Endogenous opioid activity and the premenstrual syndrome

Towards understanding the biology of premenstrual dysphoric disorder: From genes to GABA

Premenstrual dysphoric disorder (PMDD) is a severe mood disorder, with affective symptoms that rise and fall in concert with the hormonal fluctuations of the menstrual cycle. PMDD's pathophysiology is poorly understood. This review describes recent research on potential biological contributors to PMDD, with a focus on neuroactive steroids, genetics, neuroimaging and cellular studies. Studies suggest that a key contributor is abnormal central nervous system (CNS) response to fluctuations in neuroactive steroid hormones. Imaging studies are limited but support alterations in serotonergic and GABA transmission. Genetic studies suggest heritability, yet specific genetic contributors have not been characterized. Finally, recent cutting-edge cellular studies indicate an underlying vulnerability to the effect of sex hormones at a cellular level. Overall the findings across studies do not yet fit together into a complete description of the underlying biology of PMDD. It is possible that PMDD consists of biological subtypes, and future research may benefit from a subtyping approach.

One woman's low is another woman's high: Paradoxical effects of the menstrual cycle

Although past research on affective changes associated with the menstrual cycle has focussed on a specific pattern commonly referred to as Premenstrual Syndrome, there are compelling reasons to hypothesize that an opposite pattern, with a mid-cycle increase and a premenstrual low in symptoms, may also exist. Focusing on depression and anxiety, the present study tested whether this mid-cycle pattern of symptoms could be identified, using a sample of 213 female university students, who completed daily questionnaires for two menstrual cycles. Results confirmed the existence of a group of women who demonstrate the mid-cycle pattern of symptom changes (13%), in addition to the classic PMS pattern (61%), and individuals demonstrating no cyclical pattern of symptoms (26%). Moreover, women with a strong PMS pattern showed lower average levels of depression/anxiety than women with no cyclical changes. These findings require that current conceptions of menstrual-cycle related psychological changes be redefined to include the mid-cycle pattern, and suggest that women with strong PMS symptoms may actually benefit from a mid-cycle sense of wellness.

Premenstrual exacerbation of symptoms in multiple sclerosis is attenuated by treatment with weak electromagnetic fields

It has been suspected that hormonal factors contribute to the etiology and pathogenesis of multiple sclerosis (MS). A direct relationship between MS and endocrine functions is suggested by changes in disease activity during the phases of the menstrual cycle. A subset of women with MS experience premenstrual worsening of symptoms which improve dramatically with the onset of menstruation. The biological mechanisms underlying these changes in disease activity are unexplained but may be related to cyclical fluctuations in gonadal sex steroid hormones, abrupt changes in the activity of the endogenous opioid peptides and fluctuations in plasma melatonin levels which affect neuronal excitability and immune functions. Extracerebral application of weak electromagnetic fields (EMFs) in the picotesla range intensity has been reported efficacious in the treatment of MS with patients experiencing sustained improvement in motor, sensory, autonomic, affective and cognitive functions. The present report concerns two women with chronic progressive stage MS who experienced, coincident with increasing functional disability, regular worsening of their symptoms beginning about a week before menstruation and abating with the onset of menstruation. These symptoms resolved two months after the initiation of treatment with EMFs. The report supports the association between the endocrine system and MS and indicates that brief, extracranial applications of these magnetic fields modifies the activity of neuroendocrine systems which precipitate worsening of MS symptoms premenstrually.

Peripheral plasma met-enkephalin levels in ovulatory and anovulatory human menstrual cycles

OBJECTIVE

To test the hypothesis that met-enkephalin has a role in human ovulation and that plasma levels may differ between ovulatory and anovulatory ovarian cycles.

DESIGN

This is a descriptive study comparing levels of plasma met-enkephalin, gonadotropins, and ovarian steroids in 12 ultrasonically confirmed ovulatory cycles and 12 anovulatory cycles.

SETTING

The study took place in the infertility clinic of a large teaching hospital receiving primary and tertiary referrals of both private and public sector patients.

