Application of β-alanine in preparing medicine for relieving colitis symptoms

Abstract

The present invention provides an application of β-alanine in the preparation of a drug for alleviating colitis symptoms. β-alanine is added to drinking water to activate pain receptors expressing MrgprD. Animal experimental results show that β-alanine can significantly improve the phenomenon of weight loss and colon shortening in mice by activating MrgprD pain receptors, reduce disease scores, and cause changes in microbial flora, thereby greatly improving the symptoms of colitis. Therefore, β-alanine can be used as a drug based on activating MrgprD pain receptors to treat colitis, and has good clinical application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of medicines, and in particular to application of beta-alanine in preparing a medicine for alleviating symptoms of colitis. Background Art

[0002] Ulcerative colitis (UC) is an inflammatory bowel disease with abdominal pain, diarrhea, bloody stools and weight loss as the main symptoms. It recurs repeatedly, has a long course and is difficult to cure. The specific pathogenesis is still unclear, but studies have shown that it is related to gastrointestinal mucosal immune system disorders and is affected by genetic, environmental and microbial factors. In recent years, studies have found that pain receptors can participate in immune regulation through signal transduction and play a protective role on peripheral tissues including the skin, lungs and gastrointestinal tract. Among them, pain neurons expressing MrgprD can relieve colitis. Based on this, the present application is intended to provide a new treatment method for clinical use of colitis. Summary of the invention

[0003] The present invention is made to solve the above problems, and aims to provide an application of beta-alanine in preparing a drug for relieving colitis symptoms.

[0004] The technical solution of the present invention is the use of beta-alanine in preparing a drug for alleviating colitis symptoms.

[0005] In the application of the β-alanine provided by the present invention in the preparation of a drug for alleviating colitis symptoms, the β-alanine may also have the following characteristics: the β-alanine is used to activate MrgprD pain receptors to alleviate colitis symptoms.

[0006] In the use of the β-alanine provided by the present invention in the preparation of a drug for alleviating colitis symptoms, the drug may also have the following characteristics: the colitis is ulcerative colitis.

[0007] In the use of the β-alanine provided by the present invention in the preparation of a drug for alleviating colitis symptoms, the drug may also have the following characteristics: the concentration of the β-alanine is 1%.

[0008] In the use of the β-alanine provided by the present invention in the preparation of a drug for alleviating colitis symptoms, the β-alanine may also have the following feature: the β-alanine is taken in the form of drinking water.

[0009] For mice with DSS-induced acute colitis, β-alanine significantly alleviated the symptoms of weight loss and colon shortening by activating MrgprD pain receptors, reduced disease scores, and caused changes in the intestinal microbial flora of mice, greatly improving the symptoms of colitis. Pathological tissue sections of β-alanine showed that it could inhibit intestinal edema and inflammatory cell infiltration, protect crypt structure, and promote goblet cell emptying.

[0010] Functions and Effects of the Invention

[0011] According to the use of β-alanine in the preparation of a drug for alleviating colitis symptoms, β-alanine is added to drinking water to activate the pain receptors expressing MrgprD. The results of animal experiments show that β-alanine can significantly improve the weight loss and colon shortening of mice by activating MrgprD pain receptors, reduce disease scores, and cause changes in microbial flora, greatly improving the symptoms of colitis. Therefore, β-alanine can be used as a drug based on activating MrgprD pain receptors to treat colitis, and has good clinical application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a processing flow chart of mice in Example 1 of the present invention;

[0013] Figure 2 1 is a graph showing weight changes (A) and colon length (B) of WT mice in Example 1 of the present invention;

[0014] Figure 3 This is a graph showing the weight change of WT mice treated with alanine only in Example 2 of the present invention;

[0015] Figure 4 The figure is a graph showing the weight change of WT and MrgprD-KO mice after DSS and alanine treatment (A), a graph showing the disease activity index on the 10th day (B), a graph showing the colon appearance on the 10th day (C), and a graph showing the colon length (D);

[0016] Figure 5 This is an H&E staining image of the pathological tissue section of the distal colon of the mouse treated on the 10th day in Example 4 of the present invention;

[0017] Figure 6 is a PAS staining image of a pathological tissue section of the distal colon of mice treated on the 10th day in Example 4 of the present invention;

[0018] Figure 7 This is a diagram of fecal microbial flora analysis of mice in Example 5 of the present invention on the 10th day after they were treated with alanine only. DETAILED DESCRIPTION

[0019] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is specifically described in the following embodiments in conjunction with the accompanying drawings.

