Abstract
Disruption of thyroid hormone (TH) signaling can compromise vital processes both during development and in the adult. We previously reported on high-throughput screening experiments for man-made TH disruptors using a stably integrated line of rat pituitary cells, GH3.TRE-Luc, in which a thyroid hormone receptor (TR) response element drives luciferase (Luc) expression. In these experiments, several retinoid/rexinoid compounds activated the reporter. Here we show that all-trans and 13-cis retinoic acid appear to function through the heterodimer partners of TRs, retinoid-X receptors (RXRs), as RXR antagonists abrogated retinoid-induced activation. The retinoids also induced known endogenous TR target genes, showing good correlation with Luc activity. Synthetic RXR-specific agonists significantly activated all tested TR target genes, but interestingly, retinoid/rexinoid activation was more consistent between genes than the extent of T3-induced activation. In contrast, the retinoids neither activated the Luc reporter construct in transient transfection assays in the human hepatocarcinoma cell line HuH7, nor two of the same T3-induced genes examined in pituitary cells. These data demonstrate the suitability and sensitivity of GH3.TRE-Luc cells for screening chemical compound libraries for TH disruption and suggest that the extent of disruption can vary on a cell type and gene-specific bases, including an underappreciated contribution by RXRs.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1609-1618 |
| Number of pages | 10 |
| Journal | Toxicology in Vitro |
| Volume | 29 |
| Issue number | 7 |
| DOIs | |
| State | Published - Oct 1 2015 |
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Keywords
- Endocrine disruption
- Reporter gene assay
- Retinoids
- Rexinoids
- Thyroid hormone receptors
ASJC Scopus subject areas
- Toxicology
Cite this
Pituitary specific retinoid-X receptor ligand interactions with thyroid hormone receptor signaling revealed by high throughput reporter and endogenous gene responses. / Mengeling, Brenda J.; Furlow, John.
In: Toxicology in Vitro, Vol. 29, No. 7, 01.10.2015, p. 1609-1618.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Pituitary specific retinoid-X receptor ligand interactions with thyroid hormone receptor signaling revealed by high throughput reporter and endogenous gene responses
AU - Mengeling, Brenda J.
AU - Furlow, John
PY - 2015/10/1
Y1 - 2015/10/1
N2 - Disruption of thyroid hormone (TH) signaling can compromise vital processes both during development and in the adult. We previously reported on high-throughput screening experiments for man-made TH disruptors using a stably integrated line of rat pituitary cells, GH3.TRE-Luc, in which a thyroid hormone receptor (TR) response element drives luciferase (Luc) expression. In these experiments, several retinoid/rexinoid compounds activated the reporter. Here we show that all-trans and 13-cis retinoic acid appear to function through the heterodimer partners of TRs, retinoid-X receptors (RXRs), as RXR antagonists abrogated retinoid-induced activation. The retinoids also induced known endogenous TR target genes, showing good correlation with Luc activity. Synthetic RXR-specific agonists significantly activated all tested TR target genes, but interestingly, retinoid/rexinoid activation was more consistent between genes than the extent of T3-induced activation. In contrast, the retinoids neither activated the Luc reporter construct in transient transfection assays in the human hepatocarcinoma cell line HuH7, nor two of the same T3-induced genes examined in pituitary cells. These data demonstrate the suitability and sensitivity of GH3.TRE-Luc cells for screening chemical compound libraries for TH disruption and suggest that the extent of disruption can vary on a cell type and gene-specific bases, including an underappreciated contribution by RXRs.
AB - Disruption of thyroid hormone (TH) signaling can compromise vital processes both during development and in the adult. We previously reported on high-throughput screening experiments for man-made TH disruptors using a stably integrated line of rat pituitary cells, GH3.TRE-Luc, in which a thyroid hormone receptor (TR) response element drives luciferase (Luc) expression. In these experiments, several retinoid/rexinoid compounds activated the reporter. Here we show that all-trans and 13-cis retinoic acid appear to function through the heterodimer partners of TRs, retinoid-X receptors (RXRs), as RXR antagonists abrogated retinoid-induced activation. The retinoids also induced known endogenous TR target genes, showing good correlation with Luc activity. Synthetic RXR-specific agonists significantly activated all tested TR target genes, but interestingly, retinoid/rexinoid activation was more consistent between genes than the extent of T3-induced activation. In contrast, the retinoids neither activated the Luc reporter construct in transient transfection assays in the human hepatocarcinoma cell line HuH7, nor two of the same T3-induced genes examined in pituitary cells. These data demonstrate the suitability and sensitivity of GH3.TRE-Luc cells for screening chemical compound libraries for TH disruption and suggest that the extent of disruption can vary on a cell type and gene-specific bases, including an underappreciated contribution by RXRs.
KW - Endocrine disruption
KW - Reporter gene assay
KW - Retinoids
KW - Rexinoids
KW - Thyroid hormone receptors
UR - http://www.scopus.com/inward/record.url?scp=84936745567&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84936745567&partnerID=8YFLogxK
U2 - 10.1016/j.tiv.2015.06.018
DO - 10.1016/j.tiv.2015.06.018
M3 - Article
C2 - 26096596
AN - SCOPUS:84936745567
VL - 29
SP - 1609
EP - 1618
JO - Toxicology in Vitro
JF - Toxicology in Vitro
SN - 0887-2333
IS - 7
ER -