Targeting Alzheimer's disease with multimodal polypeptide-based nanoconjugates

Alzheimer's disease (AD), the most prevalent form of dementia, remains incurable mainly due to our failings in the search for effective pharmacological strategies. Here, we describe the development of targeted multimodal polypeptide-based nanoconjugates as potential AD treatments. Treatment with polypeptide nanoconjugates bearing propargylamine moieties and bisdemethoxycurcumin or genistein afforded neuroprotection and displayed neurotrophic effects, as evidenced by an increase in dendritic density of pyramidal neurons in organotypic hippocampal culture. The additional conjugation of the Angiopep-2 targeting moiety enhanced nanoconjugate passage through the blood-brain barrier and modulated brain distribution with nanoconjugate accumulation in neurogenic areas, including the olfactory bulb. Nanoconjugate treatment effectively reduced neurotoxic β amyloid aggregate levels and rescued impairments to olfactory memory and object recognition in APP/PS1 transgenic AD model mice. Overall, this study provides a description of a targeted multimodal polyglutamate-based nanoconjugate with neuroprotective and neurotrophic potential for AD treatment.

Polyornithine-based polyplexes to boost effective gene silencing in CNS disorders

Gene silencing therapies have successfully suppressed the translation of target proteins, a strategy that holds great promise for the treatment of central nervous system (CNS) disorders. Advances in the current knowledge on multimolecular delivery vehicles are concentrated on overcoming the difficulties in delivery of small interfering (si)RNA to target tissues, which include anatomical accessibility, slow diffusion, safety concerns, and the requirement for specific cell uptake within the unique environment of the CNS. The present work addressed these challenges through the implementation of polyornithine derivatives in the construction of polyplexes used as non-viral siRNA delivery vectors. Physicochemical and biological characterization revealed biodegradability and biocompatibility of our polyornithine-based system and the ability to silence gene expression in primary oligodendrocyte progenitor cells (OPCs) effectively. In summary, the well-defined properties and neurological compatibility of this polypeptide-based platform highlight its potential utility in the treatment of CNS disorders.