1
|
Methylcyclopentadienyl Manganese Tricarbonyl Alter Behavior and Cause Ultrastructural Changes in the Substantia Nigra of Rats: Comparison with Inorganic Manganese Chloride. Neurochem Res 2022; 47:2198-2210. [PMID: 35513760 DOI: 10.1007/s11064-022-03606-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 03/23/2022] [Accepted: 04/10/2022] [Indexed: 10/18/2022]
Abstract
The antiknock additive methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic manganese(Mn) compound. Mn neurotoxicity caused by occupational Mn exposure (mostly inorganic MnCl2) is associated with motor and cognitive disturbances, referred to as Manganism. However, the impact of environmentally relevant Mn exposure on MMT-induced Manganism is poorly understood. In this investigation, we studied the effects of MMT on motor function and brain structure, and compared its effects with those of inorganic MnCl2. After adaptive feeding for 7 days, male and female Sprague-Dawley (SD) rats in the MMT-treated groups and positive control group were treated for 8 weeks with MMT (1, 2 and 4 mg/kg/i.g.) or MnCl2·4H2O (200 mg/kg/i.g.). Mn content in blood, liver, spleen and distinct brain regions was determined by inductively coupled plasma-mass spectrometer (ICP-MS). We found that MMT and MnCl2 exposure led to slower body-weight-gain in female rats, impaired motor and balance function and spatial learning and memory both in male and female rats. HE staining showed that MMT and MnCl2 led to altered structure of the substantia nigra pars compacta (SNpc), and Nissl staining corroborated MMT's propensity to damage the SNpc both in male and female rat. In addition, Immunostaining of the SNpc showed decreased TH-positive neurons in MMT- and MnCl2-treated rats, concomitant with Iba1 activation in microglia. Moreover, no statistically significant difference was noted between the rats in the H-MMT and MnCl2 groups. In summary, these findings suggest that MMT and MnCl2 exposure cause ultrastructural changes in the SNpc neurons culminating in altered motor behavior and cognition, suggesting that altered SNpc structure and function may underline the motor and cognitive deficits inherent to Manganism, and accounting for MMT and MnCl2's manifestations of atypical parkinsonism.
Collapse
|
2
|
Tan Y, Cheng H, Su C, Chen P, Yang X. PI3K/Akt Signaling Pathway Ameliorates Oxidative Stress-Induced Apoptosis upon Manganese Exposure in PC12 Cells. Biol Trace Elem Res 2022; 200:749-760. [PMID: 33772736 DOI: 10.1007/s12011-021-02687-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 03/21/2021] [Indexed: 12/16/2022]
Abstract
Manganese (Mn)-induced neurotoxicity has aroused public concerns for many years, but its precise mechanism is still poorly understood. Herein, we report the impacts of the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway in mediating neurological effects induced by manganese sulfate (MnSO4) exposure in PC12 cells. In this study, cells were treated with MnSO4 for 24 h in the absence or presence of LY294002 (a special inhibitor of PI3K). We investigated cell viability and apoptosis signals, as well as levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and malondialdehyde (MDA). The mRNA levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and Caspase-3 were also quantified through real-time quantitative PCR (RT-qPCR); protein levels of serine/threonine protein kinase (Akt) and forkhead box O3A (Foxo3a) were determined by western blot. Increasing of MnSO4 doses led to decreased SOD, GSH-Px, and CAT activities, while the level of MDA was upregulated. Moreover, cell apoptosis was significantly increased, as the mRNA of Bcl-2 and Caspase-3 was significantly decreased, while Bax mRNA was increased. Phosphorylated Akt (p-Akt) and Foxo3a (p-Foxo3a) were upregulated in a dose-dependent manner. In addition, LY294002 pretreatment reduced the activity of SOD, GSH-Px, and CAT but elevated MDA levels. Meanwhile, LY294002 pretreatment also increased cell apoptosis given the upregulated Bax and Caspase-3 mRNAs and decreased Bcl-2 mRNA. In summary, the PI3K/Akt signaling pathway can be activated by MnSO4 exposure and mediate MnSO4-induced neurotoxicity.
