摘要: As major somatic cells in the testis, Sertoli cell development is precisely regulated by numerous factors, and aberrant development of these cells is associated with male reproductive diseases. JNK signalling is evolutionarily conserved and involved in multiple critical biological processes. Here, we found that the double knockout of Jnk1 and Jnk2 resulted in aberrant localisation of Sertoli cells at early developmental stages, with most Sertoli cells being lost at later stages. Further studies revealed that the inactivation of JNK signalling caused polarity loss in Sertoli cells. In vitro-cultured Jnk1/2-DKO Sertoli cells exhibited a senescence-associated phenotype. Mechanistic studies demonstrate that JNK signalling is likely involved in establishing Sertoli cell polarity by regulating the expression of TGF-beta 2, mediated by c-Jun. The senescence of Sertoli cells in JNKs-deficient mice is caused by aberrant proteolysis of P27(KIP1), mediated by c-Myc. This study demonstrates the role of JNK signalling in Sertoli cell development and functional maintenance, which may also represent an aetiology of male infertility in humans.

摘要: Estrogen has been implicated in multiple biological processes, but the variation underlying estrogen-mediated primordial follicle (PF) formation remains unclear. Here, we show that 17 beta-estradiol (E2) treatment of neonatal mice led to the inhibition of PF formation and cell proliferation. Single-cell RNA sequencing (scRNA-seq) revealed that E2 treatment caused significant changes in the transcriptome of oocytes and somatic cells. E2 treatment disrupted the synchronised development of oocytes, pre-granulosa (PG) cells and stromal cells. Mechanistically, E2 treatment disrupted several signalling pathways critical to PF formation, especially down-regulating the Kitl and Smad1/3/4/5/7 expression, reducing the frequency and number of cell communication. In addition, E2 treatment influenced key gene expression, mitochondrial function of oocytes, the recruitment and maintenance of PG cells, the cell proliferation of somatic cells, as well as disordered the ovarian microenvironment. This study not only revealed insights into the regulatory role of estrogen during PF formation, but also filled in knowledge of dramatic changes in perinatal hormones, which are critical for the physiological significance of understanding hormone changes and reproductive protection. The work first presented the transcriptional programmes of primordial follicle (PF) formation regulated by 17 beta-estradiol in neonatal mouse ovaries, which not only revealed insights into the regulatory role of estrogen during PF formation, but also filled in knowledge of dramatic changes in perinatal hormones, which are critical for the physiological significance of understanding hormone changes and reproductive protection. image

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摘要: Non-alcoholic fatty liver disease (NAFLD) has emerged as the primary risk factor for hepatocellular carcinoma (HCC), owing to improved vaccination rates of Hepatitis B and the increasing prevalence of metabolic syndrome related to obesity. Although the importance of innate and adaptive immune cells has been emphasized, the malignant transformation of hepatocytes and their intricate cellular network with the immune system remain unclear. The study incorporated four single-cell transcriptomic datasets of liver tissues covering healthy and NAFLD-related disease status. To identify the subsets and functions of hepatocytes and macrophages, we employed differential composition analysis, functional enrichment analysis, pseudotime analysis, and scenic analysis. Furthermore, an experimental mouse model for the transformation of nonalcoholic steatohepatitis into hepatocellular carcinoma was established for validation purposes. We defined CYP7A1(+) hepatocytes enriched in precancerous lesions as 'Transitional Cells' in the progression from NAFLD to HCC. CYP7A1(+) hepatocytes upregulated genes associated with stress response, inflammation and cancer-associated pathways and downregulated the normal hepatocyte signature. We observed that hypoxia activation accompanied the entire process of inflammation-cancer transformation. Hepatocyte-derived HIF1A was gradually activated during the progression of NAFLD disease to adapt to the hypoxic microenvironment and hepatocytes under hypoxic environment led to changes in the metabolism, proliferation and angiogenesis, promoting the occurrence of tumours. Meanwhile, hypoxia induced the polarization of RACK1(+) macrophages that enriched in the liver tissues of NASH towards immunosuppressed TREM2(+) macrophages. Moreover, immunosuppressive TREM2(+) macrophages were recruited by tumour cells through the CCL15-CCR1 axis to enhance immunosuppressive microenvironment and promote NAFLD-related HCC progression. The study provides a deep understanding of the development mechanism of NAFLD-related HCC and offers theoretical support and experimental basis for biological targets, drug research, and clinical application.

