Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms...Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed woundhealing assay and Transwell? motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations(10^(-10) and/or 10^(-9) mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mR NA expression of two promigratory genes, including cell division cycle 42(CDC42) and matrix metalloproteinase 2(MMP2)was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor(AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels.展开更多
Several cohort studies have reported that dioxin and dioxin-like polychlorinated biphenyls might impair the nervous system and lead to neurological or neurodegenerative diseases in the elder people, but there is limit...Several cohort studies have reported that dioxin and dioxin-like polychlorinated biphenyls might impair the nervous system and lead to neurological or neurodegenerative diseases in the elder people, but there is limited research on the involved mechanism. By using microarray analysis, we figured out the differentially expressed genes between brain samples from SD rats after low-dose（0.1 μg/（kg？bw）） dioxin exposure for six months and controls. To investigate the function changes in the course of dioxin exposure, Gene Ontology（GO） annotation and Kyoto Encyclopedia of Genes and Genomes（KEGG） pathway analysis were performed on the differentially expressed genes. And the changes of several picked genes have been verified by real-time PCR. A total of 145 up-regulated and 64 down-regulated genes were identified. The metabolic processes, interleukin-1 secretion and production were significantly associated with the differentially expressed genes. And the genes regulated by dioxin also clustered to cholinergic synapse and long-term potentiation. Candidate biomarker genes such as egr1, gad2, gabrb3, abca1, ccr5 and pycard may be toxicological targets for dioxin. Furthermore, synaptic plasticity and neuro-immune system may be two principal affected areas by dioxin.展开更多
Dioxin can cause a series of neural toxicological effects. Micro RNAs(mi Rs) play important roles in regulating nervous system function and mediating cellular responses to environmental pollutants, such as dioxin. Hsa...Dioxin can cause a series of neural toxicological effects. Micro RNAs(mi Rs) play important roles in regulating nervous system function and mediating cellular responses to environmental pollutants, such as dioxin. Hsa-mi R-146 b-5 p appears to be involved in neurodegenerative diseases and brain tumors. However, little is known about effects of dioxin on the expression of hsa-mi R-146 b-5 p. We found that the hsa-mi R-146 b-5 p expression and its promoter activity were significantly increased in dioxin treated SK-N-SH cells, a human-derived neuroblastoma cell line. Potential roles of hsa-mi R-146 b-5 p in mediating neural toxicological effects of dioxin may be due to the regulation of certain target genes. We further confirmed that hsa-mi R-146 b-5 p significantly suppressed acetylcholinesterase(ACh E) activity and targeted the3′-untranslated region of the ACh E T subunit, which has been down-regulated in dioxin treated SK-N-SH cells. Functional bioinformatic analysis showed that the known and predicted target genes of hsa-mi R-146 b-5 p were involved in some brain functions or cyto-toxicities related to known dioxin effects, including synapse transmission, in which ACh E may serve as a responsive gene for mediating the effect.展开更多
Developing high-performance visible-light driven photocatalyst(λ≥420 nm)makes significance for the efficient utilization of solar energy.Mass production and easy recycling are equally important for the practical app...Developing high-performance visible-light driven photocatalyst(λ≥420 nm)makes significance for the efficient utilization of solar energy.Mass production and easy recycling are equally important for the practical application of powdery photocatalyst.However,it is challenging to meet the above requirements at the same time.In this work,we develop an efficient visible-light responsive layered oxyiodide CdBiO_(2)I nanosheets prepared by a facile direct precipitation method at ambient atmosphere,and demonstrate its upgradable features well fitting potential application.CdBiO_(2)I has a layered crystal structure consisting of[CdBiO_(2)^(+)layer and I^(-)single layer,differing from that of BiOI composed of[BiO_(2)]^(2+)layer and I^(-)double layers.It displays an absorption edge of 520 nm in visible region,with a band gap of 2.52 eV CdBiO_(2)I has a large intrinsic effective mass difference of hole/electron,exceeding BiOI by 8-fold,which results in much higher charge separation efficiency and production of more reactive species(superoxide radicals and holes).The degradation efficiency of CdBiO_(2)I nanosheets for tetracycline hydrochloride reaches 84%under the visible light irradiation within 1 h,in which the degradation rate is 10 times that of BiOI.In addition,mass production(12 g catalyst at one time)and immobilization onto porous polyurethane foam of CdBiO_(2)I powder are also demonstrated,which indicates the scalable properties and easy recovery of the catalyst,highlighting the advantages of the current preparation method and prefiguring its potential in practical applications.This work may enlighten future research on the exploitation of solar-driven catalyst with high efficiency and strong practical applicability.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Nos.XDB14030401,XDB14030402)the Natural Science Foundation of China (Nos.21377160,21525730)Tianjin Municipal Science and Technology Commission (No.14JCQNJC11300)
文摘Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed woundhealing assay and Transwell? motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations(10^(-10) and/or 10^(-9) mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mR NA expression of two promigratory genes, including cell division cycle 42(CDC42) and matrix metalloproteinase 2(MMP2)was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor(AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels.
