Factor In Seminal Plasma Research Articles

Localization of β-Nerve Growth Factor in the Stallion Reproductive Tract.

β-Nerve growth factor (β-NGF) is a protein produced in the reproductive tract of camelids (camels, llamas, and alpacas) that has been identified as the ovulation inducing factor in seminal plasma. β-NGF from seminal plasma deposited into the reproductive tract of the female camelid acts systemically to stimulate the secretion of luteinizing hormone (LH) from the anterior pituitary, which in turn induces follicle maturation and ovulation. The objectives of the present study were to determine if β-NGF is present in the reproductive tract of the stallion and identify the specific site(s) of production. The hypotheses were that β-NGF would be present in the stallion reproductive tract and would primarily be localized in Sertoli cells of the testes and the prostate gland. Immunohistochemistry on paraffin-embedded paraformaldehyde-fixed tissues was performed using a rabbit polyclonal anti-β-NGF antibody on a total of six male equine reproductive tracts, including a one-day old colt, a one-year-old colt, and four adult stallion tracts. Strong immunostaining was observed in the efferent ducts of the testes and the epithelial cells of the prostate, seminal vesicles, bulbourethral glands, and ampullae. Weaker β-NGF staining was noted in Leydig cells, Sertoli cells, and spermatogonia within the testes and in epithelial cells of the epididymis. In conclusion, immunohistochemistry revealed that β-NGF is present in the stallion reproductive tract, and the protein is primarily present in the efferent ducts of the testes and in all accessory sex glands.

117 Nerve growth factor in seminal plasma and its association with extracellular vesicles in South American camelids.

Reproduction, Fertility and Development is an international journal publishing original research , review and comment in the fields of reproduction and developmental biology in humans, domestic animals and wildlife

89 Does progesterone block the nerve growth factor–induced luteinizing hormone surge in llamas?

The central inhibitory effects of progesterone on gonadotrophin secretion have been well documented in several species, including camelids. Nerve growth factor (NGF) in seminal plasma triggers ovulation in camelids and is thought to act at the level of the hypothalamus. The objective of the study was to determine the effect of progesterone on NGF-induced LH release in llamas. In Experiment 1, llamas were assigned to a low, medium, or high progesterone group (n=4 per group). The low progesterone group consisted of non-mated (non-ovulatory) llamas, the medium progesterone group consisted of mated llamas (luteal phase; 3–4 weeks pregnant), and the high progesterone group consisted of non-mated llamas given a single intramuscular (IM) dose of progesterone (300mg IM, Progesterone BioRelease LA). A jugular catheter was placed, and the following day llamas were given an intravenous dose of 1mg of NGF isolated from seminal plasma. Blood samples were taken every 30min from 1h before to 5.5h after NGF treatment. In Experiment 2, the pituitary LH response to gonadotrophin-releasing hormone (GnRH) was compared between llamas treated with either Progesterone BioRelease LA or saline (n=4 per group). Sixteen hours later, llamas in both groups were given 50µg of gonadorelin (GnRH) IV, and blood samples were collected by jugular puncture at 0.5h before and 0, 1, 2, and 4h after GnRH. Blood samples were centrifuged, and plasma was stored frozen until radioimmunoassay for LH and progesterone. Data are presented as mean±s.e.m. Data were analysed by one-way ANOVA for single-point and repeated-measures, and independent or paired t-tests. In Experiment 1, plasma progesterone concentrations in the low, medium, and high progesterone groups were 0.6±0.3, 8.2±0.4, and 14.9±1.2ng mL−1, respectively, at the time of NGF treatment (P<0.05). Circulating concentrations of LH did not differ among progesterone groups (treatment, P=0.49; time, P<0.01; treatment×time interaction, P=0.65). In all groups, LH concentrations were elevated within 30min of NGF administration, reached a peak by 2h, and remained elevated beyond the sampling period. Comparison of samples collected during the pretreatment period (i.e. −60, −30, and 0min), however, revealed that plasma LH concentrations in the high progesterone group were half that of the low and medium progesterone groups (P<0.03). In Experiment 2, plasma progesterone concentrations in the progesterone- and saline-treated groups were 12.7±2.2 and 1.3±0.3ngmL−1, respectively (P<0.01). Despite the difference in circulating progesterone concentrations, the LH response to GnRH treatment was not different between groups (treatment group, P=0.43; time, P<0.01; treatment×time interaction, P=0.84). Results demonstrate a suppressive effect of progesterone on basal LH release in llamas, but no suppressive effect on NGF- or GnRH-induced surge release from the pituitary gland. Results are consistent with the hypothesis that the site of action of NGF is downstream of the hypothalamic site of action of progesterone. This research was supported by NSERC Canada.

