BACKGROUND:In previous studies,glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by a double sintering method to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials that can maintain high transparency and high flexural strength.OBJECTIVE:To evaluate the in vitro biocompatibility of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials.METHODS:(1)Glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by double sintering to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia(or 5Y-PSZ ultra-translucent zirconia,3Y-TZP transparent zirconia)was placed in DMEM culture medium containing 10％fetal bovine serum for 12,24 and 72 hours,and the surface area ratio of culture medium to sample was 3 mL/cm2,and the 12-,24-and 72-hour material extracts were obtained.(2)After culturing mouse fibroblast L929 for 24 hours,the original culture medium was discarded and divided into 7 groups for culture:the control group was replaced with DMEM culture medium containing 10％fetal bovine serum by volume,and the other 6 groups were replaced with 24-hour extract of 3Y-TZP transparent zirconia,24-hour extract of 5Y-PSZ ultra-translucent zirconia,24-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,72-hour extract of 3Y-TZP transparent zirconia,72-hour extract of 5Y-PSZ ultra-translucent zirconia,and 72-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.After 1,3,and 5 days of culture,cell growth was observed under a microscope,and the cell proliferation rate was obtained by CCK-8 assay to determine cytotoxicity.(3)Human anticoagulated blood was mixed with 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,5Y-PSZ ultra-translucent zirconia,and 3Y-TZP transparent zirconia,and the hemolysis rate was detected after 0.5 hours.Human anticoagulated blood was mixed with 12-hour extract of 3Y-TZP transparent zirconia,12-hour extract of 5Y-PSZ ultra-translucent zirconia,and 12-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,and the hemolysis rate was detected after 0.5 hours.RESULTS AND CONCLUSION:(1)Under the microscope,it could be seen that the number of cells in each group increased with the extension of culture time,and the cell morphology of each experimental group was basically the same as that of the control group.The cytotoxicity grade of the 24-hour extract of 3Y-TZP transparent zirconia group on the first day of culture was grade 0,and the cytotoxicity grade of the other experimental groups at each time period was grade 1.(2)Neither the material nor the material extract caused obvious hemolytic reaction,and the hemolytic rate was less than 5％.(3)The results showed that 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia had no significant effect on the growth and proliferation of mouse fibroblasts L929,and did not cause hemolytic reaction with human blood,and had good in vitro biocompatibility.

OBJECTIVE To investigate the apoptosis-inducing effect of esculetin （Esc） on acute myeloid leukemia （AML） HL-60 cells by regulating the protein kinase B （AKT）/S-phase kinase-associated protein 2 （SKP2）/MutT homolog 1 （MTH1） pathway. METHODS AML HL-60 cells were randomly divided into control group （routine culture）， Esc low-concentration group （L-Esc group， 25 μmol/L Esc）， Esc medium-concentration group （M-Esc group， 50 μmol/L Esc）， Esc high-concentration group （H-Esc group， 100 μmol/L Esc）， and high-concentration of Esc+ SC79 （AKT agonist） group （100 μmol/L Esc+5 μmol/L SC79）. Cell proliferation in each group was detected by MTT assay and colony formation assay. The level of reactive oxygen species （ROS） in cells was measured by using the CM-H2DCFDA fluorescent probe. Cell apoptosis was analyzed by flow cytometry. Western blot assay was performed to detect the expression levels of apoptosis-related proteins [B-cell lymphoma 2 （Bcl-2）， Bcl-2-associated X protein （Bax）， cleaved caspase-3]， AKT/SKP2/MTH1 pathway-related proteins （p-AKT， AKT， SKP2， MTH1）， along with the upstream and downstream proteins of AKT phosphatidylinositol 3-kinase （PI3K）， cyclin-dependent kinase inhibitor 1 （P21） and cyclin-dependent kinase inhibitor 1B （P27）. RESULTS Compared with control group， the cell viability， colony number， and the phosphorylation levels of AKT and PI3K proteins as well as protein expressions of SKP2， MTH1 and Bcl-2 were significantly decreased （P＜0.05）， while ROS level， apoptosis rate， and the expression levels of Bax， cleaved caspase-3， P21 and P27 proteins were significantly increased （P＜0.05）. Moreover， the effects of Esc exhibited concentration-dependence （P＜0.05）. Compared with H-Esc group， above indexes of high-concentration of Esc+ SC79 group were reversed significantly （P＜0.05）. CONCLUSIONS Esc may promote massive ROS production and induce activation of apoptosis in HL-60 cells by inhibiting the AKT/SKP2/MTH1 pathway， thus inhibiting the proliferation of HL-60 cells.

