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Firdous SM, Khan SA, Maity A. Oxidative stress-mediated neuroinflammation in Alzheimer's disease. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024:10.1007/s00210-024-03188-3. [PMID: 38832985 DOI: 10.1007/s00210-024-03188-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/24/2024] [Indexed: 06/06/2024]
Abstract
Reactive oxygen species (ROS) are metabolic by-products that constitute an indispensable component of physiological processes, albeit their heightened presence may proffer substantial perils to biological entities. Such a proliferation gives rise to a gradual escalation of oxidative stress within the organism, thereby compromising mitochondrial functionality and inflicting harm upon various bodily systems, with a particular predilection for the central nervous system. In its nascent stages, it is plausible that inflammation has been a facilitator in the progression of the malady. The precise role of inflammation in Alzheimer's disease (AD) remains somewhat enigmatic, although it is conceivable that activated microglia and astrocytes might be implicated in the removal of amyloid-β (Aβ) deposits. Nonetheless, prolonged microglial activation is associated with Tau phosphorylation and Aβ aggregation. Research studies have indicated that AD brains upregulate complementary molecules, inflammatory cytokines, acute phase reacting agents, and other inflammatory mediators that may cause neurodegeneration. In this review, oxidative damage products will be discussed as potential peripheral biomarkers for AD and its early stages. The disordered excretion of pro-inflammatory cytokines, chemokines, oxygen, and nitrogen-reactive species, along with the stimulation of the complement system by glial cells, has the potential to disrupt the functionality of neuronal termini. This perturbation, in turn, culminates in compromised synaptic function, a phenomenon empirically linked to the manifestation of cognitive impairments. The management of neurodegenerative conditions in the context of dementia necessitates therapeutic interventions that specifically target the excessive production of inflammatory and oxidative agents. Furthermore, we shall deliberate upon the function of microglia and oxidative injury in the etiology of AD and the ensuing neurodegenerative processes.
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Affiliation(s)
- Sayed Mohammed Firdous
- Department of Pharmacology, Calcutta Institute of Pharmaceutical Technology & AHS, Uluberia, Howrah, 711316, West Bengal, India.
| | - Sahabaj Ali Khan
- Department of Pharmacology, Calcutta Institute of Pharmaceutical Technology & AHS, Uluberia, Howrah, 711316, West Bengal, India
| | - Amritangshu Maity
- Department of Pharmacology, Calcutta Institute of Pharmaceutical Technology & AHS, Uluberia, Howrah, 711316, West Bengal, India
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Goin DE, Padula AM, Woodruff TJ, Sherris A, Charbonneau K, Morello-Frosch R. Water Fluoridation and Birth Outcomes in California. ENVIRONMENTAL HEALTH PERSPECTIVES 2024; 132:57004. [PMID: 38752991 PMCID: PMC11098007 DOI: 10.1289/ehp13732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 05/18/2024]
Abstract
BACKGROUND There is a lack of research on the relationship between water fluoridation and pregnancy outcomes. OBJECTIVES We assessed whether hypothetical interventions to reduce fluoride levels would improve birth outcomes in California. METHODS We linked California birth records from 2000 to 2018 to annual average fluoride levels by community water system. Fluoride levels were collected from consumer confidence reports using publicly available data and public record requests. We estimated the effects of a hypothetical intervention reducing water fluoride levels to 0.7 ppm (the current level recommended by the US Department of Health and Human Services) and 0.5 ppm (below the current recommendation) on birth weight, birth-weight-for-gestational age z-scores, gestational age, preterm birth, small-for-gestational age, large-for-gestational age, and macrosomia using linear regression with natural cubic splines and G-computation. Inference was calculated using a clustered bootstrap with Wald-type confidence intervals. We evaluated race/ethnicity, health insurance type, fetal sex, and arsenic levels as potential effect modifiers. RESULTS Fluoride levels ranged from 0 to 2.5 ppm , with a median of 0.51 ppm . There was a small negative association on birth weight with the hypothetical intervention to reduce fluoride levels to 0.7 ppm [- 2.2 g ; 95% confidence interval (CI): - 4.4 , 0.0] and to 0.5 ppm (- 5.8 g ; 95% CI: - 10.0 , - 1.6 ). There were small negative associations with birth-weight-for-gestational-age z-scores for both hypothetical interventions (0.7 ppm : - 0.004 ; 95% CI: - 0.007 , 0.000 and 0.5 ppm : - 0.006 ; 95% CI: - 0.013 , 0.000). We also observed small negative associations for risk of large-for-gestational age for both the hypothetical interventions to 0.7 ppm [risk difference ( RD ) = - 0.001 ; 95% CI: - 0.002 , 0.000 and 0.5 ppm (- 0.001 ; 95% CI: - 0.003 , 0.000)]. We did not observe any associations with preterm birth or with being small for gestational age for either hypothetical intervention. We did not observe any associations with risk of preterm birth or small-for-gestational age for either hypothetical intervention. CONCLUSION We estimated that a reduction in water fluoride levels would modestly decrease birth weight and birth-weight-for-gestational-age z-scores in California. https://doi.org/10.1289/EHP13732.
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Affiliation(s)
- Dana E. Goin
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Amy M. Padula
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Tracey J. Woodruff
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Allison Sherris
- Emmett Interdisciplinary Program in Environment and Resources, Stanford University, Palo Alto, California, USA
| | - Kiley Charbonneau
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Rachel Morello-Frosch
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
- School of Public Health, University of California, Berkeley, Berkeley, California, USA
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Zhang Q, Li T, Shi R, Qi R, Hao X, Ma B. Fluoride promotes the secretion of inflammatory factors in microglia through NLRP3/Caspase-1/GSDMD pathway. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:19844-19855. [PMID: 38367109 DOI: 10.1007/s11356-024-32443-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 02/08/2024] [Indexed: 02/19/2024]
Abstract
It is widespread of endemic fluorosis in China, and the exposure of excessive fluoride will cause nervous system disease and activate microglia. However, the mechanism of the damage is not clear. It is well-known that NLRP3/Caspase-1/GSDMD pathway, a classic pyroptosis pathway, is widely involved in the occurrence and development of nervous system-related diseases, infectious diseases, and atherosclerotic diseases. This research aimed to explore the molecular mechanism of sodium fluoride on inflammation and pyroptosis in BV2 microglia based on the NLRP3/Caspase-1/GSDMD signaling pathway. BV2 microglia was treated with sodium fluoride at the dose of 0.25, 1, and 2 mmol/L for 24, 48, and 72 h, respectively. Cell viability, cell morphology, lactate dehydrogenase content, and related proteins and genes were examined to investigate if sodium fluoride caused damage to BV2 microglia through the pyroptosis pathway. Dithiolam (5 μmol/L), a pyroptosis inhibitor, was added for further verification. NaF could induced BV2 cells injury in a dose-dependent fashion through disrupting the integrity of cell membranes and increasing IL-1β via upregulating NLRP3, Caspase-1, and its downstream protein GSDMD. Disulfiram could improve these changes caused by NaF. In conclusion, our results suggested that NLRP3/Caspase-1/GSDMD-mediated classical pyroptosis pathway was involved in fluoride-induced BV2 microglia damage.
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Affiliation(s)
- Qiuyi Zhang
- School of Basic Medical Sciences and Forensic Medicine, Baotou Medical College, Baotou, 014040, Inner Mongolia, China
| | - Tao Li
- School of Basic Medical Sciences and Forensic Medicine, Baotou Medical College, Baotou, 014040, Inner Mongolia, China
| | - Ruili Shi
- School of Basic Medical Sciences and Forensic Medicine, Baotou Medical College, Baotou, 014040, Inner Mongolia, China
- Institute of Neuroscience, Baotou Medical College, Baotou, 014040, Inner Mongolia, China
| | - Ruifang Qi
- School of Basic Medical Sciences and Forensic Medicine, Baotou Medical College, Baotou, 014040, Inner Mongolia, China
- Institute of Neuroscience, Baotou Medical College, Baotou, 014040, Inner Mongolia, China
| | - Xiaoqiong Hao
- School of Basic Medical Sciences and Forensic Medicine, Baotou Medical College, Baotou, 014040, Inner Mongolia, China
- Institute of Neuroscience, Baotou Medical College, Baotou, 014040, Inner Mongolia, China
| | - Baohui Ma
- School of Basic Medical Sciences and Forensic Medicine, Baotou Medical College, Baotou, 014040, Inner Mongolia, China.
- Institute of Neuroscience, Baotou Medical College, Baotou, 014040, Inner Mongolia, China.