Collapse
Affiliation(s)
- Yanli Tan
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China
- Guangxi Collaborative Innovation Center for Genomic and Personalized Medicine, Nanning, Guangxi, China
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, No. 22 Shuangyong Road, Nanning, 530021, Guangxi, China
| | - Hong Cheng
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China
- Guangxi Collaborative Innovation Center for Genomic and Personalized Medicine, Nanning, Guangxi, China
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, No. 22 Shuangyong Road, Nanning, 530021, Guangxi, China
| | - Cheng Su
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China
- Guangxi Collaborative Innovation Center for Genomic and Personalized Medicine, Nanning, Guangxi, China
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, No. 22 Shuangyong Road, Nanning, 530021, Guangxi, China
| | - Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Xiaobo Yang
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China.
- Guangxi Collaborative Innovation Center for Genomic and Personalized Medicine, Nanning, Guangxi, China.
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, No. 22 Shuangyong Road, Nanning, 530021, Guangxi, China.
- Department of Public Health, School of Medicine, Guangxi University of Science and Technology, Liuzhou, Guangxi, China.
| |
Collapse
|
3
|
Moyano P, García JM, García J, Anadon MJ, Naval MV, Frejo MT, Sola E, Pelayo A, Pino JD. Manganese increases Aβ and Tau protein levels through proteasome 20S and heat shock proteins 90 and 70 alteration, leading to SN56 cholinergic cell death following single and repeated treatment. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 203:110975. [PMID: 32678756 DOI: 10.1016/j.ecoenv.2020.110975] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/10/2020] [Accepted: 06/29/2020] [Indexed: 06/11/2023]
Abstract
Manganese (Mn) produces cholinergic neuronal loss in basal forebrain (BF) region that was related to cognitive dysfunction induced after single and repeated Mn treatment. All processes that generate cholinergic neuronal loss in BF remain to be understood. Mn exposure may produce the reduction of BF cholinergic neurons by increasing amyloid beta (Aβ) and phosphorylated Tau (pTau) protein levels, altering heat shock proteins' (HSPs) expression, disrupting proteasome P20S activity and generating oxidative stress. These mechanisms, described to be altered by Mn in regions different than BF, could lead to the memory and learning process alteration produced after Mn exposure. The research performed shows that single and repeated Mn treatment of SN56 cholinergic neurons from BF induces P20S inhibition, increases Aβ and pTau protein levels, produces HSP90 and HSP70 proteins expression alteration, and oxidative stress generation, being the last two effects mediated by NRF2 pathway alteration. The increment of Aβ and pTau protein levels was mediated by HSPs and proteasome dysfunction. All these mechanisms mediated the cell decline observed after Mn treatment. Our results are relevant because they may assist to reveal the processes leading to the neurotoxicity and cognitive alterations observed after Mn exposure.
Collapse
Affiliation(s)
- Paula Moyano
- Department of Pharmacology and Toxicology, Veterinary School, Complutense University of Madrid, 28040, Madrid, Spain
| | - José Manuel García
- Department of Pharmacology and Toxicology, Veterinary School, Complutense University of Madrid, 28040, Madrid, Spain
| | - Jimena García
- Department of Pharmacolgy, Health Sciences School, Alfonso X University, 28691, Madrid, Spain
| | - María José Anadon
- Department of Legal Medicine, Psychiatry and Pathology, Medicine School, Complutense University of Madrid, 28041, Madrid, Spain
| | - María Victoria Naval
- Department of Pharmacology, Pharmacognosy and Botany, Pharmacy School, Complutense University of Madrid, 28040, Madrid, Spain
| | - María Teresa Frejo
- Department of Pharmacology and Toxicology, Veterinary School, Complutense University of Madrid, 28040, Madrid, Spain
| | - Emma Sola
- Department of Legal Medicine, Psychiatry and Pathology, Medicine School, Complutense University of Madrid, 28041, Madrid, Spain
| | - Adela Pelayo
- Department of Legal Medicine, Psychiatry and Pathology, Medicine School, Complutense University of Madrid, 28041, Madrid, Spain
| | - Javier Del Pino
- Department of Pharmacology and Toxicology, Veterinary School, Complutense University of Madrid, 28040, Madrid, Spain.