[0020] Example 1

[0021] Experimental mice: WT (C57BL / 6J), 8 weeks.

[0022] Experimental groups: 3% DSS model group, 3% DSS + 1% β-Alanine treatment group, 5 mice in each group.

[0023] Figure 1 is a processing flow chart for mice.

[0024] like Figure 1 As shown, from day 0, 3% DSS was added to the drinking water of mice in each group for free drinking for 7 days to establish the acute colitis model in mice. 1% β-Alanine was added to the drinking water of mice in the 3% DSS + 1% β-Alanine treatment group 2 days in advance, and the mice in the 3% DSS model group drank ddH2O as a control. After 7 days, DSS was withdrawn from all groups, the mice in the 3% DSS + 1% β-Alanine treatment group continued to drink 1% β-Alanine, and the mice in the 3% DSS model group drank ddH2O. DSS drinking water was freshly prepared every 2 days and sterilized by filtration with a 0.22μm filter membrane.

[0025] From day 0, the weight of the mice was recorded every day, and the length of the colon was measured on day 10. The weight of the mice on day 0 was used as the base. Figure 2 The following are the weight changes (A) and colon length (B) of the two groups of mice. The results showed that the weight of the mice in the 3% DSS model group dropped significantly and their colons shortened, while the weight loss and colon shortening of the mice in the 3% DSS + 1% β-Alanine treatment group were alleviated.

[0026] Example 2

[0027] Experimental mice: WT (C57BL / 6J), 8 weeks.

[0028] Experimental groups: Control group, 1% β-Alanine treatment group, 5 mice in each group.

[0029] 1% β-Alanine was added to the drinking water of mice in the 1% β-Alanine treatment group, and ddH2O was used as a control for mice in the control group. The drinking water was freshly prepared every 2 days and sterilized by filtration with a 0.22 μm filter membrane.

[0030] From day 0, the weight of mice was recorded every day. On day 10, the feces of mice were collected for 16rRNA microbial identification, and the length of the colon of mice was measured. The weight of mice on day 0 was used as the base. Figure 3 The figure shows the weight changes of the two groups of mice. The results show that there is no significant difference in the weight of the two groups of mice, that is, 1% β-Alanine does not interfere with the weight of healthy mice.

[0031] Example 3

[0032] Experimental mice: WT (C57BL / 6J), MrgprD-KO, 8 weeks.

[0033] Experimental groups: WT group and MrgprD-KO group, 6 mice in each group.

[0034] Both WT and MrgprD-KO mice drank drinking water containing 1% β-Alanine two days in advance. From day 0 to day 7, both WT and MrgprD-KO mice drank drinking water containing 3% DSS and 1% β-Alanine for 7 consecutive days. DSS was withdrawn on day 7, and both WT and MrgprD-KO mice continued to drink drinking water containing 1% β-Alanine. DSS drinking water was freshly prepared every 2 days and sterilized by filtration using a 0.22 μm filter membrane.

[0035] From day 0, the weight of mice was recorded every day, and the disease activity index (DAI) of mice was evaluated. On day 10, the colon of mice was taken to observe the morphology and measure the length, and the distal colon was used for pathological sections.

