关键词： 舒芬太尼   转录激活因子3   铁死亡   肝   再灌注损伤  

摘要： 目的: 本研究探讨了舒芬太尼预处理对大鼠肝缺血再灌注损伤(hepatic ischemia-reperfusion injury,HIRI)的保护作用及其潜在机制。 方法: 本研究通过建立SD大鼠肝缺血再灌注模型来探究舒芬太尼预处理对HIRI所起到的保护作用及其可能的相关机制。选取清洁级健康雄性SD大鼠18只,2-3月龄,体质量220～240 g,使用随机数字表法把大鼠分为3组(n=6):假手术组(Sham组)、肝缺血再灌注损伤组(HIRI组)、HIRI+舒芬太尼预处理组(HIRI+SF组)。Sham组仅在腹腔做与其他组同等大小的切口而不进行其他处理。HIRI组与HIRI+SF组制备70%肝缺血再灌注损伤大鼠模型。开腹前30 min,HIRI+SF组腹腔注射舒芬太尼3μg/kg,其余组注射等量生理盐水。再灌注24 h后,所有组的大鼠均通过眶后穿刺收集全血,离心后取上清液保存于液氮内,大鼠安乐死后采集肝脏标本。一部分新鲜肝脏组织放入4%多聚甲醛溶液中进行固定,固定24h以上后,进行脱水、包埋后制成石蜡切片备用;一部分新鲜肝脏组织放入电镜固定液内为后续进行透射电子显微镜的观察做准备;另一部分新鲜肝脏组织保存于液氮中备用。采用ELISA试剂盒测定丙氨酸氨基转氨酶(alanine aminotransferase,ALT)和天门冬氨酸氨基转移酶(aspartate aminotransferase,AST)浓度;光镜下观察各组肝组织病理学结果;采用免疫组化法、Western blot法及RT-q PCR法检测大鼠肝组织转录激活因子3(activated transcription factor 3,ATF3)的表达;Western blot法测定谷胱甘肽过氧化物酶4(recombinant glutathione peroxidase4,GPX4)表达水平;采用铁含量试剂盒测定各组肝细胞内铁含量的变化;透射电子显微镜观察各组肝细胞内线粒体及其他细胞器的形态。 结果: 1.舒芬太尼预处理对HIRI引起的肝损伤的影响。通过检测各组大鼠血清ALT、AST水平,HIRI组较Sham组ALT(P<0.01)、AST(P<0.0001)水平明显升高,而HIRI+SF组在经过舒芬太尼预处理之后显著逆转了这一作用(P<0.01,P<0.0001)。 2.舒芬太尼预处理对HIRI引起的肝脏病理学表现的影响。通过对比各组的肝脏病理切片,发现Sham组大鼠肝脏切片结构正常。相比之下,HIRI+SF组减轻了HIRI组中的肝窦损伤、充血炎症细胞浸润等变化,这提示舒芬太尼预处理改善了HIRI并逆转了组织学改变。 3.舒芬太尼预处理对ATF3、GPX4在肝组织中表达水平以及肝细胞内铁含量的影响。在免疫组织化学染色中,Sham组大鼠肝组织中ATF3表达明显。HIRI组ATF3表达较Sham组显著降低(P<0.0001),而经过舒芬太尼预处理的大鼠ATF3表达水平较HIRI组明显升高(P<0.01);在Western blot,HIRI组中的GPX4的表达较Sham组降低(P<0.0001),而经过舒芬太尼预处理后,肝组织中的GPX4表达水平有所升高(P<0.05);在Western blot及RT-PCR中缺血再灌注之后的大鼠ATF3蛋白表达水平较Sham组降低(P<0.0001),而在经过舒芬太尼预处理之后逆转了这一变化(P<0.01);与Sham组相比,HIRI组肝细胞中的铁含量明显升高(P<0.0001),而在经过舒芬太尼预处理之后,其肝细胞中的铁含量有所降低(P<0.05)。 4.舒芬太尼预处理对HIRI引起的铁死亡的影响(形态学方面)。我们通过透射电子显微镜对各组大鼠肝细胞内细胞器进行了观察,Sham组肝细胞轻微水肿,胞内细胞器大多结构尚可;而HIRI组肝细胞中度损伤,细胞膜局部破损,线粒体大多明显固缩、变小,膜内基质浓缩,电子密度高,嵴增宽。在经过舒芬太尼预处理之后,肝细胞损伤程度降低,细胞膜局部破损,胞内细胞器包括线粒体大多轻度固缩,线粒体小部分膜内基质浓缩。 结论: 舒芬太尼预处理可能通过提高ATF3的表达减轻HIRI铁死亡,而这一保护作用可能与其降低铁含量有关。

