In a compelling study published in Cell on September 17, 2025, Stanford researchers have shifted the spotlight to an abnormal type of fat, colloquially termed “creeping fat,” which aggressively envelops the intestines in Crohn’s patients. Unlike benign adiposity, this pathological fat contributes directly to the formation of intestinal fibrosis, a scarring process that stiffens and narrows the bowel in what are known clinically as strictures. This insight reframes creeping fat from a mere symptom of disease to an active player exacerbating the progression of Crohn’s, offering novel molecular targets for intervention that were previously unconsidered.

Crohn’s disease, a perplexing and chronic inflammatory condition of the gastrointestinal tract, generally emerges in adolescence or early adulthood. Patients suffer from a cascade of symptoms—including relentless abdominal pain, diarrhea, malnutrition, and profound fatigue—that deeply impact quality of life. While anti-inflammatory treatments can sometimes achieve remission, a significant subset of patients inevitably progress to develop strictures, a severely fibrotic thickening that impairs intestinal function. Surgical excision remains the primary recourse for strictures; however, this approach is far from ideal, given its invasive nature and the high rate of recurrence.

The challenge in managing strictures lies not only in their physical toll but in their biological complexity. Prior investigations noted the consistent presence of creeping fat adjacent to these scarred intestinal segments, but the mechanistic links remained elusive. This new study, led by pediatric surgeon Jeong Hyun and surgeon-scientist Michael Longaker, probes these mechanisms with unprecedented rigor, combining human tissue analysis and sophisticated animal modeling. Their work reveals that creeping fat houses specialized fibroblasts that are highly responsive to mechanical stress—a factor previously underappreciated in Crohn’s pathogenesis.

Detailed genetic and molecular profiling of fibroblasts within creeping fat tissue discloses a fascinating mechanosensitivity: these cells detect and respond to mechanical strain emanating from the tense, inflamed intestine. This response includes the production of extracellular matrix components, the fundamental constituents of fibrotic scar tissue. Crucially, these activated fibroblasts concentrate at the interface where fat meets intestine, suggesting a localized, dynamic interplay that intensifies tissue stiffening. This insight overturns the conventional mucosa-centric view of Crohn’s, which has historically focused on immune-driven inflammation within the innermost bowel layers.

Equally groundbreaking is the development of an animal model that faithfully recapitulates the human Crohn’s phenotype, including hallmark creeping fat and stricture formation. In this model, mechanical tension of the intestine synergizes with chronic inflammation to activate the fibroblasts in adjacent fat, thereby fueling fibrosis. Such a paradigm foregrounds the role of biomechanical forces alongside immune dysregulation—an integrative perspective that better explains the complex progression of the disease.

The molecular pathways elucidated in this process include the highly conserved YAP/TAZ signaling cascade, known to mediate cellular responses to mechanical stimuli across diverse tissues. Longaker’s laboratory, previously engaged in exploring scar formation in skin, identified that inhibiting YAP/TAZ signaling in fat-resident fibroblasts drastically reduces the fibrotic response in the intestines of diseased mice. This discovery not only implicates a specific, druggable target but also aligns intestinal fibrosis with broader principles of mechanically induced scarring, revealing a potential therapeutic avenue previously untapped in Crohn’s management.

These insights carry profound clinical implications. Current anti-inflammatory regimens address only one facet of Crohn’s pathophysiology—immune activation—while ignoring the potent feedback loop established by creeping fat and mechanosensitive fibrosis. Patients who experience escalating fibrosis despite medication highlight this gap in treatment strategies. The identification of fat-derived fibroblasts as drivers of strictures points toward therapies that could intercept scarring processes before surgery becomes necessary, potentially transforming patient outcomes.

The emotional and physical burden borne by Crohn’s patients is immense. Jeong Hyun, who regularly performs surgeries to excise fibrotic strictures, describes the experience of his patients as one marked by unpredictability and chronic suffering. The inability to control symptom flare-ups or disease progression inflicts a dual hardship—bodily and psychological. This research not only illuminates a path forward scientifically but also holds promise for ameliorating a disease that, until now, offered limited avenues beyond invasive interventions.

Furthermore, the notion of “outside-in” signaling introduced by this study—that inflammation and mechanical forces permeate the full thickness of the bowel wall and the surrounding fat—is a significant conceptual advance. It challenges the prevailing “inside-out” dogma, which confined pathogenetic considerations to layers closest to the intestinal lumen. Recognizing the mesentery and creeping fat as bioactive sites reshapes the therapeutic landscape and necessitates a broader approach to drug development.

This finely detailed exploration also underscores the power of multidisciplinary collaboration. Contributions from institutions beyond Stanford, including Case Western Reserve University and the Icahn School of Medicine at Mt. Sinai, as well as support from a spectrum of funding agencies, illustrate the collective effort required to tackle complex diseases like Crohn’s. Such synergy between surgical insight, molecular biology, and translational research is key to accelerating progress in difficult clinical arenas.

In conclusion, the Stanford-led study reinvents our understanding of fat’s role in Crohn’s disease, transforming creeping fat from a passive marker of disease into a mechanosensitive culprit driving fibrosis. The revelation that biomechanical forces and associated signaling pathways contribute crucially to intestinal scarring underscores the urgency of developing targeted anti-fibrotic therapies. If successful, these could revolutionize care, reducing the need for repeated surgeries and profoundly improving the lives of millions affected by this relentless disease.

