Cardiovascular effects of medroxyprogesterone acetate and progesterone: a case of mistaken identity?

Sex Chromosomes and Sex Hormones: Dissecting the Forces That Differentiate Female and Male Hearts

The heart is a highly sex-biased organ, as sex shapes innumerable aspects of heart health and disease. Sex chromosomes and sex hormones -testosterone, progesterone, and estrogen- establish and perpetuate the division between male and female myocardium. Of these differentiating factors, the insulating effects of estrogen have been rigorously interrogated and reviewed, whereas the influence of sex chromosomes, testosterone, and progesterone remains in dispute or ill-defined. Here, we synthesize growing evidence that sex chromosomes and sex hormones substantially bias heart form, function, and dysfunction in a context-dependent fashion. The discrete protective functions ascribed to each of the 3 estrogen receptors are also enumerated. Subsequently, we overview obstacles that have historically discouraged the inclusion of female subjects in basic science such as the impact of the female estrus cycle and reproductive senescence on data reliability and reproducibility. Furthermore, we weigh the utility of several common strategies to intercept and rescue sex-specific protection. Last, we warn of common compounds in animal chow and cell culture that interfere with estrogen signaling. In sum, we survey the controversies and challenges that stem from sex-inclusive cardiovascular research, comparing the possible causes of cardiac sex bias, elucidating sex chromosome or hormone-dependent processes in the heart, describing common lapses that imperil female and male cell and animal work, and illuminating facets of the female heart yet unexplored or still uncertain.

A comprehensive review on the effects of sex hormones on chemotherapy-induced cardiotoxicity: are they lucrative or unprofitable?

Chemotherapy is one of the routine treatment for preventing rapid growth of the tumor cells. However, chemotherapeutic agents, especially doxorubicin cause damages to the normal cells especially cardiomyocytes. Cardiotoxicity induced by chemotherapeutic drugs lead to the myocardial cell injury and finally causes left ventricular dysfunction. It seems that there were some differences in the severity of cardiovascular side effects of drugs used in the treatment of cancers. Sex hormones in male and female play crucial roles in cardiovascular development and physiological function of the heart and blood vessels. Gender differences and sex-specific hormones influence various aspects of cardiovascular health, including ventricular function, mitochondrial autophagy, and the development of abdominal aortic aneurysms. The most important gender related hormones are LH, FSH, testosterone, estrogen, progesterone, prolactin and oxytocin. They exert very important cardiovascular effects via different signaling mechanisms. Sex related hormones are also important in the cardiovascular side effects of chemotherapeutic agents, so that chronic cardiotoxicity induced by anthracyclines is more common in women. During different stages of life (before, during, and after sexual life), the levels of these hormones will be changed. This alterations can affect cardiovascular function during physiological conditions and pathological process. Because of the importance of the sex related hormones in the cardiac function, in this review we tried to comprehensively elucidate the role of these physiological hormones in cardiotoxicity induced by chemotherapeutic agents with emphasizing their signaling mechanisms.

Transformation or replacement - Effects of hormone therapy on cardiovascular risk

Hormone therapy (HT) is important and frequently used both regarding replacement therapy (HRT) and gender affirming therapy (GAHT). While HRT has been effective in addressing symptoms related to hormone shortage, several side effects have been described. In this context, there are some studies that show increased cardiovascular risk. However, there are also studies reporting protective aspects of HT. Nevertheless, the exact impact of HT on cardiovascular risk and the underlying mechanisms remain poorly understood. This article explores the relationship between diverse types of HT and cardiovascular risk, focusing on mechanistic insights of the underlying hormones on platelet and leukocyte function as well as on effects on endothelial and adipose tissue cells.

Change of HeART: Cardiovascular Implications of Assisted Reproductive Technology

Cardiovascular (CV) disease is the leading cause of death in women, and it may manifest differently than in men, in part related to sex-specific CV risk factors. In females, assisted reproductive technologies (ARTs) are commonly used to treat infertility, and they utilize controlled ovarian stimulation involving the administration of exogenous sex hormones. ARTs, and especially controlled ovarian stimulation, have been associated with an increased pregnancy and short-term CV risk, although the long-term CV implications of these treatments in individuals treated with ARTs and their offspring remain unclear. This review endeavors to provide a comprehensive examination of what is known about the relationship between ART and CV outcomes for females treated with ARTs, as well as their offspring, and recommendations for future research. Novel insights into female-specific CV risk factors are critical to reduce the disproportionate burden of CV disease in Canadian women. ART has revolutionized reproductive medicine, offering hope to millions of individuals with infertility worldwide, and a further understanding of the CV implications of this important sex-specific CV risk factor is warranted urgently.

