Lycium barbarum polysaccharide and betaine self-assembled nanoparticles, and a preparation method and application thereof

Abstract

The application discloses a kind of self-assembly nanoparticles of gypenoside and betaine and preparation method and application thereof, belong to medical technical field, the preparation method of self-assembly nanoparticles of gypenoside and betaine includes the following steps: betaine is dissolved in anhydrous ethanol, to obtain organic phase, gypenoside is dissolved in deionized water, to obtain water phase;Under ultrasonic condition, organic phase is slowly dropwise added into water phase, rotary evaporation is removed organic solvent, to obtain the self-assembly nanoparticles of gypenoside and betaine.The self-assembly nanoparticles of gypenoside and betaine has good in vivo and in vitro anti-inflammatory activity, this preparation combined self-assembly nanoparticle mode can achieve the effect of synergistic effect and attenuation, lay a foundation for the anti-inflammatory activity research of medicine and food homology drug, especially gypenoside extracted polysaccharide, provide new strategy for further drug treatment of colitis, have great application prospect.

Description

Technical Field

[0001] The present invention relates to the field of medical technology, in particular to self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine, a preparation method thereof and an application thereof, and more particularly to self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine, a preparation method thereof and an application thereof in a drug for treating ulcerative colitis. Background Art

[0002] Ulcerative colitis (UC) is a chronic, relapsing inflammatory gastrointestinal disease characterized by immune system dysfunction and gastrointestinal inflammation. It causes inflammation and damage to the colonic mucosa, disrupts the gastrointestinal mucosal barrier, and increases the risk of colorectal cancer. Clinical manifestations include abdominal pain, diarrhea, bloody stools, and weight loss. Currently, UC remains incurable, and treatment strategies primarily target the colonic mucosa and reduce systemic inflammation to modulate the exacerbated host immune response. UC patients generally require long-term, uninterrupted drug therapy, and in severe cases, even surgical intervention. The main clinical treatment for this disease is mesalazine (5-ASA), which effectively suppresses intestinal inflammation. However, this drug is associated with a high relapse rate after discontinuation, low patient acceptance, and systemic distribution, which can cause adverse reactions. Furthermore, long-term use of these drugs can impair immunity, making patients more susceptible to infection and disease.

[0003] Lycium barbarum polysaccharides (LBP), derived from the traditional Chinese medicinal and edible plant Lycium barbarum L., are one of the main bioactive components of Lycium barbarum and possess a wide range of biological properties, including anti-inflammatory, immunomodulatory, toxicity-reducing, and intestinal microbiome regulation. Furthermore, combination therapy is considered an effective strategy for the treatment of ulcerative colitis (UC), enhancing immunity and anti-inflammatory effects while reducing adverse drug reactions. Betaine, a zwitterionic quaternary ammonium compound and a methyl derivative of glycine, possesses certain transmethylation, osmotic pressure regulation, anti-inflammatory, antioxidant, and immune functions. Lycium barbarum polysaccharide is an acidic polysaccharide. BET-LBP-1 NPs are formed through self-assembly of the acidic polysaccharide and alkaloids. Combining these two drugs can promote the treatment of inflammation.

[0004] Therefore, how to develop a self-assembled nanoparticle of Lycium barbarum polysaccharide and betaine, a preparation method thereof, and its application in the treatment of ulcerative colitis are technical problems that need to be solved urgently by those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a self-assembled nanoparticle of Lycium barbarum polysaccharide and betaine, a preparation method thereof, and application thereof in a drug for treating ulcerative colitis.

[0006] To achieve the above object, the present application adopts the following technical solutions:

[0007] A preparation method of a wolfberry polysaccharide and betaine self-assembled nanoparticle, comprising the following steps:

[0008] (1) dissolving betaine in anhydrous ethanol to obtain an organic phase, and dissolving wolfberry polysaccharide in deionized water to obtain an aqueous phase;

[0009] (2) slowly and dropwise adding the organic phase into the aqueous phase under ultrasonic conditions, and removing the organic solvent by rotary evaporation to obtain the above-mentioned wolfberry polysaccharide and betaine self-assembled nanoparticle.

