查找使用阿拉丁产品的科研文献

Di-(2-ethylhexyl) phthalate exposure induces liver injury by promoting ferroptosis via downregulation of GPX4 in pregnant mice

Fan Zhang,Hualong Zhen,Hengshun Cheng,Fengying Hu,Yunfei Jia,Binbin Huang,Minmin Jiang

As one kind of endocrine disrupting chemical, di-(2-ethylhexyl) phthalate (DEHP) has been reported to cause liver dysfunction in epidemiological and experimental studies. Abnormal liver function in pregnancy is associated with adverse maternal and perinatal outcomes. Few studies have investigated the potential effect of gestational DEHP exposure on the liver in pregnant mice, and the underlying mechanisms remain unclear. In the present study, pregnant ICR mice were exposed to doses (0, 500, 1,000 mg/kg/day) of DEHP in the presence or absence of 5 mg/kg/day ferrostatin-1 (Fer-1, ferroptosis inhibitor) by oral gavage from gestation day 4 to day 18. HepG2 cells were exposed to different doses of monoethylhexyl phthalate (MEHP, a major metabolite of DEHP) in vitro . Hepatic function and pathologic changes were observed. Oxidative stress, iron metabolism, and ferroptosis-related indicators and genes were evaluated both in vivo and in vitro . The results showed that gestational DEHP exposure induced disordered liver function and hepatocyte morphology changes in pregnant mice, along with increased malondialdehyde (MDA) and Fe 2+ content and decreased glutathione (GSH) levels. The expression levels of the selected ferroptosis-related genes Slc7a11 , Gpx4 , and Nfr2 were significantly decreased, and Ptgs2 and Lpcat3 were significantly increased. Notably, Fer-1 attenuated DEHP-induced liver injury and ferroptosis. Furthermore, MEHP exhibited a synergistic effect with RSL3 (a GPX4 inhibitor) in promoting ferroptosis in vitro . Taken together, the results demonstrated that DEHP induced liver injury and ferroptosis in pregnant mice, probably by inhibiting the GPX4 pathway through lipid peroxidation and iron accumulation.

Non-canonical role of UCKL1 on ferroptosis defence in colorectal cancer

Weili Wu,Yingying Zhao,Baifu Qin,Xin Jiang,Chuyue Wang,Rong Hu,Rui Ma,Mong-Hong Lee,Huanliang Liu,Kai Li,Ping Yuan

Guiding bar motif of thioredoxin reductase 1 modulates enzymatic activity and inhibitor binding by communicating with the co-factor FAD and regulating the flexible C-terminal redox motif

Wuyang Shi,Shibo Sun,Haowen Liu,Yao Meng,Kangshuai Ren,Guoying Wang,Minghui Liu,Jiaqi Wu,Yue Zhang,Huang Huang,Meiyun Shi,Weiping Xu,Qiang Ma,Bingbing Sun,Jianqiang Xu

Thioredoxin reductase (TXNRD) is a selenoprotein that plays a crucial role in cellular antioxidant defense. Previously, a distinctive guiding bar motif was identified in TXNRD1, which influences the transfer of electrons. In this study, utilizing single amino acid substitution and Excitation-Emission Matrix (EEM) fluorescence spectrum analysis, we discovered that the guiding bar communicates with the FAD and modulates the electron flow of the enzyme. Differential Scanning Fluorimetry (DSF) analysis demonstrated that the aromatic amino acid in guiding bar is a stabilizer for TXNRD1. Kinetic analysis revealed that the guiding bar is vital for the disulfide reductase activity but hinders the selenocysteine-independent reduction activity of TXNRD1. Meanwhile, the guiding bar shields the selenocysteine residue of TXNRD1 from the attack of electrophilic reagents. We also found that the inhibition of TXNRD1 by caveolin-1 scaffolding domain (CSD) peptides and compound LCS3 did not bind to the guiding bar motif. In summary, the obtained results highlight new aspects of the guiding bar that restrict the flexibility of the C-terminal redox motif and govern the transition from antioxidant to pro-oxidant.

