Adults with Crohn's disease exhibit elevated gynoid fat and reduced android fat irrespective of disease relapse or remission

Infliximab modifies CD74-mediated lymphatic abnormalities and adipose tissue alterations in creeping fat of Crohn's disease

BACKGROUND

Lymphatic abnormalities are essential for pathophysiologic changes of creeping fat (CrF) in Crohn's disease (CD). Anti-tumor necrosis factor (TNF) therapy has been proved to alleviate CrF lesions, however, whether it achieves these by remodeling lymphatics is unknown.

METHODS

CD74 expression was detected in CrF and uninvolved mesentery of CD patients. Lymphatic functions in vitro were evaluated and lymphatic endothelium barrier were checked by transendothelial electrical resistance (TEER) and FITC-Dextran permeability. Protein level of tight junction and signaling pathways were detected by western blotting.

RESULTS

CD74 was upregulated in LECs of CrF and positively correlated with TNF-α synthesis. This was suppressed by IFX administration. In vitro, TNF-α stimulated LECs to express CD74 through NF-κB signaling pathway, and this was rescued by IFX. CD74 downregulation suppressed the abilities of LECs in proliferation, migration and tube formation. Interaction of CD74-MIF impaired LECs' barrier via reducing tight junction proteins in an ERK1/2-dependent manner, which was reversed by CD74 downregulation. Consistently, the CD patients receiving IFX therapy displayed decreased lymphangiogenesis and improved mesenteric lymphatic endothelium barrier, companied with reduced adipocyte size and adipokine levels in CrF.

CONCLUSIONS

Anti-TNF therapy could modify pathological changes in CrF by alleviating CD74-mediated lymphatic abnormalities.

Relationship between SIRI and android and gynoid fat related to obesity and cardiovascular risk: a cross-sectional study of NHANES 2017-2018

OBJECTIVE

Inflammation has a crucial role in several metabolic diseases, such as obesity. The author aimed to investigate the relationship between the system inflammation response index (SIRI) and android fat composition and distribution.

METHODS

Data for individuals aged 8-59 years, SIRI, android percent fat, and android-to-gynoid ratio from the 2017 to 2018 National Health and Nutrition Examination Survey were used. Weighted multiple linear regression and smooth curve fitting were used to test for linear and nonlinear associations. Additional subgroup analyses were performed. Threshold effect analysis was performed using a two-linear regression model.

RESULTS

Multiple linear regression showed a positive correlation between SIRI and android percent fat (β 0.92, 95% confidence interval [CI] 0.25-1.59) and between SIRI and the android-to-gynoid ratio (β 0.01, 95% CI 0.00-0.03) in 3783 Americans aged 8-59 years. The results showed that the effect of factors, other than smoking status, on the relationship between SIRI and android percent fat and android-to-gynoid ratio was not significant. There was a nonlinear relationship between SIRI and both android percent fat and android-to-gynoid ratio.

CONCLUSIONS

Elevated SIRI levels were associated with an increased android percent fat and android-to-gynoid ratio. Larger prospective studies are needed to validate the findings.

Feasibility of in vivo magnetic resonance elastography of mesenteric adipose tissue in Crohn's disease

Background

Although there is growing evidence that functional involvement and structural changes of mesenteric adipose tissue (MAT) influence the course of Crohn's disease (CD), its viscoelastic properties remain elusive. Therefore, we aimed to investigate the viscoelastic properties of MAT in CD using magnetic resonance elastography (MRE), providing reference values for CD diagnosis.

Methods

In this prospective proof-of-concept study, 31 subjects (CD: n=11; healthy controls: n=20) were consecutively enrolled in a specialized care center for inflammatory bowel diseases (tertiary/quaternary care). Inclusion criteria for the CD patients were a clinically and endoscopically established diagnosis of CD based on the clinical record, absence of other concurrent bowel diseases, scheduled surgery for the following day, and age of at least 18 years. Diagnoses were confirmed by histological analysis of the resected bowel the day after MRE. Subjects were investigated using MRE at 1.5-T with frequencies of 40-70 Hz. To retrieve shear wave speed (SWS), volumes of interest (VOIs) in MAT were drawn adjacent to CD lesions (MATCD) and on the opposite side without adjacent bowel lesions in patients (MATCD_Opp) and controls (MATCTRL). The presented study is not registered in the clinical trial platform.

Results

A statistically significant decrease in mean SWS of 7% was found for MATCD_Opp vs. MATCTRL (0.76±0.05 vs. 0.82±0.04 m/s, P=0.012), whereas there was a nonsignificant trend with an 8% increase for MATCD vs. MATCD_Opp (0.82±0.07 vs. 0.76±0.05 m/s, P=0.098) and no difference for MATCD vs. MATCTRL. Preliminary area under the receiver operating characteristic curve (AUC) analysis showed diagnostic accuracy in detecting CD to be excellent for SWS of MATCD_Opp [AUC =0.82; 95% confidence interval (CI): 0.64-0.96] but poor for SWS of MATCD (AUC =0.52; 95% CI: 0.34-0.73).

Conclusions

This study demonstrates the feasibility of MRE of MAT and presents preliminary reference values for CD patients and healthy controls. Our results motivate further studies for the biophysical characterization of MAT in inflammatory bowel disease.

Body Composition in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is associated with body composition changes, which are associated with clinical prognosis, response to therapy, and quality of life in IBD patients. Therefore, it is critical to review the body composition distribution in IBD, summarize the potential factors affecting body composition distribution, and take steps to improve the body composition distribution of IBD patients as early as possible. In the current review, we searched PubMed via keywords 'inflammatory bowel disease', or 'IBD', or 'Crohn's disease', or 'CD', or 'ulcerative colitis', or 'UC', and 'body composition'. Malnutrition and sarcopenia are common in IBD patients and are associated with the clinical course, prognosis, and need for surgery. Disease activity, reduced nutrition intake, vitamin D deficiency, and intestinal dysbiosis are factors contributing to changed body composition. Early use of biological agents to induce remission is critical to improving body composition distribution in IBD patients, supplementation of vitamin D is also important, and moderate physical activity is recommended in IBD patients with clinical remission.

Physical activity in inflammatory bowel disease: benefits, challenges and perspectives

PURPOSE OF THE REVIEW

Physical activity is gaining significative interest in the field of inflammatory bowel disease (IBD). In the light of the most recent publications, the present review aims to describe the level of physical activity in adult patients with IBD; describe the current body of evidence on the benefits of physical activity and discuss the challenges and perspectives related to physical activity in this population.

RECENT FINDINGS

Recent studies showed that IBD patients tend to be less active than healthy people. There is growing evidence of a positive impact of physical activity on mortality, quality of life, fatigue, body composition, strength and physical performance. The direct benefits of physical activity on clinical remission and disease activity have recently been observed only in Crohn's disease. Limitations to physical activity related to the disease, such as gastrointestinal and psychological symptoms, need to be considered in this population. Finally, no guidelines are available and there is no evidence regarding the effects of combined physical activity and nutritional support.

SUMMARY

Although physical activity seems beneficial and safe for IBD patients, future studies are needed to clearly define recommendations in this population.