N-acetylcysteine and zinc sulphate abate di-2-ethylhexyl phthalate-mediated reproductive dysfunction in rats:Focus on oxidative and sex hormone receptors mechanisms

Objective:To investigate the potential of N-acetylcysteine(NAC)and zinc sulphate(ZnSO_(4))in mitigating reproductive dysfunction caused by di-2-ethylhexyl phthalate(DEHP)in rats and to understand the underlying mechanisms,specifically oxidative stress and sex hormone receptor activity.Methods:Thirty-five male Wistar rats were randomly divided into five equal groups(n=7 per group).Group 1 was administered 0.5 mL of distilled water and served as the control group.Group 2 was given only DEHP(750 mg/kg/day),while group 3,4 and 5 were given DEHP(750 mg/kg/day)plus NAC(100 mg/kg/day),DEHP(750 mg/kg/day)plus ZnSO_(4)(0.5 mg/kg/day),and DEHP(750 mg/kg/day)plus NAC(100 mg/kg/day)as well as ZnSO_(4)(0.5 mg/kg/day),respectively.All treatments lasted for 21 days.Samples were obtained after the rats were sacrificed,and hormones levels in the serum and markers of oxidative stress in the testicles were analyzed using the enzyme-linked immunosorbent assay.The amount of androgen receptors in the testicles was determined by immunohistochemistry,and the susceptibility of testosterone and DEHP to bind to androgen receptor and 5α-reductase was determined by molecular docking studies.Results:DEHP decreased reproductive hormones,testicular antioxidant enzymes,increased malondialdehyde levels,and negatively impacted histology of the pituitary and testes.NAC or ZnSO_(4) treatment showed a marked improvement in testicular antioxidant status and hormone levels,as well as a positive effect on the histology of the pituitary and testes.The combination of both treatments appeared to be more effective.The affinity of DEHP to bind to androgen receptors may lead to disruption of androgen receptor signaling,which can further result in dysfunction of hormones related to androgen.However,NAC is more likely to form stronger binding interactions with follicle stimulating hormone and luteinizing hormone receptors,as well as gonadotropin-releasing hormone receptors,when compared to DEHP.Conclusions:The possibility that NAC and ZnSO_(4) could downregulate DEHP-induced sex hormone changes is suggested by their potential to reduce toxicity.

Green tea polyphenols alleviate di-(2-ethylhexyl)phthalate-induced liver injury in mice

BACKGROUND Di(2-ethylhexyl)phthalate(DEHP)is a common plasticizer known to cause liver injury.Green tea is reported to exert therapeutic effects on heavy metal exposureinduced organ damage.However,limited studies have examined the therapeutic effects of green tea polyphenols(GTPs)on DEHP-induced liver damage.AIM To evaluate the molecular mechanism underlying the therapeutic effects of GTPs on DEHP-induced liver damage.METHODS C57BL/6J mice were divided into the following five groups:Control,model[DEHP(1500 mg/kg bodyweight)],treatment[DEHP(1500 mg/kg bodyweight)+GTP(70 mg/kg bodyweight),oil,and GTP(70 mg/kg bodyweight)]groups.After 8 wk,the liver function,blood lipid profile,and liver histopathology were examined.Differentially expressed micro RNAs(miRNAs)and mRNAs in the liver tissues were examined using high-throughput sequencing.Additionally,functional enrichment analysis and immune infiltration prediction were performed.The miRNA-mRNA regulatory axis was elucidated using the starBase database.Protein expression was evaluated using immunohistochemistry.RESULTS GTPs alleviated DHEP-induced liver dysfunction,blood lipid dysregulation,fatty liver disease,liver fibrosis,and mitochondrial and endoplasmic reticulum lesions in mice.The infiltration of macrophages,mast cells,and natural killer cells varied between the model and treatment groups.mmu-miR-141-3p(a differentially expressed miRNA),Zcchc24(a differentially expressed mRNA),and Zcchc24(a differentially expressed protein)constituted the miRNA-mRNA-protein regulatory axis involved in mediating the therapeutic effects of GTPs on DEHP-induced liver damage in mice.CONCLUSION This study demonstrated that GTPs mitigate DEHP-induced liver dysfunction,blood lipid dysregulation,fatty liver disease,and partial liver fibrosis,and regulate immune cell infiltration.Additionally,an important miRNAmRNA-protein molecular regulatory axis involved in mediating the therapeutic effects of GTPs on DEHP-induced liver damage was elucidated.