Natural and controlled ovulation in South American camelids.

The four species of New World camelids and 2 species of Old World camelids derived from a common ancestor in North America. The reproductive characteristics, particularly those involving ovarian function and ovulation, are remarkably similar among the 6 living species of camelids, so much so that interspecies hybrids of nearly all possible combinations have been documented. Camelids are induced-ovulators, triggered by an ovulation-inducing factor in seminal plasma. The timing and mechanism of endocrine events leading to ovulation are discussed, as well as the discovery, identification and mode of action of the seminal factor responsible. The applied aspects of our present understanding are discussed with specific reference to controlled induction of ovulation, ovarian synchronization, and superovulation. Emphasis has been given to the literature on llamas and alpacas, with some reference to studies done in wild species of South American camelids and Old World camels.

Monitoring and controlling follicular activity in camelids

This paper reviews that state of our knowledge concerning follicular wave dynamics, monitoring and manipulation. All camelids have overlapping follicular waves in absence of ovulation which is induced by a seminal plasma factor (βNGF). The interval between follicular waves varies. The size of the ovulatory follicle varies between 11 and 25 mm in camels and between in 6 and 13 mm in South American Camelids. The interval between induction of ovulation and next ovulatory follicle is 15 ± 1 day for all camelids. Follicular activity is best monitored by transrectal ultrasonography. Progesterone therapy for 7–15 days seems to suppress follicular dominance but does not completely inhibit follicular recruitment. Combination of estradiol and progesterone seems to provide better control of follicular activity. Both methods have provided variable results in the synchronization of follicular waves. Combination of induction of ovulation with GnRH and luteolysis at predetermined times shows some promise in synchronization of follicular dominance. These synchronization protocols require further investigation in order to provide practical approaches for fixed-time breeding. Ovarian superstimulation with FSH and eCG alone or in combination is somewhat successful. The best results are obtained when treatment is initiated at the emergence of a new follicular wave after induction of ovulation or following treatment with progesterone for 7–14 days. However, response remains extremely variable particularly in terms of ovulation rate and number of recovered embryos. Sources of this variability need to be studied including the effects of season, nutrition, doses and frequency of administration of gonadotropin.

Identification of beta-nerve growth factor in dromedary camel seminal plasma and its role in induction of ovulation in females

The main objective of this study was to demonstrate the effect of seminal plasma ovulation inducing factor (OIF) on ovulation in female camels. Seminal plasma was fractionated using gel filtration chromatography, and two protein peaks were obtained and analysed by western blotting. The effect of the bioactive protein fraction (OIF/β-NGF) was tested by intramuscular injection (1 ml) in synchronized females with the following treatments: PBS (negative control group, n = 3); 20 µg Buserelin (GnRH analogue, positive control group; n = 3); and purified OIF with doses of 1 and 2 mg (n = 5, each treatment). Blood samples were collected every two days from day 0 until 14 days post-treatment, and the progesterone concentration was assessed. The obtained results showed that the OIF is highly present in the seminal plasma of dromedary camels as a protein with a molecular mass of approximately 14 kDa. It was detected as a beta-Nerve Growth Factor, named Cam-β-NGF. The effect of this molecule on ovulation was clearly demonstrated by the significant increase of the plasma progesterone concentration in the treated female groups (1 and 2 mg of Cam-β-NGF) as observed in Buserelin group. In summary, intramuscular injection of β-NGF isolated from dromedary camel seminal plasma induces ovulation in females with similar rate to Buserelin treatment.

Ovulation-inducing factor (OIF/NGF) in seminal plasma: a review and update.

