Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0021359 (
infertility
)
26,075
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Polycystic ovary syndrome (PCOS) is the major cause of anovulatory
infertility
. Throughout the years, several and effective medical and surgical therapies have been proposed to treat the ovarian dysfunction. To date, new effective and cheap drugs, such as metformin and
aromatase
inhibitors, are available. The aim of the present descriptive review is to describe the main therapeutic approaches for treating infertile patients with PCOS.
...
PMID:Ovulation induction in infertile patients with polycystic ovary syndrome. 1658 68
Endometriosis is an estrogen-dependent gynaecological disease associated with pain and
infertility
, which occurs in humans and menstruating primates. In this study, the marmoset monkey (Callithrix jacchus), which is a non-menstruating primate with high circulating estrogen levels, was used to test firstly the hypothesis that endometriosis is based on uterine shedding into the peritoneal cavity, secondly to study the pathogenesis of endometriosis due to its estrogenic situation. Female marmoset monkeys (n = 29) were exposed to two different experimental procedures (non-invasive versus invasive) for intrapelvic placement of endometrial cells by uterine flushing over an experimental period of 2-3 years. First endometriotic foci were detected by colour Doppler ultrasound at the bladder, the uterus and the ovaries at the earliest after 4 months of either treatments. However, invasive induction was more effective in terms of the time-course of induction and the number of resulting endometriotic foci. The analysis of the endometriotic foci by histology, immunohistochemistry and molecular techniques allowed a division into two distinct groups: an initial developing stage occurred, which under further treatment led to the second stage of established endometriosis. Both procedures showed a treatment-dependent increase of vascular supply to the endometriotic foci over the experimental period. The invasive method induced the final established stage of endometriosis more rapidly, with the expression of steroid receptors,
aromatase
, 17betaHSD1 and CD10. Altogether, 72% of the treated marmoset monkeys developed endometriosis under our endometrial reflux protocols. Our data support the theory that endometriosis can be induced artificially in a non-menstruating primate (C. jacchus) by endometrial shedding into the peritoneal cavity. Because the marmoset is a primate with very high peripheral estrogen levels, this offers an interesting model for studying the pathogenesis of this estrogen-dependent disease, as well as for therapeutic impacts on enzymes involved in steroid metabolism.
...
PMID:Induction of endometriosis in the marmoset monkey (Callithrix jacchus). 1660 6
Treatment of normogonadotropic anovulatory
infertility
(World Health Organization class 2, or WHO2) is by induction of ovulation using clomiphene citrate (CC), followed by follicle-stimulating hormone (FSH) in cases of treatment failure. Not all patients will become ovulatory or will conceive with this treatment. Others, exhibiting multifollicular instead of monofollicular development, may encounter complications such as ovarian hyperstimulation and multiple pregnancy. Recently introduced alternative treatment interventions-such as insulin-sensitizing drugs,
aromatase
inhibitors, or laparoscopic electrocautery of the ovaries-may offer the possibility of improving the efficacy of the classical ovulation induction algorithm. Based on initial patient characteristics, it may be possible to identify specific patient subgroups with altered chances of success or complications while using one of these interventions. Regarding CC and FSH ovulation induction, this has been performed using multivariate prediction models. This approach may enable us to improve safety, cost-effectiveness, and patient convenience in future ovulation induction.
...
PMID:Ovulation induction in normogonadotropic anovulation (PCOS). 1677 56
Polycystic ovary syndrome is a multi-system endocrinopathy with long-term metabolic and cardiovascular health consequences. Patients typically present due to symptoms of irregular menstruation, hair growth, or
infertility
; however, recent management options are aimed at further treating underlying glucose-insulin abnormalities as well as androgen excess for proactive control of symptoms. By a 2003 international consensus conference, diagnosis is made by two out of three criteria: chronic oligoovulation or anovulation after excluding secondary causes, clinical or biochemical evidence of hyperandrogenism (but not necessarily hirsutism due to inter-patient variability in hair follicle sensitivity), and radiological evidence of polycystic ovaries. Traditional medical treatment options include oral contraceptive pills, cyclic progestins, ovulation induction, and anti-androgenic medications (aldosterone antagonist, 5alpha-reductase antagonist, and follicle ornithine decarboxylase inhibitor). Recent pharmacotherapies include insulin-sensitizing medications metformin and two thiazolidinediones (rosiglitazone/Avandia and pioglitazone/Actos), a CYP19
aromatase
inhibitor (letrozole/Femara), and statins to potentially lower testosterone levels.
