Gayathry Morvil, Chia Cheng Yi Andrew, Tang Hock Chun, Kim Chu Young,
Sathya Dev. Unudurthi
Cell penetrating peptides (CPPs) are a relatively new innovation introduced to the drug development industry. The ability of these peptides in translocating otherwise impermeable agents across the cell membrane has attracted world-wide attention . In drug development, impermeable agents are drug molecules that have low cell permeability on its own. Thus, CPPs hold great potential as in vitro and in vivo delivery vectors for use in research and medicine. However, because CPPs are susceptible to degradation by digestive proteases when taken orally, they have not been successfully used as delivery vectors so far. This restricts the use of CPPs for in vivo purposes. Hence, it will be useful to develop CPPs which are resistant to digestive proteases, as this would widen the application scope of CPPs. We present a novel CPP derived from wheat, called α-1-g, which efficiently translocates impermeable agents across the cell membrane even after being exposed to digestive proteases. We conducted confocal microscopy studies to visually compare the cell penetration activity of α-1-g, and TAT under the physiological condition. Our results indicate that α-1-g is at least 15-fold more effective than TAT when used after exposure to digestive proteases. Therefore α-1-g can be used for in vivo applications such as oral delivery of pharmaceutical agents.