Adult Male Syrian Hamsters (Mesocricetus auratus) Exhibit Daily Oscillations in Their Serum Levels of Melatonin and Leptin As Well As in the Expression of the GnRH, GnIH, and Kisspeptin Genes

Yıl 2023, Cilt: 10 Sayı: 1, 68 - 75, 28.01.2023

Emine İnci Balkan , Bülent Gündüz

https://doi.org/10.30910/turkjans.1196793

Öz

The complex neuronal and hormonal interaction between the brain and gonads controls the neuroendocrine reproductive axis. GnRH, GnIH, and kisspeptin are important neuropeptides in this relationship. Although seasonal variations of these neuropeptides have been demonstrated in photoperiodic animals, there is no clear evidence in their daily rhythms. Melatonin and leptin hormones are also two important hormones in reproductive regulation. In our study, the relationship of melatonin and leptin hormones with daily rhythm with GnIH, GnRH, and kisspeptin gene expressions and protein oscillations was examined. Adult male Syrian hamsters were exposed to the long photoperiod and at the end of the 30-day experimental period, blood and tissue samples from each group were collected at 04:00 h, 12:00 h, 20:00 h, and 00:00 h. Daily rhythms of melatonin and leptin hormones were determined by ELISA. Quantitative analysis of GnRH, GnIH, Kisspeptin, and β-actin genes was performed with the corresponding primers in Real-Time PCR. Protein expressions were determined by the Western Blot technique. Serum melatonin and leptin levels showed an inverse rhythmic relationship. Leptin level was found to be low while melatonin was high in the dark. Daily rhythms were observed in GnIH, GnRH, and kisspeptin mRNA expressions and protein oscillations. As a result, our findings could imply that all of the relationships between melatonin, leptin, GnIH, GnRH, and kisspeptin are not reproductive, but rather metabolic in nature.

Anahtar Kelimeler

Gene expression, GnIH, GnRH, Kisspeptin, Leptin, Melatonin

Destekleyen Kurum

Canakkale Onsekiz Mart Üniversity

Proje Numarası

FDK-2021-3831

Teşekkür

This study was funded by the Scientific Research Projects Coordination Unit at Çanakkale Onsekiz Mart University (FDK-2021-3831)

Yetişkin Erkek Suriye Hamsterleri (Mesocricetus auratus), Serum Melatonin ve Leptin Seviyelerinde ve Ayrıca GnRH, GnIH ve Kisspeptin Genlerinin Ekspresyonunda Günlük Ritim Gösterir

Öz

Nöroendokrin ve üreme sistemi beyin ve gonadlar arasındaki kompleks nöronal ve hormonal etkileşim ile kontrol edilmektedir. GnRH, GnIH ve Kisspeptin bu ilişkide önemli nöropeptidlerdir. Bu nöropeptitlerin mevsimsel olarak değişimleri fotoperiyodik hayvanlarda gösterilmiş olsa da, günlük ritimlerinde net bir bilgi bulunmamaktadır. Ayrıca, melatonin ve leptin hormonları da üremenin düzenlenmesinde önemli iki hormondur. Çalışmamızda günlük melatonin ve leptin ritimlerinin GnIH, GnRH ve kisspeptin gen ekspresyonları ve protein salınımları ile ilişkisi incelendi. Yetişkin erkek Suriye hamsterleri uzun fotoperiyotta tutuldular. 30 günlük deney süresinin sonunda her gruptan günün 04:00, 12:00, 20:00 ve 00:00 saatlerinde kan ve doku örnekleri alındı. Melatonin ve leptin hormonlarının günlük ritimleri ELISA ile belirlendi. Real Time PCR yöntemiyle GnRH, GnIH, kisspeptin ve β-aktin genlerine karşılık gelen primerler kullanılarak bu genlerin kantitatif analizi yapıldı. Protein ifadeleri Western Blot tekniği ile belirlendi. Serum melatonin ve leptin seviyeleri ters yönlü ritmik ilişki gösterdi. Karanlıkta leptin düzeyi düşük, melatonin düzeyi yüksek bulundu. GnIH, GnRH ve Kisspeptin mRNA ifadelerinde ve protein salınımlarında günlük ritimler gözlendi. Sonuç olarak bulgularımız, melatonin, leptin, GnIH, GnRH ve kisspeptin arasındaki ilişkilerin üreme üzerinde olmayabileceği ancak metabolik olabileceğini düşündürmektedir

Anahtar Kelimeler

Gen ekspresyonu, GnIH, GnRH, Kisspeptin, Leptin, Melatonin

Proje Numarası

FDK-2021-3831

Kaynakça

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