Nanocomposite material capable of adjusting synaptic plasticity and preparation method thereof

Abstract

The invention discloses a nano composite material capable of adjusting synaptic plasticity and a preparation method thereof, and belongs to the technical field of nano materials. Polylactic acid and polyamino acid form a copolymer, the nano composite material is formed, the polyamino acid is subjected to graft modification, and a glutamic acid receptor inhibitor passes through the polyamino acid terminal, so that the synaptic plasticity can be adjusted. By regulating and controlling the synapses, the transient sensitization of the synapses is accurately intervened, and the abnormal expression of long-term enhancement of the synapses of the central nervous system is controlled, so that the chronic oral pain is relieved.

Description

Technical Field

[0001] The invention belongs to the technical field of nanomaterials, and specifically refers to a nanocomposite material capable of regulating synaptic plasticity and a preparation method thereof. Background Art

[0002] Synaptic plasticity refers to the ability of synaptic strength and function in the nervous system to adjust with activity or environmental changes. It is the biological basis of learning, memory, and neural network remodeling. Synaptic plasticity involves complex mechanisms such as neurotransmitter release, dynamic regulation of postsynaptic membrane receptors, and calcium signaling. Key molecules include NMDA receptors and AMPA receptors, which dominate processes such as long-term potentiation (LTP) and long-term depression (LTD), respectively. In addition, neurotrophic factors (such as brain-derived neurotrophic factor, BDNF) also play an important role in promoting synaptic growth and functional plasticity. Regulation of synaptic plasticity is one of the core research topics in the field of neuroscience, and its application areas include the treatment of neurological diseases, functional reconstruction after stroke, and neural enhancement. Nanocomposites can regulate synaptic plasticity in a precise and dynamic manner due to their unique physical and chemical properties. They have the following advantages: High surface area and multifunctionality: Nanocomposites can be loaded with a variety of functional molecules, such as drugs, genes or neurotrophic factors, to achieve multimodal regulation of neurons; Targeted delivery capability: Through functional design, nanomaterials can target specific neurons or synaptic locations to avoid off-target effects and reduce side effects; Responsive regulation: Nanomaterials can respond to light, electricity, magnetic fields or chemical stimulation to regulate synaptic activity, and are suitable for dynamic neural regulation. However, targeted nanomaterials also have some defects, such as insufficient targeting: more precise functional molecules need to be designed to achieve precise positioning of specific neurons or synapses; Biocompatibility and long-term stability: how to reduce the immune response of the material while ensuring its stability in the body. Chronic oral pain is a type of complex pain that exists continuously or intermittently, including trigeminal neuralgia, temporomandibular joint disorder syndrome, burning sensation syndrome, etc. The matrix central sensitization of chronic oral pain means that under the chronic pain state, the synaptic transmission function of the central nervous system (especially the spinal cord and brainstem) is enhanced, so that the pain signal is amplified, and pain will be perceived even without obvious peripheral stimulation. Summary of the invention

[0003] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a nanocomposite material capable of regulating synaptic plasticity and a preparation method thereof. The present invention forms a nanocomposite material by forming a copolymer from polylactic acid and polyamino acid, grafting and modifying the polyamino acid, and adding a glutamate receptor inhibitor to the end of the polyamino acid to regulate the synapse, precisely intervene in the synaptic transition sensitization, and control the abnormal manifestations of long-term potentiation of synapses in the central nervous system, so as to relieve chronic oral pain.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] The present invention provides a method for preparing a nanocomposite material capable of regulating synaptic plasticity, which specifically comprises the following steps:

[0006] S1. Put 5,6-diaminouracil in a flask, add glycolic acid and mix well, raise the reaction temperature to 120-130°C, stir the reaction at 100-120rpm, cool to room temperature after 30-40min, precipitate with ethanol / ether mixed solution, filter, add precipitate 1 to ethanol aqueous solution, add 10wt% NaOH aqueous solution dropwise at 0.15mL / min, stir at 120-150rpm, raise the reaction temperature to 80-90°C, react for 2-3h, cool, adjust the pH of the reaction system to 1.0-2.0 with 1M HCl, collect precipitate 2 by filtration, wash with deionized water, and dry to obtain 8-hydroxymethylxanthine;

[0007] Preferably, in step S1, the mass ratio between the 5,6-diaminouracil and glycolic acid is 1.3-1.5:1;

[0008] Preferably, in step S1, the mass concentration of the precipitate 1 in the ethanol aqueous solution is 0.1-0.15 g / mL;

