1.The Role and Molecular Mechanism of N⁶-methyladenosine Modification in Spermatogenesis
Shi-Qi MENG ; Wen-Ting LU ; Xu CHENG ; Fan YANG ; Chang-Min NIU ; Ying ZHEGN
Progress in Biochemistry and Biophysics 2026;53(5):1297-1312
Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N6-methyladenosine (m6A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m6A methyltransferases (“writers”) catalyze the addition of a methyl group to the N6 position of adenosine, m6A demethylases (“erasers”) remove the modification, and m6A-binding proteins (“readers”) recognize m6A-modified transcripts. Through the coordinated actions of these factors, m6A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m6A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m6A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m6A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m6A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m6A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m6A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m6A-related proteins can function through noncanonical mechanisms independent of m6A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m6A regulatory system. Dysregulation of m6A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m6A-dependent and -independent mechanisms, the spatiotemporal dynamics of m6A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m6A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.
2.The Role and Molecular Mechanism of N⁶-methyladenosine Modification in Spermatogenesis
Shi-Qi MENG ; Wen-Ting LU ; Xu CHENG ; Fan YANG ; Chang-Min NIU ; Ying ZHEGN
Progress in Biochemistry and Biophysics 2026;53(5):1297-1312
Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N6-methyladenosine (m6A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m6A methyltransferases (“writers”) catalyze the addition of a methyl group to the N6 position of adenosine, m6A demethylases (“erasers”) remove the modification, and m6A-binding proteins (“readers”) recognize m6A-modified transcripts. Through the coordinated actions of these factors, m6A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m6A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m6A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m6A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m6A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m6A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m6A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m6A-related proteins can function through noncanonical mechanisms independent of m6A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m6A regulatory system. Dysregulation of m6A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m6A-dependent and -independent mechanisms, the spatiotemporal dynamics of m6A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m6A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.
3.Molecular Mechanisms of Intraflagellar Transport in Regulating ciliogenesis and Ciliopathies
Ting-Ting GE ; Fan YANG ; Chang-Min NIU ; Ying ZHENG
Progress in Biochemistry and Biophysics 2026;53(8):2179-2193
Intraflagellar transport (IFT) is a core mechanism for ciliary assembly, length maintenance, ciliary proteome homeostasis and signal transduction. Most proteins required for ciliary structure and function are synthesized in the cytoplasm. Because the ciliary compartment is separated from the cell body by the selective barrier of the transition zone, these proteins cannot freely equilibrate between the cytoplasm and the cilium. Consequently, axonemal components, membrane proteins and signaling molecules must be actively imported into cilia, retrieved from the ciliary compartment, and recycled or degraded through highly ordered transport and sorting pathways. The IFT system is mainly composed of the IFT-A complex, IFT-B complex, kinesin-2, dynein-2 and the Bardet-Biedl syndrome protein complex (BBSome). Through coordinated anterograde and retrograde transport, these modules mediate the dynamic trafficking of different classes of ciliary cargoes. Anterograde transport delivers structural and membrane-associated components from the ciliary base toward the ciliary tip, whereas retrograde transport retrieves IFT components and selected cargoes back toward the ciliary base and cytoplasm. In this way, IFT not only supports the construction of the axoneme but also contributes to the maintenance of ciliary composition and the regulation of ciliary signaling activity. In recent years, advances in cryo-electron microscopy, in situ cryo-electron tomography and single-molecule imaging have greatly improved our understanding of the molecular mechanisms underlying IFT. These approaches have revealed how IFT trains are assembled at the ciliary base, how they move along axonemal microtubule tracks, how they undergo directional switching at the ciliary tip, and how cargoes are retrieved and recycled. Among the IFT modules, IFT-B acts as the major scaffold of IFT trains. It participates in cargo loading, motor coupling and initiation of anterograde transport. IFT-A is involved in retrograde transport, membrane protein adaptor function and train remodeling. The BBSome, through reversible association with the IFT system, regulates ciliary membrane protein sorting, signaling receptor clearance and renewal of the ciliary proteome. These functions indicate that the IFT machinery is not a simple linear transport pathway, but rather a dynamic and reconfigurable transport system. The conversion of transport direction is a key step in the IFT cycle. This process is closely associated with disassembly of anterograde trains, dissociation of kinesin-2, activation of dynein-2 at the ciliary tip and reassembly of retrograde trains. In terms of pathogenic mechanisms, IFT abnormalities may cause ciliopathies through four major pathways: defects in ciliary assembly and structure, abnormal localization of ciliary cargoes, dysregulation of signaling pathways, and impaired cargo unloading and retrieval. These defects can affect multiple organ systems, including the retina, kidney, skeleton, respiratory tract, reproductive system, and neuro-metabolic system. Current therapeutic strategies are still mainly based on symptomatic support and maintenance of organ function. Overall, IFT is a dynamic transport system jointly regulated by axonemal structure, motor activity, cargo selection and cellular signaling. It links ciliary architecture with protein turnover and signaling regulation, thereby playing a fundamental role in both ciliary homeostasis and ciliopathy pathogenesis. Further elucidation of IFT regulatory mechanisms and their relationships with disease phenotypes will help promote mechanism-based classification, genetic diagnosis and precision intervention for ciliopathies.
