drugs, making it difficult for therapeutic drugs to enter the fundus, seriously affecting the treatment of fundus diseases.
[0003] The posterior segment of the eye is mainly composed of the vitreous body and the fundus. The fundus is the main tissue for photoreception of the eye. It is composed of the neurosensory layer, the pigment epithelium, and the choroid layer. The retinal photoreceptors are located in the outer layer of the neurosensory layer. They are the key part of converting light into neural signals and are essential for maintaining normal visual function. The main pathologies of posterior segment diseases include ischemia and hypoxia, pathological neovascularization, neuronal degeneration and apoptosis, inflammation and infection, and separation of the neuroepithelium from the pigment epithelium and choroid. Common diseases include age-related macular degeneration, diabetic retinopathy, retinal detachment, retinopathy of prematurity, retinitis pigmentosa, macular edema, optic atrophy, posterior uveitis, endophthalmitis, eye injuries, and ocular manifestations of systemic diseases (such as viral infections, arthritis, and rosacea). Most of these diseases have a certain degree of oxidative stress damage in the early stages. At this time, effective antioxidant methods may be beneficial to the treatment of patients' diseases and delay their progression. As a byproduct of the respiratory chain, ROS is mainly produced in the mitochondria of cells. Excessive ROS generation by mitochondria and mitochondrial membrane permeabilization (MMP) are closely related to the occurrence of apoptosis and autophagy. Mitochondrial dysfunction and MMP are the early stages and key links of many programmed cell death processes. The retina contains abundant mitochondria, especially the photoreceptor cells, where a large number of mitochondria accumulate. These abundant mitochondria provide the necessary energy for visual signal transduction and intracellular material transport. The large accumulation of ROS in mitochondria induces mitochondrial autophagy and apoptosis signaling pathways, which is one of the key links in the occurrence of oxidative stress damage in fundus diseases. However, due to the natural blood-retinal barrier in the eye, systemic administration of antioxidants is difficult to reach the target. There is still no rapid and effective treatment for posterior segment diseases in which photoreceptor cells are damaged due to oxidative stress. Summary of the invention
[0004] In view of the problems existing in the prior art, the present invention provides a cerium dioxide nanocomposite with mitochondrial targeting effect and a preparation method thereof, which can effectively treat and delay diseases related to fundus oxidative stress damage.
[0005] The present invention is achieved through the following technical solutions:
[0006] In a first aspect, the present application provides a cerium dioxide nanocomposite with mitochondrial targeting activity, comprising nano-cerium dioxide and triphenylphosphine modified on the nano-cerium dioxide.
[0007] Preferably, the mass ratio of cerium dioxide to triphenylphosphine is (5-15):(1-4).
[0008] In a second aspect, the present application provides a method for preparing a cerium dioxide nanocomposite having mitochondrial targeting activity, characterized in that it comprises:
[0009] Step 1: Under alkaline conditions, a cerium nitrate solution is subjected to a two-step hydrothermal reaction to obtain nano-cerium dioxide;
[0010] Step 2: modifying nano-cerium dioxide with triphenylphosphine to obtain a cerium dioxide nanocomposite.
[0011] Preferably, the preparation method of the nano cerium dioxide is as follows:
[0012] Adding cerium nitrate solution into alkaline solution to carry out the first hydrothermal reaction, washing and drying to obtain nanorod precursor;
[0013] The nanorod precursor solution is subjected to a second hydrothermal reaction and centrifugally dried to obtain nano-cerium dioxide.
[0014] Preferably, the alkaline solution is sodium hydroxide solution, potassium hydroxide solution, ammonia solution or ethylenediamine solution.
[0015] Preferably, the temperature of the first hydrothermal reaction is 100° C., and the reaction time is 12-36 hours;
[0016] The temperature of the second hydrothermal reaction is 160° C.-220° C., and the reaction time is 12-24 hours.