关键词： Diabetic cataract   oxidative stress   ferroptosis   immune infiltration   Mendelian randomization   Hspa5   Nfe2l2   Atf3  

摘要： BackgroundDiabetic cataract (DC) is a major cause of blindness, with its pathogenesis involving oxidative stress and ferroptosis, according to recent *** performed a Mendelian Randomization (MR) study using GWAS data to select SNPs and assess the causal link between diabetes and cataracts. DC datasets were analyzed for differential gene expression, WGCNA, and protein-protein interactions to identify key oxidative stress and ferroptosis genes. An SVM-RFE algorithm developed a diagnostic model, and ImmuCellAI analyzed immune infiltration *** analysis confirmed diabetes as a cataract risk factor and identified core genes related to oxidative stress and ferroptosis in DC. Four key genes (Hspa5/Nfe2l2/Atf3/Stat3) linked to both processes were discovered. Immune infiltration analysis revealed an imbalance associated with these *** functional interaction between oxidative stress and ferroptosis genes in DC is suggested, with a 4-gene model, indicating their potential as a 'bridge' in DC pathogenesis.

关键词： Sjogren's syndrome   Apigenin   Salivary gland epithelial cells   Ferroptosis  

摘要： Background: In Sjogren's ' s syndrome (SS)-an - an autoimmune disease characterized by dry mouth and eyes-salivary - salivary gland epithelial cells (SGECs) undergo ferroptosis, which disrupts their integrity and impairs saliva secretion. Apigenin, a phytoestrogen, is known to activate estrogen signalling and alleviate xerostomia in ovariectomized mice;however, its effect on SGEC survival and function in SS remains unclear. We hypothesized that apigenin alleviates SS symptoms and progression by inhibiting ferroptosis in SGECs and aimed to elucidate the underlying mechanism. Methods: Apigenin (50 mg/kg) was orally gavaged to non-obese diabetic (NOD)/LtJ female mice (SS model);changes in SS functional indicators were analyzed using mRNA sequencing and bioinformatic analyses of sub- mandibular glands. Interferon-gamma (IFN-gamma)-stimulated gamma )-stimulated SGECs were used to model SS in vitro;SGEC activity and aquaporin 5 (AQP5) expression were analyzed. Immunohistochemical staining, transmission electron microscopy, RT-qPCR, western blotting and other methods were used to verify the mechanisms. Results: Apigenin significantly increased salivary secretion and AQP5 expression while inhibiting ferroptosis and immune infiltration in NOD mouse submandibular glands. The oxidative stress gene ATF3 was upregulated and GPX4 was downregulated in NOD mice compared to that in control group (ICR mice);however, apigenin reversed this effect. IFN-gamma gamma treatment downregulated AQP5, SLC7A11, and GPX4 expression while promoting ATF3 expression and ferroptosis, which was mitigated by apigenin. ATF3 knockdown increased SLC7A11 and GPX4 expression, inhibiting SS and ferroptosis. Furthermore, apigenin inhibited ferroptosis in SGECs through ESR1 binding to ATF3. Conclusion: Apigenin alleviates SS by regulating SGEC ferroptosis via the ER alpha-regulated ATF3/SLC7A11 axis, highlighting its therapeutic potential in SS.

关键词： Neuronal oxidative stress   FTO   M(6)A modification   Cognitive dysfunction  

摘要： Excessive exposure to metals in daily life has been proposed as an environmental risk factor for neurological disorders. Oxidative stress is an inevitable stage involved in the neurotoxic effects induced by metals, nevertheless, the underlying mechanisms are still unclear. In this study, we used arsenic as a representative environmental heavy metal to induce neuronal oxidative stress and demonstrated that both in vitro and in vivo exposure to arsenic significantly increased the level of N6-methyladenosine (m6A) by down-regulating its demethylase FTO. Importantly, the results obtained from FTO transgenic mice and FTO overexpressed/knockout cells indicated that FTO likely regulated neuronal oxidative stress by modulating activating transcription factor 3 (ATF3) in a m(6)A-dependent manner. We also identified the specific m6A reader protein, YTHDC1, which interacted with ATF3 and thereby affecting its regulatory effects on oxidative stress. To further explore potential intervention strategies, cerebral metabolomics was conducted and we newly identified myo-inositol as a metabolite that exhibited potential in protecting against arsenic-induced oxidative stress and cognitive dysfunction. Overall, these findings provide new insights into the importance of the FTO-ATF3 signaling axis in neuronal oxidative stress from an m(6)A perspective, and highlight a beneficial metabolite that can counteract the oxidative stress induced by arsenic.

