Alterations in epididymal sperm maturation caused by ageing
B. P. López-Trinidad A H , R. M. Vigueras-Villaseñor B , M. Konigsberg C , A. Ávalos-Rodríguez D , A. Rodríguez-Tobón E H , E. Cortés-Barberena F , M. Arteaga-Silva G and E. Arenas-Ríos
H *
+ Author Affiliations
- Author Affiliations
A Doctorado en Biología Experimental. Universidad Autónoma Metropolitana. Unidad Iztapalapa. Ciudad de México, México.
B Laboratorio de Biología de la Reproducción, Instituto Nacional de Pediatría, Ciudad de México, México.
C Laboratorio de Bioenergética y envejecimiento Celular, Universidad Autónoma Metropolitana. Unidad Iztapalapa. Ciudad de México, México.
D Laboratorio de Bioquímica de la Reproducción, Universidad Autónoma Metropolitana. Unidad Xochimilco. Ciudad de México, México.
E Laboratorio de Ecología y Biología de Mamíferos, Universidad Autónoma Metropolitana. Unidad Iztapalapa. Ciudad de México, México.
F Laboratorio de Biología Celular y Citometría de Flujo, Universidad Autónoma Metropolitana. Unidad Iztapalapa. Ciudad de México, México.
G Laboratorio de Neuroendocrinología Reproductiva, Universidad Autónoma Metropolitana. Unidad Iztapalapa. Ciudad de México, México.
H Laboratorio de Morfofisiología y Bioquímica del Espermatozoide, Universidad Autónoma Metropolitana. Unidad Iztapalapa. Ciudad de México, México.
Reproduction, Fertility and Development 33(18) 855-864 https://doi.org/10.1071/RD21081
Published online: 30 November 2021
© 2021 The Author(s) (or their employer(s)). Published by CSIRO Publishing
Abstract
The epididymis is an organ that performs all the biochemical changes responsible for sperm maturation. During ageing, histological alterations in the epididymis and decreased protein synthesis have been found. This might affect the sperm maturation process. The aim of this study was to determine if the changes in the epididymis during ageing might cause alterations in sperm maturation. Wistar rats of 3–4 months old (young) and 18–21 months old (old) were used. The testosterone concentration was determined and the epididymides were dissected and divided in three regions: caput, corpus, and cauda. The tissues were used for histological processing and sperm extraction. Testosterone concentration decreased 34% in the old animals compared to the young ones. The distribution of mannose, sialic acid, and N-acetylglucosamine in the glycocalyx of the sperm membrane of old animals was different from that of young animals. The same occurred with phosphatidylserine externalisation and protein phosphorylation at tyrosine residues. Epididymis histology in old animals showed tubular and cellular degeneration. Our results suggest that ageing affects maturational markers, likely due to alterations in the epididymis as a result of the testosterone decrease associated with ageing.
Keywords: ageing, epididymis, externalization of phosphatidylserine, membrane carbohydrates, rats, sperm, sperm maturation, testosterone, tyrosine phosphorylation.
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