ABCC4 is a PGE2 efflux transporter in the ovarian follicle: A mediator of ovulation and a potential non-hormonal contraceptive target.

The role of prostaglandins (PGs) in the ovulatory process is known. However, the role of the ATP binding cassette subfamily C member 4 (ABCC4), transmembrane PG carrier protein, in ovulation remains unknown. We report herein that ABCC4 expression is significantly upregulated in preovulatory human granulosa cells (GCs). We found that PGE2 efflux in cultured human GCs is mediated by ABCC4 thus regulating its extracellular concentration. The ABCC4 inhibitor probenecid demonstrated effective blocking of ovulation and affects key ovulatory genes in female mice in vivo. We postulate that the reduction in PGE2 efflux caused by the inhibition of ABCC4 activity in GCs decreases the extracellular concentration of PGE2 and its ovulatory effect. Treatment of female mice with low dose of probenecid as well as with the PTGS inhibitor indomethacin or Meloxicam synergistically blocks ovulation. These results support the hypothesis that ABCC4 has an important role in ovulation and might be a potential target for non-hormonal contraception, especially in combination with PGE2 synthesis inhibitors. These findings may fill the gap in understanding the role of ABCC4 in PGE2 signaling, enhance the understanding of ovulatory disorders, and facilitate the treatment and control of fertility.

Chemical contraceptive impacts on cyclic progesterone and sexual behavior in zoo-housed Western lowland gorillas.

For regularly cycling primates in captivity, chemical contraceptives can be used to reduce the likelihood of unintentional offspring, but the effects on cyclic progesterone and sexual behavior have not been well studied in gorillas (Gorilla gorilla gorilla). As zoos are invested in maintaining naturalistic behaviors and physiology, this is an important aspect of gorilla physical and mental health. We examined how exposure to combination and progestin-only oral birth control pills altered cyclic progesterone and timing of sexual behaviors in four female gorillas at four institutions compared to cycling controls. Hormonal data were collected using fecal steroid metabolites as detected by enzyme immunoassay. Behavioral data were collected via one-zero sampling done by keeper staff. All methods of oral contraceptive eliminated the ovarian cycle, with fecal progestogens being maintained below baselines in cycling control individuals. There was also no evidence of any cyclic patterning in endogenous progesterone, suggesting that the methods tested do not allow for detection of a recovery of endogenous progesterone during a short no-pill period. We also found that the oral contraceptives altered the timing of behavioral displays when compared to cycling control individuals but was not directly related to any fluctuations in endogenous progesterone. This study reveals a need for additional research on contraceptive use in gorillas and reinforces that sexual behavior in gorillas is both hormonally and socially mediated.

Chronic treatment with hormonal contraceptives alters hippocampal BDNF and histone H3 post-translational modifications but not learning and memory in female rats.

Hormonal contraceptives prevent ovulation with subsequent reduction in endogenous levels of estradiol, progesterone and its neuroactive metabolite allopregnanolone. These neurosteroids modulate several brain functions, including neuronal plasticity, cognition and memory. We hypothesized that hormonal contraceptives might affect synaptic plasticity, learning and memory, as a consequence of suppressed endogenous hormones levels. Female rats were orally treated with a combination of ethinyl estradiol (EE, 0.020 mg) and levonorgestrel (LNG, 0.060 mg) once daily for four weeks. Decreased hippocampal brain-derived neurotrophic factor (BDNF) levels and altered histone H3 post-translational modifications (PTMs) were observed 14 days after discontinuation from chronic EE-LNG treatment. These effects were not accompanied by alterations in long-term plasticity at glutamatergic synapses, recognition memory in the novel object and novel place location tests, or spatial learning, memory, and behavioral flexibility in the Morris water maze test. Thus, decreased BDNF content does not affect synaptic plasticity and cognitive performance; rather it might be relevant for the occurrence of certain psychiatric symptoms, reported by some women using hormonal contraceptives. These results provide the first evidence of hippocampal epigenetic changes induced by hormonal contraceptives and complement previous studies on the neurobiological actions of hormonal contraceptives; the finding that effects of chronic EE-LNG treatment on BDNF content and histone PTMs are observed 14 days after drug discontinuation warrants further investigation to better understand the implications of such long-term consequences for women's health.

