Generation of oligomers of subunit vaccine candidate glycoprotein D of Herpes Simplex Virus-2 expressed in fusion with IgM Fc domain(s) in Escherichia coli: A strategy to enhance the immunogenicity of the antigen

Glycoprotein D (gD) of Herpes Simplex Virus-2 is used as an antigen in various anti-herpes subunit vaccines owing to its involvement in binding the host cell receptors for host infectivity. However, most of these monomeric protein based candidates have shown low immunogenicity in animal models. To enhance the immunogenicity of gD, a fresh approach of fusing its ectodomain with the Fc domain(s) of IgM has been adopted to oligomerize the viral antigen and to exploite the immune-modulating potential of IgM Fc. Six vaccine constructs, generated by fusing three gD-ectodomain-length-variants with the Ig µ-chain domain 4 (µCH4) and µCH3-CH4 fragment, were cloned in Escherichia coli using pET28b( +) vector. The vaccine proteins were expressed in the form of inclusion bodies (IBs) and were in vitro refolded into protein oligomers of high stoichiometries of ~ 15–24, with 70–80% refolding yields. The conformations of gD and Fc components of the refolded oligomers were analyzed by ELISA and CD spectroscopy and were found to be native-like. The sizes and profiles of the size-distribution of oligomers were determined by dynamic light scattering (DLS). The candidate C2 (gD-μCH3-CH4), showing the most compact oligomer size and uniform distribution of its particles was chosen as the suitable candidate for mice immunization studies to assess the immunogenicity of the antigen gD. The C2 oligomer stimulated a strong anti-gD humoral response with an antibody titer of 102,400 and a strong, biased Th1 immune response in C57BL/6 mice, indicating its potential as a strong immunogen which may serve as an effective vaccine candidate.

An in vitro refolding method to produce oligomers of anti-CHIKV, E2-IgM Fc fusion subunit vaccine candidates expressed in E. coli

Recombinant envelope protein-1 (E1) and E2 of Chikungunya virus (CHIKV) has been shown to elicit neutralizing antibodies and a balanced Th1/Th2 response in mice however with limited protection. Recently reported CHIK virus-like particles showed augmented immunity and protection in adult mice in comparison to E1 and E2, however exacerbated the disease in aged subjects. In order to improve the overall efficacy of protein based vaccines, novel strategies need to be adopted. The discovery of IgM Fc receptor (FcμR) and its role in humoral immune response led us to hypothesise that fusion of an antigen with Fc of IgM may enhance its immunogenicity by polymerizing it and FcμR mediated activation of B and other immune cells. We report in the current study, expression of E2 subunit of CHIKV in fusion with various IgM Fc domains/peptides in E. coli, their in-vitro refolding, characterization and immune response in C57BL/6 mice. Candidates fused with CH3-CH4 Fc fragment produced stable oligomers, whereas the one fused with peptides remained monomeric. The latter elicited a strong humoral and a balanced Th1/Th2 response in mice, whereas the polymeric candidate despite eliciting a strong humoral response, stimulated a biased Th1 response and exhibited higher virus neutralization in Vero cells.

RISUG® as a male contraceptive: journey from bench to bedside

Even after decades of research men still lack reliable and reversible contraceptive methods comparable to female methods of contraception. Traditional methods of male contraception present a high failure rate and also involve high risk both when used for contraception and for protection against sexually transmitted diseases. Various chemical, hormonal, immunological, vas based and herbal methods of contraception have been examined by scientists world over during the past four decades. Among the possible lead approaches, exogenous hormonal contraception, either alone or in combination with progesterone or antiandrogen, is being viewed at low profile because of their insufficiency in inducing uniform suppression of spermatogenesis and steroid related long term complications. As an alternative to vasectomy, among various intravasal devices being examined, RISUG® (Reversible Inhibition of Sperm Under Guidance), a co-polymer of styrene and maleic anhydride offers long term contraception with safety, efficacy and it can be delivered by no-scalpel injection. Thus it is the only male contraceptive procedure currently under Phase- III Clinical Trial. The non-invasive reversal technique, successfully demonstrated in langur monkeys and functional reversal achieved with dimethyl sulphoxide (DMSO) and sodium bicarbonate (NaHCO3) in rats and rabbits with safety at F1 generation (first filial generation) have projected RISUG® as a better alternative to vasectomy. In this narrative review we revisit the long journey of RISUG® beginning with formulation on a bench towards reaching the market as a safe and effective contraceptive method, discussing various milestones and roadblocks of this expedition awaiting the mandatory regulatory clearance from the Government of India. Successful completion of ongoing phase III clinical trials with demonstration of reversal in human volunteers will give an indigenously developed male contraceptive to the world.

Pre-clinical Validation of Mito-targeted Nano-engineered Flavonoids Isolated From Selaginella bryopteris (Sanjeevani) As A Novel Cancer Prevention Strategy

BACKGROUND

Novel bioactive plant secondary metabolites, including flavonoids, offer a spectrum of chemo-protective responses against a range of human tumor models. However, the clinical translation of these promising anti-cancer agents has been hindered largely by their poor solubility, rapid metabolism, or a combination of both, ultimately resulting in poor bioavailability upon oral administration.

OBJECTIVE

To circumvent the challenges associated with herbal drug development and for effective integration into clinical setting, nano-engineering is one of the emerging pragmatic strategies which has promise to deliver therapeutic concentrations of bio-actives upon oral administration.

METHOD

We assessed the nano-encapsulated flavonoid-rich fraction isolated from a traditional Indian herb Selaginella bryopteris (Sanjeevani) (NP.SB). Both in vitro and in vivo studies were performed to evidence the epigenetic protection mechanisms of NP.SB through a mitochondrial-targeted pre-clinical validation strategy.

RESULTS

The mito-protective activity of NP.SB revealed a dose-dependent effect when tested in GC-1 spg (mouse spermatogonial epithelial) and B/CMBA.Ov (mouse ovarian epithelial) following exposure to Nsuccinimidyl N-methylcarbamate, a potential human carcinogen. Smaller size, rapid internalization, faster mobility and site specific delivery conferred significant cancer protection in cultured cells. Notably, this encapsulated flavonoid supplementation; prevented emergence of neoplastic daughter clones from senescent mother phenotypes in pro-oxidant treated GC-1 spg and B/CMBA.Ov cells by selective abrogation of mitochondrial oxidative stress-induced aberrant epigenetic modifications. In vivo studies using a diethylnitrosamine and 2- acetylaminofluorene mouse model demonstrated that NP.SB has a significant inhibitory effect on tumor growth which clearly substantiated our in vitro findings.

CONCLUSION

Anti-carcinogenic property in conjunction with low toxicity of NP.SB, underscores the translational significance of dietary flavonoids as cancer-protective agents for preferential application in clinical settings.

Toxicity and Mutagenicity Evaluation Following RISUG Contraception Reversal in Rats

Reestablishment of fertility, after a male contraceptive method, is of great concern. In this context, RISUG (Reversible Inhibition of Sperm Under Guidance) has been evaluated for its mutagenicity following reversibility with dimethyl sulfoxide (DMSO)/sodium bicarbonate (NaHCO3) in Wistar albino rats. Animals were divided into 7 groups, namely, sham-operated control, vas occlusion with RISUG for 90 and 360 days, reversal with DMSO and NaHCO3 after 90 and 360 days, respectively. The testis, cauda epididymis, cauda epididymal spermatozoa, and serum were evaluated for apoptosis and hormonal status through various assays. RISUG was subjected to Ames test at dose levels of 10, 50, and 100 µL. Results of terminal deoxynucleotidyl transferase nick end labeling and caspase-3 assays in testes and cauda epididymis revealed that the percentage of positive cells in the experimental groups was comparable to sham-operated control. Annexin V assay in cauda epididymal spermatozoa showed slight elevation in group II ( P < 0.05), whereas in the remaining groups, minimum numbers of positive sperms were found. Hormone profile, namely, testosterone, prolactin, cortisol, prostate-specific antigen, and sperm antibody concentration, remained unchanged. In Ames test, no significant increase was observed in the number of revertant colonies on plates containing RISUG in the presence and absence of S9 mix in all 3 strains. Therefore, the reversal of RISUG-induced contraception by solvent vehicle DMSO/NaHCO3 was successful without any toxicity at the cellular levels.

