Avaliação do potencial neuroprotetor do óleo essencial de Citrus limon em hipocampo e corpo estriado de camundongos após convulsões induzidas pela pilocarpina

The seizures can produce neuronal damage in several brain structures. The aim of this study was to investigate the potential neuroprotective effect of essential oil of Citrus limon (EOCL) on the histopathological changes observed in the hippocampus and striatum of mice after seizures induced by pilocarpine. Adult Swiss mice were 2 months old. The animals were divided into four groups. The first group was treated with 0.05% Tween 80 (control group) and the second with pilocarpine (400 mg/kg group P400). The third and fourth group were treated with EOCL (150 mg/kg) and 30 min after received P400 (P400 + EOCL group) or 0.05% Tween 80, respectively. After treatment, all groups were observed for 24 h, then sacrificed and their brains removed for histopathological analysis. The group P400, presented with seizures that progressed to status epilepticus in 75% of animals. Pretreatment with OECL produced a 25% reduction in this index. Groups P400 and P400 + EOCL showed 83.33% and 25% of animals with brain damage in the hippocampus, respectively. In the striatum of group P400 was a compromise of 75%. In turn, in the striatal region of group EOCL P400 + was seen a decrease of 58.34% in this neuronal damage. The seizures induced by pilocarpine are installed by the cholinergic system and produce brain damage. According to our results we suggest that the EOCL may modulate epileptogenesis and promote neuroprotective effects during the seizures in the model investigated.As convulsões podem produzir danos neuronais em diversas estruturas cerebrais. O objetivo desse estudo foi investigar o potencial efeito neuroprotetor do óleo essencial de Citrus limon (OECL) nas alterações histopatológicas observadas no hipocampo e corpo estriado de camundongos após convulsão induzida por pilocarpina. Foram utilizados camundongos Swiss adultos com 2 meses de idade. Os animais foram divididos em 4 grupos. O primeiro grupo foi tratado com Tween 80 0,05% (grupo controle) e o segundo com pilocarpina (400 mg/kg, grupo P400). Já o terceiro e quarto grupo foram tratados com OECL (150 mg/kg), e 30 min depois receberam P400 (grupo OECL + P400) ou Tween 80 0,05% 0.9% (grupo OECL), respectivamente. Após os tratamentos, todos os grupos foram observados durante 24 h e em seguida sacrificados e seus cérebros removidos para as análises histopatológicas. O grupo P400, apresentou convulsões que progrediram para o estado epiléptico em 75% dos animais. O pré-tratamento com OECL produziu uma redução de 25% nesse índice. Os grupos P400 e OECL + P400 apresentaram 83,33% e 25% de animais com lesão cerebral no hipocampo, respectivamente. No corpo estriado dos animais do grupo P400 houve um comprometimento de 75%. Por sua vez, na região estriatal dos animais do grupo OECL + P400 foi visto uma redução de 58,34% nesse comprometimento. As convulsões induzidas pela pilocarpina são instaladas pelo sistema colinérgico e produzem dano cerebral. De acordo com nossos resultados podemos sugerir que o OECL pode modular a epileptogênese e promover ação neuroprotetora durante as convulsões no modelo investigado

Citrus: A Perspective for Developing Phytomedicines for Neurodegenerative Diseases

The antioxidant and anti-inflammatory properties of Citrus flavonoids can play a key role in their activity against several degenerative diseases and particularly brain diseases. In Brazil promising studies deposited in the patents “pharmaceutical formulation” form was obtained from the inclusion of Citrus sinensis L. (orange) essential oil with β-cyclodextrin and Citrus limon (lemon) compounds and their applications in therapy of Alzheimer’s disease. In this chapter, we report activities of active compounds present in the genus Citrus, which include antioxidant, anti-inflammatory, anxiolytic, insecticidal, and anticholinesterase activities. These activities are associated with some neurodegenerative diseases such as Alzheimer’s disease (AD). Pharmaceutical formulations containing such compounds (for example, inhibitors such as acetylcholinesterase (AChE) of C. limon (5,8-dimethoxy-psoralen and 5,7-dimethoxycumarin) and essential oil from C. sinensis oils are reported in this chapter. These results indicate that the effects of the essential oil and substances of Citrus species are very interesting for further isolation of AChE inhibitors that can be used in the formulation of natural products for neurodegenerative diseases

Antioxidant and Antinociceptive Effects of Citrus limon Essential Oil in Mice

The antioxidant and antinociceptive activities of Citrus limon essential oil (EO) were assessed in mice or in vitro tests. EO possesses a strong antioxidant potential according to the scavenging assays. Moreover, it presented scavenger activity against all in vitro tests. Orally, EO (50, 100, and 150 mg/kg) significantly reduced the number of writhes, and, at highest doses, it reduced the number of paw licks. Whereas naloxone antagonized the antinociceptive action of EO (highest doses), this suggested, at least, the participation of the opioid system. Further studies currently in progress will enable us to understand the action mechanisms of EO

Possible oxidative effects of isotretinoin and modulatory effects of vitamins A and C in Saccharomyces cerevisiae

