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1.
Drug Chem Toxicol ; 47(5): 507-515, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38326987

RESUMO

Tobacco stalk is a cellulose-rich material and a sustainable alternative to be applied as a plant-based nanofibrillated cellulose (NFC) source. NFC use has garnered attention in the development of oral pharmaceutical forms, despite concerns about its safety due to the adverse effects of nicotine on health. Therefore, we aimed at establishing the safety of NFC derived from tobacco stalk for its potential use as a novel pharmaceutical excipient, exploring its potential functions for tablet production. We conducted acute and subchronic oral toxicity tests in adult female Wistar rats. Initially, individual animals received sequential doses (175-5,000 mg·kg-1) for 24 hours followed by a careful observation of any toxic effects. Subsequently, 20 rats were divided into four groups for a subchronic assay, evaluating toxicity signs, body weight changes, hematological, biochemical, and histopathological parameters. No deaths or other clinical toxicity signs were observed in either the acute or the subchronic assays. We noticed a significant reduction in body weight gain (p < 0.05) after 14 days. We found statistical differences for hematological and biochemical parameters, unrelated to dosage. There were no observed toxic effects, and tobacco stalk ingestion did not adversely affect organ morphology in the histopathological evaluation. The oral administration of NFC at 5,000 mg·kg-1 per day for 28 days was well-tolerated by treated rats, with no reported deaths. In conclusion, NFC derived from tobacco stalk has shown to be a sustainable and safe alternative for use as an excipient at experimental doses, demonstrating compatibility with its proposed applications.


Assuntos
Celulose , Excipientes , Nicotiana , Ratos Wistar , Animais , Feminino , Celulose/toxicidade , Celulose/administração & dosagem , Celulose/química , Excipientes/toxicidade , Excipientes/química , Administração Oral , Testes de Toxicidade Subcrônica , Ratos , Testes de Toxicidade Aguda , Nanofibras/toxicidade , Química Verde , Relação Dose-Resposta a Droga
3.
Int J Mol Sci ; 24(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37762565

RESUMO

Phytoestrogens, such as isoflavones, are bioactive compounds found in plants with defense and protection functions. In the human body, they simulate the behavior of the hormone estradiol and can modulate the function of the male hypothalamic-pituitary-gonadal axis. This study aims to describe the effects of genistein on sperm quality of Wistar rats (male/adult) after a short oral administration protocol (50 mg/day, for 5 days), focusing on mitochondrial function. No signs of toxicity were observed in the animals during the period. The testicular mass of rats from the genistein-treated group was lower than that from the control group. Isoflavone increased the number of viable Leydig and Sertoli cells, spermatogonia, and primary spermatocytes in the treated group. The rounded spermatid count was similar to the control group, and a decrease in elongated spermatids was observed in the treated group. Genistein treatment increased plasma testosterone levels in the treated group. To the best of our knowledge, this is the first report of an in vivo short protocol demonstrating that genistein administration stimulates the overall oxygen consumption in rat seminal samples. Therefore, genistein induced a pro-spermatogenesis effect, enhanced plasma testosterone levels, and increased oxygen consumption, improving sperm mitochondrial efficiency. Similar protocols can be explored in animal and human infertility issues.


Assuntos
Genisteína , Isoflavonas , Adulto , Humanos , Masculino , Animais , Ratos , Ratos Wistar , Genisteína/farmacologia , Sêmen , Espermatozoides , Mitocôndrias , Testosterona
4.
Alcohol Clin Exp Res (Hoboken) ; 47(6): 1039-1054, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37095068

