Norgestrel causes digestive gland injury in the clam Mactra veneriformis: An integrated histological, transcriptomics, and metabolomics study

The potential adverse effects of progestins on aquatic organisms, especially non-target species, are of increasing concern worldwide. However, the effect and mechanism of progestin toxicity on aquatic invertebrates remain largely unexplored. In the present study, clams Mactra veneriformis were exposed to norgestrel (NGT, 0, 10, and 1000 ng/L), the dominant progestin detected in the aquatic environment, for 21 days. NGT accumulation, histology, transcriptome, and metabolome were assessed in the digestive gland. The bioconcentration factor (BCF) was 386 and 268 in the 10 ng/L NGT group and 1000 ng/L NGT group, respectively, indicating efficient accumulation of NGT in the clams. Histological analysis showed that NGT led to the swelling of epithelial cells and blurring of the basement membrane in the digestive gland. Differentially-expressed genes and KEGG pathway enrichment analysis using a transcriptomic approach suggested that NGT primarily disturbed the detoxification system, antioxidant defense, carbohydrate and amino acid metabolism, and steroid hormone metabolism, which was consistent with the metabolites analyzed using a metabolomic approach. Furthermore, we speculated that the oxidative stress caused by NGT resulted in histological damage to the digestive gland. This study showed that NGT caused adverse effects in the clams and sheds light on the mechanisms of progestin interference in aquatic invertebrates.

In vitro exposure to environmentally relevant concentrations of norgestrel affects sperm physiology and reproductive success of the Pacific oyster Crassostrea gigas

Progestins in aquatic environments are of increasing concern, as shown by the results of toxicological studies on adult invertebrates with external fertilization. However, their potential effects on the gametes and reproductive success of such animals remain largely unknown. Thus, the current study assessed the effect of in vitro exposure of environmentally relevant concentrations (10 ng/L and 1000 ng/L) of norgestrel (NGT) on the sperm of Pacific oyster Crassostrea gigas, analyzing sperm motility, ultrastructure, mitochondrial function, ATP status, characteristic enzyme activities, and DNA integrity underlying fertilization and hatching success. The results showed that NGT increased the percentage of motile sperm by elevating intracellular Ca²⁺ levels, Ca²⁺-ATPase activity, creatine kinase activity, and ATP content. Although superoxide dismutase activity was enhanced to eliminate reactive oxygen species generated by NGT, oxidative stress occurred, as indicated by the increase in malonaldehyde content and damage to plasma membranes and DNA. As a consequence, fertilization rates decreased. However, hatching rates did not alter significantly, possibly as a result of DNA repair processes. This study demonstrates oyster sperm as a useful, sensitive tool for toxicological research of progestins and provides ecologically relevant information on reproductive disturbance in oysters resulting from exposure to NGT.

Synergistic effects of EP-1 and ivermectin mixture (iEP-1) to control rodents and their ectoparasites

BACKGROUND

Ectoparasites of rodents play significant roles in disease transmission to humans. Conventional poisoning potentially reduces the population densities of rodents, however, they may increase the ectoparasite loads on the surviving hosts. EP-1 has been shown to have anti-fertility effects on many rodent species, while ivermectin is effective in controlling ectoparasites. In this study, we examined the combined effects of EP-1 and ivermectin mixture (iEP-1) baits on rodents and their corresponding flea/tick loads.

RESULTS

In males, the weight of testis, epididymis, and seminiferous vesicle were reduced to less than 33%, 25%, and 17%, respectively, compared to the control group following administration of iEP-1 for 7 days. The weight of the uterus increased by approximately 75%. After 5 days of iEP-1 intake, all ticks were killed, whereas 94% of fleas on mice died after 3 days of bait intake. In the field test near Beijing, the flea index was reduced by more than 90% after 7 days of iEP-1 bait delivery. In a field test in Inner Mongolia, the weights of testis, epididymis, and seminiferous vesicle were significantly reduced by 27%, 32%, and 57%, respectively, 2 weeks after iEP-1 bait delivery. Approximately 36% rodents exhibited obvious uterine oedema accompanied by a weight increase of about 150%. The flea index was reduced by over 90%.

CONCLUSION

Our results indicated that iEP-1 is a promising treatment for reducing the abundance of both small rodents and their ectoparasites; this will be effective for managing rodent damage and transmission of rodent-borne diseases associated with fleas and ticks. © 2022 Society of Chemical Industry.

Reproductive effects of synthetic progestin norgestrel in zebrafish (Danio rerio)

The aim of this study was to assess the adverse effects of synthetic progestin norgestrel (NGT) on the reproduction of zebrafish by measuring the egg production, histology and transcriptional expression profiles along the hypothalamic-pituitary-gonadal (HPG) axis in adult zebrafish. After a pre-exposure period of 7 days, adult zebrafish were exposed to 6, 29 and 69 ng L^-1 NGT for 21 days. The results showed that exposure to 69 ng L^-1 NGT led to a significant up-regulation of follicle stimulating hormone, beta polypeptide (fshb), luteinizing hormone, beta polypeptide (lhb), progesterone receptor (pgr), estrogen receptor 1 (esr1) and androgen receptor (ar) genes in the brains, as well as significant up-regulation of hydroxysteroid 20-beta dehydrogenase (hsd20b) and hydroxysteroid 11-beta dehydrogenase 2 (hsd11b2) genes and down-regulation of 11-beta-hydroxylase (cyp11b) gene in the ovaries of females. In the testes of males, an overall down-regulation of steroidogenic acute regulatory protein (star), cytochrome P450-mediated side-chain cleavage enzyme (cyp11a1), cyp11b, hsd20b, hydroxysteroid 17-beta dehydrogenase type 3 (hsd17b3), hsd11b2 and ar genes were observed following exposure to different treatments of NGT. These transcriptional alterations imply that NGT could exhibit the potent progestogenic and androgenic activities in zebrafish. Egg production as well as histology in the ovaries and testes was not affected by NGT. Taken together, the overall results demonstrated that NGT could significantly affect transcriptional expression levels of genes related to HPG axis in zebrafish, and whether that change translates to additional physiological effects is needed further research.

Transcriptional alterations induced by binary mixtures of ethinylestradiol and norgestrel during the early development of zebrafish (Danio rerio)

Synthetic estrogens and progestins are commonly used in human and veterinary medicine. After use, they reach aquatic environments via discharge of wastewaters from human and animals, thus posing potential risks to organisms. So far, very little is known about their combined effects in aquatic organisms. The aim of this study was to investigate the effects of binary mixtures of ethinylestradiol (EE2) and norgestrel (NGT) on embryonic zebrafish (Danio rerio) by measuring transcriptional alterations. Zebrafish embryos were exposed to EE2 and NGT alone or in combination at concentrations between 36 and 5513ngL^-1 for 96h post-fertilization (hpf). The results showed that most of gene transcriptions of hypothalamic-pituitary-gonadal axis (e.g., Pgr, Mprα, Esr1, Esr2a, Vtg1, Ar, Cyp11b, Star, Gnrh3 and Fshb) and circadian rhythm signaling (e.g., Cry1a, Cry2a, Cry2b, Per3, Arntl1b, Arntl2, Clock1a, Cry3 and Cry4) displayed most pronounced alterations in the mixtures as compared to single EE2 and NGT exposures. This finding suggests exposure to the binary mixtures of EE2 and NGT produced significantly enhanced effects in fish as compared to single chemical exposures, and their coexistence could have significant environmental implications.

Molecular action of norgestimate: new developments

BACKGROUND

Acne occurs because the sebaceous glands are overstimulated by high levels of androgens or are hypersensitive to normal levels of testosterone. In women with mild or moderate acne, the association of norgestimate (NG), and ethinyl estradiol (EE) is an effective treatment. This is related to the effect of oral contraceptives on androgen production and transport and the antiandrogenic properties of NG itself.

DESIGN

The present work was undertaken to find out whether NG and its derivative, 17-deacetylnorgestimate(dNG), present steroid activities other than antiandrogen activities, using human progesterone receptor(PR), estrogen receptor α(ERα) and β(ERβ), glucocorticoid receptor(GR) and mineralocorticoid receptor(MR)-responsive cell lines.

RESULTS

We confirmed that NG and its metabolite were progestogen partial agonists (EC50 of 13 and 11.1 nM) and ERα selective agonists (EC50 of 30.4 and 43.4 nM), as well as full antagonists of low affinity for GR (IC50 of 325 and 255 nM) and moderate affinity for MR (IC50 of 81.2 and 83.7).

CONCLUSION

We demonstrated that NG and dNG have full progestogen and weak estrogenic (through ERα) properties, which could explain in part the efficacy of NG in association with EE for the treatment of moderate acne in women. Moreover, their antagonist MR activity might have a favorable impact on cardiovascular risk, atherosclerosis and lipid profiles.

