Lactobacillus plantarum IOB602 for down-regulating the expression level of angiotensin receptor gene and its application

Abstract

The invention provides a plant lactobacillus IOB602 for down-regulating the expression level of angiotensin receptor gene and its application, which relates to the technical field of microorganisms. The classification of plant lactobacillus IOB602 is named plant lactobacillus Lactiplantibacillus plants It was deposited in the General Microbiology Center of China Microorganism Culture Collection Administration on June 29, 2018, abbreviated as CGMCC, with the deposit address at No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number is CGMCC No.16021. It down-regulates the gene expression level of angiotensin II receptor type 1 AT1R, activates the PI3K / AKT1 / eNOS / NO signaling pathway and inhibits the activity of angiotensin converting enzyme, thereby enhancing vasodilation and lowering blood pressure.

Description

Technical Field

[0001] The invention belongs to the technical field of microorganisms, and particularly relates to a Lactobacillus plantarum IOB602 for down-regulating the expression level of angiotensin receptor genes and an application thereof. Background Art

[0002] Hypertension is the main risk factor for cardiovascular disease in China and the leading cause of all-cause mortality and disability worldwide. The occurrence and development of hypertension is a complex pathophysiological process, which is the result of the imbalance of multiple blood pressure regulation mechanisms.

[0003] At present, a large number of studies have shown that the pathogenesis of hypertension mainly includes abnormal vascular function, nervous system regulation, renin-angiotensin-aldosterone system (RAAS), renal reabsorption disorder, kinin-kallikrein system, etc. Among them, overactivation of the RAAS system is an important mechanism causing vasoconstriction, inflammation and vascular remodeling. RAAS is an important regulatory system for cardiovascular and renal function, and plays an important role in the body's blood pressure control and circulating blood volume regulation. It is composed of multiple active substances such as angiotensinogen (AGT), angiotensin converting enzyme (ACE), angiotensin Ι (Ang Ι), angiotensin Ⅱ (Ang Ⅱ), Ang Ⅱ receptor (Ang Ⅱ receptor, ATR) and aldosterone (Aldosterone, ALD), and participates in the short-term and long-term regulation of blood pressure by controlling blood volume and peripheral resistance.

[0004] At present, drugs that directly inhibit the activity of AngⅡ (such as angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists) are already commonly used antihypertensive drugs in clinical practice. However, due to the feedback regulation mechanism of the body, simply inhibiting the activity of AngⅡ cannot completely block its pressor effect. For example, when angiotensin-converting enzyme inhibitors are used, renin secretion will increase compensatorily, thereby restoring the production of AngⅡ to a certain extent.

[0005] Reducing the expression of angiotensin II receptor type 1 (AT1R) gene and intervening at the receptor level can bypass this feedback regulation mechanism to a certain extent and more directly block the pressor effect of Ang II. Reducing the expression of AT1R gene will reduce the number of AT1R on the cell surface. In this way, even if Ang II exists in the body, due to the reduction of its target receptors, the series of pressor reactions caused by Ang II (such as vasoconstriction, increased aldosterone secretion, etc.) will be weakened, thereby helping to lower blood pressure.

[0006] At present, the main technologies for reducing AT1R gene expression include antisense oligonucleotide technology, RNA interference technology, drug intervention or gene editing technology. Antisense oligonucleotide technology has stability problems and is easily degraded by nucleases. Its delivery is difficult and requires the use of specific carriers. Non-specific binding may also occur. RNA interference technology has off-target effects, and the duration of gene expression inhibition is short. Effective delivery also faces challenges. Drug intervention will bring side effects, and different patients have individual differences in response. Long-term use may lead to drug resistance. Gene editing technology has a high risk of off-target, ethical disputes and complex technology.

[0007] Probiotics are generally considered to be relatively safe, with fewer side effects, and can be taken orally, with high patient compliance. Probiotics often have other beneficial effects such as regulating intestinal flora, which have a positive impact on intestinal health, the immune system, etc.

