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1.
PLoS One ; 18(11): e0294280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37948406

RESUMO

Chemotherapy-induced memory loss ("chemobrain") can occur following treatment with the widely used chemotherapeutic agent doxorubicin (DOX). However, the mechanisms through which DOX induces cognitive dysfunction are not clear, and there are no commercially available therapies for its treatment or prevention. Therefore, the aim of this study was to determine the therapeutic potential of phenyl-2-aminoethyl selenide (PAESe), an antioxidant drug previously demonstrated to reduce cardiotoxicity associated with DOX treatment, against DOX-induced chemobrain. Four groups of male athymic NCr nude (nu/nu) mice received five weekly tail-vein injections of saline (Control group), 5 mg/kg of DOX (DOX group), 10 mg/kg PAESe (PAESe group), or 5 mg/kg DOX and 10 mg/kg PAESe (DOX+PAESe group). Spatial memory was evaluated using Y-maze and novel object location tasks, while synaptic plasticity was assessed through the measurement of field excitatory postsynaptic potentials from the Schaffer collateral circuit. Western blot analyses were performed to assess hippocampal protein and phosphorylation levels. In this model, DOX impaired synaptic plasticity and memory, and increased phosphorylation of protein kinase B (Akt) and extracellular-regulated kinase (ERK). Co-administration of PAESe reduced Akt and ERK phosphorylation and ameliorated the synaptic and memory deficits associated with DOX treatment.


Assuntos
Disfunção Cognitiva , Potenciação de Longa Duração , Camundongos , Animais , Masculino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Doxorrubicina/farmacologia , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Hipocampo/metabolismo , Cognição
2.
Neurosci Res ; 184: 9-18, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35842011

RESUMO

Altered inhibition/excitation (I/E) balance contributes to various brain disorders. Dysfunctional GABAergic interneurons enhance or reduce inhibition, resulting in I/E imbalances. Differences in short-term plasticity between excitation and inhibition cause frequency-dependence of the I/E ratio, which can be altered by GABAergic dysfunction. However, it is unknown whether I/E imbalances can be rescued pharmacologically using a single dose when the imbalance magnitude is frequency-dependent. Loss of PGC-1α (peroxisome proliferator activated receptor γ coactivator 1α) causes transcriptional dysregulation in hippocampal GABAergic interneurons. PGC-1α-/- slices have enhanced baseline inhibition onto CA1 pyramidal cells, causing increased I/E ratio and impaired circuit function. High frequency stimulation reduces the I/E ratio and recovers circuit function in PGC-1α-/- slices. Here we tested if using a low dose of bicuculline that can restore baseline I/E ratio can also rescue the frequency-dependent I/E imbalances in these mice. Remarkably, bicuculline did not reduce the I/E ratio below that of wild type during high frequency stimulation. Interestingly, bicuculline enhanced the paired-pulse ratio (PPR) of disynaptic inhibition without changing the monosynaptic inhibition PPR, suggesting that bicuculline modifies interneuron recruitment and not GABA release. Bicuculline improved CA1 output in PGC-1α-/- slices, enhancing EPSP-spike coupling to wild type levels at high and low frequencies. Our results show that it is possible to rescue frequency-dependent I/E imbalances in an animal model of transcriptional dysregulation with a single treatment.


Assuntos
Hipocampo , PPAR gama , Animais , Bicuculina/farmacologia , Hipocampo/fisiologia , Interneurônios/fisiologia , Camundongos , Camundongos Knockout , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/deficiência , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética
3.
Neurotoxicology ; 86: 172-179, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34391795

