PubMed HealthSearch

Biomedical subjects

D Feneux

Publications and source records attributed to D Feneux.

17 recordsLinked to original sources

Effect of sperm-associated antibodies on the dynamics of sperm movement and on the acrosome reaction of human spermatozoa.

Anti-sperm antibodies were eluted from the sperm cell fraction of autoimmune human ejaculates and transferred onto normal motile spermatozoa. The movement and the acrosomal status of these antibody-coated spermatozoa were evaluated after incubation in a capacitating medium. The amplitude of lateral head displacement (ALH) and the straight line velocity (VSL) were analyzed using an HTM automated motility analyser. Acrosomal loss was monitored by an FITC-conjugated lectin binding technique. During the 6-h incubation in BWW-BSA medium, antibody-free and antibody-coated spermatozoa exhibited significant changes of ALH and VSL distribution that evolved differently in the two populations. The dynamics of sperm movement in control spermatozoa were apparently modified by the presence of antibodies on the sperm membrane. The low percentage of spontaneous acrosomal loss obtained in control populations, even after 20 h of incubation, was not modified by the presence of antibodies on spermatozoa. However, the same antibodies decreased the acrosomal loss induced by a calcium ionophore after 3 h of incubation in capacitating conditions. These results suggest that sperm capacitation and acrosome reaction, considered as essential for successful fertilization, can be altered by antisperm antibodies present on human ejaculated spermatozoa.

Acrosome

Decrease of internal free calcium and human sperm movement.

In order to elucidate the effects of calcium on the movement of human spermatozoa, studies were conducted using motile cells selected by swim-up migration at 37 degrees C in 5% CO2 in air in a synthetic BWW medium containing 1.7 x 10(-3) M CaCl2 or BWW without added calcium (BWW-Ca). Preliminary experiments have confirmed that the addition of EGTA (5 x 10(-3); 10(-2) M) to BWW medium decreased the intracellular calcium concentration ((Ca++)i) of spermatozoa, as measured in cells loaded with a fluorescent Ca++ indicator, Quin-2. Concomitant measurements of (Ca++)i and sperm movement (analysed by videomicrography at 200 f/s at room temperature) were carried out on Quin-2 loaded cells incubated in BWW-Ca medium plus EGTA (10(-5) M; 10(-4) M; 10(-3) M). Under these conditions a decrease in (Ca++)i was observed and associated with a decrease in mean amplitude of lateral head displacement (ALH). Analysis using an automatic analyser (Hamilton Thorn at 37 degrees C) confirmed these results: the percentage of spermatozoa swimming with ALH greater than or equal to 6 microns is decreased when the external free calcium in BWW-Ca is decreased by the addition of 10(-5) M, 10(-4) M, or 10(-3) M EGTA. Flagellar analysis of the sperm population characterized by ALH greater than or equal to 6 microns showed a large proximal curvature of the tail associated with a low propagation wave velocity and a low beat frequency as compared to the spermatozoa with ALH less than 6 microns with similar progressive velocities. These characteristics result in a high flagellar beat efficiency (in terms of head displacement per beat). The disappearance of this pattern of movement when intracellular calcium is lowered indicates that calcium plays a complex role in the relationship between curvature and wave propagation. The ability of spermatozoa to modulate their movement in response to an alteration in the intracellular calcium level confirms the role of calcium in controlling flagellar movement in intact cells.

Aminoquinolines

Comparative kinetics of short and long sperm in sperm dimorphic Drosophila species.

All species of the Drosophila obscura group exhibit within-ejaculate sperm length dimorphism. The present work is a contribution to the understanding of sperm competition through a comparative study of sperm kinetic parameters in four of these species. Videomicrographic observations at 200 frames per second of sperm from males and females, out of the storage organ, prior or after storage were made. Drosophila sperm display both major and minor waves. The former is analysed by measuring coiling diameter (micron) and the latter by recording both beat frequency (s-1) and wave propagation velocity (micron.s-1). Results show that the 'behaviour' of short and long spermatozoa noticeably differ: short sperm kinetics remains unaltered after storage while both major and minor waves of long spermatozoa are markedly modified. Thus, evidence is provided here of a sort of "differential activation" which is assumed to result in different survival abilities of short and long sperm within the storage organ of females.

