Improved method for diagnosis of Nerium oleander poisoning in necropsy tissues / Método aprimorado para diagnóstico da intoxicação por Nerium oleander em tecidos de necropsia

Nerium oleander is an ornamental cardiotoxic plant found in tropical and subtropical areas of the World. Its toxicity is related to the content of cardioactive glycosides, mainly oleandrin, found throughout the plant. The present study aimed to describe a new and improved method for oleandrin detection in tissue samples. The determination of oleandrin was made after extraction with a modified QuEChERS technique and measurement by UFLC-MS/MS. A total of 36 guinea pigs (Cavia porcellus) were distributed into 3 groups (n=12): control group that received only water orally (CON), and two treated groups that received hydroalcoholic oleander extract at doses of 150mg.kg-1 (OLE 150) and 300mg.kg-1 (OLE 300) in single oral dose. After three hours, fragments of heart, kidneys, liver and brain were collected for determination of oleandrin levels. The extraction and chromatographic procedures were effective for oleandrin detection and quantification in tissues, with retention time of 1.2 min and detection limit of 0.001μg g-1. The chromatographic analysis of treated guinea pigs indicated that oleandrin is distributed equally among the analyzed tissues. The developed methodology is a reliable, effective and rapid form of diagnosis of N. oleander poisoning based on necropsy tissue samples.(AU)

Nerium oleander é uma planta cardiotóxica ornamental encontrada em áreas tropicais e subtropicais do mundo. Sua toxicidade é relacionada á presença de glicosídeos cardioativos, principalmente a oleandrina, encontrada em toda a planta. O presente estudo objetiva descrever um novo e aprimorado método para detecção da oleandrina em amostras de tecido. A determinação da oleandrina foi feita após extração utilizando técnica modificada de QuEChERS e mensuração por UFLC-MS/MS. Um total de 36 cobaios (Cavia porcellus) foi distribuído em três grupos (n=12): grupo controle que recebeu apenas água por via oral (CON), e dois grupos tratados que receberam extrato hidroalcóolico de oleander nas doses de 150mg.kg-1 (OLE 150) e 300mg.kg-1 (OLE 300) em uma única dose oral. Após três horas, fragmentos do coração, rins, fígado e cérebro foram coletados para determinação dos níveis de oleandrina. A extração e procedimentos cromatográficos foram eficientes na detecção e quantificação da oleandrina nos tecidos, com tempo de retenção de 1,2min e limite de detecção de 0,001μg g-1. A análise cromatográfica dos animais tratados indicou que a oleandrina é distribuída de forma equalizada pelos tecidos analisados. A metodologia desenvolvida representa uma forma de diagnóstica segura, efetiva e rápida da intoxicação por N. oleander a partir de amostras de tecidos de necropsia.(AU)

Molluscicidal and physiological activities of some plants against biomphalaria Alexandria snails

The molluscicidal activity of three plants: Nerium oleander, Dizygotheca elegantissima and A gave decipiens on Biomphalaria Alexandrina snails at different exposure intervals and size or age of snails was studied throughout the present investigation. Also, the effects of these selected plants on Schistosoma mansoni cercariae and miracidia were assessed. Moreover, the role of sublethal concentrations of these plants on physiological processes and functions on the hemolymph of these snails was also clarified. Results showed that N. oleander proved the most effective plant as its LC[90] was 100ppm after 24hrs from exposure compared with the values of 120 and 180 ppm with the plants D. elegantissima and A. decipiens, respectively. The elongation of remarkable exposure periods from 24 to 48 hrs increased the molluscicidal activities of the tested plants. Different sizes or ages of Biomphalaria Alexandrina snails showed different susceptibility levels towards the action of the tested plants. Newly hatched snails were the most sensitive group. When the LC[50] and LC[90] of the experimental plants were tested against the cercariae, almost 100% of cercarial mortality was obtained after only two hrs when used 100, 120 and180 ppm for Nerium oleander, Dizygotheca elegantissima and Agave decipiens, respectively. Meanwhile, 100% miracidia mortality was obtained after 1 hr when exposed to the same concentrations. Thus miracidia proved more susceptible than cercariae. While used the sublethal concentrations of these plants, the LC[0] of the three tested plants showed moderate significant increase in transaminases activities. The total protein, albumin and globulin were slightly changed; while the A/G ratio did not record any changes between treated and control snails. The application of plant molluseicides resulted in marked increase of total lipid content; the maximal observation was recorded with the use of both N. oleander, and D. elegantissima