Effect of naloxone on luteinizing hormone secretion in premenstrual syndrome**Supported in part through the General Clinical Research Center funded by the Division of Research Resources of the National Institutes of Health, Bethesda, Maryland, under grant RR-00350

Roles of the µ-opioid receptor and its related signaling pathways in the pathogenesis of premenstrual syndrome liver-qi stagnation

The present study aimed to investigate the roles of the µ-opioid receptor (MOR) and its related signaling pathways in the pathogenesis of premenstrual syndrome (PMS) liver-qi stagnation, along with the therapeutic effects of the Shu-Yu capsule in treating the condition. A PMS liver-qi stagnation rat model was established using a chronic restraint stress method. The protein expression level of MOR within rat hippocampal tissue was detected via western blot analysis and cyclic adenosine monophosphate (cAMP) levels within the supernatant of a rat hippocampal cell culture were determined by ELISA. The western blot analysis indicated that the hippocampal expression level of MOR was significantly elevated in the PMS liver-qi stagnation model group. However, subsequent treatment with a Shu-Yu capsule was found to significantly decrease the level of MOR expression. In addition, in vitro experiments were performed, whereby primary hippocampal neurons were treated with model rat serum. It was observed that the level of MOR expression was significantly elevated, while brain-derived neurotrophic factor (BDNF) and cAMP levels in the culture supernatant were significantly decreased. These effects were reversed by treatment with serum from the Shu-Yu capsule-treated rats. Furthermore, when treated with the MOR activator DAMGO, the following were significantly decreased in the primary neurons: Phosphorylation levels of cAMP response element binding protein and extracellular signal-regulated protein kinases (ERK); BDNF expression; and cAMP content in the culture supernatant. These effects were reversed in primary neurons treated with DAMGO and Shu-Yu-containing rat serum. Collectively, the data suggest that increased MOR expression and activation of the cAMP/ERK signaling pathway in the hippocampus may be involved in the pathogenesis of PMS liver-qi stagnation. Furthermore, the efficacy of the Shu-Yu capsule in treating the condition may be via its regulation of MOR receptor signaling.

The premenstrual tension syndrome rating scales: an updated version

BACKGROUND

The Premenstrual Tension Syndrome (PMTS) Rating Scales have been widely used as inclusion criteria and/or outcome measures in clinical trials of treatment of Premenstrual Syndromes (PMS). However, both the PMTS Observer Rating Scale (PMTS-O) and the PMTS Self Rating Scale (PMTS-SR) are outdated. We propose to bring them in line with the DSM-IV criteria for Premenstrual Dysphoric Disorder (PMDD) by updating the PMTS-O and replacing the PMTS-SR with a Multiple Visual Analogue Scale (PMTS-VAS).

METHODS

A convenience sample of 23 Caucasian, English-speaking women in their reproductive years with regular menstrual cycles was recruited. Participants were administered the revised PMTS-O (PMTS-OR) by a trained clinician and then instructed to complete the PMTS-SR and the new PMTS-VAS, both of which were timed. The participants were also asked which of the instruments they preferred.

RESULTS

The PMTS-OR and the new PMTS-VAS were sensitive to the variation in severity of premenstrual symptoms among the study participants. All 3 questionnaires showed very high inter-correlations. The PMTS-VAS took less time to complete, and most women preferred the PMTS-VAS to the original PMTS-SR, especially those with PMDD and severe PMS.

CONCLUSIONS

By making minor modifications to the PMTS-O we have ensured that all criteria for the DSM-IV definition of PMDD are now represented in the PMTS-OR. The new PMTS-VAS mirrors the PMTS-OR but now also captures the severity of self rated symptoms. These scales are simple to complete for both clinicians and clients, and are reliable, valid and sensitive to change.

Opioidergic mechanisms underlying the actions of Vitex agnus-castus L

Vitex agnus-castus (VAC) has been used since ancient Greek times and has been shown clinically to be effective for the treatment of pre-menstrual syndrome. However, its mechanism of action has only been partially determined. Compounds, fractions, and extracts isolated from VAC were used in this study to thoroughly investigate possible opioidergic activity. First, an extract of VAC was found to bind and activate μ- and δ-, but not κ-opioid receptor subtypes (MOR, DOR, and KOR respectively). The extract was then resuspended in 10% methanol and partitioned sequentially with petroleum ether, CHCl(3), and EtOAc to form four fractions including a water fraction. The highest affinity for MOR was concentrated in the CHCl(3) fraction, whereas the highest affinity for DOR was found in the CHCl(3) and EtOAc fractions. The petroleum ether fraction had the highest agonist activity at MOR and DOR. Several flavonoids from VAC were found to bind to both MOR and DOR in a dose-dependent manner; however only casticin, a marker compound for genus Vitex, was found to have agonist activity selective for DOR at high concentrations. These results suggest VAC may exert its therapeutic effects through the activation of MOR, DOR, but not KOR.

Update on research and treatment of premenstrual dysphoric disorder

Many women in their reproductive years experience some mood, behavioral. or physical symptoms in the week prior to menses. Variability exists in the level of symptom burden in that some women experience mild symptoms, whereas a small minority experience severe and debilitating symptoms. For an estimated 5%-8% of premenopausal women, work or social functioning are affected by severe premenstrual syndrome. Many women in this group meet diagnostic criteria for premenstrual dysphoric disorder (PMDD). Among women who suffer from PMDD, mood and behavioral symptoms such as irritability, depressed mood, tension, and labile mood dominate. Somatic complaints, including breast tenderness and bloating, also can prove disruptive to women's overall functioning and quality of life. Recent evidence suggests that individual sensitivity to cyclical variations in levels of gonadal hormones may predispose certain women to experience these mood, behavioral, and somatic symptoms. Treatments include: antidepressants of the serotonin reuptake inhibitor class, taken intermittently or throughout the menstrual cycle; medications that suppress ovarian cyclicity; and newer oral contraceptives with novel progestins.