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Ottappilakkil H, Babu S, Balasubramanian S, Manoharan S, Perumal E. Fluoride Induced Neurobehavioral Impairments in Experimental Animals: a Brief Review. Biol Trace Elem Res 2023; 201:1214-1236. [PMID: 35488996 DOI: 10.1007/s12011-022-03242-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 04/09/2022] [Indexed: 02/07/2023]
Abstract
Fluoride is one of the major toxicants in the environment and is often found in drinking water at higher concentrations. Living organisms including humans exposed to high fluoride levels are found to develop mild-to-severe detrimental pathological conditions called fluorosis. Fluoride can cross the hematoencephalic barrier and settle in various brain regions. This accumulation affects the structure and function of both the central and peripheral nervous systems. The neural ultrastructure damages are reflected in metabolic and cognitive activities. Hindrances in synaptic plasticity and signal transmission, early neuronal apoptosis, functional alterations of the intercellular signaling pathway components, improper protein synthesis, dyshomeostasis of the transcriptional and neurotrophic factors, oxidative stress, and inflammatory responses are accounted for the fluoride neurotoxicity. Fluoride causes a decline in brain functions that directly influence the overall quality of life in both humans and animals. Animal studies are widely used to explore the etiology of fluoride-induced neurotoxicity. A good number of these studies support a positive correlation between fluoride intake and toxicity phenotypes closely associated with neurotoxicity. However, the experimental dosages highly surpass the normal environmental concentrations and are difficult to compare with human exposures. The treatment procedures are highly dependent on the dosage, duration of exposure, sex, and age of specimens among other factors which make it difficult to arrive at general conclusions. Our review aims to explore fluoride-induced neuronal damage along with associated histopathological, behavioral, and cognitive effects in experimental models. Furthermore, the correlation of various molecular mechanisms upon fluoride intoxication and associated neurobehavioral deficits has been discussed. Since there is no well-established mechanism to prevent fluorosis, phytochemical-based alleviation of its characteristic indications has been proposed as a possible remedial measure.
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Affiliation(s)
| | - Srija Babu
- Bharathiar University, Coimbatore, Tamilnadu, India
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Fluoride in the Central Nervous System and Its Potential Influence on the Development and Invasiveness of Brain Tumours-A Research Hypothesis. Int J Mol Sci 2023; 24:ijms24021558. [PMID: 36675073 PMCID: PMC9866357 DOI: 10.3390/ijms24021558] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
The purpose of this review is to attempt to outline the potential role of fluoride in the pathogenesis of brain tumours, including glioblastoma (GBM). In this paper, we show for the first time that fluoride can potentially affect the generally accepted signalling pathways implicated in the formation and clinical course of GBM. Fluorine compounds easily cross the blood-brain barrier. Enhanced oxidative stress, disruption of multiple cellular pathways, and microglial activation are just a few examples of recent reports on the role of fluoride in the central nervous system (CNS). We sought to present the key mechanisms underlying the development and invasiveness of GBM, as well as evidence on the current state of knowledge about the pleiotropic, direct, or indirect involvement of fluoride in the regulation of these mechanisms in various tissues, including neural and tumour tissue. The effects of fluoride on the human body are still a matter of controversy. However, given the growing incidence of brain tumours, especially in children, and numerous reports on the effects of fluoride on the CNS, it is worth taking a closer look at these mechanisms in the context of brain tumours, including gliomas.
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Babu S, Manoharan S, Ottappilakkil H, Perumal E. Role of oxidative stress-mediated cell death and signaling pathways in experimental fluorosis. Chem Biol Interact 2022; 365:110106. [PMID: 35985521 DOI: 10.1016/j.cbi.2022.110106] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 08/06/2022] [Accepted: 08/08/2022] [Indexed: 11/03/2022]
Abstract
Free radicals and other oxidants have enticed the interest of researchers in the fields of biology and medicine, owing to their role in several pathophysiological conditions, including fluorosis (Fluoride toxicity). Radical species affect cellular biomolecules such as nucleic acids, proteins, and lipids, resulting in oxidative stress. Reactive oxygen species-mediated oxidative stress is a common denominator in fluoride toxicity. Fluorosis is a global health concern caused by excessive fluoride consumption over time. Fluoride alters the cellular redox homeostasis, and its toxicity leads to the activation of cell death mechanisms like apoptosis, autophagy, and necroptosis. Even though a surfeit of signaling pathways is involved in fluorosis, their toxicity mechanisms are not fully understood. Thus, this review aims to understand the role of reactive species in fluoride toxicity with an outlook on the effects of fluoride in vitro and in vivo models. Also, we emphasized the signal transduction pathways and the mechanism of cell death implicated in fluoride-induced oxidative stress.
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Affiliation(s)
- Srija Babu
- Molecular Toxicology Laboratory, Department of Biotechnology, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India
| | - Suryaa Manoharan
- Molecular Toxicology Laboratory, Department of Biotechnology, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India
| | - Harsheema Ottappilakkil
- Molecular Toxicology Laboratory, Department of Biotechnology, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India
| | - Ekambaram Perumal
- Molecular Toxicology Laboratory, Department of Biotechnology, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
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Anti-neuroinflammatory of Chloroform Extract of Panax ginseng Root Culture on Lipopolysaccharide-stimulated BV2 Microglia Cells. Rep Biochem Mol Biol 2022; 11:125-137. [PMID: 35765526 PMCID: PMC9208560 DOI: 10.52547/rbmb.11.1.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 11/28/2021] [Indexed: 01/11/2023]
Abstract
Background It is believed that activation of microglia in the central nervous system upon detection of stimulus like lipopolysaccharides provokes neuroinflammation via the production of pro-inflammatory mediators and cytokines. The cytoprotective and anti-inflammatory properties of various folk medicine has been gaining attention as a strategy to combat various disease. This study aimed to assess the anti-neuroinflammatory properties of chloroform extract of in vitro Panax ginseng root culture based on nitric oxide and cytokines production. Methods The study was initiated with the determination of maximum non-toxic dose (MNTD) of P. ginseng root culture chloroform extract using the MTT assay. The lipopolysaccharides-stimulated BV2 microglia cells were treated with MNTD and ½MNTD of the extract and its anti-neuroinflammatory properties were assessed by measuring the production of nitric oxide (NO) via Griess assay, as well as TNF-α, IL-6 and IL-10 using Quantikine ELISA. Results It was found that the MNTD and ½MNTD of the extract did not play a significant role in the production of pro-inflammatory cytokines such as NO, TNF-α and IL-6. However, the MNTD and ½MNTD of chloroform extract significantly increased the anti-inflammatory IL-10 compared to the untreated cells. Conclusion With this, the chloroform extract of P. ginseng root culture potentially exerts anti-neuroinflammatory properties.
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Glial Purinergic Signaling-Mediated Oxidative Stress (GPOS) in Neuropsychiatric Disorders. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:1075440. [PMID: 35281471 PMCID: PMC8916856 DOI: 10.1155/2022/1075440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 01/21/2022] [Accepted: 02/09/2022] [Indexed: 11/17/2022]
Abstract
Oxidative stress (OS) has been implicated in the progression of multiple neuropsychiatric disorders, including schizophrenia (SZ), major depressive disorder (MDD), bipolar disorder, and autism. However, whether glial purinergic signaling interaction with oxidative/antioxidative system displays an important role in neuropsychiatric disorders is still unclear. In this review, we firstly summarize the oxidative/antioxidative pathways shared in different glial cells and highlight the cell type-specific difference in response to OS. Then, we collect the evidence showing the regulation of purinergic signaling in OS with an emphasis on adenosine and its receptors, P2Y1 receptor in the P2Y family and P2X7receptor in the P2X family. Available data shows that the activation of P1 receptors and P2X accelerates the OS; reversely, the activation of the P2Y family (P2Y1) causes protective effect against OS. Finally, we discuss current findings demonstrating the contribution of the purinergic signaling system to neuropsychiatric disorders and point out the potential role of OS in this process to propose a “glial purinergic-oxidative stress” (“GPOS”) hypothesis for future development of therapeutic strategies against a variety of neuropsychiatric disorders.
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NaF-induced neurotoxicity via activation of the IL-1β/JNK signaling pathway. Toxicology 2022; 469:153132. [DOI: 10.1016/j.tox.2022.153132] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/11/2022] [Accepted: 02/11/2022] [Indexed: 01/23/2023]
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Hardeland R. Melatonin and Microglia. Int J Mol Sci 2021; 22:ijms22158296. [PMID: 34361062 PMCID: PMC8347578 DOI: 10.3390/ijms22158296] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 07/23/2021] [Accepted: 07/29/2021] [Indexed: 12/15/2022] Open
Abstract
Melatonin interacts in multiple ways with microglia, both directly and, via routes of crosstalk with astrocytes and neurons, indirectly. These effects of melatonin are of relevance in terms of antioxidative protection, not only concerning free-radical detoxification, but also in prevention of processes that cause, promote, or propagate oxidative stress and neurodegeneration, such as overexcitation, toxicological insults, viral and bacterial infections, and sterile inflammation of different grades. The immunological interplay in the CNS, with microglia playing a central role, is of high complexity and includes signaling toward endothelial cells and other leukocytes by cytokines, chemokines, nitric oxide, and eikosanoids. Melatonin interferes with these processes in multiple signaling routes and steps. In addition to canonical signal transduction by MT1 and MT2 melatonin receptors, secondary and tertiary signaling is of relevance and has to be considered, e.g., via the upregulation of sirtuins and the modulation of pro- and anti-inflammatory microRNAs. Many details concerning the modulation of macrophage functionality by melatonin are obviously also applicable to microglial cells. Of particular interest is the polarization toward M2 subtypes instead of M1, i.e., in favor of being anti-inflammatory at the expense of proinflammatory activities, which is well-documented in macrophages but also applies to microglia.
