Application of quantitative structure-activity relationships for modeling drug and chemical transport across the human placenta barrier: a multivariate data analysis approach

Pharmacological agents and environmental pollutants can transfer from mother to fetus across the placental barrier, leading to reproductive toxic effects. Ex vivo human placental perfusion constitutes the most widely used method to study placental transfer and metabolism of drugs and chemicals. The aim of the present study was to evaluate whether quantitative structure-activity relationship (QSAR) methodology could serve as an effective alternative tool to estimate drugs and chemicals transport across the human placental barrier on the basis of easily interpretable molecular, physicochemical and structural properties. Multivariate data analysis (MVDA) was applied to a set of 88 structurally diverse drugs and chemicals to model placental transfer expressed by clearance index values compiled from literature sources. An adequate and robust QSAR model (r(2) = 0.73, Q(2) = 0.71, RMSEE = 0.15) was established, providing an informative illustration of the contributing physicochemical, molecular and structural properties of the compounds in placental transfer process. Descriptors reflecting the polarity of compounds proved to be the most important with a negative sign. Lipophilicity and, at a lower extent, molecular size parameters exerted positive contribution in the model. Thus, QSAR analysis may be considered as a promising alternative tool to support high-throughput screening of drugs and chemicals in respect to their transport across placental barrier. Copyright (C) 2009 John Wiley & Sons, Ltd.