Application of Lactobacillus rhamnosus LXW-1 and / or its metabolites in the preparation of products for preventing and / or treating ulcerative colitis

Abstract

The present invention belongs to the field of microbial technology, and specifically relates to an application of Lactobacillus rhamnosus LXW‑1 and / or its metabolites in the preparation of products for preventing and / or treating ulcerative colitis. The present invention obtains a strain of Lactobacillus rhamnosus LXW‑1 by screening, and the Lactobacillus rhamnosus LXW‑1 is deposited in the China Center for Type Culture Collection on May 20, 2024, with a deposit address of: Wuhan, China, Wuhan University, a deposit number of: CCTCC NO: M 20241017, and a classification name of: Lactobacillus rhamnosus LXW‑1. The research results of the present invention show that the metabolites of Lactobacillus rhamnosus LXW‑1 significantly inhibit the inflammatory factors IL‑1β and IL‑6 at ≥1.0 mg / mL. Animal experiments have confirmed that the metabolite reduces DSS-induced ulcerative colitis, improves intestinal lesions, reduces the level of inflammatory factors, enhances intestinal cell connections, and shows good prevention and treatment potential.

Description

Technical Field

[0001] The present invention belongs to the technical field of microorganisms, and specifically relates to an application of Lactobacillus rhamnosus LXW-1 and / or its metabolites in preparing products for preventing and / or treating ulcerative colitis, especially in medicines and feeds. Background Art

[0002] Ulcerative colitis is an intestinal disease with superficial, non-specific lesions in the rectum and colon, the etiology of which is not yet fully understood. It is often accompanied by clinical symptoms such as abdominal pain, fever, vomiting, diarrhea, rectal blood in the stool, anemia and weight loss. At present, ulcerative colitis is mostly controlled clinically with Western medicine, but Western medicine treatment has certain side effects and is relatively expensive.

[0003] In recent years, with the in-depth research on ulcerative colitis, it was found that the natural active ingredients contained in plants such as Rhizoma Cyperi and Fructus Sophorae Fructus all showed certain inhibitory activity on ulcerative colitis, becoming a research hotspot for the prevention or treatment of ulcerative colitis.

[0004] "All medicines are poisonous to some extent." For example, although Xihuangcao has certain effects of clearing away heat and detoxifying, taking Xihuangcao for a long time will produce certain side effects. At present, the serious adverse symptoms caused by Xihuangcao are still unknown. In addition, if Xihuangcao is taken improperly, it will increase the burden on the liver and aggravate the condition. It can be seen that the active ingredients contained in natural plant extracts are complex. During long-term use, whether it will cause certain damage or inhibitory effects on other normal cells of the body, and these problems will not be exposed in a short time. In other words, there are great safety risks in applying Chinese medicine extracts to ulcerative colitis.

[0005] Therefore, a more in-depth study of the pathogenesis of ulcerative colitis and the provision of a safer and more effective product based on this will be of great significance in solving the problems of ulcerative colitis in the future. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a use of Lactobacillus rhamnosus LXW-1 and / or its metabolites in the preparation of a product for preventing and / or treating ulcerative colitis.

[0007] In the first aspect, the present invention provides a Lactobacillus rhamnosus LXW-1, which was deposited in the China Center for Type Culture Collection (address: Wuhan University, Wuhan, China) on May 20, 2024, with a deposit number of CCTCC NO: M 20241017, and a classification name of Lactobacillus rhamnosus LXW-1 Lactobacillus rhamnosus LXW-1.

[0008] In a second aspect, the present invention provides a product containing the Lactobacillus rhamnosus LXW-1 and / or its metabolites described in the first aspect.

[0009] In a third aspect, the present invention provides a use of the Lactobacillus rhamnosus LXW-1 and / or its metabolites described in the first aspect in the preparation of a product for preventing and / or treating ulcerative colitis.

[0010] The above-mentioned Lactobacillus rhamnosus LXW-1 and / or its metabolites are used as active ingredients of products for preventing and / or treating ulcerative colitis in the application of the above-mentioned products (including but not limited to medicines and feeds); of course, the above-mentioned products may also contain active ingredients with other functions.