[0009] Preferably, in step S1, the mass volume ratio between the precipitate 1 and the NaOH aqueous solution is 0.15-0.2 g / mL;

[0010] S2, placing the 8-hydroxymethylxanthine and triethylamine prepared in step S1 in a flask, dissolving them in DMF, introducing flowing nitrogen, adding chloroacetic acid dropwise, raising the reaction temperature to 40-50°C, reacting for 8-10 hours, adding 4-chlorobenzyl bromide and potassium carbonate, raising the reaction temperature to 80-90°C, reacting for 2-3 hours, adding deionized water for dilution, extracting with ethyl acetate, taking the organic phase and drying it with anhydrous sodium sulfate, purifying it, and obtaining the NMDA antagonist recognition body;

[0011] Preferably, in step S2, the mass volume ratio between the 8-hydroxymethylxanthine and triethylamine is 0.4-0.5 g / mL;

[0012] Preferably, in step S2, the mass concentration of 8-hydroxymethylxanthine in DMF is 0.03-0.05 g / mL;

[0013] Preferably, in step S2, the mass ratio between 8-hydroxymethylxanthine and chloroacetic acid is 0.6-0.8:1;

[0014] Preferably, in step S2, the mass ratio between the 4-chlorobenzyl bromide and potassium carbonate is 0.7-0.8:1;

[0015] Preferably, in step S2, the mass ratio between 8-hydroxymethylxanthine and 4-chlorobenzyl bromide is 0.6-0.7:1

[0016] S3, placing the NMDA antagonist recognition body prepared in step S2 in DMF, stirring until completely dissolved, transferring to an ice water bath, adding DCC and HOBt, mixing evenly, adding BOC-D-glutamine, placing at room temperature, stirring at a speed of 150-180 rpm, reacting for 12-18 hours, filtering, collecting the filtrate, diluting with deionized water, extracting with ethyl acetate, separating the organic phase, washing the organic phase with a saturated sodium chloride solution, drying with anhydrous sodium sulfate, and purifying to obtain the NMDA antagonist recognition body grafted amino acid;

[0017] Preferably, in step S3, the mass concentration of the NMDA antagonist recognition body in DMF is 0.03-0.05 g / mL;

[0018] Preferably, in step S3, the mass ratio between DCC and HOBt is 1:0.7-0.9;

[0019] Preferably, in step S3, the mass ratio between the NMDA antagonist recognition body and DCC is 1.3-1.5:1;

[0020] Preferably, in step S3, the ratio of the NMDA antagonist recognition body to BOC-D-glutamine is 0.6-0.8:1;

[0021] S4, placing the NMDA antagonist recognition body grafted amino acid prepared in step S3 in anhydrous THF, adding SOCl2, stirring at room temperature at a speed of 200-220 rpm, reacting for 40-60 minutes, precipitating with anhydrous ether, filtering, collecting the precipitate, washing with anhydrous ether, and drying to obtain NMDA antagonist recognition body grafted amino acid-NCA;

[0022] Preferably, in step S4, the mass concentration of the NMDA antagonist recognition body grafted amino acid in anhydrous THF is 2-3 mg / mL;

[0023] Preferably, in step S4, the mass volume ratio of the NMDA antagonist recognition body grafted amino acid to SOCl2 is 3-5 g / mL;

[0024] S5, placing the NMDA antagonist recognition body grafted amino acid-NCA prepared in step S4 in DMF, introducing flowing nitrogen, adding ethylenediamine, raising the temperature to 40-50°C, reacting for 48-54 hours, acidifying and precipitating with 1 mol / L HCl solution, filtering, collecting the precipitate, and drying to obtain the NMDA antagonist recognition body grafted polyamino acid;

[0025] Preferably, in step S5, the mass concentration of the NMDA antagonist recognition body grafted amino acid-NCA in anhydrous DMF is 3-5 mg / mL;

[0026] Preferably, in step S5, the mass volume ratio between the NMDA antagonist recognition body grafted amino acid-NCA and ethylenediamine is 4-5 g / mL;

[0027] S6, dissolving PLA in chloroform, adding NHS and EDC·HCl, mixing well, introducing flowing nitrogen, stirring at 250-300 rpm under nitrogen atmosphere, reacting for 4-5 hours, adding the NMDA antagonist recognition body grafted polyamino acid prepared in step S5, continuing stirring and reacting for 48-54 hours, placing in DMSO for dialysis for 3 days, transferring to deionized water for dialysis for 3 days, and freeze-drying to obtain a nanocomposite material;

[0028] Preferably, in step S6, the mass concentration of PLA in chloroform is 0.02-0.04 g / mL;

[0029] Preferably, in step S6, the added mass of NHS is 10%-12% of the mass of PLA;

[0030] Preferably, in step S6, the added mass of EDC·HCl is 15%-20% of the mass of PLA;

[0031] Preferably, in step S6, the mass ratio between the NMDA antagonist receptor grafted polyamino acid and PLA is 0.7-0.8:1.

