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1.
Reprod Biol Endocrinol ; 18(1): 96, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32998760

RESUMO

BACKGROUND: Despite significant advances in contraceptive options for women, vasectomy and condoms are the only options available for male contraception. Due to this limitation, the burden of contraception resides on the shoulders of females only. Therefore, there is an urgent need to develop a safe, effective and reversible method of contraception for men. Amongst the alternative approaches, microbial derived products are gaining attention of the scientific world to combat unintended pregnancies. Earlier in our laboratory, sperm impairing microbial factor (Sperm immobilization factor) isolated from Staphylococcus aureus has shown excellent contraceptive efficacy in female mice. Keeping this in mind, the present study was carried out to exploit the sperm immobilization factor (SIF) as potential male contraceptive using vas deferens for administration in mouse model. METHODS: SIF (10, 50, 100 or 200 µg) was inoculated in the lumen of right vas deferens whereas the left vas deferens served as control. The mice were sacrificed at Day 3, 7, 14, 21, 30, 45, 60 and 90 after inoculation and the results in terms of change in body weight, seminal parameters, Tissue somatic indices (TSI), haematological parameters, serum level of testosterone, lipid peroxidation and histology were studied. In order to ratify the SIF induced azoospermia SIF (200 µg) was administered with different doses viz. 100, 200, 300, 400 or 500 µg of SIF binding receptor extracted from mouse spermatozoa. RESULTS: The weight profile studies of all the experimental groups showed no significant change in the initial and final body weight. In case of seminal parameters, the results revealed that right vas deferens treated with SIF showed azoospermia and with 200 µg of SIF it persisted up to 90 days. TSI of reproductive organs and non-reproductive organs showed no significant change in all the experimental groups. The haematological indices were found to be unaltered throughout the course of investigation however significant decrease in testosterone level was observed in the treated mice. The treatment also affected the oxidative status of the testis. Further, histological studies revealed hypospermatogenesis and late maturation arrest on treated side whereas the left side which served as control showed normal tissue histology. SIF induced azoospermia was ameliorated when administered with 400 µg of SIF binding receptor from mouse spermatozoa. CONCLUSION: SIF, when administered via intra vas deferens route, could lead to complete azoospermia. Therefore, it could be considered as a potential male contraceptive.


Assuntos
Anticoncepcionais Masculinos , Imobilizantes dos Espermatozoides/isolamento & purificação , Imobilizantes dos Espermatozoides/farmacologia , Staphylococcus aureus/química , Animais , Anticoncepção/métodos , Anticoncepcionais Masculinos/isolamento & purificação , Anticoncepcionais Masculinos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/citologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia
2.
Microb Pathog ; 128: 55-62, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30583018

RESUMO

The present study was undertaken to demonstrate the existence of mimicry between spermatozoa and bacteria. For this, the shared antigenic determinants between mouse spermatozoa and Streptococcus pyogenes against a common ligand, sperm immobilization factor (SIF), were isolated. The mimicry was established on the basis of their ability to ameliorate the SIF-mediated compromised sperm parameters in vitro viz. motility, viability, morphology and Mg2+-ATPase activity of spermatozoa. Further, both the receptors i.e. SIF-binding receptor from mouse spermatozoa (MS-SBR) and SIF-binding receptor from S. pyogenes (S-SBR) were able to block the binding of FITC-labelled SIF to spermatozoa and bacteria. The in vivo studies also showed that MS-SBR (10 µg)/S-SBR (25 µg) could alleviate SIF-induced infertility in female BALB/c mice, further providing evidence for molecular similarities between bacteria and spermatozoa.


Assuntos
Antídotos/metabolismo , Infertilidade , Receptores de Superfície Celular/efeitos dos fármacos , Imobilizantes dos Espermatozoides/farmacologia , Espermatozoides/efeitos dos fármacos , Streptococcus pyogenes/metabolismo , Animais , ATPase de Ca(2+) e Mg(2+)/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mimetismo Molecular , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/citologia , Staphylococcus aureus/metabolismo
3.
Reprod Fertil Dev ; 31(3): 602-612, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30517837