[0011] Preferably, the effect is ideal when the content of the metabolite of Lactobacillus rhamnosus LXW-1 in the above-mentioned medicine or feed is 0.25-2.0 mg / mL, preferably 1.0 mg / mL. The medicine or feed may also include an excipient, which is selected from at least one of a binder, a filler, a disintegrant, a lubricant, a preservative, an antioxidant, a flavoring agent, a fragrance, an emulsifier, a colorant, and a solubilizer.

[0012] Preferably, the preparation method of the metabolite of Lactobacillus rhamnosus LXW-1 is as follows:

[0013] S1. Cultivate Lactobacillus rhamnosus LXW-1 in MRS medium for 12-48 h to obtain culture metabolites;

[0014] S2. centrifuging the culture metabolites obtained in S1 using a centrifugal device to recover the culture supernatant and the biomass precipitate respectively;

[0015] S3. Add 0.1-0.2 M alkaline solution to the biomass precipitate recovered in S2, stir for 20-30 min, centrifuge using a centrifuge, and collect the cell lysis supernatant;

[0016] S4. The culture supernatant obtained in S2 and the cell lysis supernatant obtained in S3 are combined, and citric acid and dry matter are added to obtain the metabolites of Lactobacillus rhamnosus LXW-1.

[0017] Preferably, the dry matter is selected from one or two of maltodextrin and cyclodextrin; the weight ratio of citric acid to dry matter is 1:10-20, and the sum of the weight of citric acid and dry matter accounts for 5-10% of the combined liquid weight.

[0018] Preferably, the metabolites of Lactobacillus rhamnosus LXW-1 act by improving at least one of the levels of inflammatory factors, tight junction proteins, and the abundance and diversity of intestinal flora in subjects (such as mice) with ulcerative colitis.

[0019] More preferably, the metabolites of Lactobacillus rhamnosus LXW-1 act by improving the levels of inflammatory factors and tight junction proteins in at least one cell line of HT-29, Caco-2, COLO320DM, DLD-1, and LS513.

[0020] Preferably, the inflammatory factor is selected from at least one of IL-1β, IL-6, IL-8, IL-10, TGF-β, and TNF-α.

[0021] Preferably, the tight junction protein is selected from at least one of Occludin, Claudins, JAM-1, JAM-4 and ZO-1.

[0022] The beneficial effects of the present invention are:

[0023] The present invention provides a Lactobacillus rhamnosus LXW-1 and / or its metabolites that can be applied to ulcerative colitis. Experiments in the present invention show that the metabolites obtained by fermenting the above-mentioned Lactobacillus rhamnosus LXW-1 can alleviate ulcerative colitis to a certain extent, and the substrate cost required for microbial fermentation is low, the raw materials are easy to obtain, and the metabolites obtained after fermentation are highly specific. More specifically, the preferred embodiments of the present invention have the following advantages:

[0024] (1) By constructing an LPS-induced inflammatory cell model, the inhibitory effect of the metabolites of Lactobacillus rhamnosus LXW-1 on cell inflammation was studied. The results showed that when the concentration of the metabolites of Lactobacillus rhamnosus LXW-1 reached above 1.0 mg / mL, the concentrations of inflammatory factors IL-1β and IL-6 in the cell supernatant gradually decreased, showing a significant anti-inflammatory effect.

[0025] (2) The expression of tight junction proteins was detected by Western blotting, which proved that the metabolites of Lactobacillus rhamnosus LXW-1 significantly promoted the expression of actin β-actin, cell junction protein Occludin and ZO-1, and could enhance the tight junction level of tissue cells; it also further proved that the metabolites of Lactobacillus rhamnosus LXW-1 had the effect of inhibiting inflammatory factors;

[0026] (3) A mouse model of enteritis was established, and the metabolites of Lactobacillus rhamnosus LXW-1 of the present invention were gavaged to the mice. The experimental results showed that the metabolites of Lactobacillus rhamnosus LXW-1 of the present invention could alleviate DSS-induced ulcerative colitis in mice; tissue staining results showed that the 0.2 g / kg and 0.4 g / kg administration groups (metabolites of Lactobacillus rhamnosus LXW-1) of the present invention had a significant improvement effect on ulcerative colitis in mice. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a microscopic morphological picture of the colony of Lactobacillus rhamnosus LXW-1 screened and obtained in Example 1 of the present invention;

