1.Development and preliminary internal validation of a prediction model for brace treatment failure in adolescent idiopathic scoliosis using pretreatment and initial brace-fitting information
Ying MA ; Jun REN ; Shoujian WANG ; Xin ZHOU ; Tianxiang HE ; Lingjun KONG ; Min FANG
Chinese Journal of Rehabilitation Theory and Practice 2026;32(7):850-860
ObjectiveTo develop and preliminarily validate a prediction model for brace treatment failure risk in patients with adolescent idiopathic scoliosis (AIS), based on information obtained before brace treatment and during initial brace fitting. MethodsA total of 191 patients with AIS who initiated thoracolumbosacral orthosis treatment at Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine from March, 2015 to August, 2024 and had determinable outcomes were retrospectively included. Patients were divided according to a prespecified scheme into a training set (n = 133) and a validation set (n = 58). Brace treatment failure was defined as progression of the major-curve Cobb angle by ≥ 5° from baseline during follow-up or at brace weaning, or a final major-curve Cobb angle > 45°. Logistic regression, random forest, support vector machine with radial basis function kernel, and extreme gradient boosting (XGBoost) models were developed using routinely available clinical and radiographic variables before brace treatment and during initial brace fitting. Stratified five-fold cross-validation was used for hyperparameter tuning in the training set. Model performance was evaluated in the validation set using the area under the receiver operating characteristic curve (AUC), area under the precision-recall curve (AUPRC), Brier score, calibration curves, and decision curve analysis (DCA). SHapley Additive exPlanations (SHAP) was used to interpret the main explanatory model. ResultsIn cross-validation of the training set, both random forest and XGBoost showed good discriminative performance, with cross-validation-AUC values of 0.871 and 0.880, respectively. In the validation set, the AUC values of random forest and XGBoost were 0.888 and 0.899, the AUPRC values were 0.678 and 0.830, and the Brier scores were 0.086 and 0.076, respectively. Random forest was selected as the primary model for interpretation, with a calibration intercept of 0.091 and a calibration slope of 0.995. SHAP analysis indicated that the in-brace correction rate and the major-curve Cobb angle measured in the brace contributed most to the model predictions. ConclusionThe random forest model developed using routinely available pretreatment and initial-fitting variables shows preliminary predictive value for brace treatment failure risk in AIS, and may provide quantitative support for follow-up scheduling, brace-fit reassessment and early adherence-oriented management.
2.HIV-1 pretreatment drug resistance and molecular transmission network characteristics in Yubei District,Chongqing
Difei LI ; Ying XU ; Mao YE ; Xin HUANG ; Xuemei MA ; Yi JIN ; Songsong SUN ; Jinping XIONG ; Hui LIU ; Guohui WU
Chongqing Medicine 2025;54(3):719-724,730
Objective To analyze the characteristics of HIV-1 pretreatment drug resistance(PDR)and molecular transmission networks in Yubei District,Chongqing,providing evidence for targeted interventions.Methods Using a cross-sectional design,plasma samples were collected from HIV/AIDS patients receiving antiretroviral therapy(ART)in Yubei District from January 2022 to December 2023.Pol gene fragments were extracted and amplified for HIV-1 genotyping and drug resistance analysis.Molecular transmission networks were constructed based on genetic distance calculations.Results Among 478 HIV-1 pol sequences,eight geno-types were identified:with CRF07_BC(60.4%,289/478),CRF08_BC(15.5%,74/478),CRF01_AE(11.7%,56/478),and CRF85_BC(5.9%,28/478).The overall PDR rate was 6.3%(30/478),with resistance to nucleoside reverse transcriptase inhibitors(NRTIs)and non-nucleoside reverse transcriptase inhibitors(NNRTIs)at 1.7%(8/478)and 5.2%(25/478),respectively.No protease inhibitor(PI)resistance was de-tected.The molecular network included 177 cases(37.0%network entry rate),forming 53 clusters with 198 connections.Cluster sizes ranged from 2 to 17 nodes,and 75.3%(149/198)of connections were associated with five subdistricts/towns:Shuanglonghu Street,Huixing Street,Luoqi Town,Gulu Town,and Baoshenghu Street.Conclusion HIV-1 genotypes in Yubei District exhibit diversity and complexity,with moderate PDR prevalence.Regional clustering of transmission networks suggests the need for enhanced molecular surveil-lance and targeted interventions based on analytical findings.