Glycerin Monostearate Aggravates Male Reproductive Toxicity Caused by Di(2-ethylhexyl)Phthalate in Rats

Human beings are increasingly exposed to phthalates,which are a group of chemicals used to make plastics more flexible and harder to break,and simultaneously ingesting abundant food emulsifiers via daily diet.The purpose of this study was to investigate the effect of the food emulsifier glycerin monostearate(GMS)on male reproductive toxicity caused by di(2-ethylhexyl)phthalate(DEHP,one of the phthalates)and explore the underlying mechanism.Thirty male Sprague-Dawley rats were randomly divided into control group,DEHP group and DEHP+GMS group.Rats in the DEHP group and DEHP+GMS group were orally administered with 200 mg/kg/d DEHP with or without 20 mg/kg/d GMS.After 30 days of continuous intervention,it was found that the serum testosterone level was significantly lowered in DEHP group and DEHP+GMS group than that in control group(P<0.01).The serum testosterone level and the relative testis weight were significantly decreased in the DEHP+GMS group as compared with those in the DEHP group and control group(P<0.05).More spermatids were observed to be shed off in DEHP+GMS group than in DEHP group.The expression levels of cell cycle checkpoint kinase 1(Chkl),cell division cycle gene 2(Cdc2),and cyclin-dependent kinase 2(CDK2)were down-regulated in DEHP group,and this tendency was more significant in DEHP+GMS group(P<0.05 or P<0.01).There was no significant difference in the P-glycoprotein(P-gp)expression between DEHP group and control group.However,P-gp was markedly down-regulated in DEHP+GMS group(P<O.Ol).The results indicated that the food emulsifier GMS aggravated the toxicity of DEHP on male reproduction by inhibiting the cell cycle of testicular cells and the expression of P-gp in testis tissues.

Urine Metabonomic Analysis of Interventions Effect of Soy Isoflavones on Rats Exposed to Di-(2-ethylhexyl) Phthalate

Objective Di-(2-ethylhexyl) phthalate(DEHP) is a ubiquitous environmental contaminant.As an endocrine disruptor,it seriously threatens human health and ecological environmental safety.This study examines the impact of intervention with soybean isoflavones(SIF) on DEHP-induced toxicity using a metabonomics approach.Methods Rats were randomly divided into control(H),SIF-treated(A,86 mg/kg body weight),DEHP-treated(B,68 mg/kg),and SIF plus DEHP-treated(D) groups.Rats were given SIF and DEHP daily through diet and gavage,respectively.After 30 d of treatment,rat urine was tested using UPLC/MS with multivariate analysis.Metabolic changes were also evaluated using biochemical assays.Results Metabolomics analyses revealed that p-cresol glucuronide,methyl hippuric acid,N1-methyl-2-pyridone-5-carboxamide,lysophosphatidycholine [18:2(9 Z,12 Z)] {lyso PC [18:2(9 Z,12 Z)]},lyso PC(16:0),xanthosine,undecanedioic acid,and N6-acetyl-l-lysine were present at significantly different levels in control and treatment groups.Conclusion SIF supplementation partially protects rats from DEHP-induced metabolic abnormalities by regulating fatty acid metabolism,antioxidant defense system,amino acid metabolism,and is also involved in the protection of mitochondria.

