Acta Biochimica et Biophysica Sinica

Recent evidence indicates that ferroptosis is implicated in the pathophysiology of various liver diseases; however, the mechanism of ferroptosis regulation in the liver is poorly understood. Here, using the whole-genome screening approach, we identified 7-dehydrocholesterol reductase (DHCR7), the terminal enzyme of cholesterol biosynthesis, as a novel regulator of ferroptosis in hepatocytes. Genetic and pharmacological inhibition (with AY9944) of DHCR7 suppressed lipid peroxidation and ferroptosis in human hepatocellular carcinoma Huh-7 cells. DHCR7 inhibition increased its substrate, 7-dehydrocholesterol (7-DHC), and extrinsic 7-DHC supplementation in turn suppressed ferroptosis. On the other hand, cholesterol deprivation had no effect on ferroptosis. A 7-DHC-derived oxysterol metabolite, 3{beta},5-dihydroxycholest-7-en-6-one (DHCEO), was increased by a ferroptosis inducer RSL-3 in DHCR7-deficient cells, suggesting that the ferroptosis-suppressive effect of DHCR7 inhibition was driven by intracellular 7-DHC as a radical scavenger. While extrinsic 7-DHC supplementation suppressed ferroptosis in various cancer cells, pharmacological DHCR7 inhibition by AY9944 showed cell-type specific effects, which could be explained by high DHCR7 expression in Huh-7 cells. We further showed that AY9944 suppressed ferroptosis in murine primary hepatocytes in vitro and systemic administration of AY9944 inhibited hepatic ischemia-reperfusion injury in vivo. These findings provide new insights into the regulatory mechanism of liver ferroptosis and suggest that DHCR7 inhibition is a potential therapeutic option for ferroptosis-related liver diseases.

Lowering proteotoxicity is a potentially powerful approach for the treatment of neurological disorders, such as Parkinsons disease. The unfolded protein response (UPR) is a major mechanism that preserves the network maintaining cellular proteostasis. In the present study, we developed the screening strategy to discover compounds that significantly enhanced the activation of mitochondrial UPR (UPRmt) through increasing cardiolipin content. We identified that ginsenoside Rg3 (Rg3) increased cardiolipin depending on cardiolipin synthase 1 (CRLS1) in both worms and in human neural cells. Using LiP-SMap (limited proteolysis-mass spectrometry) strategy, we identified GRB2 (growth factor receptor bound protein 2) as a direct target of Rg3 in human neural cells. Rg3 enhances the binding between GRB2 and TRKA, that transduces signals via phosphrorylation of ERK. We provide bioinformatic and experimental evidence that EVI1, the critical oncogenic transcriptional regulator in leukemia, binds to CRLS1 promoter region and stimulated CRLS1 expression and subsequently increased cardiolipin content in the presence of Rg3. In a Parkinsons disease mouse model, Rg3 restores motor function by protecting nigral dopaminergic neurons dependent on Grb2. Our data recapitulate the TRKA-GRB2-EVI1-CRLS1 axis in maintaining proteostasis in Parkinsons disease via UPRmt.

Ferroptosis is a form of regulated cell death characterized by excessive iron-dependent lipid peroxidation. Ferroptosis can be induced in cultured cells by exposure to certain chemicals (e.g., erastin and RSL3). Recently it was shown that protein disulfide isomerase (PDI) is a mediator of chemically-induced ferroptosis and also a target for ferroptosis protection. In this study, we find that bazedoxifene (BAZ), a selective estrogen receptor modulator with reported neuroprotective actions in humans, can inhibit PDI function and also strongly protect against chemically-induced ferroptosis in cultured neuronal cells. We find that BAZ can directly bind to PDI in vitro and in intact neuronal cells, and also can inhibit PDIs catalytic activity. Computational modeling analysis reveals that BAZ forms a hydrogen bond with PDI-His256. Inhibition of PDI by BAZ markedly reduces nNOS and iNOS dimerization and NO accumulation, which have recently been shown to play a crucial role in mediating chemically-induced ferroptosis. In addition, the direct antioxidant activity of BAZ may also partially contribute to its protective effect against chemically-induced ferroptosis. Behavioral analysis shows that mice treated with BAZ are strongly protected against kainic acid-induced memory deficits and hippocampal neuronal damage in vivo. In conclusion, the results of this study demonstrate that BAZ is an inhibitor of PDI and can strongly prevent chemically-induced ferroptosis in hippocampal neurons both in vitro and in vivo. These observations offer a novel, estrogen receptor-independent mechanism for the recently-reported neuroprotective actions of BAZ in humans. SIGNIFICANCE STATEMENTFerroptosis is an iron- and lipid peroxidation-dependent form of regulated cell death. Recent evidence has shown that protein disulfide isomerase (PDI) is an important mediator of chemically-induced ferroptosis and also a new target for ferroptosis protection. We find that bazedoxifene is an inhibitor of PDI, which can strongly protect against chemically-induced ferroptotic neuronal death in vitro and in vivo. Additionally, the molecular mechanism of PDI{square}bazedoxifene binding interaction is defined. This work provides evidence for an estrogen receptor-independent, PDI-mediated mechanism of neuroprotection by bazedoxifene.

