Drospirenone increases central and peripheral β-endorphin in ovariectomized female rats

Hormonal contraceptive exposure relates to changes in resting state functional connectivity of anterior cingulate cortex and amygdala

Introduction

Hormonal contraceptives (HCs), nowadays one of the most used contraceptive methods, downregulate endogenous ovarian hormones, which have multiple plastic effects in the adult brain. HCs usually contain a synthetic estrogen, ethinyl-estradiol, and a synthetic progestin, which can be classified as androgenic or anti-androgenic, depending on their interaction with androgen receptors. Both the anterior cingulate cortex (ACC) and the amygdala express steroid receptors and have shown differential functionality depending on the hormonal status of the participant and the use of HC. In this work, we investigated for the first time the relationship between ACC and amygdala resting state functional connectivity (rs-FC) and HC use duration, while controlling for progestin androgenicity.

Methods

A total of 231 healthy young women participated in five different magnetic resonance imaging studies and were included in the final analysis. The relation between HC use duration and (i) gray matter volume, (ii) fractional amplitude of low-frequency fluctuations, and (iii) seed-based connectivity during resting state in the amygdalae and ACC was investigated in this large sample of women.

Results

In general, rs-FC of the amygdalae with frontal areas, and between the ACC and temporoparietal areas, decreased the longer the HC exposure and independently of the progestin's androgenicity. The type of HC's progestin did show a differential effect in the gray matter volume of left ACC and the connectivity between bilateral ACC and the right inferior frontal gyrus.

Progesterone and contraceptive progestin actions on the brain: A systematic review of animal studies and comparison to human neuroimaging studies

In this review we systematically summarize the effects of progesterone and synthetic progestins on neurogenesis, synaptogenesis, myelination and six neurotransmitter systems. Several parallels between progesterone and older generation progestin actions emerged, suggesting actions via progesterone receptors. However, existing results suggest a general lack of knowledge regarding the effects of currently used progestins in hormonal contraception regarding these cellular and molecular brain parameters. Human neuroimaging studies were reviewed with a focus on randomized placebo-controlled trials and cross-sectional studies controlling for progestin type. The prefrontal cortex, amygdala, salience network and hippocampus were identified as regions of interest for future preclinical studies. This review proposes a series of experiments to elucidate the cellular and molecular actions of contraceptive progestins in these areas and link these actions to behavioral markers of emotional and cognitive functioning. Emotional effects of contraceptive progestins appear to be related to 1) alterations in the serotonergic system, 2) direct/indirect modulations of inhibitory GABA-ergic signalling via effects on the allopregnanolone content of the brain, which differ between androgenic and anti-androgenic progestins. Cognitive effects of combined oral contraceptives appear to depend on the ethinylestradiol dose.

Mood disorders and hormonal status across women's life: a narrative review

Depressive disorders and anxiety states represent one of the most frequent psychiatric pathologies occurring transiently in vulnerable women throughout their life, from puberty to menopause. It is now known that sex hormones play a key role on the nervous system, interfering with neuronal plasticity and enhancing the processes of learning, memory, cognition, and mood. Numerous mechanisms are at the base of these processes, displaying interactions between estrogen and serotoninergic, dopaminergic, and GABAergic receptors at the central level. Therefore, given the sexual steroids fluctuations throughout the entire female lifespan, and considering the role played by sex hormones at the central level, it is not surprising to observe the onset of mood or neurodegenerative disorders over time. This is especially true for women in hormonal transition phase, such as puberty, postpartum and the menopausal transition. Moreover, all these conditions are characterized by hormone withdrawal, imbalance, or modifications due to menopausal hormone therapies or contraceptives which could prompt to a deterioration of mood and cognition impairment or to an improvement in the quality of life. More studies are needed to better understand the hormone-related effects on the nervous system, and the underlying pathways involved in transitional or chronic mood disorders, to promote new patient-specific therapeutic strategies more effective than the current ones and tailored according to the individual need and women's life period.

What is there to know about the effects of progestins on the human brain and cognition?