3.Clinical characteristics of neonatal necrotizing enterocolitis and analysis of risk factors for early-onset children
Jing WANG ; Mingqi SHEN ; Rongxiu ZHENG ; Yue XIN ; Yunxia MA ; Ying ZHANG ; Dejing WU ; Dan LIU
International Journal of Pediatrics 2025;52(9):629-633
Objective:To explore the clinical characteristics of neonatal necrotizing enterocolitis(NEC)and analyze the risk factors for early-onset NEC.Methods:A total of 220 children with NEC admitted to the Department of Pediatrics,Tianjin Medical University General Hospital from January 1st,2018 to February 29th,2024 were retrospectively selected as the research objects. According to the time of onset,the early-onset group( n=120)and the late-onset group( n=100)were established,and the clinical characteristics of the two groups were compared. Another 150 cases of normal healthy newborns born in this hospital in the same period were selected as the control group,and the clinical data of the control group were collected. The clinical characteristics of the early-onset group and the control group were compared,and the risk factors of early-onset NEC were analyzed by multivariate Logistic regression. Results:Compared with the late-onset group,the early-onset group had fever[50.0%(60/120)vs. 40%(40/100), χ2=7.333, P=0.007],apnea[39.17%(47/120)vs. 28%(28/100), χ2=7.568, P=0.006],no rise in body temperature[56.67%(68/120)vs. 39%(39/100), χ2=6.815, P=0.009],abdominal distension[25%(30/120)vs. 40%(40/100), χ2=13.200, P<0.001],vomiting[30.83%(37/120)vs. 45%(45/100), χ2=12.797, P<0.001]was significantly different(all P<0.05);Multivariate Logistic regression analysis:weight<1 500 g( OR=5.871,95% CI:3.153~9.673, P<0.001),gestational age<30 weeks( OR=4.256,95% CI:2.641~7.896, P=0.007),hemodynamically significant patent ductus arteriosus(hs-PDA)( OR=3.113,95% CI:1.865~5.133, P=0.033),severe anemia( OR=3.057,95% CI:2.165~4.802, P=0.001),feeding intolerance( OR=4.215,95% CI:1.579~10.802, P=0.005),amniotic fluid pollution( OR=2.452,95% CI:1.579~3.111, P<0.001)were the independent risk factors for early-onset NEC(all P<0.05). Conclusion:Weight<1 500 g,gestational age<30 weeks,hs-PDA,severe anemia,feeding intolerance,and amniotic fluid contamination are independent risk factors for early-onset NEC. In clinical practice,more attention should be paid to these factors for disease prevention,early identification,and timely intervention in newborns to reduce the occurrence of NEC.
4.A photodynamic nanohybrid system reverses hypoxia and augment anti-primary and metastatic tumor efficacy of immunotherapy.
