Red grapes may help the digestive system protect itself from colitis, which is inflammation of the colon.
A new study suggests that everyday red table grapes contain tiny particles that allow stem cells in the intestine to continue to function and reproduce, even as colitis is introduced. These intestinal stem cells are typically damaged in colitis.
Researchers say it’s the first time these types of particles have been identified in an edible plant. Until now, they’ve been found only in mammals.
If further studies confirm these results, they say it could lead to new, safer, and more economical treatments for colitis by using edible plant-derived substances to deliver medicines to the intestines or as a medicine themselves.
Experts caution that these are only early findings from research involving mice, but the notion is promising.
“It’s very intriguing to recognize certain elements in our food that may in fact be protective and support the cells in our colon that are responsible for reproduction in mice models,” said David T. Rubin, MD, a professor of medicine and co-director of the Inflammatory Bowel Disease Center at University of Chicago Medicine.
Why Stem Cells Matter in Colitis
In the study, published in the journal Molecular Therapy, researchers looked at how grape exosome-like nanoparticles (GELNs) — tiny particles seen only with an electron microscope — affected intestinal stem cells in mice.
Exosomes are specialized nanoparticles that are released by many types of cells. Recent research has suggested that these particles play an important role in stem cell formation. Stem cells themselves are unspecialized cells that have the potential to develop into many different types of cells in the body. They also work as a repair system for the body and replicate to replenish other cells when needed.
This self-renewal process is critical to protecting people from disease. For example, the lining of the intestine, the epithelium, sloughs off and renews itself regularly in healthy people, and the process is driven by stem cells within the intestine. But in people with colitis, this process doesn’t work properly, and the intestine becomes damaged.
How Grapes May Help Colitis
For the study, researchers fed one group of laboratory mice the grape substance while another group of mice acted as a control group and did not receive the GELNs. Colitis was then chemically induced in both groups over the course of several days.
The results showed that, within 13 days, all of the mice in the control group died, but the mice that received the grapes lived almost twice as long (25 days).
Researchers also colored the GELNs with fluorescent dye so they could see how they passed through the intestinal tract. They found that the grape particles stayed about 12 hours longer in the small intestine than the large intestine.
The results suggest that grape nanoparticles help protect against damage to the intestine by penetrating the epithelium and being taken up by mouse intestinal stem cells. This allows them to continue to function normally when threatened by colitis.
Dr. Rubin said that while the results of the study are certainly encouraging, the findings have a long way to go before they can translate to human therapies. “It doesn’t mean everyone should go on a red grape diet,” he said.