Cunninghamella blakesleeana-mediated biotransformation of a contraceptive drug, desogestrel, and anti-MDR-Staphylococcus aureus activity of its metabolites.

Staphylococcus aureus is one of the most infectious agents among staphylococcal bacteria. Currently many strains of S. aureus have developed resistance against available antibiotics. Therefore, the treatment of infections caused by them is a major challenge. During current study, desogestrel (1), a contraceptive drug, was found to be a potent growth inhibitor of drug resistant strains of S. aureus. Therefore, in search of new and effective agents against multi-drug resistant S. aureus strains, whole-cell bio-catalytic conversion of desogestrel (1) by Cunninghamella blakesleeana ATCC 8688A at pH 7.0 and 25 °C was carried out, yielding three new metabolites, 13-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-6ß,15ß,17ß-triol (2), 13-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-3ß,6ß,17ß-triol (3), and 13-ethyl-11-methylene-18,19-dinor-17α-pregn-20-yn-3α,5α,6ß,17ß-tetraol (4), along with a known metabolite, 13-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-6ß,17ß-dihydroxy-3-one (5). Among them, compounds 1-2 showed a potent activity against S. aureus EMRSA-17, S. aureus NCTC 13277 (MRSA-252), and S. aureus NCTC 13143, and clinically isolated Pakistani strain of S. aureus in an in vitro Microplate Alamar Blue Assay (MABA). Vancomycin was used as the standard drug in this assay. In addition, compound 1 also showed a significant activity against vancomycin-resistant S. aureus (VRSA) ATCC 700699. Compounds 1-5 were also evaluated against 3T3 normal cell line (mouse fibroblast) where they all were identified as non-cytotoxic. The present study thus provides new leads for the development of anti-bacterial drugs against MDR S. aureus.

Contraceptive efficacy of recombinant porcine zona proteins and fusion protein encompassing canine ZP3 fragment and GnRH in female beagle dogs.

PROBLEM: To manage population of dogs (Canis familiaris), the efficacy of recombinant proteins-based contraceptive vaccines to inhibit fertility has been evaluated in female beagle dogs. METHOD OF STUDY: Female beagle dogs (n = 4) were immunized with physical mixture of Escherichia coli-expressed recombinant porcine ZP3 with promiscuous T cell epitope of tetanus toxoid (TT-KK-pZP3) and porcine ZP4 with promiscuous T cell epitope of bovine RNase (bRNase-KK-pZP4), or with a fusion protein encompassing dog ZP3 fragment and two copies of GnRH with appropriate promiscuous T cell epitopes (dZP3-GnRH2 ); control animals received only alum, the adjuvant. The immunized animals were followed-up for antibody titres by ELISA as well as for fertility status subsequent to mating with male dogs. RESULTS: Active immunization of female dogs following a three injections schedule at 4-week intervals with a physical mixture of TT-KK-pZP3 + bRNase-KK-pZP4 as well as dZP3-GnRH2 , led to generation of significant antibody titres against respective recombinant proteins. Active immunization with dZP3-GnRH2 also led to generation of antibodies reactive with both dZP3 and GnRH. A booster dose on day 383 led to an increase in antibody titres and circulating antibodies against respective recombinant proteins could be observed on day 528. Antibodies in immune serum samples from dogs immunized with TT-KK-pZP3 + bRNase-KK-pZP4 or dZP3-GnRH2 reacted with native canine ZP as assessed by an indirect immunofluorescence assay. Mating studies revealed a reduced number of pregnancies as well as a significant reduction in the number of pups born in the female dogs immunized with dZP3-GnRH2 as compared to the adjuvanted control. Curtailment of pregnancy in dZP3-GnRH2 immunized group was associated with antibody titres against dZP3-GnRH2 . However, immunization with recombinant TT-KK-pZP3 + bRNase-KK-pZP4 did not significantly decrease the number of pups born as compared to the adjuvanted control. CONCLUSION: These studies revealed the potential of recombinant dZP3-GnRH2 -based contraceptive vaccine to curtail fertility in female dogs. Large scale studies to establish the efficacy and safety of this recombinant protein for the management of community dog population are thus warranted.

