@conference{
author = "Prokić, Marko and Gavrilović, Branka and Krizmanić, Imre and Gavrić, Jelena and Nasia, Mohammed and Borković Mitić, Slavica and Pavlović, Slađan and Despotović, Svetlana and Radovanović, Tijana and Saičić, Zorica",
year = "2017",
abstract = "In temperate regions, low temperatures and the lack of food during the
winter lead the water frogs to hibernate in order to survive. Hibernation
represents an adaptation mechanism and is a part of frogs yearly life cycle
(Wells, 2007). Hibernation, as well as pre- (autumn) and post-hibernation
(spring) periods are characterized by different biochemical, physiological,
morphological and behavioral changes, all in order to prepare the organisms
for a significant depression in aerobic metabolic rate (autumn) and then
recovery to a normal state (spring). An important role in this response plays
the antioxidative defense system (AOS), especially in spring, when increased
metabolic rate during arousal is followed by high oxygen consumption and
reactive oxygen species (ROS) generation. Oxidative stress is also induced by
various xenobiotics in the environment and this raises the question of their
share in oxidative stress of hibernators in a yearly cycle?
To examine this we first determined concentrations and seasonal
variations of accumulated metals (As, Cd, Cr, Fe, Hg, Ni, Pb, Zn) and AOS
parameters (superoxide dismutase (SOD), catalase (CAT), glutathione
peroxidase (GSH- Px), glutathione reductase (GR), glutathione-S-transferase
(GST) and glutathione (GSH) and sulfhydryl (SH) groups concentrations) in
skin and muscle of Pelophylax ridibundus during pre- (autumn) and post- hibernation (spring) periods, and second we evaluated the possible
relationship between accumulated metals and AOS parameters.
The results showed seasonal variation of accumulated concentrations:
autumn frogs were characterized by higher concentrations of Ni, Cr and Hg,
while frogs sampled in spring had higher As and Cd. On the other hand
almost all AOS parameters were higher during the spring in comparison to
individuals from autumn (in skin SOD, CAT, GR, GST, GSH and SH groups,
while in muscle SOD, CAT, GSH-Px, GR and SH groups). The number of
significant correlations between accumulated metals and AOS parameters
were very similar in frogs from both seasons.
All results showed that oxidative stress in the post-hibernating season was
mainly caused by the organism’s recovery from hibernation, and that the
metals did not contribute significantly to this response, indicating that natural
selection affected AOS of the frogs in that way that during arousal they were
able to produce higher levels of antioxidant defenses.",
publisher = "Association of Naturalists Students of the Jagiellonian University",
journal = "Abstract Book: Conference of young evolutionary biologist; 2017 Jun 2-4; Krakow, Poland",
title = "Heavy metals, oxidative stress and their relationship in Pelophylax ridibundus frogs during pre- and posthibernation period",
pages = "45-46",
url = "https://hdl.handle.net/21.15107/rcub_ibiss_3420"
}