RESUMO

The aim of this review is to highlight our knowledge of the various drugs of abuse that can prove potential teratogens affecting the brain and cognitive development in an individual exposed to maternal consumption of such agents. Among several drugs of abuse in women, we specifically highlighted the commonly used alcohol, nicotine, opioids, cannabis, cocaine and marijuana. These drugs can affect the fetal development and slow the cognitive maturation apart from physical disabilities. However, no known therapy exists to counter the toxic potential of these drugs. Several researchers used animal models of drug abuse to understand the underlying mechanisms affecting brain development and the relevant neurotransmitter system. Identifying such targets can potentially help in drug discovery research. We reported in depth analysis of such mechanisms and discussed the potential targets for drug development research.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Neurotransmissores/metabolismo , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Teratogênicos/toxicidade , Animais , Encéfalo/embriologia , Cognição/efeitos dos fármacos , Cognição/fisiologia , Feminino , Humanos , Neurotransmissores/antagonistas & inibidores , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Transtornos Relacionados ao Uso de Substâncias/complicações
4.
Heliyon ; 7(7): e07456, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34296005

RESUMO

Doxorubicin (Dox) is a chemotherapeutic agent used widely to treat a variety of malignant cancers. However, Dox chemotherapy is associated with several adverse effects, including "chemobrain," the observation that cancer patients exhibit through learning and memory difficulties extending even beyond treatment. This study investigated the effect of Dox treatment on learning and memory as well as hippocampal synaptic plasticity. Dox-treated mice (5 mg/kg weekly x 5) demonstrated impaired performance in the Y-maze spatial memory task and a significant reduction in hippocampal long-term potentiation. The deficit in synaptic plasticity was mirrored by deficits in the functionality of synaptic `α-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) channels, including reduced probability of opening, decreased dwell open time, and increased closed times. Furthermore, a reduction in the AMPAR subunit GluA1 level, its downstream signaling molecule Ca2+/calmodulin-dependent protein kinase (CaMKII), and brain-derived neurotrophic factor (BDNF) were observed. This was also accompanied by an increase in extracellular signal regulated kinase (ERK) and protein kinase B (AKT) activation. Together these data suggest that Dox-induced cognitive impairments are at least partially due to alterations in the expression and functionality of the glutamatergic AMPAR system.

5.
Heliyon ; 6(1): e03045, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31938742

RESUMO

AIMS: This study investigated the neurotoxic effects of prenatal alcohol and nicotine exposure in the cortex and hippocampus of rodents. MAIN METHODS: Behavioral alterations, electrophysiological changes, and biochemical markers associated with cholinergic neurotransmission, neural oxidative stress, mitochondrial function, and apoptosis were evaluated. KEY FINDINGS: Prenatal alcohol exposure induced the generation of ROS, nitrite and lipid peroxide, decreased mitochondrial Complex-I and IV activities, increased Caspase-1 and 3 activities, had no effect on cholinergic neurotransmission, increased expression of PSD-95, decreased LTP and decreased performance on spatial memory tasks. However, nicotine exposure, in addition to alcohol exposure, was found to mitigate the negative effects of alcohol alone on ROS generation and spatial memory task performances. Furthermore, we also studied the role of ILK in prenatal alcohol and nicotine exposure. SIGNIFICANCE: Prenatal Smoking and/or drinking is a major health concern around the world. Thus, our current study may lead to better insights into the molecular mechanisms of fetal alcohol and nicotine exposure on the developing offspring.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31824431

