Mediterraneibacter faeces strain and application thereof in relieving metabolism-related fatty liver diseases

Abstract

The invention relates to the technical field of biology, and particularly discloses a Meditrraneibacter faeces strain and application of the Meditrraneibacter faeces strain in relieving of metabolism-related fatty liver diseases. The Mediterraneeibacter faeces strain found from faeces of healthy people can be applied to preventing, relieving and / or treating metabolism-related fatty liver diseases, animal experiment results show that hepatic cell fatty degeneration of mice is relieved, hepatic cell balloon-like degeneration is reduced, and hepatic cell liver-like degeneration is reduced. Therefore, the strain can improve liver fatty degeneration and inflammatory response of mice with metabolism-related fatty liver diseases. Moreover, by adopting the strain to interfere with the liver function and lipid metabolism of a mouse with the metabolism-related fatty liver disease, the levels of ALT, AST, TG, CHO and LDL in serum of the mouse with the metabolism-related fatty liver disease can be reduced.

Description

Technical Field

[0001] This application relates to the field of biotechnology, and particularly to a strain of Mediterraneibacter faeces and its application in alleviating metabolic associated fatty liver disease. Background Art

[0002] With the changes in diet structure and lifestyle transformation, metabolic associated fatty liver disease (MAFLD) is mainly characterized by fat deposition in the liver and diffuse macrovesicular steatosis of hepatocytes. Along with inflammatory responses and injury repair, it can further develop into metabolic associated steatohepatitis (MASH), and even cirrhosis and liver cancer. When the disease progresses to the MASH stage, it will also trigger extrahepatic diseases such as type 2 diabetes, chronic kidney disease, colorectal cancer, and cardiovascular high-risk severe diseases such as stroke and myocardial infarction. Although the FDA approved the first MASH treatment drug - resmetirom (Rezdiffra) in April this year, the remission rate of patients after 52 weeks of taking it is still no more than 30%. Therefore, finding compounds or microorganisms that can effectively treat MASH has become a hot spot and urgent need in global drug research and development.

[0003] The gut microbiota can directly affect liver homeostasis and disease progression through the "gut-liver axis". Lachnospiraceae is one of the core microbiota in the human gut. It colonizes the intestinal lumen from birth and its species richness and relative abundance increase throughout the host's life. Lachnospira participates in the metabolism of various carbohydrates and is also the main strain producing acetic acid and butyric acid. However, previous studies have reported that strains of different species in Lachnospiraceae have harmful or beneficial effects on human health. Currently, the role of strains of the genus Mediterraneibacter in the progression of MAFLD has not been reported so far. Summary of the Invention

[0004] The purpose of this application is to overcome the deficiencies of the above-mentioned prior art and provide a strain of Mediterraneibacter faeces and its application in alleviating metabolic associated fatty liver disease.

[0005] To achieve the above purpose, the technical solution adopted by this application is as follows: The present application provides a Mediterraneibacter faeces strain, which is Mediterraneibacter faecesGZSY1899, which was deposited in Guangdong Provincial Microbiological Culture Collection Center on August 7, 2024, with a deposit number of GDMCC No: 64990, a classification name of Mediterraneibacterfaeces, and a deposit address of 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou.

[0006] The present application isolates a strain of Mediterraneibacter faeces from healthy human feces and names it as Mediterraneibacter faecesGZSY1899. The strain of Mediterraneibacter faeces used in the present application belongs to Lachnospira, genus Mediterraneibacter.

[0007] The Mediterraneibacter faeces strain of the present application is round, translucent, and arranged individually in the improved GAM agar plate culture medium, is an anaerobic bacterium, and grows well at 37°C.

[0008] After extensive research and testing, the present application found that the Mediterraneibacterfaeces strain found in healthy human feces can be used to prevent, alleviate and / or treat metabolism-related fatty liver disease.

[0009] In some specific embodiments, the Mediterraneibacter faeces strain isolated in the present application was used to intervene in mice with metabolic-associated fatty liver disease, and the fatty degeneration of the liver cells of the mice was alleviated and the ballooning of the liver cells was reduced, indicating that the Mediterraneibacter faeces strain can improve the liver fatty degeneration and inflammatory response of mice with metabolic-associated fatty liver disease.