Impairment of Di(2-Ethylhexyl) Phthalate on Cellular Immunity in Kunming Mice

Immunity is crucial to the health of animals and it can determine their survival and fitness. Di(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer and hence is the most abundant phthalate in the environment. Exposure to DEHP is of great concern for human health. In the present study, we tested the hypothesis that exposure to DEHP would suppress T cell-mediated immunity in mice. Twenty adult male Kunming mice were randomly assigned into the control (n = 10) and the DEHP treatment (n = 10) groups. Both groups have free access to food and water, while the mice in the latter group drank DEHP solution (2000 mg/L) for 42 days. T cell-mediated immunity assessed by phytohaemagglutinin (PHA) response was depressed in the DEHP treated mice compared with the controls, however, wet thymus and spleen mass, white blood cells were not influenced by DEHP treatment. Taken together, different immunological parameters responded differently to DEHP treatment in Kunming mice.

An Estimation of the Daily Intake of Di(2-ethlhexyl) Phthalate(DEHP) among Workers in Flavoring Factories

Objective To estimate the daily intake of DEHP among workers in flavoring factories. Methods 71 workers in two flavoring manufacturers, 27 administrators in those factories and 31 laboratory technicians in a research institute were recruited and assigned to exposure group, control group 1 and control group 2 respectively. Their urinary DEHP metabolites, mono（2-ethylhexyl） phthalate （MEHP）, mono-（2-ethyl-5-hydroxyhexyl） phthalate （MEHHP）, mono-（2-ethyl-5-oxohexyl） phthalate （MEOHP）, were detected by isotope dilution-ultra performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS）. The urinary metabolites concentrations were converted into DEHP intake levels using two pharmacokinetic models： the urine creatinine-excretion （UCE） one and the urine volume （UV） one. Results No significant differences were found among the three groups. Based on the urinary concentrations of Z3MEHP, we got a median daily DEHP intake of 3.22 or 1.85 μg/kg body-weight/day applying the UV or UCE models respectively. Depending on the UV model, three subjects （2.34%） exceeded the RfD value given by US EPA and the P50 of estimate daily DEHP intakes accounted for 16.10% of the RfD value. No subjects exceeded the limitation depending on the UCE model. Conclusion The workers in flavoring factories were not supposed to be the high DEHP exposure ones and their exposure level remained at a low risk.

Aquatic toxicity of di (2-eihylhexyl) phthalate to duckweeds

This study is concerned with the effects of di （2-ethylhexyl） phthalate （DEHP） on two kinds of duckweeds （Spirodela polyrhiza and Lemna minor）.The results indicate that DEHP has aquatic toxicity to Spirodela polyrhiza at 0.4 mg/L and to Lemna minor at over 0.1 mg/L by changing their physiologic-biochemical characteristics.The contents of duckweed chlorophyll and soluble protein decrease with increasing DEHP concentration after 7 d of exposure.DEHP shows the stimulating role in catalase （CAT） and superoxide dismutase （SOD） systems at relative low levels.At 0.01 mg/L and 0.005 mg/L,SOD activities of Spirodela polyrhiza and Lemna minor reach their peak values respectively,while CAT activity reaches its maximum value at 0.05 mg/L and 0.01 mg/L.When DEHP levels are too high,the protection enzyme system would be destroyed and plant growth is inhibited.The analysis of malondialdehyde （MDA） and Fourier transform infrared spectroscopy manifest that DEHP could affect the tested duckweeds by destroying its cell membranes,and Spirodela polyrhiza is more resistant to DEHP exposure than Lemna minor.

Intensified reactive extraction of 4-hydroxypyridine with di(2-ethylhexyl) phosphoric acid in 1-octanol by using tributyl phosphate

The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent.