Contraception with RISUG® and functional reversal through DMSO and NaHCO3 in male rabbits

The study aimed to evaluate reversal of short- and long-term vas occlusion with reversible inhibition of sperm under guidance (RISUG) using dimethyl sulfoxide (DMSO) and sodium bicarbonate (NaHCO3) in male rabbits (Oryctolagus cuniculus). Animals were divided into seven groups containing five animals each. Fortnightly, semen analysis revealed that sperm concentration and output steadily declined after vas occlusion and complete azoospermia was attained at 30-60 days postinjection. Spermatozoa reappeared at 60-75 days of reversal and normozoospermia was noticed between 135 days and 150 days in the reversal groups. All spermatozoa were found nonmotile prior to azoospermia and a gradual recovery in sperm motility was observed between 105 days and 135 days of reversal. A significant decline in viability of sperms was noticed during vas occlusion up to 30-60 days which recovered at 60-75 days postreversal and normalized by 75-105 days in the reversal groups. A significant enhancement in the sperm abnormalities was recorded in all vas occluded animals as well as those in initial periods of reversal. Other parameters, namely, semen volume, ejaculation time, pH, color, and consistency, remained unaltered during all phases of the study. Fertility test, at the intervals of 15 days, demonstrated that animals exhibited complete sterility during the entire period of vas occlusion. A gradual recovery in fertility was observed with the appearance of spermatozoa following vas occlusion reversal and 100% fertility was observed following 135-150 days of reversal. F1 progeny of reversed animals was found normal. The results suggest that reversal with DMSO or NaHCO3 is feasible, with normal progeny, following short- and long-term contraception.

Indian folklore medicine in managing men's health and wellness

India is a home for a large variety of plants with remarkable medicinal and pharmacological value. Traditional medicine in the form of Ayurveda, Siddha and Unani has used many of these plants since ancient days for treating and curing various ailments of the body. When it comes to issues related to reproductive health, people still hesitate to discuss and/or accept it openly and hence look for alternate and natural remedies. The various tribal populations distributed across different parts of the country still use these plant extracts in various formulations for maintenance of good health. The medical utilities of several of these plants have been documented; however, there are many more, whose potential is yet to be explored. This review discusses the role of various plants grown in the Indian subcontinent that have been widely used in maintaining various aspects of reproductive health in men such as infertility, aphrodisiac, contraception, libido, sexually transmitted infections and reproductive tract cancers as well as in treating chronic disorders.

Comparative assessment of lipid based nano-carrier systems for dendritic cell based targeting of tumor re-initiating cells in gynecological cancers

We aimed to identify an optimum nano-carrier system to deliver tumor antigen to dendritic cells (DCs) for efficient targeting of tumor reinitiating cells (TRICs) in gynecological malignancies. Different lipid based nano-carrier systems i.e. liposomes, ethosomes and solid lipid nanoparticles (SLNPs) were examined for their ability to activate DCs in allogeneic settings. Out of these three, the most optimized formulation was subjected for cationic and mannosylated surface modification and pulsed with DCs for specific targeting of tumor cells. In both allogeneic and autologous trials, SLNPs showed a strong ability to activate DCs and orchestrate specific immune responses for targeting TRICs in gynecological malignancies. Our findings suggest that the mannosylated form of SLNPs is a suitable molecular vector for DC based therapeutics. DCs pulsed with mannosylated SLNPs may be utilized as adjuvant therapy for specific removal of TRICs to benefit patients from tumor recurrence.

Relative suitability of DMSO and NaHCO3 for reversal of RISUG® induced long-term contraception

Among the vas-based methods on trial, reversible inhibition of sperm under guidance (RISUG(®) ), a co-polymer of styrene and maleic anhydride is being projected as an effective alternative to No Scalpel Vasectomy. RISUG offers long-term contraception with safety, efficacy in human trials and can be delivered by no-scalpel injection. Currently, the procedure is under phase-III clinical trial. However, reversal of this vas-based drug-induced contraception needs to be established in animal models prior to clinical trials to ensure its claim as an effective alternative for vasectomy. In the present investigation, the relative suitability of dimethyl sulphoxide (DMSO) and NaHCO3 for RISUG induced long-term vas occlusion reversal was carried out in albino rats. Animals were allocated into four groups (n = 10), viz., sham-operated control (group-I), vas occlusion with RISUG for 360 days (group-II), vas occlusion with RISUG for 360 days and reversal with DMSO (group-III) and vas occlusion with RISUG for 360 days and reversal with NaHCO3 (group-IV). A variable response in fertility was observed in different groups. Absolute sterility in group III at all mating intervals, while, zero percent fertility in groups II and IV following 90 days of occlusion was observed. Following reversal restoration of fertility with DMSO at 45 days, whereas, reversal by NaHCO3 at 30 days was noticed. Ejaculated spermatozoa of RISUG injected and initial intervals of reversed animals exhibited various degrees of abnormalities. The testes exhibited focal degeneration in vas occluded animals. The occluded lumen of the vas deferens contained an eosinated polymer with exfoliated epithelium. Following vas occlusion reversal, a complete regeneration in the vas epithelium was seen. All other parameters remained unaltered. The reversal with NaHCO3 resulted into an early resumption of fertility when compared with DMSO and the procedure found to be successful, feasible and safe up to F1 generation. Thus, RISUG provides a hope for reversible male contraceptives.

Down regulation of SPAG9 reduces growth and invasive potential of triple-negative breast cancer cells: possible implications in targeted therapy

BACKGROUND

Recently, we reported an association of a novel cancer testis (CT) antigen, sperm-associated antigen 9 (SPAG9) expression in breast cancer clinical samples, indicating its potential role in carcinogenesis. Around 15% breast cancers are designated as triple-negative for which treatment modalities are limited. Therefore, in the present study, we assessed the role of SPAG9 in triple-negative breast cancer cells.

METHODS

SPAG9 mRNA and protein expression was investigated in various breast cancer cells of different hormone receptor status and different subtypes by employing reverse transcriptase-polymerase chain reaction (RT-PCR), real time PCR, Western blotting, indirect immunofluorescence (IIF) and fluorescence activated cell sorting (FACS). Employing plasmid-based small interfering RNA (siRNA) approach, knockdown of SPAG9 was carried out in triple-negative breast cancer cells, MDA-MB-231, to assess its role on various malignant properties in vitro and in vivo.

RESULTS

SPAG9 mRNA and protein expression was detected in all breast cancer cells. Further, IIF results showed that SPAG9 was predominantly localized in the cytoplasm of breast cancer cells. FACS analysis revealed distinct SPAG9 surface localization in breast cancer cells. Gene silencing of SPAG9 resulted in significant reduction in cellular proliferation, colony forming ability, migration, invasion and cellular motility of MDA-MB-231 cells. Further, ablation of SPAG9 expression resulted in reduction in the tumor growth of human breast cancer xenograft in nude mice in vivo.

CONCLUSIONS

In summary, our data indicated that down regulation of SPAG9 reduces growth and invasive potential of triple-negative breast cancer cells, suggesting that SPAG9 may be a potential target for therapeutic use.

Fertility, developmental toxicity and teratogenicity in albino rats treated with methanol sub-fraction of Carica papaya seeds

Objective:

To evaluate the status of fertility, developmental stages during gestation and teratological changes, if any, following oral administration of methanol sub-fraction (MSF) of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in rats.

Materials and Methods:

The MSF was administered at the doses of 50 mg contraceptive dose (CD), 100 mg (2× CD), 250 mg (5× CD) and 500 mg (10× CD)/kg body wt/day along with vehicle-treated control using 10 male and 20 female Wistar rats in each group. Necropsies were performed one day before the expected parturition. Status of gravid/non-gravid uterus, the number of corpora lutea in the ovary, implantation status, fetal wellbeing, fetal resorption, fetal body weight, external, visceral and skeletal malformations were recorded.

