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Prenatal exposure to propylparaben at human-relevant doses accelerates ovarian aging in adult mice Полный текст
2021
Li, Milu | Zhou, Su | Wu, Yaling | Li, Yan | Yan, Wei | Guo, Qingchun | Xi, Yueyue | Chen, Yingying | Li, Yuanyuan | Wu, Meng | Zhang, Jinjin | Wei, Jia | Wang, Shixuan
Embryonic exposure to environmental chemicals may result in specific chronic diseases in adulthood. Parabens, a type of environmental endocrine disruptors widely used in pharmaceuticals and cosmetics, have been shown to cause a decline in women's reproductive function. However, whether exposure to parabens during pregnancy also negatively affect the ovarian function of the female offspring in adulthood remains unclear. This study aims to investigate the effects of prenatal propylparaben (PrP) exposure on the ovarian function of adult mice aged 46 weeks, which is equivalent to the age of 40 years in women. Pregnant ICR mice were intraperitoneally injected with human-relevant doses of PrP (i.e., 0, 7.5, 90, and 450 mg/kg/day) during the fetal sex determination period—from embryonic day E7.5 to E13.5. Our results revealed that ovarian aging was accelerated in PrP-exposed mice at 46 weeks, with altered regularity of the estrous cycle, decreased serum estrogen (E2) and progesterone (P4) levels, reduced size of the primordial follicle pool, and increased number of atretic follicles. It was found that prenatal exposure to human-relevant doses of PrP exacerbated ovarian oxidative stress, inflammation, and fibrosis, which promoted follicular atresia by activating the mitochondrial apoptosis pathway. To compensate, the depletion of primordial follicles was also accelerated by activating the PI3K/AKT/mTOR signaling pathway in PrP-exposed mice. Moreover, PrP induced hypermethylation of CpG sites in the promoter region of Cyp11a1 (a 17.16–64.28% increase) partly led to the disrupted steroidogenesis, and the altered methylation levels of imprinted genes H19 and Peg3 may also contribute to the phenotypes observed. These remarkable findings highlight the embryonic origin of ovarian aging and suggest that a reduced use of PrP during pregnancy should be advocated.
Показать больше [+] Меньше [-]Biochemical profile and gene expression of Clarias gariepinus as a signature of heavy metal stress Полный текст
2020
Swaleh, Sadiya Binte | Banday, Umarah Zahoor | Asadi, Moneeb-Al | Usmani, Nazura
Heavy metals have been found in increasing concentrations in the aquatic environment. Fishes exposed to such metals have altered gene expression, serum profiles, tissue histology and bioindices that serve as overall health biomarkers. The heavy metals (Ni, Cd, and Cr) accumulated in water and fish tissues, were beyond the permissible limits defined by the Central Pollution Control Board/World Health Organization. Metallothionein (MT) and glutathione peroxidase (GPX) genes expression patterns highlighted the metal-specific exposure of fish. An increased fold change of genes against beta-actin serves as a potential feature for toxicity. Metal toxicity is also reflected by an increased level of digestive enzymes (amylase and lipase) in the serum and alterations in values of reproductive hormones (11-Ketotestosterone and progesterone). Total serum bilirubin attribute to the liver and biliary tract disease in fishes. Histopathological studies show cellular degeneration, breakage, vacuolization signifying the chronic stress.
Показать больше [+] Меньше [-]Impact of inorganic ions and pH variations on toxicity and endocrine potential of selected environmentally relevant pharmaceuticals Полный текст
2018
Wieczerzak, Monika | Kudłak, Błażej | Yotova, Galina | Tsakovski, Stefan | Simeonov, Vasil | Namieśnik, Jacek
Assessment of the impact of pharmaceutical residues on living organisms is a very complex subject. Apart from taking into account the toxicity of individual compounds, environmental factors should also be taken into account. In this paper, attempts were made to assess the impact of coexisting inorganic ions and changes in pH on the toxicity of ten selected pharmaceuticals. Two bioassays were used to measure the estrogenic and androgenic effects (XenoScreen YES/YAS – Saccharomyces cerevisiae) and acute toxicity (Microtox® – Vibrio fischeri).The Microtox® test gave the most definitive outputs concerning the determination of interaction type between drugs and chemical species. Synergism was proven for almost all drugs and chemical species, and only two cases of antagonism were found. Significant drug/pH interactions were rare.Regarding the XenoScreen YES/YAS bioassay, when estrogenic and androgenic agonistic effects (YES+ and YAS+, respectively) were studied, many cases of well-expressed synergism for all inorganic ions with limited number of drugs (diazepam, fluoxetine, estrone, chloramphenicol for the YES+ test and diazepam, progesterone, androstenedione, and estrone for the YAS+ test) were found. Antagonism was also proven for the YES+ test, especially for diclofenac and androstenedione interacting with cations. On the other hand, the YES- and YAS- tests (estrogenic and androgenic, respectively, antagonistic effects) did not indicate cases of synergetic interaction except for the couples Br−/diazepam and NH4+/ketoprofen. Antagonistic drug/ion interactions were detected only with diclofenac and fluoxetine. It is interesting that well-expressed (antagonism or synergism) drug/pH interactions were rare.Both tests were found utilizable in performing studies on impact of ions/pH fluctuations on drugs mixtures' toxicity confirming in most cases synergic impact of parameters studied on toxicity. The approach proposed in the paper seems to be proven as a reliable tool in assessing impact of abiotic factors on toxicity and endocrine potential of complex mixtures of pharmaceuticals' mixtures.