Reducing children’s exposure to di(2-ethylhexyl)phthalate in homes and kindergartens in China:Impact on lifetime cancer risks and burden of disease

Exposure to di(2-ethylhexyl)phthalate(DEHP)in the indoor environment has been linked with significant health risks for Chinese children.Multi-phase DEHP concentrations in Chinese residences and kindergartens were estimated using a mass balance model based on the current baseline condition and control strategies(i.e.,increasing ventilation rate,reducing area of sources,using mechanical ventilation systems,and using portable air cleaners).The health benefits of each control strategy were quantified as the reduction in lifetime cancer risks(LCR)and burden of disease(BoD).In the current situation,the mean LCR and disability-adjusted life years(DALY)number attributable to indoor DEHP exposure for Chinese children were around 6.0×10^(−6) and 155 thousand,respectively.The mean LCR and DALY might be reduced by 25%-54%and 16%-40%,respectively,by increasing air exchange rates by 100%,reducing the use of source materials by two-thirds or deploying commercial air cleaners in naturally ventilated buildings.Meanwhile,avoidable DALYs could result in a reduction of mean economic losses of 2.2-5.3 billion RMB.Mechanical ventilation systems with filtration units may not be helpful for reducing children’s health risks.House-specific and tailor-made control measures are critical in lowering indoor exposure to DEHP to promote sustainable buildings and children’s health in China.

Maslinic acid supplementation prevents di(2-ethylhexyl)phthalate-induced apoptosis via PRDX6 in peritubular myoid cells of Chinese forest musk deer

Chinese forest musk deer(FMD),an endangered species,have exhibited low reproductive rates even in captivity due to stress conditions.Investigation revealed the presence of di(2-ethylhexyl)phthalate(DEHP),an environmental endocrine disruptor,in the serum and skin of captive FMDs.Feeding FMDs with maslinic acid(MA)has been observed to alleviate the stress response and improve reproductive rates,although the precise molecular mechanisms remain unclear.Therefore,this study aims to investigate the molecular mechanisms underlying the alleviation of DEHP-induced oxidative stress and cell apoptosis in primary peritubular myoid cells(PMCs)through MA intake.Primary PMCs were isolated and exposed to DEHP in vitro.The results demonstrated that DEHP significantly suppressed antioxidant levels and promoted cell apoptosis in primary PMCs.Moreover,interfering with the expression of PRDX6 was found to induce excessive reactive oxygen species(ROS)production and cell apoptosis in primary PMCs.Supplementation with MA significantly upregulated the expression of PRDX6,thereby attenuating DEHP-induced oxidative stress and cell apoptosis in primary PMCs.These findings provide a theoretical foundation for mitigating stress levels and enhancing reproductive capacity of in captive FMDs.

邻苯二甲酸二(2-乙基己基)酯致人脐静脉内皮细胞氧化损伤及白藜芦醇的修复作用

目的:探究邻苯二甲酸二(2-乙基己基)酯(di-2-ethylhexyl phthalate,DEHP)诱导的人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVEC)的氧化损伤,以及白藜芦醇对该损伤的修复作用。方法:通过CCK8实验筛选DEHP的损伤浓度和白藜芦醇的修复浓度;化学分光光度比色法检测HUVEC丙二醛和超氧化物歧化酶(SOD)的不同表达情况;活性氧荧光探针检测不同处理组HUVEC内活性氧水平;JC-1试剂盒检测不同组HUVEC线粒体膜电位;CCK8实验、Transwell实验、划痕愈合实验观察HUVEC增殖、迁移能力;细胞流式实验、蛋白质印迹实验观察HUVEC的凋亡情况和凋亡相关蛋白的表达。结果:80μmol/L DEHP作用HUVEC 24 h后,细胞增殖能力明显降低(P<0.01),40μmol/L白藜芦醇对细胞无明显毒性;损伤组细胞的丙二醛水平和SOD活性较对照组均明显上升(P均<0.01),修复组丙二醛水平和SOD活性较损伤组均明显下降(P均<0.05);损伤组细胞的活性氧表达较对照组明显上升(P<0.01),修复组较损伤组明显下降(P<0.01);损伤组细胞的线粒体膜电位较对照组明显下降(P<0.01),修复组较损伤组明显上升(P<0.01);损伤组细胞的增殖、迁移、成管能力较对照组明显下降(P均<0.05),修复组较损伤组明显上升(P均<0.05);损伤组细胞的凋亡水平较对照组明显上升(P<0.05),修复组较损伤组明显下降(P<0.05)。结论:DEHP能够通过氧化应激途径抑制HUVEC的增殖、迁移和成管能力,并诱导其凋亡,而白藜芦醇可以有效修复该种损伤。

