Bavachin Induces Ferroptosis through the STAT3/P53/SLC7A11 Axis in Osteosarcoma Cells

Ferroptosis is a new form of regulated cell death, which is mediated by intracellular iron. Although it is reported that bavachin has antitumour effects on several tumour cells and prompts the reactive oxygen species (ROS) generation, it is unclear whether ferroptosis can be induced by bavachin in osteosarcoma (OS) cells. In this study, we found that bavachin inhibits the viability of MG63 and HOS OS cell lines along with an increase in the ferrous iron level, ROS accumulation, malondialdehyde overexpression, and glutathione depletion. Moreover, iron chelators (deferoxamine), antioxidants (Vit E), and ferroptosis inhibitors (ferrostatin-1 and liproxstatin-1) reverse bavachin-induced cell death. Bavachin also altered the mitochondrial morphology of OS cells, leading to smaller mitochondria, higher density of the mitochondrial membrane, and reduced mitochondrial cristae. Further investigation showed that bavachin upregulated the expression of transferrin receptor, divalent metal transporter-1, and P53, along with downregulating the expression of ferritin light chain, ferritin heavy chain, p-STAT3 (705), SLC7A11, and glutathione peroxidase-4 in OS cells. More importantly, STAT3 overexpression, SLC7A11 overexpression, and pretreatment with pifithrin-α (P53 inhibitor) rescued OS cell ferroptosis induced by bavachin. The results show that bavachin induces ferroptosis via the STAT3/P53/SLC7A11 axis in OS cells.

Download Full-text

Benefits of Iron Chelators in the Treatment of Parkinson’s Disease

Neurochemical Research ◽

10.1007/s11064-021-03262-9 ◽

2021 ◽

Vol 46 (5) ◽

pp. 1239-1251

Author(s):

Xiaoyan Zeng ◽

Hedi An ◽

Fei Yu ◽

Kai Wang ◽

Lanlan Zheng ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cell Death ◽

Iron Chelator ◽

Expression Level ◽

Intracellular Iron ◽

Divalent Metal Transporter ◽

Metal Transporter ◽

Regulated Cell Death

AbstractAs a novel discovered regulated cell death pattern, ferroptosis has been associated with the development of Parkinson’s disease (PD) and has attracted widespread attention. Nevertheless, the relationship between ferroptosis and PD pathogenesis is still unclear. This study aims to investigate the effect of iron overload on dopaminergic (DA) neurons and its correlation with ferroptosis. Here we use nerve growth factor (NGF) induced PC12 cells which are derived from pheochromocytoma of the rat adrenal to establish a classical PD in vitro model. We found significantly decreased cell viability in NGF-PC12 cell under ammonium ferric citrate (FAC) administration. Moreover, excessive intracellular iron ions induced the increase of (reactive oxygen species) ROS release as well as the decrease of mitochondrial membrane potential in PC12-NGF cells. In addition, we also found that overloaded iron can activate cell apoptosis and ferroptosis pathways, which led to cell death. Furthermore, MPP-induced PD cells were characterized by mitochondrial shrinkage, decreased expression of glutathione peroxidase 4 (Gpx4) and ferritin heavy chain (FTH1), and increased divalent metal transporter (DMT1) and transferrin receptor 1 (TfR1) expression level. In contrast, Lip-1 and DFO increased the expression level of GPX4 and FTH1 compared to MPP-induced PD cell. In conclusion, we indicated that overloaded intracellular iron contributes to neurons death via apoptosis and ferroptosis pathways, while DFO, an iron chelator, can inhibit ferroptosis in order to protect the neurons in vitro.

Download Full-text

Divalent Metal Transporter 1 Knock-Down Modulates IL-1β Mediated Pancreatic Beta-Cell Pro-Apoptotic Signaling Pathways through the Autophagic Machinery

International Journal of Molecular Sciences ◽

10.3390/ijms22158013 ◽

2021 ◽

Vol 22 (15) ◽

pp. 8013

Author(s):

Taewook Kang ◽

Honggang Huang ◽

Thomas Mandrup-Poulsen ◽

Martin R. Larsen

Keyword(s):