RESUMO

Although Place Conditioning (PC) has been used to study the motivational effects of alcohol for almost 50 years, variables and situations in which alcohol induces PC in rats are still unclear, especially for short PC protocols (up to 10 conditioning trials). The aim of this systematic review was to predict primary outcomes (namely, conditioning failure, conditioned place aversion (CPA), and conditioned place preference (CPP)) of alcohol-induced PC with male outbred rats. We sought relevant records in PUBMED and two other sources. Two reviewers independently assessed records for eligible articles (those meeting all inclusion criteria), selected alcohol-induced PC experiments (those meeting no exclusion criteria) from eligible articles, extracted data, and assessed the quality of included studies. We then conducted a predictive analysis of outcomes by examining procedure-outcome relations according to variables known to affect associative learning, alcohol interventions in rats, and PC interventions themselves. We selected 192 experiments (133 short protocols, 27 long protocols, and 32 protocols with alcohol pre-exposure) from 62 articles to compose the review. Rates of conditioning failure are mainly predicted by interactions of alcohol dose and the number of habituation sessions and conditioning trials. Different conditions (housing systems) and characteristics (age and weight) of animals predict CPA and CPP: higher rates of CPA are predicted by single-housed, older, and heavier animals, while higher rates of CPP are predicted by group-housed, younger, and lighter animals. We recommend settings for CPP induction in short protocols, discuss the broad theoretical and translational consequences of the predictive analysis for the use of PC in alcohol research, and specify variables needing more careful investigation. This review could improve our understanding of the results of alcohol-induced PC with rats, refine our understanding of the motivational function of alcohol and alcohol-seeking behavior triggered by environmental contexts, and open new avenues of research on their neurobiological basis.

5.
Biomed Chromatogr ; 37(4): e5586, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683129

RESUMO

Vancomycin is used as an antimicrobial agent for the treatment of severe gram-positive infections. The importance of therapeutic monitoring of antimicrobials has led to the development of more specific sample preparation techniques capable of identifying with accuracy the concentration of this substance in the organism. An aliquot of 10 µl of plasma was transferred to Whatman 903 paper and dried at room temperature. The extraction method was performed by cutting and transferring the paper to a microtube and adding sodium phosphate buffer and internal standard. The mixture was shaken and centrifuged, and a 5-µl aliquot was injected into the analytical system. The optimization of the main parameters that can influence the extraction efficiency was performed using multivariate approaches to obtain the best conditions. The method developed was validated, providing coefficients of determination higher than 0.994 and a lower limit of quantification of 1 mg/L. Within- and between-run precision ranged from 11.4 to 17.30% and from 6.65 to 13.51%, respectively. This method was successfully applied to 75 samples of patients undergoing vancomycin therapy. The method was rapid, simple, and environmentally friendly with satisfactory analytical performance and was advantageous over the laborious and time-consuming methodologies used in therapeutic drug monitoring routine analyses.


Assuntos
Espectrometria de Massas em Tandem , Vancomicina , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Plasma , Monitoramento de Medicamentos/métodos , Teste em Amostras de Sangue Seco/métodos , Imunoensaio/métodos , Reprodutibilidade dos Testes
6.
Mol Brain ; 15(1): 95, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36434658

RESUMO

Activation of nociceptin opioid peptide receptors (NOP, a.k.a. opioid-like receptor-1, ORL-1) by the ligand nociceptin/orphanin FQ, leads to G protein-dependent regulation of Cav2.2 (N-type) voltage-gated calcium channels (VGCCs). This typically causes a reduction in calcium currents, triggering changes in presynaptic calcium levels and thus neurotransmission. Because of the widespread expression patterns of NOP and VGCCs across multiple brain regions, the dorsal horn of the spinal cord, and the dorsal root ganglia, this results in the alteration of numerous neurophysiological features. Here we review the regulation of N-type calcium channels by the NOP-nociceptin system in the context of neurological conditions such as anxiety, addiction, and pain.


Assuntos
Canais de Cálcio Tipo N , Doenças do Sistema Nervoso , Humanos , Analgésicos Opioides , Cálcio , Receptor de Nociceptina
7.
Biomed Chromatogr ; 36(12): e5487, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36001303

