Adenosine triphosphate(ATP)induced cell death(AICD)is a critical cellular process that has garnered substantial scientific interest for its profound relevance to cancer biology and to therapeutic interventions.This co...Adenosine triphosphate(ATP)induced cell death(AICD)is a critical cellular process that has garnered substantial scientific interest for its profound relevance to cancer biology and to therapeutic interventions.This comprehensive review unveils the intricate web of AICD mechanisms and their intricate connections with cancer biology.This review offers a comprehensive framework for comprehending the multifaceted role of AICD in the context of cancer.This is achieved by elucidating the dynamic interplay between systemic and cellular ATP homeostasis,deciphering the intricate mechanisms governing AICD,elucidating its intricate involvement in cancer signaling pathways,and scrutinizing validated key genes.Moreover,the exploration of AICD as a potential avenue for cancer treatment underscores its essential role in shaping the future landscape of cancer therapeutics.展开更多
After hypoxia, ischemia, or inflammatory injuries to the central nervous system, the damaged cells release a large amount of adenosine triphosphate, which may cause secondary neuronal death. Autophagy is a form of cel...After hypoxia, ischemia, or inflammatory injuries to the central nervous system, the damaged cells release a large amount of adenosine triphosphate, which may cause secondary neuronal death. Autophagy is a form of cell death that also has neuroprotective effects. Cell Counting Kit assay, monodansylcadaverine staining, flow cytometry, western blotting, and real-time PCR were used to determine the effects of exogenous adenosine triphosphate treatment at different concentrations (2, 4, 6, 8, 10 mmol/L) over time (1, 2, 3, and 6 hours) on the apoptosis and autophagy of SH-SY5Y cells. High concentrations of extracellular adenosine triphosphate induced autophagy and apoptosis of SH-SYSY cells. The enhanced autophagy first appeared, and peaked at 1 hour after treatment with adenosine triphosphate. Cell apoptosis peaked at 3 hours, and persisted through 6 hours. With prolonged exposure to the adenosine triphosphate treatment, the fraction of apoptotic cells increased. These data suggest that the SH-SY5Y neural cells initiated autophagy against apoptosis within an hour of adenosine triphosphate treatment to protect themselves against injury.展开更多
AIM: To study the growth inhibitory effects of ATP on TE-13 human squamous esophageal carcinoma cellsin vitro.METHODS: NTT assay was used to determine the inhibition of proliferation of ATP or adenosine (ADO) on T...AIM: To study the growth inhibitory effects of ATP on TE-13 human squamous esophageal carcinoma cellsin vitro.METHODS: NTT assay was used to determine the inhibition of proliferation of ATP or adenosine (ADO) on TE-13 cell line. The morphological changes of TE-13 cells induced by ATP or ADO were observed under fluorescence light microscope by acridine orange (AO)/ethidium bromide (EB) double stained cells. The intemudeosomal fragmentation of genomic DNA was detected by agarose gel electrophoresis. The apoptotic rate and cell cycle after treatment with ATP or ADO were determined by flow cytometry.RESULTS: ATP and ADO produced inhibitory effects on TE-13 cells at the concentration between 0.01 and 1.0 mmol/L. The ICs0 of TE-13 cells exposed to ATP or ADO for 48 and 72 h was 0.71 or 1.05, and 0.21 or 0.19 mmol/L, respectively. The distribution of cell cycle phase and proliferation index (PI) value of TE-13 cells changed, when being exposed to ATP or ADO at the concentrations of 0.01, 0.1, and 1 mmol/L for 48 h. ATP and ADO inhibited the cell proliferation by changing the distribution of cell cycle phase via either G0/G1 phase (ATP or ADO, 1 mmol/L) or S phase (ATP, 0.1 mmol/L) arrest. Under light microscope, the tumor cells exposed to 0.3 mmol/L ATP or ADO displayed morphological changes of apoptosis. A ladder-like pattern of DNA fragmentation was obtained from TE-13 cells treated with 0.1-1 mmol/L ATP or ADO in agarose gel electrophoresis. ATP and ADO induced apoptosis of TE-13 cells in a dose-dependent manner at the concentration between 0.03 and 1 mmol/L. The maximum apoptotic rate of TE-13 cells exposed to ATP or ADO for 48 h was 16.63% or 16.9%, respectively.CONCLUSION: ATP and ADO inhibit cell proliferation, arrest cell cycle, and induce apoptosis of TE-13 cell line.展开更多
