title: Neurobehavioral alterations plus transcriptional changes of the heat shock protein 90 and hypoxia inducible factor-1α in the crucian carp exposed to copper.
abstract: The various physiological alterations caused by copper (Cu) exposure in fish have attracted great interests toward neuronal strategies against Cu toxicity. Here, neurobehavioral activities (including anxiety-like behaviors) and transcriptional levels of heat shock protein (Hsp)90 and hypoxia inducible factor-1alpha (HIF-1α) were evaluated in the crucian carp (Carassius carassius) treated with nominal sub-lethal higher (1.45mg/L) and lower (0.30mg/L) concentrations of CuCl2. Both concentrations accounted for diminished swimming speed and food intake plus a strong preference for the dark side of the light/dark apparatus together with a reduction of crossings between the two compartments with respect to controls. Contextually, Hsp90 and HIF-1α transcripts were largely down- and up-regulated, respectively, in some brain areas such as in the medial part of the dorsal telencephalon (Dm, -52%) and in the ventral part of the ventral telencephalon (Vv, +68%). When carps were transferred to CuCl2-free water, some behaviors were rescued especially for fish previously exposed to 0.30mg/L concentration. In this same condition, Hsp90 mRNA levels were recuperated (-94%) in the medial preglomerular nucleus (NPGm) with respect to exposed fish while HIF-1α mRNA was mostly down-regulated in telencephalic stations. Moreover, recovery capacities of this extraordinary resistant fish was exhibited by evident reductions (-80%) of the dark argyrophilic granules such as in the ventral telencephalon (VTel). Overall, our results point to interesting responses against Cu toxicity involving Hsp90 and HIF-1α transcripts that may constitute early indicators of environmental stressors leading to the repair of metal-induced damages in fish with notable brain plasticity properties.
authors.affiliation: Comparative Neuroanatomy Laboratory, Biology, Ecology and Earth Science Department (DiBEST), University of Calabria, 87036 Arcavacata of Rende (CS), Italy.
authors.forename: Merylin
authors.initials: M
authors.lastname: Zizza
authors.affiliation: Comparative Neuroanatomy Laboratory, Biology, Ecology and Earth Science Department (DiBEST), University of Calabria, 87036 Arcavacata of Rende (CS), Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Canonaco
authors.affiliation: Comparative Neuroanatomy Laboratory, Biology, Ecology and Earth Science Department (DiBEST), University of Calabria, 87036 Arcavacata of Rende (CS), Italy. Electronic address: rm.facciolo@unical.it.
authors.forename: Rosa Maria
authors.initials: RM
authors.lastname: Facciolo
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D002347:Carps / Q000235:genetics*; D003300:Copper / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics*; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics*; D009410:Nerve Degeneration / Q000139:chemically induced / Q000473:pathology*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D018841:HSP90 Heat-Shock Proteins; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D003300:Copper; C029892:cupric chloride
keywords: Abnormal motor behaviors; Anxiety-like behaviors; Carassius carassius; HIF-1α; Hsp90 mRNA; Recovery; mRNA