[0028] Figure 2 The effect of different addition concentrations of the metabolites of Lactobacillus rhamnosus LXW-1 in Example 2 of the present invention on the growth of human cloned colon adenocarcinoma cell Caco-2;

[0029] Figure 3 The inflammatory factor IL-1β in the cell supernatant in Example 3 of the present invention changes with the concentration of the metabolite sample of Lactobacillus rhamnosus LXW-1;

[0030] Figure 4 The inflammatory factor IL-6 in the cell supernatant in Example 3 of the present invention changes with the concentration of the metabolite sample of Lactobacillus rhamnosus LXW-1;

[0031] Figure 5 This is the significance analysis of IL-1β mRNA under different concentrations and action times of the metabolite samples of Lactobacillus rhamnosus LXW-1 in Example 3 of the present invention;

[0032] Figure 6 This is the significance analysis of IL-6 mRNA under different concentrations and action times of the metabolite samples of Lactobacillus rhamnosus LXW-1 in Example 3 of the present invention;

[0033] Figure 7 The staining results of actin β-actin, cell junction protein Occludin and ZO-1 by Western Blot method in Example 4 of the present invention are as follows;

[0034] Figure 8 The expression of the metabolites of Lactobacillus rhamnosus LXW-1 on the related proteins in Example 4 of the present invention;

[0035] Fig. 9 This is the case where the enteritis mouse model was confirmed using body weight in Example 5 of the present invention;

[0036] Fig.10 The change in body weight of mice in the enteritis mouse model established by the DSS induction method in Example 5 of the present invention for 20 days;

[0037] Fig.11 The change of the disease index (DAI) of enteritis mice over time under different treatment conditions in Example 5 of the present invention;

[0038] Fig.12 The intestinal tissue length of the DSS group of the enteritis model under different treatment conditions in Example 5 of the present invention;

[0039] Fig.13 The comparative differences in intestinal tissue length of the DSS group of the enteritis model under different treatment conditions in Example 5 of the present invention;

[0040] Fig.14 This is a case section of colon tissue of enteritis model mice under different treatment conditions in Example 5 of the present invention;

[0041] Fig.15 This is a histological scoring diagram of enteritis model mice under different treatment conditions in Example 5 of the present invention;

[0042] Fig.16 This is a graph showing the results of measuring the level of inflammatory factor IL-1β in the intestinal tissue of mice in Example 5 of the present invention;

[0043] Fig.17 This is a graph showing the results of measuring the level of inflammatory factor IL-6 in the intestinal tissue of mice in Example 5 of the present invention;

[0044] Figures 18A-18D This is a diagram showing the effect of the metabolites of Lactobacillus rhamnosus LXW-1 on reducing the levels of inflammatory factors detected by ELISA and RT-PCR in Example 5 of the present invention. DETAILED DESCRIPTION

[0045] Unless otherwise specified, the experimental materials and reagents used are consumables and reagents that can be obtained from conventional commercial channels.

[0046] Example 1 Screening of bacterial strains

[0047] The lactic acid bacteria selected in the present invention are identified as Lactobacillus rhamnosus by 16S rDNA sequence comparison, numbered as LXW-1, and deposited in the China Center for Type Culture Collection on May 20, 2024, with a deposit number of CCTCC NO: M 20241017, and classified as: Lactobacillus rhamnosus LXW-1 Lactobacillus rhamnosus LXW-1, whose colony and microscopic morphology are as follows Figure 1 shown.

