Control of Hormone Release During Lactation

The impact of pregnancy-related hormonal and physiological changes on antiseizure medications: expert perspective

INTRODUCTION

Epilepsy is a disorder of recurrent, unprovoked seizures affecting approximately 15 million individuals of childbearing potential worldwide. Patients with epilepsy rely on regular daily therapy with antiseizure medications (ASMs). Furthermore, ASMs are also prescribed for other neuropsychiatric indications (e.g. bipolar disorder, pain, migraines) with over 2% of the pregnancies in the United States involving prenatal exposure to ASMs.

AREAS COVERED

ASM concentrations are affected by hormonal and physiological changes in pregnancy, including increases in renal and hepatic blood flow, decreased protein binding, and changes in enzyme activity. Clearance changes typically reverse within a few weeks after delivery. During pregnancy, many ASMs, such as lamotrigine, levetiracetam, and oxcarbazepine, should have serum concentrations monitored and doses increased to maintain the individualized target range for seizure control. ASMs metabolized via glucuronidation, primarily lamotrigine, undergo marked increases in clearance throughout pregnancy, requiring about 3-fold the pre-pregnancy daily dose by delivery. Postpartum, ASM doses are usually decreased over several weeks to prevent drug toxicity.

EXPERT OPINION

In the future, the development of a physiologically-based pharmacokinetic model for various ASMs may enable empiric dose adjustments in pregnancy without the difficulties of frequent therapeutic drug monitoring.

Effect of Puberty, Menstruation, Pregnancy, Lactation, and Menopause on Chronic Urticaria Activity

BACKGROUND

Chronic urticaria (CU) is a systemic disorder which is characterized by recurrent wheals and/or angioedema lasting more than 6 weeks. Sex hormones have been suggested to play a role in CU pathogenesis, however, their clinical implications have not been adequately described in the literature.

OBJECTIVE

To determine whether conditions that change sex hormone levels such as puberty, menstruation, pregnancy, breastfeeding, and menopause affect the course of CU.

METHODS

This cross-sectional questionnaire study was conducted on female CU patients at Okmeydani Training and Research Hospital UCARE Center between 2016 and 2017. The open-ended questionnaire consisted of questions evaluating the effects of hormonal changes on disease course.

RESULTS

A total of 111 female CU patients were included in the analysis. During the perimenstrual period, CU symptoms worsened in 29% of patients but improved in 4.8%. The disease course did not change in the majority of patients during puberty, pregnancy, lactation, or menopause (100%, 96%, 83.8%, and 95.6%, respectively).

CONCLUSIONS

Contrary to expectations, a change in sex hormone levels had no effect on the course of CU in the majority of cases. However, disease activity increased in one-third of CU patients during the perimenstrual period.

Pharmaceutical treatment of bone loss: From animal models and drug development to future treatment strategies

Animal models are fundamental to advance our knowledge of the underlying pathophysiology of bone loss and to study pharmaceutical countermeasures against it. The animal model of post-menopausal osteoporosis from ovariectomy is the most widely used preclinical approach to study skeletal deterioration. However, several other animal models exist, each with unique characteristics such as bone loss from disuse, lactation, glucocorticoid excess, or exposure to hypobaric hypoxia. The present review aimed to provide a comprehensive overview of these animal models to emphasize the importance and significance of investigating bone loss and pharmaceutical countermeasures from perspectives other than post-menopausal osteoporosis only. Hence, the pathophysiology and underlying cellular mechanisms involved in the various types of bone loss are different, and this might influence which prevention and treatment strategies are the most effective. In addition, the review sought to map the current landscape of pharmaceutical countermeasures against osteoporosis with an emphasis on how drug development has changed from being driven by clinical observations and enhancement or repurposing of existing drugs to today's use of targeted anti-bodies that are the result of advanced insights into the underlying molecular mechanisms of bone formation and resorption. Moreover, new treatment combinations or repurposing opportunities of already approved drugs with a focus on dabigatran, parathyroid hormone and abaloparatide, growth hormone, inhibitors of the activin signaling pathway, acetazolamide, zoledronate, and romosozumab are discussed. Despite the considerable progress in drug development, there is still a clear need to improve treatment strategies and develop new pharmaceuticals against various types of osteoporosis. The review also highlights that new treatment indications should be explored using multiple animal models of bone loss in order to ensure a broad representation of different types of skeletal deterioration instead of mainly focusing on primary osteoporosis from post-menopausal estrogen deficiency.