[0032] The present invention also provides a nanocomposite material capable of regulating synaptic plasticity, which is prepared according to the method.

[0033] The beneficial effects achieved by the present invention are as follows:

[0034] The present invention provides a nanocomposite material capable of regulating synaptic plasticity and a preparation method thereof. The present invention forms a nanocomposite material by forming a copolymer from polylactic acid and polyamino acid, grafting and modifying the polyamino acid, and providing a glutamate receptor inhibitor at the end of the polyamino acid to regulate the synapse, precisely intervene in the synaptic transition sensitization, and control the abnormal manifestation of long-term potentiation of the synapse of the central nervous system, so as to relieve chronic oral pain. In the present invention, 5,6-diaminouracil is used as a starting material, and a side chain group having an inhibitory effect on the glutamate receptor is synthesized. The aromatic ring interacts with the amino acid receptor through hydrophobic interaction, and the benzyl group on the side chain can form a π-π stacking effect with the amino acid residue on the glutamate receptor, thereby improving the inhibitory activity on the glutamate receptor, regulating synaptic transmission through targeted recognition and inhibition of the glutamate receptor, and effectively controlling the excessive propagation of pain signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a hydrogen nuclear magnetic resonance spectrum image of the nanocomposite material prepared in Example 1 of the present invention;

[0036] Figure 2 The encapsulation efficiency and drug loading of the nanocomposite materials prepared in Examples 1-3 and Comparative Examples 1-2 of the present invention;

[0037] Figure 3 It is a comparison diagram of the in vivo hippocampal field potential of mice in the treatment groups of Example 1-3 and Comparative Example 1-2.

[0038] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0040] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0041] The experimental methods in the following examples are conventional methods unless otherwise specified; the experimental materials and test strains used in the following examples are purchased from commercial channels unless otherwise specified.

[0042] Example 1

[0043] This embodiment provides a method for preparing a nanocomposite material capable of regulating synaptic plasticity, which specifically comprises the following steps:

[0044] S1. Accurately weigh 2.6 g of 5,6-diaminouracil and place it in a beaker. Add 2.0 g of glycolic acid and mix well. Raise the reaction temperature to 120°C and stir at 120 rpm for 30 min. After the reaction system is cooled to room temperature, add a mixed solution of ethanol and ether in a volume ratio of 1:3 to the reaction system for precipitation. After filtering, collect the precipitate and wash it repeatedly with anhydrous ethanol three times. Take 3.0 g of the precipitate and dissolve it in 30 mL of ethanol aqueous solution (V 乙醇 :V 水 =2:1), add 10wt% NaOH aqueous solution 15mL at a rate of 0.15mL / min, stir at a rate of 150rpm, raise the reaction temperature to 90°C, react for 2h, wait for the reaction system to cool to room temperature, adjust the pH of the reaction system to 1.0 with 1M HCl, filter, collect precipitate 2, wash repeatedly with deionized water three times, and dry to obtain 8-hydroxymethylxanthine;

[0045] S2. Accurately weigh 2.5 g of 8-hydroxymethylxanthine prepared in step S1 and place it in a flask, add 6.25 mL of triethylamine, mix it slightly, add 50 mL of DMF to dissolve the reactant, introduce flowing nitrogen, and then add 3.1 g of chloroacetic acid under a nitrogen atmosphere. After mixing, raise the reaction temperature to 50° C., react for 8 h, add 4.2 g of 4-chlorobenzyl bromide and 6 g of potassium carbonate, mix them evenly, raise the reaction temperature to 90° C., react for 2 h, dilute with 500 mL of deionized water, extract with ethyl acetate, take the organic phase and dry it with anhydrous sodium sulfate overnight, remove the ethyl acetate, and purify to obtain the NMDA antagonist recognition body;

