Intestinal barrier function is maintained with aging – a comprehensive study in healthy subjects and irritable bowel syndrome patients

Abstract

Animal studies have shown that intestinal barrier function is compromised with aging. We aimed to assess the effects of aging on intestinal barrier function in humans in vivo and ex vivo. In this crosssectional study, healthy subjects and subjects with irritable bowel syndrome (IBS) of older (65-75 years) and young adult age (18-40 years) were compared. In vivo gastrointestinal site-specific permeability was assessed by a multi-sugar test, taking into account potential confounders. Sigmoid biopsies were collected from subgroups of healthy young adults and elderly for ex vivo Ussing chamber experiments, gene transcription of barrier-related genes and staining of junctional proteins. No significant differences between healthy young adults and elderly were found for small intestinal, colonic and whole gut permeability (P ≥ 0.142). In IBS patients, gastroduodenal and colonic permeability did not differ significantly (P ≥ 0.400), but small intestinal and whole gut permeability were higher in elderly versus young adults (P ≤ 0.009), mainly driven by the IBS-diarrhea subtype. Ussing chamber experiments with or without stressor (P ≥ 0.052), and relative expression of intestinal barrier-related genes (P ≥ 0.264) showed no significant differences between healthy elderly and young adults, as confirmed by immunofluorescent stainings. Overall, the functional capacity of the intestinal barrier is maintained in elderly.Along with the rising life expectancy, the aging population is steadily increasing worldwide. In 2010, 8% of the world population was aged 65 years or older, and this proportion is expected to reach 16% by 2050, leading to substantial increases in direct and indirect health care costs 1 . The associated functional decline of several organs and tissues, including those of the gastrointestinal (GI) tract and the immune system, contributes to higher vulnerability to infections with aging and age-related co-morbidities 2,3 . With respect to GI physiology and function, a recent review by our group showed that the aging process is associated with small, subtle alterations at both the organ and cellular level 4 . Moreover, the GI mucosal immune function has been found to decline with aging 5 . Based on data of mice, rat and baboon studies it has been stated that intestinal barrier function also decreases with aging, as reflected by an increased paracellular intestinal permeability 6-9 . Intestinal permeability is an important functional feature of the intestinal epithelial barrier 10 . Increased intestinal permeability may lead to permeation of noxious luminal substances into the intestinal mucosa, inducing local and systemic immune activation, and may contribute to e.g. an increased infection risk, inflammation, and GI symptoms. So far, a few human studies have investigated the effects of aging on small intestinal or colonic barrier function. In these studies, most of

Intestinal barrier dysfunction in irritable bowel syndrome: a systematic review

“…A recent study found that elderly IBS patients have greater disruption of small intestinal barrier compared with their younger counterparts. 110 Another study, however, found no effect of adjusting for age on permeability changes in IBS-D. 50 Furthermore, the expression of several tight junction (occludin, ZO-1 and CLDN-1) and adherens junction (JAM-1 and E-cadherin) molecules was not correlated with age in IBS patients. 49 , 85 , 87 , 90 There is an established female predominance in IBS.…”

Digestive Enzyme Activity and Protein Degradation in Plasma of Heart Failure Patients

“…Increased intestinal permeability has been reported in inflammatory bowel disease, diabetes, and more recently HF, where leakage of pancreatic enzymes into the circulation is exacerbated by gut oe- dema and hypoperfusion. 40,45,49,51 Whereas the rapid appearance of trypsin (within minutes) after a high fat diet meal 26 suggests that trypsin acutely leaks out of the small intestine, under chronic HF conditions leakage out of the intestine and/or the pancreas are possible. Ultimately, to further resolve the question about the exact source of trypsin there is a need to trace its activity during food administration of isotopically labelled trypsin and its detection in serum using mass spectrometry.…”

Trifostigmanoside I, an Active Compound from Sweet Potato, Restores the Activity of MUC2 and Protects the Tight Junctions through PKCα/β to Maintain Intestinal Barrier Function

“…Tumor necrosis factor (TNF)-α is a key regulator of intestinal inflammation and is responsible for increasing the permeability of intestinal TJs. Activation of TNF-α leads to rapid activation of the NF-𝜅B/p65 signaling pathway [ 20 , 21 ]. Therefore, p65 is considered a biomarker of the activation of inflammation-related pathways affecting intestinal barrier function.…”