Progestins are an important component of hormonal contraceptives (HCs) and hormone replacement therapies (HRTs). Despite an increasing number of studies elucidating the effects of HCs and HRTs, little is known about the effects of different types of progestins included in these medications on the brain. Animal studies suggest that various progestins interact differently with sex steroid, mineralocorticoid and glucocorticoid receptors and have specific modulatory effects on neurotransmitter systems and on the expression of neuropeptides, suggesting differential impacts on cognition and behavior. This review focuses on the currently available knowledge from human behavioral and neuroimaging studies pooled with evidence from animal research regarding the effects of progestins on the brain. The reviewed information is highly relevant for improving women's mental health and making informed choices regarding specific types of contraception or treatment.

Modeling hormonal contraception in female rats: A framework for studies in behavioral neurobiology

Research on hormonal contraceptives (HC) in animal models is lacking, and as a result, so is our understanding of the impact of HC on the brain and behavior. Here, we provide a review of the pharmacology of HC, as well as the methodology and best practices for designing a model of HC in female rats. We outline specific methodological considerations regarding dosing, route of administration, exposure time/timing, and selecting a control group. We also provide a framework outlining important levels of analysis for thinking about the impact of HC on behavioral and neurobiological outcomes. The purpose of this review is to equip researchers with foundational knowledge, and some basic elements of experimental design for future studies investigating the impact of HC on the brain and behavior of female rats.

Hormonal Contraception and Depression: Updated Evidence and Implications in Clinical Practice

Hormonal contraceptives are used worldwide by more than 100 million women. Some studies have been published about the possible appearance of depressive symptoms when using hormonal contraceptives, but this link is still a matter of debate. The purpose of this review is to provide an update of the literature on this issue, and to investigate the possible explanations of this problem based on animal and human studies. The main pathway responsible for menstrual cycle-related mood changes is the γ-aminobutyric acid pathway, which is sensitive to changes in the levels of progesterone and of its metabolites, the neurosteroids. In particular, allopregnanolone is a potentiating neurosteroid with anxiolytic and anti-convulsant effects whose levels change during a normal menstrual cycle together with progesterone levels. Progestins have different effects on allopregnanolone, mainly owing to their diverse androgenicity. Moreover, they might affect brain structure and function, even though the meaning of these changes has yet to be clarified. It is important to define the groups of women in which negative mood disorders are more likely to occur. Adolescence is a critical period and this age-specific vulnerability is complex and likely bidirectional. Moreover, women with a history of mood affective disorders or premenstrual dysphoric syndrome are at a higher risk when taking contraceptives. In this review, we aim to provide clinicians with advice on how to approach these difficult situations.

Progress in progestin-based therapies for neurological disorders

Hormone therapy, primarily progesterone and progestins, for central nervous system (CNS) disorders represents an emerging field of regenerative medicine. Following a failed clinical trial of progesterone for traumatic brain injury treatment, attention has shifted to the progestin Nestorone for its ability to potently and selectively transactivate progesterone receptors at relatively low doses, resulting in robust neurogenetic, remyelinating, and anti-inflammatory effects. That CNS disorders, including multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), spinal cord injury (SCI), and stroke, develop via demyelinating, cell death, and/or inflammatory pathological pathways advances Nestorone as an auspicious candidate for these disorders. Here, we assess the scientific and clinical progress over decades of research into progesterone, progestins, and Nestorone as neuroprotective agents in MS, ALS, SCI, and stroke. We also offer recommendations for optimizing timing, dosage, and route of the drug regimen, and identifying candidate patient populations, in advancing Nestorone to the clinic.

The other side of progestins: effects in the brain

Progestins are a broad class of progestational agents widely differing in their chemical structures and pharmacological properties. Despite emerging data suggest that progestins, besides their action as endometrial protection, can also have multiple nonreproductive functions, much remains to be discovered regarding the actions exerted by these molecules in the nervous system. Here, we report the role exerted by different progestins, currently used for contraception or in postmenopausal hormone replacement therapies, in regulating cognitive functions as well as social behavior and mood. We provide evidence that the effects and mechanisms underlying their actions are still confusing due to the use of different estrogens and progestins as well as different doses, duration of exposure, route of administration, baseline hormonal status and age of treated women. We also discuss the emerging issue concerning the relevant increase of these substances in the environment, able to deeply affect aquatic wildlife as well as to exert a possible influence in humans, which may be exposed to these compounds via contaminated drinking water and seafood. Finally, we report literature data showing the neurobiological action of progestins and in particular their importance during neurodegenerative events. This is extremely interesting, since some of the progestins currently used in clinical practice exert neuroprotective and anti-inflammatory effects in the nervous system, opening new promising opportunities for the use of these molecules as therapeutic agents for trauma and neurodegenerative disorders.

