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Sun H, Yang T, Simon R, Xiong ZG, Leng T. Cholestane-3β,5α,6β-Triol Inhibits Acid-Sensing Ion Channels and Reduces Acidosis-Mediated Ischemic Brain Injury. Stroke 2024. [PMID: 38660789 DOI: 10.1161/strokeaha.124.046963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 01/11/2024] [Accepted: 03/25/2024] [Indexed: 04/26/2024]
Abstract
BACKGROUND Activation of the acid-sensing ion channels (ASICs) by tissue acidosis, a common feature of brain ischemia, contributes to ischemic brain injury, while blockade of ASICs results in protection. Cholestane-3β,5α,6β-triol (Triol), a major cholesterol metabolite, has been demonstrated as an endogenous neuroprotectant; however, the mechanism underlying its neuroprotective activity remains elusive. In this study, we tested the hypothesis that inhibition of ASICs is a potential mechanism. METHODS The whole-cell patch-clamp technique was used to examine the effect of Triol on ASICs heterogeneously expressed in Chinese hamster ovary cells and ASICs endogenously expressed in primary cultured mouse cortical neurons. Acid-induced injury of cultured mouse cortical neurons and middle cerebral artery occlusion-induced ischemic brain injury in wild-type and ASIC1 and ASIC2 knockout mice were studied to examine the protective effect of Triol. RESULTS Triol inhibits ASICs in a subunit-dependent manner. In Chinese hamster ovary cells, it inhibits homomeric ASIC1a and ASIC3 without affecting ASIC1β and ASIC2a. In cultured mouse cortical neurons, it inhibits homomeric ASIC1a and heteromeric ASIC1a-containing channels. The inhibition is use-dependent but voltage- and pH-independent. Structure-activity relationship analysis suggests that hydroxyls at the 5 and 6 positions of the A/B ring are critical functional groups. Triol alleviates acidosis-mediated injury of cultured mouse cortical neurons and protects against middle cerebral artery occlusion-induced brain injury in an ASIC1a-dependent manner. CONCLUSIONS Our study identifies Triol as a novel ASIC inhibitor, which may serve as a new pharmacological tool for studying ASICs and may also be developed as a potential drug for treating stroke.
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Affiliation(s)
- Huawei Sun
- Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA
| | - Tao Yang
- Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA
| | - Roger Simon
- Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA
| | - Zhi-Gang Xiong
- Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA
| | - Tiandong Leng
- Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA
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Armstrong A, Yang T, Leng T, Xiong ZG. Inhibition of ASIC1a Improves Behavioral Recovery after Stroke. eNeuro 2024; 11:ENEURO.0341-23.2023. [PMID: 38233146 PMCID: PMC10866329 DOI: 10.1523/eneuro.0341-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 09/05/2023] [Revised: 10/19/2023] [Accepted: 10/26/2023] [Indexed: 01/19/2024] Open
Abstract
Stroke continues to be a leading cause of death and long-term disabilities worldwide, despite extensive research efforts. The failure of multiple clinical trials raises the need for continued study of brain injury mechanisms and novel therapeutic strategies for ischemic stroke. The contribution of acid-sensing ion channel 1a (ASIC1a) to neuronal injury during the acute phase of stroke has been well studied; however, the long-term impact of ASIC1a inhibition on stroke recovery has not been established. The present study sought to bridge part of the translational gap by focusing on long-term behavioral recovery after a 30 min stroke in mice that had ASIC1a knocked out or inhibited by PcTX1. The neurological consequences of stroke in mice were evaluated before and after the stroke using neurological deficit score, open field, and corner turn test over a 28 d period. ASIC1a knock-out and inhibited mice showed improved neurological scores more quickly than wild-type control and vehicle-injected mice after the stroke. ASIC1a knock-out mice also recovered from mobility deficits in the open field test more quickly than wild-type mice, while PcTX1-injected mice did not experience significant mobility deficits at all after the stroke. In contrast to vehicle-injected mice that showed clear-sidedness bias in the corner turn test after stroke, PcTX1-injected mice never experienced significant-sidedness bias at all. This study supports and extends previous work demonstrating ASIC1a as a potential therapeutic target for the treatment of ischemic stroke.
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Affiliation(s)
- Ariel Armstrong
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310
| | - Tao Yang
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310
| | - Tiandong Leng
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310
| | - Zhi-Gang Xiong
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310
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Liu X, Guo C, Leng T, Fan Z, Mai J, Chen J, Xu J, Li Q, Jiang B, Sai K, Yang W, Gu J, Wang J, Sun S, Chen Z, Zhong Y, Liang X, Chen C, Cai J, Lin Y, Liang J, Hu J, Yan G, Zhu W, Yin W. Differential regulation of H3K9/H3K14 acetylation by small molecules drives neuron-fate-induction of glioma cell. Cell Death Dis 2023; 14:142. [PMID: 36805688 PMCID: PMC9941105 DOI: 10.1038/s41419-023-05611-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 01/20/2023] [Accepted: 01/23/2023] [Indexed: 02/22/2023]
Abstract
Differentiation therapy using small molecules is a promising strategy for improving the prognosis of glioblastoma (GBM). Histone acetylation plays an important role in cell fate determination. Nevertheless, whether histone acetylation in specific sites determines GBM cells fate remains to be explored. Through screening from a 349 small molecule-library, we identified that histone deacetylase inhibitor (HDACi) MS-275 synergized with 8-CPT-cAMP was able to transdifferentiate U87MG GBM cells into neuron-like cells, which were characterized by cell cycle arrest, rich neuron biomarkers, and typical neuron electrophysiology. Intriguingly, acetylation tags of histone 3 at lysine 9 (H3K9ac) were decreased in the promoter of multiple oncogenes and cell cycle genes, while ones of H3K9ac and histone 3 at lysine 14 (H3K14ac) were increased in the promoter of neuron-specific genes. We then compiled a list of genes controlled by H3K9ac and H3K14ac, and proved that it is a good predictive power for pathologic grading and survival prediction. Moreover, cAMP agonist combined with HDACi also induced glioma stem cells (GSCs) to differentiate into neuron-like cells through the regulation of H3K9ac/K14ac, indicating that combined induction has the potential for recurrence-preventive application. Furthermore, the combination of cAMP activator plus HDACi significantly repressed the tumor growth in a subcutaneous GSC-derived tumor model, and temozolomide cooperated with the differentiation-inducing combination to prolong the survival in an orthotopic GSC-derived tumor model. These findings highlight epigenetic reprogramming through H3K9ac and H3K14ac as a novel approach for driving neuron-fate-induction of GBM cells.
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Affiliation(s)
- Xincheng Liu
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China ,grid.284723.80000 0000 8877 7471Department of Emergency Medicine, Guangdong Cardiovascular Institute, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510080 P. R. China
| | - Cui Guo
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Tiandong Leng
- grid.9001.80000 0001 2228 775XDepartment of Neuroscience, Morehouse School of Medicine, Atlanta, GA 30310 USA
| | - Zhen Fan
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Jialuo Mai
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Jiehong Chen
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Jinhai Xu
- grid.12981.330000 0001 2360 039XGuangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Qianyi Li
- grid.12981.330000 0001 2360 039XGuangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Bin Jiang
- grid.12981.330000 0001 2360 039XGuangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Ke Sai
- grid.488530.20000 0004 1803 6191Department of Neurosurgery/Neuro-oncology, Sun Yat-sen University Cancer Center, Guangzhou, 510060 P. R. China ,grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060 P. R. China
| | - Wenzhuo Yang
- grid.488530.20000 0004 1803 6191Department of Neurosurgery/Neuro-oncology, Sun Yat-sen University Cancer Center, Guangzhou, 510060 P. R. China ,grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060 P. R. China
| | - Jiayu Gu
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Jingyi Wang
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Shuxin Sun
- grid.488530.20000 0004 1803 6191Department of Neurosurgery/Neuro-oncology, Sun Yat-sen University Cancer Center, Guangzhou, 510060 P. R. China ,grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060 P. R. China
| | - Zhijie Chen
- grid.488530.20000 0004 1803 6191Department of Neurosurgery/Neuro-oncology, Sun Yat-sen University Cancer Center, Guangzhou, 510060 P. R. China ,grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060 P. R. China
| | - Yingqian Zhong
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Xuanming Liang
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Chaoxin Chen
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Jing Cai
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Yuan Lin
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Jiankai Liang
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Jun Hu
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Guangmei Yan
- grid.12981.330000 0001 2360 039XDepartment of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 P. R. China
| | - Wenbo Zhu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, P. R. China.
| | - Wei Yin
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, P. R. China.
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Bao J, Guo Z, He J, Leng T, Wei Z, Wang C, Chen F. Semen parameters and sex hormones as affected by SARS-CoV-2 infection: A systematic review. Prog Urol 2022; 32:1431-1439. [PMID: 36153222 PMCID: PMC9468308 DOI: 10.1016/j.purol.2022.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 07/31/2022] [Accepted: 09/05/2022] [Indexed: 11/23/2022]
Abstract
Background Impaired semen quality and reproductive hormone levels were observed in patients during and after recovery from coronavirus disease 2019 (COVID-19), which raised concerns about negative effects on male fertility. Therefore, this study systematically reviews available data on semen parameters and sex hormones in patients with COVID-19. Methods Systematic search was performed on PubMed and Google Scholar until July 18th, 2022. We identified relevant articles that discussed the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on male fertility. Results A total number of 1,684 articles were identified by using a suitable keyword search strategy. After screening, 26 articles were considered eligible for inclusion in this study. These articles included a total of 1,960 controls and 2,106 patients. When all studies were considered, the results showed that the semen parameters and sex hormone levels of patients infected with SARS-CoV-2 exhibited some significant differences compared with controls. Fortunately, these differences gradually disappear as patients recover from COVID-19. Conclusion While present data show the negative effects of SARS-CoV-2 infection on male fertility, this does not appear to be long-term. Semen quality and hormone levels will gradually increase to normal as patients recover.
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Affiliation(s)
- J Bao
- Jining Medical University, 133, Hehua Road, 272067 Jining, China.
| | - Z Guo
- Jining Medical University, 133, Hehua Road, 272067 Jining, China.
| | - J He
- Jining Medical University, 133, Hehua Road, 272067 Jining, China.
| | - T Leng
- Jining Medical University, 133, Hehua Road, 272067 Jining, China.
| | - Z Wei
- Jining Medical University, 133, Hehua Road, 272067 Jining, China.
| | - C Wang
- Jining Medical University, 133, Hehua Road, 272067 Jining, China.
| | - F Chen
- Jining Medical University, 133, Hehua Road, 272067 Jining, China.
