Seminal antioxidants in humans: preoperative and postoperative evaluation of coenzyme Q10 in varicocele patients.

Coenzyme Q10 in seminal fluid shows a direct correlation with seminal parameters except in patients with varicocele. To evaluate whether surgical treatment of varicocele could revert CoQ10 abnormalities, we have studied CoQ10 distribution in thirty-three VAR patients, before and 6-8 months after varicocelectomy, twenty patients with idiopathic oligozoospermia, eleven with isolated asthenozoospermia and sixteen normal fertile men. CoQ10 was assayed in total seminal fluid, plasma or cell pellet by HPLC. A significantly higher CoQ10 proportion in seminal plasma in VAR vs. controls (mean +/- SEM: 61.68 +/- 2.41 vs. 41.60 +/- 1.99%, respectively) was present; total CoQ10 correlated with sperm motility in controls, but not in VAR; an inverse correlation between cellular CoQ10 and motility was present in VAR, but not in controls. Postoperatively, a partial reversion was observed, since the plasma-to-total CoQ10 ratio decreased, but the correlation between total CoQ10 and motility was not restored. On the contrary, the peculiar correlation between cellular CoQ10 and motility was no more detectable in postoperative VAR patients. A partial postoperative reversal of abnormalities in CoQ10 distribution and correlation with seminal parameters was therefore present. As seminal plasma CoQ10 reflects an interchange between intracellular and extracellular compartments, its different distribution could cause a greater sensitivity to peroxidative damage and a reduced utilization for energetic purpose.     

An update of Coenzyme Q10 implications in male infertility: biochemical and therapeutic aspects

This review is focused upon the role of coenzyme Q(10) in male infertility in the light of a broader issue of oxidative damage and antioxidant defence in sperm cells and seminal plasma. Reactive oxygen species play a key pathogenetic role in male infertility besides having a well-recognized physiological function. The deep involvement of coenzyme Q(10) in mitochondrial bioenergetics and its antioxidant properties are at the basis of its role in seminal fluid. Following the early studies addressing its presence in sperm cells and seminal plasma, the relative distribution of the quinone between these two compartments was studied in infertile men, with special attention to varicocele. The reduction state of CoQ(10) in seminal fluid was also investigated. After the first in vitro experiments CoQ(10) was administered to a group of idiopathic asthenozoospermic infertile patients. Seminal analysis showed a significant increase of CoQ(10) both in seminal plasma and in sperm cells, together with an improvement in sperm motility. The increased concentration of CoQ(10) in seminal plasma and sperm cells, the improvement of semen kinetic features after treatment, and the evidence of a direct correlation between CoQ(10) concentrations and sperm motility strongly support a cause/effect relationship. From a general point of view, a deeper knowledge of these molecular mechanisms could lead to a new insight into the so-called unexplained infertility.     

Lipid profiles of sperm and seminal plasma from boars having normal or low sperm motility

Sperm plasma membrane lipids have an important role to play in determining membrane fluidity and sperm motility. The objective of the present study was to determine whether there are differences in the lipid and fatty acid (FA) composition of boar sperm and seminal plasma in the ejaculates of boars having different sperm motilities. Semen was collected from two groups of boars having normal (> 60%; n = 53) or low (< 60%; n = 53) motility sperm and the semen was evaluated for motility, morphology and vitality. The semen was then centrifuged to separate the sperm from the seminal plasma and both were kept at −20 °C until analyzed for lipid content and FA profile by gas chromatography. Total antioxidant status (TAS) of seminal plasma was determined using a commercial kit. There were differences (P ≤ 0.05) in sperm total lipids, cholesterol, saturated fatty acids (SFA), phospholipids, n-3 polyunsaturated fatty acids (PUFA), docosahexaenoic acid (DHA) and the ratio of n-6:n-3 PUFA between boars with normal and low motility sperm. Total lipids, cholesterol, phospholipids, PUFA, DHA and n-3 PUFA were positively correlated with sperm motility, viability, normal morphology and normal plasma membrane. In contrast, SFA and the ratio of n-6: n-3 PUFA were negatively correlated (P ≤ 0.05) with sperm motility, viability, normal morphology and normal plasma membranes. The TAS of seminal plasma from boars having normal motility sperm was higher (P ≤ 0.05) than that of boars having low motility sperm and TAS was positively correlated (P = 0.0001) with sperm motility, viability, normal morphology and normal plasma membranes. In summary, differences in sperm motility were related to n-3 PUFA content in the sperm plasma membrane and extracellular antioxidants in seminal plasma which protect sperm plasma membranes from lipid peroxidation during periods of oxidative stress.     

