邻苯二甲酸二乙基己基酯对新生大鼠肺组织发育的影响

目的探讨基质金属蛋白酶9(MMP-9)、金属蛋白酶1组织抑制剂(TIMP-1)和转化生长因子β1(TGF-β1)是否参与邻苯二甲酸二乙基己基酯(DEHP)影响肺组织形态发育的过程。方法 SD新生大鼠于出生后第1天开始分别ip给予DEHP 10,100和750 mg.kg-1,每天1次。每组1/2大鼠持续染毒14 d,剩余1/2大鼠持续染毒21 d。染毒结束后第2天处死大鼠,取新鲜肺组织,提取总RNA,用实时定量PCR方法检测MMP-9,TIMP-1和TGF-β1mRNA的表达;其余部分石蜡包埋,制备石蜡切片,HE染色进行组织形态观察,或者免疫组化染色检测MMP-9,TIMP-1和TGF-β1蛋白表达。结果 DEHP染毒14 d,与溶剂对照组比较,DEHP 100和750 mg.kg-1组新生大鼠肺泡发育受抑制,肺间质比例增大(P<0.05);DEHP10,100和750 mg.kg-1组MMP-9和TGF-β1mRNA表达随着DEHP染毒剂量的增加而增加(r=0.979,P<0.01;r=0.990,P<0.01),MMP-9和TGF-β1蛋白表达亦随着DEHP染毒剂量的增加而增加(r=0.770,P<0.01;r=0.959,P<0.01);TIMP-1 mRNA和蛋白表达下降(r=0.904,P<0.01;r=0.795,P<0.01)。DEHP染毒21 d,DEHP 10,100和750 mg.kg-1组肺间质比例与溶剂对照组比较无明显变化;MMP-9和TGF-β1mRNA表达随着DEHP染毒剂量的增加而下降(r=0.879,P<0.01;r=0.904,P<0.01),MMP-9和TGF-β1蛋白表达亦随着DEHP染毒剂量的增加而下降(r=0.935,P<0.01;r=0.819,P<0.01);TIMP-1 mRNA和蛋白表达增加(r=0.819,P<0.01;r=0.619,P<0.01)。结论 DEHP通过影响肺组织MMP-9,TIMP-1和TGF-β1基因和蛋白的表达影响新生大鼠肺组织形态发育。     

HPLC测定PVC输液袋中的邻苯二甲酸二(2-乙基己基)酯

目的 测定PVC输液袋中增塑剂邻苯二甲酸二(2-乙基己基)酯(DEHP)的含量.方法 采用HPLC法,流动相为甲醇-水(90:10),流速为1.0 ml·min-1,检测波长为222 nm.结果 峰面积与DEHP浓度的线性关系良好(r=0.9999).结论 所用方法简便,结果准确可靠.     

邻苯二甲酸二乙基己酯体内代谢和毒性机制研究进展

塑化剂被广泛用于各种塑料制品当中,其中以邻苯二甲酸二乙基己酯(DEHP)最为典型。随着食品中添加塑化剂的新闻不断被曝光,塑化剂对人体健康的危害逐渐引起大众关注。塑化剂及其体内代谢物在体内的蓄积可导致多个器官的损伤。塑化剂生殖器官蓄积可造成生殖系统明显的损伤,在肝脏累积可导致氧化应激而引发肝细胞凋亡,同时塑化剂又能作为佐剂影响免疫系统。该文将就DEHP的生殖毒性、肝脏毒性和免疫毒性及其有关机制进行了系统阐述。     

邻苯二甲酸二-（2-乙基己基）酯对小鼠胚胎致畸作用和心肌细胞的毒性

邻苯二甲酸酯类被广泛用作增塑剂，在某些塑料产品中，含量甚至高达50％。由于其应用广泛，及易于从塑料中迁移出来，故对环境污染严重。而邻苯二甲酸二-(2-乙基己基)酯(DEHP)的用量占了增塑剂的25％，主要用于食品包装和医用器材等。动物实验表明邻苯二甲酸酯类具有致畸性，亦有资料表明它是内分泌干扰物。     

