Ercan BABUR, Umut BAKKALOĞLU, Cem SÜER, Nurcan DURSUN

Tiroid Hormon İlişkili Deiyodinaz Enzim Seviyelerindeki Değişikliklere Selenyumun Etkisi

Amaç: Bu çalışmanın amacı selenyumun tiroid hormon ilişkili deiodinaz enzim seviyeleri üzerine etkisini araştırmaktır. Araçlar ve Yöntem: Deneyler 2 aylık, yetişkin, erkek Wistar Albino sıçanlar üzerinde gerçekleştirilmiştir. Çalışmada toplam 32 adet sıçan kullanılmıştır. Kontrol grubu (Kontrol, n=8, serum fizyolojik uygulanmıştır), hipotiroid (6-n-propil tiyourasil (Ptu), n=8, 1mg/kg/gün Ptu, hipotiroid+sodyum selenit (Sena, n=8, Ptu+0.5mg/kg/gün sodyum selenit) ve hipotiroid+seleno-L-metiyonin (Semet, n=8, Ptu+0.7mg/kg/gün seleno-L-metiyonin) grubu olmak üzere 4 grup oluşturulmuştur. Tüm maddeler 21 gün boyunca gastrik gavaj tekniği ile uygulanmıştır. Deney sonrası sakrifiye edilen sıçanlardan heparinli tüp içine alınan kan örnekleri 4000 rpm’ de 5 dakika süre ile santrifüj edilerek plazmaları ayrılmıştır. Dekapite edilen sıçanların hipokampüsleri çıkarılmıştır. Hipokampüs deiyodinaz 2 (DİO2) ve deiyodinaz 3 (DİO3) protein seviyeleri western blot yöntemi ile ölçülmüştür. Plazma ve beyin selenyum değerleri, kütle spektrometre yöntemi ile ölçülmüştür. Plazma serbest Triiyodotironin (T3) ve Tiroksin (T4) seviyeleri ticari ELISA kiti kullanılarak ölçülmüştür. Bulgular: Hipokampüs DİO2 enzim seviyeleri Ptu grubunda kontrol grubuna göre artmış (p=0.04), DİO3 ise azalmıştır (p=0.001). Selenyum takviyeli gruplarda ise hipotiroidide gelişen bu farklılık ortadan kalkmıştır. Sonuç: Bu bulgular hipotiroidi hastalarında selenyum takviyesinin tiroid hormon seviyesindeki bozuklukları iyileştirebileceğini düşündürmektedir.

Anahtar Kelimeler:

Deiyodinaz, Hipokampüs, Tiroid Hormonları, Selenyum

The Effect of Selenium on Changes in Thyroid Hormone-Related Deiodinase Enzyme Levels

Purpose: The aim of this study is to investigate the effect of selenium on thyroid hormone-related deiodinase enzyme levels. Materials and Methods: The experiments were carried out on adult male Wistar rats aged 2 months. In total, 32 rats were used in the study. The rats were divided into 4 groups; control (Control, n=8, saline was applied), hypothyroid (6-n-propyl thiouracil (Ptu), n=8, 1mg/kg/day Ptu), hypothyroid+sodium selenite (Sena, n=8, Ptu+0.5mg/kg/day sodium selenite) and hypothyroid+seleno-L- methionine (Semet, n=8, Ptu+0.7mg/kg/day seleno-L-methionine) group. All drugs were administered with gastric gavage technique for 21 days. After the experiment, the blood samples taken from the rats sacrificed in a heparin tube were centrifuged at 4000 rpm for 5 minutes and their plasmas were separated. The hippocampus of the decapitated rats was removed. Hippocampus (deiodinase 2) DIO2 and (deiodinase 3) DIO3 protein levels were measured with western blot method. Se values on plasma and hippocampus were measured with inductively coupled plasma-mass spectrometry. Plasma-free Triiodothyronine (T3) and thyroxine (T4) levels were measured using a commercial ELISA kit. Results: Hippocampus DIO2 enzyme levels increased in the Ptu group compared to the control group (p=0.04) and DIO3 decreased (p=0.001). In the selenium (Se) supplemented groups, this difference in hypothyroidism disappeared. Conclusion: These findings suggest that selenium supplementation may improve thyroid hormone levels in patients with hypothyroidism.

Keywords:

Deiodinase, Hippocampus, Thyroid Hormone, Selenium,

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