The mammalian target of rapamycin (mTOR) pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord ...The mammalian target of rapamycin (mTOR) pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord injury, rat models of spinal cord injury were established by modified Allen's stall method and interfered for 7 days by intraperitoneal administration of mTOR activator adenosine triphosphate and mTOR kinase inhibitor rapamycin. At 1-4 weeks after spinal cord injury induction, the Basso, Beattie and Bresnahan locomotor rating scale was used to evaluate rat locomotor function, and immunohistochemical staining and western blot analysis were used to detect the expression of nestin (neural stem cell marker), neuronal nuclei (neuronal marker), neuron specific enolase, neurofilament protein 200 (axonal marker), glial fibrillary acidic protein (astrocyte marker), Akt, mTOR and signal transduction and activator of transcription 3 (STAT3). Results showed that adenosine triphosphate-mediated Akt/mTOR/STAT3 pathway increased endogenous neural stem cells, induced neurogenesis and axonal growth, inhibited excessive astrogliosis and improved the locomotor function of rats with spinal cord injury.展开更多
In this study,we aimed at developing an efficient biocatalytic process for bio-production of cyclic adenosine monophosphate(c AMP)from adenosine triphosphate(ATP).First,adenylate cyclase from Escherichia coli MG1655(E...In this study,we aimed at developing an efficient biocatalytic process for bio-production of cyclic adenosine monophosphate(c AMP)from adenosine triphosphate(ATP).First,adenylate cyclase from Escherichia coli MG1655(EAC)and Bordetella Pertussis(BAC)were expressed in E.coli BL21(DE3)and comparatively analyzed for their activities.As a result,EAC from E.coli MG1655 exhibited a higher activity.However,amount of EAC were obtained in an insoluble form.Therefore,we expressed the first 446 amino acids of EAC(EAC446)to avoid the inclusion body.The effects of induction temperature,incubation time,and incubation p H were further evaluated to improve the expression of EAC446.Subsequently,the reaction process for the production of c AMP with ATP as a starting material was investigated.As none of c AMP was detected in the whole-cell based biocatalytic process,the reaction catalyzed by the crude enzyme was determined for c AMP production.What's more,the reaction temperature,reaction p H,metal ion additives and substrate concentration was optimized,and the maximum c AMP production of 18.45 g·L^-1was achieved with a yield of 95.4%after bioconversion of 6 h.展开更多
AIM:To clarify the protective effect of exogenous adenosine triphosphate(ATP)on hypothermically preserved rat livers. METHODS:Establishment of continuous hypothermic machine perfusion model,detection of nucleotides in...AIM:To clarify the protective effect of exogenous adenosine triphosphate(ATP)on hypothermically preserved rat livers. METHODS:Establishment of continuous hypothermic machine perfusion model,detection of nucleotides in hepatocytes with HPLC,measurement of activities of LDH and AST in the perfusate,observation of histopathological changes in different experiment groups,and autoradiography were carried out to reveal the underlying mechanism of the protective effect of ATP. RESULTS:The intracellular levels of ATP and EC decreased rapidly after hypothermic preservation in control group,while a higher ATP and EC level,and a slower decreasing rate were observed when ATP-MgCl_2 was added to the perfusate (P<0.01).As compared with the control group,the activities of LDH and AST in the ATP-MgCl_2 group were lower(P<0.05). Furthermore,more severe hepatocyte damage and neutrophil infiltration were observed in the control group.Radioactive [α-^(32)P]ATP entered the hypothermically preserved rat hepatocytes. CONCLUSION:Exogenous ATP has a protective effect on rat livers during hypothermical preservation.However,Mg^(2+) is indispensable,addition of ATP alone produces no protective effect.The underlying mechanism may be that exogenous ATP enters the hypothermically preserved rat liver cells.展开更多
Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was app...Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was applied in a rat model, adenosine 5-triphosphate disodium in the extracellular space was broken down into adenosine, which in turn inhibited pain transmission by means of an adenosine A1 receptor-dependent process. Direct injection of an adenosine A1 receptor agonist enhanced the analgesic effect of acupuncture. The analgesic effect of acupuncture appears to be mediated by activation of A1 receptors located on ascending nerves. In neuropathic pain, there is upregulation of P2X purinoceptor 3 (P2X3) receptor expression in dorsal root ganglion neurons. Conversely, the onset of mechanical hyperalgesia was diminished and established hyperalgesia was significantly reversed when P2X3 receptor expression was downregulated. The pathways upon which electroacupuncture appear to act are interwoven with pain pathways, and electroacupuncture stimuli converge with impulses originating from painful areas. Electroacupuncture may act via purinergic A1 and P2X3 receptors simultaneously to induce an analgesic effect on neuropathic pain.展开更多