Haitao YUAN ; Xiaoxian WANG ; Xin SUN ; Di GU ; Jinan GUO ; Wei HUANG ; Jingbo MA ; Chunjin FU ; Da YIN ; Guohua ZENG ; Ying LONG ; Jigang WANG ; Zhijie LI
Acta Pharmaceutica Sinica B 2025;15(6):3243-3258
Photodynamic immunotherapy is a promising strategy for cancer treatment. However, the dysfunctional tumor vasculature results in tumor hypoxia and the low efficiency of drug delivery, which in turn restricts the anticancer effect of photodynamic immunotherapy. In this study, we designed photosensitive lipid nanoparticles. The synthesized PFBT@Rox Lip nanoparticles could produce type I/II reactive oxygen species (ROS) by electron or energy transfer through PFBT under light irradiation. Moreover, this nanosystem could alleviate tumor hypoxia and promote vascular normalization through Roxadustat. Upon irradiation with white light, the ROS produced by PFBT@Rox Lip nanoparticles in situ dysregulated calcium homeostasis and triggered endoplasmic reticulum stress, which further promoted the release of damage-associated molecular patterns, enhanced antigen presentation, and stimulated an effective adaptive immune response, ultimately priming the tumor microenvironment (TME) together with the hypoxia alleviation and vessel normalization by Roxadustat. Indeed, in vivo results indicated that PFBT@Rox Lip nanoparticles promoted M1 polarization of tumor-associated macrophages, recruited more natural killer cells, and augmented infiltration of T cells, thereby leading to efficient photodynamic immunotherapy and potentiating the anti-primary and metastatic tumor efficacy of PD-1 antibody. Collectively, photodynamic immunotherapy with PFBT@Rox Lip nanoparticles efficiently program TME through the induction of immunogenicity and oxygenation, and effectively suppress tumor growth through immunogenic cell death and enhanced anti-tumor immunity.
5.Effects and mechanisms of high-dose glucocorticoids on senescence, apoptosis, and osteogenic differentiation of bone marrow mesenchymal stem cells
Zhendong YING ; Changjun CHEN ; Dailing CHEN ; Qiuru WANG ; Qibin LIU ; Qingwei MA ; Lei ZHANG ; Pengde KANG ; Xin ZHAO
Chinese Journal of Orthopaedics 2025;45(18):1208-1216
Objective:To elucidate the molecular mechanisms through which high-dose dexamethasone exerts long-term effects on bone marrow mesenchymal stem cells (BMSCs), specifically its role in suppressing osteogenic differentiation, accelerating cellular senescence, triggering the senescence-associated secretory phenotype (SASP), and inducing apoptosis.Methods:Primary rat BMSCs were isolated and treated with high-dose dexamethasone (1×10 -4 mol/L) to establish the experimental group, while untreated cells served as the control. The gene and protein expression levels of osteogenic markers, bone alkaline phosphatase (bALP) and Runt-related transcription factor 2 (Runx2), were analyzed in both groups. Cellular senescence was evaluated using senescence-associated β-galactosidase (SA-β-gal) staining. The expression of senescence-related markers (P16 and P21), components of the senescence-associated secretory phenotype (SASP), including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and interferon (IFN)-γ, as well as apoptosis-related proteins (Bcl-2, Bax, and Cleaved-Caspase-3), and key factors of the Nrf2/HO-1 signaling pathway were assessed at both transcriptional and protein levels using qRT-PCR, immunofluorescence, and Western-blot analyses. These comprehensive evaluations aimed to determine the senescent state, apoptotic features, and alterations in osteogenic differentiation of BMSCs. Results:Following treatment with dexamethasone and subsequent withdrawal, both qRT-PCR and Western blot analyses indicated a significant reduction in the expression of the osteogenic markers bALP and Runx2 at both mRNA and protein levels. The proportion of SA-β-gal positive cells was markedly higher in the dexamethasone group (74.33%±6.89%) than in the control group (20.30%±1.57%, t=17.300, P<0.001). qRT-PCR analysis revealed upregulated mRNA expression of the senescence-related genes P16 and P21 after dexamethasone treatment, which was further supported at the protein level by immunofluorescence showing increased P21 expression. Western-blot results confirmed that protein expression levels of P16 and P21 were significantly elevated in the dexamethasone group (7.025±0.255 and 6.362±0.456, respectively) compared with the control group (1.016±0.115 and 0.816±0.172; both P<0.05). Furthermore, gene expression levels of the senescence-associated secretory phenotype (SASP) factors TNF-α and IL-1β were significantly increased (TNF-α: 3.539±0.599 vs. 0.742±0.095; IL-1β: 