RESUMO

A strain of Staphylococcus aureus, capable of invitro immobilisation of human and mouse spermatozoa, was already present in our laboratory. Therefore, in the present study, the factor responsible (sperm immobilisation factor, SIF) was isolated and purified. It was found to compromise not only motility, but also viability, morphology and Mg2+-ATPase activity of mouse spermatozoa. Also, SIF (250µgmL-1), when administered intravaginally in female BALB/c mice before mating, showed 100% contraceptive effect. Moreover, fluorescein isothiocyanate-labelled SIF was also found to bind mouse spermatozoa and various motile as well as non-motile bacteria, indicating the presence of common SIF-binding receptors on spermatozoa and bacteria. Further, to demonstrate molecular mimicry, the amelioration of SIF-induced impairment of sperm function by a SIF-binding bacterial receptor was compelling. For this, the SIF-binding receptor from Escherichia coli (E-SBR) was purified and evaluated for its ameliorative effect on SIF-induced sperm impairment invitro and invivo. Interestingly, upon the addition of mouse spermatozoa to SIF pre-incubated with E-SBR, an ameliorative effect against SIF-induced impairment of sperm function could be observed through analysis of normal sperm parameters (motility, viability, morphology, Mg2+-dependent ATPase levels). E-SBR also blocked binding of labelled SIF to spermatozoa and bacteria and alleviated SIF-induced infertility in female BALB/c mice. This provided evidence for molecular similarities between bacteria and spermatozoa, owing to which anti-bacterial antibodies cross-reacting with spermatozoa might be produced and infertility might follow.


Assuntos
Imobilizantes dos Espermatozoides/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Animais , ATPase de Ca(2+) e Mg(2+)/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Espermatozoides/metabolismo
4.
Org Biomol Chem ; 12(19): 3090-9, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24705515

RESUMO

1-Substituted piperazinecarbodithioates were obtained by an unusual removal of CS2 in benzyl substituted dithiocarbamate derivatives under acid and basic conditions during design and synthesis of 1,4-(disubstituted)piperazinedicarbodithioates as double edged spermicides. A plausible mechanism for CS2 removal has been proposed. All synthesized compounds were subjected to spermicidal, antitrichomonal and antifungal activities. Twenty-one compounds irreversibly immobilized 100% sperm (MEC, 0.06-31.6 mM) while seven compounds exhibited multiple activities. Benzyl 4-(2-(piperidin-1-yl)ethyl) piperazine-1-(carbodithioate) (18) and 1-benzyl 4-(2-(piperidin-1-yl)ethyl)piperazine-1,4-bis(carbodithioate) (24) exhibited appreciable spermicidal (MEC, 0.07 and 0.06 mM), antifungal (MIC, 0.069-0.14 and >0.11 mM) and antitrichomonal (MIC, 1.38 and 0.14 mM) activities. The probable mode of action of these compounds seems to be through sulfhydryl binding which was confirmed by fluorescence labeling of sperm thiols.


Assuntos
Desenho de Fármacos , Piperazinas/química , Piperazinas/síntese química , Imobilizantes dos Espermatozoides/química , Imobilizantes dos Espermatozoides/síntese química , Tiocarbamatos/química , Tiocarbamatos/síntese química , Antifúngicos/síntese química , Antifúngicos/farmacologia , Morte Celular/efeitos dos fármacos , Corantes Fluorescentes/metabolismo , Células HeLa , Humanos , Lactobacillus/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Piperazinas/farmacologia , Imobilizantes dos Espermatozoides/farmacologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Relação Estrutura-Atividade , Compostos de Sulfidrila/metabolismo , Tiocarbamatos/farmacologia , Trichomonas/efeitos dos fármacos
5.
Andrologia ; 44(6): 381-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22486240

RESUMO

Previous study conducted in our department showed that 50% ethanolic extract of the root of Ricinus communis possess reversible antifertility effect and a 62-kDa protein (Rp) from this extract is responsible for the antifertility effects. In this study, we compared the spermicidal effect of this Rp with nonoxynol-9 (N-9) in vitro. The sperm immobilisation studies showed that 100 µg ml(-1) of Rp was able to immobilise the sperms completely within 30 s. Sperm revival test revealed that the spermicidal effect was irreversible. There was also a significant reduction in sperm viability and hypo-osmotic swelling in Rp and N-9 treated groups in comparison with the control. In Rp and N-9 treated groups, the number of acrosome-reacted cells was found to be high and also caused agglutination of the spermatozoa, indicating the loss of intactness of the plasma membrane, which was further supported by the significant reduction in the activity of membrane bound 5'-nucleotidase, acrosomal acrosin. In short, the protein Rp possesses spermicidal activity in vitro and its effects are similar to that of nonoxynol 9.


