3-bromo-4,5-bis（2,3-dibromo-4,5-dihydroxybenzyl）-l,2-benzenediol （1） is a natural bromophenol isolated from the red algae Rhodomela confervoides that exhibits significant inhibition against protein tyrosine phosph...3-bromo-4,5-bis（2,3-dibromo-4,5-dihydroxybenzyl）-l,2-benzenediol （1） is a natural bromophenol isolated from the red algae Rhodomela confervoides that exhibits significant inhibition against protein tyrosine phosphatase 1B （PTP1B）. Based on its activity, we synthesized two new synthetic bromophenols and their methoxy derivatives from vanillin using the structure of natural bromophenol 1 as a scaffold. The structures of these bromophenols were elucidated from H NMR, 13C NMR, and high resolution electron ionization mass spectrometry as 2,3-dibromo-1-（2＇-bromo-6＇-（3＂,4＂-dimethoxybenzyl）- 3 ＇,4 ＇-dimethoxybenzyl）-4,5 -dimethoxybenzene （2）, 2,3-dibromo- 1 -（2 ＇-bromo-6＇-（2 ＂-bromo-4＂,5 ＂-dimethoxy- benzyl）-3＇,4＇-dimethoxybenzyl）-4,5-dimethoxybenzene （3）, 3,4-dibromo-5-（2＇-bromo-6＇-（2＂-bromo-4＂,5＂- dihydroxybenzyl）-3＇,4＇-dihydroxybenzyl）pyrocatechol （4） and 3,4-dibromo-5-（2＇-bromo-6＇-（3＂,4＂- dihydroxybenzyl）-3＇,4＇-dihydroxybenzyl）pyrocatechol （5）. PTP1B inhibition activities of these compounds were evaluated using a colorimetric assay, and compounds 3 and 4 demonstrated interesting activity against PTP1B.展开更多
We intraperitoneally injected 10 and 50 mg/kg of propofol for 7 consecutive days to treat a rat model of chronic cerebral ischemia. A low-dose of propofol promoted the expression of brain-derived neurotrophic factor, ...We intraperitoneally injected 10 and 50 mg/kg of propofol for 7 consecutive days to treat a rat model of chronic cerebral ischemia. A low-dose of propofol promoted the expression of brain-derived neurotrophic factor, tyrosine kinase receptor B, phosphorylated cAMP response element binding protein, and cAMP in the hippocampus of aged rats with chronic cerebral ischemia, but a high-dose of propofol inhibited their expression. Results indicated that the protective effect of propofol against cerebral ischemia in aged rats is related to changes in the expression of brain-derived neurotrophic factor and tyrosine kinase receptor B in the hippocampus, and that the cAMP-cAMP responsive element binding protein pathway is involved in the regulatory effect of propofol on brain-derived neurotrophic factor expression.展开更多
BACKGROUND： There are a limited number of studies involving the effects of ginsenosides, the active component of ginseng, on expression of hippocampal TrkB mRNA in aged rats. OBJECTIVE： To observe expression of brai...BACKGROUND： There are a limited number of studies involving the effects of ginsenosides, the active component of ginseng, on expression of hippocampal TrkB mRNA in aged rats. OBJECTIVE： To observe expression of brain-derived neurotrophic factor （BDNF） and tyrosine kinase B （TrkB） mRNA in the hippocampal formation of aged rats, as well as changes after ginsenoside administrated. DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed at the Department of Anatomy, College of Basic Medical Sciences, China Medical University in March 2005. MATERIALS： A total of 39 female, Wistar rats were randomly divided into 3 groups （n = 13 each）： young （3-5 months old）, aged （27 months old）, and ginsenoside group （received 25mg/kg/d ginsenoside in the drinking water between 17 and 27 months of age）. METHODS： Following anesthesia, the rats were exsanguinated and perfused transcardially with chilled, heparinized, 