ZIF-8 nano-enzyme with Ce-luteolin coordination coating as well as preparation method and application of ZIF-8 nano-enzyme

Abstract

The invention relates to a ZIF-8 nano-enzyme with a Ce-luteolin coordination coating as well as a preparation method and application of the ZIF-8 nano-enzyme, and belongs to the technical field of biological medicines and nano-materials. The nano enzyme is constructed by adopting a step-by-step loading-coordination assembly strategy: firstly, synthesizing ZIF-8 nano particles as an inner core; then luteolin is introduced and adsorbed to pores and the surface of ZIF-8; finally, cerium ions are introduced, and the dense Ce-luteolin metal-organic coordination coating is formed on the surface of the ZIF-8 through in-situ growth by means of the strong coordination effect of phenolic hydroxyl groups and carbonyl groups in luteolin molecules and the cerium ions. The nano-enzyme has excellent SOD-like and CAT-like activities, and effectively inhibits foam cell formation, regulates endothelial cell senescence-related secretory phenotype (SASP) and alleviates DNA damage through an ROS removal-anti-inflammatory-anti-aging synergistic mechanism. The invention provides a new multi-target nano intervention strategy for the treatment of atherosclerosis.

Description

Technical Field

[0001] This invention belongs to the field of biomedicine and nanomaterials technology, specifically relating to a ZIF-8 nanozyme with a Ce-luteolin coordination coating, its preparation method and application, and especially to a Ce / Lut@ZIF-8 nano-drug delivery system with multiple enzyme activities and anti-inflammatory and anti-aging functions and its application in the treatment of atherosclerosis. Background Technology

[0002] Atherosclerosis (AS) is a chronic, systemic inflammatory vascular disease and a leading cause of cardiovascular and cerebrovascular death worldwide, including myocardial infarction and stroke. Current treatments primarily include lipid-lowering drugs (such as statins) and antiplatelet drugs, but these therapies only slow disease progression and cannot reverse plaque buildup or fundamentally address the vascular microenvironment disturbances caused by oxidative stress and cellular aging. Existing anti-inflammatory therapies have limited clinical efficacy and carry residual risks.

[0003] Studies have shown that senescent vascular endothelial cells play a key driving role in the development and progression of ankylosing spondylitis (AS). Senescent cells secrete a series of pro-inflammatory factors, chemokines, and proteases, known as the senescence-associated secretory phenotype (SASP), which further exacerbates vascular inflammation and plaque instability. Therefore, developing therapies that can simultaneously scavenge reactive oxygen species (ROS), inhibit inflammation, and target and eliminate or regulate senescent cells has become a highly promising therapeutic strategy.

[0004] Luteolin (Lut) is a natural flavonoid compound that has shown excellent anti-atherosclerotic potential through network pharmacology screening and molecular docking studies. However, luteolin suffers from drawbacks such as poor water solubility, low bioavailability, and rapid metabolism in vivo, which limit its clinical application. Furthermore, single-drug therapy is often insufficient to address the complex pathological environment of atherosclerosis (such as high oxidative stress).

[0005] Therefore, there is an urgent need to develop a novel nanocarrier system that can effectively deliver luteolin and synergistically exert its effects of scavenging ROS and regulating the cellular microenvironment through its own material properties. Summary of the Invention

[0006] This invention provides a ZIF-8 nanozyme (Ce / Lut@ZIF-8) co-loaded with luteolin and cerium. This system utilizes the variable valence properties of cerium to endow the carrier with enzyme activity and leverages the porous structure of ZIF-8 to efficiently load luteolin, achieving multi-target synergistic therapy of "ROS scavenging-anti-inflammatory-anti-aging". This addresses the limitations of existing atherosclerotic drugs in reversing plaque formation or fundamentally resolving vascular microenvironment disorders caused by oxidative stress and cellular aging.

[0007] According to a first aspect of the present invention, a ZIF-8 nanozyme with a Ce-luteolin coordination coating is provided, wherein the nanozyme has a ZIF-8 core, and the pores and surface of the core have a functionalized coating, wherein the functionalized coating is a chemically bound layer formed by luteolin and cerium ions through an in-situ chelation coordination reaction.

[0008] Preferably, the average particle size of the nanozyme is 70-120 nm.