Assuntos
Nonoxinol/farmacologia , Proteínas de Plantas/farmacologia , Ricinus/química , Imobilizantes dos Espermatozoides/farmacologia , 5'-Nucleotidase/metabolismo , Acrosina/metabolismo , Reação Acrossômica/efeitos dos fármacos , Animais , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Masculino , Peso Molecular , Proteínas de Plantas/química , Proteínas de Plantas/toxicidade , Ratos , Ratos Sprague-Dawley , Aglutinação Espermática/efeitos dos fármacos , Imobilizantes dos Espermatozoides/química , Imobilizantes dos Espermatozoides/toxicidade , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/citologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia
6.
Can J Microbiol ; 55(7): 874-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19767860

RESUMO

Staphylococcus aureus isolated from the cervix of an infertile woman was found to cause complete immobilization of human spermatozoa in vitro. Only the cell culture and cell-free supernatant showed immobilization activity, indicating that the sperm immobilization factor might be released extracellularly by the organism because no activity was observed with the washed cells. Heat treatment of the supernatant at 60 degrees C for 10 min waived its immobilizing activity, indicating that the active component may be a protein. The bioactive molecule from the supernatant was purified to homogeneity by ammonium sulfate precipitation, gel permeation chromatography, and ion exchange chromatography. Sperm immobilization factor (SIF) was found to be an approximately 20 kDa protein. SIF at a concentration of 10 microg/mL was required to cause 100% immobilization of human spermatozoa after 30 min of incubation at 37 degrees C, whereas a concentration of 150 microg/mL caused immediate immobilization, and a concentration of 200 microg/mL resulted in instant loss of viability of human spermatozoa, observed by eosin-nigrosin staining. Scanning electron microscopy showed that the treatment of human spermatozoa with SIF caused multiple defects in the head, midpiece, neck, and tail region of human spermatozoa.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Imobilizantes dos Espermatozoides/isolamento & purificação , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Staphylococcus aureus/química , Proteínas de Bactérias/química , Proteínas de Bactérias/farmacologia , Humanos , Masculino , Peso Molecular , Imobilizantes dos Espermatozoides/química , Imobilizantes dos Espermatozoides/farmacologia , Espermatozoides/fisiologia
7.
J Coll Physicians Surg Pak ; 19(8): 510-3, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19651015

RESUMO

OBJECTIVE: To determine the effects of lead and zinc administration on the quality of semen of albino rats. STUDY DESIGN: Experimental study. PLACE AND DURATION OF STUDY: Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi, from August 2003 to December 2005. METHODOLOGY: Sixty adult albino rats selected for the study were divided into three groups, group A received injection normal saline 1 ml intraperitoneally daily for 8 weeks. Group B received lead chloride in a dose of 10 mg/kg body weight intraperitoneally daily. Group C received lead chloride in a dose of 10 mg/kg body weight and zinc chloride in a dose of 1 mg/kg body weight intraperitoneally daily. On the day of completion of treatment, the animals were sacrificed; epididymis was used for semen analysis. Student's t-test was used to determinate significance; the p-value < 0.05 was taken as significant. RESULTS: The number of sperms was 7.3, 1.7 and 6.6 million cells/ml in groups A, B and C respectively. Sperm's count decreased by 87% in group B (p < 0.001, CI 4117082.4 - 6965747.6) as compared to group A. Compared with group C, the sperm's count was decreased to 75% (p < 0.001, CI -5417413 to -4416987). The immotility of sperms was 27%, 57% and 26% in groups A, B and C respectively. There was 30% decreased motility of sperm in group B (p < 0.001, CI -30.19425 to -19.80575) as compared to group A. Compared with group C, the immotile sperm were increased to 31% (p < 0.001, CI 19.87494 - 30.92506). CONCLUSION: Lead produced toxic effects on germinal epithelium and altered the quality of semen which was improved by zinc.


