DEFAR - Departamento de Farmácia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530

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Resultados da Pesquisa

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    Mapping of brain activity in the analgesia induced by Phα1β and morphine.
    (2022) Diniz, Danuza Montijo; Malamut, Carlos; Araújo, Marina Rios; Ferreira, Andréa Vidal; Silva, Juliana Figueira; Cordeiro, Marta do Nascimento; Borges, Marcia Helena; Silva, Marco Aurélio Romano; Gomez, Marcus Vinicius; Castro Junior, Célio José de
    Preclinical evidence suggests the potential of Phα1β, a toxin obtained from the venom of spider Phoneutria nigriventer, as a new analgesic drug. Molecular brain imaging techniques have afforded exciting opportunities to examine brain processes in clinical pain conditions. This paper aims to study the brain regions involved in the analgesic effects of Phα1β compared with Morphine, in a model of acute pain induced by formalin in Sprague Dawley rats. We used 18F-fluorodeoxyglucose as a metabolic radiotracer to perform brain imaging of rats pretreated with Phα1β or Morphine in a model of acute inflammatory pain caused by intraplantar injection of formalin. The rats’ hind paw’s formalin stimulation resulted in a brain metabolic increase at the bilateral motor cortex, visual cortex, somatosensory cortex, thalamus, and cingulate cortex.In rats treated with Phα1β, selective inhibition of unilateral motor cortex and cingulate cortex was observed. Morphine treatment leads to small and selective inhibition at the bilateral amygdala striatum and accumbens. Our results indicate that the analgesic effect of Phα1β and Morphine possesses a differential profile of central processing in the pain state.
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    Analgesic effects of Phα1β toxin : a review of mechanisms of action involving pain pathways.
    (2021) Silva, Juliana Figueira da; Binda, Nancy Scardua; Pereira, Elizete Maria Rita; Lavor, Mário Sérgio Lima de; Vieira, Luciene Bruno; Souza, Alessandra Hubner de; Rigo, Flávia Karine; Ferrer, Hèlia Tenza; Castro Junior, Célio José de; Ferreira, Juliano; Gomez, Marcus Vinicius
    Phα1β is a neurotoxin purified from spider venom that acts as a high-voltage-activated (HVA) calcium channel blocker. This spider peptide has shown a high selectivity for N-type HVA calcium channels (NVACC) and an analgesic effect in several animal models of pain. Its activity was associated with a reduction in calcium transients, glutamate release, and reactive oxygen species production from the spinal cord tissue and dorsal ganglia root (DRG) in rats and mice. It has been reported that intrathecal (i.t.) administration of Phα1β to treat chronic pain reverted opioid tolerance with a safer profile than ω-conotoxin MVIIA, a highly selective NVACC blocker. Following a recent development of recombinant Phα1β (CTK 01512-2), a new molecular target, TRPA1, the structural arrangement of disulphide bridges, and an effect on glial plasticity have been identified. CTK 01512-2 reproduced the antinociceptive effects of the native toxin not only after the intrathecal but also after the intravenous administration. Herein, we review the Phα1β antinociceptive activity in the most relevant pain models and its mechanisms of action, highlighting the impact of CTK 01512-2 synthesis and its potential for multimodal analgesia.