Shubhadeep Roychoudhury

In vitro study on the effects of lead and mercury on porcine ovarian granulosa cells

The heavy metals lead (Pb) and mercury (Hg) pose potential risks to sustainability of environment and thus to our future generations. General objective of this in vitro study was to examine the secretory activity of porcine ovarian granulosa cells after Pb and Hg administration and to outline the potential intracellular mediators of its effects. For this purpose, release of insulin-like growth factor I (IGF–I) and steroid hormone progesterone (P4), expression of proliferation- related (cyclin B1) and apoptosis-related (caspase-3) peptides was examined in porcine ovarian granulosa cells after heavy metals administration. Obtained data indicate Pb–induced inhibition of IGF–I release at lower doses (0.063 mg/mL and 0.046 mg/mL) by ovarian granulosa cells. However, P4 release was not influenced by Pb addition, while the expression of cyclin B1 and caspase-3 was induced by Pb addition. These results indicate that Pb can affect the pathway of proliferation and apoptosis of porcine ovarian granulosa cells through intracellular substances such as cyclin B1 and caspase–3. On the other hand, the P4 release by ovarian granulosa cells of pregnant gilts was stimulated by experimental Pb administration at doses of 0.25 mg/mL and 0.063 mg/mL and experimental Hg administration at doses 0.25 mg/mL and 0.083 mg/mL. P4 release by ovarian cells of pregnant gilts was not influenced by a combinatory dose of FSH (1.0 ng/mL) + Pb (0.083 mg/mL) + Hg (0.083 mg/mL) but it was inhibited by experimental administration of FSH (10 ng/mL) + Pb (0.25 ng/mL) + Hg (0.25 ng/mL). Possible involvement of heavy metals – Pb and Hg and pituitary hormone FSH, in the regulation of P4 release by porcine ovarian granulosa cells of pregnant gilts was noted. Data obtained from in vitro studies suggest the dose dependent association of heavy metals administration with the hormonal release by porcine ovarian granulosa cells. This association also depended on pregnancy of the gilts.

Influence of a 50 Hz extra low frequency electromagnetic field on spermatozoa motility and fertilization rates in rabbits

Effects of a 50 Hz extra-low frequency electromagnetic field (ELF EMF) on in vitro rabbit spermatozoa motility were analyzed, as well as the effect on fertilization rates after insemination. Pooled semen samples and a control were exposed to 50 Hz ELF EMF. The difference of the samples of the test groups G1 and G2 with the control group CG (75.56%) for spermatozoa motility were found to be significant (P < 0.01). Differences were significant (P < 0.01) for curvilinear velocity (VCL) between the test group G3 (122.38 μ m/s) and the control group CG (112.02 μ m/s). Hormonally stimulated adult (9–12 months) females (n = 140) were inseminated with semen samples from G1, G2, G3 and CG (0.88 × 109 spermatozoa/0.5 mL average insemination portion) immediately after ELF EMF exposure and fertilization (kindling) rates were calculated. For the G2 it was 54.28% data indicate 50 Hz ELF EMF induced alterations of spermatozoa motility and kindling rate in rabbits, therefore influencing fertility.

In vitro copper inhibition of the rabbit spermatozoa motility.

Copper is an essential trace element that is strongly bioaccumulated. In this study the effects of this environmental contaminant on various spermatozoa motility parameters in vitro was analyzed. Rabbit spermatozoa were cultured with copper (CuSO4.5H2O) which was added to semen in 5% solution and subsequently diluted 1:1–10. Analysis was carried out using a Computer Assisted Semen Analyzer (CASA) system in 3 time periods (0, 60 and 120 minutes). At Time 0, the highest motility in control group was detected. Motility in groups with copper administration was significantly (P < 0.05) decreased to 8.25–19.37%. The decrease of progressive motility was even more significant—in control 73.37 ± 7.01% and in experimental groups up to 0%. At Time 60, motility significantly (P < 0.05) decreased from 59.62 ± 11.40% to 7.50 ± 3.66%. Progressive motility decreased from 49.62 ± 16.10% to 0% in the group with the highest copper concentration. After 120 minutes of incubation the motility was 57.75 ± 5.82% in control group and in all experimental groups it significantly (P < 0.05) decreased to 8.75%. Detailed evaluation of spermatozoa distance (DCL – distance curved line; DAP – distance average path; DSL – distance straight line) and velocity (VCL – velocity curved line; VAP – velocity average path; VSL – velocity straight line) parameters detected significant (P < 0.05) decrease in all studied markers in groups with copper addition in comparison with control group at all time periods. Straightness, linearity, wobble, amplitude of lateral head displacement and beat cross-frequency of spermatozoa were altered weakly. Detected data clearly confirm negative effects of high copper concentrations in semen on spermatozoa motility parameters and subsequent reproductive alteration in male sexual functions.

