Postbiotic preparation for improving vascular elasticity and relieving hypertension and thrombus as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of microorganisms and biological medicines, and particularly relates to a postbiotic preparation for improving vascular elasticity and relieving hypertension and thrombus as well as a preparation method and application of the postbiotic preparation. Specifically, a strain of lactobacillus rhamnosus is obtained through screening, a postbiotic preparation is successfully developed based on the strain, and tests prove that the lactobacillus rhamnosus has the effects of reducing inflammatory response of vascular endothelium and reducing oxidative stress level so as to promote repair and regeneration of vascular endothelial cells, improve vascular elasticity and quickly improve hypertension; the anti-thrombus effect can be realized. Meanwhile, by optimizing the condition parameters of the preparation process of the metabolite preparation and combining anaerobic fermentation and aerobic fermentation on the lactobacillus rhamnosus, the advantage that metabolites are comprehensive and rich is achieved, and the metabolite preparation has good practical application value.

Description

Technical Field

[0001] This invention belongs to the field of microbial and biomedical technology, specifically relating to a post-biotic preparation that improves vascular elasticity, relieves hypertension and thrombosis, as well as its preparation method and application. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Hypertension is a clinical syndrome characterized by elevated systemic arterial blood pressure (systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, 1 mm Hg = 0.133 kPa), which may be accompanied by functional or organic damage to organs such as the heart, brain, and kidneys. Hypertension is divided into primary and secondary hypertension. Primary hypertension accounts for 90%-95% of cases and has diverse causes, mainly including unhealthy lifestyle habits and genetic factors. Unhealthy lifestyle habits include excessive salt intake, smoking, alcohol consumption, and being overweight. Secondary hypertension accounts for 5%-10% and is caused by other diseases, including diabetes, obesity, renal artery stenosis, pheochromocytoma, adrenal adenoma, or single-gene mutations. Hypertension is one of the most common chronic diseases and a major risk factor for cardiovascular and cerebrovascular diseases. If left untreated, long-term hypertension can lead to complications such as coronary heart disease, diabetes, heart failure, and kidney disease, seriously affecting human health and life. Spontaneous intracerebral hemorrhage (excluding those caused by aneurysms and arteriovenous malformations) is one of the most common acute and critical illnesses among the elderly, and it has attracted much attention due to its high mortality rate, high disability rate, high recurrence rate and high economic burden.

[0004] Human blood vessels, like water pipes, transport blood and are smooth, elastic channels. Vascular elasticity plays two roles: first, ensuring sufficient pressure within the vessels for blood to circulate throughout the body and perfuse organs; second, maintaining blood pressure within a safe range. Normally, healthy blood vessels have enough elasticity to control blood pressure vasodilation and vasoconstriction. However, with age, coupled with irregular lifestyles and diets, cholesterol levels increase, leading to excess fatty deposits that accumulate on the surface of blood vessels, eventually causing arteriosclerosis and loss of elasticity. High blood lipids and cholesterol increase blood viscosity, slowing blood flow and causing deposits to accumulate on the vessels. As these deposits accumulate, they gradually clog the vessels, further slowing blood flow. To maintain normal blood supply, the body instinctively raises blood pressure to promote blood flow. This is analogous to increasing water pressure to make it flow faster, resulting in hypertension. Long-term hypertension means that the pressure within the blood vessels remains consistently higher than normal. This sustained pressure places enormous tension on the vessel walls, which, over time, can lead to structural changes in the vessel walls. Hypertension and changes in vascular structure are the main causes of spontaneous intracerebral hemorrhage.

[0005] Studies have shown that epigenetic supplementation in early life stages may be a potential treatment strategy for preventing hypertension. Epigenetics is an emerging concept in the field of microbial preparations and products. Due to its advantages such as high safety, strong stability, and convenient storage, it has potential applications in food, medical, and cosmetic fields; however, the research and development of related products is still in its early stages. Currently, no epigenetic preparations have been found to improve hypertension, nor have they been found to improve vascular elasticity. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a post-biotic preparation for improving vascular elasticity, alleviating hypertension and thrombosis, along with its preparation method and applications. Specifically, animal and human trials have verified that the post-biotic preparation obtained by this invention effectively improves vascular elasticity and alleviates hypertension, effectively solving the problems of significant side effects, poor therapeutic efficacy, and strong drug dependence associated with existing treatments. This invention is thus completed based on the above research findings.

