Pyriproxyfen (S-31183) is an insecticide that acts as a biomimetic of juvenile hormone.

AChE:92.5 μmol/L(Zebrafish brain)

Zebrafish male adults were acutely exposed to 0.001, 0.01 and 0.1 μg/mL pyriproxyfen for 16 h. Mitochondrial respiration of brain tissues was assessed. ROS generation was estimated using H2DCF-DA and MitoSOX. Calcium transport was monitored by Calcium Green 5 N. NO synthesis activity was estimated using DAF-FM-DA. Brain acetylcholinesterase showed an in vivo IC20 of 0.30 μmol/L pyriproxyfen, and an IC50 of 92.5 μmol/L. The inhibitory effect on zbAChE activity was competitive-like. Respiratory control of Complex I/II decreased significantly after insecticide exposure. The MitoSOX test showed that O2- generation had a pyriproxyfen dose-dependent effect. Brain tissue lost 50% of Ca2+ uptake capacity at 0.1 μg/mL pyriproxyfen. Ca2+ release showed a clear mitochondrial impairment at lower pyriproxyfen exposures[1].