ABSTRACT
El presente es un estudio experimental prospectivo, realizado en la Facultad de Farmacia y Bioquímica de la Universidad Nacional Mayor de San Marcos, donde se determinó el efecto antinflamatorio y analgésico del extracto etanólico de Dalea isidori Barneby "Yerbechil". Para evaluar el efecto antiinflamatorio se empleó el método de edema plantar inducido por λ carragenina, utilizándose 36 ratas albinas (Holtzman) divididas en un grupo control, tres grupos para dosis diferentes del extracto (125 mg/Kg, 250 mg/Kg y 500 mg/Kg) y dos grupos para fármacos patrones (AAS 50 mg/Kg, naproxeno 50 mg/Kg); empleándose un pletismómetro digital PANLAB LE7500. El mayor efecto antiinflamatorio se evidenció a las dosis de 250mg/kg. El efecto analgésico se evaluó con el método de retirada de la cola (Tail-Flick), empleándose 36 ratones Balb/c, divididos en dos grupos para fármacos patrones (tramadol 20 mg/Kg y paracetamol 400mg/Kg) y cuatro grupos para dosis diferentes del extracto (125 mg/Kg, 250mg/Kg, 500 mg/Kg y 750 mg/Kg); cuantificándose el efecto analgésico con un medidor Tail-Flick PANLAB LE7106. El mayor efecto analgésico se evidenció a las dosis de 125 mg/Kg y 250 mg/Kg. Finalmente, según la guía 23 de la OECD, se determinó un DL50 oral mayor a 5000 mg/Kg para el extracto etanólico de Dalea isidori Barneby.
Subject(s)
Animals , Mice , Rats , Plant Extracts , Analgesics , Anti-Inflammatory Agents , Chromatography , FabaceaeABSTRACT
Resumen:Los efectos de los insecticidas sobre las abejas han cobrado gran atención a nivel mundial, sin embargo, son pocos los estudios sobre el efecto de estos agroquímicos en abejas Neotropicales. Bombus atratus es una especie neotropical, distribuida ampliamente en los Andes y es considerado un polinizador importante de ecosistemas y agroecosistemas altoandinos. Sin embargo, al igual que muchas especies silvestres, se desconoce el efecto de los insecticidas en B. atratus. Teniendo en cuenta lo anterior, el presente trabajo determinó la dosis letal media aguda (DL50) por exposición tópica y oral de las formulaciones comerciales de los insecticidas con los ingredientes activos Imidacloprid, Spinosad y Thiocyclam hidrogenoxalato, ampliamente utilizados para el control de plagas de cultivos importantes en Colombia. Las pruebas DL50 se realizaron a partir de modificaciones de los lineamientos establecidos por la EPPO y OEDE para estas pruebas en Apis mellifera. Se evaluaron 5 dosis para cada insecticida y exposición. Se evaluaron 25 obreras de tamaño medio en cada dosis por duplicado. La mortalidad se registró a las 24, 48 y 72 horas después del experimento. Los datos fueron analizados con el modelo de regresión Probit. Para el Imidacloprid la DL50 tópica y oral fue de 0.048 µg/abeja y 0.010 µg/abeja respectivamente. Para el Thiocyclam hidrogenoxalato la DL50 tópica y oral fue de 0.244 µg/abeja y de 0.056 µg/abeja respectivamente. Para el Spinosad, la DL50 por exposición oral correspondió a 0.28 µg/abeja. No fue posible establecer la DL50 por exposición tópica. A partir del cálculo del Cociente de Riesgo (HQ) e Índice de Toxicidad Relativa, los tres ingredientes activos son altamente tóxicos. Se analiza y discute el riesgo debido al uso de los productos evaluados a partir de la naturaleza química de los insecticidas.
Abstract:The effect of insecticides on bees has gained great attention, however, there are few studies that explore this issue on Neotropical bees. Bombus atratus is a neotropical species broadly distributed in Colombia and is considered an important pollinator of both Andean ecosystems and agroecosystems. However, as for many wild bees species, the effect of insecticides on B. atratus is unknow. In this study we determined the acute median lethal dose (LD50) of commercial formulations of insecticides Imidacloprid, Spinosad and Thiocyclam hydrogen oxalate, widely used in Colombia to control several pests of important crops. The LD50 was carried out by oral and contact routes, following and modifying the EPPO and OECD guidelines to perform LD50 on A. mellifera. We evaluated five doses for each route and insecticide, in a total of 25 medium-size workers for each dose by duplicate. Mortality was registered at 24, 48 and 72 hours after the experiment; and data were analyzed with the Probit regression model. For Imidacloprid, contacts and oral LD50 were 0.048 µg/bee and 0.010 µg/bee, respectively. For Thiocyclam hydrogen oxalate, topical and oral LD50 were 0.244 µg/bee and 0.056 µg/bee, respectively. For Spinosad, the oral LD50 corresponded to 0.28 µg/bee; it was not possible to establish the LD50 for the contact route. The Hazard Quotient (HQ) and Index of Relative Toxicity indicated that all three active ingredients are highly toxic. We discussed the risk of the insecticides use on B. atratus, considering their chemical nature. Rev. Biol. Trop. 64 (4): 1737-1745. Epub 2016 December 01.