...
PMID:Contemporary medical therapy for polycystic ovary syndrome. 1701 Sep 75
The aim of the present study was to measure the in vitro
aromatase
activity in granulosa cells of women with endometriosis submitted to assisted reproduction techniques. A case-control study was conducted on eight patients with endometriosis and eight with other
infertility
causes submitted to in vitro fertilization or intracytoplasmic sperm injection. Granulosa cells were obtained from pre-ovulatory follicles during oocyte retrieval and cultured for 24 h in the presence or absence of testosterone (2 x 10(-6) and 2 x 10(-5) M), follicle-stimulating hormone (FSH) and insulin-like growth factor-I (IGF-I) (both at 50 ng/ml). Estradiol (radioimmunoassay) was measured in the obtained culture fluids. The basal production of estradiol and its production under testosterone addition to the culture (
aromatase
activity) were analyzed. Reduced
aromatase
activity was detected in cultured granulosa cells in endometriosis cases, compared with controls, when testosterone was added at the concentration at 2 x 10(-6) M (p = 0.0303). The basal production of estradiol was also reduced in endometriosis patients (p = 0.0390). The effect of addition of FSH and IGF-I did not differ between groups. In conclusion, the in vitro basal production of estradiol and
aromatase
activity in granulosa cells were reduced in women with endometriosis submitted to assisted reproduction techniques, compared with the control group.
...
PMID:Reduced aromatase activity in granulosa cells of women with endometriosis undergoing assisted reproduction techniques. 1701 4
For almost half a century, the first-line treatment for ovulation induction in cases of anovulation, unexplained
infertility
, or mild male factor has been clomifene (clomiphene citrate). Clomifene is an effective and safely used oral agent, but is known to have relatively common antiestrogenic endometrial and cervical mucous adverse effects that could prevent pregnancy in the face of successful ovulation. In addition, there is a significant risk of multiple pregnancies with clomifene compared with natural cycles. These drawbacks are mainly a result of the extended antiestrogenic effect of clomifene as a result of its accumulation in the body (clomifene isomers have a half-life of several days up to few weeks). Because of these problems, we proposed the concept of
aromatase
inhibition as a new method of ovulation induction that could avoid many of the adverse effects of clomifene. Over the last few years several published studies, both controlled and noncontrolled, compared clomifene and treatment with
aromatase
inhibitors (AIs), either alone or in combination with gonadotropins, for ovulation induction or augmentation. These studies found AIs as effective as clomifene in inducing ovulation, with the major advantage of absence of any antiestrogenic adverse effects. Several other major advantages of AIs include the lower serum estrogen production per developing follicle resulting in more physiological estrogen levels around the time of ovulation and good pregnancy rates with a lower incidence of multiple pregnancy than with clomifene. When combined with gonadotropins for assisted reproductive technologies, AIs reduce the dose of gonadotropins required for optimal follicle recruitment and improve the response to gonadotropin stimulation in poor responders. Such preliminary evidence suggests that AIs may replace clomifene in the future because of similar efficacy with a reduced adverse-effect profile. However, we believe that definitive studies in the form of randomised controlled trials comparing clomifene with AIs are needed.
...
PMID:Potential of aromatase inhibitors for ovulation and superovulation induction in infertile women. 1713
Ovulation induction is the principal
infertility
treatment for women with polycystic ovarian syndrome (PCOS). Among PCOS patients who are overweight or obese, weight loss is the most physiologic method of inducing ovulation. For women in whom weight loss is not possible, or for lean women with PCOS, clomiphene citrate is an effective first-line method of ovulation induction. In clomiphene-resistant women, alternative treatments include adjunctive metformin or dexamethasone,
aromatase
inhibitors, or ovarian drilling. If there is no pregnancy despite several cycles of successful ovulation induction, gonadotropin treatment should be considered, in which case in vitro fertilization is recommended as the safest and most effective strategy.
...
