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Pubertal Bisphenol A exposure increases adult rat serum testosterone by resetting pituitary homeostasis 全文
2022
Chen, Dan | Zhao, Xingyi | Huang, Fu | Guan, Xiaoju | Tian, Jing | Ji, Minpeng | Wen, Xin | Shao, Jingjing | Xie, Jiajia | Wang, Jiexia | Chen, Haolin
Bisphenol A (BPA) is widely used by manufacturers and in consumer products. Its release in the environment may affect male reproductive function. In this study, we examined the effect of low dose (0.1 mg/kg BW), short term exposure during puberty (PD21-35) on adult rat male reproduction. The results indicated that such exposure reset growth hormone (GH) and follicular stimulating hormone (FSH) homeostasis and resulted in a significantly higher level of serum testosterone without affecting serum luteinizing hormone level. QPCR and Western blot results showed that BPA significantly up-regulated selective genes/proteins in the Leydig cell steroidogenic pathway, including steroidogenic acute regulatory protein, cytochrome P450 11A1, cytochrome P450 17A, and low-density lipoprotein receptor. RNA-Seq analysis of testicular RNAs showed that BPA significantly affected the gene profiles of multiple testicular interstitial populations without affecting germ cells. Also, GO- and KEGG-analysis suggested that IGF1-related PI3K/AKT signaling was activated, which was confirmed by the increased phosphorylation of IRS1, AKT1 and CREB. The results indicated that a low-dose, short-term BPA exposure during puberty affected the adult male rat pituitary (GH and FSH) and testis (testosterone) homeostasis.
显示更多 [+] 显示较少 [-]Mitigation effects of exogenous melatonin-selenium nanoparticles on arsenic-induced stress in Brassica napus 全文
2022
Farooq, Muhammad Ahsan | Islam, Faisal | Ayyaz, Ahsan | Chen, Weiqi | Noor, Yamna | Hu, Weizhen | Hannan, Fakhir | Zhou, Weijun
Melatonin (MT) and selenium (Se) application known to decrease heavy metal uptake and toxicity in plants. By mixing the Se in MT medium a new complex MT-Se nanoparticles (MT-Se NPs) was synthesized and we investigated the role of MT-Se NPs on B. napus growth and tolerance against As stress. The MT-Se particles significantly enhanced the plant growth and other associated physiological attributes under As stress. The As treatment at 80 μM was more phytotoxic, however MT-Se NPs application resulted in a substantial increase in leaf chlorophyll fluorescence, biomass accumulation, and decreased ROS relative to As stressed plants. The use of MT-Se NPs to As stressed plants reduced photosynthetic inhibition and oxidative stress and attenuated the increase in MDA and H₂O₂ contents. The application of MT-Se NPs also boosted the antioxidant enzymes activities such as SOD, POD and CAT as well as the APX, GR and GSH activates under As stress. The results also showed MT-Se NPs treatments alleviated the growth inhibition induced by As and reduced the accumulation of As in leaves and roots of B. napus seedlings. Moreover, treatment with MT-Se NPs improved the plant growth more successfully than treatment of MT and Se alone. This study explored the mechanism of melatonin and selenium efficiency in the composition can be jointly encouraged to exert synergistic effects and boost plant enzymatic activities.
显示更多 [+] 显示较少 [-]Physiochemical responses of earthworms (Eisenia fetida) under exposure to lanthanum and cerium alone or in combination in artificial and contaminated soils 全文
2022
Tang, Wantong | Wang, Guiyin | Zhang, Shirong | Li, Ting | Xu, Xiaoxun | Deng, Ouping | Luo, Ling | He, Yan | Zhou, Wei
Rare earth elements inevitably release into the soil due to their widespread application. However, it is unclear how they affect the soil animals. The study surveyed the growth and physiological responses of earthworm (Eisenia fetida) exposed into artificial soils spiked with La, Ce, and their mixture, and actual mine soil collected from an abandoned La–Ce mining area (Mianning, Sichuan). The results showed that the 1000–1200 mg/kg combined exposure in two soils induced significant histopathological and phenotypic changes of earthworms. Concentration significantly affected the superoxide dismutase (SOD), peroxidase (POD), malondialdehyde (MDA), and protein of E. fetida and the effects differentiated with the prolonging duration. These indicators were negatively affected under the La stress ≥800 mg/kg (SOD, POD, and protein), the 1200 mg/kg (SOD), Ce stress ≥1000 mg/kg (protein), and the combination ≥800 mg/kg (SOD, POD) and ≥1000 mg/kg (protein). Artificial combination had −15.04% (SOD), 8.87% (POD), 5.64% (MDA), and −8.34% (protein) difference compared with the contamination soil, respectively. Overall, E. fetida respond sensitively under the La and Ce stress, the antioxidant defense system and the lipid peroxidation were stimulated, and the artificial soil might overestimate eco-toxicological effect.
