Neurodegeneration of CNS by ingestion of I. carnea in guinea pigs

CHOLICH, L; MARQUEZ, M; PUMAROLA, M; GIMENO, E.J.; TEIBLER, P.G.; RIOS E; GARCÍA ENRIQUE N; ACOSTA DE PEREZ, .O.C.

Sao Paulo

Simposio; 4th Symposium of the Latin American Society of Toxicologic Pathology; 2012

Facultade de Medicina Veterinária e Zootecnia

Ipomoea carnea is a toxic plant, able to generate a poisoning in goats. It is characterized by nervous disorders and death. Swainsonine and calystegines B1, B2 and C1 were the isolated toxic principles from I. carnea. A naturally occurring guinea pig model of this disease has a similar clinical presentation to human inherited α-mannosidosis. The aim of this study was to perform a detailed analysis the CNS of guinea pigs intoxicated with I. carnea, and to compare with inherited α-mannosidosis in guinea pigs. Leaves of Ipomoea were administered to guinea pigs during 65 days. The brains of all animals were removed and sections were stained with PAS and KB. IHC was done using paraffin-embedded 5 µm sections for detection of ubiquitin, glial fibrillary acidic protein and microglia. The kit EnVision (DakoCytomation) was used as detection system.Throughout the brain vacuoles were observed in the perikarion of neurons. Vacuoles were PAS- negative and the Nissl substance was dispersed or absent. This finding was confirmed using KB stain. Besides, not differences in intensity of myelin staining with KB were observed between affected and control groups Iba-1 IHC showed hypertrophic microgliosis in affected animals. Additionally, in the medulla oblongata of affected animals, numerous ubiquitin positive spheroids, together with neuronal degeneration, were observed in the nucleus gracile and also, but in less extent, the cuneate one. Our results indicate that I. carnea ingestion in guinea pig induced neurodegeneration by abundant vacuoles, mainly in brainstem. These were negatives by KB and PAS staining. Besides, spheroids were observed in medulla oblongata. These findings are in part similar to those found in guinea pig with genetic α- mannosidosis. Our results suggest that this is a good model for the study of human inherited α-mannosidosis.