[0017] Preferably, the method for modifying triphenylphosphine on nano-cerium dioxide is as follows:
[0018] The solution of the triphenylphosphine group donor is mixed evenly with the nano-cerium dioxide, and the mixture is allowed to stand for a certain period of time to modify the triphenylphosphine on the nano-cerium dioxide;
[0019] In the modification of triphenylphosphine on the nano-cerium dioxide, the mass ratio of triphenylphosphine group to nano-cerium dioxide is: (5-15): (1-4).
[0020] Preferably, the solution of the triphenylphosphine group is a triphenylphosphine-polyethylene glycol-carboxyl polymer solution, a triphenylphosphine-polyethylene glycol-chlorin solution, a triphenylphosphine-polydopamine solution, or a triphenylphosphine-polyethylene glycol-folic acid solution.
[0021] Preferably, the process is allowed to stand for 12-16 hours in a light-proof condition to modify triphenylphosphine on the nano-cerium dioxide.
[0022] In a third aspect, the present application provides an ophthalmic drug, comprising the cerium dioxide nanocomplex having mitochondrial targeting activity.
[0023] Compared with the prior art, the present invention has the following beneficial technical effects:
[0024] The present application provides a cerium dioxide nanocomposite with mitochondrial targeting effect. Nanocerium dioxide is prepared by hydrothermal reaction. During the hydrothermal reaction, abundant oxygen defects are brought to the surface of nanocerium dioxide, which will significantly improve the antioxidant properties of nanocerium dioxide. At the same time, triphenylphosphine (TPP) with mitochondrial targeting function is modified on nanocerium dioxide. The modified nanocerium dioxide can be better enriched and located in mitochondria, remove ROS in mitochondria, and continue to accumulate, so as to better protect the mitochondrial membrane potential of hypoxic retinal photoreceptors and other neuronal cells, enhance cell protective autophagy, and reduce cell apoptosis and degeneration.
[0025] Cerium dioxide nanocomplexes are used in eye drops. The cerium dioxide nanocomplexes have excellent mitochondrial targeting function and can be effectively delivered to the mitochondria in the damaged area of the posterior segment of the eye after intraocular injection or ocular surface instillation. They can more effectively catalyze and remove reactive oxygen free radicals in the mitochondria, thereby inhibiting the progression of posterior segment diseases from the source. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope.
[0027] Figure 1 This is a graph showing the survival rate of hypoxia-induced photoreceptor cells by different concentrations of cerium dioxide nanocomposites of the present invention;
[0028] Figure 2 This is a graph showing the effect of the cerium dioxide nanocomposite of the present invention on the ROS level of hypoxia-induced photoreceptor cells;
[0029] Figure 3 This is a diagram showing the effect of the cerium dioxide nanocomposite of the present invention on the mitochondrial membrane potential of photoreceptor cells induced by hypoxia;
[0030] Figure 4 This is a graph showing the effect of the same concentration of the cerium dioxide nanocomposite on the hypoxia-induced photoreceptor cell apoptosis-related proteins;
[0031] Figure 5 The present invention is a diagram showing the distribution of retinal mitochondria and cerium oxide and TPP-cerium oxide materials in various layers of cells of the fundus under a fluorescence confocal microscope 7 days after RD in adult male Sprague-Dawley (SD) rats subjected to subretinal injection of sodium hyaluronate to form experimental retinal detachment (RD), and intravitreal injection of cerium oxide and cerium dioxide nanocomplex 3ul (0.5mg / ml);
[0032] Figure 6 This is a graph showing the changes in TUNEL-positive cells at different times after RD in the present invention. DETAILED DESCRIPTION
[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.
[0034] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0035] A cerium dioxide nanocomposite with mitochondrial targeting activity comprises a nanometer cerium dioxide substrate and triphenylphosphine modified on the nanometer cerium dioxide, wherein the mass ratio of cerium dioxide to triphenylphosphine is (5-15):(1-4).
