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In recent years, aggregation-induced emission luminogens (AIEgens) have been widely developed for bio-imaging, theranostics, organic photoelectronics, and chemo/biosensors. While, the existing AIEgens are almost all obtained by organic synthesis, experiencing complicated synthesis routes, high cost, environmentally unfriendly, and poor biocompatibility. Therefore, exploration of AIEgens from natural products is an attractive alternative approach. In this contribution, two natural AIE-active materials, Tangeretin and Nobiletin, were found, which can be extracted from orange peel. Single crystal structure, fluorescence spectra and viscosity analyses verified that restriction of intramolecular rotation was responsible for the AIE phenomenon of Tangeretin and Nobiletin. The theoretical calculation results indicated that the intermolecular charge transfer (ICT) was related with the bathochromic-shift in the solid-state. Moreover, Tangeretin and Nobiletin were biocompatible and could selectively target lysosomes. In short, these natural products provided a new approach for obtaining new kinds of AIEgens, and showing great potential in bioimaging. • Two poly(methoxy)flavone (tangeretin and nobiletin) were extracted from orange peel. • Tangeretin and nobiletin have excellent aggregation-induced emission properties. • The results show that both tangeretin and nobiletin can effectively locate in lysosomes. [ABSTRACT FROM AUTHOR]

Tumor cells intensively engage in metabolic reprogramming for enhancing the availability of glycolytic metabolites and support cell proliferation. As the most important rate-limiting enzyme in aerobic glycolysis, activating the pyruvate kinase muscle isoform 2 (PKM2) from dimers to tetramers has become a key tumor chemotherapy method to control glucose metabolism. Herein, we developed a glycopeptide-based PKM2 nano-activator, which could induce the tetramerization of PKM2 based on serine bonding to Domain C of PKM2. The bound and trapped PKM2 tetramers significantly hindered glycolytic intermediates, prevented the nucleus translocation of dimeric PKM2, and ultimately inhibited the proliferation, chemoresistance and metastasis of tumor. The glycopeptide assembled into nanoparticles under aqueous conditions and in the circulation, which in situ transformed into PKM2 nano-activator with nanofibrillar structure after specifically activated by O-GlcNAcase recognition upregulated in a wide range of human tumors. Moreover, the glycopeptide-based PKM2 nano-activator successfully accumulated at the tumor sites and boosted the chemo-drug sensitivity against prostate and breast cancers. Attributed to these intriguing results, the newly developed glycopeptide-based PKM2 nano-activator can be envisioned a promising candidate for the treatment of tumors by switching catabolic pathways. Schematic illustration of self-assembly, accumulation and in situ fibrillar transformation of GPNA1 in tumor cells, followed by intracellular anti-proliferative events. [Display omitted] [ABSTRACT FROM AUTHOR]