Use of metformin for prevention of ovarian hyperstimulation syndrome: a novel approach

Repurposing new drug candidates and identifying crucial molecules underlying PCOS Pathogenesis Based On Bioinformatics Analysis

BACKGROUNDS

Polycystic ovary syndrome affects 7% of women of reproductive ages. Poor-quality oocytes, along with lower cleavage and implantation rates, reduce fertilization.

OBJECTIVE

This study aimed to determine crucial molecular mechanisms behind PCOS pathogenesis and repurpose new drug candidates interacting with them. To predict a more in-depth insight, we applied a novel bioinformatics approach to analyze interactions between the drug-related and PCOS proteins in PCOS patients.

METHODS

The newest proteomics data was retrieved from 16 proteomics datasets and was used to construct the PCOS PPI network using Cytoscape. The topological network analysis determined hubs and bottlenecks. The MCODE Plugin was used to identify highly connected regions, and the associations between PCOS clusters and drug-related proteins were evaluated using the Chi-squared/Fisher's exact test. The crucial PPI hub-bottlenecks and the shared molecules (between the PCOS clusters and drug-related proteins) were then investigated for their drug-protein interactions with previously US FDA-approved drugs to predict new drug candidates.

RESULTS

The PI3K/AKT pathway was significantly related to one PCOS subnetwork and most drugs (metformin, letrozole, pioglitazone, and spironolactone); moreover, VEGF, EGF, TGFB1, AGT, AMBP, and RBP4 were identified as the shared proteins between the PCOS subnetwork and the drugs. The shared top biochemical pathways between another PCOS subnetwork and rosiglitazone included metabolic pathways, carbon metabolism, and citrate cycle, while the shared proteins included HSPB1, HSPD1, ACO2, TALDO1, VDAC1, and MDH2. We proposed some new candidate medicines for further PCOS treatment investigations, such as copper and zinc compounds, reteplase, alteplase, gliclazide, Etc.

CONCLUSION

Some of the crucial molecules suggested by our model have already been experimentally reported as critical molecules in PCOS pathogenesis. Moreover, some repurposed medications have already shown beneficial effects on infertility treatment. These previous experimental reports confirm our suggestion for investigating our other repurposed drugs (in vitro and in vivo).

New clinical targets of d-chiro-inositol: rationale and potential applications

INTRODUCTION

Inositols have a key role in ovarian physiology and the literature reports a wealth of studies about the major isomer, myo-inositol (MI). However, information about d-chiro-inositol (DCI) is still scarce, despite the ratio MI:DCI is tissue-specific and actively maintained by an insulin-dependent epimerase enzyme.

AREAS COVERED

This expert opinion provides an overview of the physiological contribution of DCI in regulating steroidogenesis. DCI indeed mediates the intracellular signaling of insulin, which induces the biosynthesis of androgens. Studies on second messengers of insulin also revealed that DCI has a specific role in modulating the activity of aromatase enzyme. Specifically, recent findings demonstrated that DCI influences the enzyme gene expression, thus reducing the conversion of androgens into estrogens.

EXPERT OPINION

Available evidence suggests that the effects of DCI administration may be similar to those of aromatase inhibitors, but without causing hypo-estrogenic states. Therefore, DCI treatments should be evaluated for either estrogen-dependent gynecological conditions or low testosterone states in male subjects.

Ovarian angiogenesis in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most prevalent endocrine pathology among women in reproductive age. Its main symptoms are oligo or amenorrhea, hyperandrogenism and the presence of ovarian cysts. It is also associated with infertility, obesity and insulin resistance. Mainly due to its heterogeneity, PCOS treatments are directed to manage its symptoms and to prevent associated diseases. The correct formation and regression of blood vessels during each ovarian cycle is indispensable for proper follicular development, ovulation and corpus luteum formation. The importance of these processes opened a new and promising field: ovarian angiogenesis. Vascular alterations characterize numerous pathologies, either with increased, decreased or abnormal angiogenesis. In the last years, several anomalies of ovarian angiogenesis have been described in women with PCOS. Therefore, it has been suggested that these alterations may be associated with the decreased - or lack of - ovulation rates and for the formation of cysts in the PCOS ovaries. Restoration of a proper vessel formation in the ovaries may lead to improved follicular development and ovulation in these patients. In the present review, we attempt to summarize the alterations in ovarian angiogenesis that have been described in women with PCOS. We also discuss the therapeutic approaches aimed to correct these alterations and their beneficial effects on the treatment of infertility in PCOS.