Показать больше [+] Меньше [-]Regulation of zebrafish (Danio rerio) locomotor behavior and circadian rhythm network by environmental steroid hormones Полный текст
2018
Zhao, Yanbin | Zhang, Kun | Fent, Karl
Environmental exposure of fish to steroid hormones through wastewater and agricultural runoff may pose a health risk. Thus far, ecotoxicological studies have largely been focused on the disruption of the sex hormone system, but additional effects have been poorly investigated. Here we report on the effects of a series of different natural and synthetic steroid hormones on the locomotor behavior and the transcriptional levels of core clock genes in zebrafish eleuthero-embryos (Danio rerio). Of the 20 steroids analyzed, progestins and corticosteroids, including progesterone and cortisol, significantly decreased the locomotor activities of eleuthero-embryos at concentrations as low as 16 ng/L, while estrogens such as 17β-estradiol led to an increase. Consistently, progestins and corticosteroids displayed similar transcriptional effects on core clock genes, which were remarkably different from those of estrogens. Of these genes, per1a and nr1d2a displayed the most pronounced alterations. They were induced upon exposure to various progestins and corticosteroids and could be recovered using the progesterone receptor/glucocorticoid receptor antagonist mifepristone; this, however, was not the case for estrogens and the estrogen receptor antagonist 4-hydroxy-tamoxifen. Our results suggest that steroid hormones can modulate the circadian molecular network in zebrafish and provide novel insights into their mode of actions and potential environmental risks.
Показать больше [+] Меньше [-]Steroid bioaccumulation profiles in typical freshwater aquaculture environments of South China and their human health risks via fish consumption Полный текст
2017
Liu, Shan | Xu, Xiang-Rong | Qi, Zhan-Hui | Chen, Hui | Hao, Qin-Wei | Hu, Yong-Xia | Zhao, Jian-Liang | Ying, Guang-Guo
More attention was previously paid to adverse effects of steroids on aquatic organisms and their ecological risks to the aquatic environment. So far, little information has been reported on the bioaccumulative characteristics of different classes of steroids in cultured fish tissues. The present study for the first time provided a comprehensive analysis of the occurrence, bioaccumulation, and global consumers’ health risks via fish consumption of androgens, glucocorticoids and progestanges in typical freshwater cultured farms in South China. The numbers and total concentrations of steroids detected in the tissues of five common species of the cultured fish were in the order of plasma > bile > liver > muscle and plasma > bile, muscle > liver, respectively. The field bioaccumulation factors for the detected synthetic steroids ranged from 450 to 97,000 in bile, 450 to 65,000 in plasma, 2900 to 16,000 in liver, and 42 to 2600 in muscle of fish, respectively. This data suggests that steroids are bioaccumulative in fish tissues. Mostly important, 4-androstene-3,17-dione (AED) and cortisone (CRN) were found to be reliable chemical indicators to predict the levels of steroids in plasma and muscle of the inter-species cultured fish, respectively. Furthermore, the maximum hazard quotients (HQs) of testosterone and progesterone were 5.8 × 10−4 and 9.9 × 10−5, suggesting that human health risks were negligible via ingestion of the steroids-contaminated fish.
