Melatonin: shedding light on infertility?--A review of the recent literature

Chronic Caffeine Consumption, Alone or Combined with Agomelatine or Quetiapine, Reduces the Maximum EEG Peak, As Linked to Cortical Neurodegeneration, Ovarian Estrogen Receptor Alpha, and Melatonin Receptor 2

RATIONALE

Evidence of the effects of chronic caffeine (CAFF)-containing beverages, alone or in combination with agomelatine (AGO) or quetiapine (QUET), on electroencephalography (EEG), which is relevant to cognition, epileptogenesis, and ovarian function, remains lacking. Estrogenic, adenosinergic, and melatonergic signaling is possibly linked to the dynamics of these substances.

OBJECTIVES

The brain and ovarian effects of CAFF were compared with those of AGO + CAFF and QUET + CAFF. The implications of estrogenic, adenosinergic, and melatonergic signaling and the brain-ovarian crosstalk were investigated.

METHODS

Adult female rats were administered AGO (10 mg/kg), QUET (10 mg/kg), CAFF, AGO + CAFF, or QUET + CAFF, once daily for 8 weeks. EEG, estrous cycle progression, and microstructure of the brain and ovaries were examined. Brain and ovarian 17β-estradiol (E2), antimullerian hormone (AMH), estrogen receptor alpha (E2Rα), adenosine receptor 2A (A2AR), and melatonin receptor 2 (MT2R) were assessed.

RESULTS

CAFF, alone or combined with AGO or QUET, reduced the maximum EEG peak, which was positively linked to ovarian E2Rα, negatively correlated to cortical neurodegeneration and ovarian MT2R, and associated with cystic ovaries. A large corpus luteum emerged with AGO + CAFF and QUET + CAFF, antagonizing the CAFF-mediated increased ovarian A2AR and reduced cortical E2Rα. AGO + CAFF provoked TTP delay and increased ovarian AMH, while QUET + CAFF slowed source EEG frequency to δ range and increased brain E2.

CONCLUSIONS

CAFF treatment triggered brain and ovarian derangements partially antagonized with concurrent AGO or QUET administration but with no overt affection of estrus cycle progression. Estrogenic, adenosinergic, and melatonergic signaling and brain-ovarian crosstalk may explain these effects.

Treatment With a Patented 3.6:1 Myo-Inositol to D-chiro-Inositol Ratio, Antioxidants, Vitamins and Minerals Food Supplement in Women With a History of Assisted Reproductive Technique (ART) Failures: A Series of Case Reports

Infertility affects 15% of couples in reproductive age worldwide. In women in particular, infertility can be caused by various abnormalities, with polycystic ovary syndrome (PCOS) being the most common. Currently, there are many assisted reproductive techniques (ART) available to combat the burden of infertility. However, positive results are not guaranteed. The administration of inositol has been shown to increase positive reproductive outcomes in women undergoing ART. Here we present a series of clinical cases in which women with a history of infertility and previously failed ART, supplemented with a specific 3.6:1 MYO:DCI ratio, antioxidants, vitamins, and minerals for a period of 1 to 3 months before undergoing in vitro fertilization (IVF). In this series of case reports, we provide preliminary evidence that supplementation with a specific 3.6:1 MYO to DCI ratio, as well as antioxidants, vitamins, and minerals may contribute positively to female fertility in women undergoing IVF, with a history of primary or secondary infertility and previously failed ART.

A phase 1 study of dimdazenil to evaluate the pharmacokinetics, food effect and safety in Chinese healthy subjects

Background and objective: As a partial positive allosteric modulator of the gamma-aminobutyric acid A (GABAA) receptor, dimdazenil was used for the treatment of insomnia with the potential to alleviate associated side effects compared to full agonists. The objective of this trial is to assess the safety, tolerability, food effect and pharmacokinetics following single and multiple doses of dimdazenil in Chinese healthy subjects. Methods: In this phase 1 trial, 36 healthy subjects aged ≥18 years were assigned to receive a single dose of 1.5, 2.5, or 5 mg dimdazenil, with each dose cohort consisting of 12 subjects, and 14 subjects were assigned to receive a multiple 2.5 mg daily dose of dimdazenil for 5 days. Safety, tolerability, and pharmacokinetic characteristics were evaluated. Results: Of the 50 subjects enrolled and 49 completed the trial, the incidences of treatment-emergent adverse events (AEs) in the single-dose groups of 1.5, 2.5, and 5 mg were 16.7%, 58.3% and 66.7% respectively, while 61.5% in the multiple-dose group. There were no serious AEs, deaths, AEs leading to discontinuation or AEs of requiring clinical intervention in any treatment groups. The most treatment-emergent AEs were dizziness (n = 4, 8.2%), hyperuricemia (n = 2, 6.1%), upper respiratory tract infection (n = 2, 6.1%), diastolic blood pressure decreased (n = 2, 6.1%), blood TG increased (n = 2, 6.1%) and RBC urine positive (n = 2, 6.1%). All AEs were mild-to-moderate and transient, and no severe AEs were documented in any study phase. The PK profile of dimdazenil and its active metabolite Ro46-1927 was linear across 1.5-5 mg oral doses in humans. The median Tmax for dimdazenil was in the range of 0.5-1.5 h, and the apparent terminal t1/2z ranged from 3.50 to 4.32 h. Taking Dimdazenil with food may delay Tmax and decrease Cmax, without affecting the total exposure (AUC). No relevant accumulations of dimdazenil and Ro 46-1927 were observed in multiple-dose group. Conclusion: Dimdazenil was generally well tolerated in healthy Chinese subjects after single and 5 days-multiple dosing. The pharmacokinetic properties of dimdazenil are compatible with a drug for the treatment of insomnia. Clinical Trial Registration: chinadrugtrials.org.cn, identifier CTR20201978.

Are ICSI results affected by months and seasons? A retrospective cohort study of fresh and frozen cycles

In present study, we aimed to investigate the effect of seasonal variation on ICSI results both in fresh and frozen embryo transfer cycles. Between January 2007 and December 2019, a total of 4039 ICSI cycles (3227 fresh and 812 frozen ET) which resulted in embryo transfer were included in the study. We found no significant difference in the pregnancy outcome among different seasons and months. The best results were obtained for spring (41.0%) and the least for winter (37.1%) in fresh cycles and the best for spring (42.5%) and the least for winter (29.7%) in FET cycles. In monthly distribution, the best results were obtained for September (57.0%) and the least for November (24.1%) in fresh cycles and the best for October (49.3%) and the least for December (20.2%) in FET cycles. Our study did not show any significant influence of the months or seasons on clinical pregnancy rates in either fresh and frozen embryo transfers. However, the difference among months in frozen cycles was notable although it did not reach statistical significance. It can be suggested that the strict control of reproductive hormones especially in fresh cycles as well as the standardized laboratory temperature minimize the influence of seasonal effect on ICSI outcome.