Blood Serum and Seminal Plasma Selenium,Total Antioxidant Capacity and Coenzyme Q10 Levels in Relation to Semen Parameters in Men with Idiopathic Infertility

In this case–control study, we aimed to evaluate the serum and seminal plasma levels of Selenium (Se), total antioxidant capacity (TAC), and Coenzyme Q10 (CoQ-10) and determine their relationship with sperm concentration, motility, and morphology in men with idiopathic infertility. A total of 59 subjects were enrolled in the study. Forty four patients were diagnosed with idiopathic male infertility and had abnormal sperm parameters, and 15 subjects had normal sperm parameters with proven fertility. Serum Se, semen Se, and semen TAC levels were significantly different in the fertile and infertile groups (p?<?0.01, p?<?0.001, and p?<?0.001, respectively). However, serum TAC, serum, and seminal plasma CoQ-10 levels did not differ between fertile and infertile groups. When the levels of the measured parameters were compared in serum and seminal plasma, serum levels of Se were found to be correlated positively with the semen levels in all subjects included into the study (N?=?59) (r?=?0.46, p?<?0.01). A relationship was found between neither serum and semen levels of TAC nor between serum and semen levels of CoQ-10. Correlations among measured serum and semen parameters with sperm parameters demonstrated that both the serum and semen levels of Se were correlated positively with spermatozoa concentration, motility, and morphology. Additionally, seminal plasma levels of TAC correlated positively with all these sperm parameters. On the other hand, seminal plasma levels of CoQ-10 correlated only with sperm morphology but not with concentration or motility. No relationship was observed between serum levels of TAC or serum levels of CoQ-10 and sperm parameters. In conclusion, serum and seminal plasma Se deficiency may be a prominent determinant of abnormal sperm parameters and idiopathic male infertility. Measurement of serum Se levels may help determine nutritional status and antioxidant capacity in infertile patients, which may help distinguish those patients who will benefit from supplementation therapy.     

Proteomic analysis of seminal extracellular vesicle proteins involved in asthenozoospermia by iTRAQ

Asthenozoospermia is a common cause of male infertility, but in most cases its etiology is unknown. The exocytic cell vesicles called seminal extracellular vesicles in the human seminal fluid have been reported to play a pivotal role in promoting the motility of spermatozoa, and functional disorder of seminal extracellular vesicles may cause male infertility. To determine whether abnormal seminal extracellular vesicles are involved in asthenozoospermia, the differential abundance proteins between normozoospermic (NSEV) and asthenozoospermic seminal extracellular vesicles (ASEV) samples were analyzed by iTRAQ coupled with two‐dimensional liquid chromatography–tandem mass spectrometry. A total of 3,699 proteins were identified in the seminal extracellular vesicles (false discovery rate <0.01). Overall, 11 proteins were significantly upregulated (>1.2) in ASEV and 80 were significantly downregulated (<0.833). Functional bioinformatic analysis showed that these proteins with differential abundance were mainly associated with transport, metabolism, and signal pathways. The changes of OPTN, SMYD2, EIF2B2, TRPV6, ACE, PRSS8, and PPAP2A in ASEV were verified by western blot analysis, and we found that the abundance of TRPV6 markedly reduced in the seminal extracellular vesicles and ejaculated spermatozoa of asthenozoospermic patients, which indicated trpv6 was important in sperm motility. This study provides deeper insight into the involvement of seminal extracellular vesicles in asthenozoospermia and should aid the search for novel biomarkers of male infertility.     

