P–042 Impact of semen parameters, sperm DNA fragmentation and sperm aneuploidy in male infertility

Study question

Should sperm aneuploidies and sperm DNA fragmentation (sDNAfrag) be included as valid tests in the routine investigation of male infertility?

Summary answer

Sperm DNA fragmentation was associated with male age, oligozoospermia (OZ), oligoteratozoospermia (OT), astenoteratozoospermia (AT) and oligoastenoteratozoospermia (OAT). Sperm aneuploidies were associated with OT and OAT.

What is known already

Semen parameters assist male infertility diagnosis and treatment, but sDNAfrag and aneuploidy analysis could add useful information, as abnormal values compromise fertility. To include these tests in the routine diagnosis it should be determined if behave as informative parameter and add information regarding the fertility status. For that, further studies comparing these tests to semen parameters are needed, since previous results are not consensual. Additionally, standardization of a sDNAfrag cut-off is needed, as different sample sizes and techniques originate distinct results. Also, until a standardization of the protocol is missing, a cut-off value should be defined for each laboratory.

Study design, size, duration

A retrospective and prospective investigation was performed, within a 12 years period (April 2007-December 2019). A total of 835 infertile males with a normal karyotype (46,XY) were included. Karyotyping and evaluation of sDNAfrag and sperm aneuploidies were made at a public Genetic unit. All normozoospermic (NZ) patients with a born child and patients whose infertility treatments were done due to female factors were selected from our database and used as controls (60 individuals).

Participants/materials, setting, methods

Semen analysis followed WHO–2010 guidelines. sDNAfrag was evaluated using the TUNEL assay. Sperm aneuploidies were detected using FISH (chromosomes 13, 18, 21, X, Y). Several tests were applied: correlations for linear associations between numerical variables, ANOVA for comparisons between means, Dunn-test for post-hoc comparisons. To determine the sDNAfrag cut-off value, the area under the ROC curve, sensitivity and specificity, were calculated, with the Youden-Index used to find a threshold that maximizes both sensitivity and specificity.

Main results and the role of chance

Regarding male age, it was observed a positive correlation with sperm concentration, a negative correlation with sperm vitality (VT) and hypoosmolality, and a positive correlation with sDNAfrag. Regarding sDNAfrag, it was observed negative correlation with sperm concentration, total progressive motility (TPM), morphology, VT and hypoosmolality. Regarding sperm aneuploidies, both total sperm aneuploidy and total sperm disomy exhibited a negative association with sperm concentration, TPM and morphology. It was also investigated whose groups of individuals could be indicated for sDNAfrag or sperm aneuploidy testing. The NZ group evidenced significant lower sDNAfrag, total sperm aneuploidy and total sperm disomy in relation to the non-NZ group. In the NZ group, sDNAfrag was significantly lower in relation to the OZ, OT, AT and OAT groups. The NZ group presented significant lower percentages of sperm aneuploidy in relation to the OT and OAT groups, and significant lower percentages of sperm disomy in relation to the OAT group. Additionally, sDNAfrag was positively correlated with total sperm aneuploidy and total sperm disomy. From the present large population, ROC curve analysis allowed estimating a cut-off value of 18.8% for the TUNEL-assay (sDNAfrag), with 0.658 of area under the curve, 53.9% sensitivity and 76.7% specificity.

Limitations, reasons for caution

Although presenting a high number of cases and strict controls, the present study was unable to include as controls healthy men with proven fertility. Additionally, the present study did not take into account life-style factors and male associated pathologies besides infertility.

Wider implications of the findings: Semen parameters were shown to be negatively correlated with sDNAfrag and sperm aneuploidies. As sDNAfrag testing and sperm aneuploidy testing were associated with semen abnormalities and male age, it is suggested their inclusion in the routine evaluation of infertile men, thus adding important complementary information about the fertility status.