Results:

Pregnancies were recorded in vehicle-treated control animals and in the animals treated with 50 mg/kg body wt/day. The animals treated with 2× CD, 5× CD and 10× CD did not get pregnant. The fetuses and the status of the ovary, uterus and implantation, fetal body weight, soft tissues and skeletal structures were recorded normal. Data were comparable to those of control.

Conclusion:

The results suggest that the test substance had no developmental toxicity and teratogenicity which could affect pregnancy, implantation and gestation.

Mycobacterium indicus pranii is a potent immunomodulator for a recombinant vaccine against human chorionic gonadotropin

The objective of this work was to identify a human use-permissible adjuvant to enhance significantly the antibody response to a recombinant anti-hCG vaccine. Previous Phase II efficacy trials in sexually active women have demonstrated the prevention of pregnancy at hCG bioneutralization titers of 50ng/ml or more. Mycobacterium indicus pranii (MIP), a non-pathogenic Mycobacterium employed as an autoclaved suspension in aqueous buffer, significantly increased antibody titers in the FVB strain of mice. Three other genetic strains of mice: SJL, C3H, and C57Bl/6 responded with antibody titers several-fold higher than 50 ng/ml, which is the protective threshold in women, although there were differences in the peak titers attained. In addition, the duration of the antibody response was lengthened. The vaccine hCGβ-LTB, given together with MIP, induces both a Th1 and Th2 response, which is reflected in the production of not only IgG1, but also a high proportion of IgG2a and IgG2b antibodies.

Safety evaluation of long term oral treatment of methanol sub-fraction of the seeds of Carica papaya as a male contraceptive in albino rats

ETHNOPHARMACOLOGICAL RELEVANCE

The manuscript is one of the series of attempts in authenticating scientific documentation of the seeds of Carica papaya being traditionally used for contraception.

AIMS OF THE STUDY

To establish safety of the methanol sub-fraction (MSF) of the seeds of Carica papaya as a male contraceptive following long term oral treatment.

MATERIALS AND METHODS

MSF was administered orally to albino rats at multiples of contraceptive dose (CD) at 50 (1x), 100 (2x), 250 (5x) and 500 (10x)mg/kg body weight daily for 52 weeks. Body weight, organs weight, morbidity, mortality, clinical chemistry, sperm analysis, histopathology and serum testosterone were evaluated to assess the safety and contraceptive efficacy.

RESULTS

MSF treatment at various dose regimens, daily for 52 weeks did not show significant changes in body weight, organs weight, food and water intake and pre-terminal deaths compared to those of control animals. Sperm count and viability in 50mg/kg body weight treated animals and the weight of epididymis, seminal vesicle and prostate of all the treated animals showed significant reduction compared to control. Cauda epididymal spermatozoa of 50mg/kg body weight treated animals were immotile. Azoospermia was observed in 100, 250 and 500 mg/kg body weight treated animals. Serum clinical parameters, serum testosterone and histopathology of vital organs were comparable to those of control animals. Histology of testis revealed adverse effects on the process of spermatogenesis, while the histology of epididymis, seminal vesicles and ventral prostate showed no changes compared to control.

CONCLUSION

The long term daily oral administration of MSF affects sperm parameters without adverse side effects and is clinically safe as a male contraceptive.

A partner monoclonal antibody to Moab 730 kills 100% of DU145 and PC3 androgen-independent cancer cells

A number of therapeutic options are available for patients with prostate carcinoma till the time that the tumour is hormone dependent. However, no fully effective therapy is available for the treatment of androgen-independent prostate carcinomas. Antibodies directed at epitopes unique to or overexpressed on the cancer cells could be of therapeutic utility. A monoclonal antibody (Moab) 2C4 has been generated, which binds with cells of two androgenindependent prostate cancers, DU145 and PC3, and does not bind to peripheral blood leukocytes (PBLs) of healthy donors. This antibody, along with the previously developed Moab 730, kills 100% of both DU145 and PC3 cells in the presence of complement and does not have a deleterious effect on PBLs of healthy males. The anti-tumour action of the two antibodies prevents the establishment of DU145 cell tumour in nude mice in vivo. Moab 2C4 in combination with 730 has potential for use as therapy for androgen-independent cancers.

Sperm characteristics and teratology in rats following vas deferens occlusion with RISUG and its reversal

The functional success of the reversal of vas occlusion by styrene maleic anhydride (RISUG), using the solvent vehicle, Dimethyl Sulphoxide (DMSO), has been investigated. Reversal with DMSO was carried out in Wistar albino rats 90 days after bilateral vas occlusion. The body weight, organ weight, sperm characteristics, fertility test and teratology, including skeletal morphology were evaluated in vas occlusion and reversal animals and in F(1) progenies to assess the functional success of the occlusion and reversal. Body weight, organ weight and the cauda epididymal sperm characteristics of vas occlusion and reversal animals and of F(1) progenies were comparable to control. Ejaculated spermatozoa in the vaginal smear showed detached head/tail, acrosomal damage, bent midpiece, bent tail and morphological aberrations in sperm head after vas occlusion, which returned to normal, 90 days after reversal. Monthly fertility test, post-injection showed 0% fertility, which improved gradually and 100% fertility was achieved 90 days after reversal. The fertility/pregnancy/implantation record and skeletal morphology of the offspring were comparable to control. The results suggest functional success and safety of vas occlusion reversal by DMSO.

Metabolic properties of lactobacilli in women experiencing recurring episodes of bacterial vaginosis with vaginal pH >or= 5

While 60% of women experiencing recurring episodes of bacterial vaginosis (BV) with vaginal pH >or= 5 are depleted of resident probiotic lactobacilli, the remainder carry one or more strains of lactobacilli. Their ability to make D-lactic acid is, however, low (3.94 +/- 0.72 mM/L) compared to the D-lactic acid produced by strains from healthy vagina with vaginal pH approximately 4 (8.04 +/- 1.07 mM/L) culture supernatant of 0.5 McFarland concentration (P < 0.001).

Sperm characteristics and ultrastructure of testes of rats after long-term treatment with the methanol subfraction of Carica papaya seeds

The contraceptive efficacy of Carica papaya seeds after short-term evaluation has been well established. We have examined the safety and mechanism of contraception in rats after long-term treatment with the methanol subfraction (MSF) of C. papaya seeds. The test substance was administered orally to the male albino rats (n = 40) at 50 mg per kg body weight each day for 360 days. Control animals (n = 40) received olive oil as a vehicle. Recovery was assessed up to 120 days after treatment withdrawal. Sperm parameters, serum testosterone levels, fertility, histology and ultrastructure of the testis, haematology and serum clinical chemistry were evaluated to establish the safety and efficacy of the test substance. Safety of long-term treatment was evidenced by unaltered health status, organ weight, haematology and clinical chemistry, and by an increase in body weight. The mechanism of contraception was shown by reduction in nuclear and cytoplasmic volume, normal nuclear characteristics and vacuolization in the cytoplasmic organelles of the Sertoli cells, as well as nuclear degeneration in spermatocytes and spermatids indicating disturbed spermatogenesis. Leydig cells were normal. Initial effects were observed in Sertoli cells at 60 days of treatment. Spermatocytes and spermatids were affected after 120-240 days of treatment. A significant decline in sperm count and viability, total inhibition of sperm motility, increased numbers of sperm abnormalities, normal serum testosterone levels and 100% sterility were evident after 60 days of treatment. All the altered parameters, including percent fertility, were restored to control level 120 days after treatment withdrawal. It is concluded that the MSF is safe for long-term treatment and the mechanism of contraception is shown by its effect on spermatid differentiation in the testis, possibly mediated by the Sertoli cell factors.

Selective killing of leukemia and lymphoma cells ectopically expressing hCGbeta by a conjugate of curcumin with an antibody against hCGbeta subunit

OBJECTIVE

A variety of cancers ectopically express human chorionic gonadotropin beta (hCGbeta). Patients harboring such cancers have poor prognosis and adverse survival. A recombinant chimeric antibody, cPiPP, exhibiting high affinity and specificity for hCGbeta/hCG was engineered. This study was designed to determine whether this antibody alone or conjugated to curcumin can selectively kill tumor cells expressing hCGbeta.

