Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: KEGG:D02259 (NaI)
 1,823 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present studies have demonstrated the production of transforming growth factor-beta 1 (TGF-beta 1) by porcine thyroid follicular cells (TFCs) maintained in vitro as subconfluent monolayers, and have confirmed a stimulatory effect of iodide on thyroidal TGF-beta 1 mRNA and peptide release. RNA extracted from TFCs maintained in the absence of iodide contained a 2.5 kb transcript which hybridized specifically with a cDNA probe for human TGF-beta 1, and which showed an approximate doubling in intensity in cells exposed to 10 mumol NaI/1. In the presence of the anti-thyroid thionamide drug methimazole (MMI; 1 mmol/l), the action of iodide on TGF-beta 1 mRNA was attenuated, although MMI alone had no effect on the control level of TGF-beta 1 mRNA. The TGF-beta 1 peptide content of TFC-conditioned media (TFC-CM) was assessed using the fetal mink lung cell line Mv1Lu, in which activated TGF-beta 1 specifically suppresses trichloroacetic acid-precipitable [methyl-3H]thymidine incorporation. Newly conditioned TFC-CM stimulated [methyl-3H]thymidine incorporation into Mv1Lu cells, but after heat treatment to inactivate growth stimulators and activate the latent TGF-beta 1 component this medium inhibited [methyl-3H]thymidine incorporation. This inhibitory effect was prevented by immunoadsorption of TFC-CM with a TGF-beta 1-neutralizing antiserum, confirming the specificity of the inhibitory response. The inhibitory activity of TFC-CM was increased when the TFCs were preincubated with 10 mumol NaI/1, and lost when TFCs were exposed to MMI. In conclusion, TFCs produce TGF-beta 1 mRNA and TGF-beta 1 peptide, which are both increased by iodide treatment in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Transforming growth factor-beta 1 production in porcine thyroid follicular cells: regulation by intrathyroidal organic iodine. 147 6

The present study has investigated the relative levels and interconversion of latent and active forms of transforming growth factor-beta 1 (TGF-beta 1) in human thyroid follicular cell cultures derived from sporadic non-toxic goitres. Northern blotting of RNA extracted from 72-h cultures revealed a 2.5 kb mRNA transcript hybridizing with a cDNA probe for latent TGF-beta 1, the intensity of which was doubled in cells exposed to NaI (10 mumol/l). Radioreceptor assay of follicular cell-conditioned medium for TGF-beta 1 content confirmed a similar enhancing effect of iodide. The endogenous active component of TGF-beta 1 present in conditioned medium represented only a minor fraction of the total TGF-beta 1 content, this fraction was not enhanced by exposure of follicular cells to iodide. The low level of endogenous active TGF-beta 1 in medium conditioned by either control or iodide-treated cells was confirmed by immunoadsorption with a precipitating antiserum against active TGF-beta 1, when such cells failed to show a reversal of the iodide-induced decrease in [methyl-3H]thymidine incorporation into trichloroacetic acid-precipitable material. In contrast to the inhibitory effect of iodide on de novo DNA synthesis, which appeared not to reflect an increase in active TGF-beta 1, the inhibitory effects of plasminogen (100 mg/l) or plasmin (2000 U/l) on [methyl-3H]thymidine incorporation into thyroid cells were reversible by TGF-beta 1 immunoadsorption. This provides evidence that the plasmin-mediated inhibition of DNA synthesis in thyroid follicular cells may be attributed to the growth-regulating action of an increased level of activated TGF-beta 1.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Transforming growth factor-beta 1 synthesis in human thyroid follicular cells: differential effects of iodide and plasminogen on the production of latent and active peptide forms. 801