[0008] However, the research on probiotics reducing AT1R gene expression is still in its preliminary stage, and its effectiveness still needs further in-depth research and verification. Summary of the invention

[0009] In view of the technical problems existing in the prior art, the present invention aims to provide a Lactobacillus plantarum IOB602 for down-regulating the expression level of angiotensin receptor gene and its application.

[0010] One of the purposes of the present invention is to provide a plant lactobacillus IOB602 that downregulates the expression level of angiotensin receptor gene. The classification name of the plant lactobacillus IOB602 is plant lactobacillus Lactiplantibacillus plantarum It was deposited on June 29, 2018 in the General Microbiology Center of China Microorganism Culture Collection, referred to as CGMCC. The deposit address is No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number is CGMCC No.16021.

[0011] Preferably, the Lactobacillus plantarum IOB602 has at least one of the following functions:

[0012] (1) Down-regulate the gene expression level of angiotensin II receptor type 1 AT1R;

[0013] (2) Activate the PI3K / AKT1 / eNOS / NO signaling pathway;

[0014] (3) Inhibit the activity of angiotensin-converting enzyme.

[0015] Preferably, the Lactobacillus plantarum IOB602 can be used to prepare Lactobacillus plantarum IOB602 powder and Lactobacillus plantarum IOB602 postbiotics.

[0016] Preferably, the preparation method of the Lactobacillus plantarum IOB602 powder and the Lactobacillus plantarum IOB602 postbiotics comprises:

[0017] The plant lactobacillus plantarum IOB602 in the cryopreservation tube is inoculated into the seed culture medium, and placed at 35-37°C for culture, and the activation time is 22-24 hours to obtain an activated bacterial solution, and the activated bacterial solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 18-20 hours to obtain a primary seed solution; the primary seed solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 16-18 hours to obtain a secondary seed solution; the secondary seed solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 16-18 hours to obtain a secondary seed solution; -3% inoculation amount is inoculated into the fermentation medium, and cultured in a 35-37°C incubator for 14-16 hours to obtain a culture solution; the culture solution is centrifuged at 4-6°C and 4000-6000rpm / min for 20-30min, the supernatant is discarded, and the precipitate after centrifugation is collected, which is placed at -80~-60°C for pre-freezing for 2-3h, and then freeze-dried, the drying temperature is set to -60~-40°C, and the drying time is 24-36h to obtain Lactobacillus plantarum IOB602 bacterial powder;

[0018] The centrifuged precipitate is sterilized at 80-95°C for 30-50 min, and then placed at -80~-60°C for pre-freezing for 2-3 h, and then freeze-dried. The drying temperature is set to -60~-40°C and the drying time is 24-36 h to obtain the postbiotics of Lactobacillus plantarum IOB602.

[0019] Preferably, the viable bacterial count of the Lactobacillus plantarum IOB602 powder is 1×10 9 CFU / g-7.0×10 11 CFU / g.

[0020] Preferably, the Lactobacillus plantarum IOB602 can be used to prepare a medicine for down-regulating the expression level of angiotensin receptor gene.

[0021] Preferably, the Lactobacillus plantarum IOB602 can be used to prepare health products for maintaining healthy blood pressure levels.

[0022] Beneficial effects of the present invention:

[0023] The present invention provides a plant lactobacillus IOB602 for down-regulating the gene expression level of angiotensin receptor. The bacterium down-regulates the gene expression level of angiotensin II receptor type 1 (AT1R), reduces the number of AT1R, and thus reduces the adverse effects of angiotensin II binding thereto, such as vasoconstriction, increased aldosterone secretion, water and sodium retention, etc., which promotes blood pressure increase. After PI3K is activated, AKT1 is further activated, and AKT1 promotes the activity of endothelial nitric oxide synthase (eNOS). eNOS catalyzes the production of nitric oxide (NO). NO has a strong vasodilating effect, can dilate blood vessels, and reduce peripheral resistance. Angiotensin converting enzyme can convert angiotensin I into angiotensin II with a strong vasoconstrictive effect. Inhibiting the activity of the enzyme can reduce the generation of angiotensin II and reduce the binding of angiotensin II to its receptor.