[0048] The metabolites of the above-mentioned Lactobacillus rhamnosus LXW-1 were cultured according to the following steps:

[0049] S1. In MRS medium, Lactobacillus rhamnosus LXW-1 was cultured at 42°C for 48 hours to obtain culture metabolites; wherein the components of MRS medium are: peptone 10 g / L, beef extract powder 5 g / L, yeast extract powder 4 g / L, glucose 2 g / L, Tween-80 1.08 g / L, anhydrous dipotassium hydrogen phosphate 2 g / L, anhydrous sodium acetate 5 g / L, anhydrous triammonium citrate / anhydrous diammonium hydrogen citrate 2 g / L, anhydrous magnesium sulfate 0.2 g / L, monohydrated manganese sulfate 0.05 g / L, cysteine ​​0.5 g / L, lactose 20 g / L;

[0050] S2. Take the culture metabolites obtained in S1, centrifuge at 10000 rpm for 10 min, and obtain the culture supernatant and biomass precipitate;

[0051] S3. Add 0.15 M sodium hydroxide solution to the biomass precipitate in S2, stir for 30 min, centrifuge at 10000 rpm for 10 min, and collect the cell lysis supernatant;

[0052] S4. The culture supernatant in S2 and the cell lysis supernatant in S3 are combined, and citric acid and maltodextrin are added to obtain metabolites of Lactobacillus rhamnosus LXW-1; wherein the weight ratio of citric acid to maltodextrin is about 1:15, and the sum of the weights of citric acid and maltodextrin accounts for 7% of the weight of the combined liquid.

[0053] Example 2 Toxicity Test

[0054] The MTT method was used to determine the effect of the metabolites of Lactobacillus rhamnosus LXW-1 obtained in Example 1 on the survival rate of human cloned colon adenocarcinoma cell Caco-2 cells.

[0055] Different concentrations of Lactobacillus rhamnosus LXW-1 metabolites were added to Caco-2 cells, and the survival of Caco-2 cells at different concentrations (0.25 mg / mL, 0.5 mg / mL, 1.0 mg / mL, 2.0 mg / mL) was observed; Lactobacillus rhamnosus LXW-1 metabolites were added to Caco-2 cells, and the survival of Caco-2 cells at different addition durations (24h, 48h) was observed.

[0056] The results are as follows Figure 2 As shown, Figure 2The white and black bars in the middle represent the experimental results of 24h and 48h addition respectively; "+" represents addition, and "-" represents no addition. For example, the white bar on the far left represents a blank reference without any addition. The second to fifth white bars from left to right represent the cell survival rate results after adding 0.25 mg / mL, 0.5 mg / mL, 1.0 mg / mL, and 2.0 mg / mL of Lactobacillus rhamnosus LXW-1 metabolites respectively; the black bar represents the expectation or analogy of the 48h experimental process based on the 24h data. The "administration" in the attached figure refers to the administration of Lactobacillus rhamnosus LXW-1 metabolites.

[0057] Figure 2 The results showed that with the increase of the added concentration of Lactobacillus rhamnosus LXW-1 metabolites (from 0 to 0.25 mg / mL, 0.5 mg / mL, 1 mg / mL, 2.0 mg / mL), the survival rate of colon adenocarcinoma cell Caco-2 did not decrease significantly, indicating that the above metabolites had no significant inhibitory effect on cell survival within a certain concentration range, and the metabolites of Lactobacillus rhamnosus LXW-1 had no obvious toxicity to cells, which is of great significance for evaluating the safety of Lactobacillus rhamnosus LXW-1 metabolites as potential biotherapeutics or health products.

[0058] Example 3 Anti-inflammatory effect of Lactobacillus rhamnosus LXW-1 metabolites

[0059] First, an LPS-induced inflammatory cell model was constructed, and then an experiment was carried out to analyze the inhibitory effect of Lactobacillus rhamnosus LXW-1 metabolites on cellular inflammation.

[0060] LPS 2.5 mg / mL was added to the cells (except for the blank control group, i.e. Figure 3 The white column on the far left of the middle left picture and Figure 3 The black column on the far left of the right figure), and then different concentrations of Lactobacillus rhamnosus LXW-1 metabolites (0.25 mg / mL, 0.5 mg / mL, 1.0 mg / mL, 2.0 mg / mL) were added to different experimental groups in turn, with "+" indicating addition and "-" indicating no addition; the changes of inflammatory factors IL-1β and IL-6 in the cell supernatant after 12h and 24h were observed.