4.Visualization analysis of macrophage polarization in tissue repair process
Jinxia CHANG ; Yufei LIU ; Shaohui NIU ; Chang WANG ; Jianchun CAO
Chinese Journal of Tissue Engineering Research 2025;29(7):1486-1496
BACKGROUND:During tissue repair and regeneration,macrophages exhibit multiple activities such as promoting inflammation,anti-inflammation,fibrosis,and wound healing at various stages of tissue damage.The heterogeneity and balanced polarization of macrophages are decisive in organ repair. OBJECTIVE:To explore the research hotspots and development trends in the field of macrophage polarization in tissue repair through visualization analysis methods,as well as the research level of global scientific and clinical workers in this field. METHODS:Using bibliometric analysis methods,this study employed Citespace literature visualization analysis software and VOSviewer tools,retrieving related literature from 2013 to 2023 in the Web of Science Core Collection's Science Citation Index Expanded(SCI-Expanded)and Social Sciences Citation Index Expanded(SSCI-Expanded)databases.The analysis results were presented in a dynamic map format,revealing the main trends and focuses of the research. RESULTS AND CONCLUSION:The number of publications in this field had dramatically increased from 2013 to 2023,with a significant rise starting in 2017.Chinese researchers had the highest number of publications,with 642 papers,while American researchers began focusing on this field early on.Professor Elisseeff Hennifer H had made a substantial contribution to the research in this area.Shanghai Jiao Tong University had produced the most publications.In recent years,keywords such as"hyaluronic acid"and"regulation"had been prevalent.Macrophage polarization research in tissue repair primarily concentrates on its multifunctional regulatory mechanisms,interactions with other cell types,and its behavior under specific pathological conditions.The main research areas include the role of macrophages in wound healing,cardiovascular diseases,chronic inflammation,tumor microenvironments,and regenerative medicine.A deeper understanding of the multifunctionality and polarization mechanisms of macrophages can lead to the development of new therapeutic strategies to enhance tissue repair and regeneration,thereby improving patient treatment outcomes.
5.Risk analysis for coil adverse events based on FDA MAUDE database
Jian-wei YANG ; Lin HUANG ; Yu-juan ZHAO ; Yi XUAN ; Jian-jun CAO ; Chang-qing LIU ; Hui-fang NIU ; Xia LI
Chinese Medical Equipment Journal 2025;46(6):83-87
The coil adverse events in the U.S.Food and Drug Administration Manufacturer and User Facility Device Experience(MAUDE)database from January 2021 to June 2024 were analyzed retrospectively.The risks of coils during the clinical application and their causes were explored with hospital survey and expert demonstration in Shandong Province.Some improving measures were put forward for the safe use of coils,including implementing the main responsibility of the registrant,enhancing the professional skills of the using institutions and strengthening the supervision of the supervisory authorities.[Chinese Medical Equipment Journal,2025,46(6):83-87]
6.Brucea javanica Seed Oil Emulsion and Shengmai Injections Improve Peripheral Microcirculation in Treatment of Gastric Cancer.
Li QUAN ; Wen-Hao NIU ; Fu-Peng YANG ; Yan-da ZHANG ; Ru DING ; Zhi-Qing HE ; Zhan-Hui WANG ; Chang-Zhen REN ; Chun LIANG
Chinese journal of integrative medicine 2025;31(4):299-310
OBJECTIVE:
To explore and verify the effect and potential mechanism of Brucea javanica Seed Oil Emulsion Injection (YDZI) and Shengmai Injection (SMI) on peripheral microcirculation dysfunction in treatment of gastric cancer (GC).
METHODS:
The potential mechanisms of YDZI and SMI were explored through network pharmacology and verified by cellular and clinical experiments. Human microvascular endothelial cells (HMECs) were cultured for quantitative real-time polymerase chain reaction, Western blot analysis, and human umbilical vein endothelial cells (HUVECs) were cultured for tube formation assay. Twenty healthy volunteers and 97 patients with GC were enrolled. Patients were divided into surgical resection, surgical resection with chemotherapy, and surgical resection with chemotherapy combining YDZI and SMI groups. Forearm skin blood perfusion was measured and recorded by laser speckle contrast imaging coupled with post-occlusive reactive hyperemia. Cutaneous vascular conductance and microvascular reactivity parameters were calculated and compared across the groups.
