1.Inverse Association Between Alcohol Consumption and Parkinson’s Disease Risk and Identification of RIT2 as a Linked Biomarker
Wei LU ; Xiu-Li CHENG ; Xiao-Yun PAN ; Dan-Dan YANG ; Hui-Ling ZOU ; Li-Guo DONG ; Yi-Liang WEI ; Gui-Yun CUI
Progress in Biochemistry and Biophysics 2026;53(6):1723-1733
ObjectiveAs a common lifestyle habit, alcohol consumption has a controversial association with the onset of Parkinson’s disease (PD). To demonstrate the correlation between alcohol consumption and PD and to identify associated genes, we integrated findings from clinical surveys, genomics, transcriptomics, and animal experiments. MethodsWe investigated the alcohol consumption rates (including both before and after disease onset) among 244 PD patients in China and 177 PD patients from the U.S. NHANES database. Mendelian randomization (MR) analysis was performed using genome-wide association study (GWAS) data for three alcohol-related traits and seven PD-related datasets from the MRC IEU OpenGWAS database. Transcriptomic data from the substantia nigra of PD patients were obtained from three GEO datasets (GSE7621, GSE20141, and GSE49036) to analyze RIT2 gene transcription. Finally, three groups of animal experiments (water/20% ethanol/20% liquor, with 4 C57BL/6J mice per group) were conducted to examine changes in brain RIT2 gene expression and transcriptomic profiles following alcohol consumption. ResultsThe alcohol consumption rates among PD patients in China and the U.S. (9%-18.87%) were significantly lower than the general population rates of 15%-45% in their respective regions (P<0.001), suggesting a possible negative association between alcohol consumption and PD. Subsequently, in 21 bidirectional MR analyses using 3 alcohol-related GWAS datasets and 7 PD-related GWAS datasets, the forward MR analyses (alcohol intake as exposure, PD as outcome) yielded 12 negative associations (ORIVW<1) and 9 positive associations (ORIVW>1). Among these, only two negative associations reached statistical significance: alcohol intake frequency (ORIVW=0.75, 95% CI: 0.60-0.93, P=0.010) and alcohol consumption (ORIVW=0.20, 95% CI: 0.05-0.83, P=0.026). The forward MR analysis (alcohol intake→PD) identified 235 SNPs, annotated to 316 genes, while the reverse MR analyses (PD→alcohol intake) identified 37 SNPs, annotated to 53 genes. Notably, only the RIT2 gene appeared in both the forward and reverse MR analyses (alcohol intake→PD: rs28597806, rs8083110; PD→alcohol intake: rs4588066). RIT2 is selectively expressed in the human brain (FPKM: 5.259±2.103), with low or no expression in peripheral tissues (FPKM: <1). Analysis of three human substantia nigra transcriptomic datasets revealed a decreasing trend in RIT2 gene expression in PD patients (GSE20141 array signal: 3.49±1.23 vs. 2.33±0.87, P=0.044). Animal experiments demonstrated that administration of 20% ethanol or 20% liquor (approximately 8% ethanol) stimulated a >2-fold upregulation of RIT2 gene expression in the mouse brain. Furthermore, transcriptomic sequencing revealed that the two alcohol-treated groups exhibited 96 (20% ethanol vs. water control) and 4 (20% liquor vs. water control) differentially expressed genes, respectively, indicating that low-dose alcohol consumption can achieve RIT2 upregulation while minimizing impact on other brain genes. In addition to its anti-infective effects, low-dose alcohol consumption primarily influences signaling pathways related to neurodegenerative diseases such as PD and Prion diseases. ConclusionAlcohol consumption is generally considered as a harmful lifestyle habit. However, some studies have also shown a lower risk of mortality among individuals who consume low doses of alcohol (100 g/week of ethanol) or drink occasionally. Currently, one of the research focuses on alcohol consumption is whether the human body can benefit from low-dose alcohol intake. This study provides new evidence supporting a negative association between alcohol consumption and PD, and for the first time, through MR analysis, identifies the RIT2 gene as a potential mediator of the effect of alcohol consumption on PD. RIT2 is selectively expressed in the human brain. Building upon existing evidence indicating downregulated RIT2 gene expression in PD pathogenesis, our experiments confirm that low-dose alcohol consumption can upregulate RIT2 expression in the brain. In brief, alcohol consumption may suppress the pathogenesis of PD by upregulating RIT2 expression in the substantia nigra. China is facing a serious problem of population aging. This study offers important insights for long-term PD prevention and treatment strategies, with the aim of benefiting more potential PD patients through lifestyle modifications, thereby improving the quality of life of the aging population and reducing the economic burden on healthcare.