RESUMO

Adiponectin is an adipokine that has recently been under investigation for potential neuroprotective effects in various brain disorders including Alzheimer's disease, stroke, and depression. Adiponectin receptors (AdipoR1 and AdipoR2) are found throughout various brain regions, including the hippocampus. However, the role of these receptors in synaptic and cognitive function is not clear. Therefore, the goal of the current study was to evaluate synaptic and cognitive function in the absence of adiponectin. The current study utilized 12-month-old adiponectin knockout (APN-KO) mice and age-matched controls to study cognitive and hippocampal synaptic alterations. We determined that AdipoR1 and AdipoR2 are present in the synaptosome, with AdipoR2 displaying increased presynaptic vs. postsynaptic localization, whereas AdipoR1 was enriched in both the presynaptic and postsynaptic fractions. APN-KO mice displayed cognitive deficits in the novel object recognition (NOR) and Y-maze tests. This was mirrored by deficits in long-term potentiation (LTP) of the hippocampal Schaefer collateral pathway in APN-KO mice. APN-KO mice also displayed a reduction in basal synaptic transmission and an increase in presynaptic release probability. Deficits in LTP were rescued through hippocampal slice incubation with the adiponectin receptor agonist, AdipoRon, indicating that acute alterations in adiponectin receptor signaling influence synaptic function. Along with the deficits in LTP, altered levels of key presynaptic and postsynaptic proteins involved in glutamatergic neurotransmission were observed in APN-KO mice. Taken together, these results indicate that adiponectin is an important regulator of cognition and synaptic function in the hippocampus. Future studies should examine the role of specific adiponectin receptors in synaptic processes.

7.
Complement Ther Med ; 47: 102206, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31780035

RESUMO

Morinda citrifolia (Noni) is a popular traditional medicinal plant consumed in various forms in several countries around the world as a complementary and alternative treatment due to its established health benefits. Noni is rich in bioactive substances and has significantly exhibited pro-oxidant and immunomodulatory effects. In this review, we highlight the pharmacological basis related to the phytochemicals and polysaccharides present in Noni and its potential therapeutic effects. We screened electronic databases such as PubMed, Google Scholar, Scopus for scientific literature. Our results indicate that Noni is beneficial for various diseases with its crude extracts showing therapeutic benefit for a wide range of pathological diseases. We believe that further pharmacological and toxicological studies in addition to well-designed controlled clinical trials can validate Noni to be an effective and novel natural product for prophylactic and therapeutic use of several diseases.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Sistema Imunitário/efeitos dos fármacos , Morinda/química , Extratos Vegetais/imunologia , Extratos Vegetais/uso terapêutico , Humanos , Polinésia
8.
Toxicol Mech Methods ; 29(6): 457-466, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31010378

RESUMO

Cognitive deficits are commonly reported by patients following treatment with chemotherapeutic agents. Anthracycline-containing chemotherapy regimens are associated with cognitive impairment and reductions in neuronal connectivity in cancer survivors, and doxorubicin (Dox) is a commonly used anthracycline. Although it has been reported that Dox distribution to the central nervous system (CNS) is limited, considerable Dox concentrations are observed in the brain with co-administration of certain medications. Additionally, pro-inflammatory cytokines, which are overproduced in cancer or in response to chemotherapy, can reduce the integrity of the blood-brain barrier (BBB). Therefore, the aim of this study was to evaluate the acute neurotoxic effects of Dox on hippocampal neurons. In this study, we utilized a hippocampal cell line (H19-7/IGF-IR) along with rodent hippocampal slices to evaluate the acute neurotoxic effects of Dox. Hippocampal slices were used to measure long-term potentiation (LTP), and expression of proteins was determined by immunoblotting. Cellular assays for mitochondrial complex activity and lipid peroxidation were also utilized. We observed reduction in LTP in hippocampal slices with Dox. In addition, lipid peroxidation was increased as measured by thiobarbituric acid reactive substances content indicating oxidative stress. Caspase-3 expression was increased indicating an increased propensity for cell death. Finally, the phosphorylation of signaling molecules which modulate LTP including extracellular signal-regulated kinase 1/2 (ERK1/2), p38 mitogen-activated protein kinase, and Akt were increased. This data indicates that acute Dox exposure dose-dependently impairs synaptic processes associated with hippocampal neurotransmission, induces apoptosis, and increases lipid peroxidation leading to neurotoxicity.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Doxorrubicina/toxicidade , Hipocampo/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Técnicas de Cultura de Células , Linhagem Celular , Relação Dose-Resposta a Droga , Complexo I de Transporte de Elétrons/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Neurônios/metabolismo , Neurônios/patologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Ratos , Ratos Sprague-Dawley
9.
Life Sci ; 199: 34-40, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29474811