活性氧在邻苯二甲酸单(2-乙基己基)酯所致心肌细胞DNA损伤中的作用

目的 探讨邻苯二甲酸单(2-乙基己基)酯(MEHP)对人源心肌AC16细胞DNA的损伤作用及其可能机制。方法 以人源心肌AC16细胞为研究对象,分为对照组,40、60、80、100和120μmol/L MEHP组。处理细胞24 h后采用DCFH-DA探针标记测定AC16细胞内活性氧(ROS)水平;单细胞凝胶电泳实验测定细胞DNA损伤情况;利用抗氧化剂N-乙酰-L-半胱氨酸(NAC)抑制AC16细胞内ROS生成,以观察ROS在MEHP所致AC16细胞DNA损伤中的作用。结果 与对照组相比,AC16细胞经MEHP处理后,ROS水平随着MEHP浓度的增加而明显升高(P<0.05);对照组心肌细胞核呈圆形荧光团,强度均匀,边缘光滑,大小较一致,无明显拖尾。不同浓度MEHP处理后,各组心肌细胞出现彗星拖尾现象,且具有MEHP浓度依赖性。与对照组OTM值和TD值相比,MEHP组OTM值和TD值明显升高,且有统计学意义(P<0.05);预先给予NAC可明显降低MEHP所致的细胞ROS水平升高。与相应的MEHP组相比,NAC+MEHP组OTM值及TD值明显降低,且差异有统计学意义(P<...     

邻苯二甲酸二乙基已基酯联合高氧通过调控Akt/GSK-3β信号通路介导细胞凋亡影响新生大鼠肺发育

目的 探讨邻苯二甲酸二乙基己基酯(DEHP)联合高氧对新生大鼠肺发育的影响及其机制。方法新生SD大鼠随机分为4组：正常对照、高氧、DEHP和高氧+DEHP组。正常对照组大鼠置空气环境并每天ig给予玉米油5 mL·kg^-1;DEHP组大鼠出生后每天ig给予DEHP 750 mg·kg^-1;高氧组大鼠出生后12 h内即置氧箱中持续吸入80%～85%O2;高氧+DEHP组大鼠出生后12 h内即置于氧箱中并每天ig给予DEHP750 mg·kg^-1。各组出生后第7天取肺组织,HE染色观察肺组织形态改变,TUNEL染色观察肺上皮细胞凋亡,Western印迹法测定肺组织蛋白激酶B(Akt),糖原合成酶激酶3β(GSK-3β),Bcl-2,Bax和活化胱天蛋白酶3蛋白表达水平。结果 HE染色结果显示,DEHP、高氧及高氧+DEHP组肺泡结构均呈现不同程度简单化和肺泡数量减少的形态改变。TUNEL结果显示,与正常对照组相比,DEHP和高氧组细胞凋亡显著增加(P<0.01);与高氧组相比,高氧+DEHP组细胞凋亡显著增加(P<...     

低剂量邻苯二甲酸二(2-乙基)己酯对老年大鼠前列腺的促增生作用

目的评价环境暴露剂量的邻苯二甲酸二(2-乙基)己酯(DEHP)对老年大鼠前列腺的促增生作用及机制。方法 32只1.5岁龄老年雄性SD大鼠随机分成4组,每组8只,分别ig给予DEHP(30,90和270μg·kg~(-1))或溶媒,每天1次,连续4周。于末次给药24 h后将大鼠麻醉,而后(1)腹主动脉采血,采用ELISA检测血清中睾酮(T)、雌二醇(E2)和泌乳素(PRL)水平;(2)处死后取前列腺,分叶,称重、测量体积,计算脏器系数;(3)制作前列腺组织病理切片,HE染色后用显微镜观察组织形态改变,并利用显微图像分析软件分析前列腺上皮高度变化。结果与溶媒对照组比较,DEHP 270μg·kg~(-1)组前列腺系数、背侧前列腺质量和背侧前列腺系数均显著增加(P<0.05);DEPH各剂量组腹侧前列腺上皮高度明显升高(P<0.01);DEHP 270μg·kg~(-1)组背侧前列腺上皮高度明显升高(P<0.01);DEHP各剂量组E2,PRL和T水平均无显著改变,但DEHP 30和270μg·kg~(-1)组E2/T比值显著增加(P<0.05)。结论低剂量DEHP对老年大鼠前列腺具有促增生作用,该作用可能与其影响内源性激素的相对水平有关。     

