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The high overwinter mortalities in the honey bee population of Apis mellifera have been linked to immunocompromised individuals experiencing nutritional limitations. Larval nutrition plays a crucial role in determining the successful development of adults, making them more susceptible to bacterial diseases when undernourished. One of the main intracellular signalling pathways in the larval immune system against bacterial diseases is the Toll receptor signalling pathway, which activates antimicrobial peptides like defensin. Inadequate nutrition also disrupts the redox balance on A. mellifera individuals, with superoxide dismutase and catalase being the key components of their antioxidant system. Vitellogenin is associated with the mobilization of nutrients in early A. mellifera bee stages. Considering that Saccharomyces cerevisiae is the second most significant by‐product of the brewing industry, it may serve as a valuable raw material. We investigated the impact of feeding larvae with live S. cerevisiae cells on the relative expression of their main immune and antioxidant‐related genes. To assess gene expression, we conducted RT‐qPCR, using RNA extracted from ten larvae per treatment on the seventh day when the feeding trial concluded. Importantly, the presence of S. cerevisiae did not affect larval survival compared to the control group. However, the relative expression of immune‐related gene toll18W and antioxidant‐related gene sod in larvae fed with live S. cerevisiae cells was significantly higher than in larvae that were not fed with them. This suggests that the inclusion of S. cerevisiae in their diet may provide larvae with a nutritional advantage. Additionally, the vitellogenin (vg) gene expression increased in treated larvae compared to the control group, potentially facilitating their access to nutrients and, consequently, enhancing their ability to cope with nutritional stress. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare the endometrial gene expression of epidermal growth factor receptor (EGFR), nodal growth differentiation factor (NODAL), prostaglandin‐endoperoxide synthase 2 (PTGS2), oestrogen receptor 1 (ESR1) and progesterone receptor (PGR) in repeat breeder cows (RBC) and non‐RBC during diestrus. Endometrial samples were collected by cytobrush technique and stored in RNA stabilizing solution at −20°C until RT‐qPCR analysis. Differences in endometrial mRNA expression of selected genes were assessed by ANOVA and simple (r) and the partial correlations (rp) among selected genes were performed. Results demonstrated that mRNA expression of EGFR and NODAL were higher in RBC than in non‐RBC (3 and 25‐fold change, p <.01 and p <.01, respectively), while the mRNA expression of PTGS2 was lower (1.56‐fold change, p <.01). Although there were no differences detected in the mRNA expression of ESR1 and PGR, there was a positive correlation between the expression of ESR1 and EGFR (0.84, p <.05) and a negative correlation between PGR and PTGS2 (−0.49, p <.05). In conclusion, the difference on the endometrial mRNA expression of the genes included in the study between RBC and non‐RBC indicates a deregulation of important mechanisms that are vital to establish a successful pregnancy. Thus, the present study provides useful insight as a base for future studies to elucidate the causes of RBC. [ABSTRACT FROM AUTHOR]

Energy balance is regulated by ghrelin which is a neuroendocrine modulator. Ghrelin is expressed in reproductive organs. However, the role of ghrelin during in vitro maturation (IVM) and bovine preimplantational development is limited. The purpose of this study was to measure the expression of ghrelin (GHRL) and its receptor growth hormone secretagogue receptor 1A (GHS-R1A) mRNA, and determine cumulus oocyte complex (COC) viability after IVM with 0, 20, 40 and 60 pM of ghrelin. Also, pronuclear formation was recorded after in vitro fertilization (IVF). GHRL and GHS-RIA mRNA expression in oocyte and cumulus cells (CCs) was assessed using reverse transcription-polymerase chain reaction (PCR). Oocyte and CC viability were analyzed with the fluorescein diacetate fluorochrome-trypan blue technique. Pronuclear formation was determined 18 hours after IVF with Hoechst 33342. The results demonstrated that ghrelin mRNA is present in oocyte and CCs before and after 24 hours IVM with all treatments. Ghrelin receptor, GHS-R1A, was only detected in oocytes and CCs after 24 hours IVM with 20, 40 and 60 pM of ghrelin. Oocyte viability was not significantly different (P=0.77) among treatments. However, CC viability was significantly lower (P=0.04) when cOCs were matured with ghrelin (77.65, 72.10, 66.32 and 46.86% for 0, 20, 40, and 60 pM of ghrelin, respectively). The chance of two pronuclei forming were higher (P=0.03) when ghrelin was not be added to the IVM medium. We found that ghrelin negatively impacts CC viability and pronuclear formation. [ABSTRACT FROM AUTHOR]