| |
Collapse
|
4
|
Tian FJ, Li WX, Lyu Y, Zhang P, Mu JB, Pei QL, Zheng JP. Heat-shock protein 70 (HSP70) polymorphisms affect the risk of coke-oven emission-induced neurobehavioral damage. Neurotoxicology 2019; 76:174-182. [PMID: 31730894 DOI: 10.1016/j.neuro.2019.11.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/29/2019] [Accepted: 11/07/2019] [Indexed: 02/08/2023]
Abstract
OBJECTIVES Epidemiology studies indicated that coke-oven workers with long-term exposure to polycyclic aromatic hydrocarbons (PAHs) often have some neurobehavioral abnormalities especially impairment for cognitive function, while the underlying mechanisms are not fully understood. Numerous studies have indicated the antioxidant and anti-apoptosis roles of heat shock protein 70 (Hsp70). The genetic polymorphisms in HSP70 genes are associated with multiple diseases including neurotoxicity. However, it is unclear whether HSP70 polymorphisms are related to the neurotoxicity of PAH. We, therefore, investigate the possible association between HSP70 polymorphisms and neurobehavioral abnormalities. METHODS 188 coke-oven workers and 137 control workers were recruited in this study. Emotional and cognitive function was assessed using the WHO/NCTB. HSP70 polymorphisms (HSP70-1 G190C, HSP70-2 G1267 A and HSP70-hom T2437C) were checked by PCR-RFLP. RESULTS The results indicated that HSP70-1 CC genotypes in coke-oven workers were associated with poor neurobehavioral performance such as the attention /response speed and visual perception/memory, while the HSP70-2 AA genotypes were associated with lower short-term auditory memory. CONCLUSIONS HSP70-1 CC and HSP70-2 AA genotypes in coke-oven workers may increase the risk for neurobehavioral damage, especially attention, learning and memory.
Collapse
Affiliation(s)
- Feng-Jie Tian
- Department of Health Toxicology, School of Public Health in Shanxi Medical University, Taiyuan 030001, China
| | - Wei-Xing Li
- Taiyuan Health Bureau, Taiyuan 030001, China
| | - Yi Lyu
- Department of Health Toxicology, School of Public Health in Shanxi Medical University, Taiyuan 030001, China
| | - Ping Zhang
- Department of Health Toxicology, School of Public Health in Shanxi Medical University, Taiyuan 030001, China
| | - Jian-Bing Mu
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, MD 20852, USA
| | - Qiu-Ling Pei
- Department of Health Toxicology, School of Public Health in Shanxi Medical University, Taiyuan 030001, China
| | - Jin-Ping Zheng
- Department of Health Toxicology, School of Public Health in Shanxi Medical University, Taiyuan 030001, China; Changzhi Medical College, Changzhi 046000, China.
| |
Collapse
|
5
|
Huntington's disease associated resistance to Mn neurotoxicity is neurodevelopmental stage and neuronal lineage dependent. Neurotoxicology 2019; 75:148-157. [PMID: 31545971 DOI: 10.1016/j.neuro.2019.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 08/06/2019] [Accepted: 09/09/2019] [Indexed: 12/15/2022]
Abstract
Manganese (Mn) is essential for neuronal health but neurotoxic in excess. Mn levels vary across brain regions and neurodevelopment. While Mn requirements during infanthood and childhood are significantly higher than in adulthood, the relative vulnerability to excess extracellular Mn across human neuronal developmental time and between distinct neural lineages is unknown. Neurological disease is associated with changes in brain Mn homeostasis and pathology associated with Mn neurotoxicity is not uniform across brain regions. For example, mutations associated with Huntington's disease (HD) decrease Mn bioavailability and increase resistance to Mn cytotoxicity in human and mouse striatal neuronal progenitors. Here, we sought to compare the differences in Mn cytotoxicity between control and HD human-induced pluripotent stem cells (hiPSCs)-derived neuroprogenitor cells (NPCs) and maturing neurons. We hypothesized that there would be differences in Mn sensitivity between lineages and developmental stages. However, we found that the different NPC lineage specific media substantially influenced Mn cytotoxicity in the hiPSC derived human NPCs and did so consistently even in a non-human cell line. This limited the ability to determine which human neuronal sub-types were more sensitive to Mn. Nonetheless, we compared within neuronal subtypes and developmental stage the sensitivity to Mn cytotoxicity between control and HD patient derived neuronal lineages. Consistent with studies in other striatal model systems the HD genotype was associated with resistance to Mn cytotoxicity in human striatal NPCs. In addition, we report an HD genotype-dependent resistance to Mn cytotoxicity in cortical NPCs and hiPSCs. Unexpectedly, the HD genotype conferred increased sensitivity to Mn in early post-mitotic midbrain neurons but had no effect on Mn sensitivity in midbrain NPCs or post-mitotic cortical neurons. Overall, our data suggest that sensitivity to Mn cytotoxicity is influenced by HD genotype in a human neuronal lineage type and stage of development dependent manner.
