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Guan R, Wang T, Dong X, Du K, Li J, Zhao F, Xu J, Li B, Zheng G, Shen X, Cao B, Wang J, Aschner M, Liu M, Chen R. Effects of co-exposure to lead and manganese on learning and memory deficits. J Environ Sci (China) 2022; 121:65-76. [PMID: 35654517 PMCID: PMC9163452 DOI: 10.1016/j.jes.2021.09.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 06/15/2023]
Abstract
Lead (Pb) and manganese (Mn) are common neurotoxins. However, individuals are subject to co-exposures in real life, and it is therefore important to study these metals in combination. Weaning Sprague-Dawley rats were given ad libitum access to drinking water solutions containing Pb (100 mg/L), Mn (2.5 mg/mL) or a mixture, and each treatment had its own minocycline (50 mg/(kg•day)) supplement group. The results showed a significant difference in spatial memory and induction levels of hippocampal long-term potentiation (LTP) in all exposure groups when compared with controls. The combined-exposure group exhibited the most pronounced effect when compared with each of the single-metal exposure groups. Microglia displayed activation at day 3 after exposure alone or in combination, while astrocytes showed activation at day 5, accompanied by decreased expression levels of GLAST, GLT-1, and GS. Furthermore, the levels of glutamate in the synaptic cleft increased significantly. When microglial activation was inhibited by minocycline, the activation of astrocytes and the expression of GLAST, GLT-1, and GS were both reversed. In addition, upon minocycline treatment, hippocampal LTP impairment and cognitive injury were significantly alleviated in each of the exposure groups. These results suggest that combined exposure to Pb and Mn can cause greater effects on cognition and synaptic plasticity when compared to single-metal exposure groups. The reason may involve abnormal activation of microglia leading to excessive regulation of astrocytes, resulting in glutamate reuptake dysfunction in astrocytes and leading to perturbed cognition and synaptic plasticity.
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Affiliation(s)
- Ruili Guan
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Tao Wang
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Xiaoru Dong
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Kejun Du
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Juan Li
- Department of Physiology, National Key Discipline of Cell Biology, Fourth Military Medical University, Xi'an 710032, China
| | - Fang Zhao
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Jie Xu
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Bin Li
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Gang Zheng
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Xuefeng Shen
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Baohua Cao
- School of Nursing, Fourth Military Medical University, Xi'an 710032, China
| | - Jing Wang
- School of Nursing, Fourth Military Medical University, Xi'an 710032, China
| | - Michael Aschner
- School of Nursing, Fourth Military Medical University, Xi'an 710032, China; Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA; IM Sechenov First Moscow State Medical University, Moscow, Russia
| | - Mingchao Liu
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China; School of Nursing, Fourth Military Medical University, Xi'an 710032, China.
| | - Rui Chen
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
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Nie X, Cheng G, Wang M, Wang C, Du K. [Survey and evaluation of heavy metal in the major vegetables in Shaanxi Province]. Wei Sheng Yan Jiu 2015; 44:775-779. [PMID: 26591774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To evaluate the contamination condition of the Pb, Cd, Hg and As in ten kinds of vegetables in Shaanxi Province. METHODS The Pb and Cd contents were determined by inductively coupled plasma mass spectrometry, and the As contents were determined by hydride generation-atomic fluorescence spectrometry, and the Hg contents were determined by mercury vapourmeter. One factor contamination index was employed to evaluate the metal pollution situation of different types of vegetables. Moreover, the health risk after intake of those heavy metals through vegetables were described. RESULTS In ten kinds of vegetables of Shaanxi Province, the Pb contents in cowpea reached the alertness level, while the contents of Cd, Hg and As were below the safety level. What' s more, the contents of the Pb, Cd, Hg and As were below the safety level in other nine vegetables, and the over standard rate of were Hg > Pb > Cd > As. CONCLUSION The contamination extents of Pb, Cd, Hg and As in ten kinds of vegetables in Shaanxi Province were low.
