Neurotoxicity research
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Neurotoxicity research · Jul 2014
Anti-inflammatory effects of botulinum toxin type a in a complete Freund's adjuvant-induced arthritic knee joint of hind leg on rat model.
The objective of the study is to verify histopathologically the anti-inflammatory effect of botulinum toxin type A (BoNT-A) in a Complete Freund's Adjuvant (CFA)-induced arthritic knee joint of hind leg on rat model using immunofluorescent staining of anti-ionized calcium-binding adaptor molecule 1 (Iba-1) and interleukin-1β (IL-1β) antibody. Twenty-eight experimental rats were injected with 0.1 ml of CFA solution in the knee joint of the hind leg bilaterally. Three weeks after CFA injection, the BoNT-A group (N = 14) was injected with 20 IU (0.1 ml) of BoNT-A bilaterally while the saline group (N = 14) was injected with 0.1 ml of saline in the knee joint of the hind leg bilaterally. ⋯ The binding of Iba-1 and IL-1β antibody was significantly lower in the BoNT-A group than the saline group at 1 and 2 weeks after BoNT-A injection. The number of Iba-1 and IL-1β-IR cells at 1 and 2 weeks after the injection of BoNT-A were significantly different from the corresponding number of Iba-1 and IL-1β-IR cells in the saline group. To conclude, BoNT-A had an anti-inflammatory effect in a CFA-induced arthritic rat model, indicating that BoNT-A could potentially be used to treat inflammatory joint pain.
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Neurotoxicity research · Nov 2013
Induction of neuronal mitophagy in acute spinal cord injury in rats.
Autophagy and up-regulation of autophagy-associated proteins microtubule-associated protein 1 light chain 3 (LC3) and Beclin-1 have been shown to occur in spinal cord injury (SCI). Bcl-2/E1B-19 K-interacting protein 3 (BNIP3) and Nip-like protein X (NIX, also known as BNIP3L) are mitochondrial BH3-only proteins that are implicated in mitophagy. In this study, we show that mitophagy is activated in the injured neurons, and hypoxia-inducible proteins BNIP3, NIX, and p53 are upregulated after SCI. ⋯ Hypoxia-inducible proteins BNIP3, NIX, and p53 were upregulated in spinal cord neurons in both a rat model of SCI and cultured primary spinal neurons exposed to hypoxia. BNIP3 and NIX were transcriptionally regulated mainly by hypoxia-inducible factor-1α as well as p53 in cultured spinal cord neurons. This study provides direct morphological and biochemical evidence for mitophagy in the damaged neural tissue after SCI.
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Neurotoxicity research · Aug 2013
ReviewThe role of glutamate and the immune system in organophosphate-induced CNS damage.
Organophosphate (OP) poisoning is associated with long-lasting neurological damage, which is attributed mainly to the excessive levels of glutamate caused by the intoxication. Glutamate toxicity, however, is not specific to OP poisoning, and is linked to propagation of damage in both acute and chronic neurodegenerative conditions in the central nervous system (CNS). ⋯ In this review, we will discuss the role of glutamate as an excitotoxic agent in the acute phase of OP poisoning, and the possible functions it may have as both a neuroprotectant and an immunomodulator in the sub-acute and chronic phases of OP poisoning. In addition, we will describe the novel immune-based neuroprotective strategies aimed at counteracting the long-term neurodegenerative effects of glutamate in the CNS.
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Neurotoxicity research · May 2012
Protective efficacy of coenzyme Q10 against DDVP-induced cognitive impairments and neurodegeneration in rats.
The present study was carried out to elucidate the effects of coenzyme Q(10) (CoQ(10)) against cognitive impairments induced by dichlorvos (DDVP). We have previously shown organophosphate, DDVP-induced impairments in neurobehavioral indices viz. rota rod, passive avoidance, and water maze tests. In addition to this, we have also reported that chronic DDVP exposure leads to decreased mitochondrial electron transfer activities of cytochrome oxidase along with altered mitochondrial complexes I-III activity. ⋯ Electron microscope studies of rat hippocampus mitochondria revealed that CoQ(10) administration leads to near normal physiology of mitochondria with well-defined cristae compared with DDVP-treated animals where enlarged mitochondria with distorted cristae are observed. CoQ(10) administration also attenuated neuronal damage in hippocampus as evident from histopathological studies. These results demonstrate the beneficial effects of CoQ(10) against organophosphate-induced cognitive impairments and hippocampal neuronal degeneration.
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Neurotoxicity research · Apr 2012
Behavioral, neurochemical and histological alterations promoted by bilateral intranigral rotenone administration: a new approach for an old neurotoxin.
Rotenone exposure in rodents provides an interesting model for studying mechanisms of toxin-induced dopaminergic neuronal injury. However, several aspects remain unclear regarding the effects and the accuracy of rotenone as an animal model of Parkinson's disease (PD). In order to counteract these limitations, this study characterized a precise neurotoxin-delivery strategy employing the bilateral intranigral administration protocol of rotenone as a reliable model of PD. ⋯ Furthermore, learning and memory processes were severely disrupted in different time-points, particularly at the training and test session (30 days). We now provide further evidence of a time-dependent neurodegeneration associated to cognitive impairment after the single bilateral intranigral administration of rotenone. Thus, it is proposed that the current rotenone protocol provides an improvement regarding the existing rotenone models of PD.