RESUMO

The 2010 Deepwater Horizon (DWH) oil spill is the largest marine oil spill in US history. In the aftermath of the spill, the response efforts used a chemical dispersant, Corexit, to disperse the oil spill. The health impacts of crude oil and Corexit mixture to humans, mammals, fishes, and birds are mostly unknown. The purpose of this study is to investigate the in vivo effects of DWH oil, Corexit, and oil-Corexit mixture on the general behavior, hematological markers, and liver and kidney functions of rodents. C57 Bl6 mice were treated with DWH oil (80 mg/kg) and/or Corexit (95 mg/kg), and several hematological markers, lipid profile, liver and kidney functions were monitored. The results show that both DWH oil and Corexit altered the white blood cells and platelet counts. Moreover, they also impacted the lipid profile and induced toxic effects on the liver and kidney functions. The impacts were more pronounced when the mice were treated with a mixture of DWH-oil and Corexit. This study provides preliminary data to elucidate the potential toxicological effects of DWH oil, Corexit, and their mixtures on mammalian health. Residues from the DWH spill continue to remain trapped along various Gulf Coast beaches and therefore further studies are needed to fully understand their long-term impacts on coastal ecosystems.


Assuntos
Asseio Animal/efeitos dos fármacos , Rim/efeitos dos fármacos , Lipídeos/toxicidade , Fígado/efeitos dos fármacos , Poluição por Petróleo/efeitos adversos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Asseio Animal/fisiologia , Rim/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Roedores
10.
Toxicol Mech Methods ; 28(3): 177-186, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28874085

RESUMO

Benzylpiperazine has been designated as Schedule I substance under the Controlled Substances Act by Drug Enforcement Administration. Benzylpiperazine is a piperazine derivative, elevates both dopamine and serotonin extracellular levels producing stimulatory and hallucinogenic effects, respectively, similar to methylenedioxymethamphetamine (MDMA). However, the comparative neurotoxic effects of Piperazine derivatives (benzylpiperazine and benzoylpiperazine) have not been elucidated. Here, piperazine derivatives (benzylpiperazine and benzoylpiperazine) were synthesized in our lab and the mechanisms of cellular-based neurotoxicity were elucidated in a dopaminergic human neuroblastoma cell line (SH-SY5Y). We evaluated the in vitro effects of benzylpiperazine and benzoylpiperazine on the generation of reactive oxygen species, lipid peroxidation, mitochondrial complex-I activity, catalase activity, superoxide dismutase activity, glutathione content, Bax, caspase-3, Bcl-2 and tyrosine hydroxylase expression. Benzylpiperazine and benzoylpiperazine induced oxidative stress, inhibited mitochondrial functions and stimulated apoptosis. This study provides a germinal assessment of the neurotoxic mechanisms induced by piperazine derivatives that lead to neuronal cell death.


Assuntos
Apoptose/efeitos dos fármacos , Agonistas de Dopamina/toxicidade , Neurônios Dopaminérgicos/efeitos dos fármacos , Alucinógenos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Piperazinas/toxicidade , Proteínas Reguladoras de Apoptose/agonistas , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Drogas Desenhadas/química , Drogas Desenhadas/toxicidade , Agonistas de Dopamina/química , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Complexo I de Transporte de Elétrons/metabolismo , Alucinógenos/química , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Estrutura Molecular , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Concentração Osmolar , Piperazinas/química , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo
11.
Life Sci ; 194: 177-184, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29225110