蓝氧片对邻苯二甲酸(2-乙基己基)酯致小鼠睾丸超微形态结构损害的保护作用

目的 观察塑化剂邻苯二甲酸(2-乙基己基)酯(DEHP)对小鼠睾丸超微形态结构的影响,并研究蓝氧片(专利药用组合Y523)对小鼠睾丸生精细胞和支持细胞的保护和修复作用及其机制。方法 55只成年♂小鼠随机分为DEHP组、Y523组和对照组。DEHP组以大豆油为溶剂,剂量分别为：0,10,20,50,和100 mg·kg^-1·d^-1,连续30 d灌胃染毒;Y523组以等量大豆油混合1 000 mg蓝氧片原料粉剂连续30 d灌胃给药后重复DEHP组的灌胃染毒过程;对照组以标准饲料同期喂养。采用透射电镜观察小鼠睾丸超微结构的改变。结果 与对照组相比,随着DEHP灌胃染毒剂量的递增,DEHP组小鼠睾丸生精细胞出现胞膜塌陷,核质疏松,小细胞器消失,空泡形成,甚至整个生精细胞层消失;支持细胞胞膜皱缩,核质浓缩,胞质内空泡形成和凋亡小体样结构。与DEHP组相比,蓝氧片组小鼠睾丸生精细胞和支持细胞的超微形态结构改变与对应剂量DEHP灌胃染毒的DEHP组小鼠基本类似,但胞质内线粒体、溶酶体等小细胞器的数量明显增多。结论 DEHP灌胃染毒可致小鼠睾丸生精细胞空泡样变性退化,细胞胀亡和凋亡。蓝氧片对DEHP所致的睾丸损害有一定的保护作用,其机制可能与小鼠睾丸支持细胞内线粒体和溶酶体等细胞器数量的增加有关。     

新生儿静脉营养液中邻苯二甲酸二(2-乙基)己酯含量检测

目的建立气相色谱-质谱联用(GC-MS)法测定新生儿静脉营养液中邻苯二甲酸二(2-乙基)己酯(DEHP)的含量。方法收集放置不同时间段的新生儿静脉营养液,采用GC-MS进行定性定量,考察其DEHP的含量及其变化。结果新生儿静脉营养液中DEHP量随软袋放置时间延长而增加,测得放置24 h DEHP为3.23 mg·L-1。结论新生儿静脉营养液中放置24 h,溶出的DEHP量低于新生儿耐受摄入量,但也对新生儿带来危害。     

Teratogenicity of di-(2-ethylhexyl)phthalate in mice

Fetotoxicity of di-(2-ethylhexyl)phthalate (DEHP) was studied in a random strain (ddY-Slc♀ × CBA ♂) of mice. A single oral administration of DEHP 0.05 ml/kg on day 7 of gestation resulted in a decrease in body weight of live fetuses, but there were no dead, gross, or skeletal abnormal fetuses. At 0.1 ml/kg and above DEHP decreased fetal body weight and the fetuses were dead or deformed. The fetotoxicity was dose dependent and a straight line Y = 51.9 log X + 61.6 was obtained where Y = the rate of death(%) and X = the dose of DEHP administered (ml/kg). The LD₅₀ and the non-effective aximum dose which induced fetal death was 0.60 ml/kg and 0.065 ml/kg, respectively. The non-effective maximum doses which resulted in gross and skeletal abnormalities were 0.80 and 0.68 ml/kg, respectively.     

