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Wang Y, Zhao M, Cui J, Lian H, Hao Z, Lou L, Jia X, Zhao W, Shen H, Xing L, Zhang X. Ochratoxin A-enhanced glycolysis induces inflammatory responses in human gastric epithelium cells through mTOR/HIF-1α signaling pathway. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 270:115868. [PMID: 38142590 DOI: 10.1016/j.ecoenv.2023.115868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 12/16/2023] [Accepted: 12/18/2023] [Indexed: 12/26/2023]
Abstract
Ochratoxin A (OTA) is a mycotoxin commonly found in several food commodities worldwide with potential nephrotoxic, hepatotoxic and carcinogenic effects. We previously showed for the first time that OTA treatment enhanced glycolysis in human gastric epithelium (GES-1) cells in vitro. Here, we found that OTA exposure activated inflammatory responses, evidenced by increasing of NF-κB signaling pathway-related protein (p-p65 and p-IκBα) expressions and elevating of inflammatory cytokine (IL-1β and IL-6) mRNA expressions in GES-1 cells. To elucidate the role of glycolysis in inflammatory effects triggered by OTA, we pretreated GES-1 cells with glycolysis inhibitor (2-deoxy-D-glucose, 2-DG) before OTA exposure. The result showed that 2-DG reduced the protein expressions of p-p65 and p-IκBα and alleviated the mRNA expressions of inflammatory cytokines in OTA-treated GES-1 cells. Furthermore, OTA activated the mTOR/HIF-1α pathway by increasing the protein expressions of p-mTOR, p-eIF4E and HIF-1α, and inhibition of mTOR with rapamycin or silencing HIF-1α with siRNA significantly attenuated OTA-enhanced glycolysis by reducing glycolysis related genes and thereby decreasing inflammatory effects of GES-1 cells. These results demonstrate that OTA activates inflammatory responses in GES-1 cells and this is controlled by mTOR/HIF-1α pathway-mediated glycolysis enhancement. Our findings provide a novel mechanistic view into OTA-induced gastric cytotoxicity.
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Affiliation(s)
- Yuan Wang
- Department of Pathology, The Second Hospital, Hebei Medical University, Shijiazhuang, China
| | - Man Zhao
- Department of Pathology, Hebei Medical University, Shijiazhuang, China
| | - Jinfeng Cui
- Department of Pathology, The Second Hospital, Hebei Medical University, Shijiazhuang, China
| | - Hongguang Lian
- Department of Pathology, The Second Hospital, Hebei Medical University, Shijiazhuang, China
| | - Zengfang Hao
- Department of Pathology, The Second Hospital, Hebei Medical University, Shijiazhuang, China
| | - Lei Lou
- Department of Pathology, The Second Hospital, Hebei Medical University, Shijiazhuang, China
| | - Xin Jia
- Department of Pathology, The Second Hospital, Hebei Medical University, Shijiazhuang, China
| | - Wei Zhao
- Department of Pathology, The Second Hospital, Hebei Medical University, Shijiazhuang, China
| | - Haitao Shen
- Department of Pathology, Hebei Medical University, Shijiazhuang, China
| | - Lingxiao Xing
- Department of Pathology, Hebei Medical University, Shijiazhuang, China
| | - Xianghong Zhang
- Department of Pathology, The Second Hospital, Hebei Medical University, Shijiazhuang, China; Department of Pathology, Hebei Medical University, Shijiazhuang, China.
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Gaur A, Nayak P, Ghosh S, Sengupta T, Sakthivadivel V. Aluminum as a Possible Cause Toward Dyslipidemia. Indian J Occup Environ Med 2023; 27:112-119. [PMID: 37600652 PMCID: PMC10434801 DOI: 10.4103/ijoem.ijoem_349_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/24/2022] [Indexed: 08/22/2023] Open
Abstract
Aluminum, the third most abundant metal present in the earth's crust, is present almost in all daily commodities we use, and exposure to it is unavoidable. The interference of aluminum with various biochemical reactions in the body leads to detrimental health effects, out of which aluminum-induced neurodegeneration is widely studied. However, the effect of aluminum in causing dyslipidemia cannot be neglected. Dyslipidemia is a global health problem, which commences to the cosmic of non-communicable diseases. The interference of aluminum with various iron-dependent enzymatic activities in the tri-carboxylic acid cycle and electron transport chain results in decreased production of mitochondrial adenosine tri-phosphate. This ultimately contributes to oxidative stress and iron-mediated lipid peroxidation. This mitochondrial dysfunction along with modulation of α-ketoglutarate and L-carnitine perturbs lipid metabolism, leading to the atypical accumulation of lipids and dyslipidemia. Respiratory chain disruption because of the accumulation of reduced nicotinamide adenine di-nucleotide as a consequence of oxidative stress and the stimulatory effect of aluminum exposure on glycolysis causes many health issues including fat accumulation, obesity, and other hepatic disorders. One major factor contributing to dyslipidemia and enhanced pro-inflammatory responses is estrogen. Aluminum, being a metalloestrogen, modulates estrogen receptors, and in this world of industrialization and urbanization, we could corner down to metals, particularly aluminum, in the development of dyslipidemia. As per PRISMA guidelines, we did a literature search in four medical databases to give a holistic view of the possible link between aluminum exposure and various biochemical events leading to dyslipidemia.
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Affiliation(s)
- Archana Gaur
- Department of Physiology, All India Institute of Medical Sciences, Bibinagar, Hyderabad, Telangana, India
| | - Prasunpriya Nayak
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Sutirtha Ghosh
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Trina Sengupta
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Varatharajan Sakthivadivel
- Department of General Medicine, All India Institute of Medical Sciences, Bibinagar, Hyderabad, Telangana, India
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Li A, Li Y, Mei Y, Zhao J, Zhou Q, Li K, Zhao M, Xu J, Ge X, Xu Q. Associations of metals and metals mixture with lipid profiles: A repeated-measures study of older adults in Beijing. CHEMOSPHERE 2023; 319:137833. [PMID: 36693480 DOI: 10.1016/j.chemosphere.2023.137833] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/25/2022] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
Metals inevitably and easily enter into human bodies and can induce a series of pathophysiological changes, such as oxidative stress damage and lipid peroxidation, which then may further induce dyslipidemia. However, the effects of metals and metals mixture on the lipid profiles are still unclear, especially in older adults. A three-visits repeated measurement of 201 older adults in Beijing was conducted from November 2016 to January 2018. Linear Mixed Effects models and Bayesian kernel machine regression models were used to estimate associations of eight blood metals and metals mixture with lipid profiles, including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), Castelli risk indexes I (CRI-1), Castelli risk indexes II (CRI-2), atherogenic coefficient (AC), and non-HDL cholesterol (NHC). Cesium (Cs) was positively associated with TG (βCs = 0.14; 95% CI: 0.02, 0.26) whereas copper (Cu) was inversely related to TG (βCu = -0.65; 95%CI: -1.14, -0.17) in adjusted models. Manganese (Mn) was mainly related to higher HDL-C (βMn = 0.14; 95% CI: 0.07, 0.21) whereas molybdenum showed opposite association. Metals mixture was marginally positive associated with HDL-C, among which Mn played a crucial role. Our findings suggest that the effects of single metal on lipid profiles may be counteracted in mixtures in the context of multiple metal exposures; however, future studies with large sample size are still needed to focus on the detrimental effects of single metals on lipid profiles as well as to identify key components.
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Affiliation(s)
- Ang Li
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Yanbing Li
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Yayuan Mei
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Jiaxin Zhao
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Quan Zhou
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Kai Li
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Meiduo Zhao
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Jing Xu
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Xiaoyu Ge
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China
| | - Qun Xu
- Department of Epidemiology and Biostatistics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, 100005, China; Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China.