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Xie M, Leng T, Maysami S, Pearson A, Simon R, Xiong ZG, Meller R. Changes in NMDA Receptor Function in Rapid Ischemic Tolerance: A Potential Role for Tri-Heteromeric NMDA Receptors. Biomolecules 2022; 12:biom12091214. [PMID: 36139053 PMCID: PMC9496625 DOI: 10.3390/biom12091214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/19/2022] [Accepted: 08/26/2022] [Indexed: 11/16/2022] Open
Abstract
In this study, we characterize biophysical changes in NMDA receptor function in response to brief non-injurious ischemic stress (ischemic preconditioning). Electrophysiological studies show NMDA receptor function is reduced following preconditioning in cultured rat cortical neurons. This functional change is not due to changes in the reversal potential of the receptor, but an increase in desensitization. We performed concentration-response analysis of NMDA-evoked currents, and demonstrate that preconditioned neurons show a reduced potency of NMDA to evoke currents, an increase in Mg2+ sensitivity, but no change in glycine sensitivity. Antagonists studies show a reduced inhibition of GluN2B antagonists that have an allosteric mode of action (ifenprodil and R-25-6981), but competitive antagonists at the GluR2A and 2B receptor (NVP-AMM077 and conantokin-G) appear to have similar potency to block currents. Biochemical studies show a reduction in membrane surface GluN2B subunits, and an increased co-immunoprecipitation of GluN2A with GluN2B subunits, suggestive of tri-heteromeric receptor formation. Finally, we show that blocking actin remodeling with jasplakinolide, a mechanism of rapid ischemic tolerance, prevents NMDA receptor functional changes and co-immunoprecipitation of GluN2A and 2B subunits. Together, this study shows that alterations in NMDA receptor function following preconditioning ischemia are associated with neuroprotection in rapid ischemic tolerance.
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Affiliation(s)
- Mian Xie
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr SW, Atlanta, GA 30310, USA
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr SW, Atlanta, GA 30310, USA
- Correspondence: (T.L.); (R.M.); Tel.: +1-404-756-6698 (T.L.); +1-404-756-5789 (R.M.)
| | - Samaneh Maysami
- Department of Neuroscience, School of Life Sciences, Keele University, Staffordshire, Keele ST5 5BG, UK
| | - Andrea Pearson
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr SW, Atlanta, GA 30310, USA
| | - Roger Simon
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr SW, Atlanta, GA 30310, USA
| | - Zhi-Gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr SW, Atlanta, GA 30310, USA
| | - Robert Meller
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr SW, Atlanta, GA 30310, USA
- Correspondence: (T.L.); (R.M.); Tel.: +1-404-756-6698 (T.L.); +1-404-756-5789 (R.M.)
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Sheng Y, Wu B, Leng T, Zhu L, Xiong Z. Acid-sensing ion channel 1 (ASIC1) mediates weak acid-induced migration of human malignant glioma cells. Am J Cancer Res 2021; 11:997-1008. [PMID: 33791169 PMCID: PMC7994151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/21/2020] [Indexed: 06/12/2023] Open
Abstract
Glioblastoma is the most aggressive and lethal tumor in the central nervous system in adult and has poor prognosis due to strong proliferation and aggressive invasion capacity. Acidic microenvironment is commonly observed in tumor tissues but the exact role of acidosis in the pathophysiology of glioblastoma and underlying mechanisms remain unclear. Acid-sensing ion channels (ASICs) are proton-gated cation channels activated by low extracellular pH. Recent studies have suggested that ASICs are involved in the pathogenesis of some tumors, such as lung cancer and breast cancer. But the effect of acidosis and activation of ASICs on malignant glioma of the central nervous system has not been reported. In this study, we investigated the expression of ASIC1 in human glioma cell lines (U87MG and A172) and its possible effect on the proliferation and migration of these cells. The results demonstrated that ASIC1 is functionally expressed in U87MG and A172 cells. Treatment with extracellular weak acid (pH 7.0) has no effect on the proliferation but increases the migration of the two cell lines. Application of PcTX1, a specific inhibitor of ASIC1a and ASIC1a/2b channels, or knocking down ASIC1 by siRNA, can abolish the effect of weak acid-induced cell migration. Together, our results indicate that ASIC1 mediates extracellular weak acid induced migration of human malignant glioma cells and may therefore serve as a therapeutic target for malignant glioma in human.
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Affiliation(s)
- Yulan Sheng
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow UniversitySuzhou, China
- Department of Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta, Georgia, USA
| | - Baoming Wu
- Department of Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta, Georgia, USA
| | - Tiandong Leng
- Department of Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta, Georgia, USA
| | - Li Zhu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow UniversitySuzhou, China
| | - Zhigang Xiong
- Department of Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta, Georgia, USA
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Zhou R, Leng T, Yang T, Chen F, Hu W, Xiong ZG. β-Estradiol Protects Against Acidosis-Mediated and Ischemic Neuronal Injury by Promoting ASIC1a (Acid-Sensing Ion Channel 1a) Protein Degradation. Stroke 2019; 50:2902-2911. [PMID: 31412757 PMCID: PMC6756944 DOI: 10.1161/strokeaha.119.025940] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [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] [Indexed: 01/01/2023]
Abstract
Background and Purpose- Sex differences in the incidence and outcome of stroke have been well documented. The severity of stroke in women is, in general, significantly lower than that in men, which is mediated, at least in part, by the protective effects of β-estradiol. However, the detailed mechanisms underlying the neuroprotection by β-estradiol are still elusive. Recent studies have demonstrated that activation of ASIC1a (acid-sensing ion channel 1a) by tissue acidosis, a common feature of brain ischemia, plays an important role in ischemic brain injury. In the present study, we assessed the effects of β-estradiol on acidosis-mediated and ischemic neuronal injury both in vitro and in vivo and explored the involvement of ASIC1a and underlying mechanism. Methods- Cultured neurons and NS20Y cells were subjected to acidosis-mediated injury in vitro. Cell viability and cytotoxicity were measured by methylthiazolyldiphenyl-tetrazolium bromide and lactate dehydrogenase assays, respectively. Transient (60 minutes) focal ischemia in mice was induced by suture occlusion of the middle cerebral artery in vivo. ASIC currents were recorded using whole-cell patch-clamp technique while intracellular Ca2+ concentration was measured with fluorescence imaging using Fura-2. ASIC1a expression was detected by Western blotting and quantitative real-time polymerase chain reaction. Results- Treatment of neuronal cells with β-estradiol decreased acidosis-induced cytotoxicity. ASIC currents and acid-induced elevation of intracellular Ca2+ were all attenuated by β-estradiol treatment. In addition, we showed that β-estradiol treatment reduced ASIC1a protein expression, which was mediated by increased protein degradation, and that estrogen receptor α was involved. Finally, we showed that the level of ASIC1a protein expression in brain tissues and the degree of neuroprotection by ASIC1a blockade were lower in female mice, which could be attenuated by ovariectomy. Conclusions- β-estradiol can protect neurons against acidosis-mediated neurotoxicity and ischemic brain injury by suppressing ASIC1a protein expression and channel function. Visual Overview- An online visual overview is available for this article.
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Affiliation(s)
- Renpeng Zhou
- From the Department of Pharmacology, the Second Hospital of Anhui Medical University, China (R.Z., W.H.)
- Department of Neurobiology, Morehouse School of Medicine, Atlanta (R.Z., T.L., T.Y., Z.X.)
| | - Tiandong Leng
- Department of Neurobiology, Morehouse School of Medicine, Atlanta (R.Z., T.L., T.Y., Z.X.)
| | - Tao Yang
- Department of Neurobiology, Morehouse School of Medicine, Atlanta (R.Z., T.L., T.Y., Z.X.)
| | - Feihu Chen
- Department of Basic and Clinical Pharmacology, School of Pharmacy, Anhui Medical University, China (F.C.)
| | - Wei Hu
- From the Department of Pharmacology, the Second Hospital of Anhui Medical University, China (R.Z., W.H.)
| | - Zhi-Gang Xiong
- Department of Neurobiology, Morehouse School of Medicine, Atlanta (R.Z., T.L., T.Y., Z.X.)
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Leng T, Xiong ZG. Treatment for ischemic stroke: From thrombolysis to thrombectomy and remaining challenges. Brain Circ 2019; 5:8-11. [PMID: 31001594 PMCID: PMC6458775 DOI: 10.4103/bc.bc_36_18] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 02/27/2019] [Accepted: 03/10/2019] [Indexed: 12/28/2022] Open
Abstract
Stroke is a leading cause of death and long-term disabilities. Despite decades of extensive efforts in search of brain injury mechanisms and therapeutic interventions, pharmacological treatment is limited to the use of thrombolytic agent tissue plasminogen activator, which has limited therapeutic time window and potential side effect of intracranial hemorrhage. Over the past few years, endovascular thrombectomy with stent-retriever devices combined with advanced imaging modalities has transformed the standard of stroke care, offering an opportunity to improve the outcome in selected patients as late as 24 h after the onset of stroke. This mini-review summarizes the advancement in the treatment of ischemic stroke, from thrombolysis to thrombectomy and remaining challenges in the field.
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Affiliation(s)
- Tiandong Leng
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, USA
| | - Zhi-Gang Xiong
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, USA
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9
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Liu M, Inoue K, Leng T, Zhou A, Guo S, Xiong ZG. ASIC1 promotes differentiation of neuroblastoma by negatively regulating Notch signaling pathway. Oncotarget 2018; 8:8283-8293. [PMID: 28030818 PMCID: PMC5352400 DOI: 10.18632/oncotarget.14164] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 11/23/2016] [Indexed: 12/25/2022] Open
Abstract
In neurons, up-regulation of Notch activity either inhibits neurite extension or causes retraction of neurites. Conversely, inhibition of Notch1 facilitates neurite extension. Acid-sensing ion channels (ASICs) are a family of proton-gated cation channels, which play critical roles in synaptic plasticity, learning and memory and spine morphogenesis. Our pilot proteomics data from ASIC1a knock out mice implicated that ASIC1a may play a role in regulating Notch signaling, therefore, we explored whether or not ASIC1a regulates neurite growth during neuronal development through Notch signaling. In this study, we determined the effects of ASIC1a on neurite growth in a mouse neuroblastoma cell line, NS20Y cells, by modulating ASIC1a expression. We also determined the relationship between ASIC1a and Notch signaling on neuronal differentiation. Our results showed that down-regulation of ASIC1a in NS20Y cells inhibits CPT-cAMP induced neurite growth, while over expression of ASIC1a promotes its growth. In addition, down-regulation of ASIC1a increased the expression of Notch1 and its target gene Survivin while inhibitor of Notch significantly prevented the neurite extension induced by ASIC1a in NS20Y cells. These data indicate that Notch1 signaling may be required for ASIC1a-mediated neurite growth and neuronal differentiation.