Progesterone and norgestrel alter transcriptional expression of genes along the hypothalamic-pituitary-thyroid axis in zebrafish embryos-larvae

The aim of this study was to investigate the effects of progestins on the hypothalamic-pituitary-thyroid (HPT) axis in the early stage of zebrafish. Zebrafish embryos were exposed to progesterone (P4) or norgestrel (NGT) at 5, 50 and 100 ng L(-1) for 144 h post fertilization (hpf), and the transcriptional levels of target genes along the hypothalamic-pituitary-thyroid axis were determined daily. The results showed that P4 had only minor effects on the mRNA expression of thyroglobulin (Tg), iodothyronine deiodinase type Ι (Dio1) and thyroid hormone receptor β (Thrb) genes. Similarly, the effects of NGT on transcripts of thyrotropin-releasing hormone (Trh), Dio1, iodothyronine deiodinase type II (Dio2) and thyroid hormone receptor α (Thra) genes were generally low. In addition, NGT resulted in some alterations of Tg and Thrb transcripts at different time points. However, a strong induction of Nis mRNA by P4 and NGT was observed in zebrafish embryos-larvae. The overall results showed that besides Nis no effects on the hypothalamic-pituitary-thyroid (HPT) axis are observed following exposure to P4 and NGT, which imply that both P4 and NGT have potential effects on the thyroid endocrine system by inducing transcript of Nis gene during the early stage of zebrafish.

Pharmacokinetics and Pharmacodynamics of a Transdermal Contraceptive Patch and an Oral Contraceptive

This open-label, randomized, 2-way crossover study characterized the pharmacokinetics and pharmacodynamics of a transdermal contraceptive patch and a norgestimate-containing oral contraceptive. Healthy women (n = 34) applied a patch once weekly for 3 consecutive weeks during each of 2 cycles and received an oral contraceptive for 21 consecutive days during each of 2 cycles. Plasma concentrations of norelgestromin and ethinyl estradiol peaked and waned after daily oral contraceptive administration, whereas they rose and reached steady-state levels after first patch application. Norelgestromin exposure was similar; ethinyl estradiol exposure was higher for the patch than oral contraceptive. Hepatic estrogenic activity, assessed by hepatic globulin synthesis, was similar for corticosteroid-binding globulin and corticosteroid-binding globulin-binding capacity and higher for sex hormone-binding globulin for the patch versus oral contraceptive. The clinical significance of the differences in pharmacokinetic and pharmacodynamic profiles between the patch and oral contraceptive is not fully known. No serious adverse events or discontinuations due to adverse events were recorded.

Inhibition of diacylglycerol-sensitive TRPC channels by synthetic and natural steroids

TRPC channels are a family of nonselective cation channels that regulate ion homeostasis and intracellular Ca²⁺ signaling in numerous cell types. Important physiological functions such as vasoregulation, neuronal growth, and pheromone recognition have been assigned to this class of ion channels. Despite their physiological relevance, few selective pharmacological tools are available to study TRPC channel function. We, therefore, screened a selection of pharmacologically active compounds for TRPC modulating activity. We found that the synthetic gestagen norgestimate inhibited diacylglycerol-sensitive TRPC3 and TRPC6 with IC₅₀s of 3–5 µM, while half-maximal inhibition of TRPC5 required significantly higher compound concentrations (>10 µM). Norgestimate blocked TRPC-mediated vasopressin-induced cation currents in A7r5 smooth muscle cells and caused vasorelaxation of isolated rat aorta, indicating that norgestimate could be an interesting tool for the investigation of TRP channel function in native cells and tissues. The steroid hormone progesterone, which is structurally related to norgestimate, also inhibited TRPC channel activity with IC₅₀s ranging from 6 to 18 µM but showed little subtype selectivity. Thus, TRPC channel inhibition by high gestational levels of progesterone may contribute to the physiological decrease of uterine contractility and immunosuppression during pregnancy.

High levels of women's satisfaction and compliance with transdermal contraception: results from a European multinational, 6-month study

OBJECTIVE

To investigate compliance, satisfaction, and preference in women using a transdermal contraceptive patch.

METHODS

Women (18-46 years) from eight European countries used contraceptive patches (norelgestromin 6 mg, ethinylestradiol 600 μg) for six, 4-week treatment cycles. Compliance, satisfaction, and preference were assessed after 3 and 6 cycles and study completion using self-report methods.

RESULTS

Of the 778 participants, 36.8% (n = 287) used no contraception at baseline. The most common methods were oral contraceptives (67.9%, n = 334) and barrier methods (21.5%, n = 106). Of oral contraception users, 63.5% (n = 212) were satisfied or very satisfied with their previous method, but compliance was poor with 77.8% (n = 260) reporting missed doses. After 3 and 6 cycles, >80% of all included women were satisfied or very satisfied with the patch. At study completion, most participants (73.7%) reported a preference for the patch compared to their previous method. Of 4107 cycles, 3718 (90.5%) were completed with perfect compliance. Two pregnancies occurred during this study, representing a Pearl Index of 0.63. No new safety issues were identified and the patch was well tolerated.

CONCLUSION

Women were highly satisfied with transdermal contraception and preferred this form of family planning over their previous method. Transdermal contraception represents a valuable addition to contraceptive options with potential to offer high compliance and efficacy.

[Combined hormonal contraception in cycles artificially extended]

OBJECTIVE

To compare the bleeding patterns, satisfaction and tolerability of 3 different contraceptive in an extended regimens in the service of Family Planning of the North Central Hospital of PEMEX.

MATERIAL AND METHODS

Healthy, adult women with desire of contraception for one year (N 120) were randomly assigned to receive oral contraceptive drospirenone/ethinyl E2 (group1), the norelgestromin/ethinyl E2 transdermal patch (group 2) and vaginal ring etonogestrel/ ethinyl E2 (group 3) in an extended regimen (42 consecutive days, 1 hormone-free week). Study assessments were conducted at scheduled visits at the time of initial screening, at baseline after 1, 3, 6, and 12 months. Subjects recorded menstrual associated symptoms bleeding data and completed satisfaction questionnaires. Subjects and investigators provided overall assessments of the regimens.

RESULTS

Extended use of 3 different contraceptive resulted in fewer bleeding days in every group (66.6%, 55% and 58.3% P 0.0024), and less mastalgia and menstrual pain. Subjects were highly satisfied with three regimens (93.3%, 96.6% and 91.6% P 0.00421). Although not mayor adverse events were reported with this regimen, there was an increase in spotting days; it decreased with each successive cycle of therapy. Efficacy and safety were similar to those reported for traditional cycle.

CONCLUSION

Extended-contraceptive regimen delays menses and reduces bleeding, a profile that may be preferred by women who seek flexibility with their contraceptive method.

The influence of pharmaceutical compounds on male fertility

1. Steroid hormones can affect spermatogenesis and thereby fertility directly and/or indirectly. All antigonadotropically active steroids inhibit spermatogenesis via inhibition of gonadotropin secretion, mainly that of H. Androgens and steroids occurring in the biosynthetic chain of testosterone synthesis have a direct promoting effect on spermatogenesis if applied in high doses. It has not been possible as yet to make clinical use of this positive effect since it is obviously not possible to achieve the necessary intratesticular androgen concentrations. 2. As concerns the different androgens and the steroids in the androgen biosynthetic chain, and also all synthetic anabolics, there is no parallelism between the direct spermatogenic activity, the androgenic activity and the antigonadotropic activity. 3. Estrogens and synthetic gestagens do not inhibit spermatogenesis directly at the testicular level. All effects of estrogens can be abolished experimentally by adequate substitution with gonadotropins or androgens, or a combination of androgens and gonadotropins. 4. Only those antiandrogens inhibit spermatogenesis with additional antigonadotropic properties (e.g. cyproterone acetate). Pure antiandrogens, like flutamide or cyproterone, have a slight and transient influence on spermatogenesis at the most. If at all, they merely cause transient subfertility. 5. Beside steroids and several centrally active pharmaceutics (e.g. psychotropic drugs and several antihypertensive compounds), only siloxanes and methallibur seem to affect spermatogenesis via inhibition of gonadotropin secretion. Other antispermatogenic agents act by inhibition of mitosis (Colchicine, alkylating agents) or presumably via damage of the Sertoli cells. 6. Based on present knowledge, contraception in men could be principally managed by administration of a) androgens alone, b) gestagen/androgen combinations, c) estrogen/androgen combinations, d) certain antiandrogens. 7. The difficulties of contraception in men by steroid hormones or steroid hormone combinations have been pointed out. As regards the usefulness of antiandrogens for contraception, no definite conclusions can be drawn at the moment. All non-steroidal inhibitors of spermatogenesis which have been found up to the present are not suitable because of toxic effects.

