PROBIEN   20416
INSTITUTO DE INVESTIGACION Y DESARROLLO EN INGENIERIA DE PROCESOS, BIOTECNOLOGIA Y ENERGIAS ALTERNATIVAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Non-conventional biomarkers of effects for organophosphates as alternatives in an experimental model showing inherently low-levels of acetylcholinesterase
Autor/es:
SOTOMAYOR V; VENTURINO A
Lugar:
Buenos Aires
Reunión:
Congreso; IV Congreso Argentino de la Sociedad de Toxicología y Química Ambiental, SETAC Argentina; 2012
Institución organizadora:
SETAC Argentina
Resumen:
This study documents alternatives to acetylcholinesterase
(AChE) as biomarkers of organophosphorus (OP) toxicity, in early stages of Rhinella. arenarum embryos which lack of
substantial activity of this enzyme until later in the development. Embryos
were exposed to sublethal concentrations (2-16 mg/l) of chlorpyrifos (CPF).
AChE activity, polyamine levels and their key regulator enzyme ornithine
decarboxylase (ODC), as well as transcription factors and signaling kinases
related to development were measured. AChE was induced by low CPF
concentrations, and inhibited only at 16 mg/l. Polyamine levels were diminished
at low concentrations, as well as ODC activity. Using western blot and
electromobility shift assay we studied transcription factor activator protein-1
(AP-1) pathway in our search of molecular effects in the absence of AChE
activity inhibition when embryos were exposed at low CPF concentrations. AP-1
binding to its consensus sequence in DNA (CRE) and the levels of its
constituent protein c-fos were decreased by CPF; c-fos activator kinase Erk-2
was also decreased. These results allow us to infer a possible pathway for CPF
effects in early toad embryos, leading to alteration in the polyamine
metabolism, since ODC transcription is under AP-1 regulation. We propose
polyamine levels, ODC activity and some members of the AP-1 pathway, as
alternative biomarkers of effects in R. arenarum
embryos at tail bud stage showing low levels of AChE activity hence lacking of
the classical response to OP.
Trabajo financiado por PICT 214-07 y PROIN U.N.Comahue
I-004