Application of dietary fiber in preparation of product for relieving atrial remodeling after acute myocardial infarction
Through dietary fiber, the intestinal microbiota metabolite IPA is regulated, and the STING pathway is inhibited, which solves the atrial reconstruction problem caused by intestinal microbiota disorder and achieves the relief effect of atrial reconstruction.
Patent Information
- Application Number
- CN202311853967.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-29
- Publication Date
- 2025-07-01
AI Technical Summary
The prior art has not yet clarified the relationship between intestinal flora and its metabolites and atrial reconstruction after acute myocardial infarction, and there is no report on whether dietary fiber can reverse atrial reconstruction.
Dietary fiber intervention is used to regulate the level of indole-3-propionic acid (IPA), the intestinal flora metabolite, inhibit the STING pathway, reduce the succinate content, and alleviate atrial remodeling.
Dietary fiber dietary intervention significantly alleviates atrial remodeling after acute myocardial infarction. By increasing IPA, it reduces succinate, reduces atrial STING expression, and improves atrial electrical conduction and fibrosis.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the field of biomedicine. Specifically, the present invention discloses an application of dietary fiber in alleviating atrial remodeling after acute myocardial infarction. Background Art
[0002] Acute myocardial infarction (AMI) is a common acute and critical cardiovascular disease in clinical practice, and a large number of patients develop heart failure after AMI. Atrial remodeling affects ventricular filling and overall cardiac function, increases the risk of atrial arrhythmias, and exacerbates the process of heart failure after AMI. Magnetic resonance imaging examination found that atrial remodeling can occur within one week after AMI, and the cardiovascular adverse events of patients with atrial remodeling are significantly increased. Some studies suggest that the proportion of atrial infarction caused by direct ischemia of atrial branch vessels is only 7.7%, and non-ischemic factors are the main causes of atrial remodeling after AMI. Currently, the molecular mechanism of atrial remodeling after AMI is not clear and worthy of in-depth study.
[0003] Abnormalities of the gut microbiota and its metabolites are important causes of atrial remodeling and concurrent atrial fibrillation (AF). At the same time, some studies have shown that AMI can also cause gut microbiota disorders and abnormal metabolites. However, whether the changes in gut microbiota and its metabolites are related to atrial remodeling after AMI has not been reported.
[0004] In addition, previous studies have suggested that dietary fiber can alleviate myocardial remodeling through the gut microbiota metabolite pathway. However, whether dietary fiber can reverse atrial remodeling after AMI has not been reported. Summary of the Invention
[0005] The present invention provides an application of a substance that inhibits the STING pathway in the preparation of a product for alleviating atrial remodeling.
[0006] Furthermore, the product is a food or a drug.
[0007] Furthermore, the substance that inhibits the expression of stimulator of interferon genes in the atrium is indole-3-propionic acid.
[0008] Furthermore, the substance that inhibits the expression of stimulator of interferon genes in the atrium is C-176.
[0009] Furthermore, the substance that inhibits the expression of stimulator of interferon genes in the atrium is dietary fiber.
[0010] Furthermore, the atrial remodeling is atrial remodeling caused by acute myocardial infarction.
[0011] The present invention also provides a product for alleviating atrial remodeling.
[0012] Furthermore, the atrial remodeling is atrial remodeling caused by acute myocardial infarction.
[0013] The present invention also claims the application of dietary fiber in any of the following:
[0014] 1) Preparing a food for inhibiting the STING pathway;
[0015] 2) Preparing a food for reducing the accumulation of ROS;
[0016] 3) Preparing a food for inhibiting the expression level of atrial STING;
[0017] 4) Preparing a food for alleviating atrial remodeling.
[0018] Furthermore, the atrial remodeling is atrial remodeling caused by acute myocardial infarction.
[0019] The present invention discovers that in a mouse model of anterior wall AMI constructed by ligating the left anterior descending branch, the metabolite succinic acid of the gut microbiota is significantly increased, and the expression of atrial stimulator of interferon genes (STING) is increased. Thus, the abnormality of the gut microbiota and its metabolites after AMI may be an important cause of atrial remodeling after AMI.
