Effect of fructose on motility, acrosome reaction and in vitro fertilization capability of boar spermatozoa

Understanding the intricate impacts and mechanism of actions of adaptogens on reproductive function

Adaptogens, comprising plants and mushrooms, modulate the immune system, energy balance, and various physiological processes, including reproduction. Despite their potential benefits, the impact of adaptogens on reproductive function remains understudied. This review examines the effects of common adaptogens on male and female reproductive functions, highlighting their regulation of neuro-endocrine-immune interactions crucial for reproduction. While existing literature reveals varying impacts on reproductive function, most adaptogens exhibit beneficial effects, modulating neuroimmunology and promoting gonadal steroidogenesis, spermatogenesis, and folliculogenesis through direct mechanisms or suppression of oxidative stress and inflammation. Further experimental research is necessary to elucidate the mechanisms of action of adaptogens, which would significantly advance the management of reproductive disorders and other diseases. Validating these findings in clinical trials is also essential.

A systematic review identifying seminal plasma biomarkers and their predictive ability on IVF and ICSI outcomes

The diverse nature and high molecule concentration of seminal plasma (SP) makes this fluid a good potential source for a potential biomarker that could predict assisted reproductive technology (ART) outcomes. Currently, semen quality parameters cannot accurately predict ART outcomes. A systematic literature search was conducted to identify human SP biomarkers with potential predictive ability for the outcomes of IVF and intracytoplasmic sperm injection. Observational cohort and case-control studies describing the association between biomarkers in human SP and the outcome of infertile men attending for ART were included. Forty-three studies were selected, reporting on 89 potential SP biomarkers (grouped as oxidative stress, proteins glycoproteins, metabolites, immune system components, metals and trace elements and nucleic acids). The present review supports 32 molecules in SP as potentially relevant biomarkers for predicting ART outcomes; 23 molecules were reported once and nine molecules were reported in more than one study; IL-18 and TGF-β1-IL-18 ratio were confirmed in distinct studies. This review presents the most comprehensive overview of relevant SP biomarkers to predict ART outcomes to date, which is of clinical interest for infertility investigations and assisted reproduction; nevertheless, its potential is under-exploited. This review could serve as starting point for designing an all-encompassing study for biomarkers in SP and their predictive ability for ART outcomes, and for developing a non-invasive diagnostic tool.

Immune Checkpoint Proteins, Metabolism and Adhesion Molecules: Overlooked Determinants of CAR T-Cell Migration?

Adoptive transfer of T cells genetically engineered to express chimeric antigen receptors (CAR) has demonstrated striking efficacy for the treatment of several hematological malignancies, including B-cell lymphoma, leukemia, and multiple myeloma. However, many patients still do not respond to this therapy or eventually relapse after an initial remission. In most solid tumors for which CAR T-cell therapy has been tested, efficacy has been very limited. In this context, it is of paramount importance to understand the mechanisms of tumor resistance to CAR T cells. Possible factors contributing to such resistance have been identified, including inherent CAR T-cell dysfunction, the presence of an immunosuppressive tumor microenvironment, and tumor-intrinsic factors. To control tumor growth, CAR T cells have to migrate actively enabling a productive conjugate with their targets. To date, many cells and factors contained within the tumor microenvironment have been reported to negatively control the migration of T cells and their ability to reach cancer cells. Recent evidence suggests that additional determinants, such as immune checkpoint proteins, cellular metabolism, and adhesion molecules, may modulate the motility of CAR T cells in tumors. Here, we review the potential impact of these determinants on CAR T-cell motility, and we discuss possible strategies to restore intratumoral T-cell migration with a special emphasis on approaches targeting these determinants.

