Objective:Vascular remodeling due to chronic hypoxia(CH)occurs not only in the pulmonary arteries but also in the pulmonary veins.Pulmonary vascular remodeling arises from the proliferation of pulmonary vascular myocy...Objective:Vascular remodeling due to chronic hypoxia(CH)occurs not only in the pulmonary arteries but also in the pulmonary veins.Pulmonary vascular remodeling arises from the proliferation of pulmonary vascular myocytes.However,the mechanism by which CH induces the proliferation of pulmonary vein smooth muscle cells(PVSMCs)is unknown.This study aimed to investigate the mechanism by which CH affects the proliferation of PVSMCs.Methods:PVSMCs were isolated from rat distal pulmonary veins and exposed to CH(4%O2,60h),and the expression of the calcium-sensitive receptor(CaSR)was detected by Western blotting and immunofluorescence.MTT assay was used to detect the proliferation viability of the cells,and the changes in the intracellular calcium concentration were detected by laser confocal scanning technique.Results:CaSR expression was present in rat distal PVSMCs,and CaSR protein expression was upregulated under hypoxia.The positive regulator spermine not only enhanced CH-induced CaSR upregulation but also enhanced CH-induced increase in cell viability and calcium ion concentration.The negative CaSR regulator NPS2143 not only attenuated CH-induced CaSR upregulation but also inhibited CH-induced cell viability and calcium ion concentration.Conclusion:CaSR-mediated hyperproliferation is a novel pathogenic mechanism for the development of proliferation in distal PVSMCs under CH conditions.展开更多
AIM： To test the hypothesis that calcium sensing receptor （CASR） polymorphisms are associated with chronic pancreatitis （CP）, and to determine whether serine protease inhibitor Kazal 1type （SPINK1） N34S or alco...AIM： To test the hypothesis that calcium sensing receptor （CASR） polymorphisms are associated with chronic pancreatitis （CP）, and to determine whether serine protease inhibitor Kazal 1type （SPINK1） N34S or alcohol are necessary co-factors in its etiology. METHODS： Initially, 115 subjects with pancreatitis and 66 controls were evaluated, of whom 57 patients and 21 controls were predetermined to carry the high-risk SPINK1 N34S polymorphism. We sequenced CASR gene exons 2, 3, 4, 5 and 7, areas containing the majority of reported polymorphisms and novel mutations. Based on the initial results, we added 223 patients and 239 controls to analyze three common nonsynonymous single nucleotide polymorphisms （SNPs） in exon 7 （A986S, R990G, and Q1011E）. RESULTS： The CASR exon 7 R990G polyrnorphism was significantly associated with CP （OR, 2.01; 95% CI, 1.12-3.59; P = 0.015）. The association between CASR R990G and CP was stronger in subjects who reported moderate or heavy alcohol consumption （OR, 3.12; 95% CI, 1.14-9.13; P = 0.018）. There was no association between the various CASR genotypes and SPINK1 N34S in pancreatitis. None of the novel CASR polymorphisms reported from Germany and India was detected. CONCLUSION： Our United States-based study confirmed an association of CASR and CP and for the first time demonstrated that CASR R990G is a significant risk factor for CP. We also conclude that the risk of CP with CASR R990G is increased in subjects with moderate to heavy alcohol consumption.展开更多