The activation of hepatic stellate cells (HSCs) is the central link in the occurrence and development of liver fibrosis. Our previous studies showed that autophagy promotes HSCs activation and ultimately accelerates liver fibrosis. Unc-51-like autophagy activating kinase 1 (ULK1) is an autophagic initiator in mammals and N6-methyladenosine (m6A) modification is closely related to autophagy. In this study, we find that m6A demethylase fat mass and obesity-associated protein (FTO) is upregulated during HSCs activation and bile duct ligation (BDL)-induced hepatic fibrosis, which is the m6A methylase with the most significant difference in expression. Importantly, we identify that FTO overexpression aggravates HSCs activation and hepatic fibrosis via autophagy. Mechanistically, compared with other autophagy-related genes, ULK1 is the target of FTO due to FTO mainly mediates the m6A demethylation of ULK1 and upregulates its expression, thereby enhancing autophagy and activation of HSCs. Noteworthy, m6A reader YTH domain-containing protein 2 (YTHDC2) decreases ULK1 mRNA level via recognizing the m6A binding site and ultimately inhibits autophagy and activation of HSCs. Taken together, our findings highlight m6A-dependent ULK1 as an essential regulator of HSCs autophagy and reveal ULK1 as a novel potential therapeutic target for hepatic fibrosis treatment. Graphical Abstractm6A demethylases FTO promoted autophagy via recognizing the ULK1 m6A binding site, thus triggering HSCs activation, and eventually leading to liver fibrosis. In this process, YTHDC2 participated in the translation of ULK1. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/584975v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@4fdd01org.highwire.dtl.DTLVardef@136791forg.highwire.dtl.DTLVardef@149f448org.highwire.dtl.DTLVardef@44ca9c_HPS_FORMAT_FIGEXP M_FIG C_FIG

Glutamine metabolism plays a central role in regulating uncontrolled growth of tumor (exhibiting glutamine addiction) by modulating bioenergetics and redox homeostasis, as well as serving as a precursor for biomass synthesis. Thus, limiting its availability is becoming a potential therapeutic strategy. Since Nrf1 is an indispensable determinant of mitochondrial homeostasis through the integration of a multilevel regulatory network for redox balance, no reports on the regulatory role of Nrf1 in glutamine addiction emerged hitherto. In this study, we found that glutamine deprivation leads to mitochondrial morphological and functional damage, reduced GSH levels, increased ROS, and rapid death of Nrf1-knockout HepG2 cells. A series of further experiments revealed that such rapid death of Nrf1-deficient cells from glutamine deprivation is caused by different ways. Loss of Nrf1 results in an obvious enhancement of glycolysis and fatty acid synthesis, leading to extensive catabolism of glutamine into -KG within mitochondria; the -KG reverses TCA cycles to generate citrate, which exits to the cytosol for fatty acid synthesis. Simultaneously, increased expression of xCT together with decreased expression of GLUL leads to elevated extracellular efflux of glutamate and reduced capacity for glutamine synthesis. These factors intensify glutamine addiction of Nrf1-null cells, with reducing GSH synthesis and increasing ROS levels due to dysfunctional mitochondria, ultimately leading to enhanced cell death upon glutamine deprivation. Overall, such insights into Nrf1s role in cancer glutamine metabolism are conducive to developing much specific preventive and therapeutic strategies by precision Nrf1-targeting anti-tumorigenesis.