Heterogeneous Immunolocalisation of Zinc Transporters ZIP6, ZIP10 and ZIP14 in Human Normo- and Asthenozoospermic Spermatozoa

Zinc (in the form of Zn²⁺) is necessary for male fertility. Both Zn²⁺ quantity and its localisation have been detected in seminal plasma and ejaculated spermatozoa, suggesting its active uptake via zinc import transporters (ZIPs). Immunofluorescence was used to characterise the expression and localisation of three distinct types of ZIP transporters in ejaculated spermatozoa of normo- and asthenozoospermic sperm samples. ZIP6, ZIP10 and ZIP14 showed heterogeneous sperm cell expression and different compartmental distribution. In both types of sperm samples, ZIP6 and ZIP14 were predominantly localised in the sperm head, while ZIP10 was found along the sperm tail. Compartmental localisation of ZIPs in asthenozoospermia was not changed. However, regarding sub-compartmental localisation in sperm head regions, for ZIP6 asthenozoospermia only decreased its acorn/crescent-like pattern. In contrast, ZIP14 immunostaining was altered in favour of crescent-like, as opposed to acorn-like and acorn/crescent-like patterns. The specific ZIPs localisation may reflect their different roles in sperm cell integrity and motility and may change over time. This is the first report of their specific compartmental and sub-compartmental localisation in ejaculated human sperm cells. Further research will lead to a greater understanding of the roles of ZIPs in sperm cell biology, which could positively influence procedures for human infertility therapy.     

Tissue kallikrein activity in seminal plasma of bovine ejaculates with different quality

Tissue kallikrein activity was monitored in seminal plasma from 3 groups of bovine ejaculates: those with normal total sperm motility (78.43%), with reduced sperm motility (49.29%), and with reduced sperm count (0.68 x 10(9) cells/ml). The tissue kallikrein activity was measured spectrophotometrically by using the specific chromogenic substrate S-2266. It was found that the semen samples with normal sperm motility manifested 1.083 microkat/L, on an average, or 29% higher than the activity recorded in ejaculates with reduced sperm motility (P < 0.05). After storage of a group of ejaculates of normal quality for 5 h at room temperature, sperm motility dropped by approximately 80%, expressed as a percentage of the initial motility, while the tissue kallikrein activity in the respective seminal samples decreased by 23%. No significant differences were found in kallikrein activity between ejaculates with normal and reduced sperm counts. It is concluded that a relationship exists between the level of tissue kallikrein activity in the seminal plasma of bovine ejaculates and sperm motility.     

Idebenone improves quality of ram sperm by mitigating oxidative stress during cryopreservation

The present study was designed to test the effect of different levels of idebenone, a potent antioxidant on the quality of ram semen at post thaw. Eighteen (18) ejaculates were collected and extended with tris extender supplemented with no antioxidant (CON), with 2 μM idebenone (Id2), 5 μM idebenone (Id5), 7.5 μM idebenone (Id7.5) and 10 μM idebenone (Id10). The sperm quality was determined in terms of percent sperm motility, live sperm percentage, percent hypoosmotic swelling test (HOST) positive spermatozoa and percent intact acrosome (PIA). Moreover, malondialdehyde (MDA) level, an end product of lipid peroxidation (LPO) was also measured at post thaw both in seminal plasma and sperm cell. At post thaw, the percent sperm motility was significantly higher (p < 0.05) for Id10 as compared to Id2, Id5, Id7.5 and control. The live sperm percentage was non-significantly (p > 0.05) higher for Id10 as compared to control, Id5 and Id7.5 but significantly higher than Id2. The percent HOST positive spermatozoa was significantly higher (p < 0.05) for Id10 than control, Id2 and Id5. The MDA level in seminal plasma was significantly lower (p < 0.05) for Id10 than control and Id2. The MDA level in spermatozoa did show similar trend as in seminal plasma. Further, all the sperm parameters at all idebenone levels declined significantly from pre freeze to post thaw. In conclusion, idebenone at 10 μM level improved post thaw sperm quality by mitigating peroxidative stress, hence could be considered as a promising antioxidant additive for cryopreservation of ram semen.     