叶酸对邻苯二甲酸二(2-乙基己基)酯(DEHP)暴露导致小鼠胆汁淤积型肝损伤的保护作用

目的探讨叶酸对邻苯二甲酸二(2-乙基己基)酯(DEHP)暴露诱发小鼠胆汁淤积型肝损伤的保护作用及其机制。方法将ICR小鼠随机分为对照(Control)组、叶酸高剂量(H-FA)组、DEHP组、DEHP+叶酸低剂量(DEHP+L-FA)组、DEHP+叶酸高剂量(DEHP+H-FA)组,每组6只。H-FA组、DEHP+L-FA组和DEHP+H-FA组给予相应剂量的叶酸灌胃,Control组和DEHP组灌胃等量的PBS溶液。2 h后,DEHP组、DEHP+L-FA组和DEHP+H-FA组给予含200 mg/kg DEHP的玉米油,Control组和H-FA组灌胃等量的纯玉米油,共灌胃4周。记录小鼠每天的体质量和摄食量,收集血液和肝组织。生化仪检测血清总胆汁酸(TBA)和碱性磷酸酶(ALP)水平;HE染色观察肝组织病理变化;试剂盒检测肝组织丙二醛(MDA)和超氧化物歧化酶(SOD)含量;LC-MS/MS检测小鼠血清胆汁酸谱;Western Blot法检测肝脏胆汁酸代谢相关蛋白的表达水平。计量资料多组间比较采用单因素方差分析,进一步两两比较采用LSD-t检验。结果与对照组相比,DEHP组小鼠每日摄食量明显下降,体质量从第10天开始显著降低(P值均<0.05);与DEHP组相比,DEHP+L-FA组与DEHP+H-FA组小鼠的体质量和摄食量基本不变(P值均>0.05)。与对照组相比,DEHP组小鼠肝质量指数、血清TBA及ALP均显著升高(P值均<0.05),肝组织可见汇管区扩大,胆管变形增生及少量炎性细胞浸润;与DEHP组相比,DEHP+L-FA组与DEHP+H-FA组小鼠肝质量指数均明显下降(P值均<0.01),DEHP+H-FA组的血清TBA和ALP均显著下降(P值均<0.05),叶酸干预后小鼠肝组织形态结构明显改善。与对照组相比,DEHP组小鼠肝脏SOD含量明显下降(P<0.05),肝脏MDA含量明显增加(P<0.01);与DEHP组相比,MDA和SOD含量在DEHP+H-FA组均显著回调(P值均<0.05)。与对照组相比,DEHP组小鼠血清中α-鼠胆酸(α-MCA)、β-鼠胆酸(β-MCA)、去氧胆酸(DCA)、石胆酸(LCA)、牛磺胆酸(TCA)、牛磺去氧胆酸(TDCA)、牛磺熊去氧胆酸(TUDCA)、牛磺-β-鼠胆酸(T-β-MCA)、牛磺-α-鼠胆酸(T-α-MCA)、牛磺猪去氧胆酸(THDCA)、牛磺石胆酸(TLCA)均明显升高(P值均<0.05),熊去氧胆酸(UDCA)明显降低(P<0.05);与DEHP组相比,血清中DCA、LCA、TCA、TDCA、TUDCA、T-β-MCA、T-α-MCA、THDCA、TLCA在DEHP+H-FA组均明显回调(P值均<0.05)。与对照组相比,DEHP组小鼠肝脏FXR和CYP3A11蛋白表达量均明显增加(P值均<0.01),CYP7A1和MRP2蛋白表达量显著降低(P值均<0.01);与DEHP组相比,肝脏FXR和CYP3A11蛋白表达量在DEHP+L-FA组和DEHP+H-FA组中均明显下调(P值均<0.05);MRP2蛋白表达量在DEHP+L-FA组DEHP+H-FA组中均显著上调(P值均<0.05);CYP7A1蛋白表达量在DEHP+H-FA组中显著上调(P<0.05)。结论叶酸对DEHP暴露导致的小鼠胆汁淤积型肝损伤有保护作用,其机制可能是调节胆汁酸合成、代谢与转运从而维持胆汁酸稳态。