Isotretinoin (ITN), chemically known as 13-cis-retinoic acid, is a part of the broad group of compounds related to vitamin A. It is particularly employed in the treatment of nodular cystic acne and as an inhibitor of proliferation of neoplastic cells, by exerting a regulatory effect on the cell differentiation. This study aimed at investigating the possible oxidative effects of ITN and modulatory effects of vitamins A and C in mutant and non-mutant Saccharomyces cerevisiae strains. In addition, to reconfirm the oxidative effects, five in vitro antioxidant assays were also prepared taking the alpha-tocopherol analogue, trolox as a standard. In vivo study conducted on S. cerevisiae cells was carried out with ITN 20 μg/ml taking hydrogen peroxide (H2O2) as stressor (STR), whereas ITN 5 to 50 μg/ml was considered for in vitro assays taking similar dose of trolox (TRO). Results show ITN to have oxidative effect in both in vitro and in vivo tests. In conclusion, ITN produced oxidative effects and there may be an hypervitaminosis effect with vitamins A and C, thus insinuation to genetic material.Key words: Assay, isotretinoin, vitamin A, vitamin C, oxidative stress

ESTUDO FITOQUÍMICO E ATIVIDADE ANTICOLINESTERÁSICA DA ESPÉCIE Plantago major L.

Plantago major L. is a plant of medicinal interest belonging to the Plantaginaceae family, popularly known as plantain, its leaves are used to treat boils, earache, hoarseness, antiseptic, antibacterial and so on. This work aimed to study the hexane and ethanolic extracts of P. major leaves, identifying the main chemical constituents through chromatographic tests and their anticholinesterase action. The ethanolic and hexane extracts of the leaves were submitted to phytochemical prospection, chromatographic studies and the enzyme assay of acetylcholinesterase inhibition was performed according to the methodology proposed by Ellman. The results of the phytochemical analysis of the extracts showed a variety of secondary metabolites. The acetylcholinesterase enzyme inhibition tests of the leaf extracts showed inhibition percentages of 84.20%, 83.04% for the ethanolic extract and 70.86% for the hexane extract, being satisfactory in relation to the reference values found in the literature.Plantago major L. es una planta de interés medicinal perteneciente a la familia Plantaginaceae, conocida popularmente como plátano, sus hojas se utilizan para tratar forúnculos, dolor de oídos, ronquera, antiséptico, antibacteriano y un largo etcétera. Este trabajo tuvo como objetivo estudiar el hexano y los extractos etanólicos  de las hojas de P. major, identificando los principales constituyentes químicos a través de pruebas cromatográficas y su acción anticolinesterasa. Los extractos etanólico y hexano de las hojas fueron sometidos a prospección fitoquímica, estudios cromatográficos y se realizó el ensayo enzimático de inhibición de acetilcolinesterasa según la metodología propuesta por Ellman. Los resultados del análisis fitoquímico de los extractos mostraron una variedad de metabolitos secundarios. Las pruebas de inhibición de la enzima acetilcolinesterasa de los extractos foliares mostraron porcentajes de inhibición del 84,20%, 83,04% para el extracto etanólico y 70,86% para el extracto de hexano, siendo satisfactorios en relación con los valores de referencia encontrados en la literaturaA Plantago major L. é uma planta de interesse medicinal pertencente à família Plantaginaceae, sendo conhecida popularmente como tanchagem. Suas folhas são empregadas para tratamento de furúnculos, dor de ouvido, rouquidão, antissépticas, antibacterianas e etc. Este trabalho teve como objetivo estudar os extratos hexânico e etanólico das folhas da P. major, identificando os principais constituintes químicos através de testes cromatrográficos e sua ação anticolinesterásica. Os extratos etanólicos e hexânicos das folhas foram submetidos a prospecção fitoquímica, estudos cromatográficos e o ensaio enzimático de inibição da acetilcolinesterase realizado conforme a metodologia proposta por Ellman. Os resultados da análise fitoquímica dos extratos mostram uma variedade de metabólitos secundários e os testes de inibição da enzima acetilcolinesterase apresentaram porcentagens de inibição de 84,20% e 83,04% para o extrato etanólico nas concentrações de 1mg/mL e 0,5mg/mL, respectivamente e, 70,86% na concentração de 1mg/mL para o extrato hexânico, sendo satisfatórios em relação aos valores de referência encontrados na literatura

A Química Quântica na compreensão de teorias de Química Orgânica

Quantum chemical calculations were performed in order to obtain molecular properties such as electronic density, dipole moment, atomic charges, and bond lengths, which were compared to qualitative results based on the theories of the organic chemistry. The quantum chemistry computational can be a useful tool to support the main theories of the organic chemistry

Composição química e atividade anticolinesterásica de uma fração ativa do extrato de folhas de Citrus limon (L.) Burm

This paper describes the chemical composition and acetylcholinesterase inhibition of an active chromatographic fraction of the EtOAc extract of Citrus limon leaves. The composition of the active fraction presented a mixture of two coumarins, 5,8-dimethoxy-psoralen and 5,7- dimethoxycoumarin, identified by ¹H and ¹³C NMR data analysis, including DEPT, COSY, HMBC and HSQC experiments. It was also demonstrated that this mixture presents qualitative and quantitative AChE inhibition. In vitro studies indicated a CE50 value of 340 µg/mL with 95% of confidence. In vivo studies (10 and 25 mg/kg) revealed inhibition of 30.09 and 30.06% of AChE activity in relation to neostigmine, respectively