[0046] S3, accurately weigh 2.0 g of the NMDA antagonist recognition body prepared in step S2 into a flask, add 50 mL of DMF, stir at 150 rpm until the reactant is completely dissolved, place in an ice water bath, add 1.5 g of DCC and 1.1 g of HOBt, continue to stir and mix evenly, add 2.5 g of BOC-D-glutamine, stir and react at room temperature at 180 rpm, react for 12 h, filter, collect the filtrate, add 200 mL of deionized water to dilute, extract with ethyl acetate, separate the organic phase, wash with saturated sodium chloride solution, dry with anhydrous sodium sulfate, remove ethyl acetate, and purify to obtain NMDA antagonist recognition body grafted amino acid;

[0047] S4, accurately weigh 0.1 g of the NMDA antagonist recognition body grafted amino acid prepared in step S3, put it into a flask, add 50 mL of anhydrous THF, add 20 μL of SOCl2, stir at room temperature at a speed of 220 rpm, react for 40 min, filter, collect the precipitate, wash it repeatedly with anhydrous ether three times, and dry it to obtain the NMDA antagonist recognition body grafted amino acid;

[0048] S5. Accurately weigh 0.1 g of the NMDA antagonist recognition body grafted amino acid-NCA prepared in step S4 and place it in a flask, add it to 20 mL of DMF, mix until dissolved, introduce flowing nitrogen, add 25 μL of ethylenediamine as an initiator, raise the reaction temperature to 50°C, react for 48 hours, acidify and precipitate with 1 mol / L HCl solution, filter, collect the precipitate, wash with deionized water until neutral, and dry to obtain the NMDA antagonist recognition body grafted polyamino acid;

[0049] S6. Accurately weigh 0.5 g of PLA, place it in a flask, add 25 mL of chloroform, add 0.05 g of NHS and 0.09 g of EDC•HCl, mix well, introduce flowing nitrogen, stir at 250 rpm under nitrogen atmosphere, perform activation reaction for 4 hours, accurately weigh 0.4 g of the NMDA antagonist recognition body grafted polyamino acid prepared in step S5, continue stirring and reacting for 48 hours, place it in a 5 kDa dialysis bag, dialyze it with DMSO for 3 days, transfer it to deionized water and continue dialyzing for 3 days, and freeze-dry it to obtain a nanocomposite material;

[0050] This embodiment also provides a nanocomposite material capable of regulating synaptic plasticity, which is prepared according to the above preparation method.

[0051] Figure 1This is the hydrogen nuclear magnetic resonance spectrum image of the nanocomposite material prepared in Example 1 of the present invention. After analysis, the hydrogen spectrum data of the nanocomposite material prepared in Example 1 is 1H NMR (400 MHz, DMSO-d6) δ 11.33 (s, 1H), 7.56 (d, J = 7.5 Hz, 1H), 7.50 (s, 1H), 7.38 (t, J = 7.8 Hz, 1H), 7.24 (d, J= 7.6 Hz, 1H), 5.64 (s, 2H), 5.25 (s, 2H), 3.42 (s, 3H), 1.90 (s, 3H).

[0052] Example 2

[0053] This embodiment provides a method for preparing a nanocomposite material capable of regulating synaptic plasticity, which specifically comprises the following steps:

[0054] S1. Accurately weigh 3 g of 5,6-diaminouracil and put it in a beaker. Add 2.0 g of glycolic acid and mix well. Raise the reaction temperature to 130°C and stir at 150 rpm. After 40 min of reaction, wait for the reaction system to cool to room temperature. Add a mixed solution of ethanol and ether in a volume ratio of 1:3 to the reaction system for precipitation. After filtering, collect the precipitate and wash it three times with anhydrous ethanol. Take 3.0 g of the precipitate and dissolve it in 20 mL of ethanol aqueous solution (V ethanol: V water = 2:1). Add it dropwise to 20 mL of 10 wt% NaOH aqueous solution at a rate of 0.15 mL / min. Stir at 120 rpm and raise the reaction temperature to 85°C. After 3 h of reaction, wait for the reaction system to cool to room temperature. Adjust the pH of the reaction system to 1.5 with 1 M HCl. Filter and collect the precipitate. After washing it three times with deionized water, dry it to obtain 8-hydroxymethylxanthine.