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Wei J, Du K, Cai Q, Ma L, Jiao Z, Tan J, Xu Z, Li J, Luo W, Chen J, Gao J, Zhang D, Huang C. Lead induces COX-2 expression in glial cells in a NFAT-dependent, AP-1/NFκB-independent manner. Toxicology 2014; 325:67-73. [PMID: 25193092 DOI: 10.1016/j.tox.2014.08.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 08/28/2014] [Accepted: 08/30/2014] [Indexed: 12/22/2022]
Abstract
Epidemiologic studies have provided solid evidence for the neurotoxic effect of lead for decades of years. In view of the fact that children are more vulnerable to the neurotoxicity of lead, lead exposure has been an urgent public health concern. The modes of action of lead neurotoxic effects include disturbance of neurotransmitter storage and release, damage of mitochondria, as well as induction of apoptosis in neurons, cerebrovascular endothelial cells, astroglia and oligodendroglia. Our studies here, from a novel point of view, demonstrates that lead specifically caused induction of COX-2, a well known inflammatory mediator in neurons and glia cells. Furthermore, we revealed that COX-2 was induced by lead in a transcription-dependent manner, which relayed on transcription factor NFAT, rather than AP-1 and NFκB, in glial cells. Considering the important functions of COX-2 in mediation of inflammation reaction and oxidative stress, our studies here provide a mechanistic insight into the understanding of lead-associated inflammatory neurotoxicity effect via activation of pro-inflammatory NFAT3/COX-2 axis.
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Affiliation(s)
- Jinlong Wei
- Zhejiang Provincial Key Laboratory for Technology & Application of Model Organisms, School of Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China; Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987, USA
| | - Kejun Du
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987, USA; Department of Occupational and Environmental Health and Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Qinzhen Cai
- Zhejiang Provincial Key Laboratory for Technology & Application of Model Organisms, School of Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Lisha Ma
- Zhejiang Provincial Key Laboratory for Technology & Application of Model Organisms, School of Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Zhenzhen Jiao
- Zhejiang Provincial Key Laboratory for Technology & Application of Model Organisms, School of Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Jinrong Tan
- Zhejiang Provincial Key Laboratory for Technology & Application of Model Organisms, School of Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Zhou Xu
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987, USA
| | - Jingxia Li
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987, USA
| | - Wenjin Luo
- Department of Occupational and Environmental Health and Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Jingyuan Chen
- Department of Occupational and Environmental Health and Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Jimin Gao
- Zhejiang Provincial Key Laboratory for Technology & Application of Model Organisms, School of Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
| | - Dongyun Zhang
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987, USA.
| | - Chuanshu Huang
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987, USA.
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An J, Cai T, Che H, Yu T, Cao Z, Liu X, Zhao F, Jing J, Shen X, Liu M, Du K, Chen J, Luo W. The changes of miRNA expression in rat hippocampus following chronic lead exposure. Toxicol Lett 2014; 229:158-66. [DOI: 10.1016/j.toxlet.2014.06.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 05/24/2014] [Accepted: 06/01/2014] [Indexed: 11/24/2022]
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Du K, Yu Y, Zhang D, Luo W, Huang H, Chen J, Gao J, Huang C. NFκB1 (p50) suppresses SOD2 expression by inhibiting FoxO3a transactivation in a miR190/PHLPP1/Akt-dependent axis. Mol Biol Cell 2013; 24:3577-83. [PMID: 24068327 PMCID: PMC3826995 DOI: 10.1091/mbc.e13-06-0343] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
This study reports a novel function of p50 in its regulation of SOD2 transcription via an NFκB-independent pathway. p50-regulated FoxO3a phosphorylation and transactivation contributes to SOD2 transcription, and p50–down-regulated PHLPP1 translation via miR190 is responsible for activation of Akt and FoxO3a. The biological functions of nuclear factor κB1 (NFκB1; p50) have not been studied as often as those of other members of the NFκB family due to its lack of a transcriptional domain. Our recent studies showed that p50 functions as an apoptotic mediator via its inhibition of GADD45α protein degradation and increase in p53 protein translation. Here we report a novel function of p50 in its regulation of superoxide dismutase 2 (SOD2) transcription via an NFκB-independent pathway. We find that deletion of p50 in mouse embryonic fibroblasts (MEFs; p50−/−) up-regulates SOD2 expression at both protein and mRNA levels. SOD2 promoter–driven luciferase is also up-regulated in p50−/− cells compared with wild-type (WT) MEF (p50+/+) cells, suggesting p50 regulation of SOD2 at the transcriptional level. Our results also show that p50 deficiency specifically results in down-regulation of phosphorylation and increased transactivation of FoxO3a compared with WT cells. Further studies indicate that p50–down-regulated FoxO3a phosphorylation is mediated by activated Akt via up-regulation of microRNA 190 (miR190), in turn inhibiting PH domain and leucine-rich repeat protein phosphatase 1 (PHLPP1) translation. Together our studies identify a novel p50 function in the regulation of SOD2 transcription by modulating the miR190/PHLPP1/Akt-FoxO3a pathway, which provides significant insight into the physiological function of p50.
