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2.
  • AHLGREN, GÖRAN, et al. (author)
  • Impaired Secretory Function of the Prostate in Men With Oligo‐Asthenozoospermia
  • 1995
  • In: Journal of Andrology. - 0196-3635. ; 16:6, s. 491-498
  • Journal article (peer-reviewed)abstract
    • ABSTRACT: The secretory function of the human prostate and the seminal vesicles is a prerequisite for gel formation and liquefaction of semen, but the relation to poor sperm motility and low sperm count in infertile men remains to be clarifyed. Our aim was to evaluate the secretory function of the prostate and the seminal vesicles in normozoospermic men (n=35) and in asthenozoospermic men, who were all also oligozoospermic (n=27). All 62 subjects belonged to couples undergoing routine infertility evaluation. In liquefied seminal fluid we measured the concentrations of fructose and protein C inhibitor (PCI) contributed by the seminal vesicles, PCI complexed to prostate‐specific antigen (PSA), and the prostatic contribution of zinc, PSA, acid phosphatase (PAP), β‐microseminoprotein (β‐MSP), and Znα2‐glycoprotein (Znα2‐GP). The concentration of each prostatic secretory protein correlated significantly with that of zinc (P < 0.01) in both the normozoospermic (NZS) and oligo‐astheno‐zoospermic (OAZS) subgroups, but the PCI concentration did not correlate significantly with that of fructose. There was no significant difference between the NZS and OAZS subgroups in ejaculate volume or secretory contribution from the seminal vesicles, whereas the OAZS subgroup was characterized by significantly lower secretory contributions of Znα2‐GP (P = 0.001), Zn, PSA, PAP (P < 0.01), and β‐MSP (P < 0.05). The two subgroups did not differ significantly in the serum concentration of luteinizing hormone (LH), testosterone, or sex hormone‐binding globulin (SHBG). The results thus suggest the secretory contribution of major prostatic proteins and zinc per ejaculate to be significantly decreased in oligo‐asthenozoospermic men. The importance of this finding in relation to poor sperm count and motility as indicators of impaired gonadal function requires further investigation. 1995 American Society of Andrology
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  • Bjartell, Anders, et al. (author)
  • Distribution and tissue expression of semenogelin I and II in man as demonstrated by in situ hybridization and immunocytochemistry
  • 1996
  • In: Journal of Andrology. - 0196-3635. ; 17, s. 17-26
  • Journal article (peer-reviewed)abstract
    • Semenogelin I and II (Sgl, Sgll) are two separate gene products of chromosome 20 with extensive (80%) identity in primary structure. They are mainly responsible for immediate gel formation of freshly ejaculated semen. Degradation of Sgl and Sgll is due to the proteolytic action of prostate-specific antigen (PSA); it results within 5-15 minutes in liquefaction of semen and release of progressively motile spermatozoa. By means of cDNA cloning and Northern blots, Sgl and Sgll transcripts have previously been shown to be abundant in human seminal vesicles, but Sgll alone is suggested to be expressed at low levels in the epididymis. To characterize the expression and tissue distribution of Sgl and Sgll in greater detail, we produced monoclonal immunoglobulin Gs (lgGs for immunocytochemistry (lCC) and specific [35S]-, digoxigenin-, or alkaline phosphatase-labeled 30-mer antisense probes to Sgl and Sgll for in situ hybridization (lSH). Immunocytochemical staining for both Sgl and Sgll, and lSH detection of both Sgl and Sgll transcripts, were demonstrated in the cytoplasm of seminal vesicle epithelium. lSH showed Sgll alone to be expressed in the epithelium of the epididymal cauda. Neither lCC nor lSH yielded any evidence of Sgl or Sgll expression in caput or corpus epithelium or in any stromal cells of the epididymis. Consistent with our previous findings using polyclonal lgG, monoclonal anti-Sgll Sgll lgGs identified epitopes on the posterior head, midpiece, and tail of ejaculated spermatozoa. Spermatozoa in the epididymal cauda were also immunoreactive, but those in the caput or corpus region of the epididymis as well as those in the testis were negative. As shown by lCC, neither Sgl nor Sgll were expressed in the testis, the prostate, the female genital tract, or other normal human tissue specimens. Although the significance of Sg attachment to epididymal and ejaculated spermatozoa remains to be established, monoclonal anti-Sg lgG might prove useful in establishing the origin of seminal vesicle tissue components in prostate core biopsies or other biopsy specimens.