Factors affecting the removal of low-molecular-weight fractions (LMWF) from egg yolk and seminal plasma in extended semen by dialysis: effect on post-thaw sperm survival

Three factors affecting dialysis of bovine semen were studied. These factors were (1) dialysis rates of egg yolk, seminal plasma, and glycerol, (2) temperature (37 degrees C, 5 degrees C, and while cooling from 37 to 5 degrees C), and (3) dialysis ratios between retentate and dialysate (1:1, 1:10, 1:20, 1:50, and 1:100). Ninety percent of the low-molecular-weight fraction (LMWF) from seminal plasma, egg yolk, and glycerol was removed from the retentate in a 2-hr period at 5 degrees C, and only slight changes were detected after the third hour of dialysis. Temperature affected dialysis and was faster at 37 degrees C. It was also found that a 1:20 dialysis ratio was sufficient to obtain 90% clearance of the LMWF. The effect of sperm dilution ratio, dialysis ratio, and exchange of the LMWF from egg yolk and/or seminal plasma for buffer systems was also studied. An improvement in post-thaw motility of spermatozoa (P less than 0.05) was obtained when the LMWF from both seminal plasma and egg yolk were replaced. A third experiment was conducted to study the effect of different combinations between the buffer systems, TEST and Na citrate, in the dialysate. The results indicated that a 1:1 combination of iso-osmotic solutions (320-325 mOsm/Kg, pH 7.0) between these two buffers, with 5% glycerol (v/v), yielded significant (P less than 0.05) sperm post-thaw motility as compared with the individual use of TEST-glycerol or Na citrate-glycerol. Dialyzed samples also yielded sperm post-thaw motility higher than that of the nondialyzed samples. Colloidal materials in the dialysate did not affect survival of spermatozoa.     

Total reactive antioxidant potential and DNA fragmentation index as fertility sperm parameters

There is a growing evidence that oxidative stress play a major role in the etiology of defective sperm function including impaired morphology, motility, metabolism and fertility. The aim of the present study was to examine: 1/ total reactive antioxidant potential (TRAP) in seminal plasma; 2/ sperm DNA fragmentation index (DFI), 3/ sperm morphology and motility and 4/ cellular membrane integrity (hypoosmotic swelling test: HOS test) in patients attending in vitro fertilization/intracytoplasmatic sperm injection ( IVF/ICSI) program. According to the DFI value, the men were divided into: group 1 with DFI ≤15% (n=38) and group 2 with DFI ≥15% (n=37). Significant differences between the two groups were found in TRAP, sperm motility, morphology and concentration as well as HOS test scores. In group 1, DFI was negatively correlated with sperm motility and HOS test scores (p<0.05). The sperm morphology was positively correlated with sperm motility and HOS test scores in both groups. There was no correlation between TRAP and sperm chromatin fragmentation. Our results suggest that seminal plasma TRAP level may be a DFI independent parameter of sperm fertility.     