Subject(s)
Animals , Bees/drug effects , Macrolides/toxicity , Neonicotinoids/toxicity , Heterocyclic Compounds, 1-Ring/toxicity , Insecticides/toxicity , Nitro Compounds/toxicity , Reference Values , Time Factors , Risk Assessment , Drug Combinations , Lethal Dose 50ABSTRACT
Aims: To evaluate the antisickling and radical scavenging activities and acute toxicity of indigenous nutritive formula Drepanoalpha®, produced through a bio-guided based plant selection. Study Design: Drepanoalpha® extracts, Antisickling activity by Emmel test, Antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl bleaching methods; acute toxicity on rats, determination of biological and haematological parameters. Place and Duration of Study: Science Faculty University of Kinshasa, between January 2013 and February 2014. Methodology: The antisickling and antioxidant activities of Drepanoalpha® were determined using Emmel and the 1,1-diphenyl-2-picrylhydrazyl bleaching methods respectively. Acute oral toxicity test was performed to determine the LD50. Liver and kidney functions, the hematological and histopathological examinations were assessed using standard techniques. Results: Obtained results revealed that Drepanoalpha® possessesinteresting in vitro antisickling and antioxidant activities as revealed by the observed normal biconcave form of sickle erythrocyte (normalization rate >80%) and the radical scavenging activity (ED50= 0.604 ± 0.028 μg/mL). Acute toxicity assessment revealed that the medium lethal dose (LD50) is higher than 4000 mg/kg. Drepanoalpha® significantly increases the values of WBC, RBC, Hb, HCT, PLT, IDR-CV and PCT. Furthermore, this polyherbal formula significantly decreases the values of IDR-SD, P-RGC, AST and ALT (p<0.05). Both the control and treated groups displayed comparable non altered histological architecture of the liver cells. Discussion: The mean values of biochemical markers and hematological markers of treated rats revealed that Drépanoalpha® is potentially safe indicating non-toxic effect of the phytomedicine on immune cells and blood clotting factors. Moreover, this poly-herbal formulation increases the hemoglobin rate in the all treated rats (500-4000 mg/kg bodyweight) and preserves the histological architecture of the liver cells. Conclusion: Drepanoalpha® may increase weight gain, promote erythropoiesis and thrombopoeisis in sicklers patients. This phytomedicine could be used in the treatment of all form of anemia and may also prevent bile duct obstruction or intra-hepatic cholestasis. The results can form the basis for clinical trials in humans.
ABSTRACT
Phyllanthus tenellus Roxb. é nativa do Brasil, mais frequentemente em ambientes úmidos, e usada para o tratamento de litíase urinária, doença inflamatória intestinal, diabetes e hepatite B. Neste trabalho objetiva-se determinar a toxicidade aguda e DL50 do extrato aquoso de P. tenellus em animais de laboratório e avaliar o seu comportamento. A DL50 por via intraperitoneal foi calculada pelo método de Karber e Behrens (1964), em que o extrato alcoólico a 96% foi concentrado em evaporador rotativo. Utilizou-se camundongos albinos (Mus musculus) machos, divididos em 3 lotes de seis animais. Eles foram observados por 24 horas a partir da administração do extrato diluído em solução fisiológica a 0,9% nas dosagens de 500; 1000; 1500; 2000; 2500 mg/kg. Estudos de curto prazo têm demonstrado que esta planta não é considerada tóxica, porém, constatamos que esta espécie provoca agitação nos animais por movimentos estereotipados, espasmos, e um aumento da frequência respiratória, bem como ações de depressão, tais como: sonolência, prostração, dispneia e diminuição da frequência respiratória.
