AIM To investigate the role of calmodulin-dependent protein kinase Ⅱ(Ca MKⅡ) in colon cancer growth,migration and invasion.METHODS Ca MKⅡ expression in colon cancer and paracancerous tissues was evaluated via immun...AIM To investigate the role of calmodulin-dependent protein kinase Ⅱ(Ca MKⅡ) in colon cancer growth,migration and invasion.METHODS Ca MKⅡ expression in colon cancer and paracancerous tissues was evaluated via immunochemistry. Transcriptional and posttranscriptional levels of Ca MKⅡin tissue samples and MMP2,MMP9 and TIMP-1 expression in the human colon cancer cell line HCT116 were assessed by q RTPCR and western blot. Cell proliferation was detected with the MTT assay. Cancer cell migration and invasion were investigated with the Transwell culture system and woundhealing assay.RESULTS We first demonstrated that CaMK Ⅱ was ove rexpressed in human colon cancers and was associated with cancer differentiation. In the human colon cancer cell line HCT116,the Ca MKII-specific inhibitor KN93,but not its inactive analogue KN92,decreased cancer cell proliferation. Furthermore,KN93 also significantly prohibited HCT116 cell migration and invasion. The specific inhibition of ERK1/2 or p38 decreased the proliferation and migration of colon cancer cells.CONCLUSION Our findings highlight Ca MKⅡ as a potential critical mediator in human colon tumor development and metastasis.展开更多
In this study, primary cultured cerebral cortical neurons of Sprague-Dawley neonatal rats were treated with 0.25, 0.5, and 1.0 μM calmodulin-dependent protein kinase II inhibitor KN-93 after 50 μM N-methyI-D-asparti...In this study, primary cultured cerebral cortical neurons of Sprague-Dawley neonatal rats were treated with 0.25, 0.5, and 1.0 μM calmodulin-dependent protein kinase II inhibitor KN-93 after 50 μM N-methyI-D-aspartic acid-induced injury. Results showed that, compared with N-methyi-D- aspartic acid-induced injury neurons, the activity of cells markedly increased, apoptosis was significantly reduced, leakage of lactate dehydrogenase decreased, and intracellular Ca2＋ concentrations in neurons reduced after KN-93 treatment. The expression of caspase-3, phosphorylated calmodulin-dependent protein kinase II and total calmodulin-dependent protein kinase II protein decreased after KN-93 treatment. And the effect was apparent at a dose of 1.0 pM KN-93. Experimental findings suggest that KN-93 can induce a dose-dependent neuroprotective effect, and that the underlying mechanism may be related to the down-regulation of caspase-3 and calmodulin- dependent protein kinase II expression.展开更多
Metabolic syndrome is a pre-diabetic state characterized by several biochemical and physiological alterations,including insulin resistance,visceral fat accumulation,and dyslipidemias,which increase the risk for develo...Metabolic syndrome is a pre-diabetic state characterized by several biochemical and physiological alterations,including insulin resistance,visceral fat accumulation,and dyslipidemias,which increase the risk for developing cardiovascular disease.Metabolic syndrome is associated with augmented sympathetic tone,which could account for the etiology of pre-diabetic cardiomyopathy.This review summarizes the current knowledge of the pathophysiological consequences of enhanced and sustainedβ-adrenergic response in pre-diabetes,focusing on cardiac dysfunction reported in diet-induced experimental models of pre-diabetic cardiomyopathy.The research reviewed indicates that both protein kinase A and Ca^(2+)/calmodulin-dependent protein kinase Ⅱ play important roles in functional responses mediated byβ1-adrenoceptors;therefore,alterations in the expression or function of these kinases can be deleterious.This review also outlines recent information on the role of protein kinase A and Ca^(2+)/calmodulin-dependent protein kinase Ⅱ in abnormal Ca^(2+)handling by cardiomyocytes from diet-induced models of pre-diabetic cardiomyopathy.展开更多