Assuntos
Cloretos/farmacologia , Chumbo/toxicidade , Sêmen/efeitos dos fármacos , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Compostos de Zinco/farmacologia , Animais , Epididimo/citologia , Epididimo/efeitos dos fármacos , Injeções Intraperitoneais , Masculino , Ratos , Sêmen/citologia , Imobilizantes dos Espermatozoides/efeitos adversos , Imobilizantes dos Espermatozoides/farmacologia
8.
J Ethnopharmacol ; 115(1): 36-41, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-18029123

RESUMO

AIM OF THE STUDY: Contraceptive plants which were introduced by folk in traditional remedies are investigated worldwide. In this study, the contraceptive effects of Ruta graveolens L., which has been mentioned for male contraceptive in Iranian traditional folk medicine, was experimented on human sperm. MATERIALS AND METHODS: Different doses of lyophilized aqueous extract of Ruta graveolens L. were added to an amount of fresh semen, containing 10(6) cells in a 1:1 volumic ratio. Motility and viability of cells, DNA status, mitochondrial activity and sperm revival tests were carried out. RESULTS: The sperm immobilization effects of the extract appeared immediately in a does-dependent manner and 100% of the sperms became immotile at a concentration of 100mg/ml but other parameters were intact. After washing the sperms, motility was returned in 30.8+/-3.2% of the sperms, besides coiled tails in 38.6+/-5.5% of the treated cells, in comparison to 12.5+/-2.0% of the control group (p=0.001). The part of the extract, responsible for immobilization of the sperms was stable upon boiling. CONCLUSIONS: As the cells were alive and immotile, probably some ionic currents are blocked by a thermostable component of the plant which can be promising as a new male channel blocker contraceptive.


Assuntos
Extratos Vegetais/farmacologia , Ruta/química , Imobilizantes dos Espermatozoides/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Anticoncepcionais Masculinos , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Irã (Geográfico) , Masculino , Medicina Tradicional , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Bloqueadores dos Canais de Potássio/administração & dosagem , Bloqueadores dos Canais de Potássio/isolamento & purificação , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/metabolismo , Imobilizantes dos Espermatozoides/administração & dosagem , Imobilizantes dos Espermatozoides/isolamento & purificação , Espermatozoides/efeitos dos fármacos
9.
Eur J Pharm Sci ; 81: 67-74, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26455286

RESUMO

Sexually active women often seek protection against unplanned pregnancies. Latter can be effectively controlled by consistent use of spermicides during each coital act. However, side effects associated with the use of available synthetic spermicidal agents have directed the interest towards identifying newer and safer agents. Present studies were undertaken to formulate a vaginal contraceptive gel, containing sperm immobilizing factor (SIF) isolated from Staphylococcus aureus using 1% w/v Carbopol. SIF loaded gel formulation was characterized for various in vitro parameters i.e. pH, spreadability, texture profiling, rheological properties, and in vitro release studies. The prepared formulation was found to possess significant spreading properties, gel firmness and strength, and released about 80% of SIF within 30min. Latter can completely immobilize human spermatozoa within 20s, at a dose of 200µg/ml. SIF in the proposed gel formulation showed 100% contraceptive effect when used at amount as low as of 10µg, thus confirming the possibility to develop it as a potent vaginal contraceptive for future use.


Assuntos
Fertilidade/efeitos dos fármacos , Imobilizantes dos Espermatozoides/administração & dosagem , Espermatozoides/efeitos dos fármacos , Resinas Acrílicas/química , Animais , Liberação Controlada de Fármacos , Feminino , Humanos , Masculino , Camundongos Endogâmicos BALB C , Reologia , Imobilizantes dos Espermatozoides/química , Imobilizantes dos Espermatozoides/farmacologia , Espermatozoides/fisiologia , Staphylococcus aureus , Cremes, Espumas e Géis Vaginais/administração & dosagem , Cremes, Espumas e Géis Vaginais/química , Cremes, Espumas e Géis Vaginais/farmacologia
10.
Fertil Steril ; 76(1): 157-62, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11438336

RESUMO

OBJECTIVE: To identify prospective oxidants that rapidly immobilize human sperm upon contact with human semen. DESIGN: Inorganic, organic, and enzymatically-generated oxidants were mixed with human semen and spermicidal activity was tracked by a modified Sander-Cramer assay. SETTING: Commercial and university-based laboratories. PATIENT(S): Semen samples obtained through a university-based andrology laboratory. INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Quantitation of spermicidal activity of test oxidants. RESULT(S): Sperm lost motility within 20 seconds of exposure to enzymatically generated free iodine (I(2)). Toluidine blue, phenazine methosulfate, or methylene blue exhibited some, albeit much less, spermicidal activity. Oxidants formed by mixing ascorbic acid with Fe(III)-EDTA, xanthine with xanthine oxidase, or by exposing sperm to the nitric oxide generator, SIN-1 (3-morpholinosydnonimine hydrochloride), were far less potent spermicidal agents. CONCLUSION(S): Free I(2) formed in situ and presented to semen is an extremely potent spermicide. Additional studies on methods of generating de novo I(2) may be beneficial in developing a novel new class of nondetergent-based spermicides.


