scholarly journals Selenium status affects selenoprotein expression, reproduction, and F1 generation locomotor activity in zebrafish (Danio rerio)

2014 ◽  
Vol 111 (11) ◽  
pp. 1918-1931 ◽  
Author(s):  
Sam Penglase ◽  
Kristin Hamre ◽  
Josef D. Rasinger ◽  
Staale Ellingsen

Se is an essential trace element, and is incorporated into selenoproteins which play important roles in human health. Mammalian selenoprotein-coding genes are often present as paralogues in teleost fish, and it is unclear whether the expression patterns or functions of these fish paralogues reflect their mammalian orthologues. Using the model species zebrafish (Danio rerio; ZF), we aimed to assess how dietary Se affects key parameters in Se metabolism and utilisation including glutathione peroxidase (GPX) activity, the mRNA expression of key Se-dependent proteins (gpx1a, gpx1b, sepp1a and sepp1b), oxidative status, reproductive success and F1 generation locomotor activity. From 27 d until 254 d post-fertilisation, ZF were fed diets with graded levels of Se ranging from deficient ( < 0·10 mg/kg) to toxic (30 mg/kg). The mRNA expression of gpx1a and gpx1b and GPX activity responded in a similar manner to changes in Se status. GPX activity and mRNA levels were lowest when dietary Se levels (0·3 mg/kg) resulted in the maximum growth of ZF, and a proposed bimodal mechanism in response to Se status below and above this dietary Se level was identified. The expression of the sepp1 paralogues differed, with only sepp1a responding to Se status. High dietary Se supplementation (30 mg/kg) decreased reproductive success, while the offspring of ZF fed above 0·3 mg Se/kg diet had lower locomotor activity than the other groups. Overall, the novel finding of low selenoprotein expression and activity coinciding with maximum body growth suggests that even small Se-induced variations in redox status may influence cellular growth rates.

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Birhan Alemnew ◽  
Soren T. Hoff ◽  
Tamrat Abebe ◽  
Markos Abebe ◽  
Abraham Aseffa ◽  
...  

Abstract Background Understanding immune mechanisms, particularly the role of innate immune markers during latent TB infection remains elusive. The main objective of this study was to evaluate mRNA gene expression patterns of toll-like receptors (TLRs) as correlates of immunity during latent TB infection and further infer their roles as potential diagnostic biomarkers. Methods Messenger RNA (mRNA) levels were analysed in a total of 64 samples collected from apparently healthy children and adolescents latently infected with tuberculosis (n = 32) or non-infected (n = 32). Relative expression in peripheral blood of selected genes encoding TLRs (TLR-1, TLR-2, TLR-4, TLR-6 and TLR-9) was determined with a quantitative real-time polymerase chain reaction (qRT-PCR) using specific primers and florescent labelled probes and a comparative threshold cycle method to define fold change. Data were analysed using Graph-Pad Prism 7.01 for Windows and a p-value less than 0.05 was considered statistically significant. Results An increased mean fold change in the relative expression of TLR-2 and TLR-6 mRNA was observed in LTBI groups relative to non-LTBI groups (p < 0.05), whereas a slight fold decrease was observed for TLR-1 gene. Conclusions An increased mRNA expression of TLR-2 and TLR-6 was observed in latently infected individuals relative to those non-infected, possibly indicating the roles these biomarkers play in sustenance of the steady state interaction between the dormant TB bacilli and host immunity.


2008 ◽  
Vol 100 (4) ◽  
pp. 2015-2025 ◽  
Author(s):  
Julie E. Miller ◽  
Elizabeth Spiteri ◽  
Michael C. Condro ◽  
Ryan T. Dosumu-Johnson ◽  
Daniel H. Geschwind ◽  
...  

Cognitive and motor deficits associated with language and speech are seen in humans harboring FOXP2 mutations. The neural bases for FOXP2 mutation-related deficits are thought to reside in structural abnormalities distributed across systems important for language and motor learning including the cerebral cortex, basal ganglia, and cerebellum. In these brain regions, our prior research showed that FoxP2 mRNA expression patterns are strikingly similar between developing humans and songbirds. Within the songbird brain, this pattern persists throughout life and includes the striatal subregion, Area X, that is dedicated to song development and maintenance. The persistent mRNA expression suggests a role for FoxP2 that extends beyond the formation of vocal learning circuits to their ongoing use. Because FoxP2 is a transcription factor, a role in shaping circuits likely depends on FoxP2 protein levels which might not always parallel mRNA levels. Indeed our current study shows that FoxP2 protein, like its mRNA, is acutely downregulated in mature Area X when adult males sing with some differences. Total corticosterone levels associated with the different behavioral contexts did not vary, indicating that differences in FoxP2 levels are not likely attributable to stress. Our data, together with recent reports on FoxP2's target genes, suggest that lowered FoxP2 levels may allow for expression of genes important for circuit modification and thus vocal variability.


