Tissue osmolality in intestinal villi during luminal perfusion with isotonic electrolyte solutions

Jodal, Mats; Hallbäck, Dan‐Axel; Lundgren, Ove

doi:10.1111/j.1748-1716.1978.tb06049.x

Cited by 69 publications

(22 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Interestingly, while potassium is reduced in the HSD feces, the magnitude was not equivalent to the sodium elevation. However, since the normal osmolar gradient that exists from the villus tip to the villus base exceeds the osmoles of both sodium and potassium in the content, it is likely other osmolytes contribute to water absorption (32). …”

Section: Resultsmentioning

confidence: 99%

Dietary Salt Exacerbates Experimental Colitis

Tubbs

Liu

Rogers

et al. 2017

The Journal of Immunology

View full text Add to dashboard Cite

The Western Diet – characterized by high protein, sugar, fat and low fiber intake – is widely believed to contribute to the incidence and pathogenesis of inflammatory bowel diseases (IBD). However, high sodium chloride salt content, a defining feature of processed foods, has not been considered as a possible environmental factor that might drive IBD. We set out to bridge this gap. We examined murine models of colitis on either a high salt diet (HSD) or a low salt diet (LSD). We demonstrate that a HSD exacerbates inflammatory pathology in the IL-10-deficient murine model of colitis relative to mice fed a LSD. This was correlated with enhanced expression of numerous pro-inflammatory cytokines. Surprisingly, sodium accumulated in the colons of mice on a HSD, suggesting a direct effect of salt within the colon. Similar to the IL-10-deficient model, a HSD also enhanced cytokine expression during infection by Salmonella typhimurium. This occurred in the first three day of infection, suggesting that a HSD potentiates innate immune response. Indeed, in cultured dendritic cells we found that high salt media potentiates cytokine expression downstream of TLR4 activation via p38 MAPK and SGK1. A third common colitis model, administration of dextran sodium sulfate (DSS), was hopelessly confounded by the high sodium content of the DSS. Our results raise the possibility that high dietary salt is an environmental factor that drives increased inflammation in IBD.

show abstract

Section: Resultsmentioning

confidence: 99%

Dietary Salt Exacerbates Experimental Colitis

Tubbs

Liu

Rogers

et al. 2017

The Journal of Immunology

View full text Add to dashboard Cite

show abstract

“…It has been demonstrated that the villous tip contained 3-4 times as much sodium per unit weight protein as the villous base, implying that a considerable hyperosmolarity may exist at the tip portion of the villus (Jodal et al 1978). The renal medulla is routinely exposed to a greatly hyperosmotic extracellular fluid (Isabelle et al 1994), and hyperosmotic plasma is observed in chronic hypernatremia (Papadimitriou et al 1997).…”

Section: Discussionmentioning

confidence: 99%

Intracellular production of interleukin-18 in human epithelial-like cell lines is enhanced by hyperosmotic stress in vitro

Takeuchi

Okura²,

Mori³

et al. 1999

Cell and Tissue Research

View full text Add to dashboard Cite

Interleukin-18 is a novel multifunctional cytokine, which enhances natural killer cell activity and promotes the induction of cytokine production, including that of interferon-gamma by T cells and antitumor effects. Interleukin-18 is produced by cells of several different tissues (e.g., macrophages, keratinocytes, osteoblasts, and intestinal epithelium); however, it is unclear what physiological conditions or stimuli induce interleukin-18 production. To determine physiological conditions for the production of interleukin-18, we have examined the effect of mannitol-induced hyperosmotic conditions on normal human umbilical vein endothelial cells (HUVEC) and eight established human epithelial-like cell lines (Intestine 407, Caco-2, A253, HeLa, SCC25, HT1197, ACHN, A549). Hyperosmotic conditions induced interleukin-18 immunoreactivity in all the human cell lines tested, as detected by immunocytochemistry. The enhanced interleukin-18 production was also observed when mannitol was replaced with NaCl as the inducer of hyperosmotic stress. Enzyme-linked immunosorbent assays revealed that interleukin-18 concentrations in cell extracts were significantly increased by hyperosmotic conditions. Reporter gene assays also revealed that hyperosmotic conditions stimulated transcriptional activity of the interleukin-18 promoter. These results show for the first time that hyperosmotic stress is a stimulator of interleukin-18 production in epithelial-like cells.

show abstract

“…Cryoscopic techniques used in determining tissue osmolality indicate that during active absorption the lamina propria underlying the villus tips obtains a tissue osmolality of 1,000 to 2,000 mOsm [14]. Moreover, as one approaches the pericrypt lamina propria, this hyperosmolal gradient progressively diminishes [14].…”

Section: Significance Of Asymmetric Partitioning Of Paracellular Condmentioning

confidence: 98%

Partitioning of paracellular conductance along the ileal crypt-villus axis: A hypothesis based on structural analysis with detailed consideration of tight junction structure-function relationships

1984

View full text Add to dashboard Cite

Current models of intestinal transport suggest cells which absorb ions are located on the villus while secretory cells are located in the crypt and putatively have paracellular pathways which are highly conductive to Na+. One approach to assess possible variation in small intestinal paracellular conductance along the crypt-villus axis is to morphometrically analyze the structural aspects of crypt and villus tight junctions (TJs) which relate to paracellular resistance. Such detailed analysis of junctional structure in this heterogeneous epithelium would permit one to compare intestinal TJ structure-function relationships with those in a structurally simpler epithelium such as that of toad urinary bladder. This comparison would also be of considerable interest since previous similar comparisons have failed to consider in detail the geometric dissimilarity between these two epithelia. We applied light, electron microscopic, and freeze-fracture morphometric techniques to guinea pig ileal mucosa to quantitatively assess, for both crypts and villi, linear TJ density, relative surface contributions, and TJ strand counts. Mean linear TJ densities were 76.8 m/cm2 for crypt cells and 21.8 m/cm2 for villus absorptive cells. Mean TJ strand counts were 4.45 for undifferentiated crypt cell TJs and 6.03 for villus absorptive cell TJs. The villus constituted 87% and the crypt 13% of total surface. We utilized these data to predict paracellular conductance of crypts vs. villi based on equations derived from those of Claude (P. Claude, J. Membrane Biol. 39:219-232, 1978). Such analysis predicts that 73% of ileal paracellular conductance is attributable to the crypt. Furthermore, we obtained literature values for paracellular resistance in mammalian ileum and toad urinary bladder and for toad bladder TJ structure and linear density and constructed a relationship which would allow us to more accurately compare TJ structure-function correlates between these two epithelia. Such a comparison, which considers both surface amplification and TJ structure and distribution in these epithelia, shows that one would predict in vitro measured values for paracellular resistance should be approximately two orders of magnitude less in mammalian ileum than in toad urinary bladder. This predicted discrepancy (115-fold) correlates well with the observed difference (100-fold).(ABSTRACT TRUNCATED AT 400 WORDS)

show abstract

Tissue osmolality in intestinal villi during luminal perfusion with isotonic electrolyte solutions

Cited by 69 publications

References 22 publications

Dietary Salt Exacerbates Experimental Colitis

Dietary Salt Exacerbates Experimental Colitis

Intracellular production of interleukin-18 in human epithelial-like cell lines is enhanced by hyperosmotic stress in vitro

Partitioning of paracellular conductance along the ileal crypt-villus axis: A hypothesis based on structural analysis with detailed consideration of tight junction structure-function relationships

Contact Info

Product

Resources

About