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Aschner M, Skalny AV, Lu R, Santamaria A, Zhou JC, Ke T, Karganov MY, Tsatsakis A, Golokhvast KS, Bowman AB, Tinkov AA. The role of hypoxia-inducible factor 1 alpha (HIF-1α) modulation in heavy metal toxicity. Arch Toxicol 2023; 97:1299-1318. [PMID: 36933023 DOI: 10.1007/s00204-023-03483-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 03/02/2023] [Indexed: 03/19/2023]
Abstract
Hypoxia-inducible factor 1 (HIF-1) is an oxygen-sensing transcriptional regulator orchestrating a complex of adaptive cellular responses to hypoxia. Several studies have demonstrated that toxic metal exposure may also modulate HIF-1α signal transduction pathway, although the existing data are scarce. Therefore, the present review aims to summarize the existing data on the effects of toxic metals on HIF-1 signaling and the potential underlying mechanisms with a special focus on prooxidant effect of the metals. The particular effect of metals was shown to be dependent on cell type, varying from down- to up-regulation of HIF-1 pathway. Inhibition of HIF-1 signaling may contribute to impaired hypoxic tolerance and adaptation, thus promoting hypoxic damage in the cells. In contrast, its metal-induced activation may result in increased tolerance to hypoxia through increased angiogenesis, thus promoting tumor growth and contributing to carcinogenic effect of heavy metals. Up-regulation of HIF-1 signaling is mainly observed upon Cr, As, and Ni exposure, whereas Cd and Hg may both stimulate and inhibit HIF-1 pathway. The mechanisms underlying the influence of toxic metal exposure on HIF-1 signaling involve modulation of prolyl hydroxylases (PHD2) activity, as well as interference with other tightly related pathways including Nrf2, PI3K/Akt, NF-κB, and MAPK signaling. These effects are at least partially mediated by metal-induced ROS generation. Hypothetically, maintenance of adequate HIF-1 signaling upon toxic metal exposure through direct (PHD2 modulation) or indirect (antioxidant) mechanisms may provide an additional strategy for prevention of adverse effects of metal toxicity.
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Affiliation(s)
- Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Anatoly V Skalny
- IM Sechenov First Moscow State Medical University (Sechenov University), 119435, Moscow, Russia
| | - Rongzhu Lu
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Abel Santamaria
- Laboratorio de Aminoácidos Excitadores/Laboratorio de Neurofarmacología Molecular y Nanotecnología, Instituto Nacional de Neurología y Neurocirugía, 14269, Mexico City, Mexico
| | - Ji-Chang Zhou
- School of Public Health (Shenzhen), Sun Yat-Sen University, Shenzhen, 518100, China
| | - Tao Ke
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | | | - Aristides Tsatsakis
- IM Sechenov First Moscow State Medical University (Sechenov University), 119435, Moscow, Russia.,Laboratory of Toxicology, Medical School, University of Crete, Voutes, 700 13, Heraklion, Crete, Greece
| | - Kirill S Golokhvast
- Siberian Federal Scientific Centre of Agrobiotechnologies of the Russian Academy of Sciences, Krasnoobsk, Russia
| | - Aaron B Bowman
- School of Health Sciences, Purdue University, West Lafayette, USA
| | - Alexey A Tinkov
- IM Sechenov First Moscow State Medical University (Sechenov University), 119435, Moscow, Russia. .,Laboratory of Ecobiomonitoring and Quality Control, Yaroslavl State University, 150003, Yaroslavl, Russia.
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Makhdoomi S, Ariafar S, Mirzaei F, Mohammadi M. Aluminum neurotoxicity and autophagy: a mechanistic view. Neurol Res 2023; 45:216-225. [PMID: 36208459 DOI: 10.1080/01616412.2022.2132727] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2022]
Abstract
It is strongly believed that aluminum is one of the insalubrious agents because of its neurotoxicity effects and influences on amyloid β (Aβ) production and tau protein hyperphosphorylation following oxidative stress, as one of the initial events in neurotoxicity. The autophagy process plays a considerable role in neurons in preserving intracellular homeostasis and recycling organelles and proteins, especially Aβ and soluble tau. Thus, autophagy is suggested to ameliorate aluminum neurotoxicity effects, and dysfunction of this process can lead to an increase in detrimental proteins. However, the relationship between aluminum neurotoxicity and autophagy dysregulation in some dimensions remains unclear. In the present review, we want to give an overview of the autophagy roles in aluminum neurotoxicity and how dysregulation of autophagy can affect aluminum neurotoxicity.
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Affiliation(s)
- Sajjad Makhdoomi
- Department of Pharmacology & Toxicology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Saba Ariafar
- Department of Pharmacology & Toxicology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Fatemeh Mirzaei
- Department of Anatomy, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mojdeh Mohammadi
- Department of Pharmacology & Toxicology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
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Pascale RM, Calvisi DF, Simile MM, Feo CF, Feo F. The Warburg Effect 97 Years after Its Discovery. Cancers (Basel) 2020; 12:E2819. [PMID: 33008042 PMCID: PMC7599761 DOI: 10.3390/cancers12102819] [Citation(s) in RCA: 144] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 09/22/2020] [Indexed: 02/06/2023] Open
Abstract
The deregulation of the oxidative metabolism in cancer, as shown by the increased aerobic glycolysis and impaired oxidative phosphorylation (Warburg effect), is coordinated by genetic changes leading to the activation of oncogenes and the loss of oncosuppressor genes. The understanding of the metabolic deregulation of cancer cells is necessary to prevent and cure cancer. In this review, we illustrate and comment the principal metabolic and molecular variations of cancer cells, involved in their anomalous behavior, that include modifications of oxidative metabolism, the activation of oncogenes that promote glycolysis and a decrease of oxygen consumption in cancer cells, the genetic susceptibility to cancer, the molecular correlations involved in the metabolic deregulation in cancer, the defective cancer mitochondria, the relationships between the Warburg effect and tumor therapy, and recent studies that reevaluate the Warburg effect. Taken together, these observations indicate that the Warburg effect is an epiphenomenon of the transformation process essential for the development of malignancy.
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Affiliation(s)
- Rosa Maria Pascale
- Department of Medical, Surgery and Experimental Sciences, Division of Experimental Pathology and Oncology, University of Sassari, 07100 Sassari, Italy; (D.F.C.); (M.M.S.); (F.F.)
| | - Diego Francesco Calvisi
- Department of Medical, Surgery and Experimental Sciences, Division of Experimental Pathology and Oncology, University of Sassari, 07100 Sassari, Italy; (D.F.C.); (M.M.S.); (F.F.)
| | - Maria Maddalena Simile
- Department of Medical, Surgery and Experimental Sciences, Division of Experimental Pathology and Oncology, University of Sassari, 07100 Sassari, Italy; (D.F.C.); (M.M.S.); (F.F.)
| | - Claudio Francesco Feo
- Department of Clinical, Surgery and Experimental Sciences, Division of Surgery, University of Sassari, 07100 Sassari, Italy;
| | - Francesco Feo
- Department of Medical, Surgery and Experimental Sciences, Division of Experimental Pathology and Oncology, University of Sassari, 07100 Sassari, Italy; (D.F.C.); (M.M.S.); (F.F.)
