New Rat Model Replicates Creeping Fat in Crohn’s Disease, Offering Hope for New Therapies
Researchers at the Germans Trias i Pujol Research Institute (IGTP) and the Institut de Recerca Biomèdica Catalunya Sud (IRB CatSud) have developed a new experimental rat model that mimics key characteristics of creeping fat, a hallmark of Crohn’s disease. This advancement, published in the journal Inflammatory Bowel Diseases, could significantly aid in understanding the role of this tissue in disease progression and identifying potential new treatments.
Understanding Creeping Fat and Crohn’s Disease
Crohn’s disease is a chronic inflammatory bowel disease (IBD) that can affect any part of the gastrointestinal tract. Creeping fat, also known as mesenteric fat, is the accumulation of adipose tissue around inflamed sections of the intestine. It’s not merely a passive consequence of inflammation; research indicates it’s an active tissue involved in the disease process.
The New Experimental Model
The study utilized a colitis model induced in rats using 2,4,6-trinitrobenzenesulfonic acid (TNBS). Researchers found that this model developed mesocolic adipose tissue hyperplasia – an increase in the size of fat cells – that shared macroscopic, histological, immunological, and molecular similarities with creeping fat observed in human Crohn’s disease patients.
Dr. Laura Clua, the first author of the study, explained that the model demonstrates creeping fat as a “metabolically and immunologically active tissue,” exhibiting significant immune cell infiltration and elevated levels of pro-inflammatory cytokines, mirroring observations in patients. [3]
Key Findings and Connections to Human Disease
The research revealed a correlation between the severity of intestinal inflammation and the development of mesocolic hyperplasia. Importantly, the study also found evidence of bacterial translocation – the movement of bacteria from the gut into the surrounding tissues – to the subserosa. This supports the hypothesis that the gut microbiota may play a role in the remodeling of mesenteric adipose tissue. [3]
Approximately half of the animals in the study developed mesocolic hyperplasia with features comparable to creeping fat in Crohn’s disease. [3]
Implications for Future Research
Dr. Carolina Serena, leader of the Inflammatory Bowel Diseases research group (IBODI) at IRB CatSud, believes this model will be invaluable for further investigating the mechanisms underlying the disease. “Having an experimental model that reproduces this phenomenon facilitates the study of the relationship between intestinal inflammation, bacterial translocation and remodeling of mesenteric adipose tissue,” she stated.
Dr. Josep Manyé, a researcher in the Inflammatory Bowel Diseases Research Group (GReMII) at IGTP, added that this type of model could lead to a better understanding of creeping fat’s role in Crohn’s disease and potentially pave the way for new therapeutic strategies. [1]
Collaborative Research Effort
The study involved researchers from several institutions, including Hospital Universitari Germans Trias i Pujol, Viladecans Hospital, CIBEREHD, and various teams within IGTP, such as the High-Content Genomics and Bioinformatics facility and the Translational Research in Hepatic Diseases group.
Looking Ahead
This new rat model offers a reproducible platform for studying mesenteric adipose tissue in inflammatory bowel disease and evaluating potential therapeutic interventions in preclinical research. The findings contribute to a growing body of knowledge about the complex interplay between inflammation, the gut microbiome, and adipose tissue in the development and progression of Crohn’s disease.
Publication: Laura Clua et al, Characterization of mesocolic adipose hyperplasia in a rat 2,4,6-trinitrobenzenesulfonic acid colitis model and comparison to creeping fat in Crohn disease, Inflammatory Bowel Diseases (2026). DOI: 10.1093/ibd/izaf328