Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's dis...Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's disease-related dementia.Our previous study identified the upregulation of microRNA-502-3p(miR-502-3p)and downregulation of GABA type A receptor subunitα-1 in Alzheimer's disease synapses.This study investigated a new molecular relationship between miR-502-3p and GABAergic synapse function.In vitro studies were perfo rmed using the mouse hippocampal neuronal cell line HT22 and miR-502-3p agomiRs and antagomiRs.In silico analysis identified multiple binding sites of miR-502-3p at GABA type A receptor subunitα-1 mRNA.Luciferase assay confirmed that miR-502-3p targets the GABA type A receptor subunitα-1 gene and suppresses the luciferase activity.Furthermore,quantitative reve rse transcription-polymerase chain reaction,miRNA in situ hybridization,immunoblotting,and immunostaining analysis confirmed that overexpression of miR-502-3p reduced the GABA type A receptor subunitα-1 level,while suppression of miR-502-3p increased the level of GABA type A receptor subunitα-1 protein.Notably,as a result of the overexpression of miR-502-3p,cell viability was found to be reduced,and the population of necrotic cells was found to be increased.The whole cell patch-clamp analysis of human-GABA receptor A-α1/β3/γ2L human embryonic kidney(HEK)recombinant cell line also showed that overexpression of miR-502-3p reduced the GABA current and overall GABA function,suggesting a negative correlation between miR-502-3p levels and GABAergic synapse function.Additionally,the levels of proteins associated with Alzheimer s disease were high with miR-502-3p overexpression and reduced with miR-502-3p suppression.The present study provides insight into the molecular mechanism of regulation of GABAergic synapses by miR-502-3p.We propose that micro-RNA,in particular miR-502-3p,could be a potential therapeutic to rget to modulate GABAergic synapse function in neurological disorders,including Alzheimer's disease and Alzheimer's diseaserelated dementia.展开更多
Background Asthma is a chronic inflammatory disease characterized by reversible bronchial constriction, pulmonary inflammation and airway remodeling. Current standard therapies for asthma provide symptomatic control, ...Background Asthma is a chronic inflammatory disease characterized by reversible bronchial constriction, pulmonary inflammation and airway remodeling. Current standard therapies for asthma provide symptomatic control, but fail to target the underlying disease pathology. Furthermore, no therapeutic agent is effective in preventing airway remodeling. A substantial amount of evidence suggests that statins have anti-inflammatory properties and immunomodulatory activity. In this study, we investigated the effect of rosuvastatin on airway inflammation and its inhibitory mechanism in mucus hypersecretion in a murine model of chronic asthma. Methods BALB/c mice were sensitized and challenged by ovalbumin to induce asthma. The recruitment of inflammatory cells into bronchoalveolar lavage fluid （BALF） and the lung tissues were measured by Diff-Quik staining and hematoxylin and eosin （H＆E） staining. ELISA was used for measuring the levels of IL-4, IL-5, IL-13 and TNF-a in BALE Periodic acid-Schiff （PAS） staining was used for mucus secretion. Gamma-aminobutyric acid type A receptor （GABAAR） β2 expression was measured by means of immunohistochemistry, reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting. Results Rosuvastatin reduced the number of total inflammatory cells, lymphocytes, macrophages, neutrophils, and eosinophils recruited into BALF, the levels of IL-4, IL-5, IL-13 and TNF-a in BALF, along with the histological mucus index （HMI） and GABAAR 132 expression. Changes occurred in a dose-dependent manner. Conclusions Based on its ability to reduce the inflammatory response and mucus hypersecretion by regulating GABAAR activity in a murine model of chronic asthma, rosuvastatin may be a useful therapeutic agent for treatment of asthma.展开更多