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  • Caballero, Ignacio, et al. (author)
  • Immunolocalization and possible functional role of PSP-I/PSP-II heterodimer in highly extended boar spermatozoa
  • 2006
  • In: Journal of Andrology. - : American Society of Andrology. - 0196-3635 .- 1939-4640. ; 27:6, s. 766-773
  • Journal article (peer-reviewed)abstract
    • PSP-I/PSP-II heterodimer is a major protein of boar seminal plasma which is able to preserve, in vitro, the viability, motility, and mitochondrial activity of highly extended boar spermatozoa for at least 5 hours. However, little is known about the binding pattern of the heterodimer to the sperm plasma membrane and its eventual relation with the maintenance of the sperm functionality. The present study investigated the effect of exposing highly extended boar spermatozoa (11 million/mL) to 1.5 mg/mL of PSP-I/PSP-II for 0.5, 5, and 10 hours at 38 degrees C on sperm characteristics and the changes in PSP-I/PSP-II localization as a result of both the addition of PSP-I/PSP-II to the extender and the incubation time. Exposure of the spermatozoa to PSP-I/PSP-II preserved sperm viability, motility, and mitochondrial activity when compared to nonexposed spermatozoa. This protective effect lasted for 10 hours (P less than.05). After immunolabeling of highly extended semen with rabbit monospecific polyclonal antibody against PSP-I/PSP-11, the percentage of immunopositive spermatozoa declines over time from 71% (0.5 hours) to 49% (10 hours). However, more than 80% of spermatozoa remained labeled during the 10-hour incubation period if PSP-I/PSP-11 was added. Scanning electron microscopy revealed 4 different binding patterns. The heterodimer was mainly localized to the acrosomal area, being redistributed to the postacrosomal area or lost during in vitro incubation. In conclusion, the protective effect of the heterodimer appears to be related to its adhesion to the acrosomal area, and the loss of this protective effect coincides with a stepwise redistribution of PSP-I/PSP-II during incubation.
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  • Cremades, T, et al. (author)
  • Kinematic changes during the cryopreservation of boar spermatozoa
  • 2005
  • In: Journal of Andrology. - : American Society of Andrology. - 0196-3635 .- 1939-4640. ; 26:5, s. 610-618
  • Journal article (peer-reviewed)abstract
    • The present study evaluates the effect that various steps of a conventional cycle of cryopreservation have on the patterns of movement exhibited by boar spermatozoa. Sperm-rich ejaculate fractions collected from 24 mature fertile boars (1 ejaculate per boar) were cryopreserved following a standard freeze-thaw procedure with 0.5-mL plastic straws. Overall sperm motility and the individual kinematic parameters of motile spermatozoa (assessed by the computer-aided sperm analysis system Sperm Class Analyzer [SCA]) were recorded in 5 steps of the cryopreservation procedure. These steps were as follows: 1) at the time that the fresh semen was extended, 2) at 17 degrees C, after sperm concentration by centrifugation and re-extension of the pellet with lactose-egg yolk extender; 3) at 5 degrees C, after added freezing extender; 4) at the time that thawed semen was held in a water bath at 37 degrees C for 30 minutes; and 5) at the time that thawed semen was held in a water bath at 37 degrees C for 150 minutes. Data from individual motile spermatozoa, defined by 7 kinematic parameters (curvilinear velocity [VCL], straight-line velocity [VSL], average path velocity [VAP], linearity [LIN], straightness [STR], mean amplitude of lateral head displacement [ALH], and beat cross frequency [BCF]), were analyzed using a pattern analysis technique (PATN) to identify and quantify populations and subpopulations of motile sperm within the semen samples. After the first cluster analysis, 3 motile sperm populations (P) were identified (P1: progressive and/or vigorous cells [90.4%], P2: poorly progressive cells [8.3%], and P3: nonprogressive cells [1.3%]). These populations remained constant (P greater than .05) throughout the 5-step cryopreservation procedure. A second PATN was carried out within the P1 sperm population, which identified 3 sperm subpopulations (sP) (eg, sP1: cells with progressive and vigorous movement [58.7%], sP2: progressive cells only [24.6%], and sP3: vigorous cells only, hyperactive-like [16.7%]). Although the relative frequency of these 3 subpopulations varied among ejaculates (boars), there was no interaction with any cryopreservation step we examined. Whereas sP1 remained constant (P greater than .05), sP2 and sP3 varied significantly (P less than .05) through the cryopreservation procedure, with the increase in sP3 after centrifugation at 17 degrees C and during cooling at 5 degrees C considered particularly relevant. In conclusion, the present study confirms the heterogeneity of sperm movement patterns in boar semen, patterns that vary through the cryopreservation procedure, especially after removal of the seminal plasma by centrifugation and subsequent extension at 17 degrees C and after the slow cooling at 5 degrees C, when obvious increases in hyperactivated movement appeared. The vast majority of spermatozoa, those exhibiting progressive and vigorous movement, remained constant during the cryopreservation procedure, although the proportion differed among boars.