4.469±0.331 vs. 0.799±0.175; both P<0.05), and their protein expression was consistently upregulated as validated by Western-blot. Additionally, protein expression levels of TNF-α, IL-1β, and IFN-γ were significantly higher in the dexamethasone-treated group (3.476±0.932 vs. 0.945±0.095; 4.111±0.220 vs. 0.762±0.105; 2.155±0.240 vs. 0.656±0.104; all P<0.05).Western-blot analysis also demonstrated that protein expression of Nrf2 and HO-1 was significantly suppressed in the dexamethasone group (0.21±0.07 and 0.19±0.06, respectively) compared with the control group (1.13±0.15 and 0.92±0.21; P<0.05). Moreover, Western-blot analysis revealed that the expression levels of the pro-apoptotic proteins Bax and Cleaved-Caspase-3 were significantly up, regulated in the dexamethasone, treated BMSCs (Bax: 3.673±0.397 vs. 0.453±0.111; Cleaved-Caspase-3: 3.863±0.399 vs. 0.465±0.057), while the expression of the anti-apoptotic protein Bcl-2 was markedly down, regulated (0.959±0.073 vs. 2.126±0.195), with all differences being statistically significant ( P<0.05). Conclusions:High-dose dexamethasone treatment of BMSCs, followed by withdrawal of dexamethasone, induces cellular senescence and enhances the expression of the senescence-associated secretory phenotype (SASP) through suppression of the Nrf2/HO-1 signaling pathway. Concurrently, it promotes apoptosis by activating the mitochondrial apoptotic pathway, collectively leading to impaired osteogenic differentiation of BMSCs.
6.Clinical characteristics of 103 children with drug-induced hypersensitivity syndrome: a retrospective study
Lei JIAO ; Yuan LIANG ; Yang WANG ; Chunping SHEN ; Xin XIANG ; Zhe XU ; Yuanyuan XIAO ; Li LI ; Ying LIU ; Bin ZHANG ; Zigang XU ; Lin MA
Chinese Journal of Dermatology 2025;58(10):936-942
Objective:To investigate clinical characteristics, treatment approaches, and prognosis of drug-induced hypersensitivity syndrome (DIHS) in children.Methods:A retrospective analysis was performed on clinical data from pediatric inpatients with DIHS in Department of Dermatology, Beijing Children's Hospital from 2009 to 2023. The clinical data included demographic characteristics, clinical manifestations, laboratory findings, treatment regimens, and outcomes.Results:A total of 103 children with DIHS were included, comprising 54 males (52.4%) and 49 females (47.6%), with ages ( M [ Q1, Q3]) of 2.3 (1.2, 4.5) years. Primary causative drugs were antibiotics (52 cases, 45.2%), antiepileptic drugs (41 cases, 35.7%), and nonsteroidal anti-inflammatory drugs (19 cases, 16.5%), with a median latency period of 12 days. All patients presented with rashes, including 72 (69.9%) with maculopapular rashes, 69 (67.0%) with edema (including 46 with facial edema). Lip involvement occurred in 25 cases (24.3%), and mucosal involvement was noted in 11 cases (10.7%). Additionally, 102 (99.0%) patients had fever, and 79 (76.7%) presented with lymphadenectasis. Eosinophilia was present in 64 cases (62.1%). Among 84 patients tested for atypical lymphocytes, 51 (60.7%) showed elevated percentages of atypical lymphocytes. Liver involvement was noted in 94 cases (91.3%), followed by pulmonary involvement in 31 (30.1%), gastrointestinal symptoms in 25 (24.3%), cardiac involvement in 14 (13.6%), renal involvement in 10 (9.7%), and pancreatic involvement in 7 cases (6.8%). Among 82 patients tested for blood immunocytes, 49 (59.8%) showed decreased percentages of B lymphocytes, and 69 (84.1%) showed decreased percentages of natural killer cells. Of 88 patients tested for serum immunoglobulins, 40 (45.5%) showed decreased IgA levels. Among 20 patients tested for serum cytokines, 15 (75.0%), 15 (75.0%), 13 (65.0%), and 12 (60.0%) showed elevated levels of interleukin (IL) -5, IL-6, IL-10, and interferon-γ, respectively. All patients received systemic glucocorticoid therapy, among whom 86 additionally received intravenous immunoglobulin therapy, 4 received Janus kinase inhibitors, and 3 received dupilumab. Five patients died, 9 developed hemophagocytic lymphohistiocytosis, 6 developed bronchiolitis obliterans, and 5 experienced long-term immune-related sequelae. Conclusions:Among these children with DIHS, antibiotics were the most common causative drugs, and the latency period could be shorter than 2 weeks. In addition to the common involvement of the liver and lungs, gastrointestinal and cardiac impairments were relatively frequent, while renal involvement was rare. Immunological features included decreased percentages of B lymphocytes and natural killer cells, reduced IgA levels, and elevated levels of cytokines such as IL-5, IL-6, IL-10, and interferon-γ.