Trial registration number

Not Appliable

Salivary nitric oxide and alpha-amylase as indexes of training intensity and load

This study examined the variation in salivary nitric oxide (NO), alpha-amylase (sAA) and serum markers of muscle injury during 21 weeks of training in elite swimmers. Samples of saliva and blood were collected once a month during 5 months from 11 male professional athletes during their regular training season. The variation in each marker throughout the 21 weeks was compared with the dynamics of training volume, intensity and load. Unstimulated whole saliva was assessed for NO and sAA whereas venous blood was assessed for lactate dehydrogenase, creatine kinase, and γ-glutamyltransferase. Nitric oxide and sAA showed a proportional response to the intensity of training. However, whereas the concentration of NO increased across the 21 weeks, the activity of sAA decreased. Similar variations in the concentration of NO and the markers of muscle injury were also observed. The higher concentration of NO might be attributed to changes in haemodynamics and muscle regenerative processes. On the other hand, autonomic regulation towards parasympathetic predominance might have been responsible for the decrease in sAA activity. These findings provide appealing evidence for the utilization of salivary constituents in sports medicine to monitor training programmes.

Response of salivary markers of autonomic activity to elite competition

We investigated the response of salivary total protein (TP), alpha-amylase (sAA) and chromogranin A (CgA) to sporting competition and their relation with positive and negative affect. 11 professional swimmers were examined during the first day of a national contest and on a recreated event that matched time-of-the-day and day-of-the-week assessments 2 weeks later. Total protein was determined by the Bradford method and sAA and CgA by Western blotting upon awakening, 30 and 60 min post awakening, immediately before warming up for competition and 5, 20 and 60 min after competition. Psychometric instruments included the Positive Affect and Negative Affect Schedule-X. The concentrations of TP, sAA and CgA differed from controls only prior to and 5 min after the event. We observed positive correlations between higher negative affect scores with higher levels of TP, sAA and CgA prior to the event on the competition day. All 3 markers showed a similar reactivity to sporting competition, which may be attributed to the mechanisms responsible for protein secretion into saliva when collection is performed with no exogenous stimulation. TP is an attractive marker in sports psychology since its determination is faster and cheaper than traditional kinetic or immune assays.

Purification of Bionanoparticles

The recent demand for nanoparticulate products such as viruses, plasmids, protein nanoparticles, and drug delivery systems have resulted in the requirement for predictable and controllable production processes. Protein nanoparticles are an attractive candidate for gene and molecular therapy due to their relatively easy production and manipulation. These particles combine the advantages of both viral and non‐viral vectors while minimizing the disadvantages. However, their successful application depends on the availability of selective and scalable methodologies for product recovery and purification. Downstream processing of nanoparticles depends on the production process, producer system, culture media and on the structural nature of the assembled nanoparticle, i.e., mainly size, shape and architecture. In this paper, the most common processes currently used for the purification of nanoparticles, are reviewed.

Vanadium and cadmium in vivo effects in teleost cardiac muscle: metal accumulation and oxidative stress markers

Several biological studies associate vanadium and cadmium with the production of reactive oxygen species (ROS), leading to lipid peroxidation and antioxidant enzymes alterations. The present study aims to analyse and compare the oxidative stress responses induced by an acute intravenous exposure (1 and 7 days) to a sub-lethal concentration (5 mM) of two vanadium solutions, containing different vanadate n-oligomers (n=1-5 or n=10), and a cadmium solution on the cardiac muscle of the marine teleost Halobatrachus didactylus (Lusitanian toadfish). It was observed that vanadium is mainly accumulated in mitochondria (1.33+/-0.26 microM), primarily when this element was administrated as decameric vanadate, than when administrated as metavanadate (432+/-294 nM), while the highest content of cadmium was found in cytosol (365+/-231 nM). Indeed, decavanadate solution promotes stronger increases in mitochondrial antioxidant enzymes activities (catalase: +120%; superoxide dismutase: +140%) than metavanadate solution. On contrary, cadmium increases cytosolic catalase (+111%) and glutathione peroxidases (+50%) activities. It is also observed that vanadate oligomers induce in vitro prooxidant effects in toadfish heart, with stronger effects induced by metavanadate solution. In summary, vanadate and cadmium are differently accumulated in blood and cardiac subcellular fractions and induced different responses in enzymatic antioxidant defence mechanisms. In the present study, it is described for the first time the effects of equal doses of two different metals intravenously injected in the same fish species and upon the same exposure period allowing to understand the mechanisms of vanadate and cadmium toxicity in fish cardiac muscle.