Background:Mounting evidence,consistent with our previous study,showed thatγ-aminobutyric acid type A receptor(GABAAR)played an indispensable role in airway inflammation and mucus hypersecretion in asthma.Monocyte ch...Background:Mounting evidence,consistent with our previous study,showed thatγ-aminobutyric acid type A receptor(GABAAR)played an indispensable role in airway inflammation and mucus hypersecretion in asthma.Monocyte chemotactic protein-inducing protein 1(MCPIP1)was a key negative regulator of inflammation.Recent studies showed that inflammation was largely suppressed by enhanced MCPIP1 expression in many inflammatory diseases.However,the role and potential mechanism of MCPIP1 in airway inflammation and mucus hypersecretion in asthma were still not well studied.This study was to explore the role of MCPIP1 in asthmatic airway inflammation and mucus hypersecretion in both mice and BEAS-2B cells,and its potential mechanism.Methods:In vivo,mice were sensitized and challenged by ovalbumin(OVA)to induce asthma.Airway inflammation and mucus secretion were analyzed.In vitro,BEAS-2B cells were chosen.Interleukin(IL)-13 was used to stimulate inflammation and mucus hypersecretion in cells.MCPIP1 Lentiviral vector(LA-MCPIP1)and plasmid-MCPIP1 were used to up-regulate MCPIP1 in lung and cells,respectively.MCP-1,thymic stromal lymphopoietin(TSLP),mucin 5AC(MUC5AC),MCPIP1,and GABAARβ2 expressions were measured in both lung and BEAS-2B cells.Immunofluorescence staining was performed to observe the expression of GABAARβ2 in cells.Results:MCPIP1 was up-regulated by LA-MCPIP1(P<0.001)and plasmid-MCPIP1(P<0.001)in lung and cells,respectively.OVA-induced airway inflammation and mucus hypersecretion,OVA-enhanced MCP-1,TSLP,MUC5AC,and GABAARβ2 expressions,and OVA-reduced MCPIP1 were significantly blunted by LA-MCPIP1 in mice(all P<0.001).IL-13-enhanced MCP-1,TSLP,MUC5AC,and GABAARβ2 expressions,and IL-13-reduced MCPIP1 were markedly abrogated by plasmid-MCPIP1 in BEAS-2B cells(all P<0.001).Conclusion:The results of this study suggested that OVA and IL-13-induced airway inflammation and mucus hypersecretion were negatively regulated by MCPIP1 in both lung and BEAS-2B cells,involving GABAAR signaling pathway.展开更多
Neurosteroids are rapidly emerging as important new therapies in neuropsychiatry, with one such agent, brexanolone, already approved for treatment of postpartum depression, and others on the horizon. These steroids ha...Neurosteroids are rapidly emerging as important new therapies in neuropsychiatry, with one such agent, brexanolone, already approved for treatment of postpartum depression, and others on the horizon. These steroids have unique properties, including neuroprotective effects that could benefit a wide range of brain illnesses including depression, anxiety, epilepsy, and neurodegeneration. Over the past 25 years, our group has developed ex vivo rodent models to examine factors contributing to several forms of neurodegeneration in the retina. In the course of this work, we have developed a model of acute closed angle glaucoma that involves incubation of ex vivo retinas under hyperbaric conditions and results in neuronal and axonal changes that mimic glaucoma. We have used this model to determine neuroprotective mechanisms that could have therapeutic implications. In particular, we have focused on the role of both endogenous and exogenous neurosteroids in modulating the effects of acute high pressure. Endogenous allopregnanolone, a major stress-activated neurosteroid in the brain and retina, helps to prevent severe pressure-induced retinal excitotoxicity but is unable to protect against degenerative changes in ganglion cells and their axons under hyperbaric conditions. However, exogenous allopregnanolone, at a pharmacological concentration, completely preserves retinal structure and does so by combined effects on gamma-aminobutyric acid type A receptors and stimulation of the cellular process of macroautophagy. Surprisingly, the enantiomer of allopregnanolone, which is inactive at gamma-aminobutyric acid type A receptors, is equally retinoprotective and acts primarily via autophagy. Both enantiomers are also equally effective in preserving retinal structure and function in an in vivo glaucoma model. These studies in the retina have important implications for the ongoing development of allopregnanolone and other neurosteroids as therapeutics for neuropsychiatric illnesses.展开更多