Hinokitiol-iron complex is a ferroptosis inducer to inhibit triple-negative breast tumor growth

Zhao Hongting,Zhang Meng,Zhang Jinghua,Sun Zichen,Zhang Wenxin,Dong Weichen,Cheng Chen,Yao Yongzhong,Li Kuanyu

Background Ferroptosis is a unique cell death, dependent on iron and phospholipid peroxidation, involved in massive processes of physiopathology. Tremendous attention has been caught in oncology, particularly for those therapy-resistant cancers in the mesenchymal state prone to metastasis due to their exquisite vulnerability to ferroptosis. Therefore, a therapeutical ferroptosis inducer is now underway to be exploited.Results A natural compound, hinokitiol (hino), has been considered to be an iron chelator. We have a novel finding that hino complexed with iron to form Fe(hino)3 can function as a ferroptosis inducer in vitro. The efficiency, compared with the same concentration of iron, increases nearly 1000 folds. Other iron chelators, ferroptosis inhibitors, or antioxidants can inhibit Fe(hino)3-induced ferroptosis. The complex Fe(hino)3 efficacy is further confirmed in orthotopic triple-negative breast cancer (TNBC) tumor models that Fe(hino)3 significantly boosted lipid peroxidation to induce ferroptosis and significantly reduced the sizes of TNBC cell-derived tumors. The drug’s safety was also evaluated, and no detrimental side effects were found with the tested dosage.Conclusion sWhen entering cells, the chelated iron by hinokitiol as a complex Fe(hino)3 is proposed to be redox-active to vigorously promote the production of free radicals via the Fenton reaction. Thus, Fe(hino)3 is a ferroptosis inducer and, therapeutically, exhibits anti-TNBC activity.

A potent GPX4 degrader to induce ferroptosis in HT1080 cells

Haoze Song,Jing Liang,Yuanyuan Guo,Yang Liu,Kuiru Sa,Guohong Yan,Wen Xu,Wei Xu,Lixia Chen,Hua Li

Glutathione peroxidase 4 (GPX4) is the most promising target for inducing ferroptosis . GPX4-targeting strategies primarily focus on inhibiting its activity or adjusting its cellular level. However, small inhibitors have limitations due to the covalent reactive alkyl chloride moiety, which could lead to poor selectivity and suboptimal pharmacokinetic properties. Herein, we designed and synthesized a series of proteolysis targeting chimeras (PROTACs) by connecting RSL3, a small molecule inhibitor of GPX4, with six different ubiquitin ligase ligands. As a highly effective degrader, compound 18a is a potent degrader (DC 50, 48h  = 1.68 μM, D max, 48h  = 85 %). It also showed an obvious anti-proliferative effect with the IC 50 value of 2.37 ± 0.17 μM in HT1080. Mechanism research showed that compound 18a formed a ternary complex with GPX4 and cIAP and induced the degradation of GPX4 through the ubiquitin-proteasome system pathway. Furthermore, compound 18a also induced the accumulation of lipid peroxides and mitochondrial depolarization, subsequently triggering ferroptosis. Our work demonstrated the practicality and efficiency of the PROTAC strategy and offered a promising avenue for designing degraders to induce ferroptosis in cancer cells.

Cycloheptylprodigiosin from marine bacterium Spartinivicinus ruber MCCC 1K03745T induces a novel form of cell death characterized by Golgi disruption and enhanced secretion of cathepsin D in Non-small cell lung cancer cell lines

Xiaosi Lin,Le Dong,Qing Miao,Zhaobin Huang,Fang Wang

Prodiginines have been studied extensively for their anticancer activity, however, the majority of the research has focused on prodigiosin. In this study, cycloheptylprodigiosin (S-1) is extracted from marine bacterium Spartinivicinus ruber MCCC 1K03745 T , and its anticancer property was investigated. It exhibits remarkable cytotoxicity against a panel of human lung cancer cell lines, with the IC 50 values ranging from 84.89 nM to 661.2 nM. After 6 hours of treatment, S-1 gradually accumulates on mitochondria and lysosomes. While lower doses of S-1 induce cell cycle arrest, treatment with higher doses results in cell death in apoptotic independent manner in both NCI-H1299 and NCI-H460 cell lines. Interestingly, treatment with S-1 leads to the accumulation of LC3B-II via pathways that vary among different cell lines. In addition to its role as an autophagy inhibitor, S-1 also promotes autophagy initiation as demonstrated by the increment of EGFP fragment in the EGFP-LC3 degradation assay, however, inhibition of autophagy does not rescue cells from death induced by S-1. Mechanistically, S-1 impairs autophagic flux through disrupting acidic lysosomal pH and blocking the maturation of cathepsin D. Moreover, treatment with S-1 enhanced secretion of both pro- and mature forms of cathepsin D, coincident with disintegration of trans-Golgi network. Interestingly, S-1 does not induce ferroptosis, pyroptosis or necroptosis in NCI-H1299 cells. However, treatment of NCI-H460 cells with S-1 induces methuosis, which can be suppressed by Rac1 inhibitor EHT 1864. Our data demonstrate that S-1 is an effective anticancer agent with potential therapeutic application.