[0020] The present invention discovers that dietary fiber dietary intervention can alleviate the gut microbiota disorder after AMI; the production of the gut microbiota metabolite indole-3-propionic acid (IPA) is significantly increased, succinic acid is reduced, and atrial remodeling is significantly alleviated. Based on this, dietary fiber alleviates the gut microbiota disorder after AMI, increases the gut microbiota metabolite IPA and reduces succinic acid, which is an important mechanism for it to reduce atrial remodeling after AMI. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 . Effects of interventions such as dietary fiber and antibiotics on atrial remodeling and atrial STING expression in AMI mice; wherein, A. Echocardiogram; B. Epicardial electrical mapping (left atrium); C. Atrial ROS fluorescence staining; D. Atrial Masson staining; E. Left atrial diameter and left ventricular ejection fraction; F. Left atrial conduction time, conduction velocity and dispersion; G. Atrial ROS fluorescence staining; H. Atrial Masson staining; I. Atrial STING expression based on Western blot.
[0022] Figure 2. Effects of interventions such as dietary fiber and antibiotics on the intestinal flora and plasma metabolic profiles of AMI mice; A. Dilution curve; B. Alpha diversity (Shannon index); C. Principal coordinates analysis (PCoA) based on Bray_curtis; D. Partial least squares discriminant analysis (PLS-DA).
[0023] Figure 3 . Effects of AMI on the intestinal flora and plasma metabolic profiles of mice; A. Non-metric multidimensional scaling analysis (NMDS) based on bray_curtis; B. Bar chart of the abundances of the top 10 phylum-level species; C. Orthogonal partial least squares discriminant analysis (OPLS-DA).
[0024] Figure 4 . Effects of AMI on the plasma metabolic profiles of mice; A. Pie chart of differential metabolites between groups based on the Class level; B. Bubble chart of the contribution based on Simper analysis.
[0025] Figure 5 . Effects of dietary fiber on the intestinal flora and plasma metabolic profiles of AMI mice; A. Non-metric multidimensional scaling analysis (NMDS) based on bray_curtis; B. Bar chart of the abundances of the top 10 phylum-level species; C. Orthogonal partial least squares discriminant analysis (OPLS-DA).
[0026] Figure 6 . Effects of dietary fiber on the intestinal flora and plasma metabolic profiles of AMI mice; A. Heatmap of the correlations between differential metabolites and species between AMI and the high dietary fiber group; Box plots of succinic acid (B) and IPA (C).
[0027] Figure 7 . Effects of succinic acid and IPA on the accumulation of ROS and fibrosis in the atria of mice; A. Fluorescent staining of atrial ROS; B. Masson staining of the atria; C. Expression of atrial STING.
[0028] Figure 8 . Effects of succinic acid, IPA, and STING inhibitor on the accumulation of ROS and the expression of STING in HL-1 cells; A. DHE staining; B. Expression of STING based on Western blot.
[0029] Figure 9 . IPA alleviates the accumulation of ROS in HL-1 cells; DHE staining. Specific implementation manners
[0030] The present invention will be further described in detail below in conjunction with specific embodiments. The provided embodiments are only for clarifying the present invention, rather than limiting the scope of the present invention. The following embodiments can be used as a guide for those of ordinary skill in the art to make further improvements, and do not limit the present invention in any way.
[0031] Unless otherwise specified, the experimental methods in the following embodiments are all conventional methods, and are carried out according to the techniques or conditions described in the literature in this field or according to the product instructions. The materials, reagents, etc. used in the following embodiments can be obtained from commercial channels unless otherwise specified.