Studies on the effects of orally administered di-(2-ethylhexyl) phthalate in the ferret

A target-organ study of the effects of the phthalate ester di-(2-ethylhexyl) phthalate (DEHP) has been conducted in mature male albino ferrets. DEHP treatment caused a loss of body weight when administered as a 1% (w/w) diet for 14 months. Additionally, marked liver enlargement with associated morphological and biochemical changes was observed. These changes consisted of liver cell enlargement, lysosomal changes, dilatation of the endoplasmic reticulum and the depression of a number of marker enzyme activities. The only other tissue observed to be affected by DEHP treatment was the testes where histological evidence of tissue damage was observed in some animals.Studies on the metabolism of [¹⁴C]DEHP in the ferret indicated that the diester was metabolised to derivatives of mono-(2-ethylhexyl) phthalate which were excreted in the urine both unconjugated and as glucuronides.The results obtained have been compared with previous studies in the rat and it is concluded that DEHP is hepatotoxic in both species.     

Effect of di-2-ethylhexyl phthalate (DEHP) on glycogen metabolism in rat liver

Effect of di-2-ethylhexyl phthalate (DEHP) on glycogen contents and certain enzymes of carbohydrate metabolism of rat liver was investigated. A significant decrease in glycogen content of unfasted and an increase in fasted animals was observed. Blood glucose tolerance was reduced and the rate of both glycogenesis and glycogenolysis, as judged by measuring glycogen contents after feeding labelled and unlabelled glucose, was also decreased. Activities of glucose-6-phosphate dehydrogenase, phosphorylase and glucose-6-phosphatase were significantly decreased while activities of fructose-1-6-diphosphate and aldolase remained unaltered. The present results suggest that DEHP affects both glycogenesis and glycogenolysis in rat liver.     

Disposition of orally administered di-(2-ethylhexyl) phthalate and mono-(2-ethylhexyl) phthalate in the rat

The dispositon of di-(2-ethylhexyl) phthalate (DEHP) and mono-(2-ethylhexyl) phthalate (MEHP) was studied in the rat. Three hours after a single oral dose of DEHP (2.8 g/kg), plasma concentrations of 8.8±1.7 g/ml DEHP and 63.2±8.7 g/ml MEHP were reached. MEHP levels declined with a half-life of 5.2±0.5 h. The ratio of the area under the plasma concentration-time curve of MEHP to that of DEHP was 16.1±6.1. When ¹⁴CDEHP was administered, 19.3±3.3% of the radioactivity was excreted in the urine within 72 h, the rest being excreted in the faeces. The urinary excretion rate of total radioactivity declined with a half-life of 7.9±0.5 h. Single administration of MEHP (0.4 g/kg) resulted in plasma concentrations of 84.1±14.9 g/ml 3 h after dosing; the half-life of MEHP was 5.5±1.1 h. Multiple dosing with DEHP (2.8 g/kg/day) for 7 consecutive days produced no accumulation of DEHP or MEHP in plasma.     

Estrogenic activities of di-2-ethylhexyl phthalate

Phthalate esters are widespread in the environment. They have been described as being one of the most abundant man-made environmental contaminants that may be adverse to human health. Particularly, di-2-ethylhexyl phthalate (DEHP) has been shown to cause reproductive and developmental toxicity and is suspected to be an endocrine disruptor. The primary objective of this study is to determine the estrogenic activity of DEHP. Estrogenic activities of DEHP were studied by in vitro assays of human breast cancer MCF-7 cell proliferation. Estrogen-dependent MCF-7 cells were grown in RPMI1640 medium containing 10% fetal bovine serum. Five days before the addition of the test compounds, the cells were washed by phosphate balanced solution (PBS), and the medium was substituted with a phenol red-free RPMI1640 medium containing 5% dextral charcoalstripped Fetal Bovine Serum (FBS). Fresh medium was added to the respective test compounds and the control cell received only the vehicle (ethanol). The proliferation of MCF-7 cell was analyzed by the MTT assay, growth curves, mitotic index and colony forming efficiency. Compared with the ethanol control cells, the proliferation of tested cells treated with DEHP, like estradiol, was significantly enhanced and the activity of the cell proliferation reached the maximum at 1 × 10⁻³ mol/L DEHP. The relative proliferative potency of DEHP was 0.000 001 with a relative proliferative effect of 97.32%. During the log phase, the mitotic index of the tested cells treated with DEHP and estradiol was significantly increased. The cell cloning efficiency was enhanced, which was treated by 10⁻³ mol/L DEHP only for 48 hours. The results show a time-dependent and dose-dependent model. Di-2-ethylhexyl phthalate enhanced the proliferation of human breast cancer MCF-7 cells in vitro and might demonstrate an estrogenic activity.     