Pregnancy is a very complex and delicate process, inflammation in early pregnancy may result in pregnancy loss or defective implantation. Melatonin, mainly produced from the pineal body, which exerts several pharmacological effects. N6-methyladenosine (m6A) is the most prevalent modification of eukaryotic mRNA. The aim of this study was to investigate the association between melatonin and m6A during pregnancy and elaborate the underlying protective mechanism of melatonin during pregnancy. In vitro, melatonin was found to alleviated LPS-induced reductions in the number of implantation sites. Besides, melatonin was found to alleviate the activation of inflammation, autophagy and apoptosis pathways. In vitro studies demonstrated that melatonin regulated several downstream pathways in an m6A-dependent manner via melatonin receptor MTNR1B. Our findings revealed the important roles of m6A in the establishment of pregnancy and discovered a new mechanism of how melatonin protects pregnancy.

Acute kidney injury following acute pancreatitis (AP-AKI) is one of the most fatal complications caused by acute pancreatitis (AP). Extracellular vesicles (EVs) in circulating blood are believed to be crucial to the process of AP-AKI, but the mechanisms are still unclear. In this study, we first constructed an AP-AKI rat model by retrograde sodium taurocholate through the pancreatic duct and then injected circulating blood-derived EVs into AP-AKI rats. Measurements of peripheral blood creatinine and urea nitrogen levels showed that EVs could add to kidney injury in AP-AKI rats. By analyzing the levels of renal Fe2+, cyclooxygenase 2 (COX-2), malondialdehyde (MDA), and glutathione peroxidase 4 (GPX4), we also found that extracted EVs could aggravate renal tubular ferroptosis in AP-AKI rats. Using high-throughput sequencing, we screened for high expression of EV miR-150-3P in AP-AKI patients. In vitro, we found that overexpressed miR-150-3P can influence MDA, Fe2+, lipid peroxide and GSH levels in HK-2 cells and ultimately aggravate ferroptosis. Next, through a dual-luciferase assay, we confirmed that miR-150-3p could exacerbate ferroptosis by directly targeting ferritin heavy chain 1 (FTH1). Finally, in AP-AKI rats, we again demonstrated that overexpression of miR-150-3P exacerbated renal ferroptosis through the miR-150-3P/FTH1 axis. Collectively, these findings provide new avenues to explore the mechanisms of the onset and exacerbation of AP-AKI.

Hepatitis B virus infection could result in male infertility by inhibiting sperm function and viability. Sertoli cell death contributes to spermatogenesis impairment, which is associated with sperm defects and dysfunction. Ferroptosis-mediated cell death of Sertoli cells was found to contribute to spermatogenesis disorder and poor sperm quality. However, the effects of hepatitis B virus infection on ferroptosis of Sertoli cells remain to be elucidated. Human Sertoli cells were cultured in vitro with 25, 50, and 100 mg/mL of hepatitis B virus surface protein for 48 hours. Cell viability was measured with CCK-8. Levels of glutathione, malondialdehyde, iron, and m6A in human Sertoli cells were determined. Lipid peroxidation was assessed using C11-BODIPY. Luminescence analysis was performed to detect the binding of METTL3 and 3{cents}-UTR of TRIM37 containing the m6A motifs. Immunoprecipitation was applied to determine the relationship between TRIM37 and GPX4. qPCR and immunoblotting were performed to measure mRNA and protein levels. Hepatitis B virus surface protein exposure significantly increased TRIM37 expression, malondialdehyde level, and ferroptosis, and decreased cell viability and glutathione level of human Sertoli cells. TRIM37 silencing inhibits the effect of HBs exposure-regulated cell viability and ferroptosis in human Sertoli cells. TRIM37 inhibits GPX4 expression through ubiquitination. GPX4 overexpression inhibits the effect of TRIM37 on cell viability and ferroptosis in human Sertoli cells. Administration of ferroptosis inhibitor recovers the cell viability decreased by TRIM37. Mechanism study showed HBs increases the level of TRIM37 3-UTR m6A by promoting the expression of METTL3, and the binding of m6A reader IGF2BP2 and TRIM37 3-UTR promotes the stability of TRIM37 mRNA.HBs inhibit Sertoli cell viability by promoting ferroptosis of Sertoli cells through TRIM37-mediated ubiquitination of GPX4. The findings highlight the importance of TRIM37/GPX4 signaling in the ferroptosis of Sertoli cells.