Decavanadate induces mitochondrial membrane depolarization and inhibits oxygen consumption

Decavanadate induced rat liver mitochondrial depolarization at very low concentrations, half-depolarization with 39 nM decavanadate, while it was needed a 130-fold higher concentration of monomeric vanadate (5 microM) to induce the same effect. Decavanadate also inhibits mitochondrial repolarization induced by reduced glutathione in vitro, with an inhibition constant of 1 microM, whereas no effect was observed up to 100 microM of monomeric vanadate. The oxygen consumption by mitochondria is also inhibited by lower decavanadate than monomeric vanadate concentrations, i.e. 50% inhibition is attained with 99 M decavanadate and 10 microM monomeric vanadate. Thus, decavanadate is stronger as mitochondrial depolarization agent than as inhibitor of mitochondrial oxygen consumption. Up to 5 microM, decavanadate does not alter mitochondrial NADH levels nor inhibit neither F(O)F(1)-ATPase nor cytochrome c oxidase activity, but it induces changes in the redox steady-state of mitochondrial b-type cytochromes (complex III). NMR spectra showed that decameric vanadate is the predominant vanadate species in decavanadate solutions. It is concluded that decavanadate is much more potent mitochondrial depolarization agent and a more potent inhibitor of mitochondrial oxygen consumption than monomeric vanadate, pointing out the importance to take into account the contribution of higher oligomeric species of vanadium for the biological effects of vanadate solutions.

Vanadium distribution, lipid peroxidation and oxidative stress markers upon decavanadate in vivo administration

The contribution of decameric vanadate species to vanadate toxic effects in cardiac muscle was studied following an intravenous administration of a decavanadate solution (1mM total vanadium) in Sparus aurata. Although decameric vanadate is unstable in the assay medium, it decomposes with a half-life time of 16 allowing studying its effects not only in vitro but also in vivo. After 1, 6 and 12h upon decavanadate administration the increase of vanadium in blood plasma, red blood cells and in cardiac mitochondria and cytosol is not affected in comparison to the administration of a metavanadate solution containing labile oxovanadates. Cardiac tissue lipid peroxidation increases up to 20%, 1, 6 and 12h after metavanadate administration, whilst for decavanadate no effects were observed except 1h after treatment (+20%). Metavanadate administration clearly differs from decavanadate by enhancing, 12h after exposure, mitochondrial superoxide dismutase (SOD) activity (+115%) and not affecting catalase (CAT) activity whereas decavanadate increases SOD activity by 20% and decreases (-55%) mitochondrial CAT activity. At early times of exposure, 1 and 6h, the only effect observed upon decavanadate administration was the increase by 20% of SOD activity. In conclusion, decavanadate has a different response pattern of lipid peroxidation and oxidative stress markers, in spite of the same vanadium distribution in cardiac cells observed after decavanadate and metavanadate administration. It is suggested that once formed decameric vanadate species has a different reactivity than vanadate, thus, pointing out that the differential contribution of vanadium oligomers should be taken into account to rationalize in vivo vanadate toxicity.

Vanadium distribution following decavanadate administration

An acute exposure of two vanadate solutions-metavanadate and decavanadate-containing different vanadate oligomers, induces different patterns of subcellular vanadium distribution in blood plasma, red blood cells (RBC), and cardiac muscle subcellular fractions of the fish Sparus aurata (gilthead seabream). The highest amount of vanadium was found in blood plasma 1 h after (5 mM) intravenous vanadate administration (295 +/- 64 and 383 +/- 104 microg V/g dry tissue, for metavanadate and decavanadate solutions, respectively), being 80-fold higher than in RBC. After 12 h of administration, the amount of vanadium in plasma, as well as in cardiac cytosol, decreased about 50%, for both vanadate solutions. During the period between 1 and 12 h, the ratio of vanadium in plasma/vanadium in RBC increased from 27 to 128 for metavanadate, whereas it remains constant (77) for decavanadate. Both vanadium solutions were primarily accumulated in the mitochondrial fraction (138 +/- 0 and 195 +/- 34 ng V/g dry tissue for metavanadate and decavanadate solutions, respectively, after 12 h exposure), rather than in cytosol. The amount of vanadium in cardiac mitochondria was twofold higher than in cytosol, earlier for metavanadate (6 h) than for decavanadate (12 h). It is concluded that, in fish cardiac muscle, the vanadium distribution is dependent on the administration of decameric vanadate, with vanadium being mainly distributed in plasma, before being accumulated into the mitochondrial fraction.