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Affiliation(s)
- Mingli Liu
- Department of Microbiology, Biochemistry & Immunology, Atlanta, GA 30310, USA
| | - Koichi Inoue
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - An Zhou
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Shanchun Guo
- Department of Chemistry, RCMI Cancer Research Center, Xavier University of Louisiana, New Orleans, LA 70125, USA
| | - Zhi-Gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
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Wang Y, Tang L, Yin W, Chen J, Leng T, Zheng X, Zhu W, Zhang H, Qiu P, Yang X, Yan G, Hu H. Simultaneous Determination of Seven Neuroactive Steroids Associated with Depression in Rat Plasma and Brain by High Performance Liquid Chromatography-Tandem Mass Spectrometry. ANAL SCI 2018; 32:981-8. [PMID: 27682404 DOI: 10.2116/analsci.32.981] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Sensitive and specific biomarkers are required for the diagnosis and treatment of depression because the existing diagnostic criteria are subjective and could produce false positives or negatives. Some endogenous neuroactive steroids that have shown either antidepressant effects or concentration changes in individuals with depression could provide potential biomarkers. In this study, a simple and specific method was developed to simultaneously determine seven endogenous neuroactive steroids in biological samples: cortisone, cortisol, dehydroepiandrosterone, estradiol, progesterone, pregnenolone, and testosterone. After liquid-liquid extraction, chromatographic separation was achieved on a C18 column with gradient elution using water-methanol at a flow rate of 300 μL min(-1). Detection and quantitation were performed by tandem mass spectrometry with atmospheric pressure chemical ionization and selected reaction monitoring. Plasma and brain neuroactive steroid levels were then determined in control rats and rats exposed to forced swimming, a classical rodent model of depression. The results showed that the plasma concentrations of testosterone, pregnenolone, and progesterone significantly increased in rats exposed to the forced swimming test. In contrast, brain homogenate levels of cortisol, estradiol, and progesterone decreased, while pregnenolone levels were elevated in this model of depression. In conclusion, a new method to quantify neuroactive steroids was successfully developed and applied to their investigation in rat plasma and brain. The findings of this study indicated that plasma testosterone, pregnenolone, and progesterone levels could provide potential biomarkers for the diagnosis and treatment of depression.
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Affiliation(s)
- Youqiong Wang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University
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11
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Tang L, Yan M, Leng T, Yin W, Cai S, Duan S, Zhu W, Lin S, Huang J, Yan G, Zheng G, Chen Y. Cholestane-3β, 5α, 6β-triol suppresses neuronal hyperexcitability via binding to voltage-gated sodium channels. Biochem Biophys Res Commun 2018; 496:95-100. [DOI: 10.1016/j.bbrc.2018.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 01/01/2018] [Indexed: 12/24/2022]
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12
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Leng T, Lin S, Xiong Z, Lin J. Lidocaine suppresses glioma cell proliferation by inhibiting TRPM7 channels. Int J Physiol Pathophysiol Pharmacol 2017; 9:8-15. [PMID: 28533887 PMCID: PMC5435668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 03/31/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Malignant glioma is the most common brain cancer with devastating prognosis. Recurrence of malignant glioma following surgery is very common with few preventive and therapeutic options. Novel targets and therapeutic agents are constantly sought for better outcome. Our previous study established that inhibition of transient receptor potential melastatin 7 (TRPM7) channels resulted in significant decrease of human glioma cell growth and proliferation. As local anesthetic lidocaine has been shown to inhibit TRPM7 currents, we hypothesize that lidocaine may suppress glioma cell proliferation through TRPM7 channel inhibition. METHODS TRPM7 currents were recorded in rat C6 glioma cells using the whole cell patch clamp technique. Cell growth and proliferation were assessed under microscopic examination and biochemical assays. RESULTS Lidocaine inhibits TRPM7-like currents in a dose-dependent and reversible manner. At 1 and 3 mM, it inhibits ~30% and ~50% of TRPM7 currents. At these concentrations, it is effective in inhibiting the proliferation of C6 cells. As expected, the TRPM7 inhibitors gadolinium and 2-Aminoethoxydiphenyl borate have similar effects on TRPM7 currents and proliferation of C6 cells. Similar to its effect on C6 cells, lidocaine inhibits the proliferation of A172 cells, a human glioblastoma cell line. CONCLUSIONS Lidocaine significantly inhibits the proliferation of glioma cells. The effect of lidocaine is mediated, at least in part, by inhibiting TRPM7 channels.
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Affiliation(s)
- Tiandong Leng
- Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta GA 30329, USA
| | - Suizhen Lin
- Guangzhou Cellproteck Pharmaceutical CO., Ltd3 Lanyue Road, Science City, Guangzhou 510663, PR China
| | - Zhigang Xiong
- Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta GA 30329, USA
| | - Jun Lin
- Department of Anesthesiology, Stony Brook University Health Sciences Center, Stony BrookNY 11794-8480, USA
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13
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Jiang N, Wu J, Leng T, Yang T, Zhou Y, Jiang Q, Wang B, Hu Y, Ji YH, Simon RP, Chu XP, Xiong ZG, Zha XM. Region specific contribution of ASIC2 to acidosis-and ischemia-induced neuronal injury. J Cereb Blood Flow Metab 2017; 37:528-540. [PMID: 26861816 PMCID: PMC5381448 DOI: 10.1177/0271678x16630558] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Acidosis in the brain plays a critical role in neuronal injury in neurological diseases, including brain ischemia. One key mediator of acidosis-induced neuronal injury is the acid-sensing ion channels (ASICs). Current literature has focused on ASIC1a when studying acid signaling. The importance of ASIC2, which is also widely expressed in the brain, has not been appreciated. We found here a region-specific effect of ASIC2 on acid-mediated responses. Deleting ASIC2 reduced acid-activated current in cortical and striatal neurons, but had no significant effect in cerebellar granule neurons. In addition, we demonstrated that ASIC2 was important for ASIC1a expression, and that ASIC2a but not 2b facilitated ASIC1a surface trafficking in the brain. Further, we showed that ASIC2 deletion attenuated acidosis/ischemia-induced neuronal injury in organotypic hippocampal slices but had no effect in organotypic cerebellar slices. Consistent with an injurious role of ASIC2, we showed that ASIC2 deletion significantly protected the mouse brain from ischemic damage in vivo. These data suggest a critical region-specific contribution of ASIC2 to neuronal injury and reveal an important functional difference between ASIC2a and 2b in the brain.
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Affiliation(s)
- Nan Jiang
- 1 Department of Physiology and Cell Biology, University of South Alabama, Mobile, USA.,2 School of Life Sciences, Shanghai University, Shanghai, China
| | - Junjun Wu
- 1 Department of Physiology and Cell Biology, University of South Alabama, Mobile, USA.,3 China State Institute of Pharmaceutical Industry, Shanghai, China
| | - Tiandong Leng
- 4 Department of Neurobiology, Morehouse School of Medicine, Atlanta, USA
| | - Tao Yang
- 4 Department of Neurobiology, Morehouse School of Medicine, Atlanta, USA
| | - Yufan Zhou
- 1 Department of Physiology and Cell Biology, University of South Alabama, Mobile, USA
| | - Qian Jiang
- 5 Department of Basic Medical Science, University of Missouri-Kansas City, Kansas City, USA
| | - Bin Wang
- 6 Department of Mathematics and Statistics, University of South Alabama, Mobile, USA
| | - Youjia Hu
- 3 China State Institute of Pharmaceutical Industry, Shanghai, China
| | - Yong-Hua Ji
- 2 School of Life Sciences, Shanghai University, Shanghai, China
| | - Roger P Simon
- 4 Department of Neurobiology, Morehouse School of Medicine, Atlanta, USA
| | - Xiang-Ping Chu
- 5 Department of Basic Medical Science, University of Missouri-Kansas City, Kansas City, USA
| | - Zhi-Gang Xiong
- 4 Department of Neurobiology, Morehouse School of Medicine, Atlanta, USA
| | - Xiang-Ming Zha
- 1 Department of Physiology and Cell Biology, University of South Alabama, Mobile, USA
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14
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Yan M, Leng T, Tang L, Zheng X, Lu B, Li Y, Sheng L, Lin S, Shi H, Yan G, Yin W. Neuroprotectant androst-3β, 5α, 6β-triol suppresses TNF-α-induced endothelial adhesion molecules expression and neutrophil adhesion to endothelial cells by attenuation of CYLD-NF-κB pathway. Biochem Biophys Res Commun 2017; 483:892-896. [PMID: 28082198 DOI: 10.1016/j.bbrc.2017.01.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [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: 12/28/2016] [Accepted: 01/08/2017] [Indexed: 10/20/2022]
Abstract
Neuroinflammation is one of key pathologic element in neurological diseases including stroke, traumatic brain injury, Alzheimer' s Disease, Parkinson's Disease, and multiple sclerosis as well. Up-regulation of endothelial adhesion molecules, which facilitate leukocyte adhesion to the endothelium, is the vital process of endothelial cells mediated neuroinflammation. Androst-3β, 5α, 6β-triol (Triol) is a synthetic steroid which has been reported to have neuroprotective effects in hypoxia/re-oxygenation-induced neuronal injury model. In the present study, we firstly investigated whether Triol inhibited the TNF-α-induced inflammatory response in rat brain microvascular endothelial cells (RBMECs). Our data showed that Triol decreased TNF-α-induced expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) and the adhesion of neutrophil to RBMECs. We also found that Triol inhibited TNF-α-induced degradation of IκBα and phosphorylation of NF-κBp65 that are required for NF-κB activation. Furthermore, Triol significantly reversed TNF-α-induced down-expression of CYLD, which is a deubiquitinase that negatively regulates activation of NF-κB. These results suggest that Triol displays an anti-inflammatory effect on TNF-α-induced RBMECs via downregulating of CYLD-NF-κB signaling pathways and might have a potential benefit in therapeutic neuroinflammation related diseases.
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Affiliation(s)
- Min Yan
- Department of Pathology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, GD 510080, PR China
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Lipeng Tang
- Department of Pharmacology of Traditional Chinese Medicine, Guangdong Province's Traditional Chinese Medical Hospital, Guangzhou, GD 510120, PR China
| | - Xiaoke Zheng
- Department of Pathology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, GD 510080, PR China
| | - Bingzheng Lu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, GD 510080, PR China
| | - Yuan Li
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, GD 510080, PR China
| | - Longxiang Sheng
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, GD 510080, PR China
| | - Suizhen Lin
- Guangzhou Cellprotek Pharmaceutical, G Building F/4, 3 Lanyue Road, Science City, Guangzhou, 510663, PR China
| | - Haitao Shi
- Guangzhou Cellprotek Pharmaceutical, G Building F/4, 3 Lanyue Road, Science City, Guangzhou, 510663, PR China
| | - Guangmei Yan
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, GD 510080, PR China
| | - Wei Yin
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, GD 510080, PR China.