Pharmacokinetics, metabolism and serum concentrations of progestins used in contraception.

Many different forms of hormonal contraception are used by millions of women worldwide. These contraceptives differ in the dose and type of synthetic progestogenic compound (progestin) used, as well as the route of administration and whether or not they contain estrogenic compounds. There is an increasing awareness that different forms of contraception and different progestins have different side-effect profiles, in particular their cardiovascular effects, effects on reproductive cancers and susceptibility to infectious diseases. There is a need to develop new methods to suit different needs and with minimal risks, especially in under-resourced areas. This requires a better understanding of the pharmacokinetics, metabolism, serum and tissue concentrations of progestins used in contraception as well as the biological activities of progestins and their metabolites via steroid receptors. Here we review the current knowledge on these topics and identify the research gaps. We show that there is a paucity of research on most of these topics for most progestins. We find that major impediments to clear conclusions on these topics include a lack of standardized methodologies, comparisons between non-parallel clinical studies and variability of data on serum concentrations between and within studies. The latter is most likely due, at least in part, to differences in intrinsic characteristics of participants. The review highlights the importance of insight on these topics in order to provide the best contraceptive options to women with minimal risks.

Immunogenicity and contraceptive efficacy of recombinant fusion protein encompassing Sp17 spermatozoa-specific protein and GnRH: Relevance of adjuvants and microparticles based delivery to minimize number of injections.

PROBLEM: Requirement of multiple injections of contraceptive vaccines to achieve infertility is one of the important impediments for their application. In the present study, attempts have been made to reduce the number of injections of contraceptive vaccine. METHOD OF STUDY: Fusion protein encompassing C-terminus fragment of sperm protein Sp17 (aa residues 76-126) and two copies of gonadotropin-releasing hormone along with T-cell epitopes and dilysine linkers (abbreviated as Sp17C -GnRH2 ) was expressed in Escherichia coli. Its immunogenicity and contraceptive efficacy have been evaluated in female FVB/J mice using different adjuvants and delivery platforms. RESULTS: Immunization of female mice with recombinant Sp17C -GnRH2 (25 µg/injection/mouse) emulsified with squalene-arlacel A following two injections schedule led to failure of 88.8% immunized animals to conceive, which was not significantly different from mice immunized with same protein along with alum following three injections schedule. To make single-dose vaccine, poly d,l-lactic acid-based microparticles (PLA-MPs) entrapping Sp17C -GnRH2 were prepared. Immunization of female mice with a combination of soluble Sp17C -GnRH2 (12.5 µg/injection/mouse) along with Sp17C -GnRH2 entrapped in PLA-MPs (12.5 µg/injection/mouse) in alum showed higher antibody titres and contraceptive efficacy as compared to mice immunized with Sp17C -GnRH2 entrapped in PLA-MPs alone in alum. Immunization with recombinant Sp17C -GnRH2 led to long-term infertility as second mating (150 days after immunization) of various groups of immunized mice showed similar infertility as observed during first mating. CONCLUSION: Single-dose immunization with PLA-MPs entrapping Sp17C -GnRH2 along with soluble recombinant protein in alum generated long-lasting infertility in female mice.

Biotransformation of contraceptive drug desogestrel with Cunninghamella elegans, and anti-inflammatory activity of its metabolites.