[0055] S2. Accurately weigh 2.5 g of 8-hydroxymethylxanthine prepared in step S1 and place it in a flask. Add 5 mL of triethylamine and mix it slightly. Then, add 83 mL of DMF to dissolve the reactant. After flowing nitrogen, add 4.2 g of chloroacetic acid under a nitrogen atmosphere. After mixing evenly, raise the reaction temperature to 50° C. After reacting for 8 h, add 3.6 g of 4-chlorobenzyl bromide and 4.8 g of potassium carbonate. After mixing evenly, raise the reaction temperature to 90° C. After reacting for 2 h, dilute with 500 mL of deionized water, extract with ethyl acetate, take the organic phase and dry it with anhydrous sodium sulfate overnight, remove the ethyl acetate, and purify to obtain an NMDA antagonist recognition body;

[0056] S3, accurately weigh 2.1 g of the NMDA antagonist recognition body prepared in step S2 into a flask, add 70 mL of DMF, stir at 150 rpm until the reactant is completely dissolved, place in an ice-water bath, add 1.5 g of DCC and 1.35 g of HOBt, continue to stir and mix evenly, add 3.0 g of BOC-D-glutamine, stir and react at room temperature at 150 rpm, react for 18 h, filter, collect the filtrate, add 200 mL of deionized water to dilute, extract with ethyl acetate, separate the organic phase, wash with saturated sodium chloride solution, dry with anhydrous sodium sulfate, remove ethyl acetate, and purify to obtain NMDA antagonist recognition body grafted amino acid;

[0057] S4, accurately weigh 0.12 g of the NMDA antagonist recognition body grafted amino acid prepared in step S3, put it into a flask, add it into 40 mL of anhydrous THF, add 40 μL of SOCl2, stir and react at room temperature at a speed of 200 rpm, react for 60 min, filter, collect the precipitate, wash it repeatedly with anhydrous ether three times, and dry it to obtain the NMDA antagonist recognition body grafted amino acid;

[0058] S5. Accurately weigh 0.1 g of the NMDA antagonist recognition body grafted amino acid-NCA prepared in step S4 and place it in a flask, add it to 25 mL of DMF, mix until dissolved, introduce flowing nitrogen, add 20 μL of ethylenediamine as an initiator, raise the reaction temperature to 40°C, react for 54 hours, acidify and precipitate with 1 mol / L HCl solution, filter, collect the precipitate, wash with deionized water until neutral, and dry to obtain the NMDA antagonist recognition body grafted polyamino acid;

[0059] S6. Accurately weigh 0.4 g of PLA, place it in a flask, add 10 mL of chloroform, add 0.048 g of NHS and 0.08 g of EDC•HCl, mix well, introduce flowing nitrogen, stir at 280 rpm under nitrogen atmosphere, perform activation reaction for 5 h, accurately weigh 0.28 g of the NMDA antagonist recognition body grafted polyamino acid prepared in step S5, continue stirring and reacting for 54 h, place it in a 5 kDa dialysis bag, dialyze it with DMSO for 3 days, transfer it to deionized water and continue dialyzing for 3 days, and freeze-dry it to obtain a nanocomposite material;

[0060] This embodiment also provides a nanocomposite material capable of regulating synaptic plasticity, which is prepared according to the above preparation method.

[0061] Example 3

[0062] This embodiment provides a method for preparing a nanocomposite material capable of regulating synaptic plasticity, which specifically comprises the following steps:

[0063] S1. Accurately weigh 2.8 g of 5,6-diaminouracil and place it in a beaker. Add 2.0 g of glycolic acid and mix well. Raise the reaction temperature to 125°C and stir at 130 rpm for 35 min. After the reaction system is cooled to room temperature, add a mixed solution of ethanol and ether in a volume ratio of 1:3 to the reaction system for precipitation. After filtering, collect the precipitate and wash it repeatedly with anhydrous ethanol three times. Take 3.0 g of the precipitate and dissolve it in 20 mL of ethanol aqueous solution (V 乙醇 :V 水 =2:1), add 10wt% NaOH aqueous solution 18mL at a rate of 0.15mL / min, stir at a rate of 130rpm, raise the reaction temperature to 80°C, react for 2h, wait for the reaction system to cool to room temperature, adjust the pH of the reaction system to 2.0 with 1M HCl, filter, collect precipitate 2, wash repeatedly with deionized water three times, and dry to obtain 8-hydroxymethylxanthine;

[0064] S2. Accurately weigh 2.5 g of 8-hydroxymethylxanthine prepared in step S1 and place it in a flask. Add 5.5 mL of triethylamine and mix it slightly. Then, add 62.5 mL of DMF to dissolve the reactant. After flowing nitrogen, add 3.6 g of chloroacetic acid under a nitrogen atmosphere. After mixing evenly, raise the reaction temperature to 50° C. After reacting for 8 h, add 3.8 g of 4-chlorobenzyl bromide and 5.5 g of potassium carbonate. After mixing evenly, raise the reaction temperature to 90° C. After reacting for 2 h, dilute with 500 mL of deionized water, extract with ethyl acetate, take the organic phase and dry it with anhydrous sodium sulfate overnight. Remove the ethyl acetate and purify it to obtain the NMDA antagonist recognition body.