2.Endoplasmic reticulum membrane remodeling by targeting reticulon-4 induces pyroptosis to facilitate antitumor immune.
Mei-Mei ZHAO ; Ting-Ting REN ; Jing-Kang WANG ; Lu YAO ; Ting-Ting LIU ; Ji-Chao ZHANG ; Yang LIU ; Lan YUAN ; Dan LIU ; Jiu-Hui XU ; Peng-Fei TU ; Xiao-Dong TANG ; Ke-Wu ZENG
Protein & Cell 2025;16(2):121-135
Pyroptosis is an identified programmed cell death that has been highly linked to endoplasmic reticulum (ER) dynamics. However, the crucial proteins for modulating dynamic ER membrane curvature change that trigger pyroptosis are currently not well understood. In this study, a biotin-labeled chemical probe of potent pyroptosis inducer α-mangostin (α-MG) was synthesized. Through protein microarray analysis, reticulon-4 (RTN4/Nogo), a crucial regulator of ER membrane curvature, was identified as a target of α-MG. We observed that chemically induced proteasome degradation of RTN4 by α-MG through recruiting E3 ligase UBR5 significantly enhances the pyroptosis phenotype in cancer cells. Interestingly, the downregulation of RTN4 expression significantly facilitated a dynamic remodeling of ER membrane curvature through a transition from tubules to sheets, consequently leading to rapid fusion of the ER with the cell plasma membrane. In particular, the ER-to-plasma membrane fusion process is supported by the observed translocation of several crucial ER markers to the "bubble" structures of pyroptotic cells. Furthermore, α-MG-induced RTN4 knockdown leads to pyruvate kinase M2 (PKM2)-dependent conventional caspase-3/gasdermin E (GSDME) cleavages for pyroptosis progression. In vivo, we observed that chemical or genetic RTN4 knockdown significantly inhibited cancer cells growth, which further exhibited an antitumor immune response with anti-programmed death-1 (anti-PD-1). In translational research, RTN4 high expression was closely correlated with the tumor metastasis and death of patients. Taken together, RTN4 plays a fundamental role in inducing pyroptosis through the modulation of ER membrane curvature remodeling, thus representing a prospective druggable target for anticancer immunotherapy.
Pyroptosis/immunology*
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Humans
;
Endoplasmic Reticulum/immunology*
;
Animals
;
Nogo Proteins/antagonists & inhibitors*
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Mice
;
Cell Line, Tumor
;
Xanthones/pharmacology*
;
Neoplasms/pathology*
;
Mice, Nude
3.Exploration and Practice of Artificial Intelligence Empowering Case-based Teaching in Biochemistry and Molecular Biology
Ying-Lu HU ; Yi-Chen LIN ; Jun-Ming GUO ; Xiao-Dan MENG
Progress in Biochemistry and Biophysics 2025;52(8):2173-2184
In recent years, the deep integration of artificial intelligence (AI) into medical education has created new opportunities for teaching Biochemistry and Molecular Biology, while also offering innovative solutions to the pedagogical challenges associated with protein structure and function. Focusing on the case of anaplastic lymphoma kinase (ALK) gene mutations in non-small-cell lung cancer (NSCLC), this study integrates AI into case-based learning (CBL) to develop an AI-CBL hybrid teaching model. This model features an intelligent case-generation system that dynamically constructs ALK mutation scenarios using real-world clinical data, closely linking molecular biology concepts with clinical applications. It incorporates AI-powered protein structure prediction tools to accurately visualize the three-dimensional structures of both wild-type and mutant ALK proteins, dynamically simulating functional abnormalities resulting from conformational changes. Additionally, a virtual simulation platform replicates the ALK gene detection workflow, bridging theoretical knowledge with practical skills. As a result, a multidimensional teaching system is established—driven by clinical cases and integrating molecular structural analysis with experimental validation. Teaching outcomes indicate that the three-dimensional visualization, dynamic interactivity, and intelligent analytical capabilities provided by AI significantly enhance students’ understanding of molecular mechanisms, classroom engagement, and capacity for innovative research. This model establishes a coherent training pathway linking “fundamental theory-scientific research thinking-clinical practice”, offering an effective approach to addressing teaching challenges and advancing the intelligent transformation of medical education.