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  • Ek, P, et al. (author)
  • Exogenous protein kinases A and C, but not endogenous prostasome-associated protein kinase, phosphorylate semenogelins I and II from human semen
  • 2002
  • In: Journal of Andrology. - 0196-3635. ; 23:6, s. 806-814
  • Journal article (peer-reviewed)abstract
    • Semenogelins I and II are the quantitatively dominating proteins in human semen. They comprise the major part of the sperm-entrapping gel formed at ejaculation, which subsequently liquefies due to proteolysis of the gel-forming proteins by prostate-specific antigen (PSA). The mechanism behind gel formation and its physiological significance is not known. We have studied phosphorylation and dephosphorylation of human semenogelins. Both were phosphorylated by protein kinases A and C (PKA and PKC, respectively) at a rate about 5 times less than that of histone. For PKA, incorporated ( P)phosphate into semenogelin approached a maximum above 1 mol/mol. Corresponding values for phosphorylation of the semenogelins with PKC were greater than 10. There was no change in the sensitivity of phosphosemenogelins to proteolysis by PSA. Serine (PKA) and serine and threonine (PKC) were the phosphate-accepting amino acid residues, and all incorporated (P-32)phosphate could be removed from the semenogelins with human acid phosphatase. Nil or very little phosphate could be detected in purified semenogelins isolated from seminal plasma. In vivo, about half the protein kinase activity in seminal plasma was bound to prostasomes. PKA but not PKC purified from prostasomes could phosphorylate specific substrates, but they could phosphorylate either of the semenogelins.
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14.
  • Ek, Pia, et al. (author)
  • Exogenous protein kinases A and C, but not endogenous prostasome-associated protein kinase, phosphorylate semenogelins I and II from human semen
  • 2002
  • In: Journal of Andrology. - 0196-3635 .- 1939-4640. ; 23:6, s. 806-814
  • Journal article (peer-reviewed)abstract
    • Semenogelins I and II are the quantitatively dominating proteinsin humansemen. They comprise the major part of the sperm-entrappinggel formed atejaculation, which subsequently liquefies dueto proteolysis of thegel-forming proteins by prostate-specificantigen (PSA). The mechanism behindgel formation and its physiologicalsignificance is not known. We have studiedphosphorylation anddephosphorylation of human semenogelins. Both werephosphorylatedby protein kinases A and C (PKA and PKC, respectively) at arateabout 5 times less than that of histone. For PKA, incorporated(32P)phosphateinto semenogelin approached a maximum above 1mol/mol. Correspondingvalues for phosphorylation of the semenogelins with PKCweregreater than 10. There was no change in the sensitivity ofphosphosemenogelinsto proteolysis by PSA. Serine (PKA) and serine andthreonine(PKC) were the phosphate-accepting amino acid residues, andallincorporated (32P)phosphate could be removed from the semenogelinswithhuman acid phosphatase. Nil or very little phosphate could bedetected inpurified semenogelins isolated from seminal plasma.In vivo, about half theprotein kinase activity in seminal plasmawas bound to prostasomes. PKA butnot PKC purified from prostasomescould phosphorylate specific substrates, butthey could phosphorylateeither of the semenogelins.