Aging-Related Ovarian Failure and Infertility: Melatonin to the Rescue

Aging has a major detrimental effect on the optimal function of the ovary with changes in this organ preceding the age-related deterioration in other tissues, with the middle-aged shutdown leading to infertility. Reduced fertility and consequent inability to conceive by women in present-day societies who choose to have children later in life leads to increased frustration. Melatonin is known to have anti-aging properties related to its antioxidant and anti-inflammatory actions. Its higher follicular fluid levels relative to blood concentrations and its likely synthesis in the oocyte, granulosa, and luteal cells suggest that it is optimally positioned to interfere with age-associated deterioration of the ovary. Additionally, the end of the female reproductive span coincides with a significant reduction in endogenous melatonin levels. Thus, the aims are to review the literature indicating melatonin production in mitochondria of oocytes, granulosa cells, and luteal cells, identify the multiple processes underlying changes in the ovary, especially late in the cessation of the reproductive life span, summarize the physiological and molecular actions of melatonin in the maintenance of normal ovaries and in the aging ovaries, and integrate the acquired information into an explanation for considering melatonin in the treatment of age-related infertility. Use of supplemental melatonin may help preserve fertility later in life and alleviate frustration in women delaying childbearing age, reduce the necessity of in vitro fertilization–embryo transfer (IVF-ET) procedures, and help solve the progressively increasing problem of non-aging-related infertility in women throughout their reproductive life span. While additional research is needed to fully understand the effects of melatonin supplementation on potentially enhancing fertility, studies published to date suggest it may be a promising option for those struggling with infertility.

Insomnia

Insomnia is highly prevalent in clinical practice, occurring in up to 50% of primary care patients. Insomnia can present independently or alongside other medical conditions or mental health disorders and is a risk factor for the development and exacerbation of these other disorders if not treated. In 2016, the American College of Physicians recommended that insomnia be specifically targeted for treatment. The recommended first-line treatment for insomnia, whether the underlying cause has been identified or not, is cognitive behavioural therapy for insomnia (CBT-I). Currently, there is no global consensus regarding which pharmacological treatment has the best efficacy or risk-benefit ratio. Both CBT-I and pharmacological intervention are thought to have similar acute effects, but only CBT-I has shown durable long-term effects after treatment discontinuation. Administering a combined treatment of CBT-I and medication could decrease the latency to treatment response, but might diminish the durability of the positive treatment effects of CBT-I.

Is Melatonin the “Next Vitamin D”?: A Review of Emerging Science, Clinical Uses, Safety, and Dietary Supplements

Melatonin has become a popular dietary supplement, most known as a chronobiotic, and for establishing healthy sleep. Research over the last decade into cancer, Alzheimer’s disease, multiple sclerosis, fertility, PCOS, and many other conditions, combined with the COVID-19 pandemic, has led to greater awareness of melatonin because of its ability to act as a potent antioxidant, immune-active agent, and mitochondrial regulator. There are distinct similarities between melatonin and vitamin D in the depth and breadth of their impact on health. Both act as hormones, affect multiple systems through their immune-modulating, anti-inflammatory functions, are found in the skin, and are responsive to sunlight and darkness. In fact, there may be similarities between the widespread concern about vitamin D deficiency as a “sunlight deficiency” and reduced melatonin secretion as a result of “darkness deficiency” from overexposure to artificial blue light. The trend toward greater use of melatonin supplements has resulted in concern about its safety, especially higher doses, long-term use, and application in certain populations (e.g., children). This review aims to evaluate the recent data on melatonin’s mechanisms, its clinical uses beyond sleep, safety concerns, and a thorough summary of therapeutic considerations concerning dietary supplementation, including the different formats available (animal, synthetic, and phytomelatonin), dosing, timing, contraindications, and nutrient combinations.

The boosting effects of melatonin on the expression of related genes to oocyte maturation and antioxidant pathways: a polycystic ovary syndrome- mouse model

Background

Melatonin, as a free radical scavenger exhibiting genomic actions, regulates the antioxidant genes expression and apoptosis mechanisms. In polycystic ovary syndrome (PCOS) patients, an imbalance between free radicals and antioxidants in follicular fluid leads to oxidative stress, aberrant folliculogenesis, and intrinsic defects in PCOS oocytes. In this experimental mouse model study, oocytes of PCOS and the control groups were cultured in different melatonin concentrations (10− 5, 10− 6, and 10− 7 M) to investigate the expression of oocyte maturation-related genes (Gdf9/Bmp15), antioxidant-related genes (Gpx1/Sod1), apoptotic biomarkers (Bcl2/Bax) and total intracellular ROS levels.

Results

Gdf9 and Bmp15, Gpx1 and Sod1 were up-regulated in PCOS and control oocytes cultured in all melatonin concentrations compared to those cultured in IVM basal medium (P < 0.05). A significant decrease in the total ROS level was observed in all groups cultured in the supplemented cultures. Melatonin increased Bcl2 and decreased Bax gene expression in PCOS and control oocytes compared to non-treated oocytes.

Conclusions

Melatonin increased antioxidant gene expression and regulated the apoptosis pathway, effectively reducing the adverse effects of culture conditions on PCOS oocytes. Furthermore, it influenced the expression of oocyte maturation-related genes in PCOS, providing valuable support during the IVM process.

"LONG COVID"-A hypothesis for understanding the biological basis and pharmacological treatment strategy

Infection of humans with SARS‐CoV‐2 virus causes a disease known colloquially as “COVID‐19” with symptoms ranging from asymptomatic to severe pneumonia. Initial pathology is due to the virus binding to the ACE‐2 protein on endothelial cells lining blood vessels and entering these cells in order to replicate. Viral replication causes oxidative stress due to elevated levels of reactive oxygen species. Many (~60%) of the infected people appear to have eliminated the virus from their body after 28 days and resume normal activity. However, a significant proportion (~40%) experience a variety of symptoms (loss of smell and/or taste, fatigue, cough, aching pain, “brain fog,” insomnia, shortness of breath, and tachycardia) after 12 weeks and are diagnosed with a syndrome named “LONG COVID.” Longitudinal clinical studies in a group of subjects who were infected with SARS‐CoV‐2 have been compared to a non‐infected matched group of subjects. A cohort of infected subjects can be identified by a battery of cytokine markers to have persistent, low level grade of inflammation and often self‐report two or more troubling symptoms. There is no drug that will relieve their symptoms effectively. It is hypothesized that drugs that activate the intracellular transcription factor, nuclear factor erythroid‐derived 2‐like 2 (NRF2) may increase the expression of enzymes to synthesize the intracellular antioxidant, glutathione that will quench free radicals causing oxidative stress. The hormone melatonin has been identified as an activator of NRF2 and a relatively safe chemical for most people to ingest chronically. Thus, it is an option for consideration of re‐purposing studies in “LONG COVID” subjects experiencing insomnia, depression, fatigue, and “brain fog” but not tachycardia. Appropriately designed clinical trials are required to evaluate melatonin.