Using nystatin-perforated whole-cell recording configuration, the modulatory effect of N-methyl-D-aspartate (NMDA) on γ-aminobutyric acid (GABA)-activated whole-cell currents was investigated in neurons freshly disso...Using nystatin-perforated whole-cell recording configuration, the modulatory effect of N-methyl-D-aspartate (NMDA) on γ-aminobutyric acid (GABA)-activated whole-cell currents was investigated in neurons freshly dissociated from the rat sacral dorsal commissural nucleus (SDCN). The results showed that: (i) NMDA suppressed GABA- and muscimol (Mus)-activated currents (IGABA and IMUS), respectively in the Mg2+-free external solution containing 1 μmol/L glycine at a holding potential (VH) of -40 mV in SDCN neurons. The selective NMDA receptor antagonist, D-2-amino-5-phosphonovaleric acid (APV, 100 μmol/L), inhibited the NMDA-evoked currents and blocked the NMDA-induced suppression of IGABA; (ii) when the neurons were incubated in a Ca2+-free bath or pre-loaded with a membrane-permeable Ca2+ chelator, BAPTA AM (10 nmol/L), the inhibitory effect of NMDA on IGABA disappeared. Cd2+ (10 μmol/L) or La3+(30 μmol/L), the non-selective blockers of voltage-dependent calcium channels, did not affect the suppression of IGABA by NMDA application; (iii) the suppression of IGABA by NMDA was inhibited by KN-62, a cal-cium/calmodulin-dependent protein kinase II (CaMKII) inhibitor. These results indicated that the inhibition of GABA response by NMDA is Ca2+-dependent and CaMKII is involved in the process of the Ca2+-dependent inhibition.展开更多
Aim In diabetic patients, metformin appears to provide cardiovascular protection that cannot be attribu- ted only to its antihyperglycemic effects. Metformin is also known as the AMP-activated protein kinase （AMPK） ...Aim In diabetic patients, metformin appears to provide cardiovascular protection that cannot be attribu- ted only to its antihyperglycemic effects. Metformin is also known as the AMP-activated protein kinase （AMPK） ac- tivator. Our previous study suggested that metformin inhibits transforming growth factor-β1 （TGF-β1） production in a mouse heart failure model of pressure overload. TGF-β1 is a key factor in cardiac fibrosis and is usually induced by Angiotensin Ⅱ （Ang Ⅱ ） in the pressure overload mouse models. This study investigated the effect of metformin on cardiac fibrosis and TGF-β production induced by AngII and the underlying mechanisms. Methods C57/BL6 wild-type and AMPKα2 knockout mice were used. AngII （3 mg · kg-1 · d-1） was infused subcutaneously into mice for 7 days. Adult mouse cardiac fibroblasts were isolated and treated with AngII （ 1 μmol · L-1） and/or met- formin （1 mmol · L-l）. Results In C57/BL6 mice, metformin inhibits AngII-induced cardiac fibrosis. In cardi-ac fibroblasts, metformin inhibits TGF-β1 expression and production induced by AngII. AMPK inhibitor, com- pound C, reversed the effects of metformin. In vivo, AMPKα2 deficiency further increases AngII-induced TGF-β1 production. In cardiac fibroblasts, metformin inhibited AngII induced hepatocyte nuclear factor4 （HNF4ot protein level increase and HNF4α binding with TGF-β1 promoter using chromatin immunoprecipitation assay. In vivo, AMPKα2 deficiency further increased AngII-induced HNF4α protein level. Using HNF4α adenovirus, overexpress- ing HNF4α led to a 1.5-fold increase in TGF-β1 mRNA expression. HNF4a siRNA blocked AngII induced TGF- β1 production. Luciferase reporter with deleted HNF4a binding sites showed decreased TGFbl transcriptional activ- ity induced by AngII. In AMPK or2-/- heart, the inhibition of metformin on HNF4a protein was attenuated. Con- clusion Metformin inhibits AngII induced cardiac fibrosis and TGF-β1 production through AMPK activation. The underlying mechanism is that AMPK activation inhibits AngII induced HNF4α and then decreases TGF-β1 expres- sion.展开更多