[0009] Preferably, the cerium ion is Ce. 3+ and / or Ce 4+ .

[0010] According to another aspect of the present invention, a method for preparing the ZIF-8 nanozyme with the Ce-luteolin coordination coating is provided, comprising the following steps: (1) Disperse ZIF-8 nanoparticles in an organic solvent, and then add luteolin to load luteolin onto the pores and surface of ZIF-8 to obtain an intermediate. (2) Add a cerium source to the intermediate obtained in step (1) and utilize the phenolic hydroxyl and / or carbonyl groups in the luteolin molecule to perform in-situ chelation coordination with cerium ions to form a Ce-luteolin coordination coating in the ZIF-8 channels and surface. After solid-liquid separation, the ZIF-8 nanozyme with the Ce-luteolin coordination coating is obtained.

[0011] Preferably, in step (1), the ZIF-8 nanoparticles are prepared by adding a zinc source and 2-methylimidazole to a solvent for mixing and reaction, followed by centrifugation, washing and drying to obtain ZIF-8 nanoparticles.

[0012] Preferably, in step (1), the mass ratio of ZIF-8 to luteolin is (5~20):1; and the reaction time is 12-48 h.

[0013] According to another aspect of the present invention, the use of the ZIF-8 nanozyme with the Ce-luteolin coordination coating in the preparation of a drug for treating atherosclerosis is provided.

[0014] Preferably, the ZIF-8 nanozyme with Ce-luteolin coordination coating is used to combat vascular endothelial cell aging and regulate aging-related secretory phenotypes.

[0015] Preferably, the ZIF-8 nanozyme with a Ce-luteolin coordination coating is used to promote nitric oxide production in vascular endothelial cells and alleviate cell cycle arrest, thereby reducing DNA damage.

[0016] Preferably, the ZIF-8 nanozyme with Ce-luteolin coordination coating is used to scavenge intracellular reactive oxygen species and inhibit the expression of inflammatory factors.

[0017] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages: (1) This invention uses the biocompatible metal-organic framework ZIF-8 as the host, and loads luteolin; subsequently, it is doped with cerium ions (Ce). 3+ / Ce 4+ ), to construct a nanozyme framework with SOD-like and CAT-like activities.

[0018] (2) The preparation method of this invention adopts a stepwise loading-coordination assembly strategy. First, the ZIF-8 core is synthesized; then luteolin is introduced; finally, the abundant phenolic hydroxyl and carbonyl groups in the luteolin structure are used as "bridges" to strongly coordinate with exogenous cerium ions, forming a dense metal-organic coordination coating in situ on the ZIF-8 surface. The coordination coating strategy in this invention avoids the limitations of core-shell morphology. This coating is not a simple physical coating, but a dense layer formed by chemical bonding. On the one hand, it blocks the pores of ZIF-8 to prevent early drug leakage; on the other hand, the coating itself is rich in cerium, giving the material excellent enzyme-like activity. Even if no obvious thick shell is observed under electron microscopy, chemical characterization (XPS / EDS) can confirm the existence of this functional coating.

[0019] (3) The ZIF-8 nanozyme with Ce-luteolin coordination coating in this invention has a multi-target synergistic mechanism: achieving a triple synergistic treatment of "ROS scavenging (enzyme-like activity) - anti-inflammation (inhibition of foam cells) - anti-aging (protection of endothelium)". First aspect: It has ROS scavenging effect. Ce / Lut@ZIF-8 has multiple enzyme-like activities, which can catalyze the decomposition of superoxide anions and hydrogen peroxide, reducing the level of intracellular oxidative stress. Second aspect: It has anti-inflammatory effect. After the release of luteolin, it combines with the ROS scavenging effect to reduce the level of oxidative stress and block lipid phagocytosis, reducing the transformation of macrophages into foam cells. Third aspect: It has anti-aging effect. This nanozyme can promote the production of NO in endothelial cells, alleviate cell cycle arrest, reduce DNA damage, inhibit SASP secretion, and reshape vascular homeostasis.