Assuntos
Oxidantes/farmacologia , Imobilizantes dos Espermatozoides/farmacologia , Espermicidas/farmacologia , Espermatozoides/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Iodo/farmacologia , Masculino , Motilidade dos Espermatozoides/efeitos dos fármacos
11.
J Androl ; 16(4): 334-41, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8537251

RESUMO

Studies of protection of testicular function from cyclophosphamide with hormonal pretreatment have been limited by the lack of a convenient model for cyclophosphamide-induced inactivation of stem spermatogonia. In the rat, the mortality from cyclophosphamide had prevented the administration of sufficient dosages to produce detectible damage to stem spermatogonia. To overcome this problem, we used bone marrow transplantation and sodium 2-mercaptoethanesulfonate (Mesna) treatment to raise the lethal dose for 50% of the animals (LD50) for cyclophosphamide from 275 to > 400 mg/kg body weight. In addition we used irradiation, 2 weeks prior to injection of cyclophosphamide, to greatly enhance the measured toxicity of cyclophosphamide towards stem spermatogonia. Whereas sperm counts at 9 weeks after a 300 mg/kg cyclophosphamide dose were reduced by only a factor of 1.6 without prior irradiation, they were reduced by a factor of 60 when 2.5 Gy of irradiation had been given. Dramatic protection against this toxicity was produced by hormone treatment with a gonadotropin-releasing hormone (GnRH) antagonist (Nal-Glu) and an antiandrogen (flutamide) following the radiation but prior to cyclophosphamide. This hormone treatment did not modify the stem cell toxicity of the radiation and it therefore must be protecting stem cells against cyclophosphamide-induced damage. Because GnRH antagonist-antiandrogen treatment can protect stem spermatogonial survival and/or function in the rat from cyclophosphamide-induced damage, if the same principles are applicable in human, hormonal pretreatment should be useful for preventing the prolonged azoospermia caused by chemotherapy with cyclophosphamide-containing protocols.


Assuntos
Antagonistas de Androgênios/farmacologia , Ciclofosfamida/antagonistas & inibidores , Flutamida/farmacologia , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Espermatozoides/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/análogos & derivados , Humanos , Masculino , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Imobilizantes dos Espermatozoides/farmacologia , Espermatozoides/citologia
12.
Reprod Toxicol ; 16(1): 57-64, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11934532

RESUMO

We examined the potential toxicity of pentavalent organic arsenicals for human sperm. We used computer-assisted sperm analysis to examine the effects of three aminophenyl arsenicals and their nine N-substituted quinazoline, pyrimidine, and purine derivatives on human sperm motility and kinematics in human semen and medium. Among the arsenicals examined, (aminophenylazo)-phenyl arsonic acid and its N-substituted pyrimidine derivative PHI-370 (2-methylthio-4-[(4'-aminophenylazo)-phenylarsonic acid] pyrimidine) exhibited rapid sperm immobilizing activity in medium with EC(50) values of 77 and 82 microM, respectively, and t(1/2) of < 3 min. Molecular modeling analysis indicated that sperm-immobilizing organic arsenicals exhibit high dipole moments (>7 Debyes). Sperm immobilizing activity of these arsenicals was completely abrogated in the presence of seminal plasma. Furthermore, coincubation of motile sperm with PHI-370 in the presence of reduced glutathione (GSH) resulted in dose-dependent protection of sperm motility and sperm motion parameters. Coincubation of the arsenical with GSH at a molar ratio of 1:20 resulted in 95% retention of sperm progressive motility. The mean values of the other sperm movement characteristics also showed > 90% protection. These observations suggest that the rapid sperm immobilizing activity of these pentavalent arsenicals may be as a result of direct binding of the arsenical with the sperm thiol components essential for sperm motility as well as induction of oxidative damage by disruption of sperm cell's antioxidant system. Sodium arsanilate and its N-substituted pyrimidine derivative, PHI-370, are useful probes to further evaluate the mechanism of pentavalent arsanilate-induced human sperm dysfunction.


