Polymeric Formula Has Direct Anti-Inflammatory Effects on Enterocytes in an in VitroModel of Intestinal Inflammation

Abstract

Exclusive enteral nutrition using polymeric formula (PF) is a well-established therapeutic option for active Crohn's disease; however, its mechanisms of action are unknown. We investigated the anti-inflammatory effects of PF in an in vitro model of epithelial cell inflammation. PF did not affect cell viability over a range of dilutions, but when PF was added to the culture medium the interleukin (IL)-8 response to proinflammatory stimuli was significantly reduced. This effect was due to PF acting directly on the cells as the IL-8 response was still reduced when PF was separated from the proinflammatory stimuli in a 2-compartment system. In the presence of PF, nuclear factor (NF)-kappaB nuclear migration was not inhibited; however, IkappaBalpha degradation was delayed. PF has direct anti-inflammatory effects upon immortalized colonic enterocytes. Therefore PF may, in part, modulate gut inflammation by directly reducing the inflammatory response of the intestinal epithelium.

The major pathway by which polymeric formula reduces inflammation in intestinal epithelial cells: a microarray-based analysis

“…HT-29 cells were washed with warm 19 PBS and were detached with 0.25 % trypsin/EDTA solution as described previously (de Jong et al 2007;Nahidi et al 2012). Warm FBS (500 ll/ well) was added to inhibit the trypsin reaction.…”

“…Warm FBS (500 ll/ well) was added to inhibit the trypsin reaction. Cell suspensions were then mixed with an equal volume of trypan blue solution and applied to a haemocytometer chamber for cell counting (de Jong et al 2007). Cells were examined by light microscope (Nikon, Japan) to detect any changes in morphology and to determine uptake of the dye (the trypan blue-negative cells were considered to be viable).…”

“…Prior to experiments, cells were washed twice with warm sterile 19 Dulbecco's phosphatebuffered saline (PBS; Gibco) and then treated with 100 ng/ ml of TNF-a in the presence or absence of PF (1:5 dilution) for 5 h (Boonkaewwan et al 2008;de Jong et al 2007). In each series of experiments, supernatants were collected following stimulation of the cells and stored at -80°C until required for subsequent analysis.…”

“…In addition, there are data that EEN improves the patient's nutritional status (Thomas et al 1993). Beyond the nutritional benefits, EEN has been shown to alleviate clinical symptoms and rapidly decrease disease activity in CD patients by influencing the underlying mucosal immune response and inflammatory processes (de Jong et al 2007;Fell et al 2000). Furthermore, EEN is considered safe, as it induces remission and mucosal healing with minimal side effects compared to current pharmacological therapies (Fell et al 2000).…”

Exclusive enteral nutrition and induction of remission of active Crohn’s disease in children

“…In a two-compartment model of epithelial inflammation, de Jong et al showed that PF prevented the epithelial inflammatory response to the proinflamm atory cytokine TNF-α [48]. Levels of IL-8 were substantially lower when cells were treated with PF before or after stimulation with TNF-α.…”