邻苯二甲酸二(2-乙基己基)酯(DEHP)诱发小鼠胆汁淤积和肝损伤的作用机制

目的探讨邻苯二甲酸二(2-乙基己基)酯(DEHP)诱发小鼠胆汁淤积和肝损伤机制研究。方法体内实验:将成年雌性ICR小鼠随机分为对照组(玉米油)、DEHP组(200 mg·kg^(−1)·d^(−1)),共灌胃4周,建立胆汁淤积模型。收集所有小鼠血液与肝组织,生化仪检测血清、肝脏总胆汁酸(TBA)水平,酶标仪检测ALP、GGT;HE染色观察肝组织病理变化;实时定量PCR检测肝脏炎症因子IL-1β、IL-6和TNF-α的表达水平;液相色谱-三重四级杆质谱仪(LC-MS/MS)检测小鼠肝脏胆汁酸谱。体外实验:培养小鼠肝细胞AML-12,使用DEHP(250μmol/L)以及去氧胆酸(DCA)(125μmol/L)和鹅去氧胆酸(CDCA)(125μmol/L)处理细胞24 h,实时定量PCR检测细胞炎性因子IL-1β、IL-6和TNF-α的mRNA水平。计量资料两组间比较采用成组t检验,多组间比较采用单因素方差分析,进一步两两比较采用LSD-t检验。结果体内实验显示:与对照组相比,DEHP组小鼠肝体比,血清TBA、ALP、GGT及肝脏TBA均显著升高(t值分别为−4.396、−5.109、−8.504、−3.792和−7.974,P值均<0.05)。与对照组相比,肝脏胆汁酸谱中胆酸(CA)、CDCA、牛磺鹅去氧胆酸(TCDCA)、DCA及熊去氧胆酸(UDCA)均显著升高(t值分别为−2.802、−3.177、−2.633、−2.874和−2.311,P值均<0.05)。DEHP组小鼠肝脏HE染色显示为汇管区扩大、胆管变形、胆管周围伴有炎性细胞浸润,且肝脏炎症因子IL-1β、IL-6和TNF-αmRNA水平均显著升高(t值分别为−2.539、−2.823和−4.636,P值均<0.05)。体外实验显示:0~1000μmol/L DEHP处理后肝细胞活力实际数值相差不超过15%,分别使用125、250以及500μmol/L的DEHP刺激后,肝细胞的炎症因子IL-1β、IL-6和TNF-αmRNA水平均明显升高(P值均<0.05)。与单独使用DEHP刺激相比,CDCA联合DEHP刺激上调了细胞炎症因子IL-1βmRNA水平(P<0.01);DCA与DEHP联合刺激可显著增加细胞炎症因子IL-1β和IL-6的mRNA水平(P值均<0.01)。结论DEHP暴露导致小鼠胆汁淤积肝病的发生并诱发肝脏炎症,这可能与其促进有毒胆汁酸的产生进而加剧炎性因子分泌有关。

