scholarly journals TDCPP exposure affects the concentrations of thyroid hormones in zebrafish

2017 ◽  
Author(s):  
Jingxin Song

AbstractPrevious studies show that TDCPP may interrupt the thyroid endocrine system, however, the potential mechanisms involved in these processes were largely unknown. In this study, zebrafish embryos/larvae were exposed to TDCPP until 120 hpf, by which time most of the organs of the larvae have completed development. In this study, the effects of TDCPP on HPT axis were examined and the thyroid hormone levels were measured after TDCPP treatment. Zebrafish (Danio rerio) embryos were treated with a series concentration of TDCPP (10, 20, 40, 80, 160 and 320 μg/L) from 1 day post-fertilization (dpf) to 5 dpf. Exposure concentrations of TDCPP were determined based on the survival rates in each group. Total mRNA were isolated, first-strand cDNA were synthesis and qPCR were performed to detect the mRNA expression levels in hypothalamic-pituitary-thyroid (HPT) axis. The mRNA expression levels of genes involved in thyroid hormone homeostasis were increased in the TDCPP-treated larvae. The mRNA levels of genes involved in thyroid hormone synthesis were also increased in the embryos treated with TDCPP. Furthermore, exposure to TDCPP led to a dose-dependent effect on zebrafish development, including diminished hatching and survival rates, increased malformation. TDCPP treatment significantly reduced the T4 concentration in the 5 dpf zebrafish larvae, but increased the concentration of T3, suggesting the function of thyroid endocrine were interrupted in the TDCPP-exposed zebrafish. Taken together, these data indicated that TDCPP affected the thyroid hormone levels in the zebrafish larvae and could increased the mRNA expression levels of genes related to HPT axis, which further impaired the endocrine homeostasis and thyroid system.

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A849-A849
Author(s):  
Ricardo H Costa e Sousa ◽  
Rodrigo Rorato ◽  
Anthony Neil Hollenberg ◽  
Kristen R Vella

Abstract Thyroid hormone (TH) is a major regulator of development and metabolism. An important mechanism controlling TH production is the negative feedback at the hypothalamic and pituitary level and it has been suggested that thyroid hormone receptor β (TRβ) is the main mediator of TH actions in the hypothalamic paraventricular nucleus (PVN). Nevertheless, the direct actions of TH and TRβ in the negative regulation of TRH have yet to be demonstrated in vivo. Here we used two approaches to investigate the TRH neuron. First, we used a chemogenetic tool to directly investigate the role of TRH neurons on the regulation of thyroid hormone levels. Mice expressing Cre-recombinase in TRH neurons received bilateral injections of the activating designer receptors exclusively activated by designer drugs (DREADD) directly into the PVN. Activation of TRH neurons produced a rapid and sustained increase in circulating TSH levels in both males and females. TSH levels increased approximately 10-fold from baseline within 15 minutes of injection of CNO, returning to baseline within 2.5 hours. TH levels were increased approximately 2-fold in males and females. Therefore, using a chemogenetic approach, we were able to directly evaluated the role of PVN TRH neurons on the control of thyroid activity, for the first time. Next, we generated mice deficient in TRβ specifically in neurons expressing melanocortin 4 receptor (MC4R), which overlaps with TRH expression in the PVN. Knockout mice (KO) developed normally and showed no change in TH and TSH levels. TRH mRNA levels in the PVN of KO mice were similar to control mice. To investigate if the deletion of TRβ in the PVN changes the sensitivity of the HPT axis to T3, mice were rendered hypothyroid and given increasing doses of T3 for 2 weeks. Results show no difference in TRH mRNA or serum TSH between controls and KO. Surprisingly, despite the presence of detectable genomic recombination on the TRβ gene in the PVN, there was no difference in TRβ mRNA expression between control and KO mice, suggesting that either MC4R-positive neurons do not express TRβ or they represent a very small population of TRβ-positive cells in the PVN. Present data show that TRH neuron activation rapidly stimulates TSH release and increases TH levels, demonstrating a major role of these neurons in the regulation of the hypothalamic-pituitary-thyroid (HPT) axis. Nevertheless, deletion of TRβ from MC4R neurons had no major effect on either TRH or TH levels in in mice. Additionally, TRβ in MC4R-positive TRH neurons in the PVN is not necessary for TH-induced suppression of TRH mRNA. Although further studies are necessary, these data suggest that there are distinct populations of hypophysiotropic TRH neurons in the PVN, some of which are not regulated by thyroid hormone and TRβ.