Influence of oral contraceptive use on growth hormone in vivo bioactivity following resistance exercise: responses of molecular mass variants

The purpose was to examine effects of oral contraceptive (OC) use on plasma growth hormone (GH) responses to heavy resistance exercise. Sixty untrained women were placed into one of two groups: currently using OC (Ortho Tri-Cyclen) (n=25; mean+/-SD: 24.5+/-4.2y, 160.4+/-7.1cm, 64.1+/-11.3kg) or not currently using OC (NOC) (n=35; 23.6+/-4.6y, 165.9+/-6.0cm, 65.7+/-10.3kg). Participants performed an acute heavy resistance exercise test (AHRET; six sets of 10 repetition squats; 2min rest between sets) during days 2-4 of the follicular phase (NOC group) or of inactive oral contraceptive intake (OC group). Plasma was obtained before and immediately after AHRET and subsequently fractionated based on apparent molecular weight (>60kD, 30-60kD, and <30kD). GH was determined in unfractionated plasma and each plasma fraction using 4 methods: (1) Nichols Institute Diagnostics immunoradiometric assay (Nichols), (2) National Institute of Diabetes and Digestive Kidney Diseases (NIDDK) competitive radioimmunoassay, (3) DSL immunofunctional enzyme-linked immunoabsorbent assay (IFA) and (4) rat tibial line bioassay. GH increased (P<0.05) in all fractions post-AHRET for the Nichols, NIDDK, and IFA. The OC group displayed higher resting GH for the NIDDK, and higher exercise-induced GH for the IFA, Nichols, and NIDDK in unfractionated plasma and >60kD subfraction compared to NOC group. No differences were observed for the tibial line bioassay. OC use augmented immunological GH response to AHRET in unfractionated plasma and >60kD molecular weight subfraction. However, OC use only increased biological activity of GH in one of two bioassays. These data demonstrated that GH concentrations at rest and following exercise are assay-dependent.

Structure-activity relationships of synthetic progestins in a yeast-based in vitro androgen bioassay

The recent identification of tetrahydrogestrinone (THG), a non-marketed designer androgen used for sports doping but previously undetectable by established mass spectrometry-based urine drug screens, and its production by a facile chemical modification of gestrinone has raised concerns about the risks of developing designer androgens from numerous marketed progestins. We therefore have used yeast-based in vitro androgen and progesterone bioassays to conduct a structure-activity study assessing the intrinsic androgenic potential of commercially available progestins and their derivatives, to identify those compounds or structures with the highest risk of forming a basis for such misapplication. Progestins had a wide range of androgenic bioactivity that was not reliably predicted for individual steroids by their progestin bioactivity. 17alpha-Hydroxyprogesterone and 19-norprogesterone derivatives with their bulky 17beta-substituents were strong progestins but generally weak androgens. 17alpha-Ethynylated derivatives of testosterone, 19-nortestosterone and 18-methyl-19-nortestosterone such as gestrinone, ethisterone, norethisterone and norgestrel had the most significant intrinsic androgenicity of all the commercially marketed progestins. Facile chemical modification of the 17alpha-ethynyl group of each of these progestins produces 17alpha-methyl, ethyl and allyl derivatives, including THG and norbolethone, which further enhanced androgenic bioactivity. Thus by using the rapid and sensitive yeast bioassay we have screened a comprehensive set of progestins and associated structures and identified the ethynylated testosterone, 19-nortestosterone and 18-methyl-19-nortestosterone derivatives as possessing the highest risk for abuse and potential for conversion to still more potent androgens. By contrast, modern progestins such as progesterone, 17alpha-hydroxyprogesterone and 19-norprogesterone derivatives had minimal androgenic bioactivity and pose low risk.

Effects of low-dose oral contraceptives on body weight: results of a randomized study of up to 13 cycles of use

OBJECTIVE

To compare the effect of 2 oral contraceptives (OCs) on body weight.

STUDY DESIGN

A randomized, parallel-group, multicenter study of 1,723 women taking an OC with norgestimate (NGM) 180/215/250 microg/ethinyl estradiol (EE) 25 microg vs. 1,171 women taking on OC with norethindrone acetate 1 mg/EE 20 microg for 6-13 cycles was performed. Body weight changes between baseline and cycle 6 and baseline and cycle 13 were analyzed. Analysis included not only changes in mean body weight but also the distribution of changes that were within 5% of baseline weight, 5-10% of baseline weight and > 10% of baseline weight. Only the 10% change was felt to be clinically significant.

RESULTS

The distribution of body weight changes did not statistically differ between the 2 OC groups for any parameter measured. The mean weight change after 6 months for the NGM/EE and norethindrone acetate/EE groups was +0.71 kg and +0.57 kg, respectively. At 13 cycles for the NGM/EE and norethindrone acetate/ EE groups, the mean body weight change was +0.93 kg and +0.62 kg, respectively. Only 0.3% of subjects in both OC groups experienced a 10% change in weight.

CONCLUSION

Use of OCs does not substantially affect body weight for most women.

Effects of levonorgestrel butanoate alone and in combination with testosterone buciclate on spermatogenesis in the bonnet monkey

The spermatogenic effects of levonorgestrel butanoate were studied in adult male bonnet monkeys when administered alone and in combination with testosterone buciclate. Levonorgestrel butanoate (0.25, 1.0 and 2.5 mg kg(-1)) given as two injections on days 0 and 60 (groups II, III, IV) resulted in thickening and folding of the basement membrane and disruption of cell associations in groups III and IV (on day 120). In group II, no apparent changes in testicular histology were observed. When these doses of levonorgestrel butanoate were combined with 40 mg of testosterone buciclate (groups V, VI, VII), maximum changes were seen in group VI in which all stages of spermatogenesis were absent on day 120 except for a small number of spermatogonia. The changes caused by lower dose (group V) and higher dose (group VII) of levonorgestrel butanoate were less prominent than in group VI. A significant decrease in the number of dark A (Ad) and B spermatogonia was observed in all groups except for Ad spermatogonia on day 120 in group V, B spermatogonia on day 60 in group IV and B spermatogonia on day 120 in group III. A significant decrease in pachytene spermatocytes was seen on day 120 in groups V only. Early spermatids showed a significant decrease only in groups V and VII on day 120 of treatment. Advanced spermatids were suppressed significantly in group IV on day 60 and in groups IV and V on day 120. These data indicate that levonorgestrel butanoate (1.0 mg kg(-1)) in combination with 40 mg of testosterone buciclate was the most effective treatment in suppressing spermatogenesis. The site of action of this combination regimen is at the level of renewing Ad spermatogonia.

Ex vivo effect of estrogen and progesterone compared with dexamethasone on cell-mediated immunity of HIV-infected and uninfected subjects

To define the effect of estrogen and progesterone concentrations achieved during hormonal contraceptive therapy (HCT) on cell-mediated immunity (CMI) of HIV-infected and uninfected subjects, peripheral blood mononuclear cells (PBMCs) from varicella-zoster virus (VZV)-seropositive individuals were treated with 0.1 ng/mL of estradiol, 33 ng/mL of norgestrel, and 13 ng/mL of dexamethasone and tested for VZV CMI. Estrogen and progesterone decreased VZV lymphocyte proliferation and T helper (Th) 1/inflammatory cytokine secretion, albeit less than dexamethasone. Progesterone decreased the expression of CD69 activation marker on CD8 and CD14 cells and increased the expression of Fas ligand (CD178) on CD14 monocytes, suggesting that induction of apoptosis may contribute to the inhibitory effect of this hormone. Cytokine production of separated CD4, CD8, and CD14 cells confirmed the effect of progesterone on all 3 cellular types, whereas the effect of estrogen was restricted to CD14 monocytes. The estrogen- and progesterone-mediated inhibition of Th1/inflammatory cytokines was greater in HIV-infected subjects (35% decrease for both hormones) compared with uninfected subjects (12% and 19% for estrogen and progesterone, respectively), whereas the effect on proliferation and PBMC phenotype did not differ by HIV status. Overall, HCT concentrations of estrogen and progesterone downregulated ex vivo VZV CMI of HIV-infected and uninfected subjects.

Antiandrogenic activity of norgestimate in a human androgen-dependent stable-transfected cell line

BACKGROUND

Acne occurs from an overstimulation of the sebaceous glands by high levels of androgens or because sebaceous glands are hypersensitive to normal levels of testosterone. In women with moderate acne, norgestimate (NG) in association with ethinyl estradiol (EE) is acknowledged as an effective treatment; this is related to the effect of oral contraceptives on androgen production and transport. However, the antiandrogenic properties of NG itself have been poorly studied.

DESIGN

The present work was undertaken to find out whether NG and its derivative, 17-deacetylnorgestimate (dNG), present antiandrogen activity. First, we studied the effect of NG and dNG on the intracellular localization of green fluorescent protein (GFP)-labeled androgen receptor (AR). Then, we compared the AR activity of NG and dNG with that of cyproterone acetate (CPA), a gold-standard antiandrogenic compound, by investigating competitive binding, antagonist activity and transactivation level of AR.

RESULTS

NG and dNG decreased GFP-AR nuclear translocation, revealing their antiandrogenic property, as for CPA. In the whole cell competition assay performed in a human cell line stably expressing an AR-responsive luminescent reporter gene (PALM cells) with (3)H-labeled R1881 as tracer, NG and dNG were slightly stronger competitors than the antiandrogen CPA. Half-maximal inhibition (K(i)) of (3)H-labeled R1881 (10(-9) M) binding occurred at 4.2 +/- 0.5 x 10(-8) M of NG, 3.4 +/- 0.4 x 10(-8) M of dNG and 6.6 +/- 0.8 x 10(-8) M of CPA. Comparison of antagonist activities of NG, dNG and CPA on AR transactivation levels showed that NG, dNG and CPA inhibited androgen-induced luciferase activity in PALM cells. We observed slight and similar inhibition with 6 x 10(-8) M respectively of NG, dNG and CPA. For the three compounds, the best inhibitory effect was found at 3 x 10(-7) M: 24% for NG and dNG vs. 47% for CPA. The antiandrogenic activity of NG and dNG was found to be 50% that of CPA.