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  • Elzanaty, Saad, et al. (author)
  • Effects of ejaculation-to-analysis delay on levels of markers of epididymal and accessory sex gland functions and sperm motility
  • 2007
  • In: Journal of Andrology. - : Wiley. - 0196-3635. ; 28:6, s. 847-852
  • Journal article (peer-reviewed)abstract
    • This study aimed to examine the association between the interval from ejaculation to analysis and epididymal and accessory sex gland function in relation to sperm motility. Ejaculates from 1079 men assessed for infertility were analyzed according to World Health Organization guidelines. Biochemical markers were measured in semen to assess the function of the epididymi;s (neutral alpha-glucosidase [NAG]), prostate (prostate-specific antigen [PSA] and zinc), and seminal vesicles (fructose). Three groups were defined according to time from ejaculation to analysis: G <= 30 (24 -30 minutes), G(31-60) (31-60 minutes), and G(>60) (63-80 minutes). The proportion of progressively motile sperm was significantly lower in G(>60) than in G(<= 30) (mean difference, 8.0%; 95% confidence interval [CI], 2.0%-13%) or G(31-60) (mean difference, 6.0%; 95% CI, 1.0%-12%). The proportion of rapid progressive sperm motility was significantly higher in G(<= 30) compared with G(31-60) (mean difference, 3.0%; 95% CI, 1.0%-5.0%) and 6160 (mean difference, 6.0%; 95% 3.0%; 95% 1.0%-10%). Sperm morphology and viability did not vary significantly between the groups. However, PSA levels in G(>60) were 29% and 31% significantly lower than in G(<= 30) (95% CI, 3.0%-54%) and G(31-60) (95% CI, 7.0%-58%), respectively. Moreover, men in G(>60) had 29% and 17% significantly lower zinc compared with those in G(<= 30) (95% CI, 4.0%-69%) and G(31-60) (95% CI, 4.0%-64%), respectively. Levels of NAG and fructose did not differ significantly between the groups. There were negative associations between the ejaculation-to-analysis interval and sperm motility and levels of PSA and zinc. In male infertility assessments, semen analysis should be performed within 60 minutes of ejaculation.
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  • Jonsson, Magnus, et al. (author)
  • Binding of Semenogelin I to Intact Human Spermatozoa Studied by Flow Cytometry and Surface Plasmon Resonance
  • 2010
  • In: Journal of Andrology. - : Wiley. - 0196-3635. ; 31:6, s. 560-565
  • Journal article (peer-reviewed)abstract
    • Approximately 1 in 10 couples is infertile No definite cause can be found in about 25% of those cases Studies have indicated that seminal vesicle secretion functions as an optimizer of fertilization The Zn2+ binding protein semenogelin I (SgI) represents a major fraction of the proteins present in seminal vesicle fluid and it serves as a structural component of the coagulum that is formed after ejaculation Cleavage of SgI by prostate specific antigen results in liquefaction of the coagulum Fragmented SgI has antibacterial effects and inhibits spermatozoa mobility SgI has also been found complexed to eppin on spermatozoa and this complex has been suggested to be of importance for fertility Here we used flow cytometry and surface plasmon resonance to study Sgl regarding its association with spermatozoa and the interaction dependency on Zn2+ The concentration of Zn2+ in seminal plasma is approximately 100 times higher than in blood plasma and the metal ion is known to change the structure of SgI We found that Sgl binds to spermatozoa in a concentration dependent and saturable manner In solution Sgl bound to spermatozoa in a non Zn2+ dependent way whereas immobilized Sgl interacts with spermatozoa only in the presence of Zn2+ It indicates that Sgl must exhibit a specific structure or free flexibility to be able to interact with that ligand Our results indicate that the association of Sgl to spermatozoa is conformation dependent and specific These findings could constitute a basis for the development of a male contraceptive
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  • Jonsson, Magnus, et al. (author)
  • Truncated semenogelin I binds zinc and is cleaved by prostate-specific antigen
  • 2006
  • In: Journal of Andrology. - : Wiley. - 0196-3635. ; 27:4, s. 542-547
  • Journal article (peer-reviewed)abstract