Cyclic GMP-AMP synthase (cGAS) serves as a DNA sensor for recognizing and binding microbial or self-DNA molecules in cells. Upon binding DNA, cGAS produces the second messenger cGAMP to activate the stimulator of interferon genes (STING), which mediates the expression of type 1 interferons (IFN-I) and other cytokines. cGAS-STING-mediated signal pathway plays an important role in innate immune reaction against microbial infections as well as autoimmunity, tumor immunology, and cellular senescence. During this process, cGAS regulates DNA damage repair and induces STING-mediated NF-{kappa}B and MAPK signal pathways in autophagy and lysosome-dependent cell apoptosis. However, the molecular mechanisms of cGAS-STING-mediated autophagy still need to be explored. Here, we found that cGAS-STING promotes autophagy by influencing multiple autophagy-related signal pathways: First, cGAS-STING promotes autophagy by inhibiting the mTOR signaling pathway; Second, cGAS-STING affects autophagy by regulating autophagy-related proteins that are also involved in cGAS-STING-mediated IFN-I and NF-{kappa}B signaling pathways; Third, the Bcl2 can interact with cGAS and STING to induce cGAS-STING-mediated up-regulation of IFN-I signaling pathway and down-regulation of NF-{kappa}B. In addition, we also found that USP19 can significantly reduce the K11-linked ubiquitination of STING in the process of autophagy. Our findings unveiled the functional role and the mechanism of cGAS-STING signaling in regulating autophagy.

The dysregulation of transcription factors is widely associated with tumorigenesis. As the most well-defined transcription factor in multiple types of cancer, c-Myc can directly transform cells by transactivating various downstream genes. Given that there is no effective way to directly inhibit c-Myc, c-Myc targeting strategies based on its regulatory mechanism hold great potential for cancer therapy. In this study, we found that WSB1, a direct target gene of c-Myc, can positively regulate c-Myc expression, which forms a feedforward circuit promoting cancer development. Luciferase-based promoter activity assays and RNA sequencing results confirmed that WSB1 promoted c-Myc expression through the {beta}-catenin pathway. Mechanistically, WSB1 affected {beta}-catenin destruction complex-PPP2CA assembly and E3 ubiquitin ligase adaptor {beta}-TRCP recruitment, which inhibited the ubiquitination of {beta}-catenin and subsequently transactivated c-Myc. Of interest, the promoting effect of WSB1 on c-Myc was independent of its E3 ligase activity. Moreover, co-expression of WSB1 and c-Myc strongly enhanced the initiation and progression of tumours both in vitro and in vivo. Thus, our findings revealed a novel mechanism involved in tumorigenesis in which the WSB1/c-Myc feedforward circuit played an essential role, highlighting a potential c-Myc intervention strategy in cancer treatment.

Aldo-keto oxidoreductase (AKR) inhibitors could reverse several cancer cells resistance to Cis-platin, but their role in resistance remains unclear. Our RNA-seq results showed de novo NAD biosynthesis-related genes, and NAD(P)H-dependent oxidoreductases were significantly upregulated in Cis-platin-resistant HepG2 hepatic cancer cells (HepG2-RC cells) compared with HepG2 cells. Knockdown of AKR1Cs could increase Cis-platin sensitivity in HepG2-RC cells about two-fold. Interestingly, the AKR1C inhibitor meclofenamic acid could increase Cis-platin sensitivity of HepG2-RC cells about eight-fold, indicating that knockdown of AKR1Cs only partially reversed the resistance. Meanwhile, the amount of total NAD and the ratio of NADH/NAD+ were increased in HepG2-RC cells compared with HepG2 cells. The increased NADH could be explained as a directly operating antioxidant to scavenge radicals induced by Cis-platin. We report here that NADH, which is produced by NAD(P)H-dependent oxidoreductases, plays a key role in the AKR-associated Cis-platin resistance of HepG2 hepatic cancer cells.