Objective： Calcium-sensing receptors （CaSRs） are G-protein coupled receptors which maintain systemic calcium homeostasis and participate in hormone secretion, activation of ion channels, cell apoptosis, proliferati...Objective： Calcium-sensing receptors （CaSRs） are G-protein coupled receptors which maintain systemic calcium homeostasis and participate in hormone secretion, activation of ion channels, cell apoptosis, proliferation, and differentiation. Previous studies have shown that CaSRs induce apoptosis in isolated adult rat heart and in normal neonatal rat cardiomyocytes by G-protein-PLC-IP3 signaling transduction. However, little knowledge is presently available concerning the role of CaSRs in the apoptosis induced by ischemia and reperfusion in neonatal cardiomyocytes. Methods： Primary neonatal rat ventricular cardiomyocytes were incubated in ischemiamimetic solution for 2 h, and then re-incubated in normal culture medium for 24 h to establish a model of simu- lated ischemia/reperfusion （I/R）. Cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase- mediated dUTP nick end labeling （TUNEL）. The expression of CaSRs mRNA was detected by real-time reverse transcription polymerase chain reaction （RT-PCR）. In addition, the expressions of caspase-3 and Bcl-2 were analyzed by western blot. Results： The simulated I/R enhanced the expression of CaSRs and cardiomyocyte apoptosis. GdCl3, a specific activator of CaSRs, further increased the expression of CaSRs and cardiomyocyte apoptosis, along with up-regulation of caspase-3 and down-regulation of Bcl-2. Conclusion： CaSRs are associated with UR injury and apoptosis in neonatal rat ventricular cardiomyocytes via suppressing Bcl-2 and promoting caspase-3 expression.展开更多
Astrocytes＇ roles in late-onset Alzheimer＇s disease （LOAD） promotion are important, since they survive soluble or fibrillar amyloid-β peptides （Aβs） neurotoxic effects, undergo alterations of intracellular and...Astrocytes＇ roles in late-onset Alzheimer＇s disease （LOAD） promotion are important, since they survive soluble or fibrillar amyloid-β peptides （Aβs） neurotoxic effects, undergo alterations of intracellular and intercellular Ca2＋ signaling and gliotransmitters release via the Aβ/a7-nAChR （αT-nicotinic acetylcholine receptor） signaling, and overproduce/oversecrete newly synthesized Aβ42 oligomers, NO, and VEGF-A via the Aβ/CaSR （calcium-sensing receptor） signaling. Recently, it was suggested that the NMDAR （N-methyl-D-aspartate receptor） inhibitor nitromemantine would block the synapse-destroying effects of Aβ/α7-nAChR signaling. Yet, this and the progressive extracellular accrual and spreading of Aβ42 oligomers would be stopped well upstream by NPS 2143, an allosteric CaSR antagonist （calcilytic）.展开更多
Background:The mechanism concerning gingival overgrowth as a side effect of phenytoin, a therapeutic drug for epilepsy has been still unclear. As one of mechanisms, by measuring the intracellular calcium concentration...Background:The mechanism concerning gingival overgrowth as a side effect of phenytoin, a therapeutic drug for epilepsy has been still unclear. As one of mechanisms, by measuring the intracellular calcium concentration ([Ca2+]i) of the gingival fibroblasts, it has been advocated that there is relationship between gingival overgrowth and phenytoin-induced alterations in the [Ca2+]i in gingival fibroblasts. To confirm that phenytoin elevates the [Ca2+]i, and if so, to find out its mode of action. Methods: The [Ca2+]i was measured with the Ca2+-sensitive fluorescent dye fura-2/AM. Cells were soaked in a flexiperm chamber and perfused by a saline. Drugs at appropriate concentrations were added to the perfusate. Results: Phenytoin concentration-dependently elevated the [Ca2+]i. NPS2390, a calcium-sensing receptor (CaSR) blocker, significantly suppressed the phenytoin-induced [Ca2+]i elevation. U73122, a phospholipase C (PLC) inhibitor, inihibited the phenytoin-induced [Ca2+]i elevation. TMB-8, a blocker of inositol triphophate (IP3) receptors in ER, significantly depressed the phenytoin-induced [Ca2+]i elevation. m-3M3FBS, a PLC activator, enhanced the phenytoin-induced [Ca2+]i elevation. From the findings obtained, it is discussed as follows: The Ca2+-free saline and NPS2390, a CaSR antagonist, inhibited the phenytoin-induced [Ca2+]i rise;These results indicate that CaSRs exist in gingival fibroblasts and that CaSRs are involved in the phenytoin-induced [Ca2+]i rise;U73122 and TMB-8 depressed the phenytoin-induced [Ca2+]i elevation and furthermore, m-3M3FBS enhanced the phenytoin-induced [Ca2+]i elevation, showing that the Ca2+ release from the ER is involved in the phenytoin-induced [Ca2+]i elevation. Conclusion: We have concluded that phenytoin elevates the [Ca2+]i by activating CaSRs and enhancing the Ca2+ release from the Ca2+ stores in gingival fibroblasts.展开更多
目的:观察花旗泽仁对胰岛素抵抗(IR)大鼠肝脏组织中钙敏感受体(Ca SR)mRNA、蛋白表达及蛋白激酶B(AKT)活性的影响,探讨花旗泽仁改善2型糖尿病胰岛素抵抗的作用机制。方法:雄性Wistar大鼠用复合脂肪乳连续灌胃4周配合小剂量注射链脲佐菌...目的:观察花旗泽仁对胰岛素抵抗(IR)大鼠肝脏组织中钙敏感受体(Ca SR)mRNA、蛋白表达及蛋白激酶B(AKT)活性的影响,探讨花旗泽仁改善2型糖尿病胰岛素抵抗的作用机制。方法:雄性Wistar大鼠用复合脂肪乳连续灌胃4周配合小剂量注射链脲佐菌素的方法复制2型糖尿病胰岛素抵抗模型,将大鼠随机分为花旗泽仁组、阳性对照组、模型对照组、空白对照组。检测空腹血糖(FBG)及空腹血清胰岛素(FINS),并计算胰岛素敏感指数(ISI);采用qRT-PCR、Western blot技术检测Ca SR mRNA、Ca SR蛋白、磷酸化AKT(Ser473和Thr308)蛋白表达水平。结果:与空白对照组比较,模型对照组组大鼠FBG及FINS水平明显增高,ISI显著降低;与模型对照组相比,花旗泽仁组和阳性对照组大鼠FBG和FINS水平明显降低,ISI明显升高;与空白对照组比较,模型对照组大鼠肝脏组织中Ca SR mRNA表达水平明显降低;与模型对照组相比,花旗泽仁组和阳性对照组大鼠肝脏组织中Ca SR mRNA表达水平显著增高;与空白对照组比较,模型组大鼠肝脏组织中Ca SR蛋白、磷酸化AKT(Ser473和Thr308)蛋白表达量均显著降低;与模型对照组相比,花旗泽仁组和阳性对照组大鼠肝脏组织中Ca SR蛋白、磷酸化AKT(Ser473和Thr308)蛋白表达量均明显增加。结论:花旗泽仁可能通过调节Ca SR基因及蛋白表达,改善2型糖尿病胰岛素抵抗。展开更多
In order to clarify the potential role of calcium sensing receptor（Ca SR）, a typical G protein coupled receptor（GPCR）, in hyperglacemia-induced macroangiopathy, experimental hyperglycemia models in vivo and in vit...In order to clarify the potential role of calcium sensing receptor（Ca SR）, a typical G protein coupled receptor（GPCR）, in hyperglacemia-induced macroangiopathy, experimental hyperglycemia models in vivo and in vitro were prepared. Firstly, SD rats were divided into control group（n=10） and diabetes group（n=10）, and diabetic model was induced via high-fat diet feeding and streptozotocin（STZ, 30 mg/kg） injection. Hydroxyproline level, determined via Choramnie T oxidation method, in vessel wall in diabetic rats was 30% more than that in control group. The gene transcription and expression levels were detected by real-time PCR and Western blotting, respectively. Both of collagen Ⅰ and Ⅲ mR NA levels in diabetic aorta were nearly twice those in normal aorta. The cleaved caspase-3 and-9 were elevated 1.5 and 2.5 times respectively in diabetic vascular cells. As compared with controls, m RNA and protein levels of CaS R in aorta were increased by 3 and 1.5 times in diabetes group. The expression levels of Bax as well as pro-apoptotic kinases（phospho-p38 and phosphor-JNK） were also increased 2, 0.5 and 0.5 times respectively in diabetic rats. To further validate the involvement of Ca SR in cell apoptosis and explore the potential mechanism, the endothelial cell line（human umbilical vascular endothelial cells, HUVECs） was stimulated with high concentration of glucose（33 mmol/L） to mimic hyperglycemia in vitro. Cell-based assays also showed that the Ca SR level and key apoptotic proteins（cleaved caspase-3 and-9, Bax, phospho-p38 and phosphor-JNK） were elevated in response to stimulation, and inhibition of Ca SR by using specific inhibitor（NPS-2143, 10 μmol/L） could protect cells against apoptosis. Our results demonstrated that Ca SR might take important part in the development of diabetic macroangiopathy through promoting cell apoptosis induced by hyperglycemia.展开更多
