Dexamethasonun 18 Günlük Embriyonik Civciv Bağırsağındaki Claudin Sıkı Bağlantı Proteinlerine Etkileri

Abstract

Claudin (cldn) protein ailesi sıkı bağlantı yapılarının (tight junctions) temel birleşenidir ve sıkı bağlantı zincirlerinin

bariyer fonksiyonuna direk etki eder. Sıkı bağlantıların gelişmiş dokulardaki bariyer fonksiyonuna katkısının yanında, bu

bağlantı proteinleri, epitelin embriyonik gelişimi süresince mevcuttur ve normal gelişim için gereklidir. Glukokortikoitler

bağırsak dahil birçok dokunun embriyonik gelişimi için esastır. Aynı şekilde, sıkı bağlantıların bütünleşmesine uyarıcı

etkileri mevcuttur. Bu çalışmada, sentetik bir glukokortikoit olan dexamethasone (DEX)’in in vitro koşullarda 18 günlük

embriyonik civciv bağırsağındaki sıkı bağlantı proteinlerinin mRNA ekspresyonlarına bir etkisinin olup olmadığı kantitatif

Real-Time PCR (RT-PCR) kullanılarak araştırıldı. Henüz yumurtadan çıkmamış civciv bağırsağı bu çalışma için

uygun bir model olmaktadır, çünkü epitelyumdaki bariyer henüz tam olarak oluşmamış ve ayrıca bu bağırsak 24 saatlik

organ kültüründe morfolojik bütünlüğünü koruyabilmektedir. RT-PCR analizleri hem cldn-3 hem de cldn-5 sıkı bağlantı

proteinlerinin gen ekspresyonlarının DEX’in etkisiyle doza bağlı olarak arttığını ortaya çıkartmıştır.

Keywords

• Bağırsak,claudin,dexamethasone,gen ekspresyonu,glukokortikoidler

The Effects of Dexamethasone on Claudin Tight Junction proteins in 18-day Embryonic Chick Intestine

Abstract

Claudin (cldn) protein family is the main component of tight junction (TJ) strands and it is directly involved in the barrier function of TJs. In addition to the contributing to the barrier function of TJs in mature tissues, these junctions are also present and required for normal embryonic development of epithelial sheets. Glucocorticoids (GC) are essential for the maturation of numerous tissues including the intestine during embryonic development. They also have stimulatory effects on the integrity of tight junctions. In this study, the effect of a synthetic glucocorticoid, dexamethasone (DEX) on mRNA expression of tight junctional proteins was investigated in 18-day embryonic chick intestine in vitro using quantitative Real-Time PCR (RT-PCR) analyses. Pre-hatched chick intestine will provide a convenient model because the organization of the barrier is not completely established, and it is relatively easy to maintain its morphological integrity for at least 24 hours in an organ culture system. RT-PCR analyses revealed that both claudin-3 (cldn-3) and claudin-5 (cldn-5) tight junction gene expressions were induced in response to DEX in a dose dependent manner. 

Keywords

• Claudin,dexamethasone,gene expression,glucocorticoids,intestine

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