2 research outputs found
Dissecting the Molecular Mechanism of Apoptosis during Photothermal Therapy Using Gold Nanoprisms
The photothermal response of plasmonic nanomaterials can be exploited for a number of biomedical applications in diagnostics (biosensing and optoacoustic imaging) and therapy (drug delivery and photothermal therapy). The most common cellular response to photothermal cancer treatment (ablation of solid tumors) using plasmonic nanomaterials is necrosis, a process that releases intracellular constituents into the extracellular milieu producing detrimental inflammatory responses. Here we report the use of laser-induced photothermal therapy employing gold nanoprisms (NPRs) to specifically induce apoptosis in mouse embryonic fibroblast cells transformed with the SV40 virus. Laser-irradiated “hot” NPRs activate the intrinsic/mitochondrial pathway of apoptosis (programmed cell death), which is mediated by the nuclear-encoded proteins Bak and Bax through the activation of the BH3-only protein Bid. We confirm that an apoptosis mechanism is responsible by showing how the NPR-mediated cell death is dependent on the presence of caspase-9 and caspase-3 proteins. The ability to selectively induce apoptotic cell death and to understand the subsequent mechanisms provides the foundations to predict and optimize NP-based photothermal therapy to treat cancer patients suffering from chemo- and radioresistance
Effect of Surface Chemistry and Associated Protein Corona on the Long-Term Biodegradation of Iron Oxide Nanoparticles In Vivo
The protein corona
formed on the surface of a nanoparticle in a biological medium determines
its behavior in vivo. Herein, iron oxide nanoparticles containing
the same core and shell, but bearing two different surface coatings,
either glucose or poly(ethylene glycol), were evaluated. The nanoparticles’
protein adsorption, in vitro degradation, and in vivo biodistribution
and biotransformation over four months were investigated. Although
both types of nanoparticles bound similar amounts of proteins in vitro,
the differences in the protein corona composition correlated to the
nanoparticles biodistribution in vivo. Interestingly, in vitro degradation
studies demonstrated faster degradation for nanoparticles functionalized
with glucose, whereas the in vivo results were opposite with accelerated
biodegradation and clearance of the nanoparticles functionalized with
poly(ethylene glycol). Therefore, the variation in the degradation
rate observed in vivo could be related not only to the molecules attached
to the surface, but also with the associated protein corona, as the
key role of the adsorbed proteins on the magnetic core degradation
has been demonstrated in vitro