Phyllanthus tenellus Roxb. is a herbaceous plant native to Brazil and appears frequently in humid environments. This plant is used to treat urolithiasis, inflammatory bowel disease, diabetes and hepatitis B. The acute toxicity and LD50 of an aqueous extract of P. tenellus were determined in laboratory mice and their behavior was analyzed. The intraperitoneal LD50 was calculated by the Karber & Behrens (1964) method, for which a 96% alcoholic extract was concentrated in a rotary evaporator. Male albino mice (Mus musculus) were divided into three batches of six animals and observed for 24 hours after administration of the extract, diluted in 0.9% saline, at doses of 500, 1000, 1500, 2000 and 2500 mg / kg. Short-term studies have demonstrated this plant to be non-toxic; however, we found that this species induced agitation in animals, with stereotyped movements, spasms and increased respiratory frequency, as well as signs of depression, such as sleepiness, prostration, dyspnea and a reduction in respiratory frequency.
Subject(s)
Animals , Male , Mice , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Phyllanthus , MiceABSTRACT
Este trabalho teve como objetivo investigar a composição química, estabelecer a dose letal média (DL50) e avaliar os potenciais efeitos mutagênicos do extrato hidroalcoólico de folhas e inflorescências de Erythrina mulungu Mart. ex Benth por meio do teste de micronúcleo em medula óssea de camundongos. Os ensaios fitoquímicos foram realizados através de reações preliminares com mudança de coloração e/ou formação de precipitado; a DL50, por meio da administração intraperitoneal de três concentrações dos extratos, avaliando-se o número de óbitos após 48 horas e o teste de micronúcleo foi feito por meio do método do esfregaço, após exposição dos animais a cinco dias de tratamento. Os resultados fitoquímicos demonstraram presença de açúcares redutores, fenóis e taninos, proteínas e aminoácidos, flavonóides, alcalóides, depsídeos e depsidonas e derivados de cumarina em ambos os órgãos; saponinas espumídicas e esteróides e triterpenóides nas folhas e glicosídeos cardiotônicos e antraquinônicos e alcalóides nas inflorescências. Para a DL50 a folha demonstrou-se atóxica e a inflorescência moderadamente tóxica. Para o teste de micronúcleo, os resultados indicaram ausência de citotoxicidade e genotoxicidade dose-dependente para as folhas e independente da dose para as inflorescências. Assim, esses resultados sugerem que a planta, nas condições analisadas, possui potencial para induzir danos ao DNA.
This study aimed to investigate the chemical composition, to establish the mean lethal dose (LD50) and to assess the potential mutagenic effects of hydroalcoholic extract of leaves and inflorescences of Erythrina mulungu Mart. ex Benth by using micronucleus test in bone marrow of mice. Phytochemical assays were carried out through preliminary reactions with color change and/or precipitate formation; the LD50 was obtained by intraperitoneal administration of three concentrations of the extracts, assessing the number of deaths after 48 hours, and the micronucleus test was done by the smear method, after exposure of animals to five days of treatment. Phytochemical results showed the presence of reducing sugars, phenols and tannins, proteins and amino acids, flavonoids, alkaloids, depsides, depsidones and coumarin derivatives in both organs; foaming and steroidal saponins and triterpenes in the leaves and cardiotonic and anthraquinonic glycosides and alkaloids in the inflorescences. Considering the LD50, the leaf was atoxic and the inflorescence was moderately toxic. As regards the micronucleus test, results indicated absence of cytotoxicity while genotoxicity was dose-dependent for leaves and dose-independent for inflorescences. Thus, these results suggest that the plant, under the tested conditions, has the potential to induce damages to the DNA.
Subject(s)
Animals , Male , Female , Mice , Plant Leaves/metabolism , Erythrina/classification , Phytotherapy/instrumentation , Micronucleus Tests/instrumentation , Plant Leaves/chemistry , Lethal Dose 50ABSTRACT
In order to determine the lethal dose (96-h LD50) of the bacteria Aeromonas hydrophila to matrinxã, Brycon amazonicus, to be applied in challenge tests, 90 fish (63.23 ± 6.39 g) were divided into five treatments, with different bacterial solutions: T1 - Control (0.9 percent NaCl saline solution); T2 (4 x 10(11) cells/ mL); T3 (5 x 10(11) cells/ mL); T4 (1.36 x 10(12) cells/ mL) and T5 (3.06 x 10(12) cells/ mL). Fish were previously anesthetized with benzocaine (60 mg L-1), inoculated in the peritoneal cavity with the bacterial suspensions and then distributed into fifteen 80-L test chambers, where the water variables were monitored and fish mortality was observed. The experiment was randomly designed in three replicates and the 96-h LD50 was estimated according to the trimmed Spearman-Karber method. Water quality variables remained within adequate ranges for fish health and performance. Fish mortality rate increased with the bacterial concentrations of A. hydrophila (T1 = 0 percent; T2 = 16.66 percent; T3 = 44.44 percent; T4 = 72.22 percent and T5 = 100 percent), and the first mortalities were observed after 57 h, although the signs of the bacterial infection were already observed 24 h after the inoculation. The results indicate that the 96-h LD50 value of A. hydrophila to matrinxã is 6.66 x 10(11) cells/ mL.