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Chang J, Yang B, Zhou Y, Yin C, Liu T, Qian H, Xing G, Wang S, Li F, Zhang Y, Chen D, Aschner M, Lu R. Acute Methylmercury Exposure and the Hypoxia-Inducible Factor-1α Signaling Pathway under Normoxic Conditions in the Rat Brain and Astrocytes in Vitro. ENVIRONMENTAL HEALTH PERSPECTIVES 2019; 127:127006. [PMID: 31850806 PMCID: PMC6957278 DOI: 10.1289/ehp5139] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 11/07/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND As a ubiquitous environmental pollutant, methylmercury (MeHg) induces toxic effects in the nervous system, one of its main targets. However, the exact mechanisms of its neurotoxicity have not been fully elucidated. Hypoxia-inducible factor- 1 α (HIF- 1 α ), a transcription factor, plays a crucial role in adaptive and cytoprotective responses in cells and is involved in cell survival, proliferation, apoptosis, inflammation, angiogenesis, glucose metabolism, erythropoiesis, and other physiological activities. OBJECTIVES The aim of this study was to explore the role of HIF- 1 α in response to acute MeHg exposure in rat brain and primary cultured astrocytes to improve understanding of the mechanisms of MeHg-induced neurotoxicity and the development of effective neuroprotective strategies. METHODS Primary rat astrocytes were treated with MeHg (0 - 10 μ M ) for 0.5 h . Cell proliferation and cytotoxicity were assessed with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) release assay, respectively. Reactive oxygen species (ROS) levels were analyzed to assess the level of oxidative stress using 2',7'-dichlorofluorescin diacetate (DCFH-DA) fluorescence. HIF- 1 α , and its downstream proteins, glucose transporter 1 (GLUT-1), erythropoietin (EPO), and vascular endothelial growth factor A (VEGF-A) were analyzed by means of Western blotting. Real-time PCR was used to detect the expression of HIF- 1 α mRNA. Pretreatment with protein synthesis inhibitor (CHX), proteasome inhibitor (MG132), or proline hydroxylase inhibitor (DHB) were applied to explore the possible mechanisms of HIF- 1 α inhibition by MeHg. To investigate the role of HIF- 1 α in MeHg-induced neurotoxicity, cobalt chloride (CoC l 2 ), 2-methoxyestradiol (2-MeOE2), small interfering RNA (siRNA) transfection and adenovirus overexpression were used. Pretreatment with N-acetyl-L-cysteine (NAC) and vitamin E (Trolox) were used to investigate the putative role of oxidative stress in MeHg-induced alterations in HIF- 1 α levels. The expression of HIF- 1 α and related downstream proteins was detected in adult rat brain exposed to MeHg (0 - 10 mg / kg ) for 0.5 h in vivo. RESULTS MeHg caused lower cell proliferation and higher cytotoxicity in primary rat astrocytes in a time- and concentration-dependent manner. In comparison with the control cells, exposure to 10 μ M MeHg for 0.5 h significantly inhibited the expression of astrocytic HIF- 1 α , and the downstream genes GLUT-1, EPO, and VEGF-A (p < 0.05 ), in the absence of a significant decrease in HIF- 1 α mRNA levels. When protein synthesis was inhibited by CHX, MeHg promoted the degradation rate of HIF- 1 α . MG132 and DHB significantly blocked the MeHg-induced decrease in HIF- 1 α expression (p < 0.05 ). Overexpression of HIF- 1 α significantly attenuated the decline in MeHg-induced cell proliferation, whereas the inhibition of HIF- 1 α significantly increased the decline in cell proliferation (p < 0.05 ). NAC and Trolox, two established antioxidants, reversed the MeHg-induced decline in HIF- 1 α protein levels and the decrease in cell proliferation (p < 0.05 ). MeHg suppressed the expression of HIF- 1 α and related downstream target proteins in adult rat brain. DISCUSSION MeHg induced a significant reduction in HIF- 1 α protein by activating proline hydroxylase (PHD) and the ubiquitin proteasome system (UPS) in primary rat astrocytes. Additionally, ROS scavenging by antioxidants played a neuroprotective role via increasing HIF- 1 α expression in response to MeHg toxicity. Moreover, we established that up-regulation of HIF- 1 α might serve to mitigate the acute toxicity of MeHg in astrocytes, affording a novel therapeutic target for future exploration. https://doi.org/10.1289/EHP5139.
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Affiliation(s)
- Jie Chang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Bobo Yang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Yun Zhou
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Changsheng Yin
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Tingting Liu
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Hai Qian
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Guangwei Xing
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Suhua Wang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Fang Li
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Yubin Zhang
- Department of Occupational Health and Toxicology, School of Public Health, Fudan University, Shanghai, China
| | - Da Chen
- School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, China
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Rongzhu Lu
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
- Center for Experimental Research, Kunshan Hospital Affiliated to Jiangsu University, Kunshan, China
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Yu L, Wu J, Zhai Q, Tian F, Zhao J, Zhang H, Chen W. Metabolomic analysis reveals the mechanism of aluminum cytotoxicity in HT-29 cells. PeerJ 2019; 7:e7524. [PMID: 31523502 PMCID: PMC6716502 DOI: 10.7717/peerj.7524] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 07/21/2019] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Aluminum (Al) is toxic to animals and humans. The most common sources of human exposure to Al are food and beverages. The intestinal epithelium is the first barrier against Al-induced toxicity. In this study, HT-29, a human colon cancer cell line, was selected as an in vitro model to evaluate the Al-induced alteration in metabolomic profiles and explore the possible mechanisms of Al toxicity. METHODS MTT assay was performed to determine the half-maximal inhibitory concentration of Al ions. Liquid chromatography-mass spectrometry (LC-MS) was used for metabolomic analysis, and its results were further confirmed using quantitative reverse transcription polymerase chain reaction (RT-qPCR) of nine selected genes. RESULTS Al inhibited the growth of the HT-29 cells, and its half-maximal dose for the inhibition of cell proliferation was found to be four mM. This dose was selected for further metabolomic analysis, which revealed that 81 metabolites, such glutathione (GSH), phosphatidylcholines, phosphatidylethanolamines, and creatine, and 17 metabolic pathways, such as the tricarboxylic acid cycle, pyruvate metabolism, and GSH metabolism, were significantly altered after Al exposure. The RT-qPCR results further confirmed these findings. CONCLUSION The metabolomics and RT-qPCR results indicate that the mechanisms of Al-induced cytotoxicity in HT-29 cells include cellular apoptosis, oxidative stress, and alteration of lipid, energy, and amino acid metabolism.
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Affiliation(s)
- Leilei Yu
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Research Laboratory for Probiotics, Jiangnan University, Wuxi, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Jiangping Wu
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Qixiao Zhai
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Research Laboratory for Probiotics, Jiangnan University, Wuxi, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Fengwei Tian
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Research Laboratory for Probiotics, Jiangnan University, Wuxi, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Jianxin Zhao
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- (Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou, China
| | - Hao Zhang
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- (Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, China
| | - Wei Chen
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, China
- Beijing Innovation Centre of Food Nutrition and Human Health, Beijing Technology & Business University, Wuxi, China
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Sieg H, Ellermann AL, Maria Kunz B, Jalili P, Burel A, Hogeveen K, Böhmert L, Chevance S, Braeuning A, Gauffre F, Fessard V, Lampen A. Aluminum in liver cells - the element species matters. Nanotoxicology 2019; 13:909-922. [PMID: 30938204 DOI: 10.1080/17435390.2019.1593542] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Aluminum (Al) can be ingested from food and released from packaging and can reach key organs involved in human metabolism, including the liver via systemic distribution. Recent studies discuss the occurrence of chemically distinct Al-species and their interconversion by contact with biological fluids. These Al species can vary with regard to their intestinal uptake, systemic transport, and therefore could have species-specific effects on different organs and tissues. This work aims to assess the in vitro hepatotoxic hazard potential of three different relevant Al species: soluble AlCl3 and two nanoparticulate Al species were applied, representing for the first time an investigation of metallic nanoparticles besides to mineral bound γ-Al2O3 on hepatic cell lines. To investigate the uptake and toxicological properties of the Al species, we used two different human hepatic cell lines: HepG2 and differentiated HepaRG cells. Cellular uptake was determined by different methods including light microscopy, transmission electron microscopy, side-scatter analysis, and elemental analysis. Oxidative stress, mitochondrial dysfunction, cell death mechanisms, and DNA damage were monitored as cellular parameters. While cellular uptake into hepatic cell lines occurred predominantly in the particle form, only ionic AlCl3 caused cellular effects. Since it is known, that Al species can convert one into another, and mechanisms including 'trojan-horse'-like uptake can lead to an Al accumulation in the cells. This could result in the slow release of Al ions, for which reason further hazard cannot be excluded. Therefore, individual investigation of the different Al species is necessary to assess the toxicological potential of Al particles.