Injectable Contraceptive, Depo-Provera, Produces Erratic Beating Patterns in Patient-Specific Induced Pluripotent Stem Cell-derived Cardiomyocytes with Type 2 Long QT Syndrome

BACKGROUND

Long QT syndrome type 2 (LQT2) is caused by pathogenic variants in KCNH2. LQT2 may manifest as QT prolongation on an ECG and present with arrhythmic syncope/seizures, sudden cardiac arrest/death. Oral progestin-based contraceptives may increase the risk of LQT2-triggered cardiac events in women. We previously reported on a LQT2 woman with recurrent cardiac events temporally related and attributed to the progestin-based contraceptive, medroxyprogesterone acetate ("Depo-Provera", Depo).

OBJECTIVE

To evaluate the arrhythmic-risk of Depo in a patient-specific induced pluripotent stem cell-derived cardiomyocyte (iPSC-CM) model of LQT2.

METHODS

An iPSC-CM line was generated from a 40-year-old female with p.G1006Afs*49-KCNH2. A CRISPR/Cas9 gene-edited/variant-corrected, isogenic control (IC) iPSC-CM line was generated. FluoVolt was used to measure the action potential duration (APD) following treatment with 10 μM Depo. Erratic beating patterns characterized as alternating spike amplitudes, alternans, or early after depolarization-like phenomena were assessed using multi-electrode array (MEA) following 10 μM Depo, 1 μM isoproterenol (ISO), or combined Depo + ISO treatment.

RESULTS

Depo treatment shortened the APD-90 of the G1006Afs*49 iPSC-CMs from 394±10 ms to 303±10 ms (p<0.0001). Combined Depo and ISO treatment increased the percent of electrodes displaying erratic beating in G1006Afs*49 iPSC-CMs [baseline 18±5% vs. Depo + ISO 54±5% (p<0.0001)] but not in IC iPSC-CMs [baseline 0±0% vs. Depo + ISO 10±3% (p=0.9659)].

CONCLUSION

This cell study provides a potential mechanism for the patient's clinically documented Depo-associated episodes of recurrent ventricular fibrillation. This in-vitro data should prompt a large-scale clinical assessment of Depo's potential pro-arrhythmic effect in women with LQT2.

PGRMC1 Ablation Protects from Energy-Starved Heart Failure by Promoting Fatty Acid/Pyruvate Oxidation

Heart failure (HF) is an emerging epidemic with a high mortality rate. Apart from conventional treatment methods, such as surgery or use of vasodilation drugs, metabolic therapy has been suggested as a new therapeutic strategy. The heart relies on fatty acid oxidation and glucose (pyruvate) oxidation for ATP-mediated contractility; the former meets most of the energy requirement, but the latter is more efficient. Inhibition of fatty acid oxidation leads to the induction of pyruvate oxidation and provides cardioprotection to failing energy-starved hearts. One of the non-canonical types of sex hormone receptors, progesterone receptor membrane component 1 (Pgrmc1), is a non-genomic progesterone receptor associated with reproduction and fertility. Recent studies revealed that Pgrmc1 regulates glucose and fatty acid synthesis. Notably, Pgrmc1 has also been associated with diabetic cardiomyopathy, as it reduces lipid-mediated toxicity and delays cardiac injury. However, the mechanism by which Pgrmc1 influences the energy-starved failing heart remains unknown. In this study, we found that loss of Pgrmc1 inhibited glycolysis and increased fatty acid/pyruvate oxidation, which is directly associated with ATP production, in starved hearts. Loss of Pgrmc1 during starvation activated the phosphorylation of AMP-activated protein kinase, which induced cardiac ATP production. Pgrmc1 loss increased the cellular respiration of cardiomyocytes under low-glucose conditions. In isoproterenol-induced cardiac injury, Pgrmc1 knockout resulted in less fibrosis and low heart failure marker expression. In summary, our results revealed that Pgrmc1 ablation in energy-deficit conditions increases fatty acid/pyruvate oxidation to protect against cardiac damage via energy starvation. Moreover, Pgrmc1 may be a regulator of cardiac metabolism that switches the dominance of glucose-fatty acid usage according to nutritional status and nutrient availability in the heart.