The ovulation-inducing effect of seminal plasma was first reported in Bactrian camels over 30years ago, and the entity responsible was dubbed 'ovulation-inducing factor' (OIF). More recent studies, primarily in llamas and alpacas, characterized the biological and chemical properties of OIF and ultimately identified it as βNGF. This recent discovery has allowed a convergence of knowledge previously separated by discipline and by mechanism; that is, neurobiology and reproductive biology, and autocrine/paracrine vs endocrine. To preserve this link, we have referred to the seminal factor as OIF/NGF. As a highly conserved protein, the implications of discoveries related to OIF/NGF in reproductive tissues extend beyond the camelid species, and results of recent studies show that the presence and function of OIF/NGF in seminal plasma are conserved among species considered to be induced ovulators as well as those considered to be spontaneous ovulators. The abundance of OIF/NGF in seminal plasma and the effects of seminal plasma on ovarian function strongly support the idea of an endocrine mode of action (i.e. systemic distribution with distant target tissues). This review is intended to provide an update on the progress in our understanding of the nature of OIF/NGF in seminal plasma and its effects on reproductive function in the female, including the effects of dose and route of administration, evidence for ovarian effects in other species, tissue sources of OIF/NGF and early findings related to the mechanism of action of OIF.

Evaluation the Effect of Interleukin-6 and Tumor Necrosis Factor in Semen Quality of Infertile Men with Varicocele.

Objective: The study was designed to evaluation of effect Interleukin-6 and Tumor necrosis factor in seminal plasma to semen quality in infertile men with varicocele. Methods: A descriptive correlation study was conducted in specialized infertility center / teaching AL-Sadder medical city in Najaf city from first of April 2014 to the first of June 2014.Sample was selected that consisted of (75) infertile men with varicocele, and (25) healthy subject as control, their age between (20-40) years old. A questionnaire format and observational checklist were used which including marriage period, excluding from chronic disease like diabetic, cancer, sexual transmitted disease. The data were collected through the utilization of questionnaire and the structure interview technique with varicocele patients. Data was analyzed by using T-test and Z-test Results: The result of the study sample have revealed that 42% from all subjects has elevated Interleukin-6 concentration in seminal plasma ,and also the elevation Interleukin-6 level in seminal plasma has inversely correlation R = -0.58 with decreased in sperm motility ,also has inversely correlation R = -0.30 with low sperm count. From other hand 41% from all subjects has elevated Tumor necrosis factor levels in seminal plasma ,and also the elevation Tumor necrosis factor concentration in seminal plasma has inversely correlation R = -0.17 with decreased in sperm motility ,also has inversely correlation R = -0.25 with low sperm count. Conclusions: They study concluded there was a significant difference between elevation of Interleukin-6 and Tumor necrosis factor levels in seminal plasma in infertile men with varicocele, and they study concluded there was a significant correlation between increased levels of Interleukin-6 and Tumor necrosis factor in seminal plasma with reduce sperm count and motility . Recommendations: the study recommended that: Varicocele examination and diagnosis should be done to all infertile male. Varicocele patients with abnormal seminal fluid examination should be estimated concentration of Interluekin-6 and Tumor necrosis factor in seminal plasma

Bioactivity of ovulation inducing factor (or nerve growth factor) in bovine seminal plasma and its effects on ovarian function in cattle

To understand the role of ovulation-inducing factor (or nerve growth factor) (OIF [NGF]) in bovine seminal plasma, we (1) used an in vivo llama bioassay to test the hypothesis that bovine seminal plasma induces ovulation and CL development in llamas similar to that of llama seminal plasma when the dose of seminal plasma is adjusted to ovulation-inducing factor content (experiment 1) and (2) determined the effect of bovine seminal plasma on the interval to ovulation and luteal development in heifers (experiment 2). Within species, seminal plasma was pooled (n = 160 bulls, n = 4 llamas), and the volume of seminal plasma used for treatment was adjusted to a total dose of 250 μg of ovulation-inducing factor. In experiment 1, mature female llamas were assigned randomly to four groups and treated intramuscularly with either 10 mL of PBS (negative control, n = 5), 50-μg GnRH (positive control, n = 5), 6-mL of llama seminal plasma (n = 6), or 12 mL of bull seminal plasma (n = 6). Ovulation and CL development were monitored by transrectal ultrasonography. In experiment 2, beef heifers were given a luteolytic dose of prostaglandin followed by 25-mg porcine LH (pLH) 12 hours later to induce ovulation. Heifers were assigned randomly to three groups and given 12 mL bovine seminal plasma intramuscularly 12 hours after pLH treatment (n = 10), within 4 hours after ovulation (n = 9), or no treatment (control, n = 10). Ovulation was monitored by ultrasonography every 4 hours, and the CL development was monitored daily until the next ovulation. In experiment 1, ovulation was detected in 0/5, 4/5, 4/6, 4/6 llamas in the PBS, GnRH, llama seminal plasma, and bovine seminal plasma groups, respectively (P < 0.05). Luteal development was not different among groups. In experiment 2, the interval to ovulation was more synchronous (range: 4 vs. 22 hours; P < 0.0001) in heifers treated with seminal plasma before ovulation compared with the other groups. Luteal development was not different among groups; however, plasma progesterone concentrations tended to be greater in the postovulation treatment group compared with other groups. In summary, results confirmed the presence of bioactive ovulation-inducing factor in bull seminal plasma and supported the hypothesis that bovine and llama seminal plasma have similar ovulatory effects, using a llama bioassay. Treatment with bovine seminal plasma resulted in greater synchrony of ovulation in heifers pretreated with pLH. Plasma progesterone concentration tended to be higher in heifers given bovine seminal plasma within 4 hours after ovulation, suggesting that bovine ovulation-inducing factor is luteotrophic.