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Affiliation(s)
- Kejun Du
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987 Department of Occupational and Environmental Health, School of Public Health, Fourth Military Medical University, Shanxi 710032, China Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325035, China
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Zhang Z, Bai X, Du K, Huang Y, Wang W, Zhao Y, Pei Y, Mu J, Han H, Hu S, Li S, Dong H, Lu Y, Hou L, Xiong L. Activation of cholinergic anti-inflammatory pathway contributes to the protective effects of 100% oxygen inhalation on zymosan-induced generalized inflammation in mice. J Surg Res 2011; 174:e75-83. [PMID: 22261596 DOI: 10.1016/j.jss.2011.10.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 10/14/2011] [Accepted: 10/26/2011] [Indexed: 10/15/2022]
Abstract
BACKGROUND The 100% oxygen inhalation has been demonstrated to have a protective effect on mice with zymosan-induced generalized inflammation. However, the underlying mechanism is largely unknown. The present study was designed to explore the role of the cholinergic anti-inflammatory pathway in this animal model. METHODS Oxygen inhalation was given to mice at 4 and 12 h after zymosan injection. One group of mice underwent vagotomy 7 d before zymosan injection. The other two groups of mice either received nicotinic acetylcholine receptor (nAChR) antagonist mecamylamine, or α7 nicotinic acetylcholine receptor (α7nAChR) antagonist methyllycaconitine 30 min before oxygen was given. RESULTS The 100% oxygen treatment significantly decreased the serum level of TNF-α and increased the serum level of IL-10. The pathologic changes of the heart, lung, liver, and kidney were attenuated, as well as the dysfunction of liver and kidney. The 7-d survival rate of zymosan-challenged mice was also improved. Conversely, all these protective effects caused by pure oxygen treatment were abolished in those animals that received anti-cholinergic treatments. CONCLUSIONS The cholinergic anti-inflammatory pathway may be involved in the 100% oxygen protective mechanism against zymosan-induced generalized inflammation in mice.
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Affiliation(s)
- Zishen Zhang
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, PR China
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Cai T, Che H, Yao T, Chen Y, Huang C, Zhang W, Du K, Zhang J, Cao Y, Chen J, Luo W. Manganese induces tau hyperphosphorylation through the activation of ERK MAPK pathway in PC12 cells. Toxicol Sci 2010; 119:169-77. [PMID: 20937724 DOI: 10.1093/toxsci/kfq308] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Manganese has long been known to induce neurological degenerative disorders. Emerging evidence indicates that hyperphosphorylated tau is associated with neurodegenerative diseases, but whether such hyperphosphorylation plays a role in manganese-induced neurotoxicity remains unclear. To fill this gap, we investigated the effects of manganese on tau phosphorylation in PC12 cells. In our present research, treatment of cells with manganese increased the phosphorylation of tau at Ser199, Ser202, Ser396, and Ser404 as detected by Western blot. Moreover, this manganese-induced tau phosphorylation paralleled the activation of extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK). The mitogen-activated protein kinase kinase-1 (MEK1) inhibitor PD98059, which inhibits the activation of ERK MAPK, partially attenuated manganese-induced tau hyperphosphorylation and cytotoxicity. Moreover, the activation of ERK MAPK was involved in the activation of glycogen synthase kinase-3β (GSK-3β) kinase, which also contributed to the hyperphosphorylation of tau and the cytotoxicity in PC12 cells induced by manganese. Taken together, we found for the first time that the exposure to manganese can cause the hyperphosphorylation of tau, which may be connected with the activation of ERK MAPK.