Para determinar a dose letal (DL50 96-h) da bactéria Aeromonas hydrophila para o matrinxã, Brycon amazonicus, com aplicabilidade para testes de desafio, foram utilizados 90 peixes (63,23 ± 6,39 g), divididos em cinco tratamentos, com diferentes soluções bacterianas: T1 - Controle (solução salina 0,9 por cento NaCl); T2 (4 x 10(11) células/ mL); T3 (5 x 10(11) células/ mL-1); T4 (1,36 x 10(12) células/mL-1) e T5 (3,06 x 10(12) células/ mL-1). Os peixes foram previamente anestesiados com benzocaína (60 mg L-1), inoculados na cavidade peritoneal com as suspensões bacterianas e distribuídos em 15 aquários de vidro de 80 L de capacidade, com aeração constante. O experimento teve duração de 96 h, no qual foram monitoradas a mortalidade e a qualidade da água. O delineamento experimental foi inteiramente casualisado com três réplicas e a DL50 96-h foi estimada de acordo com o método Spearman-Karber. Durante o experimento os parâmetros físico-químicos da água permaneceram dentro das condições consideradas adequadas para o desenvolvimento e saúde dos organismos aquáticos. A mortalidade dos peixes aumentou nas concentrações crescentes de A. hydrophila (T1 = 0 por cento; T2 = 16,66 por cento; T3 = 44,44 por cento; T4 = 72,22 por cento e T5 = 100 por cento), contudo, as primeiras mortalidades ocorreram em 57 h após a inoculação das concentrações bacterianas, sendo observados os primeiros sinais de infecção em 24 h após a inoculação. Os resultados indicam que o valor da DL50 96-h da bactéria A. hydrophila para o matrinxã foi igual a 6,66 x 10(11) células/mL de solução salina.
Subject(s)
Animals , Aeromonas hydrophila , FishesABSTRACT
Acute toxicity test (LD-50) using toxic shock syndrome toxin (TSST-1) was tested in BALB/c, C57BL/6 and Swiss mice. Animals (n = 10) were intraperitoneally injected with TSST-1 (0.01-10.0µg/mouse) followed 4h later by potentiating dose of lipopolysaccharide (75.0µg of LPS - E. coli O111:B4) and cumulative mortality was recorded over 72h. Control animals received either TSST-1 or LPS alone. The data were submitted to qui-Square test and acute toxicity test was calculated by probit analysis (confidence limits expressed as µg toxin/kg). BALB/c mice was the most sensitive (20.0µg/kg, 95 percent confidence limits: 9.0-92.0) followed by C57BL/6 (38.5µg/kg, 95 percent confidence limits: 9.11- 401.6). Data from Swiss mice was not conclusive, indicating only low sensitivity. Selection of the animal model and standardization of the experiment are fundamental for the development of serum neutralization tests used for final quality control of vaccine production.
A toxicidade aguda (DL-50) da toxina da síndrome do choque tóxico (TSST-1) foi testada em linhagens de camundongos BALB/c, C57BL/6 e Suíça. Os animais (n=10) inoculados intraperitoneal com doses crescentes de toxina (0,01 - 10,0µg/animal) receberam 4h após 75µg de LPS (E. coli O111: B4). A toxicidade aguda (DL50) foi observada por um período de 72h e os dados submetidos ao teste de qui- quadrado. Os resultados e os limites de confiança foram expressos em µg de toxina/kg. A linhagem BALB/c apresentou maior sensibilidade (20µg/kg - limite de confiança a 95 por cento entre 9,0- 92,0), seguida da C57BL/6 (38,5µg/kg - limite de confiança a 95 por cento entre 9,11 - 401,6). A amplitude dos limites de confiança deve-se à natureza da toxina, ao mecanismo de ação, a via de inoculação e ao animal utilizado. A seleção do modelo animal e a padronização do experimento são fundamentais para o desenvolvimento de testes de soro neutralização para fins de controle de qualidade do processo de produção de vacinas.