[0024] When the AT1R gene expression level is downregulated, the binding of angiotensin II to the receptor is reduced, which directly weakens the vasoconstriction effect. On the other hand, since the inhibitory effect of angiotensin II on the PI3K / AKT1 / eNOS / NO signaling pathway is weakened, it may indirectly promote the activation of the signaling pathway. The activated signaling pathway produces more NO, further enhancing the vasodilation effect and jointly lowering blood pressure.

[0025] In addition, Lactobacillus plantarum IOB602 can also reduce oxidative stress caused by hypertension, reduce the inflammatory response of hypertensive rats, alleviate myocardial hypertrophy and renal fibrosis in hypertensive rats, and improve the damage of renal tissue atrophy and apoptosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the ACE inhibition rate of bacterial powder group and postbiotic group;

[0027] Figure 2 It is the ACE inhibition rate of the supernatant of bacterial liquid with molecular weight of 10-30 kDa, 3-10 kDa and <3 kDa after ultrafiltration;

[0028] Figure 3 The effects of Lactobacillus plantarum IOB602 and postbiotics on cardiac indexes in hypertensive rats;

[0029] Figure 4 The effects of Lactobacillus plantarum IOB602 and postbiotics on renal indices in hypertensive rats;

[0030] Figure 5 The effects of Lactobacillus plantarum IOB602 and postbiotics on the gene expression level of AT1R in rat hearts;

[0031] Figure 6 The effects of Lactobacillus plantarum IOB602 and postbiotics on AngⅡ activity in rat plasma;

[0032] Figure 7 is the gene expression level of PI3K in rat heart;

[0033] Figure 8 is the gene expression level of AKT1 in rat heart;

[0034] Fig. 9 is the activity of nitric oxide synthase in rat plasma;

[0035] Fig.10 is the concentration of nitric oxide in rat plasma;

[0036] Fig.11 is the superoxide dismutase content in rat plasma;

[0037] Fig.12 is the plasma glutathione content of rats;

[0038] Fig.13 is the malondialdehyde content in rat plasma;

[0039] Fig.14 is the activity of IL-6 in rat plasma;

[0040] Fig.15 is the activity of IL-1β in rat plasma;

[0041] Fig.16 This is the pathological morphology of the thoracic aorta in hypertensive rats;

[0042] Fig.17 The pathological morphology of heart tissue in hypertensive rats;

[0043] Fig.18 This is the pathological morphology of renal tissue in hypertensive rats.

[0044] The Lactobacillus plantarum IOB602 used in the present invention is classified and named as Lactobacillus plantarum Lactiplantibacillus plantarum It was deposited on June 29, 2018 in the General Microbiology Center of China Microorganism Culture Collection, referred to as CGMCC. The deposit address is No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number is CGMCC No.16021. DETAILED DESCRIPTION

[0045] The invention provides an application of Lactobacillus plantarum IOB602 in preparing a medicine for down-regulating the expression level of angiotensin receptor genes.

[0046] In a preferred embodiment of the present invention, the Lactobacillus plantarum IOB602 has at least one of the following functions:

[0047] (1) Down-regulate the gene expression level of angiotensin II receptor type 1 AT1R;

[0048] (2) Activate the PI3K / AKT1 / eNOS / NO signaling pathway;

[0049] (3) Inhibit the activity of angiotensin-converting enzyme.

[0050] In a preferred embodiment of the present invention, the drug for down-regulating the expression level of angiotensin receptor gene comprises Lactobacillus plantarum IOB602 powder and Lactobacillus plantarum IOB602 postbiotics.

