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1.
Mol Cell Endocrinol ; 267(1-2): 80-8, 2007 Mar 15.
Article in English | MEDLINE | ID: mdl-17292540

ABSTRACT

Members of the dual specificity tyrosine phosphorylated and regulated kinase family (Dyrk) were shown to have a highly testis-abundant or testis-restricted expression pattern. Furthermore, for some members of the family an involvement in gene expression regulation by phosphorylating transcription factors has been shown. Since little is known about the complex regulation of germ cell differentiation in spermatogenesis, we analysed the possible involvement of Dyrk kinases in this process. ISH experiments showed specific distribution of Dyrk kinases mainly in postmeiotic germ cell. We identified Dyrk4 as a testis-specific kinase with a very restricted expression to stage VIII postmeiotic spermatids. In vitro and in vivo experiments proved the enzymatic activity and suggested the cytoplasmatic localisation of Dyrk4. Finally, analysis of a Dyrk4 deficient mouse line showed that Dyrk4 is dispensable for male fertility, hence suggesting a functional redundancy of some Dyrk isoforms during spermiogenesis.


Subject(s)
Fertility/physiology , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Protein-Tyrosine Kinases/genetics , Protein-Tyrosine Kinases/metabolism , Spermatids/enzymology , Testis/enzymology , Animals , COS Cells , Chlorocebus aethiops , DNA, Complementary/genetics , Gene Expression Profiling , Gene Expression Regulation, Developmental , Gene Expression Regulation, Enzymologic , Humans , In Situ Hybridization , Isoenzymes/genetics , Isoenzymes/metabolism , Male , Mice , Protein Serine-Threonine Kinases/deficiency , Protein Transport , Protein-Tyrosine Kinases/deficiency , RNA, Messenger/genetics , RNA, Messenger/metabolism , Spermatids/cytology , Spermatogenesis , Testis/cytology , Dyrk Kinases
2.
Hum Reprod ; 22(3): 702-7, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17067996

ABSTRACT

BACKGROUND: In mice, administration of the glycosphingolipid biosynthesis inhibitor miglustat results in reversible infertility, characterized by impaired sperm motility and markedly abnormal sperm morphology. This observation suggested that miglustat might have utility for fertility control in man. To ascertain the impact of miglustat on human spermatogenesis, we conducted a pilot study of miglustat administration in normal men. METHODS: After a 2-week baseline period, seven normal men were administered miglustat 100 mg, orally, twice daily for 6 weeks. During treatment, subjects had frequent seminal fluid analyses to assess the impact of treatment on sperm concentration, motility and morphology and the ability to undergo the acrosome reaction by in vitro assays. RESULTS: Five subjects completed all aspects of the study. In these subjects, there was no apparent effect of miglustat on sperm concentration, motility or sperm morphology after 6 weeks of therapy. In addition, no changes in acrosome structure or function were observed with treatment, despite therapeutic concentrations of miglustat in the serum and seminal plasma. All subjects experienced gastrointestinal upset, diarrhoea and mild weight loss during treatment. No other abnormalities in blood counts, serum chemistries, vision or overall health were observed. CONCLUSION: In contrast to the observations in mice, the oral administration of miglustat does not appear to affect human spermatogenesis. Further elucidation of the mechanism underlying the species specificity of miglustat may improve our understanding of the role of glycosphingolipids in spermatogenesis and result in alternative approaches to male fertility control.


Subject(s)
1-Deoxynojirimycin/analogs & derivatives , Spermatogenesis/drug effects , 1-Deoxynojirimycin/adverse effects , 1-Deoxynojirimycin/blood , 1-Deoxynojirimycin/pharmacology , Acrosome Reaction/drug effects , Adult , Humans , Male , Pilot Projects , Semen/chemistry , Sperm Count , Sperm Motility/drug effects , Testosterone/blood
3.
Int J Androl ; 25(3): 168-74, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12031045