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Affiliation(s)
- Rüdiger Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Göttingen, 37073 Göttingen, Germany
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11
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Martínez MA, Úbeda A, Trillo MÁ. Role of NADPH oxidase in MAPK signaling activation by a 50 Hz magnetic field in human neuroblastoma cells. Electromagn Biol Med 2021; 40:103-116. [PMID: 33345643 DOI: 10.1080/15368378.2020.1851250] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 11/01/2020] [Indexed: 12/30/2022]
Abstract
Our previous studies have shown that intermittent exposure to a 50-Hz, 100-µT sine wave magnetic field (MF) promotes human NB69 cell proliferation, mediated by activation of the epidermal growth factor receptor (EGFR) and pathways MAPK-ERK1/2 and p38; being the effects on proliferation and p38 activation blocked by the chelator N-acetylcysteine. The present work investigates the MF effects on free radical (FR) production, and the potential involvement of NADPH oxidase, the main source of reactive oxygen species (ROS), in the MF-induced activation of MAPK pathways. To this end, the field effects on MAPK-ERK1/2, -p38 and -JNK activation in the presence or absence of the NADPH oxidase inhibitor, diphenyleneiodonium chloride (DPI), as well as the expression of the p67phox subunit, were analyzed. The results revealed that field exposure increases FR production and induces early, transient expression of the cytosolic component of the NADPH oxidase, p67phox. Also, the MF-induced activation of the MAPK-JNK pathway, but not that of -ERK1/2 or -p38 pathways, was prevented in the presence of the DPI, which has been shown to significantly reduce p67phox expression. These data, together with those from previous studies, identify various, FR-dependent or -independent mechanisms, involved in the MF-induced proliferative response mediated by MAPK signaling activation.
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Affiliation(s)
| | - Alejandro Úbeda
- Servicio BEM, Dept. Investigación, Hosp, Univ. Ramón Y Cajal- IRYCIS , Madrid, Spain
| | - María Ángeles Trillo
- Servicio BEM, Dept. Investigación, Hosp, Univ. Ramón Y Cajal- IRYCIS , Madrid, Spain
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Simpson DSA, Oliver PL. ROS Generation in Microglia: Understanding Oxidative Stress and Inflammation in Neurodegenerative Disease. Antioxidants (Basel) 2020; 9:E743. [PMID: 32823544 PMCID: PMC7463655 DOI: 10.3390/antiox9080743] [Citation(s) in RCA: 426] [Impact Index Per Article: 106.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/06/2020] [Accepted: 08/08/2020] [Indexed: 12/14/2022] Open
Abstract
Neurodegenerative disorders, such as Alzheimer's disease, are a global public health burden with poorly understood aetiology. Neuroinflammation and oxidative stress (OS) are undoubtedly hallmarks of neurodegeneration, contributing to disease progression. Protein aggregation and neuronal damage result in the activation of disease-associated microglia (DAM) via damage-associated molecular patterns (DAMPs). DAM facilitate persistent inflammation and reactive oxygen species (ROS) generation. However, the molecular mechanisms linking DAM activation and OS have not been well-defined; thus targeting these cells for clinical benefit has not been possible. In microglia, ROS are generated primarily by NADPH oxidase 2 (NOX2) and activation of NOX2 in DAM is associated with DAMP signalling, inflammation and amyloid plaque deposition, especially in the cerebrovasculature. Additionally, ROS originating from both NOX and the mitochondria may act as second messengers to propagate immune activation; thus intracellular ROS signalling may underlie excessive inflammation and OS. Targeting key kinases in the inflammatory response could cease inflammation and promote tissue repair. Expression of antioxidant proteins in microglia, such as NADPH dehydrogenase 1 (NQO1), is promoted by transcription factor Nrf2, which functions to control inflammation and limit OS. Lipid droplet accumulating microglia (LDAM) may also represent a double-edged sword in neurodegenerative disease by sequestering peroxidised lipids in non-pathological ageing but becoming dysregulated and pro-inflammatory in disease. We suggest that future studies should focus on targeted manipulation of NOX in the microglia to understand the molecular mechanisms driving inflammatory-related NOX activation. Finally, we discuss recent evidence that therapeutic target identification should be unbiased and founded on relevant pathophysiological assays to facilitate the discovery of translatable antioxidant and anti-inflammatory therapeutics.
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Affiliation(s)
- Dominic S. A. Simpson
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell, Oxfordshire OX11 0RD, UK;
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, UK
| | - Peter L. Oliver
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell, Oxfordshire OX11 0RD, UK;
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, UK
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García-López AL, Hernández-Castillo J, Hernández-Kelly LC, Olivares-Bañuelos TN, Ortega A. Fluoride Exposure Affects Glutamine Uptake in Müller Glia Cells. Neurotox Res 2020; 38:765-774. [PMID: 32734566 DOI: 10.1007/s12640-020-00263-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/21/2020] [Accepted: 07/27/2020] [Indexed: 02/06/2023]
Abstract
Fluoride, a pollutant present in contaminated ground water, oral care products, food, and pesticides, has deleterious effects in the structure and function of the central nervous system. Among the established neurological defects described in the exposed population, a reduced score in intelligence quotient tests in children of contaminated areas has gained attention over the past years. Maternal fluoride exposure during gestation decreases learning and memory abilities that correlate with a significant diminution of glutamate receptors expression. Since the involvement of glia cells in the maintenance and regulation of glutamatergic synapses is well-documented, in this contribution, we characterized the effect of fluoride exposure in the regulation of glia glutamine transporters. To this end, we used the Müller glia cell line, Mio-M1, and through the use of [3H]L-Glutamine uptake experiments and a Western blot approach, we demonstrate here the functional expression of system N of glutamine transporters, SNAT3 and SNAT5, in this model of human retina radial glia cells. Furthermore, these transporters interact with the glutamate transporter excitatory amino acid transporter 1, in an activity-dependent manner. Fluoride treatment reduces glutamine uptake and cell membrane [3H]glutamine surface binding, in good correlation with a decrease in SNAT3 and 5 protein levels. These results demonstrate that glia cells respond to the presence of fluoride reducing glutamine mobilization and by these means decreases glutamate turnover suggesting a disruption of glutamatergic transmission.
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Affiliation(s)
- Ana L García-López
- Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional No. 2508, Col. San Pedro Zacatenco, Apartado Postal 14-740, 07360, Ciudad de México, Mexico
| | - Jeanett Hernández-Castillo
- Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional No. 2508, Col. San Pedro Zacatenco, Apartado Postal 14-740, 07360, Ciudad de México, Mexico
| | - Luisa C Hernández-Kelly
- Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional No. 2508, Col. San Pedro Zacatenco, Apartado Postal 14-740, 07360, Ciudad de México, Mexico
| | - Tatiana N Olivares-Bañuelos
- Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Ensenada, 22860, Baja California, Mexico
| | - Arturo Ortega
- Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional No. 2508, Col. San Pedro Zacatenco, Apartado Postal 14-740, 07360, Ciudad de México, Mexico.
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Guth S, Hüser S, Roth A, Degen G, Diel P, Edlund K, Eisenbrand G, Engel KH, Epe B, Grune T, Heinz V, Henle T, Humpf HU, Jäger H, Joost HG, Kulling SE, Lampen A, Mally A, Marchan R, Marko D, Mühle E, Nitsche MA, Röhrdanz E, Stadler R, van Thriel C, Vieths S, Vogel RF, Wascher E, Watzl C, Nöthlings U, Hengstler JG. Toxicity of fluoride: critical evaluation of evidence for human developmental neurotoxicity in epidemiological studies, animal experiments and in vitro analyses. Arch Toxicol 2020; 94:1375-1415. [PMID: 32382957 PMCID: PMC7261729 DOI: 10.1007/s00204-020-02725-2] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 03/26/2020] [Indexed: 12/29/2022]
Abstract
Recently, epidemiological studies have suggested that fluoride is a human developmental neurotoxicant that reduces measures of intelligence in children, placing it into the same category as toxic metals (lead, methylmercury, arsenic) and polychlorinated biphenyls. If true, this assessment would be highly relevant considering the widespread fluoridation of drinking water and the worldwide use of fluoride in oral hygiene products such as toothpaste. To gain a deeper understanding of these assertions, we reviewed the levels of human exposure, as well as results from animal experiments, particularly focusing on developmental toxicity, and the molecular mechanisms by which fluoride can cause adverse effects. Moreover, in vitro studies investigating fluoride in neuronal cells and precursor/stem cells were analyzed, and 23 epidemiological studies published since 2012 were considered. The results show that the margin of exposure (MoE) between no observed adverse effect levels (NOAELs) in animal studies and the current adequate intake (AI) of fluoride (50 µg/kg b.w./day) in humans ranges between 50 and 210, depending on the specific animal experiment used as reference. Even for unusually high fluoride exposure levels, an MoE of at least ten was obtained. Furthermore, concentrations of fluoride in human plasma are much lower than fluoride concentrations, causing effects in cell cultures. In contrast, 21 of 23 recent epidemiological studies report an association between high fluoride exposure and reduced intelligence. The discrepancy between experimental and epidemiological evidence may be reconciled with deficiencies inherent in most of these epidemiological studies on a putative association between fluoride and intelligence, especially with respect to adequate consideration of potential confounding factors, e.g., socioeconomic status, residence, breast feeding, low birth weight, maternal intelligence, and exposure to other neurotoxic chemicals. In conclusion, based on the totality of currently available scientific evidence, the present review does not support the presumption that fluoride should be assessed as a human developmental neurotoxicant at the current exposure levels in Europe.
