Riosiguat'ın Soğukta Saklanan Koç Spermasında Motilite, Membran Fonksiyonu ve DNA Bütünlüğü Üzerindeki Etkileri

Öz

Bu çalışmada, koç spermasının 5°C’de kısa süreli saklanması sırasında sulandırıcıya eklenen riosiguatın sperm fonksiyonları üzerindeki etkileri araştırılmıştır. Çalışmada üreme mevsiminde sekiz sağlıklı Tuj koçundan elde edilen ejakülatlar pooling yapılıp, 400×10⁶ sperm/mL yoğunluğa ayarlanarak beş eşit gruba ayrılmıştır. Deney grupları; kontrol (0 µM), 0.5 µM, 5 µM, 50 µM ve 250 µM riosiguat içerecek şekilde hazırlanmış ve örnekler 5 °C’de 72 saat süreyle saklanmıştır. Spermatolojik değerlendirmeler 0. ve 72. saatlerde total motilite, canlılık, plazma membran bütünlüğü, anormal spermatozoon oranı ve DNA bütünlüğü açısından gerçekleştirilmiştir. Elde edilen bulgular, riosiguatın sperm fonksiyonları üzerinde doza bağlı bifazik etki gösterdiğini ortaya koymuştur. Özellikle 0.5 ve 5 µM riosiguat içeren gruplarda 72. saatte total motilite ve canlılık oranlarının daha iyi korunduğu, plazma membran bütünlüğünün ise kontrol grubuna kıyasla anlamlı düzeyde yüksek olduğu belirlenmiştir (P<0.05). Ayrıca, 72. saatte DNA bütünlüğü, kontrol grubuna kıyasla riociguat ile tedavi edilen tüm gruplarda önemli ölçüde daha yüksekti (P<0.05). Buna karşın, yüksek doz riosiguat (250 µM) uygulamasında spermatozoona ait baş ve kuyruk anomalilerinin arttığı gözlenmiştir. Sonuç olarak, riosiguatın düşük dozlarda (özellikle 0.5 ve 5 µM) koç spermasının kısa süreli soğukta saklanması sırasında motilite, membran fonksiyonu ve DNA bütünlüğünü koruyucu etki gösterdiği; ancak yüksek dozlarda morfolojik bozukluk riskini artırabileceği belirlenmiştir. Bu bulgular, riosiguatın uygun dozlarda kullanıldığında sperm sulandırıcılarına potansiyel bir katkı maddesi olabileceğini göstermektedir.

Anahtar Kelimeler

• DNA
• koç
• riosiguat
• sperma

Etik Beyan

Çalışmamızda etik kurallara uyulmuş olup Atatürk Üniversitesi Hayvan Deneyleri Yerel Etik Kurulu Başkanlığından 2025/04 sayılı etik kurulu raporu mevcuttur.

Effects of Riociguat on Sperm Motility, Membrane Function and DNA Integrity in Chilled Stored Ram Sperm

Öz

This study aimed to investigate the effects of riociguat supplementation in semen extender on sperm functional parameters during short-term storage of ram semen at 5°C. Semen samples were collected from eight healthy, sexually mature Tuj rams during the breeding season, pooled, and diluted to a final concentration of 400×10⁶ sperm/mL. The samples were divided into five equal groups: control (0 µM), 0.5 µM, 5 µM, 50 µM and 250 µM riociguat. All groups were stored at 5 °C for 72 hours, and sperm evaluations were performed at 0 and 72 hours. Spermatological assessments included total motility, viability, plasma membrane integrity, abnormal spermatozoa rates, and DNA integrity. The results demonstrated that riociguat exerted a dose-dependent biphasic effect on sperm quality. At 72 hours, sperm samples supplemented with 0.5 and 5 µM riociguat showed significantly higher total motility and viability compared to the control group (P<0.05). Plasma membrane integrity was also better preserved in these low-dose groups, with the highest values observed in the 5 µM riociguat group. Moreover, DNA integrity at 72 hours was significantly higher in all riociguat-treated groups compared to the control (P<0.05). Conversely, high-dose riociguat supplementation (250 µM) resulted in an increased incidence of sperm head and tail abnormalities, indicating potential detrimental effects at excessive concentrations. These findings suggest that while physiological activation of the NO–sGC–cGMP pathway by low-dose riociguat supports mitochondrial function and cellular homeostasis, excessive stimulation may disrupt sperm morphology and function. In conclusion, low-dose riociguat supplementation, particularly at 0.5 and 5 µM, effectively preserves motility, membrane integrity, and DNA integrity of ram sperm during short-term chilled storage. However, higher doses may negatively affect sperm morphology. Riociguat may represent a novel additive for semen extenders, provided that optimal dose ranges are carefully determined.

Anahtar Kelimeler

• DNA
• ram
• riociguat
• semen

Etik Beyan

Our study complies with ethical guidelines, and an ethics committee report numbered 2025/04 from the Atatürk University Animal Experiments Local Ethics Committee is available.

Kaynakça

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