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Affiliation(s)
- Tongjian Cai
- Department of Occupational and Environmental Health, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
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Cai T, Yao T, Zheng G, Chen Y, Du K, Cao Y, Shen X, Chen J, Luo W. Manganese induces the overexpression of α-synuclein in PC12 cells via ERK activation. Brain Res 2010; 1359:201-7. [PMID: 20735995 DOI: 10.1016/j.brainres.2010.08.055] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2010] [Revised: 08/16/2010] [Accepted: 08/17/2010] [Indexed: 11/28/2022]
Abstract
Manganese has been known to induce neurological disorders. In the present study, we determined the effect of manganese on the expression of α-synuclein in PC12 cells and its role in manganese-induced cytotoxicity. We also investigated the relationship between α-synuclein expression and the change of ERK1/2 MAPK activity. In our research, manganese exposure induced the overexpression of α-synuclein, while siRNA knockdown of α-synuclein reversed manganese-induced cytotoxicity. Furthermore, manganese induced the activation of ERK1/2 MAPK. The MEK1 inhibitor PD98059, which inhibits the activation of ERK MAPK, attenuated the overexpression of α-synuclein and the cytotoxicity induced by manganese. In conclusion, our studies show that manganese may induce the overexpression of α-synuclein via ERK1/2 activation, which may play a role in manganese-induced cytotoxicity.
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Affiliation(s)
- Tongjian Cai
- Department of Occupational and Environmental Health, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
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Du K, Chen Y, Dai Z, Bi Y, Cai T, Hou L, Chai Y, Song Q, Chen S, Luo W, Chen J. Molecular cloning and functional characterization of a mouse gene upregulated by lipopolysaccharide treatment reveals alternative splicing. Biochem Biophys Res Commun 2010; 391:267-71. [PMID: 19913514 DOI: 10.1016/j.bbrc.2009.11.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Accepted: 11/07/2009] [Indexed: 12/27/2022]
Abstract
Treatment of mouse cells with lipopolysaccharide (LPS) potently initiates an inflammatory response, but the underlying mechanisms are unclear. We therefore sought to characterize cDNA sequences of a new mouse LPS-responsive gene, and to evaluate the effects of MLrg. Full-length cDNAs were obtained from LPS-treated NIH3T3 cells. We report that the MLrg gene produces two alternative splice products (GenBank Accession Nos. DQ316984 and DQ320011), respectively, encoding MLrgW and MLrgS polypeptides. Both proteins contain zinc finger and leucine zipper domains and are thus potential regulators of transcription. Expression of MLrgW and MLrgS were robustly upregulated following LPS treatment, and the proteins were localized predominantly in the nuclear membrane and cytoplasm. In stable transfectants over-expressing MLrgW the proportion of cells in G1 phase was significantly reduced, while in cells over-expressing MLrgS the proportion of cells in G2 was significantly increased; both proteins are thus potential regulators of cell cycle progression. Upregulation of MLrgW and MLrgS may be an important component of the LPS inflammatory pathway and of the host response to infection with GNB.
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Affiliation(s)
- Kejun Du
- Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, PR China
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Luo W, Chen Y, Liu M, Du K, Zheng G, Cai T, Zhang W, Zhao F, Yao T, Yang R, Chen J. EB1089 induces Skp2-dependent p27 accumulation, leading to cell growth inhibition and cell cycle G1 phase arrest in human hepatoma cells. Cancer Invest 2009; 27:29-37. [PMID: 19160095 DOI: 10.1080/07357900802438569] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
EB1089 exhibits a high level of antiproliferative activity against various tumors. However, it is not known whether the mechanism of EB1089 induced the growth inhibition in human hepatic-carcinoma. Here we found that EB1089 significantly reduced cell growth in human hepatoma cells (Hep-G2) and blocked Hep-G2 cell-associated tumor formation in nude mice. The growth inhibition was linked to cell cycle G1 phase arrest by the accumulation of p27 and a reduction of Skp2. Knockdown of Skp2 reversed the p27 induction and G1 arrest. Taken together, our data indicate that EB1089 inhibitory activity is associated with alteration of cell cycle checkpoints through Skp2-dependent p27 induction in Hep-G2 cells.