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Affiliation(s)
- Sabine Guth
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Stephanie Hüser
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Angelika Roth
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Gisela Degen
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Patrick Diel
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Karolina Edlund
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | | | - Karl-Heinz Engel
- Department of General Food Technology, School of Life Sciences, TU Munich, Freising, Germany
| | - Bernd Epe
- Institute of Pharmacy and Biochemistry, University of Mainz, Mainz, Germany
| | - Tilman Grune
- Department of Molecular Toxicology, German Institute of Human Nutrition (DIfE), Nuthetal, Germany
| | - Volker Heinz
- German Institute of Food Technologies (DIL), Quakenbrück, Germany
| | - Thomas Henle
- Department of Food Chemistry, TU Dresden, Dresden, Germany
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Henry Jäger
- Institute of Food Technology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Hans-Georg Joost
- Department of Experimental Diabetology, German Institute of Human Nutrition (DIfE), Nuthetal, Germany
| | - Sabine E Kulling
- Department of Safety and Quality of Fruit and Vegetables, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, Karlsruhe, Germany
| | - Alfonso Lampen
- Department of Food Safety, Bundesinstitut für Risikobewertung (BfR), Berlin, Germany
| | - Angela Mally
- Department of Toxicology, University of Würzburg, Würzburg, Germany
| | - Rosemarie Marchan
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Doris Marko
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Eva Mühle
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Michael A Nitsche
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
- Department of Neurology, University Medical Hospital Bergmannsheil, Ruhr-University, Bochum, Germany
| | - Elke Röhrdanz
- Department of Experimental Pharmacology and Toxicology, Federal Institute for Drugs and Medical Devices (BfArM), Bonn, Germany
| | - Richard Stadler
- Institute of Food Safety and Analytic Sciences, Nestlé Research Centre, Lausanne, Switzerland
| | - Christoph van Thriel
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | | | - Rudi F Vogel
- Lehrstuhl für Technische Mikrobiologie, TU Munich, Freising, Germany
| | - Edmund Wascher
- Department of Ergonomics, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Carsten Watzl
- Department of Immunology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Ute Nöthlings
- Department of Nutrition and Food Sciences, Nutritional Epidemiology, Rheinische Friedrich-Wilhelms University Bonn, Bonn, Germany.
| | - Jan G Hengstler
- Department of Toxicology, Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund, Germany.
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15
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Gao J, Su G, Liu J, Zhang J, Zhou J, Liu X, Tian Y, Zhang Z. Mechanisms of Inhibition of Excessive Microglial Activation by Melatonin. J Mol Neurosci 2020; 70:1229-1236. [PMID: 32222896 DOI: 10.1007/s12031-020-01531-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 03/12/2020] [Indexed: 12/22/2022]
Abstract
As the innate immune cells that permanently reside in the central nervous system (CNS), microglia play an increasingly important role in maintaining brain function. Normally, microglia act as resting phenotype, which can be activated by various types of stimuli and release a variety of inflammatory mediators. Melatonin is an endogenous rhythmic hormone secreted principally by the pineal gland. Increasing evidence suggests that melatonin can detoxify reactive oxygen species (ROS) and prevent microglia from over-activation. This review summarizes the mechanisms of melatonin in inhibiting excessive activation of microglia and demonstrates the feasibility of melatonin in the treatment of diseases related to microglial over-activation.
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Affiliation(s)
- Juan Gao
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, Gansu, China
| | - Gang Su
- Institute of Genetics, School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, Gansu, China
| | - Jifei Liu
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, Gansu, China
| | - Jiajia Zhang
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, Gansu, China
| | - Juanping Zhou
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, Gansu, China
| | - Xiaoyan Liu
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, Gansu, China
| | - Ye Tian
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, Gansu, China
| | - Zhenchang Zhang
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, Gansu, China.
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16
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Abstract
Although actively disputed and questioned, it has been proposed that chronic exposure to inorganic fluoride (F-) is toxic for brain. The major question for this review was whether an excessive F- intake is causally related to adverse neurological and cognitive health conditions in human beings and animals. The paper systematically and critically summarizes the findings of the studies showing positive associations between F- intoxication and various intellectual defects, as well as of those which attempted to clarify the nature of F- neurotoxicity. Many works provide support for a link between pre- and postnatal F- exposure and structural and functional changes in the central nervous system responsible for neurological and cognitive disorders. The mechanisms suggested to underlie F- neurotoxicity include the disturbances in synaptic transmission and synaptic plasticity, premature death of neurons, altered activities of components of intracellular signaling cascades, impaired protein synthesis, deficit of neurotrophic and transcriptional factors, oxidative stress, metabolic changes, inflammatory processes. However, the majority of works have been performed on laboratory rodents using such F- doses which are never exist in the nature even in the regions of endemic fluorosis. Thus, this kind of treatment is hardly comparable with human exposure even taking into account the higher rate of F- clearance in animals. Of special importance are the data collected on humans chronically consuming excessive F- doses in the regions of endemic fluorosis or contacting with toxic F- compounds at industrial sites, but those works are scarce and often criticized due to low quality. New, expertly performed studies with repeated exposure assessment in independent populations are needed to prove an ability of F- to impair neurological and intellectual development of human beings and to understand the molecular mechanisms implicated in F--induced neurotoxicity.
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Affiliation(s)
- N I Agalakova
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, Saint-Petersburg, Russian Federation
| | - O V Nadei
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, Saint-Petersburg, Russian Federation
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17
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Wei W, Pang S, Sun D. The pathogenesis of endemic fluorosis: Research progress in the last 5 years. J Cell Mol Med 2019; 23:2333-2342. [PMID: 30784186 PMCID: PMC6433665 DOI: 10.1111/jcmm.14185] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 12/03/2018] [Accepted: 01/10/2019] [Indexed: 12/14/2022] Open
Abstract
Fluorine is one of the trace elements necessary for health. It has many physiological functions, and participates in normal metabolism. However, fluorine has paradoxical effects on the body. Many studies have shown that tissues and organs of humans and animals appear to suffer different degrees of damage after long-term direct or indirect exposure to more fluoride than required to meet the physiological demand. Although the aetiology of endemic fluorosis is clear, its specific pathogenesis is inconclusive. In the past 5 years, many researchers have conducted in-depth studies into the pathogenesis of endemic fluorosis. Research in the areas of fluoride-induced stress pathways, signalling pathways and apoptosis has provided further extensive knowledge at the molecular and genetic level. In this article, we summarize the main results.
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Affiliation(s)
- Wei Wei
- Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, China.,Institution of Environmentally Related Diseases, Harbin Medical University, Harbin, China
| | - Shujuan Pang
- Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, China
| | - Dianjun Sun
- Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, China
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18
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Hardeland R. Melatonin and inflammation-Story of a double-edged blade. J Pineal Res 2018; 65:e12525. [PMID: 30242884 DOI: 10.1111/jpi.12525] [Citation(s) in RCA: 272] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 09/10/2018] [Accepted: 09/14/2018] [Indexed: 12/13/2022]
Abstract
Melatonin is an immune modulator that displays both pro- and anti-inflammatory properties. Proinflammatory actions, which are well documented by many studies in isolated cells or leukocyte-derived cell lines, can be assumed to enhance the resistance against pathogens. However, they can be detrimental in autoimmune diseases. Anti-inflammatory actions are of particular medicinal interest, because they are observed in high-grade inflammation such as sepsis, ischemia/reperfusion, and brain injury, and also in low-grade inflammation during aging and in neurodegenerative diseases. The mechanisms contributing to anti-inflammatory effects are manifold and comprise various pathways of secondary signaling. These include numerous antioxidant effects, downregulation of inducible and inhibition of neuronal NO synthases, downregulation of cyclooxygenase-2, inhibition of high-mobility group box-1 signaling and toll-like receptor-4 activation, prevention of inflammasome NLRP3 activation, inhibition of NF-κB activation and upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2). These effects are also reflected by downregulation of proinflammatory and upregulation of anti-inflammatory cytokines. Proinflammatory actions of amyloid-β peptides are reduced by enhancing α-secretase and inhibition of β- and γ-secretases. A particular role in melatonin's actions seems to be associated with the upregulation of sirtuin-1 (SIRT1), which shares various effects known from melatonin and additionally interferes with the signaling by the mechanistic target of rapamycin (mTOR) and Notch, and reduces the expression of the proinflammatory lncRNA-CCL2. The conclusion on a partial mediation by SIRT1 is supported by repeatedly observed inhibitions of melatonin effects by sirtuin inhibitors or knockdown.
