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.

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.

ObjectiveTo investigate the effects of metformin on the immune functions of immature dendritic cells （imDCs） and the underlying mechanisms. MethodsMouse bone marrow-derived imDCs were treated with different concentrations of metformin. The working concentration and treatment time of metformin in this study were determined based on the results of cell apoptosis and cell viability assays. The effects of metformin on the phagocytic capacity of imDCs was evaluated using an antigen endocytosis assay. The expression of cluster of differentiation 205 （CD205）， the polymerization of filamentous actin （F-actin）， and the underlying regulatory mechanisms were investigated through flow cytometry， laser confocal fluorescence microscopy， and Western blot. ResultsThe working concentrations of metformin were 1， 2， 4 mmol/L for 24 h determined by the apoptosis and cell viability assays.Metformin significantly suppressed the phagocytic capacity of imDCs， down-regulated the expression of the mannose receptor CD205 on the cell surface， which was closely associated with phagocytic function； metformin inhibited the RhoA-ROCK1-LIMK1-Cofilin signaling pathway， which inhibited the polymerization of F-actin and disturbed its dynamic remodeling of imDCs. ConclusionMetformin can inhibit the expression of CD205 and disrupt the remodeling of F-actin， thereby suppressing the antigen-capturing capacity of imDCs.

Objectives: . This study aimed to investigate the regulatory functions of gamma-aminobutyric acid (GABA)ergic neural circuits from the inferior colliculus (IC) to the medial geniculate body (MGB) in salicylate-induced tinnitus. Methods: . Mice were treated with salicylate to induce tinnitus, and tinnitus-like behaviors were evaluated via gap prepulse inhibition of acoustic startle. Using combined viral tracing methodologies, we identified and mapped the pathways and connections from the IC to the MGB. Furthermore, we employed Gq-coupled human M3 designer receptors exclusively activated by designer drugs (DREADDs) and Gi-coupled human M4 DREADDs to achieve targeted excitation or suppression of GABAergic neurons in the IC and MGB. Following the administration of clozapine N-oxide, which binds to these receptors, we modulated these neural circuits to assess their impact on tinnitus severity in a mouse model. Results: . Our findings demonstrated that mice exposed to salicylate exhibited tinnitus-like behaviors. GABAergic neurons projecting retrogradely from the MGB to the IC were primarily concentrated in the external nucleus of the IC. After clozapine N-oxide administration, chemogenetic activation of IC-MGB GABAergic neurons aggravated salicylate-induced tinnitus. Additionally, activation of GABAergic neurons between the IC and MGB induced the perception of tinnitus even without salicylate. However, chemogenetic inhibition of the IC-MGB GABAergic circuit did not reverse salicylate-induced tinnitus. Conclusion . These findings suggest that activation of the IC-MGB GABAergic neural circuit may contribute to tinnitus generation through a mechanism distinct from that of salicylate-induced tinnitus. This study provides novel insights into the mechanisms underlying tinnitus.

This study was aimed at investigating the immunoregulatory function of Mycobacterium tuberculosis Rv3641c gene in modulating host type Ⅰ interferon responses.The shuttle plasmid pMV261 was used to construct Rv3641c overexpression recombinant Mycobacterium smegmatis,and the biological characteristics of the recombinant bacteria were analyzed to explore the effect of Rv3641c on the growth curve,colony morphology and stress resistance of Mycobacterium.Subsequently,RAW264.7 cells were infected with Rv3641c overexpressing Mycobacterium smegmatis,and the transcriptional expression of genes related to the inhibition of type I inter-feron pathway was determined by RT-PCR.The expression level of IFN-βprotein was determined by ELISA,and the intracellular sur-vival level was determined.As a result,the recombinant rMS::pMV261-Rv3641c was successfully constructed.The results of biologi-cal characteristics analysis showed that Rv3641c did not affect the growth of mycobacteria,but significantly changed the colony mor-phology of mycobacteria and improved its resistance to H2O2.The results of recombinant bacteria infection experiments showed that Rv3641c significantly down-regulated the transcription levels of IFN-α,IFN-βand downstream ISGs genes CXCL10,IFIT2 and IL-1β in host cells,and Rv3641c significantly down-regulated the transcription levels of IFN-α,IFN-βand downstream ISGs genes CXCL10,IFIT2 and IL-1βin host cells.The results of intracellular colonization experiments showed that the intracellular mycobacte-ria in the overexpression recombinant bacteria infection group were significantly higher than those in the empty vector group,indicat-ing that Rv3641c could promote the intracellular surviv al of mycobacteria.In summary,the Rv3641c gene of M.tuberculosis can inhibit the host type I interferon response and promote the intracellular survival of M.tuberculosis,which provides a new idea for further explor-ing the immune escape function of M.tuberculosis and the discovery of new targets for anti-tuberculosis drugs.