[0032] Example 1 Relationship between STING gene and atrial remodeling after AMI
[0033] STING was reported by the Glen N Barber team in 2008. It produces type I interferons in a Toll-like receptor-independent manner. It is widely expressed in multiple organ tissues of the human body and is an adaptor protein on the endoplasmic reticulum membrane. As an innate immune component of cells, previous studies have mostly been related to antiviral and tumor. After double-stranded DNA from pathogens, tumor cells, and self-cells enters the cytoplasm, it activates the cytoplasmic DNA sensor cyclic GMP-AMP synthase (cGAS); catalyzes the synthesis of the second messenger cyclic GMP-AMP, which changes the conformation of STING and activates it, and then translocates to the Golgi apparatus; recruits TANK-binding kinase 1 (TBK1) and IκB kinase, activates downstream interferon regulatory factor 3 (IRF3) and NF-κB, phosphorylates IRF3 and translocates it into the nucleus; promotes the production of type I interferons and pro-inflammatory factors, and further exerts a pro-inflammatory effect.
[0034] Previous studies have shown that STING is also significantly activated in various cardiac remodeling diseases. Endoplasmic reticulum stress during myocardial hypertrophy can be activated through STING, leading to the activation of NF-κB and an increase in transforming growth factor-β1 (TGF-β1), exacerbating the development of myocardial fibrosis, myocardial inflammation, etc. As mentioned above, such key molecular biological and pathophysiological processes of promoting cardiac remodeling are also important pathophysiological bases for the occurrence of atrial remodeling. This suggests that the STING pathway may also play an important regulatory role in the process of atrial remodeling.
[0035] For the above reasons, in this embodiment, a mouse model of atrial remodeling after AMI was constructed to detect the protein expression level of the STING gene in atrial tissue. The specific method is as follows:
[0036] 1. Mouse experiment
[0037] Animal grouping and intervention method: Male SPF-grade C57bl / 6 mice aged 6 - 8 weeks (Beijing Vital River Laboratory Animal Technology Co., Ltd.) were selected and fed with sterile drinking water and normal diet (5% cellulose) (Jiangsu Medison Biomedical Co., Ltd., MDDZ280), and randomly divided into: control group, sham operation group, and AMI group.
[0038] Among them, the AMI group was used to construct an AMI mouse model by ligating the left anterior descending branch: induced and maintained under anesthesia with 4%, 1.5% isoflurane, opened the chest cavity at the 3rd and 4th intercostal spaces on the left margin of the sternum (incision about 1.2 - 1.5 cm), gently squeezed and exposed the heart at the 4th intercostal space, quickly inserted a 6-0 suture needle 2 mm below the lower edge of the left atrial appendage, exited the needle at the connection between the pulmonary artery conus and the apex of the heart on the right side of the heart, and ligated the left anterior descending branch visually to completely block blood flow.
[0039] Sham operation group: Only passed a short suture through the left anterior descending branch without ligation.
[0040] Meanwhile, to evaluate the effect of intestinal flora on atrial remodeling after AMI, an antibiotic drinking water group (Abx) was established: Ampicillin (Apexbio, A2510 - 5g) 0.5 g / L, Neomycin (Apexbio, B1795 - 10g) 0.5 g / L, Vancomycin (Apexbio, B1223 - 1g) 0.25 g / L, Metronidazole (Apexbio, B1976 - 10g) 0.5 g / L. Detection was carried out 7 days after the intervention.
[0041] 2. Verification experiment
[0042] The following detection experiments were carried out on the atrial remodeling mouse model after AMI constructed in step 1:
[0043] 1) Atrial STING expression: Detect the expression of STING (Proteintech, 19851 - 1 - AP - 50ul) by Western blot.
[0044] 2) Atrial remodeling: (1) Echocardiography was used to evaluate various indexes of the cardiac structure and function of mice: the anteroposterior diameter of the left atrium and the left ventricular ejection fraction. (2) Atrial tissue pathology: The cardiac tissue of mice was taken and fixed. After dehydration, paraffin sections were made. Tissue morphological methods such as Masson staining and ROS fluorescence staining were used to detect pathological changes such as the fibrotic area and ROS content in the atrial tissue of mice. (3) The atrial conduction velocity and dispersion were detected by epicardial electrical mapping. Mice were intraperitoneally injected with sodium heparin (100 U / 20 g) and anesthetized by CO2 inhalation; after sampling, the aorta was quickly connected to the cannula, and the Langendorff perfusion system was connected. A Mapping Lab matrix multi-channel electrode was placed on the epicardium of the left atrium. After stabilization, the stimulating electrode was inserted into the root of the aortic arch to record the baseline signal, and the electrophysiological mapping system recorded the signal.