[0010] The present application has the following beneficial effects: Wolfberry polysaccharide is an acidic polysaccharide, which is self-assembled with alkaloids to form BET-LBP-1NPs, and the combination of the two drugs can promote the treatment of inflammation to a certain extent. In the present application, betaine (BET) and wolfberry polysaccharide (LBP), which is an effective component extracted from wolfberry, are self-assembled into nanoparticles by ultrasonic drop infusion to construct a wolfberry polysaccharide betaine self-assembled nanoparticle. The anti-inflammatory activity of the self-assembled nanoparticle in vivo is studied by oral administration to ulcerative colitis mice, and the drug efficacy of the self-assembled nanoparticle is compared with that of mesalazine (5-ASA). The experimental results show that BET / LBP-1NPs have good anti-inflammatory activity in vitro and in vivo. This preparation method of the self-assembled nanoparticle can achieve the effect of synergistic efficacy and reduced toxicity, and lays a foundation for the anti-inflammatory activity research of food-medicine homologous drugs, especially wolfberry polysaccharide. It provides a new strategy for further drug treatment of colitis, and has great application prospect.

[0011] Further, in step (1), the mass-volume ratio of betaine, wolfberry polysaccharide, anhydrous ethanol and deionized water is (20-60) mg:(10-30) mg:(1-2) mL:5 mL.

[0012] The beneficial effects of the above further technical solutions are: when the ratio of betaine to wolfberry polysaccharide is 2:1, the preparation effect is the best, the prepared nanoparticles have uniform and small particle size, and can better increase the oral absorption and utilization.

[0013] Further, in step (2), the ultrasonic power is 25 w.

[0014] Further, in step (2), the organic phase is slowly and dropwise added into the aqueous phase at a dropwise adding speed of 2 drops / s.

[0015] Further, in step (2), the rotary evaporation temperature is 45℃, the rotary evaporation pressure is 90 bar, and the rotary evaporation time is 3-5 minutes.

[0016] The present invention also provides self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine prepared by the above method.

[0017] The present invention also provides an application of the above-mentioned Lycium barbarum polysaccharide and betaine self-assembled nanoparticles in a medicine for treating ulcerative colitis. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Daily body weight changes of mice in each group;

[0019] Figure 2 Disease activity index (DAI) of mice in each group;

[0020] Figure 3 Evaluation of colon pathological changes in each group (compared with the Model group, *P < 0.05; compared with the normal group, #P < 0.05);

[0021] Figure 4 Colon anatomy images and colon length of each group (compared with the Model group, *P < 0.05; compared with the Blank group, #P < 0.05);

[0022] Figure 5 HE staining of colon pathological sections in each group;

[0023] Figure 6 In the figure, a is the cytokine IL-6 Elisa detection result in the tissues of each group (n=6); b is the cytokine IL-6 Elisa detection result in the serum of each group (n=6); c is the cytokine IL-10 Elisa detection result in the tissues of each group (n=6); d is the cytokine IL-10 Elisa detection result in the serum of each group (n=6); e is the cytokine IFN-γ Elisa detection result in the tissues of each group (n=6); f is the cytokine IFN-γ Elisa detection result in the serum of each group (n=6); (compared with the Model group, *P<0.05). DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] The method for extracting Lycium barbarum polysaccharides in the embodiments and comparative examples of the present invention (see Chinese patent application number: 202410863239.5) comprises the following steps:

[0026] (1) 500 g of wolfberry was crushed and defatted with 95% ethanol, dried and weighed; extracted with 100°C hot water in a decoction pot at a material-liquid ratio of 1:10 for 2 h, and the extraction was repeated three times. The filtrate was filtered through gauze, the filtrate was combined, concentrated under reduced pressure, and precipitated with 3 times the volume of 95% ethanol, dried and weighed to obtain crude LBP polysaccharide;

