Bifidobacterium adolescentis for reducing the risk of metabolic disorders associated with low estrogen levels and application thereof

Abstract

The application discloses a strain of Bifidobacterium adolescentis for reducing the risk of related metabolic disorders caused by low estrogen levels and an application thereof, and belongs to the technical field of microorganisms. The Bifidobacterium adolescentis CCFM1507 provided by the application can increase the estrogen level in serum of ovariectomized rats, increase the expression amount of CYP19 and ERa in adrenal gland tissue, and effectively inhibit the levels of increased IL-10 and TNF-alpha and decreased IL-4 in serum. The Bifidobacterium adolescentis CCFM1507 significantly reduces triglyceride (TG) and cholinesterase (CHE) in serum, relieves dyslipidemia, and increases the content of glutamine in serum. The Bifidobacterium adolescentis CCFM1507 is a food safety strain, and can be used for preparing food, functional food or medicine, and has a wide application prospect.

Description

Technical Field

[0001] This invention relates to a strain of Bifidobacterium adolescentis that reduces the risk of metabolic disorders caused by low estrogen levels and its applications, belonging to the field of microbiology. Background Technology

[0002] With an aging population, the prevalence of postmenopausal metabolic syndrome, including cardiovascular disease and cognitive impairment caused by decreased estrogen levels, is rising, severely impacting quality of life and posing a significant threat to health. The likelihood of developing postmenopausal metabolic syndrome increases with age and the decline in estrogen levels during menopause, especially after age 50. Currently, estrogen replacement therapy can alleviate postmenopausal metabolic syndrome, thereby reducing the risk of its development; however, it raises concerns about its potential to increase the risk of breast cancer and thrombosis, requiring rigorous evaluation and monitoring. Furthermore, estrogen replacement therapy can stimulate the rise in estrogen levels, making its application controversial. Dietary supplements such as soy isoflavones and terpene polysaccharides can improve postmenopausal metabolic syndrome through natural estrogen-like effects or antioxidant mechanisms, exhibiting high safety but slow onset of action. The gut microbiota is recognized as a key regulator of host endocrine metabolism, and interventions such as fecal microbiota transplantation, antibiotics, probiotics, and prebiotics provide feasible methods for restoring metabolic homeostasis. Probiotics are live, non-pathogenic microorganisms used to improve gut microbiota balance and gut metabolites. They can promote host health by reshaping the gut microbiota ecosystem and regulating its metabolites. Increasing evidence suggests that probiotics have the potential to regulate estrogen levels and alleviate postmenopausal metabolic syndrome. However, current probiotic research and studies generally suffer from insufficient functional targeting of strains. While common commercially available probiotics such as Bifidobacterium or Lactobacillus have some probiotic potential, most strains have not been screened and validated targeting estrogen metabolism, and their intervention effects on hormone metabolism lack clear evidence. Currently, only a very few strains, such as Lactobacillus gasseri CCFM1255, have shown some ability to regulate estrogen metabolism in studies. However, research on these functional strains remains fragmented, and their ability to alleviate estrogen metabolism-related metabolic disorders and obesity is limited. Therefore, there is an urgent need to develop new strains that can effectively intervene in estrogen disorders. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a strain of Bifidobacterium adolescentis that can effectively reduce the risk of metabolic disorders caused by low estrogen levels, and to provide related applications of the strain.

[0004] This invention provides a strain of Bifidobacterium adolescentis (Bifidobacterium adolescentis) Bifidobacterium adolescentisThe described Bifidobacterium adolescentis was deposited at the Guangdong Provincial Center for Microbial Culture Collection on June 6, 2025, with accession number GDMCCNo: 66475. (CCFM1507)

[0005] In one embodiment, the *Bifidobacterium adolescentis* was derived from fecal samples of women of childbearing age in Wuxi City, Jiangsu Province. Sequencing analysis of this strain, followed by nucleic acid sequence alignment using NCBI Standard Nucleotide BLAST, showed a 100.00% similarity to the nucleic acid sequence of *Bifidobacterium adolescentis*. The strain was thus identified as *Bifidobacterium adolescentis* and named *Bifidobacterium adolescentis*. Bifidobacterium adolescentis ) CCFM1507.

[0006] In one embodiment, the Bifidobacterium adolescentis (… Bifidobacterium adolescentis The CCFM1507 has the following characteristics: (1) It can significantly reduce the levels of IL-10 and TNF-α in serum.