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Affiliation(s)
- Wenjing Luo
- Department of Occupational and Environmental Health, Faculty of Preventive Medicine, Fourth Military Medical University, Shaanxi, China
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Du K, Chai Y, Hou L, Chang W, Chen S, Luo W, Cai T, Zhang X, Chen N, Chen Y, Chen J. Over-expression and siRNA of a novel environmental lipopolysaccharide-responding gene on the cell cycle of the human hepatoma-derived cell line HepG2. Toxicology 2007; 243:303-10. [PMID: 18068885 DOI: 10.1016/j.tox.2007.10.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2007] [Revised: 10/17/2007] [Accepted: 10/20/2007] [Indexed: 12/12/2022]
Abstract
Lipopolysaccharide (LPS) is the toxic determinant for Gram-negative bacterium infection. The individual response to LPS was related to its gene background. It is necessary to identify new molecules and signaling transduction pathways about LPS. The present study was undertaken to evaluate the effects of a novel environmental lipopolysaccharide-responding (Elrg) gene on the regulation of proliferation and cell cycle of the hepatoma-derived cell line, HepG2. By means of RT-PCR, the new molecule of Elrg was generated from a human dental pulp cell cDNA library. Expression level of Elrg in HepG2 cells was remarkably upgraded by the irritation of LPS. Localization of Elrg in HepG2 cells was positioned mainly in cytoplasm. HepG2 cells were markedly arrested in the G1 phase by over-expressing Elrg. The percentage of HepG2 cells in G1 phase partly decreased after Elrg-siRNA. In conclusion, Elrg is probably correlative with LPS responding. Elrg is probably a new protein in cytoplasm which plays an important role in regulating cell cycle. The results will deepen our understanding about the potential effects of Elrg on the human hepatoma-derived cell line HepG2.
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Affiliation(s)
- Kejun Du
- Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, PR China
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Cai T, Yao T, Li Y, Chen Y, Du K, Chen J, Luo W. Proteasome inhibition is associated with manganese-induced oxidative injury in PC12 cells. Brain Res 2007; 1185:359-65. [PMID: 17996855 DOI: 10.1016/j.brainres.2007.09.075] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 09/22/2007] [Accepted: 09/24/2007] [Indexed: 01/25/2023]
Abstract
Manganese has been known to induce neurological disorders similar to Parkinson's disease. The dysfunction of ubiquitin-proteasome system, a pathway involved in detoxification and targeting of damaged proteins, is connected with Parkinson's disease pathogenesis. Oxidative stress may be involved in Parkinson's disease, and may also be associated with manganese-induced neurotoxicity. In the present study, we determined the effects of manganese chloride on proteasome activity in PC12 cells. Furthermore, we investigated the relationship between oxidative stress and the change of proteasome activity. The proteasome activity of PC12 cells was measured by an ELISA method. Selective oxidative stress parameters, including malondialdehyde and protein carbonyl, were measured in PC12 cells treated with manganese chloride. Cell survival and apoptosis were measured by methyl thiazolyl tetrazolium and terminal transferase-mediated dUTP nick end-labeling. In our research, manganese chloride exposure inhibited the activity of proteasome and induced oxidative stress. Both can be reversed by antioxidant agent N-acetylcysteine. N-acetylcysteine also inhibited the cytotoxicity induced by manganese chloride. In conclusion, our results imply that proteasome inhibition may be associated with manganese-induced cytotoxicity in dopaminergic neurons, which may be connected with oxidative damage.