4.Exercise preconditioning alleviates motor deficits in MPTP-induced Parkinsonian mice by improving mitochondrial function.
Miao-Miao XU ; Dan-Ting HU ; Qiao ZHANG ; Xiao-Guang LIU ; Zhao-Wei LI ; Li-Ming LU
Acta Physiologica Sinica 2025;77(3):419-431
Parkinson's disease (PD) is a common neurodegenerative disorder mainly related to mitochondrial dysfunction of dopaminergic neurons in the midbrain substantia nigra. This study aimed to investigate the effects of exercise preconditioning on motor deficits and mitochondrial function in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model. Eight-week-old male C57BL/6J mice were randomly divided into four groups: sedentary + saline (SS), sedentary + MPTP (SM), exercise + saline (ES), and exercise + MPTP (EM) groups. Mice in the ES and EM groups received 4 weeks of treadmill training, and then SM and EM groups were treated with MPTP for 5 days. Motor function was assessed by behavioral tests, and morphological and functional changes in dopaminergic neurons and mitochondria in the substantia nigra of the midbrain were evaluated using immunohistochemistry, Western blot, and transmission electron microscopy technology. The results showed that, compared with the SM group, the EM group exhibited significantly improved motor ability, up-regulated protein expression levels of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the midbrain, and down-regulated protein expression of α-synuclein (α-Syn) in the mitochondria of substantia nigra. Compared with the SM group, the EM group showed up-regulated protein expression levels of mitochondrial fusion proteins, including optical atrophy protein 1 (OPA1) and mitofusin 2 (MFN2), and biogenesis-related proteins, including peroxisome proliferator activated receptor gamma coactivator 1α (PGC-1α) and mitochondrial transcription factor A (TFAM), while the protein expression levels of dynamin-related protein 1 (DRP1) and mitochondrial fission protein 1 (FIS1) were significantly down-regulated. Compared with the SM group, the EM group showed significantly reduced damage to substantia nigra mitochondria, restored mitochondrial membrane potential and ATP production, and decreased levels of reactive oxygen species (ROS). These results suggest that 4-week treadmill pre-training can alleviate MPTP-induced motor impairments in PD mice by improving mitochondrial function, providing a theoretical basis for early exercise-based prevention of PD.
Animals
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Male
;
Physical Conditioning, Animal/physiology*
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Mice
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Mice, Inbred C57BL
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Mitochondria/physiology*
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Dopaminergic Neurons
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MPTP Poisoning/physiopathology*
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Substantia Nigra
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Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
;
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine
5.A convenient research strategy for functional verification of epigenetic regulators during spermatogenesis.
Shan LI ; Ying YUAN ; Ke-Yu ZHANG ; Yi-Dan GUO ; Lu-Tong WANG ; Xiao-Yuan ZHANG ; Shu ZHANG ; Qi YAN ; Rong ZHANG ; Jie CHEN ; Feng-Tang YANG ; Jing-Rui LI
Asian Journal of Andrology 2025;27(2):261-267
Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells (SSCs). The mechanisms underlying the transition from SSCs to sperm are largely unknown. Most studies utilize gene knockout mice to explain the mechanisms. However, the production of genetically engineered mice is costly and time-consuming. In this study, we presented a convenient research strategy using an RNA interference (RNAi) and testicular transplantation approach. Histone H3 lysine 9 (H3K9) methylation was dynamically regulated during spermatogenesis. As Jumonji domain-containing protein 1A (JMJD1A) and Jumonji domain-containing protein 2C (JMJD2C) demethylases catalyze histone H3 lysine 9 dimethylation (H3K9me2), we firstly analyzed the expression profile of the two demethylases and then investigated their function. Using the convenient research strategy, we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases. These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.
Spermatogenesis/physiology*
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Animals
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Male
;
Mice
;
Epigenesis, Genetic
;
Jumonji Domain-Containing Histone Demethylases/metabolism*
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Histones/metabolism*
;
RNA Interference
;
Testis/metabolism*
;
Methylation
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Mice, Knockout
;
Histone Demethylases
6.Ultra-early administration of eculizumab in a child with atypical hemolytic uremic syndrome: a case report.