RESULTS:
After network pharmacology analysis, 4 ingredients, 82 active compounds, and 92 related genes in YDZI and SMI were screened out. β-Sitosterol, an active ingredient and intersection compound of YDZI and SMI, upregulated the expression of vascular endothelial growth factor A (VEGFA) and prostaglandin-endoperoxide synthase 2 (PTGS2, P<0.01), downregulated the expression of caspase 9 (CASP9) and estrogen receptor 1 (ESR1, P<0.01) in HMECs under oxaliplatin stimulation, and promoted tube formation through VEGFA. Chemotherapy significantly impaired the microvascular reactivity in GC patients, whereas YDZI and SMI ameliorated this injury (P<0.05 or P<0.01).
CONCLUSIONS
YDZI and SMI ameliorated peripheral microvascular reactivity in GC patients. β-Sitosterol may improve peripheral microcirculation by regulating VEGFA, PTGS2, ESR1, and CASP9.
Humans
;
Microcirculation/drug effects*
;
Drugs, Chinese Herbal/administration & dosage*
;
Stomach Neoplasms/physiopathology*
;
Emulsions
;
Male
;
Plant Oils/administration & dosage*
;
Brucea/chemistry*
;
Middle Aged
;
Female
;
Drug Combinations
;
Human Umbilical Vein Endothelial Cells/metabolism*
;
Seeds/chemistry*
;
Injections
;
Vascular Endothelial Growth Factor A/metabolism*
;
Aged
;
Network Pharmacology
7.Effects of methyl oxofulnonone A ameliorates hyperglucose-induced H9c2 cardiomyocyte injury
Ming-hui OUYANG ; Xiao-tong GUO ; Ting LIU ; Li-ying CHENG ; Zi-chang NIU ; Hao-ping MAO
The Chinese Journal of Clinical Pharmacology 2025;41(1):45-49
Objective To investigate the effect and mechanism of methyl oxofulnonone A(META)on high glucose(HG)-induced H9c2 cell injury.Methods H9c2 cells were divided into control group(normal culture),model group(55 mmol·L-1 glucose)and experimental-L,-M,-H groups(55 mmol·L-1 glucose+12.5,25.0,50.0 μmol·L-1 META).Cell viability was detected by cell counting kit-8;intracellular reactive oxygen species(ROS)level was detected by DCFH-DA fluorescent probe;intracellular adenosine triphosphate(ATP)content was detected by luciferase;and autophagy-related protein expression was detected by Western blotting.Results The optical density values of 72-hour cells in the control group,model group and experimental-M,-H groups were 0.91±0.03,0.61±0.01,0.69±0.02 and 0.72±0.03;the ROS levels were(40.75±1.53)%,(43.73±1.30)%,(30.87±1.27)%and(28.28±1.43)%;the ATP contents were(8.16±0.71),(4.03±0.29),(5.29±0.31)and(5.83±0.31)nmol·mg-1;the relative expression levels of autophagy-related gene 5 protein were 1.05±0.06,1.46±0.09,0.98±0.11 and 0.89±0.09;the relative expression levels of ubiquitin-binding protein were 1.05±0.10,0.55±0.13,0.89±0.04 and 0.98±0.04;the ratios of microtubule-associated protein 1 light chain 3 11/Ⅰ protein were 1.09±0.09,1.82±0.05,1.67±0.29 and 1.09±0.15,respectively.Among the above indicators,there were statistically significant differences between the model group and the control and experimental-M,-H groups(P<0.05,P<0.01).Conclusion META significantly ameliorates H9c2 cardiomyocyte damage caused by high glucose,ameliorates oxidative stress,protects mitochondrial respiration and inhibits autophagy.