Melatonin ameliorates endocrine dysfunction and defective sperm integrity associated with high-fat diet-induced obesity in male Wistar rats

Obesity (OBS) has been established as a link to male hypogonadism with consequent infertility. Previous studies have shown that melatonin (MEL) modulates hypothalamic-pituitary-gonadal function. The present study therefore investigated the hypothesis that MEL supplementation would attenuate spermatogenic and steroidogenic dysfunctions associated with obesity induced by high-fat diet (HFD). Twenty-four adult male Wistar rats (n = 6/group) were used: control group received vehicle (normal saline), obese group received 40% high-fat diet and distilled water, MEL-treated group received MEL (4 mg/kg), and OBS + MEL group received MEL and 40% HFD and the treatment lasted for 12 weeks. HFD caused increased body weight, glucose intolerance, plasma triglyceride and low-density lipoprotein cholesterol/ very low-density lipoprotein cholesterol and malondialdehyde, as well as decreased antioxidant capacity, high-density lipoprotein cholesterol, gonadotrophin-releasing hormone, follicle-stimulating hormone and testosterone and altered sperm parameters. However, all these alterations were attenuated when supplemented with MEL. Taken together, these results indicate that HFD exposure causes endocrine dysfunction and disrupted sperm parameters in obese animals, which are accompanied by lipid peroxidation/defective antioxidant capacity. In addition, the present results suggest that melatonin supplementation restores endocrine function and sperm integrity in obese rat model by suppression of oxidative stress-dependent mechanism.

The effect of oral melatonin supplementation on MT-ATP6 gene expression and IVF outcomes in Iranian infertile couples: a nonrandomized controlled trial

This study aims to evaluate the effect of melatonin supplementation on the outcomes of in vitro fertilization (IVF) and mitochondrial adenosine triphosphate production (MT-ATP6) gene expression in Iranian infertile couples. A single-blind nonrandomized controlled trial was conducted, recruiting 90 infertile couples who underwent IVF at an infertility center in Tehran, Iran. Patients who were assigned to the intervention group received melatonin as a supplementation to the standard controlled ovarian stimulation (COS). The control group received a COS protocol only. Primary outcome was the mRNA level of the MT-ATP6 gene in cumulus cells of ovarian follicles. Secondary outcomes were the mean number of mature oocytes retrieved, the embryo quality, and biochemical and clinical pregnancy rates. The mRNA level of the MT-ATP6 gene in cumulus cells between intervention and control groups was not statistically different (0.931 vs.1; P ˃ 0.05). The mean number of poor-quality embryos was significantly lower in the intervention group than that in the control group (0.27 vs. 0.80; P = 0.028). The biochemical and clinical pregnancy rates were higher in the intervention group (24% vs. 14%, P = 0.089, and 14% vs. 7%, P = 0.302, respectively); however, the difference was not significant. Melatonin supplementation did not increase the odds of clinical pregnancy and the number of mature oocytes retrieved, but significantly reduced the number of low-quality embryos. More extensive studies focusing on the level of MT-ATP6 gene expression in the oocyte or blastomere cells may further elucidate the effect of supplementation with melatonin in infertile couples who have poor clinical outcomes. Trial registration: Current Controlled Trials: IRCT2015042912307N4.

Reprogramming of glucose metabolism of cumulus cells and oocytes and its therapeutic significance

The aim of this review is to summarize our current understanding of the molecular mechanism for the glucose metabolism, especially pyruvate dehydrogenase (PDH), during oocyte maturation, as well as future perspectives of therapeutic strategies for aging focusing on metabolic regulation between aerobic glycolysis and the tricarboxylic acid (TCA) cycle/oxidative phosphorylation (OXPHOS). Each keyword alone or in combination was used to search from PubMed. Glucose metabolism is a dynamic process involving "On" and "Off" switches by the pyruvate dehydrogenase kinase (PDK)-PDH axis, which is crucial for energy metabolism and mitochondrial efficiency in cumulus cell differentiation and oocyte maturation. Activation of PDK suppresses the conversion of pyruvate to acetyl-coenzyme A (acetyl-CoA) through the inactivation of PDH, which allows the cumulus cells to supply sufficient amounts of pyruvate, lactate, and nicotinamide adenine dinucleotide phosphate (NADPH) to the oocytes. On the other hand, inactivation of PDK in oocytes can produce adenosine triphosphate (ATP) through a metabolic shift from aerobic glycolysis to the TCA cycle/OXPHOS. The metabolic balance between aerobic glycolysis and TCA cycle/OXPHOS presents us with a number of enzymes, ligands, receptors, and antioxidants that are potential therapeutic targets, some of which have already been successfully pursued to improve fertility outcomes. However, there are also many reports that question their efficacy. In conclusion, understanding the molecular mechanisms involved in the PDK-PDH axis is a crucial step to advance in novel therapeutic strategies to improve oocyte quality.

Roles of melatonin in the teleost ovary: A review of the current status

Melatonin, the neurohormone mainly synthesized in and secreted from the pineal gland of vertebrates following a circadian rhythm, is an important factor regulating various physiological processes, including reproduction. Recent data indicate that melatonin is also synthesized in the ovary and that it acts directly at the level of the ovary to modulate ovarian physiology. In some teleosts, melatonin is reported to affect ovarian steroidogenesis. The direct action of melatonin on the ovary could be a possible factor promoting oocyte maturation in teleosts. A role for melatonin in follicle rupture during ovulation in the teleost medaka has recently emerged. In addition, melatonin is suggested to affect oocyte maturation by its antioxidant activity. However, the molecular mechanisms underlying these direct effects of melatonin are largely unknown.

Research Hot Spots and Trends on Melatonin From 2000 to 2019

Research on melatonin remains one of the major hot spots in the field of disease treatment, but relevant data are numerous. The purpose of this study was to quantitatively and qualitatively analyze the progress of melatonin research through the method of bibliometrics and to predict hot spots and trends in melatonin research. This study retrieved all the studies on melatonin from 2000 to 2019 in the Web of Science and PubMed and analysed the publishing trends in the literature on a bibliometric online analysis platform and CiteSpace software. The research results were also visually analysed to summarize melatonin research hot spots through gCLUTO and pubMR. The study retrieved a total of 20,351 publications, of which the number of US publications ranked first, accounting for 21.46%, with the greatest impact (centrality = 0.31). The University of Texas Health Science Center at San Antonio and Harvard University had the highest average number of citations at 43.19 and 33.96, respectively. Journal of Pineal Research had the highest average number of citations in 2,993 journals. Professor Reiter made the largest contribution to this area. We further analysed 100 highly cited articles for clinical applications and ongoing related clinical drug trials based on the first hot spot. We systematically analysed melatonin for nearly 20 years while predicting the main research trends in the future, which may provide new directions and ideas for melatonin research. The structure and normal physiological functions of melatonin have been intensively studied in the past few years. And clinical application research and target of melatonin treatment for different diseases and target-based drug design will certainly become the focus of melatonin research.