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Affiliation(s)
- Holger Sieg
- Department of Food Safety, German Federal Institute for Risk Assessment , Berlin , Germany
| | - Anna Lena Ellermann
- Department of Food Safety, German Federal Institute for Risk Assessment , Berlin , Germany
| | - Birgitta Maria Kunz
- Department of Food Safety, German Federal Institute for Risk Assessment , Berlin , Germany
| | - Pégah Jalili
- ANSES, French Agency for Food, Environmental and Occupational Health Safety, Fougères Laboratory , Fougères Cedex , France
| | | | - Kevin Hogeveen
- ANSES, French Agency for Food, Environmental and Occupational Health Safety, Fougères Laboratory , Fougères Cedex , France.,ASPIC Cellular Imaging Platform , Fougères , France
| | - Linda Böhmert
- Department of Food Safety, German Federal Institute for Risk Assessment , Berlin , Germany
| | - Soizic Chevance
- University of Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) , Rennes , France
| | - Albert Braeuning
- Department of Food Safety, German Federal Institute for Risk Assessment , Berlin , Germany
| | - Fabienne Gauffre
- University of Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) , Rennes , France
| | - Valérie Fessard
- ANSES, French Agency for Food, Environmental and Occupational Health Safety, Fougères Laboratory , Fougères Cedex , France
| | - Alfonso Lampen
- Department of Food Safety, German Federal Institute for Risk Assessment , Berlin , Germany
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10
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Alpha-ketoglutarate protects Streptomyces coelicolor from visible light-induced phototoxicity. Biochem Biophys Rep 2017; 9:22-28. [PMID: 29114580 PMCID: PMC5632709 DOI: 10.1016/j.bbrep.2016.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 10/28/2016] [Accepted: 11/03/2016] [Indexed: 01/12/2023] Open
Abstract
It has been known that some Streptomyces species, including the model strain Streptomyces coelicolor, are vulnerable to visible light. Much evidence demonstrated that the phototoxicity induced by visible light is a consequence of the formation of intracellular reactive oxygen species (ROS), which are potentially harmful to cells. In this study, we found that α-ketoglutarate (α-KG) has a protective role against the phototoxicity in S. coelicolor. It could be because that α-KG can detoxify the ROS with the concomitant formation of succinate, which mediates the cells getting into anaerobiosis to produce more NADH and maintain intracellular redox homeostasis, a situation that was demonstrated by overexpressing gdhA in S. coelicolor. This finding, therefore, connects the central metabolites with the bacterial resistance against phototoxicity effect induced by visible light. Streptomyces coelicolor is sensitive to visible light induced phototoxicity. α-ketoglutarate (α-KG) has a protective role against phototoxicity in S. coelicolor. α-KG maintains intracellular NAD/NADH redox homeostasis to resist phototoxicity.
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11
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Morris G, Puri BK, Frye RE. The putative role of environmental aluminium in the development of chronic neuropathology in adults and children. How strong is the evidence and what could be the mechanisms involved? Metab Brain Dis 2017; 32:1335-1355. [PMID: 28752219 PMCID: PMC5596046 DOI: 10.1007/s11011-017-0077-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 07/19/2017] [Indexed: 02/06/2023]
Abstract
The conceptualisation of autistic spectrum disorder and Alzheimer's disease has undergone something of a paradigm shift in recent years and rather than being viewed as single illnesses with a unitary pathogenesis and pathophysiology they are increasingly considered to be heterogeneous syndromes with a complex multifactorial aetiopathogenesis, involving a highly complex and diverse combination of genetic, epigenetic and environmental factors. One such environmental factor implicated as a potential cause in both syndromes is aluminium, as an element or as part of a salt, received, for example, in oral form or as an adjuvant. Such administration has the potential to induce pathology via several routes such as provoking dysfunction and/or activation of glial cells which play an indispensable role in the regulation of central nervous system homeostasis and neurodevelopment. Other routes include the generation of oxidative stress, depletion of reduced glutathione, direct and indirect reductions in mitochondrial performance and integrity, and increasing the production of proinflammatory cytokines in both the brain and peripherally. The mechanisms whereby environmental aluminium could contribute to the development of the highly specific pattern of neuropathology seen in Alzheimer's disease are described. Also detailed are several mechanisms whereby significant quantities of aluminium introduced via immunisation could produce chronic neuropathology in genetically susceptible children. Accordingly, it is recommended that the use of aluminium salts in immunisations should be discontinued and that adults should take steps to minimise their exposure to environmental aluminium.
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Affiliation(s)
- Gerwyn Morris
- Tir Na Nog, Bryn Road seaside 87, Llanelli, Wales, SA15 2LW, UK
| | - Basant K Puri
- Department of Medicine, Imperial College London, Hammersmith Hospital, London, England, W12 0HS, UK.
| | - Richard E Frye
- College of Medicine, Department of Pediatrics, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, AR, 72202, USA
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12
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Diverse molecular resistance mechanisms of Bacillus megaterium during metal removal present in a spent catalyst. BIOTECHNOL BIOPROC E 2017. [DOI: 10.1007/s12257-016-0019-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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13
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Xu F, Liu Y, Zhao H, Yu K, Song M, Zhu Y, Li Y. Aluminum chloride caused liver dysfunction and mitochondrial energy metabolism disorder in rat. J Inorg Biochem 2017; 174:55-62. [PMID: 28605655 DOI: 10.1016/j.jinorgbio.2017.04.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Revised: 03/07/2017] [Accepted: 04/08/2017] [Indexed: 01/21/2023]
Abstract
Aluminum (Al) is known to exert hepatotoxicity. However, the mechanisms mostly are unclear. Liver is a metabolism organ that maintains the energy level and structural stability of body, mitochondria are the main sites of energy metabolism, thus, we hypothesized that mitochondrial energy metabolism disorder contributes to liver dysfunction in aluminum chloride (AlCl3) treatment rat. To verify the hypothesis, forty male Wistar rats were randomly allocated and orally exposed to 0, 64mg/kg, 128mg/kg and 256mg/kg body weight AlCl3 in drinking water for 120days, respectively. We found that AlCl3 exposure reduced the electron transport chain complexes I-V activities and adenosine triphosphate (ATP) level, as well as disturbed mitochondrial DNA transcript, presenting as the inhibited mRNA expressions of NADH dehydrogenase 1, NADH dehydrogenase 2, cytochrome b, cytochrome c oxidase subunit 1, cytochrome c oxidase subunit 3 and ATP synthase 6, indicating that AlCl3 exposure disturbs the mitochondrial energy metabolism, and it caused an increase in liver enzymes (Aspartate aminotransferase and Alanine aminotransferase) and histopathological lesions. Additionally, we found that reactive oxygen species accumulation and decreased superoxide dismutase activity in mitochondria, and increased 8-Hydroxydeoxyguanosine levels in mitochondrial DNA, demonstrating AlCl3 exposure promotes mitochondrial oxidative stress, which may be a contributing factor to mitochondrial energy metabolism disorder and liver dysfunction. The study displayed that mitochondria are the potential target of liver damage induced by AlCl3, providing considerable direction for the prevention and clinical intervention of liver diseases.
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Affiliation(s)
- Feibo Xu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Yanfen Liu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China; Liaoning Agricultural College, Yingkou 115009, China
| | - Hansong Zhao
- Zhucheng Animal Husbandry Bureau, Zhucheng 262200, China
| | - Kaiyuan Yu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Miao Song
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Yanzhu Zhu
- Institute of Special Animal and Plant Sciences of Chinese Academy of Agricultural Sciences, Changchun 130112, China
| | - Yanfei Li
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China.
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14
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Cetin I, Nalbantcilar MT, Tosun K, Nazik A. How Trace Element Levels of Public Drinking Water Affect Body Composition in Turkey. Biol Trace Elem Res 2017; 175:263-270. [PMID: 27311580 DOI: 10.1007/s12011-016-0779-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 06/12/2016] [Indexed: 12/28/2022]
Abstract
Since waterborne minerals appear in ionic form and are readily absorbed by the gastrointestinal tract, drinking water could be a crucial source of mineral intake. However, no comprehensive research has yet determined how trace elements in drinking water relate to body composition. We aimed to assess the relationship between clinically important trace elements in public drinking water and body composition in average, overweight and obese individuals in Turkey. The study's population consisted of 423 participants: 143 overweight, 138 obese and 142 healthy control individuals, grouped according to clinical cutoff points of body mass index (BMI). We measured levels of lithium (Li), nickel (Ni), lead (Pb), silicon (Si), tin (Sn), strontium (Sr), boron (B), aluminium (Al), barium (Ba) and rubidium (Rb) in samples from wells of municipal water by using inductively coupled plasma mass spectrometry. We gauged all the participants' body composition measurements with a BC-418 body composition analyser. In all the participants, body weight values showed significant positive correlations with Ni levels in drinking water, as did BMI values with Al levels and percentage of obesity with Ni, Si and B levels. In particular, Ni levels showed significant positive correlations with the basal metabolic rate, activity calories, and total activity of participants. Giving findings showing correlations between obesity-related parameters and Al, Si, B and Ni content in drinking water, we hope that these associations will be clarified with further studies including cellular, experimental and clinical studies. Hence, medical practitioners must be aware of trace element levels in drinking water for overweight and obese patients.