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15
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Chen J, Dou Y, Zheng X, Leng T, Lu X, Ouyang Y, Sun H, Xing F, Mai J, Gu J, Lu B, Yan G, Lin J, Zhu W. TRPM7 channel inhibition mediates midazolam-induced proliferation loss in human malignant glioma. Tumour Biol 2016; 37:14721-14731. [PMID: 27629139 DOI: 10.1007/s13277-016-5317-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [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: 05/10/2016] [Accepted: 09/05/2016] [Indexed: 01/09/2023] Open
Abstract
The melastatin-like transient receptor potential 7 (TRPM7) has been implicated in proliferation or apoptosis of some cancers, indicating the potential of TRPM7 as an anti-anaplastic target. Here, we identified the characteristic TRPM7 channel currents in human malignant glioma MGR2 cells, which could be blocked by a pharmacologic inhibitor Gd3+. We mined the clinical sample data from Oncomine Database and found that human malignant glioma tissues expressed higher TRPM7 mRNA than normal brain ones. Importantly, we identified a widely used clinical anesthetic midazolam as a TRPM7 inhibitor. Midazolam treatment for seconds suppressed the TRPM7 currents and calcium influx, and treatment for 48 h inhibited the TRPM7 expression. The inhibitory effect on TRPM7 accounts for the proliferation loss and G0/G1 phase cell cycle arrest induced by midazolam. Our data demonstrates that midazolam represses proliferation of human malignant glioma cells through inhibiting TRPM7 currents, which may be further potentiated by suppressing the expression of TRPM7. Our result indicates midazolam as a pharmacologic lead compound with brain-blood barrier permeability for targeting TRPM7 in the glioma.
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Affiliation(s)
- Jingkao Chen
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China.,School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, People's Republic of China
| | - Yunling Dou
- Department of Anesthesiology, Department of Pathology and Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510080, People's Republic of China
| | - Xiaoke Zheng
- Department of Anesthesiology, Department of Pathology and Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510080, People's Republic of China
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, 30329, USA
| | - Xiaofang Lu
- Department of Anesthesiology, Department of Pathology and Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510080, People's Republic of China
| | - Ying Ouyang
- Department of Pediatrics, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, People's Republic of China
| | - Huawei Sun
- Department of Anesthesiology, Department of Pathology and Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510080, People's Republic of China
| | - Fan Xing
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Jialuo Mai
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Jiayu Gu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Bingzheng Lu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Guangmei Yan
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China.,South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | - Jun Lin
- Department of Anesthesiology, Stony Brook University Health Science Center, Stony Brook, NY, 11794-8480, USA.
| | - Wenbo Zhu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China. .,South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China.
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16
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O'Bryant Z, Leng T, Liu M, Inoue K, Vann KT, Xiong ZG. Acid Sensing Ion Channels (ASICs) in NS20Y cells - potential role in neuronal differentiation. Mol Brain 2016; 9:68. [PMID: 27342076 PMCID: PMC4920985 DOI: 10.1186/s13041-016-0249-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 06/15/2016] [Indexed: 11/10/2022] Open
Abstract
Cultured neuronal cell lines can express properties of mature neurons if properly differentiated. Although the precise mechanisms underlying neuronal differentiation are not fully understood, the expression and activation of ion channels, particularly those of Ca2+-permeable channels, have been suggested to play a role. In this study, we explored the presence and characterized the properties of acid-sensing ion channels (ASICs) in NS20Y cells, a neuronal cell line previously used for the study of neuronal differentiation. In addition, the potential role of ASICs in cell differentiation was explored. Reverse Transcription Polymerase Chain Reaction and Western blot revealed the presence of ASIC1 subunits in these cells. Fast drops of extracellular pH activated transient inward currents which were blocked, in a dose dependent manner, by amiloride, a non-selective ASIC blocker, and by Psalmotoxin-1 (PcTX1), a specific inhibitor for homomeric ASIC1a and heteromeric ASIC1a/2b channels. Incubation of cells with PcTX1 significantly reduced the differentiation of NS20Y cells induced by cpt-cAMP, as evidenced by decreased neurite length, dendritic complexity, decreased expression of functional voltage gated Na+ channels. Consistent with ASIC1a inhibition, ASIC1a knockdown with small interference RNA significantly attenuates cpt-cAMP-induced increase of neurite outgrowth. In summary, we described the presence of functional ASICs in NS20Y cells and demonstrate that ASIC1a plays a role in the differentiation of these cells.
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Affiliation(s)
- Zaven O'Bryant
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1945, USA
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1945, USA
| | - Mingli Liu
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1945, USA
| | - Koichi Inoue
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1945, USA
| | - Kiara T Vann
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1945, USA
| | - Zhi-Gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1945, USA.
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17
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Inoue K, Leng T, Yang T, Zeng Z, Ueki T, Xiong ZG. Role of serum- and glucocorticoid-inducible kinases in stroke. J Neurochem 2016; 138:354-61. [PMID: 27123541 DOI: 10.1111/jnc.13650] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [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: 12/01/2015] [Revised: 04/02/2016] [Accepted: 04/22/2016] [Indexed: 01/03/2023]
Abstract
Increased expression of serum- and glucocorticoid-inducible kinase 1 (SGK1) can be induced by stress and growth factors in mammals, and plays an important role in cancer, diabetes, and hypertension. A recent work suggested that SGK1 activity restores damage in a stroke model. To further investigate the role of SGKs in ischemic brain injury, we examined how SGK inhibitors influence stroke outcome in vivo and neurotoxicity in vitro. Infarct volumes were compared in adult mice with middle cerebral artery occlusion, followed by 24 h reperfusion, in the absence or presence of SGK inhibitors. Neurotoxicity assay, electrophysiological recording, and fluorescence Ca(2+) imaging were carried out using cultured cortical neurons to evaluate the underlying mechanisms. Contrary to our expectation, infarct volume by stroke decreased significantly when SGK inhibitor, gsk650394, or EMD638683, was administrated 30 min before middle cerebral artery occlusion under normal and diabetic conditions. SGK inhibitors reduced neurotoxicity mediated by N-methyl-D-aspartate (NMDA) receptors, a leading factor responsible for cell death in stroke. SGK inhibitors also ameliorated Ca(2+) increase and peak amplitude of NMDA current in cultured neurons. In addition, SGK inhibitor gsk650394 decreased phosphorylation of Nedd4-2 and inhibited voltage-gated sodium currents. These observations suggest that SGK activity exacerbates stroke damage and that SGK inhibitors may be useful candidates for therapeutic intervention. To investigate the role of serum- and glucocorticoid-inducible kinases (SGKs) in ischemic brain injury, we examined how SGK inhibitors influence stroke outcome. Infarct volumes induced by middle cerebral artery occlusion were decreased significantly by SGK inhibitors. The inhibitors also reduced glutamate toxicity, at least partly, by attenuation of NMDA and voltage-gated sodium currents. Thus, SGK inhibition attenuates stroke damage.
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Affiliation(s)
- Koichi Inoue
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, USA.,Department of Integrative Anatomy, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, USA
| | - Tao Yang
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, USA
| | - Zhao Zeng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, USA
| | - Takatoshi Ueki
- Department of Integrative Anatomy, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Zhi-Gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, USA
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18
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Leng T, Gao X, Dilger JP, Lin J. Neuroprotective effect of lidocaine: is there clinical potential? Int J Physiol Pathophysiol Pharmacol 2016; 8:9-13. [PMID: 27186318 PMCID: PMC4859874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 04/10/2016] [Indexed: 06/05/2023]
Abstract
Local anesthetic lidocaine has been shown to be protective in animal models of focal and global ischemia as well as in in vitro hypoxic models. Lidocaine has been tested in patients for its potential protective effect on postoperative cognitive dysfunction. This mini-review summarizes the laboratory and clinical evidences and discusses its clinical applications as neuroprotective agent.
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Affiliation(s)
- Tiandong Leng
- Neuroscience Institute, Morehouse School of MedicineAtlanta, GA 30310, USA
| | - Xiuren Gao
- Department of Cardiology, First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou, Guangdong 510080, P.R. China
| | - James P Dilger
- Department of Anesthesiology, Stony Brook University Health Sciences Center, Stony BrookNY 11794-8480, USA
| | - Jun Lin
- Department of Anesthesiology, Stony Brook University Health Sciences Center, Stony BrookNY 11794-8480, USA
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19
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Yan M, Zhu W, Zheng X, Li Y, Tang L, Lu B, Chen W, Qiu P, Leng T, Lin S, Yan G, Yin W. Effect of glutamate on lysosomal membrane permeabilization in primary cultured cortical neurons. Mol Med Rep 2016; 13:2499-505. [PMID: 26821268 PMCID: PMC4768955 DOI: 10.3892/mmr.2016.4819] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [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] [Received: 02/11/2015] [Accepted: 12/08/2015] [Indexed: 11/20/2022] Open
Abstract
Glutamate is the principal neurotransmitter in the central nervous system. Glutamate-mediated excitotoxicity is the predominant cause of cerebral damage. Recent studies have shown that lysosomal membrane permeabilization (LMP) is involved in ischemia-associated neuronal death in non-human primates. This study was designed to investigate the effect of glutamate on lysosomal stability in primary cultured cortical neurons. Glutamate treatment for 30 min induced the permeabilization of lysosomal membranes as assessed by acridine orange redistribution and immunofluorescence of cathepsin B in the cytoplasm. Inhibition of glutamate excitotoxicity by the NMDA receptor antagonist MK-801 and the calcium chelator ethylene glycolbis (2-aminoethylether)-N, N, N′, N′-tetraacetic acid, rescued lysosomes from permeabilization. The role of calpain and reactive oxygen species (ROS) in inducing LMP was also investigated. Ca2+ overload following glutamate treatment induced the activation of calpain and the production of ROS, which are two major contributors to neuronal death. It has been reported that lysosomal-associated membrane protein 2 (LAMP2) and heat shock protein (HSP)70 are two calpain substrates that promote LMP in cancer cells; however, it was found that calpains were activated by glutamate, but only LAMP2 was subsequently degraded. Furthermore, LMP was not alleviated by treatment with the calpain inhibitors calpeptin and SJA6017, which blocked the cleavage of the calpain substrate α-fodrin. It was demonstrated that LMP was significantly alleviated by treatment with the antioxidant N-Acetyl-L-cysteine, indicating that LMP involvement in early glutamate excitotoxicity may be mediated partly by ROS rather than calpain activation. Overall, these data shed light on the role of ROS-mediated LMP in early glutamate excitotoxicity.
