Phenotypic and epigenetic effects of vinclozolin in the gastropod Physella acuta

Abstract

Vinclozolin (VZ) is an endocrine-disrupting chemical that is able to interact with the endocrine system of mammalian models directly via receptor-binding and indirectly via the epigenetic regulation of DNA methylation. Gastropods often respond sensitively to chemicals classified as endocrine disrupting chemicals, but information on epigenetics is almost absent for this group. In order to investigate potential phenotypic and epigenetic effects of VZ in gastropods, we performed a two-generation study with the freshwater snail Physella acuta. The parental generation (F0) of P. acuta was exposed to 0.01, 0.1, 10 and 100 μg l-1 VZ. VZ-exposed F0 and nonexposed offspring of the control, 0.1 and 100 μg l-1 groups (F1 and F2) were investigated for phenotypic (reproduction, growth and embryo development) and epigenetic (5-methyl cytosine content) effects. VZ exposure of F0 did not induce an adverse reproductive phenotype in P. acuta. However, the size of F1 adults and the mortality of F2 embryos significantly increased when F0 adults were previously exposed to 100 μg l-1 VZ. At the level of global DNA methylation, we did not observe a VZ effect, but global DNA methylation of P. acuta decreased with increasing age. VZ affected the offspring of 100 μg l-1 VZ-exposed individuals, most probably due to an indirect VZ exposure of F1 (embryonic stage) and F2 (germline). The postulated relationship between VZ phenotype and epitype was not shown by the present study. However, our results demonstrate for the first time the presence and age-dependence of DNA methylation in P. acuta.