Anti-Cancer Effect of Melatonin via Downregulation of Delta-like Ligand 4 in Estrogen-Responsive Breast Cancer Cells

BACKGROUND

The Notch signaling pathway has a key role in angiogenesis and Delta - Like Ligand 4 (DLL4) is one of the main ligands of Notch involved in cell proliferation in sprouting vessels.

OBJECTIVE

In this study, we aimed to evaluate the expression of DLL4 in primary breast tumors and to examine the effect of melatonin on DLL4 expression in vitro.

METHODS

Eighty-five breast tumor and paired adjacent non-tumor tissue samples were collected. Apoptosis assay was performed on breast cancer cells to evaluate melatonin effects. Western blot and quantitative RT-PCR were used to measure DLL4 expression. Then, we investigated the effect of melatonin on the expression of DLL4 in four breast cancer cell lines at RNA and protein levels. We also performed a probabilistic neural network analysis to study genes closely associated with DLL4 expression.

RESULTS

Our results showed a significantly higher expression of DLL4 in tumor tissues compared to non-tumor tissues (P = 0.027). Melatonin treatment substantially attenuated DLL4 expression in BT474 and MCF-7 cells, but not in SK-BR-3 and MDA-MB-231 cells. Also, melatonin induced apoptosis in all four cell lines. Network analysis revealed a set of 15 genes that had close association and interaction with DLL4. DLL4 was overexpressed in breast cancer tissues as compared to the non-tumor tissues.

CONCLUSION

It can be concluded that melatonin treatment attenuated DLL4 expression only in estrogen- responsive breast cancer cells and is able to induce apoptosis in breast cancer cells.

Ameliorative effect of melatonin on apoptosis, DNA fragmentation, membrane integrity and lipid peroxidation of spermatozoa in the idiopathic asthenoteratospermic men: In vitro

Fertility loss, recurrent spontaneous abortion and poor outcome in assisted reproductive techniques (ART) have been associated with DNA fragmentation. This work was achieved to evaluate the protective role of melatonin versus apoptosis, DNA fragmentation, membrane integrity and lipid peroxidation of spermatozoa from men with asthenoteratozoospermia (ATS). Some researchers maintain that melatonin can serve as a remedy for apoptosis induction, and it has an impressive effect on boosting the quality and quantity of spermatozoa. For this purpose, semen samples were collected from 50 ATS men and they were divided into control and melatonin (6 mM) groups at 2, 4, 6 and 24 hr. Concentrating on the reasons for apoptosis is an arduous process, but in the present study for this evaluation mitochondrial membrane potential (MMP), DNA fragmentation by TUNEL and sperm chromatin dispersion (SCD) methods and lipid peroxidation were carried out. Also, sperm viability was performed. In the control group, MDA, TUNEL-positive and SCD were significantly increased but viability and MMP of spermatozoa were significantly decreased. Moreover, in the melatonin group, TUNEL-positive, SCD and MDA levels were significantly decreased and viability and MMP significantly increased, compared to the control group. In outcome, melatonin prescription paves the way for apoptosis down-regulating in the ATS men.

The protective effect of melatonin on radiofrequency electromagnetic fields of mobile phone-induced testicular damage in an experimental mouse model

Radiofrequency electromagnetic radiation (RF-EMR) from mobile devices has undesirable effects on the male reproductive organs. Melatonin with antioxidant potential can help to prevent these damages. Therefore, the aim of this study was to evaluate the protective effect of melatonin on testicular damage induced by RF-EMR of mobile phone. In this experimental study, 32 adult male BALB/c mice were divided randomly into four groups: control, melatonin (2 mg/kg, for 30 consecutive days, intraperitoneally), RF-EMR (900 MHz, 100 to 300 MT, 54 to 160 W/m) (4 hr per day, whole body) and melatonin + RF-EMR groups. One day after the last prescription were evaluated oxidative stress parameters, testosterone level and histopathological assays of the testis. EMR of mobile phone led to the induction of oxidative stress, testicular tissue damage and decreased testosterone. Treatment with melatonin improved oxidative stress parameters such as MDA and GSH, and testis injury score, increased the thickness of the germinal epithelial thickness and diameter of the seminiferous tubule, and decreased testosterone hormone in the EMR-exposed mice, and these differences were significant(p < .05). Data showed that melatonin with its antioxidant property can decrease oxidative damage induced by RF-EMR of mobile phones on testis tissue.

El-Taieb M, N. Fares N, M. Fayed H, Toghan R, M. Ibrahim H. Men with idiopathic oligoasthenoteratozoospermia exhibit lower serum and seminal plasma melatonin levels: Comparative effect of night-light exposure with fertile males

Melatonin is a darkness hormone secreted by the pineal gland, which serves a role in idiopathic oligoasthenoteratozoospermia (iOAT). The present study aimed to evaluate the seminal plasma and serum melatonin levels of 50 patients with iOAT and 50 normal fertile controls and the effects of exposure to light at night on semen parameters. Semen analyses were performed according to the World Health Organization 2010 guidelines. Measurements of serum and seminal plasma melatonin, serum TSH, FT3, FT4, free testosterone, prolactin, FSH and LH were performed using ELISA. The overall results revealed that the serum and seminal plasma levels of melatonin were lower in patients with iOAT compared with the control subjects (P=0.0004 and 0.01, respectively). Patients with iOAT who were exposed to light at night exhibited lower serum and seminal plasma melatonin levels compared with those who were not exposed to light at night (P<0.0001 and 0.02, respectively). Additionally, similar significant differences were identified in control subjects exposed to light at night when compared to non-exposed controls. There was a significantly positive correlation between serum melatonin levels and sperm motility in the entire iOAT patient cohort (r=0.614; P<0.0001) and a significantly positive correlation between the serum and seminal plasma melatonin levels in the non-exposed iOAT patient subgroup (r=0.753; P<0.001). Thus, darkness and sleep at night may improve the semen parameters of patients with iOAT, as evidenced by the effects of light exposure at night on the serum and seminal plasma levels of melatonin and, consequently, on semen parameters.

Gut microbial metabolism of dietary fibre protects against high energy feeding induced ovarian follicular atresia in a pig model

To investigate the effects of dietary fibre on follicular atresia in pigs fed a high-fat diet, we fed thirty-two prepubescent gilts a basal diet (CON) or a CON diet supplemented with 300 g/d dietary fibre (fibre), 240 g/d soya oil (SO) or both (fibre + SO). At the 19th day of the 4th oestrus cycle, gilts fed the SO diet showed 112 % more atretic follicles and greater expression of the apoptotic markers, Bax and caspase-3, and these effects were reversed by the fibre diet. The abundance of SCFA-producing microbes was decreased by the SO diet, but this effect was reversed by fibre treatment. Concentrations of serotonin and melatonin in the serum and follicular fluid were increased by the fibre diet. Overall, dietary fibre protected against high fat feeding-induced follicular atresia at least partly via gut microbiota-related serotonin-melatonin synthesis. These results provide insight into preventing negative effects on fertility in humans consuming a high-energy diet.