Breastfeeding and the patient's perspective

PURPOSE

The purpose of this article is to summarize available data on breastfeeding in patients with a cancer diagnosis.

MATERIALS AND METHODS

A review of available literature in the MEDLINE database was performed and the data summarized. In addition, two patient interviews were conducted to gain insight into the patient perspective.

RESULTS

Breastmilk is the nutritional standard for human infants and understanding the implications of a cancer diagnosis on lactation is important in optimizing maternal and infant outcomes. Though limited, available data suggest that breastfeeding may be a safe and appropriate option for some patients undergoing treatment of a malignancy.

CONCLUSIONS

Patient experiences with breastfeeding in the setting of a cancer diagnosis vary widely, and depend on the type of malignancy, the timing of the diagnosis, and the indicated treatment. Breastfeeding may be an appropriate option for certain patients after multidisciplinary counseling. Alternatives to breastfeeding exist for patients who are unable to or do not desire to breastfeed.

Social Network Plasticity of Mice Parental Behavior

Neural plasticity occurs during developmental stages and is essential for sexual differentiation of the brain and the ensuing sex-dependent behavioral changes in adults. Maternal behavior is primarily affected by sex-related differences in the brain; however, chronic social isolation even in mature male mice can induce maternal retrieving and crouching behavior when they are first exposed to pups. Social milieus influence the inherent behavior of adults and alter the molecular architecture in the brain, thereby allowing higher levels of associated gene expression and molecular activity. This review explores the possibility that although the development of neural circuits is closely associated with maternal behavior, the brain can still retain its neuroplasticity in adults from a neuromolecular perspective. In addition, neuronal machinery such as neurotransmitters and neuropeptides might influence sociobehavioral changes. This review also discusses that the neural circuits regulating behaviors such as parenting and infanticide (including neglect behavior), might be controlled by neural relay on melanin concentrating hormone (MCH)–oxytocin in the hypothalamus during the positive and negative mode of action in maternal behavior. Furthermore, MCH–oxytocin neural relay might contribute to the anxiolytic effect on maternal behavior, which is involved with reward circuits.

Immunomodulatory Properties of Human Breast Milk: MicroRNA Contents and Potential Epigenetic Effects

Infants who are exclusively breastfed in the first six months of age receive adequate nutrients, achieving optimal immune protection and growth. In addition to the known nutritional components of human breast milk (HBM), i.e., water, carbohydrates, fats and proteins, it is also a rich source of microRNAs, which impact epigenetic mechanisms. This comprehensive work presents an up-to-date overview of the immunomodulatory constituents of HBM, highlighting its content of circulating microRNAs. The epigenetic effects of HBM are discussed, especially those regulated by miRNAs. HBM contains more than 1400 microRNAs. The majority of these microRNAs originate from the lactating gland and are based on the remodeling of cells in the gland during breastfeeding. These miRNAs can affect epigenetic patterns by several mechanisms, including DNA methylation, histone modifications and RNA regulation, which could ultimately result in alterations in gene expressions. Therefore, the unique microRNA profile of HBM, including exosomal microRNAs, is implicated in the regulation of the genes responsible for a variety of immunological and physiological functions, such as FTO, INS, IGF1, NRF2, GLUT1 and FOXP3 genes. Hence, studying the HBM miRNA composition is important for improving the nutritional approaches for pregnancy and infant's early life and preventing diseases that could occur in the future. Interestingly, the composition of miRNAs in HBM is affected by multiple factors, including diet, environmental and genetic factors.

Hybrid Broussonetia papyrifera Fermented Feed Can Play a Role Through Flavonoid Extracts to Increase Milk Production and Milk Fatty Acid Synthesis in Dairy Goats