Background: Electroacupuncture (EA) has been shown to attenuate airway inflammation in asthmatic mice;however, the underlying mechanism is not fully understood. Studies have shown that EA can significantly increase th...Background: Electroacupuncture (EA) has been shown to attenuate airway inflammation in asthmatic mice;however, the underlying mechanism is not fully understood. Studies have shown that EA can significantly increase the inhibitory neurotransmitter γ-aminobutyric acid (GABA) content in mice, and can also increase the expression level of GABA type A receptor (GABAAR). Furthermore, activating GABAAR may relieve inflammation in asthma by suppressing toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor-kappa B (NF-κB) signaling pathway. Therefore, this study aimed to investigate the role of GABAergic system and TLR4/MyD88/NF-κB signaling pathway in asthmatic mice treated with EA. Methods: A mouse model of asthma was established, and a series of methods including Western blot and histological staining assessment were employed to detect the level of GABA, and expressions of GABAAR and TLR4/MyD88/NF-κB in lung tissue. In addition, GABAAR antagonist was used to further validate the role and mechanism of GABAergic system in mediating the therapeutic effect of EA in asthma. Results: The mouse model of asthma was established successfully, and EA was verified to alleviate airway inflammation in asthmatic mice. The release of GABA and the expression of GABAAR were significantly increased in asthmatic mice treated with EA compared with untreated asthmatic mice ( P < 0.01), and the TLR4/MyD88/NF-κB signaling pathway was down-regulated. Moreover, inhibition of GABAAR attenuated the beneficial effects of EA in asthma, including the regulation of airway resistance and inflammation, as well as the inhibitory effects on TLR4/MyD88/NF-κB signaling pathway. Conclusion: Our findings suggest that GABAergic system may be involved in mediating the therapeutic effect of EA in asthma, possibly by suppressing the TLR4/MyD88/NF-κB signaling pathway.展开更多
基金supported by the National Institute on Aging (NIA)National Institutes of Health (NIH)+3 种基金Nos.K99AG065645,R00AG065645R00AG065645-04S1 (to SK)NIH research grants,NINDS,No.R01 NS115834NINDS/NIA,No.R01 NS115834-02S1 (to LG)。
文摘Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's disease-related dementia.Our previous study identified the upregulation of microRNA-502-3p(miR-502-3p)and downregulation of GABA type A receptor subunitα-1 in Alzheimer's disease synapses.This study investigated a new molecular relationship between miR-502-3p and GABAergic synapse function.In vitro studies were perfo rmed using the mouse hippocampal neuronal cell line HT22 and miR-502-3p agomiRs and antagomiRs.In silico analysis identified multiple binding sites of miR-502-3p at GABA type A receptor subunitα-1 mRNA.Luciferase assay confirmed that miR-502-3p targets the GABA type A receptor subunitα-1 gene and suppresses the luciferase activity.Furthermore,quantitative reve rse transcription-polymerase chain reaction,miRNA in situ hybridization,immunoblotting,and immunostaining analysis confirmed that overexpression of miR-502-3p reduced the GABA type A receptor subunitα-1 level,while suppression of miR-502-3p increased the level of GABA type A receptor subunitα-1 protein.Notably,as a result of the overexpression of miR-502-3p,cell viability was found to be reduced,and the population of necrotic cells was found to be increased.The whole cell patch-clamp analysis of human-GABA receptor A-α1/β3/γ2L human embryonic kidney(HEK)recombinant cell line also showed that overexpression of miR-502-3p reduced the GABA current and overall GABA function,suggesting a negative correlation between miR-502-3p levels and GABAergic synapse function.Additionally,the levels of proteins associated with Alzheimer s disease were high with miR-502-3p overexpression and reduced with miR-502-3p suppression.The present study provides insight into the molecular mechanism of regulation of GABAergic synapses by miR-502-3p.We propose that micro-RNA,in particular miR-502-3p,could be a potential therapeutic to rget to modulate GABAergic synapse function in neurological disorders,including Alzheimer's disease and Alzheimer's diseaserelated dementia.
