Regulation of transthyretin by thyroid hormones in fish

Effects of cortisol and thyroid hormone on peripheral outer ring deiodination and osmoregulatory parameters in the Senegalese sole (Solea senegalensis)

“…There are very few reports on the use of slow-release thyroid hormone implants in fishes. Morgado et al (2007) used coconut oil to treat gilthead seabream (S. auratus) with a dose of 1 mg T 3 /g body weight, resulting in a 25-fold increased T 3 plasma concentration. We found a similar 27-fold increase using a dose of 2 mg T 3 /g.…”

“…Moreover, thyroid hormone economy is complicated by the presence of specific thyroid hormone-binding proteins that facilitate vectorial plasma transport (reviewed by Klaren et al (2007a)). Morgado et al (2007) have shown that treatment of S. auratus with T 3 increases the plasma concentration of the thyroid hormone-binding protein transthyretin ca. threefold.…”

“…The use of coconut oil as a vehicle for i.p. hormonal implants has been shown to be an effective and practical method to raise plasma cortisol or thyroid hormone levels in different teleost species (Laiz-Carrión et al 2003, Morgado et al 2007. Nine fish did not receive any treatment and served as the pre-injection group.…”

Waterborne exposure to PFOS causes disruption of the hypothalamus–pituitary–thyroid axis in zebrafish larvae

“…Several environmental contaminants, due to their structural resemblance to THs (e.g., some metabolites and derivatives of PCBs and phenol compounds), may affect circulating TH levels by competing for their binding sites at transport proteins and interfering with TH homeostasis by binding TTR in vertebrates (Yamauchi et al, 2003;Boas et al, 2006;Morgado et al, 2007). Therefore, chemicals that interfere with TH binding to TTR may directly affect the free concentration of plasma THs and the plasma clearance rate of THs in fish.…”

Bioconcentration and metabolism of decabromodiphenyl ether (BDE-209) result in thyroid endocrine disruption in zebrafish larvae

“…The nitrocellulose membrane was blocked for 1 h with 5% non-fat dried milk in tris-buffered saline (TBS) and incubated with primary antibody against TG (Sigma, St. Louis, MO, USA)/TTR (Abcam, USA) at 37 • C for 2 h. The blots were washed six times for 30 min with tris-buffered saline Tween-20 (TBST) and then incubated with AP-conjugated secondary antibody at 37 • C for 1 h. After that the blots were washed six times again, they were developed using a BCIP/NBT Kit (AMRESCO, USA). TTR is considered as an evolutionarily conserved serum protein (Hennebry et al, 2006;Buxbaum and Reixach, 2009 (Morgado et al, 2007). Using a rabbit antihuman TG serum that cross-reacted with lampreys (Lampetra appendix) TG, Western blotting detected a single protein of ∼226 kDa (Manzon and Youson, 2002).…”