[0007] To achieve the above-mentioned technical objectives, the present invention relates to the following technical solutions: In one aspect of the present invention, a strain of Lactobacillus rhamnosus ( Lactobacillus rhamnosus Leeco-gxy, deposited at the China Center for Type Culture Collection (address: Wuhan University, Luojia Mountain, Wuchang, Wuhan, Hubei Province), on November 24, 2025, with accession number CCTCC NO: M 20252657.

[0008] A second aspect of the present invention provides a postbiotic preparation containing at least the above-mentioned (inactivated) Lactobacillus rhamnosus and / or its fermentation metabolites.

[0009] A third aspect of the present invention provides a method for preparing the above-mentioned postbiotic formulation, the method comprising: S1. Strain activation: The Lactobacillus rhamnosus Leeco-gxy was placed in an activation medium to obtain a pure strain. S2. Preparation of primary seed culture: Select a single colony of Lactobacillus rhamnosus Leeco-gxy obtained in step S1 and place it in the first culture medium for static culture to obtain primary seed culture. S3. Preparation of secondary seed culture: Inoculate the above primary seed culture into the second culture medium and let it stand for culture to obtain the secondary seed culture.

[0010] S4. Preparation of tertiary seed culture: Inoculate the above-mentioned secondary seed culture into the third culture medium and stir to obtain the tertiary seed culture; S5. Anaerobic and aerobic fermentation of Lactobacillus rhamnosus: The above three-stage seed culture is inoculated into the fourth culture medium. Anaerobic fermentation is maintained first, followed by aerobic fermentation for a period of time.

[0011] A fourth aspect of the present invention provides the use of the above-mentioned post-biotic preparation in the preparation of products that improve vascular elasticity and relieve hypertension and thrombosis.

[0012] The beneficial technical effects of one or more of the above technical solutions are as follows: The above-mentioned technical solution screened and obtained a strain of *Lactobacillus rhamnosus*. Based on this strain, a metabiotic preparation was successfully developed. Experimental verification showed that it reduces inflammatory responses in vascular endothelium, lowers oxidative stress levels, thereby promoting the repair and regeneration of vascular endothelial cells, improving vascular elasticity, and can rapidly improve hypertension. It also exhibits antithrombotic effects. Furthermore, by optimizing the preparation process parameters of this metabiotic preparation and combining anaerobic and aerobic fermentation of *Lactobacillus rhamnosus*, the preparation achieved a comprehensive and abundant range of metabolites, demonstrating good practical application value. Attached Figure Description

[0013] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0014] Figure 1 The blood pressure of rats in each group after feeding with the biogen was measured in the experiment to verify the effectiveness of the present invention.

[0015] Figure 2The images show the pathological results of the aorta in each group of rats during the efficacy verification experiment of this invention.

[0016] Figure 3 The results of thrombus weight in different groups of rats in the experiment to verify the effectiveness of the present invention.

[0017] Figure 4 The levels of SOD (A) and MDA (B) in different groups of rats were measured in the experiment to verify the effectiveness of the present invention.

[0018] Figure 5 The images show the venous pathology results of rats in each group during the efficacy verification experiment of this invention. Detailed Implementation

[0019] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0020] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0021] In a typical embodiment of the present invention, a strain of Lactobacillus rhamnosus is provided. Lactobacillus rhamnosus Leeco-gxy, deposited at the China Center for Type Culture Collection (address: Wuhan University, Luojia Mountain, Wuchang, Wuhan, Hubei Province), on November 24, 2025, with accession number CCTCC NO: M 20252657.

[0022] In another specific embodiment of the present invention, a postbiotic preparation is provided, which contains at least the above-mentioned (inactivated) Lactobacillus rhamnosus and / or its fermentation metabolites.

[0023] In another specific embodiment of the present invention, the postbiotic preparation comprises inactivated Lactobacillus rhamnosus and its fermentation metabolites, wherein the fermentation metabolites include, but are not limited to, polysaccharides, polypeptides and amino acids.