2017 ◽  
Author(s):  
Lianqiang Cheng ◽  
Xiaowen Wang ◽  
Shijun Li ◽  
Yongjun Liu ◽  
Zhengxin Guo

AbstractThe estrogen receptor (ER) genes, which encode a group of important ligand-activated transcriptional factors, can modulate estrogen-target gene activities. Zebrafish (Danio rerio) have three ER receptor genes, esr1, esr2a, and esr2b. In this study, we examined the mRNA expression levels of these ER receptors after treatment with mestranol (EE3ME). Zebrafish larvae were exposed to 0.01, 0.1, 1, and 10 mg/L from 6 hours post-fertilization (hpf) and the mRNA expression levels of the ER genes were determined at 24, 48, 72 and 96 hpf. Treatment with mestranol led to a significant stimulation of esr1 mRNA expression at lower concentration and reached maximum at 72 hpf, however, the esr1 mRNA levels were reduced at higher mestranol concentration during exposure. The gene expression of esr2b was markedly decreased and the esr2a remained unaffected at all concentration in the duration. Altogether, these results suggested mestranol might cause the disruption of endocrine activities in fish by mediating ER genes expression.


2019 ◽  
Vol 20 (13) ◽  
pp. 3257 ◽  
Author(s):  
Sophie Gravel ◽  
Benoit Panzini ◽  
Francois Belanger ◽  
Jacques Turgeon ◽  
Veronique Michaud

To characterize effects of type 2 diabetes (T2D) on mRNA expression levels for 10 Cytochromes P450 (CYP450s), two carboxylesterases, and three drug transporters (ABCB1, ABCG2, SLCO2B1) in human duodenal biopsies. To compare drug metabolizing enzyme activities of four CYP450 isoenzymes in duodenal biopsies from patients with or without T2D. mRNA levels were quantified (RT-qPCR) in human duodenal biopsies obtained from patients with (n = 20) or without (n = 16) T2D undergoing a scheduled gastro-intestinal endoscopy. CYP450 activities were determined following incubation of biopsy homogenates with probe substrates for CYP2B6 (bupropion), CYP2C9 (tolbutamide), CYP2J2 (ebastine), and CYP3A4/5 (midazolam). Covariables related to inflammation, T2D, demographic, and genetics were investigated. T2D had no major effects on mRNA levels of all enzymes and transporters assessed. Formation rates of metabolites (pmoles mg protein−1 min−1) determined by LC-MS/MS for CYP2C9 (0.48 ± 0.26 vs. 0.41 ± 0.12), CYP2J2 (2.16 ± 1.70 vs. 1.69 ± 0.93), and CYP3A (5.25 ± 3.72 vs. 5.02 ± 4.76) were not different between biopsies obtained from individuals with or without T2D (p > 0.05). No CYP2B6 specific activity was measured. TNF-α levels were higher in T2D patients but did not correlate with any changes in mRNA expression levels for drug metabolizing enzymes or transporters in the duodenum. T2D did not modulate expression or activity of tested drug metabolizing enzymes and transporters in the human duodenum. Previously reported changes in drug oral clearances in patients with T2D could be due to a tissue-specific disease modulation occurring in the liver and/or in other parts of the intestines.


2021 ◽  
Vol 28 (5) ◽  
pp. 4080-4092
Author(s):  
Takahiro Ichikawa ◽  
Masahiro Shibata ◽  
Takahiro Inaishi ◽  
Ikumi Soeda ◽  
Mitsuro Kanda ◽  
...  

Background: Accumulating evidence indicates tumor-promoting roles of synaptotagmin 13 (SYT13) in several cancers; however, no studies have investigated its expression in breast cancer (BC). This study aimed to clarify the significance of SYT13 in BC. Methods: SYT13 mRNA expression levels were evaluated in BC cell lines. Polymerase chain reaction (PCR) array analysis was conducted to determine the correlation between expression levels of SYT13 and other tumor-associated genes. Then, the association of SYT13 expression levels in the clinical BC specimens with patients’ clinicopathological factors was evaluated. These findings were subsequently validated using The Cancer Genome Atlas (TCGA) database. Results: Among 13 BC cell lines, estrogen receptor (ER)-positive cells showed higher SYT13 mRNA levels than ER-negative cells. PCR array analysis revealed positive correlations between SYT13 and several oncogenes predominantly expressed in ER-positive BC, such as estrogen receptor 1, AKT serine/threonine kinase 1, and cyclin-dependent kinases 4. In 165 patients, ER-positive specimens exhibited higher SYT13 mRNA expression levels than ER-negative specimens. The TCGA database analysis confirmed that patients with ER-positive BC expressed higher SYT13 levels than ER-negative patients. Conclusion: This study suggests that SYT13 is highly expressed in ER-positive BC cells and clinical specimens, and there is a positive association of SYT13 with the ER signaling pathways.