显示更多 [+] 显示较少 [-]The influences of ambient fine particulate matter constituents on plasma hormones, circulating TMAO levels and blood pressure: A panel study in China 全文
2022
Wang, Jiajia | Wu, Shenshen | Cui, Jian | Ding, Zhen | Meng, Qingtao | Sun, Hao | Li, Bin | Teng, Jun | Dong, Yanping | Aschner, Michael | Wu, Ziyuan | Li, Xiaobo | Chen, Rui
Considerable investigations have been carried out to address the relationship between ambient fine particulate matter (PM₂.₅) and blood pressure (BP) in patients with hypertension. However, few studies have explored the influence of PM₂.₅ and its constituents on Trimethylamine N-oxide (TMAO), an established risk factor for hypertension and cardiovascular disease (CVD), particularly in severely air-polluted areas. To explore the potential impact of PM₂.₅ constituents on BP, plasma hormones, and TMAO, a panel study was conducted to investigate changes in BP, plasma hormones, and TMAO in response to ambient air pollution exposure in stage 1 hypertensive young adults. Linear mixed effect models were used to estimate the cumulative effects of fine particulate matters (PM₂.₅) and its constituents on BP, plasma hormones and TMAO. We found that one interquartile range (IQR) (35 μg/m³) increase in 0–1 day moving-average PM₂.₅ concentrations was statistically significantly associated with elevated systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) with estimated values of 0.13 (95% confidence interval (CI): 0.03 to 0.23) mmHg, 0.18 (95% CI: 0.08 to 0.28) mmHg, and 0.17 (95% CI: 0.09 to 0.26) mmHg, respectively. Hormone disturbance in the renin-angiotensin-aldosterone system was also associated with PM₂.₅ exposure. Elevated TMAO levels with an IQR increase for 0–4, 0–5, 0–6 moving-average concentrations of PM₂.₅ were found, and the increased values ranged from 26.28 (95% CI: 2.92 to 49.64) to 60.78 (31.95–89.61) ng/ml. More importantly, the PM₂.₅-bound metal constituents, such as manganese (Mn), titanium (Ti), and selenium (Se) showed robust associations with elevated BP and plasma TMAO levels. This study demonstrates associations between PM₂.₅ metal constituents and increased BP, changes in plasma hormones and TMAO, in stage 1 hypertensive young adults. Source control, aiming to reduce the emission of PM₂.₅-bound metals should be implemented to reduce the risk of hypertension and CVD.
显示更多 [+] 显示较少 [-]Evaluating the applicability of the ratio of PM2.5 and carbon monoxide as source signatures 全文
2022
Xiu, Meng | Jayaratne, Rohan | Thái Phong, | Christensen, Bryce | Zing, Isak | Liu, Xiaoting | Morawska, L. (Lidia)
Air pollution is among the top risk faced by people around the world, and therefore combating it is among the top priorities. It begins with identifying the sources that contribute the most to local air pollution to prioritize their control. There are advanced methods for source identification and apportionment, but such methods are not available in many low-income countries and not everywhere in all high-income countries. We propose a simplified method by using source the signatures to help obtain information about the local source contribution if no other methods are available. Using low-cost monitors, particle mass (PM₂.₅) and carbon monoxide (CO) concentrations were measured and the ratio of CO/PM₂.₅ was determined. We investigated outdoor and indoor sources, including vehicular exhaust, combustion of biomass, incense and mosquito coil burning, and cigarette smoking. The results show that the ratios differed significantly between certain pollutant sources. Compressed natural gas (CNG) engines have a high ratio (mean value of 972 ± 419), which is attributed to relatively low PM₂.₅ emissions, while ship emissions and cigarette smoke recorded a relatively low ratio. Most traffic emissions recorded higher ratios than those of bushfire emissions, and ratios of most outdoor pollutant sources were much higher than those of indoor pollutant sources. There is a clear trend for ratios to decrease from high to low for CNG, petrol, diesel for buses, and fuel for ships. Our results suggest that the ratio of CO/PM₂.₅ can be used as an effective method to identify pollution sources.