Biotransformation of an orally active contraceptive drug, desogestrel (1), with Cunninghamella elegans yielded a new metabolite, 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-17ß-ol-3,6-dione (2), along with five known metabolites, i.e., 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-3ß,6ß,17ß-triol (3), 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-6ß,17ß-diol-3-one (4), 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-17ß-ol-3-one (5), 13ß-ethyl-11-epoxy-18,19-dinor-17α-pregn-4-en-20-yn-17ß-ol-3-one (6), and 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-10ß,17ß-diol-3-one (7). The structure of new metabolite 2 was elucidated by using 1H-, 13C-, and 2D-NMR, EI-, and HREI-MS, IR, and UV spectroscopic data. Compounds 1-7 were evaluated for anti-inflammatory activities, i.e., inhibition of T-cell proliferation, and pro-inflammatory cytokine (TNF-α). Compounds 1 (IC50 = 1.12 ± 0.03 µg/mL), 2 (IC50 = 1.15 ± 0.05 µg/mL), 3 (IC50 = 1.15 ± 0.05 µg/mL), 4 (IC50 = 1.40 ± 0.03 µg/mL), 5 (IC50 = 1.78 ± 0.08 µg/mL), and 6 (IC50 = 1.36 ± 0.07 µg/mL) were identified as potent inhibitors of T-cells proliferation, in comparison to the standard drug, prednisolone (IC50 = 3.51 ± 0.03 µg/mL). Compound 7 (IC50 = 6.18 ± 0.04 µg/mL) showed a good activity. In addition, substrate 1 (IC50 ≤ 1 µg/mL), and its metabolites 2 (IC50 = 4.1 ± 0.60 µg/mL), and 6 (IC50 = 6.8 ± 0.8 µg/mL) also showed a potent inhibition of pro-inflammatory cytokine (TNF-α) production, as compared to the standards drug, pentoxifilline (IC50 = 94.8 ± 2.1 µg/mL). Whereas compounds 3 (IC50 = 57.9 ± 7.6 µg/mL), and 5 (IC50 = 27.2 ± 6.8 µg/mL) showed a moderate inhibition of TNF-α production, while compounds 4 and 7 showed no inhibition. Compounds 1-7 were found to be non-cytotoxic to 3T3 normal cell line (mouse fibroblast).

Nanosilver: a nanoproduct in medical application.

Nanotechnology is a most promising field for generating new applications in medicine. However, only few nanoproducts are currently in use for medical purposes. A most prominent nanoproduct is nanosilver. Nanosilver particles are generally smaller than 100nm and contain 20-15,000 silver atoms. At nanoscale, silver exhibits remarkably unusual physical, chemical and biological properties. Due to its strong antibacterial activity, nanosilver coatings are used on various textiles but as well as coatings on certain implants. Further, nanosilver is used for treatment of wounds and burns or as a contraceptive and marketed as a water disinfectant and room spray. Thus, use of nanosilver is becoming more and more widespread in medicine and related applications and due to increasing exposure toxicological and environmental issues need to be raised. In sharp contrast to the attention paid to new applications of nanosilver, few studies provide only scant insights into the interaction of nanosilver particle with the human body after entering via different portals. Biodistribution, organ accumulation, degradation, possible adverse effects and toxicity are only slowly recognized and this review is focusing on major questions associated with the increased medical use of nanosilver and related nanomaterials.

Absorption of vaginal estrogen cream during sexual intercourse: a prospective, randomized, controlled trial.

OBJECTIVE: To determine if intercourse changed serum estradiol levels in women using vaginal E2 cream or in their male partners. STUDY DESIGN: Prospective, randomized, placebo-controlled, crossover, blinded study of 10 postmenopausal women and their male sexual partners. Subjects were randomized to estradiol or placebo cream and intercourse, then crossed over after 7-14 days. Seven to 14 days later, the woman used vaginal estradiol cream and abstained from intercourse. Serum E2 levels were obtained 10-12 hours after each exposure. RESULTS: Serum E2 levels were higher in 8 of 10 men after intercourse with vaginal estradiol cream, and this resulted in a small but significant (p = 0.03) increase in the estradiol levels as compared to placebo. Paradoxically, intercourse resulted in markedly lower estradiol levels in women as compared to abstinence (p = 0.004). CONCLUSION: Men absorb vaginal estradiol during intercourse, whereas intercourse reduces estradiol absorption in women. Although serum estradiol levels were only mildly elevated in men, it is possible that long-term exposure could cause feminizing changes. In women, estradiol levels were markedly reduced by intercourse.