[0051] In a preferred embodiment of the present invention, the preparation method of the Lactobacillus plantarum IOB602 powder and the Lactobacillus plantarum IOB602 postbiotics comprises:

[0052] The plant lactobacillus plantarum IOB602 in the cryopreservation tube is inoculated into the seed culture medium, and placed at 35-37°C for culture, and the activation time is 22-24 hours to obtain an activated bacterial solution, and the activated bacterial solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 18-20 hours to obtain a primary seed solution; the primary seed solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 16-18 hours to obtain a secondary seed solution; the secondary seed solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 16-18 hours to obtain a secondary seed solution; -3% inoculation amount is inoculated into the fermentation medium, and cultured in a 35-37°C incubator for 14-16 hours to obtain a culture solution; the culture solution is centrifuged at 4-6°C and 4000-6000rpm / min for 20-30min, the supernatant is discarded, and the precipitate after centrifugation is collected, which is placed at -80~-60°C for pre-freezing for 2-3h, and then freeze-dried, the drying temperature is set to -60~-40°C, and the drying time is 24-36h to obtain Lactobacillus plantarum IOB602 bacterial powder;

[0053] The centrifuged precipitate is sterilized at 80-95°C for 30-50 min, and then placed at -80~-60°C for pre-freezing for 2-3 h, and then freeze-dried. The drying temperature is set to -60~-40°C and the drying time is 24-36 h to obtain the postbiotics of Lactobacillus plantarum IOB602.

[0054] In a preferred embodiment of the present invention, the viable bacterial count of the Lactobacillus plantarum IOB602 powder is 1×10 9 CFU / g-7.0×10 11 CFU / g.

[0055] In a preferred embodiment of the present invention, the Lactobacillus plantarum IOB602 can be used to prepare health products for maintaining healthy blood pressure levels.

[0056] Example 1

[0057] Preparation method of Lactobacillus plantarum IOB602 powder and postbiotics

[0058] 1. Process

[0059] The plant lactobacillus plantarum IOB602 in the cryopreservation tube is inoculated into the seed culture medium, and placed at 35-37°C for culture, and the activation time is 22-24 hours to obtain an activated bacterial solution, and the activated bacterial solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 18-20 hours to obtain a primary seed solution; the primary seed solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 16-18 hours to obtain a secondary seed solution; the secondary seed solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 16-18 hours to obtain a secondary seed solution; -3% inoculation amount is inoculated into the fermentation medium, and cultured in a 35-37°C incubator for 14-16 hours to obtain a culture solution; the culture solution is centrifuged at 4-6°C and 4000-6000rpm / min for 20-30min, the supernatant is discarded, and the precipitate after centrifugation is collected, which is placed at -80~-60°C for pre-freezing for 2-3h, and then freeze-dried, the drying temperature is set to -60~-40°C, and the drying time is 24-36h to obtain Lactobacillus plantarum IOB602 bacterial powder;

[0060] The centrifuged precipitate is sterilized at 80-95°C for 30-50 min, and then placed at -80~-60°C for pre-freezing for 2-3 h, and then freeze-dried. The drying temperature is set to -60~-40°C and the drying time is 24-36 h to obtain the postbiotics of Lactobacillus plantarum IOB602.

[0061] 2. Activity detection

[0062] The activity of Lactobacillus plantarum IOB602 powder was tested according to the method of "GB4789.35-2024 National Food Safety Standard - Food Microbiology Test - Lactic Acid Bacteria Test". The final test result was 6.5×10 11 CFU / g.

[0063] Example 2

[0064] Inhibitory effects of Lactobacillus plantarum IOB602 powder and postbiotics on angiotensin converting enzyme (ACE)

[0065] The specific steps for determining the ACE inhibition rate are as follows:

[0066] (1) Preparation of working solution: Dissolve N-(3-(2-furanyl) acryloyl)-L-phenylalanyl-glycyl-glycine (FAPGG) in Tris-HCl solution (pH=7.5), and dissolve ACE in sterile enzyme-free water to prepare 0.88 mmol / L and 0.25 U / ml FAPGG and ACE working solutions, respectively.

[0067] (2) Sample preparation: Lactobacillus plantarum IOB602 was activated twice, inoculated into MRS liquid medium and cultured at 37°C for 24 h, centrifuged at 7000 g for 10 min, and the supernatant was obtained for use as the bacterial powder group sample. Using the gradient counting method, the same concentration of postbiotics was taken from the bacterial liquid and dissolved in liquid MRS medium for use as the postbiotic group sample.