[0065] S3, accurately weigh 2.5g of the NMDA antagonist recognition body prepared in step S2 into a flask, add 50mL of DMF, stir at 150rpm until the reactant is completely dissolved, place in an ice water bath, add 1.7g of DCC and 1.36g of HOBt, continue to stir and mix evenly, add 3.1g of BOC-D-glutamine, stir and react at room temperature at 170rpm, react for 15h, filter, collect the filtrate, add 200mL of deionized water to dilute, extract with ethyl acetate, separate the organic phase, wash with saturated sodium chloride solution, dry with anhydrous sodium sulfate, remove ethyl acetate, and purify to obtain NMDA antagonist recognition body grafted amino acid;

[0066] S4, accurately weigh 0.1 g of the NMDA antagonist recognition body grafted amino acid prepared in step S3, put it into a flask, add it into 40 mL of anhydrous THF, add 25 μL of SOCl2, stir and react at room temperature at a speed of 210 rpm, react for 50 min, filter, collect the precipitate, wash it repeatedly with anhydrous ether three times, and dry it to obtain the NMDA antagonist recognition body grafted amino acid;

[0067] S5. Accurately weigh 0.12 g of the NMDA antagonist recognition body grafted amino acid-NCA prepared in step S4 and place it in a flask, add it to 40 mL of DMF, mix until dissolved, introduce flowing nitrogen, add 30 μL of ethylenediamine as an initiator, raise the reaction temperature to 45°C, react for 52 hours, acidify and precipitate with 1 mol / L HCl solution, filter, collect the precipitate, wash with deionized water until neutral, and dry to obtain the NMDA antagonist recognition body grafted polyamino acid;

[0068] S6. Accurately weigh 0.6 g of PLA, place it in a flask, add 20 mL of chloroform, add 0.06 g of NHS and 0.09 g of EDC•HCl, mix well, introduce flowing nitrogen, stir at 300 rpm under nitrogen atmosphere, perform activation reaction for 4.5 h, accurately weigh 0.45 g of the NMDA antagonist recognition body grafted polyamino acid prepared in step S5, continue stirring and reacting for 50 h, place it in a 5 kDa dialysis bag, dialyze it with DMSO for 3 d, transfer it to deionized water and continue dialyzing for 3 d, and freeze-dry to obtain a nanocomposite material;

[0069] This embodiment also provides a nanocomposite material capable of regulating synaptic plasticity, which is prepared according to the above preparation method.

[0070] Comparative Example 1

[0071] This comparative example provides a nanocomposite material and a preparation method thereof, which differs from Example 1 only in that the preparation method does not include step S2, that is, grafting the 8-hydroxymethylxanthine prepared in step S1 onto polyamino acid, and the remaining components and component contents are the same as those in Example 1.

[0072] Comparative Example 2

[0073] This comparative example provides a nanocomposite material and a preparation method thereof, which is different from Example 1 only in that the nanocomposite material is a composite material of polyamino acid, polylactic acid and memantine, which is mixed in a mass ratio of polyamino acid: polylactic acid: memantine of 0.7:1:0.6.

[0074] Experimental Example 1

[0075] The drug memantine and drug-loaded PLA-PLH were dissolved in DMSO at a ratio of 0.35:1. Subsequently, the mixed solution was slowly added dropwise to ultrapure water at pH=6.5 under stirring. Finally, the drug-loaded nanocomposite was obtained by dialysis and freeze-drying. 5 mg of the drug-loaded nanocomposite was weighed, dissolved in methanol, and the volume was adjusted to 25 mL. The supernatant was obtained by ultrasonic lysis and ultracentrifugation, and the fluorescence intensity was measured by a fluorescence spectrophotometer. The encapsulation efficiency (R E ) and drug loading (R L ):

[0076]

[0077] Where: m1 is the mass of encapsulated drug (mg), m2 is the total mass of drug (mg), and m3 is the mass of carrier (mg).

