Progesterone, progestins and the endometrium in perimenopause and in menopausal hormone therapy

The "double-edged" role of progesterone in periodontitis among perimenopausal women undergoing or not undergoing scaling and root planing

Objective

Progesterone (PG) is an important sex steroid hormone commonly administered to protect the endometrium in perimenopausal women. The present study aimed to explore differential responses of periodontitis to PG in perimenopausal women who did or did not undergo scaling and root planing (SRP).

Methods

A total of 129 perimenopausal women with mild-to-moderate periodontitis were enrolled and underwent treatment as follows: SRP (n = 35); SRP + PG (n = 34); PG (n = 31); and no treatment (s) (n = 29). Pocket probing depth (PPD), clinical attachment level (CAL), sulcus bleeding index (SBI), and bleeding on probing (BOP) were measured using periodontal probes. Three inflammatory markers, including C-reactive protein (CRP), interleukin (IL)-6, and tumor necrosis factor-alpha (TNF-α) in gingival crevicular fluid (GCF) were measured using ELISA techniques.

Results

PPD, CAL, SBI, BOP, and levels of inflammatory factors in GCF were all significantly decreased in perimenopausal women with periodontitis after SRP. In patients who did not undergo SRP, 6 months of PG treatment significantly elevated PPD, SBI, BOP, and GCF levels of CRP, IL-6, and TNF-α. In contrast, PG exhibited inhibitory effects on periodontal inflammation in patients who underwent SRP, evidenced by significantly decreased BOP and IL-6, and slightly decreased SBI, CRP, and TNF-α. PG-induced changes dissipated 6 months after withdrawal of PG (at 12 months).

Conclusions

Among perimenopausal women with periodontitis, PG enhanced periodontal inflammation in the absence of SRP but inhibited periodontal inflammation in those who underwent SRP.

Understanding Progestins: From Basics to Clinical Applicability

Progestin is a term used to describe a synthetic progestogen. The activity and potency of synthetic progestins are mostly evaluated via parameters associated with their endometrial effects, which are related to their interactions with progesterone, estrogen, androgen, glucocorticoid, and mineralocorticoid receptors. The chemical structure of progestins is the key to understanding their interactions with these receptors and predicting the other effects associated with these drugs. Due to their endometrial effect, progestins are used for different gynecological conditions, such as endometriosis, contraception, hormonal replacement therapy, and artificial reproduction techniques. This review is focused on improving our knowledge of progestins (from their history and biochemical effects related to their chemical structures to clinical applications in gynecological conditions) in order to improve clinical practice.

Drugs for the treatment of postmenopausal symptoms: Hormonal and non-hormonal therapy

Postmenopausal symptoms are systemic symptoms associated with estrogen deficiency after menopause. At present, treatments for postmenopausal symptoms include hormonal therapy (HT) and non-HT. However, the optimal regimen for balancing the benefits and risks remains unclear. This article reviewed the characteristics, regimens, and side effects of drugs used in hormonal and non-HT. However, HT is still the most effective treatment with safety in early initiation since menopause onset. Nevertheless, it is essential to evaluate the risks of related chronic diseases and customize individualized treatments. Possible estetrol preparations and more types of Tissue Selective Estrogen Complex formulations are potential directions of drug development in the future of HT. Regarding non-HT, fezolinetant, currently in phase III clinical trials, is poised to become a first-in-class therapy for vasomotor symptoms. Ospemifene, dehydroepiandrosterone (DHEA), and vaginal lasers can also be used for moderate-to-severe genitourinary syndrome of menopause. Recent data suggest a superior efficacy and safety of vaginal lasers, but more validated evidence of long-term tolerability is needed to respond to the United States Food and Drug Administration warning. Herbal medication commonly used in Asia is effective in alleviating menopausal symptoms; however, its adverse effects still require more detailed reports and standardized observation methods. This review contributes to a better understanding of drugs for the treatment of postmenopausal symptoms and provides useful information for clinical drug selection.

Primary choice of estrogen and progestogen as components for HRT: a clinical pharmacological view

Prescribing hormone replacement therapy (HRT) requires consideration of the selection of its two components, the estrogen and the progestogen. In terms of the estrogen, the decision is mainly whether to use estradiol (E2) or conjugated equine estrogens (CEE). These are the components needed to efficiently treat climacteric symptoms or/and prevent osteoporosis, currently the only labeled indications. There is still controversy regarding the adequate dosages comparing E2 and CEE; however, the consensus is that the differences in the efficacy of E2 and CEE are not a real issue. Therefore, other criteria have to be used. The first reason to add the progestogen is to avoid the development of endometrial cancer (i.e. to achieve 'endometrial safety'). Any available 'fixed-combined' HRT preparation has to be tested for sufficient endometrial efficacy, because the first question the health authorities ask before product registration relates to endometrial safety. We can generally rely on the endometrial safety of these fixed-combined products. However, it could be that we want to use 'free' combinations, which are necessary if we use transdermal E2 (patches, gel, spray), but also to individualize schedules, for example when treating bleeding problems. The question here is how to attain knowledge about the endometrial efficacy of the different progestogens and how to monitor therapy. We will try to answer these two questions from a 'clinical pharmacology' point of view, as a discipline which preferably considers pharmacological properties, but also relating to clinical practice, to achieve individualized therapy with optimal efficacy, best tolerability and minimal risks.