[0068] (3) Add 150 μL of FAPGG working solution to a transparent 96-well plate, preheat at 37°C for 5 min, add 10 μL of ACE working solution and sample, shake evenly and immediately measure the OD340 nm. Incubate at 37°C for 15 min and measure the OD340 nm again. Treat the no-enzyme control group B (ACE working solution was replaced by sterile enzyme-free water), enzyme solution control group C (sample was replaced by Tris-HCl), and blank control group D (ACE working solution and sample were replaced by sterile enzyme-free water and Tris-HCl) in the same way. The specific reaction system is shown in Table 1.

[0069] Table 1 ACE inhibition rate in vitro detection reaction system

[0070]

[0071] (4) Calculation of in vitro ACE inhibition rate

[0072] ACE inhibition rate = {[(C1-C2)-(D1-D2)]-[(A1-A2)-(B1-B2)]} / [(C1-C2)-(D1-D2)]×100%

[0073] Where: A1—OD340 nm of sample group A before incubation for 15 min

[0074] A2—OD340 nm after incubation of sample group A for 15 min

[0075] B1—OD340 nm before incubation for 15 min in the control group B without enzyme

[0076] B2—OD340 nm after incubation of the control group B without enzyme water for 15 min

[0077] C1—OD340 nm before incubation of enzyme solution control group C for 15 min

[0078] C2—OD340 nm after incubation of enzyme solution control group C for 15 min

[0079] D1—blank control group D OD340 nm before incubation for 15 min

[0080] D2—OD340 nm of the blank control group D after incubation for 15 min.

[0081] The ACE inhibition rate of IOB602 bacterial supernatant and postbiotics was determined. The results are as follows Figure 1 Among them, the ACE inhibition rate of postbiotics was the highest, at 82.21%, which was higher than that of the bacterial supernatant at 80.92%, but not significantly higher, indicating that the ACE inhibitory active substances in the bacterial supernatant and postbiotics mainly came from the metabolites of IOB602.

[0082] After ultrafiltration of the bacterial supernatant, three fractions were obtained: >10 kDa, 3-10 kDa, and <3 kDa. Figure 2 As shown. After ultrafiltration, the ACE inhibition rate of molecular weight <3 kDa was significantly higher than that of >10 kDa and 3~10 kDa (P<0.001), which may be due to the higher biological activity of small molecule peptides. However, since the ACE inhibition rates of the three components were all high, the subsequent experiments were still carried out with the whole bacterial solution.

[0083] Example 3

[0084] Establishment and treatment of hypertensive rat model

[0085] 50 rats were randomly selected as the normal group after 7 days of adaptive feeding, and the rest were used as the hypertension modeling group. The modeling group drank 400 mg / L of L-NAME daily, and the normal group drank normal water daily, and the modeling was continued for 8 weeks. Four weeks after the modeling, the rats with successful modeling were selected according to the NO value measured by orbital blood sampling and randomly divided into four groups: model group, captopril group, IOB602 probiotic group and postbiotic group. The captopril group was gavaged with 10 mg / kg of captopril daily, and the probiotic group was gavaged with 1×10 IOB602 bacterial powder daily. 9 CFU / kg, postbiotic group was gavaged with IOB602 postbiotics 1×10 9 CFU / kg, the model group was gavaged with the same dose of normal saline. The chemical name of L-NAME is Nω-nitro-L-arginine methyl ester.

[0086] After eight weeks, rats in each group were weighed, eyeballs were removed for blood collection, and rats were killed by cervical dislocation. The thoracic aorta, kidneys, and heart were removed. The blood was placed in a heparin anticoagulation tube and centrifuged at 4°C, 4000 r / min for 10 min, and plasma samples were taken for later use. The heart and kidney weights were quickly weighed, and then the left ventricle of the heart, the kidney part, and the tail thoracic aorta were removed and immersed in 4% paraformaldehyde solution for fixation. Tissue sections were made, and the prepared sections were stained with HE, observed under an optical microscope, and photographed. The remaining heart part was rinsed with cold sterile saline, quickly frozen with liquid nitrogen, and stored in a -80°C refrigerator.