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Affiliation(s)
- Min Yan
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Wenbo Zhu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Xiaoke Zheng
- Department of Pathology, The First Affiliated Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510089, P.R. China
| | - Yuan Li
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Lipeng Tang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Bingzheng Lu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Wenli Chen
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Pengxin Qiu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Tiandong Leng
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Suizhen Lin
- Guangzhou Cellprotek Pharmaceutical Co., Ltd., Guangzhou, Guangdong 510663, P.R. China
| | - Guangmei Yan
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Wei Yin
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
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20
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Wu J, Leng T, Jing L, Jiang N, Chen D, Hu Y, Xiong ZG, Zha XM. Two di-leucine motifs regulate trafficking and function of mouse ASIC2a. Mol Brain 2016; 9:9. [PMID: 26819004 PMCID: PMC4729175 DOI: 10.1186/s13041-016-0190-x] [Citation(s) in RCA: 11] [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] [Received: 12/03/2015] [Accepted: 01/21/2016] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Acid-sensing ion channels (ASICs) are proton-gated cation channels that mediate acid-induced responses in neurons. ASICs are important for mechanosensation, learning and memory, fear, pain, and neuronal injury. ASIC2a is widely expressed in the nervous system and modulates ASIC channel trafficking and activity in both central and peripheral systems. Here, to better understand mechanisms regulating ASIC2a, we searched for potential protein motifs that regulate ASIC2a trafficking. RESULTS AND CONCLUSIONS We identified a LLDLL sequence in the C-terminal juxtamembrane region of ASIC2a. Deleting or mutating the LLDLL sequence increased total expression and surface levels of ASIC2a in CHO cells. Mutating either of the two LL motifs had a similar effect. We further assessed ASIC2a localization in organotypic hippocampal slice neurons. The LL motif mutants exhibited increased dendritic trafficking and elevated targeting to dendritic spines. Consistent with an efficient trafficking, the LL motif mutants increased acid-activated current density. In addition, mutating the second LL motif increased pH sensitivity of the channel. These data identify the LL motifs as a negative regulator of ASIC2a trafficking and function, and suggest novel regulatory mechanisms in acid signaling.
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Affiliation(s)
- Junjun Wu
- Department of Physiology and Cell Biology, University of South Alabama College of Medicine, 5851 USA Dr N, MSB3074, Mobile, AL, 36688, USA. .,China State Institute of Pharmaceutical Industry, 285 Gebaini Road, Shanghai, 201203, China.
| | - Tiandong Leng
- Department of Neurobiology, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, 30310, GA, USA.
| | - Lan Jing
- Department of Physiology and Cell Biology, University of South Alabama College of Medicine, 5851 USA Dr N, MSB3074, Mobile, AL, 36688, USA. .,State Key Lab of New Drug & Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Rd, Shanghai, 200040, China.
| | - Nan Jiang
- Department of Physiology and Cell Biology, University of South Alabama College of Medicine, 5851 USA Dr N, MSB3074, Mobile, AL, 36688, USA. .,Shanghai University School of Life Sciences, Shanghai, China.
| | - Daijie Chen
- China State Institute of Pharmaceutical Industry, 285 Gebaini Road, Shanghai, 201203, China.
| | - Youjia Hu
- China State Institute of Pharmaceutical Industry, 285 Gebaini Road, Shanghai, 201203, China.
| | - Zhi-Gang Xiong
- Department of Neurobiology, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, 30310, GA, USA.
| | - Xiang-ming Zha
- Department of Physiology and Cell Biology, University of South Alabama College of Medicine, 5851 USA Dr N, MSB3074, Mobile, AL, 36688, USA.
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Leng T, Liu A, Wang Y, Chen X, Zhou S, Li Q, Zhu W, Zhou Y, Su X, Huang Y, Yin W, Qiu P, Hu H, Xiong ZG, Zhang J, Yan G. Naturally occurring marine steroid 24-methylenecholestane-3β,5α,6β,19-tetraol functions as a novel neuroprotectant. Steroids 2016; 105:96-105. [PMID: 26631550 DOI: 10.1016/j.steroids.2015.11.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Revised: 11/02/2015] [Accepted: 11/19/2015] [Indexed: 12/13/2022]
Abstract
Steroids have been shown to have multiple effects on the nervous system including neuroprotective activities, and they have the potential to be used for the treatment of neurodegenerative diseases. In this current study, we tested the hypothesis that the marine steroid 24-methylenecholestane-3β,5α,6β,19-tetraol (Tetrol) has a neuroprotective effect. (1) We synthesized Tetrol through a multiple step reaction starting from hyodeoxycholic acid (HDCA). (2) We then evaluated the neuroprotective effect of Tetrol with a glutamate-induced neuronal injury model in vitro. Tetrol concentration dependently increased the survival rate of cerebellar granule neurons challenged with toxic concentration of glutamate. Consistently, Tetrol significantly decreased glutamate-induced lactate dehydrogenase (LDH) release with a threshold concentration of 2.5 μM. (3) We further evaluated the neuroprotective effect of Tetrol in a middle cerebral artery occlusion (MCAO)-induced cerebral ischemia model in rat. Tetrol, at a dose of 12 mg/kg, significantly decreased MCAO-induced infarction volume by ∼50%. (4) Finally, we probed the mechanism and found that Tetrol concentration dependently attenuated N-methyl-d-aspartate (NMDA)-induced intracellular calcium ([Ca(2+)]i) increase with an IC50 of 7.8±0.62 μM, and inhibited NMDA currents in cortical neurons with an IC50 of 10.28±0.71 μM. Taken together, we have synthesized and characterized Tetrol as a novel neuroprotectant through negative modulation of NMDA receptors.
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Affiliation(s)
- Tiandong Leng
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China; Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr SW, Atlanta, GA 30329, USA
| | - Ailing Liu
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Youqiong Wang
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Xinying Chen
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, GD 510006, China
| | - Shujia Zhou
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, GD 510006, China
| | - Qun Li
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Wenbo Zhu
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Yuehan Zhou
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Xingwen Su
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Yijun Huang
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Wei Yin
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Pengxin Qiu
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China
| | - Haiyan Hu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, GD 510006, China
| | - Zhi-gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr SW, Atlanta, GA 30329, USA
| | - Jingxia Zhang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, GD 510006, China.
| | - Guangmei Yan
- Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, GD 510080, China.
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22
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Tang L, Wang Y, Leng T, Sun H, Zhou Y, Zhu W, Qiu P, Zhang J, Lu B, Yan M, Chen W, Su X, Yin W, Huang Y, Hu H, Yan G. Cholesterol metabolite cholestane-3β,5α,6β-triol suppresses epileptic seizures by negative modulation of voltage-gated sodium channels. Steroids 2015; 98:166-72. [PMID: 25578735 DOI: 10.1016/j.steroids.2014.12.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 12/27/2014] [Accepted: 12/29/2014] [Indexed: 11/24/2022]
Abstract
Imbalance of excitation and inhibition in neurons is implicated in the pathogenesis of epilepsy. Voltage-gated sodium channels, which play a vital role in regulating neuronal excitability, are one of the major targets for developing anti-epileptic drugs. Here we provide evidence that cholestane-3β,5α,6β-triol (triol), a major metabolic oxysterol of cholesterol, is an effective state-dependent negative sodium channels modulator. Triol reduced Na(+) current density in a concentration-dependent manner. 10 μM triol shifted steady-state/fast/slow inactivation curves of sodium channels toward the hyperpolarizing direction. Additionally, triol reduced voltage-gated sodium currents in a voltage- and frequency-dependent manner. In a kainic acid-induced seizures mouse model, triol (25 mg/kg) significantly increased the latency of seizure onset and attenuated seizure severity. Our findings provide novel insights for understanding the modulatory role of a small molecular oxysterol on voltage-gated sodium channels and suggest triol may represent a novel and promising candidate for epilepsy intervention.
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Affiliation(s)
- Lipeng Tang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Youqiong Wang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Tiandong Leng
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Huanhuan Sun
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Yuehan Zhou
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China; Department of Pharmacology, Guilin Medical University, Guilin, GX 541004, China
| | - Wenbo Zhu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Pengxin Qiu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Jingxia Zhang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, GD 510006, China
| | - Bingzheng Lu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Min Yan
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Wenli Chen
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Xinwen Su
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Wei Yin
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Yijun Huang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China
| | - Haiyan Hu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, GD 510006, China.
| | - Guangmei Yan
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, GD 510080, China.
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Zeng Z, Leng T, Feng X, Sun H, Inoue K, Zhu L, Xiong ZG. Silencing TRPM7 in mouse cortical astrocytes impairs cell proliferation and migration via ERK and JNK signaling pathways. PLoS One 2015; 10:e0119912. [PMID: 25799367 PMCID: PMC4370640 DOI: 10.1371/journal.pone.0119912] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 01/17/2015] [Indexed: 11/18/2022] Open
Abstract
Transient receptor potential melastatin 7 (TRPM7), a non-selective cation channel, is highly expressed expressed in the brain and plays a critical role in ischemic neuronal death. Astrocyte, the most abundant cell type in central nervous system (CNS), exerts many essential functions in the physiological and pathological conditions. Here we investigated the expression and functions of the TRPM7 channel in mouse cortical astrocytes. Using reverse transcription (RT)-PCR, immunostaining, western blot and patch clamp recording, we showed that functional TRPM7 channel is expressed in cultured mouse cortical astrocytes. Knocking down TRPM7 with specific siRNA impairs the proliferation and migration of astrocytes by 40.2% ± 3.9% and 40.1% ± 11.5%, respectively. Consistently, inhibition of TRPM7 with 2-aminoethoxydiphenyl borate (2-APB) also decreases astrocyte proliferation and migration by 46.1% ± 2.5% and 64.2% ± 2.4%. MAPKs and Akt signaling pathways have been shown to be implicated in TRPM7-mediated responses including cell proliferation and migration. Our data show that suppression of TRPM7 in astrocytes reduces the phosphorylation of extracellular signal-regulated kinases (ERK) and c-Jun N-terminal kinases (JNK), but not p38 mitogen-activated protein kinase and Akt. In addition, TRPM7, as a cation channel, has been involved in the Ca²⁺ and Mg²⁺ homeostasis in several types of cells. In our study, we found that silencing TRPM7 decreases the intracellular basal Mg²⁺ concentration without affecting Ca²⁺ concentration in astrocytes. However, an addition of Mg²⁺ to the growth medium could not rescue the impaired proliferation of astrocytes. Together, our data suggest that TRPM7 channel may play a critical role in the proliferation and migration of astrocytes via the ERK and JNK pathways.
