Visualization and Quantitative Assessment of the Brain Distribution of Insulin through Nose-to-Brain Delivery Based on the Cell-Penetrating Peptide Noncovalent Strategy
Abstract
Our recent work suggested that intranasal coadministration with the cell-penetrating peptide (CPP) penetratin increased the brain distribution of the peptide drug insulin. The present study aimed to distinctly certify the ability of penetratin to facilitate the nose-to-brain delivery of insulin by quantitatively evaluating the distribution characteristics in brain using radioactive (64)Cu-NODAGA-insulin. Autoradiography and analysis using a gamma counter of brain areas demonstrated that the accumulation of radioactivity was greatest in the olfactory bulb, the anterior part of the brain closest to the administration site, at 15 min after intranasal administration of (64)Cu-NODAGA-insulin with l- or d-penetratin. The brain accumulation of (64)Cu-NODAGA-insulin with penetratin was confirmed by ELISA using unlabeled insulin in which intact insulin was delivered to the brain after intranasal coadministration with l- or d-penetratin. By contrast, quantification of cerebrospinal fluid (CSF) samples showed increased insulin concentration in only the anterior portion of the CSF at 15 min after intranasal coadministration with l-penetratin. This study gives the first concrete proof that penetratin can accelerate the direct transport of i...Continue Reading
References
Brain uptake of the glucagon-like peptide-1 antagonist exendin(9-39) after intranasal administration
Citations
Related Concepts
Related Feeds
CSF & Lymphatic System
This feed focuses on Cerebral Spinal Fluid (CSF) and the lymphatic system. Discover the latest papers using imaging techniques to track CSF outflow into the lymphatic system in animal models.