ILSI Health and Environmental Sciences Institute (HESI), global leader in advancing translational science to create science-based solutions for a sustainable, healthier world

QSAR/QSPR models based on quantum chemistry for risk assessment of pesticides according to current European legislation

In Europe, agencies and official organizations involved in the pesticide control such as the EFSA, ECHA, JRC and ECETOC or even the OECD are pointing out that the software tools based on quantitative structure relationship models, i.e. QSAR and QSPR, have a huge potential to improve the pesticide risk assessment process. In this sense, these non-animal test methods can promote the competitiveness of agriculture in this region: the consumer safety is increased with them due to the possibility of perform an overall better risk assessment of the degradation products and metabolites from pesticides. However, the use of theses computational-based (in silico) tools must be much more systematised and harmonised, improving their validation and including case studies to test them. To open databases, incorporating critical data in an orderly manner for building the models, becomes also necessary. Moreover, quantum chemistry through the Density Functional Theory should be promoted as tool for calculation of quantum descriptors, especially for the study of similar compounds with the same carbon skeleton but differing substitution patterns, e.g. isomers.

A multiplexed UPLC-MS/MS assay for the simultaneous measurement of urinary safety biomarkers of drug-induced kidney injury and phospholipidosis

Drug-induced kidney injury (DIKI) is a major concern in drug risk assessment given its clinical importance and the absence of a sensitive/specific method of diagnosis. Pharmaceutical regulatory agencies have qualified and issued letters of support for new biomarkers to better evaluate DIKI in nonclinical toxicity and clinical studies. Additional efforts have focused on drug-induced phospholipidosis (DIPL) and its potential link with collateral renal damage. The combined use of urinary biomarkers is an efficient way to evaluate renal safety in nonclinical and clinical studies. Eight FDA/EMA/PMDA qualified (or supported) urinary biomarkers, including kidney injury molecule-1 (KIM-1), β2-microglobulin (B2M), clusterin (CLU), cystatin C (CysC), trefoil factor 3 (TFF3), neutrophil gelatinase-associated lipocalin (NGAL), osteopontin (OPN), and alpha-glutathione S-transferase (α-GST), were quantified by multiplex UPLC-MS/MS in a repeat dose study of gentamicin in rats. Rats administered gentamicin at 100 mg/kg/day for 2 weeks developed renal lesions detected by histopathology. Biomarkers of tubular damage (CLU, KIM-1, OPN) increased 9.8, 34.7, and 35.6-fold (relative to concurrent controls), respectively, after 2 weeks of dosing. Biomarkers of glomerular damage and/or impairment of tubular reabsorption (CysC, B2M) increased 11.7 and 22.6-fold. NGAL and α-GST increased <3-fold after 2 weeks of dosing. TFF3 was comparable to concurrent controls. The elevated biomarker concentrations met PSTC threshold criteria and were consistent with mechanisms of gentamicin nephrotoxicity. Increased urinary di-22:6-BMP indicated concomitant DIPL as confirmed by TEM. This work provides evidence supporting the combined use of the DIKI biomarker panel and di-22:6-BMP as a biomarker of DIPL in drug risk assessment.

Regulatory science - JEMS symposium in 2014

The Public Symposium of the Japanese Environmental Mutagen Society (JEMS), entitled “Regulatory Science”, was held at the Shiba-Kyoritsu campus of Keio University, Tokyo, on May 24, 2014. The concept of regulatory science was first proposed by Dr. Mitsuru Uchiyama in 1987 as the science that reconciles the fruits of science and technology with the most desirable form for harmony between people and society, by making accurate predictions, assessments, and judgments, based on evidence. However, a quarter-century later, the perception (or attitude) of the masses towards this word appears to be diverse. The main aim of this symposium was to provide the concerned population, including the members of JEMS, with an opportunity to rediscover the role played by JEMS in regulatory science and to discuss the meaning and implications of regulatory science, as well as its development in Japan. The morning session comprised six lectures, including one special lecture, which introduced the regulatory science-related activities of the organizations closely relevant to JEMS. The afternoon session included five lectures on the issues of regulatory science, pertinent to the Food Safety Commission of Japan (FSCJ), which were followed by a panel discussion. This symposium highlighted the important contributions of JEMS toward development of regulatory science in Japan, in conjunction with the many challenges to be addressed. We believe that this symposium provided great scope for eliciting interest in regulatory science, in many members of the audience. It would be helpful if all members of the audience, as well as the readers of this article, would attempt to clarify the challenges presented in this symposium.