RESUMO

The combination of different advanced analytical techniques makes it possible to determine the concentrations of neurotransmitters in various biological matrices, providing a complex and comprehensive study of the effects of psychoactive substances. The present study aimed to develop and validate a fast and simple analytical method for the determination of acetylcholine, serotonin, γ-aminobutyric acid, glutamate, dopamine and metabolites in rats brain tissue by liquid chromatography coupled to tandem mass spectrometry. The brain was homogenized and aliquots of the sample, dopamine-d4 , and acetone were added to a tube and then vortexed and centrifuged. The supernatant was collected and dried. The residue was reconstituted and injected. The LLOQ ranged from 0.001 to 1 µg/g; the intra-run precision ranged from 0.47 to 11.52%; the inter-run precision ranged from 0.68 to 17.54%; and the bias ranged from 89.10 to 109.60%. As proof of concept, the method was applied to animals exposed to the synthetic cathinone 4'-fuoro-α-pyrrolidinohexanophenone (300 mg/kg). In addition, the workflow proved to be simple, rapid and useful to estimate the concentration of neurotransmitters. This analytical tool can be used to support the investigation of the changes in the neurochemical profile for the characterization of the mechanism of action of psychoactive substances, as well as both neurological and psychiatric diseases.


Assuntos
Dopamina , Espectrometria de Massas em Tandem , Animais , Ratos , Espectrometria de Massas em Tandem/métodos , Dopamina/análise , Cromatografia Líquida/métodos , Neurotransmissores/análise , Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes
8.
Toxicol Mech Methods ; 32(9): 705-715, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35410575

RESUMO

Schizophrenia is a psychiatric disorder that affects 1% of the world population and is treated with antipsychotics, which may induce important biochemical and hematological alterations. Since it is necessary to verify the safety of new molecules with antipsychotic potential, the present study aimed to evaluate the oral toxicity of PT-31, a putative α2-adrenoreceptor agonist, after acute (2000 mg/kg) and repeated doses (28 days) gavage treatment, in three different doses: minimum effective dose in animal models (10 mg/kg), twice the dose (20 mg/kg), and four times the dose (40 mg/kg), as recommended by the OECD guidelines. Balb/C female adult mice were used, and biochemical, hematological, and histopathological analyses were performed. PT-31 10 and 20 mg/kg did not cause biochemical alterations related to hepatic and renal toxicity, and neither altered glycemic and lipid profiles. The preclinical dose of PT-31 also did not promote mice histopathological changes in the liver, kidney, and brain. In the hematimetric parameters, PT-31 only increased HGB at 20 mg/kg, and MCH and MCHC at 40 mg/kg. However, all the tested doses of PT-31 showed platelet increase, which must be better investigated. Therefore, further studies are needed to investigate the safety of PT-31 as a potential antipsychotic drug.


Assuntos
Antipsicóticos , Animais , Antipsicóticos/toxicidade , Feminino , Humanos , Rim , Lipídeos , Fígado , Camundongos , Testes de Toxicidade Aguda
9.
Naunyn Schmiedebergs Arch Pharmacol ; 395(7): 803-813, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35394134

RESUMO

Curcumin has protective actions in neuropsychiatric disorders, acting as a neuroprotective agent. As a first approach, the study aimed at a systematic review of the potential effects of curcumin on cognitive performance for attention-deficit-hyperactivity disorder (ADHD). This research was carried out in the databases of PubMed, Embase, SciELO, the Cochrane Central Register of Controlled Trials (CENTRAL), the Web of Science, and the Grey literature. Upon discovering the scarcity of relevant studies, and knowing that curcumin might have an ADHD hyperactive and anxious behavior, the study proposed to evaluate the effects of curcumin in an ADHD phenotype of spontaneously hypertensive Wistar rats (SHR). No studies were found that related to curcumin and ADHD. Fifteen SHRs were then divided into separate groups that received water (1 mg/kg/day), curcumin (50 mg/kg/day), or methylphenidate (1 mg/kg/day) for 42 days. Behavioral tests to assess activity (Open Field Test), anxiety and impulsivity (Elevated Plus-Maze, and Social Interaction), and memory (Y-Maze, and the Object Recognition Test) were all performed. The animals that were treated with curcumin showed less anxious and hyperactive behavior, as seen in the Open Field Test and the Social Interaction Test. Anxious behavior was measured by the EPM and was not modulated by any treatment. The results of the Y-Maze Test demonstrated that curcumin improved spatial memory. In the Object Recognition Test, neither the short nor the long-term memory was improved. The treatments that were used in this study beneficially modulated the anxious and hyperactive behavior of the SHR.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Estimulantes do Sistema Nervoso Central , Curcumina , Animais , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Escala de Avaliação Comportamental , Estimulantes do Sistema Nervoso Central/farmacologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Curcumina/farmacologia , Curcumina/uso terapêutico , Modelos Animais de Doenças , Atividade Motora , Ratos , Ratos Endogâmicos SHR , Ratos Wistar
10.
Int. arch. otorhinolaryngol. (Impr.) ; 26(1): 167-177, Jan.-Mar. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1364916

