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A study was conducted to analyze the transcriptional effects of core histone tail absence by oligonucleosomal templates and bacteriophage T7 RNA polymerase. Different DNA molecules were utilized to prepare the oligonucleosomal structures that were utilized as transcription templates. A Beckman XL-A analytical ultracentrifuge was used to perform sedimentation velocity and equilibrium experiments. Results showed that the eradication of histone terminal domains influences RNA synthesis under various salt conditions and in the presence and absence of spermidine.

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. Gene ontology (GO) analysis of A–F1 versus N–F1 identified 507 overrepresented biological processes (BPs), several of which are associated with sperm physiology. In addition, gene set enrichment analysis of the same contrast showed 110 BPs, 36 cellular components, and 31 molecular functions, several of which are involved in sperm motility. A leading-edge analysis of selected GO terms resulted in several downregulated genes encoding to dyneins and kinesins, both related to sperm physiology. Furthermore, the predicted activation state of asthenozoospermia was increased, while fertility, cell movement of sperm, and gametogenesis were decreased. Interestingly, several downregulated genes characteristic of the canonical pathway protein ubiquitination were involved in asthenozoospermia activation. Conversely, GO analysis of A–F2 versus N–F2 did not identify overrepresented BPs, although the gene set enrichment analysis detected six enriched BPs, one cellular component, and two molecular functions. Overall, the results show differences in gene transcription between sperm subpopulations from asthenozoospermic and normozoospermic semen samples and allowed the identification of gene sets relevant to sperm physiology and reproduction. [ABSTRACT FROM AUTHOR]

Background: Plasma membranes of ejaculated sperm are covered by epididymal and accessory glands secreted proteins that must be released from sperm surface during the female reproductive tract passage in order to capacitate and fertilize the oocyte. Objectives: As human sperm plasma membrane‐associated proteins (SMAP) have not yet been investigated, the aim of this study was to characterize the SMAP released during in vitro human capacitation and to study their possible role as decapacitation factors. Materials and Methods: SMAP were characterized by 2‐dimensional electrophoresis and mass spectrometry analysis. Besides, we explored SMAP effects on motility, protein tyrosine phosphorylation, and calcium ionophore‐induced acrosome reaction of spermatozoa either incubated for 6 h in capacitating medium ± SMAP or for 5 h in capacitating medium alone followed by incubation for 1 h ± SMAP. Results: Mass spectrometry analysis allowed the identification of 29 proteins, all of which have previously been identified in the human seminal fluid. Spermatozoa incubated for 6 h under capacitating conditions in the presence of the SMAP showed a significant decrease in the incidence of non‐progressive motility, hyperactivation, protein tyrosine phosphorylation, and calcium ionophore‐induced acrosome reaction. However, spermatozoa incubated for 5 h in capacitating medium and further incubated for 1 h with the SMAP showed a lower percentage of spermatozoa with non‐progressive motility and hyperactivated cells but no effects on protein tyrosine phosphorylation were detected. Discussion and Conclusions: Our results indicate that SMAP inhibit the progress of human sperm capacitation, but only motility changes related to capacitation may be reversed by these proteins. The study of the identified proteins on sperm function and their mechanisms of action on this cell may contribute to the understanding of their role during capacitation. [ABSTRACT FROM AUTHOR]

The acrosome reaction (AR), an absolute requirement for spermatozoa and egg fusion, requires the influx of Ca2+ into the spermatozoa through voltage-dependent Ca2+ channels and store-operated channels. Maitotoxin (MTx), a Ca2+-mobilizing agent, has been shown to be a potent inducer of the mouse sperm AR, with a pharmacology similar to that of the zona pellucida (ZP), possibly suggesting a common pathway for both inducers. Using recombinant human ZP3 (rhZP3), mouse ZP and two MTx channel blockers (U73122 and U73343), we investigated and compared the MTx- and ZP-induced ARs in human and mouse spermatozoa. Herein, we report that MTx induced AR and elevated intracellular Ca2+ ([Ca2+]i) in human spermatozoa, both of which were blocked by U73122 and U73343. These two compounds also inhibited the MTx-induced AR in mouse spermatozoa. In disagreement with our previous proposal, the AR triggered by rhZP3 or mouse ZP was not blocked by U73343, indicating that in human and mouse spermatozoa, the AR induction by the physiological ligands or by MTx occurred through distinct pathways. U73122, but not U73343 (inactive analogue), can block phospholipase C (PLC). Another PLC inhibitor, edelfosine, also blocked the rhZP3- and ZP-induced ARs. These findings confirmed the participation of a PLC-dependent signalling pathway in human and mouse zona protein-induced AR. Notably, edelfosine also inhibited the MTx-induced mouse sperm AR but not that of the human, suggesting that toxin-induced AR is PLC-dependent in mice and PLC-independent in humans. [ABSTRACT FROM AUTHOR]

Presents information on a study which evaluated the expression of mammalian zona pellucida during ovarian development. Materials and methodology of the study; Results and discussion of the study.

Human chorionic gonadotropin (hCG) is an essential hormone for development and sustaining of gestation. Adequate hCG production is fundamental for pregnancy success since abnormal hCG serum concentrations have been correlated with pregnancy anomalies such as recurrent abortions and preeclampsia. Regulation of hCG production involves diverse molecules associated with different signaling pathways, which have complicated the establishment of the mechanisms involved in its production. The present study provides a critical review of the most relevant findings related to hCG production and functions during pregnancy, in order to help to understand some related pathologies and to treat them more adequately.

The establishment of the impact of environmental compounds or additives with hormone-like activity on human health still requires further investigation, as well as a reexamination of biologic models and experimental methodology employed so far. In 1988, the FAO/WHO Expert Committee on Food Additives Joint with the Federal Drug Administration (FDA) considered that sexual hormone residues usually present in meat do not represent a risk for human consumption. Nevertheless, this resolution seems to be uncertain since the scientific elements employed for this statement may not be adequate. In this review the principal objections to the evidence used to establish the innocuousness of growth promoter hormones are considered.