Mechanism of hot flashes

Vasomotor symptoms of menopause, autonomic dysfunction, and cardiovascular disease

Cardiovascular disease (CVD), the leading cause of death among US adults, is more prevalent in menopausal females compared with age-matched males. Vasomotor symptoms of menopause (VMS; hot flashes/flushes and night sweats) are common among females undergoing menopausal transition and have been associated with elevated blood pressure (BP) and increased CVD risk. Autonomic dysregulation of BP has been posited as a contributing factor to the elevated CVD risk in menopausal females with VMS. This review includes 1) a brief overview of the relationship between VMS and CVD, 2) mechanisms of hot flushes and their potential impact on short- and long-term BP regulation, and 3) how the disruption of autonomic function associated with VMS might provide a mechanistic pathway to CVD development. Finally, this review will highlight knowledge gaps and future directions toward better understanding of hot flush physiology and VMS contributions to CVD.

Non-hormonal strategies for managing menopausal symptoms in cancer survivors: an update

Vasomotor symptoms, particularly hot flushes (HFs), are the most frequently reported symptom by menopausal women. In particular, for young women diagnosed with breast cancer, who experience premature ovarian failure due to cancer treatments, severe HFs are an unsolved problem that strongly impacts on quality of life. The optimal management of HFs requires a personalised approach to identify the treatment with the best benefit/risk profile for each woman. Hormonal replacement therapy (HRT) is effective in managing HFs but it is contraindicated in women with previous hormone-dependent cancer. Moreover, many healthy women are reluctant to take HRT and prefer to manage symptoms with non-hormonal strategies. In this narrative review, we provide an update on the current available non-oestrogenic strategies for HFs management for women who cannot, or do not wish to, take oestrogens. Since isoflavones have oestrogenic properties and it is not known if they can be safely consumed by women with previous hormone-dependent cancer, they were excluded. Selective serotonin reuptake inhibitors/selective serotonin-norepinephrine reuptake inhibitors, as well as other neuroactive agents, some herbal remedies and behavioural strategies are considered.

Novel effect of α-lactalbumin on the yohimbine-induced hot flush increase of the tail skin temperature in ovariectomized rats

5-Hydroxytryptamine (5-HT) and noradrenaline have been thought to play important roles in the mechanism of hot flush. Then, to clarify the relation between serotonergic and adrenergic nervous systems on the mechanism of hot flush, the effect of paroxetine, 5-HT reuptake inhibitor (SSRI) was evaluated on the yohimbine-induced hot flush increase of tail skin temperature in ovariectomized female rats. Yohimbine (adrenaline α₂ antagonist) significantly increased the tail skin temperature in course of time. Clonidine (adrenaline α₂ agonist) significantly attenuated this effect. Paroxetine also significantly inhibited the increase of tail skin temperature by yohimbine. α-Lactalbumin having SSRI activity in vitro study also significantly inhibited the increase of tail skin temperature, but not significantly decreased the initial temperature. This difference may explain the different mechanism between paroxetine (SSRI) and α-lactalbumin, suggesting new mechanism of hot flush.

Duloxetine and escitalopram for hot flushes: efficacy and compliance in breast cancer survivors

Selective serotonin reuptake inhibitors (SSRI) and serotonin-norepinephrine reuptake inhibitors (SNRI) might be an effective treatment for hot flushes (HFs) in breast cancer survivors (BCSs). This study aims to compare the efficacy and tolerability of duloxetine (SNRI) versus escitalopram (SSRI) in reducing frequency and severity of HFs in BCSs and to assess the effect on depression. Thirty-four symptomatic BCSs with emotional impairment received randomly duloxetine 60 mg daily or escitalopram 20 mg daily for 12 weeks. Patients were asked to record in a diary HF frequency and severity at baseline and after 4 and 12 weeks of treatment. Depression was evaluated through validated questionnaires (Beck Depression Inventory and Montgomery Asberg Depression Rating Scale) at baseline and after 4 and 12 weeks of treatment. Both drugs showed a significant reduction of HF frequency and severity after 12 weeks of treatment with no significant difference between the two groups. A significant improvement in depression symptoms was observed at the end of the study period within both the groups, without difference between the two drugs. In conclusion, escitalopram and duloxetine are both effective treatment for the relief of HFs in BCSs, with similar beneficial effect. A significant improvement of depression was obtained with no major side effects.

Menopause in multiple sclerosis: therapeutic considerations

While the onset of multiple sclerosis (MS) typically occurs during the childbearing years, many women living with MS are of perimenopausal age. There is frequent overlap between menopausal and MS-related symptoms and co-morbidities (e.g. sexual dysfunction, mood disorders and bladder function). Furthermore, some MS symptoms may be exacerbated by perimenopausal changes such as hot flashes or sleep disturbance. The MS neurologist may frequently be the first to become aware of these symptoms and to play a role in monitoring and managing them. In this review, we describe immunological and neurologic changes at menopause as they may impact MS. We then review common symptoms, including fatigue, depression, sexual function, pain and insomnia, and provide both behavioral and pharmacological suggestions for their management. Next, we discuss the need for osteoporosis and cancer screening in perimenopausal women with MS. Finally, we highlight important research gaps, including what effect, if any, the menopausal transition may play on MS disease course as well as the potential modulatory role of hormone replacement therapies.

MF101: a multi-component botanical selective estrogen receptor beta modulator for the treatment of menopausal vasomotor symptoms

INTRODUCTION

The Women's Health Initiative Estrogen Plus Progestin clinical trial demonstrated the risks exceeded the benefits which have led to a decline in menopausal hormone therapy (MHT) by greater than 50%. MHT use was initiated long before there was a significant understanding of the molecular mechanisms of estrogens. It has become clear that the problem with the current estrogens in MHT is they act non-selectively as an agonist in all tissues that contain estrogen receptors. MF101 is an oral, botanically derived extract that was designed to selectively regulate estrogen receptor beta (ERβ) because the increased risk of breast and endometrial cancer is due to the activation of estrogen receptor alpha (ERα) by estrogens. Preclinical and clinical data support a role for selective ERβ agonists, such as MF101, for vasomotor symptoms without increasing cancer risks.

AREAS COVERED

The review covers the biological, pharmacological and clinical advantages of MF101, and the unique ability of MF101 to selectively target the ERβ pathway for the treatment of hot flashes (HF).

EXPERT OPINION

Preclinical and clinical studies indicate that MF101, a selective estrogen receptor beta agonist, represents a new class of drugs that is safe and effective for treating HF and nighttime awakenings.