Since the discovery of acid-sensing ion channels in 1997, their importance in the health of neurons and other non-neuronal cells has gained significant importance. Acid-sensing ion channels play important roles in med...Since the discovery of acid-sensing ion channels in 1997, their importance in the health of neurons and other non-neuronal cells has gained significant importance. Acid-sensing ion channels play important roles in mediating pain sensation during diseases such as stroke, inflammation, arthritis, cancer, and recently migraine. More interestingly, acid-sensing ion channels may explain the sex differences in pain between males and females. Also, the ability of acid-sensing ion channel blockers to exert neuroprotective effects in a number of neurodegenerative diseases has added a new dimension to their therapeutic value. The current failure rate of ～45% of new drugs(due to toxicity issues) and saving of up to 7 years in the life span of drug approval makes drug repurposing a high priority. If acid-sensing ion channels' blockers undergo what is known as "drug repurposing", there is a great potential to bring them as medications with known safety profiles to new patient populations. However, the route of administration remains a big challenge due to their poor penetration of the blood brain and retinal barriers. In this review, the promise of using acid-sensing ion channel blockers as neuroprotective drugs is discussed.展开更多
Activation of acid-sensing ion channels （ASICs） plays an important role in neuroinflammation. Macrophage recruitment to the sites of inflammation is an essential step in host defense. ASIC1 and ASIC3 have been repor...Activation of acid-sensing ion channels （ASICs） plays an important role in neuroinflammation. Macrophage recruitment to the sites of inflammation is an essential step in host defense. ASIC1 and ASIC3 have been reported to mediate the endocytosis and maturation of bone marrow derived macrophages. However, the expression and inflammation-related functions of ASICs in RAW 264.7 cells, another common macrophage, are still elusive. In the present study, we first demonstrated the presence of ASIC 1, ASIC2a and ASIC3 in RAW 264.7 macrophage cell line by using reverse transcriptase polymerase chain reaction （RT-PCR）, Western blotting and immunofluorescence experiments. The non-specific ASICs inhibitor amiloride and specific homomeric ASICla blocker PcTxl reduced the production of iNOS and COX-2 by LPS-induced activating RAW 264.7 cells. Furthermore, not only amiloride but also PcTxl inhibited the migration and LPS-induced apoptosis of RAW 264.7 cells. Taken together, our findings suggest that ASICs promote the inflammatory response and apoptosis of RAW 264.7 cells, and ASICs may serve as a potential novel target for immunological disease therapy.展开更多
Acidosis is a common characteristic of brain damage. Because studies have shown that permeable Ca2＋-acid-sensing ion channels can mediate the toxic effects of calcium ions, they have become new targets against pain a...Acidosis is a common characteristic of brain damage. Because studies have shown that permeable Ca2＋-acid-sensing ion channels can mediate the toxic effects of calcium ions, they have become new targets against pain and various intracranial diseases. However, the mechanism associated with expression of these channels remains unclear. This study sought to observe the expression characteristics of permeable Ca2＋-acid-sensing ion channels during different reperfusion inflows in rats after cerebral ischemia. The rat models were randomly divided into three groups： adaptive ischemia/reperfusion group, one-time ischemia/reperfusion group, and severe cerebral ischemic injury group. Western blot assays and immunofluorescence staining results exhibited that when compared with the one-time ischemia/reperfusion group, acid-sensing ion channel 3 and Bcl-x/I expression decreased in the adaptive ischemia/reperfusion group. Calmodulin expression was lowest in the adaptive ischemia/reperfusion group. Following adaptive reperfusion, common carotid artery flow was close to normal, and the pH value improved. Results verified that adaptive reperfusion following cerebral ischemia can suppress acid-sensing ion channel 3 expression, significantly reduce Ca2＋ influx, inhibit calcium overload, and diminish Ca2＋ toxicity. The effects of adaptive ischemia/reperfusion on suppressing cell apoptosis and relieving brain damage were better than that of one-time ischemia/reperfusion.展开更多