[0027] (2) The crude LBP polysaccharide solution prepared in step (1) was repeatedly subjected to the Sevag reagent (V chloroform: V n-butanol = 4:1) to remove protein until the white middle layer disappeared; the supernatant was collected, concentrated, and freeze-dried to obtain deproteinized LBP; the deproteinized LBP solution was depigmented using D101 macroporous adsorption resin, and the eluate was then concentrated by rotary evaporation and freeze-dried to obtain decolorized LBP;

[0028] (3) Weigh 100 mg of the decolorized LBP prepared in step (2) and dissolve it in 10 mL of distilled water. After it is fully dissolved, centrifuge at 5000 r / min for 10 min to obtain the supernatant; chromatograph on a DEAE-52 cellulose column (Φ2.6×50 cm), and elute with distilled water, 0.1 mol / L NaCl, 0.2 mol / L NaCl, and 0.5 mol / L NaCl in sequence to obtain LBP-1, LBP-2, LBP-3, and LBP-4, respectively. The elution flow rate is 2 mL / min, and 10 mL is collected in each tube; the eluate is collected and detected by the phenol-sulfuric acid method in separate tubes, and an elution curve is drawn with the tube number as the horizontal axis and the absorbance value as the vertical axis; based on the elution curve, the eluates of the same elution peak are combined, concentrated under reduced pressure, and freeze-dried to obtain four refined LBPs of different molecular weights, and LBP-1 with a relative molecular mass of 2726 is used for subsequent preparation.

[0029] Example 1

[0030] The preparation method of self-assembled nanoparticles of wolfberry polysaccharide and betaine comprises the following steps:

[0031] (1) Dissolve 20 mg of betaine in 1 mL of anhydrous ethanol to obtain an organic phase, and dissolve 10 mg of Lycium barbarum polysaccharide in 5 mL of deionized water to obtain an aqueous phase;

[0032] (2) Under ultrasonic conditions with an ultrasonic power of 25 W, the organic phase was slowly added dropwise into the aqueous phase at a dropping speed of 2 drops / s. The organic solvent was removed by rotary evaporation at a rotary evaporation temperature of 45 ° C, a rotary evaporation pressure of 90 bar, and a rotary evaporation time of 3 minutes to obtain a solution of self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine, which was recorded as BET / LBP-1NPs.

[0033] Example 2

[0034] The preparation method of self-assembled nanoparticles of wolfberry polysaccharide and betaine comprises the following steps:

[0035] (1) Dissolve 40 mg of betaine in 1.5 mL of anhydrous ethanol to obtain an organic phase, and dissolve 20 mg of Lycium barbarum polysaccharide in 5 mL of deionized water to obtain an aqueous phase;

[0036] (2) Under ultrasonic conditions with an ultrasonic power of 25 W, the organic phase was slowly added dropwise into the aqueous phase at a dropping speed of 2 drops / s, and the organic solvent was removed by rotary evaporation at a rotary evaporation temperature of 45 ° C, a rotary evaporation pressure of 90 bar, and a rotary evaporation time of 4 minutes to obtain a solution of self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine.

[0037] Example 3

[0038] The preparation method of self-assembled nanoparticles of wolfberry polysaccharide and betaine comprises the following steps:

[0039] (1) Dissolve 60 mg of betaine in 2 mL of anhydrous ethanol to obtain an organic phase, and dissolve 30 mg of Lycium barbarum polysaccharide in 5 mL of deionized water to obtain an aqueous phase;

[0040] (2) Under ultrasonic conditions with an ultrasonic power of 25 W, the organic phase was slowly added dropwise into the aqueous phase at a dropping speed of 2 drops / s, and the organic solvent was removed by rotary evaporation at a rotary evaporation temperature of 45 ° C, a rotary evaporation pressure of 90 bar, and a rotary evaporation time of 5 minutes to obtain a solution of self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine.