[0007] (2) It can significantly increase the levels of IL-4 and cholinesterase in serum.

[0008] (3) It can significantly reduce the concentration of triglycerides in the serum of ovariectomized rats.

[0009] (4) Increase the level of estrogen in mammalian serum.

[0010] The present invention also provides a product containing the aforementioned Bifidobacterium adolescentis ( Bifidobacterium adolescentis The composition of CCFM1507.

[0011] In one embodiment, the composition includes, but is not limited to, microbial preparations.

[0012] In one embodiment, the Bifidobacterium adolescentis (… Bifidobacterium adolescentis The addition amount of CCFM1507 in microbial preparations shall not be less than 1×10⁻⁶. 8 CFU / g or 1×10 8 CFU / mL.

[0013] In one embodiment, the microbial preparation is a solid or liquid preparation.

[0014] In one embodiment, the microbial preparation is the Bifidobacterium adolescentis (… Bifidobacterium of a young man The powder obtained by drying the bacterial solution of CCFM1507.

[0015] In one embodiment, the drying includes, but is not limited to, vacuum freeze drying.

[0016] This invention also provides the above-mentioned Bifidobacterium adolescentis ( Bifidobacterium adolescentis The use of CCFM1507, or the above-mentioned microbial preparations, in the preparation of drugs to alleviate estrogen metabolism disorders.

[0017] In one embodiment, the estrogen metabolism disorder includes a decline in estrogen levels due to menopause.

[0018] In one embodiment, the product contains Bifidobacterium adolescentis (… Bifidobacterium of a young man The addition amount of CCFM1507 should not be less than 1×10⁻⁶. 8 CFU / g or 1×10 8 CFU / mL.

[0019] This invention also provides a medicine for alleviating estrogen metabolism disorder-related diseases and / or obesity, the product containing the aforementioned Bifidobacterium adolescentis (…). Bifidobacterium adolescentis ) CCFM1507.

[0020] In one embodiment, the drug contains *Bifidobacterium adolescentis* (…). Bifidobacterium of a young man The addition amount of CCFM1507 should not be less than 1×10⁻⁶. 8 CFU / g or 1×10 8 CFU / mL.

[0021] The present invention also provides the aforementioned Bifidobacterium adolescentis ( Bifidobacterium adolescentis The application of CCFM1507 in the preparation of products that alleviate obesity, including but not limited to one or more of the following functions: controlling body fat and maintaining healthy blood lipid levels.

[0022] The present invention also provides a product containing the aforementioned Bifidobacterium adolescentis CCFM1507.

[0023] In one embodiment, the product is food, medicine, or health product.

[0024] In one embodiment, the food is prepared using Bifidobacterium adolescentis (Bifidobacterium adolescentis). Bifidobacterium of a young man Dairy products, soy products, or fruit and vegetable products produced using CCFM1507 or the fermentation agent of the above-mentioned microbial preparations.

[0025] In one embodiment, the dairy products include fermented milk, flavored fermented milk, fermented milk beverages, cream, cheese, milk-containing beverages, or milk powder; the soy products include soy milk and soy milk powder; and the fruit and vegetable products include fruit and vegetable products made from at least one of cabbage, white radish, cucumber, beet, yellow peach, or bayberry products.

[0026] In one embodiment, the food is a fermented food, including solid food, liquid food, or semi-solid food.

[0027] In one embodiment, the food contains the aforementioned Bifidobacterium adolescentis (Bifidobacterium adolescentis). Bifidobacterium of a young man CCFM1507, or beverages or snacks containing the above-mentioned microbial preparations.

[0028] In one embodiment, the drug contains the aforementioned Bifidobacterium adolescentis (…). Bifidobacterium of a young man CCFM1507, as well as drug carriers and / or pharmaceutical excipients.

[0029] In one embodiment, the carrier includes one or more of the following commonly used in medicine: fillers, adhesives, wetting agents, disintegrants, lubricants, and flavoring agents.

[0030] In one embodiment, the dosage form of the medicine is granules, capsules, tablets, pills, or oral liquid.