Cell Death ◽

Divalent Metal ◽

Β Cells ◽

Β Cell ◽

Divalent Metal Transporter 1 ◽

Divalent Metal Transporter ◽

Knock Down ◽

Metal Transporter ◽

Cell Functions ◽

Protective Proteins

Pro-inflammatory cytokines promote cellular iron-import through enhanced divalent metal transporter-1 (DMT1) expression in pancreatic β-cells, consequently cell death. Inhibition of β-cell iron-import by DMT1 silencing protects against apoptosis in animal models of diabetes. However, how alterations of signaling networks contribute to the protective action of DMT1 knock-down is unknown. Here, we performed phosphoproteomics using our sequential enrichment strategy of mRNA, protein, and phosphopeptides, which enabled us to explore the concurrent molecular events in the same set of wildtype and DMT1-silenced β-cells during IL-1β exposure. Our findings reveal new phosphosites in the IL-1β-induced proteins that are clearly reverted by DMT1 silencing towards their steady-state levels. We validated the levels of five novel phosphosites of the potential protective proteins using parallel reaction monitoring. We also confirmed the inactivation of autophagic flux that may be relevant for cell survival induced by DMT1 silencing during IL-1β exposure. Additionally, the potential protective proteins induced by DMT1 silencing were related to insulin secretion that may lead to improving β-cell functions upon exposure to IL-1β. This global profiling has shed light on the signal transduction pathways driving the protection against inflammation-induced cell death in β-cells after DMT1 silencing.

Download Full-text

Hyperglycemia Does Not Affect Iron Mediated Toxicity of Cultured Endothelial and Renal Tubular Epithelial Cells: Influence of L-Carnosine

Journal of Diabetes Research ◽

10.1155/2016/8710432 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Shiqi Zhang ◽

Emmanouil Ntasis ◽

Sarah Kabtni ◽

Jaap van den Born ◽

Gerjan Navis ◽

...

Keyword(s):

Epithelial Cells ◽

Umbilical Vein ◽

Receptor Protein ◽

Dependent Manner ◽

Tubular Epithelial Cells ◽

Intracellular Iron ◽

Alternative Source ◽

Divalent Metal Transporter 1 ◽

Divalent Metal Transporter ◽

Metal Transporter

Iron has been suggested to affect the clinical course of type 2 diabetes (T2DM) as accompanying increased intracellular iron accumulation may provide an alternative source for reactive oxygen species (ROS). Although carnosine has proven its therapeutic efficacy in rodent models of T2DM, little is known about its efficacy to protect cells from iron toxicity. We sought to assess if high glucose (HG) exposure makes cultured human umbilical vein endothelial cells (HUVECs) and renal proximal tubular epithelial cells (PTECs) more susceptible to metal induced toxicity and if this is ameliorated by L-carnosine. HUVECs and PTECs, cultured under normal glucose (5 mM, NG) or HG (30 mM), were challenged for 24 h with FeCl3. Cell viability was not impaired under HG conditions nor did HG increase susceptibility to FeCl3. HG did not change the expression of divalent metal transporter 1 (DMT1), ferroportin (IREG), and transferrin receptor protein 1 (TFRC). Irrespective of glucose concentrations L-carnosine prevented toxicity in a dose-dependent manner, only if it was present during the FeCl3challenge. Hence our study indicates that iron induced cytotoxicity is not enhanced under HG conditions. L-Carnosine displayed a strong protective effect, most likely by chelation of iron mediated toxicity.

Download Full-text

The Effects of the Combination of Oral Lactoferrin and Iron Injection on Iron Homestasis, Antioxidative Abilities and Cytokines Activities of Suckling Piglets

Animals ◽

10.3390/ani9070438 ◽

2019 ◽

Vol 9 (7) ◽

pp. 438 ◽

Cited By ~ 2

Author(s):

Hu ◽

Zhao ◽

Wang ◽

Zhu

Keyword(s):

Physiological Saline ◽

Iron Level ◽

Antioxidant Ability ◽

Divalent Metal Transporter 1 ◽

Divalent Metal Transporter ◽

Metal Transporter ◽

The Third ◽

Lactoferrin Receptor ◽

Nutritional Problem ◽

Suckling Piglets

Iron deficiency is considered a common nutritional problem for suckling piglets. The aim of this study was to evaluate the effects of the combination of oral lactoferrin and iron injection on iron levels, antioxidant ability and cytokine activity in suckling piglets. A total of sixty suckling piglets taken from six sows (10 piglets per litter) with a similar parity were chosen. The lactoferrin (LF) group was orally administrated with lactoferrin solution (0.5 g/kg body weight per day) for a week, the CON group was orally administrated with the same dose of physiological saline. Each piglet (all groups) was given 100 mg of iron dextran (FeDex) by intramuscular injection at the third day of age. Six piglets (n = 6) from each group were euthanized on days 8 and 21. The oral lactoferrin improved the iron level of suckling piglets by increasing the concentrations of serum hemoglobin and hepatic iron on day 8. Gene expression of lactoferrin receptor (LFR) was significantly increased in the LF group piglets on day 8, while duodenal protein expression of the divalent metal transporter 1 (DMT1) was significantly reduced in the LF group on day 8. In addition, oral lactoferrin enhanced serum T-AOC activities and duodenal SOD activities on day 21. The LF piglets had a significantly increased serum concentration of IL-10 on day 8. These results indicated that a combination of oral lactoferrin and iron injection is a more effective method of improving the iron level by up-regulating the expression of the LFR gene, enhancing the antioxidant ability and modulating the cytokine activity in the suckling piglets.

