Silver nanoparticles (NPs), widely used in the manufacture of various types of consumer products and for medical applications, belong to novel types of materials that pose potential risks to human health. The potential negative effects of the influence of these NPs on reproduction are insufficiently researched. A quantitative assessment of the transfer of metallic silver nanoparticles through the placenta and breast milk was carried out during an in vivo experiment. We used 34.9 ± 14.8 nm in size silver NPs that were stabilized by low-molecularweight polyvinylpyrrolidone and labeled with the 110mAg radioactive isotope using thermal neutron irradiation in a nuclear reactor. [110mAg]-labeled NPs preparations were administered intragastrically via a gavage needle to pregnant (20th day of gestation) or lactating (14–16th day of lactation) female rats at a dose of 1.69–2.21 mg/kg of body weight upon conversion into silver. The accumulation of NPs in rat fetuses and infant rats consuming their mother’s breast milk was evaluated using a low-background semiconductor gamma-ray spectrometer 24 and 48 hours following labeling, respectively. In all cases, we observed a penetration of the [110mAg]-labeled NPs through the placenta and ther entry into the mother’s milk in amounts exceeding by 100-1,000 times the sensitivity of the utilized analytical method. The average level of accumulation of NPs in fetuses was 0.085–0.147% of the administered dose, which was comparable to the accumulation of the label in the liver, blood, and muscle carcass of adult animals and exceeded the penetration of NPs across the hematoencephalic barrier into the brain of females by a factor of 10-100. In lactating females, the total accumulation of [110mAg]-labeled NPs into the milk exceeded 1.94 ± 0.29% of the administered dose over a 48 h period of lactation; not less than 25% of this amount was absorbed into the gastrointestinal tract of infant rats. Thus, this was the first time experimental evidence of the transfer of NPs from mother to offspring through the placenta and breast milk was obtained.

We compared anxiety, neuromotor, and cognitive functions in mutant rats with different allelic variants of dopamine transporter DAT knockout receiving balanced or excess in fat and fructose diet. The experiments were performed in DAT −/− homozygotes, DAT +/− heterozygotes, and DAT +/+ wild type rats. The genotype of DAT ‐ KO rats was confirmed by restriction analysis of DAT gene compared to behavioral responses in the open field test ( OF ). Animals in the first groups of each strain were fed a balanced AIN 93M diet; and those in the second groups with a high‐fat/high‐fructose diet. Neuromotor function was studied as grip strength, and behavioral responses were assessed in the elevated plus maze and conditioned passive avoidance response tests. The mass of the internal organs and white and brown fat, as well as selected lipid and nitrogen metabolism parameters in blood plasma were determined at the end of the experiment. DAT −/− had the highest specific grip strength, and showed an increase in initial exploratory activity in comparison with DAT +/− and DAT +/+. The exploratory activity was significantly reduced in the second test compared to the first one in DAT −/− and DAT +/− of first but not second group. Anxiety decreased with age in the second groups of DAT +/− and DAT +/+ (but not in DAT −/−) and was higher in DAT +/+ than in DAT +/− and DAT −/−. Excess fat and fructose resulted in the deterioration of short‐term memory in DAT +/+. Lipidomic indices of blood plasma were less responsive to diet in DAT −/− and DAT −/+ in comparison to DAT +/+. The increased As AT /Al AT activity ratio in DAT −/− compared with those in DAT +/+ suggests the activation of catabolism activity in the mutants. The consumption of excess fat and fructose significantly modified the effects produced by DAT gene allelic variants presumably due to the influence on the processes of dopamine metabolism.

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