Growth Hormone treatment in children with idiopathic Short Stature: correlation of growth response with Peripheral Thyroid Hormone Action

SUSPERREGUY, S.; MUÑOZ, L.; TKALENKO, N.; MASCANFRONI, ID.; ALAMINO, VA.; MONTESINOS, M.; MASINI-REPISO, AM.; MIRAS, M.; PELLIZA, C.

Costa do Sauípe

Encuentro; XXI Annual Meeting. SLEP; 2010

Sociedad Latino-Americana de Endocrinología Pediátrica (SLEP)

Objective: GH treatment increases height in Idiopathic Short Stature (ISS), however growth rate differs among patients. Thyroid hormones (TH) are also essential for growth acting through TH receptors (TR) α and β. We reported that GH reduced peripheral TH action in Turner Syndrome. We aimed at assessing the effect of GH treatment in ISS on peripheral TH action and the correlation between thyroid status and growth response. Methods: 18 normal and 25 ISSwere evaluated before and after 12 months of life time (normal) or 12 months of GH therapy (ISS). Blood was collected to assess serum markers of peripheral TH action and peripheral blood mononuclear cells for TR mRNA determination by QRT-PCR. Growth parameters were also determined. Results: Although GH treatment didnot modify TR mRNA and serum markers of TH action in ISS as a whole group, the individual growth response to GH correlated positively with the change in TRα mRNA level and negatively with TRβ mRNA, TSH and SHBG. The change in each TR mRNA correlated negatively with their basal levels. Conclusions: GH therapy inducedindividual TR changes that correlated with growth velocity. Basal TR mRNA could predetermine the change in TR expression and therefore GH response.