[0041] Comparative Example 1

[0042] The preparation method of self-assembled nanoparticles of wolfberry polysaccharide and betaine comprises the following steps:

[0043] (1) Dissolve 10 mg of betaine in 1 mL of anhydrous ethanol to obtain an organic phase, and dissolve 10 mg of Lycium barbarum polysaccharide in 5 mL of deionized water to obtain an aqueous phase;

[0044] (2) Under ultrasonic conditions with an ultrasonic power of 25 W, the organic phase was slowly added dropwise into the aqueous phase at a dropping speed of 2 drops / s, and the organic solvent was removed by rotary evaporation at a rotary evaporation temperature of 45 ° C, a rotary evaporation pressure of 90 bar, and a rotary evaporation time of 5 minutes to obtain a solution of self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine.

[0045] Comparative Example 2

[0046] The preparation method of self-assembled nanoparticles of wolfberry polysaccharide and betaine comprises the following steps:

[0047] (1) Dissolve 40 mg of betaine in 1.5 mL of anhydrous ethanol to obtain an organic phase, and dissolve 10 mg of Lycium barbarum polysaccharide in 5 mL of deionized water to obtain an aqueous phase;

[0048] (2) Under ultrasonic conditions with an ultrasonic power of 25 W, the organic phase was slowly added dropwise into the aqueous phase at a dropping speed of 2 drops / s, and the organic solvent was removed by rotary evaporation at a rotary evaporation temperature of 45 ° C, a rotary evaporation pressure of 90 bar, and a rotary evaporation time of 5 minutes to obtain a solution of self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine.

[0049] Comparative Example 1

[0050] The preparation method of the physical mixture group (BET+LBP-1) comprises the following steps:

[0051] (1) 20 mg of betaine and 10 mg of Lycium barbarum polysaccharide (LBP-1) were mixed to obtain a physical mixture group, which was recorded as BET+LBP-1.

[0052] Effect Experiment

[0053] 1. Basic representation

[0054] The particle size, polydispersity index (PDI) and zeta potential of the self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine in Example 1, Comparative Example 1 and Comparative Example 2 were measured using a ZetasizerNano ZS Malvern particle size potential analyzer, and the measurement was repeated three times for each sample.

[0055] Table 1 Changes in nanoparticle size at different drug ratios

[0056] LBP-1:BET LBP-1:BET Particle size (nm) PDI Zeta(mV) Comparative Example 1 1:1 310.9±9.496 0.319±0.036 -16.0±3.51 Example 1 1:2 171.2±10.78 0.239±0.036 -14.5±1.91 Comparative Example 2 1:4 400.7±33.42 0.530±0.050 -11.8±2.33

[0057] As shown in Table 1, when LBP-1:BET=1:2, the particle size and PDI are the smallest, indicating that the nanoparticles formed at this dosage are stable and uniform, with a small particle size, can be more aggregated to the diseased site in the body, have better bioavailability and exert anti-inflammatory effects.

[0058] 2. Determination of drug loading capacity of BET / LBP-1 NPs

[0059] 1 mL of the nanoparticle solution of Example 1 was freeze-dried (pre-freezing temperature -20°C, main drying temperature 20°C, vacuum 0.370 mbar, final drying temperature 30°C, vacuum 0.05 bar, drying time 48 h). The weight of the freeze-dried powder was accurately weighed as W. The freeze-dried powder was dissolved in 10 volumes of chromatographic methanol, vortexed, and centrifuged at 13000 rpm for 30 min. The supernatant was analyzed by HPLC and substituted into the standard curve y = 0.062x + 0.5742 (R 2 =0.9994) to obtain the betaine content C in 1 mL of nanoparticle solution. The drug loading capacity (DLC) was calculated according to the following formula.

[0060]

[0061] The drug loading of BET / LBP-1 NPs was 22.53% measured by HPLC method.

[0062] As can be seen from the above, the drug loading of BET / LBP-1 NPs is 22.53%, which improves the solubility of the monomer, indicating that the drug is successfully loaded and facilitates subsequent drug administration.