[0087] Example 4

[0088] Effects of Lactobacillus plantarum IOB602 and postbiotics on organ indexes in hypertensive rats

[0089] After 4 weeks of administration, the rats were weighed and their hearts and kidneys were weighed to calculate the cardiac index and renal index. Figure 3 As shown in the figure, the cardiac index of the rats in the model group was significantly higher than that of the rats in the normal group (P<0.001), indicating that the model group may have increased ventricular wall tension due to compensatory heart pressure increase, which in turn led to myocardial hypertrophy. According to the calculation formula, reduction rate (%) = (experimental group - model group) / experimental group, the IOB602 probiotic group, postbiotic group and captopril group significantly reduced the heart / body weight values ​​of rats by 14.1%, 8.7% and 10.1%, respectively, indicating that they have a certain protective effect on L-NAME-induced hypertensive rats. Figure 4 As shown in the data, the renal index of rats in the model group was significantly lower than that in the normal group (P<0.05). After the protection of probiotics and postbiotics, the damage of L-NAME to renal tissue fibrosis and atrophy and apoptosis was improved to a certain extent. The renal index of rats in the probiotics and postbiotics groups increased by 8.6% and 12.3%, respectively.

[0090] Example 5

[0091] Lactobacillus plantarum IOB602 and postbiotics reduce AT1R gene expression in rat myocardial tissue

[0092] Rat myocardial tissue stored at -80°C was placed in a sterile enzyme-free centrifuge tube, and total RNA was extracted according to the Trizol method. cDNA was synthesized by reverse transcription, and amplification reaction was performed according to the instructions of the fluorescent quantitative PCR kit. The conditions were: 95°C pre-denaturation for 2 min, 95°C denaturation for 10 s, 60°C annealing for 30 min, 40 cycles, 95°C extension for 1 min, 55°C extension for 1 min, and 95°C extension for 15 s. The relative expression of the target gene was calculated. The primer sequences used are shown in Table 2.

[0093] Table 2 Primer sequences

[0094]

[0095] Depend on Figure 5 It was found that the gene expression level of AT1R in the model group rats was upregulated by 300.88% compared with that in the normal group; after the intervention of IOB602 probiotics and postbiotics, the AT1R gene was significantly downregulated by 63.4% and 60%, respectively, compared with the model group.

[0096] Example 6

[0097] Effects of Lactobacillus plantarum IOB602 and postbiotics on AngⅡ activity in plasma of hypertensive rats

[0098] The experiment used the plasma collected in Example 3 to determine the rat angiotensin II (Ang II) in the plasma of each group of rats. The detection steps were carried out according to the instructions of the rat angiotensin II (Ang II) ELISA kit.

[0099] like Figure 6 As shown in the data, the AngⅡ activity in the model group was significantly increased to 215.14 ng / ml compared with the normal group (P<0.001). Compared with the model group, the AngⅡ activity in the IOB602 probiotics, postbiotics and captopril groups decreased by 30%, 35% and 32%, respectively. Among them, the postbiotic group decreased most significantly (P<0.001), from 215.14 ng / ml to 139.44 ng / ml.

[0100] Example 7

[0101] Effects of Lactobacillus plantarum IOB602 and postbiotics on PI3K / AKT1 / eNOS / NO signaling pathway

[0102] The gene expression level test protocol of PI3K and AKT1 in the PI3K / AKT1 / eNOS / NO signaling pathway was carried out according to the steps of Example 5, wherein the primers used are shown in Table 3. The eNOS activity and NO content detection experiments used the plasma collected in Example 3, and the detection steps were carried out according to the kit instructions.