Assuntos
Arsenicais/farmacologia , Glutationa/farmacologia , Imobilizantes dos Espermatozoides/farmacologia , Ácido Arsanílico/análogos & derivados , Ácido Arsanílico/farmacologia , Arsenicais/síntese química , Relação Dose-Resposta a Droga , Humanos , Cinética , Masculino , Substâncias Protetoras/farmacologia , Purinas/farmacologia , Pirimidinas/farmacologia , Quinazolinas/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Relação Estrutura-Atividade , Fatores de Tempo
13.
Contraception ; 19(3): 315-26, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-455982

RESUMO

An assay which allows relatively precise determination of the minimum concentration of test compound required to completely immobilize sperm is described. The use of rectangular cross-section capillaries to contain diluted semen allows facile direct comparison of many individual systems under well-controlled conditions. As a result, simultaneous determination of activity in both saline and serum media is feasible. Using this assay, abrupt loss of motility is observed between adjacent cepillaries differing in test compound concentration by as small a factor as 2 1/3 (1.260).


Assuntos
Imobilizantes dos Espermatozoides/farmacologia , Animais , Sítios de Ligação , Relação Dose-Resposta a Droga , Masculino , Compostos Organofosforados/farmacologia , Fosfinas/farmacologia , Coelhos , Sêmen/fisiologia
14.
Contraception ; 19(3): 207-12, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-455977

RESUMO

Early report by Kopp et al. have demonstrated that p-nitrophenyl-glycerol (PNPG) is an effective antiswarming agent in Proteus and that this inhibition may have been caused by PNPG interfering with the negative chemotaxis mechanism in the organism. With an inverted capillary assay, designed to test the motility response of rat epididymal spermatozoa to various suspending conditions including those exposed to chemical gradient, PNPG was shown in this study to exhibit an inhibitory effect at slightly higher than 10(-5) M. Moreover, this inhibitory effect appears to have stemmed from spermatozoa being repelled by PNPG as indicated by the observation that significantly less spermatozoa swim into a gradient of PNPG. The possibility of using spermatozoa repellents as contraceptives is discussed.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Glicerol/análogos & derivados , Nitrobenzenos/farmacologia , Animais , Glicerol/farmacologia , Masculino , Ratos , Imobilizantes dos Espermatozoides/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos
15.
Contraception ; 9(4): 333-45, 1974 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-4613535

RESUMO

PIP: Since the introduction of oral contraceptives and IUDs there has been a decline in the use of other methods. In 1961 contraceptive aerosol foam was introduced and has become widely used. Vaginal contraceptives are reasonably effective; no systemic side-effects are produced; there are no medical contraindications and they can be used without medical supervision. Results of in vitro tests do not necessarily correlate with clinical effectiveness. To be effective a spermicide must be able to immobilize sperm immediately. It has been shown that aerosol foam and vaginal cream are quickly dispersed over the walls of the vagina and external cervical os. Jelly was not as well distributed. Material from vaginal suppositories was also poorly distributed. Pregnancy rates for the various preparations have ranged from 1.3 to 30 per 100 women years. The higher rates were usually associated with less reliable groups of patients. A great number of substances have been tested; of these phenylmercuric acetate and the surface acting agents (long-chain compounds, detergents, and soaps) are most widely used today. Urea in sodium carboxymethyl cellulose has been found to be effective and has been used in India. A number of chelating agents have spermicidal properties. For some compounds chelation with various metals reduces the spermicidal effect while for others the resulting chelates are more toxic than either substance alone. Heavy metals have not been used clinically in recent years. Metallic copper and metallic iron immobilize spermatozoa in vitro but a relatively large amount of the metals or their salts are needed. Patient acceptability is an important factor. Vaginal foam has been widely acceptable. All the preparations of vaginal spermicides have to be used near the time of coitus. Silastic rings have been intended only for the absorption of the steroid into the general circulation. To warrant commercial development, any new spermicides would have to have advantage over agents already in clinical use. A particular area of interest is vaginal preparations for both contraception and prophylaxis against veneral infections. No single product has yet been approved for both purposes although those currently used have varying degrees of activity in vitro against sexually transmitted pathogens. Irreversible inhibition of acrosomal protease (acrosin) has been investigated in the rabbit and 1 compound, tosyllysine chloromethyl ketone (TLCK), has an antifertility effect when applied vaginally in rabbits. Local immunization against sperm-coating protein or a sperm fraction has been tried in animals. The efficacy of non-spermicidal agents in humans would need to be determined entirely by results of clinical trials.^ieng


