Enteral versus Parenteral Nutrition: Effect on Intestinal Barrier Function

Abstract

Total parenteral nutrition (TPN), or the complete absence of enteral nutrients, is commonly used in a clinical setting. However, a major consequence of TPN administration is the development of mucosal atrophy and a loss of epithelial barrier function (EBF); and this loss may lead to an increase in clinical infections and septicemia. Our laboratory has investigated the mechanism of this TPNassociated loss of EBF using a mouse model. We have demonstrated that the mucosal lymphoid population significantly changes with TPN, and leads to a rise in IFN-γ and decline in IL-10 expression -both of which contribute to the loss of EBF. Associated with these cytokine changes is a dramatic decline in the expression of tight junction and adherens junction proteins. This article discusses the potential mechanisms responsible for these changes, and potential strategies to alleviate this loss in EBF.

The role of intestinal epithelial barrier function in the development of NEC

“…It is also important to note that lack of enteral feeds can adversely influence intestinal barrier function, in part through negative effects on IEL. 101,102 Interestingly, glutamine supplementation in parenteral nutrition may reverse these effects. 103 Premature infants are often given total parenteral nutrition (TPN) at birth.…”

“…TPN has also been shown to be associated with decreases in expression of a number of TJ components, including occludin and claudins. 101,102 A recent meta-analysis indicate that probiotics are a promising preventive therapy against NEC. 31 The potential mechanisms by which probiotics may prevent NEC have been extensively studied in experimental animal models.…”

Fasting-induced intestinal apoptosis is mediated by inducible nitric oxide synthase and interferon-γ in rat

“…However, prolonged fasting not only impairs intestinal physiological functions but also brings about intestinal barrier dysfunction, including increased epithelial permeability and impaired tight junctions, subsequently leading to bacterial translocation in patients receiving a prolonged course of total parenteral nutrition (TPN) (57). Recent studies also show that proinflammatory cytokine-induced apoptosis causes loose epithelial tight junctions and an increase in paracellular permeability, raising a possibility of apoptosis-mediated intestinal barrier dysfunction (3,44).…”

Changes in Morphology and Function in Small Intestinal Mucosa After Roux-en-Y Surgery in a Rat Model

“…The flow of luminal contents modulates intestinal mucosal structure and enterocyte function (1,17). In the absence of luminal nutrients, mucosal epithelial cells lose their function, reduce their absorptive capacity, and slow their proliferation (7,18,19). Changes in cell and tissue architecture and loss of intestinal epithelial integrity lead to an impaired histostructure, increased permeability, and failure of the intestinal mucosal barrier.…”

“…Although TPN induces intestinal atrophy (3), it also has profound effects on intraepithelial cytokine signaling (4) and mucosal immune defense (5,6) that may be independent of the mucosal atrophy itself. TPN also promotes ion transfer and permeability across the intestine in experimental animals (7,8) that may change the pharmacokinetics or effects of drugs being tested for use in patients with mucosal intestinal pathology.…”