[0024] In another specific embodiment of the present invention, a method for preparing the above-mentioned postbiotic preparation is provided, the method comprising: S1. Strain activation: The Lactobacillus rhamnosus Leeco-gxy was placed in an activation medium to obtain a pure strain. S2. Preparation of primary seed culture: Select a single colony of Lactobacillus rhamnosus Leeco-gxy obtained in step S1 and place it in the first culture medium for static culture to obtain primary seed culture. S3. Preparation of secondary seed culture: Inoculate the above primary seed culture into the second culture medium and let it stand for culture to obtain the secondary seed culture.

[0025] S4. Preparation of tertiary seed culture: Inoculate the above-mentioned secondary seed culture into the third culture medium and stir to obtain the tertiary seed culture; S5. Anaerobic and aerobic fermentation of Lactobacillus rhamnosus: The above three-stage seed culture is inoculated into the fourth culture medium. Anaerobic fermentation is maintained first, followed by aerobic fermentation for a period of time.

[0026] In step S1, the activation culture medium comprises the following components: casein 0.05-0.2%, sialic acid 0.05-0.2%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, agar powder 1.5-2.0%, and pH adjusted to 6.5. In step S2, the culture temperature is 28-30℃ and the culture time is 12-14 hours; The first culture medium has the following composition: casein 0.05-0.2%, natto powder 0.05-0.1%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, and pH adjusted to 6.5; In step S3, the inoculation amount is controlled at 0.1-5% (preferably 0.5%). v / v The incubation temperature is 30-40℃ (preferably 37℃), and the incubation time is 10-12 hours. The composition of the second culture medium is as follows: casein 0.05-0.2%, natto powder 0.05-0.1%, sialic acid 0.05-0.2%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, adjusted to pH 6.5; In step S4, the inoculum amount is controlled at 0.5-5% (preferably 2%); the specific culture conditions are: stirring culture at 20-50 rpm (preferably 30 rpm), temperature at 30-40℃ (preferably 37℃), tank pressure at 0.03-0.06 MPa (preferably 0.05 MPa), and culture for 10-12 hours; The composition of the third culture medium is as follows: casein 0.05-0.2%, fructooligosaccharides 0.1-0.2%, natto powder 0.05-0.1%, sialic acid 0.05-0.2%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, adjusted to pH 6.5; In step S5, the fourth culture medium has the following composition: isomaltooligosaccharide 3%, casein 0.2%, peptone 2%, fructooligosaccharide 5%, water-soluble starch 3%, Tween-80 0.1%, glycine 0.5%, tyrosine 0.5%, natto powder 0.05-0.1%, sialic acid 0.05-0.2%, tomato 0.05-0.1%, pH natural.

[0027] Specifically, the fermentation method in step S5 includes: inoculating the above-mentioned third-stage seed liquid into the fourth culture medium for anaerobic fermentation, with an inoculation amount of 0.5-5% (preferably 2%), at 37 °C, 40-50 r / min (preferably 45 r / min), maintaining the tank pressure at 0.05 MPa with sterile nitrogen, and culturing for 8-10 hours; subsequently, keeping the stirring speed constant, lowering the temperature to 35 °C, maintaining the tank pressure at 0.05 MPa with sterile air, and culturing for 4-5 hours, adding 0.05-0.2% (preferably 0.1%) of peptidoglycan by volume of the fermentation liquid, and cooling to 20 °C and maintaining for 30 minutes to obtain the final product.

[0028] Furthermore, step S5 also includes the steps of freeze-drying the obtained fermentation product and pulverizing it into powder.

[0029] In another specific embodiment of the present invention, the above-mentioned post-biotic preparation is provided for use in the preparation of products that improve vascular elasticity and relieve hypertension and thrombosis.

[0030] Furthermore, the products that improve vascular elasticity and relieve hypertension and thrombosis can be food or medicine.

[0031] More specifically, the medicine may also include at least one other inactive pharmaceutical ingredient.

[0032] The inactive pharmaceutical ingredient can be a carrier, excipient, or diluent commonly used in pharmaceuticals. Furthermore, it can be formulated into oral dosage forms such as powders, granules, suspensions, emulsions, syrups, and sprays using conventional methods. The non-pharmaceutical active ingredients that may be included, such as carriers, excipients, and diluents, are well known in the art, and those skilled in the art can determine that they meet clinical standards.