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Affiliation(s)
- Rüdiger Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Göttingen, Göttingen, Germany
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19
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Bohush A, Niewiadomska G, Filipek A. Role of Mitogen Activated Protein Kinase Signaling in Parkinson's Disease. Int J Mol Sci 2018; 19:ijms19102973. [PMID: 30274251 PMCID: PMC6213537 DOI: 10.3390/ijms19102973] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 12/31/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder caused by insufficient dopamine production due to the loss of 50% to 70% of dopaminergic neurons. A shortage of dopamine, which is predominantly produced by the dopaminergic neurons within the substantia nigra, causes clinical symptoms such as reduction of muscle mass, impaired body balance, akinesia, bradykinesia, tremors, postural instability, etc. Lastly, this can lead to a total loss of physical movement and death. Since no cure for PD has been developed up to now, researchers using cell cultures and animal models focus their work on searching for potential therapeutic targets in order to develop effective treatments. In recent years, genetic studies have prominently advocated for the role of improper protein phosphorylation caused by a dysfunction in kinases and/or phosphatases as an important player in progression and pathogenesis of PD. Thus, in this review, we focus on the role of selected MAP kinases such as JNKs, ERK1/2, and p38 MAP kinases in PD pathology.
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Affiliation(s)
- Anastasiia Bohush
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland.
| | - Grazyna Niewiadomska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland.
| | - Anna Filipek
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland.
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20
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Fluoride Induces Neuroinflammation and Alters Wnt Signaling Pathway in BV2 Microglial Cells. Inflammation 2018; 40:1123-1130. [PMID: 28405851 DOI: 10.1007/s10753-017-0556-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Fluoride is a common element in nature and our daily life, and excessive intake of this element can cause fluorosis and irreversible brain damage. The toxic effects of fluoride on the central nervous system may be attributed to the release of inflammatory cytokines and ROS. GSK3β is a key protein that modulates NF-κB activity and inflammatory cytokine levels and plays an important role in the Wnt signaling pathway. In this study, we found that fluoride altered the inflammatory status and oxidative stress by inhibiting Wnt signaling pathway activity. This study thus provides a valid basis for the fluorine-induced neuroinflammation injury theory.
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21
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Tu W, Zhang Q, Liu Y, Han L, Wang Q, Chen P, Zhang S, Wang A, Zhou X. Fluoride induces apoptosis via inhibiting SIRT1 activity to activate mitochondrial p53 pathway in human neuroblastoma SH-SY5Y cells. Toxicol Appl Pharmacol 2018; 347:60-69. [PMID: 29609003 DOI: 10.1016/j.taap.2018.03.030] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 03/22/2018] [Accepted: 03/27/2018] [Indexed: 01/08/2023]
Abstract
There has been a great concern about the neurotoxicity of fluoride since it can pass through the blood-brain barrier and accumulate in the brain. It has been suggested that apoptosis plays a vital role in neurotoxicity of fluoride. However, whether p53-mediated apoptotic pathway is involved is still unclear. Our results showed that apoptosis was induced after treatment with 40 and 60 mg/L of NaF for 24 h in human neuroblastoma SH-SY5Y cells. Exposure to 60 mg/L of NaF for 24 h significantly upregulated the levels of p53 and apoptosis-related proteins including PUMA, cytochrome c (cyto c), cleaved caspase-3 and cleaved PARP, whereas downregulated Bcl-2 in SH-SY5Y cells. Meanwhile, fluoride increased p53 nuclear translocation, cyto c release from mitochondria to cytoplasm and mitochondrial translocation of Bax in SH-SY5Y cells. Fluoride-induced increases of apoptotic rates and apoptosis-related protein levels were significantly attenuated by inhibiting p53 transcriptional activity with pifithrin-α. In addition, fluoride inhibited the deacetylase activity of SIRT1 and increased p53 (acetyl K382) level in SH-SY5Y cells. Apoptosis and upregulation of cleaved caspase-3, cleaved PARP and p53 (acetyl K382) induced by fluoride could be ameliorated by SIRT1 overexpression or its activator resveratrol in SH-SY5Y cells. Taken together, our study demonstrates that fluoride induces apoptosis by inhibiting the deacetylase activity of SIRT1 to activate mitochondrial p53 pathway in SH-SY5Y cells, which depends on p53 transcriptional activity. Thus, SIRT1 may be a promising target to protect against neurotoxicity induced by fluoride.
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Affiliation(s)
- Wei Tu
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Qian Zhang
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Yin Liu
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Lianyong Han
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Qin Wang
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Panpan Chen
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Shun Zhang
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Aiguo Wang
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Xue Zhou
- Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China.
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22
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McPherson CA, Zhang G, Gilliam R, Brar SS, Wilson R, Brix A, Picut C, Harry GJ. An Evaluation of Neurotoxicity Following Fluoride Exposure from Gestational Through Adult Ages in Long-Evans Hooded Rats. Neurotox Res 2018; 34:781-798. [PMID: 29404855 PMCID: PMC6077107 DOI: 10.1007/s12640-018-9870-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 01/11/2018] [Accepted: 01/12/2018] [Indexed: 01/04/2023]
Abstract
At elevated levels, fluoride (F-) exposure has been associated with adverse human health effects. In rodents, F- exposure has been reported to induce deficits in motor performance and learning and memory. In this study, we examined Long-Evans hooded male rats maintained on a standard diet (20.5 ppm F-) or a low F- diet (3.24 ppm F-) with drinking water exposure to 0, 10, or 20 ppm F- from gestational day 6 through adulthood. At postnatal day 25, brain F- levels were 0.048 or 0.081 μg/g and femur 235 or 379.8 μg/g for 10 and 20 ppm F-, respectively. Levels increase with age and in adults, levels for plasma were 0.036 or 0.025 μg/ml; for the brain 0.266 or 0.850 μg/g; and for the femur, 681.2 or 993.4 μg/g. At these exposure levels, we observed no exposure-related differences in motor, sensory, or learning and memory performance on running wheel, open-field activity, light/dark place preference, elevated plus maze, pre-pulse startle inhibition, passive avoidance, hot-plate latency, Morris water maze acquisition, probe test, reversal learning, and Y-maze. Serum triiodothyronine (T3), thyroxine (T4), and thyroid stimulating hormone (TSH) levels were not altered as a function of 10 or 20 ppm F- in the drinking water. No exposure-related pathology was observed in the heart, liver, kidney, testes, seminal vesicles, or epididymides. Mild inflammation in the prostate gland was observed at 20 ppm F-. No evidence of neuronal death or glial activation was observed in the hippocampus at 20 ppm F-.
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Affiliation(s)
- Christopher A McPherson
- Neurotoxicology Group, National Toxicology Program Laboratory, National Institute of Environmental Health Sciences, Mail Drop C1-04, P.O. Box 12233, Research Triangle Park, NC, 27709, USA
| | - Guozhu Zhang
- Social & Scientific Systems, Inc, Durham, NC, 27703, USA
| | - Richard Gilliam
- Neurotoxicology Group, National Toxicology Program Laboratory, National Institute of Environmental Health Sciences, Mail Drop C1-04, P.O. Box 12233, Research Triangle Park, NC, 27709, USA
| | - Sukhdev S Brar
- Cellular & Molecular Pathology Branch, Division of the National Toxicology Program, NIEHS, Research Tringle Park, NC, 27709, USA
| | - Ralph Wilson
- Cellular & Molecular Pathology Branch, Division of the National Toxicology Program, NIEHS, Research Tringle Park, NC, 27709, USA
| | - Amy Brix
- Experimental Pathology Laboratories, Research Triangle Park, NC, USA
| | | | - G Jean Harry
- Neurotoxicology Group, National Toxicology Program Laboratory, National Institute of Environmental Health Sciences, Mail Drop C1-04, P.O. Box 12233, Research Triangle Park, NC, 27709, USA.