Myo-inositol is a promising treatment for the prevention of ovarian hyperstimulation syndrome (OHSS): an animal study

PURPOSE

To evaluate the efficacy of myo-inositol (MI) pretreatment in OHSS.

METHODS

In this experimental OHSS rat model, 42 immature Wistar albino female rats were divided into 6 groups: (1) the control group, (2) the ovarian stimulation group, (3) the OHSS group, (4) the OHSS + Metformin group, (5) OHSS + MI group, (6) OHSS + Metformin + MI group. OHSS was established after treatment with metformin and myo-inositol for 14 days, in the meanwhile the treatment of metformin and myo-inositol was also continued. All animals were killed 48 h after hCG administration and were compared in terms of vascular permeability, ovarian weight and diameter, ovarian VEGF, COX-2 and PEDF expression (immunohistochemistry), serum PEDF and estradiol (E2) levels.

RESULTS

Vascular permeability, VEGF and COX-2 expressions were reduced in animals treated with MI and/or metformin. While PEDF expression was increased in the groups taking metformin, there was no difference in PEDF expression in the group taking MI and OHSS group. There was no significant difference in serum PEDF levels between groups. Blood E2 levels were decreased in groups treated with MI or metformin compared to the OHSS group.

CONCLUSIONS

Our data demonstrate that myo-inositol is effective in preventing OHSS, similar to metformin. Although the two drugs are thought to act through distinct mechanisms, there is no apparent benefit to co-treatment with both drugs in an animal model of OHSS. Administration of myo-inositol prior to IVF treatment may favor the control of ovulation induction. Further studies are necessary to elucidate the mechanism of action and further support our findings.

Can dopamine agonist at a low dose reduce ovarian hyperstimulation syndrome in women at risk undergoing ICSI treatment cycles? A randomized controlled study

OBJECTIVE

Dopamine agonists were proposed as a preventive strategy for severe ovarian. The aim of this randomized controlled study is to evaluate the role of dopamine agonist at lower doses (0.25mg) as a preventive strategy of severe hyperstimulation syndrome (OHSS) in women at high risk in IVF/ICSI treatment cycles.

STUDY DESIGN

Two hundred women at risk to develop OHSS undergoing IVF/ICSI treatment cycle were included; the study group received 0.25mg of cabergoline for 8 days from the day of HCG administration versus no treatment for the prevention of OHSS. Reduction of the incidence OHSS was the primary outcome.

RESULTS

The overall incidence of OHSS was significantly reduced, almost 50%, in cabergoline group in comparison with control group (RR: 0.5, 95% CI: 0.29-0.83), with absolute risk reduction following cabergoline administration 11% (ARR: 0.11, 95% CI: 1.09-20.91). The corresponding number needed to treat (NNT) was 9.

CONCLUSION

Prophylactic treatment with the dopamine agonist, cabergoline, at lower doses (0.25mg) reduces the incidence of OHSS in women at high risk undergoing IVF/ICSI treatment.

VEGF antagonist for the prevention of ovarian hyperstimulation syndrome: Current status

Ovarian Hyperstimulation Syndrome (OHSS) an iatrogenic and potentially life-threatening complication resulting from an exaggerated response to ovulation induction with gonadotropins during assisted reproductive technologies, is a self-limiting disorder with a broad spectrum of clinical manifestations related to increased capillary permeability and fluid retention brought about by many biochemical mediators especially vascular endothelium growth factor (VEGF), playing a pivotal role in its pathophysiology. Although various strategies had been proposed and tried to prevent this serious complication none was found to be completely effective. With the current knowledge and understanding of the causative molecule i.e. VEGF in the pathogenesis of OHSS, pharmacologic tools targeting this member of the family of heparin binding proteins, seems promising. Antagonizing and blocking VEGF action by dopamine agonists especially Cabergoline has shown to be a valid alternative to overcome the changes induced by the gonadotropins. Delaying embryo transfer with embryo cryopreservation definitely reduces the incidence of OHSS but not the early OHSS. In-vitro maturation of oocytes a major breakthrough in the field of ART although totally eliminates the risk of OHSS is highly labor intensive and cannot routinely carried in all cycles. Thus the newer drugs, mainly the dopamine agonists in the light of the new pathogenic and pharmacological evidence, should definitely be considered for prevention of both early and late OHSS.