BACKGROUND:In previous studies,glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by a double sintering method to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials that can maintain high transparency and high flexural strength.OBJECTIVE:To evaluate the in vitro biocompatibility of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials.METHODS:(1)Glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by double sintering to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia(or 5Y-PSZ ultra-translucent zirconia,3Y-TZP transparent zirconia)was placed in DMEM culture medium containing 10％fetal bovine serum for 12,24 and 72 hours,and the surface area ratio of culture medium to sample was 3 mL/cm2,and the 12-,24-and 72-hour material extracts were obtained.(2)After culturing mouse fibroblast L929 for 24 hours,the original culture medium was discarded and divided into 7 groups for culture:the control group was replaced with DMEM culture medium containing 10％fetal bovine serum by volume,and the other 6 groups were replaced with 24-hour extract of 3Y-TZP transparent zirconia,24-hour extract of 5Y-PSZ ultra-translucent zirconia,24-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,72-hour extract of 3Y-TZP transparent zirconia,72-hour extract of 5Y-PSZ ultra-translucent zirconia,and 72-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.After 1,3,and 5 days of culture,cell growth was observed under a microscope,and the cell proliferation rate was obtained by CCK-8 assay to determine cytotoxicity.(3)Human anticoagulated blood was mixed with 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,5Y-PSZ ultra-translucent zirconia,and 3Y-TZP transparent zirconia,and the hemolysis rate was detected after 0.5 hours.Human anticoagulated blood was mixed with 12-hour extract of 3Y-TZP transparent zirconia,12-hour extract of 5Y-PSZ ultra-translucent zirconia,and 12-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,and the hemolysis rate was detected after 0.5 hours.RESULTS AND CONCLUSION:(1)Under the microscope,it could be seen that the number of cells in each group increased with the extension of culture time,and the cell morphology of each experimental group was basically the same as that of the control group.The cytotoxicity grade of the 24-hour extract of 3Y-TZP transparent zirconia group on the first day of culture was grade 0,and the cytotoxicity grade of the other experimental groups at each time period was grade 1.(2)Neither the material nor the material extract caused obvious hemolytic reaction,and the hemolytic rate was less than 5％.(3)The results showed that 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia had no significant effect on the growth and proliferation of mouse fibroblasts L929,and did not cause hemolytic reaction with human blood,and had good in vitro biocompatibility.

Objective By simulating the etiology of abnormal uterine bleeding-ovulatory dysfunction(AUB-O)and establishing a rat model of abnormal uterine bleeding(AUB),this study aims to provide an experimental platform for investigating pathological mechanisms and developing therapeutic drugs for AUB.Methods After acclimation,24 adult(10-week-old)female SD rats were randomly divided into a normal control group(6 rats)and a model group(18 rats).The normal control group was housed in a barrier environment,while the model group underwent bilateral ovariectomy via dorsal approach in the same environment and rested for one week before starting to receive modeling drugs.In the model group,from Days 1 to 3 of modeling,each rat received a daily subcutaneous injection of 0.5 mg estradiol into the dorsal region.From Days 4 to 7,a daily subcutaneous injection of 5.0 mg progesterone was administered.On Day 6,rats received bilateral injections of 0.5 mL soybean oil per uterine cavity(total 1.0 mL)via the same dorsal surgical incision.On Day 8,mifepristone(10 mg/kg)was administered via oral gavage.The estrous cycle stage and its dynamic changes were continuously monitored during modeling.Uterine bleeding was recorded during the 48-hour observation period post-modeling.Serum and uterine tissue samples were collected from the model group at 0,12,24,36,and 48 h after mifepristone administration,while the normal control group was sampled at 36 h.The samples were subjected to HE staining,serum sex hormone ELISA,immunohistochemistry,TUNEL apoptosis staining,Western