AIM To establish a functional and molecular model of the intracellular pH(pH_i) regulatory mechanism in human induced pluripotent stem cells(hiPSCs).METHODS hiP SCs(HPS0077) were kindly provided by Dr. Dai from the Tr...AIM To establish a functional and molecular model of the intracellular pH(pH_i) regulatory mechanism in human induced pluripotent stem cells(hiPSCs).METHODS hiP SCs(HPS0077) were kindly provided by Dr. Dai from the Tri-Service General Hospital(IRB No. B-106-09). Changes in the pH_i were detected either by microspectrofluorimetry or by a multimode reader with a pH-sensitive fluorescent probe, BCECF, and the fluorescent ratio was calibrated by the high K^+/nigericin method. NH_4Cl and Na-acetate prepulse techniques were used to induce rapid intracellular acidosis and alkalization, respectively. The buffering power(β) was calculated from the ΔpH_i induced by perfusing different concentrations of(NH_4)_2SO_4. Western blot techniques and immunocytochemistry staining were used to detect the protein expression of pH_i regulators and pluripotency markers.RESULTS In this study, our results indicated that(1) the steadystate pH_i value was found to be 7.5 ± 0.01(n = 20) and 7.68 ± 0.01(n =20) in HEPES and 5% CO_2/HCO_3^- buffered systems, respectively, which were much greater than that in normal adult cells(7.2);(2) in a CO_2/HCO_3^--buffered system, the values of total intracellular buffering power(β) can be described by the following equation: β_(tot) = 107.79(pH_i)~2-1522.2(pH_i) + 5396.9(correlation coefficient R^2 = 0.85), in the estimated pH_i range of 7.1- 8.0;(3) the Na^+/H^+ exchanger(NHE) and the Na^+/HCO_3^- cotransporter(NBC) were found to be functionally activated for acid extrusion for pHi values less than 7.5 and 7.68, respectively;(4) V-ATPase and some other unknown Na^+-independent acid extruder(s) could only be functionally detected for pHi values less than 7.1;(5) the Cl^-/OH^- exchanger(CHE) and the Cl^- /HCO_3 anion exchanger(AE) were found to be responsible for the weakening of intracellular proton loading;(6) besides the CHE and the AE, a Cl^--independent acid loading mechanism was functionally identified; and(7) in hiPSCs, a strong positive correlation was observed between the loss of pluripote展开更多
目的:研究NHE-1与肝星状细胞增殖的关系及姜黄素对其的影响,初步探讨肝纤维化的形成机制.方法:选择肝星状细胞系作为体外研究对象,用不同浓度(1、10、20μmol/L)的姜黄素处理大鼠肝星状细胞;以MTT比色法测定肝星状细胞的增殖;酶联免疫...目的:研究NHE-1与肝星状细胞增殖的关系及姜黄素对其的影响,初步探讨肝纤维化的形成机制.方法:选择肝星状细胞系作为体外研究对象,用不同浓度(1、10、20μmol/L)的姜黄素处理大鼠肝星状细胞;以MTT比色法测定肝星状细胞的增殖;酶联免疫吸附法(ELISA)测定Ⅰ型胶原含量,RT-PCR法检测肝星状细胞Na+/H-泵(NHE-1mRNA)的表达.结果:各浓度姜黄素可明显下调肝星状细胞NHE-1mRNA表达(0.6401±0.0063,0.2391±0.0039,0.1437±0.0044vs0.7214±0.0155,P<0.05),降低培养上清液中Ⅰ型胶原的水平(199.40±16.22,182.37±14.72,169.91±15.80ng/mgpro vs 216.35±17.19ng/mgpro,P<0.05),抑制肝星状细胞的增殖,并呈剂量依赖性.结论:姜黄素可能通过调控肝星状细胞NHE-1mRNA的表达来抑制HSC的增殖及Ⅰ型胶原的合成等机制,从而抑制肝纤维化的形成.展开更多
A series of novel derivatives of ligustrazine linked with substituted benzoyl guanidine were synthesized. These compounds have not been reported in literature, and their chemical structures were confirmed by IR, ^1H N...A series of novel derivatives of ligustrazine linked with substituted benzoyl guanidine were synthesized. These compounds have not been reported in literature, and their chemical structures were confirmed by IR, ^1H NMR and MS. The results of NHE1 inhibitory activity test showed that compounds I2, I3, I4, I6, and I7 possess more potent NHE1 inhibitory activity than cariporide.展开更多