RESUMO

The adverse effects of prenatal nicotine and alcohol exposure on human reproductive outcomes are a major scientific and public health concern. In the United States, substantial percentage of women (20-25%) of childbearing age currently smoke cigarettes and consume alcohol, and only a small percentage of these individuals quit after learning of their pregnancy. However, there are very few scientific reports on the effect of nicotine in prenatal alcohol exposure on the cerebellum of the offspring. Therefore, this study was conducted to investigate the cerebellar neurotoxic effects of nicotine in a rodent model of Fetal Alcohol Spectrum Disorder (FASD). In this study, we evaluated the behavioral changes, biochemical markers of oxidative stress and apoptosis, mitochondrial functions and the molecular mechanisms associated with nicotine in prenatal alcohol exposure on the cerebellum. Prenatal nicotine and alcohol exposure induced oxidative stress, did not affect the mitochondrial functions, increased the monoamine oxidase activity, increased caspase expression and decreased ILK, PSD-95 and GLUR1 expression without affecting the GSK-3ß. Thus, our current study of prenatal alcohol and nicotine exposure on cerebellar neurotoxicity may lead to new scientific perceptions and novel and suitable therapeutic actions in the future.


Assuntos
Cerebelo/efeitos dos fármacos , Cerebelo/embriologia , Transtornos do Espectro Alcoólico Fetal/patologia , Neurotoxinas/toxicidade , Nicotina/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Animais , Cerebelo/metabolismo , Cerebelo/patologia , Feminino , Transtornos do Espectro Alcoólico Fetal/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos , Ratos Sprague-Dawley
12.
Neurobiol Learn Mem ; 139: 98-108, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28034784

RESUMO

Retrieval of a memory appears to render it unstable until the memory is once again re-stabilized or reconsolidated. Although the occurrence and consequences of reconsolidation have received much attention in recent years, the specific mechanisms that underlie the process of reconsolidation have not been fully described. Here, we present the first electrophysiological model of the synaptic plasticity changes underlying the different stages of reconsolidation of a conditioned fear memory. In this model, retrieval of a fear memory results in immediate but transient alterations in synaptic plasticity, mediated by modified expression of the glutamate receptor subunits GluA1 and GluA2 in the hippocampus of rodents. Retrieval of a memory results in an immediate impairment in LTP, which is enhanced 6h following memory retrieval. Conversely, memory retrieval results in an immediate enhancement of LTD, which decreases with time. These changes in plasticity are accompanied by decreased expression of GluA2 receptor subunits. Recovery of LTP and LTD correlates with progressive overexpression of GluA2 receptor subunits. The contribution of the GluA2 receptor was confirmed by interfering with receptor expression at the postsynaptic sites. Blocking GluA2 endocytosis restored LTP and attenuated LTD during the initial portion of the reconsolidation period. These findings suggest that altered GluA2 receptor expression is one of the mechanisms that controls different forms of synaptic plasticity during reconsolidation.


Assuntos
Cerebelo/metabolismo , Condicionamento Clássico/fisiologia , Medo/fisiologia , Hipocampo/metabolismo , Consolidação da Memória/fisiologia , Plasticidade Neuronal/fisiologia , Receptores de AMPA/metabolismo , Animais , Peptídeos Penetradores de Células/farmacologia , Cerebelo/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Medo/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Masculino , Consolidação da Memória/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/genética , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
13.
Life Sci ; 155: 161-6, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27155395

RESUMO

AIMS: The Deepwater Horizon oil spill (also known as the BP spill) is one of the largest oil spills in the U.S. HISTORY: To manage the spill, BP used an oil spill dispersant (Corexit 9500A) to disperse the oil. However, a portion of undispersed oil eventually got emulsified and interacted with near shore sediments along the Alabama shoreline and sank to the bottom forming tarmats, also known as submerged residual oil mats (SRMs). Natural shoreline transport processes have often broken these tarmats to form smaller oil fragments, known as surface residual oil balls (SRBs) or tarballs. The long-term human and the ecological health impacts of various toxic chemicals trapped in tarmat deposits are currently unknown. The purpose of this study is to investigate the in vitro cytotoxic effects of the chemicals trapped in tarmat fragments using hippocampal (neuron), kidney (nephron) and epithelial cells. MAIN METHODS: Water accommodated fraction (WAF) of tarmat fragments was used in this study. Cytotoxicity was elucidated by the MTT assay and cellular morphology assessment. Markers of oxidative stress and apoptosis were assessed to study the toxicity effects. Statistical analysis was performed using Sigma-stat. KEY FINDINGS: Tarmat WAF induced dose-dependent cellular toxicity. Chemicals trapped in tarmat WAF inhibited cell viability in the hippocampal (H19), kidney (HEK-293) and epithelial (MCF-10A) cells. Tarmat WAF also generated reactive oxygen species and increased activity of superoxide dismutase in hippocampal cells. SIGNIFICANCE: The study has provided preliminary data to elucidate the toxic potential of BP oil spill residues trapped along the Alabama shoreline.


