Systems Toxicology

Ahmed Ghallab1[*]

1Forensic Medicine and Toxicology Department, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt

EXCLI J 2015;14:Doc1267


In recent years system-level understanding has become a cutting edge topic in toxicology (Geenen et al., 2012[11]; Marchan et al., 2012[22]; Widom et al., 2014[31]; Kell, 2010[20]). Recently, a definition of Systems Toxicology has been suggested: “Systems Toxicology is the integration of classical toxicology with quantitative analysis of large networks of molecular and functional charges occurring across multiple levels of biological organization” (Sturla et al., 2014[27]). Although this definition has been published by outstanding scientists in this field of research it leaves some questions open. Is “analysis of large networks” really an essential requirement of Systems Toxicology? It is out of question that understanding the interactions of different levels of biological organization is of high interest. However, is the analysis of “charges occurring across multiple levels of biological organization” another indispensible necessity of Systems Toxicology? And how is “classical toxicology” integrated “with quantitative analysis of large networks”? Does not already “classical toxicology” use quantitative methods and e. g. network analysis? I will stop here torturing the reader with further questions. The point I wish to make is that I feel sometimes a bit defeated by the awesome but not fully clear sentences in this field of research. Important, in my opinion, is whether Systems Toxicology leads to answers of questions that are otherwise difficult to obtain. This will be illustrated by three examples:

Understanding the mechanisms of organ toxicity has always been a major goal in toxicology (Campos et al., 2014[3]; Hammad, 2014[17]; Godoy et al., 2015[16], 2013[15], 2012[13], 2009[14]; Dias da Silva et al., 2013[4]; Driessen et al., 2013[9]; Shimada et al., 2012[26]; Baulies et al., 2015[2]; Reif, 2014[23][24]). In many circumstances Systems Toxicology techniques may help to gain a deeper understanding, particularly in situations where several mechanisms interact and due to high complexity the situation is difficult to understand intuitively (Widera et al., 2014[30]; Friebel et al., 2015[10]; Bartl et al., 2015[1]). Nevertheless, it is important that clear hypotheses are addressed by the simulations and that model predictions can be confirmed or rejected experimentally.



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[*] Corresponding Author:

Ahmed Ghallab, Forensic Medicine and Toxicology Department, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt, eMail: ghallab@vet.svu.edu.eg