EXPERIMENTAL DESIGN

The study was carried out on MOLT-4 and U-937 cells expressing hCGbeta and on peripheral blood leukocytes of acute myeloid leukemia (AML) patients. The anticancerous compound curcumin was conjugated to cPiPP. The binding of cPiPP and cPiPP-curcumin conjugate to cells was studied by flow cytometry and cytotoxicity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), FACS with propidium iodide staining, trypan blue exclusion assay and microscopy.

RESULTS

The antibody did not impair the growth of MOLT-4 and U-937 cells in culture. Its conjugate with curcumin, however, was lethal to both cell lines. The immunoconjugate killed tumor cells bearing the CD33 marker of an AML patient expressing hCGbeta but did not have a similar action on cells of another AML patient with the CD13 marker but who was negative for hCGbeta.

CONCLUSION

A humanized antibody against hCGbeta linked to curcumin has potential for therapy of hCGbeta-expressing tumors.

Sperm motility inhibitory effect of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in langur monkey, Presbytis entellus entellus

AIM

To assess the contraceptive efficacy of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in langur monkeys.

METHODS

The test substance was given p.o. to five monkeys at 50 mg/kg body weight/day for 360 days. Control animals (n=3) received olive oil as vehicle. Sperm parameters as per World Health Organization standards, sperm functional tests, morphology of testis and epididymis, haematology, clinical biochemistry, serum testosterone and libido were evaluated. Following completion of 360 days treatment the animals were withdrawn from the treatment and the recovery pattern was assessed by semen analysis and sperm functional tests.

RESULTS

Total inhibition of sperm motility was observed following 60 days of treatment that continued until 360 days study period. Sperm count, percent viability and percent normal spermatozoa showed a drastic decline following 30 days of treatment. Sperm morphology showed predominant mid piece abnormalities. Sperm functional tests scored in sterile range. Histology and ultrastructure of testis revealed vacuolization in the Sertoli cells and germ cells. Loss of cytoplasmic organelles was evident in spermatocytes and round spermatids. Histology and ultrastructure of epididymis of treated animals were comparable to those of control animals. Hematological and serum clinical parameters and testosterone levels fluctuated within the control range throughout the study period. Recovery was evident following 60-120 days of treatment withdrawal.

CONCLUSION

The results suggest that the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya shows contraceptive efficacy without adverse toxicity, mediated through inhibition of sperm motility.

Toxicological investigations on the methanol sub-fraction of the seeds of Carica papaya as a male contraceptive in albino rats

Pre-clinical acute and sub-chronic toxicity studies of the methanol sub-fraction (MSF) of the seeds of Carica papaya, a putative male contraceptive, have been investigated in rats to evaluate safety of the test substance. A single oral dose of MSF at 2000 mg/kg body weight was studied over 14 days for acute toxicity, and daily oral doses of 50, 100, 250 and 500 mg/kg body weight were studied for 28- and 90-day periods for sub-chronic toxicity. Body weight, food and water intake and phenotypical toxicological symptoms were recorded daily. Sperm analysis, hematology, serum clinical biochemistry, libido and pathological examination of vital organs were recorded at the termination of the experimental periods. We observed no overt general toxicity in exposed animals. Food and water intake showed daily fluctuations within control limits. Sperm density showed a significant decrease in all 28- and 90-day repeated dose treated animals whereas total sperm motility inhibition was observed at 250 and 500 mg/kg dose levels at the 28-day time interval but in all dose groups at the 90-day interval. The preliminary results suggest the test substance may be a safe approach to male anti-fertility.

Perspectives of contraceptive choices for men

Apart from condoms and vasectomy, which have several limitations of their own, no other methods of contraception are available to men. Various chemical, hormonal, vas based and herbal contraceptives have been examined and few of them have reached the stage of clinical testing. Promising leads have been obtained from testosterone buciclate/undecanoate, alone or in combination with levonorgestrel butanoate or cyproterone acetate, RISUG, an injectable intravasal contraceptive and a few herbal products, particularly the seed products of Carica papaya. It is feasible that an ideal male contraceptive, that meets out all the essential criteria will be made available to the community in the near future.

Safety evaluation of long-term vas occlusion with styrene maleic anhydride and its non-invasive reversal on accessory reproductive organs in langurs

AIM

To evaluate the safety of the long term vas occlusion with styrene maleic anhydride (SMA) and its non-invasive reversal at the level of accessory reproductive glands ARGs in langurs.

METHODS

The morphology of seminal vesicle and ventral prostate was evaluated by light as well as transmission electron microscopy. Serum clinical chemistry and urine albumin were evaluated in an autoanalyzer using reagent kits. Fructose, acid phosphatase and zinc in the seminal plasma were evaluated spectrophotometrically according to the WHO manual. Serum testosterone, prostate specific antigen and sperm antibodies were evaluated by enzyme-linked immunosorbent assays (ELISA) using reagent kits and hematology was estimated according to standard procedures.

RESULTS

The morphological features and secretory activity of the seminal vesicle and prostate were normal as evidenced by the presence of well-developed mitochondria, rough endoplasmic reticulum, Golgi bodies, secretory granules and normal nuclear characteristics throughout the course of investigation. Serum testosterone and prostate specific antigen remained unaltered and serum antisperm antibodies level presented negative titres. Urine albumin was nil. Total red blood corpuscles (RBC), white blood corpuscles (WBC), hemoglobin (Hb) and red cell indices, serum protein, glucose, cholesterol, creatinine, creatine kinase (CK), serum glutamate oxalate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), lactate dehydrogenase (LDH), bilirubin, urea, triglycerides and high-density lipoprotein (HDL) did not show appreciable changes following vas occlusion and after its non-invasive reversal. Although fructose, acid phosphatase (ACP) and zinc in the seminal plasma showed a significant reduction following vas occlusion, it could not be related to the morphology of seminal vesicle and prostate.

CONCLUSION

SMA vas occlusion and its non-invasive reversal do not damage the accessory reproductive organs.

Efficacy trial on the purified compounds of the seeds of Carica papaya for male contraception in albino rat

The contraceptive efficacy and toxicological screening of the two principal compounds, MCP I and ECP I, isolated from the seeds of Carica papaya, in male albino rats at the standardized dose regimen, at 50 mg/kg b.w./day, for a period of 360 days and up to 90 days of treatment withdrawal have been reported. The body and organ weights, cauda epididymal sperm characteristics, androgen sensitive tissue biochemistry, reactive oxygen species and anti-oxidant defense system in the cauda epididymal microenvironment, histology and ultrastructure of testis and cauda epididymis, histology of seminal vesicle and prostate, toxicological investigations through routine hematology and serum clinical chemistry, sexual behaviour and fertility index have been studied. The results revealed that oral administration of MCP I and ECP I were equally effective, exhibiting complete inhibition of sperm motility following 90 days of treatment that coincided with a gradual and significant decline in cauda epididymal sperm density, percent viable spermatozoa and significant increase in sperm anomalies. Histology of testis of treated animals revealed degenerated germinal epithelium, vacuolization in Sertoli cells and proliferating germ cells and disturbances in spermatid differentiation. Spermatogonial stem cell reserves and Leydig cells appeared normal. Ultrastructure of the testis revealed vacuolization in the Sertoli cells and germ cells, loss of cytoplasmic characteristics in the Sertoli cells, nuclear degeneration and mitochondrial vacuolization in spermatocytes and spermatids. Leydig cells exhibited steroidogenic features. Cauda epididymis showed normal epithelial cell function. Absence of spermatozoa or disruption of spermatozoa clusters in the lumen were evident. Ultrastructure of cauda epididymis revealed normal secretory activity. Morphology of seminal vesicle and prostate of the treated animals were comparable to control animals. Serum testosterone, tissue biochemical and toxicological parameters remained unaffected. Fertility test revealed 100% efficacy. All the altered parameters showed sign of recovery following 90 days of treatment withdrawal. It is concluded that both MCP I and ECP I are equally effective in terms of contraceptive efficacy which is likely reversible and without adverse side effects.

