Behavioral effects of a neurotoxic compound isolated from Clibadium surinamense L (Asteraceae)

Behavioral, electrocorticographic and electrocardiologic changes in Colossoma macropomum (Tambaqui) in the effect of cunaniol

The Clibadium spp. is a shrub of occurrence in the Amazon, popularly known as Cunambi. The compounds in the leaves demonstrate ichthyotoxic properties, and its major substance, cunaniol, is a powerful central nervous system stimulant with proconvulsant activity. Few current studies relate behavioral changes to the electrophysiological profile of fish poisoning. This study aimed to describe the behavioral, electromyographic, electroencephalographic, electrocardiographic, and seizure control characteristics of anticonvulsant drugs in Colossoma macropomum submitted to cunaniol intoxication during bathing containing 0.3 μg/L cunaniol. The behavioral test showed rapid evolution presenting excitability and spasms, which were confirmed by the analysis of Electroencephalogram (EEG), Electromyogram (EMG), and changes in cardiac function detected in the ECG. Cunaniol-induced excitability control was evaluated using three anticonvulsant agents: Phenytoin, Phenobarbital, and Diazepam. While phenytoin was not effective in seizure control, diazepam proved to be the most efficient. These results demonstrate the susceptibility of Colossoma macropomum to cunaniol poisoning, given that the central nervous system and electrocardiographic changes were considered severe.

Cunaniol-elicited seizures: Behavior characterization and electroencephalographic analyses

This study aimed at describing the characteristics and properties of seizures induced by cunaniol, a polyacetylenic alcohol isolated from the Clibadium genus, which is ubiquitous in the Amazon biodiversity and its potential use as a convulsant model. Wistar rat behavior was assessed upon cunaniol administration and animals were evaluated for neural activity through electroencephalographic records whereby epidural electrodes were positioned over the motor cortex under cunaniol-elicited seizures and seizure's control using three anticonvulsant agents, namely phenytoin, phenobarbital and diazepam. Cunaniol-induced seizures displayed a cyclic development of electrocorticographic seizures, presenting interictal-like spike and ictal period, which correlates to the behavioral observations and is in line with acute seizures induced by pentylenetetrazole. Cunaniol-elicited seizures were intractable by phenytoin treatment and controlled under the GABAergic activities of phenobarbital and diazepam. The results indicate that the cunaniol-induced changes show characteristics of seizure activity, making this plant compound a suitable animal convulsant model for seizure-related studies that could be used to assist in the development of novel anticonvulsant agents.

Indução anestésica do extrato aquoso de cunambí, Clibadium surinamense linn para a realização de biometrias em tambaquis, Colossoma macropomum

RESUMO A biometria é uma etapa importante do processo de manejo realizada em peixes durante o cultivo. Porem essa pratica expõe os peixes a elevados níveis de estresses que podem ocasionar a debilidade ou ate mesmo a mortalidade dos peixes. O uso de anestésicos naturais como o cunambi, Clibadium surinamense é uma alternativa para minimizar os danos provocados pelo manuseio durante a biometria. O objetivo deste trabalho foi avaliar o cunambí como anestésico para juvenis de tambaqui. Para tanto, foram utilizadas três concentrações de extrato aquoso da planta (0,5, 1,5 e 2,5ml/L). Foram expostos individualmente 3 peixes (17,24g ± 14,01 e 9,18 ± 0,91cm) para cada tratamento e observados o tempo de indução e recuperação anestésica. O tratamento de 0,5ml/L necessitou de maior tempo para atingir o estágio de indução desejado de sedação profunda (7,4 minutos), contudo houve diferença significativa em relação às concentrações de 1,5 e 2,5ml/L. A concentração de 0,5 ml/L é a ideal para o procedimento de biometria e breve manejo, pois apesar da demora em induzir o peixe aos diferentes estágios de anestesia, provoca uma rápida recuperação (8,62 minutos) em relação a outros tratamentos 1,5ml/L (16,6 minutos) e 2,5 ml/L (23,7min).

Ta'ta', Huayani: perception of leishmaniasis and evaluation of medicinal plants used by the Chayahuita in Peru. Part II

AIM OF THE STUDY

A knowledge attitude and practice study centred on leishmaniasis and its treatment was performed among the Chayahuita, an Amazonian Peruvian ethnic group living in an endemic area. This study documents traditional Chayahuita plant's use and disease concepts. Also, activity of some medicinal plants used by the Chayahuita is highlighted and discussed.

MATERIALS AND METHODS

Ninety-three Chayahuita people were interviewed, following a semi-structured questionnaire focussed on disease knowledge and perception, personal attitude and healing practices. Simultaneously, a collection of plants was performed in different ecotopes, in order to make an extensive inventory of the pharmacopoeia.

RESULTS

For the Chayahuita, cutaneous (CL) and muco-cutaneous leishmaniasis (MCL) are considered as diseases of their own, with specific names, aetiologies, mode of transmission. Regarding CL, Chayahuita people consider that the humid characteristic of the skin ulcer is a discriminative fact orienting the diagnostic forTa'ta' (leishmaniasis). Forty-six different species were designated useful against LC and /or MCL (29 species by means of the questionnaire and 27 species when collecting in different ecotopes). Thirty-seven extracts corresponding to 31 species used medicinally were screened in vitro against Leishmania amazonensis axenic amastigotes, assessing their viability by the reduction of tetrazolium salt (MTT). Six species displayed a good activity (10 microg/ml<IC50<20 microg/ml): an undetermined hemi-epiphytic Clusiaceae, Cybianthus anthuriophyllus Pipoly (Myrsinaceae), two Piper, Piper sanguineispicum Trel., and Piper loretoanum Trel. (Piperaceae), Desmodium axillare Sw. DC. (Fabaceae), and Clibadium sylvestre (Aubl.) Baill. (Asteraceae).

CONCLUSION

Perception of leishmaniasis, attitude, treatments and diet prohibitions still largely reflects traditional Chayahuita cosmovision, even if some tentative of bio-medical re-interpretation is arising.