blotting,transcriptome sequencing,and bioinformatics analysis for comprehensive evaluation of the AUB rat model.Results The AUB rats exhibited uterine bleeding,endometrial detachment and injury,incomplete uterine restoration,inflammatory cell infiltration in the endometrium,enhanced tissue apoptosis,and structural damage of the stroma,glands,and vasculature.Compared with the normal control group,the levels of serum follicle-stimulating hormone(FSH),estradiol,and luteinizing hormone(LH)were significantly increased in the AUB rats(P＜0.05).The vascular density of the endometrium was significantly reduced(P＜0.05).The expression of vascular endothelial growth factor(VEGF)was qualitatively observed to be markedly enhanced at the site of endometrial detachment but significantly decreased around the stromal blood vessels(P＜0.01).Matrix metalloproteinase-9(MMP-9)expression was qualitatively observed to be strongly upregulated at the site of endometrial injury but significantly reduced in the non-detached stroma and glands(P＜0.01).Endometrial stromal cell apoptosis was significantly enhanced(P＜0.01).The expression levels of fibroblast growth factor 2(FGF2)and endothelin-1(ET-1)in uterine tissues were significantly decreased(P＜0.05).After comparing the transcriptome sequencing results of uterine tissues between AUB and normal rats,a total of 4 723 differentially expressed genes were identified,including 2 191 up-regulated genes and 2 532 down-regulated genes.KEGG enrichment analysis revealed that these differentially expressed genes were significantly enriched in pathways related to inflammation,immune apoptosis,cell signal transduction,proliferation and differentiation,and muscle contraction,among others.Conclusion An AUB rat model can be successfully established using a sequential administration protocol of estrogen,progesterone,and mifepristone to simulate the etiology of AUB-O.In this model,endometrial injury is associated with inflammation and apoptosis,with pathological manifestations influenced by abnormal vasoconstriction and impaired endometrial regeneration.This rat model closely recapitulates pathological characteristics of non-structural AUB observed in clinical practice,making it a validated experimental platform for exploring the pathological mechanisms and therapeutic interventions of non-structural AUB.

AIM To investigate the protective effects of Shuangyi Qushi Tongluo Capsules(Shuangyi Capsules)on Dexamethasone(Dex)induced osteoporosis in mice.METHODS The C57BL/6J mice were randomly divided into the control group,the model group,the Xianling Gubao Capsules group(1.5 g/kg),and the low-dose,moderate-dose,and high-dose Shuangyi Capsules groups(0.6,1.2,and 2.4 g/kg).The mouse model of osteoporosis was induced by 8-week intraperitoneal injection of Dex sodium phosphate injection(5 mg/kg).The mice had their femur osteogenesis observed with hematoxylin and eosin(HE)staining and tartrate-resistant acid phosphatase(TRAP)staining;their serum alkaline phosphatase(ALP)and osteocalcin(BGP)activities detected by ELISA;their femoral mRNA expressions of Col-Ⅰ,OCN,and OPN detected by RT-qPCR;and their femoral protein expressions of OPG and RANKL detected by Western blot.Upon the MC3T3-E1 cells exposed to Dex and Shuangyi Capsules,their viability was evaluated by CCK-8 assay;their mineralization determined by alkaline phosphatase staining and alizarin red staining(ARS);and their intracellular ROS level detected using DCFH-DA probe.RESULTS Compared with the model group,Shuangyi Capsules groups demonstrated improved fracture of femoral trabeculae and reduced number of osteoclasts;increased serum ALP and BGP activities(P＜0.05,P＜0.01);increased femoral expressions of Col-Ⅰ mRNA and OPG protein(P＜0.05,P＜0.01);and decreased RANKL protein expression(P＜0.05).Compared with the MC3T3-E1 cells stimulated by Dex,those underwent further treatment of Shuangyi Capsules demonstrated increased cell viability and ALP activity(P＜0.05,P＜0.01);increased mineralization and calcium nodule formation;increased expressions of Col-Ⅰ,OCN,OPN mRNA and OPG protein(P＜0.05,P＜0.01);decreased RANKL protein expression(P＜0.05,P＜0.01);and reduced ROS levels.CONCLUSION Shuangyi Capsules ameliorate Dex-induced osteoporosis in mice by suppressing osteoclast overactivation,enhancing osteoblast activity,and stimulating bone formation through modulation of Col-Ⅰ,OCN,OPN mRNA and OPG/RANKL protein levels.