ABSTRACT

The antifertility action of (R,S)-alpha-chlorohydrin administered orally to male rats was compared with that of several novel chlorinated compounds known to inhibit glycolysis and the kinematics of rat sperm in vitro. Oral gavage of 1,6-dichloro-1,6-dideoxy-D-fructofuranose (dichlorodideoxyfructose, DCF), 1-chloro-3-hydroxypropanone, its dimethylketal and bromopyruvate did not reduce the fertility of male rats below that of controls at the equivalent antifertility dose of (R,S)-alpha-chlorohydrin (5 mg/kg/day) or higher. As anticipated for a compound cleaved to products of (S)-chirality even high doses of DCF (200 mg/kg) showed no effect on renal function. 36Cl-Labelled DCF administered orally to male rats was eliminated only slowly in the urine (16% of the ingested dose excreted in 96 h). In the first 8 h, approximately 50% of DCF was excreted unchanged, 30% was excreted as 3-chlorolactate (BCLA), the oxidation product 3-chlorolactaldehyde and 25% as Cl-. By 24 h little DCF remained and the major metabolite (70%) was BCLA and 20% Cl-. The high rate of dechlorination is most likely responsible for the low antifertility action of DCF.


Subject(s)
Deoxy Sugars/pharmacology , Fertility/drug effects , Fructose/pharmacology , Acetone/analogs & derivatives , Acetone/chemistry , Acetone/pharmacology , Animals , Contraceptive Agents, Male/pharmacology , Deoxy Sugars/chemistry , Deoxy Sugars/toxicity , Fructose/analogs & derivatives , Fructose/chemistry , Fructose/toxicity , Kidney Tubules/drug effects , Kidney Tubules/metabolism , Male , Methylation , Pyruvates/pharmacology , Rats , Rats, Wistar , alpha-Chlorohydrin/pharmacology
4.
Int J Androl ; 25(2): 94-9, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11903658

ABSTRACT

(R,S)-Ornidazole, an effective antifertility agent for male rats at 400 mg/kg/day, was ineffective at this dose in male mice and at 1000 mg/kg/day caused neural effects. The compound was not excreted unchanged and more polar metabolites and Cl- were detected in 0-8 h urine following a single injection (400 mg/kg). In 8-24 h urine even these metabolites and most Cl ion were absent, indicating rapid metabolism of ornidazole. There was no organ specific accumulation of 36Cl-(R,S)-ornidazole in murine tissues. After injection of 36Cl-(R,S)-alpha-chlorohydrin, another antifertility agent in the rat but not the mouse, there was also no tissue-specific accumulation of radioactivity in the reproductive tract of either species. Urinary excretion rates of alpha-chlorohydrin were twice as rapid in mice as in rats. In mice, alpha-chlorohydrin was the major urinary metabolite, but in the rat metabolites included Cl-, 3-chlorolactate (BCLA) at 5 and 10 h and BCLA only at 24 h. BCLA was the major metabolite detected in most tissues at 10 and 24 h. In the rat cauda (but not caput) epididymidis the glycolytic inhibitor 3-chlorolactaldehyde was present at 5 h (but not 10 h), indicative of early metabolism. These results demonstrate a greater metabolism and excretion of putative antifertility agents in the mouse than the rat, lowering the amount of effective inhibitor circulating in the animal, which may explain why (R,S)-alpha-chlorohydrin and (R,S)-ornidazole are ineffective in this species at the dosages and injection times used, despite their spermatozoa being sensitive to inhibition by (R,S)-alpha-chlorohydrin in vitro.