Testicular homeostasis requires the balanced interplay between specific molecules in Sertoli cells, Leydig cells, germ cells. Loss of this coordination can lead to the disruption of spermatogenesis, even male infertility. By operating the upregulation and downregulation of Sirt3 in our male subfertility rats model and two testicular cells models, we indicated that Sirt3 overexpression and activator ameliorated cholesterol metabolism via P450scc deacetylation in Leydig cells, and cytoskeleton assembly via PDLIM1 with SOD2 deacetylation in Sertoli cells and elongating spermatids. In terms of the upstream regulator of Sirt3, the phosphorylation of NF-{kappa}B p65Ser536 stimulated the nuclear translocation of NF-{kappa}B subunits (p50, p65, RelB), which bound to TFBS1 and TFBS2 synchronously in the promoter of Sirt3, repressing Sirt3 transcription. This study demonstrates that NF-{kappa}B-repressed SIRT3 acts directly on cholesterol metabolism of Leydig cells and cytoskeleton assembly of Sertoli cells via P450scc/SOD2 deacetylation to regulate sperm differentiation, influencing spermatogenesis, even male fertility. Research organism: Rat, mouse

Ferroptosis is a form of regulated cell death closely associated with glutathione depletion and accumulation of reactive lipid peroxides. In the present study, we seek to determine whether 2-hydroxyestrone (2-OH-E1) and 2-hydroxyestradiol (2-OH-E2), two major metabolites of endogenous estrone and 17{beta}-estradiol formed in liver by cytochrome P450 enzymes, can strongly protect against erastin- and RSL3-induced ferroptosis in hepatoma cells (H-4-II-E and HuH-7) in vitro and acetaminophen-induced mouse liver injury in vivo. We find that 2-OH-E1 and 2-OH-E2 can protect, in a dose-dependent manner, H-4-II-E hepatoma cells against erastin/RSL3-induced ferroptosis. Similar protective effect of 2-OH-E1 and 2-OH-E2 against RSL3-induced ferroptosis is also observed in HuH-7 hepatoma cells. These two estrogen metabolites strongly reduce the levels of erastin- and/or RSL3-induced accumulation of cellular NO, ROS and lipid-ROS. Mechanistically, 2-OH-E1 and 2-OH-E2 protect cells against chemically-induced ferroptosis mainly by binding to cellular protein disulfide isomerase (PDI), and then inhibit its catalytic activity and reduce PDI-catalyzed formation of iNOS dimer, thereby abrogating cellular NO, ROS and lipid-ROS accumulation. Animal studies show that 2-OH-E1 and 2-OH-E2 can also exert a strong protection against acetaminophen-induced liver injury in mice. Interestingly, while estrone and 17{beta}-estradiol display a very weak protective effect in cultured hepatoma cells, they exert a similarly-strong protective effect as 2-OH-E1 and 2-OH-E2 in vivo, suggesting that the metabolic conversion of estrone and 17{beta}-estradiol to 2-OH-E1 and 2-OH-E2 contributes importantly to their hepatoprotective effect. The results of this study reveal that 2-OH-E1 and 2-OH-E2 are important endogenous factors for protection against chemically-induced liver injury in vivo.

A low-glucose microenvironment can induce metabolic abnormalities in tumour cells, including hepatocellular carcinoma (HCC) cells, and enhance cancer cell stemness. Isthmin-1 (ISM1) is a recently identified adipokine that promotes glucose uptake and enhances cellular metabolism. While the activity of the ISM1 protein is regulated by glycosylases, its transcriptional and posttranscriptional regulation remain poorly understood. A novel alternatively spliced variant of ISM1 (ISM1-AS) was recently identified. Unlike canonical ISM1, ISM1-AS lacks an AMOP domain, a key structural element required for ISM1 function, suggesting the loss of its metabolic regulatory activity. In this study, we found that ISM1 expression was significantly reduced in HCC tissues and correlated with poor prognosis. Functional assays revealed that ISM1 overexpression markedly suppressed HCC cell proliferation and invasion, whereas ISM1-AS overexpression had the opposite effect. Importantly, ISM1 co-overexpression attenuated the oncogenic effects of ISM1-AS. Knockdown of the antisense transcript lncRNA-ISM1 reduced ISM1-AS expression while increasing ISM1 expression, thereby suppressing HCC proliferation and migration. Mechanistically, lncRNA-ISM1 regulated ISM1 alternative splicing by interacting with RBM10, thereby altering the balance between ISM1-AS and ISM1. This shift activated the Akt-S6 signalling pathway, promoting glycolysis and HCC progression. In vivo experiments further confirmed that the lncRNA-ISM1/ISM1-AS/ISM1 axis drives tumour growth via Akt-S6 activation. Our findings demonstrate that lncRNA-ISM1 promotes HCC progression through the RBM10-mediated alternative splicing of ISM1 and activation of the Akt-S6 signalling pathway, highlighting its potential as a therapeutic target for HCC.