吉林省某医院成年人尿中邻苯二甲酸二(2-乙基己基)酯的暴露水平及其影响因素

目的评估成年人尿中邻苯二甲酸二(2-乙基己基)酯[di(2-ethylhexyl)phthalate,DEHP]代谢物水平及其影响因素。方法2022年3月本研究纳入吉林省某医院210名成年人,采集晨尿样并通过高效液相色谱串联质谱法测定尿液中5种DEHP代谢物(MEHP、MEOHP、MEHHP、MCMHP和MECPP)的水平。通过Spearman秩相关分析研究对象尿液中DEHP代谢产物浓度之间的关系,采用独立样本t检验比较每种变量不同项目间DEHP代谢产物水平的差异,使用多元线性回归模型分析所选因素与研究对象尿液中DEHP代谢产物水平之间的关系。结果MEHP和MEOHP检出率分别为98.6%和99.5%,MEHHP、MCMHP和MECPP的检出率均为100.0%。MCMHP的中位数浓度最高,为14.45μg/L(14.10μg/g肌酐)。在调整协变量后,主动吸烟与尿液MEOHP(β=-0.151,95%CI:-0.299~-0.004)显著相关;被动吸烟与MCMHP(β=-0.184,95%CI:-0.323~-0.045)、MECPP(β=-0.192,95%CI:-0.332~-0.051)和∑DEHP(β=-0.146,95%CI:-0.291~-0.001)显著相关;塑料水杯的使用与MEHHP(β=-0.147,95%CI:-0.284~-0.009)显著相关;护肤类化妆品的使用频率与MEOHP(β=-0.115,95%CI:-0.297~-0.012)和MEHHP(β=-0.194,95%CI:-0.337~-0.051)显著相关。结论本研究中成年人广泛暴露于DEHP,日常生活中不吸烟及远离二手烟、减少塑料水杯和护肤类化妆品的使用可降低DEHP的暴露水平。

邻苯二甲酸二(2-乙基己基)酯对睾丸的毒性作用及机制

邻苯二甲酸二(2-乙基己基)酯(DEHP)是目前使用最广泛的增塑剂之一,DEHP具有毒性,长期暴露会对机体的多个系统产生损害,特别是对雄性生殖系统的毒性作用更为明显。DEHP通过诱导氧化应激、调控细胞自噬,促进生精细胞和睾丸间质细胞凋亡、抑制睾酮合成、破坏血-睾屏障、诱导睾丸支持细胞铁死亡以及影响子代雄性的表观遗传等,造成生殖器官的病理损伤。本文就DEHP对睾丸的毒性作用及机制进行综述,拟为男性生殖障碍的防治研究提供新思路。

Structure Reactivity Studies on the Extraction of Rare Earths by Di(2-ethylhexyl)chloroalkyl Phosphonates

The extractive separation properties and the extractive regularity of the lanthanide elements by five di(2-ethylhexyl)alkyl phosphonates with various alkyl structure:di(2-ethylhexyl)chloromethyl phosphonate CH_2ClP(O) (OC_8H_(17)-i)_2(1),di(2-ethylhexyl)β-chloroethyl phosphonate ClCH_2CH_2P(O) (OC_8H_(17)-i)_2 (2),di(2-ethylhexyl)α-chloroethyl phosphonate CH_3CHClP(O)(OC_8H_(17)-i)_2 (3),and corresponding di(2-ethylhexyl)methyl phosphonate CH_3P(O)(OC_8H_(17)-i)_2 (4),di(2-ethylhexyl)ethyl phosphonate C_2H_5P(O) (OC_8H_(17)-i)_2 (5),in nitrate system have been studied.The coordination compounds were prepared. The structure of these extractants and their coordination compounds were further explored by IR and ^(31)P NMR spectra.

