TechConnectWorld 2011 Conference and Expo TechConnect World 2011 Nanotech 2011 Clean Technology 2011 Microtech 2011 Bio Nanotech 2011 TechConnect Summit and Expo 2011

Mechanistic studies of in vitro cytotoxicity of PAMAM dendrimers in mammalian cells

S.P. Mukherjee, F.M. Lyng, A. Garcia, M. Davoren, H.J. Byrne
Focas Research Institute, Dublin Institute of Technology, IE

Keywords: PAMAM dendrimers, cytotoxicity, EC50 correlation, ROS, mitochondrial membrane potential, proton-sponge effect, lysosomal activity, caspase activation, apoptosis, DNA damage


The in vitro cytotoxic response of human dermal and colon cell lines to structurally well-defined full generation cationic dendritic polyamidoamine (PAMAM) nanoparticles of generations G4, G5, G6 was investigated. PAMAM dendrimers have been demonstrated to elicit a well defined cytotoxicological response from Alamar Blue, Neutral Red and MTT assays, where the response increases systematically with dendrimer generation and number of surface amino groups. A good correlation was found between the EC50 values of these assays. This systematic response is furthermore demonstrated for the generation of reactive oxygen species, mitochondrial membrane potential, inflammatory responses, lysosomal activity, caspase activation, apoptosis and DNA damage. The mechanism of endosomal escape of PAMAM by the so-called ‘proton-sponge effect’ was also studied. The results are consistent with a pathway of endosomal uptake of PAMAM, followed by endosomal rupture and subsequent localisation of PAMAM dendrimers in the mitochondria, leading to PAMAM generation, dose and time dependant biphasic ROS production and caspase- 8 and 3 activation, inflammatory responses (TNF-α, IL-6 and IL-8 expression), apoptosis and DNA damage. Overall, significant differences are observed between the responses of the dermal and colon cell lines, and it is suggested that these can be understood in terms of differing intrinsic antioxidant levels.
Sessions Monday Tuesday Wednesday Thursday Authors Keywords Affiliations Search

TechConnect World 2011 Nanotech 2011 Clean Technology 2011 Microtech 2011 BioNanotech 2011 TechConnect Summit 2011
2011 Events | Program | Speaker | Short Courses Sponsor Exhibit/Showcase Press Venue Register
Subscribe | Contact | Site Map
© Copyright 2010 TechConnect World. All Rights Reserved.