Sperm mRNAs as potential markers of male fertility.

Advances in transcriptomic technologies are contributing to an increased understanding of the role of spermatozoal RNA in sperm physiology. Although sperm transcriptomic studies have delivered large amounts of valuable information, no new male fertility biomarkers have emerged from such studies to date. This review summarizes current knowledge about the potential relevance of certain mRNA as biomarkers, focusing on comparative studies of human spermatozoa transcriptomic profiles from fertile and pathological semen samples.

Gene transcription profiling of astheno- and normo-zoospermic sperm subpopulations.

Spermatozoa contain a repertoire of RNAs considered to be potential functional fertility biomarkers. In this study, the gene expression of human sperm subpopulations with high (F1) and low (F2) motility from healthy normozoospermic (N) and asthenozoospermic (A) individuals was evaluated using RNA microarray followed by functional genomic analysis of differentially expressed genes. Results from A-F1 versus N-F1, A-F2 versus N-F2, N-F1 versus N-F2, and A-F1 versus A-F2 comparisons showed a considerably larger set of downregulated genes in tests versus controls.

Advanced Paternal Age Affects Sperm Count and Anogenital Distance in Mouse Offspring.

In Western society, couples increasingly delay parenthood until later in life. Overall, studies have focused on the reproductive performance of older parents or the impact of advanced maternal age on pregnancy outcomes, but few studies have examined how advanced paternal age (APA) affects offspring health. The aim of this study was to investigate the impact of increasing paternal age on offspring reproductive performance and long-term metabolic health in a mouse model.

A role for the chemokine receptor CCR6 in mammalian sperm motility and chemotaxis.

Although recent evidence indicates that several chemokines and defensins, well-known as inflammatory mediators, are expressed in the male and female reproductive tracts, the location and functional significance of chemokine networks in sperm physiology and sperm reproductive tract interactions are poorly understood. To address this deficiency in our knowledge, we examined the expression and function in sperm of CCR6, a receptor common to several chemoattractant peptides, and screened several reproductive tract fluids for the presence of specific ligands. CCR6 protein is present in mouse and human sperm and mainly localized in the sperm tail with other minor patterns in sperm from mice (neck and acrosomal region) and men (neck and midpiece regions).

Not all sperm are equal: functional mitochondria characterize a subpopulation of human sperm with better fertilization potential.

Human sperm samples are very heterogeneous and include a low amount of truly functional gametes. Distinct strategies have been developed to characterize and isolate this specific subpopulation. In this study we have used fluorescence microscopy and fluorescence-activated cell sorting to determine if mitochondrial function, as assessed using mitochondrial-sensitive probes, could be employed as a criterion to obtain more functional sperm from a given ejaculate.

A heterozygous mutation disrupting the SPAG16 gene results in biochemical instability of central apparatus components of the human sperm axoneme.

The SPAG16 gene encodes two major transcripts, one for the 71-kDa SPAG16L, which is the orthologue of the Chlamydomonas rheinhardtii central apparatus protein PF20, and a smaller transcript, which codes for the 35-kDa SPAG16S nuclear protein that represents the C-terminus (exons 11-16) of SPAG16L. We have previously reported that a targeted mutation in exon 11 of the Spag16 gene impairs spermatogenesis and prevents transmission of the mutant allele in chimeric mice. In the present report, we describe a heterozygous mutation in exon 13 of the SPAG16 gene, which causes a frame shift and premature stop codon, affording the opportunity to compare mutations with similar impacts on SPAG16L and SPAG16S for male reproductive function in mice and men.

Hormonal and embryonic regulation of chemokines IL-8, MCP-1 and RANTES in the human endometrium during the window of implantation.

Chemokines are a family of small polypeptides which specialize in the attraction of leukocytes. The presence of specific leukocyte subsets at the implantation site is an important element of the complex, and not completely understood, process of embryonic implantation. This report includes the investigation of the in-vivo immunolocalization and hormonal regulation of interleukin (IL)-8, monocyte chemotactic protein (MCP)-1 and RANTES (regulated upon activation normal T-cell expressed and secreted) in the human endometrium during hormone replacement therapy cycles for oocyte recipients in an IVF programme.