English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/38869
Title: Age-related changes in melatonin synthesis in rat extrapineal tissues
Authors: Sánchez-Hidalgo, M.; Alarcon de la Lastra, C.; Carrascosa-Salmoral, M. P.; Naranjo, M. C.; Gómez-Corvera, A.; Caballero, B.; Guerrero, J. M.
Keywords: Extrapineal melatonin
Issue Date: 20-Feb-2009
Publisher: Elsevier
Citation: Experimental Gerontology 44(5): 328-334 (2009)
Abstract: In the search of new therapeutic targets improving the quality of life of elderly, melatonin, “the chemical expression of darkness”, seems to play a remarkable role in aging process possibly due to its antioxidant, immunoenhancer and anti-aging properties. The present study was designed to elucidate effects of aging in melatonin extrapineal synthesis and investigate evident age-related alterations in the action mechanisms involved. The presence of the two key enzymes involved in melatonin synthesis, arylalkylamine-N-acetyltransferase (AA-NAT) and hydroxyindole-O-methyltransferase (HIOMT) was analyzed in thymus, spleen, liver, kidney and heart of 3- and 12 month-old rats using real time PCR as well as its functionality by enzymatic activity assays. In addition, extrapineal melatonin content was measured by a competitive enzyme immunoassay (ELISA). The results of this study reveal that all rat tissues studied including thymus, and for the first time, spleen, liver, kidney and heart have the necessary machinery to synthesize melatonin. Moreover, we report an age-related decline in rat extrapineal melatonin synthesis with a consequent HIOMT functionality decrease in spleen, liver and heart during physiological aging. On the contrary, NAT enzymatic activity maintains unchanged without evident alterations with advancing age. Moreover, diminished melatonin concentrations were measured in these tissues cited above during aging except in the thymus, where, surprisingly, melatonin content, NAT/HIOMT expression, and enzymatic functionality assays revealed no significant alterations with age. As a conclusion, we report evident age-related changes in melatonin synthesis in some rat peripheral organs. We suggest that thymus may develop compensatory mechanisms to counteract the loss of immune activity and consequently, the loss of this potent antioxidant, during physiological aging.
Description: 7 páginas, 5 figuras, 1 tabla.
Publisher version (URL): http://dx.doi.org/10.1016/j.exger.2009.02.002
URI: http://hdl.handle.net/10261/38869
DOI: 10.1016/j.exger.2009.02.002
ISSN: 0531-5565
References: PMID:19233254
Appears in Collections:(IBIS) Artículos
Files in This Item:
There are no files associated with this item.
Show full item record

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.