[0045] The results are as Figure 1 shown. Based on echocardiography, epicardial electrical mapping, ROS fluorescence staining, Masson staining, and Western blot, the effects of different intervention methods on atrial remodeling were evaluated, and the detection was carried out after 7 days. Compared with the control group (CTR) and the sham operation group (Sham), AMI caused an increase in the atrial inner diameter (see Figure 1 A, E), abnormal electrical conduction (see Figure 1 B, F), ROS accumulation (see Figure 1 C, G), and fibrosis (see Figure 1 D, H) changes, and at the same time, there was an increase in the expression of atrial STING (see Figure 1 I), while antibiotic drinking water (Ab) intervention could significantly alleviate the above conditions. The results showed that the expression level of atrial STING was significantly correlated with atrial remodeling.
[0046] Example 2 The role of substances regulating the STING pathway in regulating atrial remodeling
[0047] The level of gut microbiota metabolites plays a crucial role in the process of atrial remodeling, and it is still unclear whether gut microbiota metabolites can also play an important regulatory role in the process of atrial remodeling after AMI.
[0048] The gut microbiota is an important source of succinic acid in the body. The content of succinic acid in germ-free mice is significantly reduced; intestinal ischemia / reperfusion causes an increase in succinic acid-producing bacteria and a decrease in consuming bacteria in the intestine, resulting in an increase in succinic acid in the body. Using broad-spectrum antibiotics to weaken the gut microbiota can inhibit this change; succinic acid can cause apoptosis of alveolar epithelial cells and acute lung injury; and the plasma succinic acid level in patients is significantly correlated with acute lung injury after intestinal ischemia / reperfusion. Succinic acid may be a new target for the treatment of intestinal source-induced host target organ inflammatory injury. Therefore, the reduction of succinic acid may also be an important intermediate metabolite mediating the reverse effect of dietary fiber on cardiac remodeling.
[0049] For the above reasons, in this example, the regulatory effect of the gut microbiota metabolite succinic acid on atrial remodeling after AMI was evaluated. Through metabolite supplementation experiments and in vitro experiments, the regulatory effect of succinic acid on atrial remodeling such as atrial ROS accumulation and fibrosis was confirmed. The specific methods are as follows:
[0050] 1. Determination of substances that regulate atrial remodeling and STING expression after AMI based on the levels of gut microbiota metabolites
[0051] 16S amplicon sequencing: Fresh feces were collected, and total DNA of fecal samples was extracted using a fecal DNA extraction kit (QIAGEN, Germany). The V4 region of the bacterial 16S rRNA gene was amplified based on universal primers. Sequencing analysis was performed based on the Illumina HiSeq 2500 sequencing platform, and bioinformatics analysis such as species annotation was performed after quality control. Metabolomics detection based on liquid chromatography-mass spectrometry (LC-MS) technology, as well as quantitative detection of succinic acid and IPA, was used to evaluate the changes in metabolic characteristics and the levels of specific metabolites.
[0052] The results showed that: First, based on 16S transcriptome sequencing and plasma untargeted metabolomics detection, the effects of different intervention methods on the gut microbiota composition and circulating metabolic profile were evaluated. Compared with the control group (CTR) and the sham operation group (Sham), AMI and antibiotic drinking water (Abx) significantly changed the gut microbiota structure (see Figure 2 A-C therein) and the plasma metabolic profile (see Figure 2 D therein). Among them, compared with the sham operation group (Sham), AMI significantly changed the gut microbiota composition (see Figure 3 A-B therein) and the plasma metabolic profile (see Figure 3 C therein).
[0053] Further analysis of the effects of AMI on the gut microbiota and plasma metabolic profile of mice found that: Carboxylic acids and their derivatives were the metabolites with the highest proportion of differences between the sham operation group (Sham) and the AMI group (see Figure 4 A). Simper analysis was performed on the metabolites at this Class level, and succinic acid had the highest contribution (see Figure 4 B).