Redox Biology of Human Cumulus Cells: Basic Concepts, Impact on Oocyte Quality, and Potential Clinical Use

Significance: Four decades have passed since the first successful human embryo conceived from a fertilization in vitro. Despite all advances, success rates in assisted reproduction techniques still remain unsatisfactory and it is well established that oxidative stress can be one of the major factors causing failure in in vitro fertilization (IVF) techniques. Recent Advances: In the past years, researchers have been shown details of the supportive role CCs play along oocyte maturation, development, and fertilization processes. Regarding redox metabolism, it is now evident that the synergism between gamete and somatic CCs is fundamental to further support a healthy embryo, since the oocyte lacks several defense mechanisms that are provided by the CCs. Critical Issues: There are many sources of reactive oxygen species (ROS) in the female reproductive tract in vivo that can be exacerbated (or aggravated) by pathological features. While an imbalance between ROS and antioxidants can result in oxidative damage, physiological levels of ROS are essential for oocyte maturation, ovulation, and early embryonic growth where they act as signaling molecules. At the event of an assisted reproduction procedure, the cumulus/oophorus complex is exposed to additional sources of oxidative stress in vitro. The cumulus cells (CCs) play essential roles in protecting the oocytes from oxidative damage. Future Directions: More studies are needed to elucidate redox biology in human CCs and oocyte. Also, randomized controlled trials will identify possible benefits of in vivo or in vitro administration of antioxidants for patients seeking IVF procedure.

Melatonin and Female Reproduction: An Expanding Universe

For more than a half century the hormone melatonin has been associated with vertebrate reproduction, particularly in the context of seasonal breeding. This association is due in large measure to the fact that melatonin secretion from the pineal gland into the peripheral circulation is a nocturnal event whose duration is reflective of night length, which of course becomes progressively longer during winter months and correspondingly shorter during the summer months. The nocturnal plasma melatonin signal is conserved in essentially all vertebrates and is accessed not just for reproductive rhythms, but for seasonal cycles of metabolic activities, immune functions, and behavioral expression. A vast literature on melatonin and vertebrate biology has accrued over the past 60 years since melatonin's discovery, including the broad topic of animal reproduction, which is far beyond the scope of this human-focused review. Although modern humans in the industrialized world appear in general to have little remaining reproductive seasonality, the relationships between melatonin and human reproduction continue to attract widespread scientific attention. The purpose of this chapter is to draw attention to some newer developments in the field, especially those with relevance to human fertility and reproductive medicine. As the vast majority of studies have focused on the female reproductive system, a discussion of the potential impact of melatonin on human male fertility will be left for others.

Observation of Parthanatos Involvement in Diminished Ovarian Reserve Patients and Melatonin's Protective Function Through Inhibiting ADP-Ribose (PAR) Expression and Preventing AIF Translocation into the Nucleus

Diminished ovarian reserve (DOR) is characterized by the depletion of the ovarian pool, which leads to reductions in oocyte quality and quantity. Studies have suggested that ovarian reserve or ovarian aging is tightly related to apoptosis. However, the cell death mechanism is not comprehensively understood. Parthanatos, a type of poly [ADP-ribose] polymerase 1(PARP1)-dependent and apoptosis-inducing factor (AIF)-mediated cell death, plays a crucial role in various disorders. In the present study, we aimed to investigate whether parthanatos is involved in the pathogenesis of DOR. We recruited 40 patients (20 DOR patients and 20 normal ovarian reserve (NOR) patients) and examined PAR expression and AIF translocation in their isolated cumulus GCs (granulosa cells) by fluorescence microscopy. Our results demonstrated that PAR expression and AIF nuclear translocation were significantly higher in cumulus GCs of DOR patients, suggesting that PARP1-dependent cell death may be associated with DOR pathophysiology. Moreover, we tested the protective function of melatonin on hydrogen peroxide (H₂O₂)-induced parthanatos in human ovarian cancer (IGROV1) cells. Our results demonstrated that H₂O₂ treatment of IGROV1 cells led to excessive protein PARylation and AIF translocation into the nuclei. Melatonin effectively inhibits PARylation, blocks translocation of AIF into the nucleus, and consequently decreases the risk of parthanatos in cumulus GCs.

Insufficiency of melatonin in follicular fluid is a reversible cause for advanced maternal age-related aneuploidy in oocytes

Age-related decline in female fertility is a common feature that occurs in the fourth decade of women as a result of a reduction in both oocyte quality and quantity [1]. However, strategies to prevent the deterioration of maternal aged oocytes and relevant mechanisms are still underexplored. Here, we find that the reduced abundance of melatonin in the follicular fluid highly correlates with the advanced maternal age-related aneuploidy. Of note, we show that exposure of oocytes from aged mice both in vitro and in vivo to exogenous melatonin not only eliminates the accumulated reactive oxygen species-induced DNA damage and apoptosis, but also suppresses the occurrence of aneuploidy caused by spindle/chromosome defect that is frequently observed in aged oocytes. Importantly, we reveal that melatonin supplementation reverses the defective phenotypes in aged oocytes through a Sirt1/Sod2-dependent mechanism. Inhibition of Sirt1 activity abolishes the melatonin-mediated improvement of aged oocyte quality. Together our findings provide evidence that supplementation of melatonin is a feasible way to protect oocytes from advanced maternal age-related meiotic defects and aneuploidy, demonstrating the potential for improving the quality of oocytes from aged women and the efficiency of assisted reproductive technology.

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Melatonin abundance in the follicular fluid declines with age in the mouse.

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In vitro treatment of aged oocytes with melatonin eliminates the excessive ROS and reduces the occurrence of aneuploidy.

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In vivo administration of advanced-age mice with melatonin protects oocytes from spindle/chromosome defects and aneuploidy.

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Melatonin supplementation reverses the meiotic defects in aged oocytes through activation of Sirt1/Sod2 pathway.

Effects of Melatonin Administration on Chemical Pregnancy Rates of Polycystic Ovary Syndrome Patients Undergoing Intrauterine Insemination: A Randomized Clinical Trial

Background

Oxidative stress as a potential cause of poor oocyte quality can influence a female's reproductive system. This study aimed to investigate the effects of melatonin on chemical pregnancy rates of a significant number of polycystic ovary syndrome (PCOS) patients undergoing intrauterine insemination (IUI).

Materials and Methods

In this double-blinded randomized clinical trial (RCT) study, the samples included 198 PCOS patients fulfilling the inclusion criteria and undergoing the IUI treatment. On the third day of menstruation, a 3-mg melatonin tablet or its placebo was given to the patients according to the randomized study protocol; this prescription was continued until the day of human chorionic gonadotropin (hCG) administration. The current study attempted primarily to scrutinize the effect of melatonin administration on the rate of chemical pregnancy and mature follicles during the IUI treatment cycle, and secondarily to determine the endometrial thickness (ET) on the day of IUI.

