The impact of ageing on the intestinal epithelial barrier and immune system

The ageing gastrointestinal tract

“…This methodology allows new analytical approaches which will provide insights into the function of the enteric nervous system in experimental models of human disease and ageing. The intestinal epithelium is characterized by rapid turnover, and both tissue renewal and regeneration are compromised in the ageing intestinal epithelium [9]. The age-related intestinal barrier dysfunction may be associated with mucosal atrophy, and damage to epithelial tight junction structure with decreased epithelial tight junction protein, as has been observed in older (24 months old), when compared with younger (3 and 12 months old), rats [35].…”

“…In the elderly population, the response to infections is often exacerbated by malnutrition [9]. Malnutrition is a common condition in elderly residents in long-term care (85%), as well as in hospitalized (23-62%) and community dwelling elderly (15%) [10].…”

Age-associated modifications of intestinal permeability and innate immunity in human small intestine

“…However, currently our knowledge on the effects of ageing on the physical and immunological properties of the intestinal epithelial barrier is very limited. Most importantly the lack of knowledge is particularly profound in humans [5]. The gut is the primary and largest area of contact with environmental factors and antigens and contains the largest number of immune cells in the body and the intestinal barrier is integral to GI-defence in preventing or limiting exposure of the host and its immune system to luminal antigens.…”

Mechanisms of Cell Polarity–Controlled Epithelial Homeostasis and Immunity in the Intestine

“…Along the same lines, further studies are required to determine the organization and function of the endosomal system, expression, and function of cell polarity -determining proteins, and immunity-regulating cell-surface proteins (1) along the vertical (crypt-to-villus) axis (e.g., Lindfors et al 2001;Xiong et al 2016), (2) along the horizontal (from duodenum to colon) axis of the intestine (Middendorp et al 2014), and (3) as a function of age (Man et al 2014;Soenen et al 2016), and to determine how variations herein contribute to the regulation of intestinal epithelial homeostasis and immunity.…”