Aim To evaluate the role of the glucose transporter protein 1(GLUT1)-dependent glycolytic in the attenuation of oxygen-glucose deprivation-reoxygen-ation(OGD/R)injury in HK-2 cells by dexmedetomi-dine(Dex).Methods C57/BL6 mice were random-ly divided into three groups(n=6),namely,sham operation group(Sham group),renal ischemia reper-fusion group(I/R group)and Dex group(I/R+Dex group).Serum creatinine(Cr)and urea nitrogen(BUN)were measured,while the levels of key glyco-lytic enzymes HK2,PFKFB3 and GLUT1 were meas-ured.HK-2 cells were cultured and randomised into seven groups(n=6),which was treated with OGD/R,overexpression or interference with GLUT1,Dex and glycolysis inhibitor 2-DG.CCK-8 and LDH activi-ty were used to detect cellular damage.Glycolysis lev-els were detected by lactate and ECAR.The inflamma-tory level was reflected by qRT-PCR for IL-6 and TNF-α.qRT-PCR and Western blot were performed to de-tect the levels of GLUT1,HK2,and PFKFB3.Results Dex significantly ameliorated kidney injury and HK-2 cell injury(P＜0.05).Dex inhibited the OGD/R-induced rise in lactate and extracellular acidification rate(ECAR),as evidenced by suppression of the ex-pression of GLUT1,HK2 and PFKFB3(P＜0.05).In vitro experiments showed that GLUT1 knockdown sig-nificantly improved OGD/R-induced cellular damage.Lactate,ECAR,glycolysis-related mRNAs and pro-teins were inhibited by GLUT1 knockdown(P＜0.05).Significantly,there were no significant differ-ences in above indexes after Dex treatment based on GLUT1 knockdown.Overexpression of GLUT1 abroga-ted the protective effects of Dex,while reversing the inhibitory effects of Dex on the expression of GLUT1,HK2,and PFKFB3(P＜0.05).Conclusions Dexmedetomidine attenuates OGD/R induced injury in HK-2 cells by inhibiting GLUT1-dependent glycolysis.

Objective:To evaluate the clinical predictive value of SPECT myocardial perfusion imaging (MPI) in the occurrence of cardiac death in patients with chronic kidney disease (CKD).Methods:A retrospective follow-up was performed for 160 patients (109 males, 51 females; age: 68.5(61.0, 74.0) years) who underwent MPI in Beijing Anzhen Hospital, Capital Medical University between June 2017 and March 2024. The 17-segment 5-point method was used for image analysis to obtain the left ventricular myocardial perfusion and functional parameters. The patients were followed up for cardiac death, and divided into death group and survival group. Clinical data of those 2 groups were compare by χ2 test, the independent-sample t test or Mann-Whitney U test. Cox proportional hazards regression analysis was used to analyze the predictors related to cardiac death. The ROC curve was used to analyze the performance of predictors. Survival curves were obtained by the Kaplan-Meier method, and log-rank test was performed to compare the difference between 2 groups. Results:The follow-up time of 160 patients with CKD was 26.0(10.0, 46.5) months. Of 160 patients, 17 died and 143 survived. There were statistically significant differences in body mass index (BMI), previous myocardial infarction, previous revascularization, hypersensitive C-reactive protein (hs-CRP), positive MPI, left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), summed stress score (SSS), summed rest score (SRS) and summed difference score (SDS) between the death group and the survival group ( χ2 values: 4.58-16.13, t values: -2.34, -3.97, Z values: from -2.81 to 5.02, all P<0.05). Multivariate Cox regression analysis showed that SSS (hazard ratio ( HR)=1.153, 95% CI: 1.062-1.252, P=0.001) and hs-CRP ( HR=1.031, 95% CI: 1.004-1.058, P=0.023) were independent risk factors for cardiac death in patients with CKD. The optimal cut-off value of SSS for predicting cardiac death in those patients was determined to be 8 with the AUC of 0.815, and the incidence of cardiac death in the SSS ≥8 group was significantly higher than that in the SSS<8 group (33.3%(12/36) vs 4.0%(5/124); χ2 = 25.44, P<0.001). Conclusion:MPI is an important imaging method for the evaluation of cardiac death in patients with CKD, SSS and hs-CRP are important risk factors in predicting cardiac death in those patients.