[0033] In another specific embodiment of the present invention, the carrier, excipient and diluent include, but are not limited to, lactose, glucose, sucrose, sorbitol, mannitol, xylitol, erythritol, maltitol, starch, gum arabic, alginate, gelatin, calcium phosphate, calcium silicate, cellulose, methylcellulose, microcrystalline cellulose, polyvinylpyrrolidone, water, methylparaben, propylparaben, talc, magnesium stearate and mineral oil, etc.

[0034] The following examples further illustrate the present invention, but do not constitute a limitation thereof. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0035] In each embodiment, the composition of the activation culture medium is as follows: casein 0.2%, sialic acid 0.1%, beef extract 0.3%, peptone 2%, sodium acetate 0.05%, potassium dihydrogen phosphate 0.05%, agar powder 2.0%, and pH adjusted to 6.5; The first culture medium consisted of: 0.1% casein, 0.1% natto powder, 0.3% beef extract, 0.5% peptone, 0.05% sodium acetate, and 0.05% potassium dihydrogen phosphate, with the pH adjusted to 6.5.

[0036] The second culture medium consisted of: casein 0.05-0.2%, natto powder 0.05-0.1%, sialic acid 0.05-0.2%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, and pH adjusted to 6.5.

[0037] The third culture medium consisted of the following: casein 0.2%, fructooligosaccharides 0.2%, natto powder 0.1%, sialic acid 0.2%, beef extract 1.0%, peptone 0.5%, sodium acetate 0.05%, potassium dihydrogen phosphate 0.05%, and pH adjusted to 6.5.

[0038] The fourth culture medium consisted of the following: 3% isomaltooligosaccharide, 0.2% casein, 2% peptone, 5% fructooligosaccharide, 3% water-soluble starch, 0.1% Tween-80, 0.5% glycine, 0.5% tyrosine, 0.05% natto powder, 0.1% sialic acid, 0.05% tomato, and natural pH.

[0039] The percentage of each component in the culture medium is a mass-volume percentage, expressed in g / mL.

[0040] Example 1 The Lactobacillus rhamnosus Lactobacillus rhamnosusLeeco-gxy was streaked onto the activation medium to obtain a pure strain. Single colonies of Lactobacillus rhamnosus Leeco-gxy obtained in the previous step were picked and placed in the first culture medium at 30 ℃ for 12 hours to obtain the first seed culture. The above-mentioned primary seed culture was inoculated into the second culture medium at an inoculation rate of 0.5% and incubated at 37 ℃ for 12 hours to obtain the secondary seed culture. The secondary seed culture was then inoculated into a seed tank containing the third culture medium under aseptic conditions at an inoculation rate of 2%, stirred at 30 rpm, at a temperature of 37 ℃, pH 7.0, and a tank pressure of 0.05 MPa for 10 hours to obtain the tertiary seed culture. The above-mentioned three-stage seed culture was inoculated into a fermenter containing sterile culture medium at an inoculation rate of 2%. The fermentation was carried out at 37 °C, 45 r / min, and sterile nitrogen was used to maintain the pressure in the fermenter at 0.05 MPa for 10 hours. After 10 hours, the stirring speed remained unchanged, the temperature was reduced to 35 °C, and sterile air was used to maintain the pressure in the fermenter at 0.05 MPa for 5 hours. Then, sterile peptidoglycan at 0.1% of the fermentation liquid volume was added to the fermenter, the temperature was lowered to 20 °C and maintained for 30 minutes, and then freeze-dried and pulverized to obtain powder.

[0041] Example 2 The Lactobacillus rhamnosus Lactobacillus rhamnosus Leeco-gxy was streaked onto the activation medium to obtain a pure strain. Single colonies of Lactobacillus rhamnosus Leeco-gxy obtained in the previous step were picked and placed in the first culture medium at 30°C for 12 hours to obtain the first seed culture. The above-mentioned primary seed culture was inoculated into the second culture medium at an inoculation rate of 0.5% and incubated at 37 ℃ for 12 hours to obtain the secondary seed culture. The secondary seed culture was then inoculated into a seed tank containing the third culture medium under aseptic conditions at an inoculation rate of 2%, stirred at 30 rpm, at a temperature of 37 ℃, pH 7.0, and a tank pressure of 0.05 MPa for 10 hours to obtain the tertiary seed culture. The above-mentioned three-stage seed culture was inoculated into a fermenter containing sterile culture medium at an inoculation rate of 2%. The fermentation was carried out at 37 °C, 45 r / min, and sterile nitrogen was used to maintain the pressure in the fermenter at 0.05 MPa for 15 hours. After 15 hours of cultivation, sterile peptidoglycan at a volume of 0.1% of the fermentation broth was added to the fermenter. The temperature was lowered to 20 °C and maintained for 30 minutes. The mixture was then freeze-dried and pulverized to obtain powder.