0.9% saline. The brains were removed and post-fixed in 40 g/L paraformaldehyde/phosphate buffer for 20 minutes, and further incubated in 30% sucrose/phosphate buffer overnight. MAIN OUTCOME MEASURES： In situ hybridization, immunohistochemistry, and image analysis were used to investigate expression of BDNF and TrkB mRNA in the hippocampal formation. RESULTS： The expression levels of BDNF in the hippocampal CA3 and CA1 of aged rats was significantly less than the young group （t = 2.879, 1.814, 1.984, P 〈 0.05）. BDNF expression was significantly greater in the dentate gyrus of the ginsenoside group, compared with the aging group （t = 1.943, P 〈 0.01）. The expression of TrkB mRNA in the hippocampal CA3, CA1, and dentate gyrus of aged rats was less than the young group （t = 3.540, 3.629, 17.905, P 〈 0.01）. TrkB mRNA expression in the CA3 region and dentate gyrus of the ginsenoside group was significantly greater compared with the aging group （t = 1.293, 3.386, P 〈 0.05, 0.01 ）. CONCLUSION： BDNF and TrkB mRNA expression in the hippocampal formation were reduced in the aged group. However, ginsenosides can increase BDNF and TrkB mRNA expression in the hippocampal formation.展开更多
Since in most tumors multiple signaling pathways are involved,many of the inhibitors in clinical development are designed to affect a wide range of targeted kinases.The most important tyrosine kinase families in the d...Since in most tumors multiple signaling pathways are involved,many of the inhibitors in clinical development are designed to affect a wide range of targeted kinases.The most important tyrosine kinase families in the development of tyrosine kinase inhibitors are the ABL,SCR,platelet derived growth factor,vascular endothelial growth factor receptor and epidermal growth factor receptor families.Both multi-kinase inhibitors and singlekinase inhibitors have advantages and disadvantages,which are related to potential resistance mechanisms,pharmacokinetics,selectivity and tumor environment.In different malignancies various tyrosine kinases are mutated or overexpressed and several resistance mechanisms exist.Pharmacokinetics is influenced by interindividual differences and differs for two single targeted inhibitors or between patients treated by the same tyrosine kinase inhibitor.Different tyrosine kinase inhibitors have various mechanisms to achieve selectivity,while differences in gene expression exist between tumor and stromal cells.Considering these aspects,one type of inhibitor can generally not be preferred above the other,but will depend on the specific genetic constitution of the patient and the tumor,allowing personalized therapy.The most effective way of cancer treatment by using tyrosine kinase inhibitors is to consider each patient/tumor individually and to determine the strategy that specifically targets the consequences of altered(epi)genetics of the tumor.This strategy might result in treatment by a single multi kinase inhibitor for one patient,but in treatment by a couple of single kinase inhibitors for other patients.展开更多
Tyrosine kinase receptor B （TrkB） plays an important role in long-term potentiation and memory formation.The present study used all-trans retinoic acid to induce TrkB expression in SH-SY5Y cells,and observed the eff...Tyrosine kinase receptor B （TrkB） plays an important role in long-term potentiation and memory formation.The present study used all-trans retinoic acid to induce TrkB expression in SH-SY5Y cells,and observed the effects of levetiracetam （LEV） on TrkB expression.Following exposure to 10,50,and 100 μg/mL LEV,the number of TrkB-positive cells,and average absorbance value were increased.Results demonstrated that LEV can induce TrkB expression in SH-SY5Y cells.展开更多
