TRPP2, a Ca^(2+)-permeable non-selective cation channel, has been shown to negatively regulate cell cycle, but the mechanism underlying this regulation is unknown. Tumor necrosis factor a(TNF-α) is a proinflammatory ...TRPP2, a Ca^(2+)-permeable non-selective cation channel, has been shown to negatively regulate cell cycle, but the mechanism underlying this regulation is unknown. Tumor necrosis factor a(TNF-α) is a proinflammatory cytokine extensively involved in immune system regulation, cell proliferation and cell survival. However, the effects and mechanisms for the role of TNF-αin laryngeal cancer remain unclear. Here, we demonstrated using western blot analyses and intracellular Ca^(2+) concentration measurements that TNF-α treatment suppressed both TRPP2 expression and ATP-induced Ca^(2+) release in a laryngeal cancer cell line(Hep-2). Knockdown of TRPP2 by a specific siRNA significantly decreased ATP-induced Ca^(2+) release and abolished the effect of TNF-α on the ATP-induced Ca^(2+) release. TNF-α treatment also enhanced Hep-2 cell proliferation and growth, as determined using cell counting and flow cytometry cell cycle assays. Moreover, TNF-α treatment down-regulated phosphorylated protein kinase R-like endoplasmic reticulum kinase(p-PERK) and phosphorylated eukaryotic translation initiation factor(p-eIF2α)expression levels, without affecting PERK and eIF2 a expression levels in Hep-2 cells. We concluded that suppressing TRPP2 expression and TRPP2-mediated Ca^(2+) signaling may be one mechanism underlying TNF-α-enhanced Hep-2 cell proliferation.These results offer new insights into the mechanisms of TNF-α-mediated laryngeal cancer cell proliferation, and provide evidences showing a potential role of TNF-α in the development of laryngeal cancer.展开更多
TRPP2 channel protein belongs to the superfamily of transient receptor potential(TRP) channels and is widely expressed in various tissues, including smooth muscle in digestive gut. Accumulating evidence has demonstrat...TRPP2 channel protein belongs to the superfamily of transient receptor potential(TRP) channels and is widely expressed in various tissues, including smooth muscle in digestive gut. Accumulating evidence has demonstrated that TRPP2 can mediate Ca^(2+) release from Ca^(2+) stores. However, the functional role of TRPP2 in gallbladder smooth muscle contraction still remains unclear. In this study, we used Ca^(2+) imaging and tension measurements to test agonist-induced intracellular Ca^(2+) concentration increase and smooth muscle contraction of guinea pig gallbladder, respectively. When TRPP2 protein was knocked down in gallbladder muscle strips from guinea pig, carbachol(CCh)-evoked Ca^(2+) release and extracellular Ca^(2+) influx were reduced significantly, and gallbladder contractions induced by endothelin 1 and cholecystokinin were suppressed markedly as well. CCh-induced gallbladder contraction was markedly suppressed by pretreatment with U73122, which inhibits phospholipase C to terminate inositol 1,4,5-trisphosphate receptor(IP3) production, and 2-aminoethoxydiphenyl borate(2APB), which inhibits IP3 recepor(IP3R) to abolish IP3R-mediated Ca^(2+) release. To confirm the role of Ca^(2+) release in CCh-induced gallbladder contraction, we used thapsigargin(TG)-to