Natural Products as Potential Human Ether-A-Go-Go-Related Gene Channel Inhibitors - Screening of Plant-Derived Alkaloids
Abstract
Inhibition of the cardiac human ether-a-go-go-related gene channel is a problematic off-target pharmacological activity and, hence, a major safety liability in clinical practice. Several non-cardiac drugs have been restricted in their use, or even removed from the market due to this potentially fatal adverse effect.
Comparatively little is known about the human ether-a-go-go-related gene inhibitory potential of plant-derived compounds. In the course of an ongoing human ether-a-go-go-related gene in vitro study, a total of 32 structurally diverse alkaloids of plant origin as well as two semi-synthetically obtained protoberberine derivatives were screened by means of an automated Xenopus oocyte assay.
Protopine, (+)-bulbocapnine, (+)-N-methyllaurotetanine, (+)-boldine, (+)-chelidonine, (+)-corynoline, reserpine, and yohimbine reduced the human ether-a-go-go-related gene current by }= 50% at 100 mu M, and were submitted to concentration-response experiments. Our data show that some widely occurring plant-derived alkaloids carry a potential risk for human ether-a-go-go-related gene toxicity.