Expression and role of anti-oxidative damage factors in the placenta of preterm infants with premature rupture of membranes / 中国当代儿科杂志

OBJECTIVES@#To study the association of the anti-oxidative damage factors nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and NAD(P)H:quinone oxidoreductase-1 (NQO1) with preterm premature rupture of membranes (PPROM).@*METHODS@#A prospective study was conducted. The neonates who were hospitalized in Yanbian Hospital from 2019 to 2020 were enrolled as subjects, among whom there were 30 infants with PPROM, 32 infants with term premature rupture of membranes (TPROM), and 35 full-term infants without premature rupture of membranes (PROM). Hematoxylin and eosin staining was used to observe the inflammatory changes of placental tissue. Immunohistochemical staining was used to measure the expression of Nrf2, HO-1, and NQO1 in placental tissue. Western blot was used to measure the protein expression levels of Nrf2, HO-1, and NQO1 in placental tissue.@*RESULTS@#Compared with the PPROM group, the TPROM group and the non-PROM full-term group had significantly higher positive expression rates and relative protein expression levels of Nrf2, HO-1, and NQO1 in placental tissue (P<0.05). There were no significant differences in the positive expression rates and relative protein expression levels of Nrf2, HO-1, and NQO1 in placental tissue between the TPROM and non-PROM full-term groups (P>0.05).@*CONCLUSIONS@#The low expression levels of Nrf2, HO-1, and NQO1 in placental tissue may be associated with PPROM, suggesting that anti-oxidative damage is one of the directions to prevent PPROM.

Impact of subchronic exposure to low-dose nano-nickel oxide on the reproductive function and offspring of male rats / 中华男科学杂志

Objective@#To investigate the influence of subchronic exposure to low-dose subchronic nano-nickel oxide (NNO) on the reproductive function of male rats and embryonic development of the pregnant rats.@*METHODS@#Fifty normal healthy male SD rats weighing 180－220 g were randomly divided into five groups of equal number, negative control, 4 mg/ml micro-nickel oxide (MNO), and 0.16, 0.8 and 4 mg/ml NNO, those of the latter four groups exposed to MNO or NNO by non-contact intratracheal instillation once every 3 days for 60 days, and then all mated with normal adult female rats in the ratio of 1∶2. After the female animals were confirmed to be pregnant, the males were sacrificed and the weights of the body, testis and epididymis obtained, followed by calculation of the visceral coefficients, determination of epididymal sperm concentration and viability and the nickel contents in the blood and semen by atomic fluorescence spectrometry. The female rats were killed on the 20th day of gestation for counting of the implanted fertilized eggs and live, dead and resorbed fetuses.@*RESULTS@#After 60 days of exposure, the rats of the NNO groups showed no statistically significant differences from those of the negative control and MNO groups in the weights of the body, testis and epididymis or visceral coefficients. Compared with the negative control group, the animals of the 0.8 and 4 mg/ml NNO groups exhibited markedly decreased sperm concentration (［9.36 ± 0.98］ vs ［7.49 ± 1.46］ and ［6.30 ± 1.36］ ×10⁶/ml, P < 0.05) and viable sperm (［85.35 ± 9.16］% vs ［68.26 ± 16.63］% and ［65.88 ± 14.68］ %, P < 0.05), increased morphologically abnormal sperm (［8.30 ± 2.47］% vs ［13.99 ± 4.87］% and ［15.38 ± 8.86］ %, P < 0.05), and elevated rate of dead and resorbed fetuses (1.18% vs 6.89% and 7.37%, P < 0.05), blood nickel content (［0.13 ± 0.16］ vs ［0.52 ± 0.34］ and ［0.82 ± 0.44］ mg/L, P < 0.05) and semen nickel content (［0.08 ± 0.13］ vs ［0.35 ± 0.23］ and ［0.63 ± 0.61］ mg/L, P < 0.05). The nickel level in the semen was correlated significantly with that in the blood (r = 0.912, P <0.01), negatively with the rate of viable sperm (r = －0.879, P <0.01) and positively with the percentage of morphologically abnormal sperm (r = －0.898, P <0.01).@*CONCLUSIONS@#Sixty-day exposure to nano-nickel oxide at 0.8 and 4 mg/ml can produce reproductive toxicity in male rats and result in fetal abnormality in the females, while that at 0.16 mg/ml has no significant toxic effect on the reproductive function of the males.