基金supported by grants from the Natural Science Foundation of China(Nos.21407171,21377160,21525730)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB14030400)
文摘Several cohort studies have reported that dioxin and dioxin-like polychlorinated biphenyls might impair the nervous system and lead to neurological or neurodegenerative diseases in the elder people, but there is limited research on the involved mechanism. By using microarray analysis, we figured out the differentially expressed genes between brain samples from SD rats after low-dose（0.1 μg/（kg？bw）） dioxin exposure for six months and controls. To investigate the function changes in the course of dioxin exposure, Gene Ontology（GO） annotation and Kyoto Encyclopedia of Genes and Genomes（KEGG） pathway analysis were performed on the differentially expressed genes. And the changes of several picked genes have been verified by real-time PCR. A total of 145 up-regulated and 64 down-regulated genes were identified. The metabolic processes, interleukin-1 secretion and production were significantly associated with the differentially expressed genes. And the genes regulated by dioxin also clustered to cholinergic synapse and long-term potentiation. Candidate biomarker genes such as egr1, gad2, gabrb3, abca1, ccr5 and pycard may be toxicological targets for dioxin. Furthermore, synaptic plasticity and neuro-immune system may be two principal affected areas by dioxin.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Nos.XDB14030401,XDB14030402)the National Natural Science Foundation of China(Nos.21177150,21377160,21525730)
文摘Dioxin can cause a series of neural toxicological effects. Micro RNAs(mi Rs) play important roles in regulating nervous system function and mediating cellular responses to environmental pollutants, such as dioxin. Hsa-mi R-146 b-5 p appears to be involved in neurodegenerative diseases and brain tumors. However, little is known about effects of dioxin on the expression of hsa-mi R-146 b-5 p. We found that the hsa-mi R-146 b-5 p expression and its promoter activity were significantly increased in dioxin treated SK-N-SH cells, a human-derived neuroblastoma cell line. Potential roles of hsa-mi R-146 b-5 p in mediating neural toxicological effects of dioxin may be due to the regulation of certain target genes. We further confirmed that hsa-mi R-146 b-5 p significantly suppressed acetylcholinesterase(ACh E) activity and targeted the3′-untranslated region of the ACh E T subunit, which has been down-regulated in dioxin treated SK-N-SH cells. Functional bioinformatic analysis showed that the known and predicted target genes of hsa-mi R-146 b-5 p were involved in some brain functions or cyto-toxicities related to known dioxin effects, including synapse transmission, in which ACh E may serve as a responsive gene for mediating the effect.
基金supported by the National Natural Science Foundation of China(No.52272244)the Fundamental Research Funds for the Central Universities(2652022202).
文摘Developing high-performance visible-light driven photocatalyst(λ≥420 nm)makes significance for the efficient utilization of solar energy.Mass production and easy recycling are equally important for the practical application of powdery photocatalyst.However,it is challenging to meet the above requirements at the same time.In this work,we develop an efficient visible-light responsive layered oxyiodide CdBiO_(2)I nanosheets prepared by a facile direct precipitation method at ambient atmosphere,and demonstrate its upgradable features well fitting potential application.CdBiO_(2)I has a layered crystal structure consisting of[CdBiO_(2)^(+)layer and I^(-)single layer,differing from that of BiOI composed of[BiO_(2)]^(2+)layer and I^(-)double layers.It displays an absorption edge of 520 nm in visible region,with a band gap of 2.52 eV CdBiO_(2)I has a large intrinsic effective mass difference of hole/electron,exceeding BiOI by 8-fold,which results in much higher charge separation efficiency and production of more reactive species(superoxide radicals and holes).The degradation efficiency of CdBiO_(2)I nanosheets for tetracycline hydrochloride reaches 84%under the visible light irradiation within 1 h,in which the degradation rate is 10 times that of BiOI.In addition,mass production(12 g catalyst at one time)and immobilization onto porous polyurethane foam of CdBiO_(2)I powder are also demonstrated,which indicates the scalable properties and easy recovery of the catalyst,highlighting the advantages of the current preparation method and prefiguring its potential in practical applications.This work may enlighten future research on the exploitation of solar-driven catalyst with high efficiency and strong practical applicability.