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.


2013 ◽  
Vol 31 (4_suppl) ◽  
pp. 383-383
Author(s):  
Martin K. H. Maus ◽  
Craig Stephens ◽  
Stephanie H. Astrow ◽  
Peter Philipp Grimminger ◽  
Dongyun Yang ◽  
...  

383 Background: Gene expression levels of ERCC1, TS, EGFR and VEGFR2 may have predictive value for the personalized use of standard chemotherapeutics as well as agents targeting the EGFR and VEGF pathways and the efficacy of EGFR directed monoclonal antibodies like panitumumab and cetuximab has been confirmed to be dependent on wt KRAS and wt BRAF in patients with advanced colorectal cancer. We investigated the correlations between KRAS/BRAF mutational status and the mRNA expression levels of these genes. Methods: Formalin-fixed paraffin-embedded tumor specimens from 600 patients with advanced colorectal adenocarcinoma were microdissected and DNA and RNA was extracted. Specifically designed primers and probes were used to detect 7 different base substitutions in codon 12 and 13 of KRAS, V600E mutations in BRAF and the expression levels of ERCC1, TS, EGFR and VEGFR2 by RT-PCR. Results: Mt KRAS tumors had significantly lower TS and EGFR gene expression levels compared with wt KRAS (p<0,001), whereas mt BRAF tumors showed significantly increased TS and EGFR mRNA levels compared to wt BRAF (p<0,001). Mt BRAF tumors showed significantly higher mRNA levels than mt KRAS tumors (p<0,001). ERCC1 and VEGFR2 mRNA levels were significantly down-regulated in mt KRAS specimen (p<0,001), but showed no significant correlation with BRAF mutational status. Conclusions: KRAS and BRAF mutations are associated with opposite mRNA expression levels for TS and EGFR. Recently, resistance to BRAF inhibition in mt BRAF colorectal tumors has been shown in preclinical models to be associated with up-regulation of EGFR. Our data suggests that BRAF mutants are associated with high EGFR levels at the time of diagnosis, and not necessarily part of an acquired mechanism of resistance. Significantly lower mRNA expression levels of VEGFR2 in mt KRAS tumors may explain lower response to angiogenesis inhibition seen in the TML study.


2001 ◽  
Vol 69 (3) ◽  
pp. 1420-1427 ◽  
Author(s):  
Brian K. Coombes ◽  
James B. Mahony

ABSTRACT Strong epidemiological and pathological evidence supports a role for Chlamydia pneumoniae infection in atherosclerosis and human coronary heart disease. Animal models have shown that C. pneumoniae disseminates hematogenously in infected monocytes and macrophages, while in vitro data suggest that infected macrophages can transmit C. pneumoniae infection directly to endothelial cells. Endothelial cells may be key in vivo targets for C. pneumoniae infection; given that these cells are important in regulating the dynamics of the vessel wall, we used cDNA microarrays to study the transcriptional response of endothelial cells to infection with C. pneumoniae. cDNA arrays were used to characterize the mRNA expression profiles for 268 human genes following infection with C. pneumoniae, which were compared to mRNA profiles of uninfected cells. Selected genes of interest were further investigated by reverse transcription-PCR throughout a 24-h period of infection. C. pneumoniaeinfection upregulated mRNA expression for approximately 20 (8%) of the genes studied. Genes coding for cytokines (interleukin-1), chemokines (monocyte chemotactic protein 1 and interleukin-8), and cellular growth factors (heparin-binding epidermal-like growth factor, basic fibroblast growth factor, and platelet-derived growth factor B chain) were the most prominently upregulated. In addition to these families of genes, increases in mRNA levels for intracellular kinases and cell surface receptors with signal transduction activities were observed. Time course experiments showed that mRNA levels were upregulated within 2 h following infection. These results expand our knowledge of the response of endothelial cells to C. pneumoniae by further defining the repertoire of C. pneumoniae-inducible genes and provide new insight into potential mechanisms of atherogenesis. In addition, the use of cDNA microarrays may prove useful for the study of host cell responses to C. pneumoniae infection during latent and replicative stages of infection and related pathology.