Objective To explore the role and mechanism of RNA m6A methyltransferase Wilms'tumor 1-associated protein(WTAP)in epithelial-mesenchymal transition(EMT)of glioblastoma cells and its association with transcription factor JUNB.Methods(1)Based on the Cancer Genome Atlas(TCGA)and Genotype-Tissue Expression(GTEx)databases,the expression levels of transforming growth factor β(TGF-β),WTAP,and JUNB in glioblastoma multiforme(GBM)and normal brain tissues were analyzed,as well as their diagnostic and prognostic values for GBM.The correlation of TGF-β,WTAP,and JUNB with gliomas of different WHO grades was analyzed using the Chinese Glioma Genome Atlas(CGGA)database.Spearman correlation analysis was performed to assess the correlation between TGF-β and m6A methyltransferases.(2)An EMT model was established in human astrocytoma U87-MG cells through TGF-β1 induction.qRT-PCR and Western blotting were employed to detect the expression levels of WTAP,JUNB,matrix metalloproteinase 2(MMP2),and N-cadherin.The migration capacity of U87-MG cells was evaluated by wound-healing and Transwell assays.An m6A RNA methylation quantification kit(colorimetric)was used to detect RNA m6A methylation modification levels.A stable cell line with low expression of WTAP was constructed to investigate the effects of WTAP knockdown on the migration ability of U87-MG cells,as well as the expression of JUNB.(3)A protein-protein interaction network was constructed using STRING database and GeneMANIA database,followed by gene ontology(GO)and KEGG pathway enrichment analyses to explore the biological processes,molecular functions,cellular components,and signaling pathways potentially involved in TGF-β/WTAP/JUNB.Gene set enrichment analysis(GSEA)was performed on JUNB-related genes to investigate their potential downstream signaling pathways.Results(1)The expression levels of TGF-β,WTAP,and JUNB were significantly higher in GBM(P<0.001),positively correlated with WHO grades of glioma(P<0.001).Glioma patients with high expression of all three genes had shorter overall and disease-free survival(P<0.001).Spearman analysis showed that the expression of TGF-β in GBM was positively correlated with WTAP(r=0.175,P=0.023),but no significant correlation with other m6A methyltransferases(P>0.05).(2)After TGF-β1 treatment,the level of m6A methylation modification of total RNA in U87-MG cells significantly increased(P<0.001).Wound-healing assay and Transwell assay results showed that the migration ability of U87-MG cells was significantly increased after TGF-β1 treatment(P<0.01),while WTAP knockdown significantly reduced the migration ability of U87-MG cells(P<0.01).qRT-PCR and Western blotting results showed that the mRNA and protein expression levels of WTAP,N-Cadherin,MMP2,and JUNB in U87-MG cells were significantly increased after 48 h of TGF-β1 induction(P<0.001),while WTAP knockdown significantly reduced the mRNA and protein expression of JUNB(P<0.001).(3)The TGF-β/WTAP/JUNB-related protein-protein interaction network was constructed,which was primary involved in mRNA modification and EMT.GSEA results showed that JUNB-related signaling pathways were closely associated with glioma malignant progression.Conclusions TGF-β,WTAP,and JUNB are all associated with GBM malignant progression and poor patient prognosis.TGF-β may enhance total RNA m6A modification by promoting the expression of m6A methyltransferase WTAP,and WTAP subsquentaly upregulates transcription factor JUNB,thereby promoting EMT and malignant progression of GBM.

Objective:To evaluate the clinical predictive value of SPECT myocardial perfusion imaging (MPI) in the occurrence of cardiac death in patients with chronic kidney disease (CKD).Methods:A retrospective follow-up was performed for 160 patients (109 males, 51 females; age: 68.5(61.0, 74.0) years) who underwent MPI in Beijing Anzhen Hospital, Capital Medical University between June 2017 and March 2024. The 17-segment 5-point method was used for image analysis to obtain the left ventricular myocardial perfusion and functional parameters. The patients were followed up for cardiac death, and divided into death group and survival group. Clinical data of those 2 groups were compare by χ2 test, the independent-sample t test or Mann-Whitney U test. Cox proportional hazards regression analysis was used to analyze the predictors related to cardiac death. The ROC curve was used to analyze the performance of predictors. Survival curves were obtained by the Kaplan-Meier method, and log-rank test was performed to compare the difference between 2 groups. Results:The follow-up time of 160 patients with CKD was 26.0(10.0, 46.5) months. Of 160 patients, 17 died and 143 survived. There were statistically significant differences in body mass index (BMI), previous myocardial infarction, previous revascularization, hypersensitive C-reactive protein (hs-CRP), positive MPI, left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), summed stress score (SSS), summed rest score (SRS) and summed difference score (SDS) between the death group and the survival group ( χ2 values: 4.58-16.13, t values: -2.34, -3.97, Z values: from -2.81 to 5.02, all P<0.05). Multivariate Cox regression analysis showed that SSS (hazard ratio ( HR)=1.153, 95% CI: 1.062-1.252, P=0.001) and hs-CRP ( HR=1.031, 95% CI: 1.004-1.058, P=0.023) were independent risk factors for cardiac death in patients with CKD. The optimal cut-off value of SSS for predicting cardiac death in those patients was determined to be 8 with the AUC of 0.815, and the incidence of cardiac death in the SSS ≥8 group was significantly higher than that in the SSS<8 group (33.3%(12/36) vs 4.0%(5/124); χ2 = 25.44, P<0.001). Conclusion:MPI is an important imaging method for the evaluation of cardiac death in patients with CKD, SSS and hs-CRP are important risk factors in predicting cardiac death in those patients.