[0042] Example 3 The Lactobacillus rhamnosus Lactobacillus rhamnosus Leeco-gxy was streaked onto the activation medium to obtain a pure strain. Single colonies of Lactobacillus rhamnosus Leeco-gxy obtained in the previous step were picked and placed in the first culture medium at 30°C for 12 hours to obtain the first seed culture. The above-mentioned primary seed culture was inoculated into the second culture medium at an inoculation rate of 0.5% and incubated at 37 ℃ for 12 hours to obtain the secondary seed culture. The secondary seed culture was then inoculated into a seed tank containing the third culture medium under aseptic conditions at an inoculation rate of 2%, stirred at 30 rpm, at a temperature of 37 ℃, pH 7.0, and a tank pressure of 0.05 MPa for 10 hours to obtain the tertiary seed culture. The above-mentioned three-stage seed culture was inoculated into a fermenter containing sterile culture medium at an inoculation rate of 2%. The fermentation was carried out at 37 °C, 45 r / min, and sterile air to maintain a pressure of 0.05 MPa for 15 hours. After 15 hours of cultivation, sterile peptidoglycan at a volume of 0.1% of the fermentation broth was added to the fermenter. The temperature was lowered to 20 °C and maintained for 30 minutes. The mixture was then freeze-dried and pulverized to obtain powder.

[0043] Effect verification 1. Rat experiment (1) Verification of efficacy in treating hypertension Ten clean-grade Wistar rats and forty clean-grade spontaneously hypertensive rats (SHR rats) were acclimatized for one week. Ten rats were designated as the normal control group, and the forty SHR rats were randomly divided into four groups (n=10): a model group, Example 1 group, Example 2 group, and Example 3 group. Groups in Examples 1, 2, and 3 received 75 mg / kg of probiotics via gavage once daily, while the normal control and model groups received an equal volume of physiological saline via gavage once daily. After eight weeks of treatment, the rats' systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured. After anesthesia and sacrifice, arterial tissue was collected. The levels of TNF-α, IL-1β, and IL-6 in the arterial tissue were detected by enzyme-linked immunosorbent assay (ELISA). Aortic pathological examination was performed using hematoxylin and eosin (HE) staining. Furthermore, Western blotting was used to detect the levels of collagen and elastin in the arterial tissue.

[0044] The results showed that before administration, the blood pressure values ​​of the model group, Example 1 group, Example 2 group and Example 3 group were significantly higher than those of the normal group. After 8 weeks of treatment, compared with the model group, the blood pressure of rats in Example 2 group and Example 3 group was basically unchanged, while the blood pressure of Example 1 group was significantly reduced and tended to be normal.

[0045] Compared with the normal group, the levels of TNF-α, IL-6 and IL-1β in the arterial tissue homogenate of the model group rats were significantly increased. After treatment with Example 1 (combination of aerobic and anaerobic fermentation), the levels of TNF-α, IL-6 and IL-1β were significantly reduced. This shows that the intervention of the post-biotic (i.e., Example 1) through the combination of aerobic and anaerobic fermentation can effectively reduce the levels of TNF-α, IL-6 and IL-1β in rat arterial tissue.

[0046] Table 1. Levels of TNF-α, IL-1β and IL-6 in rats of each group

[0047] In the normal group, the aortic wall of rats was of moderate thickness, and the adventitia was a thin layer of loose connective tissue. Compared with the normal group, the model group rats showed pathological changes such as significantly thickened aortic wall, roughened intima, thickened media, and enlarged and disordered arrangement of endothelial and smooth muscle cells. Compared with the model group, the above-mentioned morphological and structural pathological changes in the aorta of the Example 1 group were improved to varying degrees.