7.Guideline for Adult Weight Management in China
Weiqing WANG ; Qin WAN ; Jianhua MA ; Guang WANG ; Yufan WANG ; Guixia WANG ; Yongquan SHI ; Tingjun YE ; Xiaoguang SHI ; Jian KUANG ; Bo FENG ; Xiuyan FENG ; Guang NING ; Yiming MU ; Hongyu KUANG ; Xiaoping XING ; Chunli PIAO ; Xingbo CHENG ; Zhifeng CHENG ; Yufang BI ; Yan BI ; Wenshan LYU ; Dalong ZHU ; Cuiyan ZHU ; Wei ZHU ; Fei HUA ; Fei XIANG ; Shuang YAN ; Zilin SUN ; Yadong SUN ; Liqin SUN ; Luying SUN ; Li YAN ; Yanbing LI ; Hong LI ; Shu LI ; Ling LI ; Yiming LI ; Chenzhong LI ; Hua YANG ; Jinkui YANG ; Ling YANG ; Ying YANG ; Tao YANG ; Xiao YANG ; Xinhua XIAO ; Dan WU ; Jinsong KUANG ; Lanjie HE ; Wei GU ; Jie SHEN ; Yongfeng SONG ; Qiao ZHANG ; Hong ZHANG ; Yuwei ZHANG ; Junqing ZHANG ; Xianfeng ZHANG ; Miao ZHANG ; Yifei ZHANG ; Yingli LU ; Hong CHEN ; Li CHEN ; Bing CHEN ; Shihong CHEN ; Guiyan CHEN ; Haibing CHEN ; Lei CHEN ; Yanyan CHEN ; Genben CHEN ; Yikun ZHOU ; Xianghai ZHOU ; Qiang ZHOU ; Jiaqiang ZHOU ; Hongting ZHENG ; Zhongyan SHAN ; Jiajun ZHAO ; Dong ZHAO ; Ji HU ; Jiang HU ; Xinguo HOU ; Bimin SHI ; Tianpei HONG ; Mingxia YUAN ; Weibo XIA ; Xuejiang GU ; Yong XU ; Shuguang PANG ; Tianshu GAO ; Zuhua GAO ; Xiaohui GUO ; Hongyi CAO ; Mingfeng CAO ; Xiaopei CAO ; Jing MA ; Bin LU ; Zhen LIANG ; Jun LIANG ; Min LONG ; Yongde PENG ; Jin LU ; Hongyun LU ; Yan LU ; Chunping ZENG ; Binhong WEN ; Xueyong LOU ; Qingbo GUAN ; Lin LIAO ; Xin LIAO ; Ping XIONG ; Yaoming XUE
Chinese Journal of Endocrinology and Metabolism 2025;41(11):891-907
Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.
