A new sterol, ergosta-8(9),22-diene-3,5,6,7-tetraol(3β,5α,6β,7α,22E)(A) together with three known sterols: 3β, 5α,6β-trihydroxyergosta-7,22-diene (B), 3β-hydroxy-5α,8α- epidioxyer-gosta-6,22-diene (C) and er...A new sterol, ergosta-8(9),22-diene-3,5,6,7-tetraol(3β,5α,6β,7α,22E)(A) together with three known sterols: 3β, 5α,6β-trihydroxyergosta-7,22-diene (B), 3β-hydroxy-5α,8α- epidioxyer-gosta-6,22-diene (C) and ergosterol (D) were isolated from the mycelia of an unidentified endophytic fungus separated from Castaniopsis fissa (chestnut tree). Compound A exhibited potent selective cytotoxicity against Bel-7402, NCI4460 and L-02 cell lines with IC50 values 8.445, 5.03, 13.621 μg/mL, respectively.展开更多
Aim： To investigate the activity of RRR-α-tocopheryloxybutyric acid （TOB）, an ether analog of RRR-α-tocopheryl succinate （VES）, in prostate cancer cells. Methods： VES and TOB were used to treat prostate cancer...Aim： To investigate the activity of RRR-α-tocopheryloxybutyric acid （TOB）, an ether analog of RRR-α-tocopheryl succinate （VES）, in prostate cancer cells. Methods： VES and TOB were used to treat prostate cancer LNCaP, PC3, and 22Rvl cells and primary-cultured prostate fibroblasts. The proliferation rates were determined by MTT assay, the cell viabilities were determined by trypan blue exclusion assay, and the cell deaths were evaluated by using Cell Death Detection ELISA kit. The protein expression levels were determined by Western blot analysis. Results： The MTT growth assay demonstrated that TOB could effectively suppress the proliferation of prostate cancer cells, but not normal prostate fibroblasts. Mechanism dissections revealed that TOB reduced cell viability and induced apoptosis in prostate cancer cells similar to VES. In addition, both TOB and VES suppressed prostate-specific antigen （PSA） at the transcriptional level leading to reduced PSA protein expression. Furthermore, vitamin D receptor （VDR） expression increased after the addition of TOB. Conclusion： Our data suggests that the VES derivative, TOB, is effective in inhibiting prostate cancer cell proliferation, suggesting that TOB could be used for both chemopreventive and chemotherapeutic purposes in the future.展开更多
The mechanism regulating proteasomal activity under proteotoxic stress conditions remains unclear.Here,we showed that arsenite-induced proteotoxic stress resulted in upregulation of Arabidopsis homologous PUB22 and PU...The mechanism regulating proteasomal activity under proteotoxic stress conditions remains unclear.Here,we showed that arsenite-induced proteotoxic stress resulted in upregulation of Arabidopsis homologous PUB22 and PUB23 U-boxE3 ubiquitin ligases and that pub22 pub23 double mutants displayed arsenite-insensitive seed germination and root growth phenotypes.PUB22/PUB23 downregulated 26 S proteasome activity by promoting the dissociation of the 19 S regulatory particle from the holo-proteasome complex,resulting in intracellular accumulation of UbG76 VGFP,an artificial substrate of the proteasome complex,and insoluble poly-ubiquitinated proteins.These results suggest that PUB22/PUB23 play a critical role in arsenite-induced proteotoxic stress response via negative regulation of 26 S proteasome integrity.展开更多
本文应用MDCK-p Ha MDR细胞单层模型,评价20(S)-原人参三醇(1)和20(R)-原人参三醇(2)差向异构体及达玛-20(22)E,24-二烯-3β,6α,12β-三醇(3)在血脑屏障的吸收性。为了评价三个化合物的吸收性和预测其吸收机制,对它们的双向透过性进行...本文应用MDCK-p Ha MDR细胞单层模型,评价20(S)-原人参三醇(1)和20(R)-原人参三醇(2)差向异构体及达玛-20(22)E,24-二烯-3β,6α,12β-三醇(3)在血脑屏障的吸收性。为了评价三个化合物的吸收性和预测其吸收机制,对它们的双向透过性进行了研究,并计算了相应的表观渗透系数(Papp)。在三个受试化合物中,原人参三醇差向异构体化合物1和2显示了良好的吸收性,Papp值在1×10–5 cm/s数量级;而化合物3判断为吸收不良的化合物,其Papp值小于1×10–7 cm/s。三个化合物由于结构上的差异,在细胞内产生了不同程度的蓄积。维拉帕米抑制P糖蛋白的转运实验结果表明,化合物1和2在MDCK-p Ha MDR细胞单层模型中的转运机制不仅仅是单纯的被动扩散。本文的研究结果为化合物1和2作用于脑的研究提供了实验依据。展开更多
文摘A new sterol, ergosta-8(9),22-diene-3,5,6,7-tetraol(3β,5α,6β,7α,22E)(A) together with three known sterols: 3β, 5α,6β-trihydroxyergosta-7,22-diene (B), 3β-hydroxy-5α,8α- epidioxyer-gosta-6,22-diene (C) and ergosterol (D) were isolated from the mycelia of an unidentified endophytic fungus separated from Castaniopsis fissa (chestnut tree). Compound A exhibited potent selective cytotoxicity against Bel-7402, NCI4460 and L-02 cell lines with IC50 values 8.445, 5.03, 13.621 μg/mL, respectively.