[0103] Table 3 Primer sequences

[0104]

[0105] like Figure 7 and Figure 8As shown in the data, the gene expression levels of PI3K and AKT1 in the heart of rats in the model group decreased to varying degrees compared with those in the normal group, decreasing by 33.8% and 12.9%, respectively; after the intervention of IOB602 probiotics and postbiotics, compared with the model group, the PI3K gene was significantly upregulated, at 192.4% and 177.3%, respectively; the AKT1 gene was also significantly upregulated to varying degrees, at 280.4% and 155.5%, respectively (P<0.001).

[0106] like Fig. 9 and Fig.10 As shown, the plasma eNOS and NO concentrations of rats in the model group were significantly reduced by 42.7% and 62.7% compared with those in the normal group (P<0.001). The plasma eNOS and NO concentrations increased after intervention with IOB602 probiotics and postbiotics, which were statistically significant compared with the model group. The plasma eNOS and NO concentrations increased by 37% and 58.3% after intervention with IOB602 probiotics, and increased by 56% and 128.6% after intervention with postbiotics (P<0.05, P<0.01, P<0.001).

[0107] Example 8

[0108] Effects of Lactobacillus plantarum IOB602 and postbiotics on oxidative stress-related indices in hypertensive rats

[0109] like Fig.11 , Fig.12 and Fig.13 As shown in the results, after rats ingested L-NAME, the levels of plasma superoxide dismutase (SOD) and plasma glutathione (GSH) were significantly reduced, and the level of plasma malondialdehyde (MDA) was significantly increased (P<0.001), indicating that long-term reduction of NO generation and utilization would lead to oxidative stress in individuals. Compared with the model group, the levels of SOD and GSH in the probiotic group increased significantly (P<0.001), from 73.45 U / ml and 6.83 mg / L to 95.23 U / ml and 12.48 mg / L, an increase of 29.7% and 82.7%, respectively; those in the postbiotic group increased significantly to 112.4 U / ml and 15.87 mg / L (P<0.001), an increase of 53.1% and 132.4%, respectively. Compared with the model group, probiotics and postbiotics also significantly reduced the MDA content (P<0.001), from 17.79 nmol / ml to 9.08 nmol / ml and 7.95 nmol / ml, a decrease of 49% and 55.3%, respectively.

[0110] Example 9

[0111] Effects of Lactobacillus plantarum IOB602 and postbiotics on plasma inflammatory factors in hypertensive rats

[0112] The results of plasma IL-6 and IL-1β activity assays are as follows Fig.14 and Fig.15 The results showed that compared with the normal group, the activities of plasma IL-6 and IL-1β in the model group were significantly increased by 46% and 76% (P<0.001), indicating that L-NAME-induced hypertensive rats may cause the release of a large number of proinflammatory factors in the rats through oxidative stress or vascular endothelial dysfunction, induce the activation of inflammatory pathways, and then trigger inflammatory responses. The IOB602 probiotic group, postbiotic group and captopril group all effectively reduced the activities of plasma IL-6 and IL-1β in L-NAME-induced hypertensive rats, which was statistically significant compared with the model group. The IOB602 probiotic group reduced the activities of plasma IL-6 and IL-1β in hypertensive rats by 22% and 47%, the postbiotic group reduced the activities of plasma IL-6 and IL-1β in L-NAME-induced hypertensive rats by 32% and 48%, and the captopril group effectively reduced the activities of plasma IL-6 and IL-1β in L-NAME-induced hypertensive rats by 26% and 43% (P<0.001).

[0113] Example 10

[0114] Effects of Lactobacillus plantarum IOB602 and postbiotics on pathological morphology of organ tissues in hypertensive rats