[Menopausal hormone therapy: internal-endocrine point of view]

The history of menopausal hormone therapy (MHT) started in 1942 in the US and became very popular in the 1960s worldwide because of the beneficial effects on vasomotor-vegetative and vulvovaginal symptoms. These symptoms may begin already in the premenopausal period, and can last for more than 10 years with reduced quality of life. Many women with vasomotor-vegetative symptoms do not visit a gynaecologist first but primarily a general physician or cardiologist because of instable blood pressure and palpitations, leading to the focus on the heart. To avoid unnecessary examinations and treatment with ß-blockers or antidepressants, an interdisciplinary look is necessary. In most cases, appropriate and low dose hormone replacement will relieve the symptoms and restore quality of life. In addition, it is worthwhile to know about the long-term effect of hormone deficiency as well as replacement on the different organ systems and the possible influences of hormone replacement therapy including contra indications. This is especially necessary after the uncertainties raised after the first deleterious announcements of the currently corrected results of the WHI (women's health initiative) study.

Additive effects of low concentrations of estradiol-17β and progesterone on nitric oxide production by human vascular endothelial cells through shared signaling pathways

Potential cardiovascular benefits of low-dose formulations of estrogens and progesterone (P4) for treating climacteric symptoms in postmenopausal women remain unclear because information is lacking on their combined vascular effects. Protective effects of low concentrations (5nM) of P4 and estradiol-17β (E2), alone and in combination (P4+E2), were investigated in a nongenomic model of vascular protection which measured acute increases in nitric oxide (NO) production by cultured human umbilical vein endothelial cells (HUVECs). Treatment with 5nM P4+E2 for twenty minutes significantly increased NO production and endothelial NO synthase (eNOS) phosphorylation, whereas 5nM treatments with either steroid alone were ineffective. The 5nM P4+E2 treatment also increased phosphorylation of ERK and Akt, mimicking the effects of higher concentrations of P4 and E2 alone. Pre-treatment with inhibitors of PI3K (wortmannin), Akt (ML-9), and MAP kinase (AZD6244 and U0126) completely blocked the NO response to 5nM P4+E2. Combined 5nM treatments with specific estrogen and progesterone receptor agonists showed an involvement of membrane progesterone receptor alpha (mPRα, also known as PAQR7), G protein-coupled estrogen receptor 1 (GPER), and estrogen receptor alpha (ERα), but not ERβ, in P4+E2 stimulation of NO production. P4+E2 also exerted genomic actions, increasing mPRα, GPER, cyclooxygenase-1, and prostacyclin-synthase mRNA levels. Taken together, the results show that a low concentration of P4+E2 rapidly increases NO production in HUVECs through mPRα, ERα, and GPER and involves common signaling pathways, PI3K/Akt and MAP kinase. These in vitro findings suggest that low doses of E2 and P4 may also have some beneficial cardiovascular effects in vivo when administered as hormone replacement therapy (HRT) for post-menopausal women.

Progesterone increases nitric oxide synthesis in human vascular endothelial cells through activation of membrane progesterone receptor-α

Progesterone exerts beneficial effects on the human cardiovascular system by inducing rapid increases in nitric oxide (NO) production in vascular endothelial cells, but the receptors mediating these nongenomic progesterone actions remain unclear. Using human umbilical vein endothelial cells (HUVECs) as a model, we show that progesterone binds to plasma membranes of HUVECs with the characteristics of membrane progesterone receptors (mPRs). The selective mPR agonist Org OD 02-0 had high binding affinity for the progesterone receptor on HUVEC membranes, whereas nuclear PR (nPR) agonists R5020 and medroxyprogesterone acetate displayed low binding affinities. Immunocytochemical and Western blot analyses confirmed that mPRs are expressed in HUVECs and are localized on their plasma membranes. NO levels increased rapidly after treatment with 20 nM progesterone, Org OD 02-0, and a progesterone-BSA conjugate but not with R5020, suggesting that this progesterone action is at the cell surface and initiated through mPRs. Progesterone and Org OD 02-0 (20 nM) also significantly increased endothelial nitric oxide synthase (eNOS) activity and eNOS phosphorylation. Knockdown of mPRα expression by treatment with small-interfering RNA (siRNA) blocked the stimulatory effects of 20 nM progesterone on NO production and eNOS phosphorylation, whereas knockdown of nPR was ineffective. Treatment with PI3K/Akt and MAP kinase inhibitors blocked the stimulatory effects of progesterone, Org OD 02-0, and progesterone-BSA on NO production and eNOS phosphorylation and also prevented progesterone- and Org OD 02-0-induced increases in Akt and ERK phosphorylation. The results suggest that progesterone stimulation of NO production in HUVECs is mediated by mPRα and involves signaling through PI3K/Akt and MAP kinase pathways.