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Affiliation(s)
- Ihsan Cetin
- Health School, Nutrition and Dietetics Department, Batman University, Batman, Turkey.
| | - Mahmut Tahir Nalbantcilar
- Faculty of Engineering and Architecture, Geological Engineering Department, Batman University, Batman, Turkey
| | - Kezban Tosun
- Diet Outpatient Clinic, Batman State Hospital, Batman, Turkey
| | - Aydan Nazik
- Diet Outpatient Clinic, Batman State Hospital, Batman, Turkey
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15
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Susnea I, Weiskirchen R. Trace metal imaging in diagnostic of hepatic metal disease. MASS SPECTROMETRY REVIEWS 2016; 35:666-686. [PMID: 25677057 DOI: 10.1002/mas.21454] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Revised: 11/25/2014] [Accepted: 12/02/2014] [Indexed: 06/04/2023]
Abstract
The liver is the most central organ and the largest gland of the body that influences and controls a variety of metabolic and catabolic processes. It produces inconceivable many essential proteins, is responsible for the recovery of various food components, degrades toxins, mediates the bile production, and is involved in the excretion of unwanted metabolites. Several of these anabolic or catabolic functions of the liver depend on trace elements. These are either integral part of enzymes, cofactors, or act as chemical catalysts. Therefore, a lack of trace elements can lead to organ failure or systemic illness. Conversely, excessive hepatic trace element deposition resulting from genetic disorders, intoxication, extensive dietary supply, or long-term parenteral nutrition may cause hepatic inflammation, fibrosis, cirrhosis, and even hepatocellular carcinoma. Although specific serum parameters currently allow rough assessment of metal deficit and excess, the precise quantification of hepatic metal content in liver is presently only possible by different titration or staining techniques of biopsy specimens. Recently, novel innovative metal imaging techniques were developed that are on the way to replace these traditional methods. In the present review, we summarize the function of different trace elements in liver health and disease and discuss the present knowledge on how quantitative biometal imaging techniques such as synchrotron X-ray fluorescence microscopy, secondary ion mass spectrometry, and laser ablation inductively coupled plasma mass spectrometry enrich diagnostics in the detection and quantification of hepatic metal disorders. We will further discuss sample preparation, sensitivity, spatial resolution, specificity, quantification strategies, and potential future applications of metal bioimaging in experimental research and clinical daily routine. © 2015 Wiley Periodicals, Inc. Mass Spec Rev 35:666-686, 2016.
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Affiliation(s)
- Iuliana Susnea
- Central Institute of Engineering, Electronics and Analytics (ZEA-3), Forschungszentrum Jülich, D-52425, Jülich, Germany
| | - Ralf Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry, RWTH University Hospital Aachen, D-52074, Aachen, Germany.
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16
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Auger C, Alhasawi A, Contavadoo M, Appanna VD. Dysfunctional mitochondrial bioenergetics and the pathogenesis of hepatic disorders. Front Cell Dev Biol 2015; 3:40. [PMID: 26161384 PMCID: PMC4479819 DOI: 10.3389/fcell.2015.00040] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Accepted: 06/12/2015] [Indexed: 12/18/2022] Open
Abstract
The liver is involved in a variety of critical biological functions including the homeostasis of glucose, fatty acids, amino acids, and the synthesis of proteins that are secreted in the blood. It is also at the forefront in the detoxification of noxious metabolites that would otherwise upset the functioning of the body. As such, this vital component of the mammalian system is exposed to a notable quantity of toxicants on a regular basis. It therefore comes as no surprise that there are over a hundred disparate hepatic disorders, encompassing such afflictions as fatty liver disease, hepatitis, and liver cancer. Most if not all of liver functions are dependent on energy, an ingredient that is primarily generated by the mitochondrion, the power house of all cells. This organelle is indispensable in providing adenosine triphosphate (ATP), a key effector of most biological processes. Dysfunctional mitochondria lead to a shortage in ATP, the leakage of deleterious reactive oxygen species (ROS), and the excessive storage of fats. Here we examine how incapacitated mitochondrial bioenergetics triggers the pathogenesis of various hepatic diseases. Exposure of liver cells to detrimental environmental hazards such as oxidative stress, metal toxicity, and various xenobiotics results in the inactivation of crucial mitochondrial enzymes and decreased ATP levels. The contribution of the latter to hepatic disorders and potential therapeutic cues to remedy these conditions are elaborated.
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Affiliation(s)
- Christopher Auger
- Faculty of Science and Engineering, Laurentian University Greater Sudbury, ON, Canada
| | - Azhar Alhasawi
- Faculty of Science and Engineering, Laurentian University Greater Sudbury, ON, Canada
| | - Manuraj Contavadoo
- Faculty of Science and Engineering, Laurentian University Greater Sudbury, ON, Canada
| | - Vasu D Appanna
- Faculty of Science and Engineering, Laurentian University Greater Sudbury, ON, Canada
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17
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Jennings P, Schwarz M, Landesmann B, Maggioni S, Goumenou M, Bower D, Leonard MO, Wiseman JS. SEURAT-1 liver gold reference compounds: a mechanism-based review. Arch Toxicol 2014; 88:2099-133. [DOI: 10.1007/s00204-014-1410-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 10/01/2014] [Indexed: 12/20/2022]
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18
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Castonguay Z, Auger C, Thomas SC, Chahma M, Appanna VD. Nuclear lactate dehydrogenase modulates histone modification in human hepatocytes. Biochem Biophys Res Commun 2014; 454:172-7. [PMID: 25450376 DOI: 10.1016/j.bbrc.2014.10.071] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 10/14/2014] [Indexed: 12/26/2022]
Abstract
It is becoming increasingly apparent that the nucleus harbors metabolic enzymes that affect genetic transforming events. Here, we describe a nuclear isoform of lactate dehydrogenase (nLDH) and its ability to orchestrate histone deacetylation by controlling the availability of nicotinamide adenine dinucleotide (NAD(+)), a key ingredient of the sirtuin-1 (SIRT1) deacetylase system. There was an increase in the expression of nLDH concomitant with the presence of hydrogen peroxide (H2O2) in the culture medium. Under oxidative stress, the NAD(+) generated by nLDH resulted in the enhanced deacetylation of histones compared to the control hepatocytes despite no discernable change in the levels of SIRT1. There appeared to be an intimate association between nLDH and SIRT1 as these two enzymes co-immunoprecipitated. The ability of nLDH to regulate epigenetic modifications by manipulating NAD(+) reveals an intricate link between metabolism and the processing of genetic information.
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Affiliation(s)
- Zachary Castonguay
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Christopher Auger
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Sean C Thomas
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - M'hamed Chahma
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Vasu D Appanna
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada.
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19
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Lemire J, Auger C, Mailloux R, Appanna VD. Mitochondrial lactate metabolism is involved in antioxidative defense in human astrocytoma cells. J Neurosci Res 2014; 92:464-75. [PMID: 24452607 DOI: 10.1002/jnr.23338] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Revised: 10/28/2013] [Accepted: 11/04/2013] [Indexed: 12/24/2022]
Abstract
Although lactate has traditionally been known to be an end product of anaerobic metabolism, recent studies have revealed its disparate biological functions. Oxidative energy production and cell signaling are two important roles assigned to this monocarboxylic acid. Here we demonstrate that mitochondrial lactate metabolism to pyruvate mediated by lactate dehydrogenase (LDH) in a human astrocytic cell line is involved in antioxidative defense. The pooling of this α-ketoacid helps to detoxify reactive oxygen species, with the concomitant formation of acetate. In-gel activity assays following blue native PAGE electrophoresis were utilized to demonstrate the increase in mitochondrial LDH activity coupled to the decrease in pyruvate dehydrogenase activity in the cells challenged by oxidative stress. The enhanced production of pyruvate with the concomitant formation of acetate in astrocytoma cells was monitored by high-performance liquid chromatography. The ability of pyruvate to fend off oxidative stress was visualized by fluorescence microscopy with the aid of the dye 2',7'-dichlorodihydrofluorescein diacetate. Immunoblotting helped confirm the presence of elevated levels of LDH in cells exposed to oxidative stress, and recovery experiments were performed with pyruvate to diminish the oxidative burden on the astrocytoma. The acetate, generated as a consequence of the antioxidative attribute of pyruvate, was subsequently channeled toward the production of lipids, a process facilitated by the upregulation in activity of acetyl-CoA synthetase and acetyl-CoA carboxylase, as demonstrated by in-gel activity assays. The mitochondrial lactate metabolism mediated by LDH appears to play an important role in antioxidative defence in this astrocytic system.
