Effects of prenatal exposure to single-wall carbon nanotubes on reproductive performance and neurodevelopment in mice

Abstract

Carbon nanotubes with extraordinary properties may become a novel drug and gene delivery tool in nanomedicine; however, insufficient information is available regarding their biosafety. Therefore, this work was performed to study the effect of prenatal exposure of single-walled carbon nanotubes (SWCNTs) on reproductive and neurobehavioral endpoints in mice. Thirty pregnant female mice were assigned to three groups (n = 10 for each group). The two treated groups were injected intraperitoneally (i.p.) with 1 or 10 mg/kg body weight (b.w.) of SWCNTs suspended in 1 ml of phosphate buffer saline (PBS) on gestational days 0 and 3. The control group was injected i.p. with an equal volume of PBS. The neurobehavioral ontogeny of pups was evaluated using a modified Fox battery. A decrease in litter size on postnatal day 2 was observed in the group treated with 10 mg/kg b.w. of SWCNTs whereas no significant differences between groups were observed in any other parameters. The behavioral development of pups did not show significant differences during growth except for the surface righting reflex, which showed significant delay compared to control in the group treated with 1 mg/kg b.w. SWCNTs. Moreover, exposed offspring (10 mg/kg b.w. SWCNTs) displayed enhanced anxiety in the elevated plus maze; however, other ethological analysis (Morris water maze and open field test) did not show behavioral changes in the experimental groups. In conclusion, the present results demonstrated small changes in offspring sensory and motor development following exposure to SWCNTs and support the idea that SWCNT risk assessment merits further investigation.

Neurobehavioral toxicity of carbon nanotubes in mice

“…We recently showed that mouse offspring of mothers that were i.p. exposed to 10 mg kg À1 pristine SWNTs identical to SWNTs used in the present study were overtly anxious but showed similar locomotor activity compared to control pups in EPM (Ivani et al, 2014). To the best of our knowledge, the molecular mechanisms that govern anxiogenic effects of CNTs have not been reported.…”

Measuring Preweaning Sensorial and Motor Development in the Mouse

“…The metric qualities of the tests are satisfactory or good. They have a good sensitivity and they discriminate subtle differences in environment (Carlier, Roubertoux, & Cohen‐Salmon, ; Dulioust et al., ) and in drug exposure (Ivani, Karimi, Tabatabaei, & Syedmoradi, ). Many publications confirm that genetic events impact the behaviors that are measured by the tests (Willing & Wagner, ).…”

Prenatal Stress Impairs Postnatal Learning and Memory Development via Disturbance of the cGMP–PKG Pathway and Oxidative Phosphorylation in the Hippocampus of Rats

“…The behavioral assessment of the offspring (Smart and Dobbing, 1971;Chiavegatto et al, 1997;Chen et al, 2012;Ivani et al, 2016) was conducted as follows. The number, the weights, and the changes in weight of the pups for each dam were recorded and analyzed statistically.…”

“…The physical development and the maturation of the pups were evaluated using the methodology proposed by Smart and Dobbing (1971), Chiavegatto et al (1997), Chen et al (2012), and Ivani et al (2016). First, the dates on which surface righting reflexes occurred were recorded (Ivani et al, 2016), with the test performed during postnatal days (PNDs) 4-21, by gently placing the pup in a supine position and observing whether it could right itself and bring all four of its limbs into contact with the surface within 3 s. Those that succeeded were considered to have met the standard. Next, the dates of eye opening (beginning during PNDs 10-16), incisor eruption (beginning on PND 11), and ear opening (beginning on PND 15) were noted.…”

“…Next, the dates of eye opening (beginning during PNDs 10-16), incisor eruption (beginning on PND 11), and ear opening (beginning on PND 15) were noted. Then, beginning on PND 12, we assessed whether the pups could perform the auditory startle reflex (Ivani et al, 2016), showing a whole-body startle response in response to a loud clap of the hands at less than 15 cm away. These tests were performed until 100% of the pups reached each developmental milestone.…”