[0031] The present invention also provides the above-mentioned Bifidobacterium adolescentis ( Bifidobacterium adolescentis Application of CCFM1507 in the preparation of pharmaceuticals or functional foods having at least one of the following functions: (a) Increases serum estradiol levels in mammals; (b) Increase the expression of CYP19A1 and ERα in mammalian adrenal tissue; (c) Reduces serum triglycerides (TG) in mammals; (d) Reduces serum IL-10 and TNF-α in mammals; (e) Increases IL-4 and cholinesterase (CHE) in mammalian serum; (f) Increase the level of glutamine in mammalian serum.

[0032] Beneficial effects The Bifidobacterium adolescentis GDMCC No: 66475 screened in this invention has a significant effect in alleviating or treating estrogen-related metabolic disorders and obesity, specifically including: (1) Significantly increased serum estradiol in ovariectomized rats and increased the expression levels of CYP19A1 and ERα in adrenal tissue; (2) Significantly reduced serum triglycerides (TG) and cholinesterase (CHE) in ovariectomized rats; (3) Improves the inflammatory state in rats; The *Bifidobacterium adolescentis* CCFM1507 of this invention exhibits superior efficacy in reducing the risk of metabolic disorders associated with low estrogen levels. Compared to the model group, it significantly increases serum glutamine (Gln) levels by 61.92%, helping to reduce the risk of metabolic disorders such as obesity, Cushing's syndrome, and fatty liver. Compared to estrogen drugs, it also shows more pronounced effects on peripheral blood estrogen, total cholesterol (TC), glucose (Glu), and short-chain fatty acids. Compared to normalized GDMCC NO: 62305, after intervention with *Bifidobacterium adolescentis* CCFM1507, serum estrogen and adrenal estrogen receptor ERα in mammalian adrenal glands significantly increased by 21.86% and 11.27%, respectively, while pro-inflammatory factors IL-6 and TNF-α significantly decreased by 10.55% and 20.00%, respectively, and serum triglycerides (TG) significantly decreased by 11.31%.

[0033] The strains of this invention can be used to prepare drugs that alleviate or treat estrogen-related metabolic disorders, and can also be used to prepare health products or foods that help control body fat and maintain healthy blood lipid levels, showing great application potential.

[0034] Preservation of biological materials Bifidobacterium adolescentis ( Bifidobacterium adolescentis CCFM1507, its taxonomic name is: Bifidobacterium adolescentis It was deposited on June 6, 2025 at the Guangdong Provincial Center for Microbial Culture Collection, with accession number GDMCC No: 66475. The deposit address is 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, Guangdong Institute of Microbiology. Attached Figure Description

[0035] Figure 1 Bifidobacterium adolescentis ( Bifidobacterium adolescentis Effects of CCFM1507 strain on serum estrogen levels in ovariectomized rats.

[0036] Figure 2 This is a schematic diagram showing the changes in CYP19A1 and ERα in the adrenal tissue of ovariectomized rats after intervention with Bifidobacterium adolescentis strain CCFM1507.

[0037] Figure 3 Bifidobacterium adolescentis ( Bifidobacterium adolescentis Effects of CCFM1507 strain on serum triglycerides (TG) in ovariectomized rats.

[0038] Figure 4 Bifidobacterium adolescentis ( Bifidobacterium adolescentisEffects of CCFM1507 strain on inflammatory factors in the serum of ovariectomized rats.

[0039] Figure 5 Bifidobacterium adolescentis ( Bifidobacterium adolescentis ) Schematic diagram of changes in serum cholinesterase (CHE) in ovariectomized rats after intervention with CCFM1507 strain.

[0040] Figure 6 Bifidobacterium adolescentis ( Bifidobacterium adolescentis ) Schematic diagram of changes in serum glutamine (Gln) in ovariectomized rats after intervention with CCFM1507 strain. Detailed Implementation

[0041] To make the above-mentioned objectives, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to specific examples.

[0042] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0043] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments. To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to specific examples.

[0044] The female SD rats used in the following examples were purchased from Spiford (Beijing) Biotechnology Co., Ltd.

[0045] The GDMCC NO:62035 strain involved in the following examples has been disclosed in the patent application document with publication number CN115584331A.

[0046] The culture media involved in the following examples are as follows: MRS liquid culture medium: 10g beef extract; 10g tryptone; 5g yeast extract; 20g glucose; 5g anhydrous sodium acetate; 0.1g MgSO4·7H2O; 0.05g MnSO4·H2O; 2g diammonium citrate; 2.6g K2HPO4·3H2O; 1mL Tween 80; 0.8g L-cysteine ​​hydrochloride; adjust pH to 6.8±0.2; bring volume to 1L. Autoclave at 115℃ for 20min.