Objective By simulating the etiology of abnormal uterine bleeding-ovulatory dysfunction(AUB-O)and establishing a rat model of abnormal uterine bleeding(AUB),this study aims to provide an experimental platform for investigating pathological mechanisms and developing therapeutic drugs for AUB.Methods After acclimation,24 adult(10-week-old)female SD rats were randomly divided into a normal control group(6 rats)and a model group(18 rats).The normal control group was housed in a barrier environment,while the model group underwent bilateral ovariectomy via dorsal approach in the same environment and rested for one week before starting to receive modeling drugs.In the model group,from Days 1 to 3 of modeling,each rat received a daily subcutaneous injection of 0.5 mg estradiol into the dorsal region.From Days 4 to 7,a daily subcutaneous injection of 5.0 mg progesterone was administered.On Day 6,rats received bilateral injections of 0.5 mL soybean oil per uterine cavity(total 1.0 mL)via the same dorsal surgical incision.On Day 8,mifepristone(10 mg/kg)was administered via oral gavage.The estrous cycle stage and its dynamic changes were continuously monitored during modeling.Uterine bleeding was recorded during the 48-hour observation period post-modeling.Serum and uterine tissue samples were collected from the model group at 0,12,24,36,and 48 h after mifepristone administration,while the normal control group was sampled at 36 h.The samples were subjected to HE staining,serum sex hormone ELISA,immunohistochemistry,TUNEL apoptosis staining,Western blotting,transcriptome sequencing,and bioinformatics analysis for comprehensive evaluation of the AUB rat model.Results The AUB rats exhibited uterine bleeding,endometrial detachment and injury,incomplete uterine restoration,inflammatory cell infiltration in the endometrium,enhanced tissue apoptosis,and structural damage of the stroma,glands,and vasculature.Compared with the normal control group,the levels of serum follicle-stimulating hormone(FSH),estradiol,and luteinizing hormone(LH)were significantly increased in the AUB rats(P＜0.05).The vascular density of the endometrium was significantly reduced(P＜0.05).The expression of vascular endothelial growth factor(VEGF)was qualitatively observed to be markedly enhanced at the site of endometrial detachment but significantly decreased around the stromal blood vessels(P＜0.01).Matrix metalloproteinase-9(MMP-9)expression was qualitatively observed to be strongly upregulated at the site of endometrial injury but significantly reduced in the non-detached stroma and glands(P＜0.01).Endometrial stromal cell apoptosis was significantly enhanced(P＜0.01).The expression levels of fibroblast growth factor 2(FGF2)and endothelin-1(ET-1)in uterine tissues were significantly decreased(P＜0.05).After comparing the transcriptome sequencing results of uterine tissues between AUB and normal rats,a total of 4 723 differentially expressed genes were identified,including 2 191 up-regulated genes and 2 532 down-regulated genes.KEGG enrichment analysis revealed that these differentially expressed genes were significantly enriched in pathways related to inflammation,immune apoptosis,cell signal transduction,proliferation and differentiation,and muscle contraction,among others.Conclusion An AUB rat model can be successfully established using a sequential administration protocol of estrogen,progesterone,and mifepristone to simulate the etiology of AUB-O.In this model,endometrial injury is associated with inflammation and apoptosis,with pathological manifestations influenced by abnormal vasoconstriction and impaired endometrial regeneration.This rat model closely recapitulates pathological characteristics of non-structural AUB observed in clinical practice,making it a validated experimental platform for exploring the pathological mechanisms and therapeutic interventions of non-structural AUB.