Assuntos
Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Poluição por Petróleo , Poluentes Químicos da Água/toxicidade , Alabama , Animais , Linhagem Celular , Hipocampo/citologia , Humanos , Ratos
14.
Life Sci ; 154: 24-9, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26926078

RESUMO

AIMS: Methamphetamine (Schedule-II drug, U.S. Drug Enforcement Administration) is one of the most abused illicit drug following cocaine, marijuana, and heroin in the USA. There are numerous health impairments and substantial economic burden caused by methamphetamine abuse. Salicylic acid, potent anti-inflammatory drug and a known neuroprotectant has shown to protect against toxicity-induced by other dopaminergic neurotoxins. Hence, in this study we investigated the neuroprotective effects of salicylic acid against methamphetamine-induced toxicity in mice. MAIN METHODS: The current study investigated the effects of sodium salicylate and/or methamphetamine on oxidative stress, monoamine oxidase, mitochondrial complex I & IV activities using spectrophotometric and fluorimetric methods. Behavioral analysis evaluated the effect on movement disorders-induced by methamphetamine. Monoaminergic neurotransmitter levels were evaluated using high pressure liquid chromatography-electrochemical detection. KEY FINDINGS: Methamphetamine caused significant generation of reactive oxygen species and decreased complex-I activity leading to dopamine depletion. Striatal dopamine depletion led to significant behavioral changes associated with movement disorders. Sodium salicylate (50 & 100mg/kg) significantly scavenged reactive oxygen species, blocked mitochondrial dysfunction and exhibited neuroprotection against methamphetamine-induced neurotoxicity. In addition, sodium salicylate significantly blocked methamphetamine-induced behavioral changes related to movement abnormalities. SIGNIFICANCE: One of the leading causative theories in nigral degeneration associated with movement disorders such as Parkinson's disease is exposure to stimulants, drugs of abuse, insecticide and pesticides. These neurotoxic substances can induce dopaminergic neuronal insult by oxidative stress, apoptosis, mitochondrial dysfunction and inflammation. Salicylic acid due to its antioxidant and anti-inflammatory effects could provide neuroprotection against the stimulants or drugs of abuse.


Assuntos
Dopamina/metabolismo , Metanfetamina/toxicidade , Fármacos Neuroprotetores/farmacologia , Ácido Salicílico/farmacologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
Cell Stress Chaperones ; 20(5): 833-41, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26003133

RESUMO

Development of novel anti-cancer drug leads that target regulators of protein homeostasis is a formidable task in modern pharmacology. Finding specific inhibitors of human Heat Shock Factor 1 (hHSF1) has proven to be a challenging task, while screening for inhibitors of human Heat Shock Factor 2 (hHSF2) has never been described. We report the development of a novel system based on an in vivo cell growth restoration assay designed to identify specific inhibitors of human HSF2 in a high-throughput format. This system utilizes a humanized yeast strain in which the master regulator of molecular chaperone genes, yeast HSF, has been replaced with hHSF2 with no detrimental effect on cell growth. This replacement preserves the general regulatory patterns of genes encoding major molecular chaperones including Hsp70 and Hsp90. The controlled overexpression of hHSF2 creates a slow-growth phenotype, which is the basis of the growth restoration assay used for high-throughput screening. The phenotype is most robust when cells are cultured at 25 °C, while incubation at temperatures greater than 30 °C leads to compensation of the phenotype. Overexpression of hHSF2 causes overexpression of molecular chaperones which is a likely cause of the slowed growth. Our assay is characterized by two unique advantages. First, screening takes place in physiologically relevant, in vivo conditions. Second, hits in our screen will be of medically relevant potency, as compounds that completely inhibit hHSF2 function will further inhibit cell growth and therefore will not be scored as hits. This caveat biases our screening system for compounds capable of restoring hHSF2 activity to a physiologically normal level without completely inhibiting this essential system.