[0047] MRS solid medium: 2% agar powder is added to the MRS liquid medium.

[0048] MRS liquid medium with mass percentage (0.05%-0.1%) cysteine: Add 0.08% cysteine ​​hydrochloride to the MRS liquid medium.

[0049] The preparation of Bifidobacterium adolescentis suspension involved in the following examples Bifidobacterium adolescentis was inoculated into MRS solid medium and cultured at 37°C for 72 h to obtain single colonies. The prepared single colonies were then inoculated into MRS liquid medium and cultured at 37°C for 24 h to activate them. After activation for three generations, the bacterial culture was inoculated into 1 L of MRS liquid medium at an inoculum size of 2% (v / v). After shaking and mixing, the culture was incubated at 37°C for 20 h in an anaerobic incubator. After centrifugation at 8000 g / min and 4°C for 15 min, the supernatant was removed, and the culture was washed three times with sterile physiological saline containing 0.05%-0.1% L-cysteine ​​hydrochloride. After centrifugation under the same conditions and removal of supernatant, the culture was resuspended in 60% glycerol to obtain the bacterial culture before gavage. The culture was then stored in a refrigerator for later use.

[0050] Before conducting animal experiments, the bacterial solution was taken out of the refrigerator, centrifuged at 6000 r / min for 5 min, washed 3 times with sterile physiological saline, resuspended in physiological saline, shaken evenly, and the number of viable bacteria at the beginning and after one week of storage was determined by plate pour method.

[0051] The results showed that the initial viable count was 3.42 × 10⁻⁶. 9 CFU / mL, viable bacterial count after 1 week was 2.88 × 10⁻⁶. 9 The CFU / mL value did not change in magnitude, indicating that freezing the bacterial culture would not affect the experiment and it can be used for animal experiments.

[0052] The detection methods involved in the following embodiments are as follows: The expression levels of CYP19A1 and ERα were detected as follows: The expression levels of CYP19A1 and ERα genes were determined using real-time quantitative polymerase chain reaction (qRT-PCR). First, RNA was extracted from fresh tissue. The specific method is as follows: 0.2 g of fresh adrenal tissue obtained from mouse dissection was repeatedly ground in a mortar (180℃, 4 h high-temperature enzyme inactivation) with liquid nitrogen. Then, 1 mL of TrizoL reagent was added to the mortar, and grinding continued until the liquid was basically clear. The mixture was then collected into a 1.5 mL enzyme-free centrifuge tube and allowed to stand at room temperature for 15 min. 200 μL of chloroform solution was added to the centrifuge tube, and the mixture was gently shaken for 15 s. The mixture was allowed to stand at room temperature for 10 min, and then centrifuged at 4 ℃ and 12000 r / min for 15 min. 600 μL of the colorless upper aqueous phase was transferred to another enzyme-free centrifuge tube, and 500 μL of isopropanol was added. Invert the tube to mix thoroughly, let stand at room temperature for 10 min, then centrifuge at 12000 r / min for 10 min at 4℃. Discard the supernatant, leaving the white precipitate formed at the bottom of the centrifuge tube containing RNA. Add 1 mL of 75% ethanol solution prepared with DEPC water, vortex to resuspend, centrifuge at 7500 r / min for 5 min at 4℃, discard the supernatant, and allow to evaporate and dry at room temperature. Add 30 μL of RNase-free water to the dried RNA. After the RNA dissolves, determine the RNA concentration and purity using Nanodrop, and assess the RNA quality by agarose gel electrophoresis. Using the extracted total RNA as a template, reverse transcribe cDNA according to the instructions of the HiScript III All-in-one RT SuperMix Perfect for qPCR Reverse Transcription Kit from Novizan Biotechnology Co., Ltd., and store at -20℃. Primers for rat CYP19A1 and ERα protein genes and the internal reference gene β-Actin gene are shown in Table 1.

[0053] Table 1. Sequences of rat CYP11A1 protein gene and internal reference β-actin primers

[0054] qRT-PCR reaction system and conditions: PCR amplification was performed using the Bio-Rad® CFX96™ Real-Time PCR instrument, and the fluorescence signal was read.