Collapse
|
6
|
Yang Y, Ma S, Wei F, Liang G, Yang X, Huang Y, Wang J, Zou Y. Pivotal role of cAMP-PKA-CREB signaling pathway in manganese-induced neurotoxicity in PC12 cells. ENVIRONMENTAL TOXICOLOGY 2019; 34:1052-1062. [PMID: 31161640 DOI: 10.1002/tox.22776] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/05/2019] [Accepted: 05/09/2019] [Indexed: 06/09/2023]
Abstract
Manganese (Mn) plays a critical role in individual growth and development, yet excessive exposure can result in neurotoxicity, especially cognitive impairment. Neuronal apoptosis is considered as one of the mechanisms of Mn-induced neurotoxicity. Recent evidence suggests that cAMP-PKA-CREB signaling regulates apoptosis and is associated with cognitive function. However, whether this pathway participates in Mn-induced neurotoxicity is not completely understood. To fill this gap, in vitro cultures of PC12 cells were exposed to 0, 400, 500, and 600 μmol/L Mn for 24 hours, respectively. Another group of cells were pretreated with 10.0 μmol/L rolipram (a phosphodiesterase-4 [PDE4] inhibitor) for 1 hour followed by 500 μmol/L Mn exposure for 24 hours. Flow cytometry, immunofluorescence staining, enzyme-linked immunosorbent assay, and Western blot analysis were used to detect the apoptosis rate, protein levels of PDE4, cAMP signaling, and apoptosis-associated proteins, respectively. We found that Mn exposure significantly inhibited cAMP signaling and protein expression of Bcl-2, while increasing apoptosis rate, protein levels of PDE4, Bax, activated caspase-3, and activated caspase-8 in PC12 cells. Pretreatment of rolipram ameliorated Mn-induced deficits in cAMP signaling and apoptosis. These findings demonstrate that cAMP-PKA-CREB signaling pathway-induced apoptosis is involved in Mn-induced neurotoxicity.
Collapse
Affiliation(s)
- Yiping Yang
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Shuyan Ma
- Department of Toxicology, Shaanxi Provincial Center for Disease Control and Prevention, Xi'an, China
| | - Fu Wei
- Center for Reproductive Medicine and Genetics, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Guiqiang Liang
- Department of Preventive Medicine, School of Public Health and Management, Guangxi University of Chinese Medicine, Nanning, China
| | - Xiaobo Yang
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, China
| | - Yuman Huang
- Guangxi Center for Disease Prevention and Control, Nanning, China
| | - Jian Wang
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, China
| | - Yunfeng Zou
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| |
Collapse
|
7
|
Cheng H, Xia B, Su C, Chen K, Chen X, Chen P, Zou Y, Yang X. PI3K/Akt signaling pathway and Hsp70 activate in hippocampus of rats with chronic manganese sulfate exposure. J Trace Elem Med Biol 2018; 50:332-338. [PMID: 30262300 DOI: 10.1016/j.jtemb.2018.07.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/15/2018] [Accepted: 07/23/2018] [Indexed: 12/11/2022]
Abstract
Manganese (Mn) has come to the forefront of environmental concerns due to its neurotoxicity. However, the toxic effect of Mn is not fully understood. The purpose of this study is to investigate the impacts of chronic manganese sulfate (MnSO4) exposure in regulating the phosphatidylinositol 3 kinase/protein kinase B (PI3K/Akt) signaling pathway in rats. In this study, rats were treated with 0, 5.0, 10.0, and 20.0 mg/kg MnSO4•H2O five days a week for 24 weeks via intraperitoneal injection. At the end of the exposure period, the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), malondialdehyde (MDA), and heat shock protein (Hsp70) in rats' plasma were quantified; the mRNA expression levels of caspase-3, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), serine-threonine protein kinase (Akt-1), and forkhead box O3a (FoxO3a) were measured through real-time quantitative PCR (RT-PCR); and the levels of protein Hsp70 and Akt were assessed by western blot. With an increasing dose of MnSO4, the organ coefficients of all tested organs were significantly increased, except the testis. Compared with the control group, the activities of plasma SOD, GSH-Px, and CAT in MnSO4-exposed groups were significantly decreased, while the concentrations of plasma MDA and Hsp70 were significantly increased. Moreover, the hippocampal mRNA levels of Bcl-2, caspase-3, Akt-1, and FoxO3a in MnSO4-exposed groups were downregulated, but the level of Bax was upregulated. Meanwhile, the level of phosphorylation of Akt (p-Akt) and Hsp70 proteins tends to be upregulated by increasing MnSO4 exposure (P < 0.05). The plasma Hsp70 level was negatively associated with SOD, CAT, and GSH-Px activities (P < 0.05), and positively associated with blood MDA concentration and hippocampal Hsp70 levels (P < 0.05). Chronic MnSO4 exposure can result in apoptosis of central nerve cells, activate the PI3K/Akt signaling pathway in rats' hippocampus, and upregulate Hsp70 transcription and translation.