BACKGROUNDTreating cerebral ischemia/reperfusion injury (CIRI) is challenging, with iron metabolism imbalances and oxidative stress worsening the condition. While low-intensity repetitive transcranial magnetic stimulation (LI-rTMS) shows potential in brain protection, its effects on iron processing and antioxidant use are unclear. This study explored LI-rTMSs role in regulating iron homeostasis and antioxidant defense for potential therapeutic use in CIRI. METHODSA rat model of CIRI was established using a filament insertion technique, followed by neurological and infarct volume assessments. In PC12 cells, oxidative damage was induced with H2O2 or ferric ammonium citrate (FAC), then treated with LI-rTMS or deferoxamine (DFP). Parameters measured included oxidative stress markers, iron metabolism markers, and mitochondrial integrity. Gene knockdown and overexpression experiments explored mechanisms involving LI-rTMS and ACSL4. RESULTSLI-rTMS improved neurological deficits by boosting GPX4 activity and inhibiting the ACSL4-LPCAT3-LOX axis, reducing lipid peroxidation. It restored iron balance by lowering TFR and DMT1, decreasing ferritin and hepcidin, and increasing FPN for better iron efflux. LI-rTMS also prevented the Fenton reaction, reduced ROS production, and maintained mitochondrial structure and transmembrane potential. CONCLUSIONSLI-rTMS offers neuroprotection by regulating iron homeostasis through dual pathways: boosting export (via FPN) and reducing uptake/storage (via TFR/DMT1/FE). It also provides ACSL4-dependent antioxidant benefits, suggesting its potential to prevent ferroptosis in CIRI.

Intervertebral disc degeneration (IDD) increases the risk of low back pain (LBP). Oxidative stress may induce cellular damage and contribute to various diseases including IDD. Endoplasmic reticulum autophagy (ER-phagy) is a specific type of autophagy, its role in oxidative stress induced damage as well as in IDD is unknown. This study explores the role of ER-phagy in oxidative damage in intervertebral disc nucleus pulposus cells (NPCs), as well as the Nrf2/FAM134B axis in ER-phagy regulation and IDD therapy. We found ER-phagy was decreased in NPCs during oxidative stress; while FAM134B may promote ER-phagy and alleviate oxidative stress induced ER-stress and apoptosis. In addition, the nuclear transcription factor Nrf2 may promote the expression of FAM134B as well as ER-phagy, and suppress ER-stress and apoptosis in NPCs. Furthermore, overexpression of FAM134B and Nrf2 could effectively attenuate the progression of IDD in rats in vivo. These results suggest Nrf2/FAM134B mediated ER-phagy may combat oxidative damage in cells; meanwhile, ER-phagy as well as Nrf2 could be potential therapeutic targets for IDD. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=114 SRC="FIGDIR/small/469451v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@188b390org.highwire.dtl.DTLVardef@1c4e4f6org.highwire.dtl.DTLVardef@193fe77org.highwire.dtl.DTLVardef@12770e2_HPS_FORMAT_FIGEXP M_FIG C_FIG