[0010] In addition, the use of Mediterraneibacter faeces strain to intervene in the liver function and lipid metabolism of mice with metabolic-associated fatty liver disease can downregulate ALT, AST, TG, CHO and LDL in mice with metabolic-associated fatty liver disease.

[0011] As a preferred embodiment of the Mediterraneibacter faeces strain described in the present application, the sequence of 16s rRNA of the Mediterraneibacter faeces strain is shown as SEQ ID NO:1.

[0012] This application provides a microbial preparation of the above-mentioned Mediterraneibacter faeces strain.

[0013] As a preferred embodiment of the microbial preparation described in this application, the concentration of the Mediterraneibacter faeces strain in the microbial preparation is 1-6×10 9 CFU / mL.

[0014] This application provides a drug of the above-mentioned Mediterraneibacter faeces strain or the microbial preparation.

[0015] As a preferred embodiment of the drug described in this application, the drug further comprises a pharmaceutically acceptable excipient; The excipient includes at least one of a stabilizer, a shaping agent, a solubilizer, and a diluent.

[0016] The excipient not only includes the types exemplified above, but also includes excipients commonly used in the art, such as surfactants, defoamers, thickeners, complexing agents, absorbents, moisturizers, binders, disintegrants, fillers, lubricants, wetting agents, chelating agents, osmotic pressure regulators and other excipients.

[0017] As a preferred embodiment of the drug described in this application, the dosage form of the drug includes at least one of a suspension, a granule, a capsule, a tablet, a pill, an oral liquid, and an injection.

[0018] This application provides the use of the above-mentioned Mediterraneibacter faeces strain or the microbial preparation in the preparation of a product for preventing, alleviating and / or treating metabolic associated fatty liver disease or metabolic associated steatohepatitis.

[0019] As a preferred embodiment of the use described in this application, the product has at least one of the effects of (1)-(5): (1) Reducing body weight and liver weight; (2) Improving liver tissue lesions, alleviating hepatocyte steatosis, and reducing hepatocyte ballooning; (3) Improving liver function and lipid metabolism, and down-regulating the contents of ALT, AST, CHO, TG and LDL; (4) Reducing the expression of inflammation-related cytokines and chemokines in liver tissue; (5) Reducing the expression of fibrosis-related genes in liver tissue, including liver fibrosis-related collagen and transforming growth factor-β.

[0020] This application also selected two typical animal models of metabolic associated fatty liver disease (MAFLD) and metabolic associated steatohepatitis (MASH) for experiments, namely: (1) Spontaneously diabetic type 2 mice (db / db) were given a Western diet high in fat, sugar, and cholesterol; (2) A high-fat diet with methionine and choline deficiency (HFMRCD), which can better simulate the disease process of metabolic associated fatty liver disease or metabolic associated steatohepatitis.

[0021] From the animal experiments, it can be seen that after intervention with the Mediterraneibacter faeces strain of this application, the body weight and liver weight of mice with metabolic associated fatty liver disease can be significantly reduced, and the fatty degeneration of hepatocytes in mice with metabolic associated fatty liver disease can be alleviated, and the ballooning degeneration of hepatocytes is reduced.

[0022] Moreover, after intervention with the Mediterraneibacter faeces strain of this application, the levels of ALT, AST, TG, CHO, and LDL in mice with metabolic associated fatty liver disease all decreased significantly (P<0.05), indicating that the treatment with the Mediterraneibacter faeces strain has a good effect on the inflammatory response in the treatment of metabolic associated fatty liver disease.

[0023] Using the Mediterraneibacter faeces strain of this application can also inhibit the levels of ALT and AST induced by a methionine-choline deficient diet (MCD), indicating that this Mediterraneibacter faeces strain can significantly improve the liver function indexes of mice with metabolic associated steatohepatitis (MASH).

