Dataset Information

WNT signaling suppression in the senescent human thymus.

ABSTRACT: Human thymus is completely developed in late fetal stages and its function peaks in newborns. After the first year of life, the thymus undergoes a progressive atrophy that dramatically decreases de novo T-lymphocyte maturation. Hormonal signaling and changes in the microRNA expression network are identified as underlying causes of human thymus involution. However, specific pathways involved in the age-related loss of thymic function remain unknown. In this study, we analyzed differential gene-expression profile and microRNA expression in elderly (70 years old) and young (less than 10 months old and 11 years old) human thymic samples. Our data have shown that WNT pathway deregulation through the overexpression of different inhibitors by the nonadipocytic component of the human thymus stimulates the age-related involution. These results are of particular interest because interference of WNT signaling has been demonstrated in both animal models and in vitro studies, with the three major hallmarks of thymic involution: (i) epithelial structure disruption, (ii) adipogenic process, and (iii) thymocyte development arrest. Thus, our results suggest that secreted inhibitors of the WNT pathway could be explored as a novel therapeutical target in the reversal of the age-related thymic involution.

SUBMITTER: Ferrando-Martinez S

PROVIDER: S-EPMC4351388 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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WNT signaling suppression in the senescent human thymus.

Ferrando-Martínez Sara S Ruiz-Mateos Ezequiel E Dudakov Jarrod A JA Velardi Enrico E Grillari Johannes J Kreil David P DP Muñoz-Fernandez M Ángeles MÁ van den Brink Marcel R M MR Leal Manuel M

The journals of gerontology. Series A, Biological sciences and medical sciences 20140322 3

Human thymus is completely developed in late fetal stages and its function peaks in newborns. After the first year of life, the thymus undergoes a progressive atrophy that dramatically decreases de novo T-lymphocyte maturation. Hormonal signaling and changes in the microRNA expression network are identified as underlying causes of human thymus involution. However, specific pathways involved in the age-related loss of thymic function remain unknown. In this study, we analyzed differential gene-ex ...[more]

PMID: 24657825

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Dataset Information

WNT signaling suppression in the senescent human thymus.

Publications

WNT signaling suppression in the senescent human thymus.

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