Assessment of the teratogenicity of di(2-ethylhexyl)phthalate and mono(2-ethylhexyl)phthalate in mice

Di(2-ethylhexyl)phthalate (DEHP) and mono(2-ethylhexyl)phthalate (MEHP) were administered PO or IP to pregnant ICR mice at varying doses on days 7, 8, and 9 of gestation. In groups given DEHP orally, resorptions and malformed fetuses increased significantly at 1,000 mg/kg. Fetal weights were also significantly suppressed. Anterior neural tube defects (anencephaly and exencephaly) were the malformations most commonly produced. No teratogenic effects were revealed by IP doses of DEHP and PO or IP doses of MEHP, although high doses were abortifacient and lethal to pregnant females. Thus DEHP is highly embryotoxic and teratogenic in mice when given PO but not IP. The difference in metabolism, disposition, or excretion by the route of administration may be responsible for the difference in DEHP teratogenicity. Although MEHP is a principal metabolite of DEHP and is several times more toxic than DEHP to adult mice, it seems that MEHP and its metabolites are not teratogenic in ICR mice.     

Effects of di-(2-ethylhexyl) phthalate on the hypothalamus-pituitary-ovarian axis in adult female rats

Di-(2-ethylhexyl) phthalate (DEHP), an environmental endocrine disruptor, is widely present in the environment and some products with phthalate plasticizer. It has become a serious problem in recent years. The effect of DEHP on female reproductive system is still not well-studied. This study was to investigate the effects of DEHP on hypothalamus-pituitary-ovarian axis in adult female rats. Compared with control rats, the DEHP-treated rats showed: (1) lower body weight; (2) lower organ coefficient of ovary; (3) higher GnRH level in the hypothalamus; (4) higher mRNA and protein levels of GnRHR in the pituitary; and (5) lower serum sex hormone levels. Our data reveal that DEHP exposure may lead to the disruption of estrogen biosynthesis pathways in female rats and imbalance of hypothalamus-pituitary-ovarian axis. DEHP may impose negative influence on the development and function of the reproductive system in female rats.     

Blood burden of di(2-ethylhexyl) phthalate and its primary metabolite mono(2-ethylhexyl) phthalate in pregnant and nonpregnant rats and marmosets

A comparison of the dose-dependent blood burden of di(2-ethylhexyl) phthalate (DEHP) and mono(2-ethylhexyl) phthalate (MEHP) in pregnant and nonpregnant rats and marmosets is presented. Sprague-Dawley rats and marmosets were treated orally with 30 or 500 mg DEHP/kg per day, nonpregnant animals on 7 (rats) and 29 (marmosets) consecutive days, pregnant animals on gestation days 14-19 (rats) and 96-124 (marmosets). In addition, rats received a single dose of 1000 mg DEHP/kg. Blood was collected up to 48 h after dosing. Concentrations of DEHP and MEHP in blood were determined by GC/MS. In rats, normalized areas under the concentration-time curves (AUCs) of DEHP were two orders of magnitude smaller than the normalized AUCs of the first metabolite MEHP. Metabolism of MEHP was saturable. Repeated DEHP treatment and pregnancy had only little influence on the normalized AUC of MEHP. In marmosets, most of MEHP concentration-time courses oscillated. Normalized AUCs of DEHP were at least one order of magnitude smaller than those of MEHP. In pregnant marmosets, normalized AUCs of MEHP were similar to those in nonpregnant animals with the exception that at 500 mg DEHP/kg per day, the normalized AUCs determined on gestation days 103, 117, and 124 were distinctly smaller. The maximum concentrations of MEHP in blood of marmosets were up to 7.5 times and the normalized AUCs up to 16 times lower than in rats receiving the same daily oral DEHP dose per kilogram of body weight. From this toxicokinetic comparison, DEHP can be expected to be several times less effective in the offspring of marmosets than in that of rats if the blood burden by MEHP in dams can be regarded as a dose surrogate for the MEHP burden in their fetuses.