[0024] In addition, compared with the WD model group, the expression of cytokines and chemokines related to liver tissue inflammation in the Mediterraneibacter faeces strain treatment group was significantly reduced, indicating that the Mediterraneibacter faeces strain also inhibited the expression of fibrosis-related genes.

[0025] Transcriptome sequencing of different groups of liver tissues showed that compared with the WD model group, the strain Mediterraneibacter faeces had a significant intervention on the expression of liver genes. Treatment with the strain Mediterraneibacter faeces caused a significant upregulation of 56 significantly differentially expressed genes (FDR < 0.05 and |log2FC| > 1) in liver tissues, and a decrease in the expression of 922 significantly differentially expressed genes (FDR < 0.05 and |log2FC| > 1). Compared with the WD group, treatment with the strain Mediterraneibacter faeces induced the expression of multiple fibrosis- and immunity-related pathways, among which the top two were ECM receptor interaction and focal adhesion. Treatment with the strain Mediterraneibacter faeces caused a significant decrease in the expression of genes related to the ECM receptor interaction and focal adhesion pathways, and these two pathways play key roles in the processes of liver inflammation and fibrosis. Therefore, it is suggested that the strain Mediterraneibacter faeces improves MAFLD by regulating the ECM receptor interaction and focal adhesion pathways in liver tissues.

[0026] As a preferred embodiment of the application described in the present application, the product includes a drug.

[0027] As a preferred embodiment of the application described in the present application, the drug further includes excipients.

[0028] As a preferred embodiment of the application described in the present application, the excipients include excipients and additives.

[0029] In some specific embodiments, the excipients include anti-adhesives, penetration enhancers, buffers, plasticizers, surfactants, defoamers, thickeners, complexing agents, absorbents, humectants, solvents, propellants, solubilizers, cosolvents, emulsifiers, colorants, pH regulators, binders, disintegrants, fillers, lubricants, wetting agents, chelating agents, osmotic pressure regulators, stabilizers, glidants, flavoring agents, preservatives, foaming agents, suspending agents, coating materials, fragrances, diluents, flocculants and deflocculants, filter aids, and release retardants.

[0030] As a preferred embodiment of the application described in the present application, the dosage form of the drug is granules, capsules, tablets, pills, or oral liquids.

[0031] The present application provides the use of the above-mentioned Mediterraneibacter faeces strain or the microbial preparation in the preparation of a product for reducing liver function indicators and blood lipid factor levels.

[0032] As a preferred embodiment of the application of the present application, the liver function indicators include alanine aminotransferase or aspartate aminotransferase; the blood lipid factors include at least one of triglyceride, total cholesterol and low density lipoprotein.

[0033] The Mediterraneibacter faeces strain of the present application can also be applied to foods, beverages, health products, enteral nutritional agents, dietary supplements, veterinary drugs or feed additives, and the application is not limited to the above applications.

[0034] Compared with the prior art, the present application has the following beneficial effects: The present application provides a Mediterraneibacter faeces strain and its application in alleviating metabolic associated fatty liver disease. The Mediterraneibacter faeces strain found from the feces of healthy people can be applied to the prevention, alleviation and / or treatment of metabolic associated fatty liver disease. From the results of animal experiments, it can be seen that the fatty degeneration of hepatocytes in mice is alleviated and the ballooning degeneration of hepatocytes is reduced, indicating that the use of the Mediterraneibacter faeces strain can improve the liver fatty degeneration and inflammatory response of mice with metabolic associated fatty liver disease. Moreover, by using the Mediterraneibacter faeces strain to intervene in the liver function and lipid metabolism of mice with metabolic associated fatty liver disease, the levels of ALT, AST, TG, CHO and LDL in the serum of mice with metabolic associated fatty liver disease can be down-regulated, indicating that the use of the Mediterraneibacter faeces strain has good curative effect in treating the inflammatory response of metabolic associated fatty liver disease. Description of the Drawings