[0061] The results are as follows Figure 3 , Figure 4As shown, "#" represents that there is a significant difference between the blank control group and the modeling group, and the modeling is successful; "*" represents whether there is a statistically significant difference compared with the control group. If there is a "*", it means that there is a significant difference. The more "*", the greater the significant difference. For other pictures in the accompanying drawings, please refer to the above explanations for "+", "-", "*", and "#". The drug administration group refers to the group to which the Lactobacillus rhamnosus LXW-1 metabolite of the present invention is added.

[0062] from Figure 3 , Figure 4 It can be seen that the addition concentration and addition time of Lactobacillus rhamnosus LXW-1 metabolites have an impact on the content of inflammatory factors IL-1β and IL-6 in the cell supernatant. For the addition concentration, the specific analysis is as follows:

[0063] As the added concentration of Lactobacillus rhamnosus LXW-1 metabolites increased (from 0.25 mg / mL to 0.5 mg / mL, 1.0 mg / mL, and 2.0 mg / mL), the concentrations of inflammatory factors IL-1β and IL-6 in the cell supernatant gradually decreased. Although low-concentration metabolite samples can also reduce the concentration of inflammatory factors, the effect is not obvious. Only when the concentration is 1.0 mg / mL and 2.0 mg / mL will there be a significant anti-inflammatory effect. According to the following trend, when the concentration reaches 1.0 mg / mL, the metabolite sample has a significant anti-inflammatory effect. When the concentration is further increased, the effect is expected to be equally significant. However, 1.0 mg / mL and 2.0 mg / mL can already achieve significant anti-inflammatory effects, and further increasing the concentration is not meaningful, so experiments with higher concentrations were not conducted.

[0064] From the attached Figure 4 It can be seen that the concentration of inflammatory factor IL-6 in the group 12 hours after adding the metabolites of Lactobacillus rhamnosus LXW-1 is lower than that in the group 24 hours after adding the metabolites of Lactobacillus rhamnosus LXW-1.

[0065] In order to further analyze the anti-inflammatory ability of Lactobacillus rhamnosus LXW-1 metabolites in different time periods, the anti-inflammatory ability analysis at different time points was carried out, and the four time points of 3 h, 6 h, 9 h, and 12 h were selected for determination. The experimental results are as follows: Figures 5 and 6 shown.

[0066] Figures 5 and 6 The results showed that within 3 hours after administration, in the 0.25 mg / mL, 0.5 mg / mL, 1 mg / mL, and 2 mg / mL groups, the concentrations of both IL-1β and IL-6 decreased with the increase of the administration concentration;

[0067] At 3 h, 6 h, 9 h, and 12 h after administration, the concentrations of IL-1β and IL-6 in the 0.25 mg / mL, 0.5 mg / mL, 1 mg / mL, and 2 mg / mL administration groups continued to decrease with time. At 12 h, the IL-1β concentration was relatively low compared to the three time periods of 3 h, 6 h, and 9 h. For IL-6, the concentrations of the two high-concentration administration groups of 1 mg / mL and 2 mg / mL were relatively low at 6 h, and the concentrations at 9 h and 12 h did not change significantly. This shows that as time goes on, the anti-inflammatory properties of the metabolites are still good, and the anti-inflammatory effect has not shown a particularly obvious decline.

[0068] Example 4 Western blotting to detect tight junction protein expression

[0069] Western Blot was used to detect the improvement of Lactobacillus rhamnosus LXW-1 metabolites on actin β-actin (42 kDa), cell junction protein Occludin (59 kDa) and ZO-1 (250 kDa). The concentrations of Lactobacillus rhamnosus LXW-1 metabolites were set to 1.0 mg / mL and 2.0 mg / mL, respectively.

