Abstract
The occurrence of dementia, such as during Alzheimer’s disease, has grown with increasing average age in human society. We currently have very limited options in terms of medicines that symptomatically delay the development of dementia in early stages without curing the disease. In the past few decades, while several pharmaceutical companies have taken up the challenge of developing such medicines, candidate drugs have typically failed to show the expected therapeutic effects in humans, presumably because of their low efficiency of distribution to the brain. We have recently developed the strategy to effectively deliver the new candidate peptide drugs, such as insulin and GLP-1 receptor agonist (Exendin-4), for treatment of dementia via intranasal administration. Nasal administration is currently considered an ideal route for delivering drugs to the central nervous system by bypassing the blood-brain barrier. We demonstrated that nasal coadministration of peptide drugs with CPPs can accelerate their nose-to-brain transport and improve or prevent the cognitive dysfunction in the senescence-accelerated mouse. Thus, our study suggests that nose-to-brain delivery of insulin and exendin-4 via coadministration with CPP shows promise for the treatment of cognitive dysfunction in dementia.