Nicotinamide adenine dinucleotide (NAD) oscillation was observed when the isolated mitochondria were immersed in a pyruvate solution. In addition, when an adenosine diphosphate (ADP) was added to the mitochondrial sus...Nicotinamide adenine dinucleotide (NAD) oscillation was observed when the isolated mitochondria were immersed in a pyruvate solution. In addition, when an adenosine diphosphate (ADP) was added to the mitochondrial suspension containing pyruvate, adenosine triphosphate (ATP) oscillation was observed as well as NADH oscillation. At this time, the pH within mitochondria also oscillated. It was found that the oscillatory reaction of NADH caused by the membrane permeation of pyruvate continues, causing the oscillation of NADH and H+ in the subsequent reactions. The pH oscillation led to the ATP oscillation. It is considered that the oscillatory reaction caused by the gradual entry of pyruvate into mitochondria was thought to be carried over to both the citric acid cycle and the respiratory chain, ultimately leading to the ATP oscillation in oxidative phosphorylation. Similarly, it was found that membrane permeation of malate causes the gradual occurrence of NADH, at which point NADH oscillates, followed by an oscillatory reaction of the respiratory chain, and finally ATP oscillation. It was found that the oscillations of NADH and ATP occur without going through the citric acid cycle. Oscillations of NADH and other intermediates in both the citric acid cycle and respiratory chain were also confirmed by experiments using semipermeable membranes. These results support our hypothesis that the gradual entry of the substrate by membrane permeation triggers an oscillatory reaction of the enzyme, which is also carried over to subsequent reactions.展开更多
OBJECTIVE:To investigate the mechanisms behind the effects of acupuncture in Traditional Chinese Medicine,we delved into the adenosine triphosphate/peripheral purinergic P2X receptor 3(ATP/P2X3)receptor signaling syst...OBJECTIVE:To investigate the mechanisms behind the effects of acupuncture in Traditional Chinese Medicine,we delved into the adenosine triphosphate/peripheral purinergic P2X receptor 3(ATP/P2X3)receptor signaling system as an indicator of the body's energy state,commonly referred to as"Qi".METHODS:The tail-flick test was utilized to explore the impact of acupuncture on pain tolerance threshold(PTT)in mice,while also assessing adenosine(ADO)levels and adenylate energy charge(EC)at Zusanli(ST36).The study further investigated the dose-dependent effects of acupuncture on PTT and ADO levels at Zusanli(ST36).To shed light on the underlying mechanisms of acupuncture's effects,the study examined the impact of ATP,a P2X3 receptor antagonist,and adenosine disodium on PTT following acupuncture administration.RESULTS:Acupuncture at Zusanli(ST36)led to significant improvements in PTT in mice,with the most effective interventions being twirling for 2 min and needle retention for 28 min.These interventions also resulted in significant increases in ATP levels.The effects of acupuncture were further augmented by administration of different doses of ATP at Zusanli(ST36),and pretreatment with a P2X3 receptor antagonist decreased PTT.Adenylate EC peaked at 30 min after intraperitoneal injection of ATP,and pretreatment with various doses of i.p.ATP 30 min prior to acupuncture increased PTT in a dose-dependent manner.Additionally,pretreatment with an i.p.or intramuscular injection of adenosine disodium enhanced the effects of acupuncture.CONCLUSION:This research provides compelling evidence that ATP is involved in the regulation of PTT through acupuncture,revealing new avenues for achieving enhanced clinical outcomes.展开更多