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Affiliation(s)
- Tongjian Cai
- Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, China
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Dai ZM, Chen SM, Du KJ, Chen NC, Song QH, Luo WJ, Chen JY. [Expression of mouse lipopolysaccharide response protein LRP in E. coli and preparation of rabbit anti-mLRP serum]. Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2006; 22:371-3, 376. [PMID: 16643803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
AIM To express mouse lipopolysaccharide response protein (mLRP) and prepare rabbit anti-mLRP serum. METHODS The predicted mouse lrp cDNA sequence was obtained by splicing homologous ESTs by comparing human lrp cDNA with mouse ESTs. Then the primers were designed. mlrp cDNA from NIH3T3 cells stimulated with lipopolysaccharide (LPS) was amplified by RT-PCR and was cloned into prokaryotic expression vector pTAT to construct recombinant expression vector pTAT-mlrp. The His-TAT-mLRP fusion protein was expressed in E. coli BL21(DE3) and was used to immunize the rabbits to get rabbit anti-mLRP serum. The anti-serum was purified by the acetone precipitation method. The specificity of the rabbit anti-mLRP serum was determined by Western blot. RESULTS The predicted length of mlrp cDNA was 1905 bp. The encoding region of the cloned mlrp cDNA, 1554 bp, was inserted into pTAT. The His-TAT-mLRP fusion protein was expressed successfully in E. coli. The rabbit anti-mLRP serum was prepared by immunizing the rabbit with mLRP protein. CONCLUSION The successful expression of mLRP and the preparation of rabbit anti-mLRP serum lays the foundation for further study of the function of mLRP.
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Affiliation(s)
- Zhong-ming Dai
- Department of Biochemistry and Molecular Biology, Fourth Military Medical University, Xi'an 710032, China.
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Chang WH, Xu DZ, Yan YP, Du KJ, Men K, Zhang JX, Wang JJ, Xu JQ, Zhang ED, Liu C, Sun FM. [Study on the presence of hepatitis B virus in first-trimester villi in pregnant women with hepatitis B surface antigen positive]. Zhonghua Fu Chan Ke Za Zhi 2005; 40:376-9. [PMID: 16008886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
OBJECTIVE To observe the presence of hepatitis B virus (HBV) in first-trimester villi cells from pregnant women carrying HBsAg. METHODS Immunohistochemical streptavidin-biotin peroxidase complex (SABC) staining with monoclonal HBsAg, hepatitis B core antigen (HBcAg) and PCR, in situ hybridization were used for detection of HBV infection markers in villi. Positive villi ultramicrostructures were observed with transmission electron microscope. RESULTS HBV was detected in 8 of 25 villi of HBsAg positive pregnant women, the positive rate was 32%. HBsAg was located in the decidual cell, trophoblastic cell and villous mesenchymal cell. HBV analog was detected in rough endoplasmic reticulum of trophoblastic cell. CONCLUSIONS HBV may infect villous cells in first-trimester pregnancy. It would be impossible for HBV to transmit the desmosomes.
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Affiliation(s)
- Wen-hui Chang
- Department of Epidemiology, Fourth Military Medical University, Xi'an 710032, China
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Liu CL, Dou KF, Zhu BF, Zang XX, Chai YB, Du KJ, Chen SM. [Cloning, expression and antitumor effect of mouse costimulatory molecule 4-1BBL]. Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2004; 20:118-22. [PMID: 15182637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
AIM To clone mouse 4-1BBL gene, construct its eukaryotic expression vector, and evaluate antitumor activity of the expression product. METHODS RT-PCR was used to amplify mouse 4-1BBL gene from total RNA of C57BL/6 splenocytes stimulated by PHA. Then m4-1BBL cDNA was subcloned into eukaryotic expression vector pcDNA3.1(+) and transfected into mouse hepatocellular carcinoma cell line Hepa1-6. The expression of m4-1BBL in transfected cells was detected by RT-PCR, indirect immunofluorescence staining, and flow cytometry. Non-adherent splenocytes from non-immunized C57BL/6 mice were incubated with mitomycin-treated non-transfected Hepa1-6(Hepa1-6-wt) or transfected Hepa1-6 cells (Hepal-6-m4-1BBL), respectively. Then the lymphocytes were tested for cytotoxic activity to Hepa1-6-wt cells. RESULTS The Hepa1-6 cells transfected by pcDNA3.1(+)-m4-1BBL could efficiently express m4-1BBL. As compared with Hepa1-6-wt cells,Hepa1-6-m4-1BBL cells could induce more efficiently cytotoxic activity of lymphocytes to Hepa1-6-wt cells (P<0.01). CONCLUSION The expression of m4-1BBL by tumor cells is effective in inducing antitumor immune response.
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Affiliation(s)
- Cheng-li Liu
- Department of Hepatobiliary Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
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