The effect of seminal plasma on alpaca sperm function

In order to advance the development of assisted reproductive technologies in alpacas and other Camelids, the objective of this study was to explore the role of seminal plasma concentration on motility and functional integrity of alpaca sperm. Sixteen male alpacas > 3 y of age were used. In Experiment 1, epididymal sperm were incubated for 0 to 6 h in 0, 10, 25, 50, or 100% seminal plasma and motility was assessed. In Experiment 2, epididymal sperm were incubated in 0, 10, or 100% seminal plasma for 3 h and motility, acrosome integrity and DNA integrity were assessed. In Experiment 3, ejaculated sperm were incubated in 10, 25, 50, or 100% seminal plasma for 0 to 6 h and motility assessed. In Experiment 4, ejaculated sperm were incubated in 10 or 100% seminal plasma for 3 h and motility, acrosome integrity, DNA integrity, and viability were assessed. Epididymal and ejaculated sperm maintained motility longer when incubated in the presence of 10% seminal plasma compared to 0, 25, 50, or 100% seminal plasma (P < 0.001). The mean ± SEM percentage of epididymal sperm with intact acrosomes was less (P < 0.001) in samples incubated in 0% seminal plasma (39.4 ± 3.73) compared to 10% (75.3 ± 1.20) or 100% (77.4 ± 0.90) within 1 h after incubation. However, DNA integrity of ejaculated and epididymal sperm was not significantly affected by seminal plasma concentration. The mean viability of ejaculated sperm was reduced in the presence of 100 (12.7 ± 2.33) compared to 10% (36.2 ± 4.68) seminal plasma (P < 0.001) within 1 h of incubation. We concluded that alpaca semen should be diluted to a final concentration of 10% seminal plasma to prolong motility, preserve acrosome integrity, and maintain viability of sperm.     

Relationship of seminal plasma level and extender type to sperm motility and DNA integrity

The relationship between seminal plasma level (0, 10, or 20%) and extender type [Kenney type (EZ-Mixin-CST) or Kenney-modified Tyrodes-KMT] to the susceptibility of sperm DNA to denaturation and sperm motility measures were investigated in cooled (5 degrees C) stallion sperm. Three ejaculates from each of three fertile stallions were collected in an artificial vagina and processed as follows: diluted one part uncentrifuged semen with four parts of extender to a final concentration of 20% seminal plasma in either CST or KMT (20% CST; 20% KMT); diluted to a final concentration of 25 million sperm/mL in either CST or KMT (10% CST; 10% KMT); centrifuged to remove virtually all seminal plasma and resuspended in either CST or KMT (0% CST-Cent; 0% KMT-Cent); centrifuged semen to remove virtually all seminal plasma and resuspended with previously filtered seminal plasma from the same stallion in either CST or KMT to a final concentration of 20% seminal plasma (20% CST-Cent; 20% KMT-Cent). Sperm motion characteristics were determined by CASA and DNA integrity (%COMP, percent of cells outside the main population) evaluated by the Sperm Chromatin Structure Assay prior to cooling, and after 24 and 48 h cooled-storage at 5 degrees C. After 48 h of storage at 5 degrees C, extenders with 0% seminal plasma (0% CST-Cent, 0% KMT-Cent) maintained highest quality DNA (P < 0.05), but 0% KMT-Cent maintained higher velocity measures (P < 0.05) than 0% CST-Cent. Total sperm motility was highest (P < 0.05) in 0% CST-Cent, 0% KMT-Cent, 10% CST, 20% CST-Cent, and 20% CST compared to the other treatment groups. Progressive sperm motility was highest (P < 0.05) after 48 h of storage in the treatment with 10% seminal plasma in Kenney extender (10% CST), despite a reduction in DNA integrity. Regardless of extender type, addition of 20% seminal plasma following centrifugation resulted in almost a two-fold increase in %COMP(alpha t), even though one of the treatments (20% CST-Cent) maintained total and progressive motility similar to treatments with no seminal plasma, suggesting that sperm motility and DNA integrity may respond independently to environmental conditions. Overall, better quality sperm features (motility and DNA) were maintained in sperm from which seminal plasma was removed followed by resuspension in either Kenney extender or modified Kenney Tyrodes-type extender.     