Preclinical evaluation for noninvasive reversal following long-term vas occlusion with styrene maleic anhydride in langur monkeys

A preclinical evaluation for reversal through a noninvasive approach following long-term vas occlusion with styrene maleic anhydride (SMA) has been attempted in langur monkeys at the level of semen parameters, sperm functional tests, semen biochemistry, histology and ultrastructure of reproductive organs, hematology and serum clinical biochemistry including antisperm antibodies (ASA), prostate-specific antigen (PSA) and testosterone. Noninvasive reversal through palpation, percutaneous squeezing and electrical stimulation, forced vibratory movements and suprapubic percussion in the inguinal segments and per-rectal digital massage was attempted in seven langur monkeys after 540 days following vas occlusion. The results revealed instant azoospermia reversal on the same day of reversal with impaired sperm quality, which showed gradual improvement and normospermia with normal motility and viability after 60-90 days of reversal. Sperm functional tests, including ultrastructure of spermatozoa, indicative of sterility in the initial ejaculations, reached normalcy after 90-120 days of reversal. The seminal plasma biochemistry indicative of obstructive azoospermia regained a normal pattern after 90-120 days of reversal. The morphology of testes that showed focal degeneration during 540 days of vas occlusion and that of vasa deferentia that showed exfoliation of epithelial cells resumed to normal morphology comparable with control animals after 150 days of reversal. The morphology of the epididymis, seminal vesicle and prostate did not show appreciable changes following vas occlusion and after noninvasive reversal compared with those of control animals. Hematology, serum clinical chemistry, ASA, PSA and testosterone fluctuated within control limits, indicating safety of the procedure at the level of accessory reproductive organs. The results suggest that noninvasive reversal is feasible even after long-term vas occlusion with SMA and is safe without adverse side effects.

Ultrastructural changes in the testis and epididymis of rats following treatment with the benzene chromatographic fraction of the chloroform extract of the seeds ofCarica papaya

The benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya at a dose of 10 mg/rat/day for 150 days, which has shown a total inhibition of motility, reduced sperm count and infertility, was tested to de fi ne the mode of action at the subcellular level in the testis and epididymis. The ultrastructure of the testis of the treated animals revealed no appreciable changes in the subcellular characteristics. The mechanism of protein synthesis as well as steroidogenesis were evident in the Sertoli cells while the spermatogonia, spermatocytes and spermatids, both round and elongated, depicted a prominent nucleus, distinct nuclear membrane and cytoplasmic characteristics indicating normal germ cell differentiation. The principal cells of the cauda epididymis were characterized by the presence of well-de fi ned rough endoplasmic reticulum, mitochondria, Golgi bodies and secretary granules, suggesting active secretory functions. The absorptive function of the cauda epididymis was evidenced by the presence of numerous vesicles and multivesicular bodies adjacent to stereocilia. It is concluded that the inhibition of sperm motility by the drug could be due to other epididymal factors rather than the subcellular characteristics of testis and epididymis.

Linkage of interactions in sickle hemoglobin fiber assembly: inhibitory effect emanating from mutations in the AB region of the alpha-chain is annulled by a mutation at its EF corner

The AB and GH regions of the alpha-chain are located in spatial proximity and contain a cluster of intermolecular contact residues of the sickle hemoglobin (HbS) fiber. We have examined the role of dynamics of AB/GH region on HbS polymerization through simultaneous replacement of non-contact Ala(19) and Ala(21) of the AB corner with more flexible Gly or rigid alpha-aminoisobutyric acid (Aib) residues. The polymerization behavior of HbS with Aib substitutions was similar to the native HbS. In contrast, Gly substitutions inhibited HbS polymerization. Molecular dynamics simulation studies of alpha-chains indicated that coordinated motion of AB and GH region residues present in native (Ala) as well as in Aib mutant was disrupted in the Gly mutant. The inhibitory effect due to Gly substitutions was further explored in triple mutants that included mutation of an inter-doublestrand contact (alphaAsn(78) --> His or Gln) at the EF corner. Although the inhibitory effect of Gly substitutions in the triple mutant was unaffected in the presence of alphaGln(78), His at this site almost abrogated its inhibitory potential. The polymerization studies of point mutants (alphaGln(78) --> His) indicated that the inhibitory effect due to Gly substitutions in the triple mutant was synergistically compensated for by the polymerization-enhancing activity of His(78). Similar synergistic coupling, between alphaHis(78) and an intra-double-strand contact point (alpha16) mutation located in the AB region, was also observed. Thus, two conclusions are made: (i) Gly mutations at the AB corner inhibit HbS polymerization by perturbing the dynamics of the AB/GH region, and (ii) perturbations of AB region (through changes in dynamics of the AB/GH region or abolition of a specific fiber contact site) that influence HbS polymerization do so in concert with alpha78 site at the EF corner. The overall results provide insights about the interaction-linkage between distant regions of the HbS tetramer in fiber assembly.

Status of spermatogenesis and sperm parameters in langur monkeys following long-term vas occlusion with styrene maleic anhydride

Vas occlusion by styrene maleic anhydride (SMA), trade name RISUG (one of the promising male contraceptive procedures currently in phase III clinical trials), at 60 mg/vas deferens dissolved in 120 micro L dimethyl sulphoxide (DMSO) at up to a 540-day study period caused severe oligospermia in the first 2 to 3 ejaculations and uniform azoospermia in the subsequent ejaculations without toxicity in langur monkeys. The ejaculated spermatozoa were necroasthenoteratozoospermic, suggesting instant sterility. Routine hematology and clinical chemistry parameters and the serum testosterone and sperm antibody titers remained unchanged from their pretreatment values until 540 days vas occlusion. Histology of testes revealed continued spermatogenesis throughout the study period. The stages of spermatogenesis appeared normal until 300 days of vas occlusion. At 360 days of vas occlusion, germ cells appeared in the lumen. Degeneration of seminiferous epithelium was evident in some of the tubules. Following 420 days of vas occlusion, the central portion of the testis showed regressed seminiferous tubules depicting various shapes and devoid of germ cells, which continued until 540 days of vas occlusion. Ultrastructure of the testes after 540 days of vas occlusion revealed vacuolization in the cytoplasm of Sertoli cells and degenerative features in the membranes of the spermatocytes and spermatids in the affected seminiferous tubules. The sub-cellular features of the normal tubules were similar to those of controls. The results suggest focal degeneration of seminiferous epithelium in the central portion of the testis following long-term vas occlusion with SMA.

Plants for male fertility regulation

The importance of drugs of plant origin in the pursuit of fertility regulating agents for the male from natural products has long been recognized. This review includes 80 plants with 205 references, up to year 2002. The type of extract, dose, animal model and pharmacological activity of these materials have been reviewed in this paper to add impetus to further research and collaboration to resolve the problem of population explosion.

Chloroform extract of Carica papaya seeds induces long-term reversible azoospermia in langur monkey

AIM

To evaluate the antifertility activity of the chloroform extract of Carica papaya seeds by oral administration in langur monkey, Presbytis entellus entellus.

METHODS

The chloroform extract of Carica papaya seeds, 50 mg/kg/day, was administered orally for 360 days to adult male langur monkeys. The sperm characteristics by light and electron microscopy, the sperm functional tests, the semen biochemistry, the serum testosterone level, the Leydig cell function, and the histology and ultrastructure of testis were determined to evaluate the antifertility activity and the blood biochemistry and hematology, to evaluate the toxicology.