显示更多 [+] 显示较少 [-]Size-dependent in vitro inhalation bioaccessibility of PAHs and O/N PAHs - Implications to inhalation risk assessment 全文
2022
Besis, Athanasios | Gallou, Domniki | Avgenikou, Anna | Serafeim, Eleni | Samara, Constantini
Size segregated samples (<0.49, 0.49–0.95, 0.95–1.5, 1.5–3.0, 3.0–7.2 and > 7.2 μm) of atmospheric particulate matter (APM) were collected at a traffic site in the urban agglomeration of Thessaloniki, northern Greece, during the cold and the warm period of 2020. The solvent-extractable organic matter was analyzed for selected organic contaminants including polycyclic aromatic hydrocarbons (PAHs), and their nitro- and oxy-derivarives (NPAHs and OPAHs, respectively). Mean concentrations of ∑₁₆PAHs, ∑₆NPAHs and ∑₁₀OPAHs associated to total suspended particles (TSP) were 18 ng m⁻³, 0.2 ng m⁻³ and 0.9 ng m⁻³, respectively, in the cold period exhibiting significant decrease (6.4, 0.2 and 0.09 ng m⁻³, respectively) in the warm period. The major amount of all compounds was found to be associated with the alveolar particle size fraction <0.49 μm. The inhalation bioaccessibility of PAHs and O/N PAHs was measured in vitro using two simulated lung fluids (SLFs), the Gamble's solution (GS) and the artificial lysosomal fluid (ALF). With both SLFs, the derived bioaccessible fractions (BAFs) followed the order PAHs > OPAHs > NPAHs. Although no clear dependence of bioaccessibility on particle size was obtained, increased bioaccessibility of PAHs and PAH derivatives in coarse particles (>7.2 μm) was evident. Bioaccessibility was found to be strongly related to the logKOW and the water solubility of individual compounds hindering limited mobilization of the most hydrophobic and less water-soluble compounds from APM to SLFs. The lifetime cancer risk due to inhalation exposure to bioaccessible PAHs, NPAHs and OPAHs was estimated and compared to those calculated from the particulate concentrations of organic contaminants.
显示更多 [+] 显示较少 [-]Perfluorooctane sulfonate induces suppression of testosterone biosynthesis via Sertoli cell-derived exosomal/miR-9-3p downregulating StAR expression in Leydig cells 全文
2022
Huang, Jiyan | Ren, Hang | Tan, Annie | Li, Ting | Wang, Hongxia | Jiang, Lianlian | Zheng, Shaokai | Qi, Han | Ji, Binyan | Wang, Xipei | Qu, Jianhua | Zhao, Jianya | Qiu, Lianglin
Perfluorooctane sulfonate (PFOS) is associated with male reproductive disorder, but the related mechanisms are still unclear. In this study, we used in vivo and in vitro models to explore the role of Sertoli cell-derived exosomes (SC-Exo)/miR-9-3p/StAR signaling pathway on PFOS-induced suppression of testosterone biosynthesis. Forty male ICR mice were orally administrated PFOS (0.5–10 mg/kg/bw) for 4 weeks. Bodyweight, organ index, sperm count, reproductive hormones were evaluated. Primary Sertoli cells and Leydig cells were used to delineate the molecular mechanisms that mediate the effects of PFOS on testosterone biosynthesis. Our results demonstrated that PFOS dose-dependently induced a decrease in sperm count, low levels of testosterone, and damage in testicular interstitium morphology. In vitro models, PFOS significantly increased miR-9-3p levels in Sertoli cells and SC-Exo, accompanied by a decrease in testosterone secretion and StAR expression in Leydig cells when Leydig cells were exposed to SC-Exo. Meanwhile, inhibition of SC-Exo or miR-9-3p by their inhibitors significantly rescued PFOS-induced decreases in testosterone secretion and the mRNA and protein expression of the StAR gene in Leydig cells. In summary, the present study highlights the role of the SC-Exo/miR-9-3p/StAR signaling pathway in PFOS-induced suppression of testosterone biosynthesis, advancing our understanding of molecular mechanisms for PFOS-induced male reproductive disorders.