[0020] (4) This invention utilizes the variable valence properties of cerium to endow the carrier with enzyme-like activity, and leverages the porous structure of ZIF-8 to efficiently load luteolin, achieving multi-target synergistic therapy of "ROS scavenging-anti-inflammatory-anti-aging". Specifically, the variable valence properties of cerium are: the unique 4f electron configuration of cerium constructs a highly efficient Ce... 3+ / Ce 4+ Redox cycle. Among them, Ce... 3+ As a reducing active center, it exerts SOD-like activity to scavenge O2· - And converted to Ce 4+Subsequently, Ce 4+ It exerts CAT-like activity to decompose H2O2 and regenerate it into Ce. 3+ This reversible valence cycle endows Ce / Lut@ZIF-8 with persistent, regenerable, broad-spectrum ROS scavenging capabilities. Attached Figure Description

[0021] Figure 1 A schematic diagram of the synthesis of Ce / Lut@ZIF-8.

[0022] Figure 2 Characterization of Ce / Lut@ZIF-8. (A) SEM characterization; (B) TEM characterization; (C) HAADF image and associated area elemental spectrum; (D) XRD spectrum; (E) XPS spectrum; (F) XPS analysis of Ce 3d.

[0023] Figure 3 The in vitro enzyme-like activity and full-spectrum free radical scavenging ability of Ce / Lut@ZIF-8 were compared. The effects of ZIF-8, luteolin, Ce ions, Lut@ZIF-8, and Ce / Lut@ZIF-8 on DPPH- (A), ABTS-+ (B), •OH (C), and •O2 were compared. - (D) Scavenging capacity (n = 3); (E) DPPH scavenging rate after treatment with different concentrations of Ce / Lut@ZIF-8; (F) ABTS-+ radical scavenging rate after treatment with different concentrations of Ce / Lut@ZIF-8; (G) ·OH scavenging rate after treatment with different concentrations of Ce / Lut@ZIF-8; (H) •O2 scavenging rate after treatment with different concentrations of Ce / Lut@ZIF-8. - Scavenging rate; (I) SOD-like activity of Ce / Lut@ZIF-8; (J) CAT-like activity of Ce / Lut@ZIF-8.

[0024] Figure 4Ce / Lut@ZIF-8 alleviates endothelial cell senescence. (A) ROS levels in HUVECs of different treatment groups (ZIF-8, Lut, Ce ions, Lut@ZIF-8 and Ce / Lut@ZIF-8) were detected by DCFH-DA FL probe after H2O2-induced senescence; (B) NO production in HUVECs of different treatment groups (ZIF-8, Lut, Ce ions, Lut@ZIF-8 and Ce / Lut@ZIF-8) were detected by DAF-FM DA FL probe after H2O2-induced senescence; (C) Representative images of SA-β-gal staining in HUVECs of different treatment groups (ZIF-8, Lut, Ce ions, Lut@ZIF-8 and Ce / Lut@ZIF-8) after H2O2-induced senescence; (D) mRNA expression levels of IL-6, IL-8, IL-1β and TNF-α in HUVECs of different treatments.

[0025] Figure 5 Ce / Lut@ZIF-8 reduces lipid accumulation and foam cell formation in Raw 264.7 cells. (A) Lipid production in Raw 264.7 cells of different treatment groups (ZIF-8, Lut, Ce ions, Lut@ZIF-8 and Ce / Lut@ZIF-8) after LPS induction was detected by Nile Red fluorescent dye; (B) ORO staining images of Raw 264.7 cells of different treatment groups (ZIF-8, Lut, Ce ions, Lut@ZIF-8 and Ce / Lut@ZIF-8) after LPS and ox-LDL induction.

[0026] Figure 6 The efficacy of Ce / Lut@ZIF-8 against atherosclerosis in apolipoprotein E- / - mice. (A) Schematic diagram of the construction and treatment regimen of AS model mice; (B) ORO staining images of aortic root sections of AS model mice after different treatments. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0028] This invention discloses a ZIF-8 nanozyme (Ce / Lut@ZIF-8) with a Ce-luteolin coordination coating. The nanozyme is a composite nanostructure comprising: ZIF-8 core: zeolite imidazoline framework-8 nanoparticles; Functionalized layer: a Ce-luteolin coordination coating applied to the surface of the ZIF-8 core; The coordination coating is a chemically bonded layer formed by the in-situ metal-polyphenol coordination reaction of luteolin molecules adsorbed on the ZIF-8 surface and exogenously introduced cerium ions (Ce); the nanozyme is simultaneously loaded with luteolin and cerium, and has superoxide dismutase (SOD) and catalase (CAT)-like activities.