Contraceptive counseling by gynecologists--which issues are discussed and does gender play a role?

OBJECTIVES: Explorative pilot study with the aim of gaining insight into the contraceptive counseling practices and possible gender differences of a selected group of male and female gynecologists. DESIGN: Semi-structured telephone-interviews of 48 gynecologists concerning the content and strategies of their contraceptive counseling with special focus on aspects relevant to patient adherence. RESULTS: Male and female gynecologists inform equally frequently about various methods and reproductive health aspects such as risks, the advantages and disadvantages of the methods and side effects. Male physicians speak more often about the efficiency and benefits of the methods, while their female colleagues emphasize STI and emergency contraception. Sexual health aspects were seldom mentioned as issues of discussion. For the choice of a contraceptive method efficiency was considered very important by 100%, reversibility by 83%, side effects by 85% and convenience by 79%. Naturalness and costs were more often quoted as important by female, and benefits by male gynecologists. Side effects are considered the most important factor for patient adherence by 60%, counseling and information is predominantly cited by female, and patient's character and personality by male doctors. CONCLUSIONS: While contraceptive counseling by practising gynecologists includes basic information about available methods and their efficiency, as well as some reproductive health issues, sexual health issues are often neglected. Gender differences occasionally influence the choice of the topics as well as the attitude towards the patient.

Strategies to facilitate the development of new contraceptives.

Contraception is not readily accessible to much of the world's population and, in any case, no method is 100% effective or appropriate for all users. There is a pressing need for new methods to address the diverse requirements of the global community of men and women at all stages of their reproductive lives. This article will look at some of the new opportunities in contraceptive research and highlight strategies to overcome old challenges for the development of novel contraceptives.

Biotransformation of drospirenone, a contraceptive drug, with Cunninghamella elegans.

Biotransformation of an orally active contraceptive drug, drospirenone (1), by Cunninghamella elegans ATCC 36114 yielded four new metabolites, 6ß,7ß,15ß,16ß-dimethylene-3-oxo-14α-hydroxy-17α-pregn-4-ene-21,17-carbolactone (2), 6ß,7ß,15ß,16ß-dimethylene-3,11-dioxo-17α-pregn-4-ene-21,17-carbolactone (3), 6ß,7ß,15ß,16ß-dimethylene-3,12-dioxo-17α-pregn-4-ene-21,17-carbolactone (4), and 6ß,7ß,15ß,16ß-dimethylene-3-oxo-11ß,14α-dihydroxy-17α-pregn-4-ene-21,17-carbolactone (5), along with a known metabolite, 6ß,7ß,15ß,16ß-dimethylene-3-oxo-11α-dihydroxy-17α-pregn-4-ene-21,17-carbolactone (6). This study provides not only new analogues of orally active contraceptive drug, drospirenone, but also help in understanding the metabolism of this important drug.

Microbial transformation of contraceptive drug etonogestrel into new metabolites with Cunninghamella blakesleeana and Cunninghamella echinulata.

