Mitochondria are identified as a valuable target for cancer therapy owing to their primary function in energy supply and cellular signal regulation. Mitochondria in tumor cells are depicted by excess reactive oxygen species (ROS), which lead to numerous detrimental results. Hence, mitochondria-targeting ROS-associated therapy is an optional therapeutic strategy for cancer. In this contribution, a light-induced ROS generator (TBTP) is developed for evaluation of the efficacy of mitochondria-targeting ROS-associated therapy and investigation of the mechanism underlying mitochondrial-injure-mediated therapy of tumors. TBTP serves as an efficient ROS generator with low cytotoxicity, favorable biocompatibility, excellent photostability, mitochondria-targeted properties, and NIR emission. In vivo and in vitro experiments reveal that TBTP exhibits effective anticancer potential. ROS generated from TBTP could destroy the integrity of mitochondria, downregulate ATP, decrease the mitochondrial membrane potential, secrete Cyt-c into cytoplasm, activate Caspase-3/9, and induce cell apoptosis. Moreover, RNA-seq analysis highlights that an ROS burst in mitochondria can kill tumor cells via inhibition of the AKT pathway. All these results prove that mitochondrial-targeted ROS-associated therapy hold great potential in cancer therapy.
Anni Cui,Ying Bao,Haitao Xu,Xin Mu,Xiahua Zhong,Wynn Wee,Fanqi Wu,Guiye Shan
The rapid emergence of drug-resistant bacteria has attracted great attention to exploring advanced antibacterial methods. However, single-modal antibacterial therapy cannot easily eliminate drug-resistant bacteria completely due to its low efficacy. Therefore, it is essential to achieve multi-modal antibacterial therapy effectively. Herein, a dual-modal ROS generator was designed based on photosensitive PDA–MnO2@Ce6/liposome (PMCL) nanozymes for synergistic chemo-photodynamic therapy. PMCL nanozymes adhere to bacteria through liposome–membrane fusion. Meanwhile, PMCL catalyzes endogenous hydrogen peroxide (H2O2) to generate hydroxyl radicals (˙OH) and singlet oxygen (1O2) under laser irradiation. Furthermore, the photothermal effect can accelerate the generation of ROS. Based on dual-enzyme activities (mimicking peroxidase and catalase) and photodynamic properties, PMCL achieves powerful antibacterial efficacy and mature bacterial biofilm eradication. With the synergistic chemo-photodynamic effects, bacterial populations decrease by >99.76% against Gram-positive S. aureus and Gram-negative E. coli. Notably, the synergistic antibacterial properties of PMCL nanozymes are further explored using a mouse wound model of S. aureus infection. This work fabricated an efficient dual-modal ROS generator to kill bacteria, further providing a new strategy for treating wound infection.