[0029] In some embodiments, the nanozyme has an average particle size of 70-120 nm (preferably about 100 nm); the nanozyme retains the rhombic dodecahedral framework characteristics of ZIF-8, and its surface is functionalized through the coordination coating.

[0030] The present invention discloses a method for preparing ZIF-8 nanozymes (Ce / Lut@ZIF-8) with a Ce-luteolin coordination coating, which employs a stepwise loading-coordination assembly strategy and specifically includes the following steps: (1) Introduction of luteolin: The ZIF-8 nanoparticles obtained in step (1) are dispersed in the first solvent, luteolin is added, and the reaction is stirred to load luteolin into the pores and surface of ZIF-8 to obtain Lut@ZIF-8 intermediate. (2) Construction of coordination coating: The intermediate obtained in step (2) is dispersed in a second solvent, a cerium source is added, and the reaction is stirred; the phenolic hydroxyl groups and / or carbonyl groups in the luteolin molecules distributed on the surface react with cerium ions (Ce). 3+ / Ce 4+ Coordination occurs, and Ce-luteolin coordination coating is formed in situ in the ZIF-8 channels and surface, which is obtained after solid-liquid separation.

[0031] In some embodiments, the ZIF-8 nanoparticles are prepared by mixing a zinc source with 2-methylimidazole in a solvent, centrifuging, washing, and drying to obtain ZIF-8 nanoparticles.

[0032] Preferably, the zinc source is zinc nitrate hexahydrate, and the solvent is methanol; In some embodiments, in step (1), the first solvent is anhydrous ethanol; the mass ratio of ZIF-8 to luteolin is 5:1; and the reaction time is 24 hours. In some embodiments, in step (2), the second solvent is methanol; the cerium source is cerium nitrate; and during the reaction, cerium ions undergo in-situ chelation with surface luteolin.

[0033] The present invention relates to the application of ZIF-8 nanozymes (Ce / Lut@ZIF-8) with a Ce-luteolin coordination coating in the preparation of drugs for treating atherosclerosis (AS).

[0034] The present invention provides ZIF-8 nanozymes with Ce-luteolin coordination coating for anti-vascular endothelial cell aging and regulation of aging-related secretory phenotype (SASP). Specifically, it promotes the production of nitric oxide (NO) in vascular endothelial cells, alleviates cell cycle arrest, and reduces DNA damage.

[0035] The present invention provides a ZIF-8 nanozyme with a Ce-luteolin coordination coating for scavenging intracellular reactive oxygen species (ROS) and inhibiting the expression of inflammatory factors.

[0036] The following are specific examples.

[0037] Example 1: Preparation of Ce / Lut@ZIF-8 nanozymes with coordination coating Figure 1 This is a schematic diagram of the synthesis of Ce / Lut@ZIF-8 according to the present invention. The present invention employs a stepwise loading-coordination assembly strategy to construct the system: (1) Synthesis of ZIF-8 core: Zinc nitrate hexahydrate and 2-methylimidazole were dissolved in methanol, mixed and stirred, the precipitate was collected by centrifugation, washed with methanol, and dried under vacuum to obtain ZIF-8 nanoparticles.

[0038] (2) Luteolin (Lut) loading: Weigh 500 mg of ZIF-8 and disperse it in 20 mL of anhydrous ethanol, then sonicate for 20 min. Weigh 100 mg of luteolin and dissolve it in 10 mL of anhydrous ethanol, then slowly add it to the ZIF-8 suspension. Stir at room temperature for 24 h to allow the luteolin molecules to fully diffuse into the ZIF-8 channels and adsorb onto the particle surface, forming the Lut@ZIF-8 intermediate. Collect the solid by centrifugation, wash it three times with anhydrous ethanol, and vacuum dry it to obtain luteolin@ZIF-8.