[0063] 3. Animal experiment design

[0064] Seventy mice were acclimated for one week and randomly divided into 7 groups, 10 mice in each group: normal control group (Blank), model control group (Model), positive drug mesalazine group (150 mg / kg) (5-ASA), lycium barbarum polysaccharide group (LBP-1), betaine group (BET), comparative example 1 physical mixture group (BET+LBP-1), example 1 lycium barbarum polysaccharide and betaine self-assembled nanoparticle group (BET / LBP-1 NPs);

[0065] One day before the experiment, the mice in each group were fasted for 12 hours without water, and during the experiment, all mice were given standard feed, with a daily gavage volume of 1 mL / 100 g, and continuous administration for 13 days. On the 14th day, samples were taken from each group for related index detection;

[0066] Among them, the mice in the Blank group were given sterile water during the experiment and drank freely;

[0067] The Model group was given sterile water containing 4% dextran sulfate sodium (DSS) and drank freely for 7 consecutive days to induce the establishment of an ulcerative colitis model. After the model was successfully established, the mice were first given normal water to drink freely for 3 days, and then given 3.5% DSS to continue to drink freely.

[0068] The LBP-1 group, the BET group, the BET+LBP-1 group, and the BET / LBP-1 NPs group were given sterile water containing 4% dextran sulfate sodium (DSS) and drank freely for 7 consecutive days to induce the establishment of an ulcerative colitis model. After the model was successfully established, the mice were first given normal water to drink freely for 3 days, and then given 3.5% DSS to continue to drink freely. At the same time, daily gavage administration was performed, with a dosage of 300 mg / kg.

[0069] The 5-ASA group was given water containing 4 wt% dextran sulfate sodium (DSS) and drank freely for 7 consecutive days to induce the establishment of an ulcerative colitis model. After the model was successfully established, the mice were first given normal water to drink for 3 days, and then given 3.5% DSS to continue to drink. Daily gavage administration was performed, with a dosage of 150 mg / kg.

[0070] 3.1 Disease activity index score (DAI score)

[0071] The body weight of each mouse group was recorded daily. The mice's mental state, physical signs, and bowel movements were observed twice daily. The mice's mental state, stool consistency, hair smoothness, glossiness, perianal lesions, and fecal occult blood were also observed and recorded. The Disease Activity Index (DAI) scoring criteria are shown in Table 1: DAI = (weight loss score + stool consistency score + blood in stool score) / 3.

[0072] Table 2 DAI scoring criteria

[0073]

[0074]

[0075] like Figure 1 As shown, the weight of mice in the Model group showed the most obvious downward trend. As time went on, the weight of the Model group and the 5-ASA group continued to decrease, while the weight of the drug-treated group showed an upward trend. On the 14th day, the weight of mice in the Model group was significantly reduced compared with the Blank group (P<0.01); compared with the Model group, there were statistical differences in the 5-ASA group and each experimental group (P<0.05); the weight of the BET / LBP-1NPs group was more uniform, which was greatly improved compared with the Model. There was no significant change in the general signs of the Blank group mice, such as body weight and hair, and no deaths; there were deaths in both the Model group and the BET group mice. As shown Figure 2 As shown, the DAI scores of mice in the Model group increased compared with the Blank group (P<0.05); compared with the Model group, the DAI scores of mice in the 5-ASA group, LBP-1 group, LBP-1+BET group, and BET / LBP-1NPs group decreased (P<0.05). Among them, the BET / LBP-1NPs group showed significant improvements in stool shape and bloody stool compared with the Model group. In summary, LBP-1 may be the main component that exerts anti-inflammatory effects and improves the weight loss of colitis mice. The BET / LBP-1NPs group is superior to the 5-ASA group to a certain extent, and there is no significant statistical difference between it and the BET+LBP-1 group. However, it can inhibit the aggravation of inflammation and weight loss earlier because the smaller particle size of the nanoparticles can promote the passive transport and absorption of the drug.

[0076] 3.2 Macroscopic observation of colon tissue and evaluation of pathological changes

[0077] On the 14th day of the experiment, mice in each group were killed by cervical dislocation, and the entire colon was quickly dissected out. The colon length of each group of mice was measured with a ruler. The colon was opened longitudinally along the mesentery, rinsed several times with pre-cooled saline, and dried with filter paper. The colon was visually observed and scored for colonic mucosal inflammation and ulceration according to the criteria listed in Table 3.