RESULTS

The extract gradually decreased the sperm concentration since days 30-60 of treatment with a total inhibition of sperm motility, a decrease in sperm viability and increase in sperm abnormality. Azoospermia was observed after day 90 of treatment and continued during the whole treatment period. Treatment withdrawal resulted in a gradual recovery in these parameters and 150 days later they reverted to nearly the pretreatment values. Morphological observation of the ejaculated sperm by light and scanning electron microscopy showed deleterious changes, particularly on the mid-piece. Sperm functional tests, viz., sperm mitochondrial activity index, acrosome intactness test and hypo-osmotic swelling test scored in the infertile range during treatment and returned to the fertile values 150 days after drug withdrawal. Histology of the testis revealed shrunken tubules, germ cell atrophy and normal Leydig cells. Ultrastructure of the testis showed vacuolization in the cytoplasm of Sertoli cells and germ cells. Loss of cytoplasmic organelles were evident in the spermatocytes and spermatids. Round spermatids showed loss of Golgi bodies, peripheral mitochondria and vacuolated cytoplasm, indicating maturational arrest. Leydig cell functional test indicated a mild inhibition of steroidogenic function. Haematology and serum biochemistry study disclosed no significant toxicological effect and the serum testosterone level was not affected.

CONCLUSION

Carica papaya seed extract may selectively act on the developing germ cells, possibly mediated via Sertoli cells, leading to azoospermia.

Vas deferens, a site of male contraception: an overview

The vas deferens is a site which can be exploited for male contraception without undue side effects. The only effective technique available for male contraception is vasectomy, being practiced world wide, despite that it is a permanent surgical procedure and its successful reversal is not assured. Although no-scalpel vasectomy minimizes surgical procedures, the fate of its reversal is akin to that of vasectomy. Several occlusive and non-occlusive vasal procedures which claim to be reversible without surgical intervention, possess more disadvantages than advantages. Vas occlusion with plug, 'Shug' or medical grade silicone rubber, although claimed to produce reversible azoospermia without affecting spermatogenesis, requires skilled microsurgery for their implantation and later removal. RISUG, a non-sclerotic polymer styrene maleic anhydride (SMA), could be more advantageous than vasectomy and other vas occlusive procedures in that it could be a totally non-invasive procedure by "no-scalpel injection" and "non-invasive reversal". It is claimed to offer long-term contraception without adverse side effects and also to be possible as a male spacing method by repeated vas occlusion and non-invasive reversal. The drug is currently under multicentre Phase III clinical trial.

Fine structure of the langur monkey vas deferens and possible role of changes following vasectomy in the success or failure of the vasovasostomy

Studies on the ultrastructure of the vas deferens have been carried out in control, vasectomized (6 and 24 months) and vasovasostomized (12 months) langur monkeys (Presbytis entellus entellus Dufresne). Vas deferens epithelium of the control animals depicted four types of cells, viz. the basal cells, principal cells, mitochondria-rich or apical cells and pencil or dark cells. The basal cells were short, cuboidal in nature with prominent nuclei, and contained sparse cytoplasmic organelles. The principal cells were characterized by the presence of nuclei with irregular outline and intranuclear electron-dense granules, well-developed Golgi bodies with prominent secretory vesicles, cisternae of rough endoplasmic reticulum, mitochondria, free ribosome particles, lysosomes and stereocilia in the cytoplasm, suggesting an active secretory role, as well as the absorptive functions of the cells. The mitochondria-rich cells consisted of numerous mitochondria, and other cytoplasmic organelles were sparse. The pencil cells were dark, slightly compressed and situated between the principal cells. Vasectomy resulted in reduction of cytoplasmic volume and vacuolization of the cytoplasm, especially in the Golgi region of the principal cells. Rough endoplasmic reticulum and mitochondria were poorly defined. Vasovasostomy showed no appreciable improvement in the configuration of the cytoplasmic organelles. The results suggest that a persistent reduced secretory activity of the cells following vasectomy and vasovasostomy might also be one of the factors responsible for unsuccessful vasovasostomy.

Reversible azoospermia by oral administration of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in rabbits

Contraceptive efficacy, reversibility and toxicity, if any, of the benzene, chloroform and ethyl acetate chromatographic fractions of the chloroform extract of the seeds of Carica papaya have been investigated in adult male rabbits at a dose regimen of 50 mg/animal/day for 150 days of treatment. Body weight, semen analysis, hematology, serum clinical biochemistry and the fertility status of control and treated animals were evaluated. Chloroform and ethyl acetate chromatographic fractions did not produce appreciable changes in these parameters. However, the benzene chromatographic fraction resulted in uniform azoospermia after 15 days of treatment, which was maintained for the remainder of the 150-day observation period. The levels of fructose, glycerophosphocholine, acid phosphatase and lactate dehydrogenase in the seminal plasma were within the control range. Hematology and the serum clinical parameters showed no appreciable changes, indicating lack of toxicity. The libido of the treated animals was normal and the fertility rate was zero. Complete normalcy of altered parameters was observed 60 days following withdrawal of treatment. It is concluded that the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya possesses reversible male contraceptive potential and the effects appear to be mediated through the testis.

Sterility due to inhibition of sperm motility by oral administration of benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in rats

The contraceptive effects of benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya have been reported in male albino rats at the dose regimens 5 and 10 mg/animal/day; oral for 150 days. The body weight, weight of testis, epididymis, seminal vesicle and ventral prostate remained unaltered during the entire course of the investigation. Total suppression of cauda epididymal sperm motility coincided with a decrease in sperm count, viability and an increase in per cent abnormal spermatozoa during 60-150 days observation period. Minor changes in the germ cell proliferations in the testis and vacuolization and pyknotic nuclei in the few epithelial cells of the cauda epididymis were observed. Histology and biochemical composition of testis and accessory sex organs, haematology and serum clinical biochemistry and serum testosterone levels remained unchanged throughout the course of the investigation. Test for estrogenicity indicated mild estrogenicity. Monthly fertility test showed negative fertility. All the altered parameters returned to normal level following 60 days withdrawal of the treatment. The results suggest that the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya exerts antifertility effects in rats without adverse toxicity and that the effects may be directly rendered on the spermatozoa.

Reversible antispermatogenic effect of gossypol in langur monkeys (Presbytis entellus entellus)

The present investigation reports the antispermatogenic effect of the orally active highly purified gossypol acetic acid at 7.5 mg and 10 mg/day for 180 days in langur monkeys. The results revealed a dose-dependent response in semen analysis as well as testicular morphology. Uniform severe oligospermia was observed in the lower dose (7.5 mg) group, while azoospermia was observed in 2 out of 5 animals in the higher dose (10 mg) group and the remaining animals showed severe oligospermia. Scanning electron microscopy of spermatozoa revealed deleterious abnormalities in the head and midpiece. Testicular morphology revealed a decrease in the seminiferous tubule diameter and arrest of spermatogenesis. The lower dose group had a germ cell population up to primary spermatocytes while the higher dose group had only Sertoli cells and spermatogonia. Withdrawal of treatment for 180 days led to the recovery of all the parameters studied, to normalcy.

Human sperm immobilization effect of Carica papaya seed extracts: an in vitro study

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.

Contraceptive evaluation and toxicological study of aqueous extract of the seeds of Carica papaya in male rabbits

The contraceptive evaluation and toxicological effects of the aqueous extract of the seeds of Carica papaya in adult male rabbits have been reported. Thirty adult male rabbits were divided into five groups of six animals each; Group I, control; Groups II-V were administered orally with aqueous extract of the seeds of C. papaya at doses of 20, 50, 75 and 100 mg/kg per day for 150 days, respectively. The body weight, reproductive organs weight, semen analysis, semen biochemistry, toxicological profiles and the fertility status have been recorded. The aqueous extract failed to exhibit contraceptive effects at any of the dose regimens tested, contrary to the observations made in the previous studies. Unaltered toxicological profiles indicated that the drug was free of side effects. The results suggest that the failure of contraceptive effects may be due to species specificity, relative resistance of the animals to the drug or lack of potency of the extract due to factors generally affect biological activity of the plant preparations.