8.Expert consensus on visualized tele-round and quality control management based on the improvement of clinical practice ability
Wanhong YIN ; Xiaoting WANG ; Ran ZHOU ; Dawei LIU ; Yan KANG ; Yaoqing TANG ; Xiaochun MA ; Jianguo LI ; Zhenjie HU ; Haitao ZHANG ; Wei HE ; Lixia LIU ; Wenjin CHEN ; Ran ZHU ; Jun WU ; Hongmin ZHANG ; Lina ZHANG ; Wenzhao CHAI ; Shihong ZHU ; Wangbin XU ; Rongqing SUN ; Xiangyou YU ; Tianjiao SONG ; Ying ZHU ; Hong REN ; Ai SHANMU ; Qing ZHANG ; Wei FANG ; Xiuling SHANG ; Liwen LYU ; Shuhan CAI ; Xin DING ; Heng ZHANG ; Guang FENG ; Lipeng ZHANG ; Bo HU ; Dong ZHANG ; Weidong WU ; Feng SHEN ; Xiaojun YANG ; Zhenguo ZENG ; Qibing HUANG ; Xueying ZENG ; Tongjuan ZOU ; Milin PENG ; Yulong YAO ; Mingming CHEN ; Hui LIAN ; Jingmei WANG ; Yong LI ; Feng QU ; Gang YE ; Rongli YANG ; Xiukai CHEN ; Suwei LI ; Juxiang WANG ; Yangong CHAO
Chinese Journal of Internal Medicine 2025;64(2):101-109
Turning to critical illness is a common stage of various diseases and injuries before death. Patients usually have complex health conditions, while the treatment process involves a wide range of content, along with high requirements for doctor′s professionalism and multi-specialty teamwork, as well as a great demand for time-sensitive treatments. However, this is not matched with critical care professionals and the current state of medical care in China. Telemedicine, which shortens the distance of medical professionals and the gap of disease diagnosis and treatments in various regions through electronic information, can effectively solve the current problem. Therefore, there is an urgent need to develop a standardized, high-quality visualization telemedicine round system .Therefore, experts have been organized to search domestic and foreign literature on telemedicine round for critically ill patients and to form this consensus based on clinical experiences so as to further improve the level of critical care treatments in regions.
9.Antiviral mechanism of Euphorbia helioscopia diterpenoids against Zika virus in vitro
Pan-pan PANG ; Xiong QIU ; Ying-jie JIANG ; Xin-yue LIU ; Wei-zhe MA ; Jian-qiu-rong YIN ; Wei-lie XIAO ; Chang-bo ZHENG
Chinese Pharmacological Bulletin 2025;41(8):1436-1444
Aim To investigate the anti-Zika virus(ZIKV)mechanism of diterpenoid compound 9 from Euphorbia helioscopia in vitro.Methods The cytotox-icity of compound 9 was evaluated using the CCK-8 as-say.A ZIKV-infected Vero cell model was established,and the antiviral activity was assessed through RT-qPCR,plaque assay,Western blot,and immunofluores-cence.Furthermore,the mechanism of action was elu-cidated using multi-cell line validation,nanoparticle tracking analysis,cellular thermal shift assay,and mo-lecular docking.Results In Vero cells,compound 9 exhibited an EC50 of(3.95±0.15)μmol·L-1 and a CC50 of(272.12±8.56)μmol·L-1,demonstrating significantly higher antiviral efficacy than the positive control drug ribavirin(RBV).Its virus inactivation effect was time-dependent and could significantly re-duce viral load and plaque formation.Studies revealed that compound 9 altered the physicochemical properties of ZIKV particles,including reducing surface charge and increasing particle size distribution.Additionally,it significantly enhanced the thermal stability of the prM protein.Molecular docking analysis indicated that compound 9 formed a high-affinity interaction with the prM protein(binding energy:-38.52 kJ·mol-1)and stabilized its structure through hydrophobic interac-tions.Conclusion Compound 9 exerts in vitro anti-ZIKV activity by directly inactivating the virus,disrup-ting viral particle integrity,and targeting the prM pro-tein.
