<abstract xmlns="http://www.w3.org/1999/xhtml"><p>This study examined the potential to minimize the cytotoxic or genotoxic effects that dimethylsulfoxide (DMSO), when used as solvent, has on the <italic>in vitro</italic> interleukin-8 (IL-8) release, mammalian cell cytotoxicity and micronuclei formation, and bacterial mutagenesis induced by cigarette smoke wet total particulate matter (WTPM). The use of DMSO as a solvent vehicle for test articles of limited water solubility is widely applied in <italic>in vitro</italic> assays due to its moderate toxicity to test organisms and its excellent solvent properties for both polar and non-polar compounds, such as WTPM. A significant DMSO dose-dependent depletion in the IL-8 release was observed, with or without the addition of WTPM, at concentrations spanning those typically employed in <italic>in vitro</italic> assays. DMSO at 3.6% reduced cell viability 40-50%. Overall, DMSO at final concentrations of 0.5% and 4.0% resulted in about 50% and 90% depletion of final IL-8 levels, respectively. DMSO-induced cytotoxicity was evident only at concentrations of 1.5% or more, a concentration higher than that typically employed in such testing. The WTPM-induced cytotoxicity was equivalent at low ranges of DMSO concentrations. DMSO concentrations of 3.6% or higher resulted in an increase of cytotoxicity by 20-25%. DMSO alone did not give rise to bacterial mutagenicity at doses from 0% to 3.9%; however, WTPM exposure with increasing levels of DMSO resulted in increased toxicity of the WTPM at doses of DMSO greater than 6.9%, as indicated by lower revertant counts. This effect suggests that for Ames assay analysis of WTPM collected in DMSO, the level of DMSO should be minimized to prevent lower revertant counts due to DMSO-induced toxicity. DMSO alone gave a dose-dependent increase in the background micronuclei percentage, with a statistically significant increase at 4%. In the presence of WTPM, DMSO at 3% concentration resulted in a significantly higher micro-nucleus frequency, suggesting a possible clastogenic role of DMSO or potential cell permeability differences. In conclusion, this study should provide guidance for the range of DMSO concentrations when used as a solvent for WTPM-mediated <italic>in vitro</italic> toxicological assays and therefore help in properly designing and conducting <italic>in vitro</italic> studies that utilize DMSO as the extraction solvent of choice.</p></abstract>

This study examined the potential to minimize the cytotoxic or genotoxic effects that dimethylsulfoxide (DMSO), when used as solvent, has on the in vitro interleukin-8 (IL-8) release, mammalian cell cytotoxicity and micronuclei formation, and bacterial mutagenesis induced by cigarette smoke wet total particulate matter (WTPM). The use of DMSO as a solvent vehicle for test articles of limited water solubility is widely applied in in vitro assays due to its moderate toxicity to test organisms and its excellent solvent properties for both polar and non-polar compounds, such as WTPM. A significant DMSO dose-dependent depletion in the IL-8 release was observed, with or without the addition of WTPM, at concentrations spanning those typically employed in in vitro assays. DMSO at 3.6% reduced cell viability 40-50%. Overall, DMSO at final concentrations of 0.5% and 4.0% resulted in about 50% and 90% depletion of final IL-8 levels, respectively. DMSO-induced cytotoxicity was evident only at concentrations of 1.5% or more, a concentration higher than that typically employed in such testing. The WTPM-induced cytotoxicity was equivalent at low ranges of DMSO concentrations. DMSO concentrations of 3.6% or higher resulted in an increase of cytotoxicity by 20-25%. DMSO alone did not give rise to bacterial mutagenicity at doses from 0% to 3.9%; however, WTPM exposure with increasing levels of DMSO resulted in increased toxicity of the WTPM at doses of DMSO greater than 6.9%, as indicated by lower revertant counts. This effect suggests that for Ames assay analysis of WTPM collected in DMSO, the level of DMSO should be minimized to prevent lower revertant counts due to DMSO-induced toxicity. DMSO alone gave a dose-dependent increase in the background micronuclei percentage, with a statistically significant increase at 4%. In the presence of WTPM, DMSO at 3% concentration resulted in a significantly higher micro-nucleus frequency, suggesting a possible clastogenic role of DMSO or potential cell permeability differences. In conclusion, this study should provide guidance for the range of DMSO concentrations when used as a solvent for WTPM-mediated in vitro toxicological assays and therefore help in properly designing and conducting in vitro studies that utilize DMSO as the extraction solvent of choice.

<italic>In Vitro</italic> Toxicological Evaluation of Cigarette Smoke Particulate Matter: Effect of Dimethyl Sulfoxide (DMSO) as Solvent

AW Spears Research Center, Lorillard Tobacco Company, 420 N. English Street, Greensboro, NC 27420

Current address: ICCVAM/NICEATM, Integrated Laboratory Systems, Inc., P.O. Box 13501, Research Triangle Park, NC 27709.

Contributions to Tobacco & Nicotine Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

 Toxicological Evaluation of Cigarette Smoke Particulate Matter: Effect of Dimethyl Sulfoxide (DMSO) as Solvent

This study examined the potential to minimize the cytotoxic or genotoxic effects that dimethylsulfoxide (DMSO), when used as solvent, has on the in vitro...

In Vitro Toxicological Evaluation of Cigarette Smoke Particulate Matter: Effect of Dimethyl Sulfoxide (DMSO) as Solvent

Published Online: Dec 30, 2014

Page range: 2 - 9

Received: Oct 26, 2008

Accepted: Oct 26, 2009

DOI: https://doi.org/10.2478/cttr-2013-0875

© 2010 Beiträge zur Tabakforschung International

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.