HTS compatible assay for antioxidative agents using primary cultured hepatocytes

We have used primary cultured rat hepatocytes to establish a system that is compatible with HTS for screening substance libraries for biologically active compounds. The hepatocytes were treated with t-BHP to induce oxidative stress, leading to the formation ROS. The involvement of ROS in oxidative stress and pathological alterations has been of major interest in recent years, and there is great demand to identify new compounds with antioxidant potential. In most HTS programs each compound is tested in duplicate, and may only be tested once. Because of this it is important to develop assays that can identify candidate compounds accurately and with high confidence. Using newly available cell-based assay systems, we have developed a system that can detect active compounds (hits) with a high degree of confidence. As an example of an agent that can be detected from a substance library, we analyzed the effect of fisetin as an antioxidative compound using this system. All measurements were performed using the newly developed and highly versatile Multilabel-Reader Mithras LB 940 (Berthold Technologies, Bad Wildbad, Germany). The data presented show that all Z' factors determined were highly reliable. Although the protocol is primarily designed to screen for substances with antioxidative potential, it can easily be adapted to screen for other biologically active substances.