alexa Age-associated remodeling of thymopoiesis: role for gonadal hormones and catecholamines.
Molecular Biology

Molecular Biology

Journal of Cell Science & Therapy

Author(s): Leposavi G, Perisi M

Abstract Share this page

Abstract The present review summarizes recent data on age-related thymic changes termed thymic involution, and highlights the putative role of perturbances in extrathymical and, possibly, intrathymical production of gonadal steroids and catecholamines in this process. Thymic involution has been envisaged as an extremely complex process involving multifactorial mechanisms along the bone marrow-thymic axis that accounts for the major manifestations of immunosenescence. These mechanisms include basic cell aging processes (for example, cell replication and programmed cell death) and processes unique to the immune system (such as generation of the T cell receptor repertoire and control of potentially autoreactive cells). Given that the onset of age-associated thymic involution coincides with the rise in gonadal steroid levels at puberty, a causal link between these events has been suggested. It has been shown that: (1) peripubertal gonadectomy causes substantial decrease in the level of noradrenaline in adult male and female thymus and (2) catecholamines, acting via alpha- and beta-adrenoceptor, produce suppressive effects on the thymic cellularity and production of both effector and regulatory T cells. Furthermore, the possibility that gonadal steroids contribute to thymic involution is discussed in this paper. In light of recent data indicating that effects of gonadal hormone deprivation on the thymic cellularity and function are long lasting but transitory, a putative role for the intrathymic sex steroid/catecholamine production in assuring the organ involution, under conditions of their limited supply by extrathymic sources, is also considered. Copyright 2008 S. Karger AG, Basel. This article was published in Neuroimmunomodulation and referenced in Journal of Cell Science & Therapy

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version