In the retina, pH fluctuations may play an important role in adapting retinal responses to different light intensities and are involved in the fine tuning of visual perception. Acidosis occurs in the subretinal space ...In the retina, pH fluctuations may play an important role in adapting retinal responses to different light intensities and are involved in the fine tuning of visual perception. Acidosis occurs in the subretinal space （SRS） under pathological conditions such as age-related macular degeneration （AMD）. Although it is well known that many transporters in the retinal pigment epithelium （RPE） cells can maintain pH homeostasis efficiently, other receptors in RPE may also be involved in sensing acidosis, such as acid-sensing ion channels （ASICs）. In this study, we investigated whether ASICla was ex- pressed in the RPE cells and whether it was involved in the function of these cells. Real-time RT-PCR and Western blotting were used to analyze the ASICla expression in ARPE-19 cells during oxidative stress induced by hydrogen peroxide （H202）. Furthermore, inhibition or over-expression of ASICla in RPE cells was obtained using inhibitors （amiloride and PCTxl） or by the transfection of cDNA encod- ing hASICla. Cell viability was determined by using the MTT assay. The real-time RT-PCR and West- ern blotting results showed that both the mRNA and protein of ASICla were expressed in RPE cells. In- hibition of ASICs by amiloride in normal RPE cells resulted in cell death, indicating that ASICs play an important physiological role in RPE cells. Furthermore, over-expression of ASICla in RPE cells pro- longed cell survival under oxidative stress induced by H2O2. In conclusion, ASICla is functionally expressed in RPE cells and may play an important role in the physiological function of RPE cells by pro-tecting them from oxidative stress.展开更多
Ischemic postconditioning renders brain tissue tolerant to brain ischemia,thereby alleviating ischemic brain injury.However,the exact mechanism of action is still unclear.In this study,a rat model of global brain isch...Ischemic postconditioning renders brain tissue tolerant to brain ischemia,thereby alleviating ischemic brain injury.However,the exact mechanism of action is still unclear.In this study,a rat model of global brain ischemia was subjected to ischemic postconditioning treatment using the vessel occlusion method.After 2 hours of ischemia,the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds.This procedure was repeated six times.Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia,and up-regulate acid-sensing ion channel 2a expression at the m RNA and protein level.These findings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippocampus after global brain ischemia,which promotes neuronal tolerance to ischemic brain injury.展开更多
Acidosis in local environment plays a critical role in cell injury. One key mediator of acidosis-induced cell injury is the acid-sensing ion channels (ASICs), particularly ASIC1a. Herein, we investigated the role of A...Acidosis in local environment plays a critical role in cell injury. One key mediator of acidosis-induced cell injury is the acid-sensing ion channels (ASICs), particularly ASIC1a. Herein, we investigated the role of ASIC1a in acid-induced vascular endothelial cell injury of Henoch-Schonlein purpura (HSP) children. Acid-induced ASIC1a, Calpain and Calcineurin expression in vascular endothelial cells pretreated with IgA1 isolated from HSP were detected by real time quantitative polymerase chain reaction and western blot methods, respectively. Cell cytotoxicity was measured by interleukin-8 and nitric oxide production with ELISA. The results showed acid-induced ASIC1a, Calpain and Calcineurin expression in cells increased, especially at PH6.5. The cytotoxicity of vascular endothelial cells was increased by extracellular acidosis. Moreover non-specific or specific blockers of ASIC1a, Amiloride and PcTX-1 could remarkably decrease these parameters. These findings show that increased [Ca<sup>2+</sup>]i, mediated via ASIC1a, might contribute to acid-induced vascular endothelial cell injury of HSP.展开更多