[0039] (3) In-situ growth of the coordination coating: 100 mg Lut@ZIF-8 was redispersed in 20 mL of methanol and ultrasonically dispersed for 20 min. Under vigorous stirring, 3 mL of cerium nitrate solution (38.4 mM) was slowly added dropwise, and stirring continued for 6 h after the addition was complete. Under stirring conditions, the Ce in the solution... 3+ An in-situ coordination reaction (based on the major functional groups phenolic hydroxyl and carbonyl) occurs between Ce and luteolin molecules adsorbed on the surface of ZIF-8 particles, resulting in the self-assembly of a Ce-luteolin coordination coating on the particle surface. After the reaction, Ce / Lut@ZIF-8 is obtained by centrifugation, washing, and drying, and then stored at 4 °C.

[0040] Example 2: Structural and Morphological Characterization Morphological characterization (SEM / TEM): The results showed that the synthesized Ce / Lut@ZIF-8 nanozyme had a uniform dodecahedral structure with an average particle size of about 100 nm. Figure 2 The morphological characterization results (TEM and SEM) of AB showed that Ce / Lut@ZIF-8 perfectly preserved the typical rhombic dodecahedral structure of ZIF-8, with a particle size of about 80-110 nm, and the surface was covered with a uniform amorphous shell.

[0041] Structural characterization (XRD): The XRD pattern shows typical ZIF-8 crystal characteristic peaks and no obvious impurity peaks. Figure 2 XRD analysis of the D in the image showed that the diffraction peak positions of Ce / Lut@ZIF-8 were consistent with those of the original ZIF-8 (JCPDS: 00-062-1030), confirming the integrity of the support crystal structure. The characteristic peak intensities at 2θ = 7.3°, 10.4°, 12.7°, 16.4°, and 17.9° decreased and the peak shapes broadened, indicating the formation of an amorphous coating on the surface. No Ce oxide-related impurity peaks were observed, confirming the presence of Ce oxide. 3+ It coordinates with luteolin in a highly dispersed form.

[0042] XPS analysis confirmed the successful introduction of Ce and its presence. 3+ and Ce 4+ Mixed valence states are the basis for its enzyme-like activity. Figure 2 XPS analysis of E in Ce / Lut@ZIF-8 revealed a distinct Ce 3d characteristic peak (880-920 eV), while the enhanced intensity of the C 1s and O 1s peaks confirmed the successful loading of luteolin and Ce. 3+ The coordination between Zn and the phenolic hydroxyl groups of luteolin. The stable Zn 2p peak indicates the integrity of the ZIF-8 host structure, verifying the Ce... 3+ A coating was successfully constructed on the ZIF-8 surface using luteolin and luteolin. Figure 2 The high-resolution XPS spectrum of Ce 3d in Ce / Lut@ZIF-8 shows that cerium is present in Ce as a precipitate. 3+ (21.63%) and Ce 4+ (78.37%) Mixed valence states exist, Ce 3+ / Ce 4+ The coexistence of these elements gives the material reversible redox properties (Ce). 3+ →Ce 4+ +e - It can scavenge free radicals through electron transfer, giving it enzyme-like activity and the ability to scavenge ROS.

[0043] Coating analysis: Compared to the smooth pure ZIF-8, the Ce / Lut@ZIF-8 surface is covered with a uniform material (i.e., a coordination coating), which increases the surface roughness. Due to the tight bonding between the coordination coating and the substrate and the high degree of interfacial fusion between the two due to their organic-inorganic hybrid properties, changes in edge contours and the presence of an amorphous layer can be observed through TEM comparison.

[0044] Composition verification: EDS mapping showed that Zn was concentrated in the core, while Ce completely covered the overall particle outline, confirming the successful coating of the coordination coating. XPS analysis further confirmed the formation of coordination bonds between Ce and O. Figure 2 The elemental mapping spectrum of C in the sample confirms that C, N, O and Ce elements are uniformly distributed in the particles, indicating that the active component has been successfully loaded.