Objective:To investigate the impact of different etiologies on the spatial distribution pattern of infarcts and the mapping pattern of focal symptoms in acute ischemic stroke (AIS) using a population-based standardized spatial analysis of MRI.Methods:This was a cross-sectional study. Clinical [age, sex distribution, admission National Institutes of Health Stroke Scale (NIHSS) score and 90-day modified Rankin Scale (mRS) score at discharge, etc.] and imaging data of 2 610 patients with AIS attending 9 Medical Centers from January 2015 to December 2021 were retrospectively analyzed. All patients were categorized into 1 718 cases of large artery atherosclerosis (LAA) type, 335 cases of cardioembolism (CE) type, and 557 cases of small artery occlusion (SAO) type according to TOAST typing. All patients underwent diffusion-weighted imaging, and the detected infarct lesions were segmented and aligned to the standardized space using artificial intelligence-assisted methods, and the spatial distribution frequency heatmaps of lesion locations in patients with different TOAST subtypes were plotted and compared with each other by χ2 test. Lesion-symptom image brain maps with different clinical symptoms were further plotted, and differences of lesion-symptom image relationships among different TOAST subtypes were observed and compared with each other by interaction effect. Results:In all patients, the favored sites of infarct lesions were the bilateral middle cerebral artery region in the anterior circulation and the occipital and brainstem regions in the posterior circulation. Compared with the LAA type, the CE type lesions were more likely to occur in the anterior cerebral artery region, the occipital lobe, and the cerebellum posterior, while the SAO type lesions were more likely to occur in the perforator artery supply area. The lesion-symptom mapping results showed that AIS patients with infarct lesions in the frontoparieto-temporal region in the presence of a left middle cerebral artery supply had higher admission NIHSS scores and higher discharge 90-day mRS scores for the LAA type than for the CE type( P<0.05); AIS patients with infarcted lesions in the brainstem region and some cerebellar regions in the presence of vertebrobasilar artery supply had higher admission NIHSS scores and higher discharge 90-day mRS scores for the CE type than for the LAA type( P<0.05). Conclusion:At the population level, brain mapping reveals specific infarct distribution patterns and differences in lesion-symptom mapping patterns of different etiologies AIS patients, providing imaging evidence for the understanding of AIS pathogenetic mechanisms and clinical management.

Objective To analyze the MRI imaging characteristics of brain metastases in non-small cell lung cancer(NSCLC)with different epidermal growth factor receptor(EGFR)mutation types and programmed cell death-ligand 1(PD-L1)expression,and to provide imaging diagnostic support for patients who can't undergo genetic and immunohistochemical testing.Methods A retrospec-tive selection was performed in 88 patients diagnosed with brain metastases of NSCLC,all patients were divided into EGFR mutation group and wild group according to the results of genetic testing,and patients with EGFR mutation group were divided into EGFR mutation with PD-L1 expression positive group and EGFR mutation with PD-L1 expression negative group according to whether the expression of PD-L1 was≥1％.The clinical data and MR image characteristics of brain metastases were compared in EGFR mutation group and wild group,as well as in EGFR mutation with PD-L1 expression positive group and EGFR mutation with PD-L1 expres-sion negative group.Results There were statistically significant differences in smoking history and intracranial symptoms between EGFR mutation group and wild group(P＜0.05).The edema diameter,edema index and enhancement ratio of EGFR mutation group and wild group were(0.67±1.10)cm,0.39±0.54,0.32±0.17 and(1.57±2.04)cm,1.05±1.21,0.53±0.27,respectively,and the differences were statistically significant(P＜0.05).There were 43 cases and 23 cases in EGFR mutation group and wild group with ≥2 metastases,respectively,and the difference was statistically significant(P＜0.05).Compared with＞60 years old,there were 15 patients(75％)of EGFR mutation with PD-L1 expres-sion positive in≤60 years old(P＜0.05).Conclusion Compared with EGFR wild patients,patients with EGFR mutation have more brain metastases(≥2),milder enhancement,less peritumoral edema,and fewer intracranial symptoms at initial diagnosis,and patients with EGFR mutation aged≤60 years are more likely to have PD-L1 expression positive.