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Affiliation(s)
- Joseph Lemire
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
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20
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Leonard MO, Limonciel A, Jennings P. Stress Response Pathways. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2014. [DOI: 10.1007/978-1-4939-0521-8_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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21
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Lin CY, Hsiao WC, Huang CJ, Kao CF, Hsu GSW. Heme oxygenase-1 induction by the ROS–JNK pathway plays a role in aluminum-induced anemia. J Inorg Biochem 2013; 128:221-8. [DOI: 10.1016/j.jinorgbio.2013.07.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 07/16/2013] [Accepted: 07/16/2013] [Indexed: 01/16/2023]
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22
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Han S, Lemire J, Appanna VP, Auger C, Castonguay Z, Appanna VD. How aluminum, an intracellular ROS generator promotes hepatic and neurological diseases: the metabolic tale. Cell Biol Toxicol 2013; 29:75-84. [PMID: 23463459 DOI: 10.1007/s10565-013-9239-0] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Accepted: 02/04/2013] [Indexed: 01/10/2023]
Abstract
Metal pollutants are a global health risk due to their ability to contribute to a variety of diseases. Aluminum (Al), a ubiquitous environmental contaminant is implicated in anemia, osteomalacia, hepatic disorder, and neurological disorder. In this review, we outline how this intracellular generator of reactive oxygen species (ROS) triggers a metabolic shift towards lipogenesis in astrocytes and hepatocytes. This Al-evoked phenomenon is coupled to diminished mitochondrial activity, anerobiosis, and the channeling of α-ketoacids towards anti-oxidant defense. The resulting metabolic reconfiguration leads to fat accumulation and a reduction in ATP synthesis, characteristics that are common to numerous medical disorders. Hence, the ability of Al toxicity to create an oxidative environment promotes dysfunctional metabolic processes in astrocytes and hepatocytes. These molecular events triggered by Al-induced ROS production are the potential mediators of brain and liver disorders.
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Affiliation(s)
- Sungwon Han
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, P3E 2C6, Canada
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23
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Jennings P, Limonciel A, Felice L, Leonard MO. An overview of transcriptional regulation in response to toxicological insult. Arch Toxicol 2012; 87:49-72. [DOI: 10.1007/s00204-012-0919-y] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 07/30/2012] [Indexed: 12/30/2022]
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24
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Contini MDC, Millen N, González M, Mahieu S. Melatonin prevents oxidative stress in ovariectomized rats treated with aluminium. Biol Trace Elem Res 2011; 144:924-43. [PMID: 21537923 DOI: 10.1007/s12011-011-9060-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Accepted: 04/08/2011] [Indexed: 12/14/2022]
Abstract
This study is designed to determine the simultaneous effect of aluminium (Al) and melatonin (Mel) treatment in intact and ovariectomized (Ovx) female rats on oxidative stress and their inter-organ relationship in the kidney and liver. Al-treated rats received an intra-peritoneal injection of solution of aluminium lactate (0.575 mg Al/100 g of body weight, three times a week), during 12 weeks. Mel groups received intra-peritoneal injections of melatonin at a dose of 10 mg/kg/day, 5 days/week, during 12 weeks. The results of this study showed that Al treatment in female rats modifies homeostasis of glutathione and the antioxidant capacity of the rat liver and kidney. The alteration of glutathione homeostasis and oxidative status was not associated with an increased lipid peroxidation in both organs with the exception of the increase observed in the liver of Ovx rats. Al also induced modifications in the activity of some enzymes related to the glutathione cycle: GSH-Px in the liver and kidney and glutathione reductase only in the kidney. Al exposure decreased CAT activity in both the kidney and liver of intact and Ovx groups. The administration of Mel in the intact and castrated females treated with Al seems to reduce oxidative changes in the liver and kidney of intact and Ovx rats.
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Affiliation(s)
- María del Carmen Contini
- Laboratorio de Investigaciones Fisiológicas Experimentales. Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Ciudad Universitaria, Paraje El Pozo. CC 242, 3000, Santa Fe, Argentina.
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25
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Auger C, Lemire J, Cecchini D, Bignucolo A, Appanna VD. The metabolic reprogramming evoked by nitrosative stress triggers the anaerobic utilization of citrate in Pseudomonas fluorescens. PLoS One 2011; 6:e28469. [PMID: 22145048 PMCID: PMC3228765 DOI: 10.1371/journal.pone.0028469] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Accepted: 11/08/2011] [Indexed: 02/01/2023] Open
Abstract
Nitrosative stress is an ongoing challenge that most organisms have to contend with. When nitric oxide (NO) that may be generated either exogenously or endogenously encounters reactive oxygen species (ROS), it produces a set of toxic moieties referred to as reactive nitrogen species (RNS). As these RNS can severely damage essential biomolecules, numerous organisms have evolved elaborate detoxification strategies to nullify RNS. However, the contribution of cellular metabolism in fending off nitrosative stress is poorly understood. Using a variety of functional proteomic and metabolomic analyses, we have identified how the soil microbe Pseudomonas fluorescens reprogrammed its metabolic networks to survive in an environment enriched by sodium nitroprusside (SNP), a generator of nitrosative stress. To combat the RNS-induced ineffective aconitase (ACN) and tricarboxylic acid (TCA) cycle, the microbe invoked the participation of citrate lyase (CL), phosphoenolpyruvate carboxylase (PEPC) and pyruvate phosphate dikinase (PPDK) to convert citrate, the sole source of carbon into pyruvate and ATP. These enzymes were not evident in the control conditions. This metabolic shift was coupled to the concomitant increase in the activities of such classical RNS detoxifiers as nitrate reductase (NR), nitrite reductase (NIR) and S-nitrosoglutathione reductase (GSNOR). Hence, metabolism may hold the clues to the survival of organisms subjected to nitrosative stress and may provide therapeutic cues against RNS-resistant microbes.
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Affiliation(s)
- Christopher Auger
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Joseph Lemire
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Dominic Cecchini
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Adam Bignucolo
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Vasu D. Appanna
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
- * E-mail:
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26
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Lemire J, Appanna VD. Aluminum toxicity and astrocyte dysfunction: a metabolic link to neurological disorders. J Inorg Biochem 2011; 105:1513-7. [PMID: 22099161 DOI: 10.1016/j.jinorgbio.2011.07.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Revised: 06/21/2011] [Accepted: 07/08/2011] [Indexed: 12/21/2022]
Abstract
Aluminum (Al) has been implicated in a variety of neurological diseases. However, the molecular mechanisms that enable Al to be involved in these disorders have yet to be fully delineated. Using astrocytes as a model of the cerebral cellular system, we have uncovered the biochemical networks that are affected by Al toxicity. In this review, we reveal how the inhibitory influence of Al on ATP production and on mitochondrial functions help generate globular astrocytes that are fat producing machines. These biological events may be the contributing factors to Al-triggered brain disorders.
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Affiliation(s)
- Joseph Lemire
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada P3E 2C6
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Mailloux RJ, Lemire J, Appanna VD. Hepatic response to aluminum toxicity: dyslipidemia and liver diseases. Exp Cell Res 2011; 317:2231-8. [PMID: 21787768 DOI: 10.1016/j.yexcr.2011.07.009] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/08/2011] [Accepted: 07/09/2011] [Indexed: 10/17/2022]
Abstract
Aluminum (Al) is a metal toxin that has been implicated in the etiology of a number of diseases including Alzheimer's, Parkinson's, dialysis encephalopathy, and osteomalacia. Al has been shown to exert its effects by disrupting lipid membrane fluidity, perturbing iron (Fe), magnesium, and calcium homeostasis, and causing oxidative stress. However, the exact molecular targets of aluminum's toxicity have remained elusive. In the present review, we describe how the use of a systems biology approach in cultured hepatoblastoma cells (HepG2) allowed the identification of the molecular targets of Al toxicity. Mitochondrial metabolism is the main site of the toxicological action of Al. Fe-dependent and redox sensitive enzymes in the tricarboxylic acid (TCA) cycle and oxidative phosphorylation (OXPHOS) are dramatically decreased by Al exposure. In an effort to compensate for diminished mitochondrial function, Al-treated cells stabilize hypoxia inducible factor-1α (HIF-1α) to increase ATP production by glycolysis. Additionally, Al toxicity leads to an increase in intracellular lipid accumulation due to enhanced lipogenesis and a decrease in the β-oxidation of fatty acids. Central to these effects is the alteration of α-ketoglutarate (KG) homeostasis. In Al-exposed cells, KG is preferentially used to quench ROS leading to succinate accumulation and HIF-1α stabilization. Moreover, the channeling of KG to combat oxidative stress leads to a reduction of l-carnitine biosynthesis and a concomitant decrease in fatty acid oxidation. The fluidity and interaction of these metabolic modules and the implications of these findings in liver-related disorders are discussed herein.