[0045] Example 3: Evaluation of in vitro enzyme-like activity and full-spectrum free radical scavenging performance of Ce / Lut@ZIF-8 (1) In order to comprehensively evaluate the antioxidant potential of the Ce / Lut@ZIF-8 nanozyme prepared in this invention under in vitro conditions, and to verify its "carrier-drug-ion" ternary synergistic mechanism, this embodiment selected four representative free radical models for testing: including ABTS free radical cation (ABTS· + ) and DPPH radicals (DPPH·), as well as hydroxyl radicals (·OH) and superoxide anion radicals (O2·) as physiologically relevant reactive oxygen species (ROS) models. - This nanozyme exhibits a significant dose-dependent scavenging effect on all four of the aforementioned free radicals. Figure 3 The AH assay showed that Ce / Lut@ZIF-8 exhibited a significant dose-dependent scavenging effect on all four free radicals mentioned above. Notably, at the same concentration, the scavenging efficiency of Ce / Lut@ZIF-8 was significantly superior to that of the single components (ZIF-8, free Lut, Ce ions) and Lut@ZIF-8.

[0046] (2) Ce / Lut@ZIF-8 showed significant SOD-like and CAT-like activities as detected by SOD kit and CAT kit. Figure 3 The IJ study showed that Ce / Lut@ZIF-8 exhibited the highest SOD-like and CAT-like activities at the same concentration. This superior performance strongly confirms the successful construction of the "carrier-drug-ion" ternary synergistic antioxidant mechanism in this system: First, Ce... 3+ / Ce 4+The efficient redox cycle endows the material with sustained SOD-like and CAT-like enzyme activity; secondly, the abundant phenolic hydroxyl groups in the luteolin structure provide direct electron donors to neutralize free radicals; finally, the high specific surface area porous framework of ZIF-8 not only achieves efficient loading of active components but also significantly increases the contact area between active sites and free radicals. Most importantly, it targets the most destructive ·OH radical in living organisms and O2·, which is the initiating species of oxidative cascade reactions. - Ce / Lut@ZIF-8 exhibited superior scavenging performance. This highly efficient scavenging ability of physiological ROS suggests that Ce / Lut@ZIF-8 has the potential to effectively alleviate oxidative stress in cells and the in vivo microenvironment, thereby blocking the pathological process of atherosclerosis.

[0047] (3) In the H2O2-induced cell damage model, the Ce / Lut@ZIF-8 treatment group significantly reduced intracellular ROS levels (detected by the DCFH-DA probe). (See results below) Figure 4 A) Example 4: In vitro anti-AS and anti-aging activities Anti-aging: In a 400 μm H2O2-induced senescence model of HUVECs endothelial cells, the nanozyme treatment group significantly reduced the number of SA-β-gal positive cells, upregulated NO production, and downregulated the expression of SASP-related factors. Figure 4 In the study, the total ROS level in cells was detected using the DCFH-DA fluorescent probe. The results showed that the fluorescence intensity of the Ce / Lut@ZIF-8 treatment group was significantly lower than that of the control groups such as ZIF-8, free Lut, Ce ions, and Lut@ZIF-8. This indicates that through the synergistic effect of Ce ions and Lut, this nanosystem can most efficiently remove excess ROS in cells. Figure 4 In this study, the ability of Ce / Lut@ZIF-8 to restore NO generation in HUVECs was investigated using the DAF-FM DA fluorescent probe. The results showed that, compared with the H2O2 model group and other control groups (ZIF-8, Lut, Ce ions, and Lut@ZIF-8), the Ce / Lut@ZIF-8 treatment group exhibited a significantly enhanced green fluorescence signal, indicating that it can effectively reverse oxidative stress-induced NO depletion. Figure 4 The anti-aging efficacy of Ce / Lut@ZIF-8 was further verified using SA-β-Gal staining experiments. The results showed that Ce / Lut@ZIF-8 treatment significantly reduced SA-β-Gal positive signal in HUVECs, indicating that it can effectively block the aging process mediated by lysosomal dysfunction. Figure 4qPCR analysis of D in the study showed that Ce / Lut@ZIF-8 significantly inhibited H2O2-induced expression of SASPs such as IL-6, IL-1β, IL-8, and TNF-α, effectively blocking the harmful effects of senescent cells on the surrounding microenvironment.