PMID:Ovulation induction management of PCOS. 1730 40
The
aromatase
inhibitor letrozole is a novel agent that can be used as an alternative to clomiphene citrate for ovulation induction in patients with unexplained
infertility
. The dose of letrozole used has varied between studies, and this study aimed to compare the three most commonly used doses: 2.5, 5 and 7.5 mg. A total of 179 patients were randomly recruited in this prospective study with 58, 61 and 60 patients in each dosage group respectively. This study reports a significantly higher (P < 0.05) number of follicles (total, > 14 mm and > or = 18 mm) on the day of administration of human chorionic gonadotrophin in the 7.5 mg group, associated with significantly fewer (P < 0.05) days of stimulation. However the pregnancy and miscarriage rates were similar in the three groups. In conclusion, it seems that the use of higher doses of letrozole offers no advantage in terms of pregnancy rates over the lower (2.5 mg) dose.
...
PMID:Randomized controlled trial of three doses of letrozole for ovulation induction in patients with unexplained infertility. 1750 94
The selective estrogen receptor modulator, clomiphene citrate (CC), has been the principal drug used for induction of ovulation in women with polycystic ovarian syndrome (PCOS). CC is associated with adverse side effects and low pregnancy rates attributed to long-lasting estrogen receptor depletion. Anastrozole and letrozole are potent, non-steroidal, reversible
aromatase
inhibitors, developed for postmenopausal breast cancer therapy. We hypothesized that
aromatase
inhibitors could mimic the action of CC in reducing estrogen negative feedback on follicle stimulating hormone (FSH) secretion, without depleting estrogen receptors. In a series of preliminary studies, we reported the success of
aromatase
inhibition in inducing ovulation in anovulatory women with PCOS. Moreover, we showed that concomitant use of
aromatase
inhibitors resulted in a significant reduction of the FSH dose needed for controlled ovarian hyperstimulation. We suggest that
aromatase
inhibitors act through an increase in endogenous gonadotropin secretion as well as through increased intraovarian androgen levels that may increase ovarian FSH receptors. Recently, we demonstrated the safety of
aromatase
inhibitors in pregnancy outcome studies examining spontaneous pregnancy loss, multiple pregnancy rates and congenital anomalies compared to a control group of
infertility
patients treated with CC.
...
PMID:Aromatase inhibitors in ovarian stimulation. 1760 15
Polycystic Ovary Syndrome (PCOS) is an endocrine-metabolic pathology related with
infertility
and recurrent miscarriage. We have previously shown that the endometrium of these patients can exhibit a potentially higher sensitivity to estrogen action, being estrogens important regulators of the cell cycle and tissue homeostasis. The effect of estrogens on tissues depends on their in situ availability, which is in part regulated by the activity of steroid metabolic enzymes within the tissues. Therefore, the objective of the present study was to analyze if the activity and/or expression of steroid metabolic enzymes in endometria from women with PCOS differ from controls. For this purpose, the activity of the enzymes was determined by using radiometric assays and the mRNA levels measured by semi-quantitative RT-PCR. Both assays were assessed in endometria obtained during mid secretory phase from control (CE, n=12) and PCOS women (PCOSE, n=11). For the statistical analyses, Mann-Whitney and Student's t-tests were used to compare CE and PCOSE, considering a p value <0.05 significantly different. The results showed an increase in the sulfatase activity in PCOS respect to control endometria (200+/-28pmol/mg vs. 115+/-13pmol/mgproth; p<0.05), in agreement with the higher mRNA levels found for the enzyme in PCOSE. In addition, a PCOSE exhibited lower activity of sulfotransferase respect to the control group (50+/-21pmol/mg vs. 124+/-10pmol/mgproth; p<0.05), whereas a higher level of 17beta-hydroxysteroid dehydrogenase type 1mRNA was found in PCOSE compared with the control tissues (p<0.05). The activity of 17beta-hydroxysteroid dehydrogenase type 2 and the mRNA levels of sulfotransferase were similar in both groups; meanwhile, the expression of
aromatase
was undetectable. These data indicate that the sulfatase pathway could play an important role in the local production of estrogens in PCOSE from secretory phase. This potentially higher bioavailability of estrogens in endometria from PCOS women could influence the deregulation of tissue homeostasis that we have previously reported, and could partially explain the poor reproductive performance observed in this group of patients.
...
PMID:Activities of steroid metabolic enzymes in secretory endometria from untreated women with Polycystic Ovary Syndrome. 1795 76
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>