Biotransformation of a steroidal contraceptive drug, etonogestrel (1), (13-ethyl-17ß-hydroxy-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-3-one) was investigated with Cunninghamella blakesleeana and C. echinulata. Five metabolites 2-6 were obtained on incubation of 1 with Cunninghamella blakesleeana, and three metabolites, 2, 4, and 6 were isolated from the transformation of 1 with C. echinulata. Among them, metabolites 2-4 were identified as new compounds. Their structures were deduced as 6ß-hydroxy-11,22-epoxy-etonogestrel (2), 11,22-epoxy-etonogestrel (3), 10ß-hydroxy-etonogestrel (4), 6ß-hydroxy-etonogestrel (5), and 14α-hydroxy-etonogestrel (6). Compounds 1-6 were evaluated for various biological activities. Interestingly, compound 5 was found to be active against ß-glucuronidase enzyme with IC50 value of 13.97±0.12µM, in comparison to standard compound, d-saccharic acid 1,4-lactone (IC50=45.75±2.16µM). Intestinal bacteria produce ß-glucuronidase. Increased activity of ß-glucuronidase is responsible for the hydrolyses of glucuronic acid conjugates of estrogen and other toxic substances in the colon, which plays a key role in the etiology of colon cancer. Inhibition of ß-glucoronidase enzyme therefore has a therapeutic significance. Compounds 1-6 were also found to be non cytotoxic against 3T3 mouse fibroblast cell lines.

Medroxyprogesterone acetate increases HIV-1 infection of unstimulated peripheral blood mononuclear cells in vitro.

OBJECTIVE: Several observational studies suggest that medroxyprogesterone acetate (MPA) injectable contraceptives may increase a woman's risk of sexual HIV-1 acquisition. In-vitro studies are conflicting, mainly due to differences in the type of progestin studied or activation status of the primary cells. We sought to determine whether MPA increases infection of unstimulated peripheral blood mononuclear cells (PBMCs). METHODS: Freshly isolated PBMCs from normal blood donors were treated with physiologic MPA concentrations ranging from 0.003 to 5 ng/ml and infected with GFP-tagged R5-tropic or X4-tropic HIV-1 pseudoviruses by spinoculation. The infection was limited to a single cycle. Cells were stained with CD3, CD8 and CD14. Infection was quantified as the percentage of GFP cells by flow cytometry. RESULTS: Absolute infection was greater among unstimulated MPA-treated CD3⁺CD8⁻ T cells vs. untreated cells across MPA concentrations of 0.003-3 ng/ml using R5 (P < 0.003) and 0.03-0.3 ng/ml using X4 (P < 0.005) pseudovirus. There was increased relative infection of CD3⁺CD8⁻ T cells in MPA-treated whole PBMC cultures but not after monocytes were depleted (P < 0.02). HIV-1 infection of stimulated PBMC showed no differences in R5 or X4 infection across all MPA concentrations (P > 0.5). CONCLUSION: The CD3⁺CD8⁻ T-cell population of MPA-treated unstimulated PBMCs were more susceptible to HIV-1 infection than untreated cells. The increased infection was partly due to monocytes and was lost when PBMC were exogenously stimulated. These data provide confirmation of a biological association between MPA exposure and increased susceptibility to HIV-1 infection, particularly among women who inject drugs.

Life span extension and cancer risk: myths and reality.

A significant increase in the number of old people in the populations of developed countries was followed by an increase in morbidity and mortality resulting from main age-related diseases -- cardiovascular, cancer, neurodegenerative, diabetes mellitus, decrease in resistance to infections. Obviously, the development of the means of prevention of the premature aging of humans is crucial for the realization of this program. However, data available on such kind of means are rather scarce, contradictory and are often not reliable from the points of view of the adequacy of the experiments to current scientific requirements as well as the interpretation of the results and safety. Data available on the increase in life span and the adverse effects of the following geroprotectors were critically analyzed: antioxidants, chelate agents and lathyrogens, succinate, adaptogens and herbs, neurotropic drugs, inhibitors of monoamine oxidase, glucocorticoids, dehydroepiandrosterone, sex and growth hormones, melatonin, pineal peptide preparations, protein inhibitors, antidiabetic biguanides, thymic hormones and peptides, immunomodulators, enteroadsorbents, lypofuscin inhibitors, as well as calorie intake restriction and special diets. Most of the available results were insufficient and could not provide convincing evidence for the life span extension and the safety of the suggested geroprotectors. Drugs and means prolonging the life span could be subdivided into three groups: (a) geroprotectors prolonging the life span equally in all the members of the population: these postponed the beginning of the population's aging; (b) geroprotectors decreasing the mortality rate in a long-lived subpopulation, which raised their maximal life span: these slowed down the population's aging rate; (c) geroprotectors increasing the survival rate in a short-lived subpopulation without changes in the maximal life span: in this case, the aging rate increased. There was a high positive correlation between the type of geroprotector-induced aging delay and the pattern of tumour development in the same population of animals. The first type of geroprotectors did not influence the incidence of tumour but increased tumour latency. The second type of geroprotectors was effective both in the inhibition of spontaneous carcinogenesis and the increase in tumour latency. Certain drugs of the third type raised tumour incidence in the exposed populations. According to the multistage model, geroprotectors either inhibit or accelerate the passage of carcinogen-exposed cells form one stage to another. Thus, the efficacy of geroprotectors as preventive means of cancer development will decrease with respect to the age of exposure onset. Recommendations of the available drugs and means of life span increase should be carefully reconsidered under the international scientific control.

