Abstract
The role of circRNA in reproduction is under investigation. CircRNAs are expressed in human testis, spermatozoa (SPZ), and seminal plasma. Their involvement in embryo development has also been suggested. Asthenozoospermia, a common cause of male infertility, is characterized by reduced or absent sperm motility in fresh ejaculate. While abnormal mitochondrial function, altered sperm tail, and genomic causes have been deeply investigated, the epigenetic signature of asthenozoospermic derived SPZ still remains unexplored. CircRNAs may take part in the repertoire of differentially expressed molecules in infertile men. Considering this background, we carried out a circRNA microarray, identifying a total of 9,138 transcripts, 22% of them novel based and 83.5% with an exonic structure. Using KEGG analysis, we evaluated the circRNA contribution in pathways related to mitochondrial function and sperm motility. In order to discriminate circRNAs with a differential expression in SPZ with differential morphological parameters, we separated sperm cells by Percoll gradient and analyzed their differential circRNA payload. A bioinformatic approach was then utilized to build a circRNA/miRNA/mRNA network. With the aim to demonstrate a dynamic contribution of circRNAs to the sperm epigenetic signature, we verified their modulation as a consequence of an oral amino acid supplementation, efficacious in improving SPZ motility.
Highlights
Spermiogenesis is the differentiation phase at the end of spermatogenesis that allows the transformation of round spermatids into spematozoa (SPZ), highly specialized cells provided with a head containing an elongated and transcriptionally inactive nucleus, an acrosome, and a tail, surrounded by a mitochondrial sheet at its midpiece [1, 2]
Abnormal morphology, and poor sperm motility are common causes of male infertility: according to the reports released by the World Health Organization [4], asthenozoospermia is defined as the total motility
Thinking at circular RNA (circRNA) as potential biomarkers of sperm quality, beyond classical morphological parameters, we evaluated their modulation in SPZ of asthenozoospermic patients before and after pharmacological treatments aimed at improving their clinical profile
Summary
Spermiogenesis is the differentiation phase at the end of spermatogenesis that allows the transformation of round spermatids into spematozoa (SPZ), highly specialized cells provided with a head containing an elongated and transcriptionally inactive nucleus, an acrosome, and a tail, surrounded by a mitochondrial sheet at its midpiece [1, 2] Such a morphology is acquired through impressive remodeling events consisting of: (i) acrosome formation starting from Golgi-derived vesicles; (ii) histone replacement with protamines in order to obtain a tightly packaged chromatin; and (iii) global reorganization of the cytoskeleton architecture necessary for flagellum development [3]. The mRNA fingerprint has been drawn in fertile men [9] as well as in asthenozoospermic patients [10] This strategy has been deeply applied to unveil several other classes of non-coding RNAs [11]. Studies that focus on the identification of differentially expressed RNAs in infertile patients, when compared to fertile controls, may shed light on the pathogenic mechanisms involved in asthenozoospermia
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