[0036] The disease activity index of mice is divided into the following indicators: percentage of weight loss, shape of feces, rectal bleeding, and hair status. Percentage of weight loss: unchanged, 0 points; ≤5%, 1 point; 6%-10%, 2 points; 11%-20%, 3 points; >20%, 4 points. Fecal shape: normal, 0 points; pasty, 1 point; mucus, 2 points; blood, 3 points; all thin liquid with blood, 4 points. Rectal bleeding: no blood, 0 points; blood visible in the rectum, 1 point; blood visible on the fur, 2 points. Hair status: normal, 0 points; hair erect, 1 point; hair erect and lethargic, 2 points; lethargic hunchback, 3 points; immobility or weakness, 4 points. See Table 1 for details.

[0037] Table 1. Disease activity index of mice

[0038]

[0039] The weight of mice on day 0 was taken as the base. Figure 4 Figure 1 shows the weight change (A), disease activity index (B), colon morphology (C), and colon length (D) of the two groups of mice. The results showed that after DSS-induced colitis and β-Alanine treatment, only the colitis symptoms of the WT group of mice were alleviated, that is, weight recovery, decreased disease activity index, and reduced colon shortening, while the symptoms of the MrgprD-KO group of mice did not change. This suggests that β-Alanine can alleviate colitis symptoms by activating MrgprD pain neurons.

[0040] Example 4

[0041] According to the method in Example 3, the distal colon of mice (WT and MrgprD) treated with 3% DSS and 1% β-Alanine was obtained and placed in 4% PFA (Paraformaldehyde Solution) and fixed overnight at 4°C. The colon tissue was sent to Shanghai Ruchuang Company for embedding, sectioning, H&E staining and PAS staining.

[0042] Figure 5 The H&E staining results showed that after the WT group and MrgprD-KO group mice were treated with DSS-induced colitis and β-Alanine, the MrgprD-KO group mice showed colon edema, disappearance of crypt structure, and increased inflammatory cell infiltration, while the inflammation of the WT group mice was improved, that is, the colon and crypt structure were restored, and the inflammatory cell infiltration was reduced.

[0043] Figure 6 The PAS staining results showed that goblet cell emptying increased in the WT group.

[0044] The above results indicate that β-Alanine exerts a protective immune effect on DSS-induced acute colitis mice through MrgprD.

[0045] Example 5

[0046] According to the method in Example 2, the feces of mice in the control group and the 1% β-Alanine treatment group (WT) were collected, and the changes and proportions of the microbial flora in the mouse feces were detected based on 16srRNA.

[0047] Figure 7 This is a fecal microbial flora analysis chart of mice on the 10th day. The results show that there are differences in the microbial flora between the mice in the 1% β-Alanine treatment group, that is, the MrgprD activation group, and the control group. The probiotics such as Bifidobacteriaceae, Lactobacillaceae, Muribaculaceae, and Rikennellaceae increased in the MrgprD activation group, and the bacteria such as Bacteroides and Eyrsipelotrichaceae (negatively correlated with obesity) decreased.

[0048] Functions and Effects of the Embodiments

[0049] According to the application of β-alanine in the preparation of a drug for alleviating colitis symptoms involved in the above embodiment, β-alanine is added to drinking water to activate the pain receptors expressing MrgprD. The results of animal experiments show that β-alanine can significantly improve the weight loss and colon shortening of mice by activating MrgprD pain receptors, reduce disease scores, and cause changes in microbial flora, greatly improving the symptoms of colitis. Therefore, β-alanine can be used as a drug based on activating MrgprD pain receptors for the treatment of colitis, and has good clinical application prospects.

[0050] The above-mentioned embodiments are preferred examples of the present invention and are not intended to limit the protection scope of the present invention.

Claims

1. Use of β-alanine in preparing a drug for relieving colitis symptoms, wherein the colitis is ulcerative colitis, the concentration of the β-alanine is 1%, the β-alanine is taken in drinking water, and the β-alanine is used to activate MrgprD pain receptors. β-alanine significantly improves the phenomenon of weight loss and colon shortening in mice by activating MrgprD pain receptors, reduces disease scores, and causes changes in microbial flora, thereby greatly improving colitis symptoms.

Images