RESUMO

Abstract Introduction Chloroquine and hydroxychloroquine are antimalarial drugs widely used in the treatment of rheumatic diseases. With the global pandemic caused by the new coronavirus, there was an increase in the prescription of these drugs, which led to a major concern regarding their ototoxic effects. Objectives The objective of the present study was to assess existing scientific evidence about the toxic effects of chloroquine and hydroxychloroquine on the peripheral and/or central auditory system. Data Synthesis A systematic literature review was performed by searching the PubMed (Medline), Scopus, Web of Science, LILACS, and SciELO electronic databases, in a search of articles that fullfiled the predefined inclusion and exclusion criteria. The review was conducted in three phases and, in all of them, analyses were performed by two independent researchers. Disagreements were discussed with a third researcher until a consensus was reached. A total of 437 articles were found and 8 were included in this review. Seven of the included studies reported hearing loss in their samples and presented a diagnostic hypothesis of ototoxicity induced by chloroquine or hydroxychloroquine. The most common type of hearing loss was sensorineural, with varying laterality and degrees of severity. The most frequently used audiological test was pure tone audiometry, and only two studies assessed brainstem evoked responses. Conclusion The scientific evidence compiled in this research showed that chloroquine and hydroxychloroquine have an ototoxic effect in the peripheral auditory system. These drugs can cause cochlear damage, including changes in the stria vascularis and lesions in sensory hair cells.

11.
Braz. j. otorhinolaryngol. (Impr.) ; Braz. j. otorhinolaryngol. (Impr.);88(1): 28-35, Jan.-Feb. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1364575

RESUMO

Abstract Introduction Considering that previous studies suggest that pesticides may cause hearing disorders in humans, as well as the lack of studies proving the specific mechanisms of injury and the difficulty of separating concomitant etiological factors of the hearing damage, such as noise and vibration, it is important to develop studies using animal models to elucidate the effects of exposure to those substances isolated from other hearing damage etiologies. Objective To evaluate if the exposure to a dichlorvos based organophosphorus insecticide may induce ototoxicity. Methods 36 male Wistar rats were assigned to 3 groups (12 rats/group): control (exposed to water), positive control (treated with cisplatin to induce hearing damage) and experimental (exposed to dichlorvos based organophosphorus insecticide). The amplitude of distortion product otoacoustic emissions in the frequencies of 4, 6, 8, 10 and 12 kHz was evaluated before and after exposure, as well as systemic toxicity signs, body mass gain and plasma cholinesterase. Open field and plus maze tests were performed in 24 rats: experimental (n = 8), control (n = 8) and positive control group (n = 8 introduced new rats to induce anxiolytic activity) to evaluate the locomotor activity and anxiety, respectively. Results There was no significant change in body mass gain and plasma cholinesterase in the dichlorvos based organophosphorus insecticide group, however, the animals showed transient piloerection, depression and dyspnea during exposure. The behavior was not affected in any group. The frequencies of 8 and 10 kHz were significantly affected bilaterally in the insecticide group, which also showed a significant difference of the control in 10 kHz on the right and 8 and 10 kHz on the left ear. Conclusion Subchronic inhalation exposure to dichlorvos based organophosphorus insecticide induced ototoxicity in the cochlear function of rats without relevant systemic toxicity.


