Most regions of mouse epididymis are able to phagocytose immature germ cells

Abstract

The role of the epididymis as a quality control organ in preventing infertile gametes entering the ejaculate has been extensively explored, and it has been suggested that a specific region of mammalian epididymis is able to phagocytose abnormal germ cells. This study examines whether the epithelium of certain zones of the mouse epididymis can act as a selection barrier by removing immature germ cells from the lumen by phagocytosis. To detect the presence of immature germ cells in the epididymis, we generated transgenic mice expressing enhanced green fluorescent protein under the deleted in azoospermia-like (mDazl) promoter to easily identify immature germ cells under fluorescence microscopy. Using this technique, we observed that during the first stage of spermatogenesis in prepuberal mice, a wave of immature germ cells is released into the epididymis and that the immature epididymis is not able to react to this abnormal situation. By contrast, when immature germ cells were artificially released into the epididymis in adult mice, a phagocytic response was observed. Phagosomes appeared inside principal cells of the epididymal epithelium and were observed to contain immature germ cells at different degradation stages in different zones of the epididymis, following the main wave of immature germ cells. In this paper, we describe how the epididymal epithelium controls sperm quality by clearing immature germ cells in response to their artificially induced massive shedding into the epididymal lumen. Our observations indicate that this phenomenon is not restricted to a given epididymis region and that phagocytic capacity is gradually acquired during epididymal development.

Melatonin intake since weaning ameliorates steroidogenic function and sperm motility of streptozotocin‐induced diabetic rats

“…These data corroborated previous experimental (Amaral et al ., ; Scarano et al ., ) and clinical studies (Barták et al ., ; Padrón et al ., ; Niven et al ., ; La Vignera et al ., ) pointing impairments in sperm reserves and motility as a common reproductive damage in diabetes. Considering that the epididymis controls the quality of sperm integrity (Quintar et al ., ; Ramos‐Ibeas et al ., ), the decrease in sperm reserves without impairment of sperm production may reinforce that the quality of sperm was affected by diabetes. Thus, the altered cells must had been removed or degraded within the epididymis (Jones, ; Ramos‐Ibeas et al ., ).…”

“…Considering that the epididymis controls the quality of sperm integrity (Quintar et al ., ; Ramos‐Ibeas et al ., ), the decrease in sperm reserves without impairment of sperm production may reinforce that the quality of sperm was affected by diabetes. Thus, the altered cells must had been removed or degraded within the epididymis (Jones, ; Ramos‐Ibeas et al ., ). Numerous previous evidences demonstrate that diabetes alters sperm morphology and increases nuclear and mitochondrial DNA fragmentation (Barták et al ., ; Delfino et al ., ; Mallidis et al ., ).…”

Exposure to the widely used herbicide atrazine results in deregulation of global tissue-specific RNA transcription in the third generation and is associated with a global decrease of histone trimethylation in mice

“…The SG derived from affected cells have modified transcriptional network that impacts both meiotic and post-meiotic testis fractions. The defective meiotic and post-meiotic cells could be eliminated either by Sertoli cell phagocytosis (116) or in epididymis, as mouse epididymis is able to phagocyte immature germ cells (117) and ultimately lead to spermatozoa decrease. Besides that, transcriptional factors expressed in the epididymis control the chromatin assembly on the genome-wide level and could contribute to transmission of altered information to subsequent progeny.…”

Successful ICSI in Mice Using Caput Epididymal Spermatozoa

“…In these assays, sperm retrieved from the distal part acquire a higher motility and ability to fertilize the oocyte (Sullivan and Mieusset, 2016). The epididymis is also able to eliminate defective or immature germ cells (Ramos-Ibeas et al, 2013).…”