A group of researchers from the "Regenerative Medicine Program" of the Bellvitge Biomedical Research Institute (IDIBELL), in L'Hospitalet de Llobregat (Barcelona) -known as RegenBell-, has carried out a study in which it demonstrates that injuries in the intestine leave a lasting mark that drives and accelerates tissue regeneration.
The study, publicized in the specialized journal "Nature Communications" and led by the member of the Center for Biomedical Research in Network for Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Jordi Guiu, has focused on the repair process following inflammatory damage and has shown that intestinal epithelial cells have a memory mechanism capable of preserving a molecular recollection of prior injuries.
In this context, the authors emphasize that the analyzed organ "has extraordinary regenerative capacity," since "each day, millions of cells from its surface renew themselves to maintain an essential barrier for health." "This constant renewal process is especially important because the intestine is continuously exposed to mechanical stress, food, the microbiota and, on some occasions, to inflammatory processes that can damage its tissues," they have detailed.
They also recall that "in inflammatory bowel diseases, such as Crohn's disease or ulcerative colitis, these lesions can occur repeatedly over time," which forces the intestine "to activate, again and again, repair and regeneration mechanisms." Based on this premise, the work has made it possible to verify that inflammatory episodes leave a persistent imprint in intestinal cells that enables a much faster and more effective response to subsequent damage. "Essentially, it could be said that they retain information from previous experiences, learn from them, and adapt their regenerative response to optimize it to the maximum," the researchers stated.
A biological memory that prepares the intestine
"This means that the intestine is not exactly the same again after an injury," Guiu said, explaining that "the cells retain a molecular imprint of the inflammation that modifies their behavior and prepares them to better face future injuries," a conclusion reached after using experimental models of intestinal damage and studying, cell by cell, what happens during the tissue recovery phase.
The results show that, even when the inflammation has subsided and the intestine appears to be completely repaired, the cells maintain changes in their gene activity and in the structure of their DNA. This molecular imprint acts as a reminder of the prior aggression and has functional effects: in the animal models analyzed, those that had suffered an initial injury regenerated more quickly when faced with a second injury.
"This is not a memory in the usual sense of the term, but a biological memory that is imprinted in the cells' genetic material," Guiu has specified, adding that "it is as if the cells had learned from the previous experience".
The work has also managed to identify a key molecule in the establishment of this memory: interferon gamma, traditionally associated with inflammatory responses. When the research team blocked its function, much of the regenerative advantages acquired after the first injury disappeared. With these data, the authors reinforce the hypothesis that "inflammation is not only a transient response to damage," but that "it can also remodel tissues in a lasting way and influence future responses".