SERPIN A5 may have a potential as a biomarker in reflecting the improvement of semen quality in infertile men who underwent varicocele repair

We aimed to identify proteins that were differentially regulated in spermatozoal samples collected from fertile healthy men (FHM) and infertile patients with varicocele (IFPV) before and after varicocelectomy. Seminal samples were collected from 20 IFPV before and after varicocelectomy and from 14 FHM as controls. Samples underwent seminal examination and proteomic analysis. Extracted spermatozoal proteins were analysed using two-dimensional gel electrophoresis, and differentially regulated spermatozoal proteins (DRSPs) were identified. In particular, attention was placed on those DRSPs in which the concentration changed after varicocelectomy and corrected to approximate levels observed in FHM. Varicocelectomy significantly improved the sperm count and concentration in IFPV (p < 0.05). Proteomic analysis showed that 11 DRSPs were identified when comparisons were made among the three groups. Among these 11 proteins, change in the SERPIN A5 concentrations was notable because it was 100-fold downregulated in pre-operative IFPV samples and nearly resembled to control concentrations following varicocelectomy. Western blot analysis using an anti-SERPIN antibody validated the changes observed in SERPIN A5 levels before and after varicocelectomy operation. Increase in SERPIN A5 after varicocelectomy may be due to improvement in semen quality, suggesting that SERPIN A5 is a potential seminal biomarker for assessment of semen quality in varicocele-related infertility.

Metabolism of exogenous fatty acids, fatty acid-mediated cholesterol efflux, PKA and PKC pathways in boar sperm acrosome reaction

Purpose

For understanding the roles of fatty acids on the induction of acrosome reaction which occurs under association of cholesterol efflux and PKA or PKC pathways in boar spermatozoa, metabolic fate of alone and combined radiolabeled ¹⁴C-oleic acid and ³H-linoleic acid incorporated in the sperm was compared, and behavior of cholesterol and effects of PKA and PKC inhibitors upon fatty acid-induced acrosome reaction were examined.

Methods

Semen was collected from a Duroc boar, and the metabolic activities of fatty acids in the spermatozoa were measured using radioactive compounds and thin layer chromatography. Cholesterol efflux was measured with a cholesterol determination assay kit. Participation of fatty acids on the AR through PKA and PKC pathways was evaluated using a specific inhibitor of these enzymes.

Results

Incorporation rate of ¹⁴C-oleic acid into the sperm lipids was significantly higher than that of ³H-linoleic acid (P < 0.05). The oxidation of ¹⁴C-oleic acid was higher in combined radiolabeling rather than in one. The highest amounts of ³H-linoleic acid and ¹⁴C-oleic acid were recovered mainly in the triglycerides and phospholipids fraction, and ¹⁴C-oleic acid distribution was higher than the ³H-linoleic acid in both labeled (P < 0.05) sperm lipids. In the ³H-linoleic and ¹⁴C-oleic acid combined radiolabeling, the incorporation rate of the radioactive fatty acids in all the lipid fractions increased 15 times more than the alone radiolabeling. Boar sperm utilize oleic acid to generate energy for hyperactivation (P < 0.05). Supplementation of arachidonic acid significantly increased (P < 0.05) cholesterol efflux in sperm. When spermatozoa were incubated with PKA or PKC inhibitors, there was a significant reduction of arachidonic acid-induced acrosome reaction (AR) (P < 0.05), and inhibition by PKA inhibitor is stronger than that by PKC inhibitor.

Conclusions

Incorporation of unsaturated fatty acids, especially oleic acid, into triglycerides and phospholipids provides prerequisite energy for AR. Cholesterol efflux by arachidonic acid triggers AR. Arachidonic acid activated PKA and PKC pathway participate in induction of the AR.

The beneficial effect of fructose and glucose on in vitro maturation and the fertilization of porcine oocytes

Purpose

This study was conducted to investigate the effects of supplementing fructose in the culture medium on in vitro maturation (IVM), in vitro fertilization (IVF), and metabolism of porcine oocytes.

Methods

Porcine oocytes were matured in vitro in modified North Carolina State University 37 medium (NCSU-37) and then supplemented with either glucose (5.5 mM), fructose (5.5 mM), or glucose (2.75 mM) plus fructose (2.75 mM). The maturation and fertilization of oocytes, and the incorporation and oxidation of ¹⁴C-glucose, ¹⁴C-fructose, and ¹⁴C-methionine in oocytes at different stages of development were examined.