[0035] Figure 1 It is a morphological diagram of the Mediterraneibacter faeces strain; Figure 2 It is an evolutionary tree of the Mediterraneibacter faeces strain; Figure 3 It is the treatment result diagram of WT mice using a low-fat and low-sugar control diet (CD), db / db diabetic mice using a low-fat and low-sugar control diet (CD), a Western diet (WD) and a microbial preparation containing Mediterraneibacter faeces GZSY1899 ( Figure 3In A, it shows the weight gain of mice in each group; Figure 3 In B, it shows the liver weights of mice in each group; Figure 3 In C, it shows the HE staining and oil red staining of liver tissues of mice in each group. Compared with db / db-WD, *P<0.05, **P<0.01, ***P<0.001); Figure 4 It is the result graph of the serum ALT, AST, TG, CHO, and LDL levels of mice in each group after WT mice were fed with a low-fat and low-sugar control diet (CD), db / db diabetic mice were fed with a low-fat and low-sugar control diet (CD), a Western diet (WD), and treated with a microbial preparation containing Mediterraneibacter faecesGZSY1899; Figure 5 It is the transcriptome sequencing graph of liver tissues taken after db / db diabetic mice were fed with a low-fat and low-sugar control diet (CD), a Western diet (WD), and treated with a microbial preparation containing Mediterraneibacter faecesGZSY1899 ( Figure 5 In A, it is the heat map of the expression levels of inflammation-related cytokines and chemokines; Figure 5 In B, it is the heat map of the expression levels of fibrosis-related genes); Figure 6 It is the transcriptome sequencing graph of liver tissues taken after db / db diabetic mice were fed with a low-fat and low-sugar control diet (CD), a Western diet (WD), and treated with a microbial preparation containing Mediterraneibacter faecesGZSY1899 ( Figure 6 In A, it is the principal component (PCA) analysis graph; Figure 6 In B, it is the volcano graph of significantly different genes between the WD vs WD-Mf groups, among which, there are 56 up-regulated genes and 922 down-regulated genes; Figure 6 In C, it is the KEGG signaling pathway graph of the WD vs WD-Mf groups); Figure 7 It is the transcriptome sequencing graph of liver tissues taken after db / db diabetic mice were fed with a low-fat and low-sugar control diet (CD), a Western diet (WD), and treated with a microbial preparation containing Mediterraneibacter faecesGZSY1899 ( Figure 7 In A, it is the heat map of the expression levels of genes related to the ECM receptor interaction (extracellular matrix receptor interaction) pathway; Figure 7 In B, it is the heat map of the expression levels of genes related to the focal adhesion pathway); Figure 8WT mice were fed a low-fat and low-sugar control diet (CD) and a high-fat diet with methionine and choline deficiency (HFMRCD) to construct a MASH model. The results of treating with the HFMRCD diet and a microbial preparation containing Mediterraneibacter faeces GZSY1899 are shown in the figure ( Figure 8 In A of Figure 8 , the HE staining, oil red staining, and Masson staining of the liver tissues of mice in each group are shown; Figure 8 In B and C of Figure 8 , the results of the serum ALT and AST levels of mice in each group are shown. Compared with HFMRCD, *P < 0.05, **P < 0.01, ***P < 0.001). Specific implementation manners

[0036] To better illustrate the purpose, technical solution, and advantages of the present application, the present application will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0037] In the following examples and comparative examples, unless otherwise specified, the experimental methods used are all conventional methods. The materials, reagents, etc. used, unless otherwise specified, can all be obtained from commercial channels, and the component raw materials used in each parallel experiment are the same.

[0038] Hereinafter, Mediterraneibacter faeces GZSY1899 is simply referred to as M.f.

[0039] Example 1. Isolation and screening of Mediterraneibacter faeces strains This example provides the steps for isolating and screening Mediterraneibacter faeces strains: First, collect the fecal samples of healthy donors with sterile tubes, place them on ice packs, and transfer them to an anaerobic workstation filled with CO 2 / H 2 / N 2 Wash, precipitate, and suspend the fecal samples three times with 0.01 M phosphate buffer (PBS, pH = 7.4), and then filter with a 40 μm cell sieve (FALCON) to remove insoluble particles. Continuously dilute the filtrate with anoxic PBS buffer supplemented with peptone (0.2% w / v) and l-cysteine (10 -1 -10 -7 times), and appropriate dilutions (10 -4 -10 -7Coated (by [multiple]) on the improved GAM agar plate medium (purchased from Qingdao Haibo Biotechnology #HB8462), and anaerobically cultured at 37°C for 2 to 10 days. Pick the single colonies that appear on the plate, perform 16S rRNA gene sequencing, transfer the target pure culture to liquid broth for further experiments, and transfer it to the agar slant in a Hungate tube for long-term preservation.