Vanadate oligomers: in vivo effects in hepatic vanadium accumulation and stress markers

The formation of vanadate oligomeric species is often disregarded in studies on vanadate effects in biological systems, particularly in vivo, even though they may interact with high affinity with many proteins. We report the effects in fish hepatic tissue of an acute intravenous exposure (12, 24 h and 7 days) to two vanadium(V) solutions, metavanadate and decavanadate, containing different vanadate oligomers administered at sub-lethal concentration (5 mM; 1 mg/kg). Decavanadate solution promotes a 5-fold increase (0.135 +/- 0.053 microg V(-1) dry tissues) in the vanadium content of the mitochondrial fraction 7 days after exposition, whereas no effects were observed after metavanadate solution administration. Reduced glutathione (GSH) levels did not change and the overall reactive oxygen species (ROS) production was decreased by 30% 24 h after decavanadate administration, while for metavanadate, GSH levels increased 35%, the overall ROS production was depressed by 40% and mitochondrial superoxide anion production decreased 45%. Decavanadate intoxication did not induce changes in the rate of lipid peroxidation till 12 h, but later increased 80%, which is similar to the increase observed for metavanadate after 24 h. Decameric vanadate administration clearly induces different effects than the other vanadate oligomeric species, pointing out the importance of taking into account the different vanadate oligomers in the evaluation of vanadium(V) effects in biological systems.

Cadmium and vanadate oligomers effects on methaemoglobin reductase activity from Lusitanian toadfish: in vivo and in vitro studies

Cadmium and two vanadate solutions as 'metavanadate' (containing ortho and metavanadate species) and 'decavanadate' (containing decameric species) (5 mM) were injected intraperitoneously in Halobatrachus didactylus (Lusitanian toadfish), in order to evaluate the effects of cadmium and oligomeric vanadate species on methaemoglobin reductase activity from fish red blood cells. Following short-term exposure (1 and 7 days), different changes were observed on enzyme activity. After 7 days of exposure, 'metavanadate' increased methaemoglobin reductase activity by 67% (P < 0.05), whereas, minor effects were observed on enzymatic activity upon cadmium and 'decavanadate' administration. However, in vitro studies indicate that decameric vanadate, in concentrations as low as 50 microM, besides strongly inhibiting methaemoglobin reductase activity, promotes haemoglobin oxidation to methaemoglobin. Although decameric vanadate species showed to be unstable in the different media used in this work, the rate of decameric vanadate deoligomerization is in general slow enough, making it possible to study its effects. It is concluded that the increase in H. didactylus methaemoglobin reductase activity is more pronounced upon exposition to 'metavanadate' than to cadmium and decameric species. Moreover, only decameric vanadate species promoted haemoglobin oxidation, suggesting that vanadate speciation is important to evaluate in vivo and in vitro effects on methaemoglobin reductase activity.

Kaempferol glycosides from Siparuna apiosyce

The kaempferol derivative 3,7-di-O-methyl-4'-O-beta-[alpha rhamnosyl (1 --> 6)]-glucopyranoside (siparunoside) was isolated from the leaves of Sparuna apiosyce. Its structure was established by extensive NMR studies. The alkaloids reticuline and liriodenine were also isolated from the leaves along with the kaempferol derivative tiliroside. Benzylisoquinoline alkaloids were isolated from the wood (liriodenine) and wood bark (liriodenine, laurotetanine, N-methyl-laurotetanine, reticuline), together with a mixture of cis and trans-N-feruloyltyramines. 3,7,4'-tri-O-methylkaempferol was isolated from all organs.

Chemistry and pharmacology of Monimiaceae: a special focus on Siparuna and Mollinedia

The chemistry and pharmacology of species of the family Monimiaceae are reviewed, with special attention given to the genera Mollinedia and Siparuna, the two most important and representative in Brazil. The isolation of benzylisoquinoline alkaloids and kaempferol derivatives from Siparuna apiosyce is reported, as well as the isolation of aporphines from the fruits of Siparuna arianeae. Cinnamic acid derivatives and a gamma-lactone were isolated from Mollinedia gilgiana and Mollinedia marliae.