1
|
Burak Kandilci H, Şimşek G, Zirapli T, Çelebier M. Differential role of prolyl hydroxylases on mitochondrial function of HL-1 cells in a model of iron deficiency. Mitochondrion 2022; 63:51-56. [DOI: 10.1016/j.mito.2022.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 01/06/2022] [Accepted: 01/17/2022] [Indexed: 11/17/2022]
|
2
|
Hou K, Liu J, Du J, Mi S, Ma S, Ba Y, Ji H, Li B, Hu S. Dihydroartemisinin prompts amplification of photodynamic therapy-induced reactive oxygen species to exhaust Na/H exchanger 1-mediated glioma cells invasion and migration. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2021; 219:112192. [PMID: 34000476 DOI: 10.1016/j.jphotobiol.2021.112192] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 03/29/2021] [Accepted: 04/13/2021] [Indexed: 12/12/2022]
Abstract
Photodynamic therapy (PDT) is a promising glioma therapy; however, its efficacy is compromised due to the PDT-induced reactive oxygen species (ROS) production being limited by the local hypoxic tumor microenvironment. Furthermore, Hypoxia activates sodium/hydrogen exchanger 1 (NHE1), an essential component for tumor progression and metastasis, enables glioma cells (GC) to escape PDT-mediated phototoxicity via increased H+ extrusion. However, interactions between NHE1 expression with ROS level involving response of GC remain unclear. Dihydroartemisinin (DHA), a ROS generator, has extensive anti-tumor effects. This study aimed to explore whether PDT along with DHA could amplify the total ROS levels and diminish GC invasion and migration by inhibiting NHE1 expression. Proliferation and invasion of U251 and LN229 cells were evaluated under different treatments using cell counting Kit-8 (CCK-8), transwell, and wound healing assays. ROS levels were measured using fluorescence probes and flow cytometry. NHE1 levels were detected by immunofluorescence and western blotting. Co-treatment effects and molecular events were further confirmed in a bilateral tumor-bearing nude mouse model. PDT with synergistic DHA significantly increased the total abundance of ROS to further suppress the invasion and migration of GC by reducing NHE1 levels in vitro. Using a bilateral glioma xenograft mouse model with primary and recurrent gliomas, we found that PDT markedly suppressed primary tumor growth, while PDT in synergy with DHA also suppressed recurrent tumors, and improved overall survival by regulating the ROS-NHE1 axis. No evident side effects were observed. Our results suggest that PDT with DHA can amplify the total ROS levels to weaken GC invasion and migration by suppressing NHE1 expression in vitro and in vivo, thus abolishing the resistance of GC to PDT. The synergistic therapy of PDT and DHA therefore represents a more efficient and safe strategy for comprehensive glioma treatment.
Collapse
Affiliation(s)
- Kuiyuan Hou
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Jie Liu
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Jianyang Du
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Shan Mi
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Shuai Ma
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Yixu Ba
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Hang Ji
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Bo Li
- Department of Neurosurgery, The First People's Hospital of Taizhou, Taizhou 318020, China
| | - Shaoshan Hu
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150001, China.
| |
Collapse
|
3
|
Kandilci HB, Richards MA, Fournier M, Şimşek G, Chung YJ, Lakhal-Littleton S, Swietach P. Cardiomyocyte Na +/H + Exchanger-1 Activity Is Reduced in Hypoxia. Front Cardiovasc Med 2021; 7:617038. [PMID: 33585583 PMCID: PMC7873356 DOI: 10.3389/fcvm.2020.617038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/29/2020] [Indexed: 12/30/2022] Open
Abstract
Fully-activated Na+/H+ exchanger-1 (NHE1) generates the cardiomyocyte's largest trans-membrane extrusion of H+ ions for an equimolar influx of Na+ ions. This has the desirable effect of clearing excess intracellular acidity, but comes at a large energetic premium because the exchanged Na+ ions must ultimately be extruded by the sodium pump, a process that consumes the majority of the heart's non-contractile ATP. We hypothesize that the state of NHE1 activation depends on metabolic resources, which become limiting in periods of myocardial hypoxia. To test this functionally, NHE1 activity was measured in response to in vitro and in vivo hypoxic treatments. NHE1 flux was interrogated as a function of intracellular pH by fluorescence imaging of rodent ventricular myocytes loaded with pH-sensitive dyes BCECF or cSNARF1. Anoxic superfusates promptly inhibited NHE1, tracking the time-course of mitochondrial depolarization. Mass spectrometry of NHE1 immuno-precipitated from Langendorff-perfused anoxic hearts identified Tyr-581 dephosphorylation and Tyr-561 phosphorylation. The latter residue is part of the domain that interacts with phosphatidylinositol 4,5-bisphosphate (PIP2), a membrane lipid that becomes depleted under metabolic inhibition. Tyr-561 phosphorylation is expected to electrostatically weaken this activatory interaction. To test if a period of hypoxia produces a persistent inhibition of NHE1, measurements under normoxia were performed on myocytes that had been incubated in 2% O2 for 4 h. NHE1 activity remained inhibited, but the effect was ablated in the presence of Dasatinib, an inhibitor of Abl/Src-family tyrosine kinases. Chronic tissue hypoxia in vivo, attained in a mouse model of anemic hypoxia, also resulted in persistently slower NHE1. In summary, we show that NHE1 responds to oxygen, a physiologically-relevant metabolic regulator, ostensibly to divert ATP for contraction. We describe a novel mechanism of NHE1 inhibition that may be relevant in cardiac disorders featuring altered oxygen metabolism, such as myocardial ischemia and reperfusion injury.
Collapse
Affiliation(s)
- Hilmi Burak Kandilci
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.,Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Mark A Richards
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Marjorie Fournier
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Gül Şimşek
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.,Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Yu Jin Chung
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Samira Lakhal-Littleton
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Pawel Swietach
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| |
Collapse
|