[0070] The experimental results of the measurement are as follows Figure 7-8 As shown, Figure 7 The staining results of actin β-actin, cell junction protein Occludin and ZO-1 by Western Blot method are shown in Figure 1. The lighter the color of the band, the lower the tightness of the cell-cell connection; the lighter the color of the band, the tighter the cell connection;

[0071] Figure 8 The expression of related proteins by Lactobacillus rhamnosus LXW-1 metabolites. Figure 8 It can be seen that the high-concentration drug administration group has a significant promoting effect on the expression of cell junction proteins Occludin and ZO-1, which can enhance the tight junction level of tissue cells, that is, it can effectively inhibit inflammatory factors.

[0072] Example 5 In vivo animal model experiment

[0073] 5.1 Establishment of enteritis mouse model

[0074] Colitis was induced in mice by free drinking of dextran sulfate sodium (DSS), thus induced inflammatory bowel disease (IBD).

[0075] Since the first and most obvious feature of the IBD model is blood in the stool and weight loss, and blood in the stool is too subjective, we use the method of measuring weight to make an objective judgment, such as Fig. 9 As shown, the letters "C", "D", "M" and "A" represent "blank", "modeling group", "administration" and "sacrifice", respectively.

[0076] The mice were randomly divided into a blank control group (healthy mice, NOR), a modeling group (dextran sulfate sodium group, DSS group), and four concentrations of Lactobacillus rhamnosus LXW-1 metabolite administration groups (0.05 mg / kg, 0.1 mg / kg, 0.2 mg / kg, and 0.4 mg / kg), with 10 mice in each group.

[0077] The mice were in the adaptive culture stage from day 0 to day 6 without any intervention, and the treatment conditions in each group were blank (recorded as C, Control); the mice were fed with 2.8wt% DSS drinking water for 6 days to induce ulcerative colitis from day 7 to day 11, and four concentrations of Lactobacillus rhamnosus LXW-1 metabolite administration groups (0.05 mg / kg, 0.1 mg / kg, 0.2 mg / kg, 0.4 mg / kg) (recorded as MLF-1, 2, 3, 4 groups) were gavaged from day 12 to 29 for the recovery stage (treatment method recorded as M, i.e., MLF administration), and the modeling group (DSS group) continued to be treated without intervention (recorded as C, Control), and the mice were killed and dissected from day 20 to measure various indicators. During the modeling and treatment period, mice in each group had free access to water and food.

[0078] During the induction and recovery phases of ulcerative colitis, the survival status of mice in each group was tested every day and their body weight was recorded. The feces of mice were collected on the 6th and 15th days to observe the fecal viscosity and fecal bleeding. The disease activity index (DA1) was scored based on the weight loss rate, fecal viscosity and fecal bleeding. The specific scoring criteria for DAI of mice are shown in Table 1.

[0079] Table 1 Disease index (DAI) scoring standard for enteritis mice

[0080]

[0081] The mice were killed after 16 days, and their blood, colon tissue and mesenteric lymph nodes were collected. The blood was centrifuged at 2800r and 10000r for 5 min and 10 min, respectively, and serum samples were collected for enzyme-linked immunosorbent assay (ELISA). The colon tissue was photographed and the colon length was measured. The intestinal cavity was gently rinsed with sterilized phosphate-buffered saline (PBS) to remove intestinal materials. Part of the colon tissue was fixed in 4wt% paraformaldehyde solution for colon tissue staining and immunohistochemical analysis, and the rest was stored at -80℃ for later use.

[0082] MINs from mesenteric lymph nodes were ground and single cell suspensions were prepared for flow cytometric staining and analysis.

[0083] 5.2 Tissue staining

[0084] Colon tissue was fixed with 4% paraformaldehyde, then embedded in paraffin and stained with H&E method. The tissue staining sections were observed with Nikon Eclipse Ts2R+FL microscope, and the section results were scored histologically. The scoring criteria are shown in Table 2.

[0085] Histopathological score = inflammatory infiltration score + mucosal injury score + epithelial cell score

[0086] Table 2 Scoring criteria for mouse colon histopathology

[0087]

[0088] Note: “-” means it cannot be calculated

[0089] 5.3 Determination of inflammatory factor levels

[0090] Elisa kits (NOVUS Biologicals, USA) were used to measure the levels of serum inflammatory factors IL-1β and IL-6.