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Affiliation(s)
- Ryan J Mailloux
- Laurentian University, Department of Chemistry and Biochemistry, Canada
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Vidau C, González-Polo RA, Niso-Santano M, Gómez-Sánchez R, Bravo-San Pedro JM, Pizarro-Estrella E, Blasco R, Brunet JL, Belzunces LP, Fuentes JM. Fipronil is a powerful uncoupler of oxidative phosphorylation that triggers apoptosis in human neuronal cell line SHSY5Y. Neurotoxicology 2011; 32:935-43. [PMID: 21621551 DOI: 10.1016/j.neuro.2011.04.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2011] [Revised: 03/04/2011] [Accepted: 04/20/2011] [Indexed: 11/28/2022]
Abstract
Fipronil is a phenylpyrazole insecticide known to elicit neurotoxicity via an interaction with ionotropic receptors, namely GABA and glutamate receptors. Recently, we showed that fipronil and other phenylpyrazole compounds trigger cell death in Caco-2 cells. In this study, we investigated the mode of action and the type of cell death induced by fipronil in SH-SY5Y human neuroblastoma cells. Flow cytometric and western blot analyses demonstrated that fipronil induces cellular events belonging to the apoptosis process, such as mitochondrial potential collapse, cytochrome c release, caspase-3 activation, nuclear condensation and phosphatidylserine externalization. In addition, fipronil induces a rapid ATP depletion with concomitant activation of anaerobic glycolysis. This cellular response is characteristic of mitochondrial injury associated with a defect of the respiration process. Therefore, we also investigated the effect of fipronil on the oxygen consumption in isolated mitochondria. Interestingly, we show for the first time that fipronil is a strong uncoupler of oxidative phosphorylation at relative low concentrations. Thus in this study, we report a new mode of action by which the insecticide fipronil could triggers apoptosis.
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Affiliation(s)
- Cyril Vidau
- INRA, Laboratoire de toxicologie environnementale, UMR 406, Abeille et environnement, 84914 Avignon Cedex 9, France
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Lemire J, Mailloux R, Darwich R, Auger C, Appanna VD. The disruption of L-carnitine metabolism by aluminum toxicity and oxidative stress promotes dyslipidemia in human astrocytic and hepatic cells. Toxicol Lett 2011; 203:219-26. [PMID: 21439360 DOI: 10.1016/j.toxlet.2011.03.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 03/11/2011] [Accepted: 03/14/2011] [Indexed: 12/19/2022]
Abstract
L-Carnitine is a critical metabolite indispensable for the metabolism of lipids as it facilitates fatty acid transport into the mitochondrion where β-oxidation occurs. Human astrocytes (CCF-STTG1 cells) and hepatocytes (HepG2 cells) exposed to aluminum (Al) and hydrogen peroxide (H₂O₂), were characterized with lower levels of L-carnitine, diminished β-oxidation, and increased lipid accumulation compared to the controls. γ-Butyrobetainealdehyde dehydrogenase (BADH) and butyrobetaine dioxygenase (BBDOX), two key enzymes mediating the biogenesis of L-carnitine, were sharply reduced during Al and H₂O₂ challenge. Exposure of the Al and H₂O₂-treated cells to α-ketoglutarate (KG), led to the recovery of L-carnitine production with the concomitant reduction in ROS levels. It appears that the channeling of KG to combat oxidative stress results in decreased L-carnitine synthesis, an event that contributes to the dyslipidemia observed during Al and H₂O₂ insults in these mammalian cells. Hence, KG may help alleviate pathological conditions induced by oxidative stress.
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Affiliation(s)
- Joseph Lemire
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E2C6, Canada
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Teng M, Dang YM, Zhang JP, Zhang Q, Fang YD, Ren J, Huang YS. Microtubular stability affects cardiomyocyte glycolysis by HIF-1alpha expression and endonuclear aggregation during early stages of hypoxia. Am J Physiol Heart Circ Physiol 2010; 298:H1919-31. [PMID: 20228255 DOI: 10.1152/ajpheart.01039.2009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypoxia-inducible factor (HIF)-1alpha is a key regulator of anaerobic energy metabolism. We asked the following question: Does the breakdown of microtubular structures influence glycolysis in hypoxic cardiomyocytes by regulating HIF-1alpha? Neonatal rat cardiomyocytes were cultured under hypoxic conditions, while microtubule-stabilizing (paclitaxel) and -depolymerizing (colchicine) agents were used to change microtubular structure. Models of high microtubule-associated protein 4 (MAP4) expression and RNA interference of microtubulin expression were established. Microtubular structural changes and intracellular HIF-1alpha protein distribution were observed with laser confocal scanning microscopy. Content of key glycolytic enzymes, viability, and energy content of cardiomyocytes were determined by colorimetry and high-performance liquid chromatography. HIF-1alpha protein content and mRNA expression were determined by Western blotting and real-time PCR, respectively. Low doses of microtubule-stabilizing agent (10 mumol/l paclitaxel) and enhanced expression of MAP4 stabilized the reticular microtubular structures in hypoxic cardiomyocytes, increased the content of key glycolytic enzymes, ameliorated energy supply and enhanced cell viability, and upregulated HIF-1alpha protein expression and endonuclear aggregation. In contrast, the microtubule-depolymerizing agent (10 mumol/l colchicine) or reduced microtubulin expression had adverse affects on the same parameters, in particular, HIF-1alpha protein content and endonuclear aggregation. We conclude that microtubular structural changes influence glycolysis in the early stages of hypoxia in cardiomyocytes by regulating HIF-1alpha content. Stabilizing microtubular structures increases endonuclear and total HIF-1alpha expression, content of key glycolytic enzymes, and energy supply. These findings provide potential therapeutic targets for ameliorating cell energy metabolism during early myocardial hypoxia.
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Affiliation(s)
- Miao Teng
- Institute of Burn Research, State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical Univ., Chongqing 400038, China
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Singh R, Lemire J, Mailloux RJ, Chénier D, Hamel R, Appanna VD. An ATP and oxalate generating variant tricarboxylic acid cycle counters aluminum toxicity in Pseudomonas fluorescens. PLoS One 2009; 4:e7344. [PMID: 19809498 PMCID: PMC2752808 DOI: 10.1371/journal.pone.0007344] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Accepted: 09/11/2009] [Indexed: 01/05/2023] Open
Abstract
Although the tricarboxylic acid (TCA) cycle is essential in almost all aerobic organisms, its precise modulation and integration in global cellular metabolism is not fully understood. Here, we report on an alternative TCA cycle uniquely aimed at generating ATP and oxalate, two metabolites critical for the survival of Pseudomonas fluorescens. The upregulation of isocitrate lyase (ICL) and acylating glyoxylate dehydrogenase (AGODH) led to the enhanced synthesis of oxalate, a dicarboxylic acid involved in the immobilization of aluminum (Al). The increased activity of succinyl-CoA synthetase (SCS) and oxalate CoA-transferase (OCT) in the Al-stressed cells afforded an effective route to ATP synthesis from oxalyl-CoA via substrate level phosphorylation. This modified TCA cycle with diminished efficacy in NADH production and decreased CO(2)-evolving capacity, orchestrates the synthesis of oxalate, NADPH, and ATP, ingredients pivotal to the survival of P. fluorescens in an Al environment. The channeling of succinyl-CoA towards ATP formation may be an important function of the TCA cycle during anaerobiosis, Fe starvation and O(2)-limited conditions.