基金Guangzhou Municipal Health Science and Technology Project(Project No.20211A010087)Guangzhou Panyu District Science and Technology Program Project(Project No.2020-Z04-012)。
文摘Objective:Vascular remodeling due to chronic hypoxia(CH)occurs not only in the pulmonary arteries but also in the pulmonary veins.Pulmonary vascular remodeling arises from the proliferation of pulmonary vascular myocytes.However,the mechanism by which CH induces the proliferation of pulmonary vein smooth muscle cells(PVSMCs)is unknown.This study aimed to investigate the mechanism by which CH affects the proliferation of PVSMCs.Methods:PVSMCs were isolated from rat distal pulmonary veins and exposed to CH(4%O2,60h),and the expression of the calcium-sensitive receptor(CaSR)was detected by Western blotting and immunofluorescence.MTT assay was used to detect the proliferation viability of the cells,and the changes in the intracellular calcium concentration were detected by laser confocal scanning technique.Results:CaSR expression was present in rat distal PVSMCs,and CaSR protein expression was upregulated under hypoxia.The positive regulator spermine not only enhanced CH-induced CaSR upregulation but also enhanced CH-induced increase in cell viability and calcium ion concentration.The negative CaSR regulator NPS2143 not only attenuated CH-induced CaSR upregulation but also inhibited CH-induced cell viability and calcium ion concentration.Conclusion:CaSR-mediated hyperproliferation is a novel pathogenic mechanism for the development of proliferation in distal PVSMCs under CH conditions.
基金NIH R01 DK061451 (DCW) and Andrew and Michelle Aloe
文摘AIM： To test the hypothesis that calcium sensing receptor （CASR） polymorphisms are associated with chronic pancreatitis （CP）, and to determine whether serine protease inhibitor Kazal 1type （SPINK1） N34S or alcohol are necessary co-factors in its etiology. METHODS： Initially, 115 subjects with pancreatitis and 66 controls were evaluated, of whom 57 patients and 21 controls were predetermined to carry the high-risk SPINK1 N34S polymorphism. We sequenced CASR gene exons 2, 3, 4, 5 and 7, areas containing the majority of reported polymorphisms and novel mutations. Based on the initial results, we added 223 patients and 239 controls to analyze three common nonsynonymous single nucleotide polymorphisms （SNPs） in exon 7 （A986S, R990G, and Q1011E）. RESULTS： The CASR exon 7 R990G polyrnorphism was significantly associated with CP （OR, 2.01; 95% CI, 1.12-3.59; P = 0.015）. The association between CASR R990G and CP was stronger in subjects who reported moderate or heavy alcohol consumption （OR, 3.12; 95% CI, 1.14-9.13; P = 0.018）. There was no association between the various CASR genotypes and SPINK1 N34S in pancreatitis. None of the novel CASR polymorphisms reported from Germany and India was detected. CONCLUSION： Our United States-based study confirmed an association of CASR and CP and for the first time demonstrated that CASR R990G is a significant risk factor for CP. We also conclude that the risk of CP with CASR R990G is increased in subjects with moderate to heavy alcohol consumption.
