Aktuğ H., B. KOSOVA, Yavaşoğlu A, V. B. ÇETİNTAŞ

Evaluation of caspase-3 and bcl-2 expressions in spleen tissue of streptozotocin-induced diabetic rats by immunohistochemistry and quantitative RT-PCR

Amaç : Dalak dokusu iki fonksiyonel ve farklı yapıdan bir araya gelmektedir, kırmızı pulpa ve beyaz pulpa. Bu çalışmanın amacı streptozotocin ile indüklenmiş diyabetik sıçanlarda dalak dokusundaki aktive olan apoptotik yolakları araştırmaktı. Oluşturulan hayvan modelinde diyabetin apoptotik etkileri her iki yapıda araştırıldı. Gereç ve Yöntem : Çalışma grupları sağlıklı kontrollerden (Grup 1, n = 10) ve streptozotocin ile indüklenmiş diyabetik sıçanlardan (Grup 2, n = 10) oluşmaktaydı. Hücre morfolojisi ve bütünlüğü ışık mikroskobu altında hematoksilen ile eozin boyası ile değerlendirildi. Apoptoz, Caspaz-3 ve Bcl-2' nin immunohistokimyasal ve gerçek-zamanlı kantitatif polimeraz zincir reaksiyon (RT-PCR) analizleriyle belirlendi. Bulgular: Tüm sonuçlar istatistiksel olarak değerlendirildi. Çalışmamızın sonucunda diyabetik grupta fibrotik alanın daralarak, dalak kontüründe bir bozukluk meydana getirdiği ve parankimal dokunun yaygın olarak genişleyerek beyaz pulpanın marjinal zonunu ve foliküler alanını kapsadığı gözlendi. Diyabetik grup immunohistokimyasal olarak analiz edildiğinde ayrıca daha fazla hücrenin Caspaz-3'ü arttırarak ve Bcl-2 ekspresyonunu baskılayarak apoptotik süreci aktive ettiği izlendi. Bununla uyumlu şekilde diyabetik gruptaki Caspaz-3 mRNA ekspresyonu kontrol grubuna göre artmış, Bcl-2 mRNA ekspresyonu ise anlamlı şekilde azalmış oldukları bulundu. Sonuç: Bu bulgular diyabetin dalakta Caspaz-3 ve Bcl-2 üzerinden apoptotik yolaklar üzerinde önemli etkileri bulunduğunu düşündürmektedir.

Streptozotosine bağlı diabetik ratların dalak dokusunda caspase-3 ve bcl-2 ekspresyonlarının immünohistokimyasal ve kantitatif RT-PCR ile değerlendirilmesi

Aim : Spleen tissue is comprised of two functionally and morphologically distinct components, the red pulp and the white pulp. Aim of this study to evaluate the activated apoptotic pathways in spleen tissue of streptozotocin-induced diabetic rats. Apoptotic effects of diabetes in the generated animal model were analyzed in both components. Material and Methods: The working groups consisted of healthy controls (Group 1, n = 10) and streptozotocin-induced diabetic rats (Group 2, n = 10). Cell morphology and integrity was evaluated by light microscopy using hematoxylin and eosin staining. Apoptosis was determined by immunohistochemical and real-time quantitative polymerase chain reaction (RT-PCR) analysis of Caspase- 3 and Bcl-2. Results: All results were evaluated statistically. At the end of our study we determined that in the diabetic group fibrotic area contracted, causing distortion of the splenic contour and that the paranchymal fibrosis was sufficiently extensive to involve the marginal zone and follicular areas of the white pulp. In the diabetic group also more cells activated the process of apoptosis by increasing Caspase-3 and suppressing Bcl-2 expression when analyzed immunohistochemically. In agreement mRNA expression of Caspase-3 was higher in the diabetic group compared to that of the control group, whereas mRNA expression of Bcl-2 was significantly lower determined. Conclusion: These findings suggest that in spleen diabetes has an important influence on apoptotic pathways through Caspase-3 and Bcl-2.

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