Energy metabolism disorders of sertoli cells in azoospermia etiology

Abstract

Objective: Based on the hypothesis, there may be difference in synthesis of lactose which is the main energy source used by spermatozoa in Sertoli cells between nonobstructive azoospermia NOA and obstructive azoospermia OA males, we aimed to analyze PKM1, PKM2 and LDHB gene expression levels and mitochondria numbers in the patient and control groups’ Sertoli cells comparatively. Material and Methods: In this study, Sertoli cells were isolated from NOA and OA patients’ testis tissues. PKM1, PKM2 and LDHB genes expression levels were measured by RT-PCR. Mitochondria were stained by Mitotracker red. Stained mitochondria percentage were determined by flow cytometry analysis. Results: PKM1, PKM2, LDHB genes expression levels were observed 198,01-, 162,01-, 50.79- fold lower in NOA group than OA group, respectively. According to the results of mitotracker stained test, 34,6% mitochondria were stained in NOA group, 52,4% mitochondria were stained in OA group. Conclusion: Despite the reduction in the mitochondria numbers of our patients, significant decrease in gene expression levels of the enzyme in the glycolytic pathway compared to the control was observed. This result showed that there was metabolic dysfunction in the development of sperm cells, thus playing an important role in infertility

Keywords

• Sertoli cells,energy metabolism,male infertility,azoospermia

Azoospermi etyolojisinde sertoli hücresi enerji metabolizması bozuklukları

Abstract

Amaç: Nonobstrüktif NOA ve obstrüktif OA azoospermili bireylerin Sertoli hücrelerinde spermatozoanın başlıca kullandığı enerji kaynağı olan laktatın sentezlenmesinde farklılık olabileceği hipotezinden yola çıkarak, PKM1, PKM2 ve LDHB enzimlerinin ifadelerinin, mitokondri sayısının hasta ve kontrol grubunun Sertoli hücrelerinde karşılaştırmalı olarak belirlenmesi ve metabolizmanın fertilite üzerine olası etkilerinin araştırılması amaçlandı. Gereç ve Yöntem: Bu çalışmada NOA ve OA’lı bireylerin testis dokularından Sertoli hücreleri izole edildi. Sertoli hücrelerinde enerji metabolizmasında görevli PKM1,PKM2 ve LDHB genlerinin ifadesi RT-PCR analizi ile ölçüldü. OA ve NOA’lı Sertoli hücrelerinde mitokondri boyaması Mitotraker Red ile gerçekleştirildi. Boyanan Mitokondri yüzdeleri flow sitometi analizi ile tespit edildi. Bulgular: Real Time PCR analiz sonuçlarına göre PKM1, PKM2, LDHB gen ifadeleri OA’lı gruba göre sırasıyla 198,01-, 162,01-, 50.79- kat düşük olduğu hesaplandı. Mitotraker boyama sonuçlarına göre OA’lı bireylerin Sertoli hücreleri NOA’lı bireylerin Sertoli hücreleri ile karşılaştırıldığında, NOA’lı grupta %34,6 boyanma mevcutken OA’lı grupta %52,4 boyanma tespit edildi. Sonuç: Hastalarımızın mitokondri sayısında azalma olmasına rağmen glikolitik yolak enzimlerinde de kontrole göre önemli bir azalma saptanması, Sertoli hücrelerindeki metabolik disfonksiyonun sperm hücre gelişiminde, dolayısıyla infertilitede önemli rolü olduğunu desteklemektedir.

Keywords

• Sertoli hücresi,enerji metabolizması,erkek infertilitesi,azoospermi

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