[0055] The c-kit gene qRT-PCR reaction system is as follows:

[0056] The c-kit gene qRT-PCR reaction conditions were: 95℃ for 30s; 95℃ for 10s, 60℃ for 30s, for a total of 40 cycles. The β-Actin gene was used as an internal control gene, and the results were analyzed using CFX96Manager software.

[0057] The method for detecting the concentration of short-chain fatty acids in serum involved in the following examples is as follows: The serum collected before the end of the experiment was frozen at -80°C. The specific method is as follows: Take 100 µL of serum sample into a 2 mL EP tube and add 300 µL of pre-chilled methanol to precipitate proteins. Vortex for 30 s, then incubate the sample at -20°C to improve protein precipitation. After 2 h, remove the sample and centrifuge at 4°C, 4000 rpm for 20 min. Pass the supernatant through a 0.22 µm organic filter membrane. Collect the filtered solution and transfer it to a sample vial for analysis. Prepare a standard curve by diluting the amino acid standard with a mobile phase mixture (20% A + 80% B) as needed. All solutions should be stored at -20°C and brought to room temperature before use.

[0058] Amino acids were detected using a Thermo Fisher Scientific ItiMate U-3000 ultra-high performance liquid chromatography (UPLC) system combined with a high-resolution Q-Exactive mass spectrometer. A BEH Amide column (2.1 × 100 mm, 1.7 µm) was used for separation of substances in the sample, with the column temperature set to 40 °C. The mobile phase consisted of 10 mM ammonium formate (A) and an aqueous solution containing 0.15% formate and acetonitrile (Vacetonitrile:Vwater = 90:10) (B). The sample injection volume was 2 µL. Full scan parameters in positive ion mode were: scan range 70–300 m / z; scan time 25 min; mass resolution 70,000; AGC target: 3e6; maximum IT value: 200 ms. Ion source settings were as follows: sheath gas 60 psi, auxiliary gas 35 psi, capillary temperature 550 °C, auxiliary gas heater temperature 350 °C.

[0059] Example 1: Bifidobacterium adolescentis ( Bifidobacterium adolescentis Separation of CCFM1507 1. Isolation and screening of Bifidobacterium strains: (1) Fecal samples were collected from women of childbearing age in Wuxi City, Jiangsu Province using a disposable sterile fecal collection device. The fecal samples were enriched in an anaerobic incubator (N2:CO2:H2=80:10:10) in MRS liquid medium containing 5~10 g / L fructooligosaccharides and 0.5~1 g / L cysteine. Single colonies were selected for purification culture.

[0060] 2. Molecular biological identification of Bifidobacteria (1) Take 1 mL of the bacterial cells screened in step 1 and activated for 3 generations (cultured for 12-48 h) for bacterial identification, centrifuge at 6000 r / min for 3 min, discard the supernatant to obtain bacterial cells.

[0061] (2) After adding 1 mL of sterile water and washing the bacterial cells by blowing, centrifuge at 10000 r / min for 1 min, discard the supernatant to obtain the bacterial cells, add 500 μL of sterile water to resuspend them, and use them as a template for bacterial culture.

[0062] (3) 16S rDNA PCR system: The bacterial 16S rDNA PCR reaction system in 20 µL contained: 27F, 0.5 µL; 1492R, 0.5 µL; Taq enzyme, 1 µL; template, 1 µL; ddH2O, 8 µL.

[0063] PCR conditions: 94°C for 5 min; 94°C for 30 s; 55°C for 30 s; 72°C for 2 min; 72°C for 10 min; step2-430×; 12°C for 2 min.

[0064] (4) Prepare 1% agarose gel, then mix the PCR product with 10000× Loading buffer, load 2µL, run at 120V for 30 min, and then perform gel imaging. (5) The PCR product of 16S rDNA was sequenced and analyzed. The sequencing result is shown in SEQ ID NO.1. The obtained sequence results were searched and compared for similarity in GenBank using BLAST. The sequencing results were selected, and the results showed that the strain was Bifidobacterium adolescentis. It was named Bifidobacterium adolescentis. Bifidobacterium adolescentis CCFM1507, 60% (v / v) glycerol, store at -80℃ for later use.