This study was aimed at preliminarily investigating the genetic and antimicrobial resistance characteristics of Salmonella Alachua isolates through whole-genome analyses.Five Salmonella Alachua isolates from various sources(both hu-man and non-human)were collected and identified.Phenotype and serotype verification,antimicrobial susceptibility testing,and whole-genome sequencing were performed.Virulence genes,antimicrobial resistance genes,and plasmid replicons were predicted according to globally available Salmonella Alachua genomic data.A phylogenetic tree was constructed to explore the genetic background.The first report of Salmonella Alachua in China emerged in Shanghai in 2015,and patients presented pri-marily with diarrhea.The isolates have been found predominantly in the eastern and southern coastal regions.Among the five i-solates analyzed,four belonged to sequence type(ST)2061,and one belonged to ST1298.All isolates were susceptible to most commonly used clinical antibiotics.Whole-genome analyses revealed that two ST2061 strains carried the blaKPC-2 gene,and one ST1298 strain carried the fosA7 gene.Phylogenetic analysis of global Salmonella Alachua populations indicated that the ST2061 clone belonged to the C1 clade,which was closely related to strains from the UK,whereas the ST1298 clone was found in the C4 clade,a globally disseminated fosA 7-positive lineage.This study provides initial insights into the genetic and antimi-crobial resistance characteristics of Salmonella Alachua in China,highlighting the presence of strains carrying blaKPC-2 and fo-sA7 genes.These findings may provide a reference for future large-scale molecular epidemiological surveillance and source-trac-ing efforts,and they underscore the importance of enhanced resistance monitoring for Salmonella Alachua.

Aim To explore the in vitro anti-human triple-negative breast cancer(TNBC)effect and mech-anism of Austocystin R.Methods MTT assay was used to evaluate the anti-tumor potential of Austocystin R for various human tumor cells and normal cells.Flow cytometry was employed to evaluate the influence on cell cycle progression.mRFP-GFP-LC3 adenovirus transfection was used to evaluate the autophagic flux process.Western blot assay was used to verify the effect of Austocystin R on the expression of related pro-teins.Results The results showed that Austocystin R significantly inhibited the proliferation of multiple tumor cells in a dose-dependent manner,especially for the MDA-MB-231 cells with an IC50 of 1.45μmol·L-1.In addition,Austocystin R increased the protein expression of PTEN,p53,p-p53,p27,p21,and down-regulated the expression of p-PI3K,p-AKT and p-mTOR.Austocystin R can significantly increase the proportion of S-phase MDA-MB-231 cells,inhibit the expression of Cyclin D1,CDK4,CDK6,Rb,Cyclin B1 and CDK1,and promote the expression of Cyclin E1 and CDK2.Austocystin R can promote the autophagic flux process of MDA-MB-231 cells,promote the expres-sion of LC3 Ⅰ/Ⅱ,p-Beclin-1,p-ULK1,HMGB-1 and Atg 14 proteins,and inhibit the expression of Beclin-1,ULK1,p62,ATG 3,ATG 4B,ATG 5,ATG 7,ATG 12,ATG 13 and ATG 16L1 proteins.Conclusion Austo-cystin R can exhibit its anti-TNBC activity by inhibi-ting the PI3K/AKT/mTOR signaling pathway,blocking the cell cycle at the S phase and inducing autophagic cell death.

Abnormal signaling in the androgen receptor(AR)signaling pathway is critical for prostate cancer development and progression,so inhibition of AR activity through androgen deprivation therapy(ADT)is an important means to control the development of prostate cancer in the early stage.However,most patients relapse and develop castrate-resistant prostate cancer(CRPC)within 6～20 months.Sur-gery and radiotherapy are still the major treatments for CRPC,but there are adverse effects such as urina-ry symptoms and sexual dysfunction.The first and second generatiosn of novel AR inhibitors can effec-tively treat CRPC.However,resistance to these chemicals is inevitable,and thus many patients may ex-perience recurrence.Resistance to AR inhibitors mainly consists of AR mutations,splice variant forma-tion and amplification,which have been shown to play an important role in CRPC.Also,aberrant activa-tion of cyclin dependent kinase(CDKs)and epigenetic alterations(e.g.histone modifications and DNA methylation)have been reported to be associated with prostate cancer progression.Proteolysis targeting chimeras(PROTACs)have unique advantages in CRPC therapy by virtue of their unique mechanism of action,ability to target non-druggable proteins,and specific binding to targets.In this review,we sum-marize the development of PROTAC technology for the treatment of CRPC by targeting different structural domains of AR,CDKs and epigenetic markers,and discuss the future prospects and challenges of PRO-TACs in the therapeutic field.