[0040] The formula of the improved GAM liquid medium is shown in Table 1: Table 1 Submit the amplified 16s rDNA sequence data to GenBank, and perform homology comparison using the online software Blast on the NCBI website; use the Maximum likelihood method in the bioinformatics analysis software MEGA-X to construct a phylogenetic tree to further identify the strain as Mediterraneibacter faeces.

[0041] Preserve the Mediterraneibacter faeces obtained by the above screening, named Mediterraneibacter faeces GZSY1899, which was preserved in the Guangdong Provincial Microbial Culture Collection Center on August 7, 2024, with the preservation number GDMCC No: 64990, the taxonomic name Mediterraneibacter faeces, and the preservation address: 5th Floor, Building 59, No. 100 Compound, Xianlie Middle Road, Guangzhou.

[0042] The Mediterraneibacter faeces strain of this application is round, semi-transparent, and arranged individually in the improved GAM agar plate medium (purchased from Qingdao Haibo Biotechnology #HB8462), belonging to anaerobic bacteria and growing well at 37°C, as Figure 1 shown.

[0043] The sequence of 16s rRNA of the Mediterraneibacter faeces strain is shown in SEQ ID NO: 1. The phylogenetic tree of the Mediterraneibacter faeces strain is as Figure 2 shown.

[0044] SEQ ID NO: 1 is:

[0045] Example 2, Microbial Inoculum Containing Mediterraneibacter faeces GZSY1899 This example provides a microbial inoculum containing Mediterraneibacter faeces GZSY1899 and a preparation method thereof. The preparation method includes the following steps: (1) Inoculate the glycerol bacteria of Mediterraneibacter faeces GZSY1899 in Example 1 into the YCFA liquid medium at an inoculation amount of 10%, and anaerobically and statically culture for 16 - 19 h to obtain a primary seed liquid; (2) Inoculate the primary seed liquid obtained in step (1) into the YCFA liquid medium at an inoculation amount of 4%, and anaerobically and statically culture for 7 - 9 h to obtain a secondary seed liquid; (3) Inoculate the secondary seed liquid obtained in step (2) into the YCFA liquid medium at an inoculation amount of 0.5%, and anaerobically and statically culture for 16 - 19 h to obtain a fermentation broth.

[0046] (4) Centrifuge the fermentation broth obtained in step (3) at 4°C and 8000 rpm for 7 min to obtain bacterial cells; (5) Resuspend the bacterial cells obtained in step (4) with phosphate buffer to obtain a bacterial sludge; (6) Mix the bacterial sludge obtained in step (5) with a cryoprotectant (5 wt% maltodextrin, 5 wt% polydextrose, 2.5 wt% trehalose, 2.5 wt% sucrose, 2.5 wt% lactose, 2.5 wt% glucose, 0.5 wt% arginine, 0.5 wt% histidine, and 79 wt% sterilized water), and store at -80°C; the volume ratio of the bacterial sludge to the cryoprotectant is 1:1, calculate the viable cell count after cryopreservation, and the concentration of Mediterraneibacter faeces GZSY1899 in the microbial inoculum is 5×10 9 CFU / mL.

[0047] Example 3, Experiment on Mediterraneibacter faeces GZSY1899 in Improving Metabolic Associated Fatty Liver Disease 1. Mediterraneibacter faeces GZSY1899 can reduce the body weight and liver weight of mice with metabolic associated fatty liver disease (MAFLD) and improve the liver tissue lesions in MAFLD mice.