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23
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Song C, Zhao J, Fu B, Li D, Mao T, Peng W, Wu H, Zhang Y. Melatonin-mediated upregulation of Sirt3 attenuates sodium fluoride-induced hepatotoxicity by activating the MT1-PI3K/AKT-PGC-1α signaling pathway. Free Radic Biol Med 2017; 112:616-630. [PMID: 28912098 DOI: 10.1016/j.freeradbiomed.2017.09.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 08/28/2017] [Accepted: 09/08/2017] [Indexed: 02/06/2023]
Abstract
Mitochondrial reactive oxygen species (ROS) production has been implicated in the pathogenesis of fluoride toxicity in liver. Melatonin, an indolamine synthesized in the pineal gland, was previously shown to protect against sodium fluoride (NaF)-induced hepatotoxicity. This study investigated the protective effects of melatonin pretreatment on NaF-induced hepatotoxicity and elucidates the potential mechanism of melatonin-mediated protection. Reducing mitochondrial ROS by melatonin substantially attenuated NaF-induced NADPH oxidase 4 (Nox4) upregulation and cytotoxicity in L-02 cells. Melatonin exerted its hepatoprotective effects by upregulating Sirtuin 3 (Sirt3) expression level and its activity. Melatonin increased the activity of manganese superoxide dismutase (SOD2) by promoting Sirt3-mediated deacetylation and promoted SOD2 expression through Sirt3-regulated DNA-binding activity of forkhead box O3 (FoxO3a), thus inhibiting the production of mitochondrial ROS induced by NaF. Notably, increased peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) by melatonin activated the Sirt3 expression, which was regulated by an estrogen-related receptor (ERR) binding element (ERRE) mapped to Sirt3 promoter region. Analysis of the cell signaling pathway profiling systems and specific pathway inhibition indicated that melatonin enhances PGC-1α expression by activating the PI3K/AKT signaling pathway. Importantly, inhibition of melatonin receptor (MT)-1 blocked the melatonin-activated PI3K/AKT-PGC-1α-Sirt3 signaling. Mechanistic study revealed that the protective effects of melatonin were associated with down-regulation of JNK1/2 phosphorylation. Our findings provided a theoretical basis that melatonin mitigated NaF-induced hepatotoxicity, which, in part, was mediated through the activation of the Sirt3 pathway.
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Affiliation(s)
- Chao Song
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Jiamin Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Beibei Fu
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Dan Li
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Tingchao Mao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Wei Peng
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Haibo Wu
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Yong Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China.
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Melo CGDS, Perles JVCM, Zanoni JN, Souza SRGD, Santos EX, Leite ADL, Heubel AD, E Souza CO, Souza JGD, Buzalaf MAR. Enteric innervation combined with proteomics for the evaluation of the effects of chronic fluoride exposure on the duodenum of rats. Sci Rep 2017; 7:1070. [PMID: 28432311 PMCID: PMC5430799 DOI: 10.1038/s41598-017-01090-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 03/24/2017] [Indexed: 02/07/2023] Open
Abstract
Ingested fluoride (F) is absorbed mainly in the small intestine, which is controlled by the Enteric Nervous System (ENS). Although important intestinal symptomatology has been described after excessive F exposure, there have been no studies reporting the effects of F on the ENS. In this study, the effects of chronic F exposure were evaluated on the duodenums of rats through proteomic and morphological analyses. Concentrations of 0, 10, or 50 ppm of F were applied to the drinking water for 30 days. Immunofluorescence techniques were performed in the myenteric plexus of the duodenum to detect HuC/D, neuronal nitric oxide (nNOS), vasoactive intestinal peptide (VIP), calcitonin gene related peptide (CGRP), and substance P (SP). The 50 ppm F group presented a significant decrease in the density of nNOS-IR neurons. Significant morphological alterations were also observed in HUC/D-IR and nNOS-IR neurons; VIP-IR, CGRP-IR, and SP-IR varicosities for both groups (10 and 50 ppm F). Proteomic analysis of the duodenum demonstrated alterations in the expression of several proteins, especially those related to important biological processes, such as protein polymerization, which helps to explain the downregulation of many proteins upon exposure to 50 ppm of F.
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Affiliation(s)
| | | | | | | | - Erika Xavier Santos
- Department of Morphophysiological Sciences, State University of Maringá, Paraná, Brazil
| | - Aline de Lima Leite
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | | | - Camila Oliveira E Souza
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | - Juliana Gadelha de Souza
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
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Wang HW, Zhou BH, Cao JW, Zhao J, Zhao WP, Tan PP. Pro-inflammatory Cytokines Are Involved in Fluoride-Induced Cytotoxic Potential in HeLa Cells. Biol Trace Elem Res 2017; 175:98-102. [PMID: 27206670 DOI: 10.1007/s12011-016-0749-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 05/16/2016] [Indexed: 02/02/2023]
Abstract
This study was designed to investigate the pro-inflammatory cytokines and their involvement in the cytotoxic potential of fluoride (F) in HeLa cells. HeLa cells were cultured with varying F concentrations (1-50 mg/L) for 48 h, and treatment effects were analyzed. The viability of HeLa cells was determined with a colorimetric method. The concentrations of IL-1β, IL-2, IL-6, and TNF-a in culture supernatant were measured through enzyme linked immunosorbent assay (ELISA). The mRNA expression levels of IL-1β, IL-2, IL-6 and TNF-a were subjected to transcript analysis and quantified through reverse transcription real-time PCR. Results showed that 10, 20 and 50 mg/L F significantly decreased the viability of HeLa cells incubated for 24 and 48 h. With their cytotoxic effect, the concentrations of IL-1β, IL-2, IL-6, and TNF-a decreased significantly in response to F, especially at 20 and 50 mg/L for 48 h. The mRNA expression levels of IL-1β, IL-2, IL-6, and TNF-a were downregulated at 50 mg/L F for 48 h. Therefore, F inhibited HeLa cell growth; as such, F could be used to alleviate the inhibition of pro-inflammatory cytokine expression.
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Affiliation(s)
- Hong-Wei Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Henan, Luoyang, 471003, People's Republic of China.
| | - Bian-Hua Zhou
- College of Animal Science and Technology, Henan University of Science and Technology, Henan, Luoyang, 471003, People's Republic of China
| | - Jian-Wen Cao
- College of Animal Science and Technology, Henan University of Science and Technology, Henan, Luoyang, 471003, People's Republic of China
| | - Jing Zhao
- College of Animal Science and Technology, Henan University of Science and Technology, Henan, Luoyang, 471003, People's Republic of China
| | - Wen-Peng Zhao
- College of Animal Science and Technology, Henan University of Science and Technology, Henan, Luoyang, 471003, People's Republic of China
| | - Pan-Pan Tan
- College of Animal Science and Technology, Henan University of Science and Technology, Henan, Luoyang, 471003, People's Republic of China
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Cai T, Luo W, Ruan D, Wu YJ, Fox DA, Chen J. The History, Status, Gaps, and Future Directions of Neurotoxicology in China. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:722-732. [PMID: 26824332 PMCID: PMC4892912 DOI: 10.1289/ehp.1409566] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 09/25/2015] [Accepted: 01/15/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND Rapid economic development in China has produced serious ecological, environmental, and health problems. Neurotoxicity has been recognized as a major public health problem. The Chinese government, research institutes, and scientists conducted extensive studies concerning the source, characteristics, and mechanisms of neurotoxicants. OBJECTIVES This paper presents, for the first time, a comprehensive history and review of major sources of neurotoxicants, national bodies/legislation engaged, and major neurotoxicology research in China. METHODS Peer-reviewed research and pollution studies by Chinese scientists from 1991 to 2015 were examined. PubMed, Web of Science and Chinese National Knowledge Infrastructure (CNKI) were the major search tools. RESULTS The central problem is an increased exposure to neurotoxicants from air and water, food contamination, e-waste recycling, and manufacturing of household products. China formulated an institutional framework and standards system for management of major neurotoxicants. Basic and applied research was initiated, and international cooperation was achieved. The annual number of peer-reviewed neurotoxicology papers from Chinese authors increased almost 30-fold since 2001. CONCLUSIONS Despite extensive efforts, neurotoxicity remains a significant public health problem. This provides great challenges and opportunities. We identified 10 significant areas that require major educational, environmental, governmental, and research efforts, as well as attention to public awareness. For example, there is a need to increase efforts to utilize new in vivo and in vitro models, determine the potential neurotoxicity and mechanisms involved in newly emerging pollutants, and examine the effects and mechanisms of mixtures. In the future, we anticipate working with scientists worldwide to accomplish these goals and eliminate, prevent and treat neurotoxicity. CITATION Cai T, Luo W, Ruan D, Wu YJ, Fox DA, Chen J. 2016. The history, status, gaps, and future directions of neurotoxicology in China. Environ Health Perspect 124:722-732; http://dx.doi.org/10.1289/ehp.1409566.
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Affiliation(s)
- Tongjian Cai
- Department of Occupational and Environmental Health, Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi’an, Shaanxi, China
- Department of Epidemiology, College of Preventive Medicine, Third Military Medical University, Chongqing, China
| | - Wenjing Luo
- Department of Occupational and Environmental Health, Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi’an, Shaanxi, China
| | - Diyun Ruan
- Neurotoxicology Lab, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Yi-Jun Wu
- Laboratory of Molecular Toxicology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Donald A. Fox
- College of Optometry,
- Department of Biology and Biochemistry,
- Department of Pharmacological and Pharmaceutical Sciences, and
- Department of Health and Human Performance, University of Houston, Houston, Texas, USA
| | - Jingyuan Chen
- Department of Occupational and Environmental Health, Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi’an, Shaanxi, China
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Trimethyltin-Induced Microglial Activation via NADPH Oxidase and MAPKs Pathway in BV-2 Microglial Cells. Mediators Inflamm 2015. [PMID: 26221064 PMCID: PMC4499416 DOI: 10.1155/2015/729509] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Trimethyltin (TMT) is known as a potent neurotoxicant that causes neuronal cell death and neuroinflammation, particularly in the hippocampus. Microglial activation is one of the prominent pathological features of TMT neurotoxicity. Nevertheless, it remains unclear how microglial activation occurs in TMT intoxication. In this study, we aimed to investigate the signaling pathways in TMT-induced microglial activation using BV-2 murine microglial cells. Our results revealed that TMT generates reactive oxygen species (ROS) and increases the expression of CD11b and nuclear factor-κB- (NF-κB-) mediated nitric oxide (NO) and tumor necrosis factor- (TNF-) α in BV-2 cells. We also observed that NF-κB activation was controlled by p38 and JNK phosphorylation. Moreover, TMT-induced ROS generation occurred via nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in BV-2 cells. Interestingly, treatment with the NADPH oxidase inhibitor apocynin significantly suppressed p38 and JNK phosphorylation and NF-κB activation and ultimately the production of proinflammatory mediators upon TMT exposure. These findings indicate that NADPH oxidase-dependent ROS generation activated p38 and JNK mitogen-activated protein kinases (MAPKs), which then stimulated NF-κB to release proinflammatory mediators in the TMT-treated BV-2 cells.