According to LN?,theoretical&true elongation of tensile,and by adopting the increasing function of formulas with the derivation and analogy methods,the elongation formula of 0<(1+ε)^1/ε<e&0<ε^1/ε&...According to LN?,theoretical&true elongation of tensile,and by adopting the increasing function of formulas with the derivation and analogy methods,the elongation formula of 0<(1+ε)^1/ε<e&0<ε^1/ε<1&four convergences are deduced too whenε>1 and 0<ε<1.The inequalities of LNε<εand LN(1+ε)<εand LN(1+ε)>LNεare deduced ifε>1 and 0<ε<1 in material dynamics.Finally the conclusions of LNε<εand LNε<LN(1+ε)<εare deduced together ifε>1 and 0<ε<1.展开更多
目的研究百会穴久留针法通过脑源性神经营养因子(BDNF)/酪氨酸受体激酶B(TrkB)通路改善缺血性脑卒中小鼠神经功能的作用及机制。方法选择雄性C57BL/6J小鼠48只,随机分为假手术1组、模型1组、久留针1组、普通留针组,每组12只。后3组采用...目的研究百会穴久留针法通过脑源性神经营养因子(BDNF)/酪氨酸受体激酶B(TrkB)通路改善缺血性脑卒中小鼠神经功能的作用及机制。方法选择雄性C57BL/6J小鼠48只,随机分为假手术1组、模型1组、久留针1组、普通留针组,每组12只。后3组采用线栓法制备缺血性脑卒中模型,手术造模后第1天起久留针1组和普通留针组分别给予百会穴久留针和普通留针治疗,连续14 d。另选择雄性C57BL/6J小鼠40只,随机分为假手术2组、模型2组、久留针2组、久留针3组,每组10只。后3组采用线栓法制备缺血性脑卒中模型,针灸治疗前分别给予腺相关病毒100μl单次尾静脉注射。采用改良神经功能缺损评分(mNSS)及水迷宫实验的逃避潜伏期、目标象限停留时间、穿越原平台次数评价神经功能。结果与假手术1组比较,模型1组mNSS评分、目标象限停留时间、穿越原平台次数及缺血脑组织BDNF、TrkB表达明显降低,细胞凋亡率及裂解型半胱氨酸天冬氨酸蛋白酶3(Caspase-3)表达明显增加,差异有统计学意义(P<0.05);与模型1组比较,久留针1组和普通留针组mNSS评分、目标象限停留时间、穿越原平台次数及缺血脑组织BDNF、TrkB表达明显增加,细胞凋亡率及裂解型Caspase-3表达明显降低,且久留针1组上述变化较普通留针组更为显著,差异有统计学意义(P<0.05)。与久留针2组比较,久留针3组mNSS评分、目标象限停留时间、穿越原平台次数及缺血脑组织中BDNF表达明显降低(P<0.05),细胞凋亡率及裂解型Caspase-3表达明显增加[(16.41±2.25)%vs(7.59±1.09)%;1.46±0.16 vs 0.94±0.12,P<0.05]。结论百会穴久留针治疗对缺血性脑卒中小鼠神经功能的改善作用更为显著,激活BDNF/TrkB通路是其发挥神经保护作用的相关分子机制。展开更多
Colorectal cancer(CRC) is the second most common cause of cancer-related death in western countries. Approximately one-quarter of newly diagnosed patients for CRC have metastases, and a further 40%-50% experience dise...Colorectal cancer(CRC) is the second most common cause of cancer-related death in western countries. Approximately one-quarter of newly diagnosed patients for CRC have metastases, and a further 40%-50% experience disease recurrence or develop metastases after all standard therapies. Therefore, understanding the molecular mechanisms involved in the progression of CRC and subsequently developing novel therapeutic targets is crucial to improve management of CRC and patients' long-term survival. Several tyrosine kinase receptors have been implicated in CRC development, progression and metastasis, including epidermal growth factor receptor(EGFR) and vascular EGFR. Recently, tropomyosin-related kinase B(Trk B), a tyrosine kinase receptor, has been reported in CRC and found to clearly exert several biological and clinical features, such as tumor cell growth and survival in vitro and in vivo, metastasis formation and poor prognosis. Here we review the significance of Trk B and its ligand brain derived-neurotrophic factor in CRC. We focus on their expression in CRC tumor samples, and their functional roles in CRC cell lines and in in vivo models. Finally we discuss therapeutic approaches that can lead to the development of novel therapeutic agents for treating Trk B-expressing CRC tumors.展开更多