2011 ◽  
Vol 120 (2) ◽  
pp. 392-402 ◽  
Author(s):  
Viengtha Vongphachan ◽  
Cristina G. Cassone ◽  
Dongmei Wu ◽  
Suzanne Chiu ◽  
Doug Crump ◽  
...  

2020 ◽  
Vol 12 ◽  
pp. 175883592091756
Author(s):  
Jing-Hua Yang ◽  
Ming-Zhe Wu ◽  
Xu-Bo Wang ◽  
Shiyu Wang ◽  
Xue-Shan Qiu ◽  
...  

Background: There is an immediate need for research on the mechanism underlying telomerase activation and overexpression. Materials & Methods: A total of 174 patients with lung cancer ( n = 106) and benign lung disease ( n = 68) were recruited for the current study. The mRNA expression levels of E6, E7, LKB1, Sp1, and hTERC in brushing cells were detected by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), and hTERC amplification was also detected by fluorescence in situ hybridization (FISH). To investigate the potential mechanism, bidirectional genetic manipulation was performed in well-established lung cancer cell lines. Results: Our results indicated that the mRNA expression levels of E6, E7, Sp1, and hTERC and the amplification level of hTERC were significantly increased in the malignant group compared with those of the benign group ( p < 0.01). Conversely, the mRNA expression level of LKB1 was significantly decreased in the malignant group ( p < 0.01). The correlation between E6, E7, Sp1, and hTERC expression was positive but was negative with LKB1 ( p < 0.01). Our results also showed that HPV16 E6/E7 downregulated the expression of LKB1 at both the protein and mRNA levels. The loss of LKB1 upregulated Sp1 expression, and also promoted Sp1 activity. Sp1 further upregulated hTERC at the mRNA and gene amplification levels. Thus, we proposed a HPV–LKB1–Sp1–hTERC axis of E6/E7 upregulation of hTERC expression. Conclusion: We demonstrated for the first time that E6 and E7 promoted hTERC mRNA expression and the amplification of hTERC by relieving the effect of LKB1 on the phosphorylation of Sp1. Sp1 further activated hTERC by directly binding to the promoter regions of hTERC.


2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Weiwei Gong ◽  
Yueyang Liu ◽  
Eleftherios P. Diamandis ◽  
Marion Kiechle ◽  
Holger Bronger ◽  
...  

Abstract Background High-grade serous ovarian cancer (HGSOC) is the most common and lethal subtype of ovarian cancer. A growing body of evidence suggests tumor-supporting roles of several members of the kallikrein-related peptidase (KLK) family, including KLK5 and KLK7, in this cancer subtype. In normal physiology, KLK5 and KLK7 are the major proteases involved in skin desquamation. Moreover, in several cancer types KLK5 and KLK7 co-expression has been observed. Recently, we have shown that elevated KLK5 mRNA levels are associated with an unfavorable prognosis in HGSOC. Therefore, the aim of this study was to investigate the clinical significance of KLK7 mRNA expression and to explore its relation to KLK5 levels in HGSOC. Methods mRNA expression levels of KLK7 were quantified by qPCR in a well-characterized patient cohort afflicted with advanced high-grade serous ovarian cancer (FIGO III/IV, n = 139). Previously determined KLK5 mRNA as well as KLK5 and KLK7 antigen concentrations were used to evaluate the relationship between the expression patterns of both factors on the mRNA as well as protein level in tumor tissue of HGSOC patients. Results There were strong, significant positive correlations between KLK5 and KLK7 both at the mRNA and the protein level, suggesting coordinate expression of these proteases in HGSOC. In univariate analyses, elevated KLK7 levels as well as the combination of KLK5 + KLK7 (high and/or high versus low/low) were significantly associated with worse progression-free survival (PFS). High mRNA expression levels of KLK7 and the combination of KLK5 and KLK7 showed a trend towards significance for overall survival (OS). In multivariate analyses, KLK7 mRNA expression represented an unfavorable, statistically significant independent predictor for PFS and OS. Conclusions The findings imply that both increased KLK5 and KLK7 mRNA expression levels represent unfavorable prognostic biomarkers in advanced high-grade serous ovarian cancer, whereby multivariate analyses indicate that KLK7 mRNA exhibits a stronger predictive value as compared to KLK5 mRNA and the combination of KLK5 and KLK7.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3481-3481
Author(s):  
Ajay Abraham ◽  
Savitha Varatharajan ◽  
Ashok kumar Jayavelu ◽  
Shaji R Velayudhan ◽  
Rayaz Ahmed ◽  
...  