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Wang C, Nie X, Zhang Y, Li T, Mao J, Liu X, Gu Y, Shi J, Xiao J, Wan C, Wu Q. Reactive oxygen species mediate nitric oxide production through ERK/JNK MAPK signaling in HAPI microglia after PFOS exposure. Toxicol Appl Pharmacol 2015; 288:143-51. [PMID: 26086160 DOI: 10.1016/j.taap.2015.06.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 06/06/2015] [Accepted: 06/12/2015] [Indexed: 12/15/2022]
Abstract
Perfluorooctane sulfonate (PFOS), an emerging persistent contaminant that is commonly encountered during daily life, has been shown to exert toxic effects on the central nervous system (CNS). However, the molecular mechanisms underlying the neurotoxicity of PFOS remain largely unknown. It has been widely acknowledged that the inflammatory mediators released by hyper-activated microglia play vital roles in the pathogenesis of various neurological diseases. In the present study, we examined the impact of PFOS exposure on microglial activation and the release of proinflammatory mediators, including nitric oxide (NO) and reactive oxidative species (ROS). We found that PFOS exposure led to concentration-dependent NO and ROS production by rat HAPI microglia. We also discovered that there was rapid activation of the ERK/JNK MAPK signaling pathway in the HAPI microglia following PFOS treatment. Moreover, the PFOS-induced iNOS expression and NO production were attenuated after the inhibition of ERK or JNK MAPK by their corresponding inhibitors, PD98059 and SP600125. Interestingly, NAC, a ROS inhibitor, blocked iNOS expression, NO production, and activation of ERK and JNK MAPKs, which suggested that PFOS-mediated microglial NO production occurs via a ROS/ERK/JNK MAPK signaling pathway. Finally, by exposing SH-SY5Y cells to PFOS-treated microglia-conditioned medium, we demonstrated that NO was responsible for PFOS-mediated neuronal apoptosis.
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Affiliation(s)
- Cheng Wang
- Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Xiaoke Nie
- Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Yan Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Ting Li
- Department of Labor and Environmental Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Jiamin Mao
- Department of Labor and Environmental Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Xinhang Liu
- Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Yiyang Gu
- Department of Labor and Environmental Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Jiyun Shi
- Department of Labor and Environmental Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Jing Xiao
- Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Chunhua Wan
- Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China
| | - Qiyun Wu
- Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001, People's Republic of China.
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Hardeland R, Cardinali DP, Brown GM, Pandi-Perumal SR. Melatonin and brain inflammaging. Prog Neurobiol 2015; 127-128:46-63. [DOI: 10.1016/j.pneurobio.2015.02.001] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Revised: 10/27/2014] [Accepted: 02/05/2015] [Indexed: 02/07/2023]
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Refsnes M, Skuland T, Låg M, Schwarze PE, Øvrevik J. Differential NF-κB and MAPK activation underlies fluoride- and TPA-mediated CXCL8 (IL-8) induction in lung epithelial cells. J Inflamm Res 2014; 7:169-85. [PMID: 25540590 PMCID: PMC4270361 DOI: 10.2147/jir.s69646] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Different toxic agents have a varying potential to induce the production of the proinflammatory chemokine, CXCL8 (interleukin [IL]-8), in lung cells. A critical question is which mechanisms determine the magnitude and persistence of the CXCL8 responses to different stimuli. To approach this, we compared the potential of the phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA), and sodium fluoride (NaF) to induce CXCL8 responses in A549 cells, with emphasis on the importance of nuclear factor kappa B (NF-κB)- and mitogen-activated protein kinase (MAPK) signaling. Notably, TPA induced a greater release of CXCL8 than did NaF. Furthermore, TPA induced a strong, rapid, but transient upregulation of CXCL8 messenger (m)RNA, whereas NaF induced a weaker, more delayed, but persistent upregulation. With respect to signaling, TPA led to an early, strong, and relatively transient extracellular signal-regulated kinase (ERK)1/2 phosphorylation, and a less marked and even more transient phosphorylation of c-jun-N-terminal kinases (JNK1/2) and p38. In contrast, NaF elicited a lower, but relatively sustained increase in phosphorylation of ERK1/2, and a marked phosphorylation of p38 and JNK1/2, with the JNK1/2 response as most transient. Only ERK1/2 inhibition affected the TPA response, whereas inhibition of all the three MAPK cascades reduced NaF-induced CXCL8 release. TPA also induced an early, marked phosphorylation/translocation of p65 (NF-κB), whereas NaF induced slower, less pronounced effects on p65. The CXCL8 responses by TPA and NaF were reduced by p65-siRNA. In conclusion, all MAPK cascades were involved in NaF-induced CXCL8 release, whereas only ERK1/2 activation was involved in response to TPA. Furthermore, NF-κB activation appeared to be indispensable for CXCL8 induction. The early response, magnitude, and persistency of MAPK and NF-κB signaling seemed to be critical determinants for the potential to induce CXCL8. These findings underscore that a strong, rapid, and relatively transient activation of ERK1/2 in combination with NF-kB may be sufficient for a strong induction of CXCL8, which may exceed the effects of a more moderate ERK1/2 activation in combination with activation of p38, JNK1/2, and NF-κB.
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Affiliation(s)
- Magne Refsnes
- Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway
| | - Tonje Skuland
- Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway
| | - Marit Låg
- Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway
| | - Per E Schwarze
- Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway
| | - Johan Øvrevik
- Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway
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Yue YK, Mo B, Zhao J, Yu YJ, Liu L, Yue CL, Liu W. Neuroprotective Effect of Curcumin Against Oxidative Damage in BV-2 Microglia and High Intraocular Pressure Animal Model. J Ocul Pharmacol Ther 2014; 30:657-64. [PMID: 24963995 DOI: 10.1089/jop.2014.0022] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yan-Kun Yue
- Department of Ophthalmology, Fuxing Hospital, Capital Medical University, Beijing, China
| | - Bin Mo
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Bejing, China
| | - Jun Zhao
- Department of Ophthalmology, Linyi People's Hospital, Linyi City, China
| | - Ya-Jie Yu
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Bejing, China
| | - Lu Liu
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Bejing, China
| | - Chang-Li Yue
- Department of Pathology, Beijing Tongren Hospital, Capital Medical University, Bejing, China
| | - Wu Liu
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Bejing, China
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Lee JY, Yune TY. Ghrelin inhibits oligodendrocyte cell death by attenuating microglial activation. Endocrinol Metab (Seoul) 2014; 29:371-8. [PMID: 25309797 PMCID: PMC4192814 DOI: 10.3803/enm.2014.29.3.371] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 01/16/2014] [Accepted: 02/03/2014] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Recently, we reported the antiapoptotic effect of ghrelin in spinal cord injury-induced apoptotic cell death of oligodendrocytes. However, how ghrelin inhibits oligodendrocytes apoptosis, is still unknown. Therefore, in the present study, we examined whether ghrelin inhibits microglia activation and thereby inhibits oligodendrocyte apoptosis. METHODS Using total cell extracts prepared from BV-2 cells activated by lipopolysaccharide (LPS) with or without ghrelin, the levels of p-p38 phosphor-p38 mitogen-activated protein kinase (p-p38MAPK), phospho-c-Jun N-terminal kinase (pJNK), p-c-Jun, and pro-nerve growth factor (proNGF) were examined by Western blot analysis. Reactive oxygen species (ROS) production was investigated by using dichlorodihydrofluorescein diacetate. To examine the effect of ghrelin on oligodendrocyte cell death, oligodendrocytes were cocultured in transwell chambers of 24-well plates with LPS-stimulated BV-2 cells. After 48 hours incubation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and terminal deoxynucleotidyl transferase 2'-deoxyuridine, 5'-triphosphate nick end labeling staining were assessed. RESULTS Ghrelin treatment significantly decreased levels of p-p38MAPK, p-JNK, p-c-Jun, and proNGF in LPS-stimulated BV-2 cells. ROS production increased in LPS-stimulated BV-2 cells was also significantly inhibited by ghrelin treatment. In addition, ghrelin significantly inhibited oligodendrocyte cell death when cocultured with LPS-stimulated BV-2 cells. CONCLUSION Ghrelin inhibits oligodendrocyte cell death by decreasing proNGF and ROS production as well as p38MAPK and JNK activation in activated microglia as an anti-inflammatory hormone.
