title: Inhibitory effects of 2-iodohexadecanal on FRTL-5 thyroid cells proliferation.
abstract: Although thyroid gland function is mainly under the control of pituitary TSH, other factors, such as iodine, play a role in this process. The thyroid is capable of producing different iodolipids such as 6-iodo-deltalactone and 2-iodohexadecanal (2-IHDA). It was shown that these iodolipids mimic some of the inhibitory effects of excess iodide on several thyroid parameters.
  
  
  OBJECTIVE
  To study the effect of 2-IHDA on cell proliferation and apoptosis in FRTL-5 cells.
  
  
  RESULTS
  FRTL-5 cells were grown in the presence of TSH and treated with increasing concentrations of KI and 2-IHDA (0.5, 5, 10 and 33 µM) for 24, 48 and 72 h. Whereas KI inhibited cell proliferation only at 33 µM after 72 h of treatment, 2-IHDA inhibited in a time and concentration dependent manner. Analysis of cell cycle by flow cytometric DNA analysis revealed an accumulation of cells in G1 phase induced by 2-IHDA. The expression of cyclin A, cyclin D1 and cyclin D3 were reduced after treatment with 2-IHDA whereas CDK4 and CDK6 proteins were not modified. 2-IHDA induced a dynamic change in cytoplasmic to nuclear accumulation of p21 and p27 causing these proteins to be accumulated mostly in the nucleus. We also observed evidence of a pro-apoptotic effect of 2-IHDA at highest concentrations. No significant effect of KI was observed.
  
  
  CONCLUSIONS
  These results suggest that the inhibitory effects of 2-IHDA on FRTL-5 thyroid cell proliferation are mediated by cell cycle arrest in G1/S phase and cell death by apoptosis.
authors: Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina.
authors: Lisa
authors: L
authors: Thomasz
authors: I.R.I.B.H.M., Université Libre de Bruxelles, Bruxelles, Belgium.
authors: Katia
authors: K
authors: Coulonval
authors: Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina.
authors: Leonardo
authors: L
authors: Salvarredi
authors: Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina.
authors: Romina
authors: R
authors: Oglio
authors: IEOS, Università degli Studi di Napoli "Federico II", Naples, Italy.
authors: Alfredo
authors: A
authors: Fusco
authors: Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina.
authors: Luciano
authors: L
authors: Rossich
authors: Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina; Human Biochemistry, School of Medicine, University of Buenos Aires, Buenos Aires, Argentina.
authors: Mario A
authors: MA
authors: Pisarev
authors: I.R.I.B.H.M., Université Libre de Bruxelles, Bruxelles, Belgium.
authors: Pierre P
authors: PP
authors: Roger
authors: Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina. Electronic address: juvenal@cnea.gov.ar.
authors: Guillermo J
authors: GJ
authors: Juvenal
mesh_terms: D000447:Aldehydes / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis; D059447:Cell Cycle Checkpoints / Q000187:drug effects*; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D016213:Cyclins / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects; D051381:Rats; D013961:Thyroid Gland / Q000166:cytology* / Q000187:drug effects; D013972:Thyrotropin / Q000494:pharmacology*
chemical_list: D000447:Aldehydes; D016213:Cyclins; C065952:2-iodohexadecanal; D013972:Thyrotropin
keywords: Iodine; Iodohexadecanal; Iodolipids; Thyroid