Diesel exhaust affects immunological action in the placentas of mice

We investigated the effect of diesel exhaust (DE) on pregnancy and fetal development in mice at day 14 postcoitum (pc) with a special focus on the placenta. The number of absorbed fetuses increased in groups exposed to DE, and congestion was observed in histological sections of placentas. During placental absorption expression of CYP1A1 mRNA decreased to undetectable levels, whereas expression of TNF alpha mRNA increased approximately twofold over that of the control. Levels of CYP1A1 mRNA in normal placentas from DE-exposed mice were unchanged. mRNA levels of inflammatory cytokines IL-2, IL-5, IL-12 alpha, IL-12 beta, and GM-CSF increased in placentas exposed to DE (0.3 and 3.0 mg diesel exhaust particles (DEP)/m3). Expression of IL-5 mRNA was markedly increased in DE-exposed placentas, although levels were barely detectable in control placentas. IL-6 mRNA expression was increased approximately 10-fold in placentas exposed to DE (3.0 mg DEP/m3). It has been reported that expression of mRNA encoding proteins involved in immune function in the placenta is increased during fetal absorption in mice. In the present study, expression of such mRNA by the placenta was increased by DE exposure. Because it is believed that expression of mRNA in the placenta also affects fetal development, DE may promote fetal absorption. These findings suggest that in mice exposure to DE affects fetal absorption and placental function by modifying expression of immune-related genes during early gestation and expression of endocrine-related genes during late gestation.     

Diesel exhaust (DE) affects the regulation of testicular function in male Fischer 344 rats

To investigate the effects of diesel exhaust (DE) particles on the reproductive system, male Fischer 344 rats at 13 mo of age were exposed to clean air or DE at particle concentrations of 0.3, 1, or 3 mg/m3 for 8 mo. DE did not markedly affect testicular and body weights. However, DE at 0.3 mg/m3 significantly decreased prostate and coagulating gland weights, accompanied by a reduction in thymus and adrenal gland weight. In contrast, there was a significant rise in the weights of prostate, seminal vesicles, and coagulating glands in the 3 mg/m3 DE group. In rats exposed to 0.3 or 1 mg/m3 DE, serum luteinizing hormone (LH) and testosterone increased significantly, while a rise in testicular testosterone was noted with 3 mg/m3 DE. The concentrations of follicle-stimulating hormone (FSH) and inhibin as well as the sperm head counts were not markedly altered in any treatment group. Positive staining with inhibin-alpha subunit and 3beta-hydroxysteroid dehydrogenase (3beta-HSD) were observed in Sertoli cells and Leydig cells, respectively. Immunolocalization of inhibin-alpha subunit and 3beta-HSD was not changed by exposure to DE. In conclusion, DE appears to exert greater effects on accessory glands than on testes in Fischer 344 rats, and the responsiveness of rats is less than that found in mice.     

Diesel exhaust particles induce endothelial dysfunction in apoE-/- mice

BACKGROUND: Particulate air pollution can aggravate cardiovascular disease by mechanisms suggested to involve translocation of particles to the bloodstream and impairment of endothelial function, possibly dependent on present atherosclerosis. AIM: We investigated the effects of exposure to diesel exhaust particles (DEP) in vivo and ex vivo on vasomotor functions in aorta from apoE(-/-) mice with slight atherosclerosis and from normal apoE(+/+) mice. METHODS: DEP 0, 0.5 or 5 mg/kg bodyweight in saline was administered i.p. The mice were sacrificed 1 h later and aorta ring segments were mounted on wire myographs. Segments from unexposed mice were also incubated ex vivo with 0, 10 and 100 microg DEP/ml before measurement of vasomotor functions. RESULTS: Exposure to 0.5 mg/kg DEP in vivo caused a decrease in the endothelium-dependent acetylcholine elicited vasorelaxation in apoE(-/-) mice, whereas the response was enhanced in apoE(+/+) mice. No significant change was observed after administration of 5 mg/kg DEP. In vivo DEP exposure did not affect constriction induced by K(+) or phenylephrine. In vitro exposure to 100 microg DEP/ml enhanced acetylcholine-induced relaxation and attenuated phenylephrine-induced constriction. Vasodilation induced by sodium nitroprusside was not affected by any DEP exposure. CONCLUSION: Exposure to DEP has acute effect on vascular functions. Endothelial dysfunction possibly due to decreased NO production as suggested by decreased acetylcholine-induced vasorelaxation and unchanged sodium nitroprusside response can be induced by DEP in vivo only in vessels of mice with some atherosclerosis.     