Ultrastructure of langur monkey epididymidis prior to and following vasectomy and vasovasostomy

The ultrastructural changes in langur monkey epididymis prior to and following vasectomy or vasovasostomy were studied. The epididymal epithelium of the intact langur monkey was found to consist mainly of principal cells and basal cells and frequently apical or mitochondria rich cells were found. Besides these cells intraepithelial lymphocytes were also a consistent feature of the epididymal epithelium. Principal cells identified by means of the tuft of the stereocilia on their apical surface, bear well developed Golgi bodies, endoplasmic reticulum, vesicles, vacuoles and multivesicular bodies. This suggests their active involvement in absorption and secretion. Basal cells present at the base of the lamina bear a few cellular organelles and strong interdigitations with the adjacent cells. Apical or mitochondria rich cells were characterized by clusters of mitochondria in the apical region of the cell and few microvilli on their apical surface. Lymphocytes with a large nucleus and a pale rim of cytoplasm were also found at the base of the epithelium. Secretory and absorptive functions of principal cells of the epididymal epithelium were found to be increased after vasectomy, as indicated by bulging of the apical portion of the principal cells and membrane bound structure in the lumen. An extensive increase in the number of lysosomes, vesicles and vacuoles was also observed. An increase in the number of macrophages with spermatozoa remnants in the lumen of epididymis suggests that the principal mechanism for spermatozoa disposal following vasectomy is intraluminal endocytosis by macrophages. Changes following vasectomy persisted in vasovasostomized animals even after 12 months of recanalization, which may contribute to the failure of functional reanastomosis.

Repeated vas occlusion and non-invasive reversal with styrene maleic anhydride for male contraception in langur monkeys

The feasibility of a spacing method for contraception, using Styrene Maleic Anhydride (SMA) as a vas occlusive agent, has been assessed in male langur monkeys. The vas deferens of 6 animals were occluded with 60 mg SMA in 120 microL DMSO. After 150 days, the occlusion was reversed by a technique which involved palpation, percutaneous electrical stimulation, forced vibratory movement, suprapubic percussion and per-rectal digital massage of the vas segments. The vas deferens were then re-occluded with SMA and reversed by the non-invasive method after three consecutive azoospermic samples. The second vas occlusion resulted in uniform azoospermia after the third ejaculation and reversal caused the reappearance of spermatozoa in the semen to severe oligozoospermic levels in the first two ejaculations and rising to normospermia in the subsequent ejaculations. Ultrastructure of the spermatozoa by SEM and TEM and sperm function tests revealed that the spermatozoa had recovered normal morphology. Vas morphology also regained a normal pseudostratified columnar epithelium containing basal and principal cells. The results suggest that the SMA-based spacing technique for male contraception could be extrapolated to the human by use of no-scalpel injection and non-invasive reversal.

Ultrastructural changes in the vas deferens of langur monkeys Presbytis entellus entellus after vas occlusion with styrene maleic anhydride and after its reversal

Ultrastructural changes in the vas deferens of langur monkeys after 150 days of vas occlusion with styrene maleic anhydride (SMA) and after 150 days of noninvasive reversal are reported. The vas deferens of the sham-operated control animals revealed active secretory and absorptive functions. The basal cells showed prominent nucleus and sparse cytoplasmic organelles, and the principal cells characterized by oval or irregular nucleus, well developed mitochondria, Golgi bodies, rough endoplasmic reticulum, secretory granules in the Golgi area, free ribosomes, and glycogen granules in the supranuclear region suggesting secretory function. Vesicles and stereocilia in the apex region suggested absorptive functions of the vas deferens. Vas occlusion by SMA resulted in exfoliation of epithelial cells, pyknotic nuclei, and vacuolated cytoplasm virtually devoid of cytoplasmic organelles and stereocilia. After noninvasive reversal, the vas epithelium regained a state of normalcy as evidenced by prominent plasma membrane, nucleus, cytoplasmic organelles, and stereocilia. The results suggest that the exfoliation of the epithelium due to vas occlusion by SMA regains normalcy after 150 days of noninvasive reversal.

Reversible contraception with chloroform extract of Carica papaya Linn. seeds in male rabbits

The contraceptive efficacy and reversibility of the chloroform extract of the seeds of Carica papaya in adult male rabbits were investigated. Eighteen adult male rabbits were divided into three groups of six animals each; Group I--control, Group II--administered chloroform extract of the seeds of Carica papaya at 20 mg/animal/d for 150 d by gavage, and Group III--administered the seed extract at 50 mg/animal/d for 150 d. Body weight and organ weight, semen analysis, sperm morphology by scanning electron microscopy, semen biochemistry, histology of the testis, haematology, serum clinical biochemistry, and the fertility status of the control and the treated animals were evaluated. Body weight and the weight of the testis, epididymis, seminal vesicles, and prostate did not show appreciable changes. Sperm concentration showed a gradual decline, reached severe oligospermia (fewer than 20 million/mL) after 75 d treatment, and attained uniform azoospermia after 120 d treatment. Sperm motility and viability were severely affected after 45 d treatment and reached less than 1% after 75 d treatment. The morphology of the spermatozoa by scanning electron microscopy revealed membrane damage in the acrosome, bent midpiece, coiled tail, and detached head and tail. The levels of fructose, glycerylphosphorylcholine, acid phosphatase, and lactate dehydrogenase in the seminal plasma were unaltered. Histology of the testis revealed arrest of spermatogenesis beyond the level of spermatocytes. No toxicity was evident from the haematology and serum biochemistry parameters. The libido of the treated animals was unaffected and the fertility rate was zero. The effects were comparable in both the dose regimens (Groups II and III) and were restored to normal 45 d after withdrawal of the treatment.

Intravasal contraception with styrene maleic anhydride and its noninvasive reversal in langur monkeys (Presbytis entellus entellus)

In male langurs with azoospermia induced by vas occlusion with styrene maleic anhydride (SMA), the exploratory feasibility of azoospermia reversal by a new noninvasive reversal procedure has been assessed. Palpation, percutaneous electrical stimulation of the vas deferens, forced vibratory movement, suprapubic percussion, and per rectal digital massage of the vas deferens are the components of the multimodal noninvasive reversal procedure. The exploratory investigation reveals that a single application of the procedure leads to reversal of azoospermia. Normospermia with normal motility and viability appears after third ejaculation onwards after reversal manipulations. Ultrastructure of the spermatozoa, using scanning and transmission electron microscopy, revealed that the spermatozoa attained normalcy and sperm functional tests (i.e., hypo-osmotic swelling test, slide test for acrosome intactness, and test for sperm mitochondrial activity index) further confirmed the normalcy of the spermatozoa toward their fertilizing ability. Semen biochemistry appeared normal throughout the course of investigation. The morphology of the vas deferens, which showed exfoliation of the epithelium, was in the process of regaining normalcy after 90 days of reversal manipulations. The results suggest that noninvasive reversal technique offers the possibility of the functional azoospermia reversal within a short period of time.

Long-term sequelae of tolnidamine on male reproduction and general body metabolism in rabbits

The long-term effects of tolnidamine on male reproduction and general body metabolism were studied in rabbits (Oryctolagus cuniculus). The study was divided into three groups of 10 animals each. The first group (A) received vehicle alone to serve as controls. The second and third groups (B and C) of animals were administered tolnidamine orally at 50 mg/kg body weight/week and 50 mg/kg body weight/day, respectively, for a period of 150 days. The animals of group B exhibited a sperm density of 23.60 million/mL +/- 4.87 million/mL (vs 453.00 million/mL +/- 65.30 million/mL in group A) after 150 days of treatment. In group C, all animals were azoospermic after 135 days of treatment. A reversible impairment of sperm motility, vitality and morphology was noticed. Semen weight, volume, color, pH, libido, and circulatory levels of testosterone remained unchanged. In group B animals, sperm density did not return to control levels even at 150 days after cessation of treatment (37.40 million/mL +/- 4.46 million/mL, vs 380.00 +/- 40.80 million/mL in group A). However, spermatozoa reappeared in animals treated daily (group C) after 30 days of recovery but remained < 5 million/mL during the entire recovery period. A reversible, significant depletion was recorded in seminal glycerylphosphorylcholine (GPC) levels. Fertility was unimpaired in group B animals when compared with those in group A. In group C, fertility was reduced to zero after 150 days of treatment and at 90 days and 150 days after cessation of treatment. No significant alterations were observed in other semen biochemical, hematologic, or blood/serum biochemical parameters with either dose regimen. It is concluded that tolnidamine administration induced dose dependent, irreversible inhibition of sperm production without altering general body metabolism in male rabbits.