[0036] The cerium dioxide nanocomposite is modified with TPP on cerium oxide. The modified nano cerium oxide can be better enriched and localized in mitochondria, remove ROS in mitochondria, and continue to accumulate, so as to better protect the mitochondrial membrane potential of hypoxic retinal photoreceptors and other neuronal cells, enhance cell protective autophagy, and reduce cell apoptosis and degeneration.
[0037] A method for preparing a cerium dioxide nanocomposite comprises the following steps:
[0038] Step 1: Under alkaline conditions, a cerium nitrate solution is subjected to a two-step hydrothermal reaction to obtain nano-cerium dioxide;
[0039] Step 2: modifying nano-cerium dioxide with triphenylphosphine to obtain a cerium dioxide nanocomposite.
[0040] As a preferred embodiment of the above-mentioned solution of the present invention, in some embodiments, the preparation method of nano-cerium dioxide is as follows:
[0041] An alkaline solution is prepared, a cerium nitrate solution is added to the alkaline solution for a first hydrothermal reaction, and a nanorod precursor is obtained by washing and drying; the nanorod precursor solution is subjected to a second hydrothermal reaction, and nano-cerium dioxide is obtained after centrifugal drying.
[0042] The first hydrothermal reaction was carried out at 100°C for 12-36h. After cooling to room temperature, the product was washed alternately with ultrapure water and anhydrous ethanol for 5 times, then centrifuged, and finally dried at 60°C for 12h to obtain a bright yellow nanorod precursor.
[0043] The second hydrothermal reaction is carried out at 160-220° C. for 12-24 hours, and finally centrifuged and dried to obtain a light yellow sample, which is nano-cerium dioxide.
[0044] The alkaline solution is sodium hydroxide solution, potassium hydroxide solution, ammonia solution or ethylenediamine solution.
[0045] As a preferred embodiment of the above scheme of the present invention, in some embodiments, under continuous stirring conditions, 10-30 mL of a 0.05-0.3 M alkaline aqueous solution is added dropwise to 100 mL of a 0.1 M cerium nitrate aqueous solution, and stirring is continued for 0.5-3.0 h. The above solution is then transferred to a reactor, reacted at 100° C. for 12-36 h in a high-pressure reactor at a certain pressure (1.2-1.6 atm), cooled to room temperature, washed alternately with ultrapure water and anhydrous ethanol for 5 times, then centrifuged, and finally dried at 60° C. for 12 h to obtain a bright yellow nanorod precursor.
[0046] Subsequently, the precursor nanorods obtained above are dispersed in ultrapure water, ultrasonicated for 3 hours, and then transferred to a hydrothermal kettle and hydrothermaled at 160-220° C. for 12-24 hours. Finally, centrifuged and dried, and the light yellow sample obtained is nano-cerium dioxide.
[0047] As a preferred embodiment of the above scheme of the present invention, in some embodiments, a solution containing triphenylphosphine groups is uniformly mixed with nano-cerium dioxide, and the mixture is allowed to stand for a certain period of time in a light-proof condition to modify triphenylphosphine on the nano-cerium dioxide.
[0048] The solution of the triphenylphosphine group donor is a triphenylphosphine-polyethylene glycol-carboxyl polymer solution, a triphenylphosphine-polyethylene glycol-dihydrochlorin solution, a triphenylphosphine-polydopamine solution, or a triphenylphosphine-polyethylene glycol-folic acid solution.
[0049] Example 1
[0050] A method for preparing a cerium dioxide nanocomposite comprises the following steps:
[0051] Step 1: Prepare nano-cerium dioxide.
[0052] First, weigh 19.2g of sodium hydroxide and dissolve it in 75mL of ultrapure water. Add 5mL of 0.8M cerium nitrate aqueous solution during stirring and continue stirring for 0.5 hours. Then transfer the above solution into a reactor and react at 100°C for 12 hours in a 1.2atm high-pressure reactor. After cooling to room temperature, wash it three times with ultrapure water and ethanol alternately by centrifugation. The product obtained by centrifugation is placed in an oven at 60°C for 12-16 hours to obtain a bright yellow nanorod precursor.