[0078] Table 3 Macroscopic observation and pathological scoring criteria of colon tissue

[0079]

[0080]

[0081] like Figure 3 The colon lesion scores of mice in the Model group increased compared to those in the Blank group (P<0.01). Compared with the Model group, the lesion scores of all experimental groups decreased, with the BET / LBP-1 NPs group showing a more significant decrease (P<0.05). These results suggest that the combination of LBP-1 and BET has a certain alleviating effect on colonic intestinal damage in mice.

[0082] 3.3 Colon length measurement and tissue preservation

[0083] After the experiment, blood was collected from the mouse's orbital capillaries, and the colon was dissected. Colon length was measured, and the blood was centrifuged to obtain the supernatant for serum. A portion of the colon tissue was fixed in 4% paraformaldehyde for H&E staining. The remaining colon tissue was ground with tissue grinding beads and centrifuged (12,000 rpm for 10 minutes). The supernatant and serum were then used together for subsequent ELISA analysis.

[0084] like Figure 4 As shown in the data, compared with the Blank group, the colon length of the mice in the Model group was significantly shortened (P<0.05); compared with the Model group, the colon length of the mice in the 5-ASA group and the LBP-1 group increased slightly, the increase in the BET group was not obvious, and the colon length of the BET+LBP-1 group and the BET / LBP-1NPs group increased (P<0.05). The colon length of the BET / LBP-1NPs group was closest to that of the Blank group and was significantly better than that of the 5-ASA group.

[0085] 3.4 H&E staining and histopathological examination of colon tissue

[0086] The fixed colon tissue was dehydrated and embedded in paraffin, and 4 μm paraffin sections were prepared. After dewaxing and hydration, HE staining was performed, and the sections were observed and photographed using an optical biological microscope for colon tissue pathology analysis.

[0087] Depend on Figure 5Analysis revealed that the mucosal epithelium in the Blank group had a neat, orderly arrangement, with no degeneration or shedding. Crypts were clearly structured, glands were orderly arranged, and their number did not decrease. Glandular epithelial cells showed no changes. Inflammatory cells were scattered throughout the interstitium, but there was no congestion, hemorrhage, or edema. In the Model group, large areas of mucosal epithelial cells shed, ulcers enlarged, and fused. Crypts were severely damaged and their structure was unclear. Glands degenerated and necrotic, with a significant decrease in number. Large areas of inflammatory cell infiltration throughout the intestinal wall were present, with significant congestion and edema, and localized abscess formation, indicating successful colitis modeling. Compared with the Model group, the 5-ASA, LBP-1, BET+LBP-1, and BET / LBP-1NPs groups showed less mucosal epithelial shedding and smaller ulcers. Crypts were mildly to moderately damaged, with visible structure. Glands showed degeneration, decreased necrosis, and a mild decrease in number. Varying amounts of inflammatory cells infiltrated throughout the intestinal wall, with mild congestion and edema, and focal abscess formation. Compared with the other groups, the BET / LBP-1 NPs group showed smaller mucosal ulcers, mild crypt destruction, less glandular degeneration, and a less pronounced decrease in glandular number. Submucosal infiltration of inflammatory cells was also observed, and submucosal edema remained significant. This suggests that BET / LBP-1 self-assembled nanoparticles have a significant therapeutic effect on ulcerative colitis.

[0088] 3.5 ELISA analysis of inflammatory cytokine expression in colon tissue and serum

[0089] After the colon tissue was homogenized in PBS containing protease inhibitors, IL-6, IL-10, IFN-γ, NO, and reactive oxygen species were detected according to the recommended procedures of the ELISA kit, and the OD values ​​were read at a wavelength of 450 nm.