[0091] 5.4 Experimental Results Analysis

[0092] (1) Lactobacillus rhamnosus LXW-1 metabolites can alleviate DSS-induced ulcerative colitis in mice

[0093] from Fig.10 It can be seen that the enteritis mouse model was established by DSS induction method. After 20 days of body weight observation, it was found that except for the blank control group (NOR), the body weight of mice in other experimental groups showed a trend of first decreasing and then increasing, which was in line with expectations.

[0094] Fig.11The mouse disease index DAI showed that, except for the blank control group, all groups of mice showed symptoms of enteritis, and the disease index of each concentration group with added Lactobacillus rhamnosus LXW-1 metabolites was significantly lower than that of the modeling group (DSS group).

[0095] Colon pathological findings Figures 12-13 As shown, the results showed that the intestinal tissue length of the DSS group in the enteritis modeling group was significantly shorter than that of the blank control group (NOR group), while the group administered with the metabolite of Lactobacillus rhamnosus LXW-1 had a significant recovery.

[0096] (2) Tissue staining results

[0097] Colon tissue case section results are shown in Fig.14 It can be seen that the intestinal tissue in the DSS group had obvious lesions and significant inflammatory infiltration, and the 0.2 g / kg and 0.4 g / kg groups showed significant improvement.

[0098] The histological scores of the enteritis model mice under different treatment conditions were scored according to the colon tissue scoring criteria in Table 2. The results are shown in Fig.15 shown.

[0099] Combination Figures 14 and 15 It can be seen that the 0.2 g / kg and 0.4 g / kg administration groups had significant improvements on ulcerative colitis in mice.

[0100] (3) Levels of inflammatory factors in mouse serum

[0101] The results of the determination of inflammatory factors in the intestinal tissue of mice are as follows Figures 16 and 17 shown.

[0102] The results in the figure show that the inflammatory factors IL-1β and IL-6 in the groups treated with different concentrations of Lactobacillus rhamnosus LXW-1 metabolites were significantly lower than those in the positive control group DSS group, proving that it has a significant anti-inflammatory effect.

[0103] like Figures 18A-18D As shown, through ELISA and RT-PCR detection, the metabolite samples of Lactobacillus rhamnosus LXW-1 had a significant effect on reducing the level of inflammatory factors and showed a concentration gradient.

[0104] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. Use of a metabolite of Lactobacillus rhamnosus LXW-1 in preparing a product for treating ulcerative colitis, characterized in that: The Lactobacillus rhamnosus LXW-1 was deposited in the China Center for Type Culture Collection on May 20, 2024, with the deposit address: Wuhan University, Wuhan, China, with the deposit number: CCTCC NO: M 20241017, and the classification name: Lactobacillus rhamnosus LXW-1 Lactobacillus rhamnosus LXW-1; The metabolites of Lactobacillus rhamnosus LXW-1 are prepared by the following steps: Step S1. Cultivating Lactobacillus rhamnosus LXW-1 in MRS medium for 12 to 48 hours to obtain culture metabolites; Step S2. Centrifuging the culture metabolites obtained in step S1 to recover the culture supernatant and the biomass precipitate respectively; Step S3. Add 0.1-0.2M alkaline solution to the biomass precipitate recovered in step S2, stir for 20-30 minutes, centrifuge, and collect the cell lysis supernatant; Step S4. combining the culture supernatant in step S2 and the cell lysis supernatant in step S3, adding citric acid and dry matter to obtain metabolites of Lactobacillus rhamnosus LXW-1; The dry matter is selected from at least one of maltodextrin and cyclodextrin; the weight ratio of citric acid to dry matter is 1:10-20, and the sum of the weight of citric acid and dry matter accounts for 5-10% of the weight of the combined liquid.

2. The use according to claim 1, characterized in that The content of the metabolite of Lactobacillus rhamnosus LXW-1 in the product is 0.25-2.0 mg / mL.

3. The use according to claim 1, characterized in that The metabolites of Lactobacillus rhamnosus LXW-1 act by improving at least one of the levels of inflammatory factors and tight junction proteins in subjects with ulcerative colitis.

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