Acute lung injury is a topic of great interest in critical care medicine due to its high mortality rates. The lungs are the immediate target organ for formaldehyde inhalation damage. Lung damage and fibrosis are the most important outcomes of severe and acute lung disease and pose a serious threat to human health. Melatonin (MT), a natural bioactive compound with anti-inflammatory and antioxidant properties, However, it is not clear whether MT can prevent FA-induced acute lung injury (ALI). Therefore, in this study, we aimed to evaluate the protective effects of MT and the potential mechanisms against FA-induced ALI. An environmental exposure bin was used to inhale 3 mg{middle dot}m3 FA-induced ALI, which was given intraperitoneally with different doses of MT (5/10/20 mg/kg) after successful modeling. In addition, rats were treated with Nrf2 inhibitor (ML385) to validate the signaling pathway. Lung function was measured, histopathological/morphological changes in lung tissue were assessed, and inflammatory expression and oxidation levels in lung tissue were detected. We observed that MT greatly alleviated the lung dysfunction, pathological lung injury, pulmonary edema and inflammatory response after successful modeling of FA. In additional, MT played a role in modulating the Nrf2/HO-1 signaling pathway, which effectively inhibit oxidative stress caused by FA-induced lung tissue injure. Moreover, we found that activation of the NF-{kappa}B pathway is associated with inflammation caused by this injury. Overall, our data suggest that MT inhibits the expression of oxidative stress and inflammation in lung tissue through the institutional or Nrf2/HO-1 pathway, alleviating FA-induced ALI.

NFE2L1 (also called Nrf1) acts a core regulator of redox signaling and metabolism homeostasis, and thus its dysfunction results in multiple systemic metabolic diseases. However, the molecular mechanism(s) by which NFE2L1 regulates glycose and lipid metabolism is still elusive. Here, we found that the loss of NFE2L1 in human HepG2 cells led to a lethal phenotype upon glucose deprivation. The uptake of glucose was also affected by NFE2L1 deficiency. Further experiments unveiled that although the glycosylation of NFE2L1 was monitored through the glycolysis pathway, it enabled to sense the energy state and directly interacted with AMPK. These indicate that NFE2L1 can serve as a dual sensor and regulator of glucose homeostasis. In-depth sights into transcriptome, metabolome and seahorse data further unraveled that glucose metabolism was reprogrammed by disruption of NFE2L1, so as to aggravate the Warburg effect in NFE2L1-silenced hepatoma cells, along with the mitochondrial damage observed under the electron microscope. Collectively, these demonstrate that disfunction of NFE2L1 triggers the uncontrollable signaling by AMPK towards glucose metabolism reprogramming in the liver cancer development.

The treatment of uterine fibroids and the development of new drugs depend on adeeper understanding of the developmental mechanisms of uterine fibroids. Here, the role of ESR1 and miR-17 on the uterine fibroids cell proliferation and apoptosis and their relationship were investigated in USMCs. Our results showed that ESR1 increased the proliferation of USMCs and inhibited their apoptosis. In addition, ESR1 could directly bind the promoter regionof TP53 and inhibit its expression. MiR-17 increased the apoptosis of USMCs and inhibited their proliferation via decreasing the level of ESR1 by targeting its 3UTR. Our research provides a new understanding of the development of uterine fibroids and provides a theoretical basis for the treatment of uterine fibroids.

Antitumor transcription activator NFE2L1, with the functions to regulate redox homeostasis, protein turnover, and material metabolism, plays an important role in embryonic development and specialization of tissue and organ functions. Deficiency of NFE2L1 gene in different regions yields distinct phenotypes, suggesting that NFE2L1 may have a transcription factor-independent function. Here we originally discovered the non-transcription factor activity of NFE2L1 by constructing a truncated protein-NFE2L1{Delta}C without 152 aa at the C-terminus which lost the transcription factor activity. The regulation of NFE2L1 on redox homeostasis, proteasome function, and immune response mainly depends on its transcription activator function in nucleus, while the regulation on metabolism, ribosome function, and canceration is germanely to its non-transcription factor activity in cytoplasm. Surprisingly, the results indicated the tumor suppressive effect of NFE2L1 by repression of Wnt/{beta}-catenin signaling in a non-transcription factor manner, indicating the potential value of NFE2L1 as a therapeutic target in clinical cancer treatment independent of its transcription factor activity. Our observations reveal the non-transcription factor activity of NFE2L1 for the first time, and lay foundation for the basic and applied research of NFE2L1.