[0048] In this application, 8-week-old BSK strain spontaneous diabetic mice (db / db) were selected and fed with a western diet to construct a model of metabolic associated fatty liver disease (MAFLD). There were 5 mice in each group. During the model establishment, the microbial preparation prepared in Example 2 (containing Mediterraneibacter faeces GZSY1899, with a dosage of 1×10 8 CFU / mouse) was administered by gavage once every other day. The body weight was measured every 3 days, and the experiment ended after 30 days.

[0049] As Figure 3 shown, wild-type (WT) mice were fed a low-fat and low-sugar control diet (CD), and db / db mice were fed a low-fat and low-sugar control diet (CD), a western diet (WD), or treated with a microbial agent containing Mediterraneibacter faeces GZSY1899, forming the following groups: WT-CD, db / db-CD, db / db-WD, db / db-WD-M.f.

[0050] Among them, Figure 3 A shows the body weight gain of mice in each group; Figure 3 B shows the liver weight of mice in each group; Figure 3 C shows the HE staining and oil red staining of liver tissues of mice in each group. Compared with db / db-WD, * P<0.05, ** P<0.01, *** P<0.001.

[0051] Figure 3 The results showed that compared with the mice in the db / db-WD group, the body weight of the mice in the db / db-WD-M.f group began to decrease significantly from the 12th day (P<0.05), and the liver weight of the mice was significantly reduced (P<0.01). Liver H&E staining and oil red O staining showed that compared with the mice in the WT-CD group, the mice in the db / db-WD group had severe diffuse fatty degeneration of hepatocytes, with a large number of lipid vacuoles visible, and ballooning degeneration was common in hepatocytes. Diffuse red lipid droplets were visible by oil red O staining. After administration of the isolated and screened Mediterraneibacter faeces GZSY1899, the fatty degeneration of hepatocytes in the db / db-WD-M.f group of mice was alleviated, and the ballooning degeneration of hepatocytes decreased. The above results indicate that the isolated and screened Mediterraneibacter faeces GZSY1899 in this application can significantly improve liver fatty degeneration and inflammatory response in MAFLD mice induced by a western diet.

[0052] 2. Mediterraneibacter faeces GZSY1899 can improve the liver function and lipid metabolism of MAFLD mice.

[0053] To study the effect of Mediterraneibacter faeces GZSY1899 on the liver function of MAFLD mice, this application detected the indexes of ALT (alanine amiotransferase), AST (aspartate aminotransferase), TG (Triglyceride), CHO (total cholesterol) and LDL (Low-Density Lipoprotein) in the serum of mice.

[0054] As Figure 4 shown, WT mice were fed a low-fat and low-sugar control diet (CD), and db / db mice were fed a low-fat and low-sugar control diet (CD), a Western diet (WD), and treated with a microbial preparation containing Mediterraneibacter faeces GZSY1899, constituting the following groups: WT-CD, db / db-CD, db / db-WD, db / db-WD-M.f.

[0055] The levels of ALT (alanine amiotransferase), AST (aspartate aminotransferase), TG (Triglyceride), CHO (total cholesterol) and LDL (Low-Density Lipoprotein) in the serum of mice in each group were detected.

[0056] From Figure 4 the results, it can be seen that compared with the WT-CD group of mice, the levels of ALT, AST, TG, CHO and LDL in the db / db-WD group of mice increased, indicating that there were serious abnormalities in liver function and lipid metabolism in the db / db-WD group of mice; after administration of Mediterraneibacter faeces GZSY1899, compared with the WT-CD group of mice, the levels of ALT, AST, TG, CHO and LDL in the db / db-WD-M.f group of mice decreased significantly (P<0.05).

[0057] 3. To further study the mechanism of M.f in improving MAFLD, liver tissues were taken for transcriptome sequencing after the experiment.

[0058] As Figure 5After db / db diabetic mice were fed a low-fat and low-sugar control diet (CD), a Western diet (WD), or treated with a microbial preparation containing Mediterraneibacter faecesGZSY1899, liver tissues were collected for transcriptome sequencing. Figure 5 In A, it is a heatmap of the expression levels of inflammation-related cytokines and chemokines; Figure 5 In B, it is a heatmap of the expression levels of fibrosis-related genes.