In order to explore the effect of hybrid Broussonetia papyrifera fermented feed on milk production and milk quality of dairy goats, and to compare with alfalfa hay, three dairy goat diets were designed based on the principle of equal energy and equal protein. The goats in the control group were fed a basic TMR diet (CG group), and the other two groups were supplemented with 10% alfalfa hay (AH group) and 10% hybrid B. papyrifera fermented feed (BP group). The results showed that the dry matter intake and milk production of BP group increased significantly. The total amount of amino acids and the content of each amino acid in the milk of AH group and BP group were lower than those of CG group. The content of saturated fatty acids in the milk of BP group decreased while the content of unsaturated fatty acids increased. The contents of prolactin, estrogen and progesterone in BP goat serum were generally higher than those of AH goat and CG goat. Subsequently, this study separated and cultured mammary epithelial cells from breast tissue, and added flavone extracted from the leaves of hybrid B. papyrifera and alfalfa to their culture medium for comparison, which is one of their important bioactive components. The results showed that low-dose alfalfa flavone (AH) and hybrid B. papyrifera flavone (BP) can increase cell viability. They also can increase the accumulation of intracellular triglyceride and the formation of lipid droplets. Both AH flavone and BP flavone significantly up-regulated the expression of genes related to milk fat synthesis, including genes related to fatty acid de novo synthesis (ACACA, FASN, and SCD1), long-chain fatty acid activation and transport related genes (ACSL1), and genes related to transcription regulation (SREBP1). The three genes related to triglyceride synthesis (DGAT1, DGAT2, and GPAM) were all significantly increased by BP flavone. Both AH flavone and BP flavone significantly increased the protein expression of progesterone receptor and estrogen receptor in mammary epithelial cells but had no effect on prolactin receptor.

Estrogen receptor signaling mechanisms

The primary female sex hormones, estrogens, are responsible for the control of functions of the female reproductive system, as well as the development of secondary sexual characteristics that appear during puberty and sexual maturity. Estrogens exert their actions by binding to specific receptors, the estrogen receptors (ERs), which in turn activate transcriptional processes and/or signaling events that result in the control of gene expression. These actions can be mediated by direct binding of estrogen receptor complexes to specific sequences in gene promoters (genomic effects), or by mechanisms that do not involve direct binding to DNA (non-genomic effects). Whether acting via direct nuclear effects, indirect non-nuclear actions, or a combination of both, the effects of estrogens on gene expression are controlled by highly regulated complex mechanisms. In this chapter, we summarize the knowledge gained in the past 60years since the discovery of the estrogen receptors on the mechanisms governing estrogen-mediated gene expression. We provide an overview of estrogen biosynthesis, and we describe the main mechanisms by which the female sex hormone controls gene transcription in different tissues and cell types. Specifically, we address the molecular events governing regulation of gene expression via the nuclear estrogen receptors (ERα, and ERβ) and the membrane estrogen receptor (GPER1). We also describe mechanisms of cross-talk between signaling cascades activated by both nuclear and membrane estrogen receptors. Finally, we discuss natural compounds that are able to target specific estrogen receptors and their implications for human health and medical therapeutics.

The influence of time of birth and seasonal variations on weight loss in breastfeeding neonates

BACKGROUND

Breastfeeding (BF) neonates generally lose weight after birth. Neonatal factors like gestational age, birth weight and mode of delivery can affect the neonatal weight loss after birth. Similarly, maternal age, parity and illness may contribute to newborn weight loss. However, influence of the time of birth and season on changes in weight is not well elucidated.

OBJECTIVE

The aim of this study is to determine the effect of birth time and the seasonal variations on weight loss in BF newborns.

METHODS

In this retrospective study of a prospectively maintained database of two sets of groups, from January 2013 to October 2016, were evaluated- Birth time group and Seasonal group; Birth time of the groups was: night time 7pm to 7am and day time 7am to 7pm; and the seasonal variations groups studies were summer, fall, winter and spring. Weight loss of >5%, 7%, and 10% at <24 hours (h), 48 h and 72 h of birth, respectively, were considered as a significant weight loss. Preterm, exclusively formula fed and neonates admitted to NICU were excluded.

RESULTS

A total of 2044 newborns were analyzed. In the birth time group, babies born during the night time had significantly lost >5% of birth weight at <24 h (p < 0.01) and >7% birth weight at <48 h of life (p < 0.02). Weight loss >10% at <72 h was similar in both birth time cohorts. C-section, prolonged rupture of membrane, and maternal pre-delivery hospital stay for >12 h were significant contributing factors. Whereas, seasonal variations were not associated with weight loss in neonates.

CONCLUSION

BF babies born at night time lose significantly more weight during the first two days of life and seasonal association was not found to affect weight loss in the neonates.

