dicumarol and Weight-Loss

Drosophila diaphorase-1 (DIA-1) is an enzyme similar to mammalian DT-diaphorase and is inhibited in vitro by dicoumarol. However, a ten-fold increase in DIA-1 activity was observed when third instar Drosophila virilis larvae were fed on a diet containing 0.1 M dicoumarol for 48 h. This induction was shown to be dose dependent and immunoprecipitation experiments with DIA-1 anti-serum demonstrated an increase in the DIA-1 protein level in dicoumarol-treated larvae. The induction of DIA1 by dicoumarol was found to be blocked by actinomycin D, which suggests a transcriptional mechanism of regulation. The opposite effect of dicoumarol on DIA-1 in vitro vs. in vivo suggests that a metabolic conversion takes place after the ingestion of this compound by D. virilis larvae.

Topics: Animals; Dactinomycin; Dicumarol; Drosophila; Electrophoresis, Starch Gel; Enzyme Induction; Larva; NAD(P)H Dehydrogenase (Quinone); Weight Loss