[0059] The results are as Figure 5 shown that compared with the WD group, the expression of inflammation-related cytokines and chemokines in the liver tissues of the M.f treatment group was significantly decreased, and M.f also inhibited the expression of fibrosis-related genes.

[0060] As Figure 6 shown, after db / db diabetic mice were fed a low-fat and low-sugar control diet (CD), a Western diet (WD), or treated with a microbial preparation containing Mediterraneibacter faecesGZSY1899, liver tissues were collected for transcriptome sequencing. Figure 6 In A, it is a principal component analysis (PCA) graph; Figure 6 In B, it is a volcano plot of significantly different genes in the WD vs WD-Mf group, among which, there are 56 up-regulated genes and 922 down-regulated genes; Figure 6 In C, it is a KEGG signaling pathway graph of the WD vs WD-Mf group.

[0061] Figure 6 In A, to analyze the relationship between each sample, principal component analysis (PCA) was performed on each sample according to the expression level. The results showed that there was an obvious separation between the liver samples of the control diet and the WD model group, while the transcriptional samples of the WD-M.f treatment group were clustered into one category, showing an obvious separation from the WD model group, suggesting that Mediterraneibacter faecesGZSY1899 had a significant intervention on the expression of liver genes.

[0062] Figure 6 In B, to determine which liver gene changes were affected by M.f treatment, edgeR software was used to screen for significantly different genes (FDR < 0.05 and |log 2 FC| > 1). Compared with WD, the treatment with Mediterraneibacter faecesGZSY1899 caused 56 genes to be significantly up-regulated and 922 genes to be down-regulated in the liver tissues.

[0063] Figure 6To determine the signaling pathways regulated by M. f, KEGG pathway enrichment analysis was performed on the genes with significant differences mentioned above. Compared with the WD group, the treatment with Mediterraneibacter faecesGZSY1899 induced the expression of multiple fibrosis- and immunity-related pathways, and the top two were ECM receptor interaction and focal adhesion.

[0064] Treatment with Mediterraneibacter faecesGZSY1899 significantly decreased the expression of genes related to the ECM receptor interaction and focal adhesion pathways, and these two pathways play key roles in the processes of liver inflammation and fibrosis.

[0065] As Figure 7 shown, after db / db diabetic mice were fed with a low-fat and low-sugar control diet (CD), a Western diet (WD), and treated with a microbial preparation containing Mediterraneibacter faecesGZSY1899, liver tissues were taken for transcriptome sequencing. Figure 7 Panel A shows the heatmap of the expression levels of genes related to the ECM receptor interaction (extracellular matrix receptor interaction) pathway; Figure 7 Panel B shows the heatmap of the expression levels of genes related to the focal adhesion pathway. Therefore, it is suggested that M. f improves MAFLD by regulating the ECM receptor interaction and focal adhesion pathways in liver tissues.

[0066] 4. To further prove the effect of Mediterraneibacter faecesGZSY1899 in improving MAFLD, this application selected 8-week-old wild-type C57 mice, fed them with a high-fat diet with methionine and choline deficiency (HFMRCD) to construct a MASH model, with 5 mice in each group. After 14 days of modeling, the microbial preparation prepared in Example 2 (containing Mediterraneibacter faecesGZSY1899, with a dosage of 1×10 8 CFU / mouse) was administered by gavage once every other day, and the experiment ended after 4 weeks.

[0067] As Figure 8As shown, WT mice were fed a control diet (MCS), a high-fat diet with methionine and choline deficiency (HFMRCD) to establish a MASH model, and the HFMRCD diet was used and treated with a microbial preparation containing Mediterraneibacter faeces GZSY1899 (HFMRCD-M.f) (the dosage used was 1×10 8 CFU / mouse), and the result graph ( Figure 8 In A of [Figure number], the HE staining, oil red staining, and Masson staining of the liver tissues of mice in each group are shown; Figure 8 In B and C of [Figure number], the result graphs of the serum ALT and AST levels of mice in each group are shown. Compared with HFMRCD, *P<0.05, **P<0.01, ***P<0.001).