基金Supported by Ministry of Science and Technology Grants of Taiwan,No.MOST 106-2320-B-016-003-MY2(to Loh SH)and No.MOST 106-2314-B-016-037-MY3(to Tsai YT)National Defense Medical Center Grants of Taiwan,No.MAB-106-033(to Loh SH),No.MAB-105-043 and No.MAB-106-034(to Dai NZ)Teh-Tzer Study Group for Human Medical Research Foundation of Taiwan,No.A1061037 and No.A1061054(to Loh SH)
文摘AIM To establish a functional and molecular model of the intracellular pH(pH_i) regulatory mechanism in human induced pluripotent stem cells(hiPSCs).METHODS hiP SCs(HPS0077) were kindly provided by Dr. Dai from the Tri-Service General Hospital(IRB No. B-106-09). Changes in the pH_i were detected either by microspectrofluorimetry or by a multimode reader with a pH-sensitive fluorescent probe, BCECF, and the fluorescent ratio was calibrated by the high K^+/nigericin method. NH_4Cl and Na-acetate prepulse techniques were used to induce rapid intracellular acidosis and alkalization, respectively. The buffering power(β) was calculated from the ΔpH_i induced by perfusing different concentrations of(NH_4)_2SO_4. Western blot techniques and immunocytochemistry staining were used to detect the protein expression of pH_i regulators and pluripotency markers.RESULTS In this study, our results indicated that(1) the steadystate pH_i value was found to be 7.5 ± 0.01(n = 20) and 7.68 ± 0.01(n =20) in HEPES and 5% CO_2/HCO_3^- buffered systems, respectively, which were much greater than that in normal adult cells(7.2);(2) in a CO_2/HCO_3^--buffered system, the values of total intracellular buffering power(β) can be described by the following equation: β_(tot) = 107.79(pH_i)~2-1522.2(pH_i) + 5396.9(correlation coefficient R^2 = 0.85), in the estimated pH_i range of 7.1- 8.0;(3) the Na^+/H^+ exchanger(NHE) and the Na^+/HCO_3^- cotransporter(NBC) were found to be functionally activated for acid extrusion for pHi values less than 7.5 and 7.68, respectively;(4) V-ATPase and some other unknown Na^+-independent acid extruder(s) could only be functionally detected for pHi values less than 7.1;(5) the Cl^-/OH^- exchanger(CHE) and the Cl^- /HCO_3 anion exchanger(AE) were found to be responsible for the weakening of intracellular proton loading;(6) besides the CHE and the AE, a Cl^--independent acid loading mechanism was functionally identified; and(7) in hiPSCs, a strong positive correlation was observed between the loss of pluripote
文摘目的:研究NHE-1与肝星状细胞增殖的关系及姜黄素对其的影响,初步探讨肝纤维化的形成机制.方法:选择肝星状细胞系作为体外研究对象,用不同浓度(1、10、20μmol/L)的姜黄素处理大鼠肝星状细胞;以MTT比色法测定肝星状细胞的增殖;酶联免疫吸附法(ELISA)测定Ⅰ型胶原含量,RT-PCR法检测肝星状细胞Na+/H-泵(NHE-1mRNA)的表达.结果:各浓度姜黄素可明显下调肝星状细胞NHE-1mRNA表达(0.6401±0.0063,0.2391±0.0039,0.1437±0.0044vs0.7214±0.0155,P<0.05),降低培养上清液中Ⅰ型胶原的水平(199.40±16.22,182.37±14.72,169.91±15.80ng/mgpro vs 216.35±17.19ng/mgpro,P<0.05),抑制肝星状细胞的增殖,并呈剂量依赖性.结论:姜黄素可能通过调控肝星状细胞NHE-1mRNA的表达来抑制HSC的增殖及Ⅰ型胶原的合成等机制,从而抑制肝纤维化的形成.
文摘A series of novel derivatives of ligustrazine linked with substituted benzoyl guanidine were synthesized. These compounds have not been reported in literature, and their chemical structures were confirmed by IR, ^1H NMR and MS. The results of NHE1 inhibitory activity test showed that compounds I2, I3, I4, I6, and I7 possess more potent NHE1 inhibitory activity than cariporide.