PATIENTS

All patients (n = 16) had infertility greater than or equal to 3 years and normal findings on previous investigation including evidence of ovulation.

INTERVENTIONS

Ovarian cycles were defined using transabdominal ultrasound scanning. Biochemical analyses were by radioimmunoassay.

MAIN OUTCOME MEASURES

The differences between plasma met-enkephalin levels in the two groups of cycles were compared.

RESULTS

Met-enkephalin levels are significantly higher in ovulatory cycles with a significant peak in the 2 postovulatory days (Duncan's multiple range test; P less than 0.05).

CONCLUSION

Human ovulation is associated with cyclic elevation of plasma met-enkephalin. Further studies are required to elucidate causality.

Buserelin in premenstrual syndrome

Buserelin, a luteinizing hormone releasing hormone agonist was administered nasally in doses of 900 micrograms daily to inhibit the ovarian cycle. Of 16 patients recruited, ten completed the treatment. Daily symptoms were measured on the Visual Analogue Scale and Trigg's trend analysis utilized for the analysis. The peak severity of symptoms (ESAmax) and the maximum global scores (Gmax) reduced on buserelin treatment. The minimum global scores (Gmin) and the minimum score for each symptom (ESAmin) increased, suggesting worsening of underlying symptoms. The difference between ESAmax and ESAmin (ESAdelta) and Gmax and Gmin (Gdelta) were calculated to determine the degree of symptom change. The delta scores for symptoms of depression, bloatedness and breast symptoms, and Gdelta were significantly reduced (p less than 0.05) on buserelin, whilst the latter significantly worsened in the follow-up months. Side-effects may limit the place of buserelin in the long-term treatment of premenstrual syndrome, although combination of additional hormonal treatment may facilitate long-term treatment.

Current concepts of beta-endorphin physiology in female reproductive dysfunction

beta-Endorphin has a role in the regulation of the normal menstrual cycle and possibly in the onset of puberty. We have reviewed the evidence pointing to an alteration in this neuropeptide that may contribute to the pathogenesis of various reproductive dysfunctions. Elevated or high levels of beta-endorphin have been associated with exercise-associated amenorrhea, stress-associated amenorrhea, and polycystic ovarian syndrome. Depressed or low levels of beta-endorphin have been associated with PMS and menopause. Alterations in the levels of beta-endorphin may change the pulsatile release of GnRH via noradrenergic and/or dopaminergic pathways. We have primarily focused on beta-endorphin as representative of the endogenous opioid peptides, but other opioid peptides may also contribute to the pathogenesis of various types of reproductive dysfunction. Perhaps it will become possible to characterize and hone our understanding of the function of beta-endorphin and the other substances composing the endogenous opioid peptides. A better understanding of their role in physiological as well as pathophysiological processes may allow for the development of rational approaches to the treatment of specific disorders pertaining to reproduction. Many questions remain unanswered. Among the most relevant are: what is the precise mechanism of action by which beta-endorphin exerts its influence on pulsatile GnRH release? Is there a functional relationship between CNS and peripheral (serum) levels of beta-endorphin? Are the detected changes in beta-endorphin levels merely associated, or are they a cause of a particular disorder? Since it took almost 40 years between the time prostaglandins were first discovered and eventual realization of their clinical application, it may take some time before the beta-endorphin story is complete.

The hypothalamus in Tourette's syndrome

Although a recent report by Devinsky (1983) has suggested that dysfunction at a midbrain levels is most likely to underlie the major symptoms of Tourette's syndrome, several features of the disease including alterations in the severity of the disease during puberty and premenstrually, disorders of appetite, amelioration of tics with rise in body temperature, and sleep point to hypothalamic involvement in the pathophysiology of the disease.