[0048] (2) Verification of antithrombotic efficacy Ten clean-grade Wistar rats and 40 clean-grade DTV rats (DTV rats) constructed using the modified Reyers method were used. After 1 week of acclimatization, the 10 rats were set as the normal group, and the 40 DTV rats were randomly divided into 4 groups (n=10) using a random number table: model group, Example 1 group, Example 2 group and Example 3 group. In Examples 1, 2, and 3, patients were given 75 mg / kg of probiotics by gavage once daily. The normal and model groups were given an equal volume of physiological saline by gavage once daily. After 8 weeks of continuous treatment, blood was collected from the abdominal aorta and thrombus tissue was obtained: ① Thrombus wet weight determination: Inferior vena cava thrombi were separated, blotted dry with filter paper, and weighed; ② Serum superoxide dismutase (SOD) activity was measured using the xanthine oxidase method, and malondialdehyde (MDA) content was measured using the thiobarbituric acid method; ③ Pathological morphological observation: Thrombus tissue was fixed in 4% paraformaldehyde, embedded in paraffin, sectioned, stained with hematoxylin and eosin (HE), and observed under a light microscope for inflammatory cell infiltration and vascular structure; ④ RT-PCR was used to detect the mRNA expression of ICAM-1 in rat femoral vein tissue, and its relative expression level was calculated using the 2-ΔΔCt method; Western blot was used to detect the protein expression level of intercellular adhesion molecule-1 (ICAM-1) in thrombus tissue. Statistical methods were employed, with SPSS 26.0 software used for data processing and Graphpad Prism 9.0 software used for graph creation.

[0049] Compared with the normal group (thrombus wet weight 0 mg, no thrombus formation), the thrombus wet weight in the model group rats was significantly increased (147.54±15.17 mg). Compared with the model group, the thrombus wet weight in Example 1 group was significantly decreased (71.30±9.03 mg, P<0.01). Compared with the normal group, the SOD activity in the model group rats was decreased and the MDA content was increased. Compared with the model group, the SOD activity in Example 1 group was increased (P<0.01), and the MDA content was significantly decreased (P<0.01).

[0050] Intercellular adhesion molecule-1 (ICAM-1) is a transmembrane glycoprotein located on the cell surface, belonging to the immunoglobulin superfamily, and is mainly expressed on the surface of vascular endothelial cells, leukocytes, and other tissue cells. Its core function is to mediate cell adhesion and signal transduction, playing a crucial role in physiological and pathological processes such as inflammatory responses, immune regulation, and thrombosis. ICAM-1 participates in the thrombosis process by enhancing the interaction between platelets and endothelial cells, promoting thrombus development. In diseases such as deep vein thrombosis (DVT), ICAM-1 expression levels are often significantly elevated, becoming an important indicator reflecting vascular endothelial inflammation and thrombosis risk. RT-qPCR and Western blot results showed that, compared with the normal group, the expression of ICAM-1 mRNA and protein in the model group was upregulated, while compared with the model group, the expression of ICAM-1 mRNA and protein in the Example 1 group was significantly downregulated, with statistically significant differences (P < 0.05).

[0051] Table 2. Effects of post-biotics on ICAM-1 in rats

[0052] HE staining results showed that no thrombus formation was observed in the portal vein of the normal group rats, and the vascular intima was continuous and intact; mixed thrombus formation was observed in the lumen of the model group, with disordered endothelial cells, infiltration of a large number of inflammatory cells, and thrombus embedded in the vascular wall; the post-genetic group (Example 1 group) showed intact vascular smooth muscle cell morphology, reduced inflammatory exudation, and loose thrombus structure.

[0053] 2. Small-scale population experiment Thirty participants aged 35-65 years who volunteered for the trial and were able to complete questionnaires and record information, and who were suffering from essential hypertension (systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg), were included in the experimental group. They took 600 mg of Postbiotic (prepared in Example 1) orally every morning on an empty stomach for 4 weeks. During this period, they completed questionnaires to monitor improvement. They maintained their normal dietary habits during the treatment.

[0054] After the course of treatment, 100% of users reported a significant improvement in their high blood pressure.

[0055] Table 3. Statistical data of the hypertensive post-vitamin population trial.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A strain of Lactobacillus rhamnosus ( Lactobacillus rhamnosus Leeco-gxy, deposited at the China Center for Type Culture Collection on November 24, 2025, with accession number CCTCC NO: M 20252657.

