The formation of mature spermatozoa is one of the most essential functions in life. A concerted sequence of events is needed to proliferate, maintain and mature germ cells starting with spermatogonial stem cells and culminating in mature gametes. Apart from the genetic background, this process requires highly organized tissue in which the complex process of spermatogenesis is strongly regulated...

The past several decades witnessed great advances in the Andrology Sciences in humans. This certainly increased our knowledge in understanding the process of spermatogenesis, capacitation, and fertilization. Much of this work has been acquired from animal experimentation (1, 2, 3). However, the introduction of assisted reproductive technology improved our understanding of the process of fertili...

Spermatogenesis is a strictly regulated process, at both the transcriptional and the posttranscriptional level, which allows continuous gamete production throughout adulthood. A novel mechanism of posttranscriptional control mediated by microRNAs (miRNAs) has lately emerged as an important regulator of spermatogenesis. miRNAs are endogenous, small, noncoding RNAs produced through a multistep en...

Steroidogenesis plays a key role in the development and maintenance of male reproductive function and fertility. The objective of the present study was to investigate the effect of Carica papaya seed extract on steroidogenesis. The reduced cholesterol levels indicate decreased mobilization towards androgenesis which leads to decreased steroidogenesis and thereby inhibition of spermatogenesis in...

The generation of functional sperm in vitro has been a goal for almost a century. Until recently, researchers have only succeeded in reproducing the early steps of spermatogenesis. This is not surprising given that spermatogenesis is a complicated process that requires the coordinated efforts of germ cells and several somatic cells within the tubular structure of the testis. Finally-last year-S...

INTRODUCTION Genes involved in testicular differentiation, spermatogenesis, proliferation and apoptosis of germ cells have been shown to evolve rapidly and display rapid DNA changes. These genes are therefore good candidates for explaining impairments in spermatogenesis. Initial studies of some of these genes appear to confirm this hypothesis. The RHOXF2 candidate gene belongs to the RHOX famil...

OBJECTIVE It is generally accepted that both gonadotropins LH and FSH are necessary for initiation and maintenance of spermatogenesis. We investigated the relative importance of FSH for the maintenance of spermatogenesis in hypogonadotropic men. SUBJECTS AND METHODS 13 patients with gonadotropin deficiency due to idiopathic hypogonadotropic hypogonadism (IHH), Kallmann syndrome or pituitary i...

Ztbt20 is a POK family transcription factor and primarily functions through its conserved C2H2 Krüppel type zinc finger and BTB/POZ domains. The present study was designed to define the function of the Zbtb20, in vivo, during mouse spermatogenesis. Immunohistochemical studies revealed that ZBTB20 protein was localized specifically in the nuclei of Sertoli cells in seminiferous tubules. To inves...

Studies using genetics and vitamin A deficiency (VAD) have shown that vitamin A and retinoids play essential roles in spermatogenesis at the pre-meiotic stage. To understand the mechanisms of control in spermatogenesis by retinoic acid, we investigated whether retinoic acids regulate the expression of downstream transcription factors that are essential for spermatogenesis. In this study, we fou...

In a previous study we identified active Notch signaling in key cellular events occurring at adult spermatogenesis. In this study, we evaluated the function of Notch signaling in spermatogenesis through the effects of in vivo Notch blockade. Adult CD1 male mice were either submitted to a long term DAPT (?-secretase inhibitor) or vehicle treatment. Treatment duration was designed to attain one h...