Stabilizing effect of small concentrations of PAMAM dendrimers at the insulin aggregation

Dendrimers’ action on proteins and peptides has a dual and controversial character. On one hand, they dissolve prion protein and amyloid fibrils aggregates, which are otherwise only soluble in solvents containing both detergents and high denaturant concentrations. On the other hand they are able to destabilize proteins in generation dependent manner. In present work we estimated the influence of small concentrations (up to 1.4 μg/ml) of cationic, neutral and anionic poly(amidoamine) dendrimers of 3rd and 4th generations on dithiotreitol induced aggregation of insulin. It was found that cationic dendrimers decreased the insulin aggregation, while anionic and neutral ones did not. At the same time, destabilizing effect of dendrimers on insulin structure was not observed. The conclusion was made that small concentrations of dendrimers can be applied to prevent or decrease the formation of misfolded structures of protein.