2. A post-biotic preparation, characterized in that, It contains the Lactobacillus rhamnosus of claim 1 and / or its fermentation metabolites.

3. The method for preparing the post-biotic preparation according to claim 2, characterized in that, The preparation method includes: S1. Strain activation: The Lactobacillus rhamnosus Leeco-gxy was placed in an activation medium to obtain a pure strain. S2. Preparation of primary seed culture: Select a single colony of Lactobacillus rhamnosus Leeco-gxy obtained in step S1 and place it in the first culture medium for static culture to obtain primary seed culture. S3. Preparation of secondary seed culture: Inoculate the above primary seed culture into the second culture medium and let it stand for culture to obtain the secondary seed culture. S4. Preparation of tertiary seed culture: Inoculate the above-mentioned secondary seed culture into the third culture medium and stir to obtain the tertiary seed culture; S5. Anaerobic and aerobic fermentation of Lactobacillus rhamnosus: The above three-stage seed culture is inoculated into the fourth culture medium. Anaerobic fermentation is maintained first, followed by aerobic fermentation for a period of time.

4. The preparation method according to claim 3, characterized in that, In step S1, the composition of the activation culture medium is as follows: casein 0.05-0.2%, sialic acid 0.05-0.2%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, agar powder 1.5-2.0%, and pH adjusted to 6.

5.

5. The preparation method according to claim 3, characterized in that, In step S2, the culture temperature is 28-30℃ and the culture time is 12-14 hours; The first culture medium consists of the following components: casein 0.05-0.2%, natto powder 0.05-0.1%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, and pH adjusted to 6.

5.

6. The preparation method according to claim 3, characterized in that, In step S3, the inoculation amount is controlled at 0.1-5% (preferably 0.5%). v / v The incubation temperature is 30-40℃ (preferably 37℃), and the incubation time is 10-12 hours. The second culture medium consists of the following components: casein 0.05-0.2%, natto powder 0.05-0.1%, sialic acid 0.05-0.2%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, and pH adjusted to 6.

5.

7. The preparation method according to claim 3, characterized in that, In step S4, the inoculum amount is controlled at 0.5-5% (preferably 2%); the specific culture conditions are: stirring culture at 20-50 rpm (preferably 30 rpm), temperature at 30-40℃ (preferably 37℃), tank pressure at 0.03-0.06 MPa (preferably 0.05 MPa), and culture for 10-12 hours; The composition of the third culture medium is as follows: casein 0.05-0.2%, fructooligosaccharides 0.1-0.2%, natto powder 0.05-0.1%, sialic acid 0.05-0.2%, beef extract 0.3-1.0%, peptone 0.5-2%, sodium acetate 0.05-0.2%, potassium dihydrogen phosphate 0.05-0.2%, adjusted to pH 6.

5.

8. The preparation method according to claim 3, characterized in that, In step S5, the fourth culture medium has the following composition: isomaltooligosaccharide 3%, casein 0.2%, peptone 2%, fructooligosaccharide 5%, water-soluble starch 3%, Tween-80 0.1%, glycine 0.5%, tyrosine 0.5%, natto powder 0.05-0.1%, sialic acid 0.05-0.2%, tomato 0.05-0.1%, pH natural; Specifically, the fermentation method in step S5 includes: inoculating the above-mentioned third-stage seed liquid into the fourth culture medium for anaerobic fermentation, with an inoculation amount of 0.5-5% (preferably 2%), at 37 °C, 40-50 r / min (preferably 45 r / min), maintaining the tank pressure at 0.05 MPa with sterile nitrogen, and culturing for 8-10 hours; subsequently, keeping the stirring speed constant, lowering the temperature to 35 °C, maintaining the tank pressure at 0.05 MPa with sterile air, and culturing for 4-5 hours, adding 0.05-0.2% (preferably 0.1%) of peptidoglycan by volume of the fermentation liquid, and cooling to 20 °C and maintaining for 30 minutes to obtain the final product.

9. The preparation method according to claim 8, characterized in that, Step S5 further includes the steps of freeze-drying the obtained fermentation product and pulverizing it into powder.

10. The use of the post-biotic preparation of claim 2 or the post-biotic preparation prepared by any one of claims 3-9 in the preparation of products that improve vascular elasticity and relieve hypertension and thrombosis.

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