Identification of a decapacitation factor in goat seminal plasma

The seminal plasma is complex mixture of the secretions of the testis, epididymis and the accessory glands. The secretory proteins of the epididymal fluid as well as those of the accessory glands appear along with spermatozoa as semen at the time of ejaculation. Some of these proteins coat the sperm surface and prevent the premature activation of the spermatozoa in the female reproductive tract. The activation of spermatozoa, which requires the removal of sperm- coating proteins, is necessitated for the entry of the spermatozoa into the oocyte at the site of fertilization. The adsorption of radiolabelled seminal plasma proteins on the sperm surface showed an absence of high molecular weight proteins, thus suggesting the reorganization of the sperm surface proteins during the process of capacitation. The effect of lyophilized goat seminal plasma proteins revealed an inhibitory effect on the capacitation after an initial preincubation of 3.5 h. The absorption of radiolabelled seminal plasma proteins on the sperm surface showed an absence of high molecular weight proteins, thus suggesting the reorganization of the sperm surface proteins during the process of capacitation. The amount of protein for a 50% decrease in the acrosome reaction as compared to the control in a dose- dependent response, ID50 is 2.45 mg. The factor is removed by the help of ultracentrifugation for 6 h and the pellet obtained showed an inhibitory effect at an initial preincubation of 3.5 h and the value of ID50 determined is 1.25 mg. An apparent mechanism of capacitation involves the rearrangement of sperm surface proteins and removal of the factor by ultracentrifugation shows that it is a high molecular weight protein.

248 DISTRIBUTION OF OVULATION-INDUCING FACTOR IN MALE REPRODUCTIVE TISSUES OF LLAMAS

We have recently reported that the ovulation-inducing factor (OIF) in seminal plasma is the well-conserved neurotrophin, nerve growth factor. This protein has been identified in the ejaculates of a variety of species using both in vivo and in vitro bioassays. The role of OIF in the ejaculate is evident in camelids. Irrespective of whether a male is intact or vasectomised, ejaculation of this protein during copulation stimulates an increase in circulating LH in the female, which subsequently leads to ovulation. The purpose for OIF in species that are spontaneous ovulators, however, remains unclear. We hypothesise that OIF production is restricted to the secretory epithelium of accessory glands of the male, specifically the prostate gland, because of its conservation among mammals. The objective of the present study was to determine the sites of OIF secretion in the llama that contribute to high concentrations found in the ejaculate. The mucosa, submucosa, and muscularis layers of the reproductive organs (testis, epididymis, ductus deferens, and penis) and accessory sex glands (ampulla, prostate gland, and bulbourethral gland) from mature male llamas (n = 2) were probed with polyclonal rabbit anti-nerve growth factor. The secondary antibody used was horseradish peroxidase-conjugated goat-anti-rabbit immunoglobulin G. The distribution and intensity of OIF-secreting cells were identified and compared among tissues using a four-point scale. The quantity of OIF detected was highest in mucosal prostatic cells. The protein was strongly localised in the apical region of epithelial cells and frequently found within the glandular lumen. The seromucus-secreting epithelium of ampullary glands showed no reaction to OIF, whereas the bulbourethral gland epithelium showed an intermediate response. The presence of OIF was not detected in the epithelium of the penile urethra, epididymis (caput, corpus, or cauda), or seminiferous tubules. A diffuse distribution of the protein was, however, detected in the stroma of the testes, epididymides, and accessory glands. We conclude that cells that secrete OIF are distributed unequally among accessory sex glands in llamas. The bulk of OIF is produced by the prostate gland, with minimal to no contributions by the bulbourethral and ampullary glands. Future studies involve species comparisons and relating the size of the prostate gland to the concentration of OIF within an ejaculate. Research supported by the Natural Sciences and Engineering Research Council of Canada.