[0065] Example 2: Bifidobacterium adolescentis ( Bifidobacterium adolescentis CCFM1507 increases estrogen levels (1) Preparation of Bifidobacterium adolescentis CCFM1507 bacterial suspension After the Bifidobacterium adolescentis CCFM1507 strain was taken out of the -80℃ freezer, it was streaked on MRS solid medium and cultured at 37℃ for 48 h. Single colonies were picked and cultured on MRS liquid medium at 37℃ for 24 h to prepare seed culture. The prepared seed culture was inoculated into a new MRS liquid medium at an inoculation rate of 2% (v / v) and cultured at 37 °C for 24 h. The culture was repeated for one generation in the same manner to prepare the fermentation broth of Bifidobacterium adolescentis CCFM1507. The prepared Bifidobacterium adolescentis CCFM1507 fermentation broth was then centrifuged at 6000 r / min and 4℃ for 5 min, and then resuspended in 60% (v / v) glycerol to obtain a bacterial suspension. The suspension was stored in a refrigerator and centrifuged before being used in animal experiments, and then resuspended in physiological saline.

[0066] (2) Thirty healthy female SD rats aged 3 months were taken and acclimatized to the environment for 1 week, and then randomly divided into 5 groups: The rat groups included a sham-operated group, an ovariectomized model group, an estradiol group (E2, treatment group), a Bifidobacterium adolescentis intervention group (CCFM1507), and a Lactobacillus gasseri CCFM1255 group, with 6 rats in each group. Except for the sham-operated group, which only underwent ovarian exposure, all other groups had both ovaries removed. All rats rested for two weeks post-surgery. Then, starting on day 15 post-surgery, the sham-operated group and the ovariectomized model group were given physiological saline; the dose of the bacterial suspension administered by gavage was 5 × 10⁻⁶. 9 CFU / mL, 0.2 mL was administered by gavage starting at 9:00 AM every day; the estradiol drug group was given 28 μg / kg / day of estradiol per rat.

[0067] The grouping and treatment methods of the experimental animals are shown in Table 2.

[0068] Table 2 Grouping of experimental animals

[0069] Rats' body weight was recorded weekly at the start of the intervention. At the end of the experiment, fresh feces were collected and frozen at -80°C. At the end of the experiment, rats were fasted but allowed free water for 12 hours. After anesthesia with isoflurane, blood was collected from the abdominal aorta, and the rats were euthanized by cervical dislocation. Blood samples were centrifuged at 3500 r / min for 15 minutes, and the supernatant was collected and frozen at -80°C for blood parameter analysis. Adrenal gland tissue was quickly rinsed in pre-cooled physiological saline, and blood was collected. This blood was then flash-frozen in liquid nitrogen and transferred to -80°C for subsequent analysis of relevant parameters in the adrenal gland homogenate.

[0070] Serum estradiol levels were measured according to the kit instructions. Figure 1 As shown, compared with the ovariectomized rat model group, Bifidobacterium adolescentis CCFM1507 could increase the serum estradiol level, restoring the serum estradiol level in ovariectomized rats to a level superior to that of the sham-operated group (Bifidobacterium adolescentis CCFM1507 group: 440.81±47.49 ng / mL; sham-operated group: 406.29±25.19 ng / mL), an increase of 56.83% compared to the model group. Similarly, intervention with Lactobacillus gasseri CCFM1255 and estrogen could also restore the serum estradiol level in ovariectomized rats to some extent (Lactobacillus gasseri CCFM1255: 361.74±53.91 ng / mL; estrogen group: 377.39±35.13 ng / mL), increasing by 28.70% and 34.26% respectively. This indicates that intervention with Bifidobacterium adolescentis CCFM1507 can compensate for the decrease in estrogen levels caused by reduced ovarian function.

[0071] The above results indicate that Bifidobacterium adolescentis CCFM1507 can prevent and reduce the risk of metabolic diseases related to low estrogen levels.

[0072] Example 3: Bifidobacterium adolescentis CCFM1507 increases the expression levels of CYP19A1 and ERα genes in the adrenal tissue of ovariectomized rats. The grouping, modeling, and treatment methods for SD rats were the same as in Example 2. The expression levels of CYP19A1 and ERα genes were determined using real-time quantitative polymerase chain reaction (qRT-PCR).

