CANSU AKBULUT, Çağhan KIZIL, Nazan Deniz YÖN

Effects of low doses of bisphenol A on primordial germ cells in zebrafish (Danio rerio) embryos and larvae

Primordiyal germ hücreleri, eşeyli üreyen canlılarda gametlerin öncül hücreleridir. Endokrin sistem hormonları ve çevresel etkenler, primordiyal germ hücrelerinin göçünü etkilemektedir. İnsanların maruz kaldığı çevresel kirleticilerden biri de bisfenol A (BPA)dır. Endokrin sistemde hasar oluşturan biri olan BPA, genellikle plastik sertleştirme işleminde kullanılmaktadır. Bu çalışmada zebra balığı embriyo ve larvalarında düşük dozlardaki (4 mg/L and 8 mg/L) BPAnın etkileri incelenmiştir. Bir germ hücresi belirteci gen olan vasa ile yapılan whole mount in situ hibridizasyon deneyleri sonucunda BPAnın primordiyal germ hücre sayısında artışa sebep olduğu ve bu hücrelerin göç yolu dışındaki (ektopik) bölgelerde bulunduğu tespit edilmiştir. Primordiyal germ hücrelerinin ektopik bölgelere göçü ve bu hücrelerdeki morfolojik değişiklikler histolojik çalışmalarla da doğrulanmıştır. Buna ek olarak, düşük dozlarıyla yapılan boyamalarda apoptozisin tespitinde kullanılan akridin turuncusu boyaması sonucunda BPAnın apoptozisi artırmadığı saptanmıştır. Bu çalışma sonuçları, düşük dozlardaki BPAnın primordiyal germ hücre sayısını artırdığını ve bu hücrelerin ektopik bölgelere göç etmesine yol açtığını ortaya koymaktadır.

Düşük dozlardaki bisfenol Anın zebra balığı (Danio rerio) embriyo ve larvalarında primordiyal germ hücreleri üzerine etkisi

Primordial germ cells are the precursors of gametes in sexually reproducing organisms. The migration and homing process of primordial germ cells are prone to environmental effects and the endocrine system hormones. One of the environmental pollutants which humans are exposed to is bisfenol A (BPA). BPA which is an endocrine disrupter generally used for making plastics harder. In this study we investigated the effects of low doses of BPA (4 mg/L and 8 mg/L) on primordial germ cells at the zebrafish embryos and larvae. Whole mount in situ hybridization for germ cell marker gene vasa showed that upon exposure to BPA, the primordial germ cell number increased and these cells ectopically localized outside the normal germ cell niche in zebrafish. Migration of primordial germ cells into ectopic locations and morphological changes in these cells were also proved by histological studies. Additionally, results of acridine orange staining to detect apoptotic cells showed that low doses of BPA did not increase apoptosis. Results of the present study showed that low doses of BPA exposure increased the number of primordial germ cells and induced ectopic primordial germ cell localization in the zebrafish embryos.

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