Bibliometrics: tracking research impact by selecting the appropriate metrics

Traditionally, the success of a researcher is assessed by the number of publications he or she publishes in peer-reviewed, indexed, high impact journals. This essential yardstick, often referred to as the impact of a specific researcher, is assessed through the use of various metrics. While researchers may be acquainted with such matrices, many do not know how to use them to enhance their careers. In addition to these metrics, a number of other factors should be taken into consideration to objectively evaluate a scientist′s profile as a researcher and academician. Moreover, each metric has its own limitations that need to be considered when selecting an appropriate metric for evaluation. This paper provides a broad overview of the wide array of metrics currently in use in academia and research. Popular metrics are discussed and defined, including traditional metrics and article-level metrics, some of which are applied to researchers for a greater understanding of a particular concept, including varicocele that is the thematic area of this Special Issue of Asian Journal of Andrology. We recommend the combined use of quantitative and qualitative evaluation using judiciously selected metrics for a more objective assessment of scholarly output and research impact.

Oxidation-reduction potential of semen: what is its role in the treatment of male infertility?

The diagnosis of male infertility relies largely on conventional semen analysis, and its interpretation has a profound influence on subsequent management of patients. Despite poor correlation between conventional semen parameters and male fertility potential, inclusion of advanced semen quality tests to routine male infertility workup algorithms has not been widely accepted. Oxidative stress is one of the major mediators in various etiologies of male infertility; it has deleterious effects on spermatozoa, including DNA damage. Alleviation of oxidative stress constitutes a potential treatment strategy for male infertility. Measurement of seminal oxidative stress is of crucial role in the identification and monitoring of patients who may benefit from treatments. Various tests including reactive oxygen species (ROS) assay, total antioxidant capacity (TAC) assay or malondialdehyde (MDA) assay used by different laboratories have their own drawbacks. Oxidation-reduction potential (ORP) is a measure of overall balance between oxidants and antioxidants, providing a comprehensive measure of oxidative stress. The MiOXSYS™ System is a novel technology based on a galvanostatic measure of electrons; it presents static ORP (sORP) measures with static referring to the passive or current state of activity between oxidants and antioxidants. Preliminary studies have correlated sORP to poor semen qualities. It is potentially useful in prognostication of assisted reproductive techniques outcomes, screening of antioxidants either in vivo or during IVF cycles, identification of infertile men who may benefit from treatment of oxidative stress, and monitoring of treatment success. The simplified laboratory test requiring a small amount of semen would facilitate clinical application and research in the field. In this paper, we discuss the measurement of ORP by the MiOXSYS System as a real-time assessment of seminal oxidative stress, and argue that it is a potential valuable clinical test that should be incorporated into the male infertility workup and become an important guide to the treatment of oxidative stress-induced male infertility.

In vitro copper toxicity on rabbit spermatozoa motility, morphology and cell membrane integrity