酸敏感离子通道(acid sensing ion channels,ASICs)是一种可以被H+激活的质子门控阳离子通道。近年来研究发现,酸敏感离子通道参与癫痫、炎症性疼痛、缺血性脑损伤等神经系统相关疾病的病理过程,它被认为是治疗神经系统相关疾病药物作...酸敏感离子通道(acid sensing ion channels,ASICs)是一种可以被H+激活的质子门控阳离子通道。近年来研究发现,酸敏感离子通道参与癫痫、炎症性疼痛、缺血性脑损伤等神经系统相关疾病的病理过程,它被认为是治疗神经系统相关疾病药物作用的一个新靶点。本文主要综述酸敏感离子通道在神经系统相关疾病中的调节作用,以及酸敏感离子通道相关药物的最新研究进展。展开更多
目的探讨幽门螺杆菌(Helicobacter pylori,Hp)感染患儿胃黏膜中酸敏感离子通道(acid-sensing ion channels,ASICs)的表达及其在Hp感染胃炎胃肠功能中的作用。方法将22例经内镜诊断的胃炎患者分为幽门螺杆菌阳性组[Hp(+),n=11]和阴性组[H...目的探讨幽门螺杆菌(Helicobacter pylori,Hp)感染患儿胃黏膜中酸敏感离子通道(acid-sensing ion channels,ASICs)的表达及其在Hp感染胃炎胃肠功能中的作用。方法将22例经内镜诊断的胃炎患者分为幽门螺杆菌阳性组[Hp(+),n=11]和阴性组[Hp(-),n=11]。免疫化学法检测胃炎患儿胃黏膜中ASICs的表达和定位。ELISA法测定血清CCK、SP、GAS和MTL水平。采用Pearson相关性分析ASIC3表达与胃肠道激素的相关性。结果 Hp感染患者胃黏膜ASIC3表达明显升高,血清CCK、SP、MTL水平明显升高。血清CCK、SP、MTL水平与ASIC3表达密切相关。结论 Hp可诱导胃黏膜ASIC3的表达,其影响Hp感染患者的胃肠激素分泌和胃肠功能。展开更多
OBJECTIVE:To investigate the impact of electro-acupuncture at the Neiguan(PC 6) acupoint on protein and RNA expression of acid-sensing ion channel 2(ASIC2) and ASIC3 in myocardial ischemia rats.METHODS:Fifty male Spra...OBJECTIVE:To investigate the impact of electro-acupuncture at the Neiguan(PC 6) acupoint on protein and RNA expression of acid-sensing ion channel 2(ASIC2) and ASIC3 in myocardial ischemia rats.METHODS:Fifty male Sprague-Dawley rats were used,weighing(230 ± 50) g.The rats were randomized into a normal group A,model group B,Neiguan(PC 6) group C,Lieque(LU 7) group D,and A-shi points group E.There were 10 rats in each group.Rats were continuously administered 85 mg/kg intravenous isoproterenol daily to establish the model.Successfully modeled rats in groups C,D,and E were given electro-acupuncture treatment.Each group of rats was sacrificed with chloral hydrate(1 mL/100 g) intraperitoneal injection.The left ventricular myocardium was extracted and placed at- 70 ℃ until use.Western blot analysis and real-time PCR were performed to assay protein and RNA expressions of ASIC2 and ASIC3,respectively.Fold changes in RNA expression were quantified with the 2~^(-△△Ct) method.Blood samples were drawn from the aorta abdominalis and tested for creatine kinase-MB(CK-MB) and lactate dehydrogenase(LDH) levels using enzyme-linked immunosorbent assay.RESULTS:Myocardial ischemia rats given electro-acupuncture at the Neiguan(PC 6) acupoint had significantly lower protein and RNA expression of ASIC2 and ASIC3,and CK-MB and LDH levels,compared with model rats(P < 0.01).CONCLUSION:Electro-acupuncture at the Neiguan(PC 6) acupoint can not only decrease the protein and RNA expression of ASIC2 and ASIC3,but also inhibit the opening of ASICs and reduce the cardiomyocyte damage in myocardial ischemia rats.展开更多
基金supported by the BrightFocus Foundation and intramural grant from North Texas Health Science Center at Fort Worth(to AD)
文摘Since the discovery of acid-sensing ion channels in 1997, their importance in the health of neurons and other non-neuronal cells has gained significant importance. Acid-sensing ion channels play important roles in mediating pain sensation during diseases such as stroke, inflammation, arthritis, cancer, and recently migraine. More interestingly, acid-sensing ion channels may explain the sex differences in pain between males and females. Also, the ability of acid-sensing ion channel blockers to exert neuroprotective effects in a number of neurodegenerative diseases has added a new dimension to their therapeutic value. The current failure rate of ～45% of new drugs(due to toxicity issues) and saving of up to 7 years in the life span of drug approval makes drug repurposing a high priority. If acid-sensing ion channels' blockers undergo what is known as "drug repurposing", there is a great potential to bring them as medications with known safety profiles to new patient populations. However, the route of administration remains a big challenge due to their poor penetration of the blood brain and retinal barriers. In this review, the promise of using acid-sensing ion channel blockers as neuroprotective drugs is discussed.