Midfoot plantar pressure significantly increases during late gestation

BACKGROUND

A rise in plantar pressure has been observed in pregnant women with foot pain. The current literature on plantar pressure in pregnancy is sparse. It has been postulated that changes in plantar pressure result from the physiological effects of pregnancy. In this study we aim to quantify the plantar pressure of women in late pregnancy.

METHODS

Twenty-two pregnant women undergoing a caesarean section and twenty non-pregnant women were recruited from University Hospital Coventry and Warwickshire between May to June 2007. Plantar pressure measurements were performed using an in-shoe measurement system. The control group was compared with the pregnant group at 38 weeks gestation. A selection of the pregnant group had repeat measurements at 4 months post-partum. The pre and post-partum measurements were also compared.

RESULTS

The pregnant group (PG) exerted a significantly higher mean midfoot pressure compared to the non-pregnant control group (CG) (PG=115.5kPa, CG=95.4kPa; p=0.001). Post-partum (PP), there was a significant reduction in the mean and maximum midfoot pressure (mean; PG=111.9kPa, PP=66.2kPa; p<0.001, maximum; PG=184.0kPa, PP=108.3kPa; p<0.001).

CONCLUSIONS

The physiological changes in late pregnancy result in an increase in midfoot plantar pressure. This increase resolves post-partum.

Predictive factors for age at menopause in Caucasian females

OBJECTIVE

Early onset of menopause results in the premature exposure to low estrogen levels and is associated with a number of postmenopausal health problems and higher risk of mortality. The aim of this study was to determine genetic and environmental factors associated with age at natural and surgical menopause.

METHODS

Multiple regression analysis using a sample of Caucasians composed of 154 females with surgical and 248 with natural menopause.

RESULTS

Breastfeeding is a significant predictor of earlier natural menopause (P<0.05). Use of oral contraceptives and smoking were not significantly associated with age at menopause. Females who did not have history of pregnancies are at significantly higher risk (P<0.001) of getting early surgical menopause than those who did. We also tested the association of seven single nucleotide polymorphisms (SNPs) of the estrogen receptor alpha (ER-alpha) gene with age at menopause. No association was observed with age at menopause but the PvuII p allele was overrepresented in women with surgical menopause and associated with menopause per se (P=0.029; OR=1.8, 95% CI=1.1-3.0).

CONCLUSIONS

Breastfeeding and alcohol consumption are significantly associated with earlier natural menopause. No significant effects of the ER-alpha genotypes were observed on the age of menopause. Given the important role of the ER-alpha in estrogen signaling, which directly influences the menopausal process, further studies are required to better define the relationship between this gene and age at menopause.

Plasma thyrotropin-releasing hormone, prolactin, thyrotropin, and thyroxine concentrations following the intravenous or oral administration of thyrotropin-releasing hormone

In a further evaluation of the use of oral thyrotropin-releasing hormone (TRH) in puerperally lactating women, a radioimmunoassay for its measurement has been developed. Its concentration in plasma as well as that of prolactin (PRL), thyrotropin (TSH) and thyroxine (T4) were measured following either intravenous or oral administration of TRH. Basal concentrations of TRH in 14 normally cycling women ranged from less than 5 to 17 pg/ml. Two luteal phase studies produced peaks in plasma TRH 5 to 10 minutes after 100 micrograms of TRH administered intravenously with a return to basal concentrations within 2 to 3 hours. In 10 normally menstruating women, ingestion of 10 mg of TRH orally resulted in plasma TRH which peaked at 423 +/- 123 pg/ml (standard error of the mean) at 30-minutes. Plasma PRL, TSH, and T4 also increased and remained slightly elevated at 4 hours. These 8-hour studies were performed in a puerperal lactating woman who had ingested 10 mg of TRH orally twice a day for 7 days prior to blood sampling. TRH concentrations declined throughout each day while TSH rose slightly in the first 1 to 2 hours but remained within normal limits. The prolonged administration of 10 mg of TRH orally twice daily to three puerperally lactating women resulted in elevations in plasma TRH 2 to 3 hours following hormone administration, yet no significant increases in plasma TSH were observed. Both endogenous TRH and TSH were measured before and after 22 nursing events in nine puerperally lactating women. There was no change in the concentration of either substance and all values were similar to those obtained in normally menstruating women.