Abstract Abstract 3481 Wide inter-individual variation in terms of treatment outcome and toxic side effects of treatment exist among patients with AML receiving chemotherapy with cytarabine (ara-C) and daunorubicin. The pre-requisite for the cytotoxic action of pro-drug Ara-C is the enzymatic conversion to its active tri-phosphorylated form ara-CTP. Many drug activating (Deoxycytidine kinase (dCK) and human Equilibrative Nucleoside Transporter 1 (hENT1) and deactivating (Cytidine deaminase (CDA), 5'nucleotidase (NT5C2) genes and ribonucleoside reductase (RRM1), which are involved in transport and biotransformation of cytarabine contribute to the variation in ara-C sensitivity in AML patients. FLT3-ITD and NPM1 mutations act as major poor and good prognostic markers respectively in cytogenetically normal AML. The effect of these mutations in ara-C metabolism remains to be elucidated. The present study aims to determine independent as well as the combined effect of ara-C metabolizing genes mRNA expression on in-vitro ara-C cytotoxicity and the role of FLT3-ITD and NPM mutations on mRNA expression of these genes. Diagnostic bone marrow sample (median blasts 65%; range 21 – 98%) from 98 adult patients with de novo AML (other than AML-M3) were included in this study. mRNA expression levels for each target gene relative to housekeeping gene GAPDH was analyzed using Taqman based gene expression assays. In vitro cytotoxicity was assessed using MTT cell viability assay and IC-50 was calculated. In vitro sensitivity or resistance was classified on the basis of the IC-50 values <6uM and >6uM ara-C respectively. FLT3 ITD and NPM mutation status at diagnosis were determined through PCR followed by Genescan analysis using genomic DNA samples. Type of NPM mutation was identified by sequencing. When ara-C IC-50 values were compared with the mRNA expression levels of these candidate genes, Ara-C sensitive samples (n= 30; IC-50 < 6uM) showed significantly higher mRNA expression of dCK and hENT1 compared to those with Ara-C resistance (n=51) IC50 >6uM (median 314 (61.56 – 1232) vs. 180 (31.87 – 749.2); p = 0.0004 and median 172.1 (44.12 – 657.6) vs. 96.19 (37.49 – 432.4), p= 0.0008 respectively. RRM1 and NT5C2 did not show any association with in vitro Ara-C cytotoxicity, while CDA showed a trend towards association with lower CDA expression in ara-C sensitive samples. Based on these findings we put forward Ara-C resistance index (RI). RI is calculated by the formula RI = ΔCT (dCK X ENT1)/ ΔCT CDA. (Smaller ΔCT value= higher mRNA expression). RI values were significantly higher in resistant (IC50 >6uM) compared to sensitive cells (median: 6.084; range 1.89–11.82) vs. 3.702 (1.89–9.80); p=<0.0001). This association should now be validated in an independent cohort. Effects of NPM and FLT3 mutation status on Ara-C metabolizing genes were then evaluated. No significant association was found between FLT3-ITD status and the mRNA expression of these candidate genes. Interestingly, dCK mRNA levels were significantly higher in samples with NPM mutation (n=39) compared to NPM wild type (n=59); median 272.3 (41.64–1232) vs. 188.6 (31.87–1030); p value= 0.01. When analysed separately, patients with NPM type A mutation (n=27) showed significantly higher dCK expression (median 347.4 (41.64–1232) vs. 188.6 (31.87–1030); p value= 0.003 compared to those with wild type NPM1. This first report showing an association between expression profiles of ara-C metabolizing genes and NPM mutation should form the basis for evaluating their clinical correlations. Disclosures: No relevant conflicts of interest to declare.


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