Subject of Research: Animals
Article Title: Creeping fat-derived mechanosensitive fibroblasts drive intestinal fibrosis in Crohn’s disease strictures
News Publication Date: 17-Sep-2025
Web References: https://profiles.stanford.edu/jeong-hyun, https://profiles.stanford.edu/michael-longaker, https://profiles.stanford.edu/khristian-bauer-rowe-ramos, https://med.stanford.edu/
References: Study published in Cell, September 17, 2025
Keywords: Crohn disease, inflammatory bowel diseases, intestinal fibrosis, creeping fat, fibroblasts, mechanosensitive signaling, YAP/TAZ pathway, intestinal strictures

Recent research conducted at the University of Delaware presents promising advancements in understanding obesity at a genetic level. The study, led by Ibra Fancher, an assistant professor of kinesiology and applied physiology, reveals critical insights into how fat tissue—known scientifically as adipose tissue—contributes to obesity and related health issues. Traditionally, adipose tissue has been viewed merely as a storage depot for excess calories; however, emerging science now recognizes this tissue as a complex endocrine organ capable of influencing metabolic health.

In an innovative study published in the journal Physiological Genomics, Fancher and his team explored the effects of diet on gene expression in adipose tissue using an animal model. Two distinct groups were established: one group was subjected to a high-fat, high-caloric diet, reflective of the typical Western dietary pattern, while the other group adhered to a standard chow diet for a period exceeding one year. This controlled environment allowed researchers to closely monitor the impacts of dietary choices on genetic expressions associated with obesity.

The findings were striking. The research uncovered over 300 genes that showed significant differences in expression levels within subcutaneous adipose tissue, which is generally regarded as a less harmful fat type. In contrast, nearly 700 genes exhibited differential expression in visceral adipose tissue. This area of fat, located around vital organs, is known to pose a greater risk for cardiovascular disease and metabolic dysfunction. Fancher elucidates the contrasting roles of these fat tissues, emphasizing that the expansion of visceral fat is both severe and problematic, contributing to the inflammatory processes that underpin many obesity-related conditions.

The core of this groundbreaking research underscores the deleterious effects that poor diet and lack of physical activity can have on specific adipose tissues. By delineating the gene expression profiles in visceral versus subcutaneous fat, Fancher’s team has illuminated viable targets for therapeutic intervention. This work suggests that targeted strategies designed to improve the function of these fat depots could offer significant health benefits and may pave the way for new treatment options for obesity.

Among the many genes analyzed in this study, four stood out as particularly significant, linked to metabolic processes, calcium handling, and inflammation. These candidates present exciting avenues for future research. Fancher posits that further investigation into these specific genes could yield new insights into enhancing adipose tissue function or provide pathways for pharmacological interventions that might mitigate the effects of obesity.

The collaborative effort leveraged the robust capabilities of advanced genomic technologies and bioinformatics available at the University of Delaware. A key player in this endeavor, Bruce Kingham, director of the Sequencing and Genotyping Center, emphasized the importance of these technical resources. Kingham noted that the integration of RNA sequencing and sophisticated data analysis tools allowed researchers to pinpoint obesity-related genetic changes with remarkable clarity. This interdisciplinary approach highlights how collaborative networks can facilitate innovative solutions to complex biomedical problems.

Malak Alradi, a doctoral student specializing in molecular biology and genetics at the University of Delaware, played an essential role in the study by categorizing genes into metabolic pathways. Alradi noted that her initial perceptions of fat as an indistinguishable entity changed significantly through this research. Witnessing the disparities in gene expression between visceral and subcutaneous fat transformed her understanding of how different types of adipose tissue respond to obesity. This insight reinforces the necessity of targeted research approaches that consider the unique biological roles and impacts of various fat types.

Statistical analyses conducted as part of the study confirmed the findings related to adipose depots, revealing important correlations between obesity, metabolism, and inflammation. Fancher expressed a sense of validation regarding the study’s discoveries, emphasizing the novelty and implications of identifying these critical obesity-related genes. This confidence in their results lays the groundwork for further exploration into the mechanisms underlying obesity at the molecular level.

Moving forward, Fancher is poised to extend this research to human adipose tissue samples. In partnership with Dr. Caitlin Halbert, who directs bariatric surgery at ChristianaCare, the team plans to assess whether the differential gene expression patterns observed in animal models translate to human physiology. This step is crucial for verifying the applicability of their findings to clinical settings and may ultimately guide strategies for individualized obesity treatments.

An important aspect of this ongoing research includes investigating potential sex differences in obesity. Fancher notes that biological variability based on sex could prove significant in determining the effective design of targeted interventions. As obesity can influence men and women differently, recognizing these variances could enhance the precision of therapeutic approaches tailored to individual patients.

Ultimately, the University of Delaware’s research contributes profoundly to the understanding of obesity, linking genetic underpinnings to dietary habits and health outcomes. The implications of this work reach far beyond academic circles; they provide a beacon of hope for developing more effective strategies to combat obesity on a public health scale. As researchers continue to unveil the intricacies of adipose tissue function, society stands to benefit from innovative, evidence-based treatments that can effectively address this complex and pervasive health issue.

As this area of inquiry advances, it not only enhances our biological understanding of obesity but also reinforces the critical importance of interdisciplinary collaborations in tackling one of the most significant health challenges of our time.

Subject of Research: Gene expression differences in adipose tissue related to obesity
Article Title: Research at the University of Delaware Uncovers Genetic Insights into Obesity
News Publication Date: 11-Nov-2024
Web References: CDC Obesity Facts
References: Physiological Genomics Article
Image Credits: Ashley Barnas Larrimore/University of Delaware
Keywords: Obesity, Adipose tissue, Gene expression, Metabolic disorders, Health research