Reproduction ◽  
2011 ◽  
Vol 142 (6) ◽  
pp. 855-867 ◽  
Author(s):  
Hollian R Phillipps ◽  
Ilona C Kokay ◽  
David R Grattan ◽  
Peter R Hurst

X-linked inhibitor of apoptosis protein (XIAP) interacts with caspases to inhibit their activity, thereby providing a potential mechanism for regulation of granulosa cell apoptosis occurring during follicular atresia. The aim of this study was to determine the presence and localization of XIAP mRNA and protein content in the sheep ovary and compare these expression patterns with active caspase-3 protein in the same antral follicles. Romney ewe estrous cycles (n=25) were synchronized with 2–3 Estrumate injections and ovarian tissue collected during the luteal and follicular phases of the cycle. The presence ofXIAPmRNA was confirmed by RT-PCR using laser capture microdissected ovarian cell samples.XIAPmRNA was subsequently localized byin situhybridization histochemistry and XIAP and active caspase-3 protein visualized by immunohistochemistry. In antral follicles extensive XIAP localization was evident in both granulosa and thecal cells. In contrast, mRNA expression was widespread in granulosa cells and only detected in thecal tissue from a small proportion of antral follicles. Active caspase-3 and XIAP comparative expression analysis showed positiveXIAPmRNA expression in all late luteal phase (day 14) follicles, despite varying levels of active caspase-3 protein. A proportion of follicular phase (days 15 and 16) follicles, however, showed an inverse expression relationship at the protein and mRNA levels in both granulosa and thecal tissue, as did XIAP protein in day 14 follicles. These results suggest high XIAP may prevent activation of caspase-3, thereby regulating follicular atresia in antral follicles and could potentially be utilized as a marker of follicular health.


2007 ◽  
Vol 196 (3) ◽  
pp. 519-528 ◽  
Author(s):  
Sylvia V H Grommen ◽  
Lutgarde Arckens ◽  
Tim Theuwissen ◽  
Veerle M Darras ◽  
Bert De Groef

In this study, we tried to elucidate the changes in thyroid hormone (TH) receptor β2 (TRβ2) expression at the different levels of the hypothalamo–pituitary–thyroidal (HPT) axis during the last week of chicken embryonic development and hatching, a period characterized by an augmented activity of the HPT axis. We quantified TRβ2 mRNA in retina, pineal gland, and the major control levels of the HPT axis – brain, pituitary, and thyroid gland – at day 18 of incubation, and found the most abundant mRNA content in retina and pituitary. Thyroidal TRβ2 mRNA content increased dramatically between embryonic day 14 and 1 day post-hatch. In pituitary and hypothalamus, TRβ2 mRNA expression rose gradually, in parallel with increases in plasma thyroxine concentrations. Using in situ hybridization, we have demonstrated the presence of TRβ2 mRNA throughout the diencephalon and confirmed the elevation in TRβ2 mRNA expression in the hypophyseal thyrotropes. In vitro incubation with THs caused a down-regulation of TRβ2 mRNA levels in embryonic but not in post-hatch pituitaries. The observed expression patterns in pituitary and diencephalon may point to substantial changes in TRβ2-mediated TH feedback active during the perinatal period. The strong rise in thyroidal TRβ2 mRNA content could be indicative of an augmented modulation of thyroid development and/or function by THs toward and after hatching. Finally, THs proved to exert an age-dependent effect on pituitary TRβ2 mRNA expression.


2009 ◽  
Vol 297 (4) ◽  
pp. R988-R997 ◽  
Author(s):  
S. F. Perry ◽  
B. Vulesevic ◽  
M. Grosell ◽  
M. Bayaa

Experiments were performed to test the hypothesis that three members of the SLC26 anion transporter gene family (SLC26a3, A4, and A6; hereafter termed za3, za4, and za6) mediate branchial Cl−/HCO3− exchange in adult zebrafish ( Danio rerio). Real-time RT-PCR demonstrated that the gill expressed relatively high levels of za6 mRNA; za3 and za4 mRNA, while present, were less abundant. Also, za4 and za6 were expressed at relatively high levels in the kidney. The results of in situ hybridization or immunocytochemistry (za3 only) experiments performed on gill sections revealed that the SLC26 transporters were predominantly expressed on the filament epithelium (especially within the interlamellar regions) and to a lesser extent on the lamellar epithelium at the base of lamellae. This distribution pattern suggests that the SLC26 anion transporters are localized to mitochondrion-rich cells (ionocytes). Transferring fish to water containing low [Cl−] (0.02 mmol/l) resulted in significant increases in branchial SLC26 mRNA expression after 5–10 days of exposure relative to fish raised in normal water [Cl−] (0.4 mmol/l); transferring fish to Cl−-enriched water (2.0 mmol/l) was without effect on mRNA levels. Transferring fish to water containing elevated levels of NaHCO3 (10–12.5 mmol/l) caused marked increases in branchial SLC26 mRNA expression between 3 and 10 days of transfer that was associated with a significant 40% increase in Cl− uptake (as measured upon return to normal water after 7 days). A decrease in whole body net acid excretion (equivalent to an increase in net base excretion) in fish previously maintained in high [NaHCO3] water, concurrent with increases in Cl− uptake and SLC26 mRNA levels, suggests a role for these anion transporters in Cl− uptake and acid-base regulation owing to their Cl−/HCO3− exchange activities.