Download Full-text

Iron Imports. V. Transport of iron through the intestinal epithelium

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00489.2005 ◽

2006 ◽

Vol 290 (3) ◽

pp. G417-G422 ◽

Cited By ~ 33

Author(s):

Yuxiang Ma ◽

Mary Yeh ◽

Kwo-yih Yeh ◽

Jonathan Glass

Keyword(s):

Iron Transport ◽

Brush Border Membrane ◽

Iron Absorption ◽

Basolateral Membrane ◽

Apical Surface ◽

Intracellular Iron ◽

Divalent Metal Transporter 1 ◽

Divalent Metal Transporter ◽

Metal Transporter ◽

Apical Compartment

Iron absorption across the brush-border membrane requires divalent metal transporter 1 (DMT1), whereas ferroportin (FPN) and hephaestin are required for exit across the basolateral membrane. However, how iron passes across the enterocyte is poorly understood. Both chaperones and transcytosis have been postulated to account for intracellular iron transport. With iron feeding, DMT1 undergoes endocytosis and FPN translocates from the apical cytosol to the basolateral membrane. The fluorescent metallosensor calcein offered to the basolateral surface of enterocytes is found in endosomes in the apical compartment, and its fluorescence is quenched when iron is offered to the apical surface. These experiments are consistent with vesicular iron transport as a possible pathway for intracellular iron transport.

Download Full-text

Iron Export through the Transporter Ferroportin 1 Is Modulated by the Iron Chaperone PCBP2

Journal of Biological Chemistry ◽

10.1074/jbc.m116.721936 ◽

2016 ◽

Vol 291 (33) ◽

pp. 17303-17318 ◽

Cited By ~ 59

Author(s):

Izumi Yanatori ◽

Des R. Richardson ◽

Kiyoshi Imada ◽

Fumio Kishi

Keyword(s):

Mammalian Cells ◽

Basolateral Membrane ◽

Intracellular Iron ◽

Divalent Metal Transporter 1 ◽

Divalent Metal Transporter ◽

Metal Transporter ◽

Cellular Iron ◽

Ferroportin 1 ◽

Iron Chaperone ◽

Iron Export

Ferroportin 1 (FPN1) is an iron export protein found in mammals. FPN1 is important for the export of iron across the basolateral membrane of absorptive enterocytes and across the plasma membrane of macrophages. The expression of FPN1 is regulated by hepcidin, which binds to FPN1 and then induces its degradation. Previously, we demonstrated that divalent metal transporter 1 (DMT1) interacts with the intracellular iron chaperone protein poly(rC)-binding protein 2 (PCBP2). Subsequently, PCBP2 receives iron from DMT1 and then disengages from the transporter. In this study, we investigated the function of PCBP2 in iron export. Mammalian genomes encode four PCBPs (i.e. PCBP1–4). Here, for the first time, we demonstrated using both yeast and mammalian cells that PCBP2, but not PCBP1, PCBP3, or PCBP4, binds with FPN1. Importantly, iron-loaded, but not iron-depleted, PCBP2 interacts with FPN1. The PCBP2-binding domain of FPN1 was identified in its C-terminal cytoplasmic region. The silencing of PCBP2 expression suppressed FPN1-dependent iron export from cells. These results suggest that FPN1 exports iron received from the iron chaperone PCBP2. Therefore, it was found that PCBP2 modulates cellular iron export, which is an important physiological process.