Ultrastructural changes in the spermatozoa of langur monkeys Presbytis entellus entellus after vas occlusion with styrene maleic anhydride

Changes in the physical characteristics of semen and ultrastructure of the spermatozoa of langur monkeys after vas occlusion with styrene maleic anhydride (SMA), a polymer with pH-lowering action, are reported. Vas occlusion resulted in severe reversible hypospermia. Severe oligospermia was observed in the majority of animals (five of eight) in the first ejaculation, 30 days after vas occlusion, and in two animals in the second ejaculation, 60 days after vas occlusion. Subsequent monthly ejaculations for 5 months revealed uniform azoospermia. The voided spermatozoa were immotile and supravital staining confirmed necrospermia. Scanning electron microscopy (SEM) revealed severe coiling of tail, rupture of acrosomal envelope, and bent midpiece associated with damaged mitochondrial sheath. Observations by transmission electron microscopy (TEM) revealed vacuolization in the nucleus, membrane damage in the acrosome, loss of segmented columns, and numeric aberrations in the centriole of the neck, as well as degeneration of mitochondrial sheath and axoneme in the midpiece, and absence of outer plasma membrane in the midpiece and tail. The results indicate that the necrospermic status of the spermatozoa during initial ejaculations may offer instant sterility after vas occlusion with SMA.

Reproductive exocrine and endocrine profiles and their seasonality in male langur monkeys (Presbytis entellus entellus)

The reproductive exocrine and endocrine profiles in male langurs are reported with an emphasis on seasonality. The animals showed positive response to electroejaculation throughout the year. The sperm concentration varied between 10-383 x 10(6)/ejaculation with wide fluctuations all through the year. No appreciable changes in the motility and percent live sperm were observed throughout the year. The levels of seminal fructose and magnesium remained unchanged throughout the year, while acid phosphatase showed wide fluctuations. Citric acid showed elevation during February and March and LDH showed elevated levels during April and May. The annual range of serum testosterone was 6-34 nMol/l with a peak during July. Cortisol ranged between 575-1587 nMol/l and prolactin ranged between 107-900 mU/l. Wide fluctuations were observed in hormonal levels. No seasonality was exhibited in the seminiferous tubule diameter, nuclear diameter of Sertoli cells and Leydig cells, and the cholesterol, glycogen, and sialic acid contents of testis. None of the parameters studied have shown any correlation with season. The results suggest that the male langurs lack seasonality in their reproductive exocrine and endocrine profiles and thus could be used as model for research in human reproduction.

Langur prostate and its hormonal modulation

The normal histoarchitecture of langur prostate of different growth phases, viz., juvenile, sub-adult, and adult, and the hormonal modulation of adult prostate were studied in order to explore its suitability of a surrogate for human prostate. The histological observations revealed that the langur prostate is histoarchitecturally homogeneous. The volumetric composition of stroma (%) was found to be decreased significantly from juvenile to adult and that of epithelium and lumen was found to be increased significantly. The absolute volume (c.c.) of stroma, epithelium, and lumen increased significantly from juvenile to adult. A marked depletion in the various prostatic fluid biochemical parameters was observed in castration groups, which were recovered to control level following testosterone enanthate administration. The castration induced significant increase in volumetric composition of stroma; conversely that of the epithelium and lumen decreased significantly. The absolute volume of stroma did not show any appreciable variation, while that of epithelium and lumen decreased significantly. The inter acinar stroma decreased from juvenile to adult, while the lumen diameter increased significantly from juvenile to adult. Castration increased the inter acinar and lumen diameter; conversely the epithelial height decreased. The testosterone supplementation restored the prostate. However, the volumetric composition of stroma remained high, while the luminal volume remained low. Various prostatic parameters in normal and under altered hormonal conditions suggest that the langur prostate is similar to the human and therefore could be used as surrogate for the human prostate.

Gossypol-induced hypokalemia and role of exogenous potassium salt supplementation when used as an antispermatogenic agent in male langur monkey

In our earlier study, we have observed that hypokalemia in langur monkeys, following gossypol acetic acid (GAA) treatment (5 mg dose level) when used as an antispermatogenic agent, and potassium salt supplementation partially maintained body potassium level of the animals. The aims of the present investigation was to confirm further occurrence of hypokalemia in the monkey (comparatively at two higher dose levels) and the role of potassium salt in preventing occurrence of gossypol-induced hypokalemia. Highly purified gossypol acetic acid alone at two dose levels (7.5 and 10 mg/animal/day; oral) and in combination with potassium chloride (0.50 and 0.75 mg/animal/ day; oral) was given for 180 days. Treatment with gossypol alone as well as with the supplementation of potassium salt resulted in severe oligospermia and azoospermia. Animals receiving gossypol alone showed significant potassium deficiency with signs of fatigue at both dose levels. Enhanced potassium loss through urine was found in potassium-deficient animals, whereas animals receiving gossypol acetic acid plus potassium salt showed normal serum potassium with a less significant increase in urine potassium level during treatment phases. Other parameters of the body remained within normal range except gradual and significant elevation in serum transaminases activity. The animals gradually returned to normalcy following 150 and 180 days of termination of the treatment.

Purified neem (Azadirachta indica) seed extracts (Praneem) abrogate pregnancy in primates

The use of neem (Azadirachta indica) seed extracts (Praneem) given orally for abrogation of pregnancy in subhuman primates is described. Oral administration of Praneem was initiated after confirmation of pregnancy using Leydig cell bioassay estimating rising levels of chorionic gonadotropin (CG) in the blood from day 25 onwards of the cycle and continued for six days. Termination of pregnancy was observed with the appearance of blood in the vaginal smears and decline in CG and progesterone. Pregnancy continued in the control animals treated with peanut oil at the same dose. The effect was observed in both baboons and bonnet monkeys. The treatment was well tolerated; blood chemistry and liver function tests had normal values. The animals regained their normal cyclicity in the cycles subsequent to Praneem treatment.

Antifertility effects of aqueous extract of Carica papaya seeds in male rats

The influence of the crude aqueous extract of Carica papaya L. (Caricaceae) seeds has been studied on semen profile, fertility, body and organ weight response, and toxicology in male albino rats. The extract was administered at the dose regimens of 10 and 50 mg/animal/day orally for 30, 60, and 90 days and 0.1 and 1.0 mg/animal/day intramuscularly for 15 and 30 days. Cauda epididymal sperm motility and count was reduced significantly at low and high dose regimens both in the oral as well as the intramuscular groups. The reduced sperm motility was associated with morphological defects. Testicular sperm counts were also reduced in all the treatment groups except the low dose intramuscular group. Fertility tests showed dose- and duration-dependent reduction and zero fertility was observed at high dose regimens of the oral and intramuscular groups following 60 and 30 days of treatment, respectively. Testicular weight was reduced in all the treatment groups, whereas accessory sex organs showed a variable response. Body weight and toxicological observations did not show any untoward response. Fertility and all other associated changes returned to normal within 45 and 30 days of treatment cessation in the oral and intramuscular groups, respectively. The data revealed that reversible sterility could be induced in male rats by papaya seeds aqueous extract treatment without adverse effects on libido and toxicological profile.

Antifertility investigations on the crude chloroform extract of Carica papaya Linn. seeds in male albino rats

Crude chloroform extract of C. papaya seeds (5 mg/animal/day, po, for 20, 40 and 60 days) was investigated for contraceptive efficacy and related side effects in male albino rats. The crude extract reduced fertility to zero per cent by 40 to 60 days of treatment. Suppression of cauda epididymal sperm motility was the most pronounced effect of the drug administration. Scanning electron microscopic observations revealed treatment induced abnormalities in sperms. Cauda epididymal and testicular sperm counts decreased following treatment. Clinical parameters did not show any alterations. Results suggest that the contraceptive effects of chloroform extract of papaya seeds are mainly post-testicular in nature without influencing toxicological profile and libido of the animals.