Antioxidant capacity of seminal plasma measured by TAS Randox

BACKGROUND: An imbalance between reactive oxygen species (ROS) generation in sperm and antioxidant capacity of seminal plasma has been linked to male infertility. The antioxidant power of biological fluids can be evaluated either by measurement of individual antioxidants or total antioxidant capacity (TAC). The aim of this study was to assess whether TAS Randox can also be used for seminal plasma antioxidant capacity estimation. MATERIAL AND METHODS: Freshly thawed aliquots of seminal plasma and blood serum of 38 males from infertile couples and 24 healthy normospermic controls were simultaneously assayed using TAS Randox reagents on the Hitachi Modular P800 Analyzer. Semen analysis was performed according to WHO guidelines. ROS in fresh sperm suspension in phosphate buffered saline was measured by chemiluminescence immediately after separation of seminal plasma. RESULTS: Semen analysis showed that in our study group only 14 males were normospermic and 24 males had mostly combined pathologies. The medians for ROS production were similar in both the study and the control groups (4850 and 5450 RLU/min, resp). Seminal plasma TAS levels were significantly lower (p<0.02) in the study group while blood serum TAS levels were similar in both groups. A significant positive correlation (p<0.05) between TAS in seminal plasma and serum was found, seminal plasma levels being on average 1.4 times higher. CONCLUSIONS: The TAS Randox kit may be used for clinical studies intended to identify decreased antioxidant power in the seminal fluid of infertile men.     

Chemical composition of seminal and ovarian fluids of chinook salmon (Oncorhynchus tshawytscha) and their effects on sperm motility traits

The relationships between the compositions of ovarian, seminal fluids and sperm function are not well known in teleostean fish species. The objective of the present study was to determine the concentration of the major inorganic ions (Na(+), K(+), Ca(2+), Mg, Cl(-)), osmolality, and pH of ovarian and seminal fluid of sexually mature chinook salmon (Oncorhynchus tshawytscha), and to determine if the composition of these fluids influences sperm motility traits (swimming speed, duration of forward mobility, swimming path trajectory, and percent motility). Cation concentrations and osmolality were significantly different in the two fluids. The ionic composition of ovarian fluid differed among individual females, and also among samples collected at different times through the spawning season. Carbonate and bicarbonate were the principal buffer ions in ovarian fluid, and its viscosity was considerably greater than that of water and was shear-dependent. The duration of forward motility (longevity) of spermatozoa, swimming speed, percent motility, and path trajectory were measured using milt from 10 males activated in the ovarian fluid from 7 females whose ion concentrations were known. No significant correlations were observed between the composition of the seminal fluid and sperm traits. However, in ovarian fluid, sperm longevity was negatively correlated with variation in [Ca(2+)] and [Mg(2+)], while percent motility increased with increasing [Mg(2+)]. These observations provide a possible chemical basis for cryptic female mate choice whereby female ovarian fluid differentially influences the behaviour of sperm from different males, and thus their fertilization success.     

Evaluation of superoxide dismutase activity and its impact on semen quality parameters of infertile men

The evaluation of superoxide dismutase (SOD) activity, as one of the most important antioxidative defence enzymes, in seminal plasma of patients consulting for male infertility was presented in the article. The study included also the determination of its influence on selected human semen quality parameters. The material represents semen samples obtained from 15 men, which were divided into two groups: Group I (n=10) including patients consulting for infertility and Group II (n=5) containing healthy sperm donors as a control. All of the semen samples were cryopreserved and stored in liquid nitrogen. The frozen samples were thawed at the same time and then SOD activity was determined spectrophotometrically. The analysis of the investigations results indicates a significantly lower semen SOD activity detected in oligoasthenozoospermic patients, comparing to the activity found in normospermic men. The study showed a positive correlation between SOD activity in seminal plasma and semen quality parameters--sperm concentration and overall motility, which are regarded as the most important for normal fertilizing ability of the spermatozoa. Significantly lower SOD activity in seminal plasma of infertile patients, comparing to healthy sperm donors, as well as positive correlation and beneficial impact of SOD activity on human semen quality parameters seem to confirm the observations, that decreased seminal plasma scavenger antioxidant capacity, particularly in form of low SOD activity, can be responsible for male infertility. This trial shows that SOD activity survey in seminal plasma could be a useful tool for determining sperm fertilization potential and could improve the diagnosis of male infertility.     