Long QTc Syndrome Type 2 Presenting in a Postpartum Patient on Medroxyprogesterone

Introduction. Congenital long QT syndrome type 2 (LQTS2) is a rare inherited cardiac abnormality resulting in increased risk of polymorphic ventricular tachycardia (PVT). Case Description. A 21-year-old postpartum female presented with syncopal episode after phone alarm. She was noted to have PVT on telemetry monitoring in the emergency department. EKG revealed QTc of 530. The patient's only medication was medroxyprogesterone. She ultimately received a dual chamber pacemaker with ICD. Discussion. LQTS2 is associated with alarm sounds as a precipitating factor. Postpartum hormonal shifts as well as medroxyprogesterone have significant effect on native QTc duration.

Medroxyprogesterone acetate enhances monocyte-endothelial interaction under flow conditions by stimulating the expression of cell adhesion molecules

CONTEXT

Monocyte adhesion to endothelial cells is an important initial event in atherosclerosis and is partially mediated by adhesion molecule expression on the cell surface. Although estrogens inhibit atherosclerosis development, effects of coadministered progestogen remain controversial.

OBJECTIVE

We examined the effects of progestogen on cytokine-stimulated human umbilical venous endothelial cell (HUVEC) expression of adhesion molecules.

DESIGN

In HUVECs, adhesion molecule mRNA levels were measured by real-time PCR. Protein expression was quantified by immunocytochemistry and ELISAs. To mimic the monocyte adherence to endothelial cells, we used a flow chamber system to assess progestogen effects on U937 monocytoid cell adherence to HUVEC monolayers. We also examined the suppression effects of adhesion molecules with small interference RNAs.

RESULTS

mRNA levels of adhesion molecules in HUVECs treated with medroxyprogesterone acetate (MPA) or 17β-estradiol + MPA were 1.7- to 2.5-fold higher than those in the control. MPA increased the protein expression of E-selectin, P-selectin, and intercellular adhesion molecule-1 compared with that for the control (83.0 ± 0.7, 34.8 ± 1.2, and 5.4 ± 0.0 ng/mL, respectively), whereas other progestogens or 17β-estradiol additive to progestogens did not significantly change expression. MPA significantly increased U937 monocytoid cell adherence compared with the control (56.0 ± 1.5 vs 46.5 ± 3.5 adherent cells per 10 fields) but did not increase adherence to HUVECs with knocked down intercellular adhesion molecule-1.

CONCLUSIONS

MPA increases cell adhesion molecule expression on HUVECs, causing increased numbers of monocytoid cells to adhere to HUVECs. These MPA effects may be a risk factor for atherogenesis on endothelial cells in postmenopausal women receiving hormone replacement therapy.

Correlation between steroid hormonal levels and cardiac function in women during controlled ovarian hyperstimulation

During in vitro fertilization-embryo transfer (IVF-ET) treatment, most women require controlled ovarian hyperstimulation (COH). COH with gonadotropins results in an increase in steroid hormonal levels; however, it is unclear what impact these high concentrations of steroid hormones have on cardiac heart function. The purpose of this study was to examine the effect of high levels of estradiol (E2) and progesterone (P) during COH treatment on cardiac function in women undergoing IVF-ET. A total of 34 women with infertility due to tubal or male factors treated with COH and 28 women with normal menstrual cycles who underwent ovulation monitoring only were enrolled in this study. The serum levels of steroid hormones and the parameters of echocardiography at different time points during the natural menstrual cycles of the control group and the corresponding time points during COH treatment of the study group were compared. The independent sample with the t test, the paired sample with t test, χ(2) test, and Pearson correlation analysis were applied. The steroid hormonal levels were significantly different between natural menstrual cycles and COH treatment cycles. Left ventricular end-diastolic volume (LVEDV) reached the highest level on day 7 after oocyte pickup; in contrast, ejection fraction (LVEF) was the lowest level on the same day. On day 16 after ET, E2 and P levels were maintained in the pregnant women in the study group; however, the levels of those hormones returned to those of a natural menstrual cycle in non-pregnant women. The parameters of LVEF and LVEDV significantly correlated with E2 concentrations. High levels of E2 during COH treatment may temporarily affect cardiac function, suggesting that COH intervention is relatively safe; however, a certain level of risk might exist.