10.Effects and mechanisms of high-dose glucocorticoids on senescence, apoptosis, and osteogenic differentiation of bone marrow mesenchymal stem cells
Zhendong YING ; Changjun CHEN ; Dailing CHEN ; Qiuru WANG ; Qibin LIU ; Qingwei MA ; Lei ZHANG ; Pengde KANG ; Xin ZHAO
Chinese Journal of Orthopaedics 2025;45(18):1208-1216
Objective:To elucidate the molecular mechanisms through which high-dose dexamethasone exerts long-term effects on bone marrow mesenchymal stem cells (BMSCs), specifically its role in suppressing osteogenic differentiation, accelerating cellular senescence, triggering the senescence-associated secretory phenotype (SASP), and inducing apoptosis.Methods:Primary rat BMSCs were isolated and treated with high-dose dexamethasone (1×10 -4 mol/L) to establish the experimental group, while untreated cells served as the control. The gene and protein expression levels of osteogenic markers, bone alkaline phosphatase (bALP) and Runt-related transcription factor 2 (Runx2), were analyzed in both groups. Cellular senescence was evaluated using senescence-associated β-galactosidase (SA-β-gal) staining. The expression of senescence-related markers (P16 and P21), components of the senescence-associated secretory phenotype (SASP), including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and interferon (IFN)-γ, as well as apoptosis-related proteins (Bcl-2, Bax, and Cleaved-Caspase-3), and key factors of the Nrf2/HO-1 signaling pathway were assessed at both transcriptional and protein levels using qRT-PCR, immunofluorescence, and Western-blot analyses. These comprehensive evaluations aimed to determine the senescent state, apoptotic features, and alterations in osteogenic differentiation of BMSCs. Results:Following treatment with dexamethasone and subsequent withdrawal, both qRT-PCR and Western blot analyses indicated a significant reduction in the expression of the osteogenic markers bALP and Runx2 at both mRNA and protein levels. The proportion of SA-β-gal positive cells was markedly higher in the dexamethasone group (74.33%±6.89%) than in the control group (20.30%±1.57%, t=17.300, P<0.001). qRT-PCR analysis revealed upregulated mRNA expression of the senescence-related genes P16 and P21 after dexamethasone treatment, which was further supported at the protein level by immunofluorescence showing increased P21 expression. Western-blot results confirmed that protein expression levels of P16 and P21 were significantly elevated in the dexamethasone group (7.025±0.255 and 6.362±0.456, respectively) compared with the control group (1.016±0.115 and 0.816±0.172; both P<0.05). Furthermore, gene expression levels of the senescence-associated secretory phenotype (SASP) factors TNF-α and IL-1β were significantly increased (TNF-α: 3.539±0.599 vs. 0.742±0.095; IL-1β: 4.469±0.331 vs. 0.799±0.175; both P<0.05), and their protein expression was consistently upregulated as validated by Western-blot. Additionally, protein expression levels of TNF-α, IL-1β, and IFN-γ were significantly higher in the dexamethasone-treated group (3.476±0.932 vs. 0.945±0.095; 4.111±0.220 vs. 0.762±0.105; 2.155±0.240 vs. 0.656±0.104; all P<0.05).Western-blot analysis also demonstrated that protein expression of Nrf2 and HO-1 was significantly suppressed in the dexamethasone group (0.21±0.07 and 0.19±0.06, respectively) compared with the control group (1.13±0.15 and 0.92±0.21; P<0.05). Moreover, Western-blot analysis revealed that the expression levels of the pro-apoptotic proteins Bax and Cleaved-Caspase-3 were significantly up, regulated in the dexamethasone, treated BMSCs (Bax: 3.673±0.397 vs. 0.453±0.111; Cleaved-Caspase-3: 3.863±0.399 vs. 0.465±0.057), while the expression of the anti-apoptotic protein Bcl-2 was markedly down, regulated (0.959±0.073 vs. 2.126±0.195), with all differences being statistically significant ( P<0.05). Conclusions:High-dose dexamethasone treatment of BMSCs, followed by withdrawal of dexamethasone, induces cellular senescence and enhances the expression of the senescence-associated secretory phenotype (SASP) through suppression of the Nrf2/HO-1 signaling pathway. Concurrently, it promotes apoptosis by activating the mitochondrial apoptotic pathway, collectively leading to impaired osteogenic differentiation of BMSCs.

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