Resumo Introdução Considerando que estudos anteriores sugerem que pesticidas podem causar distúrbios auditivos em humanos, além da falta de estudos que comprovem os mecanismos específicos de lesão e a dificuldade em separar fatores etiológicos concomitantes dos danos auditivos, como ruído e vibração, é importante desenvolver estudos que usem modelos animais para elucidar os efeitos da exposição a substâncias isoladas de outras etiologias de danos auditivos. Objetivo Avaliar se a exposição a um inseticida organofosforado baseado em diclorvos pode induzir ototoxicidade. Método Foram divididos em 3 grupos 36 ratos Wistar machos (12 ratos/grupo): controle (exposto à água), controle positivo (tratado com cisplatina para induzir dano auditivo) e experimental (exposto ao inseticida). A amplitude das emissões otoacústicas por produto de distorção nas frequências de 4, 6, 8, 10 e 12 kHz foi avaliada antes e após a exposição, bem como sinais de toxicidade sistêmica, ganho de massa corporal e colinesterase plasmática. Os testes Open Field e Plus Maze foram feitos em 24 ratos: experimental (n = 8), controle (n = 8) e grupo controle positivo (n = 8, introduziu novos ratos para induzir atividade ansiolítica) para avaliar a atividade locomotora e a ansiedade, respectivamente. Resultados Não houve alteração significativa no ganho de massa corporal e colinesterase plasmática no grupo experimental; entretanto, os animais apresentaram piloereção transitória, depressão e dispneia durante a exposição. O comportamento não foi afetado em qualquer grupo. As frequências de 8 e 10 kHz foram significativamente afetadas bilateralmente no grupo exposto ao inseticida, o qual também mostrou uma diferença significativa do controle em 10 kHz na orelha direita e 8 e 10 kHz na orelha esquerda. Conclusão A exposição subcrônica inalatória de inseticida organofosforado baseado em diclorvos induziu ototoxicidade na função coclear de ratos sem toxicidade sistêmica relevante.

12.
Int Arch Otorhinolaryngol ; 26(1): e167-e177, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35096175

RESUMO

Introduction Chloroquine and hydroxychloroquine are antimalarial drugs widely used in the treatment of rheumatic diseases. With the global pandemic caused by the new coronavirus, there was an increase in the prescription of these drugs, which led to a major concern regarding their ototoxic effects. Objectives The objective of the present study was to assess existing scientific evidence about the toxic effects of chloroquine and hydroxychloroquine on the peripheral and/or central auditory system. Data Synthesis A systematic literature review was performed by searching the PubMed (Medline), Scopus, Web of Science, LILACS, and SciELO electronic databases, in a search of articles that fullfiled the predefined inclusion and exclusion criteria. The review was conducted in three phases and, in all of them, analyses were performed by two independent researchers. Disagreements were discussed with a third researcher until a consensus was reached. A total of 437 articles were found and 8 were included in this review. Seven of the included studies reported hearing loss in their samples and presented a diagnostic hypothesis of ototoxicity induced by chloroquine or hydroxychloroquine. The most common type of hearing loss was sensorineural, with varying laterality and degrees of severity. The most frequently used audiological test was pure tone audiometry, and only two studies assessed brainstem evoked responses. Conclusion The scientific evidence compiled in this research showed that chloroquine and hydroxychloroquine have an ototoxic effect in the peripheral auditory system. These drugs can cause cochlear damage, including changes in the stria vascularis and lesions in sensory hair cells.

13.
Drug Chem Toxicol ; 45(2): 822-833, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32552192

RESUMO

Meloxicam is the non-steroidal anti-inflammatory drug most used in small animals; however, studies on genotoxicity, oxidative stress, and histopathologic alterations in cardiac tissue are limited, especially at therapeutical doses used in these animals. This study evaluated the toxic effects caused by the treatment involving repeated low at higher doses of meloxicam in mice, by genotoxicity, oxidative stress, and histopathological parameters. Mice (CF1, male) received, by gavage, meloxicam at the therapeutic dose indicated for small animals (0.1 mg/kg) and at higher doses (0.5 and 1 mg/kg) for 28 days. Later, they were euthanized for blood and organ analysis. Oxidative stress was analyzed by the plasma ferric reduction capacity (FRAP) and catalase, and genotoxicity, by the comet assay and the micronucleus test. Heart, liver, lung, and kidney tissues were analyzed by the histology, and stomach and duodenum were analyzed with a magnifying glass. The relative weight of organs did not present significant alterations. However, congestion of duodenum vessels was observed at the three tested doses and caused hyperemia of stomach mucosa at 1 mg/kg. In the heart histology there was a reduction in the number of cardiomyocytes, accompanied by an increase in cell diameter (possible cell hypertrophy) dose-dependent. The highest tested dose of meloxicam also increased the DNA damage index, without alterations in the micronucleus test. Meloxicam did not affect the catalase activity but increased the FRAP (1 mg/kg). Meloxicam at the dose prescribed for small animals could potentially cause cardiac histopathologic alterations and genotoxic effects.