CONCLUSION

In a human androgen-dependent stable-transfected cell line, a useful tool for studying AR transcriptional activity and its subnuclear localization in the presence of androgens and antiandrogens, we demonstrated that NG and dNG have antiandrogenic properties that could partly explain the efficacy of NG in association with EE for the treatment of moderate acne in women.

Androgenicity of the progestin in oral contraceptives does not affect maximal leg strength

PURPOSE

This study was conducted to examine androgenicity of the progestin in oral contraceptive pills and its effect on maximal leg strength in females.

METHODS

Twelve participants who were using a monophasic pill containing 30 microg ethinylestradiol plus either 150 microg levonorgestrel (LEV) or 250 microg norgestimate (NOR) for at least the last 6 months were recruited (mean+/-SEM; LEV: age, 19.8+/-0.3 years; stature, 1.67+/-0.17 m; mass, 65.9+/-1.9 kg; NOR: age, 20.6+/-0.2 years; stature, 1.65+/-0.17 m; mass, 64.6+/-2.4 kg). Three maximal isokinetic extension and flexion tests were performed on three occasions (Days 3-6, 11-14 and 18-21 of the pill cycle) to assess peak extension and peak flexion torque (in Newton meters).

RESULTS

No significant (p>.05) differences were found in the LEV and NOR groups in peak extension torque (F=0.719; p=.416) or peak flexion torque (F=0.291, p=.601) throughout the pill cycle and between groups.

CONCLUSION

In this small study, the androgenicity of the progestin in the contraceptive pill had no significant association with maximal strength in these female athletes.

Effects of l-norgestrel on the endothelium-dependent relaxation response of rabbit clitoral cavernous smooth muscles

OBJECTIVE

To determine the effect of a popular oral contraceptive, L-norgestrel (a synthetic progestogen), on relaxing response of clitoral cavernous smooth muscles.

DESIGN

Prospective, randomized study.

SETTING

Academic facility.

ANIMAL(S)

Thirty adult female New Zealand White rabbits.

INTERVENTION(S)

We conducted isometric tension studies with norepinephrine, endothelium-dependent (acetylcholine) and endothelium-independent (sodium nitroprusside) vasodilators, and L-norgestrel. The effects of nonspecific nitric oxide synthase inhibitor (N(w)-nitro-L-arginine methyl ester) and the potassium channel blockers (1 and 10 mM tetraethylammonium as well as 10 microM glibenclamide) on the reactivities of clitoral cavernous strips were investigated.

MAIN OUTCOME MEASURE(S)

Causation and power of developed tension after treatment.

RESULT(S)

Acetylcholine, sodium nitroprusside, and L-norgestrel produced concentration-dependent relaxation of the norepinephrine-precontracted strips. Both endothelium removal and treatment with 10 microM N(w)-nitro-L-arginine methyl ester completely inhibited the relaxation response to acetylcholine and L-norgestrel, and supplementation with 10 mM L-arginine partially reversed the inhibition. Incubation with either tetraethylammonium (TEA) or glibenclamide reduced the L-norgestrel-induced relaxation in a dose-independent manner.

CONCLUSION(S)

The L-norgestrel-induced relaxation of the clitoral cavernous smooth muscle is endothelium and nitric oxide dependent and may be related to more than two types of potassium channels activation.

Clinical study comparing the effects of sequential hormone replacement therapy with oestradiol/dydrogesterone and conjugated equine oestrogen/norgestrel on lipids and symptoms

A clinical study comparing the effects of sequential hormone replacement therapy with oestradiol/dydrogesterone and conjugated equine oestrogen/norgestrel on lipids and symptoms.

OBJECTIVE

The objective of the study was to compare the effects of sequential 17beta-oestradiol/dydrogesterone and conjugated equine oestrogens (CEE)/norgestrel on lipid parameters, climacteric symptoms, bleeding patterns and tolerability.

STUDY DESIGN

This double-blind study was conducted in 193 peri- and post-menopausal women randomised to receive six, 28-day cycles of oral sequential oestradiol 1 mg/dydrogesterone 10 mg or CEE 0.625 mg/norgestrel 0.15 mg. The change from baseline in serum lipids and hot flushes was analysed using a two-way analysis of variance.

RESULTS

After 24 weeks there was a statistically significant increase in high-density lipoprotein (HDL) cholesterol in the oestradiol/dydrogesterone group and a significant reduction in the CEE/norgestrel group. The difference between the groups was significant (P=0.001). The number of hot flushes was reduced by 86% in both groups; this improvement was supported by the Greene Climacteric Symptom Scale score, the patients' opinion and quality of life assessments. The percentage of women experiencing cyclic bleeding was greater with CEE/norgestrel, as was the mean duration and severity of bleeding. Both treatments were well tolerated.

CONCLUSION

Oestradiol/dydrogesterone and CEE/norgestrel were equally effective in treating climacteric symptoms, but oestradiol/dydrogesterone showed some advantages in terms of lipid profile and incidence of bleeding.

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.

Interaction of progestins with the human multidrug resistance-associated protein 2 (MRP2)

Progestins are widely used as oral contraceptives and hormone replacement therapy. Recently it has been demonstrated that many progestins are inhibitors of P-glycoprotein, possibly explaining gender differences in drug actions. In vitro evidence suggested that at least norgestimate might also inhibit other transporters like the multidrug resistance-associated protein 2 (MRP2). We therefore investigated whether norgestimate, desogestrel, medroxyprogesterone acetate, norethisterone, progesterone, cyproterone acetate, chlormadinone acetate, and levonorgestrel inhibit MRP2 in vitro using confocal laser scanning microscopy and 5-chloromethylfluorescein diacetate as a prodrug of the fluorescent 5-chloromethylfluorescein (CMF), which is actively transported by MRP2 as glutathione conjugate. Of the progestins tested, only norgestimate (50 microM) and progesterone (100 microM) significantly increased intracellular CMF fluorescence by 62% and 53%, respectively. In conclusion, the progestins norgestimate and progesterone significantly inhibit the transport activity of MRP2 in vitro.

Norelgestromin/ethinyl estradiol transdermal system

The transdermal contraceptive patch is an innovative contraceptive technology. The failure rate is quite low and has high continuation rate. The side effects and complications are not different from other hormonal contraceptives. This contraceptive method should be an alternative birth control technique for women.

Effects of an oral contraceptive (norgestimate/ethinyl estradiol) on bone mineral density in women with hypothalamic amenorrhea and osteopenia: an open-label extension of a double-blind, placebo-controlled study

OBJECTIVE

The effects of long-term triphasic oral contraceptive administration on bone mineral density (BMD) were investigated in premenopausal women with hypothalamic amenorrhea (HA) and osteopenia.

METHODS

After completing three 28-day cycles in the double-blind phase of a placebo-controlled trial, women (mean age, 26.7 years) who received norgestimate 180-250 microg/ethinyl estradiol 35 microg (NGM/EE, n = 15) or placebo (n = 12) in the double-blind phase were to receive open-label NGM/EE for 10 additional cycles.

RESULTS

For subjects completing > or =10 NGM/EE treatment cycles, mean posteroanterior total lumbar spine BMD (L1-L4) increased from 0.881+/-0.0624 g/cm2 at baseline (last visit prior to NGM/EE) to 0.894+/-0.0654 g/cm2 at final visit (p = .043); no significant changes in hip BMD occurred. Decreases in N-telopeptide, osteocalcin, procollagen type I propeptide and bone-specific alkaline phosphatase levels indicated effects on bone metabolism.

CONCLUSIONS

Long-term administration of triphasic NGM/EE to osteopenic women with HA may increase total lumbar spine BMD.

Effect of oral versus transdermal steroidal contraceptives on androgenic markers

OBJECTIVE

The purpose of this study was to compare biochemical androgen profiles in women treated with the contraceptive patch versus an oral contraceptive (OC).

STUDY DESIGN

Twenty-four healthy women were randomly assigned to receive 3 cycles of either the contraceptive patch (ethinyl estradiol [EE] 20 microg/d and norelgestromin 150 microg/d) or OC (EE 35 mug and norgestimate 250 microg). Blood samples were taken at baseline and end of treatment. Serum levels of sex hormone-binding globulin (SHBG), total testosterone (T), androstenedione (A), dehydroepiandrosterone sulfate (DHEAS), dihydrotestosterone (DHT), and 3alpha-androstanediol glucuronide (3alpha-diol G) were quantified by immunoassay methods; free T was calculated. The paired t and Student t tests were used for statistical analysis.

RESULTS

Nineteen women completed the study (patch, n = 10; OC, n = 9). Despite a 1.6-fold relative increase in SHBG levels with the patch versus OC (449% vs 274%, P = .03), free T decreased equally in both groups (patch 60%, P < .0001; OC 59%, P < .0001). DHEAS decreased by 26% in the patch group (P < .01) and 32% in the OC group (P < .001). 3alpha-diol G was reduced by 52% in the patch group (P < .0001) and 51% in the OC group (P < .0001). In addition, the OC was associated with significant decreases in A and DHT.

CONCLUSION

The contraceptive patch had an effect comparable to the OC on several key androgenic markers. Given these biochemical findings, the contraceptive patch has significant potential as a therapeutic agent for disorders of androgen excess.