Results

The mean age of the participants in the study was 28.9 ± 5.5 years. The chemical pregnancy rate in the group receiving melatonin was about 32%, when it was 18% in the control group (P=0.012). Furthermore, it was concluded that the addition of melatonin to the treatment cycle of PCOS individuals could significantly improve the ET after the treatment (P<0.001).

Conclusion

The results of this study demonstrated that the treatment of PCOS patients undergoing IUI with melatonin significantly improves the rate of chemical pregnancy (Registration number: IRCT2017021132489N1).

Myo-inositol and D-chiro-inositol (40:1) reverse histological and functional features of polycystic ovary syndrome in a mouse model

Mice exposed to continuous light undergo functional and histological changes that mimic those of human Polycystic Ovary Syndrome (PCOS). We herein induced the syndrome by exposing 30-day-old females to 10 weeks of permanent light. Ovarian morphology and histology, as well as reproductive parameters (time of observed pregnancy/delivery) were investigated. Ovaries of PCOS-modeled mice showed lack of tertiary follicles and corpora lutea, altered ovarian architecture, and increased thickness of the theca layer. When mice were returned to a normal light-dark regimen for 10 days, a slight, spontaneous improvement occurred, whereas a quick and almost complete recovery from PCOS signs and symptoms was obtained by treating animals with a daily supplementation of 420 mg/kg myo-inositol and D-chiro-inositol (MyoIns/DCIns) in a 40:1 molar ratio. Namely, ovaries from mice treated by this protocol recovered normal histological features and a proper ratio of theca/granulosa cell layer thickness (TGR), suggesting that the androgenic phenotype was efficiently reversed. Indeed, we identified TGR as a useful index of PCOS, as its increase in PCOS-modeled mice correlated linearly with reduced reproductive capability ( r = 0.75, p < 0.0001). Mice treated with a 40:1 formula regained low TGR values and faster recovery of their fertility, with a physiological delivery time after mating. On the other hand, a higher D-chiro-inositol treatment formula, such as MyoIns versus DCIns 5:1, was ineffective or even had a negative effect on clinical-pathological outcomes.

Protective Effects of Melatonin Against Zearalenone Toxicity on Porcine Embryos in vitro

Zearalenone (ZEA) is an estrogenic mycotoxin produced by Fusarium fungi commonly found in corn, wheat, and other cereals which can infect food and feed commodities, and ZEA mainly has reproductive toxicity which causes widely reproductive disorders in pigs and other animals. However, the toxicity and the functional ways of ZEA on early embryo development is still unclear. In present study we showed that exposure to ZEA (10 μM) significantly decreased the 2-cell and blastocyst developmental rate in porcine early embryos in vitro. ZEA treatment resulted in the occurrence of oxidative stress, showing with increased reactive oxygen species (ROS) level, following with aberrant mitochondrial distribution. Moreover, we found positive signals of γH2A.X in the ZEA-treated embryos, indicating that ZEA induced DNA damage, and the increased autophagy confirmed this. These results suggested that ZEA induced oxidative stress, which further caused mitochondria dysfunction and DNA damage on early embryonic development. We next investigated the effects of melatonin on the ZEA-treated embryo development, and we found that melatonin supplementation could significantly ameliorate ZEA-induced oxidative stress, aberrant mitochondria distribution and DNA damage. In all, our results showed that ZEA was toxic for porcine embryos cultured in vitro and melatonin supplementation could protect their development from the effects of ZEA.

Potential Marker Pathways in the Endometrium That May Cause Recurrent Implantation Failure

The aim of this prospective cohort study was to identify altered biologic processes in the endometrium that may be potential markers of receptive endometrium in patients with repeated implantation failure (RIF) as compared with fertile controls. The study was conducted in a university-affiliated in vitro fertilization (IVF) gynecology clinic and molecular biology and genetics laboratory. Healthy fertile controls (n = 24) and patients with RIF (n = 24) were recruited. Window of implantation gene profiling associated with RIF was performed. Six hundred forty-one differentially expressed genes were identified, and 44 pathways were found enriched. Upon clustering of the enriched pathways, 9 representative pathways were established. The important pathways that were identified included circadian rhythm, pathways in cancer, proteasome, complement and coagulation cascades, citrate cycle, adherens junction, immune system and inflammation, cell cycle, and renin-angiotensin system. The involvement of the circadian rhythm pathway and other related pathways may alter the endometrium's functioning to ultimately cause RIF. Furthermore, we found that the pathogenesis of RIF was multifaceted and that numerous processes were involved. We believe that a better understanding of the underlying mechanisms of RIF will ultimately give rise to better treatment opportunities and to better outcomes in IVF.

Female Reproductive Performance in the Mouse: Effect of Oral Melatonin

Although melatonin has some of the broadest ranges of actions on the physiology of vertebrates, especially on their reproductive processes, the mechanism by which melatonin regulates animal reproduction is still incompletely understood. This study was designed to determine the effect of oral melatonin on the reproductive performance of female mice. Female ICR mice (7 weeks old) were given melatonin-containing water (3, 30 and 300 μg/mL; melatonin) or water only (control) until 10 weeks of age. Then, some of the mice were successfully mated (confirmed by vaginal plugs), and the number of live births and their weights were recorded. Some mice were used for a histological analysis of the number of follicles in the ovaries. Others were used for oocyte collection after superovulation, and in vitro fertilization (IVF) was performed. The mRNA expression of the apopotosis-related genes (BAX, BCL2) in the IVF embryos were analyzed. After melatonin administration, the mice showed similar serum melatonin levels to that of the control. The number of antral follicles per mm² unit area in the 30 μg/mL melatonin-treated group (14.60) was significantly higher than that of the control (7.78), which was lower than that of the 3 μg/mL melatonin-treated group (12.29). The litter size was significantly higher in the 3 μg/mL melatonin-treated group (15.5) than in the control (14.3). After IVF, the hatched blastocyst formation rate in the 30 μg/mL melatonin-treated group (85.70%) was significantly higher than that of the control (72.10%), and it was the same for the BCL2/BAX expression ratio. Although oral melatonin did not appear to have an effect on the serum melatonin rhythm in the mouse, melatonin did increase litter size at the 3 μg/mL dose level, and improved the developmental competency of IVF embryos at the 30 μg/mL level.

Effect of exogenous melatonin and different photoperiods on oxidative status and antioxidant enzyme activity in Chhotanagpuri ewe

Aim:

The present study was conducted to evaluate the effect of exogenous melatonin under different photoperiods on oxidative status in Chhotanagpuri ewe.

Materials and Methods:

A total of 42 non-pregnant, non-lactating Chhotanagpuri ewe, having body weight ranging between 14.11±0.09 and 15.38±0.06 kg, were selected and were isolated from rams 2 months before melatonin administration. The selected animals were allocated randomly into seven groups, namely, Group I (normal control), Group II (long day [LD] control), Group III (LD+melatonin administration orally, 3 mg/day), Group IV (LD+melatonin administration subcutaneously, 1 mg/day), Group V (short day [SD] control), Group VI (SD+melatonin administration orally, 3 mg/day), and Group VII (SD+melatonin administration subcutaneously, 1 mg/day) comprising six animals in each group. Rams were then introduced into each group after completion of exogenous administration of melatonin. Blood samples with anticoagulant in vials were collected from each animal day before the start of the experiment and thereafter every month up to 5^th month. Hemolysate was prepared for estimation of oxidative stress parameters such as malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT).