Assuntos
Dano ao DNA , Coração , Animais , Ensaio Cometa , Fígado , Masculino , Meloxicam/toxicidade , Camundongos , Testes para Micronúcleos
14.
Front Immunol ; 13: 1096312, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36733394

RESUMO

In this study we explored the previously established leishmanicidal activity of a complementary set of 24 imidazolium salts (IS), 1-hexadecylimidazole (C16Im) and 1-hexadecylpyridinium chloride (C16PyrCl) against Leishmania (Leishmania) amazonensis and Leishmania (Leishmania) infantum chagasi. Promastigotes of L. amazonensis and L. infantum chagasi were incubated with 0.1 to 100 µM of the compounds and eight of them demonstrated leishmanicidal activity after 48 h - C10MImMeS (IC50 L. amazonensis = 11.6), C16MImPF6(IC50 L. amazonensis = 6.9), C16MImBr (IC50 L. amazonensis = 6), C16M2ImCl (IC50 L. amazonensis = 4.1), C16M4ImCl (IC50 L. amazonensis = 1.8), (C10)2MImCl (IC50 L. amazonensis = 1.9), C16Im (IC50 L. amazonensis = 14.6), and C16PyrCl (IC50 L. amazonensis = 4).The effect of IS on reactive oxygen species production, mitochondrial membrane potential, membrane integrity and morphological alterations of promastigotes was determined, as well as on L. amazonensis-infected macrophages. Their cytotoxicity against macrophages and human erythrocytes was also evaluated. The IS C10MImMeS, C16MImPF6, C16MImBr, C16M2ImCl, C16M4ImCl and (C10)2MImCl, and the compounds C16Im and C16PyrCl killed and inhibited the growth of promastigote forms of L. amazonensis and L. infantum chagasi in a concentration-dependent manner, contributing to a better understanding of the structure-activity relationship of IS against Leishmania. These IS induced ROS production, mitochondrial dysfunction, membrane disruption and morphological alterations in infective forms of L. amazonensis and killed intracellular amastigote forms in very low concentrations (IC50 amastigotes ≤ 0.3), being potential drug candidates against L. amazonensis.


Assuntos
Antiprotozoários , Leishmania infantum , Leishmania mexicana , Animais , Camundongos , Humanos , Sais/farmacologia , Antiprotozoários/farmacologia , Camundongos Endogâmicos BALB C , Estresse Oxidativo
15.
Braz J Otorhinolaryngol ; 88(1): 28-35, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32532628

RESUMO

INTRODUCTION: Considering that previous studies suggest that pesticides may cause hearing disorders in humans, as well as the lack of studies proving the specific mechanisms of injury and the difficulty of separating concomitant etiological factors of the hearing damage, such as noise and vibration, it is important to develop studies using animal models to elucidate the effects of exposure to those substances isolated from other hearing damage etiologies. OBJECTIVE: To evaluate if the exposure to a dichlorvos based organophosphorus insecticide may induce ototoxicity. METHODS: 36 male Wistar rats were assigned to 3 groups (12 rats/group): control (exposed to water), positive control (treated with cisplatin to induce hearing damage) and experimental (exposed to dichlorvos based organophosphorus insecticide). The amplitude of distortion product otoacoustic emissions in the frequencies of 4, 6, 8, 10 and 12kHz was evaluated before and after exposure, as well as systemic toxicity signs, body mass gain and plasma cholinesterase. Open field and plus maze tests were performed in 24 rats: experimental (n=8), control (n=8) and positive control group (n=8 introduced new rats to induce anxiolytic activity) to evaluate the locomotor activity and anxiety, respectively. RESULTS: There was no significant change in body mass gain and plasma cholinesterase in the dichlorvos based organophosphorus insecticide group, however, the animals showed transient piloerection, depression and dyspnea during exposure. The behavior was not affected in any group. The frequencies of 8 and 10kHz were significantly affected bilaterally in the insecticide group, which also showed a significant difference of the control in 10kHz on the right and 8 and 10kHz on the left ear. CONCLUSION: Subchronic inhalation exposure to dichlorvos based organophosphorus insecticide induced ototoxicity in the cochlear function of rats without relevant systemic toxicity.