    • Semenogelins I and II are major coagulum-forming proteins in semen, and they are secreted mainly by the seminal vesicles. These proteins bind Zn2+ and act as substrates for prostate-specific antigen and transglutaminase. A variant semenogelin I lacking 60 amino acids has been described that occurs in different populations with an allele frequency of 1%-3%. To better understand the function of the semenogelins in vivo, our aim was to characterize the properties of the variant form and compare with the wild type. Recombinant proteins were synthesized in insect cells, Binding of Zn2+ was studied by titration of metal ions in the presence of a zinc (11) fluorophore chelator. SDS-PAGE was used to visualize the results of cleavage by prostate-specific antigen and cross-linking with transglutaminase. We found that the truncated and wild-type semenogelin molecules had similar Zn2+-binding properties (ie, a stoichiometry of at least 9-10 mol per mol of protein and an average dissociation constant of 5 mu mol/L per site), and they showed also similar susceptibility for degradation by prostate-specific antigen. Furthermore, like the wild-type form, the truncated semenogelin I was able to serve as a substrate for transglutaminase. These findings imply that the studied characteristics do not depend on a well-defined tertiary structure, or that the deletion has no major effect on the structure responsible for these features.
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  • Lövgren, Janita, et al. (author)
  • Measurement of prostate-specific antigen and human glandular kallikrein 2 in different body fluids
  • 1999
  • In: Journal of Andrology. - 0196-3635. ; 20:3, s. 348-355
  • Journal article (peer-reviewed)abstract
    • It has been demonstrated that prostate-specific antigen (PSA), in spite of its name, can be detected in body fluids and tumors from a variety of organs. Investigations have shown that human glandular kallikrein 2 (hK2), a related prostate-secreted protease, can activate the zymogen form of PSA, suggesting that the two enzymes might work as a functional unit, with hK2 as the activator molecule and PSA as the effector molecule. If this is true, then hK2 should be found together with PSA in body fluids other than seminal plasma, as well. Recently, a sensitive and specific assay was devised for hK2, enabling its measurement in picogram quantities. With this assay, the concentration of hK2 was determined in samples of seminal plasma, amniotic fluid, breast milk, and saliva. Simultaneously, the samples were assayed for molecular forms of PSA. In seminal plasma, the mean PSA concentration was 0.82 mg/ml, while the hK2 level was around two orders of magnitude lower: mean value, 6.4 microg/ml. Approximately the same ratio of PSA to hK2 as in seminal plasma was found in amniotic fluid and breast milk, but in most samples, the hK2 values were too low for direct measurements and had to be concentrated prior to analysis. Measurable levels of PSA, all in the free form, were detected in amniotic fluid at the thirteenth week of gestation and then gradually increased to levels around and over 1 microg/L from the twentieth week. Significant levels of PSA were detected in amniotic fluid collected at delivery, also. Measurable levels of mammary PSA were primarily detected in colostrum, with a range from less than 0.03 microg/L to 2.1 mg/L. Around half of the molecules were in complex with protease inhibitor. Most surprisingly, determinations on saliva samples showed that none of them had detectable PSA levels but had measurable concentrations of hK2 with a mean value, 0.09 microg/L. The presence in saliva suggests that hK2 can be the human equivalent to one of the mouse salivary kallikreins with important biological function, like the epidermal growth factor-binding protein or the gamma subunit of nerve growth factor. However, this was ruled out, as a phylogenetic analysis showed that the human and mouse glandular kallikreins evolved independently from a common precursor after the separation of the primate and rodent lineages. In conclusion, the measurements show that in addition to the previously known secretion in seminal plasma, hK2 is secreted in amniotic fluid, breast milk, and saliva. Furthermore, the concerted expression of PSA and hK2 in seminal plasma, amniotic fluid, and breast milk suggests that the two proteases might form a functional unit but not always as demonstrated by the sole presence of hK2 in saliva.