关键词： Osthole   Pancreatic cancer   Autophagy   ATF3   mTOR  

摘要： Pancreatic cancer (PC) is one of the most aggressive malignancies worldwide, and few effective therapeutics are available. Osthole (OST), a natural coumarin, has been proven to be a potential anticancer compound. In this study, we found that OST significantly inhibited PC growth both in vitro and in vivo. Notably, the anti-PC effect of OST is mediated by excessive autophagosome accumulation and consequent apoptosis in PC cells. Mechanistically, OST increased the number of autophagosomes via two pathways. First, OST induced autophagy initiation by suppressing the Akt/mTOR signaling pathway. Second, OST induced autophagic arrest by blocking autophagosome-lysosome fusion. Consistently, inhibition of autophagy initiation restored PC cell growth, whereas autophagic flux inhibitors exacerbated the antitumor effect of OST in PC cells, suggesting a cytotoxic role of OST-induced autophagosome accumulation. In addition, we found that OST upregulates the expression of activating transcription factor 3 (ATF3), resulting in inactivation of the Akt/mTOR signaling pathway and autophagy initiation in PC cells. ATF3 overexpression increased the activation of autophagy, and inhibition of ATF3 expression decreased autophagy. Taken together, our study provides new insights into the OST-induced growth inhibitory effect on PC cells, suggesting a promising potential therapeutic role of OST for PC treatment.

关键词： 激活转录因子3   ATF3   脂肪组织   脂质代谢  

摘要： 激活转录因子3(activating transcription factor3,ATF3)属于转录因子ATF/CREB(cAMP response element-binding)家族成员,参与葡萄糖代谢,免疫反应和肿瘤发生等生理过程,同时还参与动物脂肪组织的调节过程。本文主要总结近年来国内外关于ATF3基因在脂肪组织中的调控作用,为该基因在畜牧业肉用品种选育和基因功能研究提供理论基础。

关键词： Apoptosis   Necroptosis   Intestinal homeostasis   Mettl3   m6A modification   RIPK1  

摘要： Intestinal epithelial cells(IECs)are pivotal for maintaining intestinal homeostasis through self-renewal,proliferation,differentiation,and regulated cell *** apoptosis and necroptosis are recognized as distinct pathways,their intricate interplay remains *** this study,we report that Mettl3-mediated­m6A modification maintains intesti-nal homeostasis by impeding epithelial cell ***3 knockout induces both apoptosis and necroptosis in *** different modes of cell death with specific inhibitors unveils that RIPK1 kinase activity is critical for the cell death triggered by Mettl3 ***,this occurs via the­m6A-mediated transcriptional regulation of Atf3,a transcription factor that directly binds to Cflar,the gene encoding the anti-cell death protein *** inhibits RIPK1 activity,thereby suppressing downstream apoptotic and necroptotic ***,these find-ings delineate the essential role of the METTL3-ATF3-cFLIP axis in homeostatic regulation of the intestinal epithelium by blocking RIPK1 activity.

摘要： Reactivation of endogenous retroviruses (ERVs) has been proposed to be involved in aging. However, the mechanism of reactivation and contribution to aging and age-associated diseases is largely unexplored. In this study, we identified a subclass of ERVs reactivated in senescent cells (termed senescence-associated ERVs (SA-ERVs)). These SA-ERVs can be bidirectional transcriptionally activated by activating transcription factor 3 (ATF3) to generate double-stranded RNAs (dsRNAs), which activate the RIG-I/MDA5-MAVS signaling pathway and trigger a type I interferon (IFN-I) response in senescent fibroblasts. Consistently, we found a concerted increased expression of ATF3 and SA-ERVs and enhanced IFN-I response in several tissues of healthy aged individuals and patients with Hutchinson-Gilford progeria syndrome. Moreover, we observed an accumulation of dsRNAs derived from SA-ERVs and higher levels of IFN beta in blood of aged individuals. Together, these results reveal a previously unknown mechanism for reactivation of SA-ERVs by ATF3 and illustrate SA-ERVs as an important component and hallmark of aging.