基金This work was supported by grants from the National Natural science Foundation of China （No. 81473199）, and the Fundamental Research Funds for the Central Universities （No, 015TS 125）.
文摘Activation of acid-sensing ion channels （ASICs） plays an important role in neuroinflammation. Macrophage recruitment to the sites of inflammation is an essential step in host defense. ASIC1 and ASIC3 have been reported to mediate the endocytosis and maturation of bone marrow derived macrophages. However, the expression and inflammation-related functions of ASICs in RAW 264.7 cells, another common macrophage, are still elusive. In the present study, we first demonstrated the presence of ASIC 1, ASIC2a and ASIC3 in RAW 264.7 macrophage cell line by using reverse transcriptase polymerase chain reaction （RT-PCR）, Western blotting and immunofluorescence experiments. The non-specific ASICs inhibitor amiloride and specific homomeric ASICla blocker PcTxl reduced the production of iNOS and COX-2 by LPS-induced activating RAW 264.7 cells. Furthermore, not only amiloride but also PcTxl inhibited the migration and LPS-induced apoptosis of RAW 264.7 cells. Taken together, our findings suggest that ASICs promote the inflammatory response and apoptosis of RAW 264.7 cells, and ASICs may serve as a potential novel target for immunological disease therapy.
基金supported by the National Natural Science Foundation of China,No.30872665
文摘Acidosis is a common characteristic of brain damage. Because studies have shown that permeable Ca2＋-acid-sensing ion channels can mediate the toxic effects of calcium ions, they have become new targets against pain and various intracranial diseases. However, the mechanism associated with expression of these channels remains unclear. This study sought to observe the expression characteristics of permeable Ca2＋-acid-sensing ion channels during different reperfusion inflows in rats after cerebral ischemia. The rat models were randomly divided into three groups： adaptive ischemia/reperfusion group, one-time ischemia/reperfusion group, and severe cerebral ischemic injury group. Western blot assays and immunofluorescence staining results exhibited that when compared with the one-time ischemia/reperfusion group, acid-sensing ion channel 3 and Bcl-x/I expression decreased in the adaptive ischemia/reperfusion group. Calmodulin expression was lowest in the adaptive ischemia/reperfusion group. Following adaptive reperfusion, common carotid artery flow was close to normal, and the pH value improved. Results verified that adaptive reperfusion following cerebral ischemia can suppress acid-sensing ion channel 3 expression, significantly reduce Ca2＋ influx, inhibit calcium overload, and diminish Ca2＋ toxicity. The effects of adaptive ischemia/reperfusion on suppressing cell apoptosis and relieving brain damage were better than that of one-time ischemia/reperfusion.
基金supported by the National Natural Science Foundation of China (No. 81200681)
文摘In the retina, pH fluctuations may play an important role in adapting retinal responses to different light intensities and are involved in the fine tuning of visual perception. Acidosis occurs in the subretinal space （SRS） under pathological conditions such as age-related macular degeneration （AMD）. Although it is well known that many transporters in the retinal pigment epithelium （RPE） cells can maintain pH homeostasis efficiently, other receptors in RPE may also be involved in sensing acidosis, such as acid-sensing ion channels （ASICs）. In this study, we investigated whether ASICla was ex- pressed in the RPE cells and whether it was involved in the function of these cells. Real-time RT-PCR and Western blotting were used to analyze the ASICla expression in ARPE-19 cells during oxidative stress induced by hydrogen peroxide （H202）. Furthermore, inhibition or over-expression of ASICla in RPE cells was obtained using inhibitors （amiloride and PCTxl） or by the transfection of cDNA encod- ing hASICla. Cell viability was determined by using the MTT assay. The real-time RT-PCR and West- ern blotting results showed that both the mRNA and protein of ASICla were expressed in RPE cells. In- hibition of ASICs by amiloride in normal RPE cells resulted in cell death, indicating that ASICs play an important physiological role in RPE cells. Furthermore, over-expression of ASICla in RPE cells pro- longed cell survival under oxidative stress induced by H2O2. In conclusion, ASICla is functionally expressed in RPE cells and may play an important role in the physiological function of RPE cells by pro-tecting them from oxidative stress.