Results:

It was observed that the level of MDA was significantly (p<0.05) higher in LD groups (Group II, III and IV) in comparison to control and SD groups (VI and VII) at 1^st month. MDA concentration after exogenous administration of melatonin was significantly (p<0.05) decreased in Group IV and VI in comparison to 1^st month. SOD was significantly (p<0.05) higher in SD groups (V, VI, and VII) at the 1^st month in comparison to 0 day. After exogenous administration of melatonin, SOD concentration was significantly (p<0.05) higher in Groups III and IV in comparison to 1^st month. CAT was significantly (p<0.05) higher in SD groups (V, VI, and VII) in comparison to control and LD groups. After exogenous administration of melatonin, CAT concentration was significantly (p<0.05) higher in Groups III, IV, VI, and VIII in comparison to Groups I, II, and V. At the 3^rd month, CAT concentration significantly (p<0.05) decreased in Groups III, IV, VI, and VII in comparison to 2^nd month of experiment. However, a decreasing trend of CAT was observed in all the groups from 3^rd to 5^th month.

Conclusion:

The present experiment revealed that exogenous melatonin was able to reduce significantly the level of MDA and increased the activity of SOD and CAT in Chhotanagpuri ewe.

Melatonin and health: an umbrella review of health outcomes and biological mechanisms of action

BACKGROUND

Our aims were to evaluate critically the evidence from systematic reviews as well as narrative reviews of the effects of melatonin (MLT) on health and to identify the potential mechanisms of action involved.

METHODS

An umbrella review of the evidence across systematic reviews and narrative reviews of endogenous and exogenous (supplementation) MLT was undertaken. The Oxman checklist for assessing the methodological quality of the included systematic reviews was utilised. The following databases were searched: MEDLINE, EMBASE, Web of Science, CENTRAL, PsycINFO and CINAHL. In addition, reference lists were screened. We included reviews of the effects of MLT on any type of health-related outcome measure.

RESULTS

Altogether, 195 reviews met the inclusion criteria. Most were of low methodological quality (mean -4.5, standard deviation 6.7). Of those, 164 did not pool the data and were synthesised narratively (qualitatively) whereas the remaining 31 used meta-analytic techniques and were synthesised quantitatively. Seven meta-analyses were significant with P values less than 0.001 under the random-effects model. These pertained to sleep latency, pre-operative anxiety, prevention of agitation and risk of breast cancer.

CONCLUSIONS

There is an abundance of reviews evaluating the effects of exogenous and endogenous MLT on health. In general, MLT has been shown to be associated with a wide variety of health outcomes in clinically and methodologically heterogeneous populations. Many reviews stressed the need for more high-quality randomised clinical trials to reduce the existing uncertainties.

The impact of melatonin on the sleep patterns of women undergoing IVF: a double blind RCT

STUDY QUESTION

Does melatonin result in a dose–response effect on sleep quality and daytime sleepiness in women undergoing IVF?

SUMMARY ANSWER

Melatonin, even when given at high doses twice per day, does not cause significant daytime sleepiness or change night time sleep quantity or quality.

WHAT IS KNOWN ALREADY

Melatonin is being increasingly used as an adjuvant therapy for women undergoing IVF owing to its antioxidative effects. It is widely considered to be sedative but there are scant objective data on the effects of melatonin on sleep in the setting of IVF.

STUDY DESIGN SIZE, DURATION

The study was a double-blind placebo-controlled randomized trial of 116 women recruited between September 2014 and September 2016.

PARTICIPANTS/MATERIALS, SETTING, METHOD

Women who were undergoing their first cycle of IVF at private IVF centers were recruited into the RCT and randomized to receive either placebo, 2 mg, 4 mg or 8 mg of melatonin, twice per day (BD) from Day 2 of their cycle until the day before oocyte retrieval. Each participant wore an accelerometer that provides an estimate of sleep and wake activity for up to 1 week of baseline and throughout treatment (up to 2 weeks). They also kept sleep diaries and completed a Karolinska sleepiness score detailing their night time sleep activity and daytime sleepiness, respectively.

MAIN RESULTS AND THE ROLE OF CHANCE

In total, 116 women were included in the intention-to-treat analysis (placebo BD (n = 32), melatonin 2 mg BD (n = 29), melatonin 4 mg BD (n = 26), melatonin 8 mg BD (n = 29)). There were no significant differences in daytime Karolinska sleepiness score between groups (P = 0.4), nor was there a significant dose–response trend (β=0.05, 95% CI −0.22–0.31, P = 0.7). There were no differences in objective measures of sleep quantity or quality, including wake after sleep onset time, sleep onset latency, and sleep efficiency before and after treatment or between groups. There was an improvement in subjective sleep quality scores from baseline to during treatment in all groups, except 8 mg BD melatonin: placebo (percentage change −13.3%, P = 0.01), 2 mg (−14.1%, P = 0.03), 4 mg (−8.6%, P = 0.01) and 8 mg (−7.8%, P = 0.07).

LIMITATIONS, REASONS FOR CAUTION

As this was a subset of a larger trial, the melatonin in ART (MIART) trial, it is possible that the sample size was too small to detect statistically significant differences between the groups.

WIDER IMPLICATIONS OF THE FINDINGS

While this study suggests that melatonin can be used twice per day at high doses to achieve sustained antioxidation effects, with the reassurance that this will not negatively impact daytime sleepiness or night time sleep habits, the sample size is small and may have missed a clinically significant difference. Nevertheless, our findings may have implications not only for future studies of fertility treatments (including meta-analyses), but also in other medical fields where sustained antioxidation is desired.

STUDY FUNDING/COMPETING INTERESTS

This study was funded by the Monash IVF Research and Education Foundation (PY12_15). S.F. is supported by the National Health and Medical Research Council (Postgraduate Scholarship APP1074342) and the Royal Australian and New Zealand College of Obstetricians and Gynaecologists Ella Macknight Memorial Scholarship. E.W. is supported by an National Health and Medical Research Council Program Grant (APP1113902). S.F., E.W., R.H., B.V., N.L., N.H., M.W., M.L., A.L., P.T., K.L. have nothing to declare. L.R. is a Minority shareholder in Monash IVF Group, has unrestricted grants from MSD®, Merck-Serono® and Ferring® and receives consulting fees from Ferring®. S.N.B. reports consulting fees from Johnson & Johnson Consumer Inc®, outside the submitted work.

TRIAL REGISTRATION NUMBER

This trial was prospectively registered with the Australian New Zealand Clinical Trials Registry (Project ID: ACTRN12613001317785).