The effect of continuous oestradiol with intermittent norgestimate on bone mineral density and bone turnover in post-menopausal women

OBJECTIVE

To assess in post-menopausal women the efficacy and tolerability of a continuous oestradiol/intermittent norgestimate HRT regimen to prevent and to reverse post-menopausal loss of bone mineral density (BMD) and to determine the effects on serum bone turnover markers markers.

METHODS

A 1-year, multicentre, international, placebo-controlled, randomised, double-blind clinical trial was conducted in 146 post-menopausal women with an intact uterus in order to assess the effect on bone loss of continuous oral 17beta-oestradiol (1 mg per day) combined with norgestimate (90 microg per day), for 3 consecutive days out of every 6-day treatment period (E2/iNGM). During a second year extension, all women agreeing to continue were on the E2/iNGM regimen. BMD was assessed prior to treatment and after 1 and 2 years or at the end of treatment in women stopping participation prematurely after at least 6 months of treatment. Serum bone turnover markers were determined prior to and at 1 year of treatment Adverse events were collected at three-monthly intervals during clinic visits over the treatment period.

RESULTS

BMD in the lumbar spine, the primary endpoint, was evaluable in 117 subjects completing >6 months of treatment. BMD increased on average by 2.4% in women on the intermittent progestin regimen. It decreased by 1.4% in placebo treated women. The change from baseline and the difference between active and placebo treatment (Delta placebo) were highly significant (P < 0.0001). On E2/iNGM, also the BMD in the total hip increased (+1.49%, Delta placebo 3.73%, P < 0.0001). The serum markers for bone formation osteocalcin and type I collagen N-propeptide were significantly reduced compared to baseline by 31 and 44%, respectively and the bone resorption marker C-terminal crosslinked telopeptide of type I collagen by 59%. Minor increases (<10%) of markers in the placebo group were not significant. During a second year extension of the trial, all subjects were on active treatment. Subjects on placebo who lost (median+/-CI 95%) 0.66% (-2.3 to +0.5) of spine BMD during the first year now gained 4.41% (2.7-7.6). They also gained 1.6% (0.1-0.3.6) in the total hip. Subjects continuously on oestradiol/intermittent norgestimate (E2/iNGM) gained an additional 5.7% (2.3-13.5) in the lumbar spine and +0.1% (-0.6 to +2.2) at the total hip. Side effects reported by women on the intermittent progestin regimen significantly in excess over reports from the placebo group were uterine bleeding, abdominal and breast pain, but not headache. Back pain and weight gain was reported by significantly fewer women on active treatment compared to placebo.

CONCLUSION

The continuous oestradiol/intermittent norgestimate HRT regimen is well tolerated, reduces bone turnover and prevents post-menopausal bone loss in healthy post-menopausal women.

Visual sensitivity across the menstrual cycle

This study was designed to evaluate the hypothesis that hormonal change can affect lower level light-adaptation processes, which are likely to be retinally based. Foveal visual sensitivities were measured across several menstrual cycles of four women not using hormonally acting medication and across several menstrual cycles of three women using a triphasic oral contraceptive. One woman, diagnosed with premenstrual syndrome (PMS), was a subject for both groups. Sensitivities were measured for a series of test wavelengths for 580-nm backgrounds of 2.0 and 4.0 log td. Of the six individuals tested, one had clear evidence of visual-adaptation changes occurring in phase with the menstrual cycle. Prior to using the oral contraceptive, this individual (the PMS subject) experienced changes of short-wavelength-sensitive (SWS)-cone-mediated sensitivities of up to about 1.4 log unit on the 4.0 log td background. Her SWS-cone-mediated sensitivities tended to be highest near ovulation and lowest premenstrually. Threshold-versus-illuminance (TVI) curves confirmed that the rate of sensitivity decrease with increasing background illuminance (i.e. the TVI slope) was greater premenstrually. The degree of background-induced desensitization within her middle-wavelength-sensitive (MWS)/long-wavelength-sensitive (LWS) cone pathways also appeared to vary cyclically, but the magnitude of the variation was smaller and the time course appeared to be different. When this subject began oral contraceptive use, the patterns of sensitivity change were all altered. None of the other five subjects experienced changes of SWS-cone-mediated vision that were cyclic and significantly adaptation-state dependent. However, there was evidence for a limited degree of cyclic adaptation change within the MWS/LWS cone pathways of at least one additional subject. We conclude that hormonal change can--for some unknown proportion of women--be linked to alterations of retinal function. However, the alterations are not the same for all visual pathways, and there are pronounced individual differences. The data also demonstrate that individuals' visual adaptation capabilities can vary substantially over periods of weeks.

Norgestimate and medroxyprogesterone acetate do not attenuate the atheroprotective effects of 17beta-estradiol in ovariectomized, apolipoprotein E-deficient mice

OBJECTIVE

To determine whether progestins counteract the cardioprotective effects of estrogen.

DESIGN

Controlled animal study.

SETTING

Academic laboratory environment.

ANIMAL(S)

Female apolipoprotein E-deficient mice.

INTERVENTION(S)

Mice were randomly assigned to groups receiving a sham operation plus placebo pellet, bilateral gonadectomy plus placebo pellet, or gonadectomy plus one of nine combinations of estrogen/progestin SC pellets.

MAIN OUTCOME MEASURE(S)

Total plasma cholesterol, body weight, fat depot weight, uterine weight and size, and the cross-sectional area of fatty streaks in the aortic sinus were measured in each animal.

RESULT(S)

After 8 weeks of treatment, plasma cholesterol levels were significantly higher only in the ovariectomized and sham-operated animals that received placebo pellets. No differences in plasma cholesterol were observed relative to the type or amount of progestin administered. There was a reduction in fatty streaks in all of the hormone treatment groups as compared with both the ovariectomized and sham-operated animals that received placebo pellets.

CONCLUSION(S)

There were no significant differences in lesion area in response to estrogen alone or to estrogen plus the different types and doses of progestins.

Ovarian follicular development is initiated during the hormone-free interval of oral contraceptive use

We evaluated ovarian follicular development in women during compliant use of oral contraceptives (OC). Thirty-six healthy women received: [35 microg ethinyl estradiol (21)/180 microg norgestimate (7), 215 microg norgestimate (7), 250 microg norgestimate (7)]; [30 microg ethinyl estradiol (21)/150 microg desogestrel (21)]; or [20 microg ethinyl estradiol (21)/100 microg levonorgestrel (21)] for 3 consecutive 28-day cycles. Transvaginal ultrasonography was performed every third day to monitor follicular development. If a follicle reached > or = 14 mm, ultrasonography was performed daily and blood drawn every other day to determine estradiol-17beta concentrations. Seventeen of 36 women (47%) grew follicles > or = 10 mm. Nine of the 17 women (53%) grew follicles > or = 14 mm, in association with increased serum concentrations of estradiol-17beta. Thirty-seven of 43 follicles > or = 10 mm (86%) emerged during the hormone-free interval (HFI). No ovulations were observed. Our results supported the hypothesis that follicular development to an ostensibly ovulatory diameter occurs during compliant OC use, in association with loss of endocrine suppression during the HFI.

Induction of androgen receptor activity by norgestimate and norelgestromin in MDA-MB 231 breast cancer cells

The function and clinical significance of the androgen receptor (AR) in human breast cancer are still not clear. The synthetic progestins, norgestimate and norelgestromin, were designed to minimize the adverse effects such as acne, hirsuitism and metabolic changes observed with older oral contraceptives while maintaining contraceptive effectiveness and cycle control. AR-mediated effects of these synthetic progestins were studied in an in vitro transactivation assay, employing DNA co-transfection of an AR expression vector and luciferase reporter gene construct in the MDA-MB 231 human breast cancer cell line. Testosterone acetate and 5alpha-dihydrotestosterone induced the reporter gene transcription, whereas incubation of the transfected cells with the natural progestin 17alpha-hydroxyprogesterone did not markedly induce luciferase activity. The progestins norgestimate and norelgestromin exerted a very low androgenic activity. Our data suggest that norgestimate and its metabolite norelgestromin possess weak androgen-like properties. The use of these compounds for clinical application may be of great advantage in the treatment of breast cancer as well as hyperandrogenism in women.

Augmented endothelial nitric oxide synthase (eNOS) protein expression in human pregnant myometrium: possible involvement of eNOS promoter activation by estrogen via both estrogen receptor (ER) and ER

The aim of the present study was to investigate the possible contribution of estrogen to pregnancy-associated modulation of nitric oxide production in the human myometrium during pregnancy. Both endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) proteins were clearly expressed in the non-pregnant myometrium and were elevated in the first trimester of pregnancy. Oral contraceptive pills augmented eNOS, but not iNOS, protein expression in the non-pregnant human myometrium. In cultured human myometrial cells, estrogen receptor (ER)alpha and ERbeta expression was extremely low. Therefore, we used either ERalpha or ERbeta expression vector to investigate the effect of 17beta-estradiol treatment on eNOS promoter activity using eNOS promoter/luciferase vector in cultured human myometrial cells. 17beta-estradiol treatment significantly augmented eNOS promoter activity in cells co-transfected with either ERalpha or ERbeta, and this augmentation was dose-dependently suppressed by ICI 182780, an estrogen antagonist. These data suggest the possibility that both ERalpha and ERbeta are involved in the estrogen-associated regulation of eNOS gene expression in the human myometrium.