Assuntos
Proteínas de Choque Térmico/genética , Ensaios de Triagem em Larga Escala/métodos , Fatores de Transcrição/genética , Proteínas de Choque Térmico/antagonistas & inibidores , Humanos , Chaperonas Moleculares/metabolismo , Organismos Geneticamente Modificados , Saccharomyces cerevisiae , Fatores de Transcrição/antagonistas & inibidores
16.
Toxicol Lett ; 229(2): 349-56, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-24973490

RESUMO

The birth of the twenty first century has provoked a substantial rise in the use of designer drugs, such as synthetic cathinones, because of a decrease in the availability and purity of other drugs of abuse. The khat plant or Catha edulis, contains cathinone, the parent compound. Synthetic cathinones are sold under the name "bath salts" as a ploy to circumvent legislation from banning their use. Constant modification of the chemical structure by covert laboratories allows manufacturers to stay one step ahead of the legal process. Currently, the widespread distribution of "bath salts" has negative consequences for law enforcement officials and public health resources. Comparable mechanisms of action, between the synthetic cathinones and amphetamine, cocaine, and MDMA are attributed to the similarities in their chemical structures. Synthetic cathinone's potent stimulatory effects, coupled with their high abuse potential, and propensity for addiction demands additional pharmacological and toxicological evaluations for these existing and new designer drugs of abuse. If these drugs are designed carefully, they might also have a significant therapeutic value.


Assuntos
Alcaloides/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Drogas Desenhadas/farmacologia , Alcaloides/química , Animais , Catha , Estimulantes do Sistema Nervoso Central/química , Humanos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
17.
Life Sci ; 101(1-2): 37-42, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24560859

RESUMO

AIMS: There is a rapid increase in the use of methylenedioxymethamphetamine (MDMA) and its structural congeners/analogs globally. MDMA and MDMA-analogs have been synthesized illegally in furtive dwellings and are abused due to its addictive potential. Furthermore, MDMA and MDMA-analogs have shown to have induced several adverse effects. Hence, understanding the mechanisms mediating this neurotoxic insult of MDMA-analogs is of immense importance for the public health in the world. MAIN METHODS: We synthesized and investigated the neurotoxic effects of MDMA and its analogs [4-methylenedioxyamphetamine (MDA), 2, 6-methylenedioxyamphetamine (MDMA), and N-ethyl-3, 4-methylenedioxyamphetamine (MDEA)]. The stimulatory or the dopaminergic agonist effects of MDMA and MDMA-analogs were elucidated using the established 6-hydroxydopamine lesioned animal model. Additionally, we also investigated the neurotoxic mechanisms of MDMA and MDMA-analogs on mitochondrial complex-I activity and reactive oxygen species generation. KEY FINDINGS: MDMA and MDMA-analogs exhibited stimulatory activity as compared to amphetamines and also induced several behavioral changes in the rodents. MDMA and MDMA-analogs enhanced the reactive oxygen generation and inhibited mitochondrial complex-I activity which can lead to neurodegeneration. Hence the mechanism of neurotoxicity, MDMA and MDMA-analogs can enhance the release of monoamines, alter the monoaminergic neurotransmission, and augment oxidative stress and mitochondrial abnormalities leading to neurotoxicity. SIGNIFICANCE: Thus, our study will help in developing effective pharmacological and therapeutic approaches for the treatment of MDMA and MDMA-analog abuse.