Collapse
Affiliation(s)
- Hong Cheng
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Bing Xia
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Cheng Su
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Kangcheng Chen
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Xiang Chen
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, United States
| | - Yunfeng Zou
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China; Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaobo Yang
- Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China; Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, Guangxi, China; Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.
| |
Collapse
|
8
|
Kamemura N. Methylcyclopentadienyl manganese tricarbonyl increases cell vulnerability to oxidative stress on rat thymocytes. Drug Chem Toxicol 2018; 42:140-146. [PMID: 29359594 DOI: 10.1080/01480545.2018.1424180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Methylcyclopentadienyl manganese tricarbonyl (MMT) is used as a gasoline antiknock additive. However, the toxic effect of MMT is currently not well understood. In this study, we investigated the toxic effect of MMT on rat thymocytes using a flow cytometer and fluorescent probes. MMT at 100-300 µM significantly increased the population of cells exhibiting propidium fluorescence, i.e., the population of dead cells. The intensity of BES-So-AM fluorescence significantly increased when using 100 µM MMT. In addition, the intensity of oxonol fluorescence in rat thymocytes increased with the treatment with MMT in a concentration-dependent manner (10-100 µM). The toxic effect of MMT was inhibited by quercetin, antioxidant flavonoid. Moreover, co-treatment with 30-100 µM MMT and 100 µM H2O2 increased the cell lethality further. These results indicate that MMT increases cell vulnerability to oxidative stress on rat thymocytes. This study provides insight into the toxic effect of MMT on the immune system.
Collapse
Affiliation(s)
- Norio Kamemura
- a Division of Bioscience and Bioindustry , Tokushima University , Tokushima , Japan
| |
Collapse
|
9
|
Pfalzer AC, Bowman AB. Relationships Between Essential Manganese Biology and Manganese Toxicity in Neurological Disease. Curr Environ Health Rep 2017; 4:223-228. [PMID: 28417441 PMCID: PMC5515274 DOI: 10.1007/s40572-017-0136-1] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
PURPOSE OF REVIEW Manganese (Mn) is critical for neurodevelopment but also has been implicated in the pathophysiology of several neurological diseases. We discuss how Mn requirements intersect with Mn biology and toxicity, and how these requirements may be altered in neurological disease. Furthermore, we discuss the emerging evidence that the level of Mn associated with optimal overall efficiency for Mn biology does not necessarily coincide with optimal cognitive outcomes. RECENT FINDINGS Studies have linked Mn exposures with urea cycle metabolism and autophagy, with evidence that exposures typically neurotoxic may be able to correct deficiencies in these processes at least short term. The line between Mn-dependent biology and toxicity is thus blurred. Further, new work suggests that Mn exposures correlating to optimal cognitive scores in children are associated with cognitive decline in adults. This review explores relationships between Mn-dependent neurobiology and Mn-dependent neurotoxicity. We propose the hypothesis that Mn levels/exposures that are toxic to some biological processes are beneficial for other biological processes and influenced by developmental stage and disease state.