Animals

Effects of pH on the reactivation of human spermatozoa demembranated with Triton X-100.

The aim of this work was to study the role of different parameters involved in the motility of human spermatozoa. Human spermatozoa were totally demembranated with 0.05% Triton X-100, and the demembranation was checked using electron microscopy. We have shown that, with a concentration of ATP-Mg lower than 2 mM, a pH effect was observed with a dose-dependent motility reactivation at pH 7.1, with 14% +/- 2.0% motile cells at 1 mM ATP-Mg and a straight line velocity (VSL) of 12.0 +/- 1.4 microns/sec. However, at pH 7.8, more than 65% of the spermatozoa were reactivated with as low as 0.02 mM ATP-Mg and 77.8% +/- 2.5% of them were motile at 1 mM ATP-Mg and had a VSL of 23.4 +/- 3.9 microns/sec. The depletion of free calcium by the addition of 0.5 mM EGTA in the reactivation medium (RM) improved the percentage of motile cells and the VSL most markedly at low ATP-Mg and low pH. If no MgSO4 was added in RM, cells were not motile at pH 7.8, but 30-40% reactivated at pH 7.1. If 5 mM Ca2+ was added to the RM, up to 88% of the cells became reactivated at both pHs, but the beat frequencies were very low, suggesting different mechanisms of reactivation when Mg2+ or when Ca2+ is present in the RM.

Adenosine Triphosphate

In-vitro effects of anti-sperm antibodies on human sperm movement.

The present study was designed to investigate whether autoantibodies to external domains of the sperm plasma membrane affect the movement of normal motile spermatozoa. Eight sera and 20 seminal plasma samples containing high levels of anti-sperm antibodies as well as antibodies eluted from the sperm fraction of 19 autoimmune ejaculates were incubated with donor's motile spermatozoa, obtained by swim-up migration in Tyrode's solution. Sperm movement was analysed using 1 s exposure microphotography when greater than 70% of the spermatozoa were coated with antibodies (after 30-90 min of incubation). At least 50 tracks of progressively motile spermatozoa were analysed in order to obtain the mean values of the amplitude of lateral head displacement (ALH) and the velocity of progression (VSL). Serum antibodies and sperm eluted antibodies had quite consistent but opposite effects on sperm movement; serum antibodies increased ALH and decreased VSL whereas eluted antibodies decreased ALH and increased VSL. Seminal antibodies did not affect these two parameters significantly. Furthermore, seminal antibodies and sperm eluted antibodies obtained from the same ejaculates had distinct effects on ALH and/or VSL. This diversity was apparently not linked to antibody isotype or localization on the sperm membrane; it might be due to differences in the composition of the extracellular media. These results suggest a dynamic effect of anti-sperm antibodies on sperm movement, a possibility that merits further investigation.

Autoantibodies

Motion of individual human spermatozoa, both normal and lacking the outer dynein arms, during a continuous temperature rise.

The effect of increasing temperature from 22-25 degrees C to 37 degrees C on various motion characteristics of individual normal human spermatozoa and spermatozoa lacking the outer dynein arms (LODA) was studied by using a new automatic microscopic tracking method. It was found that: 1) The curvilinear velocity (Vc, measured between 1-3 sec) of both normal and LODA spermatozoa, fluctuated more or less intensely between spermatozoa; this fluctuation was not thermodependent. 2) The average Vc in the two groups of spermatozoa increased with the rise in temperature at a similar rate (1 micron/sec/degrees C), but LODA spermatozoa had an initial Vc lower than that of normal spermatozoa (12.5 +/- 5.3 microns/sec and 34.2 +/- 8.2 microns/sec, respectively). 3) The profile of the Vc increase associated with the temperature rise was different for the two groups of spermatozoa: for LODA spermatozoa it was linear between 25-37 degrees C, whereas for normal spermatozoa a plateau was reached at about 31 degrees C. 4) Various patterns of trajectory were found for both normal and LODA spermatozoa; these patterns were unrelated to temperature. However, LODA spermatozoa had more linear trajectories than normal spermatozoa. 5) Plots derived from reaction rate theory showed that the activation enthalpy, delta H was a function of the increase of Vc for both normal and LODA spermatozoa, but that delta H was higher for LODA spermatozoa.