Subject(s)
Chlorine , Chlorohydrins/pharmacokinetics , Fertility/physiology , Ornidazole/analogs & derivatives , Ornidazole/pharmacology , Ornidazole/pharmacokinetics , Amebicides/pharmacology , Animals , Biotransformation , Chlorohydrins/urine , Female , Fertility/drug effects , Male , Metabolic Clearance Rate , Mice , Mice, Inbred Strains , Ornidazole/urine , Radioisotopes , Rats , Tissue Distribution
5.
J Androl ; 22(3): 464-70, 2001.
Article in English | MEDLINE | ID: mdl-11330647

ABSTRACT

Nonhormonal contraceptives that act by blocking energy metabolism within sperm have the advantage over spermatogenic inhibitors by their fast onset of infertility and their almost immediate restoration of fertility after withdrawal of the contraceptive agent. This study was done to test new chlorinated compounds for their contraceptive potency on rodent and human sperm in vitro. Cells were incubated in a medium containing glucose as the sole energy source with 1-chloro-3-hydroxypropanone (CHOP) and 1,6-dichloro-1,6-dideoxy-D-fructose (DCDF), chlorinated analogues of glycolytic substrates, as well as racemic (R,S)-alpha-chlorohydrin (ACH). After incubation, enzymatic activity and kinematic parameters were estimated. A dose-dependent inhibition of the glycolytic enzyme, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), of rat and mouse distal cauda epididymidal and human ejaculated sperm by ACH, CHOP, and DCDF was demonstrated. Triosephosphate isomerase (TPI) was inhibited by ACH, but not by CHOP and DCDF, irrespective of species. All compounds inhibited sperm motility and kinematic parameters with increasing concentration. The results confirm that inhibition of glycolytic enzymes of sperm, including those of human, can be effectively brought about by a variety of chloro-compounds that can be converted to (S)-3-chlorolactaldehyde, the stereospecific chloro-derivative of the enzyme's natural substrate, (R)-glyceraldehyde 3-phosphate, and could be developed into contraceptive agents for men.


Subject(s)
Acetone/pharmacology , Chemosterilants/pharmacology , Deoxy Sugars/pharmacology , Enzymes/metabolism , Fructose/pharmacology , Glycolysis/physiology , Sperm Motility/drug effects , alpha-Chlorohydrin/pharmacology , Acetone/analogs & derivatives , Animals , Drug Resistance , Fructose/analogs & derivatives , Humans , In Vitro Techniques , Male , Mice , Mice, Inbred Strains , Rats , Rats, Sprague-Dawley
6.
Int J Androl ; 23(5): 284-93, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11012786

ABSTRACT

Chlorinated antifertility compounds are known to inhibit glycolysis of spermatozoa as they reside in the epididymis but new compounds need to be evaluated that retain antifertility action but do not exhibit side-effects. In this study, two known antifertility agents and a related compound were compared for their inhibition of rat sperm metabolism and motility in vitro. The dose-dependent inhibition in vitro of the glycolytic enzymes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and triosephosphate isomerase (TPI) of distal cauda epididymal rat spermatozoa by (R)-, (S)- and (R,S)-ornidazole (ORN), (R,S)-alpha-chlorohydrin (ACH) and 1-chloro-3-hydroxypropanone (CHOP) was compared. The direct inhibition of GAPDH by ORN suggests that it inhibits without prior conversion outside the cell but inhibition was not stereo-specific. The GAPDH, but not TPI, activity of spermatozoa incubated with ACH and CHOP was highly correlated with kinematic parameters of spermatozoa incubated in pyruvate- and lactate-free medium. ACH only inhibited the activity of intact spermatozoa and the inhibition was not reversed by washing the particulate sperm fraction after sonication. High concentrations of ACH (100 mmol/L) killed intact rat spermatozoa and decreased the extent of GAPDH inhibition. CHOP, unlike ACH, was an effective inhibitor of both intact and sonicated cells. Pre-CHOP, the dimethylketal precursor of CHOP, and its other hydrolysis product MeOH, were both ineffective in vitro. CHOP and related ketals may be more effective inhibitors of sperm glycolysis than ACH and may prove useful for investigating sperm-specific glycolytic inhibition, a prerequisite for the development of antiglycolytic, post-testicular acting contraceptives.