The nerve of ovulation-inducing factor in semen

A component in seminal fluid elicits an ovulatory response and has been discovered in every species examined thus far. The existence of an ovulation-inducing factor (OIF) in seminal plasma has broad implications and evokes questions about identity, tissue sources, mechanism of action, role among species, and clinical relevance in infertility. Most of these questions remain unanswered. The goal of this study was to determine the identity of OIF in support of the hypothesis that it is a single distinct and widely conserved entity. Seminal plasma from llamas and bulls was used as representative of induced and spontaneous ovulators, respectively. A fraction isolated from llama seminal plasma by column chromatography was identified as OIF by eliciting luteinizing hormone (LH) release and ovulation in llamas. MALDI-TOF revealed a molecular mass of 13,221 Da, and 12-23 aa sequences of OIF had homology with human, porcine, bovine, and murine sequences of β nerve growth factor (β-NGF). X-ray diffraction data were used to solve the full sequence and structure of OIF as β-NGF. Neurite development and up-regulation of trkA in phaeochromocytoma (PC(12)) cells in vitro confirmed NGF-like properties of OIF. Western blot analysis of llama and bull seminal plasma confirmed immunorecognition of OIF using polyclonal mouse anti-NGF, and administration of β-NGF from mouse submandibular glands induced ovulation in llamas. We conclude that OIF in seminal plasma is β-NGF and that it is highly conserved. An endocrine route of action of NGF elucidates a previously unknown pathway for the direct influence of the male on the hypothalamo-pituitary-gonadal axis of the inseminated female.

Evidence for the conservation of biological activity of ovulation-inducing factor in seminal plasma

An ovulation-inducing factor (OIF) in the seminal plasma of llamas and alpacas (induced ovulators) and cattle (spontaneous ovulators) suggests that OIF is a conserved constituent of seminal plasma among mammals. In this study, three experiments were designed to determine the biological effects of OIF in different species. In experiment 1, superstimulated prepubertal female CD-1 mice (n=36 per group) were given a single 0.1 ml i.p. dose of 1) phosphate-buffered saline (PBS), 2) 5 μg gonadotropin-releasing hormone (GNRH), 3) 5 IU hCG, or 4) llama seminal plasma. The proportion of mice that ovulated was similar among groups treated with GNRH, hCG, or seminal plasma, and all were higher than the saline-treated group (P<0.001). In experiment 2, female llamas (n=8 or 9 per group) were intramuscularly treated with 1) 2 ml PBS, 2) 1 ml diluted llama seminal plasma, 3) 3 ml equine seminal plasma, or 4) 3 ml porcine seminal plasma. Experiment 3 was the same as experiment 2 except that the dose of equine and porcine seminal plasma was increased to 8 and 10 ml respectively. All llamas that were treated with llama seminal plasma ovulated and none that were treated with saline ovulated (P<0.0001). The proportion of llamas that ovulated in response to equine and porcine seminal plasma was intermediate. We conclude that the mechanism for the biological response to OIF is present in prepubertal CD-1 mice and that OIF is present in equine and porcine seminal plasma.

Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas.

BackgroundThe objective of the present study was to isolate and purify the protein fraction(s) of llama seminal plasma responsible for the ovulation-inducing effect of the ejaculate.MethodsSemen collected from male llamas by artificial vagina was centrifuged and the seminal plasma was harvested and stored frozen. Seminal plasma was thawed and loaded onto a Type 1 macro-prep ceramic hydroxylapatite column and elution was carried out using a lineal gradient with 350 mM sodium phosphate. Three protein fractions were identified clearly (Fractions A, B, and C), where a prominent protein band with a mass of 14 kDa was identified in Fraction C. Fraction C was loaded into a sephacryl gel filtration column for further purification using fast protein liquid chromatography (FPLC). Isocratic elution resulted in 2 distinct protein fractions (Fractions C1 and C2). An in vivo bioassay (n = 10 to 11 llamas per group) was used to determine the ovarian effect of each fraction involving treatment with saline (negative control), whole seminal plasma (positive control), or seminal plasma Fractions A, B or C2. Ultrasonography was done to detect ovulation and CL formation, and blood samples were taken to measure plasma progesterone and LH concentrations.ResultsOvulation and CL formation was detected in 0/10, 10/11, 0/10, 2/11, and 10/11 llamas treated with saline, whole seminal plasma, Fractions A, B and C2 respectively (P < 0.001). A surge in circulating concentrations of LH was detected within 2 hours only in llamas treated with either whole seminal plasma or Fraction C2. Plasma progesterone concentration and CL diameter profiles were greatest (P < 0.05) in llamas treated with Fraction C2.ConclusionOvulation-inducing factor was isolated from llama seminal plasma as a 14 kDa protein molecule that elicits a preovulatory LH surge followed by ovulation and CL formation in llamas, suggesting an endocrine effect at the level of the hypothalamus (release of GnRH) or the pituitary (gonadotrophs).