[0078] Figure 2 The encapsulation efficiency and drug loading of the nanocomposite materials prepared by Examples 1-3 and Comparative Examples 1-2 of the present invention are shown in the figure. As shown in the figure, the drug loading and encapsulation efficiency of the nanocomposite materials prepared by Examples 1-3 and Comparative Examples 1-2 are slightly different.

[0079] Experimental Example 2

[0080] 50 SAMP8 mice were constructed into AD model using RANDBETWEEN random function and divided into 5 groups, namely, Examples 1-3 and Comparative Examples 1-2, 10 mice in each group; 10 SAMR1 mice of the same age were used as the normal group. All mice were gavaged from 6 months of age, and the gavage dose of memantine hydrochloride group was 0.004 g / kg. The normal group and the model group were given an equal volume of pure water, once a day, for 3 consecutive weeks.

[0081] Anesthesia was performed by intraperitoneal injection of 1g / kg compound anesthetic (chloral hydrate: urethane = 1:5, configured as 20% compound anesthetic). After successful anesthesia, the mouse head was fixed on a stereotaxic instrument, and then the head skin was cut open. A dental drill was used to drill a hole in the skull (2.0mm behind the bregma and 1.5mm outside the midline), and the fixed stimulating electrode and recording electrode were inserted so that the stimulating electrode and recording electrode were located in the stratum radiatum of the Schaffer collateral and the hippocampal CA1 region, respectively. All fEPSPs were standardized by testing the stimulation-evoked field excitatory postsynaptic potentials (fEP-SPs) and expressed as a slope percentage.

[0082] Figure 3The figure is a comparison of the hippocampal field potential of mice in the treatment groups of Example 1-3 and Comparative Example 1-2; as shown in the figure, an important factor for the expression of LTP in neurons is the increase in calcium concentration in postsynaptic cells. Calcium ions flow in large quantities through NMDA-type glutamate receptors to induce the generation of LTP, thereby enhancing the efficiency of synaptic transmission. The nanocomposite prepared in Example 1-3 can effectively inhibit the conduction of calcium ions of glutamate receptors, reduce the efficiency of synaptic transmission, weaken the excitatory transmission of synapses, enhance inhibitory synaptic transmission, reduce synaptic overexcitation, and relieve chronic oral pain.

[0083] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the invention.

[0084] The present invention and its implementation methods are described above, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it and design methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing a nanocomposite material capable of regulating synaptic plasticity, characterized in that: The specific steps include: S1. Take 5,6-diaminouracil and put it in a flask. Add glycolic acid and mix well. Raise the reaction temperature to 120-130°C. Stir the reaction at 100-120 rpm. After 30-40 min, cool to room temperature. Use ethanol / ether mixed solution for precipitation. After filtering, take precipitate 1 and add it to ethanol aqueous solution. Add 10 wt% NaOH aqueous solution dropwise at 0.15 mL / min. Stir at 120-150 rpm. Raise the reaction temperature to 80-90°C. After reacting for 2-3 h, cool. Use 1 M HCl to adjust the pH of the reaction system to 1.0-2.

0. Filter and collect precipitate 2. Wash with deionized water. After drying, obtain 8-hydroxymethylxanthine. S2, placing the 8-hydroxymethylxanthine and triethylamine prepared in step S1 in a flask, dissolving them in DMF, introducing flowing nitrogen, adding chloroacetic acid dropwise, raising the reaction temperature to 40-50°C, reacting for 8-10 hours, adding 4-chlorobenzyl bromide and potassium carbonate, raising the reaction temperature to 80-90°C, reacting for 2-3 hours, adding deionized water for dilution, extracting with ethyl acetate, taking the organic phase and drying it with anhydrous sodium sulfate, purifying it, and obtaining the NMDA antagonist recognition body; S3, placing the NMDA antagonist recognition body prepared in step S2 in DMF, stirring until completely dissolved, transferring to an ice water bath, adding DCC and HOBt, mixing evenly, adding BOC-D-glutamine, placing at room temperature, stirring at a speed of 150-180 rpm, reacting for 12-18 hours, filtering, collecting the filtrate, diluting with deionized water, extracting with ethyl acetate, separating the organic phase, washing the organic phase with a saturated sodium chloride solution, drying with anhydrous sodium sulfate, and purifying to obtain the NMDA antagonist recognition body grafted amino acid; S4, placing the NMDA antagonist recognition body grafted amino acid prepared in step S3 in anhydrous THF, adding SOCl2, stirring at room temperature at a speed of 200-220 rpm, reacting for 40-60 minutes, precipitating with anhydrous ether, filtering, collecting the precipitate, washing with anhydrous ether, and drying to obtain NMDA antagonist recognition body grafted amino acid-NCA; S5, placing the NMDA antagonist recognition body grafted amino acid-NCA prepared in step S4 in DMF, introducing flowing nitrogen, adding ethylenediamine, raising the temperature to 40-50°C, reacting for 48-54 hours, acidifying and precipitating with 1 mol / L HCl solution, filtering, collecting the precipitate, and drying to obtain the NMDA antagonist recognition body grafted polyamino acid; S6. Dissolve PLA in chloroform, add NHS and EDC•HCl, mix well, introduce flowing nitrogen, stir at 250-300 rpm under nitrogen atmosphere, react for 4-5 hours, add NMDA antagonist recognition body grafted polyamino acid prepared in step S5, continue stirring and react for 48-54 hours, place in DMSO for dialyzing for 3 days, transfer to deionized water for dialyzing for 3 days, and freeze-dry to obtain a nanocomposite material.