In this in vitro study the effects of copper sulphate on the motility, morphology and structural integrity of rabbit spermatozoa were investigated. The spermatozoa motility was evaluated by CASA method and Annexin analysis was used for detection of structural changes. For analysis of morphology samples of rabbit semen were fixed with Hancocks solution and stained with Giemsa, and for each sample at least 500 spermatozoa were evaluated. The concentration of copper in the medium varied from 3.57 to 4.85 μg CuSO4/mL. At Time 0 the highest motility was detected in the control group (57.78 ± 3.90%). Motility in groups with copper administration was lower in comparison to control. Significant differences were detected in groups with 3.70–4.85 μg CuSO4/mL (P<0.05) at Time 0. After 1 h of incubation with copper sulphate the motility significantly decreased almost in all experimental groups. However, at Time 2 h significant increase of total motility was observed in groups with lower concentrations of copper (3.57 and 3.63 μg CuSO4/mL). After 24 and 48 h of incubation almost all the spermatozoa were dead recording no motility at all concentrations. The concentration- dependent decrease of spermatozoa motility up to 50% of control was detected for the group receiving highest copper administration (4.85 μg CuSO4/mL) at Times 1 and 2 h. Progressive motility had an identical trend to that of motility in all experimental groups, at all culture times and for all concentrations. Evaluation of distance and velocity parameters indicated that a sort of stress tolerance developed in lower concentrations (3.57 and 3.63 μg CuSO4/mL). At lower concentrations, an increase was noted for distance parameter DCL and velocity parameter VCL, indirectly confirming the significant motility and progressive motility increase. Other motility parameters (straightness index, linearity index, wobble and amplitude of lateral head displacement) revealed decrease in the group with the highest copper concentration (4.85 μg CuSO4/mL) in comparison to the control group after 2 h of incubation, only. No significant alteration was noted for these parameters in comparison to control at Times 0 and 1 h. The total percentage of morphologically abnormal spermatozoa was significantly higher (P<0.05) in the group with the highest copper concentration (46.20 ± 5.54%) in comparison to control (30.60 ± 2.91). Predominant morphological abnormalities were acrosomal changes, knob-twisted flagellum and small heads. Detection of spermatozoa with disordered membrane was carried out for groups with higher copper concentrations and control, using Annexin analysis. Analysis showed higher occurrence of positive spermatozoa in the copper-exposed groups. Some Annexin positive reactions from all spermatozoa were detected in the control group. In copper-exposed groups positive reaction proved alteration in anterior part of head (acrosome) and in connection segment (mid-piece) of spermatozoa. Detected data evidently confirm adverse effects of high copper sulphate concentrations in rabbit semen on parameters of spermatozoa motility, morphology and membrane integrity. This paper also indicates the lowest possible toxic concentration of copper (3.70 μg CuSO4/mL) to rabbit spermatozoa in relation to motility.

Cadmium toxicity at low concentration on rabbit spermatozoa motility, morphology and membrane integrity in vitro

In this study the effect of cadmium on various parameters of spermatozoa motility, morphology as well as on the spermatozoa membrane integrity in rabbits was analyzed in vitro, experimental concentrations ranging from 0.62 to 0.98 μ g CdCl2/mL. Pooled rabbit (n = 5) semen was cultured in vitro with cadmium and subsequently diluted to various experimental concentrations apart from control which received no cadmium exposure. Using computer assisted semen analysis method (CASA) we detected decrease of total motility with in the higher concentration range at Time 0. However, with increasing time (after 1 and 2 h of culture), cadmium exerted deleterious effect leading to significant motility reduction in comparison to control. A similar trend was exhibited in case of progressive motility, too. Most of the spermatozoa distance and velocity parameters detected no significant change in comparison to control at the beginning of culture (Time 0), although the toxic effect became significant (P < 0.05) with the passage of culture time (Times 1 and 2 h) in all concentrations. Analysis of spermatozoa morphology detected significant (P < 0.05) alterations at higher concentrations. At higher concentrations acrosomal changes, head without flagellum/separated flagellum, broken flagellum and other abnormalities were significantly higher (P < 0.05), while knob–twisted flagellum and small heads differed significantly (P < 0.05) in comparison to control at all concentrations. In regards to flagellum torso, flagellum ball and retention of cytoplasmic drop statistically higher values (P < 0.05) were noted at the maxium experimental concentration only. Annexin analysis for detection of spermatozoa with disordered membranes revealed higher occurrence of positive spermatozoa in cadmium exposed groups. Annexin–positive reactions suggested alterations in anterior part of head (acrosome) and in flagellum (mitochondrial segment) of spermatozoa. This paper underlines that cadmium is highly toxic for rabbit spermatozoa, as visualized by the toxic effects on parameters of spermatozoa motility, morphology and membrane integrity. The toxic effect is more drastic at higher concentrations. This study also indicates that cadmium requires a minimum one hour incubation time to exert its deletorious effects on various parameters of spermatozoa, particularly at low concentrations.

In vitro effect of nickel on bovine spermatozoa motility and annexin V-labeled membrane changes

