Navegando por Autor "Loureiro, Samanta Oliveira"
Agora exibindo 1 - 3 de 3
Resultados por página
Opções de Ordenação
Item Antidepressant-like effects of chronic guanosine in the olfactory bulbectomy mouse model.(2021) Almeida, Roberto Farina de; Souza, Diogo Onofre; Nonose, Yasmine; Ganzella, Marcelo; Loureiro, Samanta Oliveira; Rocha, Andréia; Machado, Daniele Guilhermano; Bellaver, Bruna; Fontella, Fernanda Urruth; Leffa, Douglas Teixeira; Pettenuzzo, Letícia Ferreira; Venturin, Gianina Teribele; Greggio, Samuel; Costa, Jaderson Costa da; Zimmer, Eduardo Rigon; Elisabetsky, ElaineMajor depressive disorder (MDD) leads to pervasive changes in the health of afflicted patients. Despite advances in the understanding of MDD and its treatment, profound innovation is needed to develop fast-onset antidepressants with higher effectiveness. When acutely administered, the endogenous nucleoside guanosine (GUO) shows fast- onset antidepressant-like effects in several mouse models, including the olfactory bulbectomy (OBX) rodent model. OBX is advocated to possess translational value and be suitable to assess the time course of depressive-like behavior in rodents. This study aimed at investigating the long-term behavioral and neurochemical effects of GUO in a mouse model of depression induced by bilateral bulbectomy (OBX). Mice were submitted to OBX and, after 14 days of recovery, received daily (ip) administration of 7.5 mg/kg GUO or 40 mg/kg imipramine (IMI) for 45 days. GUO and IMI reversed the OBX-induced hyperlocomotion and recognition memory impairment, hippocampal BDNF increase, and redox imbalance (ROS, NO, and GSH levels). GUO also mitigated the OBX-induced hippocampal neuroinflammation (IL-1, IL-6, TNF-α, INF-γ, and IL-10). Brain microPET imaging ([18F]FDG) shows that GUO also prevented the OBX-induced increase in hippocampal FDG metabolism. These results provide additional evidence for GUO antidepressant-like effects, associated with beneficial neurochemical outcomes relevant to counteract depression.Item Effects of intranasal guanosine administration on brain function in a rat model of ischemic stroke.(2021) Müller, Gabriel Cardozo; Loureiro, Samanta Oliveira; Pettenuzzo, Letícia Ferreira; Almeida, Roberto Farina de; Ynumaru, Evandro Yukio; Guazzelli, Pedro Arend; Meyer, Fabíola Schons; Pasquetti, Mayara Vendramin; Castro, Marcelo Ganzela Martins de; Calcagnotto, Maria Elisa; Souza, Diogo OnofreIschemic stroke is a major cause of morbidity and mortality worldwide and only few affected patients are able to receive treatment, especially in developing countries. Detailed pathophysiology of brain ischemia has been extensively studied in order to discover new treatments with a broad therapeutic window and that are accessible to patients worldwide. The nucleoside guanosine (Guo) has been shown to have neuroprotective effects in animal models of brain diseases, including ischemic stroke. In a rat model of focal permanent ischemia, systemic administration of Guo was effective only when administered immediately after stroke induction. In contrast, intranasal administration of Guo (In-Guo) was effective even when the first administration was 3 h after stroke induction. In order to validate the neuroprotective effect in this larger time window and to investigate In-Guo neuroprotection under global brain dysfunction induced by ischemia, we used the model of thermocoagulation of pial vessels in Wistar rats. In our study, we have found that In-Guo administered 3 h after stroke was capable of preventing ischemia-induced dysfunction, such as bilateral suppression and synchronicity of brain oscillations and ipsilateral cell death signaling, and increased permeability of the blood-brain barrier. In addition, In-Guo had a long-lasting effect on preventing ischemia-induced motor impairment. Our data reinforce In-Guo adminis- tration as a potential new treatment for brain ischemia with a more suitable therapeutic window.Item Low-cost apparatus for cigarette smoke exposure in rats.(2022) Müller, Gabriel Cardozo; Loureiro, Samanta Oliveira; Pettenuzzo, Letícia Ferreira; Almeida, Roberto Farina de; Ynumaru, Evandro Yukio; Guazzelli, Pedro Arend; Meyer, Fabíola Schons; Pasquetti, Mayara Vendramin; Castro, Marcelo Ganzela Martins de; Calcagnotto, Maria Elisa; Souza, Diogo OnofreIschemic stroke is a major cause of morbidity and mortality worldwide and only few affected patients are able to receive treatment, especially in developing countries. Detailed pathophysiology of brain ischemia has been extensively studied in order to discover new treatments with a broad therapeutic window and that are accessible to patients worldwide. The nucleoside guanosine (Guo) has been shown to have neuroprotective effects in animal models of brain diseases, including ischemic stroke. In a rat model of focal permanent ischemia, systemic administration of Guo was effective only when administered immediately after stroke induction. In contrast, intranasal administration of Guo (In-Guo) was effective even when the first administration was 3 h after stroke induction. In order to validate the neuroprotective effect in this larger time window and to investigate In-Guo neuroprotection under global brain dysfunction induced by ischemia, we used the model of thermocoagulation of pial vessels in Wistar rats. In our study, we have found that In-Guo administered 3 h after stroke was capable of preventing ischemia-induced dysfunction, such as bilateral suppression and synchronicity of brain oscillations and ipsilateral cell death signaling, and increased permeability of the blood-brain barrier. In addition, In-Guo had a long-lasting effect on preventing ischemia-induced motor impairment. Our data reinforce In-Guo adminis- tration as a potential new treatment for brain ischemia with a more suitable therapeutic window.