Previous studies showed that tyrosine hydroxylase or neurturin gene-modified cells transplanted into rats with Parkinson＇s disease significantly improved behavior and increased striatal dopamine content. In the prese...Previous studies showed that tyrosine hydroxylase or neurturin gene-modified cells transplanted into rats with Parkinson＇s disease significantly improved behavior and increased striatal dopamine content. In the present study, we transplanted tyrosine hydroxylase and neurturin gene-modified bone marrow-derived mesenchymal stem cells into the damaged striatum of Parkinson＇s disease model rats. Several weeks after cell transplantation, in addition to an improvement of motor function tyrosine hydroxylase and neurturin proteins were up-regulated in the injured striatum, and importantly, levels of dopamine and its metabolite 3,4-dihydroxyphenylacetic acid increased significantly. Furthermore, the density of the D2 dopamine receptor in the postsynaptic membranes of dopaminergic neurons was decreased. These results indicate that transplantation of tyrosine hydroxylase and neurturin gene-modified bone marrow-derived mesenchymal stem cells increases dopamine synthesis and significantly improves the behavior of rats with Parkinson＇s disease.展开更多
基金Supported by the National Major Research Program of China"The Creation for Significant Innovative Drugs"(No.2009ZX09103-148)the Natural Science Foundation of Shandong(No.BS2009YY011)+1 种基金the Natural Science Foundation of Qingdao(No.10-3-4-8-2-JCH)the Program of Qingdao Shinan District(No.2009-HY-2-14)
文摘3-bromo-4,5-bis（2,3-dibromo-4,5-dihydroxybenzyl）-l,2-benzenediol （1） is a natural bromophenol isolated from the red algae Rhodomela confervoides that exhibits significant inhibition against protein tyrosine phosphatase 1B （PTP1B）. Based on its activity, we synthesized two new synthetic bromophenols and their methoxy derivatives from vanillin using the structure of natural bromophenol 1 as a scaffold. The structures of these bromophenols were elucidated from H NMR, 13C NMR, and high resolution electron ionization mass spectrometry as 2,3-dibromo-1-（2＇-bromo-6＇-（3＂,4＂-dimethoxybenzyl）- 3 ＇,4 ＇-dimethoxybenzyl）-4,5 -dimethoxybenzene （2）, 2,3-dibromo- 1 -（2 ＇-bromo-6＇-（2 ＂-bromo-4＂,5 ＂-dimethoxy- benzyl）-3＇,4＇-dimethoxybenzyl）-4,5-dimethoxybenzene （3）, 3,4-dibromo-5-（2＇-bromo-6＇-（2＂-bromo-4＂,5＂- dihydroxybenzyl）-3＇,4＇-dihydroxybenzyl）pyrocatechol （4） and 3,4-dibromo-5-（2＇-bromo-6＇-（3＂,4＂- dihydroxybenzyl）-3＇,4＇-dihydroxybenzyl）pyrocatechol （5）. PTP1B inhibition activities of these compounds were evaluated using a colorimetric assay, and compounds 3 and 4 demonstrated interesting activity against PTP1B.
基金supported by the National Natural Science Foundation of China (GABA receptor mechanism ofpropofol to promote neural regeneration), No. 30571791
文摘We intraperitoneally injected 10 and 50 mg/kg of propofol for 7 consecutive days to treat a rat model of chronic cerebral ischemia. A low-dose of propofol promoted the expression of brain-derived neurotrophic factor, tyrosine kinase receptor B, phosphorylated cAMP response element binding protein, and cAMP in the hippocampus of aged rats with chronic cerebral ischemia, but a high-dose of propofol inhibited their expression. Results indicated that the protective effect of propofol against cerebral ischemia in aged rats is related to changes in the expression of brain-derived neurotrophic factor and tyrosine kinase receptor B in the hippocampus, and that the cAMP-cAMP responsive element binding protein pathway is involved in the regulatory effect of propofol on brain-derived neurotrophic factor expression.