2. The method for preparing a nanocomposite material capable of regulating synaptic plasticity according to claim 1, characterized in that: In step S1, the mass ratio of the 5,6-diaminouracil to glycolic acid is 1.3-1.5:1; the mass concentration of the precipitate 1 in the ethanol aqueous solution is 0.1-0.15 g / mL; the mass volume ratio of the precipitate 1 to the NaOH aqueous solution is 0.15-0.2 g / mL.

3. The method for preparing a nanocomposite material capable of regulating synaptic plasticity according to claim 2, characterized in that: In step S2, the mass volume ratio of the 8-hydroxymethylxanthine to triethylamine is 0.4-0.5 g / mL; the mass concentration of the 8-hydroxymethylxanthine in DMF is 0.03-0.05 g / mL; and the mass ratio of the 8-hydroxymethylxanthine to chloroacetic acid is 0.6-0.8:

1.

4. The method for preparing a nanocomposite material capable of regulating synaptic plasticity according to claim 3, characterized in that: In step S2, the mass ratio of the 4-chlorobenzyl bromide to potassium carbonate is 0.7-0.8:1; the mass ratio of the 8-hydroxymethylxanthine to 4-chlorobenzyl bromide is 0.6-0.7:

1.

5. The method for preparing a nanocomposite material capable of regulating synaptic plasticity according to claim 4, characterized in that: In step S3, the mass concentration of the NMDA antagonist recognition body in DMF is 0.03-0.05 g / mL; the mass ratio of DCC to HOBt is 1:0.7-0.

9.

6. The method for preparing a nanocomposite material capable of regulating synaptic plasticity according to claim 5, characterized in that: In step S3, the mass ratio between the NMDA antagonist recognition body and DCC is 1.3-1.5:1; the mass ratio between the NMDA antagonist recognition body and BOC-D-glutamine is 0.6-0.8:

1.

7. The method for preparing a nanocomposite material capable of regulating synaptic plasticity according to claim 6, characterized in that: In step S4, the mass concentration of the NMDA antagonist receptor grafted amino acid in anhydrous THF is 2-3 mg / mL; the mass volume ratio of the NMDA antagonist receptor grafted amino acid to SOCl2 is 3-5 g / mL.

8. The method for preparing a nanocomposite material capable of regulating synaptic plasticity according to claim 7, characterized in that: In step S5, the mass concentration of the NMDA antagonist recognizer grafted amino acid-NCA in anhydrous DMF is 3-5 mg / mL; the mass volume ratio between the NMDA antagonist recognizer grafted amino acid-NCA and ethylenediamine is 4-5 g / mL.

9. The method for preparing a nanocomposite material capable of regulating synaptic plasticity according to claim 8, characterized in that: In step S6, the mass concentration of PLA in chloroform is 0.02-0.04 g / mL; the added mass of NHS is 10%-12% of the mass of PLA; the added mass of EDC•HCl is 15%-20% of the mass of PLA; and the mass ratio between the NMDA antagonist receptor grafted polyamino acid and PLA is 0.7-0.8:

1.

10. A nanocomposite material capable of regulating synaptic plasticity, characterized in that: Prepared according to the preparation method according to any one of claims 1 to 9.

Images