Zinc (Zn) is a vital trace element for the body and its bioavailability influences numerous reproductive events. However, the mechanisms that regulate Zn homeostasis in the cumulus-oocyte complex (COC) are yet to be elucidated. The aim of this study was to investigate the role of estradiol 17-beta (E 2), FSH and LH in Zn homeostasis regulation in bovine COC matured in vitro and Zn transporters gene expression. For this purpose, intracellular Zn levels in oocytes and cumulus cells (CC) were assessed using a Zn-specific fluorescent indicator. In addition, gene expression and sequencing of six Zn transporters (Slc39a6, Slc39a8, Slc39a14, Slc30a3, Slc30a7 and Slc30a9) were assessed. Our results demonstrated that the simultaneous presence of E 2 , FSH, and LH during oocyte maturation altered intracellular zinc levels and transporters expression in both oocytes and CC. Transporter's gene expression was different in oocytes and CC, possibly due to cell-specific changes in Zn levels during maturation. The interaction effects of Zn with hormonal treatments influenced the results. This study emphasizes that Slc39a6 is highly sensitive to hormone induction. Overall, the hormonal modulation of Zn homeostasis in the COC was evidenced. Also, a preponderant role of FSH as a modulator of Zn intracellular levels and transporter gene expression is suggested. • Zinc availability is beneficial for follicular growth, oocyte maturation, fertilization, and embryo development. • Reproductive hormones affected Zn homeostasis and gene expression of Zn transporters during IVM of bovine COC. • The gene expression of Zn transporters in oocytes and cumulus cells were different. • The role of FSH in the modulation of intracellular Zn levels and transporter gene expression is evident. • The Zn transporter Slc39a6 is highly sensitive to hormonal regulation. [ABSTRACT FROM AUTHOR]

Objective: To study expression of dysadherin in human testis, epididymis, and spermatozoa. Design: Prospective study. Setting: Basic research laboratory. Patient(s): Testis, epididymis, and testicular spermatozoa from patients under treatment and semen from volunteer donors. Intervention(s): Reverse transcription–polymerase chain reaction, immunohistochemistry, immunocytochemistry, and Western immunoblotting. Main Outcome Measure(s): Dysadherin messenger RNA (mRNA) analysis in testis, epididymis, and ejaculated spermatozoa, immunohistochemistry of both tissues, Western immunoblotting of tissue/cell extracts, and immunocytochemistry of spermatozoa. Result(s): Dysadherin mRNA was found in testis, epididymis, and ejaculated spermatozoa. Whereas testis and spermatozoa exhibited a distinctive 91-kDa protein form, the epididymis showed a 50-kDa moiety, also found in MDA-MB-231 breast cancer cells. Nucleotide sequence analysis revealed >99% homology between testicular and somatic cell mRNA, suggesting differential protein glycosylation. Dysadherin was immunodetected in round spermatids and testicular/ejaculated spermatozoa. It localizes to the acrosomal region and flagellum and colocalized with E-cadherin in the head and with the Na+,K+-ATPase α4 subunit in the flagellum. Conclusion(s): This is the first report on expression of dysadherin in the male gonad and in spermatozoa. Its colocalization with E-cadherin and Na+,K+-ATPase leads us to postulate a role for dysadherin as a modulator of sperm function. [Copyright &y& Elsevier]