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Affiliation(s)
- Zhao Zeng
- Cyrus Tang Hematology center, Collaborative Innovation Center of Hematology, MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Key Lab of Preventive and translational Medicine for Geriatric Diseases, Soochow University, Suzhou, Jiangsu, China
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, United States of America
| | - Xuechao Feng
- Membrane Channel Research Laboratory and Key Laboratory for Applied Statistics of MOE, Northeast Normal University, Changchun, P.R. China
| | - Huawei Sun
- Department of Cardiology, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Koichi Inoue
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, United States of America
| | - Li Zhu
- Cyrus Tang Hematology center, Collaborative Innovation Center of Hematology, MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Key Lab of Preventive and translational Medicine for Geriatric Diseases, Soochow University, Suzhou, Jiangsu, China
- * E-mail: ; (LZ); (ZGX)
| | - Zhi-Gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, United States of America
- * E-mail: ; (LZ); (ZGX)
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Abstract
Transient receptor potential melastatin 7 (TRPM7) is a nonselective cation channel with an α-kinase domain in its COOH terminal, known to play a role in diverse physiological and pathological processes such as Mg2+ homeostasis, cell proliferation, and hypoxic neuronal injury. Increasing evidence suggests that TRPM7 contributes to the physiology/pathology of vascular systems. For example, we recently demonstrated that silencing TRPM7 promotes growth and proliferation and protects against hyperglycemia-induced injury in human umbilical vein endothelial cells (HUVECs). Here we investigated the potential effects of TRPM7 on morphology, adhesion, migration, and tube formation of vascular endothelial cells and the potential underlying mechanism. We showed that inhibition of TRPM7 function in HUVECs by silencing TRPM7 decreases the density of TRPM7-like current and cell surface area and inhibits cell adhesion to Matrigel. Silencing TRPM7 also promotes cell migration, wound healing, and tube formation. Further studies showed that the extracellular signal-regulated kinase (ERK) pathway is involved in the change of cell morphology and the increase in HUVEC migration induced by TRPM7 silencing. We also demonstrated that silencing TRPM7 enhances the phosphorylation of myosin light chain (MLC) in HUVECs, which might be involved in the enhancement of cell contractility and motility. Collectively, our data suggest that the TRPM7 channel negatively regulates the function of vascular endothelial cells. Further studies on the underlying mechanism may facilitate the development of the TRPM7 channel as a target for the therapeutic intervention of vascular diseases.
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Affiliation(s)
- Zhao Zeng
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Ministry of Health Key Laboratory of Thrombosis and Hemostasis, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, China; and Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia
| | - Koichi Inoue
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia
| | - Huawei Sun
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia
| | - Xuechao Feng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia
| | - Li Zhu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Ministry of Health Key Laboratory of Thrombosis and Hemostasis, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, China; and
| | - Zhi-Gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia
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Hu H, Zhou Y, Leng T, Liu A, Wang Y, You X, Chen J, Tang L, Chen W, Qiu P, Yin W, Huang Y, Zhang J, Wang L, Sang H, Yan G. The major cholesterol metabolite cholestane-3β,5α,6β-triol functions as an endogenous neuroprotectant. J Neurosci 2014; 34:11426-38. [PMID: 25143622 PMCID: PMC6615515 DOI: 10.1523/jneurosci.0344-14.2014] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Revised: 06/10/2014] [Accepted: 06/25/2014] [Indexed: 12/11/2022] Open
Abstract
Overstimulation of NMDA-type glutamate receptors is believed to be responsible for neuronal death of the CNS in various disorders, including cerebral and spinal cord ischemia. However, the intrinsic and physiological mechanisms of modulation of these receptors are essentially unknown. Here we report that cholestane-3β,5α,6β-triol (triol), a major metabolite of cholesterol, is an endogenous neuroprotectant and protects against neuronal injury both in vitro and in vivo via negative modulation of NMDA receptors. Treatment of cultured neurons with triol protects against glutamate-induced neurotoxicity, and administration of triol significantly decreases neuronal injury after spinal cord ischemia in rabbits and transient focal cerebral ischemia in rats. An inducible elevation of triol is associated with ischemic preconditioning and subsequent neuroprotection in the spinal cord of rabbits. This neuroprotection is effectively abolished by preadministration of a specific inhibitor of triol synthesis. Physiological concentrations of triol attenuate [Ca(2+)]i induced by glutamate and decrease inward NMDA-mediated currents in cultured cortical neurons and HEK-293 cells transiently transfected with NR1/NR2B NMDA receptors. Saturable binding of [(3)H]triol to cerebellar granule neurons and displacement of [(3)H]MK-801 binding to NMDA receptors by triol suggest that direct blockade of NMDA receptors may underlie the neuroprotective properties. Our findings suggest that the naturally occurring oxysterol, the major cholesterol metabolite triol, functions as an endogenous neuroprotectant in vivo, which may provide novel insights into understanding and developing potential therapeutics for disorders in the CNS.
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Affiliation(s)
- Haiyan Hu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China
| | | | | | | | | | - Xiuhua You
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China
| | | | | | | | | | - Wei Yin
- Biochemistry, Zhongshan School of Medicine and
| | | | | | - Liwei Wang
- Department of Physiology, School of Medicine, Ji-nan University, Guangzhou, Guangdong 510632, China, and
| | - Hanfei Sang
- Departments of Pharmacology and Department of Anesthesiology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
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Sun H, Leng T, Zeng Z, Gao X, Inoue K, Xiong ZG. Role of TRPM7 channels in hyperglycemia-mediated injury of vascular endothelial cells. PLoS One 2013; 8:e79540. [PMID: 24223965 PMCID: PMC3815131 DOI: 10.1371/journal.pone.0079540] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 09/22/2013] [Indexed: 12/29/2022] Open
Abstract
This study investigated the change of transient receptor potential melastatin 7 (TRPM7) expression by high glucose and its role in hyperglycemia induced injury of vascular endothelial cells. Human umbilical vein endothelial cells (HUVECs) were incubated in the presence or absence of high concentrations of D-glucose (HG) for 72h. RT-PCR, Real-time PCR, Western blotting, Immunofluorescence staining and whole-cell patch-clamp recordings showed that TRPM7 mRNA, TRPM7 protein expression and TRPM7-like currents were increased in HUVECs following exposure to HG. In contrast to D-glucose, exposure of HUVECs to high concentrations of L-glucose had no effect. HG increased reactive oxygen species (ROS) generation, cytotoxicity and decreased endothelial nitric oxide synthase protein expression, which could be attenuated by knockdown of TRPM7 with TRPM7 siRNA. The protective effect of silencing TRPM7 against HG induced endothelial injury was abolished by U0126, an inhibitor of the extracellular signal-regulated kinase signaling pathway. These observations suggest that TRPM7 channels play an important role in hyperglycemia-induced injury of vascular endothelial cells.
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Affiliation(s)
- Huawei Sun
- Department of Cardiology, First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, United States of America
| | - Tiandong Leng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, United States of America
| | - Zhao Zeng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, United States of America
| | - Xiuren Gao
- Department of Cardiology, First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- * E-mail: (XG); (ZGX)
| | - Koichi Inoue
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, United States of America
| | - Zhi-Gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, United States of America
- * E-mail: (XG); (ZGX)
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Ou Y, Zheng X, Gao Y, Shu M, Leng T, Li Y, Yin W, Zhu W, Huang Y, Zhou Y, Tang J, Qiu P, Yan G, Hu J, Ruan H, Hu H. Activation of cyclic AMP/PKA pathway inhibits bladder cancer cell invasion by targeting MAP4-dependent microtubule dynamics. Urol Oncol 2013; 32:47.e21-8. [PMID: 24140250 DOI: 10.1016/j.urolonc.2013.06.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 06/27/2013] [Accepted: 06/27/2013] [Indexed: 10/26/2022]
Abstract
OBJECTIVE With the notorious reputation of the vicious invasion, the bladder cancer is the most common malignant tumor of the urinary system. Inhibiting invasion through microtubule dynamics interruption has emerged as an important treatment of bladder cancer. Here we investigated the role of the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) pathway in human bladder cancer cells invasion. MATERIALS AND METHODS With or without the treatment of various cAMP elevators, we assessed invasive and migrated capabilities of T24 and UM-UC-3, two high-grade invasive bladder cancer cell lines, using matrigel transwell inserts assay and scratch wound healing assay. The microtubule (MT) dynamics were examined by immunofluorescence and immunoblotting. Microtubule-Associated Protein 4 (MAP4) was silenced to investigate its role in tumor invasion. We also analyzed gene expression of MAP4 in 34 patients with bladder cancer using immunohistochemical staining assay. The interaction between PKA and MAP4 was examined by co-immunoprecipitation. RESULTS We used cAMP elevators and small interfering RNA of MAP4 here, found that both of them can potently inhibit the invasion and the migration of bladder cancer cells by disrupting microtubule (MT) cytoskeleton. Consistently, the bladder cancer grade is positively correlated with the protein level of MAP4. Furthermore, we found that cAMP/PKA signaling can disrupt MT cytoskeleton by the phosphorylation of MAP4. CONCLUSION Our results indicated that the cAMP/PKA signaling pathway might inhibit bladder cancer cell invasion by targeting MAP4-dependent microtubule dynamics, which could be exploited for the therapy of invasive bladder cancer.
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Affiliation(s)
- Yanqiu Ou
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China; Guangdong Provincial Cardiovascular Institute, Guangdong General Hospital, Guangdong Provincial Academy of Medical Sciences, Guangzhou, P.R. China
| | - Xiaoke Zheng
- Department of Phathology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, P.R. China; Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Yixing Gao
- Department of Neurobiology, College of Basic Medical Science, The Third Military Medical University, Chongqing, P.R. China
| | - Minfeng Shu
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Tiandong Leng
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Yan Li
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Wei Yin
- Department of Biochemistry, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Wenbo Zhu
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Yijun Huang
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Yuxi Zhou
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Jianjun Tang
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Pengxin Qiu
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Guangmei Yan
- Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Jun Hu
- Department of Microbiology, Zhong-shan School of Medcine, Sun Yat-Sen University, Guangzhou, P.R. China; Department of Pharmacology, Zhong-shan Medical College, Sun Yat-Sen University, Guangzhou, P.R. China.
| | - Huaizhen Ruan
- Department of Neurobiology, College of Basic Medical Science, The Third Military Medical University, Chongqing, P.R. China.
| | - Haiyan Hu
- Department of Pharmaceutics, School of Pharmaceutical Science, Sun Yat-Sen University, Guangzhou, P.R. China.