Exogenous progesterone short-termly affects the periodontal environment in perimenopausal women

OBJECTIVE

This study aimed to evaluate the effects of exogenous progesterone in the periodontal environment of perimenopausal women.

METHODS

Either with or without periodontitis, 100 perimenopausal women received 3 months of progesterone treatment, as well as age-matched 100 perimenopausal and 100 postmenopausal women without treatments were enrolled (N = 50). The gingival index (GI), probing depth (PD), clinical attachment level (CAL), and tooth mobility (TM), as well the gingival crevicular fluid (GCF) levels of IL-6 and TNF-α were analyzed.

RESULTS

Periodontitis showed higher GI, PD, and CAL than non-periodontitis at perimenopausal and postmenopausal periods. In women without periodontitis, the GI and PD, and the GCF levels of IL-6 and TNF-α were increased by 3 months of progesterone treatment, but recovered from the 6^th month in the absence of progesterone. In women with periodontitis, only the PD was short-termly increased by progesterone treatment. For those without progesterone treatment, the GI, PD, and TM were not significantly different between perimenopausal and postmenopausal women either with periodontitis or not.

CONCLUSIONS

Exogenous progesterone short-termly exacerbated the inflammation and PD in perimenopausal women without periodontitis, and the PD in those with periodontitis.

Update on hormone therapy for the management of postmenopausal women

Hormone therapy (HT) has been used in postmenopausal women for decades in clinical practice. With further analysis and newer studies, the benefits and risks of HT have been repeatedly verified and discussed. HT is recommended for the treatment of vasomotor symptoms (VMS), genitourinary syndrome of menopause (GSM) and the prevention of osteoporosis. However, the precise association between HT and the risks of cardiovascular diseases, venous thromboembolism, neurodegenerative diseases, breast cancer, and endometrial cancer remains controversial. Therefore, determining how to take advantage of and control the risks of HT by adjusting the initiation time, regimen, and duration is crucial. Recent studies have indicated that HT is not related to the risk of all-cause, cardiovascular, or breast cancer mortality although it might increase the incidence of some chronic diseases. For symptomatic postmenopausal women under the age of 60 without contraindications, early initiation of HT is safe and probably has a mortality benefit over the long term. Initiating HT close to menopause at the lowest effective dose is more likely to have maximal benefits and the lowest risks. Transdermal and vaginal HT may have a lower risk, but recent evidence suggests additional clinical benefits of oral HT formulations in relieving VMS and preventing osteoporosis. The pooled cohort risk equation for atherosclerotic cardiovascular disease (ASCVD) and the free app named Menopro can be used to perform individual risk assessments. In addition, Chinese herbal medicines have benefits in alleviating hot flashes, depression, and menopausal symptoms, although further data are needed to strongly support their efficacy. Acupuncture and electroacupuncture have definite efficacy in the treatment of postmenopausal symptoms with few adverse effects, so they are a reasonable option as an alternative therapy for high-risk women. This review discusses the history of, guidelines on, and strategies for HT in order to make suggestions based on the most up-to-date evidence for the management of postmenopausal women.

Clinical Use of Progestins and Their Mechanisms of Action: Present and Future (Review)

This review summarizes the current opinions on the mechanisms of action of nuclear, mitochondrial, and membrane progesterone receptors. The main aspects of the pharmacological action of progestins have been studied. Data on the clinical use of gestagens by nosological groups are presented. Particular attention is paid to progesterone, megestrol acetate, medroxyprogesterone acetate due to broadening of their spectrum of action. The possibilities of using gestagens as neuroprotectors, immunomodulators, and chemosensitizers are considered.

Progesterone and abnormal uterine bleeding/menstrual disorders

This chapter explores the role of progesterone and progestogens in the management of abnormal uterine bleeding (AUB). Progestogens are used to regulate intermenstrual bleeding and decrease heavy menstrual bleeding (HMB) in women of reproductive age or who are perimenopausal. In menopausal women, progesterones and progestogens prevent endometrial hyperplasia and aim to reduce the development of endometrial cancer. We hope to make clear current best practice including preparation, specific benefits and risks. Progesterone also acts in concert with other hormones to affect breast, cardiovascular system, lipid profile and bone. We hope to explain how its unintended side effects may be used beneficially or may cause intended side effects.

