Abstract：
Curcumin (CUR), a natural compound extracted from turmeric, has shown potential as a photosensitizer in photodynamic therapy (PDT). The aim of this work was to enhance the efficacy of CUR by modifying it using titanium dioxide (TiO2) nanoparticles and a cationic polymer called Sofast to create a nanocomposite TiO2-CUR-Sofast (TCS). Compared to unmodified CUR, TCS exhibited a broadening toward longer wavelength in the absorption wavelength within the 400-550 nm range, leading to improved CUR absorption. Cellular uptake efficiency of TCS was also enhanced, and it demonstrated nearly 4.7-fold higher reactive oxygen species (ROS) generation than CUR. Furthermore, TCS displayed the ability to attach to the cell membrane and enter cells within a 30-min incubation period. Upon irradiation, TCS exhibited remarkable cytotoxicity, resulting in a significant reduction in the viability of various cancer cells. Autofluorescence lifetime imaging of intracellular reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD) enzymes indicated that cancer cells treated with TCS and irradiation undergo a metabolic pathway shift from oxidative phosphorylation to glycolysis. These findings highlight the potential of TCS as an effective PDT agent for cancer treatment.
摘要：
姜黄素(CUR),从姜黄中提取的天然化合物，在光动力疗法（PDT）中显示出作为光敏剂的潜力。这项工作的目的是通过使用二氧化钛（TiO2）纳米颗粒和称为Sofast的阳离子聚合物对CUR进行改性，以创建纳米复合材料TiO2-CUR-Sofast（TCS）来增强CUR的功效。与未经修改的CUR相比，TCS在400-550nm范围内的吸收波长中表现出向更长波长的加宽，导致提高CUR吸收。TCS的细胞摄取效率也得到增强，它显示出活性氧（ROS）的产生比CUR高近4.7倍。此外，TCS显示出附着在细胞膜上并在30分钟的孵育期内进入细胞的能力。照射后，TCS表现出显著的细胞毒性，导致各种癌细胞的活力显着降低。细胞内还原的烟酰胺腺嘌呤二核苷酸（磷酸）（NAD（P）H）和黄素腺嘌呤二核苷酸（FAD）酶的自发荧光寿命成像表明，用TCS和辐射处理的癌细胞经历了从氧化磷酸化到糖酵解的代谢途径转变。这些发现强调了TCS作为癌症治疗的有效PDT药物的潜力。