The activation of adenosine A1 receptors is important for protecting against ischemic brain injury and pretreatment with electroacupuncture has been shown to mitigate ischemic brain insult. The aim of this study was t...The activation of adenosine A1 receptors is important for protecting against ischemic brain injury and pretreatment with electroacupuncture has been shown to mitigate ischemic brain insult. The aim of this study was to test whether the adenosine A1 receptor mediates electroacupuncture pretreatment-induced neuroprotection against ischemic brain injury. We first performed 30 minutes of electroacupuncture pretreatment at the Baihui acupoint(GV20), delivered with a current of 1 mA, a frequency of 2/15 Hz, and a depth of 1 mm. High-performance liquid chromatography found that adenosine triphosphate and adenosine levels peaked in the cerebral cortex at 15 minutes and 120 minutes after electroacupuncture pretreatment, respectively. We further examined the effect of 15 or 120 minutes electroacupuncture treatment on ischemic brain injury in a rat middle cerebral artery-occlusion model. We found that at 24 hours reperfusion,120 minutes after electroacupuncture pretreatment, but not for 15 minutes, significantly reduced behavioral deficits and infarct volumes. Last, we demonstrated that the protective effect gained by 120 minutes after electroacupuncture treatment before ischemic injury was abolished by pretreatment with the A1-receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine(1 mg/kg, intraperitoneally). Our results suggest that pretreatment with electroacupuncture at the Baihui acupoint elicits protection against transient cerebral ischemia via action at adenosine A1 receptors.展开更多
BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism o...BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism of P2Rs in trigeminal neuralgia remains unclear. OBJECTIVE: To investigate changes in the P2R-mediated calcium signaling pathway in nociceptive trigemJnal ganglion neurons. DESIGN, TIME AND SETTING: In vitro experiments were conducted at the Patch-Clamp Laboratory of Comprehensive Experiment Center of Anhui Medical University, China from September 2008 to June 2009. MATERIALS: Thapsigargin, caffeine, suramin, and adenosine 5'-triphosphate were purchased from Sigma, USA. METHODS: Using Fura-2-based microfluorimetry, intracellular calcium concentration ([Ca^2+]i) was measured in freshly isolated adult rat small trigeminal ganglion neurons before and after drug application. MAIN OUTCOME MEASURES: Fluorescent intensities were expressed as the ratio F340/F380 to observe [Ca^2+]i changes. RESULTS: In normal extracellular solution and Ca^2+-free solution, application of thapsigargin (1 μmol/L), a sarcoplasmic reticulum Ca^2+ pump adenosine 5'-triphosphate inhibitor, as well as caffeine (20 mmol/L), a ryanodine receptor agonist, triggered [Ca^2+]i increase in small trigeminal ganglion neurons. A similar response was induced by application of adenosine 5'-triphosphate (100 μmol/L). In Ca^2+-free conditions, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were inhibited in cells pre-treated with thapsigargin (P 〈 0.01), but not by caffeine (P 〉 0.05). In normal, extracellular solution, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were partly inhibited in cells pre-treated with thapsigargin (P 〈 0.05). CONCLUSION: Inositol-1,4, 5-triphosphate (IP3)- and ryanodine-sensitive Ca^2+ stores exist in rat nociceptive trigeminal ganglion neurons. Two pathways are involved in the purinoreceptor-mediated [Ca^2+]i rise observed in nociceptive trigeminal ganglion neurons. One pathway involves the metabotropic P2Y receptors, which are associated with the IP3 sensitive Ca^2+store, and the second pathway is coupled to ionotropic P2X receptors that induce the Ca^2+ influx.展开更多
背景:阿尔茨海默病患者存在严重的脑能量障碍,近年来基于酮体干预的脑能量拯救策略在阿尔茨海默病的治疗中越来越受到重视。目的:探讨β-羟基丁酸能否改善β淀粉样蛋白1-42(β-amyloid protein 1-42,Aβ_(1-42))诱导的小鼠海马神经元HT2...背景:阿尔茨海默病患者存在严重的脑能量障碍,近年来基于酮体干预的脑能量拯救策略在阿尔茨海默病的治疗中越来越受到重视。目的:探讨β-羟基丁酸能否改善β淀粉样蛋白1-42(β-amyloid protein 1-42,Aβ_(1-42))诱导的小鼠海马神经元HT22细胞能量障碍。方法:将HT22细胞分为4组,分别为对照组、β-羟基丁酸组、Aβ_(1-42)组、Aβ_(1-42)+β-羟基丁酸组。使用相应试剂盒检测HT22细胞的存活率、ATP水平、α-酮戊二酸脱氢酶活性、Na^(+)K^(+)-ATP酶活性、线粒体膜电位及活性氧水平。结果与结论:与对照组相比,Aβ_(1-42)组HT22细胞的存活率、ATP水平、α-酮戊二酸脱氢酶活性、Na^(+)K^(+)-ATP酶活性、线粒体膜电位均显著降低(P<0.05),活性氧水平显著升高(P<0.05)。与Aβ_(1-42)组相比,Aβ_(1-42)+β-羟基丁酸组HT22细胞的存活率、ATP水平、α-酮戊二酸脱氢酶活性、Na^(+)K^(+)-ATP酶活性、线粒体膜电位均显著升高(P<0.05),活性氧水平显著降低(P<0.05)。结果表明:β-羟基丁酸提高了线粒体生物能量功能和细胞存活率,最终改善了Aβ_(1-42)诱导的HT22细胞能量障碍。展开更多
基金Supported by National Natural Science Foundation of China,No.81960877University Innovation Fund of Gansu Province,No.2021A-076+4 种基金Gansu Province Science and Technology Plan(Innovation Base and Talent Plan),No.21JR7RA561Natural Science Foundation of Gansu Province,No.21JR1RA267 and No.22JR5RA582Education Technology Innovation Project of Gansu Province,No.2022A-067Innovation Fund of Higher Education of Gansu Province,No.2023A-088Gansu Province Science and Technology Plan International Cooperation Field Project,No.23YFWA0005.