[0053] Then, the nanorod precursor was ultrasonically dispersed in pure water (1 mg / mL), and then transferred to a polytetrafluoroethylene hydrothermal autoclave and reacted at 160°C for 12 hours. After the reactant was cooled to room temperature, it was centrifuged and placed in an oven to dry at 60°C for 12 hours to obtain light yellow nano-cerium dioxide.
[0054] Step 2: modifying the surface of nano-cerium dioxide (CeO2) with triphenylphosphine (TPP) to obtain a cerium dioxide nanocomposite.
[0055] 50 mg of triphenylphosphine-polyethylene glycol-carboxyl polymer (TPP-PEG-COOH) was dissolved in 10 mL of pure water, and 10 mL of CeO2 dispersion (2 mg / mL) was added. After ultrasonic dispersion for 30 min, the mixture was reacted for 12-16 hours under light-proof conditions to obtain a cerium dioxide nanocomposite solution, and the cerium dioxide nanocomposite solution was centrifuged and washed three times with pure water to obtain a cerium dioxide nanocomposite.
[0056] The particle size of the TPP-loaded nano-cerium oxide material prepared in this embodiment is nanometer-level, and the particle size distribution is uniform and concentrated without obvious agglomeration.
[0057] In Example 1, the amount of nano-cerium dioxide added in step 2 is m1, the mass of the cerium dioxide nanocomposite produced in step 2 is m2, and after calculation, the mass of the modified triphenylphosphine group is m2-m1, and the mass ratio of the triphenylphosphine group to the nano-cerium dioxide is (m2-m1):ml.
[0058] Example 2
[0059] A method for preparing a cerium dioxide nanocomposite comprises the following steps:
[0060] Step 1: Prepare nano-cerium dioxide.
[0061] Weigh 19.2g potassium hydroxide and dissolve it in 60mL ultrapure water, then add 20mL of 0.2M cerium nitrate aqueous solution while stirring vigorously. Continue stirring for 1 hour, then transfer the solution into a reactor, react at 100℃ in a 1.5atm autoclave for 24h, cool to room temperature, and wash the reaction product three times with ultrapure water and ethanol alternately by centrifugation. The product obtained by centrifugation is placed in an oven at 60℃ and dried overnight to obtain a bright yellow nanorod precursor.
[0062] Subsequently, the nanorod precursor was ultrasonically dispersed in pure water (1 mg / mL), and then transferred to a polytetrafluoroethylene hydrothermal reactor and treated at 180°C for 16 hours. After the reactant cooled to room temperature, it was centrifuged and placed in an oven at 60°C for overnight drying to obtain light yellow nano-cerium dioxide.
[0063] Step 2: modifying the surface of nano-cerium dioxide (CeO2) with triphenylphosphine (TPP) to obtain a cerium dioxide nanocomposite.
[0064] 50 mg of triphenylphosphine-polyethylene glycol-carboxyl polymer (TPP-PEG-COOH) was dissolved in 5 mL of anhydrous ethanol. Then 10 mL of CeO2 dispersion (2 mg / mL) was added, and after ultrasonic dispersion for 30 min, the mixture was stirred overnight in the dark, and then washed three times by centrifugation with pure water to obtain a cerium dioxide nanocomposite.
[0065] The particle size of the TPP-loaded nano-cerium oxide material prepared in this embodiment is nanometer-level, and the particle size distribution is uniform and concentrated without obvious agglomeration.
[0066] Example 3
[0067] A method for preparing a cerium dioxide nanocomposite comprises the following steps:
[0068] Step 1: Prepare nano-cerium dioxide.