Advances in neurosteroids: role in clinical practice

The steroidogenic endocrine glands and local synthesis both contribute to the pool of steroids present in the central nervous system and peripheral nervous system. Although the synthesis of neurosteroids in the nervous system is now well established, the spectrum of respective functions in regulating neuronal and glial functions remains to be fully elucidated. From the concept of neurosteroids derives another treatment strategy: the use of pharmaceutical agents that increase the synthesis of endogenous neurosteroids within the nervous system. This approach has so far been hampered by lack of knowledge concerning the regulation of the biosynthetic pathways of neurosteroids and their relationship with sex steroids produced by the peripheral gland or with exogenous steroids. The present review summarizes some of the available clinical and experimental findings supporting the critical role of neurosteroids during fertile life and reproductive aging and their relationship with endogenous and exogenous sex steroids. The brain metabolism of synthetic progestins and the implications of DHEA treatment in postmenopausal women will also be discussed.

Preclinical pharmacological profile of nomegestrol acetate, a synthetic 19-nor-progesterone derivative

BACKGROUND

Nomegestrol acetate (NOMAC), a synthetic progestogen derived from 19-nor-progesterone, recently completed clinical trials for use with 17beta-estradiol in a new monophasic combined oral contraceptive. In this review, published as well as previously unpublished preclinical studies that detail the effects of NOMAC on estrogenic, progestogenic, and androgenic systems, as well as mineralocorticoid, glucocorticoid, bone, and metabolic indices are described.

METHODS

In vitro assays to determine NOMAC structure-activity relationships used tissue derived from rat uteri. Transactivation profiles were performed using Chinese hamster ovary (CHO) cells transfected with cDNAs encoding human steroid receptors. Estrogenic and anti-estrogenic activities were monitored in vivo in rats as well as in vitro in human breast cancer cells. Standard in vivo techniques were used in rats to determine progestational activity; antigonadotropic, androgenic, mineralocorticoid, and glucocorticoid activities; as well as effects on bone and other metabolic indices. Ovulation inhibition was monitored in rats and primates. NOMAC's effects on cardiovascular systems were determined in dogs and primates.

RESULTS

NOMAC was without significant agonistic or antagonistic activity for estrogen receptor alpha or beta in vitro, and inhibited ovulation in rats and monkeys (2.5 mg/kg and 1 mg/kg, respectively). NOMAC lacked androgenic, antimineralocorticoid, glucocorticoid, and metabolic activity and exhibited moderate anti-androgenic activity in rats. NOMAC did not affect bone mineral density (BMD) in rats or hemodynamic and electrophysiologic parameters in dogs and primates.

CONCLUSIONS

NOMAC is a selective progestogen structurally similar to progesterone that has modest anti-androgenic activity and does not affect lipid or carbohydrate metabolism, BMD, or many cardiovascular parameters in selected animal models.

Beyaz®: An Oral Contraceptive Fortified with Folate

Beyaz® (Bayer Healthcare Pharmaceuticals, Berlin, Germany) consists of 28 film-coated tablets: 24 tablets each containing 3 mg drospirenone plus 20 µg ethinylestradiol (EE) and 451 µg levomefolate calcium followed by four tablets, each containing 451 µg levomefolate calcium. It has the same indications of the parent compound 20 µg EE/3 mg drospirenone in a 24/4-day regimen (i.e., contraception, moderate acne, premenstrual dysforic disorder). In addition, the 24-day regimen with 20 µg EE/3 mg drospirenone/levomefolate calcium assure significant increases in red blood cell and plasma folate levels reaching values indicated to be protective in reducing the risk of neural tube defects. A progressive decrease in folate levels has been observed in women taking a 30 µg EE pill fortified with the same dose of levomefolate calcium upon discontinuation. At 4 and 8 weeks following cessation of the oral contraceptive, red blood cell folate levels >906 nmol/l were measured in 85 and 60% of women respectively. Because of this, the folate-containing pill may aid in reducing the risk of neural tube defects in a pregnancy conceived during use or shortly after the discontinuation of the product.