文摘Adenosine triphosphate(ATP)induced cell death(AICD)is a critical cellular process that has garnered substantial scientific interest for its profound relevance to cancer biology and to therapeutic interventions.This comprehensive review unveils the intricate web of AICD mechanisms and their intricate connections with cancer biology.This review offers a comprehensive framework for comprehending the multifaceted role of AICD in the context of cancer.This is achieved by elucidating the dynamic interplay between systemic and cellular ATP homeostasis,deciphering the intricate mechanisms governing AICD,elucidating its intricate involvement in cancer signaling pathways,and scrutinizing validated key genes.Moreover,the exploration of AICD as a potential avenue for cancer treatment underscores its essential role in shaping the future landscape of cancer therapeutics.
基金supported by the National Natural Science Foundation of China,No.81371346,81271376
文摘After hypoxia, ischemia, or inflammatory injuries to the central nervous system, the damaged cells release a large amount of adenosine triphosphate, which may cause secondary neuronal death. Autophagy is a form of cell death that also has neuroprotective effects. Cell Counting Kit assay, monodansylcadaverine staining, flow cytometry, western blotting, and real-time PCR were used to determine the effects of exogenous adenosine triphosphate treatment at different concentrations (2, 4, 6, 8, 10 mmol/L) over time (1, 2, 3, and 6 hours) on the apoptosis and autophagy of SH-SY5Y cells. High concentrations of extracellular adenosine triphosphate induced autophagy and apoptosis of SH-SYSY cells. The enhanced autophagy first appeared, and peaked at 1 hour after treatment with adenosine triphosphate. Cell apoptosis peaked at 3 hours, and persisted through 6 hours. With prolonged exposure to the adenosine triphosphate treatment, the fraction of apoptotic cells increased. These data suggest that the SH-SY5Y neural cells initiated autophagy against apoptosis within an hour of adenosine triphosphate treatment to protect themselves against injury.
基金Supported by the Science and Technology Development Project of Hebei Province, No. 032761192
文摘AIM: To study the growth inhibitory effects of ATP on TE-13 human squamous esophageal carcinoma cellsin vitro.METHODS: NTT assay was used to determine the inhibition of proliferation of ATP or adenosine (ADO) on TE-13 cell line. The morphological changes of TE-13 cells induced by ATP or ADO were observed under fluorescence light microscope by acridine orange (AO)/ethidium bromide (EB) double stained cells. The intemudeosomal fragmentation of genomic DNA was detected by agarose gel electrophoresis. The apoptotic rate and cell cycle after treatment with ATP or ADO were determined by flow cytometry.RESULTS: ATP and ADO produced inhibitory effects on TE-13 cells at the concentration between 0.01 and 1.0 mmol/L. The ICs0 of TE-13 cells exposed to ATP or ADO for 48 and 72 h was 0.71 or 1.05, and 0.21 or 0.19 mmol/L, respectively. The distribution of cell cycle phase and proliferation index (PI) value of TE-13 cells changed, when being exposed to ATP or ADO at the concentrations of 0.01, 0.1, and 1 mmol/L for 48 h. ATP and ADO inhibited the cell proliferation by changing the distribution of cell cycle phase via either G0/G1 phase (ATP or ADO, 1 mmol/L) or S phase (ATP, 0.1 mmol/L) arrest. Under light microscope, the tumor cells exposed to 0.3 mmol/L ATP or ADO displayed morphological changes of apoptosis. A ladder-like pattern of DNA fragmentation was obtained from TE-13 cells treated with 0.1-1 mmol/L ATP or ADO in agarose gel electrophoresis. ATP and ADO induced apoptosis of TE-13 cells in a dose-dependent manner at the concentration between 0.03 and 1 mmol/L. The maximum apoptotic rate of TE-13 cells exposed to ATP or ADO for 48 h was 16.63% or 16.9%, respectively.CONCLUSION: ATP and ADO inhibit cell proliferation, arrest cell cycle, and induce apoptosis of TE-13 cell line.
文摘The mammalian target of rapamycin (mTOR) pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord injury, rat models of spinal cord injury were established by modified Allen's stall method and interfered for 7 days by intraperitoneal administration of mTOR activator adenosine triphosphate and mTOR kinase inhibitor rapamycin. At 1-4 weeks after spinal cord injury induction, the Basso, Beattie and Bresnahan locomotor rating scale was used to evaluate rat locomotor function, and immunohistochemical staining and western blot analysis were used to detect the expression of nestin (neural stem cell marker), neuronal nuclei (neuronal marker), neuron specific enolase, neurofilament protein 200 (axonal marker), glial fibrillary acidic protein (astrocyte marker), Akt, mTOR and signal transduction and activator of transcription 3 (STAT3). Results showed that adenosine triphosphate-mediated Akt/mTOR/STAT3 pathway increased endogenous neural stem cells, induced neurogenesis and axonal growth, inhibited excessive astrogliosis and improved the locomotor function of rats with spinal cord injury.