基金This study was partially supported by the National Natural Science Foundation of China （No. 30971303）.
文摘Background Asthma is a chronic inflammatory disease characterized by reversible bronchial constriction, pulmonary inflammation and airway remodeling. Current standard therapies for asthma provide symptomatic control, but fail to target the underlying disease pathology. Furthermore, no therapeutic agent is effective in preventing airway remodeling. A substantial amount of evidence suggests that statins have anti-inflammatory properties and immunomodulatory activity. In this study, we investigated the effect of rosuvastatin on airway inflammation and its inhibitory mechanism in mucus hypersecretion in a murine model of chronic asthma. Methods BALB/c mice were sensitized and challenged by ovalbumin to induce asthma. The recruitment of inflammatory cells into bronchoalveolar lavage fluid （BALF） and the lung tissues were measured by Diff-Quik staining and hematoxylin and eosin （H＆E） staining. ELISA was used for measuring the levels of IL-4, IL-5, IL-13 and TNF-a in BALE Periodic acid-Schiff （PAS） staining was used for mucus secretion. Gamma-aminobutyric acid type A receptor （GABAAR） β2 expression was measured by means of immunohistochemistry, reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting. Results Rosuvastatin reduced the number of total inflammatory cells, lymphocytes, macrophages, neutrophils, and eosinophils recruited into BALF, the levels of IL-4, IL-5, IL-13 and TNF-a in BALF, along with the histological mucus index （HMI） and GABAAR 132 expression. Changes occurred in a dose-dependent manner. Conclusions Based on its ability to reduce the inflammatory response and mucus hypersecretion by regulating GABAAR activity in a murine model of chronic asthma, rosuvastatin may be a useful therapeutic agent for treatment of asthma.
基金supported by grants from the National Natural Science Foundation of China for Young Scholar(No.81801484)China Postdoctoral Science Foundation(No.2014M552369)+1 种基金Natural Science Foundation of Guangdong Province(No.2017A030310286)Scientific Research Project of Guangzhou(No.201707010282)。
文摘Background:Mounting evidence,consistent with our previous study,showed thatγ-aminobutyric acid type A receptor(GABAAR)played an indispensable role in airway inflammation and mucus hypersecretion in asthma.Monocyte chemotactic protein-inducing protein 1(MCPIP1)was a key negative regulator of inflammation.Recent studies showed that inflammation was largely suppressed by enhanced MCPIP1 expression in many inflammatory diseases.However,the role and potential mechanism of MCPIP1 in airway inflammation and mucus hypersecretion in asthma were still not well studied.This study was to explore the role of MCPIP1 in asthmatic airway inflammation and mucus hypersecretion in both mice and BEAS-2B cells,and its potential mechanism.Methods:In vivo,mice were sensitized and challenged by ovalbumin(OVA)to induce asthma.Airway inflammation and mucus secretion were analyzed.In vitro,BEAS-2B cells were chosen.Interleukin(IL)-13 was used to stimulate inflammation and mucus hypersecretion in cells.MCPIP1 Lentiviral vector(LA-MCPIP1)and plasmid-MCPIP1 were used to up-regulate MCPIP1 in lung and cells,respectively.MCP-1,thymic stromal lymphopoietin(TSLP),mucin 5AC(MUC5AC),MCPIP1,and GABAARβ2 expressions were measured in both lung and BEAS-2B cells.Immunofluorescence staining was performed to observe the expression of GABAARβ2 in cells.Results:MCPIP1 was up-regulated by LA-MCPIP1(P<0.001)and plasmid-MCPIP1(P<0.001)in lung and cells,respectively.OVA-induced airway inflammation and mucus hypersecretion,OVA-enhanced MCP-1,TSLP,MUC5AC,and GABAARβ2 expressions,and OVA-reduced MCPIP1 were significantly blunted by LA-MCPIP1 in mice(all P<0.001).IL-13-enhanced MCP-1,TSLP,MUC5AC,and GABAARβ2 expressions,and IL-13-reduced MCPIP1 were markedly abrogated by plasmid-MCPIP1 in BEAS-2B cells(all P<0.001).Conclusion:The results of this study suggested that OVA and IL-13-induced airway inflammation and mucus hypersecretion were negatively regulated by MCPIP1 in both lung and BEAS-2B cells,involving GABAAR signaling pathway.
