Effects of maternal exposure to nano-alumina during pregnancy on neurodevelopment in offspring mice / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To observe the effects of maternal exposure to nano-alumina during pregnancy on the neurodevelopment in offspring mice.</p><p><b>METHODS</b>Female ICR mice began to be exposed to nano-alumina 10 d before mating, and the nano-alumina exposure lasted till offspring mice were born. All the female mice were randomly divided into 5 groups: solvent control group (saline), nano-carbon group (11.76 mg/ml), micro-alumina group (50 mg/ml), 50 nm alumina group (50 mg/ml), and 13 nm alumina group (50 mg/ml). All the mice were treated by nasal drip (10 µl/time) 3 times daily till offspring mice were born. Physiological indices, reflex and sensory function test, endurance test, Morris water maze test, positioning and navigation test, and open field test were used to evaluate the neurodevelopment of newborn mice.</p><p><b>RESULTS</b>On day 28, the body weight of 13 nm alumina group (16.73±4.04 g) was significantly lower than that of solvent control group (20.45±2.50 g) (P<0.01); the 13 nm alumina group had significantly delayed time to ear opening compared with the solvent control group (4.91±0.78 d vs 4.45±0.50 d, P<0.01); compared with the solvent control group, the nano-carbon group, micro-alumina group, 50 nm alumina group, and 13 nm alumina group had significantly delayed time to eruption of teeth (10.05±0.23 d vs 10.32±0.48 d, 10.75±0.45 d, 10.32±0.47 d, and 10.79±0.49 d, P<0.05 or P<0.01). On days 4 and 7 after birth, compared with the solvent control group, other groups had significantly decreased proportions of mice which passed the cliff avoidance test (P < 0.05 or P < 0.01). On days 12 and 14 after birth, compared with the solvent control group, the nano-carbon group, 50 nm alumina group, and 13 nm alumina group had significantly reduced pre-suspension time in the endurance test (P < 0.05 or P < 0.01). The Morris water maze and positioning and navigation tests showed that the 13 nm alumina group had a significantly increased 5 d incubation period compared with the solvent control group (P < 0.05); compared with the solvent control group, other groups had significantly reduced numbers of platform crossings (P < 0.05 or P < 0.01). The open field test showed that the nano-carbon group and 13 nm alumina group had reduced numbers of rearings compared with the solvent control group (P < 0.05); compared with the solvent control group, other groups had significantly reduced numbers of modifications (P < 0.01).</p><p><b>CONCLUSION</b>Maternal exposure to nano-alumina (13 nm) during pregnancy has inhibitory effects on the physical development and early behavioral development in newborn mice and can also inhibit the learning and memory abilities and adaptability to new environment in offspring mice. The neurodevelopmental toxicity of nano-alumina to newborn mice increases as the particle sizes of nano-alumina decrease, which has been demonstrated by the endurance test and number of rearings.</p>

Changes of brain oxidative stress induced by nano-alumina in ICR mice / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the brain oxidative stress injury induced by nano-alumina particles in ICR mice.</p><p><b>METHODS</b>Sixty male ICR mice were randomly divided into 6 groups: control group, solvent control group, 100 mg/kg micro-alumina particles group, 3 groups exposed to nano-alumina particles at the doses of 50, 100 and 200 mg/kg. The mice were exposed by nasal drip for 30 days. Then levels of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-PX) in brain tissues of mice were detected.</p><p><b>RESULTS</b>There was no difference of SOD activity in mouse brain between control group [(17.32 +/- 6.23)U/gHb] and 50 mg/kg nano-alumina particles group [(17.89 +/- 1.82) U/gHb]. The SOD activity [(4.93 +/- 2.30)U/gHb] in 200 mg/kg nano-alumina particles group was significantly lower than that in control group (P < 0.05). The MDA levels in 3 nano-alumina particles groups were (0.76 +/- 0.13), (1.00 +/- 0.30) and (1.16 +/- 0.39)nmol/ml, respectively, which were significantly higher than that [( 0.24 +/- 0.09)nmol/ml] in control group (P < 0.05). The GSH levels in 3 nano-alumina particles groups were (0.72 +/- 0.08), (0.55 +/- 0.19) and (0.61 +/- 0.20)mg/gpro, respectively, which were significantly lower than that [(1.55 +/- 0.34)mg/gpro]] in control group (P < 0.05). The CAT activity in 50 and 100 mg/kg nano-alumina particles groups were (10.40 +/- 3.84) and (10.40 +/- 2.00)U/mgpro, respectively, which were significantly higher than that [(5.79 +/- 0.96) U/mgpro] in control group (P < 0.05). The CAT activity [(3.25 +/- 1.04)U/mgpro] in 200 mg/kg nano-alumina particles group was significantly lower than that in control group (P < 0.05 ).</p><p><b>CONCLUSION</b>Nano-alumina particles can induce the oxidative stress damage in brain tissues of mice.</p>