The light microscopic investigation of the effects of in-ovo administered bisphenol A (BPA) on the development of testes

Abstract

The aim of this study was to determine the effects of BPA on testes development in chicken embryos. For this purpose, 310 fertile eggs of Isa Brown laying parent stock were divided into five groups as control, vehicle-control, 50, 100, and 250 µg/egg BPA. Test solutions were injected into the yolk before incubation. At the 13th, 18th and 21st days of incubation, the eggs were opened until six living male embryos were obtained from each group. Tissue samples were fixed in 10% buffered formalin (pH 7.4). After routine histological processes, tissue samples were embedded in paraffin. Six µm thickness sections were stained with the Crossmon’s trichrome method. All histological evaluation and histometrical measurements were performed on the left testes. On the 13th, 18th and 21st days of the incubation, the groups that were treated with BPA showed growth retardation in testicular tissues, fewer cell cords and poorly cellular organization. At 21 days of the incubation, there were a significant decrease in the mean diameter of the seminiferous tubule in all experimental groups compared to control groups (p<0.05). The increase in mean cortical thickness was observed in the BPA treated groups compared to the control groups (p<0.05). The mean testes surface area was higher at 50 µg/egg and 100µg/egg BPA treated groups compared to the control groups and at 250 µg/egg BPA administered group (p<0.05). In 50 and 100 µg/egg BPA treated chicken embryos, BPA triggered ovo-testis formation by characterizing thickened cortex containing oocytelike cell clusters whereas BPA had toxic effects at 250 μg/egg. It was concluded that BPA can induce both estrogen-like and toxic effects in the developing testes of chicken embryos in a dose-dependent manner

Keywords

• BPA
• chicken embryo
• testes

Yumurtaya verilen bisfenol A (BPA)' nın testislerin gelişimi üzerindeki etkilerinin ışık mikroskobikseviyede belirlenmesi

Abstract

amaçla Isa Brown ırkı yumurtacı tavuklara ait 310 adet döllü yumurta kontrol, taşıyıcı kontrol, 50, 100, 250 µg/yumurta BPA olmak üzere 5 gruba ayrıldı. Test solüsyonları inkübasyondan önce yumurta sarısına enjekte edildi. İnkübasyonun 13. 18. ve 21. günlerinde her gruptan 6 adet canlı erkek embriyo elde edilene kadar yumurtalar açıldı. Alınan testis dokuları %10'luk tamponlu formalin (pH 7.4) solüsyonunda tespit edildi. Dokular rutin histolojik metotlarla takip edilerek parafinde bloklandı. Bloklardan alınan 6 μm kalınlığındaki kesitlere ise Crossmon'un üçlü boyama yöntemi uygulandı. Tüm histolojik ve histometrik değerlendirmeler sol testis’ler üzerinde yapıldı. İnkübasyonun 13. 18. ve 21. günlerinde BPA uygulanan gruplarda testis dokularında gelişme geriliği, az sayıda hücre kordonu ve zayıf hücresel organizasyon gözlendi. İnkübasyonun 21. gününde deney gruplarının ortalama seminifer tubul çaplarında kontrol gruplarına kıyasla belirgin düşüşler tespit edildi (p<0.05). Kontrol gruplarına kıyasla deney gruplarında ortalama korteks kalınlığında artış gözlendi (p<0.05). Elli ve 100 µg/yumurta dozunda BPA uygulanan gruplar kontrol grupları ve 250 µg/yumurta dozunda BPA uygulanan grupla karşılaştırıldığında ortalama testis yüzey alanında önemli bir artış tespit edildi (p<0.05). Elli ve 100 µg/yumurta dozunda BPA uygulanan tavuk embriyolarında BPA'nın oosit benzeri hücre toplulukları içeren kalınlaşmış korteksle karakterize ovotestis gelişimini tetiklediği, buna karşın 250 µg/yumurta dozunda uygulanan BPA'nın ise toksik etkiye sahip olduğu görüldü. BPA'nın tavuk embriyolarında gelişmekte olan testisler üzerinde doza bağlı olarak hem toksik hem de östrojen benzeri etkilere neden olabileceği sonucuna varıldı

Keywords

• BPA
• tavuk embriyosu
• testis

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