ABSTRACT
This work introduces a new fibrous system for synergistic cancer therapy. The system consists of poly(d,l-lactic-co-glycolic acid) (PLGA) fibers with a core encapsulating an anticancer drug and a shell entrapping gold nanorods (AuNRs) as a photothermal agent. On exposure to NIR light, the photothermal agent generates heat to raise the local temperature of the fibers. If the temperature is above a glass transition (Tg) of the polymer, the polymer chains will be mobile, increasing free volume in size within the shell. As a result, a rapid release of the drug can be achieved. When NIR light is turned off, the release will stop with inactivity of the photothermal agent, followed by freezing the segmental motion of the polymer chains. The on-off switching of NIR light in a time-controllable manner allows a repeated and accurate release of the drug, leading to the significant enhancement of anticancer activity in combination with the hyperthermia effect arising from the photothermal agent.
Subject(s)
Antibiotics, Antineoplastic/pharmacology , Delayed-Action Preparations , Doxorubicin/pharmacology , Drug Delivery Systems/methods , Metal Nanoparticles/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Antibiotics, Antineoplastic/chemistry , Cell Death/drug effects , Cell Line, Tumor , Cetrimonium/chemistry , Doxorubicin/chemistry , Drug Compounding/methods , Drug Liberation , Electrochemical Techniques , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Epithelial Cells/pathology , Epithelial Cells/radiation effects , Female , Gold/chemistry , Humans , Hyperthermia, Induced/methods , Infrared Rays , Kinetics , Low-Level Light Therapy/methods , Metal Nanoparticles/ultrastructure , Nanotubes/chemistry , Nanotubes/ultrastructureABSTRACT
Due to inadequate efficacy of antidepressants, various new chemical entities and agents of natural origin have been tested for therapeutic efficacy both alone and to augment existing antidepressants, producing varied clinical results. This article summarizes the basic properties of curcumin and its mechanisms of action, with specific emphasis on the etiopathogenesis of depression, preclinical and current clinical evidence, and future research directions, to better understand the possible role of curcumin in treating depression. Curcumin may have antidepressant activities with diverse mechanisms of action involving primarily neurotransmitters, transcription pathways, neurogenesis, the hypothalamic-pituitary-adrenal axis and inflammatory and immune pathways, as demonstrated in various animal and human studies. Current published randomized clinical trials suggest a small, non-significant benefit of curcumin for major depression. More adequately-powered and methodologically improved studies are mandatory.