Zebrafish is a frequently employed model organism in systems medicine and biomarker discovery. A crosscutting fundamental question, and one that has been overlooked in the field, is the "system... Show moreZebrafish is a frequently employed model organism in systems medicine and biomarker discovery. A crosscutting fundamental question, and one that has been overlooked in the field, is the "system-wide" (omics) effects induced in zebrafish by metabolic solvents and culture buffers. Indeed, any bioactivity or toxicity test requires that the target compounds are dissolved in an appropriate nonpolar solvent or aqueous media. It is important to know whether the solvent or the buffer itself has an effect on the zebrafish model organism. We evaluated the effects of two organic carrier solvents used in research with zebrafish, as well as in drug screening: dimethyl sulfoxide (DMSO) and ethanol, and two commonly used aqueous buffers (egg water and Hank's balanced salt solution). The effects of three concentrations (0.01, 0.1, and 1%) of DMSO and ethanol were tested in the 5-day-old zebrafish embryo using proton nuclear magnetic resonance ((1)H NMR) based metabolomics. DMSO (1% and 0.1%, but not 0.01%) exposure significantly decreased the levels of adenosine triphosphate (ATP), betaine, alanine, histidine, lactate, acetate, and creatine (p < 0.05). By contrast, ethanol exposure did not alter the embryos' metabolome at any concentration tested. The two different aqueous media noted above impacted the zebrafish embryo metabolome as evidenced by changes in valine, alanine, lactate, acetate, betaine, glycine, glutamate, adenosine triphosphate, and histidine. These results show that DMSO has greater effects on the embryo metabolome than ethanol, and thus is used with caution as a carrier solvent in zebrafish biomarker research and oral medicine. Moreover, the DMSO concentration should not be higher than 0.01%. Careful attention is also warranted for the use of the buffers egg water and Hank's balanced salt solution in zebrafish. In conclusion, as zebrafish is widely used as a model organism in life sciences, metabolome changes induced by solvents and culture buffers warrant further attention for robust systems science, and precision biomarkers that will stand the test of time. Show less
Cannabinoids are a group of terpenophenolic compounds and are naturally found in the cannabis plant (Cannabis sativa L). _9-Tetrahydrocannabinol (_9-THC) is the psychoactive cannabinoid. The high... Show moreCannabinoids are a group of terpenophenolic compounds and are naturally found in the cannabis plant (Cannabis sativa L). _9-Tetrahydrocannabinol (_9-THC) is the psychoactive cannabinoid. The high lipophilicity of _9-THC is a hindering factor in the further development of this compound into a large scale pharmaceutical product. In an effort to generate highly polar derivatives of _9-THC, we screened 206 alkane degrading bacterial strains. In total, eight derivatives were produced on milligram. All of these biotransformation products harbored modified alkyl chains, with hydroxy, carboxy and ester functionalities. We also investigated the potential of cell suspension culture of Catharanthus Roseus to transform _9-THC. Unlike bacterial strains, Catharanthus Roseus cells transformed _9-THC to its glycosylated and additionally hydroxylated derivatives. The behavioral effects of __9-THC are mediated by the centra l CB1 receptor in rats. CB1 receptors show high degree of sequence conservation in vertebrates. We used zebrafish embryos as a model to study the behavioral effects of cannabinoids. We conclude that cannabinoids have behavioural effects in zebrafish that are comparable to some of those reported in the literature for mammals. In particular, the acute exposure response resembles behavioural effects reported for adult. This suggests that some similarity in cannabinoid response pathways between zebrafish and mammals exists. We also performed the metabolomic profiling of zebrafish embryos treated with the concentrations of CB1 agonist and antagonist used in behavioural assays. The results of behavioural assays were successfully correlated with the metabolomic data of zebrafish embryos. Show less
