Farklı selenyum seviyelerinin tiroid hormon sentezi üzerine etkisi

Abstract

Amaç: Selenyum esansiyel bir element olup tiroid fonksiyonları açısından oldukça önemlidir. Periferde tiroksin’den triiyodotironin üretiminden sorumlu olan iyodotironin deiyodinaz-I selenyum içeren bir enzimdir. Bu çalışmanın amacı, farklı selenyum düzeylerinin tiroid hormon sentezi üzerine etkisinin araştırılmasıdır. Yöntemler: 2012-2014 yılları arasında Ankara Meslek Hastalıkları Hastanesinin çeşitli polikliniklerine başvuran tiroid hormonları ve serum selenyum düzeylerine bakılan 303 kişi serum selenyum seviyelerine göre 3 gruba ayrıldı. Grup 1: 50-75 μg/L, grup 2: 75,1-100 μg/L, grup 3: 100,1-125 μg/L. Grupların tiroid stimüle edici hormon TSH , serbest T3 FT3 serbest T4 FT4 düzeyleri birbirleriyle karşılaştırıldı. Bulgular: Serum TSH ve FT3 düzeyleri açısından 3 grup arasında istatistiksel olarak anlamlı bir fark yoktu p=0,91; p=0,18 . Serum FT4 düzeyleri grup 3’te diğer gruplara göre düşüktü. Bu fark grup 1 ve 3 arasında istatiksel olarak anlamlı idi p=0,005 . T3/T4 oranı grup 3’te diğer gruplardan anlamlı olarak yüksekti p=0,004 . Selenyum ile FT4 düzeyleri arasında negatif bir korelasyon r=-0,184; p=0,001 varken selenyum ile T3/T4 oranlarıları arasında pozitif korelasyon r=0,178, p=0,002 vardı. Sonuç: Selenyum; tiroid fonksiyonlarında önemli bir rol üstlenmekte olup selenyum eksikliğinde FT4 düzeyi artmaktadır. FT4 yüksekliğinde serum selenyum düzeyinin düşük olabileceği akılda tutulmalıdır.

Keywords

• İyodotironin deiyodinaz I, selenyum, tiroid hormonları

Effect of different selenium levels on thyroid hormone synthesis

Abstract

Objective: As an essential element, selenium is very important for thyroid functions. Iodothyronine deiodinase-I is a selenium containing enzyme that is responsible for production of triiodothyronine T3 from thyroxin T4 in peripheral tissues. The aim of this study is to investigate the effect of different levels of selenium on thyroid hormone synthesis. Methods: 303 participants who had admitted to several clinics of Ankara Occupational Diseases Hospital and whose serum thyroid hormone and selenium levels were determined between years 2012 and 2014 were separated into 3 groups according to serum selenium levels. Group 1: 50-75 µg/L, group 2: 75,1-100 µg/L, group 3: 100,1-125 µg/L. The thyroid stimulating hormone TSH , free T3 FT3 and free T4 FT4 levels of groups were compared with each other. Results: There was statistically non-significant difference among 3 groups concerning the serum TSH and FT3 levels p=0,91; p=0,18 . Group 3 serum FT4 levels were lower than other groups. FT4 levels of group 3 were significantly different from group 1 p= 0,005 . T3/T4 ratio was significantly higher in group 3 than other groups p=0,004 . There was a negative correlation between selenium and FT4 levels r=-0,184; p=0,001 , whereas a positive correlation existed between selenium and T3/T4 ratio r=0,178, p=0,002 . Conclusion: Selenium has an important role in thyroid functions and FT4 levels increase in selenium deficiency. High FT4 levels should be considered in low selenium levels

Keywords

• Iodothyronine deiodinase I, selenium, thyroid hormones

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