Inositol polyphosphate-4-phosphatase type II(INPP4B)is a newly discovered PI(3,4,5)P3 phosphatase.Many studies have revealed that INPP4B is upregulated or downregulated in tumors of the digestive system,and the abnorm...Inositol polyphosphate-4-phosphatase type II(INPP4B)is a newly discovered PI(3,4,5)P3 phosphatase.Many studies have revealed that INPP4B is upregulated or downregulated in tumors of the digestive system,and the abnormal expression of INPP4B may be attributed to the occurrence,development,and prognosis of tumors of the digestive system.This paper reviews studies on the correlations between INPP4B and digestive system tumors and the roles of INPP4B in the development of different tumors to provide a theoretical basis for further research on its molecular mechanism and clinical application."INPP4B"and"tumor"were searched as key words in PubMed and in the CNKI series full text database retrieval system from January 2000 to August 2023.A total of 153 Englishlanguage studies and 30 Chinese-language studies were retrieved.The following enrollment criteria were applied:(1)Studies contained information on the biological structure and functions of INPP4B;(2)studies covered the influence of abnormal expression of INPP4B in digestive system tumors;and(3)studies covered the role of INPP4B in the diagnosis,treatment,and prognosis of digestive system tumors.After excluding the literature irrelevant to this study,61 papers were finally included in the analysis.INPP4B expression is low in gastric cancer,colon cancer,pancreatic cancer,and liver cancer but it has high expression in esophageal cancer,colon cancer,pancreatic cancer,and gallbladder cancer.INPP4B is involved in the occurrence and development of digestive system tumors through the regulation of gene expression and signal transduction.The abnormal expression of INPP4B plays an important role in the development of digestive system tumors.Studies on INPP4B provide new molecular insights for the diagnosis,treatment,and prognosis evaluation of digestive system tumors.展开更多
Protein kinase CK2 consists of two catalytic subunits (CK2α) and two regulatory subunits (CK2β). Here, we report the crystal structures of rat CK2α mutant (rCK2α-△C, 1—335) and CK2β (rCK2β). The overall topolo...Protein kinase CK2 consists of two catalytic subunits (CK2α) and two regulatory subunits (CK2β). Here, we report the crystal structures of rat CK2α mutant (rCK2α-△C, 1—335) and CK2β (rCK2β). The overall topology of rCK2α-△C and rCK2β are very similar to the human enzyme, although large structural differences could be observed in the N-terminal domain of rCK2α-△C. Our reported structure of rCK2α-△C is in the close conformation state while the counterpart hCK2α is in the open conformation state, indi- cating the conformation of CK2α molecule has high plasticity. The structure of rCK2β represents the conformation of free CK2β. Upon CK2α binding, the C-terminal region undergoes a drastic conformational change. The major region of interaction within the interface of CK2α/CK2β may serve as a bridge to transmit the conformational change and thus regulate the activity of CK2α.展开更多
基金Supported by the National Natural Science Foundation of China,No.81302131
文摘AIM To investigate the role of calmodulin-dependent protein kinase Ⅱ(Ca MKⅡ) in colon cancer growth,migration and invasion.METHODS Ca MKⅡ expression in colon cancer and paracancerous tissues was evaluated via immunochemistry. Transcriptional and posttranscriptional levels of Ca MKⅡin tissue samples and MMP2,MMP9 and TIMP-1 expression in the human colon cancer cell line HCT116 were assessed by q RTPCR and western blot. Cell proliferation was detected with the MTT assay. Cancer cell migration and invasion were investigated with the Transwell culture system and woundhealing assay.RESULTS We first demonstrated that CaMK Ⅱ was ove rexpressed in human colon cancers and was associated with cancer differentiation. In the human colon cancer cell line HCT116,the Ca MKII-specific inhibitor KN93,but not its inactive analogue KN92,decreased cancer cell proliferation. Furthermore,KN93 also significantly prohibited HCT116 cell migration and invasion. The specific inhibition of ERK1/2 or p38 decreased the proliferation and migration of colon cancer cells.CONCLUSION Our findings highlight Ca MKⅡ as a potential critical mediator in human colon tumor development and metastasis.