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Affiliation(s)
- Jee Youn Lee
- Age-Related and Brain Diseases Research Center, Kyung Hee University School of Medicine, Seoul, Korea
| | - Tae Young Yune
- Age-Related and Brain Diseases Research Center, Kyung Hee University School of Medicine, Seoul, Korea
- Department of Biochemistry and Molecular Biology, Kyung Hee University School of Medicine, Seoul, Korea
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Yang Y, Lee J, Rhee MH, Yu T, Baek KS, Sung NY, Kim Y, Yoon K, Kim JH, Kwak YS, Hong S, Kim JH, Cho JY. Molecular mechanism of protopanaxadiol saponin fraction-mediated anti-inflammatory actions. J Ginseng Res 2014; 39:61-8. [PMID: 25535478 PMCID: PMC4268567 DOI: 10.1016/j.jgr.2014.06.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 06/01/2014] [Accepted: 06/07/2014] [Indexed: 12/24/2022] Open
Abstract
Background Korean Red Ginseng (KRG) is a representative traditional herbal medicine with many different pharmacological properties including anticancer, anti-atherosclerosis, anti-diabetes, and anti-inflammatory activities. Only a few studies have explored the molecular mechanism of KRG-mediated anti-inflammatory activity. Methods We investigated the anti-inflammatory mechanisms of the protopanaxadiol saponin fraction (PPD-SF) of KRG using in vitro and in vivo inflammatory models. Results PPD-SF dose-dependently diminished the release of inflammatory mediators [nitric oxide (NO), tumor necrosis factor-α, and prostaglandin E2], and downregulated the mRNA expression of their corresponding genes (inducible NO synthase, tumor necrosis factor-α, and cyclooxygenase-2), without altering cell viability. The PPD-SF-mediated suppression of these events appeared to be regulated by a blockade of p38, c-Jun N-terminal kinase (JNK), and TANK (TRAF family member-associated NF-kappa-B activator)-binding kinase 1 (TBK1), which are linked to the activation of activating transcription factor 2 (ATF2) and interferon regulatory transcription factor 3 (IRF3). Moreover, this fraction also ameliorated HCl/ethanol/-induced gastritis via suppression of phospho-JNK2 levels. Conclusion These results strongly suggest that the anti-inflammatory action of PPD-SF could be mediated by a reduction in the activation of p38-, JNK2-, and TANK-binding-kinase-1-linked pathways and their corresponding transcription factors (ATF2 and IRF3).
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Affiliation(s)
- Yanyan Yang
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
| | - Jongsung Lee
- Department of Dermatological Health Management, Eulji University, Seongnam, Korea
| | - Man Hee Rhee
- College of Veterinary Medicine, Kyungpook National University, Daegu, Korea
| | - Tao Yu
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
| | - Kwang-Soo Baek
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
| | - Nak Yoon Sung
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
| | - Yong Kim
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
| | - Keejung Yoon
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
| | - Ji Hye Kim
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
| | - Yi-Seong Kwak
- Ginseng Corporation Central Research Institute, Daejeon, Korea
| | - Sungyoul Hong
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
| | - Jong-Hoon Kim
- Department of Veterinary Physiology, College of Veterinary Medicine, Biosafety Research Institute, Chonbuk National University, Jeonju, Korea
- Corresponding author. Department of Veterinary Physiology, College of Veterinary Medicine, Biosafety Research Institute, Chonbuk National University, 567 Baekje-daero, Jeonju 561-756, Korea
| | - Jae Youl Cho
- Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea
- Corresponding author. Department of Genetic Engineering, Sungkyunkwan University, 2066 Seobu-ro, Suwon 440-746, Korea.
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Geng Y, Qiu Y, Liu X, Chen X, Ding Y, Liu S, Zhao Y, Gao R, Wang Y, He J. Sodium fluoride activates ERK and JNK via induction of oxidative stress to promote apoptosis and impairs ovarian function in rats. JOURNAL OF HAZARDOUS MATERIALS 2014; 272:75-82. [PMID: 24681588 DOI: 10.1016/j.jhazmat.2014.03.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Revised: 03/02/2014] [Accepted: 03/03/2014] [Indexed: 06/03/2023]
Abstract
The toxicity of sodium fluoride (NaF) to female fertility is currently recognized; however, the mechanisms are unclear. Previously, we reported a reduction in successful pregnancy rates, ovarian atrophy and dysfunction following exposure to NaF. The purpose of this study was to elucidate the underlying molecular mechanisms. Female Sprague-Dawley rats (10 rats/group) received 100 or 200mg/L NaF in their drinking water for 6 months or were assigned to an untreated control group. Apoptotic indices and oxidative stress indicators in blood and ovarian tissue were analyzed following sacrifice. The results confirmed the NaF-induced ovarian apoptosis, with concomitant activation of oxidative stress. Further investigations in ovarian granular cells showed that exposure to NaF activated extracellular regulated protein kinase (ERK) and c-Jun NH2 kinase (JNK), disrupting the ERK and JNK signaling pathways, while p38 and PI3K remained unchanged. These data demonstrated that oxidative stress may play a key role in NaF-induced ovarian dysfunction by activating the apoptotic ERK and JNK signaling pathways.
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Affiliation(s)
- Yanqing Geng
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Yiwen Qiu
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Xueqing Liu
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Xuemei Chen
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Yubin Ding
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Shangjing Liu
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Yi Zhao
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Rufei Gao
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Yingxiong Wang
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
| | - Junlin He
- Laboratory of Reproductive Biology, School of Public Health and Management, Chongqing Medical University, Box 197, No. 1 Yixueyuan Road, Yuzhong District, 400016 Chongqing, PR China.
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Epigallocatechin gallate supplementation protects against renal injury induced by fluoride intoxication in rats: Role of Nrf2/HO-1 signaling. Toxicol Rep 2014; 1:12-30. [PMID: 28962222 PMCID: PMC5598207 DOI: 10.1016/j.toxrep.2014.01.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 01/16/2014] [Accepted: 01/16/2014] [Indexed: 01/18/2023] Open
Abstract
Fluoride intoxication generates free radicals, causing oxidative stress that plays a critical role in the progression of nephropathy. In the present study, we hypothesized that epigallocatechin gallate (EGCG), found in green tea, protects the kidneys of rats treated with fluoride by preventing oxidative stress, inflammation, and apoptosis. Pretreatment of fluoride-treated rats with EGCG resulted in a significant normalization of creatinine clearance and levels of urea, uric acid, and creatinine. Fluoride intoxication significantly increased renal oxidative stress markers and decreased the levels of renal enzymatic and non-enzymatic antioxidants. In addition, renal NO, TNF-α, IL-6 and NF-κB were also increased in the renal tissue of fluoride-treated rats. Further, EGCG pretreatment produced a significant improvement in renal antioxidant status and reduced lipid peroxidation, protein carbonylation and the levels of inflammatory markers in fluoride-treated kidney. Similarly, mRNA and protein analyses showed that EGCG pretreatment normalized the renal expression of Nrf2/Keap1 and its downstream regulatory proteins in fluoride-treated rat kidney. EGCG also effectively attenuated fluoride-induced renal apoptosis by the up-regulation of anti-apoptotic proteins such as Bcl-2 and down-regulation of Bax, caspase-3, caspase-9 and cytochrome c. Histology and immunohistochemical observations of Kim-1 provided further evidence that EGCG effectively protects the kidney from fluoride-mediated oxidative damage. These results suggest that EGCG ameliorates fluoride-induced oxidative renal injury by activation of the Nrf2/HO-1 pathway.
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Key Words
- ATPase, adenosine triphosphatase
- Bax, B-cell associated X protein
- Bcl-2, B-cell lymphoma 2
- CAT, catalase
- EDTA, ethylenediaminetetraacetic acid
- EGCG, epigallocatechin gallate
- Fluoride
- G6PD, glucose 6-phosphate dehydrogenase
- GAPDH, glyceraldehyde 3 phosphate dehydrogenase
- GCSH, γ-glutamylcysteine synthetase heavy subunit
- GPx, glutathione peroxidase
- GR, glutathione reductase
- GST, glutathione S-transferease
- GSTM, glutathione S-transferase Mu
- HO-1, heme oxygenase-1
- IL-6, interleukin-6
- Keap-1, Kelch-like ECH-associated protein 1
- Kidney
- Kim-1, kidney injury molecule-1
- LOOH, lipid hydroperoxide
- NF-kB, Nuclear factor kappa B
- NaF, sodium fluoride
- Nrf2, nuclear factor erythroid-2 related factor-2
- Oxidative stress
- PC, protein carbonyl
- ROS/RNS, reactive oxygen species/reactive nitrogen species
- Rat
- Reactive oxygen species
- SOD, superoxide dismutase
- TBARS, thiobarbituric acid reactive substances
- TNF-α, tumor necrosis factor-α
- TSH, total sulfhydryl groups
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