Identification of bioneutralization epitopes of human follicle stimulating hormone in the regions 31-52 and 66-75 of its beta-subunit.

The crucial role played by follicle stimulating hormone (FSH) in regulating both male and female reproduction and the possibilities of developing contraceptive methods for males by blocking the function of the hormone, makes it important to delineate the hormone-specific bioneutralization epitopes of human follicle stimulating hormone (hFSH) on its beta-subunit. Predictive methods were used to identify the potential surface-oriented regions of hFSH-beta. Peptides corresponding to these regions, i.e. 31-52, 66-75 and 86-95 hFSH-beta, were synthesized, anti-peptide antibodies were elicited in rabbits and the properties of these antisera to bind hFSH and neutralize its biological activity were assessed. Anti-31-52 hFSH-beta antisera bound hFSH specifically, whereas anti-66-75 and anti-86-95 hFSH-beta antisera did not show any detectable binding, proving the region 31-52 hFSH-beta to be a specific antigenic determinant of hFSH. The bioneutralizing abilities of the anti-peptide antibodies were assessed by measuring the hFSH-induced progesterone secretion by rat granulosa cells in vitro. Antibodies to 31-52 and 66-75 hFSH-beta neutralized the bioactivity of hFSH, but anti-86-95 hFSH-beta antibodies did not. Furthermore, the three linear peptides and two disulphide looped peptides of 31-52 hFSH-beta and 86-95 hFSH-beta were also subjected to the in-vitro granulosa cell assay. The linear peptides 31-52 hFSH-beta and 66-75 hFSH-beta and the cyclic 31-52 hFSH-beta disulphide loop peptide significantly inhibited the hFSH-induced progesterone secretion by rat granulosa cells, but the linear 86-95 hFSH-beta peptide and the corresponding cyclic disulphide loop peptide did not. The results clearly show that the regions 31-52 and 66-75 of hFSH-beta harbor bioneutralization epitopes of the hormone. The studies also indicate that cyclization of the linear 31-52 hFSH-beta peptide greatly enhances receptor recognition and that the region 66-75 hFSH-beta may also be involved in hormone-receptor interaction.

Long-acting contraceptive agents: in vitro hydrolysis of esters of norethisterone and levonorgestrel.

The hydrolysis of 108 esters of norethisterone (17 alpha-ethynyl-17 beta-hydroxyestr-4-en-3-one) was studied in vitro using a rabbit liver preparation. Introduction of a double or triple bond into a straight-chain ester did not inhibit hydrolysis but a marked reduction in hydrolysis was produced on replacement of a methylene group by an oxygen atom. Hydrolysis was inhibited by substituents at C2 of the ester chain except in short chain esters. Cyclopropylcarboxylate and cyclobutylcarboxylate were readily hydrolysed and introduction of a furan ring into the side-chain did not affect hydrolysis. No hydrolysis occurred with a cholesteryl carbonate ester or with a pentamethyldisilyloxy ether. Forty-nine esters of levonorgestrel (13 beta-ethyl-17 alpha-ethynyl-17 beta-hydroxygon-4-en-3-one) were also studied. In general, the pattern of hydrolysis for these esters was similar to that of the norethisterone esters. However, with few exceptions the levonorgestrel esters were hydrolyzed more slowly. For those esters for which information regarding the biological activity was available, there was no correlation between the potency of the esters and their rate of hydrolysis in vitro.

