PgmNr D1233: Developmental Toxicity Testing of Cigarette Smoke and E-Cigarette Vapor Using Drosophila melanogaster Primary Embryonic Stem Cell Cultures.

Authors:
T. M. Ubina; J. Juarez; M. Gallardo; J. Pilotin; N. Bournias-Vardiabasis


Institutes
California State University, San Bernardino, San Bernardino, CA.


Keyword: other ( Developmental toxicity screening )

Abstract:

E-cigarettes (EC) are relatively new and many of the effects they have on the body are still unknown. Given this, even less is known about the effects they have on embryonic development. Previously identified as a reliable method for teratogen testing, Drosophila melanogaster embryos fully develop and hatch into larvae 24 hours after oviposition which makes them attractive as a fast and reliable method of testing developmental toxicants (Bournias-Vardiabasis, 1983). When primary cultures are taken at the gastrula stage of development, the embryonic stem cells will differentiate into the beginnings of the muscular and neuronal systems in vitro within 24 hours and these differentiated cells, called myotubes (MT) and neuronal clusters (NC), can be observed and quantified. In this study, primary cultures of wild type D. melanogaster embryos were homogenized and cultured at the gastrula stage and were then exposed to conventional and e-cigarette vapors dissolved into culture media at various concentrations. From conventional cigarettes, mainstream smoke (MS) and sidestream smoke (SS) were both tested. MS smoke is the smoke that the smoker actively inhales and SS smoke is what comes from the burning end of the cigarette and is what we commonly think of as second-hand smoke. The smoke concentrations were measured in Puff Equivalents (PE) which is the amount of smoke from 1 puff of a cigarette that will dissolve into 1 mL of solution. SS smoke, MS smoke were tested at 1.0 PE/mL, 0.1 PE/mL and 0.01PE/mL. EC vapor was tested at 0.1 PE/mL and 0.01 PE/mL. The numbers of neuronal clusters and myotubes were counted 24 hours after exposure and a Student’s t-test was performed. If the cell counts of either NCs or MTs were reduced enough to be deemed significant by the t-test, the solution was labeled as a developmental toxicant. MS smoke was toxic at 1.0 and 0.1 PE/ml, SS was toxic at all concentrations, EC vapor was toxic at 0.1PE/mL.