摘要: Epigenetic reprogramming during fertilization and somatic cell nuclear transfer (NT) is required for cell plasticity and competent development. Here, we characterize the epigenetic modification pattern of H4K20me3, a repressive histone signature in heterochromatin, during fertilization and NT reprogramming. Importantly, the dynamic H4K20me3 signature identified during preimplantation development in fertilized embryos differed from NT and parthenogenetic activation (PA) embryos. In fertilized embryos, only maternal pronuclei carried the canonical H4K20me3 peripheral nucleolar ring-like signature. H4K20me3 disappeared at the 2-cell stage and reappeared in fertilized embryos at the 8-cell stage and in NT and PA embryos at the 4-cell stage. H4K20me3 intensity in 4-cell, 8-cell, and morula stages of fertilized embryos was significantly lower than in NT and PA embryos, suggesting aberrant regulation of H4K20me3 in PA and NT embryos. Indeed, RNA expression of the H4K20 methyltransferase Suv4-20h2 in 4-cell fertilized embryos was significantly lower than NT embryos. Knockdown of Suv4-20h2 in NT embryos rescued the H4K20me3 pattern similar to fertilized embryos. Compared to control NT embryos, knockdown of Suv4-20h2 in NT embryos improved blastocyst development ratios (11.1% vs. 30.5%) and full-term cloning efficiencies (0.8% vs. 5.9%). Upregulation of reprogramming factors, including Kdm4b, Kdm4d, Kdm6a, and Kdm6b, as well as ZGA-related factors, including Dux, Zscan4, and Hmgpi, was observed with Suv4-20h2 knockdown in NT embryos. Collectively, these are the first findings to demonstrate that H4K20me3 is an epigenetic barrier of NT reprogramming and begin to unravel the epigenetic mechanisms of H4K20 trimethylation in cell plasticity during natural reproduction and NT reprogramming in mice.

摘要: The appropriate allocation of nutrients between the mother and the fetus during mammalian pregnancy primarily depends on a healthy placenta. Fetal growth restriction (FGR) is frequently associated with inadequate maternal nutrition supply and impaired placental function. The precise mechanisms linking maternal nutrient deficiency to compromised fetal and placental development remain largely elusive. In this study, we conducted an in-depth analysis by integrating single-cell/single-nucleus RNA sequencing data from human and mouse placentas along with transcriptomic data from FGR placenta, identifying the GAB1 (GRB2-associated binding protein 1) gene as a potential mediator of dysregulated maternal-fetal exchange, thereby affecting fetal growth. Using a mouse model, we demonstrated that food restriction significantly impeded fetal growth and disrupted placental labyrinth development. Through an in vitro trophoblast differentiation model, we revealed that nutritional restriction impaired GAB1 stability via LC3-interacting region (LIR) motif-mediated selective autophagic degradation, thereby hindering GAB1-MAPK signalling-enhanced trophoblast syncytialisation. These findings elucidate the mechanisms by which placental GAB1 links maternal nutrition status with fetal growth and suggest potential therapeutic strategies for managing pregnancy complications such as FGR.

摘要: Extrachromosomal circular DNA (eccDNA) has emerged as a critical area of cancer research due to its ubiquitous presence in tumour cells and significant role in tumorigenesis, progression and drug resistance. Recent studies demonstrate that eccDNA promotes cancer progression by influencing genomic instability, amplifying oncogenes, regulating gene expression and enhancing tumour cell adaptability to adverse conditions. While the precise mechanisms underlying eccDNA formation and its biological functions remain unclear, its potential applications in cancer diagnosis, prognosis and targeted therapy are gaining increasing recognition. This review summarises the latest advancements in eccDNA research, highlighting its potential as both a biomarker and a therapeutic target. Additionally, it emphasises the translational potential of eccDNA in clinical diagnostics and personalised treatment strategies, offering new perspectives for future cancer research and innovative therapies.