Neurosteroids in clinical practice: implications for women’s health

The steroidogenic endocrine glands and local synthesis both contribute to the pool of steroids present in the central nervous system (CNS) and peripheral nervous system (PNS). Although the synthesis of neurosteroids in the nervous system is now well established, the spectrum of respective functions in regulating neuronal and glial functions remains to be fully elucidated. From the concept of neurosteroids derives another therapeutical strategy: the use of pharmaceutical agents that increase the synthesis of endogenous neurosteroids within the nervous system. This approach is so far hampered by the lack of knowledge concerning the regulation of the biosynthetic pathways of neurosteroids and their relationship with sex steroids produced by peripheral glands. The present review summarizes some of the available clinical and experimental findings supporting the critical role of neuro-steroids during the fertile life and reproductive aging and their relationship with endogenous and exogenous sex steroids. Brain metabolism of synthethic progestins and the implication of dehydroepiandrosterone (DHEA) treatment in post-menopausal women will be also discussed.

Central modifications of allopregnanolone and beta-endorphin following subcutaneous administration of Nestorone

The aim of the present study was to evaluate the potential action of Nestorone (alone or in combination with estradiol valerate) on the level of allopregnanolone and of the opioid beta-endorphin in selected brain areas. Wistar ovariectomized rats were given 0.05 mg/(kg day) of estradiol valerate (E2V) or subcutaneous Nestorone at three dose levels: low dose (10 microg/(kg day)), antiovulatory dose (50 micro/(kg day)) and high dose (250 microg/(kg day)) with and without E2V. E2V therapy reversed the reduction of allopregnanolone and beta-endorphin induced by ovariectomy anywhere was analyzed except for the adrenal gland. Nestorone showed no effect on allopregnanolone concentration in serum or any part of the brain tissue when given alone while it had a synergistic increasing effect in allopregnanolone concentration in some parts of the brain (hippocampus, hypothalamus, anterior pituitary and serum) when given at high dose of 250 microg/(kg day) in combination with E2V. At lower doses it possesses a synergistic effect with E2V only in the hippocampus (at 50 microg/(kg day)) and in the anterior pituitary (at 10 and 50 microg/(kg day)). Nestorone administered alone at any dose led to significant increase in beta-endorphin levels in the hippocampus only while, in the high dose group, there was a significant increase in endorphin levels in anterior pituitary and hypothalamus in addition to hippocampus as compared to ovariectomized control rats. In addition, only the highest dose of Nestorone added to estrogen increased beta-endorphin levels of hippocampus and plasma. Thus the lower doses of Nestorone alone or in combination with estrogen do not seem to exert any great effect on both allopregnanolone and beta-endorphin. It is only the highest dose of Nestorone that increases allopregnanolone and beta-endorphin levels in selected brain areas, which are the hippocampus, the hypothalamus, the anterior pituitary and serum/plasma. This suggests that Nestorone at the antiovulatory dose levels may not alter the positive effects of estrogen treatment on mood and behaviour.

Progestogens and brain: an update

Each synthetic progestins has its own specific activities on different tissues, which can vary significantly between progestins of different classes and even within the same class. Indeed, different progestins may support or oppose the effects of estrogen depending on the tissue, thereby supporting the concept that the clinical selection of progestins for HRT is critical in determining potential positive or detrimental effects. These actions might be particularly relevant in the central nervous system (CNS) where progesterone (P) has pivotal roles besides reproduction and sexual behavior, going from neuropsychological effects to neuroprotective functions. Growing evidence supports the idea that synthetic progestins differ significantly in their brain effects, and clinical studies indicate that these differences also occur in women. Molecular and cellular characterization of the signaling properties of synthetic progestins in brain cells is therefore required and is hoped will lead to a better clinical utilization of the available compounds, as well as to new concepts in the engineering of new molecules. The aim of the present paper is to briefly review and compare neuroendocrine effects of progestogens with special reference to P metabolism into neuroactive steroids and the opioids system.

Endogenous opiates and behavior: 2007

This paper is the thirtieth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2007 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.

