scholarly journals Knockout of the Glucocorticoid Receptor Impairs Reproduction in Female Zebrafish

2020 ◽  
Vol 21 (23) ◽  
pp. 9073
Author(s):  
Francesca Maradonna ◽  
Giorgia Gioacchini ◽  
Valentina Notarstefano ◽  
Camilla Maria Fontana ◽  
Filippo Citton ◽  
...  
Keyword(s):  
Glucocorticoid Receptor ◽  
Infrared Imaging ◽  
Fertilization Rate ◽  
Strong Increase ◽  
Mrna Levels ◽  
Reproductive Process ◽  
Zona Radiata ◽  
Fourier Transform Infrared Imaging ◽  
Abundance And Distribution ◽  
Female Zebrafish

The pleiotropic effects of glucocorticoids in metabolic, developmental, immune and stress response processes have been extensively investigated; conversely, their roles in reproduction are still less documented. It is well known that stress or long-lasting therapies can cause a strong increase in these hormones, negatively affecting reproduction. Moreover, the need of glucocorticoid (GC) homeostatic levels is highlighted by the reduced fertility reported in the zebrafish glucocorticoid receptor mutant (nr3c1ia30/ia30) line (hereafter named gr−/−). Starting from such evidence, in this study, we have investigated the role of glucocorticoid receptor (Gr) in the reproduction of female zebrafish. Key signals orchestrating the reproductive process at the brain, liver, and ovarian levels were analyzed using a multidisciplinary approach. An impairment of the kiss-GnRH system was observed at the central level in (gr−/−) mutants as compared to wild-type (wt) females while, in the liver, vitellogenin (vtg) mRNA transcription was not affected. Changes were instead observed in the ovary, particularly in maturing and fully grown follicles (classes III and IV), as documented by the mRNA levels of signals involved in oocyte maturation and ovulation. Follicles isolated from gr−/− females displayed a decreased level of signals involved in the acquisition of competence and maturation, causing a reduction in ovulation with respect to wt females. Fourier transform infrared imaging (FTIRI) analysis of gr−/− follicle cytoplasm showed major changes in macromolecule abundance and distribution with a clear alteration of oocyte composition. Finally, differences in the molecular structure of the zona radiata layer of gr−/− follicles are likely to contribute to the reduced fertilization rate observed in mutants.

scholarly journals Sesamin Modulates Tyrosine Hydroxylase, Superoxide Dismutase, Catalase, Inducible No Synthase and Interleukin-6 Expression in Dopaminergic Cells Under Mpp+-Induced Oxidative Stress

2008 ◽  
Vol 1 (1) ◽  
pp. 54-62 ◽  
Author(s):  
Vicky Lahaie-Collins ◽  
Julie Bournival ◽  
Marilyn Plouffe ◽  
Julie Carange ◽  
Maria-Grazia Martinoli
Keyword(s):  
Oxidative Stress ◽  
Superoxide Dismutase ◽  
Tyrosine Hydroxylase ◽  
Protein Expression ◽  
Pc12 Cells ◽  
Interleukin 6 ◽  
Estrogen Receptor Alpha ◽  
Strong Increase ◽  
Mrna Levels ◽  
Neuronal Pc12 Cells

Oxidative stress is regarded as a mediator of nerve cell death in several neurodegenerative disorders, such as Parkinson's disease. Sesamin, a lignan mainly found in sesame oil, is currently under study for its anti-oxidative and possible neuroprotective properties. We used 1-methyl-4-phenyl-pyridine (MPP+) ion, the active metabolite of the potent parkinsonism-causing toxin 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine, to produce oxidative stress and neurodegeneration in neuronal PC12 cells, which express dopamine, as well as neurofilaments. Our results show that picomolar doses of sesamin protected neuronal PC12 cells from MPP+-induced cellular death, as revealed by colorimetric measurements and production of reactive oxygen species. We also demonstrated that sesamin acted by rescuing tyrosine hydroxylase levels from MPP+-induced depletion. Sesamin, however, did not modulate dopamine transporter levels, and estrogen receptor-alpha and -beta protein expression. By examining several parameters of cell distress, we found that sesamin also elicited a strong increase in superoxide dismutase activity as well as protein expression and decreased catalase activity and the MPP+stimulated inducible nitric oxide synthase protein expression, in neuronal PC12 cells. Finally, sesamin possessed significant anti-inflammatory properties, as disclosed by its potential to reduce MPP+-induced interleukin-6 mRNA levels in microglia. From these studies, we determined the importance of the lignan sesamin as a neuroprotective molecule and its possible role in complementary and/or preventive therapies of neurodegenerative diseases.

