Researchers at UC Riverside are pioneering breakthrough research that may substantially benefit the way medicine is taken for diabetes and cancer patients. Needles and injections could be old news as patients may find themselves taking pills instead to manage their conditions. The details of this, and demonstrations of its effectiveness, are described in a new Journal of the American Chemical Society paper.

UCR scientists have created a chemical “tag” that can be added to these drugs, allowing them to enter blood circulation via the intestines. This is necessary due to how most drugs for these diseases dissolve in water, so transporting them through the intestines was unfortunately not feasible and these drugs, prior to this research, could not be administered orally. 

Min Xue, a UCR chemistry professor, led the research on the tag, which is composed of a small peptide or a short chain of amino acids. Peptides are similar to protein fragments in that a protein is a long chain of amino acids. Xue explained, “Because they are relatively small molecules, you can chemically attach them to drugs, or other molecules of interest, and use them to deliver those drugs orally.”

Xue’s laboratory was conducting unrelated tests and experiments when researchers observed these peptides making their way into cells. “We did not expect to find this peptide making its way into cells. It took us by surprise,” stated Xue in regards to the discovery. “We always wanted to find this kind of chemical tag, and it finally happened serendipitously.”

This observation was unexpected, as previously, the researchers believed that this type of delivery tag needed to carry positive charges to be accepted into the negatively charged cells. Their work with this neutral peptide tag, called EPP6, shows that belief was not accurate. As such, EPP6 can transport a wide array of small-molecule cargos, including medicines, into a diverse panel of animal cells.

To test how the peptide moved and performed throughout the body, Xue’s research group teamed up with Kai Chen’s group from the University of Southern California’s Keck School of Medicine. They fed the peptide to mice and using a PET scan, a functional imaging technique that provides an image similar to a whole-body X-ray, the team observed the peptide accumulating in the intestines, and documented its transfer into the animals’ organs via the blood. 

With the tag having proved successful in entering and navigating the circulatory systems through oral administration, the research team plans on demonstrating and testing their discovery on a selection of drugs. Drugs such as insulin must be injected and can often be costly in today’s pharmaceutical market. The researchers are hopeful their future experiments can bring much needed change to this issue, allowing them to add this tag to a wide variety of drugs and chemicals, changing the way those molecules move through the body.  “This discovery could lift a burden on people who are already burdened with illness,” Xue said.

The need to develop molecularly well-defined tags is ever-increasing. It may ultimately enable commonly taken medicine to be administered orally as opposed through intravenous means which involves injections. Xue has expressed her bright vision of the future explaining, “Quite compelling preliminary results make us think we can push this further.”