DNA methylation in liver and ovary tissues of Caspian Kutum broodstock and embryos (Rutilus Kutum) under genistein and β-sitosterol exposures

A wide range of chemical endocrine disrupters modifies DNA methylation. Like a weak class of estrogens, phytoestrogens can affect aquatic animal reproduction and disturb the structure of endocrine systems. In order to study the epigenetic effects of genistein and β-sitosterol, 49 female adults (for about 21 days) and fertilized eggs (until hatching time) of Kutum’s exposed to 3 different levels of genistein and β-sitosterol (10, 50, 500ng/l). At the end, the liver, the ovaries, and embryos were sampled and methylation-sensitive amplified polymorphism (MSAP) was used to evaluate the level of DNA methylation. According to result the fish exposed to high level of β-sitosterol shown hypo DNA methylation in the liver. Compared with control, both of these compounds could effect on the ovary and embryos DNA methylation pattern. The result showed, whole genome methylation had a different pattern in the liver, ovary, and embryos, which treated by 500ng/l of β-sitosterol. Methylation change pattern can be changed depends on the type of tissue and structure and level of the phytoestrogen compounds. According to this study, genistein and β-sitosterol could affect reproduction and embryo development by changing molecular indices. It seems that these compounds could affect the endocrine system of Kutum and reduce reproduction performance of Kutum in the long period.