Spaceflight modulates insulin-like growth factor binding proteins and glucocorticoid receptor in osteoblasts

1998 ◽  
Vol 85 (1) ◽  
pp. 139-147 ◽  
Author(s):  
Yasuhiro Kumei ◽  
Hitoyata Shimokawa ◽  
Hisako Katano ◽  
Hideo Akiyama ◽  
Masahiko Hirano ◽  
...  
Keyword(s):  
Growth Factor ◽  
Glucocorticoid Receptor ◽  
Space Shuttle ◽  
Mrna Levels ◽  
Insulin Like Growth Factor ◽  
Factor Binding ◽  
Dihydroxyvitamin D ◽  
Protein Levels ◽  
Glucocorticoid Receptor Mrna ◽  
Cellular Dna

Rat osteoblasts were cultured for 4 or 5 days during a Space Shuttle mission. After 20-h treatment with 1α,25-dihydroxyvitamin D3, conditioned media were harvested and cellular DNA and/or RNA were fixed on board. The insulin-like growth factor binding protein (IGF BP)-3 levels in the media were three- and tenfold higher than in ground controls on the fourth and fifth flight days, as quantitated by Western ligand blotting and radioimmunoassay, respectively. The increased IGF BP-3 protein levels correlated with two- to threefold elevation of IGF BP-3 mRNA levels, obtained by reverse transcription-polymerase chain reaction. The IGF BP-5 mRNA levels in flight cultures were 33–69% lower than in ground controls. The IGF BP-4 mRNA levels in flight cultures were 75% lower than in ground controls on the fifth day but were not different on the fourth day. The glucocorticoid receptor mRNA levels in flight cultures were increased by three- to eightfold on the fourth and fifth days compared with levels in ground controls. These data suggest potential mechanisms underlying spaceflight-induced osteopenia.

Determinants of leptin gene expression in fat depots of lean mice

2002 ◽  
Vol 282 (1) ◽  
pp. R226-R234 ◽  
Author(s):  
Yiying Zhang ◽  
Kai-Ying Guo ◽  
Patricia A. Diaz ◽  
Moonseong Heo ◽  
Rudolph L. Leibel
Keyword(s):  
Gene Expression ◽  
Glucocorticoid Receptor ◽  
Insulin Receptor ◽  
Physiological Role ◽  
Mrna Levels ◽  
Strongly Correlated ◽  
Fat Depots ◽  
Tnf Α ◽  
Adipocyte Volume

The relationship of leptin gene expression to adipocyte volume was investigated in lean 10-wk-old male C57BL/6J mice. mRNA levels for leptin, insulin receptor, glucocorticoid receptor, and tumor necrosis factor (TNF)-α in inguinal, epididymal, and retroperitoneal adipose tissues were quantified and related to adipocyte volume. Leptin mRNA levels were highly correlated with adipocyte volume within each fat depot. Multiple regression analysis of pooled data from the three depots showed that leptin mRNA levels were strongly correlated with adipocyte volumes (β = 0.84, P < 0.001) and, to a smaller degree, with glucocorticoid receptor mRNA levels (β = 0.36, P < 0.001). Depot of origin had no effect ( P > 0.9). Rates of leptin secretion in vitro were strongly correlated with leptin mRNA levels ( r = 0.89, P < 0.001). mRNA levels for TNF-α, insulin receptor, and glucocorticoid receptor showed no significant correlation with adipocyte volume. These results demonstrate that depot-specific differences in leptin gene expression are mainly related to the volumes of the constituent adipocytes. The strong correlation between leptin gene expression and adipocyte volume supports leptin's physiological role as a humoral signal of fat mass.

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