ABSTRACT
INTRODUCTION: Crohn's disease (CD) is a chronic intestinal ailment with a multifactorial etiology, whose incidence has increased during the last three decades. Recently, a role for mesenteric fat has been proposed in CD pathophysiology, since fat hypertrophy is detected nearby the affected intestinal area; however, there are few studies on this aspect. AIM: To evaluate inflammatory activity in intestinal mucosa and mesenteric fat tissue of patients with CD and controls. MATERIALS AND METHODS: Ten patients with ileocecal CD and 16 patients with non-inflammatory disease (control groups) were studied. The specimens were snap-frozen and the expression of TLR-4, F4/80, IL1-ß and IL-6 were determined by immunoblot of protein extracts. TLR4 RNA level were measured using RT-PCR. The t Test was applied (p<0.05). The local ethical committee approved the study. RESULTS: The intestinal mucosa of CD group had significantly higher protein levels of TLR-4, F4/80, IL-1ß and IL-6 than the controls. The gene expression of TLR4 was lower in the intestinal mucosa of CD compared to the control group. Regard the mesenteric fat tissue, there was no statistical difference related to TLR-4, F4/80, IL-1ß and IL-6 proteins expression. CONCLUSIONS: These findings may result from an up-regulation of macrophage activation and intracellular pathways activated by bacterial antigens, which are more important in intestinal mucosa than fat tissue in CD patients. This may represent an anomalous regulation of innate immunity and could contribute to the production of proinflammatory mediators and disease development.
ABSTRACT
Crohn's disease (CD) is a chronic intestinal disease with a multifactorial etiology. Recently, a role for mesenteric fat has been proposed in CD pathophysiology, since fat hypertrophy is detected close to the affected intestinal area; however, there are few studies regarding autophagy and the hypertrophied mesenteric tissue in CD. To evaluate autophagy-related proteins in intestinal mucosae and mesenteric fat of patients with CD and controls, patients with ileocecal CD (CD Group) and with non-inflammatory disease (FC Group) selected for surgery were studied. Expression of LC3-II was determined by immunoblotting of protein extracts. In addition, beclin-1, LC3 and Atg16-L1 RNA levels were measured using RT-PCR. The expression of LC3-II was significantly lower in the mesenteric tissue and higher in intestinal mucosae of CD when compared to controls. However, mRNA expression of autophagy-related proteins was similar when comparing the mesenteric fat groups. These findings suggest a defect in autophagy activation in the mesenteric fat tissue of CD individuals, which could be involved in the maintenance of the inflammatory process.