Ovulation-inducing factor: a protein component of llama seminal plasma

BackgroundPreviously, we documented the presence of ovulation-inducing factor (OIF) in the seminal plasma of llamas and alpacas. The purpose of the study was to define the biochemical characteristics of the molecule(s) in seminal plasma responsible for inducing ovulation.MethodsIn Experiment 1, llama seminal plasma was centrifuged using filtration devices with nominal molecular mass cut-offs of 30, 10 and 5 kDa. Female llamas (n = 9 per group) were treated i.m. with whole seminal plasma (positive control), phosphate-buffered saline (negative control), or the fraction of seminal plasma equal or higher than 30 kDa, 10 to 30 kDa, 5 to 10 kDa, or < 5 kDa. In Experiment 2, female llamas (n = 7 per group) were given an i.m. dose of seminal plasma treated previously by: 1) enzymatic digestion with proteinase-K, 2) incubation with charcoal-dextran, 3) heating to 65°C, or 4) untreated (control). In Experiment 3, female llamas (n = 10 per group) were given an i.m. dose of pronase-treated or non-treated (control) seminal plasma. In all experiments, llamas were examined by transrectal ultrasonography to detect ovulation and CL formation. Ovulation rate was compared among groups by Fisher's exact test and follicle and CL diameters were compared among groups by analyses of variance or student's t-tests.ResultsIn Experiment 1, all llamas in the equal or higher than 30 kDa and positive control groups ovulated (9/9 in each), but none ovulated in the other groups (P < 0.001). In Experiment 2, ovulations were detected in all llamas in each treatment group; i.e., respective treatments of seminal plasma failed to inactivate the ovulation-inducing factor. In Experiment 3, ovulations were detected in 0/10 llamas given pronase-treated seminal plasma and in 9/10 controls (P < 0.01).ConclusionsWe conclude that ovulation-inducing factor (OIF) in llama seminal plasma is a protein molecule that is resistant to heat and enzymatic digestion with proteinase K, and has a molecular mass of approximately equal or higher than 30 kDa.

Immunoglobulin-Fc binding factor in human male reproductive organs

Human seminal plasma, testis, seminal vesicle, epididymis, and prostate contain a component with an estimated Mr of 20 kD that binds human immunoglobulin-Fc. The factor did not bind goat-IgG-Fc, immunoglobulins of human, rat, mouse, goat, horse, or rabbit sera and did not interact with antibodies raised against Fc gamma receptors. The present findings show that this Fc binding factor in seminal plasma is a secretory product of the testis and accessory sex organs. It binds human Ig-Fc but does not meet the criteria of an Fc receptor. Additional IgG-Fc binding proteins with estimated Mr of 90, 88, and 86 kD were detected in the prostate, testis, and seminal vesicle, respectively.

Seminal plasma non-heparin binding proteins (NHBP) reduce the cryoinjury to buffalo cauda epididymal spermatozoa induced by heparin binding proteins (HBP)

Previous cryopreservation studies with buffalo cauda epididymal spermatozoa have reported a deleterious effect of seminal plasma heparin binding protein (HBP). The amount of HBP used in these studies was meager compared to the normal level of HBP in the buffalo ejaculate, still the damage induced upon the spermatozoa was substantial when compared to that incurred to the spermatozoa during routine freezing of ejaculated semen. Thus there might be some factor(s) in the seminal plasma, which reduce the deleterious effect of HBP on spermatozoa during cryopreservation of ejaculated semen. This study was conducted to investigate for the presence of any such factor in buffalo seminal plasma. Seminal plasma proteins were separated on their heparin binding properties as heparin binding (HBP) and non-heparin binding (NHBP). The separated proteins were added to the extender of buffalo cauda epididymal semen for cryopreservation either alone or in combination. The spermatozoa were assessed for progressive motility, viability, acrosomal integrity and response to hypo-osmotic solution test (HOST) at prefreeze and post-thaw stages of cryopreservation. NHBP was found to provide some degree of protection to buffalo spermatozoa against cryopreservation stress as well as the deleterious effect of HBP during cryopreservation.

