Photodynamic therapy(PDT)usually shows limited efficacy in solid tumors since traditional PDT is O_(2)^(-)dependent while solid tumors are inherently hypoxic.In addition,hypoxic tumor cells possess antiapoptotic pathw...Photodynamic therapy(PDT)usually shows limited efficacy in solid tumors since traditional PDT is O_(2)^(-)dependent while solid tumors are inherently hypoxic.In addition,hypoxic tumor cells possess antiapoptotic pathways that resist PDT-induced apoptosis.Therefore,developing photosensitizers(PSs)that show low O_(2)^(-)dependency and can induce nonapoptotic cell death pathways is critically needed.Herein,a series of Ru(II)polypyridine complex-based PSs,RuNMe,RuH,and RuCN,were synthesized,and their applications against hypoxic tumor cells through PDT were investigated.All three complexes showthe ability to generate the superoxide anion radical(·O_(2)^(-)),which is the type I photoreaction and less O_(2)^(-)dependent.RuNMe shows the best PDT performance against MCF-7 cells and three-dimensional multicellular spheroids,due to its higher cellular uptake and more reactive oxygen species generation.More importantly,RuNMe-incubated MCF-7 cells show photoinduced ferroptosis as evidenced by glutathione peroxidase 4 downregulation and lipid peroxide accumulation.This work not only develops a novel ferroptosis-inducing Ru(II)complex with the type I PDT process but also offers an effective strategy to solve tumor hypoxia in PDT.展开更多
The polarographic catalytic wave of oxygen reduction caused by mefenamic acid (MA) with redox properties was reported in this paper. The electrochemical process of the catalytic wave was proposed that the superoxide a...The polarographic catalytic wave of oxygen reduction caused by mefenamic acid (MA) with redox properties was reported in this paper. The electrochemical process of the catalytic wave was proposed that the superoxide anion O(?) was generated polarographically and the dismutation of the O(?) was catalyzed by MA to reproduce O_2 and H_2O_2. This explained chemically the scavenging of the O_2^- by MA im biomedical area. Based on the catalytic wave, a new method for the determination of MA by single-sweep polarography was developed.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(grant nos.22122701,21731004,91953201,92153303,21977044,and 21907050)the Natural Science Foundation of Jiangsu Province(grant nos.BK20202004 and BK20190282)the Excellent Research Program of Nanjing University(grant no.ZYJH004).
文摘Photodynamic therapy(PDT)usually shows limited efficacy in solid tumors since traditional PDT is O_(2)^(-)dependent while solid tumors are inherently hypoxic.In addition,hypoxic tumor cells possess antiapoptotic pathways that resist PDT-induced apoptosis.Therefore,developing photosensitizers(PSs)that show low O_(2)^(-)dependency and can induce nonapoptotic cell death pathways is critically needed.Herein,a series of Ru(II)polypyridine complex-based PSs,RuNMe,RuH,and RuCN,were synthesized,and their applications against hypoxic tumor cells through PDT were investigated.All three complexes showthe ability to generate the superoxide anion radical(·O_(2)^(-)),which is the type I photoreaction and less O_(2)^(-)dependent.RuNMe shows the best PDT performance against MCF-7 cells and three-dimensional multicellular spheroids,due to its higher cellular uptake and more reactive oxygen species generation.More importantly,RuNMe-incubated MCF-7 cells show photoinduced ferroptosis as evidenced by glutathione peroxidase 4 downregulation and lipid peroxide accumulation.This work not only develops a novel ferroptosis-inducing Ru(II)complex with the type I PDT process but also offers an effective strategy to solve tumor hypoxia in PDT.
文摘The polarographic catalytic wave of oxygen reduction caused by mefenamic acid (MA) with redox properties was reported in this paper. The electrochemical process of the catalytic wave was proposed that the superoxide anion O(?) was generated polarographically and the dismutation of the O(?) was catalyzed by MA to reproduce O_2 and H_2O_2. This explained chemically the scavenging of the O_2^- by MA im biomedical area. Based on the catalytic wave, a new method for the determination of MA by single-sweep polarography was developed.