Download Full-text

Knockdown of endosomal/lysosomal divalent metal transporter 1 by RNA interference prevents cadmium-metallothionein-1 cytotoxicity in renal proximal tubule cells

AJP Renal Physiology ◽

10.1152/ajprenal.00198.2007 ◽

2007 ◽

Vol 293 (3) ◽

pp. F705-F712 ◽

Cited By ~ 49

Author(s):

Marouan Abouhamed ◽

Natascha A. Wolff ◽

Wing-Kee Lee ◽

Craig P. Smith ◽

Frank Thévenod

Keyword(s):

Cell Death ◽

Rna Interference ◽

Divalent Metal ◽

Small Interfering Rnas ◽

Divalent Metal Transporter 1 ◽

Divalent Metal Transporter ◽

Metal Transporter ◽

Cell Death Pathways ◽

Renal Proximal Tubule Cells ◽

Renal Proximal Tubular

Chronic exposure to Cd2+ causes renal proximal tubular (PT) damage. Cd2+ reaches the PT mainly as cadmium-metallothionein 1 (CdMT-1) complexes that are filtered at the glomerulus and then internalized in part via endocytosis mediated by megalin and cubulin. Subsequently, Cd2+ is thought to be released in the cytosol to activate cell death pathways. The proton-coupled divalent metal transporter DMT1 also transports Cd2+ and is expressed exclusively in endosomes/lysosomes in rat PT cells. Using vector-based RNA interference with short-hairpin small-interfering RNAs (shRNAs) to downregulate DMT1 in the rat renal PT cell line WKPT-0293 Cl.2, we tested the hypothesis that endosomal/lysosomal DMT1 is involved in CdMT-1 nephrotoxicity. One out of 5 shRNAs tested (sh3) significantly reduced expression of DMT1 protein detected by immunoblotting and DMT1 mRNA as determined by RT-PCR by 45.1 ± 9.6 and 36.9 ± 14.4% ( n = 5–6), respectively. Similarly, sh3 reduced perinuclear DMT1 immunostaining in transfected cells. Consistent with the assumed role of DMT1 in CdMT-1 cytotoxicity, sh3, but not the empty vector or sh5, significantly attenuated cell death induced by a 24-h exposure to 14.3 μM CdMT-1 by 35.6 ± 4.2% ( n = 13). In contrast, neither fluorescently labeled metallothionein-1 (MT-1) uptake nor free Cd2+ toxicity was altered by the effective DMT1 shRNA (sh3), indicating that cellular uptake of metal-MT-1 complexes and Cd2+-induced cell death signaling are not affected by DMT1 knockdown. Thus we conclude that endosomal/lysosomal DMT1 plays a role in renal PT CdMT-1 toxicity.

Download Full-text

Crucial role for lung iron level and regulation in the pathogenesis and severity of asthma

European Respiratory Journal ◽

10.1183/13993003.01340-2019 ◽

2020 ◽

Vol 55 (4) ◽

pp. 1901340

Author(s):

Md. Khadem Ali ◽

Richard Y. Kim ◽

Alexandra C. Brown ◽

Jemma R. Mayall ◽

Rafia Karim ◽

...

Keyword(s):

Inflammatory Responses ◽

Ex Vivo ◽

Tissue Expression ◽

Forced Expiratory Volume ◽

Iron Level ◽

Divalent Metal Transporter 1 ◽

Divalent Metal Transporter ◽

Metal Transporter ◽

Asthma Patients

Accumulating evidence highlights links between iron regulation and respiratory disease. Here, we assessed the relationship between iron levels and regulatory responses in clinical and experimental asthma.We show that cell-free iron levels are reduced in the bronchoalveolar lavage (BAL) supernatant of severe or mild–moderate asthma patients and correlate with lower forced expiratory volume in 1 s (FEV1). Conversely, iron-loaded cell numbers were increased in BAL in these patients and with lower FEV1/forced vital capacity (FVC) ratio. The airway tissue expression of the iron sequestration molecules divalent metal transporter 1 (DMT1) and transferrin receptor 1 (TFR1) are increased in asthma, with TFR1 expression correlating with reduced lung function and increased Type-2 (T2) inflammatory responses in the airways. Furthermore, pulmonary iron levels are increased in a house dust mite (HDM)-induced model of experimental asthma in association with augmented Tfr1 expression in airway tissue, similar to human disease. We show that macrophages are the predominant source of increased Tfr1 and Tfr1+ macrophages have increased Il13 expression. We also show that increased iron levels induce increased pro-inflammatory cytokine and/or extracellular matrix (ECM) responses in human airway smooth muscle (ASM) cells and fibroblasts ex vivo and induce key features of asthma in vivo, including airway hyper-responsiveness (AHR) and fibrosis, and T2 inflammatory responses.Together these complementary clinical and experimental data highlight the importance of altered pulmonary iron levels and regulation in asthma, and the need for a greater focus on the role and potential therapeutic targeting of iron in the pathogenesis and severity of disease.

Download Full-text