Pharmacological studies of C. elegans cultured in axenic media: nicotine and its effects on growth, body morphology, and reproduction

Abstract

C. elegans is a soil nematode that has been used as a model organism for pharmaceutical and environmental adaptation studies for decades. The primary culture method for raising C. elegans is to use bacterial Escherichia coli media plates. Using bacterial media can be resource intensive, result in turbidity for microscopy based assays, and bacterial metabolism can affect any pharmaceuticals introduced to the system. Liquid axenic media is chemically synthetic, optically transparent, and can be utilized in automated microfluidic devices and closed systems. However, there has been no quantification of changes in morphology, development, reproductive fitness, or lifespan as a result of adaptation to liquid axenic media. The WormSlide microfluidic device was developed and used with high temporal resolution automated microscopy to quantify the morphological changes, growth rates, reproductive behavior, and lifespan in liquid axenic C. elegans Habitation and Reproduction (CeHR) media. The media was also used to quantify certain phenotypic effects brought about by teratogenic nicotine exposure at various concentrations. This was used as a proof of concept that axenic media can be used as an alternative for pharmaceutical assays on C. elegans and that the baseline data acquired for CeHR will enable more laboratories to make effective use of the media.