Dan-Dan GUO ; Yi-Xin XIAO ; Wei-Rui WANG ; Xiao-Lu DENG ; Ye-Hong HUANG
Chinese Journal of Contemporary Pediatrics 2025;27(11):1408-1413
A 10-year-old girl was admitted with a 38-hour history of widespread subcutaneous petechiae and hematuria and a 6-hour history of jaundice and oliguria. Physical examination revealed widespread subcutaneous petechiae and jaundice of the skin and sclera. Laboratory tests showed anemia, thrombocytopenia, acute kidney injury, and markedly elevated lactate dehydrogenase. Thrombotic microangiopathy was initially diagnosed, with a high suspicion of atypical hemolytic uremic syndrome (aHUS). Eculizumab was initiated within 9 hours of admission (within 48 hours of onset). After the first infusion, hemolysis rapidly ceased, and the platelet count and renal function gradually returned to normal. Whole-exome sequencing identified homozygous deletions of CFHR1 exon 2 and CFHR4 exon 1. aHUS typically has abrupt onset and rapid progression. Clinicians should maintain high suspicion for aHUS when the triad of thrombocytopenia, microangiopathic hemolytic anemia, and acute kidney injury is present. Ultra-early eculizumab (within 48 hours of onset) rapidly blocks complement-mediated thrombotic microangiopathy, reverses organ injury, and improves long-term prognosis. Additionally, complement-related genetic testing is important for etiological clarification and individualized determination of eculizumab treatment duration.
Humans
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Antibodies, Monoclonal, Humanized/administration & dosage*
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Female
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Atypical Hemolytic Uremic Syndrome/drug therapy*
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Child
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Complement C3b Inactivator Proteins
7.Retrospective Analysis of Venetoclax Combined with Azacitidine Compared with "3+7" or Similar Regimens for Newly Diagnosed Patients with Acute Myeloid Leukemia.
Lu-Lu WANG ; Juan ZHANG ; Yue ZHANG ; Yong ZHANG ; Xiao-Min DONG ; Dan-Yang ZHANG ; Ting-Ting CHEN ; Yun-Hui ZHOU ; Teng WANG ; Hui-Ling LAN ; He-Bing ZHOU
Journal of Experimental Hematology 2025;33(3):672-681
OBJECTIVE:
To retrospectively analyze the clinical data of newly diagnosed acute myeloid leukemia (AML) patients treated with venetoclax combined with azacitidine (Ven/Aza) or standard "3+7" regimen and similar regimens, collect real-world study data, compare the treatment response and adverse events between the two regimens, as well as perform survival analysis.
METHODS:
To retrospectively analyze the efficacy, survival, and adverse reactions of newly diagnosed AML patients treated with Ven/Aza (24 cases) and "3+7" regimens (117 cases ) in our hospital from September 2009 to March 2023, as well as factors influencing outcomes. A propensity score matching (PSM) was performed on age and Eastern Cooperative Oncology Group performance status (ECOG PS) to obtain a 1:1 matched cohort of 20 pairs, and the efficacy and survival before and after the matching were compared.
RESULTS:
The median age of patients in the Ven/Aza group was 69 years, while that in the "3+7" group was 56 years (P <0.001). Objective remission rate (ORR) was 62.5% in Ven/Aza group and 74.8% in "3+7" group (P >0.05). The median overall survival (OS) in the Ven/Aza group was 522 days, while that in the "3+7" group was 1 002 days (P >0.05). After controlling the two variables of age and ECOG PS, a PSM cohort of 20 pairs was obtained, in which the ORR was 65% in Ven/Aza group and 60% in "3+7" group (P >0.05). The median OS was 522 days and 629 days, and median progression-free survival (PFS) was 531 days and 198 days between the two groups, respectively. There were no statistically significant differences in OS and PFS between the two groups (both P >0.05). Additionally, the incidence of adverse events in the Ven/Aza group was significantly reduced.
CONCLUSION
The overall cohort shows that the "3+7" regimen has advantages in efficacy and survival, but Ven/Aza regimen is relatively safer. After performing PSM on age and ECOG PS, the Ven/Aza group showed improved efficacy, and a longer median PFS compared to "3+7" group.
