RESUMO
The blood-brain barrier (BBB) is a major limiting factor that prevents the treatment of Parkinson's disease (PD). In the present study, MgOp@PPLP nanoparticles are explored by using MgO nanoparticles as a substrate, polydopamine as a shell, wrapping anti-SNCA plasmid inside, and modifying polyethylene glycol, lactoferrin, and puerarin on the surface to improve the hydrophilicity, brain targeting and antioxidant properties of the particles, respectively. MgOp@PPLP exhibits superior near-infrared radiation (NIR) response. Under the guidance of photothermal effect, these MgOp@PPLP particles are capable of penetrating the BBB and be taken up by neuronal cells to exert gene therapy and antioxidant therapy. In both in vivo and in vitro models of PD, MgOp@PPLP exhibits good neuroprotective effects. Therefore, combined with noninvasive NIR radiation, MgOp@PPLP nanoplatform with good biocompatibility becomes an ideal material to combat neurodegenerative diseases.
Assuntos
Barreira Hematoencefálica , Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológicoRESUMO
DNA G4-structures from human c-MYC promoter and telomere are considered as important drug targets; however, the developing of small-molecule-based fluorescent binding ligands that are highly selective in targeting these G4-structures over other types of nucleic acids is challenging. We herein report a new approach of designing small molecules based on a non-selective thiazole orange scaffold to provide two-directional and multi-site interactions with flanking residues and loops of the G4-motif for better selectivity. The ligands are designed to establish multi-site interactions in the G4-binding pocket. This structural feature may render the molecules higher selectivity toward c-MYC G4s than other structures. The ligand-G4 interaction studied with 1H NMR may suggest a stacking interaction with the terminal G-tetrad. Moreover, the intracellular co-localization study with BG4 and cellular competition experiments with BRACO-19 may suggest that the binding targets of the ligands in cells are most probably G4-structures. Furthermore, the ligands that either preferentially bind to c-MYC promoter or telomeric G4s are able to downregulate markedly the c-MYC and hTERT gene expression in MCF-7 cells, and induce senescence and DNA damage to cancer cells. The in vivo antitumor activity of the ligands in MCF-7 tumor-bearing mice is also demonstrated.
Assuntos
Antineoplásicos/química , Neoplasias da Mama , Quadruplex G , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Desenho de Fármacos , Feminino , Genes myc , Humanos , Ligantes , Células MCF-7 , Camundongos , Regiões Promotoras Genéticas , TelômeroRESUMO
Subunit vaccines derived from tumor antigens play a role in tumor therapy because of their unique advantages. However, because of the weak immunogenicity of peptides in subunit vaccines, it is difficult to trigger an effective cytotoxic T lymphocyte (CTL) response, which is critical for cancer therapy. A requirement for the activation of CTL cells by exogenous antigens is the stimulation of antigen presenting cells (APC) with the help of adjuvants and cross-presentation to T lymphocytes. Standard nonconjugated adjuvant-peptide mixtures do not ensure co-targeting of the antigen and the adjuvant to the same APC, which limits the effects of adjuvants. In this study, a fusion protein consisting of murine granulocyte-macrophage colony stimulating factor (mGM-CSF) fused with CTA2 (A2 subunit of cholera toxin) was generated and assembled with CTB-PSMA624-632 (prostate specific membrane antigen (PSMA) peptide 624-632 fused to CTB) to obtain a cholera toxin-like protein. The chimeric protein retained the biological activity of mGM-CSF and had stronger GM1 binding activity than (CTB-PSMA624-632)5. C57BL/6J mice immunized with the CT-like chimeric protein exhibited delayed tumor growth following challenge with human PSMA-EGFP-expressing RM-1 cells. Experiment results showed that the CT-like chimeric protein could induce the maturation of DC cells and improve CTL responses. Overall, these results indicate that the nasal administration of a CT-like chimeric protein vaccine results in the development of effective immunity against prostate tumor cells and might be useful for future clinical anti-tumoral applications.