Subject(s)
Acetone/analogs & derivatives , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Ornidazole/pharmacology , Spermatozoa/drug effects , Triose-Phosphate Isomerase/metabolism , alpha-Chlorohydrin/pharmacology , Acetone/pharmacology , Animals , Cells, Cultured , Epididymis/cytology , Male , Rats , Sonication , Sperm Motility/drug effects , Spermatozoa/enzymology , Spermatozoa/physiology
7.
J Reprod Fertil ; 118(1): 127-35, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10793634

ABSTRACT

The effects of the male antifertility agent ornidazole on glycolysis as a prerequisite for fertilization were investigated in rats. Antifertility doses of ornidazole inhibited glycolysis within mature spermatozoa as determined from the lack of glucose utilization, reduced acidosis under anaerobic conditions and reduced glycolytic enzyme activity. As a consequence, cauda epididymidal spermatozoa from ornidazole-fed rats were unable to fertilize rat oocytes in vitro, with or without cumulus cells, which was not due to transfer of an inhibitor in epididymal fluid with the spermatozoa. Under IVF conditions, binding to the zona pellucida was reduced in spermatozoa from ornidazole-fed males and the spermatozoa did not undergo a change in swimming pattern, which was observed in controls. The block to fertilization could be explained by the disruption of glycolysis-dependent events, since reduced binding to the zona pellucida and a lack of kinematic changes were demonstrated by control spermatozoa in glucose-free media in the presence of respiratory substrates. The importance of glycolysis for binding to, and penetration of, the zona pellucida, and hyperactivation in rats is discussed in relation to the glycolytic production of ATP in the principal piece in which local deprivation of energy may explain the reduced force of spermatozoa from ornidazole-fed males.


Subject(s)
Fertility/drug effects , Ornidazole/pharmacology , Sperm Motility/drug effects , Sperm-Ovum Interactions/drug effects , Spermatozoa/metabolism , Analysis of Variance , Animals , Depression, Chemical , Female , Fertilization in Vitro , Glycolysis/drug effects , Magnetic Resonance Spectroscopy , Male , Rats , Rats, Sprague-Dawley , Spermatozoa/drug effects , Zona Pellucida/metabolism
8.
Clin Infect Dis ; 25(5): 1205-10, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9402382

ABSTRACT

Relapse after apparently successful treatment of coccidioidomycosis has been a problem with both amphotericin B and the azoles. We conducted a retrospective cohort study of 34 patients who required therapy for coccidioidomycosis between 1973 and 1993; 10 relapsed and 25 (one patient received two courses of therapy) did not relapse during follow-up. The mean time to relapse after completion of therapy was 7.3 months (range, 1-21 months). All 34 patients responded clinically to therapy. A fourfold or greater decrease in titers of antibody, as determined by complement fixation (CF), during therapy was seen in seven (78%) of nine patients who relapsed and 17 (85%) of 20 patients who did not relapse (P = .956). There was no significant difference between relapsers and nonrelapsers in terms of the lowest CF titer during therapy, the CF titer at the end of therapy, or the peak CF titer. The risk of relapse was increased among those with a peak CF titer of > or = 1:256 (relative risk [RR] = 4.7; 95% confidence interval [CI] = 1.4-16.1), as compared with patients who did not mount such a high antibody response. Similarly, the risk of relapse was higher among those with serially negative coccidioidin skin tests (CSTs) than those with serially positive CSTs (RR = 4.8; 95% CI = 1.2-19.5). We conclude that clinical response, lowest CF titer, end-of-therapy CF titer, and decrease in the CF titer of at least fourfold are not predictive of relapse in patients with coccidioidomycosis. Negative serial coccidioidin skin tests and a peak CF antibody titer of > or = 1:256 are independently associated with increased risk of relapse.


