Abstract
The manuscripts of this special issue of Current Pharmaceutical Design cover a wide spectrum of relevant and fascinating topics in the area of developmental and reproductive toxicology. Experimental studies have consistently shown that commonly prescribed therapeutic agents can decrease embryonic cardiac output, leading to periods of embryonic hypoxia causing malformations or embryonic death. The article authored by Webster and co-workers [1] describes the available experimental data on the subject and discusses the potential consequences of drug-induced reduction in cardiac output in the human embryo. Alcohol is a well established human teratogen. It has been estimated that the incidence of Fetal Alcohol Syndrome (FAS), which is the most severe manifestation within the fetal alcohol spectrum disorders, is about 1 per 1000 in industrialized countries. In their review, Brennan and Giles [2] pay specific attention on the noxious effects of alcohol exposure on eye development. Insightful discussion on the mechanistic role played by sonic hedgehog pathway disruption is also provided. The potential of foreign compounds to induce ovarian damage, leading to ovarian reserve depletion or cancer, is a topic of increasing global concern. Iorio and co-workers [3] review the noxious effects induced by some widely diffused xenobiotics and by common anticancer therapies on ovary function. Research priorities for the development of preventive measures are also highlighted. Perobelli [4] focuses on male reproductive aspects in prepubertal toxicity assays. The human prepubertal phase has been regarded as a phase of reproductive tract quiescence and reduced vulnerability to toxicants, but emerging data suggest it may represent a susceptible window to endocrine disrupting chemicals. The paper presented by Kanungo et al. [5] summarizes current perspectives on the zebrafish model, which is emerging as a promising alternative animal model for developmental toxicity screening. The elevated potentiality for high-throughput screening is one of the remarkable features offered by this model system. Glucocorticoids play important roles in skeletogenesis. Cheng et al. [6] provide an update on the effects of the synthetic corticosteroid agent dexamethasone on embryo skeletogenesis. The potential impact of glucocorticoids on key regulators of embryo skeletogenesis, including BMPs, FGFs, Hedgehog and Wnt signaling pathways, is also discussed. Histone deacetylases (HDAC) are a family of enzymes playing an important role in the modulation of the transcriptional state of many regions of the genome. Inhibitors of HDAC are promising therapeutic agents in several conditions, including solid and hematological cancers. Updated research information on the teratogenic effects elicited by this class of agents is presented by Giavini and Menegola [7]. Nitric oxide (NO) is multifunctional gaseous molecule, playing crucial roles in the mediation of a wide spectrum of biological processes. The concept that optimal NO levels are essential for normal embryonic development is supported by an increasing number of experimental studies. This topic is reviewed by Tiboni and Ponzano [8].