In this study the effect of in vitro culture of bovine spermatozoa with nickel (NiCl2) on spermatozoa motility and membrane changes was analyzed. The spermatozoa motility significantly decreased after 120 min of culture at the concentration of 1000 μm Ni ml−1 (P < 0.05) and after 240 min of culture at the concentration of 500 and 1000 μm Ni ml−1 (P < 0.001) as compared with control. The progressive motility was the highest in the control group and in the groups with the lowest nickel concentrations (7.8 and 125 μm Ni ml−1). The progressive spermatozoa motility was significantly altered even after 30 min of culture in the group with the highest nickel concentration (1000 μm Ni ml−1). A significant decrease in progressive motility from the concentration of 250 μm Ni ml−1 was detected after 240 min of culture. Concentrations from 125 μm Ni ml−1 in various time periods of culture stimulated spermatozoa motility after 30 min (P < 0.001), but later an inhibitory effect was noted. After 240 min of in vitro spermatozoa culture with 125 μm Ni ml−1 a typical Annexin V fluorescence reaction was detected. Fluorescence was detected in mitochondrial segment of bovine spermatozoa. In spermatozoa exposed to higher nickel concentrations the Annexin V‐positive reaction was detected also on the spermatozoa head membrane. In the group with the highest concentration and the longest time of exposure (1000 μm Ni ml−1; 240 min) the apoptotic Annexin‐positive regions were detected not only in the mitochondrial part, but also in the spermatozoa head (acrosomal and postacrosomal part), showing significant alteration of spermatozoa membrane integrity. Copyright

Diagnostic application of oxidation-reduction potential assay for measurement of oxidative stress: clinical utility in male factor infertility

The objectives of this study were to: (i) describe a protocol measuring the oxidation-reduction potential (ORP) by MiOXSYS System as an alternative method of seminal oxidative stress (OS) testing; (ii) establish a reference value for static ORP (sORP) to distinguish between controls and male factor infertility patients; (iii) evaluate intra-observer and inter-observer reliability; and (iv) examine association of sORP with sperm parameters predictive of male factor infertility. Elevated levels of sORP were seen in infertile patients (6.22 ± 1.10 mV/106 sperm/ml) compared with controls (1.59 ± 0.29 mV/106 sperm/ml) (P = 0.004). A sORP cut-off value 1.36 mV/106 sperm/ml identified normal semen and abnormal semen quality with a sensitivity 69.6%, specificity 83.1%, positive predictive value 85.3% and negative predictive value 65.9%. The test demonstrated strong intra-observer (CV 8.39%) and inter-observer reliability (correlations >0.97). Higher sORP levels were associated with poor sperm parameters across the fertility status of subjects. Negative correlations were noted with sperm parameters (concentration, total sperm count, motility and morphology) indicating these male infertility parameters are related to OS. In conclusion, the introduction of ORP as a novel clinical test for assessment of OS will help clinicians to better diagnose and manage male factor infertility patients.

In vitro toxicity of mercuric chloride on rabbit spermatozoa motility and cell membrane integrity

In this in vitro study the effects of mercuric chloride on the motility and structural integrity of rabbit spermatozoa were investigated. The spermatozoa motility was evaluated using CASA method and Annexin analysis was used for detection of structural changes. The concentration of mercury in the medium varied from 5.0 to 83.3 μ g HgCl2/mL. At Time 0 the highest motility was detected in the control group (67.09 ± 8.72%). Motility in groups with mercury administration was lower in comparison with control. Significant differences were detected in groups with 50.0–83.3 μ g HgCl2/mL (P < 0.001) at Time 0. After 60 and 120 minutes of incubation with mercuric chloride the motility significantly decreased almost in all experimental groups. Progressive motility had a decreasing trend in all experimental groups. At time 60 and 120 significant differences were noted in the group receiving 6.25–83.3 μ g HgCl2/mL. Significant differences were detected in all experimental groups, except the group with the lowest mercuric chloride administration. The concentration-dependent decrease of spermatozoa progressive motility up to 50% of control was detected for groups receiving 50.0 – 83.3 μ g HgCl2/mL at Time 0, for groups receiving 12.5–83.3 μ g HgCl2/mL at Time 60 and 120, decreasing from 36.46 ± 18.73% to 1.03 ± 2.50%. Detailed evaluation of spermatozoa distance (DAP, DCL, and DSL) and velocity (VAP, VCL, and VSL) parameters as well as straightness (STR), linearity (LIN), wobble (WOB), amplitude of lateral head displacement (ALH) and beat cross frequency (BCF) of spermatozoa revealed decrease in groups with the highest mercury concentration in comparison with the control group at all time periods. Detection of spermatozoa with disordered membrane was carried out for groups with higher mercury concentrations and control, using Annexin analysis. Analysis showed higher occurrence of positive spermatozoa in the mercury exposed groups. Some Annexin positive reactions from all spermatozoa were detected in the control group. In mercury-exposed groups positive reaction proved alteration in anterial part of head (acrosome), connection part (connection piece) and in mitochondrial segment. Detected data evidently confirm adverse effects of high mercuric chloride concentrations in rabbit semen on spermatozoa motility parameters.