[0048] Anti-inflammatory: In LPS-induced Raw264.7 macrophages, Ce / Lut@ZIF-8 significantly inhibited lipid accumulation and reduced oxidized low-density lipoprotein (ox-LDL)-induced lipid accumulation (Oil Red O staining). Figure 5 Cell morphology was observed by Oil Red O (ORO) staining in A, and the cells were further analyzed by LPS (100 ng / mL). -1 ) and ox-LDL (100 μg mL) -1 After 12 hours of combined induction, numerous red lipid droplets appeared in the cytoplasm of the model group, exhibiting typical foaming characteristics; however, the number and area of ​​lipid droplets in the Ce / Lut@ZIF-8 treatment group were significantly reduced. To further quantify this effect, intracellular cholesterol content was measured using a Nile Red fluorescent probe. Consistent with the ORO results, the Ce / Lut@ZIF-8 treatment group showed a significantly reduced red fluorescence intensity (…). Figure 5 The presence of B in the sample strongly confirms that it can effectively inhibit lipid accumulation and block the maturation process of foam cells.

[0049] Example 5: In vivo therapeutic effect A high-fat diet-induced asthma model was established using ApoE- / - mice. Following tail vein injection of Ce / Lut@ZIF-8, gross Oil Red O staining and section staining of the aorta showed that the treatment group exhibited a significant reduction in plaque area and an increase in collagen content (increased plaque stability). Figure 6 A in the figure shows the ApoE induced by a high-fat diet. - / - Mouse model construction and treatment with different drugs. Figure 6 B in the image shows Oil Red O staining of aortic root sections from different treatment groups. Compared with other groups (ZIF-8, Lut, Ce ions, and Lut@ZIF-8), the Ce / Lut@ZIF-8 treatment group significantly reduced the lipid core area within the plaque, indicating that it can effectively inhibit the progression of atherosclerotic plaques.

[0050] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A ZIF-8 nanoszyme with Ce-luteolin coordination coating, characterized in that, The nano-enzyme takes ZIF-8 as a core, and the pores and surface of the core have a functional coating formed by in-situ chelation coordination reaction of luteolin and cerium ions.

2. The ZIF-8 nanomachine with Ce-lutelin coordination coating of claim 1, characterized in that, The average particle size of the nano-enzyme is 70-120 nm.

3. The ZIF-8 nanomachine with Ce-lutelin coordination coating of claim 1, wherein, The cerium ion is Ce 3+ and / or Ce 4+ .

4. The method for preparing ZIF-8 nanoszyme with Ce-luteolin coordination coating according to any one of claims 1-3, characterized in that, The method comprises the following steps: (1) dispersing ZIF-8 nanoparticles in an organic solvent, and then adding luteolin to load the luteolin in the pores and surface of the ZIF-8 to obtain an intermediate; (2) adding a cerium source to the intermediate obtained in step (1), and using the phenolic hydroxyl and / or carbonyl in the luteolin molecules to perform in-situ chelation coordination with cerium ions to form a Ce-luteolin coordination coating in-situ on the pores and surface of the ZIF-8, and after solid-liquid separation, the ZIF-8 nano-enzyme with the Ce-luteolin coordination coating is obtained.

5. The method of claim 4, wherein the ZIF-8 nanoszyme with Ce-luteolin coordination coating is prepared by the following steps: In step (1), the ZIF-8 nanoparticles are prepared by mixing a zinc source and 2-methyl imidazole in a solvent, and after centrifugation, washing and drying, the ZIF-8 nanoparticles are obtained.

6. The method of preparation of ZIF-8 nanoszyme with Ce-luteolin coordination coating as claimed in claim 4 wherein, In step (1), the mass ratio of the ZIF-8 to luteolin is (5-20):1, and the reaction time is 12-48 h.

7. Use of the ZIF-8 nano-enzyme with the Ce-luteolin coordination coating in the preparation of a drug for treating atherosclerosis according to any one of claims 1-3.

8. Use according to claim 7, wherein the compound is ###0002### The ZIF-8 nano-enzyme with the Ce-luteolin coordination coating is used for resisting vascular endothelial cell aging and regulating the senescence-associated secretory phenotype.

9. Use according to claim 8, wherein the compound is ###0002### The ZIF-8 nano-enzyme with the Ce-luteolin coordination coating is used for promoting the generation of nitric oxide of vascular endothelial cells and relieving cell cycle arrest, thereby reducing DNA damage.

10. The use according to claim 7, wherein the compound is ###00003### or a pharmaceutically acceptable salt thereof. The ZIF-8 nano-enzyme with the Ce-luteolin coordination coating is used for eliminating intracellular reactive oxygen species and inhibiting the expression of inflammatory factors.

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