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Affiliation(s)
- Ranji Singh
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Joseph Lemire
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Ryan J. Mailloux
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Daniel Chénier
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Robert Hamel
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Vasu D. Appanna
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
- * E-mail:
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Mahieu S, Contini MDC, González M, Millen N. Melatonin reduces oxidative damage induced by aluminium in rat kidney. Toxicol Lett 2009; 190:9-15. [PMID: 19539013 DOI: 10.1016/j.toxlet.2009.06.852] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 06/04/2009] [Accepted: 06/05/2009] [Indexed: 10/20/2022]
Abstract
We evaluated the effect of melatonin (Mel), in male Wistar rats which received aluminium (Al) lactate for 12 weeks (0.57 mg Al/100g body weight (b.w.), i.p. three times per week). Moreover rats received Mel (10 mg/kg b.w. i.p. 5 days/weeks) for 12 weeks. At the end of the treatment water and sodium balances were studied, and nephrogenic cyclic adenosine monophosphate (cAMP) was also measured. Urinary osmolality was measured after the administration of desmopressin (vasopressin agonist) to assess concentrating capacity. Oxidative stress in renal tissue and Na(+)-K(+)ATPase and gamma-glutamyl transferase (GGT) activities in whole plasma membrane were determined. Sodium and water balances were impaired by Al. We found decreased urinary concentrating ability and nephrogenic cAMP excretion. Al increased the Na(+)-K(+)ATPase activity, and serum aldosterone concentration. Mel normalized serum aldosterone level, the Na(+)-K(+)ATPase activity and potassium urinary without improving water and sodium excretion. Mel treatment did not improve the impaired urinary concentrating ability. Al reduced the GGT activity, an effect that persists in Al(+) Mel. Al exposure promoted oxidative stress with an increase in lipid peroxidation (LPO), and a decrease in glutathione (GSH) and glutathione peroxidase (GSH-Px) and catalase (CAT) activities. Mel markedly attenuated oxidative stress produced by Al. This may result from the higher efficacy of melatonin in scavenging various free radicals and also because of its ability in stimulating the antioxidant enzymes. However, it only reduced some alterations in the renal functions particularly related to the water and sodium excretion, which would be independent of the increased production of reactive oxygen substances.
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Affiliation(s)
- Stella Mahieu
- Laboratorio de Investigaciones Fisiológicas Experimentales, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Ciudad Universitaria, Paraje El Pozo. CC 242, 3000 Santa Fe, Argentina.
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Mailloux RJ, Puiseux-Dao S, Appanna VD. Alpha-ketoglutarate abrogates the nuclear localization of HIF-1alpha in aluminum-exposed hepatocytes. Biochimie 2008; 91:408-15. [PMID: 19028544 DOI: 10.1016/j.biochi.2008.10.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Accepted: 10/28/2008] [Indexed: 12/21/2022]
Abstract
Aluminum (Al), a known environmental pollutant, has been linked to numerous pathologies such as Alzheimer's disease and anaemia. In this study, we show that alpha-ketoglutarate (KG) mitigates the Al-mediated nuclear accumulation of hypoxia inducible factor-1alpha (HIF-1alpha) in cultured human hepatocytes (HepG2). The nuclear localization of HIF-1alpha appeared to be triggered by the Al-induced perturbation of prolyl hydroxylase 2 (PHD2). This enzyme was markedly diminished in the Al-challenged hepatocytes. The fate of PHD2 and HIF-1alpha was intricately linked to the mitochondrial dysfunction observed during Al stress. BN-PAGE, immunoblot, and HPLC revealed that the loss of alpha-ketoglutarate dehydrogenase (KGDH) and succinate dehydrogenase (SDH) activities were coupled to the accumulation of succinate. However, the treatment of the Al-stressed cells with KG recovered the activity and expression of KGDH, SDH, and PHD2 with a concomitant decrease in the levels of HIF-1alpha in the nucleus. Taken together, these data indicate that the homeostasis of KG plays a pivotal role in aerobic and anaerobic respiration.
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Affiliation(s)
- Ryan J Mailloux
- Department of Chemistry and Biochemistry, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6, Canada
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Verstraeten SV, Aimo L, Oteiza PI. Aluminium and lead: molecular mechanisms of brain toxicity. Arch Toxicol 2008; 82:789-802. [DOI: 10.1007/s00204-008-0345-3] [Citation(s) in RCA: 333] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2008] [Accepted: 07/15/2008] [Indexed: 10/21/2022]
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Lemire J, Mailloux R, Appanna VD. Zinc toxicity alters mitochondrial metabolism and leads to decreased ATP production in hepatocytes. J Appl Toxicol 2008; 28:175-82. [PMID: 17582580 DOI: 10.1002/jat.1263] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Although zinc (Zn) is a known environmental toxicant, its impact on the cellular energy-producing machinery is not well established. This study investigated the influence of this divalent metal on the oxidative ATP producing network in human hepatocellular carcinoma (HepG2) cells. Zn-challenged cells contained more oxidized proteins and lipids compared with control cells. Zn severely impeded mitochondrial functions by inhibiting aconitase, alpha-ketoglutarate dehydrogenase, isocitrate dehydrogenase-NAD+ dependent, succinate dehydrogenase and cytochrome C oxidase Zn-exposed cells had a disparate mitochondrial metabolism compared with the control cells and produced significantly less ATP. However, the expression of isocitrate dehydrogenase-NADP+ dependent was more prominent in cells treated with Zn. Hence, Zn-induced pathologies may be due to the inability of the mitochondria to generate energy effectively.
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Affiliation(s)
- Joseph Lemire
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
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Mailloux R, Lemire J, Appanna V. Aluminum-induced mitochondrial dysfunction leads to lipid accumulation in human hepatocytes: a link to obesity. Cell Physiol Biochem 2007; 20:627-38. [PMID: 17762189 DOI: 10.1159/000107546] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2007] [Indexed: 11/19/2022] Open
Abstract
Mitochondrial dysfunction is the cause of a variety of pathologies associated with high energy-requiring tissues like the brain and muscles. Here we show that aluminum (Al) perturbs oxidative-ATP production in human hepatocytes (HepG2 cells). This Al-induced mitochondrial dysfunction promotes enhanced lipogenesis and the accumulation of the very low density lipoprotein (VLDL). Al-stressed HepG2 cells secreted more cholesterol, lipids and proteins than control cells. The level of apolipoprotein B-100 (ApoB-100) was markedly increased in the culture medium of the cells exposed to Al. (13)C-NMR and HPLC studies revealed a metabolic profile favouring lipid production and lowered ATP synthesis in Al-treated cells. Electrophoretic and immunoblot analyses pointed to increased activities and expression of lipogenic enzymes such as glycerol 3-phosphate dehydrogenase (G3PDH), acetyl CoA carboxylase (ACC) and ATP-citrate lyase (CL) in the hepatocytes exposed to Al, and a sharp diminution of enzymes mediating oxidative phosphorylation. D-Fructose elicited the maximal secretion of VLDL in the Al-challenged cells. These results suggest that the Al-evoked metabolic shift favours the accumulation of lipids at the expense of oxidative energy production in hepatocytes.
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Affiliation(s)
- Ryan Mailloux
- Department of Chemistry and Biochemistry, Laurentian University, Ontario, Canada
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Mailloux RJ, Bériault R, Lemire J, Singh R, Chénier DR, Hamel RD, Appanna VD. The tricarboxylic acid cycle, an ancient metabolic network with a novel twist. PLoS One 2007; 2:e690. [PMID: 17668068 PMCID: PMC1930152 DOI: 10.1371/journal.pone.0000690] [Citation(s) in RCA: 231] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Accepted: 06/22/2007] [Indexed: 01/08/2023] Open
Abstract
The tricarboxylic acid (TCA) cycle is an essential metabolic network in all oxidative organisms and provides precursors for anabolic processes and reducing factors (NADH and FADH2) that drive the generation of energy. Here, we show that this metabolic network is also an integral part of the oxidative defence machinery in living organisms and α-ketoglutarate (KG) is a key participant in the detoxification of reactive oxygen species (ROS). Its utilization as an anti-oxidant can effectively diminish ROS and curtail the formation of NADH, a situation that further impedes the release of ROS via oxidative phosphorylation. Thus, the increased production of KG mediated by NADP-dependent isocitrate dehydrogenase (NADP-ICDH) and its decreased utilization via the TCA cycle confer a unique strategy to modulate the cellular redox environment. Activities of α-ketoglutarate dehydrogenase (KGDH), NAD-dependent isocitrate dehydrogenase (NAD-ICDH), and succinate dehydrogenase (SDH) were sharply diminished in the cellular systems exposed to conditions conducive to oxidative stress. These findings uncover an intricate link between TCA cycle and ROS homeostasis and may help explain the ineffective TCA cycle that characterizes various pathological conditions and ageing.
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Affiliation(s)
- Ryan J. Mailloux
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Robin Bériault
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Joseph Lemire
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Ranji Singh
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Daniel R. Chénier
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Robert D. Hamel
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Vasu D. Appanna
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
- * To whom correspondence should be addressed. E-mail:
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