Identification of CRASH, a gene deregulated in gynecological tumors

We have identified CRASH, a human asparaginase-like protein which is composed of 308 amino acids and exhibits 32% homology to human aspartylglucosaminadase at the amino acid level. Database analysis revealed that the gene corresponding to CRASH is composed of 7 exons and 6 introns. Steady-state level of CRASH mRNA was found to be increased in 5 cell lines derived from metastatic lesions compared with 2 cell lines derived from primary mammary carcinoma and HMEC (human mammary epithelial cells). We found that the mRNA level of CRASH correlates with the metastatic propensity of several isogenic human colon cancer and pancreatic carcinoma cell lines. CRASH corresponds to a recently identified sperm autoantigen and furthermore we have demonstrated inducibility of CRASH mRNA by androgen and progesterone. Investigation of several types of human cancers and their corresponding normal tissues revealed high levels of CRASH mRNA in uterine, mammary and ovarian tumors compared with the corresponding normal tissues. CRASH mRNA expression was analysed in breast cancer samples with disclosed clinico-pathological features and corresponding normal tissues. The levels of CRASH mRNA were significantly up-regulated in tumors compared with normal breast tissues and correlate with lack of estrogen receptor expression of the tumors.

Matrix metalloproteinase 2 and tissue inhibitor of metalloproteinase 2 expression is not regulated by norgestimate or norelgestromin

Steroid hormones regulate endometrial expression of matrix metalloproteinases (MMPs) and their inhibitors. Synthetic progestins are widely used in oral contraceptives and for hormone replacement therapy. To assess whether the synthetic progestins norgestimate and its derivative norelgestromin (17-deacetylnorgestimate) modulate the expression of MMPs, Ishikawa endometrial cancer cells were separately treated with 17 beta-estradiol, 17 alpha-hydroxyprogesterone, norgestimate and norelgestromin. Culture supernatants were assayed for MMPs 2, 3 and 9, and for tissue inhibitors of MMPs (TIMP-1 and TIMP-2) by enzyme-linked immunosorbent assays (ELISAs). No marked modulation of MMP-2 and TIMP-2 expression was observed upon incubation of the cells with the synthetic progestins. By ELISA, neither MMP-3 or MMP-9 nor TIMP-1 immunoreactivity was detected. Interestingly, TIMP-2 expression was down-regulated by 17 beta-estradiol and 17 alpha-hydroxyprogesterone.

Rationale for new oral contraceptive dosing

The evolution of both the type and dose of the estrogen and the progestin in oral contraceptives has been complex. Whereas the evolution of the progestin component remains dominated by a concern for the metabolic effects of the 19-nortestosterone derivatives, the evolution of the estrogen component has been more of a concern for safety, or perceived safety. By lowering the estrogen dose, some side effects, such as breast tenderness, bloating and nausea, have decreased. At the same time, others, such as breakthrough bleeding and spotting (BTB/BTS), have increased. Indeed, BTB and BTS are the chief reason why women discontinue OCs as well as the primary reason clinicians change the dose or brand of an OC. During the past few years numerous studies have shown inferior cycle control with 20-microgram ethinyl estradiol (EE) OC formulations compared to slightly higher dose OCs. Recently marketed OCs containing 25-30 micrograms of EE have addressed this issue. The 25-microgram EE OCs combined with desogestrel have cycle control equal to a 35-microgram EE OC, whereas the 25-microgram OC combined with norgestimate has shown superior cycle control compared to a 20-microgram EE OC. The 30-microgram EE OC combined with drospirenone in a non-comparative trial is also associated with low rates of BTB/BTS. Our current goal, now that safety issues have been put to rest, is that of identifying formulations that will enhance adherence and increase successful use of OCs.

Steroid hormone regulation of the human kallikrein 10 (KLK10) gene in cancer cell lines and functional characterization of the KLK10 gene promoter

BACKGROUND

The human kallikrein 10 (KLK10) gene is a new member of the human tissue kallikrein gene family. It encodes for a secreted serine protease (hK10) with predicted trypsin-like enzymatic activity. KLK10 is highly expressed in the sex organs and its expression level changes in malignancy.

METHODS

To determine the role of steroid hormones in KLK10 gene expression, we investigated its modulation by 17beta-estradiol, 5alpha-dihydrotestosterone, norgestrel, dexamethasone and aldosterone, at both the transcription and translation level, in a panel of cancer cell lines. After steroid hormone stimulation, the change of KLK10 mRNA was monitored with reverse transcriptase polymerase chain reaction and hK10 protein levels in the culture supernatant were quantified with an hK10-specific immunoassay. The presence of hormone response elements in the KLK10 gene promoter was examined with the chloramphenicol acetyltransferase reporter gene system.

RESULTS

The KLK10 expression was mainly up-regulated by estrogens, androgens and progestins, and to a lesser extent by dexamethasone and aldosterone in the breast cancer cell lines BT-474, MCF-7 and T-47D, both at the mRNA and protein levels. The effect of stimulation of these steroids on KLK10 expression varied among the cell lines. Estrogens, androgens and progestins were most potent in the BT-474, T-47D and MCF-7 cells, respectively. The up-regulation effect of estrogens, androgens, and progestins on KLK10 expression can be blocked by their antagonists ICI-182, 780, RU-56,187, and mifepristone, respectively. Time course studies showed that hK10 protein started to increase 1 day after steroid hormone stimulation and this increase persisted for 7 days. These data suggest that steroid hormones up-regulate KLK10 gene expression through direct interaction between hormone-receptor complexes and their cognate hormone response elements. To search for hormone response elements, we functionally characterized the KLK10 promoter by placing it upstream of the chloramphenicol acetyltransferase reporter gene. We found that KLK10 promoter activity did not rely on the presence of functional estrogen and androgen receptors. Also, the presence of functional estrogen and androgen receptors did not increase its constitutive activity. We suggest that the hormone response elements that mediate the transcriptional regulation of KLK10 are unlikely to locate in the KLK10 promoter.

CONCLUSIONS

Estrogens, androgens and progestins modulate KLK10 expression through their own receptors but this regulation is not mediated by steroid hormone response elements in the promoter of the KLK10 gene.

Effect of progestin-only pill on pituitary-ovarian axis activity during lactation

We have monitored effects of progestin-only pill (POP) on ovarian activity during breastfeeding. Twenty-one women, using barrier methods (BM) of contraception and 9 women on POP were enrolled 6 weeks postpartum (PP) and followed-up to 18 weeks PP. There was little change in plasma follicle-stimulating hormone and luteinizing hormone, and no differences between BM and POP. POP did not affect plasma estradiol. There was no difference between BM and POP in plasma inhibin B concentrations. The size of follicles was similar in both groups in all time points. There was an increase in the endometrial thickness from 6 weeks PP to 18 weeks PP in BM (3.7 +/- 0.5 vs. 5.4 +/- 0.6 mm, p < 0.05), but no differences within the POP group or between the treatment groups. POP does not suppress gonadotropins nor affect growth of ovarian follicles during breastfeeding. Thus, the contraceptive effect of POP is likely mediated through local actions at the endometrium and cervix in a manner similar to that in menstruating women.

Oral contraceptives improve lung mechanics

OBJECTIVE

To determine whether oral contraceptives affect lung mechanics.

DESIGN

Open-label study.

SETTING

Academic medical center.

PATIENT(S)

Thirty-six healthy nonsmoking women.

INTERVENTION(S)

Administration of an oral contraceptive containing ethinyl estradiol, 35 microg, and norgestimat, 250 microg for 6 months.

MAIN OUTCOME MEASURE(S)

Forced vital capacity; forced expiratory volume in 1 second; peak expiratory flow; and flow at large, medium, and small lung volumes.

RESULT(S)

At 6 months, all forced expiratory flow and volume had increased significantly (from 6.5% to 15%). Flows at small lung volumes especially increased.

CONCLUSION(S)

Combination oral contraceptives have a measurable effect on lung mechanics.

Serum distribution of the major metabolites of norgestimate in relation to its pharmacological properties

Norelgestromin (NGMN) and levonorgestrel (LNG) are the main active metabolites of norgestimate (NGM), but their relative contributions to the pharmacological effects of NGM are unclear. We have therefore determined the serum distribution of these NGM metabolites and assessed their steady-state concentrations in women following >or=3 cycles of oral contraceptive (OC) use. The administration of 250 microg NGM/35 microg ethinyl estradiol (EE) resulted in significantly higher sex hormone-binding globulin (SHBG) levels (p = 0.002), and 30% lower serum non-protein-bound (NPB) levels of testosterone, when compared to treatment with 150 microg LNG/30 microg EE. We also confirmed that NGMN does not bind to SHBG, and found that 97.2% of this metabolite is bound to albumin while only 2.8% is in the NPB fraction. In contrast, most of the LNG was bound to SHBG (92.5% and 87.2% after NGM/EE and LNG/EE treatment, respectively), and the NPB fraction of LNG (0.7%) during NGM/EE treatment was lower (p < 0.001) than during LNG/EE treatment (1.4%). Combining these serum distributions with the C(max) and AUC(0-24h) data obtained after NGM/EE treatment gave NPB and albumin-bound values of NGMN that were much greater than the corresponding LNG values. Furthermore, the C(max) and AUC(0-24h) values for NPB LNG during NGM/EE treatment were estimated to be lower than during LNG/EE treatment. Since LNG is primarily bound by SHBG, its access to target tissues is restricted. Moreover, because SHBG does not bind NGMN, it appears to be quantitatively the more important NGM metabolite available to target tissues, and probably accounts for a substantial proportion of the progestogenic activity of NGM/EE OCs. However, it is also possible that simultaneous exposure of NGMN and LNG after treatment with NGM/EE may provide clinical benefits not seen with LNG/EE combinations.