[0090] like Figure 6 As shown in the results, compared with the Blank group, the expression levels of IL-6 and IFN-γ in the colon tissues of mice in the Model group were significantly increased (P < 0.05), while the expression level of IL-10 was significantly decreased (P < 0.05). Compared with the Model group, the expression levels of IL-6 and IFN-γ in the colon tissues of mice in the 5-ASA group and all experimental groups were decreased (P < 0.05), while the expression level of IL-10 was increased (P < 0.05). Among the serum cytokines, only the LBP-1 group had a significant decrease in IL-6 expression (P < 0.05). These results indicate that BET and LBP-1 primarily reduce the expression levels of the pro-inflammatory cytokines IL-6 and IFN-γ and increase the expression level of the anti-inflammatory cytokine IL-10 through LBP-1, thereby achieving the therapeutic effect of colitis. BET itself has no significant anti-inflammatory effect, but binding to LBP-1 can enhance the anti-inflammatory effect to a certain extent.

[0091] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine, characterized in that: The steps include: (1) Betaine was dissolved in anhydrous ethanol to obtain an organic phase, and Lycium barbarum polysaccharide was dissolved in deionized water to obtain an aqueous phase. The mass ratio of betaine to Lycium barbarum polysaccharide was 2:

1. (2) slowly dripping the organic phase into the aqueous phase drop by drop under ultrasonic conditions, and removing the organic solvent by rotary evaporation to obtain the Lycium barbarum polysaccharide and betaine self-assembled nanoparticles; The preparation method of Lycium barbarum polysaccharide comprises the following steps: (a) 500 g of wolfberry was crushed and defatted with 95% ethanol, dried and weighed. Extraction was performed in a decoction pot with hot water at 100°C for 2 h at a material-to-liquid ratio of 1:

10. The extraction was repeated three times, filtered through gauze, and the filtrates were combined and concentrated under reduced pressure. The mixture was precipitated with 3 times the volume of 95% ethanol, dried and weighed to obtain crude LBP polysaccharide. (b) The crude LBP polysaccharide solution prepared in step (a) was treated with Sevag reagent (V chloroform:V n-butanol = 4:1) to remove protein, and the operation was repeated several times until the white middle layer disappeared; The supernatant was collected, concentrated, and freeze-dried to obtain deproteinized LBP; the deproteinized LBP solution was depigmented using D101 macroporous adsorption resin, and the eluate was then concentrated by rotary evaporation and freeze-dried to obtain decolorized LBP; (c) Weigh 100 mg of the decolorized LBP prepared in step (b) and dissolve it in 10 mL of distilled water. After complete dissolution, centrifuge at 5000 rpm for 10 min and collect the supernatant. LBP-1, LBP-2, LBP-3, and LBP-4 were obtained by chromatography on a Φ2.6 × 50 cm DEAE-52 cellulose column, eluted with distilled water, 0.1 mol / L NaCl, 0.2 mol / L NaCl, and 0.5 mol / L NaCl, respectively. The elution rate was 2 mL / min, and 10 mL was collected in each tube. The eluate was collected and detected by the phenol-sulfuric acid method in separate tubes. The elution curve was plotted with the tube number as the horizontal axis and the absorbance as the vertical axis. According to the elution curve, the eluates of the same elution peak were combined, concentrated under reduced pressure, and freeze-dried to obtain four refined LBPs with different molecular weights. LBP-1 with a relative molecular mass of 2726 was used for subsequent preparation.

2. The method for preparing self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine according to claim 1, characterized in that: In step (2), the ultrasonic power is 25W.

3. The method for preparing self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine according to claim 1, characterized in that: In step (2), the organic phase is slowly added drop by drop into the aqueous phase at a dropping rate of 2 drops / s.

4. The method for preparing self-assembled nanoparticles of Lycium barbarum polysaccharide and betaine according to claim 1, characterized in that: In step (2), the rotary evaporation temperature is 45° C., the rotary evaporation pressure is 90 bar, and the rotary evaporation time is 3-5 minutes.

5. Lycium barbarum polysaccharide and betaine self-assembled nanoparticles prepared by the method according to any one of claims 1 to 4.

6. Use of the Lycium barbarum polysaccharide and betaine self-assembled nanoparticles according to claim 5 in the preparation of a drug for treating ulcerative colitis.

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