Effects of nonylphenol exposure via placenta on early nervous reflex and locomotives of offspring in rat / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the influence of nonylphenol (NP) on the neural behavioral development of filial generation rats exposed via placenta.</p><p><b>METHODS</b>On the first day of the pregnancy, the SD rats were divided into four groups, and orally administered with NP at doses of 0, 50, 100 and 200 mg/kg on gestational day 9 approximately 15 respectively. The offspring rats of each groups were examined to observe the impact of NP on the early physiological, neurobehavioral development. The changes of filial generation body weight (from generation day 1 to 28) were measured. Brain tissues were stained with Hematoxylin-eosin and Congo red to observe with optical microscope.</p><p><b>RESULTS</b>In contrast to the control group, the early physiological markers (pinna detachment, hair growth, tooth growth and eye opening) and the early neurobehavioral development indices (surface righting, air righting, acoustic startle and visual placing) were significantly delayed in the groups of NP 200mg/kg dose (P < 0.05). The developing time of physiological markers decreased from (4.5 +/- 0.8, 5.2 +/- 0.8, 12.7 +/- 1.4, 16.0 +/- 1.7) d to (3.6 +/- 0.5, 3.6 +/- 0.5, 11.1 +/- 1.1, 12.7 +/- 1.3) d while neurobehavioral developing time decreased from (6.5 +/- 0.8, 11.3 +/- 0.5, 11.2 +/- 1.0, 20.2 +/- 1.0) d to (5.1 +/- 0.4, 8.3 +/- 0.5, 9.3 +/- 0.5, 9.3 +/- 0.5) d (P < 0.05 or P < 0.01). The body weights of filial generation rats were decreased obviously from 1 st day to 28th day. Histopathological examination displayed that hippocampal neurons had congestion and oedema in the group of 100, 200 mg/kg dose.</p><p><b>CONCLUSION</b>Exposures to NP during gestation might impair the neurobehavioral development of F1 rats significantly.</p>

Preliminary study of biomarker in blood or cerebrospinal fluid of rat following manganese exposure / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the biomarkers of manganese exposure by measuring the manganese (Mn) and iron (Fe) level as well as the mRNA change of Hepcidin, divalent metal-ion transporter-1 (DMT1) and Parkin-2, one of genes related to Parkinson disease in body fluid and brain tissues of rat.</p><p><b>METHODS</b>Male Sprague-Dawley rats were administered (i.p) either MnCl2 solution (6 mg Mn/kg) or the same volume saline, 5 times per week and for 4 weeks. Graphic furnace Atom Absorption Spectrum (AAS) was applied to measure the concentration of Mn and Fe in brain tissue and body fluids. Meanwhile Hepcidin, DMT1 and Parkin-2 mRNA expression were detected by real-time RT-PCR.</p><p><b>RESULTS</b>Mn concentration in erythrocytes of rats was the 86.9 folds of that in control; No significant change was found in plasma. However the trend and range of Mn increase in cerebrospinal fluid (CSF) was the same as that in brain tissue including striatum, cortex, hippocampus and choroid plexus. Meanwhile Fe concentration in brain tissue of Mn exposed rats was also higher than that of control, whose trend was as same as that in CSF. However iron concentration in plasma decreased. The real-time RT-PCR data also showed that Hepcidin mRNA expression in Mn-exposed rat decreased 56% in blood, which was in line with its expression in cortex(67%). Similarly, Parkin-2 mRNA expression decreased both in blood (42%) and in striatum. However DMT1 mRNA expression increase 38% in striatum of Mn-exposed rats but decreased in blood.</p><p><b>CONCLUSION</b>Hepcidin and Parkin-2 mRNA expression in blood might be serves as the effective biomarkers following manganese exposure, certainly which needs to be further explored.</p>

Early biological markers of manganese exposure / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the biomarker of manganese exposure by analyzing the relationship between manganese exposure and concentration in some biomaterials.</p><p><b>METHODS</b>The air samples were collected through the individual air sample. According to the manganese levels in the air, workers were assigned to control group, low concentration group and high concentration group, and manganese in the hair, urine, serum, blood cell and saliva from different group were measured respectively. The correlations between concentration of external manganese exposure and manganese concentrations in biomaterials, and years of employment and concentrations in biomaterials were analyzed.</p><p><b>RESULTS</b>In the high concentration group, saliva manganese was 32.17 µg/L, hair manganese was 37.39 mg/kg, urine manganese was 2.50 µg/L, plasma manganese was 29.61 µg/L, blood manganese was 14.49 µg/L, were higher than those in the control group (10.40 µg/L, 1.60 mg/kg, 0.77 µg/L, 10.30 µg/L, 4.56 µg/L respectively) (P < 0.01). The manganese concentration in the saliva was significantly correlated with airborne manganese concentration (r = 0.649, P < 0.01), with the years of employment (r = 0.404, P < 0.01), with the total exposure of manganese (r = 0.342, P < 0.01), with the manganese concentration of plasma (r = 0.303, P < 0.01) and with the manganese concentration in blood cells (r = 0.359, P < 0.01), respectively.</p><p><b>CONCLUSIONS</b>The concentration of manganese in saliva could work as a biomarker of manganese internal exposure.</p>