deplete Ca^(2+) stores via inhibiting sarco/endoplasmic reticulum Ca^(2+)-ATPase and eliminate the role of store-operated Ca^(2+) entry on the CCh-induced gallbladder contraction. Preincubation with 2 μmol L^(-1) TG significantly decreased the CCh-induced gallbladder contraction. In addition, pretreatments with U73122, 2APB or TG abolished the difference of the CCh-induced gallbladder contraction between TRPP2 knockdown and control groups. We conclude that TRPP2 mediates Ca^(2+) release from intracellular Ca^(2+) stores, and has an essential role in agonist-induced gallbladder muscle contraction.展开更多
利用正相和反相色谱法,从土鳖虫(Eupolyphaga seu Steleophaga)70%丙酮水提取物的乙酸乙酯萃取物中共分离纯化了17个化合物,经波谱分析分别鉴定为:1H-吡咯并[1,2-a][1,4]二氮杂卓1.5(2H)-六氢-二酮,3–对苯基酚(1),3-[(1S)-1-甲基-1-丙...利用正相和反相色谱法,从土鳖虫(Eupolyphaga seu Steleophaga)70%丙酮水提取物的乙酸乙酯萃取物中共分离纯化了17个化合物,经波谱分析分别鉴定为:1H-吡咯并[1,2-a][1,4]二氮杂卓1.5(2H)-六氢-二酮,3–对苯基酚(1),3-[(1S)-1-甲基-1-丙基]-(3S,8S)六氢-吡咯并[1,2]吡嗪-1,4-二酮(2),1,4-二氧-八氢吡咯并[1,2]-吡嗪-对乙酰氨基酚(3),1,4-二氧-八氢吡咯并[1,2]-吡嗪-丙酰胺(4),(3S,8a S)-3-丁基环己烷吡咯并[1,2-a]吡嗪-1,4-二酮(5),腺苷(6),3-核糖-2,4-二氢嘧啶二酮(7),肌酐(8),2-甲基-6-(2'3'4'-三羟基丁基)吡嗪(9),甲基尿嘧啶(胸腺嘧啶)(10),3-羟基吡啶(11),6-甲基-2,4-二氢嘧啶二酮(12),3-7-二氢嘌呤-2-酮(13),3H-咪唑并[5,9]吡啶(14),3-乙基-6,8-二羟基-7-甲基-3,4-二氢异苯并吡喃-1-酮(15),3-(4-羟基苯基)-N-甲基丙酰胺(16),6,8-二羟基-3,7-二甲基l-3,4-二氢-1H-异苯并吡喃-1-酮(17).其中化合物1为新化合物,化合物2-17为首次从该药材中分离得到.化合物1-17进行了抑制PKD1/TRPP2活性的评价,但结果显示所有化合物均没有活性.展开更多
基金supported by the Anhui Provincial Natural Science Foundation (1408085MH157)Supporting Program for Excellent Young Talents in Universities of Anhui Province, Outstanding Young Investigator of Anhui Medical University, National Natural Science Foundation of China (81570403, 81371284)Scientific Research Grant ofAnhui Medical University (2015xk1080)
文摘TRPP2, a Ca^(2+)-permeable non-selective cation channel, has been shown to negatively regulate cell cycle, but the mechanism underlying this regulation is unknown. Tumor necrosis factor a(TNF-α) is a proinflammatory cytokine extensively involved in immune system regulation, cell proliferation and cell survival. However, the effects and mechanisms for the role of TNF-αin laryngeal cancer remain unclear. Here, we demonstrated using western blot analyses and intracellular Ca^(2+) concentration measurements that TNF-α treatment suppressed both TRPP2 expression and ATP-induced Ca^(2+) release in a laryngeal cancer cell line(Hep-2). Knockdown of TRPP2 by a specific siRNA significantly decreased ATP-induced Ca^(2+) release and abolished the effect of TNF-α on the ATP-induced Ca^(2+) release. TNF-α treatment also enhanced Hep-2 cell proliferation and growth, as determined using cell counting and flow cytometry cell cycle assays. Moreover, TNF-α treatment down-regulated phosphorylated protein kinase R-like endoplasmic reticulum kinase(p-PERK) and phosphorylated eukaryotic translation initiation factor(p-eIF2α)expression levels, without affecting PERK and eIF2 a expression levels in Hep-2 cells. We concluded that suppressing TRPP2 expression and TRPP2-mediated Ca^(2+) signaling may be one mechanism underlying TNF-α-enhanced Hep-2 cell proliferation.These results offer new insights into the mechanisms of TNF-α-mediated laryngeal cancer cell proliferation, and provide evidences showing a potential role of TNF-α in the development of laryngeal cancer.