Estradiol and norgestimate: a review of their combined use as hormone replacement therapy in postmenopausal women

The focus of this review is hormone replacement therapy (HRT) with continuous administration of micronised, oral 17beta-estradiol 1 mg/day (herein referred to as continuous estradiol) plus micronised, oral norgestimate 90 microg/day administered for 3 days then withdrawn for 3 days in a 6-day repeating sequence (herein referred to as intermittent norgestimate). According to data from randomised, comparative trials of 1 year's duration, continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day relieves climacteric symptoms (vasomotor symptoms and vulvovaginal atrophy) in postmenopausal women. Continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day appeared as effective as estradiol 1 mg/day alone or continuous estradiol 2 mg/day plus continuous norethisterone acetate 1 mg/day in the treatment of postmenopausal women with vasomotor symptoms. Continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day was as effective as continuous estradiol 1 mg/day in causing the maturation of vaginal epithelial cells. In a randomised, double-blind study, bone mineral density (BMD) increased to a significantly greater extent and the rate of bone turnover was slower in postmenopausal women treated with continuous oral estradiol 1 mg/day plus intermittent norgestimate 90 microg/day than in placebo-treated patients. Two randomised, double-blind studies indicated that the addition of norgestimate 90 microg/day to continuous estradiol 1 mg/day did not attenuate the beneficial effects of estradiol on lipid parameters. Continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day was associated with increases in mean serum high density lipoprotein (HDL)-cholesterol levels and decreases in total cholesterol, low density lipoprotein (LDL)-cholesterol and lipoprotein (a) levels, compared with baseline. There was no statistically significant increase in triglyceride levels. In comparative trials, continuous oral estradiol 1 mg/day plus intermittent oral norgestimate 90 microg/day was well tolerated. Headache, breast pain or discomfort, abdominal pain or discomfort, uterine bleeding, dysmenorrhoea, oedema, nausea and depression were the most commonly reported adverse events. Continuous estradiol 1 mg/day plus intermittent oral norgestimate 90 microg/day was associated with a favourable uterine bleeding profile that improved over time. In a randomised trial, 80% of women were free from bleeding (irrespective of spotting) during month 12 of treatment. Norgestimate 90 microg/day was effective in protecting postmenopausal women against induction of endometrial hyperplasia by continuous estradiol 1 mg/day. In conclusion, data from a limited number of randomised studies indicate that HRT with continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day is effective in relieving climacteric symptoms, increasing BMD and slowing the rate of bone turnover in postmenopausal women. This HRT regimen is well tolerated and is associated with a similar incidence of adverse events to that reported in recipients of continuous estradiol 1 mg/day. The norgestimate component of the regimen provides good endometrial protection and is associated with a favourable bleeding profile. Long-term studies investigating the associated risk of breast cancer and thromboembolic events in recipients of continuous estradiol plus intermittent norgestimate are needed. In the meantime, continuous oral estradiol plus intermittent oral norgestimate can be regarded as an effective new option for HRT in postmenopausal women.

Effect of hormone replacement therapy on lipids in perimenopausal and early postmenopausal women

OBJECTIVE

To determine the effects of oral sequential hormone replacement therapy (HRT) on lipid-profile in perimenopausal and early postmenopausal women.

METHODS

We performed a single-center, randomized, placebo-controlled trial. The trial was double blind with respect to 17beta-estradiol/desogestrel (17beta-E-D) and placebo and open with respect to conjugated estrogens/norgestrel (CEE-N). A total of 125 healthy perimenopausal and early postmenopausal women, aged 43-58 years, were recruited from the general population in Zoetermeer, the Netherlands. The intervention consisted of 6 months treatment with 1.5 mg 17beta-estradiol/0.15 mg desogestrel (n=53), 0.625 mg conjugated estrogens/0.15 mg norgestrel (n=36) or placebo (n=36). At baseline, cycle 1, 3 and 6, overnight fasting blood samples were obtained in which lipids were determined. We used linear regression analysis to calculate differences in mean change from baseline in lipids in the active treatment groups compared to placebo.

RESULTS

In both treatment groups significant (P<0.05) falls in low-density-lipoprotein (LDL)-cholesterol (17beta-E-D: -7.8% and CEE-N: -8.4%) and lipoprotein(a) (17beta-E-D: -11.7% and CEE-N: -28.3%) were found compared to placebo. Apolipoprotein A1 (17beta-E-D: 6.8% and CEE-N: 7.3%) and HDL-cholesterol (17beta-E-D: 6.4% and CEE-N: 8.0%) significantly increased compared to placebo. No significant changes were found in the other lipids. Mean changes from baseline in total cholesterol, LDL-cholesterol and apolipoprotein B were significantly more pronounced in postmenopausal women compared to perimenopausal women, adjustment for age-differences did not change the results.

CONCLUSION

Treatment of perimenopausal and early postmenopausal women with 17beta-E-D or CEE-N changes their lipid-profile in a potentially anti-atherogenic direction. Changes appear to be more pronounced in postmenopausal women compared to perimenopausal women.

Long-acting delivery microspheres of levo-norgestrol-poly(3-hydroxybutyrate): their preparation, characterization and contraceptive tests on mice

The preparative technology for sustained release drug delivery microspheres of levo-norgestrol-poly(3-hydroxybutyrate) was optimized based on the in-liquid-drying method. The formation of the drug microspheres was confirmed with differential thermal analysis. The appearance, particle size and distribution, residual CHCl3, drug content, drug release characteristics in vitro, stability and anticonceptive effect on mice of the microspheres were all examined. The average particle size was 64 microm with over 90% of the microspheres being in the range of 28.7-85.8 microm. The residual CHCl3 was lower than 0.001%. The drug release behaviour in vitro could be described by the Higuchi equation and the drug release t1/2 was prolonged by 1.8 times, compared with the original drug LNG. The microspheres were stable for 3 months and showed significant sustained release and anticonceptive effect in mice, and lower toxicity compared with the original drug.

[Liver function tests during administration of triphasic contraceptives containing Norgestimate]

OBJECTIVE

To evaluate serum levels of liver enzymes and bilirubin before and after six cycles of use of a triphasic oral contraceptive containing 35 micrograms of ethinylestradiol and 180/215/250 micrograms of norgestimate (Pramino, Janssen-Cilag).

DESIGN

A prospective, open-label, non-comparative, multicentric phase IV study.

SETTING

Department of Obstetrics and Gynaecology, 1st Medical Faculty, Charles University, Prague.

METHOD

Before the start and after six cycles of Pramino use, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (GMT), and bilirubin were determined in women. As the analyses were performed in different laboratories, the evaluation involved: 1. Subgroups of women examined in laboratories with the same reference range; 2. A group of women examined in laboratories with the upper reference range within the mean +/- SD interval; 3. Percentage variations of the measured values from a concrete upper reference limit.

RESULTS

When evaluating subgroups of women from laboratories with the same standards, significant decreases in AST and bilirubin were seen in some subgroups, a rise in GMT in one subgroup; the other changes were non-significant. When assessing the entire group and percentage variations from standard, a mild rise in GMT was again seen; however, the values remain deep within the normal range. Values above the upper reference limit at the start of the study either do not change significantly throughout the study, or they normalize spontaneously.

CONCLUSION

No clinically significant changes in liver function tests occurred in users of a triphasic oral contraceptive containing norgestimate along with 35 micrograms EE over a period of six cycles of use. The results, as judged by their dynamics, suggest liver function tests are not a useful tool for routine monitoring a healthy combined oral contraceptive user.

[Long-term effects of low-dose combined norethisterone and combined 18-metayl-norethisterone on lipid metabolism in healthy women]

OBJECTIVE

To assess the long-term effects of combined oral contraceptive pills use on the mean of serum TG, TC, HDL-C, LDL-C, ApoA1, ApoB and Lp(a).

METHODS

The study was carried out in 446 women grouped as combined norethisterone containing ethinylestradiol (EE) 35 micrograms and norethisterone 625 micrograms; combined 18-metayl-norethisterone (norgestrel) containing EE 30 micrograms and 18-metayl-norethisterone 300 micrograms for using 5-25 years, and control subjects wearing IUD for the corresponding period. The three groups were similar in age, body mass index (BMI), continued period of contraceptives use and income.