[0115] The protective effects of Lactobacillus plantarum IOB602 probiotics and postbiotics on L-NAME-induced hypertensive rats were determined through various organ tissues of rats (including thoracic aorta, heart, and kidney). Fig.16 The pathological morphology of thoracic aorta tissue was as follows: in the normal control group, the intima was relatively smooth, the endothelial cells were relatively intact, and there was basically no deposit in the adventitia connective tissue; in the model control group, the thickness of the intima was uneven, severe hyperplasia was obviously observed in the intima, endothelial cells were swollen and ruptured, and cell hyperplasia was observed in the media smooth muscle; in the captopril group, lactic acid bacteria and postbiotic group, the arterial wall thickness was basically uniform, the intima was also relatively smooth, and the media smooth muscle cells were significantly improved. Fig.17 The pathological morphology of cardiac tissues was that the size of myocardial cells of rats in the normal control group was normal and arranged regularly; the size of myocardial cells of rats in the model control group was abnormal, with obvious tissue edema, disordered arrangement, and inflammatory cell infiltration, and myocardial fibers were thick and broken; after intervention in the IOB602 probiotics, postbiotics and captopril groups, the tightness of myocardial fibers was significantly improved, the arrangement was more regular, the degree of edema was significantly reduced, and the protective effect of postbiotics was significantly higher than that of probiotics and captopril. These results show that IOB602 probiotics and postbiotics have different degrees of improvement in pathological changes such as myocardial fibrosis, interstitial inflammation and myocardial hypertrophy. Fig.18Kidney sections showed that in the normal control group, the glomeruli composed of glomeruli and glomerular capsules were uniform in size, and the renal tubular structure connected to the glomeruli was clear. In the model control group, the glomerular capsule cavity was enlarged, the renal tubular lumen became larger, and the interstitial blood vessels were congested. Compared with the model group, the captopril group, IOB602 probiotics and postbiotics inhibited the damage of L-NAME to the kidney structure and played a certain protective role.

Claims

1. A Lactobacillus plantarum ( Lactiplantibacillus plantarum ) The use of IOB602 in the preparation of a drug for treating hypertension by downregulating the expression level of angiotensin II receptor type 1 gene, characterized in that: The deposit number of the Lactobacillus plantarum IOB602 is CGMCC No.16021.

2. The use according to claim 1, characterized in that The drug for treating hypertension by down-regulating the expression level of angiotensin II receptor type 1 gene comprises Lactobacillus plantarum IOB602 bacterial powder and / or Lactobacillus plantarum IOB602 postbiotics.

3. The use according to claim 2, characterized in that The preparation method of the Lactobacillus plantarum IOB602 powder and the Lactobacillus plantarum IOB602 postbiotics comprises: The plant lactobacillus plantarum IOB602 in the cryopreservation tube is inoculated into the seed culture medium, and placed at 35-37°C for culture, and the activation time is 22-24 hours to obtain an activated bacterial solution, and the activated bacterial solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 18-20 hours to obtain a primary seed solution; the primary seed solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 16-18 hours to obtain a secondary seed solution; the secondary seed solution is inoculated into the seed culture medium at an inoculation amount of 1-3%, and cultured in a 35-37°C incubator for 16-18 hours to obtain a secondary seed solution; -3% inoculation amount is inoculated into the fermentation medium, and cultured in a 35-37°C incubator for 14-16 hours to obtain a culture solution; the culture solution is centrifuged at 4-6°C and 4000-6000rpm / min for 20-30min, the supernatant is discarded, and the precipitate after centrifugation is collected, which is placed at -80~-60°C for pre-freezing for 2-3h, and then freeze-dried, the drying temperature is set to -60~-40°C, and the drying time is 24-36h to obtain Lactobacillus plantarum IOB602 bacterial powder; The centrifuged precipitate is sterilized at 80-95°C for 30-50 min, and then placed at -80~-60°C for pre-freezing for 2-3 h, and then freeze-dried. The drying temperature is set to -60~-40°C and the drying time is 24-36 h to obtain the postbiotics of Lactobacillus plantarum IOB602.

4. The use according to claim 2, characterized in that The viable bacterial count of the Lactobacillus plantarum IOB602 powder is 1×10 9 CFU / g-7.0×10 11 CFU / g.

5. An application of Lactobacillus plantarum IOB602 in preparing a health food for assisting in lowering blood pressure, characterized in that: The deposit number of the Lactobacillus plantarum IOB602 is CGMCC No.16021.

Images