[0054] 2. Stimulatory effect of succinic acid on atrial remodeling
[0055] 2.1 Mouse experiments
[0056] Construction of the succinate metabolite anaplerotic model: Male SPF C57bl / 6 mice at 6 - 8 weeks of age were selected and intervened for 7 days. Succinate (8 mM / kg, 8:00 AM, once a day) (Apexbio, N1941 - 100 mg) was injected intraperitoneally. Based on atrial ROS fluorescence staining, Masson staining, and Western blot, the effects of intraperitoneal injection of succinate on atrial tissue pathology and STING expression were evaluated.
[0057] The results showed that succinate caused atrial ROS accumulation (see Figure 7 A), fibrosis (see Figure 7 B), and increased STING expression (see Figure 7 ).
[0058] 2.2 In vitro experiments
[0059] HL - 1 cells were intervened for 24 hours under stimulation with or without succinate (2 mmol / L), STING inhibitor C - 176 (MCE, HY - 112906) (1 μmol / L), etc. Based on DHE staining and Western blot, the effects of succinate on atrial remodeling indexes of HL - 1 cells were evaluated.
[0060] The results showed that succinate caused ROS accumulation and increased STING expression. The STING inhibitor C - 176 could significantly reduce the changes in ROS accumulation and increased STING expression caused by succinate (see Figure 8 ).
[0061] Example 3. Dietary fiber relieves atrial remodeling by inhibiting the atrial STING pathway
[0062] Dietary fiber can significantly relieve atrial remodeling, and the intermediate medium for its relief of atrial remodeling may also be intestinal flora metabolites. As a metabolite of intestinal flora metabolizing tryptophan, when IPA is inhibited, it will lead to enhanced activation of T cells, resulting in increased myocardial infiltration, thus exacerbating cardiac remodeling manifestations such as fibrosis and heart failure. Previous studies have also suggested that IPA can reduce the expression of chondrocyte inflammatory factors induced by interleukin (IL) - 1β and inhibit the NF - κB pathway. As mentioned above, NF - κB activation is one of the common molecular mechanisms of various cardiac remodeling. This suggests that an increase in IPA may be an important intermediate metabolite for dietary fiber to relieve cardiac remodeling.
[0063] For the above reasons, this example evaluated the effects of high-fiber diet (High fiber) intervention on atrial remodeling and gut microbiota in AMI mice. Further, through metabolite supplementation experiments and in vitro experiments, the inhibitory effect of IPA on atrial remodeling such as atrial ROS accumulation and fibrosis caused by succinic acid was confirmed. The specific methods are as follows:
[0064] 1. Mouse experiments
[0065] 1.1 Animal grouping and intervention methods
[0066] Construct an AMI mouse model with dietary fiber intervention (AMI+High fiber mice): Select male SPF-grade C57bl / 6 mice at 6-8 weeks of age and intervene for 7 days: ligate the left anterior descending branch + sterile drinking water + high-fiber diet (5% cellulose + 15% inulin).
[0067] Metabolite supplementation experiment: Select male SPF-grade C57bl / 6 mice at 6-8 weeks of age and intervene for 7 days. Inject succinic acid intraperitoneally (8 mM / kg, 8:00 AM, once a day) + inject IPA (Apexbio, M1047-100mg) intraperitoneally (20 mg / Kg, 15:00 PM, once a day).
[0068] 1.2 Detection
[0069] 1) According to the method of "2. Verification experiment" in Example 1, detect the atrial remodeling conditions of the two groups of mice respectively. The results are as Figure 1 shown. The results show that mice fed a high-fiber diet can inhibit atrial remodeling after AMI, specifically manifested as alleviated atrial electrical conduction abnormalities, fibrosis, and ROS accumulation. At the same time, detect the effect of dietary fiber intervention on atrial STING expression. The results are as Figure 1 shown in I. The results show that mice fed a high-fiber diet can reduce the expression of STING.