蜡样芽孢杆菌对邻苯二甲酸二(2-乙基己基)酯的降解特性研究

选择邻苯二甲酸二(2-乙基己基)酯(DEHP)作为目标污染物,采用实验室前期从九溪人工湿地植物香蒲(Typha Linn)根际土中富集驯化分离的DEHP降解菌X41作为供试菌株,通过对其形态、生理生化特征及16S rDNA序列进行分析,初步鉴定菌株X41为蜡样芽孢杆菌(Bacillus cereus)。采用正交试验研究菌株X41对DEHP最佳降解条件和降解特性。结果表明,菌株X41在pH为6.0,温度为35℃,接菌量为3%,DEHP初始质量浓度为300 mg/L的环境条件下降解效率最高,且在此最优降解条件下,菌株X41生长良好,生长曲线呈“S”型,7 d的DEHP降解率高达99.54%。实验结果可为人工湿地中DEHP的去除提供一定的科学依据。

塑胶中邻苯二甲酸二(2-乙基己基)酯萃取剂及萃取时间的研究

本文通过研究甲苯、正己烷萃取在不同浓度的DEHP提取效率、回收率,针对塑胶制品确定了相对有效的萃取溶剂,同时通过改变超声温度挑选出最有效的超声温度,并用实际样品进行了相关实验验证。结果表明:甲苯萃取剂萃取效率更高(92.4%),超声萃取温度与30℃时效率最高,标液线性良好(R^(2)=0.999 8),回收率在(92.3~95.2)%。

邻苯二甲酸二(2-乙基)己酯对原代培养小鼠胚胎睾丸Leydig细胞功能影响研究

目的探讨邻苯二甲酸二(2-乙基)己酯[D i(2-ethylhexyl)phthalate,DEHP]对体外培养的小鼠胚胎睾丸间质细胞(Leyd ig细胞)3β-羟基类固醇脱氢酶(3-βHSD)活性及睾酮合成的影响。方法小鼠胚胎Leyd ig细胞原代培养。DE-HP染毒剂量分别为25、50、100、200 mg/L,通过检测睾酮合成关键酶3β-HSD活性、放免法测定培养液中睾酮浓度,研究DEHP对Leyd ig细胞功能影响。结果小鼠胚胎Leyd ig细胞分离培养后,纯度和存活率分别达(81.17±2.32)%、(80.88±2.80)%。DEHP(25 mg/L)处理12 h,或DEHP(50 mg/L)处理6 h后,实验组与对照组比较3β-HSD酶活性明显降低(P<0.05),随着时间延长和药物浓度增加差异更显著(P<0.01)。DEHP50、100 mg/L实验组,在12、24 h的睾酮水平明显低于对照组(P<0.05)或(P<0.01),存在时间-效应关系;DEHP 200 mg/L实验组在6、12、24 h与对照组比较均有非常显著差异(P<0.01),并可观察到Leyd ig细胞明显的形态学改变。结论DEHP能影响原代培养小鼠胚胎Leyd ig细胞3β-羟基类固醇脱氢酶活性,并抑制睾酮合成,存在时间-效应和剂量-效应关系。

邻苯二甲酸二(2-乙基)己酯对胚胎及新生小鼠睾丸Leydig细胞INSL3 mRNA表达的影响

目的：通过体内体外实验探讨邻苯二甲酸二（2-乙基）己酯（DEHP）对胚胎及新生小鼠睾丸Leydig细胞INSL3 mRNA表达的影响．方法：DEHP50，100，200mg／L分别作用于原代培养的小鼠胚胎Leydig细胞，应用RT—PCR和原位分子杂交技术检测DEHP对Leydig细胞INSL3 mRNA表达的影响；DEHP分别以低、中、高三组剂量（100，200和500mg／kg·d）灌胃作用于GD（Gestationday）12～PND（Postnatal day）3孕鼠，RT—PCR检测新生小鼠睾丸INSL3 mRNA表达的相对强度．结果：DEHP改变原代培养的小鼠胚胎Leydig细胞和新生小鼠睾丸的形态结构；各实验组包括原代Leydig细胞及不同时间点的新生鼠睾丸INSL3 mRNA表达水平、表达相对强度均明显低于对照组（P〈0．05，或P〈0．01）．结论：DEHP下调小鼠睾丸Leydig细胞INSL3 mRNA的表达，可能是影响引带发育导致隐睾的机制之一．