Subject(s)
Coccidioidomycosis/physiopathology , Adolescent , Adult , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Coccidioidomycosis/drug therapy , Cohort Studies , Female , Fluconazole/therapeutic use , Follow-Up Studies , Humans , Ketoconazole/therapeutic use , Male , Middle Aged , Predictive Value of Tests , Recurrence , Retrospective Studies
10.
Int J Androl ; 20(6): 347-55, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9568527

ABSTRACT

Ornidazole, a 5-nitro-imidazole derivative, has contraceptive properties in rats. As some ornidazole passes through the body unmetabolized after administration, the aim of this study was to investigate if ornidazole itself has a direct effect on sperm motility and whether these effects are limited or potentiated by the epididymal epithelium or structural changes to the molecule. Cauda epididymal spermatozoa or cauda epididymal tubules were incubated with ornidazole or ornidazole analogues, and motility parameters were subsequently measured by means of a computer-assisted sperm analysis (CASA) system. Incubation of spermatozoa in 2.5 mmol/L ornidazole for 4 h reduced their motility significantly, whereas incubation of epididymal tubules for 8 h in 10 mmol/L ornidazole was required to alter the velocity parameters of the enclosed spermatozoa upon release, suggesting that extratubular non-metabolized ornidazole can participate in inhibiting the motility in vivo. The in vitro toxicity of ornidazole derivatives depends on the halogen present and on the position of the nitro-group. The putatively inactive (R)- and the active (S)-ornidazole exhibited equivalent depression of sperm motility by direct incubation. This observation, and the differences between the in vitro and the in vivo efficacies of various ornidazole analogues, indicates distinct mechanisms of motility inhibition in the two experimental systems.


Subject(s)
Contraceptive Agents, Male/toxicity , Ornidazole/toxicity , Sperm Motility/drug effects , Spermatozoa/drug effects , Animals , Male , Ornidazole/analogs & derivatives , Rats , Rats, Sprague-Dawley , Spermatozoa/physiology , Stereoisomerism
12.
Mil Med ; 160(6): 304-8, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7659230

ABSTRACT

Beginning in 1991, case reports of coccidioidomycosis in California increased dramatically, pursuant to a variety of natural and demographic factors. This highly infectious fungal disease with propensity to disseminate widely, mimic other conditions, and cause pathology at locations distant in place and time is readily treatable if recognized at an early stage. The concentration of military bases in endemic areas and the mobility of military personnel suggest a heightened potential for case presentations elsewhere and a need for elevated diagnostic suspicion on the part of military physicians worldwide. We review three cases of disseminated disease recently referred to our facility.


Subject(s)
Coccidioidomycosis/epidemiology , Disease Outbreaks , Military Personnel , Adult , Anti-Bacterial Agents/therapeutic use , California/epidemiology , Coccidioides/isolation & purification , Coccidioidomycosis/diagnosis , Coccidioidomycosis/drug therapy , Humans , Male
15.
Anal Biochem ; 155(1): 168-76, 1986 May 15.
Article in English | MEDLINE | ID: mdl-3717553

ABSTRACT

Negative ion fast atom bombardment mass spectrometry (NI-FAB/MS) was employed to characterize the fatty acids esterified to the lipid A backbone of lipopolysaccharides (LPS) of gram-negative bacteria. LPS and their chemically derived lipid A produced readily detectable fragment ions characteristic of fatty acids. The NI-FAB/MS method is specific, yielding ions indicative of ester- but not of amide-bound fatty acids. The mass spectra of Enterobacteriaceae LPS revealed the presence of lauric (m/z 199), myristic (m/z 227), palmitic (m/z 255), and 3-hydroxymyristic (m/z 243) acids. Pseudomonas aeruginosa LPS gave distinctive fragment ions indicative of 3-hydroxydecanoic (m/z 187), lauric, and 2-hydroxylauric (m/z 215) acids. The Neisseria gonorrhoeae LPS could be distinguished from the others due to the presence of ester-linked 3-hydroxylauric acid. All of the LPS gave abundant ions of m/z 177 and 159, which were derived from diphosphoryl substituents. The use of NI-FAB/MS thus allowed rapid identification of lipid A esterified fatty acids without chemical derivatization or gas chromatographic analysis.


Subject(s)
Endotoxins/analysis , Fatty Acids/analysis , Lipopolysaccharides/analysis , Amides/analysis , Chromatography, Gas , Esters/analysis , Gram-Negative Bacteria/analysis , Lipid A/analysis , Mass Spectrometry/methods
20.
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