基金The National Natural Science Foundation of China(Grant No.21576134,Grant No.21606127,Grant No.21390200,Grant No.21706126)the National Key Research and Development Program of China(Grant No.2016YFA0204300)the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions。
文摘In this study,we aimed at developing an efficient biocatalytic process for bio-production of cyclic adenosine monophosphate(c AMP)from adenosine triphosphate(ATP).First,adenylate cyclase from Escherichia coli MG1655(EAC)and Bordetella Pertussis(BAC)were expressed in E.coli BL21(DE3)and comparatively analyzed for their activities.As a result,EAC from E.coli MG1655 exhibited a higher activity.However,amount of EAC were obtained in an insoluble form.Therefore,we expressed the first 446 amino acids of EAC(EAC446)to avoid the inclusion body.The effects of induction temperature,incubation time,and incubation p H were further evaluated to improve the expression of EAC446.Subsequently,the reaction process for the production of c AMP with ATP as a starting material was investigated.As none of c AMP was detected in the whole-cell based biocatalytic process,the reaction catalyzed by the crude enzyme was determined for c AMP production.What's more,the reaction temperature,reaction p H,metal ion additives and substrate concentration was optimized,and the maximum c AMP production of 18.45 g·L^-1was achieved with a yield of 95.4%after bioconversion of 6 h.
文摘AIM:To clarify the protective effect of exogenous adenosine triphosphate(ATP)on hypothermically preserved rat livers. METHODS:Establishment of continuous hypothermic machine perfusion model,detection of nucleotides in hepatocytes with HPLC,measurement of activities of LDH and AST in the perfusate,observation of histopathological changes in different experiment groups,and autoradiography were carried out to reveal the underlying mechanism of the protective effect of ATP. RESULTS:The intracellular levels of ATP and EC decreased rapidly after hypothermic preservation in control group,while a higher ATP and EC level,and a slower decreasing rate were observed when ATP-MgCl_2 was added to the perfusate (P<0.01).As compared with the control group,the activities of LDH and AST in the ATP-MgCl_2 group were lower(P<0.05). Furthermore,more severe hepatocyte damage and neutrophil infiltration were observed in the control group.Radioactive [α-^(32)P]ATP entered the hypothermically preserved rat hepatocytes. CONCLUSION:Exogenous ATP has a protective effect on rat livers during hypothermical preservation.However,Mg^(2+) is indispensable,addition of ATP alone produces no protective effect.The underlying mechanism may be that exogenous ATP enters the hypothermically preserved rat liver cells.
文摘Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was applied in a rat model, adenosine 5-triphosphate disodium in the extracellular space was broken down into adenosine, which in turn inhibited pain transmission by means of an adenosine A1 receptor-dependent process. Direct injection of an adenosine A1 receptor agonist enhanced the analgesic effect of acupuncture. The analgesic effect of acupuncture appears to be mediated by activation of A1 receptors located on ascending nerves. In neuropathic pain, there is upregulation of P2X purinoceptor 3 (P2X3) receptor expression in dorsal root ganglion neurons. Conversely, the onset of mechanical hyperalgesia was diminished and established hyperalgesia was significantly reversed when P2X3 receptor expression was downregulated. The pathways upon which electroacupuncture appear to act are interwoven with pain pathways, and electroacupuncture stimuli converge with impulses originating from painful areas. Electroacupuncture may act via purinergic A1 and P2X3 receptors simultaneously to induce an analgesic effect on neuropathic pain.
文摘Nicotinamide adenine dinucleotide (NAD) oscillation was observed when the isolated mitochondria were immersed in a pyruvate solution. In addition, when an adenosine diphosphate (ADP) was added to the mitochondrial suspension containing pyruvate, adenosine triphosphate (ATP) oscillation was observed as well as NADH oscillation. At this time, the pH within mitochondria also oscillated. It was found that the oscillatory reaction of NADH caused by the membrane permeation of pyruvate continues, causing the oscillation of NADH and H+ in the subsequent reactions. The pH oscillation led to the ATP oscillation. It is considered that the oscillatory reaction caused by the gradual entry of pyruvate into mitochondria was thought to be carried over to both the citric acid cycle and the respiratory chain, ultimately leading to the ATP oscillation in oxidative phosphorylation. Similarly, it was found that membrane permeation of malate causes the gradual occurrence of NADH, at which point NADH oscillates, followed by an oscillatory reaction of the respiratory chain, and finally ATP oscillation. It was found that the oscillations of NADH and ATP occur without going through the citric acid cycle. Oscillations of NADH and other intermediates in both the citric acid cycle and respiratory chain were also confirmed by experiments using semipermeable membranes. These results support our hypothesis that the gradual entry of the substrate by membrane permeation triggers an oscillatory reaction of the enzyme, which is also carried over to subsequent reactions.