Progestogens used in postmenopausal hormone therapy: differences in their pharmacological properties, intracellular actions, and clinical effects

The safety of progestogens as a class has come under increased scrutiny after the publication of data from the Women's Health Initiative trial, particularly with respect to breast cancer and cardiovascular disease risk, despite the fact that only one progestogen, medroxyprogesterone acetate, was used in this study. Inconsistency in nomenclature has also caused confusion between synthetic progestogens, defined here by the term progestin, and natural progesterone. Although all progestogens by definition have progestational activity, they also have a divergent range of other properties that can translate to very different clinical effects. Endometrial protection is the primary reason for prescribing a progestogen concomitantly with postmenopausal estrogen therapy in women with a uterus, but several progestogens are known to have a range of other potentially beneficial effects, for example on the nervous and cardiovascular systems. Because women remain suspicious of the progestogen component of postmenopausal hormone therapy in the light of the Women's Health Initiative trial, practitioners should not ignore the potential benefits to their patients of some progestogens by considering them to be a single pharmacological class. There is a lack of understanding of the differences between progestins and progesterone and between individual progestins differing in their effects on the cardiovascular and nervous systems, the breast, and bone. This review elucidates the differences between the substantial number of individual progestogens employed in postmenopausal hormone therapy, including both progestins and progesterone. We conclude that these differences in chemical structure, metabolism, pharmacokinetics, affinity, potency, and efficacy via steroid receptors, intracellular action, and biological and clinical effects confirm the absence of a class effect of progestogens.

Progesterone improves cognitive performance and attenuates smoking urges in abstinent smokers

BACKGROUND

Progesterone, a steroid hormone, has been implicated in many CNS functions including reward, cognition, and neuroprotection. The goal of this study was to examine the dose-dependent effects of progesterone on cognitive performance, smoking urges, and smoking behavior in smokers.

METHODS

Thirty female and thirty-four male smokers participated in a double-blind, placebo-controlled study. Female smokers were in the early follicular phase of their menstrual cycle during study participation. Smokers were randomly assigned to either 200 or 400mg/day of progesterone or placebo, given in two separate doses, during clinic visit. The first 3 days of the treatment period, smokers abstained from smoking, which was verified with breath CO levels. Smokers attended an experimental session on day 4 where the number of cigarettes smoked were recorded starting 2h after the medication treatment.

RESULTS

Progesterone treatment, 200mg/day, significantly improved cognitive performance in the Stroop and the Digit Symbol Substitution Test. Progesterone at 400mg/day was associated with reduced urges for smoking but did not change ad lib smoking behavior.

CONCLUSIONS

These findings suggest a potential therapeutic value of progesterone for smoking cessation.

Effect of hot flushes on vascular function: a randomized controlled trial

OBJECTIVE

To compare the vascular responses to hormone therapy in women with and without hot flushes.

METHODS

We randomly assigned 143 healthy, recently postmenopausal women (mean age 52.4+/-0.2 years, time since menopause 19.5+/-0.9 months) with intolerable hot flushes (more than seven moderate/severe episodes per day) or tolerable hot flushes (fewer than three mild episodes per day) to receive 1 mg of transdermal estradiol gel, oral estradiol (2 mg) with and without daily medroxyprogesterone acetate, or placebo for 6 months. Vascular function was assessed by pulse-wave analysis and endothelial function testing with nitroglycerin and salbutamol challenges.

RESULTS

Hot flushes did not affect the changes in arterial or aortic stiffness or endothelial function in response to various forms of hormone therapy. However, in women with tolerable hot flushes, oral estradiol caused a decrease of 13.2% (P=.028) in the time to the first systolic peak (dependent on the rapid phase of ventricular ejection) after nitroglycerin. In addition, the time to the reflected wave (dependent on pulse-wave velocity) after nitroglycerin was decreased by 8.4% (P=.018). These effects were not seen in women with intolerable hot flushes or with the other treatment regimens.

CONCLUSION

Women without troublesome hot flushes are susceptible to unfavorable vascular effects after oral estrogen treatment, resulting in less compliant vasculature.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT00668603.

LEVEL OF EVIDENCE

I.