Adenosine Triphosphatases

[The role of Chlamydia trachomatis in producing abnormal movements by spermatozoa].

The authors analysed 100 sperm samples from asymptomatic patients and compared them with a control series of sperm donors who had been considered fertile by CECOS of Marseille or from men whose partners had conceived. They found Chlamydia trachomatis in 29% of the cases studied (P less than 0.0001). They found an abnormal movement of the sperm which they called the "Jerk Phenomenon" and which was found in 76% of cases (P less than 0.0001), where the culture for Chlamydia trachomatis was positive. This correlation does not change in association with other germs. Micro-cinematographic studies confirm the asthenospermic character of this movement. Since the sperm movements become normal after treatment with tetracycline one must consider that Chlamydia trachomatis can be an etiological agent for infertility in men.

Adult

Male factors and the likelihood of pregnancy in infertile couples. I. Study of sperm characteristics.

A prospective study of 394 infertile men was conducted over 3 years following a primary semen analysis. The cumulative pregnancy rate was 43 and 64% after 1 and 3 years, respectively. The pregnancy rate was significantly higher in the secondary infertile group. The study of various sperm factors and the occurrence of pregnancy showed that they were not of equal significance in predicting male fertility potential. The percentage of pregnancies decreased significantly only when the sperm concentration was less than 5 x 10(6)/ml. The pregnancy rate increased significantly with the percentage of motile sperm. The percentage of sperm with normal morphology was also found to be significantly higher when a pregnancy occurred than when the couple remained infertile (43.6% vs 37.7%). In a detailed morphological analysis of the sperm, six abnormalities (microcephaly, double head, amorphous head, cytoplasmic droplet, bent tail and coiled tail) were found to be significantly more frequent when a pregnancy did not occur. The most predictive value was given by the Multiple Anomalies Index (MAI), which is the mean number of abnormalities observed per abnormal sperm. The pregnancy rate was significantly lower after both 1 and 3 years when the MAI was greater than 1.6. Multivariate analysis showed that the best prognostic indicator of fertility was given by the percentage of motile sperm and the MAI, particularly in patients with primary infertility.

Female

Male factors and the likelihood of pregnancy in infertile couples. II. Study of clinical characteristics--practical consequences.

A prospective study of 394 infertile men was conducted over 3 years following a primary semen analysis. Simple comparisons between the groups of men whose partners conceived and those that did not, showed that the mean duration of infertility in the primary infertile group was significantly shorter when a pregnancy was observed, while age differed significantly between the two populations in the secondary infertile group. Multivariate analyses, taking these variables and sperm characteristics into account, showed that prognostic variables for the occurrence of pregnancy were the duration of infertility, sperm motility and the multiple anomalies index in the primary infertile group, and age of the male partner and percentage of normal sperm in the secondary infertile group. Tables for estimating the probability of observing a pregnancy as a function of these criteria are presented. In this study no positive influence of treatment on the occurrence of a pregnancy was found during the 3 years following the first semen analysis.

Age Factors

[In vivo and in vitro fertilizing ability of immature human epididymal spermatozoa].

In cases of congenital absence of vas deferens (9 patients) or after failure of previous epididymovasostomy (2 patients), in vitro fertilization (IVF) was attempted with spermatozoa surgically obtained at the epididymal caput level. These sperm populations showed little progressive motility (5.9 +/- 6.5%) and an marked necrozoospermia (19.3 +/- 17.4%). Stimulation by caffeine (4.5 mM) alone or associated with heterologue normal seminal fluid resulted in most of the cases in an initiation of motility with an improvement of the progressive velocity. In 9 IVF attempts, 31 mature oocytes were inseminated with 5.10(3) to 1.5.10(6) motile spermatozoa. The dynamic characteristics in 3 inseminated sperm populations were Vp (24.2 +/- 8.3 microns/s), Ah (8.6 +/- 2.0 microns) at room temperature. Sperm binding to zona pellucida was decreased (0 to about 20 spermatozoa per oocyte) and there was no fertilization. In the same period, 21 attempts of intra uterine insemination and 14 attempts of intracervical inseminations were made in 5 couples who remained infertile after patent high epididymovasostomy (4) or vasovasostomy (1) and having immature spermatozoa stimulated as previously described. Antisperm antibodies were detected on the ejaculated spermatozoa in four men. No pregnancy was obtained with these immature stimulated spermatozoa. The fertility of the female partners was confirmed in 3 women after insemination with donor sperm.