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  • Macías García, Beatriz, et al. (author)
  • The mitochondria of stallion spermatozoa are more sensitive than the plasmalemma to osmotic induced stress: role of c-Jun N-terminal Kinase (JNKs) pathway
  • 2012
  • In: Journal of Andrology. - Schaumburg, IL, United States : American Society of Andrology. - 0196-3635 .- 1939-4640. ; 33:1, s. 105-113
  • Journal article (peer-reviewed)abstract
    • Cryopreservation introduces extreme temperature and osmolality changes that impart lethal and sublethal effects on spermatozoa. Additionally, there is evidence that the osmotic stress induced by cryopreservation causes oxidative stress to spermatozoa. The main sources of reactive oxygen species in mammalian sperm are the mitochondria. In view of this, the aim of our study was to test whether or not osmotic stress was able to induce mitochondrial damage and to explore the osmotic tolerance of the mitochondria of stallion spermatozoa. Ejaculates from 7 stallions were subjected to osmolalities ranging from 75 to 1500 mOsm/kg, and the effect on sperm membrane integrity and mitochondrial membrane potential was studied. Additionally, the effects of changes in osmolality from hyposmotic to isosmotic and from hyperosmotic to isosmotic solutions were studied (osmotic excursions). The cellular volume of stallion spermatozoa under isosmotic conditions was 20.4 ± 0.33 μm3. When exposed to low osmolality, the stallion spermatozoa behaved like a linear osmometer, whereas exposure to high osmolalities up to 900 mOsm/kg resulted in decreased sperm volume. Although sperm membranes were relatively resistant to changes in osmolality, mitochondrial membrane potential decreased when osmolalities were low or very high (10.7 ± 1.74 and 16.5 ± 1.70 at 75 and 150 mOsm/kg, respectively, and 13.1 ± 1.83 at 1500 mOsm/kg), whereas in isosmolar controls the percentage of stallion sperm mitochondria with a high membrane potential was 41.1 ± 1.69 (P < .01). Osmotic excursions induced greater damage than exposure of spermatozoa to a given nonphysiologic osmolality, and again the mitochondria were more prone to damage induced by osmotic excursions than was the sperm plasma membrane. In search of intracellular components that could mediate these changes, we have detected for the first time the c-Jun N-terminal kinase 1/2 in stallion spermatozoa, which are apparently involved in the regulation of the viability of these cells.
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  • OHLSSON, KJELL, et al. (author)
  • Secretory Leucocyte Protease Inhibitor in the Male Genital Tract : PSA‐Induced Proteolytic Processing in Human Semen and Tissue Localization
  • 1995
  • In: Journal of Andrology. - 0196-3635. ; 16:1, s. 64-74
  • Journal article (peer-reviewed)abstract
    • ABSTRACT: Secretory leucocyte protease inhibitor, SLPI, is a low‐molecular‐weight, acid‐stable protein present in the liquid part of fresh human ejaculate but not demonstrable in the gel structure. No fragmentation of SLPI occurred during gel dissolution, but a slow proteolytic cleavage of SLPI was seen on incubation of the liquified semen at 37°C. The same pattern of degradation products was seen after incubation of SLPI with prostatic secretion and also with purified prostate‐specific antigen, PSA. We could identify Arg 20‐Tyr 21 and Met 73‐Leu 74 to be the primary cleavage sites upon proteolytic modification of SLPI by purified PSA. However, we did not find any inhibition of the enzymatic activity of PSA by SLPI, even at a 100‐fold molar excess of the inhibitor. The slow degradation of SLPI facilitated sampling and the reliable determination of the normal level of SLPI in seminal plasma, which was about 20 mg/L. We investigated the glandular origion of SLPI in the genital tract by immunocytochemistry. A strong immunostaining for SLPI was demonstrated in epithelial cells within the glandular lumina of the prostate gland, seminal vesicles, and epididymis but not in the stromal parts of these glands. In addition the immunostaining was also detected in the deferent ducts and the germinal epithelium of the testes. Taking into account that SLPI is a strong inhibitor of several proteases, including leukocyte elastase and cathepsin G, the results suggest that SLPI has a local protective function against proteolytic degradation of the male reproductive tract tissues during inflammation. 1995 American Society of Andrology