[0068] After intervention with Mediterraneibacter faeces GZSY1899, the levels of ALT and AST induced by a methionine-choline-deficient diet (MCD) were inhibited, indicating that the use of Mediterraneibacter faeces GZSY1899 can significantly improve the liver function indexes of mice with metabolic associated steatohepatitis (MASH), thus indicating that Mediterraneibacter faeces GZSY1899 can change the phenotype of MASH mice.

[0069] In summary, the Mediterraneibacter faeces strain discovered from the feces of healthy humans in this application can be applied to the prevention, alleviation, and / or treatment of metabolic associated fatty liver disease. From the results of animal experiments, it can be seen that the fatty degeneration of hepatocytes in mice is alleviated and the ballooning degeneration of hepatocytes is reduced, indicating that the use of the Mediterraneibacter faeces strain can improve the liver fatty degeneration and inflammatory response of mice with metabolic associated fatty liver disease. Moreover, by intervening in the liver function and lipid metabolism of mice with metabolic associated fatty liver disease using the Mediterraneibacter faeces strain, the ALT, AST, TG, CHO, and LDL in mice with metabolic associated fatty liver disease can be down-regulated, indicating that the use of the Mediterraneibacter faeces strain has a good curative effect in treating the inflammatory response of metabolic associated fatty liver disease.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and not to limit the protection scope of this application. Although this application has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of this application can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of this application.

Claims

1. A strain of Mediterraneibacter faeces, characterized in that: The Mediterraneibacterfaeces strain is Mediterraneibacter faecesGZSY1899, which was deposited in the Guangdong Provincial Microbiological Culture Collection Center on August 7, 2024, with a deposit number of GDMCC No: 64990, and a deposit address of 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou.

2. The Mediterraneibacter faeces strain according to claim 1, characterized in that The sequence of 16s rRNA of the Mediterraneibacter faeces strain is shown in SEQ ID NO:

1.

3. A microbial preparation containing the Mediterraneibacter faeces strain according to claim 1 or 2.

4. The microbial preparation according to claim 3, characterized in that The concentration of the Mediterraneibacter faeces strain in the microbial preparation is 0.5-5×10 9 CFU / mL.

5. A medicament containing the Mediterraneibacter faeces strain according to claim 1 or 2 or the microbial preparation according to claim 3 or 4.

6. The drug according to claim 5, characterized in that The drug also includes pharmaceutically acceptable excipients; The auxiliary material includes at least one of a stabilizer, an excipient, a cosolvent, and a diluent.

7. The drug according to claim 5, characterized in that The dosage form of the drug includes at least one of suspension, granules, capsules, tablets, pills, oral liquid and injection.

8. Use of the Mediterraneibacter faeces strain according to claim 1 or 2 or the microbial preparation according to claim 3 or 4 in the preparation of a product for preventing, alleviating and / or treating metabolism-related fatty liver disease or metabolism-related fatty hepatitis.

9. The use according to claim 8, characterized in that The application is at least one of the following (1) to (5): (1) Reduce body weight and liver weight; (2) Improve liver tissue lesions, relieve fatty degeneration of liver cells, and reduce ballooning of liver cells; (3) Improve liver function and lipid metabolism, and reduce the levels of ALT, AST, CHO, TG, and LDL; (4) Reduce the expression of inflammation-related cytokines and chemokines in liver tissue; (5) Reduce the expression of fibrosis-related genes in liver tissue, including liver fibrosis-related collagen and transforming growth factor-β.

10. The use according to claim 8, characterized in that The products include pharmaceuticals.

11. Use of the Mediterraneibacter faeces strain according to claim 1 or 2 or the microbial preparation according to claim 3 or 4 in the preparation of a product for reducing liver function indexes and blood lipid factor levels.

12. The use according to claim 11, characterized in that The liver function index includes alanine aminotransferase or aspartate aminotransferase; the blood lipid factor includes at least one of triglycerides, total cholesterol and low-density lipoprotein.

Images