Repeated inhalation of crack-cocaine affects spermatogenesis in young and adult mice

To investigate the effects of repeated crack-cocaine inhalation on spermatogenesis of pubertal and mature Balb/c mice, ten young (Y^ex) and ten adult (A^ex) Balb/c mice were exposed to the smoke from 5 g of crack with 57.7% of pure cocaine in an inhalation chamber, 5 days/week for 2 months. The young (Y^c) and adult (A^c) control animals (n = 10) were kept in a specially built and controlled animal house facility. The morphologic analysis of both testes of all animals included the analysis of quantitative and qualitative histologic parameters to assess the effect of crack-cocaine on spermatogenesis and Leydig cells. Apoptosis was determined by immunolabeling with caspase-3 antibodies. Compared to the Y^c animals, Y^ex animals showed a significant reduction in the number of stage VII tubules per testis (p = 0.02), Sertoli cells (p < 0.001) and elongated spermatids (p = 0.001). Comparisons between the Y^ex and A^ex groups identified a significant reduction in the number of Sertoli cells (p < 0.001) and round spermatids (p < 0.001) in the Y^ex group and a significant increase in apoptotic Leydig cells (p = 0.04) in the A^ex group. The experimental results indicate that crack-cocaine smoke inhalation induced spermatogenesis disruption in chronically exposed mice, particularly in pubertal mice.     

Repeated inhalation of crack-cocaine affects spermatogenesis in young and adult mice

To investigate the effects of repeated crack-cocaine inhalation on spermatogenesis of pubertal and mature Balb/c mice, ten young (Y(ex)) and ten adult (A(ex)) Balb/c mice were exposed to the smoke from 5 g of crack with 57.7% of pure cocaine in an inhalation chamber, 5 days/week for 2 months. The young (Y(c)) and adult (A(c)) control animals (n = 10) were kept in a specially built and controlled animal house facility. The morphologic analysis of both testes of all animals included the analysis of quantitative and qualitative histologic parameters to assess the effect of crack-cocaine on spermatogenesis and Leydig cells. Apoptosis was determined by immunolabeling with caspase-3 antibodies. Compared to the Y(c) animals, Y(ex) animals showed a significant reduction in the number of stage VII tubules per testis (p = 0.02), Sertoli cells (p < 0.001) and elongated spermatids (p = 0.001). Comparisons between the Y(ex) and A(ex) groups identified a significant reduction in the number of Sertoli cells (p < 0.001) and round spermatids (p < 0.001) in the Y(ex) group and a significant increase in apoptotic Leydig cells (p = 0.04) in the A(ex) group. The experimental results indicate that crack-cocaine smoke inhalation induced spermatogenesis disruption in chronically exposed mice, particularly in pubertal mice.     

Toxicity of inhaled chloroform in pregnant mice and their offspring

The effect of inhaled chloroform on embryonal and fetal development was evaluated in CF-1 mice. Bred mice were exposed to 0 or 100 ppm of chloroform for 7 hr/day from Days 1 through 7, 6 through 15, or 8 through 15 of gestation. Exposure to chloroform from Days 1 through 7 or 6 through 15 significantly impaired the ability of the female rats to maintain pregnancy but was not significantly teratogenic. In comparison, a significant increase in the incidence of cleft palate was observed among the offspring of mice inhaling chloroform from Days 8 through 15 of gestation, but no effect on the ability of the female rats to maintain pregnancy was discerned. Other signs of toxicity observed among the litters of mice exposed to chloroform included: decreased ossification of bones (all experimental groups), decreased incidence of resorptions (Days 1 through 7), and reduced fetal body measurements (Days 1 through 7 and 8 through 15).     