Assuntos
Imobilizantes dos Espermatozoides/farmacologia , Espermicidas/farmacologia , Espermatozoides/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Quelantes/farmacologia , Anticoncepcionais Femininos/uso terapêutico , Eletrólitos , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Masculino , Gravidez , Infecções Sexualmente Transmissíveis/tratamento farmacológico , Reagentes de Sulfidrila/farmacologia , Tensoativos/farmacologia , Fatores de Tempo , Ureia/farmacologia , Vagina
16.
Contraception ; 53(6): 353-6, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8773422

RESUMO

The present study was undertaken to evaluate the effectiveness of Advantage 24 to inhibit sperm transport and survival when applied at 24 hours, 12 hours, and 15-30 minutes prior to a single act of intercourse. Conceptrol, applied at 15-30 minutes before intercourse, was employed as the comparative spermicide. One-hundred-thirty-nine women, aged 22 to 45 years, were enrolled into the study and 111 completed the trial. The ability of the spermicides to immobilize sperm was assessed by postcoital testing (PCT) and by examining the proportion of sperm immobilization failure (SIF) rates. SIF was a postcoital test result with > or = 10 sperm with progressive motility (either sluggish or rapid) per x 400 power field. Conceptrol and Advantage 24 used at 15-30 minutes were similar with respect to their ability to inactivate sperm (0% and 2% SIF, respectively, p = 0.5). At longer intervals between spermicidal application and intercourse, less inhibition of sperm motility was noted (9% and 14% SIF for 12 and 24 hours, respectively). The present study indicates that Advantage 24 is an effective agent to immobilize sperm. The action of Advantage 24 may decrease if it is applied earlier than 15-30 minutes before intercourse.


Assuntos
Nonoxinol/farmacologia , Imobilizantes dos Espermatozoides/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermicidas/farmacologia , Espermatozoides/efeitos dos fármacos , Administração Intravaginal , Adulto , Coito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Satisfação do Paciente , Seleção de Pacientes , Contagem de Espermatozoides , Espermatozoides/fisiologia , Fatores de Tempo , Resultado do Tratamento , Vagina/metabolismo , Cremes, Espumas e Géis Vaginais
17.
Contraception ; 31(5): 523-32, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-4028727

RESUMO

The effect of zoapatle aqueous crude extract (ZACE) was further studied and partially characterized upon human and rabbit spermatozoa. ZACE prepared from Montanoa tomentosa s.s.p tomentosa did not influence sperm motility or viability in a wide range of ZACE concentrations tested; on the other hand, ZACE prepared from Montanoa frutescens had immediate and constant inhibitory effect upon motility and decreased cell viability. Red cell lysis was readily observed with ZACE-frutescens, but not with ZACE-tomentosa. The effect of time on ZACE-frutescens potency for inducing red cell lysis was observed.


Assuntos
Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Oxepinas/farmacologia , Extratos Vegetais/farmacologia , Espermatozoides/efeitos dos fármacos , Animais , Bioensaio/métodos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Montanoa , Oxepinas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/análise , Coelhos , Imobilizantes dos Espermatozoides/isolamento & purificação , Imobilizantes dos Espermatozoides/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos
18.
Contraception ; 31(5): 487-97, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-2992880

RESUMO

A review of new Zoapatle publications was made, including five chemical compounds characterized recently. Relative potency of Kaurenoic acid, Kauradienoic acid (its mixture), Zoapatanol and Montanol was estimated in an in vitro guinea pig uterine assay. Kaurene compounds were several times more potent than Montanol and Zoapatanol as uteroactive substances. Zoapatle aqueous crude extract made from Montanoa frutescens had a strong in vitro uterine potency and unique in vivo characteristics in several biological systems, described in detail in the following five publications.


Assuntos
Oxepinas/farmacologia , Plantas Medicinais , Contração Uterina/efeitos dos fármacos , Abortivos não Esteroides/farmacologia , Aborto Induzido , Animais , Sistema Cardiovascular/efeitos dos fármacos , Colo do Útero/efeitos dos fármacos , Química Farmacêutica , Anticoncepcionais Femininos/farmacologia , Corpo Lúteo/efeitos dos fármacos , Cricetinae , Cães , Endométrio/efeitos dos fármacos , Feminino , Cobaias , Haplorrinos , Hemólise/efeitos dos fármacos , Humanos , Trabalho de Parto Induzido , Masculino , Camundongos , Montanoa , Extratos Vegetais/farmacologia , Plantas Medicinais/análise , Plantas Medicinais/ultraestrutura , Gravidez , Ratos , Receptores de Superfície Celular/efeitos dos fármacos , Imobilizantes dos Espermatozoides/farmacologia , Espermatozoides/efeitos dos fármacos , Relação Estrutura-Atividade , Vasoconstritores/farmacologia
19.
Asian J Androl ; 2(2): 103-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11232785