The maintenance of motility and the surface properties of epididymal spermatozoa from bull, rabbit and ram in homologous seminal and epididymal plasma.

Epididymal spermatozoa from bull, rabbit and ram were incubated in homologous epididymal plasma or seminal plasma in a buffered saline-based medium with or without serum albumin. The spermatozoa were either diluted directly into the medium or were washed first. No effect of washing was observed on the subsequent reaction of the cells to the different media. A considerable proportion of the populations of epididymal spermatozoa survived (i.e. continued to exhibit motility) for up to 22 h at 30 degrees C in the simple saline-based medium. Initially epididymal plasma had a slight stimulatory effect on sperm motility in ram and bull but it had no effect on sperm survival in any of the 3 species. Seminal plasma stimulated motility markedly in ram initially, but in all 3 species seminal plasma was detrimental to survival: in ram even a 15-min exposure to the fluid reduced survival. Serum albumin also stimulated motility; it delayed, but did not prevent, the detrimental effect of seminal plasma, although it had no effect itself on survival. The effects of epididymal plasma, seminal plasma and serum albumin on surface properties of epididymal spermatozoa, i.e. agglutination, sticking-to-glass and eosinophilia, were also noted. These varied between species and there was no correlation between these effects and the effects on motility and survival.     

Hofmeister effect underlying the quiescence of sperm motility in the vas deferens of the viviparous guppy Poecilia reticulata

Guppy sperm are immotile in the fluid (seminal plasma) of the vas deferens. We previously reported that the initiation of sperm motility is regulated by "Hofmeister solutes" in the isotonic medium. This indicates that chaotropes in solution activate the guppy sperm, whereas counteracting kosmotropes negate this activational effect and keep the sperm immotile. Here we show that seminal plasma has a strong inhibitory effect on sperm activation in response to chaotropes and multivalent ions, and that this inhibitory effect is due to kosmotropicity of the seminal plasma. These findings suggest a novel system of regulation of sperm motility in the guppy, a viviparious fish, in which the sperm are kept immotile in the vas deferens by a physicochemical effect (the Hofmeister effect) of the seminal plasma.     

Olive oil supplemented with Coenzyme Q(10): effect on plasma and lipoprotein oxidative status

Olive oil consumption is associated with protective cardiovascular properties, including some beneficial modifications in lipoprotein profile and composition. Coenzyme Q(10) (CoQ(10)) exerts a protective effect on plasma lipoproteins. Aim of the study was to investigate whether extra virgin (EV) olive oil enriched with CoQ(10) affects CoQ(10) levels and oxidative status in plasma and in isolated lipoproteins. Twelve subjects were administered 20 mL olive oil per day for 2 weeks, followed by 2 weeks of olive oil enriched with 20 mg and 2 more weeks with 40 mg of CoQ(10). Plasma and isolated lipoproteins were collected in each phase of the study and subsequently analyzed to assess lipid profile, CoQ10 levels, ORAC assay, resistance of lipoproteins to peroxidation and paroxonase 1 activity. Plasma CoQ(10) levels significantly increased with the 20 mg (+73%) and 40 mg dose (+170%), while the percentage of oxidized CoQ(10) decreased. A significant inverse correlation was found in plasma between percentage of oxidized CoQ(10) and total antioxidant capacity. A lower susceptibility of LDL to peroxidation was also found. Finally, a positive correlation was observed between concentration of CoQ(10) in HDL and paraoxonase-1 activity. EV olive oil enriched with both doses of CoQ(10) significantly affects its bioavailability and plasma redox status. These changes are associated with a decreased susceptibility of plasma lipoproteins to peroxidation associated with a chain-breaking antioxidant activity of the formulation.     