基金supported by Liaoning Social Development Key Projects of Scientific and Technological Department of Liaoning Province, No. 2012225019
文摘In this study, primary cultured cerebral cortical neurons of Sprague-Dawley neonatal rats were treated with 0.25, 0.5, and 1.0 μM calmodulin-dependent protein kinase II inhibitor KN-93 after 50 μM N-methyI-D-aspartic acid-induced injury. Results showed that, compared with N-methyi-D- aspartic acid-induced injury neurons, the activity of cells markedly increased, apoptosis was significantly reduced, leakage of lactate dehydrogenase decreased, and intracellular Ca2＋ concentrations in neurons reduced after KN-93 treatment. The expression of caspase-3, phosphorylated calmodulin-dependent protein kinase II and total calmodulin-dependent protein kinase II protein decreased after KN-93 treatment. And the effect was apparent at a dose of 1.0 pM KN-93. Experimental findings suggest that KN-93 can induce a dose-dependent neuroprotective effect, and that the underlying mechanism may be related to the down-regulation of caspase-3 and calmodulin- dependent protein kinase II expression.
文摘Metabolic syndrome is a pre-diabetic state characterized by several biochemical and physiological alterations,including insulin resistance,visceral fat accumulation,and dyslipidemias,which increase the risk for developing cardiovascular disease.Metabolic syndrome is associated with augmented sympathetic tone,which could account for the etiology of pre-diabetic cardiomyopathy.This review summarizes the current knowledge of the pathophysiological consequences of enhanced and sustainedβ-adrenergic response in pre-diabetes,focusing on cardiac dysfunction reported in diet-induced experimental models of pre-diabetic cardiomyopathy.The research reviewed indicates that both protein kinase A and Ca^(2+)/calmodulin-dependent protein kinase Ⅱ play important roles in functional responses mediated byβ1-adrenoceptors;therefore,alterations in the expression or function of these kinases can be deleterious.This review also outlines recent information on the role of protein kinase A and Ca^(2+)/calmodulin-dependent protein kinase Ⅱ in abnormal Ca^(2+)handling by cardiomyocytes from diet-induced models of pre-diabetic cardiomyopathy.
文摘Using nystatin-perforated whole-cell recording configuration, the modulatory effect of N-methyl-D-aspartate (NMDA) on γ-aminobutyric acid (GABA)-activated whole-cell currents was investigated in neurons freshly dissociated from the rat sacral dorsal commissural nucleus (SDCN). The results showed that: (i) NMDA suppressed GABA- and muscimol (Mus)-activated currents (IGABA and IMUS), respectively in the Mg2+-free external solution containing 1 μmol/L glycine at a holding potential (VH) of -40 mV in SDCN neurons. The selective NMDA receptor antagonist, D-2-amino-5-phosphonovaleric acid (APV, 100 μmol/L), inhibited the NMDA-evoked currents and blocked the NMDA-induced suppression of IGABA; (ii) when the neurons were incubated in a Ca2+-free bath or pre-loaded with a membrane-permeable Ca2+ chelator, BAPTA AM (10 nmol/L), the inhibitory effect of NMDA on IGABA disappeared. Cd2+ (10 μmol/L) or La3+(30 μmol/L), the non-selective blockers of voltage-dependent calcium channels, did not affect the suppression of IGABA by NMDA application; (iii) the suppression of IGABA by NMDA was inhibited by KN-62, a cal-cium/calmodulin-dependent protein kinase II (CaMKII) inhibitor. These results indicated that the inhibition of GABA response by NMDA is Ca2+-dependent and CaMKII is involved in the process of the Ca2+-dependent inhibition.