[0069] In 75 mL of ammonia solution (6 M), add 5 mL of 0.8 M cerium nitrate aqueous solution while stirring vigorously, and continue stirring for 3 hours. Then transfer the above solution into a reactor and react at 100 ° C for 36 hours in a high-pressure reactor at 1.2 atm. After cooling to room temperature, the reaction product is washed three times by alternating centrifugation with ultrapure water and ethanol. The product obtained by centrifugation is placed in an oven and dried at 60 ° C overnight to obtain a bright yellow nanorod precursor.
[0070] Then, the nanorod precursor was ultrasonically dispersed in pure water (1 mg / mL), and then transferred to a polytetrafluoroethylene hydrothermal reactor and treated at 220°C for 24 hours. After the reactant cooled to room temperature, it was centrifuged and placed in an oven at 60°C to dry overnight to obtain light yellow nano-cerium dioxide.
[0071] Step 2: The surface of the nano-cerium dioxide (CeO2) obtained in step 1 is modified with triphenylphosphine (TPP) to obtain a cerium dioxide nanocomposite.
[0072] 50 mg of triphenylphosphine-polyethylene glycol-carboxyl polymer (TPP-PEG-COOH) was dissolved in 10 mL of pure water. Then 10 mL of CeO2 dispersion (2 mg / mL) was added. After ultrasonic dispersion for 30 min, the mixture was stirred overnight in the dark to obtain a cerium dioxide nanocomposite solution. The cerium dioxide nanocomposite solution was centrifuged and washed three times with pure water to obtain a cerium dioxide nanocomposite.
[0073] The particle size of the TPP-loaded nano-cerium oxide material prepared in this embodiment is nanometer-level, and the particle size distribution is uniform and concentrated without obvious agglomeration.
[0074] In Examples 1-3, the triphenylphosphine group donor used is triphenylphosphine-polyethylene glycol-carboxyl polymer. In other embodiments, the triphenylphosphine group donor can be triphenylphosphine-polyethylene glycol-dihydrochlorin solution, triphenylphosphine-polydopamine solution or triphenylphosphine-polyethylene glycol-folic acid solution.
[0075] Example 4
[0076] An ophthalmic drug comprises the above-mentioned cerium dioxide nanocomposite with mitochondrial targeting activity.
[0077] The eye drops are used for the treatment of eye diseases by topical eye drops and intraocular administration. After intraocular injection or ocular surface instillation, they can be effectively delivered to the mitochondria in the damaged area of the posterior segment of the eye, more effectively catalyzing and removing reactive oxygen free radicals in the mitochondria, inhibiting the progression of posterior segment diseases from the source, and effectively treating and delaying diseases related to fundus oxidative stress damage.
[0078] The retina contains abundant mitochondria, especially the photoreceptor cells, which have a large number of mitochondria accumulated in the inner segments. These abundant mitochondria provide the necessary energy for visual signal transmission and intracellular material transport. With the increase of age and the influence of various pathological factors, the function of mitochondria will gradually decline, resulting in a decrease in ATP production, which in turn affects the function of photoreceptor cells, manifested as decreased vision or reduced visual sensitivity. Reactive oxygen species ROS, as a byproduct of the respiratory chain, are mainly produced in the mitochondria of cells. Excessive production of ROS by mitochondria and mitochondrial membrane permeabilization (MMP) are closely related to the occurrence of cell apoptosis. The retina produces ROS through its high oxygen consumption. Under physiological conditions, retinal cells have many redox regulatory systems to control the normal amount of ROS production. The mitochondrial electron transport chain (ETC) is the main source of reactive oxygen species (ROS) in aerobic cells, and mitochondria are also the target of ROS attack. Therefore, mitochondria are an important organelle in eukaryotic cells, which provide the energy required for cell life activities through oxidative respiration, and are also related to the production of oxygen free radicals in the human body and the regulation of cell death process.