[0070] 2) According to the method of "1. Determination of substances regulating atrial remodeling and STING expression based on gut microbiota metabolite levels" in Example 2, detect the gut microbiota and plasma metabolites of the two groups of mice respectively. The results are as Figures 2 to 6 shown. Dietary fiber can alleviate gut microbiota disorders after AMI, and dietary fiber intervention significantly increases the gut microbiota metabolite IPA and reduces the microbiota metabolite succinic acid that increases significantly after AMI.
[0071] 3) According to the method of "2.2 In vitro experiment" in Example 2, detect the effect of IPA metabolite supplementation on atrial ROS accumulation and fibrosis caused by succinic acid. The results are as Figure 7As shown, IPA has an inhibitory effect on succinate-induced atrial ROS accumulation, fibrosis, and STING expression.
[0072] The above experiments showed that by intervening in AMI mice with a high-fiber diet, it was found that the high-fiber diet could not only increase the level of IPA and decrease the level of succinate, but also quantitatively observe that it could reduce the atrial STING expression level and alleviate atrial remodeling after AMI.
[0073] 2. In vitro experiments
[0074] HL-1 cells (Beijing Na Biotechnology, BNCC288890) were intervened for 24 hours under stimulation with or without succinate (2 mmol / L) and IPA (100 μmol / L).
[0075] Based on DHE staining and Western blot, the effects of IPA on succinate-induced ROS accumulation and increased STING expression in HL-1 cells were evaluated.
[0076] IPA intervention could significantly reduce succinate-induced ROS accumulation and increased STING expression in HL-1 cells (see Figure 8 ). In addition, H2O2 (Sigma, 323381-25ML) induced ROS accumulation in HL-1 cells, while intervention with the STING inhibitor C-176 or IPA could significantly alleviate this change (see Figure 9 ).
[0077] AMI causes atrial remodeling and gut microbiota dysbiosis, and dietary fiber can relieve atrial remodeling. The experimental results suggest that AMI leads to gut microbiota dysbiosis in mice, increased succinate, a metabolite of gut microbiota, accompanied by increased atrial STING expression, slowed atrial conduction velocity, atrial ROS accumulation, and atrial fibrosis; dietary fiber alleviates gut microbiota dysbiosis after AMI, increases the gut microbiota metabolite IPA, decreases succinate, and significantly alleviates the above conditions. In vitro experiments found that IPA could relieve the increased STING expression and ROS accumulation in HL-1 cells caused by succinate via STING.
[0078] The above details the present invention. For those skilled in the art, without departing from the purpose and scope of the present invention and without unnecessary experiments, the present invention can be implemented within a relatively wide range under equivalent parameters, concentrations, and conditions. Although specific embodiments of the present invention are given, it should be understood that the present invention can be further improved. In short, according to the principle of the present invention, this application intends to include any changes, uses, or improvements to the present invention, including changes made using conventional techniques known in the art that depart from the scope disclosed in this application. Some basic features can be applied according to the scope of the following appended claims.
Claims
1. Use of a substance that inhibits the STING pathway in the preparation of a product for relieving atrial remodeling.
2. The application according to claim 1, characterized in that, The product is a food or a drug.
3. The application according to claim 1, characterized in that, The substance that inhibits the expression of stimulator of interferon genes in the atrium is indole-3-propionic acid.
4. The application according to claim 1, characterized in that The substance that inhibits the expression of stimulator of interferon genes in the atrium is C-176.
5. The application according to claim 1, characterized in that, The substance that inhibits the expression of stimulator of interferon genes in the atrium is dietary fiber.
6. The use according to any one of claims 1-5, wherein the atrial remodeling is atrial remodeling caused by acute myocardial infarction.
7. A product for relieving atrial remodeling according to any one of claims 1-6.
8. The product according to claim 7, wherein The atrial remodeling is atrial remodeling caused by acute myocardial infarction.
9. Use of dietary fiber in any of the following: 1) Preparation of a food that inhibits the STING pathway; 2) Preparation of a food that reduces the accumulation of ROS; 3) Preparation of a food that inhibits the expression level of atrial STING; 4) Preparation of a food that relieves atrial remodeling.
10. The use according to claim 6, wherein the atrial remodeling is atrial remodeling caused by acute myocardial infarction.