Sperm motility in fishes. (II) Effects of ions and osmolality: a review

The spermatozoa of most fish species are immotile in the testis and seminal plasma. Therefore, motility is induced after the spermatozoa are released into the aqueous environment during natural reproduction or into the diluent during artificial reproduction. There are clear relationships between seminal plasma composition and osmolality and the duration of fish sperm motility. Various parameters such as ion concentrations (K+, Na+, and Ca2+), osmotic pressure, pH, temperature and dilution rate affect motility. In the present paper, we review the roles of these ions on sperm motility in Salmonidae, Cyprinidae, Acipenseridae and marine fishes, and their relationship with seminal plasma composition. Results in the literature show that: 1. K+ is a key ion controlling sperm motility in Salmonidae and Acipenseridae in combination with osmotic pressure; this control is more simple in other fish species: sperm motility is prevented when the osmotic pressure is high (Cyprinidae) or low (marine fishes) compared to that of the seminal fluid. 2. Cations (mostly divalent, such as Ca2+) are antagonistic with the inhibitory effect of K+ on sperm motility. 3. In many species, Ca2+ influx and K+ or Na+ efflux through specific ionic channels change the membrane potential and eventually lead to an increase in cAMP concentration in the cell, which constitutes the initiation signal for sperm motility in Salmonidae. 4. Media that are hyper- and hypo-osmotic relative to seminal fluid trigger sperm motility in marine and freshwater fishes, respectively. 5. The motility of fish spermatozoa is controlled through their sensitivity to osmolality and ion concentrations. This phenomenon is related to ionic channel activities in the membrane and governs the motility mechanisms of axonemes.     

The effects of radiation on sperm swimming behavior depend on plasma oxidative status in the barn swallow (Hirundo rustica)

Sperm are highly susceptible to reactive oxygen species (ROS) that can damage sperm DNA and structure, resulting in reduced fertilizing capacity. Exposure to radioactive contamination can also impair sperm swimming behavior and fertilizing ability, both through a reduction of sperm DNA integrity and via an increased generation of reactive oxygen species (ROS). However, the relationship between individual oxidative status and sperm swimming behavior has never been investigated in any wild population of animals exposed to radioactive contamination. We studied the motility of sperm collected from barn swallows, Hirundo rustica, breeding under different levels of radioactive contamination following the Chernobyl accident in 1986, in relation to individual oxidative status. We tested the hypothesis that the degree of impairment of sperm swimming behavior by radioactive contamination depended on plasma antioxidant capacity, the level of reactive oxygen metabolites (ROMs) and oxidative stress (sensu Costantini et al. 2006), a better oxidative status being associated with higher sperm motility. Sperm behavior parameters were subjected to principal component (PC) analysis, which extracted four PCs explaining 86% of the variance in sperm motility. PC2, representing sperm with high track velocity and ample lateral head displacement, was significantly predicted by the interaction between radiation level and either oxidative damage or oxidative stress. Contrary to our predictions, the highest values of PC2 were associated with relatively high radiation levels, particularly for high levels of either ROMs or oxidative stress. In addition, there was a tendency for values of PC3 (representing the percent of motile sperm) and PC4 (representing slow sperm with high beat cross frequency) to depend on the interaction between radiation level and total plasma antioxidant protection. Our results confirm the importance of oxidative status in determining the genetic and physiological outcome of exposure to radioactive contamination, complementing previous studies relating sperm abnormality to circulating levels of specific antioxidants. Our results also complement previous evidence that oxidative damage of sperm was negatively related to sperm motility, thus indicating a possible trade-off in quenching pro-oxidant compounds in the plasma and the seminal fluid.