文摘Aim In diabetic patients, metformin appears to provide cardiovascular protection that cannot be attribu- ted only to its antihyperglycemic effects. Metformin is also known as the AMP-activated protein kinase （AMPK） ac- tivator. Our previous study suggested that metformin inhibits transforming growth factor-β1 （TGF-β1） production in a mouse heart failure model of pressure overload. TGF-β1 is a key factor in cardiac fibrosis and is usually induced by Angiotensin Ⅱ （Ang Ⅱ ） in the pressure overload mouse models. This study investigated the effect of metformin on cardiac fibrosis and TGF-β production induced by AngII and the underlying mechanisms. Methods C57/BL6 wild-type and AMPKα2 knockout mice were used. AngII （3 mg · kg-1 · d-1） was infused subcutaneously into mice for 7 days. Adult mouse cardiac fibroblasts were isolated and treated with AngII （ 1 μmol · L-1） and/or met- formin （1 mmol · L-l）. Results In C57/BL6 mice, metformin inhibits AngII-induced cardiac fibrosis. In cardi-ac fibroblasts, metformin inhibits TGF-β1 expression and production induced by AngII. AMPK inhibitor, com- pound C, reversed the effects of metformin. In vivo, AMPKα2 deficiency further increases AngII-induced TGF-β1 production. In cardiac fibroblasts, metformin inhibited AngII induced hepatocyte nuclear factor4 （HNF4ot protein level increase and HNF4α binding with TGF-β1 promoter using chromatin immunoprecipitation assay. In vivo, AMPKα2 deficiency further increased AngII-induced HNF4α protein level. Using HNF4α adenovirus, overexpress- ing HNF4α led to a 1.5-fold increase in TGF-β1 mRNA expression. HNF4a siRNA blocked AngII induced TGF- β1 production. Luciferase reporter with deleted HNF4a binding sites showed decreased TGFbl transcriptional activ- ity induced by AngII. In AMPK or2-/- heart, the inhibition of metformin on HNF4a protein was attenuated. Con- clusion Metformin inhibits AngII induced cardiac fibrosis and TGF-β1 production through AMPK activation. The underlying mechanism is that AMPK activation inhibits AngII induced HNF4α and then decreases TGF-β1 expres- sion.
文摘Inositol polyphosphate-4-phosphatase type II(INPP4B)is a newly discovered PI(3,4,5)P3 phosphatase.Many studies have revealed that INPP4B is upregulated or downregulated in tumors of the digestive system,and the abnormal expression of INPP4B may be attributed to the occurrence,development,and prognosis of tumors of the digestive system.This paper reviews studies on the correlations between INPP4B and digestive system tumors and the roles of INPP4B in the development of different tumors to provide a theoretical basis for further research on its molecular mechanism and clinical application."INPP4B"and"tumor"were searched as key words in PubMed and in the CNKI series full text database retrieval system from January 2000 to August 2023.A total of 153 Englishlanguage studies and 30 Chinese-language studies were retrieved.The following enrollment criteria were applied:(1)Studies contained information on the biological structure and functions of INPP4B;(2)studies covered the influence of abnormal expression of INPP4B in digestive system tumors;and(3)studies covered the role of INPP4B in the diagnosis,treatment,and prognosis of digestive system tumors.After excluding the literature irrelevant to this study,61 papers were finally included in the analysis.INPP4B expression is low in gastric cancer,colon cancer,pancreatic cancer,and liver cancer but it has high expression in esophageal cancer,colon cancer,pancreatic cancer,and gallbladder cancer.INPP4B is involved in the occurrence and development of digestive system tumors through the regulation of gene expression and signal transduction.The abnormal expression of INPP4B plays an important role in the development of digestive system tumors.Studies on INPP4B provide new molecular insights for the diagnosis,treatment,and prognosis evaluation of digestive system tumors.
基金Supported by Tianjin Basic Research Program (Grant No. 07JCYBJC15600)National Natural Science Foundation of China (Grant No. 30770428)+2 种基金National Key Basic Research and Development Program of China (Grant Nos. 2007CB914301, 2006CB910200)National High-Technology Research and Development Program of China (Grant No. 2006AA02A319)National Institute of Health (Grant No. MH07752)
文摘Protein kinase CK2 consists of two catalytic subunits (CK2α) and two regulatory subunits (CK2β). Here, we report the crystal structures of rat CK2α mutant (rCK2α-△C, 1—335) and CK2β (rCK2β). The overall topology of rCK2α-△C and rCK2β are very similar to the human enzyme, although large structural differences could be observed in the N-terminal domain of rCK2α-△C. Our reported structure of rCK2α-△C is in the close conformation state while the counterpart hCK2α is in the open conformation state, indi- cating the conformation of CK2α molecule has high plasticity. The structure of rCK2β represents the conformation of free CK2β. Upon CK2α binding, the C-terminal region undergoes a drastic conformational change. The major region of interaction within the interface of CK2α/CK2β may serve as a bridge to transmit the conformational change and thus regulate the activity of CK2α.