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  • Pena, FJ, et al. (author)
  • Identification of sperm morphometric subpopulations in two different portions of the boar ejaculate and its relation to postthaw quality
  • 2005
  • In: Journal of Andrology. - : American Society of Andrology. - 0196-3635 .- 1939-4640. ; 26:6, s. 716-723
  • Journal article (peer-reviewed)abstract
    • A statistical approach using sequentially principal component analysis (PCA), clustering, and discriminant analyses was. developed to identify sperm morphometric subpopulations in well-defined portions of the fresh boar ejaculate. Semen was obtained as 2 portions (the first 10 mL of the sperm-rich fraction and the rest of. the ejaculate, respectively) and frozen using a conventional protocol. Before freezing, an aliquot was Used for computer-assisted. sperm morphometry analysis (ASMA). Postthaw quality was evaluated using computer-assisted sperm analysis (CASA), and an annexin-V/PI assay evaluated sperm membranes. The PCA revealed that 3 variables represented more than 78% of the cumulative variance in sperm subpopulations. The clustering and discriminant analyses, based on 5780 individual spermatozoa, revealed the existence of 4 sperm subpopulations. The relative percentage of these subpopulations Varied between boar and ejaculate portions. Linear regression models based on measured morphometric characteristics could account for up to 36% of the percentage of intact sperm membranes postthaw. The ASMA protocol used in our study was useful to detect subtle morphometric differences between spermatozoa, and the combination of this analysis with a multivariate statistical procedure gave hew information on the biological characteristics of boar ejaculates that is not given by conventional sperm analysis.
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  • Sipilä, Petra, et al. (author)
  • Regional expression of androgen receptor coregulators and androgen action in the mouse epididymis.
  • 2011
  • In: Journal of andrology. - : Wiley. - 1939-4640 .- 0196-3635. ; 32:6, s. 711-7
  • Journal article (peer-reviewed)abstract
    • Endocrine regulation of the mouse initial segment (IS) and distal caput epididymides was studied using genome-wide profiling of gene expression. Among the IS-enriched genes, 29% were significantly down-regulated 1 day after gonadectomy. Of those genes, dihydrotestosterone (DHT) supplementation was not sufficient to maintain their pregonadectomy level of expression in 70%. Of the caput-enriched genes, 16% were significantly down-regulated after gonadectomy, and of those genes, DHT supplementation did not maintain the initial level of expression in 28%. Identical data were obtained by clustering analyses performed for the expression data of epididymal genes. Furthermore, the microarray data revealed that 26 androgen receptor coregulators were expressed in the epididymis, of which several were confirmed by quantitative reverse transcriptase polymerase chain reaction analysis. This suggests putative involvement of these proteins in the segment-specific regulation of the epididymal genes. The pattern of epididymal gene expression in the novel proximal epididymis-specific androgen receptor knockout mouse ProxE-ARKO, with severe hypotrophy and hypoplasia of the caput epithelium, furthermore suggested that a subset of genes whose expression cannot be maintained by systemic androgen alone still require either direct lumicrine androgen action or a permissive effect of circulating testosterone. It is evident that testicular factors, one of which could be the high-concentration luminal androgen, are important for the expression of IS-enriched genes, whereas the expression of distal caput-enriched genes is typically regulated by systemic androgens.
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28.