[0073] CYP19A1 indirectly regulates estrogen levels by converting androgens produced by the ovary and peripheral tissues into estrogens. Abnormal activity of CYP19A1 can lead to an imbalance in the ratio of adrenal-derived androgens to estrogens, affecting reproductive and metabolic homeostasis. Figure 2 As shown, after gavage administration of Bifidobacterium adolescentis CCFM1507, the mRNA level of CYP19A1 in the adrenal tissue of ovariectomized rats was significantly increased to 2.01±0.511, which was superior to 1.92±0.50 in the Lactobacillus gasseri CCFM1255 group. The increase in CYP19A1 expression level indicates that the pathway of cholesterol to estrogen conversion is activated; Bifidobacterium adolescentis CCFM may be able to promote estrogen synthesis by increasing CYP19A1 expression in adrenal tissue.

[0074] On the other hand, Bifidobacterium adolescentis CCFM1507 significantly increased the mRNA level of ERα in the adrenal tissue of ovariectomized mice, reaching 2.27±0.28 compared to the ovariectomized group, and was also superior to the 2.04±0.42 in the Lactobacillus gasseri CCFM1255 group. Figure 2 An increase in ERα expression levels indicates that ERα is activated due to the influence of increased estrogen levels.

[0075] These results suggest that CCFM1507 may promote estradiol production and activate ERα by increasing the expression of CYP19A1 in the adrenal glands.

[0076] Example 4: Bifidobacterium adolescentis ( Bifidobacterium adolescentis CCFM1507 reduces triglyceride (TG) levels in mammalian serum. The experimental animals were grouped and treated in the same way as in Example 2. The serum triglyceride (TG) level was measured using a biochemical analyzer.

[0077] like Figure 3As shown, compared with the ovariectomized rat model group, *Bifidobacterium adolescentis* CCFM1507 reduced serum TG levels (0.24±0.02 mmol / L) by 31.42% compared to the ovariectomized group (0.35±0.08 mmol / L). Its ability to reduce serum triglycerides was superior to *Lactobacillus gasseri* CCFM1255 (0.28±0.06 mmol / L, reduction: 20.00%), and similar to the sham-operated group (0.25±0.02 mmol / L, reduction: 28.57%) and the estrogen group (0.24±0.02 mmol / L, reduction: 31.42%). The results of this example indicate that *Bifidobacterium adolescentis* CCFM1507 can reduce triglyceride (TG) levels in mice, which is beneficial in reducing the risk of estrogen withdrawal-related metabolic disorders.

[0078] Example 5: Bifidobacterium adolescentis ( Bifidobacterium adolescentis CCFM1507 alleviates inflammation caused by decreased estrogen levels. The experimental animals were grouped and treated in the same way as in Example 2, and the inflammatory factors in the serum were measured according to the kit instructions.

[0079] like Figure 4 As shown, compared with the ovariectomized rat model group, *Bifidobacterium adolescentis* CCFM1507 significantly reduced serum IL-6 and TNF-α levels in rats. After ovariectomy, IL-6 and TNF-α levels significantly increased, reaching 146.10±33.36 pg / mL and 173.40±17.80 pg / mL, respectively, while the IL-6 and TNF-α levels in the sham-operated group were 90.93±22.34 pg / mL and 97.98±7.01 pg / mL, respectively. *Bifidobacterium adolescentis* CCFM1507 intervention significantly reduced the levels of these inflammatory factors (IL-6: 99.20±4.39 pg / mL; TNF-α: 90.87±4.53 pg / mL). Meanwhile, Lactobacillus gasseri CCFM1255 and estradiol groups significantly reduced IL-6 (110.90±19.24 pg / mL) and TNF-α (113.60±15.87 pg / mL). At the same time, Bifidobacterium adolescentis CCFM1507 significantly increased the anti-inflammatory factor IL-4 (129.50±17.06 pg / mL), demonstrating superior anti-inflammatory ability compared to Lactobacillus gasseri CCFM1255 (128.30±7.571 pg / mL).

[0080] Example 6: Bifidobacterium adolescentis ( Bifidobacterium adolescentis CCFM1507 reduces cholinesterase (CHE) levels in mammalian serum. The experimental animals were grouped and treated in the same way as in Example 2. The serum cholinesterase (CHE) was measured using a biochemical analyzer.

