Relative potency ranking of azoles altering craniofacial morphogenesis in rats: An in vitro data modelling approach

Abstract

 Whole embryo culture as an alternative method for pesticide hazard evaluation.  Ranking of azole pesticide activity on embryo development  In vitro evaluation of craniofacial primordia defects induced by azoles  Comparison between azole and retinoic acid dysmorphogenic activity *Accepetd manuscript Click here to view linked References 2 ABSTRACT Facial malformations represent one of the most frequent abnormality in humans. The adverse outcome pathway involved in facial defects seems to be related to retinoic acid (RA) pathway imbalance. Environmental agents inducing cranio-facial malformations in experimental models include pesticides (especially azole fungicides). By using the in vitro alternative method postimplantation rat whole embryo culture (WEC), we evaluated the intrinsic embryotoxic activity of some azole antifungals (cyproconazole, CYPRO; triadimefon, FON; flusilazole, FLUSI and prochloraz, PCZ), in comparison to RA. All the tested molecules induced in a dose-related manner specific defects of the cranio-facial structures (fused branchial arches), similar to those induced by RA. Collected data were modelled by using PROAST 65.5 software in order to characterize the relative potency factors (RPFs) versus RA. In comparison to RA, all the evaluated azoles were less potent, showing among them a similar potency. Our data suggest a possible azole-related RA signaling perturbation to be further investigated. Moreover, the present results indicate the approach used in this work as an interesting tool applicable to the hazard evaluation of novel compounds or assessment of combined exposure to azoles or other dismorphogens.

Quantitative AOP based teratogenicity prediction for mixtures of azole fungicides

“…As reported in Di Renzo et al (2019), dose-related teratogenic effects were detected in embryos exposed to the different chemicals. The specific target for all tested azoles was the branchial apparatus, which was also affected by RA exposure.…”

“…Experimental data on frequencies of malformations of the branchial arches following exposure to RA, individual azoles (CYPRO, FLUSI, FON) and binary mixtures (increasing concentrations of one azole + the lowest-effect concentration of another azole), obtained in our laboratory in Milano (Di Renzo et al 2019), were used in this study (Table 1). All the tested compounds were purchased from Sigma, Italy.…”

Retrospective cumulative dietary risk assessment of craniofacial alterations by residues of pesticides

“…In the frame of EuroMix project, specific RA-like teratogenic effects at the level of the branchial structures were correlated to exposure to certain antifungal azoles (triadimefon, cyproconazole and flusilazole) selected on the basis of results from previous Whole Embryo Culture (WEC) experiments 33 Available online: https://www.rivm.nl/en/international-projects/euromix (Di Renzo et al, 2019), the histone deacetylases inhibitor valproic acid, and RA (as reference molecule). The suggested hypothetical pathogenic pathway for azoles, which includes CYP26 inhibition as MIE (Menegola et al, 2006), was the basis for developing AOP for craniofacial malformations (Metruccio et al, 2020).…”