Collapse
Affiliation(s)
- Anna C Pfalzer
- Departments of Pediatrics, Vanderbilt University Medical Center (VUMC), Nashville, TN, USA
- Department of Neurology, Vanderbilt University Medical Center (VUMC), Nashville, TN, USA
| | - Aaron B Bowman
- Departments of Pediatrics, Vanderbilt University Medical Center (VUMC), Nashville, TN, USA.
- Department of Neurology, Vanderbilt University Medical Center (VUMC), Nashville, TN, USA.
- Department of Biochemistry, Vanderbilt Brain Institute, Kennedy Center for Research and Human Development, Vanderbilt University, Nashville, TN, USA.
| |
Collapse
|
10
|
Søvik E, LaMora A, Seehra G, Barron AB, Duncan JG, Ben-Shahar Y. Drosophila divalent metal ion transporter Malvolio is required in dopaminergic neurons for feeding decisions. GENES BRAIN AND BEHAVIOR 2017; 16:506-514. [PMID: 28220999 DOI: 10.1111/gbb.12375] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 02/16/2017] [Accepted: 02/16/2017] [Indexed: 01/06/2023]
Abstract
Members of the natural resistance-associated macrophage protein (NRAMP) family are evolutionarily conserved metal ion transporters that play an essential role in regulating intracellular divalent cation homeostasis in both prokaryotes and eukaryotes. Malvolio (Mvl), the sole NRAMP family member in insects, plays a role in food choice behaviors in Drosophila and other species. However, the specific physiological and cellular processes that require the action of Mvl for appropriate feeding decisions remain elusive. Here, we show that normal food choice requires Mvl function specifically in the dopaminergic system, and can be rescued by supplementing food with manganese. Collectively, our data indicate that the action of the Mvl transporter affects food choice behavior via the regulation of dopaminergic innervation of the mushroom bodies, a principle brain region associated with decision-making in insects. Our studies suggest that the homeostatic regulation of the intraneuronal levels of divalent cations plays an important role in the development and function of the dopaminergic system and associated behaviors.
Collapse
Affiliation(s)
- E Søvik
- Department of Biology, Washington University, St. Louis, MO, USA.,Department of Science and Mathematics, Volda University College, Volda, Norway
| | - A LaMora
- Department of Biology, Washington University, St. Louis, MO, USA
| | - G Seehra
- Department of Biology, Washington University, St. Louis, MO, USA
| | - A B Barron
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - J G Duncan
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Y Ben-Shahar
- Department of Biology, Washington University, St. Louis, MO, USA
| |
Collapse
|
11
|
"Manganese-induced neurotoxicity: a review of its behavioral consequences and neuroprotective strategies". BMC Pharmacol Toxicol 2016; 17:57. [PMID: 27814772 PMCID: PMC5097420 DOI: 10.1186/s40360-016-0099-0] [Citation(s) in RCA: 198] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 10/19/2016] [Indexed: 01/20/2023] Open
Abstract
Manganese (Mn) is an essential heavy metal. However, Mn’s nutritional aspects are paralleled by its role as a neurotoxicant upon excessive exposure. In this review, we covered recent advances in identifying mechanisms of Mn uptake and its molecular actions in the brain as well as promising neuroprotective strategies. The authors focused on reporting findings regarding Mn transport mechanisms, Mn effects on cholinergic system, behavioral alterations induced by Mn exposure and studies of neuroprotective strategies against Mn intoxication. We report that exposure to Mn may arise from environmental sources, occupational settings, food, total parenteral nutrition (TPN), methcathinone drug abuse or even genetic factors, such as mutation in the transporter SLC30A10. Accumulation of Mn occurs mainly in the basal ganglia and leads to a syndrome called manganism, whose symptoms of cognitive dysfunction and motor impairment resemble Parkinson’s disease (PD). Various neurotransmitter systems may be impaired due to Mn, especially dopaminergic, but also cholinergic and GABAergic. Several proteins have been identified to transport Mn, including divalent metal tranporter-1 (DMT-1), SLC30A10, transferrin and ferroportin and allow its accumulation in the central nervous system. Parallel to identification of Mn neurotoxic properties, neuroprotective strategies have been reported, and these include endogenous antioxidants (for instance, vitamin E), plant extracts (complex mixtures containing polyphenols and non-characterized components), iron chelating agents, precursors of glutathione (GSH), and synthetic compounds that can experimentally afford protection against Mn-induced neurotoxicity.
Collapse
|