Показать больше [+] Меньше [-]Chronic low-level perfluorooctane sulfonate (PFOS) exposure promotes testicular steroidogenesis through enhanced histone acetylation Полный текст
2021
Alam, Md Nur | Han, Xuejingping | Nan, Bingru | Liu, Liangpo | Tian, Meiping | Shen, Heqing | Huang, Qingyu
Perfluorooctane sulfonate (PFOS), an artificial perfluorinated compound, has been associated with male reproductive disorders. Histone modifications are important epigenetic mediators; however, the impact of PFOS exposure on testicular steroidogenesis through histone modification regulations remains to be elucidated. In this study, we examined the roles of histone modifications in regulating steroid hormone production in male rats chronically exposed to low-level PFOS. The results indicate that PFOS exposure significantly up-regulated the expressions of StAR, CYP11A1 and 3β-HSD, while CYP17A1 and 17β-HSD were down-regulated, thus contributing to the elevated progesterone and testosterone levels. Furthermore, PFOS significantly increased the histones H3K9me2, H3K9ac and H3K18ac while reduced H3K9me3 in rat testis. It is known that histone modifications are closely involved in gene transcription. Therefore, to investigate the association between histone modifications and steroidogenic gene regulation, the levels of these histone marks were further measured in steroidogenic gene promoter regions by ChIP. It was found that H3K18ac was augmented in Cyp11a1 promoter, and H3K9ac was increased in Hsd3b after PFOS exposure, which is proposed to result in the activation of CYP11A1 and 3β-HSD, respectively. To sum up, chronic low-level PFOS exposure activated key steroidogenic gene expression through enhancing histone acetylation (H3K9ac and H3K18ac), ultimately stimulating steroid hormone biosynthesis in rat testis.
Показать больше [+] Меньше [-]Antibiotics control in aquaculture requires more than antibiotic-free feeds: A tilapia farming case Полный текст
2021
Zhou, Min | Yu, Shen | Hong, Bing | Li, Juan | Han, Han | Qie, Guang
Public concern over the health implications of antimicrobials employed in aquaculture has resulted in adoption of strict regulations for their use. This study employed a high-throughput protocol covering 86 compounds in six pharmaceutical groups to screen feed and sediments from 20 tilapia ponds randomly in 18 farms of an aquacultural unit in southern China, one of important tilapia fillet suppliers in the world. Seventeen samples of commercial feeds from manufacturer-sealed bags in the farms were tetracyclines-free but not antibiotic-free. All the sealed-bag feeds contained quinolones and two feeds had sulfonamides (up to 140 μg kg⁻¹). Meanwhile, seven leftover-feeds in opened bags contained added antimicrobials: tetracyclines (570–2790 μg kg⁻¹) in all and florfenicol (20–294 μg kg⁻¹) in four. All the feeds regardless sealed or not had large amounts (221–2642 μg kg⁻¹) of salicylic acid (possible antimicrobial substitute) and caffeine, and one sealed-bag feed even was quantified with medroxyprogesterone. Surface sediments (0–10 cm) from the ponds were detected with 36 compounds and sublayer sediments (10–20) with 8 compounds. Large amounts of salicylic acid were present in both surface and sublayer sediments accounting up to 10% of total pharmaceutical residues. Surface sediments were dominated by antibiotics (5.2–172 μg kg⁻¹), mainly sulfonamides and quinolones, contributing 68% of the total quantitative compound mass. Sublayer sediments were also enriched in quinolones (up to 260 μg kg⁻¹). Surprisingly, all sediments contained progesterone (up to 8.0 μg kg⁻¹) in coincidence to the feed with medroxyprogesterone, perhaps arising from endocrine abuses or cross-contamination. Although high levels of other pharmacologic residues (caffeine) in sediment posed greater than medium ecological risks, antibiotic residues contributed only 2–35% to the risk. These findings suggest that antibiotic-free feed may be insufficient to control antibiotic abuse in aquaculture and that additional regulatory actions may be necessary, such as veterinary prescription as human antibiotic uses.
Показать больше [+] Меньше [-]Exposure to Benzo[a]pyrene impairs the corpus luteum vascular network in rats during early pregnancy Полный текст
2020
Liu, Min | Deng, Ting | He, Junlin | Ding, Yubin | Liu, Xueqing | Xu, Hanting | Gao, Rufei | Mu, Xinyi | Geng, Yanqing | Liu, Taihang | Wang, Yingxiong | Chen, Xuemei
Benzo [a]pyrene (BaP) is a well-known endocrine disruptor. Exposure to BaP is known to impair embryo implantation. The corpus luteum (CL), the primary source of progesterone during early pregnancy, plays a pivotal role in embryo implantation and pregnancy maintenance. The inappropriate luteal function may result in implantation failure and spontaneous abortions. However, the effect of BaP on CL remains unknown. This study investigated the deleterious effects of BaP on the structure and function of CL during early pregnancy. Pregnant rats were dosed with BaP at 0.2 mg.kg-1. d from day 1 (D1) to day 9 (D9) of gestation. We found that BaP reduced the number of CLs, disturbed the secretion of steroid and impacted the luteal vascular networks. BaP significantly decreased the angiogenesis factor (VEGFR, Ang-1 and Tie2) and increased the anti-angiogenic factor THBS1. Inhibited THBS1 function by LSKL partially rescued the angiogenesis defect caused by BaP. In vitro, BaP metabolite BPDE also interfered the expression levels of angiogenesis-related factors in HUVECs and impaired the angiogenesis, whereas supplemented with rAng-1 can alleviate the anti-angiogenic effect of BPDE. Furthermore, Notch signaling molecules, including Notch1, Dll4, Jag1 and Hey2, which are essential for the establishment and maturation of vascular networks, were affected by BaP exposure. Collectively, BaP broke the molecular regulatory balance between luteal angiogenesis and vascular maturation, impaired the construction of luteal vascular networks, and further affected luteal formation and endocrine function during early pregnancy. Our findings might provide new insight into the relationship between BaP and luteal insufficiency in early pregnancy. These data also give a new line of evidence for curtailing BaP emissions and protecting the women of childbearing age from occupational exposure.