Plasma beta-endorphin immunoreactivity in premenstrual tension

Plasma samples were collected twice during the follicular phase and three times during the luteal phase of the menstrual cycle in 12 women with premenstrual tension (PMT) and in 14 control subjects without symptoms. Concentrations of beta-endorphin (beta-E) immunoreactivity, cortisol, oestradiol, progesterone and LH were determined. Comparison of the mean concentrations of LH, cortisol, oestradiol and progesterone did not reveal any statistically significant differences between the PMT and the control groups. In the early luteal phase, the mean plasma beta-E immunoreactivity was lower in the PMT group (10.7, SE 0.7 pg/ml) than in the control group (14.6, SE 1.6 pg/ml, P less than 0.05), suggesting that endorphin secretion is decreased in PMT. No significant change in the plasma beta-E level was found in the PMT patients between the follicular and luteal phase when symptoms appeared. This does not exclude the possibility that in the central nervous system abnormal changes occur in the activity of endogenous opioids in PMT.

Premenstrual dysphoric disorder: evaluation, pathophysiology and treatment

A small percentage of women describe a prominent dysphoric disturbance that is present during the premenstrual week, remits soon after the onset of menses and produces significant impairment in domestic, social or occupational functioning. Premenstrual dysphoric disorder must be distinguished from minor premenstrual emotional changes, from dysmenorrhea and from premenstrual exacerbations of psychiatric illness. Diagnostic evaluation should include the prospective assessment of symptoms over at least two complete menstrual cycles. Although the pathophysiology of premenstrual dysphoric disorder is linked to cycling of the intact hypothalamo-pituitary-gonadal axis, many studies have contained serious methodological weaknesses and no single etiological theory has received widespread support. No single pharmacological treatment has been shown to be clearly more effective than placebo in controlled studies and premenstrual dysphoric disorder appears to respond favorably to most interventions in uncontrolled studies. Interruption of pituitary-ovarian cycling will alleviate premenstrual symptoms, but treatments of this type cannot be recommended for general use until potential hazards are clarified.

Suicide attempts in hypo-oestrogenic phases of the menstrual cycle

The phase of the menstrual cycle in women who had attempted suicide was determined by structured interview. 108 young women were investigated within 24 h of the attempt. Patients were grouped according to menstrual week and whether they used oral contraception (OC) (n = 73) or not (n = 35). In OC non-users suicide attempts were associated with low plasma oestradiol: they tended to happen during the first week of the menstrual cycle (42%) and after the fourth week (12%). Frequency of suicide attempts did not vary significantly during the menstrual cycle in OC users. In OC non-users, low oestradiol production may predispose to depression and attempted suicide.

Pre-menstrual syndrome--are gonadotropins the cause of the condition?

It is proposed that premenstrual syndrome results from the action of elevated gonadotropin levels in various tissues of body other than their natural target organs. These levels are derived from an increased sensitivity to estrogen after pregnancy, childbirth, etc., particularly with respect to the positive feedback on gonadotropin release from the pituitary. Estrogen in conjunction with gonadotropin-releasing hormone (GnRH) releases excessive amounts of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) at ovulation and in the premenstrual phase (post-menopausal patients have greatly elevated gonadotropins and can also demonstrate cyclic symptoms). Gonadotropin action via adenylate cyclase in the adrenal cortex elevates cortisol, while antagonism of parathyroid hormone action on bone gives rise to hypocalcemia. The physiological and psychological symptoms may thereby be explained.

Review of the etiology and treatment of premenstrual syndrome

Premenstrual syndrome (PMS) is a diagnostic enigma that causes significant morbidity in many woman. Numerous theories have been proposed in an attempt to explain the varied symptoms that occur cyclically in women with PMS. Suggested etiologic theories of PMS include psychological abnormalities, nutritional deficiencies, aberrations in the renin-angiotensin-aldosterone axis, altered prostaglandin activity, hormonal imbalances, and changes in endogenous opioid peptide activity. Because of the lack of standardized diagnostic criteria, clinical drug trials for PMS have been severely compromised. For every proposed cause of PMS, there exists a drug or drug class that has been investigated for treatment of the associated symptoms. Many clinical studies are uncontrolled, a significant deficiency in study design for a disorder that is associated with a high placebo response rate. At the present time, no definitive treatment for PMS exists and therapy must be individualized according to clinical response. This review article defines PMS, describes one of the current approaches to the diagnostic work-up, discusses the proposed etiologies of PMS, and reviews the various proposed treatment modalities.