Humans
;
Leukemia, Myeloid, Acute/drug therapy*
;
Retrospective Studies
;
Sulfonamides/administration & dosage*
;
Azacitidine/administration & dosage*
;
Bridged Bicyclo Compounds, Heterocyclic/administration & dosage*
;
Aged
;
Middle Aged
;
Male
;
Female
;
Antineoplastic Combined Chemotherapy Protocols/therapeutic use*
;
Treatment Outcome
8.Optimization of cellulase-assisted ultrasound extraction process for total flavonoids from Plumbago zeylanica and evaluation of their anti-oxidant activity
Xiao-lu GAO ; Wen-de CHENG ; Yue-yuan WEN ; Shang-ping XING ; Cheng SHI ; Dan ZHU ; Ya-nan XU
Chinese Traditional Patent Medicine 2025;47(11):3580-3585
AIM To optimize the cellulase-assisted ultrasound extraction process for total flavonoids from Plumbago zeylanica L.,and to evaluate their anti-oxidant activity.METHODS With extraction time,liquid-solid ratio,cellulase addition amount,extraction temperature and ultrasonic power as influencing factors,extraction rate of total flavonoids as an evaluation index,the extraction process was optimized by response surface method on the basis of single factor test.Subsequently,The scavenging rates of extract on DPPH,ABTS and OH free radicals were determined.RESULTS The optimal conditions were determined to be 34∶1 for liquid-solid ratio,3%for cellulase addition amount,51 ℃ for extraction temperature,38 min for extraction time,and 400 W for ultrasonic power,the extraction rate of total flavonoids was(33.411±0.97)%.The IC50 values of three free radicals were 0.13,0.042,3.29 mg/mL,respectively.CONCLUSION This reasonable and reliable method can be used for the cellulase-assisted ultrasound extraction of total flavonoids from P.zeylanica with strong anti-oxidant activity.
9.An Electronic Microbial Growth Analyzer-based Method for Rapidly Screening Viable Salmonella in Food
Ruo-Han LIANG ; Xiao-Dan PU ; Feng LU ; Xue-Ting ZHU ; Yuan-Yuan ZHANG ; Xiao-Yang WANG ; Qian-Qian YANG ; Hao LI ; Xu-Zhi ZHANG ; Chen-Zhong LI ; Shan LIU
Chinese Journal of Analytical Chemistry 2025;53(10):1694-1704
Foodborne illnesses caused by Salmonella pose significant threats to worldwide public health safety.In this study,a rapid method for screening viable Salmonella in oyster sauce and milk was developed by utilizing an electronic microbial growth analyzer(EMGA).Target food samples were diluted 10-fold with RVS broth and loaded into test tubes.Test tubes were positioned in the EMGA to determine the bacterial growth curves and the time required to reach the maximum growth rate(Tmgr).Using Salmonella typhimurium(S.typhimurium)asan model species,there was linear relationship between the logarithmic value of viable bacterial concentration(lgC)and Tmgr over the range of 5×101-5×106 CFU/mL,with a detection limit of 10 CFU/mL.For oyster sauce,the regression equation was Tmgr(min)=-80.775lg[C/(CFU/mL)]+754.96(R2=0.9907),and the recovery rates of S.typhimurium ranged from 95.2%to 119.8%,with relative standard deviations(RSD)ranging from 3.5%to 16.3%.For milk,the regression equation was Tmgr(min)=-71.922 lg[C/(CFU/mL)]+618.65(R2=0.9985),with recovery rates ranging from 98.4%to 110.6%and RSD ranging from 6.4%to 12.8%.The EMGA method required only one portable instrument,and involving only three manual steps,i.e.,dilution,transfer,and insertion.When S.typhimurium contamination reached 106 CFU/mL,the total time consumption,from the unwrapping of samples to the readout of bacterial concentration,was no more than 7 h.When applied to detection of actual oyster sauce and milk samples,the new method demonstrated strong consistency with plate counting results in positive detection rates.This method was superior to the plate counting method,which was generally considered as a gold standard,in terms of accuracy,precision,simplicity and efficiency,representing a promising alternative for the on-site screening and quantification of viable Salmonella in oyster sauce and milk products.
10.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.

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