文摘BACKGROUND： There are a limited number of studies involving the effects of ginsenosides, the active component of ginseng, on expression of hippocampal TrkB mRNA in aged rats. OBJECTIVE： To observe expression of brain-derived neurotrophic factor （BDNF） and tyrosine kinase B （TrkB） mRNA in the hippocampal formation of aged rats, as well as changes after ginsenoside administrated. DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed at the Department of Anatomy, College of Basic Medical Sciences, China Medical University in March 2005. MATERIALS： A total of 39 female, Wistar rats were randomly divided into 3 groups （n = 13 each）： young （3-5 months old）, aged （27 months old）, and ginsenoside group （received 25mg/kg/d ginsenoside in the drinking water between 17 and 27 months of age）. METHODS： Following anesthesia, the rats were exsanguinated and perfused transcardially with chilled, heparinized, 0.9% saline. The brains were removed and post-fixed in 40 g/L paraformaldehyde/phosphate buffer for 20 minutes, and further incubated in 30% sucrose/phosphate buffer overnight. MAIN OUTCOME MEASURES： In situ hybridization, immunohistochemistry, and image analysis were used to investigate expression of BDNF and TrkB mRNA in the hippocampal formation. RESULTS： The expression levels of BDNF in the hippocampal CA3 and CA1 of aged rats was significantly less than the young group （t = 2.879, 1.814, 1.984, P 〈 0.05）. BDNF expression was significantly greater in the dentate gyrus of the ginsenoside group, compared with the aging group （t = 1.943, P 〈 0.01）. The expression of TrkB mRNA in the hippocampal CA3, CA1, and dentate gyrus of aged rats was less than the young group （t = 3.540, 3.629, 17.905, P 〈 0.01）. TrkB mRNA expression in the CA3 region and dentate gyrus of the ginsenoside group was significantly greater compared with the aging group （t = 1.293, 3.386, P 〈 0.05, 0.01 ）. CONCLUSION： BDNF and TrkB mRNA expression in the hippocampal formation were reduced in the aged group. However, ginsenosides can increase BDNF and TrkB mRNA expression in the hippocampal formation.
文摘Since in most tumors multiple signaling pathways are involved,many of the inhibitors in clinical development are designed to affect a wide range of targeted kinases.The most important tyrosine kinase families in the development of tyrosine kinase inhibitors are the ABL,SCR,platelet derived growth factor,vascular endothelial growth factor receptor and epidermal growth factor receptor families.Both multi-kinase inhibitors and singlekinase inhibitors have advantages and disadvantages,which are related to potential resistance mechanisms,pharmacokinetics,selectivity and tumor environment.In different malignancies various tyrosine kinases are mutated or overexpressed and several resistance mechanisms exist.Pharmacokinetics is influenced by interindividual differences and differs for two single targeted inhibitors or between patients treated by the same tyrosine kinase inhibitor.Different tyrosine kinase inhibitors have various mechanisms to achieve selectivity,while differences in gene expression exist between tumor and stromal cells.Considering these aspects,one type of inhibitor can generally not be preferred above the other,but will depend on the specific genetic constitution of the patient and the tumor,allowing personalized therapy.The most effective way of cancer treatment by using tyrosine kinase inhibitors is to consider each patient/tumor individually and to determine the strategy that specifically targets the consequences of altered(epi)genetics of the tumor.This strategy might result in treatment by a single multi kinase inhibitor for one patient,but in treatment by a couple of single kinase inhibitors for other patients.
文摘Tyrosine kinase receptor B （TrkB） plays an important role in long-term potentiation and memory formation.The present study used all-trans retinoic acid to induce TrkB expression in SH-SY5Y cells,and observed the effects of levetiracetam （LEV） on TrkB expression.Following exposure to 10,50,and 100 μg/mL LEV,the number of TrkB-positive cells,and average absorbance value were increased.Results demonstrated that LEV can induce TrkB expression in SH-SY5Y cells.
基金KNRF(the Korea of National Research Foundation)under the Specified base program 96-0300-11-01-3.
文摘According to LN?,theoretical&true elongation of tensile,and by adopting the increasing function of formulas with the derivation and analogy methods,the elongation formula of 0<(1+ε)^1/ε<e&0<ε^1/ε<1&four convergences are deduced too whenε>1 and 0<ε<1.The inequalities of LNε<εand LN(1+ε)<εand LN(1+ε)>LNεare deduced ifε>1 and 0<ε<1 in material dynamics.Finally the conclusions of LNε<εand LNε<LN(1+ε)<εare deduced together ifε>1 and 0<ε<1.