[0079] Nano-cerium oxide has an antioxidant effect on cell, tissue and organ damage under various oxidative stress conditions. Nano-cerium oxide materials have also been used in the study of retinal neuronal cell protection. With the widespread application of intravitreal injection in the treatment of eye diseases in recent years, intravitreal injection of nano-cerium oxide has also been used in the study of related diseases. Studies on retinal degeneration have shown that 90 days after intravitreal injection of nano-cerium oxide, the presence of nano-cerium oxide was detected in retinal neurons and glia as well as in the retinal pigment epithelium (RPE) layer. In studies related to AMD, it has been shown that intravitreal injection of nano-cerium oxide can effectively inhibit laser-induced choroidal neovascularization by reducing the expression of ROS-induced vascular endothelial growth factor (VEGF). Nano-cerium oxide materials are used to more effectively treat and delay diseases related to fundus oxidative stress damage.
[0080] The embodiment of the present invention also conducted a functional verification experiment, and the results are as follows:
[0081] Figure 1This is a bar graph of the survival rate of 661W cells intervened by different concentrations of nano-cerium oxide in hypoxic environment. The Alamarblue method was used to detect the survival of 661W cells after intervention with different concentrations of nano-cerium oxide and mitochondrial targeted nano-cerium oxide materials in hypoxic environment for 24h and 48h. Group A, normoxic control group, group B, hypoxia group, group C, hypoxia + nano-cerium oxide intervention group, group D, hypoxia + mitochondrial targeted nano-cerium oxide intervention group; the drug doses were 1.25, 2.5, and 5ug / ml (C1 / D1, C2 / D2, and C3 / D3).
[0082] Note: Compared with group A in the same period, *P<0.05, **P<0.01, ***P<0.001, ****P<0.0001; compared with group B in the same period, #P<0.05, ##P<0.01; compared between two drugs of the same concentration, ▲P<0.05. Figure 2 Bar graph of ROS levels in hypoxic 661W cells after intervention with two nano-cerium oxide materials. Grouping: Group A: normoxic control group, Group B: hypoxia group, Group C: hypoxia + nano-cerium oxide intervention group, Group D: hypoxia + mitochondrial targeted nano-cerium oxide intervention group. Note: Compared with Group A in the same period, *P<0.05, **P<0.01, ****P<0.0001; compared with Group B in the same period, ##P<0.01, ###P<0.001; compared with Group C in the same period, ▲P<0.05.
[0083] Figure 4 -A TUNEL staining of cells in each group after intervention with two nano-cerium oxide materials (10X), grouping: Group A: normoxic control group, Group B: hypoxia group, Group C: hypoxia + nano-cerium oxide intervention group, Group D: hypoxia + mitochondrial targeted nano-cerium oxide intervention group. Ⅰ, 24 hours, Ⅱ, 48 hours.
[0084] Figure 4 -B Western blot and analysis of Bax, Bcl-2, and cleaved-caspase3 in each group of cells for 24 hours, grouping: Group A: normoxic control group, Group B: hypoxia model group, Group C: hypoxia + nano-cerium oxide intervention group, Group D: hypoxia + mitochondrial targeted nano-cerium oxide intervention group. Note: Compared with Group A, **P < 0.01, ***P < 0.001, ****P < 0.0001; compared with Group B, #P < 0.05, ##P < 0.01, ###P < 0.001; compared with Group C, ▲P < 0.05, ▲▲P < 0.01.
[0085] Figure 5Retinal mitochondrial labeling and nano-cerium oxide materials under fluorescence confocal microscopy at 7 days. The rats were prepared for experimental RD by subretinal injection of sodium hyaluronate at 7 days. Mitochondrial markers were used to label mitochondria in the retina. Group A: The mitochondria-rich areas were the ganglion cell layer, inner and outer plexiform layers, photoreceptor inner segments, and RPE base, among which photoreceptor mitochondria were concentrated in the photoreceptor inner segments; compared with group C, the expression of cerium oxide materials in group D was more significant in this area. (Group A, normal control group; Group B, RD control group; Group C, intravitreal injection of nano-cerium dioxide group; Group D, intravitreal injection of TPP-loaded nano-cerium dioxide group).