基金supported by a grant from the Nature Science Foundation of the Education Department of Jiangsu Province(No.06kjb320006)
文摘Objective： Calcium-sensing receptors （CaSRs） are G-protein coupled receptors which maintain systemic calcium homeostasis and participate in hormone secretion, activation of ion channels, cell apoptosis, proliferation, and differentiation. Previous studies have shown that CaSRs induce apoptosis in isolated adult rat heart and in normal neonatal rat cardiomyocytes by G-protein-PLC-IP3 signaling transduction. However, little knowledge is presently available concerning the role of CaSRs in the apoptosis induced by ischemia and reperfusion in neonatal cardiomyocytes. Methods： Primary neonatal rat ventricular cardiomyocytes were incubated in ischemiamimetic solution for 2 h, and then re-incubated in normal culture medium for 24 h to establish a model of simu- lated ischemia/reperfusion （I/R）. Cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase- mediated dUTP nick end labeling （TUNEL）. The expression of CaSRs mRNA was detected by real-time reverse transcription polymerase chain reaction （RT-PCR）. In addition, the expressions of caspase-3 and Bcl-2 were analyzed by western blot. Results： The simulated I/R enhanced the expression of CaSRs and cardiomyocyte apoptosis. GdCl3, a specific activator of CaSRs, further increased the expression of CaSRs and cardiomyocyte apoptosis, along with up-regulation of caspase-3 and down-regulation of Bcl-2. Conclusion： CaSRs are associated with UR injury and apoptosis in neonatal rat ventricular cardiomyocytes via suppressing Bcl-2 and promoting caspase-3 expression.
文摘Astrocytes＇ roles in late-onset Alzheimer＇s disease （LOAD） promotion are important, since they survive soluble or fibrillar amyloid-β peptides （Aβs） neurotoxic effects, undergo alterations of intracellular and intercellular Ca2＋ signaling and gliotransmitters release via the Aβ/a7-nAChR （αT-nicotinic acetylcholine receptor） signaling, and overproduce/oversecrete newly synthesized Aβ42 oligomers, NO, and VEGF-A via the Aβ/CaSR （calcium-sensing receptor） signaling. Recently, it was suggested that the NMDAR （N-methyl-D-aspartate receptor） inhibitor nitromemantine would block the synapse-destroying effects of Aβ/α7-nAChR signaling. Yet, this and the progressive extracellular accrual and spreading of Aβ42 oligomers would be stopped well upstream by NPS 2143, an allosteric CaSR antagonist （calcilytic）.
文摘Background:The mechanism concerning gingival overgrowth as a side effect of phenytoin, a therapeutic drug for epilepsy has been still unclear. As one of mechanisms, by measuring the intracellular calcium concentration ([Ca2+]i) of the gingival fibroblasts, it has been advocated that there is relationship between gingival overgrowth and phenytoin-induced alterations in the [Ca2+]i in gingival fibroblasts. To confirm that phenytoin elevates the [Ca2+]i, and if so, to find out its mode of action. Methods: The [Ca2+]i was measured with the Ca2+-sensitive fluorescent dye fura-2/AM. Cells were soaked in a flexiperm chamber and perfused by a saline. Drugs at appropriate concentrations were added to the perfusate. Results: Phenytoin concentration-dependently elevated the [Ca2+]i. NPS2390, a calcium-sensing receptor (CaSR) blocker, significantly suppressed the phenytoin-induced [Ca2+]i elevation. U73122, a phospholipase C (PLC) inhibitor, inihibited the phenytoin-induced [Ca2+]i elevation. TMB-8, a blocker of inositol triphophate (IP3) receptors in ER, significantly depressed the phenytoin-induced [Ca2+]i elevation. m-3M3FBS, a PLC activator, enhanced the phenytoin-induced [Ca2+]i elevation. From the findings obtained, it is discussed as follows: The Ca2+-free saline and NPS2390, a CaSR antagonist, inhibited the phenytoin-induced [Ca2+]i rise;These results indicate that CaSRs exist in gingival fibroblasts and that CaSRs are involved in the phenytoin-induced [Ca2+]i rise;U73122 and TMB-8 depressed the phenytoin-induced [Ca2+]i elevation and furthermore, m-3M3FBS enhanced the phenytoin-induced [Ca2+]i elevation, showing that the Ca2+ release from the ER is involved in the phenytoin-induced [Ca2+]i elevation. Conclusion: We have concluded that phenytoin elevates the [Ca2+]i by activating CaSRs and enhancing the Ca2+ release from the Ca2+ stores in gingival fibroblasts.