文摘Ischemic postconditioning renders brain tissue tolerant to brain ischemia,thereby alleviating ischemic brain injury.However,the exact mechanism of action is still unclear.In this study,a rat model of global brain ischemia was subjected to ischemic postconditioning treatment using the vessel occlusion method.After 2 hours of ischemia,the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds.This procedure was repeated six times.Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia,and up-regulate acid-sensing ion channel 2a expression at the m RNA and protein level.These findings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippocampus after global brain ischemia,which promotes neuronal tolerance to ischemic brain injury.
文摘Acidosis in local environment plays a critical role in cell injury. One key mediator of acidosis-induced cell injury is the acid-sensing ion channels (ASICs), particularly ASIC1a. Herein, we investigated the role of ASIC1a in acid-induced vascular endothelial cell injury of Henoch-Schonlein purpura (HSP) children. Acid-induced ASIC1a, Calpain and Calcineurin expression in vascular endothelial cells pretreated with IgA1 isolated from HSP were detected by real time quantitative polymerase chain reaction and western blot methods, respectively. Cell cytotoxicity was measured by interleukin-8 and nitric oxide production with ELISA. The results showed acid-induced ASIC1a, Calpain and Calcineurin expression in cells increased, especially at PH6.5. The cytotoxicity of vascular endothelial cells was increased by extracellular acidosis. Moreover non-specific or specific blockers of ASIC1a, Amiloride and PcTX-1 could remarkably decrease these parameters. These findings show that increased [Ca<sup>2+</sup>]i, mediated via ASIC1a, might contribute to acid-induced vascular endothelial cell injury of HSP.
文摘酸敏感离子通道(acid sensing ion channels,ASICs)是一种可以被H+激活的质子门控阳离子通道。近年来研究发现,酸敏感离子通道参与癫痫、炎症性疼痛、缺血性脑损伤等神经系统相关疾病的病理过程,它被认为是治疗神经系统相关疾病药物作用的一个新靶点。本文主要综述酸敏感离子通道在神经系统相关疾病中的调节作用,以及酸敏感离子通道相关药物的最新研究进展。
基金Supported by National Essence Basic Research and Development 973 Program(the Effects of Meridian Specific Target Organ Response to Biological Basic Research,No.2012CB518503)
文摘OBJECTIVE:To investigate the impact of electro-acupuncture at the Neiguan(PC 6) acupoint on protein and RNA expression of acid-sensing ion channel 2(ASIC2) and ASIC3 in myocardial ischemia rats.METHODS:Fifty male Sprague-Dawley rats were used,weighing(230 ± 50) g.The rats were randomized into a normal group A,model group B,Neiguan(PC 6) group C,Lieque(LU 7) group D,and A-shi points group E.There were 10 rats in each group.Rats were continuously administered 85 mg/kg intravenous isoproterenol daily to establish the model.Successfully modeled rats in groups C,D,and E were given electro-acupuncture treatment.Each group of rats was sacrificed with chloral hydrate(1 mL/100 g) intraperitoneal injection.The left ventricular myocardium was extracted and placed at- 70 ℃ until use.Western blot analysis and real-time PCR were performed to assay protein and RNA expressions of ASIC2 and ASIC3,respectively.Fold changes in RNA expression were quantified with the 2~^(-△△Ct) method.Blood samples were drawn from the aorta abdominalis and tested for creatine kinase-MB(CK-MB) and lactate dehydrogenase(LDH) levels using enzyme-linked immunosorbent assay.RESULTS:Myocardial ischemia rats given electro-acupuncture at the Neiguan(PC 6) acupoint had significantly lower protein and RNA expression of ASIC2 and ASIC3,and CK-MB and LDH levels,compared with model rats(P < 0.01).CONCLUSION:Electro-acupuncture at the Neiguan(PC 6) acupoint can not only decrease the protein and RNA expression of ASIC2 and ASIC3,but also inhibit the opening of ASICs and reduce the cardiomyocyte damage in myocardial ischemia rats.