文摘目的研究百会穴久留针法通过脑源性神经营养因子(BDNF)/酪氨酸受体激酶B(TrkB)通路改善缺血性脑卒中小鼠神经功能的作用及机制。方法选择雄性C57BL/6J小鼠48只,随机分为假手术1组、模型1组、久留针1组、普通留针组,每组12只。后3组采用线栓法制备缺血性脑卒中模型,手术造模后第1天起久留针1组和普通留针组分别给予百会穴久留针和普通留针治疗,连续14 d。另选择雄性C57BL/6J小鼠40只,随机分为假手术2组、模型2组、久留针2组、久留针3组,每组10只。后3组采用线栓法制备缺血性脑卒中模型,针灸治疗前分别给予腺相关病毒100μl单次尾静脉注射。采用改良神经功能缺损评分(mNSS)及水迷宫实验的逃避潜伏期、目标象限停留时间、穿越原平台次数评价神经功能。结果与假手术1组比较,模型1组mNSS评分、目标象限停留时间、穿越原平台次数及缺血脑组织BDNF、TrkB表达明显降低,细胞凋亡率及裂解型半胱氨酸天冬氨酸蛋白酶3(Caspase-3)表达明显增加,差异有统计学意义(P<0.05);与模型1组比较,久留针1组和普通留针组mNSS评分、目标象限停留时间、穿越原平台次数及缺血脑组织BDNF、TrkB表达明显增加,细胞凋亡率及裂解型Caspase-3表达明显降低,且久留针1组上述变化较普通留针组更为显著,差异有统计学意义(P<0.05)。与久留针2组比较,久留针3组mNSS评分、目标象限停留时间、穿越原平台次数及缺血脑组织中BDNF表达明显降低(P<0.05),细胞凋亡率及裂解型Caspase-3表达明显增加[(16.41±2.25)%vs(7.59±1.09)%;1.46±0.16 vs 0.94±0.12,P<0.05]。结论百会穴久留针治疗对缺血性脑卒中小鼠神经功能的改善作用更为显著,激活BDNF/TrkB通路是其发挥神经保护作用的相关分子机制。
基金Supported by Conseil Régional du Limousin and the CORC ComitéOrientation Recherche Cancer
文摘Colorectal cancer(CRC) is the second most common cause of cancer-related death in western countries. Approximately one-quarter of newly diagnosed patients for CRC have metastases, and a further 40%-50% experience disease recurrence or develop metastases after all standard therapies. Therefore, understanding the molecular mechanisms involved in the progression of CRC and subsequently developing novel therapeutic targets is crucial to improve management of CRC and patients' long-term survival. Several tyrosine kinase receptors have been implicated in CRC development, progression and metastasis, including epidermal growth factor receptor(EGFR) and vascular EGFR. Recently, tropomyosin-related kinase B(Trk B), a tyrosine kinase receptor, has been reported in CRC and found to clearly exert several biological and clinical features, such as tumor cell growth and survival in vitro and in vivo, metastasis formation and poor prognosis. Here we review the significance of Trk B and its ligand brain derived-neurotrophic factor in CRC. We focus on their expression in CRC tumor samples, and their functional roles in CRC cell lines and in in vivo models. Finally we discuss therapeutic approaches that can lead to the development of novel therapeutic agents for treating Trk B-expressing CRC tumors.
基金supported by grants from the Ministryof Health of China, No. 2011010009the Science and Technology Department of Henan Province, No.112102310230
文摘Previous studies showed that tyrosine hydroxylase or neurturin gene-modified cells transplanted into rats with Parkinson＇s disease significantly improved behavior and increased striatal dopamine content. In the present study, we transplanted tyrosine hydroxylase and neurturin gene-modified bone marrow-derived mesenchymal stem cells into the damaged striatum of Parkinson＇s disease model rats. Several weeks after cell transplantation, in addition to an improvement of motor function tyrosine hydroxylase and neurturin proteins were up-regulated in the injured striatum, and importantly, levels of dopamine and its metabolite 3,4-dihydroxyphenylacetic acid increased significantly. Furthermore, the density of the D2 dopamine receptor in the postsynaptic membranes of dopaminergic neurons was decreased. These results indicate that transplantation of tyrosine hydroxylase and neurturin gene-modified bone marrow-derived mesenchymal stem cells increases dopamine synthesis and significantly improves the behavior of rats with Parkinson＇s disease.
