Expression, Distribution and Role of Aquaporin Water Channels in Human and Animal Stomach and Intestines

Abstract

Stomach and intestines are involved in the secretion of gastrointestinal fluids and the absorption of nutrients and fluids, which ensure normal gut functions. Aquaporin water channels (AQPs) represent a major transcellular route for water transport in the gastrointestinal tract. Until now, at least 11 AQPs (AQP1–11) have been found to be present in the stomach, small and large intestines. These AQPs are distributed in different cell types in the stomach and intestines, including gastric epithelial cells, gastric glands cells, absorptive epithelial cells (enterocytes), goblet cells and Paneth cells. AQP1 is abundantly distributed in the endothelial cells of the gastrointestinal tract. AQP3 and AQP4 are mainly distributed in the basolateral membrane of epithelial cells in the stomach and intestines. AQP7, AQP8, AQP10 and AQP11 are distributed in the apical of enterocytes in the small and large intestines. Although AQP-null mice displayed almost no phenotypes in gastrointestinal tracts, the alterations of the expression and localization of these AQPs have been shown to be associated with the pathology of gastrointestinal disorders, which suggests that AQPs play important roles serving as potential therapeutic targets. Therefore, this review provides an overview of the expression, localization and distribution of AQPs in the stomach, small and large intestine of human and animals. Furthermore, this review emphasizes the potential roles of AQPs in the physiology and pathophysiology of stomach and intestines.

Dynamic Reorganization of Chromatin Accessibility Signatures during Dedifferentiation of Secretory Precursors into Lgr5+ Intestinal Stem Cells

“…2E). Indeed, the CD69 + CD274 + population lacks Chga , Cck , Ghrl , and other abundant EE transcripts but selectively expresses known goblet-cell genes (Pelaseyed et al, 2014; Zhu et al, 2016) (Figs. 2E–F and S3D).…”

Characterization and expression profiles of aquaporins (AQPs) 1a and 3a in mud loach Misgurnus mizolepis after experimental challenges

“…Apart from serving as the site of nutrient uptake and osmoregulation, the intestine functions as a critical defense barrier to the external environment (Grosell 2011). The intestinal fluid balance in the fish as well as mammalian has been indicated to be cooperated by various factors, including hormones, intestinal contents, inflammatory factors, and feeding (Rombout et al 2011;Zhu et al 2016). Thus, the bacterial challenge may either directly or indirectly linked to unfavorable change of water balance in the intestine in the pathophysiological stress.…”

Trefoil factor family peptides enhance cell migration by increasing cellular osmotic permeability and aquaporin 3 levels

“…AQPs are a family of transmembrane transporter proteins and are subdivided into 3 groups based on their functional characteristics: 1) orthodox AQPs (AQP1, 2, 4, and 5), which are selectively permeable for water; 2) aquaglyceroporins (AQP3, 7, 9, and 10), which are permeable to glycerol, urea, and other small solutes, in addition to water; and 3) unorthodox AQPs (AQP6, 8, 11, and 12), with peculiar intracellular localization and functions (for review see Matsuzaki et al 30). We focused on AQP3 because of its localization on the membranes of gastric and intestinal cells (14) and the fact that cell AQP3 knockdown and mouse knockout models resulted in reduced migration, lamellipodia formation, and increased sensitivity to injury (13,15).…”

“…In a further series of studies, we examined whether any effects found were mediated through TFF actions on AQP levels, with particular focus on AQP3. That focus was based on the findings that AQP3 is produced in surface enterocytes of both the stomach and intestine (13) and using a variety of models, including knockdown and knockout models, has been shown to be important in maintaining gut integrity, increasing cell migration, and stimulating repair (14, 15).…”