8.Investigation of the reprocessing of multiplexing disinfectant items in central sterile supply departments of 1 603 hospitals in China
Xiaoli LI ; Baohua LI ; Jie KANG ; Wenjun FU ; Chang NIU ; Shan OU ; Xue LI
Chinese Journal of Nursing 2025;60(13):1631-1638
Objective To understand the current situation of reprocessing reusable sterilized items in the central sterile supply departments(CSSD)of hospitals and provide a scientific basis for further standardized management.Methods Using the convenience sampling method,a self-designed questionnaire on the current situation of reprocessing of reusable disinfection items in CSSDs was used to conduct a survey in 31 provinces(autonomous regions and municipalities)from June 11th to 23rd,2024.The questionnaire covered 2 aspects,including the basic situation of the hospital and the reprocessing of disinfection items.Results A total of 1 835 questionnaires were distributed,and 1 603 valid questionnaires were retrieved.Regarding the use of reusable disinfection items,with the most frequently used items being humidification bottles,tourniquets,breathing bags and their accessories,and ventilator tubing systems etc.Among them,1 558 hospitals(97.19%)established standardized disposal procedures,and 996 hospitals(62.13%)assigned dedica-ted personnel to be responsible.In terms of the reprocessing procedures of reusable disinfection items,all 1 603 hospitals carried out drying process for the items;the main packaging method was plastic self-sealing bags(59.95%),and 541 hospitals(33.75%)sterilized the packaging materials.Additionally,935 hospitals(58.33%)used oil-free air compressors;among them,51 hospitals(58.62%)installed activated carbon filters at the end of the compressors.Conclusion The current situation of reprocessing reusable sterilized items in CSSDs of nationwide hospitals needs improvement.It is recommended to strengthen the training of professional disinfection knowledge,unify the sterilization standards for plastic self-sealing bags,develop a storage management system,and adopt a medical air compressor system without oil and water to reduce the risk of hospital infections.
9.T1WI deep learning models for evaluating brain injury of neonatal hyperbilirubinemia
Jingwei CUI ; Yongchao NIU ; Beichen XIE ; Chang LIU ; Jinhui DUAN ; Qin XUE ; Ruifang YAN
Chinese Journal of Medical Imaging Technology 2025;41(3):394-398
Objective To observe the value of T1WI deep learning models for evaluating brain injury of neonatal hyperbilirubinemia(NHB).Methods Totally 106 NHB(defined as newborns with neonatal behavioral neurological assessment≤37,NHB group)and 119 non-NHB newborns(control group)in center A,as well as 34 NHB and 18 non-NHB newborns in center B were collected.ROI was delineated based on bilateral globus pallidus on T1WI.A total of 690 slices were obtained by preprocessing data of center A and then were divided into training set(n=552)and test set(n=138)at a ratio of 8∶2.ResNet18,DenseNet121 and EfficientNetB0 models was established,respectively.External validation was performed based on data of center B.Receiver operating characteristic curves were drawn,area under the curves(AUC)were calculated to evaluate the performance of models for assessing NHB brain injuries compared with traditional visual analysis.Results The AUC of ResNet18 model for evaluating NHB brain injury was 0.910-0.990,significantly higher than that of DenseNet121 model(0.710-0.820)and EfficientNetB0 model(0.640-0.740)(all P<0.001).The accuracy,sensitivity and precision of ResNet18 model for evaluating NHB brain injury were all higher than those of visual analysis(all P<0.05),while no significant difference of specificity was found between the above two(P>0.05).Conclusion T1WI ResNet18 model showed excellent performance and generalization ability for evaluating NHB brain injury.
10.Research progress in selection principles and treatment methods for mid-to-late stage ankle arthritis
Hengyu LIU ; Yaokuan RUAN ; Zhende JIANG ; Hanyang ZHANG ; Yuxuan NIU ; Pu LI ; Nan MEI ; Fei CHANG
Journal of Jilin University(Medicine Edition) 2025;51(1):266-274
Mid-to-late stage ankle arthritis is a chronic degenerative disease that is extremely common in clinical practice.It is characterized by significant cartilage degeneration and subchondral bone sclerosis,accompanied by the formation of osteophytes around the joint,often leading to joint deformity.This condition causes severe pain in the patients during walking,severely restricts their activities,and affects their qualities of life.In recent years,with the continuous improvement of medical standards,the treatment methods for mid-to-late stage ankle arthritis have shown a diversified development trend.Non-surgical treatments primarily include activity restriction,orthotic devices,oral non-steroidal anti-inflammatory drugs(NSAIDs),and intra-articular injections of the talocrural joint.The surgical treatments primarily include joint distraction arthroplasty,periacetabular osteotomy,total ankle arthroplasty,and ankle arthrodesis.Tissue engineering therapy,as an emerging method,has also received considerable attention.This article systematically reviewed the selection principles and research progress of various treatment options for mid-to-late stage ankle arthritis,including traditional treatments,non-surgical treatments,surgical treatments,and tissue engineering treatments.By deeply analyzing the basic principles and advantages and disadvantages of each treatment method,and combining the latest research findings on clinical outcomes,a scientific and comprehensive clinical decision-making reference system was constructed to provide clearer and more comprehensive treatment choices for both doctors and patients,thereby effectively improving treatment outcomes and enhancing the quality of life for the patients.

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