  • SZECSI, PAL B., et al. (author)
  • Gastricsin‐Mediated Proteolytic Degradation of Human Seminal Fluid Proteins at pH Levels Found in the Human Vagina
  • 1993
  • In: Journal of Andrology. - 0196-3635. ; 14:5, s. 351-358
  • Journal article (peer-reviewed)abstract
    • The proteolytic degradation of human seminal fluid proteins at acidic conditions has been investigated. Upon acidification to the pH level of the human vagina, autoproteolysis of most seminal fluid proteins occurred after 30 minute of incubation at 37°C. The degradation was unaffected by inhibitors of serine, thiol, or me‐tallo proteases, whereas pepstatin prevented any proteolysis. The proteins in seminal fluid depleted of the aspartic protease progastricsin did not degrade upon acidification. Readdition of the progastricsin restored the autoproteolytic ability of seminal fluid. Prostate‐specific antigen, prostatic acid phosphatase, and Zn‐α2‐glycoprotein are quickly degraded; albumin, transferrin, and lactoferrin are degraded more slowly. The low molecular weight fragments of semenogelin I and II and especially β‐microseminoprotein are somewhat resistant to proteolysis. These observations strongly suggest that the aspartic protease progastricsin is responsible for the autoproteolysis of seminal fluid proteins under acidic conditions. This suggests that the function of the enzyme is to degrade seminal fluid proteins deposited in the vagina; this in turn may decrease the antigenic load in the vagina and prevent immuno‐infertility. 1993 American Society of Andrology
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  • Udby, L, et al. (author)
  • Characterization and localization of cysteine-rich secretory protein 3 (CRISP-3) in the human male reproductive tract
  • 2005
  • In: Journal of Andrology. - : Wiley. - 0196-3635. ; 26:3, s. 333-342
  • Journal article (peer-reviewed)abstract
    • Mammalian members of the cysteine-rich secretory protein (CRISP) family are expressed predominantly in the male reproductive tract and are implicated in the process of reproduction from spermiogenesis, posttesticular sperm maturation, and capacitation to oocyte-sperm fusion, and possibly also penetration of the zona pellucida. Rodents express only 2 CRISPs (CRISP-1 and CRISP-2) in their male reproductive system, whereas humans and horses express an additional third member named CRISP-3. We have previously demonstrated that this protein is present in human seminal plasma as well as in other exocrine secretions, in blood plasma, and in neutrophilic granulocytes. To characterize the protein in seminal plasma and localize the production of CRISP-3 in the human male reproductive tract, we performed immunoblotting and enzyme-linked immunosorbent assay measurements of seminal plasma and immunohistochemistry and in situ hybridization of tissue specimens. We were able to show that human CRISP-3 is a quantitatively minor seminal plasma protein not associated with prostasomes. Furthermore, CRISP-3 expression was found in the secretory epithelium throughout the male genital tract, with particularly high expression in the cauda epididymis and ampulla vas deferens. Examination of seminal plasma from vasectomized males indicates that organs downstream of the epididymis are probably the major sources of seminal plasma CRISP-3.
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31.
  • Valtonen-André, Camilla, et al. (author)
  • Beta-microseminoprotein in serum correlates with the levels in seminal plasma of young, healthy males
  • 2008
  • In: Journal of Andrology. - : Wiley. - 0196-3635. ; 29:3, s. 330-337
  • Journal article (peer-reviewed)abstract
    • Beta-microseminoprotein (MSP) is one of the most abundant proteins secreted by the prostate gland. Because MSP is also synthesized in nonreproductive organs, the establishment of a solid relationship between the levels of MSP in serum and semen is crucial for future studies connecting MSP with aging or diseases of the prostate gland. We developed a specific, competitive, europium-based immunoassay to measure MSP in serum and seminal plasma. We also produced recombinant MSP in insect cells using baculo virus and purified it to homogeneity by a novel approach with ethanol extraction and gel filtration. The median values of MSP in 205 young men were 12 mu g/L (2.5-97.5 percentile, 4.9-26 mu g/L) in serum and 0.53 g/L (2.5-97.5 percentile, 0.13-2.0 g/L) or 1.8 mg (2.5-97.5 percentile, 0.32-6.6 mg) in seminal plasma. MSP in serum showed significant correlation to MSP in seminal plasma (r =.50, P <.001). Significant correlations were also found in seminal plasma between MSP and prostate-specific antigen (PSA) (r =.65, P <.001) and between MSP and Zn2+ (r =.54, P <.001). The yield of recombinant MSP in culture medium was 35 mg/L or higher, and recovery following ethanol extraction was 80%-90%. MSP in serum reflects the prostate secretion of MSP, and correlations were also found in seminal plasma between MSP and PSA and Zn2+. This suggests that MSP in serum can be used as a marker of prostate secretion, despite the contribution from extra prostatic tissues.
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