Seminal plasma and male factor signalling in the female reproductive tract

In mammals, insemination results in the transmission of seminal factors that act, in the female reproductive tract, to promote sperm survival, to "condition" the female immune response to tolerate the conceptus and to organise molecular and cellular changes in the endometrium to facilitate embryo development and implantation. These events are initiated when signalling agents, including transforming growth factor-beta and other cytokines and prostaglandins secreted by seminal vesicle and prostate glands, interact with epithelial cells in the cervix and uterus to activate cytokine synthesis and to induce cellular and molecular changes resembling a classical inflammatory cascade. The consequences are the recruitment and activation of macrophages, granulocytes and dendritic cells, which have immune-regulatory and tissue-remodelling roles that culminate in improved endometrial receptivity to the implanting embryo. Cytokines elicited by seminal activation have embryotrophic properties and also contribute directly to the optimal development of the early embryo. This review summarises our current understanding of the physiology of responses to seminal plasma in the female reproductive tract and considers the evolutionary significance of seminal plasma in influencing female tissues to promote the success of pregnancy.

Isolation of Ovulation-inducing Factors in the Seminal Plasma of Bactrian Camel (Camelus bactrianus) by DEAE-cellulose Chromatography

Ovulation in the Bactrian camel (Camelus bactrianus) depends upon the ovulation-inducing factor in the seminal plasma; however, little research has been conducted to isolate and identify the factor. The current study attempts to isolate and identify the bioactive fractions from the seminal plasma of Bactrian camel. The seminal plasma was fractionated by diethylamino-ethylcellulose (DEAE)-cellulose chromatography and five protein fractions were obtained. The bioactive of each fraction was estimated by rat pituitary tissue culture in vitro and by the intramuscular injection of the bioactive fraction to the female camels in vivo. The concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in the pituitary culture media before and 6 h after the addition of each fraction and in the peripheral blood plasma collected from the camel immediately before and hourly after the injection of the active fraction were measured by radioimmunoassay. The results demonstrated that the third fraction (L3) had the bioactive potential to stimulate the release of LH in vitro from 11.82 +/- 1.77 to 25.63 +/- 3.84 mIU/ml after the addition of L3 to the culture media. The in vivo concentrations of LH in the blood plasma of the camel increased from 6.43 +/- 0.14 before to 15.50 +/- 2.64 ng/ml 6 h after injection of L3. However, the concentrations of FSH did not show any significant changes either in vitro or in vivo. The results clearly demonstrated the existence of LH-releasing associated fractions in the seminal plasma that appears to be separated by DEAE-cellulose matrix and the isolated L3 fraction might be the ovulation-inducing factor or one of its components.

Stem cell factor in human seminal plasma as a marker for spermatogenesis

Objectives. To measure the level of stem cell factor (SCF) in human seminal plasma to determine whether SCF may be useful in evaluating the ability to produce sperm and search the role of SCF in the testes. Methods. We measured the level of SCF in seminal plasma obtained from 108 males, including idiopathic azoospermia due to germ cell aplasia (n = 10), oligospermia (n = 50), asthenospermia (n = 31), and normospermia (n = 17). The expression of SCF messenger ribonucleic acid in the human testis was evaluated by reverse transcriptase polymerase chain reaction (RT-PCR). The correlation between its level and clinical findings was also evaluated. Results. RT-PCR showed a larger form that encoded the soluble protein and a smaller form that encoded the membrane-associated form of SCF in the human testis. The similar ratio of the larger form to the smaller one was observed both in the testis of normal and oligospermic men. The level of SCF is significantly correlated with the sperm count ( r = 0.214; P <0.05). Conclusions. The level of SCF in seminal plasma appeared to predict the ability to produce sperm. Thus, this factor may play an important role in spermatogenesis.