文摘Aim： To investigate the activity of RRR-α-tocopheryloxybutyric acid （TOB）, an ether analog of RRR-α-tocopheryl succinate （VES）, in prostate cancer cells. Methods： VES and TOB were used to treat prostate cancer LNCaP, PC3, and 22Rvl cells and primary-cultured prostate fibroblasts. The proliferation rates were determined by MTT assay, the cell viabilities were determined by trypan blue exclusion assay, and the cell deaths were evaluated by using Cell Death Detection ELISA kit. The protein expression levels were determined by Western blot analysis. Results： The MTT growth assay demonstrated that TOB could effectively suppress the proliferation of prostate cancer cells, but not normal prostate fibroblasts. Mechanism dissections revealed that TOB reduced cell viability and induced apoptosis in prostate cancer cells similar to VES. In addition, both TOB and VES suppressed prostate-specific antigen （PSA） at the transcriptional level leading to reduced PSA protein expression. Furthermore, vitamin D receptor （VDR） expression increased after the addition of TOB. Conclusion： Our data suggests that the VES derivative, TOB, is effective in inhibiting prostate cancer cell proliferation, suggesting that TOB could be used for both chemopreventive and chemotherapeutic purposes in the future.
基金supported by grants from the National Research Foundation(Mid-Career Researcher Program Project No.2017R1A2B2006750 and Basic Science Research Program Project No.2018R1A6A1A03025607),Republic of Korea,to Woo T.Kim。
文摘The mechanism regulating proteasomal activity under proteotoxic stress conditions remains unclear.Here,we showed that arsenite-induced proteotoxic stress resulted in upregulation of Arabidopsis homologous PUB22 and PUB23 U-boxE3 ubiquitin ligases and that pub22 pub23 double mutants displayed arsenite-insensitive seed germination and root growth phenotypes.PUB22/PUB23 downregulated 26 S proteasome activity by promoting the dissociation of the 19 S regulatory particle from the holo-proteasome complex,resulting in intracellular accumulation of UbG76 VGFP,an artificial substrate of the proteasome complex,and insoluble poly-ubiquitinated proteins.These results suggest that PUB22/PUB23 play a critical role in arsenite-induced proteotoxic stress response via negative regulation of 26 S proteasome integrity.
基金The National New Drug R&D Program(Grant No.2011BAI07B082009ZX09301-010)of China
文摘本文应用MDCK-p Ha MDR细胞单层模型,评价20(S)-原人参三醇(1)和20(R)-原人参三醇(2)差向异构体及达玛-20(22)E,24-二烯-3β,6α,12β-三醇(3)在血脑屏障的吸收性。为了评价三个化合物的吸收性和预测其吸收机制,对它们的双向透过性进行了研究,并计算了相应的表观渗透系数(Papp)。在三个受试化合物中,原人参三醇差向异构体化合物1和2显示了良好的吸收性,Papp值在1×10–5 cm/s数量级;而化合物3判断为吸收不良的化合物,其Papp值小于1×10–7 cm/s。三个化合物由于结构上的差异,在细胞内产生了不同程度的蓄积。维拉帕米抑制P糖蛋白的转运实验结果表明,化合物1和2在MDCK-p Ha MDR细胞单层模型中的转运机制不仅仅是单纯的被动扩散。本文的研究结果为化合物1和2作用于脑的研究提供了实验依据。