Endocrinology ◽  
2011 ◽  
Vol 152 (3) ◽  
pp. 989-1000 ◽  
Author(s):  
Monika Proszkowiec-Weglarz ◽  
Stacy E. Higgins ◽  
Tom E. Porter

The anterior pituitary gland plays an important role in the regulation of many physiological processes. Formation of Rathke's pouch (RP), the precursor of the anterior pituitary, involves evagination of the oral ectoderm in a multi-step process regulated by cell interactions, signaling pathways, and transcription factors. Chickens are an excellent model to study development because of the availability of large sample sizes, accurate timing of development, and embryo accessibility. The aim of this study was to quantify mRNA expression patterns in the developing chicken anterior pituitary to evaluate the chicken embryo as a model for mammalian pituitary development. The expression profiles of 16 genes differentially expressed in RP and neuroectoderm were determined in this study. Among these, Pitx1, Pitx2, and Hesx1 mRNA levels were high on embryonic days (e) 2.5 to e3 in RP and decreased during development. Expression of Pit1 and Tbx19 mRNA in RP reached the highest levels by e7 and e6.5, respectively. Levels of glycoprotein subunit α mRNA increased beginning at e4. FGF8 mRNA showed the highest expression at e3 to e3.5 in neuroectoderm. BMP2 showed slight decreases in mRNA expression in both tissues during development, while Isl1 and Noggin mRNA expression increased in later development. Taken together, we present the first quantitative transcriptional profile of pituitary organogenesis. Our results will help further understanding of the functional development of this gland. Moreover, because of the high similarity in gene expression patterns observed between chicken and mouse, chickens could serve as an excellent model to study genetic and molecular mechanisms underlying pituitary development.


2005 ◽  
Vol 20 (1) ◽  
pp. 18-27 ◽  
Author(s):  
G. Soufla ◽  
S. Baritaki ◽  
S. Sifakis ◽  
A. Zafiropoulos ◽  
D.A. Spandidos

Deregulation of the apoptotic machinery plays a major role in cell death, cellular transformation and cancer. p53, Bcl-2, Bcl-XL, Bax and Mdm2 mRNA expression patterns were evaluated in tissue samples with cervical intraepithelial neoplasia (CIN) and cervical cancer compared to those of normal cervical tissues, and correlated with the underlying cervical lesions. Transcript levels of the above genes were assessed by RT-PCR analysis in a total of 44 cervical specimens. p53, Bcl-2, Bax and Mdm2 transcript levels were significantly different in the normal, CIN and cancer specimen groups (p=0.003, p=0.009, p=0.040 and p=0.001, respectively). Specifically, p53, Bax and Bcl-2 exhibited substantially lower transcript levels in CIN lesions compared to controls, whereas Bax mRNA levels showed a significant decrease in cancer compared to normal specimens. Mdm2 mRNA expression was considerably lower in cancer than in CIN lesions or normal cervix. High-grade squamous intraepithelial lesions exhibited lower p53 and Bcl-2 mRNA levels than controls (p=0.002, p=0.016). Coexpression analysis revealed more correlations between the above apoptosis-related molecules in normal tissues compared to CIN or cancer specimens. p53 showed significant coexpression with Bax, Bcl-2 and Mdm2 (p=0.040, p=0.013 and p=0.015, respectively) in normal cervical specimens. Bax and Bcl-XL mRNA expression was negatively correlated. Mdm2 transcriptional levels correlated significantly with those of Bax, Bcl-XL and Bcl-2. Our findings show that p53, Bax, Bcl-2 and Mdm2 mRNA expression levels correlate with the malignant transformation of the uterine cervix. mRNA coexpression patterns of the members of the pro- and anti-apoptotic family examined in cervical carcinogenesis were found to be disrupted in CIN and cancer, as already demonstrated at the protein level.


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