Progesterone and endometrial cancer

It is well established that unopposed estrogen, either endogenous or therapeutic, can induce endometrial hyperplasia and potentially endometrial cancer (EC). Anovulatory cycles, obesity, and insulin resistance are major risk factors for EC. Progestogen (progesterone and progestin), including levonorgestrel intrauterine device, are able to prevent or to treat hyperplasia, atypical hyperplasia, and even well-differentiated EC, as presented in this review. During menopausal hormone therapy, progestogens protect the endometrium against the proliferative effects of estrogens in women with a uterus. Whereas, recent epidemiologic data suggest that micronized progesterone (MP) is apparently safer for the breast, it could be less efficient than synthetic progestin on the endometrium. However, several studies from biopsies during treatment with MP do not show any increased risk of hyperplasia. Lack of compliance could explain the results on EC.

Hypothyroidism induces uterine hyperplasia and inflammation related to sex hormone receptors expression in virgin rabbits

AIMS

In women, uterine alterations have been associated with sex steroid hormones. Sex hormones regulate the expression of thyroid hormone receptors (TRs) in the uterus, but an inverse link is unknown. We analyzed the impact of hypothyroidism on histological characteristics, vascular endothelial growth factor (VEGF-A), progesterone receptors (PR), estrogen receptors (ER), thyroid hormone receptors (TRs), perilipin (PLIN-A), and lipid content in the uterus of virgin rabbits.

MAIN METHODS

Twelve Chinchilla-breed adult female rabbits were grouped into control (n = 6) and hypothyroid (n = 6; 0.02% of methimazole for 30 days). The thickness of endometrium and myometrium, number of uterine glands, and infiltration of immune cells were analyzed. The expression of VEGF-A, PR, ERα, and PLIN-A was determined by RT-PCR and western blot. The uterine content of triglycerides (TAG), total cholesterol (TC), and malondialdehyde (MDA) was quantified.

KEY FINDINGS

Hypothyroidism promoted uterine hyperplasia and a high infiltration of immune cells into the endometrium, including macrophages CD163+. It also increased the expression of VEGF-A, TRA, and ERα-66 but reduced that of PR and ERα-46. The uterine content of PLIN-A, TAG, and TC was reduced, but that of MDA was augmented in hypothyroid rabbits.

SIGNIFICANCE

Our results suggest that uterine hyperplasia and inflammation promoted by hypothyroidism should be related to changes in the VEGF-A, PR, ER, and TRs expression, as well as to modifications in the PLIN-A expression, lipid content, and oxidative status. These results suggest that hypothyroidism should affect the fertility of females.

Estradiol and progesterone bioavailability for moderate to severe vasomotor symptom treatment and endometrial protection with the continuous-combined regimen of TX-001HR (oral estradiol and progesterone capsules)

Objective:

In the REPLENISH trial, women receiving TX-001HR—an oral, softgel capsule, combining 17β-estradiol (E2) and progesterone (E2 mg/P4 mg 1/100, 0.5/100), had significantly improved vasomotor symptoms, while having their endometrium protected from hyperplasia. The objective here was to describe P4 levels sufficient to counteract the potential endometrial effects of 1 or 0.5 mg oral E2 with TX-001HR.

Methods:

In REPLENISH (phase 3; NCT01942668), serum P4, E2, and estrone (E1) levels were characterized in postmenopausal women treated with TX-001HR (E2 mg/P4 mg: 1/100, 0.5/100, [0.5/50, 0.25/50 and placebo not reported here]) at baseline, week 12, and month 12 for P4, and at baseline, weeks 4 and 12, and months 6, 9, and 12 for E2 and E1. In a phase 1 study, pharmacokinetic parameters were assessed after 7 daily doses of oral E2 mg/P4 mg (1/100 and 0.5/100).

Results:

In REPLENISH (n = 1,835), mean P4 levels were 0.39 to 0.55 ng/mL with 100-mg P4 doses; E2 levels were 42.3 to 45.6 pg/mL and 23.0 to 27.4 pg/mL for the 1-mg and 0.5-mg E2 doses, respectively; E1 levels were 214 to 242 pg/mL and 114 to 129 pg/mL for the 1-mg and 0.5-mg E2 doses. In the phase 1 study (n = 40; day 7), mean C_avg for P4 was 0.66 ng/mL with 100-mg P4 doses; E2 was 38.1 pg/mL and 29.2 pg/mL for 1 mg and 0.5 mg E2, respectively; and E1 was 211 and 106 pg/mL for 1 mg and 0.5 mg E2. All three analytes reached steady state within 7 days; accumulation ratios were 1.36 to 1.94.

Conclusions:

P4 levels observed with TX-001HR were similar in the phase 1 and 3 studies, and were associated with no endometrial hyperplasia with either E2 daily dose over 1 year in the REPLENISH phase 3 study, which showed significant improvements in menopausal vasomotor symptoms.