Nanoparticle-rich diesel exhaust affects hippocampal-dependent spatial learning and NMDA receptor subunit expression in female mice

We investigated the effect of exposure to nanoparticle-rich diesel exhaust (NRDE) on hippocampal-dependent spatial learning and memory function-related gene expressions in female mice. Female BALB/c mice were exposed to clean air, middle-dose NRDE (M-NRDE), high-dose NRDE (H-NRDE) or filtered diesel exhaust (F-DE) for three months. A Morris water maze apparatus was used to examine spatial learning. The expression levels of the N-methyl-D-aspartate (NMDA) receptor subunit, proinflammatory cytokines and neurotrophin mRNAs in the hippocampus were then investigated using real-time RT-PCR. Mice exposed to H-NRDE required a longer time to reach the hidden platform and showed higher mRNA expression levels of the NMDA receptor subunit NR2A, the proinflammatory cytokine CCL3, and brain-derived neurotrophic factor (BDNF) in the hippocampus, compared with the findings in the control group. These results indicate that three months of exposure to NRDE affected spatial learning and memory function-related gene expressions in the female mouse hippocampus.     

异氟烷对幼龄小鼠生长发育趋势的影响

目的研究异氟烷对幼龄小鼠生长发育趋势的影响。方法按随机分层方法,将64只幼龄小鼠分为2大组,再按完全随机分组方法,将每大组各分为4小组(n=8),即NS组(生理盐水组)、Iso1组、Iso2组和Iso3组,1～5d用跳台仪和避暗仪分别训练小鼠,并测得各组幼龄小鼠体质量。结果避暗训练和跳台训练中,各组幼龄小鼠生长发育趋势不同。在避暗和跳台训练中,NS组、Iso1组在2～3d间体质量出现了下降或增长缓慢的趋势,而Iso2组和Iso3组都按照原来的趋势递增。结论异氟烷在一定时期内可以影响幼龄小鼠的生长发育趋势。     

Effect of diesel exhaust particles and their components on the allergen-specific IgE and IgG1 response in mice

Increased antigen-specific IgE expression is a hallmark of the allergic response in mice. IgG1 may also be involved. Co-injection of mice with diesel exhaust particles (DEP) and ovalbumin three times over a 2 week period lead to a rapid and marked elevation of ovalbumin-specific IgE, IgG1 and also IgG2a, compared with ovalbumin alone. When DEP were injected 1 day before or after ovalbumin on each occasion, their adjuvant effect was considerably muted, suggesting that the adjuvant effect of DEP is short-lived, or that a physical interaction between ovalbumin and DEP is required. DEP were extracted with methylene chloride. Both the resulting core carbon particles and the organic extract enhanced ovalbumin specific IgE and IgG1 levels. Thus the adjuvant effect of DEP in this model is due both to the physical and the chemical attributes of the particles. The tricyclic hydrocarbons phenanthene (the most prevalent polycyclic aromatic hydrocarbon in DEP) and anthracene were both capable of enhancing antigen-specific IgE and IgG1 production. The phenolic antioxidant, butylated hydroxyanisole, which can affect gene expression via the antioxidant responsive element (ARE), had a lesser effect. Two agonists for the aryl hydrocarbon receptor, 3-methychloranthrene and 2,3,7,8-tetrachlorodibenzo-p-dioxin, either were without effect or suppressed the response, suggesting that DEP adjuvancy may not be mediated by this receptor.     