基金The National Key R&D Program of China:Biological Mechanisms of Acupoint Function-Effect Associations(No.2019YFC1709003)National Natural Science Foundation of China(NSFC)Top-level Project:Study on the Neuroimmunological Mechanism of Macrophage Phenotypic Polarisation for Antiinflammation Regulated by Acupuncture(No.81873369)+1 种基金National Natural Science Foundation of China Young Science Fund Project:Study on the Neuromodulation Mechanism of Electroacupuncture to Improve Neutropenia after Chemotherapy for Lung Cancer(No.81704146)National Natural Science Foundation of China Key Project:Research on the Initial Kinetic Regulation Mechanism of Acupuncture Effect Based on the Physicochemical Coupling Network of Acupuncture Point Microenvironment(No.82030125)。
文摘OBJECTIVE:To investigate the mechanisms behind the effects of acupuncture in Traditional Chinese Medicine,we delved into the adenosine triphosphate/peripheral purinergic P2X receptor 3(ATP/P2X3)receptor signaling system as an indicator of the body's energy state,commonly referred to as"Qi".METHODS:The tail-flick test was utilized to explore the impact of acupuncture on pain tolerance threshold(PTT)in mice,while also assessing adenosine(ADO)levels and adenylate energy charge(EC)at Zusanli(ST36).The study further investigated the dose-dependent effects of acupuncture on PTT and ADO levels at Zusanli(ST36).To shed light on the underlying mechanisms of acupuncture's effects,the study examined the impact of ATP,a P2X3 receptor antagonist,and adenosine disodium on PTT following acupuncture administration.RESULTS:Acupuncture at Zusanli(ST36)led to significant improvements in PTT in mice,with the most effective interventions being twirling for 2 min and needle retention for 28 min.These interventions also resulted in significant increases in ATP levels.The effects of acupuncture were further augmented by administration of different doses of ATP at Zusanli(ST36),and pretreatment with a P2X3 receptor antagonist decreased PTT.Adenylate EC peaked at 30 min after intraperitoneal injection of ATP,and pretreatment with various doses of i.p.ATP 30 min prior to acupuncture increased PTT in a dose-dependent manner.Additionally,pretreatment with an i.p.or intramuscular injection of adenosine disodium enhanced the effects of acupuncture.CONCLUSION:This research provides compelling evidence that ATP is involved in the regulation of PTT through acupuncture,revealing new avenues for achieving enhanced clinical outcomes.
基金supported by the National Natural Science Foundation of China,No.81273926,81573742the Natural Science Foundation of Zhejiang Province of China,No.LY15H290006
文摘The activation of adenosine A1 receptors is important for protecting against ischemic brain injury and pretreatment with electroacupuncture has been shown to mitigate ischemic brain insult. The aim of this study was to test whether the adenosine A1 receptor mediates electroacupuncture pretreatment-induced neuroprotection against ischemic brain injury. We first performed 30 minutes of electroacupuncture pretreatment at the Baihui acupoint(GV20), delivered with a current of 1 mA, a frequency of 2/15 Hz, and a depth of 1 mm. High-performance liquid chromatography found that adenosine triphosphate and adenosine levels peaked in the cerebral cortex at 15 minutes and 120 minutes after electroacupuncture pretreatment, respectively. We further examined the effect of 15 or 120 minutes electroacupuncture treatment on ischemic brain injury in a rat middle cerebral artery-occlusion model. We found that at 24 hours reperfusion,120 minutes after electroacupuncture pretreatment, but not for 15 minutes, significantly reduced behavioral deficits and infarct volumes. Last, we demonstrated that the protective effect gained by 120 minutes after electroacupuncture treatment before ischemic injury was abolished by pretreatment with the A1-receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine(1 mg/kg, intraperitoneally). Our results suggest that pretreatment with electroacupuncture at the Baihui acupoint elicits protection against transient cerebral ischemia via action at adenosine A1 receptors.