Assuntos
Diclorvós , Inseticidas , Animais , Diclorvós/toxicidade , Exposição por Inalação , Inseticidas/toxicidade , Masculino , Compostos Organofosforados , Emissões Otoacústicas Espontâneas , Ratos , Ratos Wistar
16.
Rev. CEFAC ; 24(2): e4522, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1406683

RESUMO

ABSTRACT Purpose: to evaluate possible ototoxicity secondary to exposure to a combination of pesticides (dichlorvos and cypermethrin based insecticides). Methods: the Wistar rats were divided into 3 groups (12 animals per group): control (water), positive control for hearing damage (cisplatin) and experimental (exposed to dichlorvos and cypermethrin). The amplitude of distortion product otoacoustic emissions was assessed before and after the exposure. Systemic toxicity signs were also evaluated (clinical signs, weight gain and plasma cholinesterase). Wilcoxon test analyzed the post-exposure amplitudes compared to pre-exposure and Kruskal Wallis following Dunn's post hoc tests analyzed the amplitudes' variation. Normally distributed variables were evaluated by Student's t test. Results: body weight and plasma cholinesterase values were similar comparing the pre and post exposure in the experimental group. The control group did not manifest significant amplitude reduction of otoacoustic emissions between the pre and post evaluation. In the group exposed to cisplatin there was a significant reduction in amplitudes at 12 kHz on the right (p = 0.006; Wilcoxon) and 4 kHz on the left (p = 0.032; Wilcoxon). In the group exposed to pesticides, there was a significant reduction in the right ear at 4 kHz (p = 0.034; Wilcoxon) and 8 kHz (p = 0.019; Wilcoxon) and in the left ear at 4 kHz (p = 0.007; Wilcoxon), 6 kHz (p = 0.023; Wilcoxon), 8 kHz (p = 0.045; Wilcoxon) and 12 kHz (p = 0.028; Wilcoxon). Conclusion: there was ototoxicity in the experimental group, without a relevant systemic toxicity.

17.
J Voice ; 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34782225

RESUMO

The literature has been shown that exposition by inhalation to chemical compounds can cause vocal disorders and dysphagia in humans, in addition to other symptoms that are manifested according to the type, concentration and duration of exposure to the substance. Cypermethrin and dichlorvos are pesticides widely used in agriculture, public health, veterinary, and home environments. Despite the scientific evidence that cypermethrin and dichlorvos can cause neurodegenerative damage and motor alterations, there are no studies evaluating the toxic effects of these pesticides on the morphology of structures responsible for vocal mobility, especially to the Recurrent Laryngeal Nerve (RLN). Considering the association between vocal disorders in humans and variations in RLN and morphometry, the aim of this study was to evaluate the possible alterations in the microstructure of RLN secondary to subchronic exposure to cypermethrin (pyrethroid) and dichlorvos (organophosphate) in Wistar rats. The experimental protocol (approved by CEUA-UFCSPA: 321/15 and 323/15) consisted of 15 male Wistar rats, allocated in 3 groups: Control (n = 5, exposed to water), Cypermethrin (n = 5, exposed to cypermethrin - 1/10 of the inhalation median lethal concentration [LC50] - 0.25 mg/L) and dichlorvos (n = 5, exposed to dichlorvos - 1/10 of the LC50 - 1.5 mg/L). Inhalation exposure was performed for 4 hours, 5 times per week, for 6 weeks. The nerves were collected, histologically processed and analyzed using morphometric parameters measured using ZEN 2.6 (Zeiss - Germany). The cypermethrin and dichlorvos groups showed significant changes (P < 0.001, ANOVA) in the g-ratio and in the thickness of the myelin sheath of the RLN when compared to the control animals, however, none of the other parameters evaluated showed statistically significant differences. These findings indicate that repeated inhalation exposure to commercial products of cypermethrin and dichlorvos is able to modify the structure of the RLN and possibly generating vocal changes and / or dysphagia.