Adult

Sperm analysis.

Human semen analysis is the first biological step of male fertility assessment. Its performance requires the use of standardized and objective procedures. The results of the tests may allow to conclude to a man's sterility when they reveal e.g. an azoospermia or an alteration of sperm morphology or motility incompatible with fertilization. More often however, it is difficult to precisely determine the relationships between the observed sperm anomalies and infertility. In a follow-up study of 520 infertile men over 3 years, the pregnancy rate was found to be significantly lower only in the cases where sperm concentration values were less than 5.10(6)/ml and unchanged for concentrations above this value. No threshold values were found for sperm motility and morphology, although the chances of conception were closely related to these two parameters for sperm concentration values above 5.10(6)/ml. Various tests have been described to evaluate the human sperm ability to migrate through the female genital tract and fertilize the oocyte. These tests and the human in vitro fertilization assay allow a better understanding of the structural and dynamical parameters mostly involved in sperm function.

Fertilization in Vitro

Abnormal distribution of the periaxonemal structures in a human sperm flagellar dyskinesia.

The spermatozoa from four infertile patients showing a flagellar dyskinesia due to abnormal flagellar wave development have been studied by light and transmission electron microscopy (TEM) for flagellar morphology. No axonemal anomalies were found but modification of the periaxonemal structures was observed. The results of a stereological analysis revealed abnormal extension of the individual dense fibres along the axoneme in the four cases as compared with a control group. The order of termination of those structures was therefore altered. However, the overall fibre extension was the same in both groups (ie, 60% of the principal piece). The number and the location of the longitudinal columns were also modified, the predominant anomaly being the presence of a single column. The possible influence of those structural anomalies on the pattern of sperm movement is discussed. Our observations seem to agree with a previous hypothesis of the literature, that the dense fibres might play a role in flagellar flexibility. More particularly, we suggest that the abnormal extension of dense fibres No. 2, 3, and 4 and the symmetric distribution of the dense fibres on both sides of the plane of beating may alter the flagellar curvature amplitude and the cell rotation frequency.

Actin Cytoskeleton

Sperm factors related to failure of human in-vitro fertilization.

Two groups of men were retrospectively selected according to their observed success in in-vitro fertilization. Seminal and post-migration sperm samples from a low fertilization rate group (less than or equal to 33% cleaved embryos) have been compared to results obtained from a high fertilization rate group (greater than or equal to 66%). It was found that a low mean value of the amplitude of lateral sperm head displacement and an increased percentage of abnormal acrosomes were related to in-vitro fertilization failure. None of the individual sperm factors studied was found to determine in-vitro fertilization success with certainty; only when they were considered in combination was it possible to predict the likelihood of successful in-vitro fertilization of human oocytes.

Acrosome

Steroid therapy for male infertility associated with antisperm antibodies. Results of a small randomized clinical trial.

Ten infertile men with significant titres of antisperm antibodies were entered into a randomized double-blind study to test the efficacy of corticosteroid therapy compared to a placebo. Prednisolone was given orally at a dose of 1 mg/kg/day for 9 days repeated over 3 cycles (their wives' menstrual cycles). This treatment had no significant effect, when compared to placebo, on fertility, serum antibody levels or semen characteristics. A slight decrease in the titre of seminal antibodies was, however, observed in patients receiving prednisolone. In individuals, there were important fluctuations in antibody levels which were independent of drug administration.

Adult

Sliding spermatozoa: a dyskinesia responsible for human infertility?

Microcinematographic analysis at 50 frames/second of motile spermatozoa from four sterile men, which were permanently unable to penetrate the cervical mucus or migrate through it was performed at ambient temperature. In all cases, we found the same abnormal pattern of movement, characterized by a very small amplitude of the periodic lateral displacement of the head and abnormal displacement of the wave along the flagellum. The results assessed the importance of normal sperm flagellar dynamics for fertility.

Cervix Mucus