Insulin-cell penetrating peptide hybrids with improved intestinal absorption efficiency

Abstract: Cell-penetrating peptide (CPP) was linked to insulin to form insulin–CPP hybrids. The intestinal absorption efficiency of CPP hybridized insulin was 6–8 times increased compared to normal insulin as tested on Caco-2 cell monolayer, a widely used in vitro model for intestinal absorption. Insulin–CPP hybrid transportation seemed to be through an active and transcytosis-like mechanism. Importantly, insulin in hybrids kept intact after they passed through the Caco-2 cell monolayer. This study provides a new clue for oral insulin development. [Copyright &y& Elsevier]