Diesel exhaust particle-induced cell death of human leukemic promyelocytic cells HL-60 and their variant cells HL-NR6

The cytotoxicity of diesel exhaust particles (DEPs) toward human leukemic promyelocytic cells HL-60 was examined. DEPs were toxic and cytotoxicity increased in a dose-dependent manner. All cells died with 750 microg/ml DEPs in culture media. Apoptosis occurred in HL-60 cells exposed to DEPs. The cytotoxicity of DEP extracts with organic solvents was much lower than those of DEPs and organic solvent-washed residual DEPs. HL-NR6 cells, an HL-60 variant cell line, having higher superoxide dismutase and catalase activities than HL-60 cells, were more resistant to DEP cytotoxicity. When preincubated with the fluorescent probe diacetoxymethyl 6-carboxy-2',7'-dichlorodihydrofluorescinate diacetate and then exposed to DEPs, HL-60 cells emitted green fluorescence under blue illumination, indicating that reactive oxygen species were generated within the cells. The DEP cytotoxicity correlated inversely with the cellular concentration of reduced glutathione (GSH), which had been attenuated with L-buthionine-(R,S)-sulfoximine, a gamma-glutamylcysteine synthetase inhibitor, and was lowered with ethyl reduced glutathionate, a GSH carrier across biomembranes. Further, DEPs themselves decreased the cellular concentration of GSH in a dose-dependent manner. The alpha-tocopherol model compound 2,2,5,7,8-pentamethylchroman-6-ol decreased DEP cytotoxicity, while alpha-tocopherol had no effect. In addition, quinacrine, an endocytosis inhibitor, decreased DEP cytotoxicity. These results show that DEPs are cytotoxic and suggest that the cytotoxicity results from generation of reactive oxygen species by DEPs which have been incorporated into cells.     

Diesel exhaust particulates affect cell signaling,mucin profiles,and apoptosis in trachea explants of Balb/C mice

Particulate matter from diesel exhaust (DEP) has toxic properties and can activate intracellular signaling pathways and induce metabolic changes. This study was conducted to evaluate the activation of extracellular signal‐regulated kinase (ERK) and c‐Jun N‐terminal kinase (JNK) and to analyze the mucin profile (acid (AB⁺), neutral (PAS⁺), or mixed (AB/PAS⁺) mucus) and vacuolization (V) of tracheal explants after treatment with 50 or 100 μg/mL DEP for 30 or 60 min. Western blot analyses showed small increases in ERK1/2 and JNK phosphorylation after 30 min of 100 μg/mL DEP treatment compared with the control. An increase in JNK phosphorylation was observed after 60 min of treatment with 50 μg/mL DEP compared with the control. We did not observe any change in the level of ERK1/2 phosphorylation after treatment with 50 μg/mL DEP. Other groups of tracheas were subjected to histological sectioning and stained with periodic acid‐Schiff (PAS) reagent and Alcian Blue (AB). The stained tissue sections were then subjected to morphometric analysis. The results obtained were compared using ANOVA. Treatment with 50 μg/mL DEP for 30 min or 60 min showed a significant increase (p < 0.001) in the amount of acid mucus, a reduction in neutral mucus, a significant reduction in mixed mucus, and greater vacuolization. Our results suggest that compounds found in DEPs are able to activate acid mucus production and enhance vacuolization and cell signaling pathways, which can lead to airway diseases. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1297–1308, 2015.     

Diesel exhaust particles in blood trigger systemic and pulmonary morphological alterations

Short-term exposure to elevated levels of particulate matter is associated with increased respiratory and cardiovascular mortality and morbidity. However, the mechanisms underlying these effects are still unclear. Recent studies have suggested that inhaled ultrafine particles are able to translocate into the bloodstream. To gain more insight into this potential mechanism, we studied the effect of diesel exhaust particles (DEP, 0.02 and 0.1mg/kg), 48h following their intravenous administration, on systemic inflammation and both pulmonary and cardiac morphological alterations in rats. The intravenous administration of DEP (0.1mg/kg) triggered systemic inflammation characterized by an increase of monocyte and granulocyte numbers. Both doses of DEP caused a reduction of the number of red blood cells (RBC) and haemoglobin concentration. Transmission electron microscopy analysis of RBC after in vitro incubation (5microg/ml) or in vivo administration of DEP, revealed the presence of ultrafine-sized aggregates of DEP within the RBC. Larger aggregates were also taken up by the RBC. Moreover, while the myocardial morphology and capillary bed were not affected by DEP exposure, the lungs of rats exposed to DEP (0.02 and 0.1mg/kg) showed clear evidence of inflammation, characterized by neutrophils infiltration. Stereological analysis revealed an increase in interalveolar wall thickness and a decrease in numbers of alveolar sacs per unit area of lung parenchyma of rat exposed to DEP. We conclude that 48h after their systemic administration, DEP cause systemic and pulmonary morphological alterations.     