[The biotransformation of STS 267 [16 alpha-azido-3-methoxyestra-1,3,5(10)-triene-17-one]. Epimerization of a 16 alpha-azido group--a new metabolic reaction in the rat liver]. / Zur Biotransformation von STS 267 [16 alpha-Azido-3-methoxyestra-1,3,5(10)-trien-17on]. Epimerisierung einer 16 alpha-Azidogruppe--eine neue Stoffwechselreaktion in der Rattenleber.

STS 267 [1; 16 alpha-azido-3-methoxy-estra-1,3,5(10)-trien-17-one] was found to have lipid shifting and fertility inhibitory effects in rats. In preclinical studies the metabolic fate of 1 was investigated in the rat. Demethylation in 3-position, reduction of the 17-carbonyl to the 17 beta-hydroxyl group, and for the first time the epimerization of the 16 alpha-azido to the 16 beta-azido group were established following perfusion of STS 267 in the isolated rat liver. From the perfusion medium 16 alpha-azido-estra-1,3,5(10)-trien-3-ol-17-one (2), 16 alpha-azido-estra-1,3,5(10)-trien-3,17 beta-diol (3), 16 beta-azido-3-methoxy-estra-1,3,5(10)-trien-3,17 beta-diol (4) and 16 beta-azido-estra-1,3,5(10)-trien-3,17 beta-diol (5) as the main metabolite were isolated by TLC and identified by comparison with authentic samples. The extent of the hepatic extraction of 1 in the rat liver was significant lower compared with mestranol.

O uso da pílula anticoncepcional e as alterações das principais vias metabólicas / The use of contraceptive pill and alterations of main metabolic pathways

As pílulas anticoncepcionais são esteroides que visam impedir a gravidez indesejada e regular distúrbios menstruais. Acessíveis em grande variedade no mercado e no SUS, são o método contraceptivo mais aceito pelas mulheres, entretanto trazem diversos efeitos colaterais. O objetivo deste trabalho foi analisar como a pílula anticoncepcional pode alterar as principais vias metabólicas femininas. Trata-se de uma revisão bibliográfica nas bases de dados SciELO, BVS e PubMed, com foco nas correlações entre o uso da pílula anticoncepcional e as alterações metabólicas. Os anticoncepcionais orais atuam na inibição da biossíntese de androgênios e estimulação da SHBG, o que reduz o efeito anabólico proteico. Também promovem o acréscimo dos níveis de LDL-colesterol, colesterol total, PCR-us e dímero D, e alterações na sensibilidade da insulina, no metabolismo do zinco e na hemostasia. Apesar de existirem recomendações que preconizam o uso de outros métodos contraceptivos e estudos que demonstram a satisfação feminina ao trocar os anticoncepcionais orais pelos LARCs, a pílula ainda é a mais utilizada pelas mulheres.(AU)

Contraceptive pills are steroids that prevent unwanted pregnancy and regular menstrual disorders. Accessible in a great variety in market and SUS, they are the contraceptive method most accepted by women, however, they bring several side effects. The objective of this study was analyze how the contraceptive pill can alter the main female metabolic pathways. This is a literature review in the SciELO, BVS and PubMed databases, focusing on the correlations between the use of contraceptive pill and metabolic alterations. Oral contraceptives act to inhibit androgen biosynthesis and stimulate SHBG, which reduces the protein anabolic effect. They also bring about high levels of LDL cholesterol, total cholesterol, CRP, D-dimer, changes in insulin, absence of zinc metabolism and hemostasis. Although there are recommendations that recommend the use of other contraceptive methods and studies that demonstrate the satisfaction of women in exchanging oral contraceptives with LARCs, the pill is still the most used by women.(AU)