Estrogen receptors modulate ectonucleotidases activity in hippocampal synaptosomes of male rats
NEUROSCIENCE LETTERS
Authors: Mitrovic, Natasa; Dragic, Milorad; Zaric, Marina; Drakulic, Dunja; Nedeljkovic, Nadezda; Grkovic, Ivana
Abstract
Extracellular adenine nucleotides and nucleosides, such as adenosine-5'-triphosphate (ATP) and adenosine, are among least investigated signaling factors that participate in 17 beta-estradiol (E2)-mediated synaptic rearrangements in rodent hippocampus. Their levels in the extrasynaptic space are tightly controlled by ecto-nucleoside triphosphate diphosphohydrolases1-3 (NTPDase1-3)/ecto-5'-nucleotidase (eN) enzyme chain. Therefore, the aim of the present study was to get closer insight in the E2-induced decrease in NTPDase and eN activity in the hippocampal synaptic compartment of male rats and to identify estradiol receptors (ERs i.e. ER alpha, ER beta or GPER1) responsible for the observed effects of E2. In this study we show indiscriminate participation of estradiol receptor alpha (ER alpha), -beta (ER beta) and G- protein coupled estrogen receptor 1 (GPER1) in the mediation of E2 actions in hippocampal synaptosomes of male rats. Synaptic NTPDase1-3 activities are modulated only through activation of ER beta, while activation of ER alpha, -beta and/or non-classical GPER1 decreases synaptic eN activity. Since both ATP and adenosine function as neuromodulators in the hippocampal networks, influencing its function, profound knowledge of mechanisms by which ectonucleotidases are regulated/modulated is of great importance.
An acute exposure to glyphosate-based herbicide alters aromatase levels in testis and sperm nuclear quality
ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY
Authors: Cassault-Meyer, Estelle; Gress, Steeve; Seralini, Gilles-Eric; Galeraud-Denis, Isabelle
Abstract
Roundup is the major pesticide used in agriculture worldwide; it is a glyphosate-based herbicide. Its molecular effects are studied following an acute exposure (0.5%) of fifteen 60-day-old male rats during an 8-day period. Endocrine (aromatase, estrogen and androgen receptors, Gper1 in testicular and sperm mRNAs) and testicular functions (organ weights, sperm parameters and expression of the blood-testis barrier markers) were monitored at days 68, 87, and 122 after treatment, spermiogenesis and spermatogenesis. The major disruption is an increase of aromatase mRNA levels at least by 50% in treated rats at all times, as well as the aromatase protein. We have also shown a similar increase of Gper1 expression at day 122 and a light modification of BTB markers. A rise of abnormal sperm morphology and a decrease of the expression of protamine 1 and histone 1 testicular in epididymal sperm are observed despite a normal sperm concentration and motility. (C) 2014 Elsevier B.V. All rights reserved.