显示更多 [+] 显示较少 [-]Metabolic response of earthworms (Pheretima guillemi) to silver nanoparticles in sludge-amended soil 全文
2022
Li, Min | Ruan, Ling-Yu | Dang, Fei | Liu, Hai-Long | Zhou, Dong-Mei | Yin, Bin | Wang, Jun-Song
Silver nanoparticles (AgNPs) can enter soils via the application of sludge and pose risks to soil invertebrates. However, current knowledge regarding the toxicity of AgNPs at environmentally relevant concentration is insufficient, especially at the molecular level. Therefore, we examined the effects of low-level AgNPs (7.2 mg kg⁻¹, dry weight) on the bioaccumulation, pathology and metabolism of earthworms (Pheretima guillemi). After exposure for 28 d, earthworms were dissected into digestive system and the rest of the body to explore the response of different body parts to AgNPs. Ag concentration in the digestive system of exposed group (2.5 mg kg⁻¹, dry weight) was significantly higher than that of the control group (0.5 mg kg⁻¹, dry weight). AgNPs exposure had no significant effects on the survival and growth, but induced intestinal damage and metabolic interference to earthworms relative to the control. Metabolomics analysis showed that AgNPs exposure disturbed the glycerophospholipid metabolism, glutathione metabolism and energy metabolism in the digestive system and the energy metabolism in the rest of the body. AgNPs exposure also induced lipid peroxidation in the digestive system. The different metabolic responses between two body parts highlighted the importance of the uptake routes of Ag. These results provide a biochemical insight for the risk assessment of low-level AgNPs in terrestrial environment.
显示更多 [+] 显示较少 [-]Overestimation of anthropogenic contribution of heavy metals in precipitation than those of aerosol samples due to different treatment methods 全文
2022
Xu, Yinbo | Li, Qing | Xie, Shiyou | Zhang, Chao | Yan, Fangping | Liu, Yixi | Kang, Shichang | Gao, Shaopeng | Li, Yizhong
Due to increased anthropogenic activities in recent decades, many heavy metal elements have been emitted into the atmosphere and transported to remote regions. The Enrichment factors (EFs) is a normally used method for evaluating the source of heavy metal elements. However, because of some flaws of this method (e.g., higher solubility of heavy metals elements than reference elements in dilute acid), the anthropogenic contributions of some heavy metal elements in the precipitation sample were overestimated. To address this issue, EFs of heavy metal elements of aerosol, precipitation and snowpit samples in a typical remote area of the Tibetan Plateau (TP) were compared. The results showed that the EF values of many heavy metal elements in precipitation and snowpit samples were close to that of aerosol samples treated with dilute acid but usually much higher than those of totally dissolved aerosol samples. Moreover, EF values of most heavy metal elements in the ice core at the margin of the TP were higher than those at central TP, indicating that signal of long-range transport anthropogenic emitted heavy metal elements is weak and may be covered by natural mineral dust sources at glacier region. Therefore, the threshold EF values for determining anthropogenic sources of heavy metal elements in precipitation and ice core samples should be higher than those of aerosols. This study provides new knowledge on investigating anthropogenic sources of heavy metals in precipitation samples at both the TP and other regions of the world.
显示更多 [+] 显示较少 [-]Microplastics impact shell and pearl biomineralization of the pearl oyster Pinctada fucata 全文
2022
Han, Zaiming | Jiang, Taifeng | Xie, Liping | Zhang, Rongqing
Microplastics are extremely widespread aquatic pollutants that severely detriment marine life. In this study, the influence of microplastics on biomineralization was investigated. For the first time, multiple forms and types of microplastics were detected and isolated from the shells and pearls of Pinctada fucata. According to the present study, the abundance of microplastics in shells and pearls was estimated at 1.95 ± 1.43 items/g and 0.53 ± 0.37 items/g respectively. Interestingly, microplastics were less abundant in high-quality round pearls. Microplastics may hinder the growth of calcite and aragonite crystals, which are crucial components required for shell formation. During the process of biomineralization microplastics became embedded in shells, suggesting the existence of a novel pathway by which microplastics accumulate in bivalves. After a 96-h exposure to microplastics, the expression level of typical biomineralization-related genes increased, including amorphous calcium carbonate binding protein (ACCBP) gene which experienced a significant increase. ACCBP promotes the formation of amorphous calcium carbonate (ACC), which is the pivotal precursor of shell formation-related biominerals. ACCBP is highly expressed during the developmental stage of juvenile oysters and the shell-damage repair process. The increased expression of ACCBP suggests biomineralization is enhanced as a result of microplastics exposure. These results provide important evidence that microplastics exposure may impact the appearance of biominerals and the expression of biomineralization-related genes, posing a new potential threat to aquatic organisms.
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