RESULTS

The data showed that changes of varying degree of lipid and lipoprotein parameters were obvious in women of long-term taking low-dose combined norethisterone and norgestrel, compared with the control. The mean of TG, HDL-C, ApoA1 were significantly increased simultaneously (P < 0.05, P < 0.01), indicated multiple effects of two low-dose Chinese COCs on lipid lipoprotein parameters. In addition, A significant increase (P < 0.05) in Lp(a), an independent risk factor for cardiovascular disease, was found in norgestrel group. Further more, the results of stratified analysis to duration of contraceptives use showed that the mean of TC, LDL-C, in the combined norethisterone use less than 15 years, after the adjusting for age, were significantly lower (P < 0.05, P < 0.01) and the ratio of LDL-C/HDL-C was improved (P < 0.05), compared with the Norgestrel; at the same time, the mean of ApoA1 was markedly higher (P < 0.05) in combined norethisterone; the ratio of ApoA1/ApoB (1.87 +/- 0.58) in the combined norethisterone group was superior to the ratio value (1.68 +/- 0.55) in norgestrel group.

CONCLUSIONS

These beneficial effects on lipid metabolism have been considered indicators of potential cardiovascular protective effect of the combined norethisterone for taking pill less than 15 years, but these protective effects would be reduced with adverse change in lipid and lipoprotein parameters for taking combined norethisterone more than 15 years. In contrast, the mean of TC, LDL-C, two known risk factors for cardiovascular system, in the norgestrel use less than 15 years, after the adjusting for age, were significantly increased (P < 0.05, P < 0.01), and adverse changes in the TC/HDL-C ratio (P < 0.05) and ASI value, compared with the combined norethisterone; Lp(a) level was markedly higher in the norgestrel group than that in the control group (P < 0.05). These adverse effects on lipid metabolism have been considered indicators of potential cardiovascular harmful effect of low-dose norgestrel.

100 mg acetylsalicylic acid acutely decreases red cell aggregation in women taking oral contraceptives

Since oral contraceptives (OC) are known to impair blood fluidity and to increase the risk of venous and arterial thrombosis, while acetylsalicylic acid (ASA) decreases the thrombotic risk and modifies some rheologic parameters, we compared the hemorheologic effects of ASA on blood rheology between women treated by OC and women who never received this medication. 25 women under OC were compared to 25 matched women who had never used OC. Blood viscosity (MT90 viscometer) and RBC aggregation (Myrenne aggregometer and AFFIBIO erythroaggregometer) were measured before and 1 hr after women received per os 100 mg ASA, after an overnight fast. The only significant difference between women under OC and controls was an increased RBC aggregation ('M' index +28%, p < 0.04; Affibio aggregation time -21%, p < 0.03). On the whole sample of 50 women as well as in the subgroup of women under OC, ASA decreased RBC partial disaggregation threshold (-1.7%, p < 0.01). These results confirm that RBC aggregation is increased under OC and suggest that 100 mg ASA acutely induces a partial reversal of this RBC hyperaggregation.

Bone density changes during two years treatment with tibolone or conjugated estrogens and norgestrel, compared with untreated controls in postmenopausal women

OBJECTIVE

To quantify and compare the effect of two different hormone replacement therapy regimens on bone mineral density (BMD) and serum alkaline phosphate levels against a group of no treatment control volunteers.

METHODS

An open 104-week comparative study of 113 early postmenopausal women. Fifty volunteered for the no treatment arm; the remainder were randomized to tibolone (T) (n = 32) or conjugated estrogens plus sequential norgestrel (CEEP) (n = 31). BMD was measured at baseline and after 48 and 96 weeks by dual photon absorptiometry.

RESULTS

Baseline BMD was lower in nontherapy controls and with women assigned to CEEP compared with the T group. Statistical significance was not reached. By 96 weeks, increased BMD was observed with both therapies at all sites, whereas controls had lost bone compared with baseline. Changes from baseline with both preparations were significantly different (p < 0.05) from changes in controls for all sites, except femoral neck where the change was significant only with CEEP (p < 0.05). Alkaline phosphatase was significantly reduced in both treatment groups compared with controls (p < 0.05) at 48 and 96 weeks.

CONCLUSIONS

The significant increases in BMD with T and CEEP confirm both regimens are effective in preventing osteoporosis. Without treatment, BMD declines postmenopausally.

17-alpha-ethinylestradiol and norgestrel in combination induce micronucleus increases and aneuploidy in human lymphocyte and fibroblast cultures

Oral contraceptives are highly efficient and easily administered drugs; however, it must not be forgotten that they are composed of chemical substances which can be classified as potential carcinogens. Testing of a substance for genotoxicity represents a reliable approach both to evaluate the genetic hazard and to obtain information on its possible tumorigenic (cancerogenic) properties. The present study was undertaken to evaluate through carefully planned and controlled investigations the in vitro cytogenetic effects of oral contraceptives (ethynilestradiol and norgestrel mixed in the proportion 1:5) using three different concentrations, with two different durations of treatment (48 and 72 h), on two types of human cells (lymphocytes and fibroblasts) and a series of short-term test procedures: sister chromatid exchange (SCE), micronucleus test (MN), and chromosome aberrations (CA). In addition, the FISH procedure and in vitro anaphase and metaphase preparation analyses were performed. In contrast to CA and SCE frequencies, the frequency of MN in treated blood lymphocytes showed higher values by comparison with the controls, although the difference was statistically significant only for the lowest concentration (P = 0. 016). When using pancentromeric alphoid probes, the FISH procedure gave positive signals in more than 85% of micronuclei, clearly indicating that MN may contain whole chromosomes rather than acentric fragments. Unlike the lymphocytes, the fibroblasts showed dose-dependent effects, although those treated with the highest hormone concentrations showed an increased number of highly damaged cells (cytoplasmatic vacuolization, nuclear fragmentation, etc.), a decreased number of anaphase cells, a large number of which were abnormal, and a reduction of mitotic index. In conclusion, our data confirm that hormones do not induce structural chromosome aberrations in lymphocytes and indicate that ethynilestradiol and norgestrel have an aneugenic effect on fibroblast and lymphocyte cultures; FISH analysis on micronuclei from lymphocyte cultures and anaphase preparations from fibroblast cultures support this hypothesis. Teratogenesis Carcinog. Mutagen. 20:147-159, 2000.

Inhibition of skin 5 alpha-reductase by oral contraceptive progestins in vitro

Androgenic disorders of female skin such as hirsutism, acne and alopecia are etiologically caused by androgen excess. Skin 5 alpha-reductase activity is a major factor influencing the manifestation of endogenous androgen excess in women. Oral contraceptives have proven useful for the treatment of androgen disorders of the skin. The mechanisms of action by which oral contraceptives correct skin androgen levels may include inhibition of 5 alpha-reductase and androgen receptor activity. We investigated the inhibitory effect of oral contraceptive progestins and ethinyl estradiol on skin 5 alpha-reductase and their influence on androgen receptor activity and affinity, using three different in vitro assay systems. It was shown that norgestimate blocked 5 alpha-reductase activity with an IC50 value of 10 microM, followed by levonorgestrel (IC50 52 microM), dienogest (IC50 55 microM), cyproterone acetate (IC50 87 microM) and gestodene (IC50 98 microM). To determine the full androgenic potential of the progestins, androgen receptor binding affinities and activation potentials were determined. The progestins norgestimate and dienogest in particular combined 5 alpha-reductase inhibition with minimal androgenic potential. These data demonstrate that the progestins norgestimate and dienogest might help in the treatment of clinical hyperandrogeny in women.

Impact of subdermal norgestrel on hepatic acyl-coenzyme A:cholesterol- acyltransferase (ACAT) activity: possible antiatherogenic effect

The impact of subdermally placed ethinyl estradiol, norgestrel, and the combination of the two on cholesterol metabolism as measured by hepatic acyl:cholesterol-acyltransferase (ACAT) activity was examined in the rat model. A total of 48 rats were assigned to one of 6 groups, receiving either 0.1 mg or 1.0 mg of ethinyl estradiol daily, 1.0 or 10 mg of norgestrel daily, and combinations of either 0.1 mg ethinyl estradiol/1.0 mg norgestrel or 1.0 mg ethinyl estradiol/10 mg norgestrel daily. All drugs were administered through subdermally placed time release capsules. The administration of norgestrel only in either 1.0 mg or 10 mg resulted in significantly lower rates of ACAT activity (0.77 +/- 0.566 and 0.91 +/- 0.239 pmol/mg/min, respectively). The combination of 1.0 ethinyl estradiol and 10 mg norgestrel resulted in a significant increase in ACAT activity to 2.17 +/- 0.873. This combination also resulted in significantly greater weight loss at the conclusion of treatment [247.83 +/- 6.2 g (pre) vs. 205.50 +/- 10.6 (post)]. There were no other differences in ACAT activity between groups and no other differences in weight, both between groups and pre- and post-treatment within groups. In summary, subdermally placed norgestrel resulted in a significant lowering of ACAT activity not seen with either administration of ethinyl estradiol alone or the combination of ethinyl estradiol and norgestrel in doses ranging from 0.1 to 1.0 mg of ethinyl estradiol and 1.0 to 10.0 mg of norgestrel. Significantly increased ACAT activity for the combination of 1.0 ethinyl estradiol and 10 mg norgestrel over either ethinyl estradiol or norgestrel alone or a lower dose combination suggests a dose-related threshold and drug-drug interaction for this effect. These results suggest that subdermally placed norgestrel may result in significantly lower ACAT activity and may have a potential role as an antiatherogenic treatment.