Results

The supplementation of glucose plus fructose significantly promoted (P < 0.05) oocytes germinal vesicle break down (GVBD), maturation to metaphase II (MII), penetration by spermatozoa, and male pronuclear formation compared with glucose. The incorporation and oxidation of ¹⁴C-methionine into the oocyte significantly increased (P < 0.05) with glucose plus fructose supplementation than glucose. A significantly higher (P < 0.05) rate of incorporation and oxidation was achieved with ¹⁴C-fructose compared to ¹⁴C-glucose.

Conclusions

Glucose plus fructose supplementation improved maturation, penetration by spermatozoa, male pronuclear formation, and energy metabolism by porcine oocytes.

Effect of amino acids and dipeptides on the acrosome reaction and accumulation of ammonia in porcine spermatozoa

Aim:  The present study was designed to investigate the effect of amino acids and their dipeptides in the medium related to the urea cycle on the motility, viability, acrosome reaction (AR) and accumulation of ammonia in the medium over different incubation periods in porcine spermatozoa and to assess the utilization of glucose. Methods:  Porcine spermatozoa were washed, swim-up and incubated at 37°C for 0-4 h in mTALP medium supplemented with 75-600 µmol/L ammonia. Amino acids (1.0 mmol) or their dipeptides (2.0 mmol) were added individually to the mTALP medium containing either no ammonia or 300 µmol/L of ammonia. The viability and AR of porcine spermatozoa were assessed using the triple-staining technique and the accumulation of ammonia in the medium was measured using the indophenol method. Results:  The motility, viability and AR were adversely affected (P < 0.05) by concentrations of ammonia ≥300 µmol/L compared with the control. Supplementation of l-alanyl-l-glutamine (AlaGln), l-glycyl-l-glutamine (GlyGln) and AlaGln + GlyGln in the presence of 300 µmol/L ammonia significantly increase (P < 0.05) the rate of motility, viability, AR, incorporation, accumulation of ammonia and oxidation of ¹⁴C(U)-glucose compared with the ammonia supplement control. Conclusion:  AlaGln and GlyGln in mTALP medium were more stable and effective than the individual amino acids in reducing the accumulation of ammonia, and subsequently increasing the rate of AR and the utilization of glucose in porcine spermatozoa. (Reprod Med Biol 2008; 7: 123-131).

Effect of fatty acids bound to bovine serum albumin-V on acrosome reaction and utilization of glucose in boar spermatozoa

Aim:  The present study has been designed with the objective of determining if fatty acids bound to bovine serum albumin-V (BSA-V) can improve motility, viability, and increase acrosome reaction (AR) and utilization of glucose in boar spermatozoa. Methods:  Boar spermatozoa were washed, swum-up and incubated at 37°C for 6 h in TALP medium supplemented with fatty acids bound to bovine serum albumin fraction V (BSA-V), fatty acid free BSA (BSA-FAF), polyvinyl alcohol + main fatty acids bound to BSA-V (PVA + FA) and PVA. Sperm motility, viability, AR, and the incorporation and oxidation of 14C-glucose were evaluated during 6 h of incubation. Results:  The results show that the BSA-V was superior to BSA-FAF and PVA in improving motility and AR. Viability was significantly increased (P < 0.05) by only BSA-V compared with PVA. When the main fatty acids compound of BSA-V were added to PVA, the sperm motility, viability and AR became almost the same as with BSA-V. The rate of incorporation and oxidation of 14C-glucose were significantly increased (P < 0.05) by BSA-V compared with BSA-FAF and PVA. Fatty acids bound to BSA-V are important for improvement of sperm functions. Conclusions:  The present study postulates that fatty acids bound to BSA-V are important to acrosome reaction and the utilization of glucose in boar spermatozoa.