18.
IET Nanobiotechnol ; 15(6): 532-544, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34694744

RESUMO

Herpes simplex virus (HSV) 1 and 2 are viruses that infect individuals worldwide and for which there is no cure or vaccine available. The protective response against herpes is mostly mediated by CD8 T lymphocytes that respond to the immunodominant SSIEFARL epitope. However, there are some obstacles concerning the use of free SSIEFARL for vaccine or immunotherapy. The aim of this study was to evaluate the feasibility of nanoencapsulation of SSIEFARL and its immunostimulatory properties. Nano/SSIEFARL was produced by interfacial polymerization in methylmetacrylate, and the physico-chemical properties, morphology and immunobiological parameters were evaluated. To evaluate the ex vivo capacity of Nano/SSIEFARL, we used splenocytes from HSV-1-infected mice to enhance the frequency of SSIEFARL-specific CD8 T lymphocytes. The results indicate that Nano/SSIEFARL has a spherical shape, an average diameter of 352 ± 22 nm, the PDI was 0.361 ± 0.009 and is negatively charged (-26.30 ± 35). The stability at 4°C was 28 days. Also, Nano/SSIEFARL is not toxic for cells at low concentrations in vitro and it is taken up by JAWS II dendritic cells. No histopathological changes were observed in kidneys, liver and lymph nodes of animals treated with Nano/SSIEFARL. Nan/SSIEFARL increased the production of IL-1ß, TNF-α and IL-12 by the dendritic cells. Finally, Nano/SSIEFARL expanded the frequency of SSIEFARL-specific CD8+T lymphocytes at the same rate as free SSIEFARL. In conclusion all data together indicate that SSIEFARL is suitable for nanoencapsulation, and the system produced presents some immunoadjuvant properties that can be used to improve the immune response against herpes.


Assuntos
Herpesvirus Humano 1 , Nanopartículas , Animais , Linfócitos T CD8-Positivos , Epitopos Imunodominantes , Camundongos , Camundongos Endogâmicos C57BL
20.
Neurochem Res ; 46(5): 1092-1100, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33544325

RESUMO

Chronic opioid use changes brain chemistry in areas related to reward processes, memory, decision-making, and addiction. Both neurons and astrocytes are affected, ultimately leading to dependence. Passiflora incarnata L. (Passifloraceae) is the basis of frequently used herbals to manage anxiety and insomnia, with proven central nervous system depressant effects. Anti-addiction properties of P. incarnata have been reported. The aim of this study was to investigate the effect of a commercial extract of Passiflora incarnata (Sintocalmy®, Aché Laboratory) in the naloxone-induced jumping mice model of morphine withdrawal. In addition, glial fibrillary acidic protein (GFAP) and S100 calcium-binding protein B (S100B) levels were assessed in the frontal cortex and hippocampus, and DNA damage was verified on blood cells. In order to improve solubilization a Sintocalmy methanol extract (SME) was used. SME is mainly composed by flavonoids isovitexin and vitexin. The effects of SME 50, 100 and 200 mg/kg (i.p.) were evaluated in the naloxone-induced withdrawal syndrome in mice. SME 50 and SME 100 mg/kg decreased naloxone-induced jumping in morphine-dependent mice without reducing locomotor activity. No alterations were found in GFAP levels, however SME 50 mg/kg prevented the S100B increase in the frontal cortex and DNA damage. This study shows anti-addiction effects for a commercial standardized extract of P. incarnata and suggests the relevance of proper clinical assessment.


Assuntos
Ansiolíticos/uso terapêutico , Morfina/efeitos adversos , Extratos Vegetais/uso terapêutico , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Animais , Dano ao DNA/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Dependência de Morfina/tratamento farmacológico , Naloxona/uso terapêutico , Passiflora , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo
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