Dietary exposure to diesel exhaust particles and oxidatively damaged DNA in young oxoguanine DNA glycosylase 1 deficient mice

Pulmonary exposure to diesel exhaust particles (DEP) has been associated with high levels of oxidized DNA in lung cells, whereas long-term oral DEP exposure appears to induce the DNA repair system with concomitant unaltered levels of oxidized DNA in the colon and liver of rats. Here we studied the generation of oxidatively damaged DNA in young wild type (WT) and oxoguanine DNA glycosylase 1 (OGG1) deficient mice after dietary exposure to 0mg/kg, 0.8 mg/kg, or 8 mg/kg Standard Reference Material 1650 in the feed for 21 days. The ingestion of DEP did not increase the levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine and comet assay endpoints in terms of strand break, endonuclease III, and formamidopyrimidine glycosylase (FPG) in the colon, liver, and lung tissue of WT or Ogg1(-/-) mice. The level of OGG1 mRNA could only be measured in WT mice and it was not increased by DEP feeding. On the contrary, the level of FPG sites was twofold higher in the liver and lung of Ogg1(-/-) mice compared to the levels in the WT mice tissues. In conclusion, although Ogg1(-/-) mice have high levels of oxidized guanine lesions, they do not appear to be markedly vulnerable to the genotoxicity by oral administration of DEP.     

The distribution of saponins in vivo affects their synergy with chimeric toxins against tumours expressing human epidermal growth factor receptors in mice

Background and purpose:

Certain saponins synergize with antitumour drugs to enhance their efficacy, but the mechanisms underlying this synergy in vivo are not well studied. Here, we describe the distribution of Saponinum album (Spn) from Gypsophila paniculata L. in mice after subcutaneous injection.

Experimental approach:

The [³H]-labelled Spn used for in vivo experiments was biologically active, as it still increased the cytotoxicity of a chimeric toxin in vitro. Distribution of [³H]-Spn was measured in BALB/c mice, with or without subcutaneous tumours in the flank. Labelled Spn was subcutaneously injected in the neck, and samples of organs, blood, urine and tumour tissue were analysed for radioactivity, 5–240 min after the injection.

Key results:

The majority of [³H]-Spn distributed within 10 min throughout the entire animal, with high levels of radioactivity in the urine by 30 min. No preferential accumulation in tumour tissue or other organs was observed. In tumour-bearing mice, using a sequential combination of Spn (given first) and a chimeric toxin against the epidermal growth factor receptor, ErbB1, we tested two different pretreatment times for Spn. There was high antitumour efficacy (66% inhibition of tumour growth) after 60 min pre treatment with Spn, but no significant inhibition after 10 min pre treatment with Spn.

Conclusions and implications:

[³H]-Spn was rapidly cleared from the mice after s.c. injection, and antitumour synergy with chimeric toxins was correlated with the removal of excess Spn from tissues. Disposition of Spn in vivo may critically determine antitumour synergy with chimeric toxins.     

Inhibition of growth in young mice treated with d,l-methadone

Neonatal mice were treated with d,l-methadone, 1-α-acetylmethadol (LAAM) or the narcotic antagonists, naloxone, nalorphine or levallorphan. Litter mates were injected with normaal saline solution and handled in the same way. Treatment began on the second postpartum day and continued daily or on alternate days for up to 6 weeks. Injection of methadone in dosages of 2 mg/kg to 8 mg/kg inhibited weight gain in a log dose-related fashion. LAAM, 1 mg/kg or 2 mg/kg also retarded weight gain. Mice gained weight normally when naloxone, 10 mg/kg was injected with methadone, 2 mg/kg. Furthermore the daily injection of d-methadone, 4 mg/kg, did not inhibit weight gain nor did any of the narcotic antagonists. There findings indicate that growth inhibition induced by methadone is a stereospecific, opioid effect.     