基金the National Natural Science Foundation of China, No.30670694 the Natural Science Foundation of Anhui Province Department of Education in China, No.2006KJ361B+2 种基金 the National Science Fund for Distinguished Young Scholars of Anhui Medical University, No.GJJQ-0801 the Scientific Research Foundation for Doctor of Anhui Medical University, No. XJ2005006the Special Foundation for Young Scientists in Higher Education Institutions of Anhui Province, No.2010SQRL078
文摘BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism of P2Rs in trigeminal neuralgia remains unclear. OBJECTIVE: To investigate changes in the P2R-mediated calcium signaling pathway in nociceptive trigemJnal ganglion neurons. DESIGN, TIME AND SETTING: In vitro experiments were conducted at the Patch-Clamp Laboratory of Comprehensive Experiment Center of Anhui Medical University, China from September 2008 to June 2009. MATERIALS: Thapsigargin, caffeine, suramin, and adenosine 5'-triphosphate were purchased from Sigma, USA. METHODS: Using Fura-2-based microfluorimetry, intracellular calcium concentration ([Ca^2+]i) was measured in freshly isolated adult rat small trigeminal ganglion neurons before and after drug application. MAIN OUTCOME MEASURES: Fluorescent intensities were expressed as the ratio F340/F380 to observe [Ca^2+]i changes. RESULTS: In normal extracellular solution and Ca^2+-free solution, application of thapsigargin (1 μmol/L), a sarcoplasmic reticulum Ca^2+ pump adenosine 5'-triphosphate inhibitor, as well as caffeine (20 mmol/L), a ryanodine receptor agonist, triggered [Ca^2+]i increase in small trigeminal ganglion neurons. A similar response was induced by application of adenosine 5'-triphosphate (100 μmol/L). In Ca^2+-free conditions, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were inhibited in cells pre-treated with thapsigargin (P 〈 0.01), but not by caffeine (P 〉 0.05). In normal, extracellular solution, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were partly inhibited in cells pre-treated with thapsigargin (P 〈 0.05). CONCLUSION: Inositol-1,4, 5-triphosphate (IP3)- and ryanodine-sensitive Ca^2+ stores exist in rat nociceptive trigeminal ganglion neurons. Two pathways are involved in the purinoreceptor-mediated [Ca^2+]i rise observed in nociceptive trigeminal ganglion neurons. One pathway involves the metabotropic P2Y receptors, which are associated with the IP3 sensitive Ca^2+store, and the second pathway is coupled to ionotropic P2X receptors that induce the Ca^2+ influx.
文摘目的本研究旨在建立一种实时荧光定量PCR方法,用于检测猕猴三磷酸腺苷结合盒转运蛋白G2(adenosine triphosphate-binding cassette transporter protein G2,ABCG2)mRNA的基因转录水平。方法使用NCBI上GenBank数据库猕猴(Macaca mulatta)的ABCG2核苷酸序列号NM_001032919.1及内参GAPDH核苷酸序列号NM_001195426.1,借助Primer premier 5.0软件设计PCR引物。提取猕猴新鲜肾组织的总RNA,并反转录合成cDNA。接着,利用PCR引物进行实时荧光定量PCR扩增,并根据反应体系中荧光的变化情况定量分析ABCG2的mRNA相对表达水平。结果PCR产物测序结果显示,扩增的ABCG2和GAPDH核苷酸序列与NCBI上猕猴的序列同源性分别为90.91%和91.14%。ABCG2和GAPDH的扩增效率均达到80%~120%,实时荧光定量PCR标准曲线的熔解曲线为单峰,R2接近1。结论本研究建立的检测猕猴ABCG2 mRNA实时荧光定量检测方法,为研究高尿酸血症的发病机制以及新药开发奠定基础。
文摘背景:阿尔茨海默病患者存在严重的脑能量障碍,近年来基于酮体干预的脑能量拯救策略在阿尔茨海默病的治疗中越来越受到重视。目的:探讨β-羟基丁酸能否改善β淀粉样蛋白1-42(β-amyloid protein 1-42,Aβ_(1-42))诱导的小鼠海马神经元HT22细胞能量障碍。方法:将HT22细胞分为4组,分别为对照组、β-羟基丁酸组、Aβ_(1-42)组、Aβ_(1-42)+β-羟基丁酸组。使用相应试剂盒检测HT22细胞的存活率、ATP水平、α-酮戊二酸脱氢酶活性、Na^(+)K^(+)-ATP酶活性、线粒体膜电位及活性氧水平。结果与结论:与对照组相比,Aβ_(1-42)组HT22细胞的存活率、ATP水平、α-酮戊二酸脱氢酶活性、Na^(+)K^(+)-ATP酶活性、线粒体膜电位均显著降低(P<0.05),活性氧水平显著升高(P<0.05)。与Aβ_(1-42)组相比,Aβ_(1-42)+β-羟基丁酸组HT22细胞的存活率、ATP水平、α-酮戊二酸脱氢酶活性、Na^(+)K^(+)-ATP酶活性、线粒体膜电位均显著升高(P<0.05),活性氧水平显著降低(P<0.05)。结果表明:β-羟基丁酸提高了线粒体生物能量功能和细胞存活率,最终改善了Aβ_(1-42)诱导的HT22细胞能量障碍。