Colombo Alessia, Fontani Mattia, Dragonetti Claudia, Roberto Dominique, Williams J A Gareth, Scotto di Perrotolo Rossella, Casagrande Francesca, Barozzi Sara, Polo Simona
Dipartimento di Chimica, dell'Università degli Studi di Milano, and UdR INSTM di Milano, via Golgi 19, 20133, Milan, Italy.
Department of Chemistry, Durham University, Durham, DH1 3LE, UK.
Chemistry. 2019 Jun 12;25(33):7948-7952. doi: 10.1002/chem.201901527. Epub 2019 May 13.
Curcumin has chemopreventative properties against a variety of tumours, but has poor bioavailability. Here, two new bis-cyclometallated iridium(III) complexes have been prepared, featuring the natural product curcumin (CUR) or its reduced form, tetrahydrocurcumin (THC), as bidentate, anionic O O-binding ligands. The iridium THC complex is highly luminescent in deoxygenated solution and efficiently generates singlet oxygen under aerated conditions, whereas in the CUR analogue, other non-radiative decay pathways are competitive. The complexes are rapidly taken up by a variety of human tumour cell lines from solutions of micromolar concentration. They show negligible cytotoxicity in the absence of irradiation. When briefly irradiated with visible light, Ir-THC becomes highly phototoxic, inducing rapid apoptosis within 2 h. The results show the high potential of such complexes as sensitizers in photodynamic therapy (PDT).
姜黄素具有针对多种肿瘤的化学预防特性，但生物利用度较差。在此，制备了两种新型双环金属化铱（III）配合物，其特征在于天然产物姜黄素（CUR）或其还原形式四氢姜黄素（THC）作为双齿阴离子O O结合配体。铱-THC配合物在脱氧溶液中具有高发光性，在曝气条件下能有效产生活性单线态氧，而在CUR类似物中，其他非辐射衰变途径具有竞争性。这些配合物能从微摩尔浓度的溶液中被多种人类肿瘤细胞系快速摄取。在无辐照情况下，它们显示出可忽略不计的细胞毒性。当用可见光短暂照射时，Ir-THC会变得具有高光毒性，在2小时内诱导快速凋亡。结果表明这类配合物作为光动力疗法（PDT）中的敏化剂具有很高的潜力。