Effects of nomegestrol acetate administration on central and peripheral beta-endorphin and allopregnanolone in ovx rats

The aim of this study was to investigate the effects of nomegestrol acetate (NOMAc) on the central nervous system by analyzing the neurosteroid allopregnanolone and the opioid beta-endorphin (beta-endorphin). 104 Wistar female rats were used in this study; one group of fertile and one group of ovariectomized rats were used as control. The others were ovariectomized and they underwent a 2-week oral treatment of NOMAc (0.05, 0.1, 0.2, 0.5, 1mg/kg/day), alone or with 0.05 mg/kg/day of estradiol valerate (E2V). Allopregnanolone and beta-endorphin were assessed in different brain areas and in circulation. Ovariectomy decreased allopregnanolone anywhere except in the adrenal gland and E2V reversed the effects of ovariectomy. 0.5 and 1mg/kg/day of NOMAc increased allopregnanolone levels in hippocampus. Combined administration of 1mg/kg/day of NOMAc plus E2V induced a further increase of allopregnanolone levels in hippocampus, hypothalamus, and anterior pituitary. NOMAc (1mg/kg/day) decreased the adrenal content of allopregnanolone, both by itself and associated with E2V. NOMAc increased hippocampal and hypothalamic content of beta-endorphin at the highest doses, and it increased positively E2V action, at 1mg/kg/day, also in anterior pituitary and plasma. These findings reinforce the clinical data regarding the capability of NOMAc to modulate the pathways involved in mood and behaviour. In fact, due to the NOMAc action on hippocampus, hypothalamus, and anterior pituitary, our results highlight the selectivity of NOMAc on part of the limbic system and the anterior pituitary, regarding both allopregnanolone and beta-endorphin.

Dydrogesterone increases allopregnanolone in selected brain areas and in serum of female rats

OBJECTIVE

To investigate the effects of dydrogesterone (DYD), a synthetic progestin largely used in hormone therapy, on the central nervous system by studying two markers of the neuroendocrine function: the neurosteroid allopregnanolone and the opioid beta-endorphin.

DESIGN

Experimental study on animal model.

SETTING

Academic research environment.

ANIMAL(S)

72 Wistar female rats.

INTERVENTION(S)

One group of fertile and one of ovariectomized rats (receiving placebo) were used as control. After ovariectomy, the rats underwent a 2-week oral treatment of DYD (0.2, 0.6, or 1.0 mg/kg per day), alone or with estradiol valerate (E2V; 0.05 mg/kg per day).

MAIN OUTCOME MEASURE(S)

Allopregnanolone and beta-endorphin, assessed in different brain areas and in circulation.

RESULT(S)

Ovariectomy decreased allopregnanolone anywhere except in the adrenal gland and reduced beta-endorphin central levels; E2V reversed the effects of ovariectomy; and DYD (1 mg/kg per day) increased allopregnanolone levels in frontal lobe, hippocampus, and hypothalamus. Combined administration of DYD at 1 mg/kg per day plus E2V determined a further increase of allopregnanolone levels in frontal lobe, hippocampus, hypothalamus, and serum. Dydrogesterone did not modify the levels of beta-endorphin induced by E2V.

CONCLUSION(S)

Dydrogesterone interacts with allopregnanolone levels (less with beta-endorphin), and it can be considered important modulator of the neuroendocrine function.

Progesterone and progestins: effects on brain, allopregnanolone and beta-endorphin

The increased use of hormonal therapies over the last years has led to improve the knowledge of pharmacological, biochemical and metabolic properties of several progestins and their effects in target tissues, such as the central nervous system. Progesterone and synthetic progestational agents are able to modulate the synthesis and release of several neurotransmitters and neuropeptides in response to specific physiological and pathological stimuli. While these actions may relay on differential activation of progesterone receptor or recruitment of intracellular pathways, some of the differences found between synthetic progestins may depend on the specific conversion to neuroactive steroids, such as the 3-alpha, 5-alpha reduced metabolite, allopregnanolone. This is a potent endogenous steroid that rapidly affects the excitability of neurons and glia cells through direct modulation of the GABA-A receptors activity exerting hypnotic/sedative, anxiolytic, anaesthetic and anticonvulsive properties. Estrogens increase the CNS and serum levels of allopregnanolone and the addition of certain but not all synthetic progestins determines a further increase in allopregnanolone levels, suggesting that the metabolism into this reduced product is related to the chemical structure of progestin molecule used. In addition, depending on specific progestin molecule used, different interaction are found with the estradiol-induced beta-endorphin synthesis and release, showing that diverse progestins have specific and divergent actions on the opiatergic system. These results highlight the concept that natural and synthetic progesterone receptor agonists may systematically induce different biological actions in CNS. This may have far-reaching implications for the clinical effects and related indications of each compound.