基金supported by MH101874, MH114866, MH122379 from the National Institute of Mental Health (to CFZ)the Taylor Family Institute for Innovative Psychiatric Research and the Bantly Foundation (to CFZ)。
文摘Neurosteroids are rapidly emerging as important new therapies in neuropsychiatry, with one such agent, brexanolone, already approved for treatment of postpartum depression, and others on the horizon. These steroids have unique properties, including neuroprotective effects that could benefit a wide range of brain illnesses including depression, anxiety, epilepsy, and neurodegeneration. Over the past 25 years, our group has developed ex vivo rodent models to examine factors contributing to several forms of neurodegeneration in the retina. In the course of this work, we have developed a model of acute closed angle glaucoma that involves incubation of ex vivo retinas under hyperbaric conditions and results in neuronal and axonal changes that mimic glaucoma. We have used this model to determine neuroprotective mechanisms that could have therapeutic implications. In particular, we have focused on the role of both endogenous and exogenous neurosteroids in modulating the effects of acute high pressure. Endogenous allopregnanolone, a major stress-activated neurosteroid in the brain and retina, helps to prevent severe pressure-induced retinal excitotoxicity but is unable to protect against degenerative changes in ganglion cells and their axons under hyperbaric conditions. However, exogenous allopregnanolone, at a pharmacological concentration, completely preserves retinal structure and does so by combined effects on gamma-aminobutyric acid type A receptors and stimulation of the cellular process of macroautophagy. Surprisingly, the enantiomer of allopregnanolone, which is inactive at gamma-aminobutyric acid type A receptors, is equally retinoprotective and acts primarily via autophagy. Both enantiomers are also equally effective in preserving retinal structure and function in an in vivo glaucoma model. These studies in the retina have important implications for the ongoing development of allopregnanolone and other neurosteroids as therapeutics for neuropsychiatric illnesses.
基金supported a grant from the Scientific Research Fund of China–Japan Friendship Hospital(No.2017-RC-3).
文摘Background: Electroacupuncture (EA) has been shown to attenuate airway inflammation in asthmatic mice;however, the underlying mechanism is not fully understood. Studies have shown that EA can significantly increase the inhibitory neurotransmitter γ-aminobutyric acid (GABA) content in mice, and can also increase the expression level of GABA type A receptor (GABAAR). Furthermore, activating GABAAR may relieve inflammation in asthma by suppressing toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor-kappa B (NF-κB) signaling pathway. Therefore, this study aimed to investigate the role of GABAergic system and TLR4/MyD88/NF-κB signaling pathway in asthmatic mice treated with EA. Methods: A mouse model of asthma was established, and a series of methods including Western blot and histological staining assessment were employed to detect the level of GABA, and expressions of GABAAR and TLR4/MyD88/NF-κB in lung tissue. In addition, GABAAR antagonist was used to further validate the role and mechanism of GABAergic system in mediating the therapeutic effect of EA in asthma. Results: The mouse model of asthma was established successfully, and EA was verified to alleviate airway inflammation in asthmatic mice. The release of GABA and the expression of GABAAR were significantly increased in asthmatic mice treated with EA compared with untreated asthmatic mice ( P < 0.01), and the TLR4/MyD88/NF-κB signaling pathway was down-regulated. Moreover, inhibition of GABAAR attenuated the beneficial effects of EA in asthma, including the regulation of airway resistance and inflammation, as well as the inhibitory effects on TLR4/MyD88/NF-κB signaling pathway. Conclusion: Our findings suggest that GABAergic system may be involved in mediating the therapeutic effect of EA in asthma, possibly by suppressing the TLR4/MyD88/NF-κB signaling pathway.