RESUMO

AIM: To examine if the seed extracts of Carica papaya, which showed antispermatogenic/sperm immobilization properties in animal models, could cause human sperm immobilization in vitro. METHODS: Chloroform extract, benzene chromatographic fraction of the chloroform extract, its methanol and ethyl acetate sub-fractions and the isolated compounds from the sub-fractions i.e., ECP 1 & 2 and MCP 1 &2, of the seeds of Carica papaya were used at concentrations of 0.1%, 0.5%, 1% and 2%. Sperm motility was assessed immediately after addition of extracts and every 5 minutes thereafter for 30 minutes. RESULTS: There were dose-dependent spermicidal effects showing an instant fall in the sperm motility to less than 20% at 2% concentration. Isolated compounds ECP 1 & 2 were more effective inducing a motility of less than 10%. Many of the spermatozoa became vibratory on the spot. Total inhibition of motility was observed within 20-25 min at all concentrations of all products. Scanning and transmission electron microscopy revealed deleterious changes in the plasma membrane of the head and mid-piece of spermatozoa. Sperm viability test and the number of abnormal spermatozoa after completion of incubation suggested that the spermatozoa were infertile. The effects were spermicidal but not spermiostatic as revealed by the sperm revival test. CONCLUSION: The results reveal spermicidal activity in vitro of the seed extracts of Carica papaya.


Assuntos
Frutas , Imobilizantes dos Espermatozoides/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Humanos , Masculino , Microscopia Eletrônica , Extratos Vegetais/farmacologia , Sementes
20.
Contraception ; 81(4): 355-61, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20227555

RESUMO

BACKGROUND: This study was conducted to determine the most effective fraction of the hydroethanolic (water:ethanol, 1:1) extracts of Stephania hernandifolia leaves and Achyranthes aspera roots (in a composite manner at a ratio of 1:3, respectively) that will provide maximum spermicidal activity in human and rat spermatozoa out of five different ratios (1:1, 1:3, 1:7, 3:1 and 7:1) that have been studied in pilot experiments. STUDY DESIGN: n-Hexane, chloroform and ethyl acetate fractions of the hydroethanolic (1:1) extracts of S. hernandifolia and A. aspera were mixed at 1:3. Different concentrations were tested for sperm immobilization, sperm viability, acrosome status, 5'-nucleotidase activity and nuclear chromatin decondensation using human and rat spermatozoa for the selection of the most effective concentration. RESULTS: Out of three fractions of the hydroethanolic (1:1) extracts of the said plants, the n-hexane fraction was most effective, and the chloroform fraction exhibited minimum activity for this purpose. At a concentration of 0.1 g/mL hexane fraction, all sperm of the human sample were immobilized immediately (within 20 s). In case of the rat sample, all epididymal spermatozoa were immobilized immediately (within 20 s) by treatment with hexane fraction at a concentration of 0.004 g/mL. All human sperm were found to be nonviable within 20 min. The activity of acrosome enzymes was reduced, and significant release of 5'-nucleotidase (a plasma membrane marker) into the surrounding medium was noted after treatment with 0.1 g/mL hexane fraction, indicating that the hexane fraction affected the cytoarchitecture of the sperm plasma membrane. The maximum number of human sperm failed to decondense when treated with 0.1 g/mL hexane fraction, and sperm motility was also irreversible. The hexane fraction was tested in rats as vaginal contraceptive and showed 100% efficacy, indicating its potential for development as vaginal contraceptive. CONCLUSION: The findings indicate that, among the different fractions, the hexane fraction of the hydroethanolic extracts of the two plants produced the most effective spermicidal activity and can be considered as vaginal contraceptive.


Assuntos
Achyranthes/química , Imobilizantes dos Espermatozoides/farmacologia , Espermicidas/farmacologia , Espermatozoides/efeitos dos fármacos , Stephania/química , Acrossomo/efeitos dos fármacos , Animais , Feminino , Humanos , Masculino , Extratos Vegetais/química , Ratos , Solventes/química
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