[0081] like Figure 5 As shown, the serum cholinesterase level in ovariectomized rats (178.10±25.66 U / L) was lower than that in the sham-operated group (359.70±93.62 U / L). This indicates that ovariectomy alters serum cholinesterase (CHE) levels, and the presence of Bifidobacterium adolescentis CCFM1507 (286.20±83.48 U / L) and estradiol (350.20±72.71 U / L) significantly reversed this change, increasing serum cholinesterase concentration. However, Lactobacillus gasseri CCFM1255 (187.50±64.72 U / L) failed to increase CHE levels.

[0082] Example 7: Bifidobacterium adolescentis ( Bifidobacterium adolescentis CCFM1507 reduces the concentration of amino acids in mammalian serum. The grouping, modeling, and treatment methods for SD rats were the same as in Example 2.

[0083] After the experiment, the serum collected was analyzed using UPLC-Q-Exactive to determine the amino acid content in rat serum. The concentration of glutamine was then calculated.

[0084] The results are as follows Figure 6 As shown, serum glutamine levels in the ovariectomized rat group were decreased to some extent compared to the sham-operated group. Gavage administration of *Bifidobacterium adolescentis* CCFM1507 and *Lactobacillus gasseri* CCFM1255 reversed these changes and significantly increased serum glutamine levels, which were 9.57±0.214 ng / mL and 11.16±2.12 ng / mL, respectively, representing increases of 61.92% and 88.83% compared to the ovariectomized rats (5.91±0.79 μg / mL). P CCFM1507 =0.0073 and P CCFM1255 =0.0002). Meanwhile, the estradiol group (6.43±1.44 μg / mL) also regulated serum glutamine levels in ovariectomized rats, increasing it by only 8.80% compared to the ovariectomized group, a less effective effect than *Bifidobacterium adolescentis* CCFM1507 and *Lactobacillus gasseri* CCFM1255. Amino acid metabolism can induce insulin resistance in adipose tissue and reduce glucose uptake and triglyceride synthesis in tissues; therefore, *Bifidobacterium adolescentis* CCFM1507 plays a crucial role in increasing serum glutamine levels, potentially reducing the risk of metabolic disorders caused by low estrogen levels.

[0085] Example 7: Comparison of Bifidobacterium adolescentis CCFM1507 and Lactobacillus gasseri GDMCC NO:62395 The results of Bifidobacterium adolescentis CCFM1507 and GDMCC NO:62305 in animal experiments were normalized and compared with their model group (the modeling and animal treatment methods were the same as in Example 2, and the amino acid determination methods were exactly the same). The results are shown in Table 3.

[0086] Table 3 Comparison of results between CCFM1507 and GDMCC NO:62305

[0087] Note: The rate of change refers to the percentage improvement in effect of the CCFM1507 group compared to the GDMCC NO:62305 group.

[0088] The results show that, compared with GDMCC NO:62305, Bifidobacterium adolescentis CCFM1507 significantly increased estrogen levels in mammalian serum, and significantly increased ERα expression in adrenal tissue and serum glutamine levels. This suggests that the CCFM1507 strain may regulate abnormal lipid metabolism by altering the host's metabolic pathways through regulation of estrogen levels. These results indicate that the CCFM1507 strain plays a positive role in influencing host metabolism, particularly in regulating estrogen levels.

[0089] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. Bifidobacterium adolescentis ( Bifidobacterium adolescentis CCFM1507, characterized in that, The Bifidobacterium adolescentis was deposited at the Guangdong Provincial Center for Microbial Culture Collection on June 6, 2025, with accession number GDMCC No: 66475.

2. A composition containing the Bifidobacterium adolescentis as described in claim 1.

3. The composition according to claim 2, characterized in that, The composition is a microbial preparation containing the aforementioned Bifidobacterium adolescentis.

4. The composition according to claim 2, characterized in that, The composition is a food, medicine, or health product.

5. The composition according to claim 4, characterized in that, The drug contains the aforementioned Bifidobacterium adolescentis, as well as a drug carrier or pharmaceutical excipients.

6. The composition according to claim 4, characterized in that, The food product is a dairy product, soy product, or fruit and vegetable product containing the Bifidobacterium adolescentis.

7. The use of the Bifidobacterium adolescentis according to claim 1 in the preparation of a drug for relieving metabolic disorders caused by low estrogen levels.

8. The application according to claim 7, characterized in that, The relief of metabolic disorders caused by low estrogen levels includes maintaining healthy blood lipid levels.

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