Assuntos
Comportamento Animal/efeitos dos fármacos , Agonistas de Dopamina/toxicidade , Complexo I de Transporte de Elétrons/metabolismo , N-Metil-3,4-Metilenodioxianfetamina/análogos & derivados , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Masculino , Proteínas Mitocondriais/metabolismo , Oxidopamina , Ratos
18.
Life Sci ; 95(2): 108-17, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24361361

RESUMO

AIMS: The British Petroleum (BP) oil spill has raised several ecological and health concerns. As the first response, BP used a chemical dispersant, Corexit-9500, to disperse the crude oil in the Gulf of Mexico to limit shoreline contamination problems. Nevertheless, portions of this oil/Corexit mixture reached the shoreline and still remain in various Gulf shore environments. The use of Corexit itself has become a significant concern since its impacts on human health and environment is unclear. MAIN METHODS: In this study, in vitro cytotoxic effects of Corexit were evaluated using different mammalian cells. KEY FINDINGS: Under serum free conditions, the LC50 value for Corexit in BL16/BL6 cell was 16 ppm, in 1321N1 cell was 33 ppm, in H19-7 cell was 70 ppm, in HEK293 was 93 ppm, and in HK-2 cell was 95 ppm. With regard to the mechanisms of cytotoxicity, we hypothesize that Corexit can possibly induce cytotoxicity in mammalian cells by altering the intracellular oxidative balance and inhibiting mitochondrial functions. Corexit induced increased reactive oxygen species and lipid peroxide levels; also, it depleted glutathione content and altered catalase activity in H19-7 cells. In addition, there was mitochondrial complex-I inhibition and increase in the pro-apoptotic factors including caspase-3 and BAX expression. SIGNIFICANCE: The experimental results show changes in intracellular oxidative radicals leading to mitochondrial dysfunctions and apoptosis in Corexit treatments, possibly contributing to cell death. Our findings raise concerns about using large volumes of Corexit, a potential environmental toxin, in sensitive ocean environments.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Lipídeos/toxicidade , Poluentes Químicos da Água/toxicidade , Linhagem Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Dose Letal Mediana , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/análise
19.
Virol J ; 7: 147, 2010 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-20604948

RESUMO

BACKGROUND: Human immunodeficiency virus (HIV) infection is associated with an increased risk for human herpes viruses (HHVs) and their related diseases and they frequently cause disease deterioration and therapeutic failures. Methods for limiting the transmission of HHVs require a better understanding of the incidence and infectivity of oral HHVs in HIV-infected patients. This study was designed to determine the seroprevalence of human herpes viruses (CMV, HSV 2, EBV-1, VZV) antibodies and to evaluate their association with age, sex as well as other demographic and behavioral factors. RESULTS: A study of 200 HIV positive patients from Eastern India attending the Calcutta Medical College Hospital, Kolkata, West Bengal, Apex Clinic, Calcutta Medical College Hospital and ART Center, School of Tropical Medicine, Kolkata, West Bengal was done. Serum samples were screened for antibodies to the respective viruses using the indirect ELISA in triplicates.CytoMegalo virus (CMV), Herpes Simplex virus type 2 (HSV-2), Varicella Zoster virus (VZV), and Epstein Barr virus (EBV-1) were detected in 49%, 47%, 32.5%, and 26% respectively. CONCLUSION: This study has contributed baseline data and provided insights in viral OI and HIV co-infection in Eastern India. This would undoubtedly serve as a basis for further studies on this topic.


Assuntos
Soropositividade para HIV/complicações , Infecções por Herpesviridae/epidemiologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Feminino , Anticorpos Anti-HIV/sangue , Soropositividade para HIV/imunologia , Soropositividade para HIV/virologia , Herpesviridae/imunologia , Herpesviridae/isolamento & purificação , Infecções por Herpesviridae/etiologia , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Humanos , Incidência , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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