基金supported by Anhui Provincial Natural Science Foundation (1208085MH181, 1108085J11)National Natural Science Foundation of China (81371284)Young Prominent Investigator Supporting Program from Anhui Medical University and National Training Program of Innovation and Entrepreneurship for Undergraduates (201310366012)
文摘TRPP2 channel protein belongs to the superfamily of transient receptor potential(TRP) channels and is widely expressed in various tissues, including smooth muscle in digestive gut. Accumulating evidence has demonstrated that TRPP2 can mediate Ca^(2+) release from Ca^(2+) stores. However, the functional role of TRPP2 in gallbladder smooth muscle contraction still remains unclear. In this study, we used Ca^(2+) imaging and tension measurements to test agonist-induced intracellular Ca^(2+) concentration increase and smooth muscle contraction of guinea pig gallbladder, respectively. When TRPP2 protein was knocked down in gallbladder muscle strips from guinea pig, carbachol(CCh)-evoked Ca^(2+) release and extracellular Ca^(2+) influx were reduced significantly, and gallbladder contractions induced by endothelin 1 and cholecystokinin were suppressed markedly as well. CCh-induced gallbladder contraction was markedly suppressed by pretreatment with U73122, which inhibits phospholipase C to terminate inositol 1,4,5-trisphosphate receptor(IP3) production, and 2-aminoethoxydiphenyl borate(2APB), which inhibits IP3 recepor(IP3R) to abolish IP3R-mediated Ca^(2+) release. To confirm the role of Ca^(2+) release in CCh-induced gallbladder contraction, we used thapsigargin(TG)-to deplete Ca^(2+) stores via inhibiting sarco/endoplasmic reticulum Ca^(2+)-ATPase and eliminate the role of store-operated Ca^(2+) entry on the CCh-induced gallbladder contraction. Preincubation with 2 μmol L^(-1) TG significantly decreased the CCh-induced gallbladder contraction. In addition, pretreatments with U73122, 2APB or TG abolished the difference of the CCh-induced gallbladder contraction between TRPP2 knockdown and control groups. We conclude that TRPP2 mediates Ca^(2+) release from intracellular Ca^(2+) stores, and has an essential role in agonist-induced gallbladder muscle contraction.
文摘利用正相和反相色谱法,从土鳖虫(Eupolyphaga seu Steleophaga)70%丙酮水提取物的乙酸乙酯萃取物中共分离纯化了17个化合物,经波谱分析分别鉴定为:1H-吡咯并[1,2-a][1,4]二氮杂卓1.5(2H)-六氢-二酮,3–对苯基酚(1),3-[(1S)-1-甲基-1-丙基]-(3S,8S)六氢-吡咯并[1,2]吡嗪-1,4-二酮(2),1,4-二氧-八氢吡咯并[1,2]-吡嗪-对乙酰氨基酚(3),1,4-二氧-八氢吡咯并[1,2]-吡嗪-丙酰胺(4),(3S,8a S)-3-丁基环己烷吡咯并[1,2-a]吡嗪-1,4-二酮(5),腺苷(6),3-核糖-2,4-二氢嘧啶二酮(7),肌酐(8),2-甲基-6-(2'3'4'-三羟基丁基)吡嗪(9),甲基尿嘧啶(胸腺嘧啶)(10),3-羟基吡啶(11),6-甲基-2,4-二氢嘧啶二酮(12),3-7-二氢嘌呤-2-酮(13),3H-咪唑并[5,9]吡啶(14),3-乙基-6,8-二羟基-7-甲基-3,4-二氢异苯并吡喃-1-酮(15),3-(4-羟基苯基)-N-甲基丙酰胺(16),6,8-二羟基-3,7-二甲基l-3,4-二氢-1H-异苯并吡喃-1-酮(17).其中化合物1为新化合物,化合物2-17为首次从该药材中分离得到.化合物1-17进行了抑制PKD1/TRPP2活性的评价,但结果显示所有化合物均没有活性.