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Sun H, Zheng X, Zhou Y, Zhu W, Ou Y, Shu M, Gao X, Leng T, Qiu P, Yan G. Alphaxalone inhibits growth, migration and invasion of rat C6 malignant glioma cells. Steroids 2013; 78:1041-5. [PMID: 23831782 DOI: 10.1016/j.steroids.2013.06.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 06/05/2013] [Accepted: 06/19/2013] [Indexed: 01/07/2023]
Abstract
Malignant gliomas are the most devastating and aggressive brain tumors affecting the central nervous system. The insidious growth and infiltration are the most prominent characteristics of malignant gliomas, which render the current therapies for malignant gliomas including surgery, radiation and chemotherapy unsuccessful. Inhibition of infiltration as well as proliferation in combination with surgery might be more effective in the treatment of malignant gliomas. In the current study, we demonstrate the alphaxalone (3-hydroxypregnane-11,20-dione) could effectively inhibit the proliferation of C6 glioma cells in a concentration dependent manner. Moreover, this compound could also suppress the migration and invasion of C6 glioma cells at a concentration without causing significant cytotoxicity. Except the in vitro anti-glioma activity, alphaxalone effectively delayed the growth of rat C6 malignant glioma xenografts in vivo. Together, these findings suggest alphaxalone might be a promising candidate for the treatment of malignant gliomas and may also provide helpful clues for anti-glioma drugs development in future.
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Affiliation(s)
- Huawei Sun
- Department of Cardiology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China
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Chen J, Leng T, Chen W, Yan M, Yin W, Huang Y, Lin S, Duan D, Lin J, Wu G, Zhang J, Yan G. A synthetic steroid 5α-androst-3β,5,6β-triol blocks hypoxia/reoxygenation-induced neuronal injuries via protection of mitochondrial function. Steroids 2013; 78:996-1002. [PMID: 23811019 DOI: 10.1016/j.steroids.2013.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 05/18/2013] [Accepted: 06/09/2013] [Indexed: 10/26/2022]
Abstract
Ischemic stroke is a leading cause of death worldwide, yet therapies are limited. During periods of ischemia following reperfusion in ischemic stroke, not only loss of energy supply, but a few other factors including mitochondrial dysfunction and oxidative stress also make vital contribution to neuronal injury. Here we synthesized a steroid compound 5α-androst-3β,5,6β-triol by 3 steps starting from dehydroepiandrosterone and examined its effect on mitochondrial function and oxidative stress in primary cultured cortical neurons exposed to hypoxia followed by reoxygenation. 5α-Androst-3β,5,6β-triol dose-dependently protected cortical neurons from hypoxia/reoxygenation exposure. Rates of reduction in neuronal viability, loss of mitochondrial membrane potential, disruption of ATP production and oxidative stress were ameliorated in 5α-androst-3β,5,6β-triol pretreated cultures. In summary, these results suggest that 5α-androst-3β,5,6β-triol is neuroprotective against hypoxia/reoxygenation induced neuronal injuries through mediation of mitochondrial function and oxidative stress.
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Affiliation(s)
- Jiesi Chen
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan Road II, Guangzhou 510080, PR China
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Leng T, Lin J, Cottrell JE, Xiong ZG. Subunit and frequency-dependent inhibition of acid sensing ion channels by local anesthetic tetracaine. Mol Pain 2013; 9:27. [PMID: 23758830 PMCID: PMC3695766 DOI: 10.1186/1744-8069-9-27] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 06/05/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Extracellular acidosis is a prominent feature of multiple pathological conditions, correlating with pain sensation. Acid-sensing ion channels (ASICs), a family of proton-gated cation channels, are distributed throughout the central and peripheral nervous systems. Activation of ASICs, particularly ASIC3 and ASIC1a channels, by acidic pH and the resultant depolarization of nociceptive primary sensory neurons, participates in nociception. Agents that inhibit the activation of ASICs are thus expected to be analgesic. Here, we studied the effect of local anesthetic tetracaine on ASIC currents. RESULTS Tetracaine inhibited the peak ASIC3 current in a concentration-dependent manner with an IC50 of 9.96 ± 1.88 mM. The degree of inhibition by tetracaine was dependent on the extracellular pH but independent of the membrane potential. Furthermore, 3 mM tetracaine also inhibited 29.83% of the sustained ASIC3 current. In addition to ASIC3, tetracaine inhibited the ASIC1a and ASIC1β currents. The inhibition of the ASIC1a current was influenced by the frequency of channel activation. In contrast to ASIC3, ASIC1a, and ASIC1β currents, ASIC2a current was not inhibited by tetracaine. In cultured mouse dorsal root ganglion neurons, 1-3 mM tetracaine inhibited both the transient and sustained ASIC currents. At pH4.5, 3 mM tetracaine reduced the peak ASIC current to 60.06 ± 4.51%, and the sustained current to 48.24 ± 7.02% of the control values in dorsal root ganglion neurons. In contrast to ASICs, voltage-gated sodium channels were inhibited by acid, with 55.15% inhibition at pH6.0 and complete inhibition at pH5.0. CONCLUSIONS These findings disclose a potential new mechanism underlying the analgesic effects of local anesthetics, particularly in acidic conditions where their primary target (i.e. voltage-gated Na+ channel) has been suppressed by protons.
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Leng T, Jaben K, Zheng L, Yang J, Paulus Y, Moshfeghi A, Maltenfort M, Campbell P, Ratliff J, Moshfeghi D. The influence of medical school and residency training program upon choice of an academic career and academic productivity among otolaryngology faculty in the United States of America: Our experience of 1433 academic otolaryngologists. Clin Otolaryngol 2012; 37:58-62. [DOI: 10.1111/j.1749-4486.2011.02402.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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32
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Shu M, Zheng X, Wu S, Lu H, Leng T, Zhu W, Zhou Y, Ou Y, Lin X, Lin Y, Xu D, Zhou Y, Yan G. Targeting oncogenic miR-335 inhibits growth and invasion of malignant astrocytoma cells. Mol Cancer 2011; 10:59. [PMID: 21592405 PMCID: PMC3129318 DOI: 10.1186/1476-4598-10-59] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Accepted: 05/19/2011] [Indexed: 01/19/2023] Open
Abstract
Background Astrocytomas are the most common and aggressive brain tumors characterized by their highly invasive growth. Gain of chromosome 7 with a hot spot at 7q32 appears to be the most prominent aberration in astrocytoma. Previously reports have shown that microRNA-335 (miR-335) resided on chromosome 7q32 is deregulated in many cancers; however, the biological function of miR-335 in astrocytoma has yet to be elucidated. Results We report that miR-335 acts as a tumor promoter in conferring tumorigenic features such as growth and invasion on malignant astrocytoma. The miR-335 level is highly elevated in C6 astrocytoma cells and human malignant astrocytomas. Ectopic expression of miR-335 in C6 cells dramatically enhances cell viability, colony-forming ability and invasiveness. Conversely, delivery of antagonist specific for miR-335 (antagomir-335) to C6 cells results in growth arrest, cell apoptosis, invasion repression and marked regression of astrocytoma xenografts. Further investigation reveals that miR-335 targets disheveled-associated activator of morphogenesis 1(Daam1) at posttranscriptional level. Moreover, silencing of endogenous Daam1 (siDaam1) could mimic the oncogenic effects of miR-335 and reverse the growth arrest, proapoptotic and invasion repression effects induced by antagomir-335. Notably, the oncogenic effects of miR-335 and siDAAM1 together with anti-tumor effects of antagomir-335 are also confirmed in human astrocytoma U87-MG cells. Conclusion These findings suggest an oncogenic role of miR-335 and shed new lights on the therapy of malignant astrocytomas by targeting miR-335.
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Affiliation(s)
- Minfeng Shu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
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Li J, Zhu W, Leng T, Shu M, Huang Y, Xu D, Qiu P, Su X, Yan G. Triptolide-induced cell cycle arrest and apoptosis in human renal cell carcinoma cells. Oncol Rep 2011; 25:979-87. [PMID: 21271220 DOI: 10.3892/or.2011.1158] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 12/03/2010] [Indexed: 11/06/2022] Open
Abstract
Renal cell carcinoma (RCC) is the most frequent type of renal-originated malignancy. Although nephrectomy is successfully used to save the lives of patients with localized RCC, treatment of advanced and other refractory RCCs is poor and still inadequate. Here, we show that triptolide, a small molecule and a well-known anti-inflammatory and anti-immunity agent used in the clinic, is capable of inducing cell apoptosis via the mitochondrial pathway in the 786-0 RCC cell line. This induction occurred in concert with reduced expression of genes related to the stabilization of mitochondria such as Bcl-2 and Bcl-XL. Cell cycle analysis showed that exposure to triptolide decreased the proportion of cells in the G0/G1 and G2/M phases, and increased the proportion of cells in the S phase. Cell accumulation in the S phase can be attributed to reduced expression of cell cycle checkpoint regulators such as cyclin A, cyclin B, CDK1, CDK2 and retinoblastoma proteins (Rb). These results raise the possibility that triptolide-induced apoptosis is mediated by cell cycle arrest. Similarly, in another human RCC cell line, OS-RC-2, triptolide-induced apoptosis and cell accumulation in S phase were also observed. Therefore, triptolide emerges as a stimulator of apoptosis by influencing coordinate regulation of proliferation and apoptosis, and may be applicable to the treatment of human renal cell carcinoma.
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Affiliation(s)
- Jingjie Li
- Department of Pharmacology, Zhong-shan School of Medicine, Sun Yat-Sen University, Guangzhou, PR China
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Wu B, He ZJ, Leng T. Evidence for a sequential surface integration process hypothesis from judging egocentric distance with restricted view of the ground. J Vis 2010. [DOI: 10.1167/3.9.500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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36
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37
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Leng T, He ZJ. On the initiation and spreading of interocular suppression from binocular vertical contours. J Vis 2010. [DOI: 10.1167/3.9.452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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38
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Yarbrough GL, Wu B, Wu J, J. He Z, Leng T. Judgments of object location behind an obstacle depend on the particular information selected. J Vis 2010. [DOI: 10.1167/2.7.625] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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39
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Zhu W, He S, Li Y, Qiu P, Shu M, Ou Y, Zhou Y, Leng T, Xie J, Zheng X, Xu D, Su X, Yan G. Anti-angiogenic activity of triptolide in anaplastic thyroid carcinoma is mediated by targeting vascular endothelial and tumor cells. Vascul Pharmacol 2009; 52:46-54. [PMID: 19854299 DOI: 10.1016/j.vph.2009.10.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 09/29/2009] [Accepted: 10/14/2009] [Indexed: 11/16/2022]
Abstract
Triptolide is confirmed to suppress angiogenesis of anaplastic thyroid carcinoma. Here we further expound the precise mechanism involved in this activity. Triptolide downregulated nuclear factor kappa B (NF-kappaB) pathway and its targeting genes associated with endothelial cell mobilization in human umbilical vein endothelial cells (HUVECs) and impaired VEGF expression in thyroid carcinoma TA-K cells. Furthermore, both triptolide and the conditioned medium from triptolide-treated TA-K cells (CMT) significantly attenuated proliferation, migration and tube formation of HUVECs. In vivo, triptolide inhibited TA-K cell-induced tumor growth, vascular formation and VEGF expression. Our data establish that triptolide inhibits tumor angiogenesis by the dual action on vascular endothelial cells and tumor cells, thus providing a novel and overall explanation for the anti-angiogenesis action of triptolide. The multicellular targets emphasize triptolide as a high-performance and potential angiogenesis inhibitor.