[0086] Figure 6 Figure 1 shows the occurrence of retinal apoptosis after intravitreal injection of cerium dioxide and TPP-loaded cerium dioxide at 1d, 3d, and 7d after RD. Compared with group B, the photoreceptor cell apoptosis index of group C and group D decreased significantly at 1d, 3d, and 7d after RD (P<0.05); compared with group C, the photoreceptor cell apoptosis index of group D decreased at 1d, 3d, and 7d after RD, and the difference between group D and group C was statistically significant at 3d after RD (P<0.05) (group B, RD control group; group C, intravitreal injection of nano-cerium dioxide; group D, intravitreal injection of TPP-loaded nano-cerium dioxide)
[0087] The above contents are only for explaining the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.
Claims
1. A cerium dioxide nanocomposite with mitochondrial targeting activity, characterized in that: The invention comprises nano cerium dioxide and triphenylphosphine modified on the nano cerium dioxide.
2. The cerium dioxide nanocomposite with mitochondrial targeting activity according to claim 1, characterized in that: The mass ratio of the cerium dioxide to triphenylphosphine is (5-15):(1-4).
3. A method for preparing a cerium dioxide nanocomposite with mitochondrial targeting activity according to claim 1 or 2, characterized in that: include: Step 1: Under alkaline conditions, a cerium nitrate solution is subjected to a two-step hydrothermal reaction to obtain nano-cerium dioxide; Step 2: modifying nano-cerium dioxide with triphenylphosphine to obtain a cerium dioxide nanocomposite.
4. The method for preparing a cerium dioxide nanocomposite with mitochondrial targeting activity according to claim 3, characterized in that: The preparation method of the nano cerium dioxide is as follows: Adding cerium nitrate solution into alkaline solution to carry out the first hydrothermal reaction, washing and drying to obtain nanorod precursor; The nanorod precursor solution is subjected to a second hydrothermal reaction and centrifugally dried to obtain nano-cerium dioxide.
5. The method for preparing a cerium dioxide nanocomposite with mitochondrial targeting activity according to claim 4, characterized in that: The alkaline solution is sodium hydroxide solution, potassium hydroxide solution, ammonia solution or ethylenediamine solution.
6. The method for preparing a cerium dioxide nanocomposite with mitochondrial targeting activity according to claim 4, characterized in that: The temperature of the first hydrothermal reaction is 100°C and the reaction time is 12-36h; The temperature of the second hydrothermal reaction is 160° C.-220° C., and the reaction time is 12-24 hours.
7. The method for preparing a cerium dioxide nanocomposite with mitochondrial targeting activity according to claim 1, characterized in that: The method for modifying triphenylphosphine on nano-cerium dioxide is as follows: The solution of the triphenylphosphine group donor is mixed evenly with the nano-cerium dioxide, and the mixture is allowed to stand for a certain period of time to modify the triphenylphosphine on the nano-cerium dioxide; In the modification of triphenylphosphine on the nano-cerium dioxide, the mass ratio of triphenylphosphine group to nano-cerium dioxide is: (5-15): (1-4).
8. The method for preparing a cerium dioxide nanocomposite with mitochondrial targeting activity according to claim 7, characterized in that: The triphenylphosphine group solution is a triphenylphosphine-polyethylene glycol-carboxyl polymer solution, a triphenylphosphine-polyethylene glycol-chlorin solution, a triphenylphosphine-polydopamine solution, and a triphenylphosphine-polyethylene glycol-folic acid solution.
9. The method for preparing a cerium dioxide nanocomposite with mitochondrial targeting activity according to claim 7, characterized in that: The mixture is allowed to stand for 12-16 hours in a light-proof condition to modify triphenylphosphine on the nano-cerium dioxide.
10. An ophthalmic drug, characterized in that: The invention comprises the cerium dioxide nanocomposite with mitochondrial targeting activity as described in any one of claims 1 to 9.