TRIAL REGISTRATION DATE

27/11/2013

DATE OF FIRST PATIENT’S ENROLMENT

1/9/2014

External factors affecting fertility, and how to correct their impact

Fertility of both men and women has been negatively influenced by external factors and life style in recent decennia. Mechanisms of hormone disruption, oxidative damage, and epigenetic DNA changes play a pivotal role in this process. In Belgium, strict regulations have been imposed to reduce the exposure to xeno-estrogens, which has resulted in a partial recovery of sperm quality. At the other hand, more couples require in vitro fertilisation (IVF) whereby ovarian stimulation may be associated with epigenetic DNA hyper-methylation of follicular cells, and increased risk of carcinogenesis among offspring. In order to reduce the health risks for the offspring it is recommended to optimize the oxidative, epigenetic and metabolic situation of both parents by means of lifestyle adaptation, and the use of appropriate food supplementation before conception and during pregnancy.

Melatonin and Hippo Pathway: Is There Existing Cross-Talk?

Melatonin is an indolic hormone that regulates a plethora of functions ranging from the regulation of circadian rhythms and antioxidant properties to the induction and maintenance of tumor suppressor pathways. It binds to specific receptors as well as to some cytosolic proteins, leading to several cellular signaling cascades. Recently, the involvement of melatonin in cancer insurgence and progression has clearly been demonstrated. In this review, we will first describe the structure and functions of melatonin and its receptors, and then discuss both molecular and epidemiological evidence on melatonin anticancer effects. Finally, we will shed light on potential cross-talk between melatonin signaling and the Hippo signaling pathway, along with the possible implications for cancer therapy.

Melatonin protects oocyte quality from Bisphenol A-induced deterioration in the mouse

Bisphenol A (BPA) has been reported to adversely affect the mammalian reproductive system in both sexes. However, the underlying mechanisms regarding how BPA disrupts the mammalian oocyte quality and how to prevent it have not been fully defined. Here, we document that BPA weakens oocyte quality by impairing both oocyte meiotic maturation and fertilization ability. We find that oral administration of BPA (100 μg/kg body weight per day for 7 days) compromises the first polar body extrusion (78.0% vs 57.0%, P<.05) by disrupting normal spindle assembly, chromosome alignment, and kinetochore-microtubule attachment. This defect could be remarkably ameliorated (76.7%, P<.05) by concurrent oral administration of melatonin (30 mg/kg body weight per day for 7 days). In addition, BPA administration significantly decreases the fertilization rate of oocytes (87.2% vs 41.1%, P<.05) by reducing the number of sperm binding to the zona pellucida, which is consistent with the premature cleavage of ZP2 as well as the mis-localization and decreased protein level of ovastacin. Also, the localization and protein level of Juno, the sperm receptor on the egg membrane, are strikingly impaired in BPA-administered oocytes. Finally, we show that melatonin administration substantially elevates the in vitro fertilization rate (63.0%, P<.05) by restoring above defects of fertilization proteins and events, which might be mediated by the improvement of oocyte quality via reduction of ROS levels and inhibition of apoptosis. Collectively, our data reveal that melatonin has a protective action against BPA-induced deterioration of oocyte quality in mice.

The Effects of Adjuvant Therapies on Embryo Transfer Success

BACKGROUND

Many adjuvant therapies are employed during IVF treatment in an attempt to improve outcomes. The objective of our study was to evaluate the impact of thirteen adjuvants (Intralipid, steroids, melatonin, coenzyme Q10, Filgrastim, testosterone, DHEA, growth hormone, antibiotics, hCG infusion, aspirin, enoxaparin/heparin and dopamine agonists) on the success of embryo transfers.

METHODS

This is a retrospective cohort study of all embryo transfers between January 2010 and April 2015 from a multi-site IVF clinic. To ensure data independence, random number was applied to each included transfer and used to pick an individual transfer for each patient (n=13,372). Outcomes were clinical pregnancy, live birth and pregnancy loss. Univariate comparison with Chi square testing and logistic regression analysis were used. The level of significance was p<0.05.

RESULTS

Steroid use was significantly associated with both reduced clinical pregnancy loss (aOR 0.39, CI 0.19-0.76) and improved live birth rates (aOR 1.40, CI 1.11-1.77). While aspirin was associated with improved live birth rates (aOR 1.48, CI 1.08-2.02), melatonin was linked with reduced rates (aOR 0.66, CI 0.45-0.96). Analyses for all other adjuvant therapies did not reach statistical significance after logistic regression.

CONCLUSION

Many of the interventions investigated in this study fail to significantly demonstrate any effects on the success of embryo transfers. Our analysis results show negative effects with the use of melatonin; however, use of aspirin or steroids demonstrated promising, potentially beneficial outcomes. Additional exploration is needed to guide evidence-based practice.

Melatonin in the management of perinatal hypoxic-ischemic encephalopathy: light at the end of the tunnel?

Perinatal hypoxic-ischemic encephalopathy (HIE) affects one to three per 1,000 live full-term births and can lead to severe and permanent neuropsychological sequelae, such as cerebral palsy, epilepsy, mental retardation, and visual motor or visual perceptive dysfunction. Melatonin has begun to be contemplated as a good choice in order to diminish the neurological sequelae from hypoxic-ischemic brain injury. Melatonin emerges as a very interesting medication, because of its capacity to cross all physiological barriers extending to subcellular compartments and its safety and effectiveness. The purpose of this commentary is to detail the evidence on the use of melatonin as a neuroprotection agent. The pharmacologic aspects of the drug as well as its potential neuroprotective characteristics in human and animal studies are described in this study. Melatonin seems to be safe and beneficial in protecting neonatal brains from perinatal HIE. Larger randomized controlled trials in humans are required, to implement a long-awaited feasible treatment in order to avoid the dreaded sequelae of HIE.

How to Achieve High-Quality Oocytes? The Key Role of Myo-Inositol and Melatonin

Assisted reproductive technologies (ART) have experienced growing interest from infertile patients seeking to become pregnant. The quality of oocytes plays a pivotal role in determining ART outcomes. Although many authors have studied how supplementation therapy may affect this important parameter for both in vivo and in vitro models, data are not yet robust enough to support firm conclusions. Regarding this last point, in this review our objective has been to evaluate the state of the art regarding supplementation with melatonin and myo-inositol in order to improve oocyte quality during ART. On the one hand, the antioxidant effect of melatonin is well known as being useful during ovulation and oocyte incubation, two occasions with a high level of oxidative stress. On the other hand, myo-inositol is important in cellular structure and in cellular signaling pathways. Our analysis suggests that the use of these two molecules may significantly improve the quality of oocytes and the quality of embryos: melatonin seems to raise the fertilization rate, and myo-inositol improves the pregnancy rate, although all published studies do not fully agree with these conclusions. However, previous studies have demonstrated that cotreatment improves these results compared with melatonin alone or myo-inositol alone. We recommend that further studies be performed in order to confirm these positive outcomes in routine ART treatment.