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Altenhofen, S.

Publications and source records attributed to Altenhofen, S..

2 recordsLinked to original sources

3-Nitropropionic acid induces histological and behavioral alterations in adult zebrafish: role of antioxidants on behavioral dysfunction

Huntingtons disease (HD) is a neurodegenerative disease marked by progressive motor and non-motor symptoms such as neuropsychiatric disruption and cognitive dysfunction. It has been reported that some pathogenic mechanisms resulting in neuronal cell death in this disease involve neurodegeneration and oxidative stress. 3-Nitropropionic acid (3-NPA), a natural toxin that promotes the irreversible suppression of mitochondrial complex II, has been used to understand the HD pathogenesis. This neurotoxin mimics the biochemical, central neurodegeneration, peripheral and behavioral phenotype alterations observed in HD. Here we investigated 3-NPA (60 mg/kg) effects on histological and oxidative stress parameters on brain and muscular tissues. We also evaluated the effects of three antioxidant compounds on 3-NPA-induced behavioral phenotypes in adult zebrafish. For the evaluation of the antioxidant effects, adult zebrafish were submitted to a single acute intraperitoneal injection of vitamin C, creatine, or melatonin following 3-NPA chronic administration (60 mg/kg). 3-NPA treatment caused neurodegeneration, but did not alter the muscular tissue. 3-NPA neither change thiobarbituric acid reactive substances (TBARS) nor nonprotein thiol levels. Vitamin C and creatine treatments recovered the hypolocomotion induced by 3-NPA. Also, vitamin C and melatonin treatments improved the memory dysfunction caused by 3-NPA. Altogether, our findings showed that the 3-NPA induces neurodegeneration in adult zebrafish, and the vitamin C, creatine, and melatonin are beneficial in managing HD-like behavioral phenotypes. Thus, these antioxidants could be thought as complementary pharmacotherapies for the treatment of late-stage HD symptoms.

pharmacology and toxicology↗

Acute administration of a dopamine D2/D3 receptor agonist alters behavioral and neural parameters in adult zebrafish

The dopaminergic neurotransmitter system is involved in numerous brain functions and behavioral processes. Alterations in this neurotransmitter system are associated with the pathogenesis of several human neurological disorders. Pharmacological agents that interact with the dopaminergic system allow the investigation of dopamine-mediated cellular and molecular responses and may elucidate the biological bases of such disorders. The zebrafish, a translationally relevant biomedical research organism, has been successfully employed in prior psychopharmacology studies. Here, we evaluate the effects of quinpirole (a dopamine D2/D3 receptor agonist) in adult zebrafish on behavioral parameters and neurotransmitter levels. Adult zebrafish received intraperitoneal injections of 0.5, 1.0, or 2.0 mg/kg of quinpirole or saline (control group) twice with an inter-injection interval of 48h. All tests were performed 24h after the second injection. After acute quinpirole administration, zebrafish exhibited decreased locomotor activity, increased anxiety-like behaviors and memory impairment compared to control. However, the quinpirole administration did not affect social and aggressive behavior. Quinpirole-treated fish exhibited altered swimming patterns: fish showed stereotypic swimming characterized by repetitive behavior, swimming from corner to corner at the bottom of the tank preceded and followed by episodes of immobility. Moreover, analysis of neurotransmitter levels in the brain demonstrated a significant increase in glutamate and a decrease in serotonin, while no alterations were observed in dopamine. These findings demonstrate that dopaminergic signaling altered by quinpirole administration results in significant changes in behavior and neurotransmitter levels in the central nervous system of zebrafish. Thus, we conclude that the use of quinpirole administration in adult zebrafish may be an appropriate tool for the analysis of mechanisms underlying neurological disorders related to the dopaminergic system.

neuroscience↗