Metformin in the treatment of clomiphene citrate-resistant women with polycystic ovary syndrome undergoing in vitro fertilisation treatment: a randomised controlled trial

This study was conducted to determine the efficacy of metformin vs placebo in women with polycystic ovary syndrome (PCOS) undergoing IVF treatment. A total of 66 CC-resistant patients were studied prospectively. The women were randomly assigned to receive 850 mg of metformin (n = 34) or placebo (n = 32) twice daily that started 1 month before commencing the IVF treatment and continued to the day of the pregnancy test. Compared with the metformin-treated group, women who received a placebo had a significant increase in terms of days of stimulation with HMG, number of HMG ampoules, number of follicles >14 mm, number of oocytes retrieved, number of mature eggs, fertilisation rate and oestradiol level on the day of hCG administration. Similarly, women in the placebo group showed a significant increase in poor quality embryos, cancellation rate and the rate of ovarian hyperstimulation syndrome, as compared with the metformin-treated group. On the other hand, women who received metformin showed a significantly higher number of good quality embryos and implantation rate when compared with the placebo controls. Despite the transfer of a similar number of embryos, an insignificant increased in the pregnancy rate along with significant reduction in the abortion rate was observed in the metformin-treated group as compared with the placebo controls. No fetal abnormalities were encountered in the babies born in the metformin-treated group. It is concluded that metformin affects positively the quality of both oocytes and embryos without a significant increase in the pregnancy rate. It decreases significantly the rates of abortion and ovarian hyperstimulation syndrome.

Cabergoline reduces the early onset of ovarian hyperstimulation syndrome: a prospective randomized study

Prophylactic use of cabergoline has been associated with a decrease in the severity of ovarian hyperstimulation syndrome (OHSS). A prospective randomized study was designed to evaluate the potential of cabergoline to decrease the incidence of OHSS in high-risk patients undergoing assisted reproductive technology treatment; 166 patients with oestradiol concentrations over 4000 pg/ml on the day of human chorionic gonadotrophin (HCG) administration were evaluated. They all received 20 g routine preventive intravenous human albumin on the day of oocyte retrieval. They were then randomized into two groups: group A (n = 83) received 0.5 mg oral cabergoline per day for 3 weeks beginning on the day after oocyte retrieval, and group B (n = 83) received no medication. 'Early' OHSS was defined as being when the onset of the syndrome was initiated during the first 9 days after HCG administration, and 'late' OHSS was defined as being when the onset of the syndrome was initiated from 10 days after HCG administration. In group A, no patients progressed to 'early' OHSS and nine patients (10.8%) developed 'late' OHSS; in group B, 12 patients (15.0%) progressed to 'early' OHSS and three (3.8%) to 'late' OHSS. Although the risk of 'early' OHSS decreased significantly (P < 0.001), the risk of 'late' onset OHSS did not. The two groups presented no changes in pregnancy, implantation or miscarriages rates.

Hydrothorax as the sole manifestation of ovarian hyperstimulation syndrome: unusual case and literature review

An unusual case of a unilateral massive hydrothorax after IVF treatment is reported in a 41-year-old patient, which developed as the only manifestation of ovarian hyperstimulation syndrome. The literature on such rare presentation is also reviewed to highlight its diagnostic features and prognosis.

IVF, IVM, natural cycle IVF, minimal stimulation IVF – time for a rethink

Considerable changes are afoot in the practice of assisted human conception. Doubts about its methods, especially over endocrinology, concern its complexity and its expense. IVF has spread worldwide since its beginnings in the UK, but its current practice, termed routine IVF, is being challenged by simpler routines. These include natural cycle IVF, which has been in the background for many years, minimal stimulation IVF, where doses of hormones are reduced, and the in-vitro maturation of human oocytes ready for fertilization in vitro (IVM). These three approaches are now practised in increasing numbers of IVF clinics, and may well replace routine IVF. The events leading to current interest in these methods will be discussed briefly in this review.