Показать больше [+] Меньше [-]Bisphenols (A, S, and F) affect the basic hormonal activity determined for pharmaceuticals – Study of Saccharomyces cerevisiae Полный текст
2019
Kudłak, Błażej | Wieczerzak, Monika | Namieśnik, Jacek
Pharmaceuticals and analogs of bisphenol A (BPA) are increasingly threatening environmental pollutants. In this study, mixtures of selected pharmaceuticals (diclofenac sodium salt, chloramphenicol, oxytetracycline hydrochloride, fluoxetine hydrochloride, estrone, ketoprofen, progesterone, gemfibrozil and androstenedione) were prepared with BPA and its two analogs (namely, bisphenols F and S) at such ratios to reflect environmentally detectable levels. Then, the mixture solutions were studied with a XenoScreen YES/YAS assay to determine the variations in the initial hormonal response of each pharmaceutical compound due to the presence of a bisphenol analog. The results obtained were modeled with the concentration addition (CA) and independent action (IA) approaches, the trueness of which was studied with model deviation ratios (MDR). The estrogenic agonistic activity of the drugs studied was most strongly affected by the presence of BPA in solution (twenty-one cases of synergy observed for CA models versus twelve cases of antagonism in the case of IA predictions). BPS shows a strong agonistic estrogenic impact on most of the drugs studied at medium and high concentration levels; androgenic agonistic activity was also impaired with elevated concentrations of BPS. Increasing the concentration of BPF in a reaction mixture also increased the number of YES + synergism incidences (for CA modeling). Estrone, progesterone and androstenedione were mostly affected by the highest BPF concentrations studied in the case of androgenic agonistic research performed.
Показать больше [+] Меньше [-]Occurrence and level of emerging organic contaminant in fish and mollusk from Klang River estuary, Malaysia and assessment on human health risk Полный текст
2019
Omar, T.F.T. | Ahmad Zaharin Aris, | Fatimah Md. Yusoff, | Mustafa, Shuhaimi
The occurrence, level, and distribution of multiclass emerging organic contaminants (EOCs) in fish and mollusks from the Klang River estuary were examined. The targeted EOCs for this assessment were phenolic endocrine disrupting compounds (bisphenol A, 4-OP, and 4-NP), organophosphorous pesticides (quinalphos, chlorpyrifos, and diazinon), estrogenic hormones (E2, E1, and EE2), and pharmaceutically active chemicals (primidone, sulfamethoxazole, dexamethasone, diclofenac, amoxicillin, progesterone, and testosterone). Results from this study showed that the prevalent contamination of the Klang River estuary by EOCs with diclofenac, bisphenol A, progesterone, and amoxicillin were predominantly detected in fish and mollusks. Among the EOCs, diclofenac and progesterone had the highest concentrations in fish and mollusk samples, respectively. The concentrations of diclofenac and progesterone in fish and mollusk samples range from 1.42 ng/g to 10.76 ng/g and from 0.73 ng/g to 9.57 ng/g, respectively. Bisphenol A should also be highlighted because of its significant presence in both fish and mollusks. The concentration of bisphenol A in both matrices range from 0.92 ng/g to 5.79 ng/g. The calculated hazard quotient (HQ) for diclofenac, bisphenol A, and progesterone without consideration to their degradation byproduct were less than one, thus suggesting that the consumption of fish and mollusks from the Klang River estuary will unlikely pose any health risk to consumers on the basis of the current assessment. Nonetheless, this preliminary result is an important finding for pollution studies in Malaysian tropical coastal ecosystems, particularly for organic micropollutant EOCs, and can serve as a baseline database for future reference.
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