文摘目的:观察花旗泽仁对胰岛素抵抗(IR)大鼠肝脏组织中钙敏感受体(Ca SR)mRNA、蛋白表达及蛋白激酶B(AKT)活性的影响,探讨花旗泽仁改善2型糖尿病胰岛素抵抗的作用机制。方法:雄性Wistar大鼠用复合脂肪乳连续灌胃4周配合小剂量注射链脲佐菌素的方法复制2型糖尿病胰岛素抵抗模型,将大鼠随机分为花旗泽仁组、阳性对照组、模型对照组、空白对照组。检测空腹血糖(FBG)及空腹血清胰岛素(FINS),并计算胰岛素敏感指数(ISI);采用qRT-PCR、Western blot技术检测Ca SR mRNA、Ca SR蛋白、磷酸化AKT(Ser473和Thr308)蛋白表达水平。结果:与空白对照组比较,模型对照组组大鼠FBG及FINS水平明显增高,ISI显著降低;与模型对照组相比,花旗泽仁组和阳性对照组大鼠FBG和FINS水平明显降低,ISI明显升高;与空白对照组比较,模型对照组大鼠肝脏组织中Ca SR mRNA表达水平明显降低;与模型对照组相比,花旗泽仁组和阳性对照组大鼠肝脏组织中Ca SR mRNA表达水平显著增高;与空白对照组比较,模型组大鼠肝脏组织中Ca SR蛋白、磷酸化AKT(Ser473和Thr308)蛋白表达量均显著降低;与模型对照组相比,花旗泽仁组和阳性对照组大鼠肝脏组织中Ca SR蛋白、磷酸化AKT(Ser473和Thr308)蛋白表达量均明显增加。结论:花旗泽仁可能通过调节Ca SR基因及蛋白表达,改善2型糖尿病胰岛素抵抗。
基金supported by General Project of Health Department of Hubei Province,China(No.2013-JX6B75)
文摘In order to clarify the potential role of calcium sensing receptor（Ca SR）, a typical G protein coupled receptor（GPCR）, in hyperglacemia-induced macroangiopathy, experimental hyperglycemia models in vivo and in vitro were prepared. Firstly, SD rats were divided into control group（n=10） and diabetes group（n=10）, and diabetic model was induced via high-fat diet feeding and streptozotocin（STZ, 30 mg/kg） injection. Hydroxyproline level, determined via Choramnie T oxidation method, in vessel wall in diabetic rats was 30% more than that in control group. The gene transcription and expression levels were detected by real-time PCR and Western blotting, respectively. Both of collagen Ⅰ and Ⅲ mR NA levels in diabetic aorta were nearly twice those in normal aorta. The cleaved caspase-3 and-9 were elevated 1.5 and 2.5 times respectively in diabetic vascular cells. As compared with controls, m RNA and protein levels of CaS R in aorta were increased by 3 and 1.5 times in diabetes group. The expression levels of Bax as well as pro-apoptotic kinases（phospho-p38 and phosphor-JNK） were also increased 2, 0.5 and 0.5 times respectively in diabetic rats. To further validate the involvement of Ca SR in cell apoptosis and explore the potential mechanism, the endothelial cell line（human umbilical vascular endothelial cells, HUVECs） was stimulated with high concentration of glucose（33 mmol/L） to mimic hyperglycemia in vitro. Cell-based assays also showed that the Ca SR level and key apoptotic proteins（cleaved caspase-3 and-9, Bax, phospho-p38 and phosphor-JNK） were elevated in response to stimulation, and inhibition of Ca SR by using specific inhibitor（NPS-2143, 10 μmol/L） could protect cells against apoptosis. Our results demonstrated that Ca SR might take important part in the development of diabetic macroangiopathy through promoting cell apoptosis induced by hyperglycemia.