高龄孕产妇妊娠及分娩临床分析

目的 分析高龄孕产妇妊娠及分娩风险,探讨适宜干预措施.方法 采用回顾性研究的方法,将本院2016年1至6月收治的113例年龄≥35岁的高龄孕产妇纳入研究作为研究组,同时随机选取同期年龄＜ 34岁的113例非高龄孕产妇作为对照组,比较两组孕产妇妊娠及分娩的并发症发生情况、分娩及围产儿结局.结果 研究组妊娠期糖尿病、妊娠期高血压、前置胎盘、胎盘早剥、原发性高血压、糖尿病等发生率明显高于对照组,差异具有统计学意义(均P＜0.05);剖宫产率明显高于对照组(39.82％比24.78％),差异具有统计学意义(P＜0.05);研究组早产、新生儿并发症发生率明显高于对照组,差异具有统计学意义(P＜0.05).结论 高龄孕产妇妊娠并发症及合并症的发生率均升高,剖宫产率随之升高,新生儿并发症升高,故要注意产前保健,并积极提示高龄备孕妇女孕前进行妊娠风险评估,制定个性化孕期及分娩管理,以确保母婴安全.     

Blood lead and zinc in pregnant women and their offspring in intrauterine growth retardation cases

As part of our program to investigate the possible role of environmental pollutants in the incidence of intrauterine-growth retardation (IUGR) in India, we determined the lead and zinc levels in mothers and neonatal blood, collected at parturition, in cases with normal and IUGR babies. Both maternal and cord blood lead levels were significantly higher in IUGR cases than in normal cases (p < 0.05). The mean level of zinc was also higher in maternal blood of IUGR cases. Significantly, the mean cord blood lead level was > 10 microg/dL, which is greater than Centers for Disease Control's intervention level, in 54% of newborns. A good correlation (r = 0.53, p < 0.01) between maternal and cord blood lead levels confirmed the transfer of lead from mother to the fetus. There was a weak but significant relationhsip between cord blood lead levels and birth weight of newborns (r = -0.22, p < 0.05). The study may serve as a pointer to the perils of in utero exposure to chemical contaminants and a call for measures by the public health authorities for a continuous bio-monitoring program to evaluate impact of environmental pollutants on women and children's health.     

Effect of orally administered neomycin on uterine growth in young mice and rats

Neomycin has been widely used as a gut antibiotic in preconditioning animals for the experimental evaluation of biomaterials and biomedical devices. As a chance observation during a routine conditioning process, it was noticed that orally administered neomycin retarded uterine growth in growing mice and rats. Body weights and the weights of liver and spleen were uneffected, although there was a marginal increase in the kidneys' weight. This finding is consistent with the theory that a change induced in intestinal flora activity mediated a uterotrophic influence of dietary fiber.     

青蒿琥酯诱发的自由基对孕鼠与胎鼠造血细胞的毒性

采用妊娠d 13-14 AMS小鼠骨髓和胎肝细胞微核和染色体畸变分析的联合试验方法观察青蒿琥酯对造血细胞的毒性, 并用电子自旋共振技术测定孕鼠和胚胎肝内自由基. 结果表明, 青蒿琥酯不但能诱发孕鼠骨髓细胞微核, 抑制骨髓造血, 而且能通过胎盘屏障损伤胎肝有核细胞. 但未发现对孕鼠骨髓和胎肝细胞的致染色体畸变作用. 青蒿琥酯给药能诱发孕鼠肝和胎肝内自由基信号增强. 本结果提示, 青蒿琥酯诱发经胎盘转运造血母细胞核质损伤和造血抑制可能与药物在体内形成的自由基有关.