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Affiliation(s)
- Wenbo Zhu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China
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Wang Y, Zhang R, Li W, Feng Y, Leng T. Serious Antimicrobial Resistance Status of Pathogens Causing Hospital-acquired Lower Respiratory Tract Infections in North China. J Int Med Res 2009; 37:899-907. [PMID: 19589276 DOI: 10.1177/147323000903700336] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Antimicrobial resistance patterns of pathogens causing hospital-acquired lower respiratory tract infections (LRTIs) in Shandong Province, China were investigated using data collected from January 2002 to December 2006. A total of 10337 isolates were characterized in sputum samples from 39 920 LRTI patients: 68.72% were Gram-negative bacteria, 20.65% were Gram-positive bacteria, and 10.62% were fungi. Organisms most frequently isolated were: Pseudomonas aeruginosa (16.88%), Klebsiella pneumoniae (10.80%), Escherichia coli (10.71%), fungi (10.62%), Staphylococcus aureus (9.68%) and Acinetobacter baumannii (9.03%). Imipenem was the most effective antibiotic against Gram-negative bacteria. Most Gram-positive bacteria were susceptible to vancomycin. Susceptibility to cephalosporins was not optimal and resistance to fluoroquinolones was high. Resistance of Gram-negative bacteria showed a rapid increase over the study period, while resistance of Gram-positive bacteria remained relatively stable. The emergence of resistance to commonly prescribed antimicrobial agents used against LRTI pathogens has compounded the problem of using empirical therapy and created selective pressure on physicians to use certain antibiotics.
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Affiliation(s)
- Y Wang
- Provincial Hospital affiliated to Shandong University, Jinan, China
| | - R Zhang
- Shandong Medical College, Jinan, China
| | - W Li
- Provincial Hospital affiliated to Shandong University, Jinan, China
| | - Y Feng
- Provincial Hospital affiliated to Shandong University, Jinan, China
| | - T Leng
- Provincial Hospital affiliated to Shandong University, Jinan, China
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Molnar FE, Yellachich D, Leng T, Agurto R, Quiroz H, Dalal R, Huie P, Noolandi J, Blumenkranz MS, Marmor MF, Fishman HA. Behavioural difference of vascularized and non-vascularized retina after subretinal implantation of cellulose acetate membrane. J Vis 2004. [DOI: 10.1167/4.11.70] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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42
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Su Y, Leng T, He ZJ. Surface and motion integration determined by luminance contrast polarity. J Vis 2004. [DOI: 10.1167/4.8.888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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43
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Leng T, Zhao Y, Zhang B, Dai H, Yang Q, Zhang X, Gao Y, Li T, Mi J. [Influence of pavulon on facial nerve monitoring during middle ear-mastoid operation]. Lin Chuang Er Bi Yan Hou Ke Za Zhi 1999; 13:490-2. [PMID: 12541369] [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: 02/28/2023]
Abstract
OBJECTIVE To evaluate the influence of pavulon (muscle relaxant) on facial nerve monitoring for patient with middle ear-mastoid operation during general anesthesia. METHOD Intraoperative monitoring of the facial nerve (FNM) was done in 45 ears (44 case). For patient with middle ear-mastoid disease, 38 ears underwent inhaled-intravenous anesthesia with muscle relaxant pavulon (group of general anesthesia), 7 ears underwent local anesthesia (group of local anesthesia). Accelography (ACCG) was used in 10 case for testing the correlation between of FNM and the various degree of recovery from ulnar nerve-musculor blockade. RESULT FNM could be elicited during different periods of recovery with values of T4/T1 varying from 10%-98%. Pavulon could be used to eliminate muscular vibration from disturbing FNM. Electromyography (EMG) potentials were successfully recorded in 34 ears (89.4%). Anesthesia was uneventful and it may be controled satisfactority. CONCLUSION Considering the advantage of pavulon. It can be used for general anesthesia during intraoperative monitoring of the facial nerve for children or adults suffering from local complicated diseases.
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Affiliation(s)
- T Leng
- Department of Otolaryngology, Tongren Hospital, Beijing 100730
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44
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Ni D, Leng T, Dai H. [The challenge of congenital and hereditary diseases]. Zhonghua Er Bi Yan Hou Ke Za Zhi 1999; 34:268-70. [PMID: 12764818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
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45
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Liu Z, Leng T, Li F. [Malignant external otitis: 4 cases report]. Lin Chuang Er Bi Yan Hou Ke Za Zhi 1999; 13:298-9. [PMID: 12541342] [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: 02/28/2023]
Abstract
OBJECTIVE To improve the level of diagnosis and treatment of malignant external otitis (MEO). METHOD Four cases with MEO were reported. RESULT Three in four cases were followed up. One patient was cured, and the others died of intracranial infection. CONCLUSION Early diagnosis of MEO is very important for treatment. The patients of MEO with diabetes often died of intracranial infection.
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Affiliation(s)
- Z Liu
- Department of Otorhinolaryngology, Head and Neck Surgery, Tongren Hospital, Beijing 100730
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46
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Leng T, Li X, Zhao S. [Facial nerve protection during surgery for congenital malformation of the external and middle ear (review of 519 cases)]. Zhonghua Er Bi Yan Hou Ke Za Zhi 1997; 32:11-4. [PMID: 10743118] [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: 02/16/2023]
Abstract
The prevention of facial nerve injury in otoplasty for ear malformation is important. This paper analysed 519 cases of ear malformation collected during 10 years from 1985 to 1995. The hearing of 428 cases was improved, of which the hearing of 221 cases did recover to available level. A long-term follow-up of 198 cases showed that 152 cases had kept the same hearing level as that immediately after surgery. In 130 cases with single middle ear malformation the malformation rate of facial nerve was 60.8%(79/130), and that for chorda tympani 5.4% (7/130). In 75 cases of middle ear malformation with stricture of external acoustic meatus the malformation rate of facial nerve was 60.0% (45/75), and that for chorda tympani 13.3%(10/75). In 314 cases of middle ear malformation with atresia of external acoustic meatus the malformation rate of facial nerve was 42.5%(142/314), and that for chorda tympani nerve 100.0%(314/314). Two cases(0.4%) were of surgical facial nerve paralysis. For protection of facial nerve, it was important to master the anatomy of temporal bone and have a high-resolution computed tomographic scanning to identify facial nerve. It was also important to use electroneurographic monitoring when necessary.
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Leng T. [Simultaneous total ear reconstruction and hearing rehabilitation]. Zhonghua Zheng Xing Shao Shang Wai Ke Za Zhi 1997; 13:5-8. [PMID: 9812438] [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: 02/09/2023]
Abstract
One hundred and fifty-eight patients with congenital microtia and atresia were treated with simultaneous total ear reconstruction and hearing rehabilitation including meatoplasty, tympanoplasty as well as fenestration. Using this operation, the authors have reconstructed 160 auricles and simultaneously restored their auditory function. After the operation, the hearing gain reached 20-45 dB in 132 cases (82.5%). The success rate of the reconstructed ear was 158/160 (98.2%). Most of the reconstructed ears were of excellent appearance.
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Affiliation(s)
- T Leng
- Tongren Hospital, Beijing
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48
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Zhu S, Chen S, Huo Y, Leng T, Suo J. [Study of relationship between the bacteria in air and the clinic infection]. Wei Sheng Wu Xue Bao 1996; 36:394-7. [PMID: 9639826] [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: 02/07/2023]
Abstract
The Source of infectious bacteria is the first problem in provension of infection considered by the medical workers. In this paper, with the method of bacteria plasmid analysis, chromosome DNA restriction fragment length polymorphism analysis, drug resistance experiment (antibacterial drug, sterilizing drug) and so on. We confirmed that staphylococci of nosocomi is mainly from air; but the gram-negative bacteria is mainly from the patient's pharyngeal portion; and cause hospital infection indirectly. The drug resistance of gram-negative from air was lower than the same gram-negative bacilli's isolated from the patient. Moreover, kill bacteria the infectious strain is same strain in air. Above-mentioed results provided the important basis for control of the hoslpital infection.
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Affiliation(s)
- S Zhu
- Chinese PLA General Hospital, Beijing
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49
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Leng T. [The confounding factor and interaction in studies of pathogenesis--an analysis of the secondary infection of viral hepatitis with corticoid therapy]. Zhonghua Liu Xing Bing Xue Za Zhi 1993; 14:279-82. [PMID: 8137409] [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: 01/29/2023]
Abstract
A total of 762 cases of viral hepatitis admitted to the two teaching hospitals of the Third Military Medical College were used for study. They were divided into two groups depending upon whether corticoid treatment was given. As the result of cRR = 6.06, chi 2 = 174.16, P < 0.01, it is obvious that the corticoid therapy is a risk factor for the secondary infection in patients suffered from viral hepatitis. For getting rid of the interference of confounding factor and interaction a stratified analysis was performed. These patients were again divided into severe type and moderate type according to the severity of the disease. The results of stratified analysis were aRR (F) = 3.05 and aRR (F) = 1.48, cRR > aRR. These findings demonstrated that the degree of severity of patients played a primary role in the secondary infection of hepatitis and showed that the confounding factor was present. On the other hand, the result of aRR (F) not equal to aRR (F) indicated that the interaction also existed simultaneously. This study suggests that special attention should be paid to maintain and increase the level of immunological defence function in patients with hepatitis. And, it is necessary to restrict the indiscriminate usage of corticoids, particularly in severe patients, for preventing nosocomial infection.
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Affiliation(s)
- T Leng
- Department of Epidemiology, Third Military Medical College, Chongqing
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50
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Grubb WB, Townsend DE, Ashdown N, Tjia T, McGlashan C, Leng T. Genetic analysis of methicillin-resistant Staphylococcus aureus from Singapore hospitals. Eur J Clin Microbiol 1986; 5:728-30. [PMID: 3492377 DOI: 10.1007/bf02013314] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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