摘要: Aromatase inhibitors are effective in treating hormone receptor-positive breast cancer, particularly in postmenopausal women. However, the challenges of inconsistent dissolution, variable absorption and side effects with oral administration persist. To address these issues, transdermal delivery has emerged as a viable alternative. In our study, we have developed nanoemulsion-based transdermal creams containing third-generation aromatase inhibitors Exemestane (EXE) or Letrozole (LE) and evaluated their toxicity, anti-tumour effects and androgenic potency using preclinical models including Bama minipigs, DMBA-induced breast cancer rats and orchidectomized male rats. The results of our study are significant, suggesting that both creams effectively penetrated the skin, demonstrating an impressive anti-breast cancer effect. Importantly, EXE cream had no organ toxicity at the tested dose, providing a reassuring safety profile for its use. In contrast, LE cream displayed reversible toxicity from drug molecule itself in animals at the given dose, dissipating after 3 weeks of withdrawal and recovery. This study establishes a solid foundation for the safe clinical use of third-generation aromatase inhibitors. It highlights transdermal creams as a promising drug delivery carrier for administering them. The formulations of both steroidal and non-steroidal aromatase inhibitors in transdermal creams have demonstrated the ability to permeate the skin and effectively impede breast cancer progression. In particular, steroidal aromatase inhibitor cream exhibited negligible animal toxicity and moderate androgenic activity. In contrast, non-steroidal aromatase inhibitor cream displayed some reversible toxicity.image

摘要: Renal fibrosis is a prevalent pathological alteration that occurs throughout the progression of primary and secondary renal disorders towards end-stage renal disease. As a complex and irreversible pathophysiological phenomenon, it includes a sequence of intricate regulatory processes at the molecular and cellular levels. Exosomes are a distinct category of extracellular vesicles that play a crucial role in facilitating intercellular communication. Multiple pathways are regulated by exosomes produced by various cell types, including tubular epithelial cells and mesenchymal stem cells, in the context of renal fibrosis. Furthermore, research has shown that exosomes present in bodily fluids, including urine and blood, may be indicators of renal fibrosis. However, the regulatory mechanism of exosomes in renal fibrosis has not been fully elucidated. This article reviewed and analysed the various mechanisms by which exosomes regulate renal fibrosis, which may provide new ideas for further study of the pathophysiological process of renal fibrosis and targeted treatment of renal fibrosis with exosomes. Multiple pathways are regulated by exosomes produced by various cell types, including tubular epithelial cells and mesenchymal stem cells, in the context of renal fibrosis. The study of exosomes will explore their potential in translational medicine and provide new ideas and ways for creating effective clinical treatment strategies. image

摘要: The biogenesis of exosomes that mediate cell-to-cell communication by transporting numerous biomolecules to neighbouring cells is an essential cellular process. The interaction between the transmembrane protein syndecan-4 (SDC4) and cytosolic protein syntenin plays a key role in the biogenesis of exosomes. However, how the relatively weak binding of syntenin to SDC4 efficiently enables syntenin sorting for packaging into exosomes remains unclear. Here, we demonstrate for the first time that SDC4 can undergo liquid-liquid phase separation (LLPS) to form condensates both in vitro and in the cell membrane and that, the SDC4 cytoplasmic domain (SDC4-CD) is a key contributor to this process. The phase separation of SDC4 greatly enhances the recruitment of syntenin to the plasma membrane (PM) despite the weak SDC4-syntenin interaction, facilitating syntenin sorting for inclusion in exosomes. Interestingly, phosphorylation at the only serine (179) in the SDC4-CD (Ser179) disrupts SDC4 LLPS, and inhibited phosphorylation or dephosphorylation restores the SDC4 LLPS to promote its recruitment of syntenin to the PM and syntenin inclusion into exosomes. This research reveals a novel phosphorylation-regulated phase separation property of SDC4 in the PM through which SDC4 efficiently recruits cytosolic syntenin and facilitates the biogenesis of exosomes, providing potential intervention targets for exosome-mediated biomedical events. This research uncovers a novel phosphorylation-regulated phase separation property of SDC4 on the PM by which SDC4 realizes efficient recruitment of cytosolic syntenin and thereby facilitates the biogenesis of exosomes, providing potential intervention targets for exosome-involved biomedical events. image