Premenstrual syndrome

Most women of reproductive age have some physical discomfort or dysphoria in the weeks before menstruation. Symptoms are often mild, but can be severe enough to substantially affect daily activities. About 5-8% of women thus suffer from severe premenstrual syndrome (PMS); most of these women also meet criteria for premenstrual dysphoric disorder (PMDD). Mood and behavioural symptoms, including irritability, tension, depressed mood, tearfulness, and mood swings, are the most distressing, but somatic complaints, such as breast tenderness and bloating, can also be problematic. We outline theories for the underlying causes of severe PMS, and describe two main methods of treating it: one targeting the hypothalamus-pituitary-ovary axis, and the other targeting brain serotonergic synapses. Fluctuations in gonadal hormone levels trigger the symptoms, and thus interventions that abolish ovarian cyclicity, including long-acting analogues of gonadotropin-releasing hormone (GnRH) or oestradiol (administered as patches or implants), effectively reduce the symptoms, as can some oral contraceptives. The effectiveness of serotonin reuptake inhibitors, taken throughout the cycle or during luteal phases only, is also well established.

Activation of the mu-opiate receptor by Vitex agnus-castus methanol extracts: implication for its use in PMS

The dried ripe fruit of Vitex agnus-castus L. (VAC) is widely used for the treatment of premenstrual syndrome (PMS). A previous study reported that extracts of VAC showed affinity to opiate receptors; however, functional activity was not determined. We tested two different VAC extracts in receptor binding and functional assays. Our objectives were: (1) to confirm the opiate affinity; (2) to rule out interference by free fatty acids (FFA); (3) to determine the mode of action of VAC at the mu-opiate receptor. Methanol extracts of VAC were prepared either before (VAC-M1) or after (VAC-M2) extraction with petroleum ether to remove fatty acids. Both extracts showed significant affinities to the mu-opiate receptor, as indicated by the concentration-dependent displacement of [3H]DAMGO binding in Chinese hamster ovary (CHO)-human mu-opiate receptor (hMOR) cells. The IC50 values were estimated to be 159.8 microg/ml (VAC-M1) and 69.5 microg/ml (VAC-M2). Since the defatted extract not only retained, but exhibited a higher affinity (p<0.001), it argued against significant interference by fatty acids. In an assay to determine receptor activation, VAC-M1 and VAC-M2 stimulated [35S]GTPgammaS binding by 41 and 61% (p<0.001), respectively. These results suggested for the first time that VAC acted as an agonist at the mu-opiate receptor, supporting its beneficial action in PMS.

Differential response to estrogen challenge test in women with and without premenstrual dysphoria

This study tested the hypothesis that brain sensitivity to normal fluctuations in gonadal hormones is increased in women with premenstrual dysphoria. For this purpose, the effect of a common gonadal hormonal challenge on the sensitivity of the brain was investigated in 13 women with premenstrual dysphoria and 12 asymptomatic controls. The estrogen challenge test, comprising estradiolbenzoate 0.04 mg/kg, was given as an intramuscular gluteal injection between 0700 and 1000h on day 3 or 4 of the menstrual cycle; blood was sampled at 0, 0.6, 6.5, 24, 32, 48, 56, 72, 96, 120, and 144h and analyzed for estradiol, FSH and LH. Serum estradiol levels after the injection and the corresponding FSH responses were similar between the study groups; however, the LH responses were significantly different. Women with premenstrual dysphoria had a relatively stronger negative feedback response (p=0.014) up to the point of nadir LH levels (maximal negative feedback), but displayed higher LH levels at the nadir (p=0.01), more LH surge-like reactions (p=0.047), and a 50% higher area under the curve (AUC) for LH (p=0.03) than controls. The LH response in women with premenstrual dysphoria was related to the VAS-rated symptoms; the negative increment (AOC) correlated to luteal phase "bloating" (r(s)=0.73; p=0.0069) whereas the AUC of LH correlated to "irritability" (r(s)=0.58; p=0.040). A significant interaction term between study group and changes in LH during the negative feedback phase (32-0h), with regard to luteal phase "irritability" was found (test for interaction p=0.005). For the premenstrual dysphoria group, ratings of "depressed mood"were related to baseline FSH levels (r(s)=0.60; p=0.034), and to the AUC of FSH during the negative feedback phase (r(s)=0.58; p=0.043). Women with premenstrual dysphoria displayed a gonadotrophin response to estradiol challenge that differed from that of controls, and was correlated to symptom severity.

Gonadotropin-releasing hormone-stimulated gonadotropin levels in women with premenstrual dysphoria

Despite consistent evidence that premenstrual dysphoria (PMD) is not characterized by abnormalities in basal ovarian hormone secretion, the possibility remains that PMD is associated with an abnormality in the regulation of the hypothalamic-pituitary-ovarian (HPO) axis. We studied HPO axis regulation in 11 women with prospectively confirmed PMD and 20 asymptomatic controls, during both the follicular and luteal phases of the menstrual cycle. Plasma levels of the gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), were obtained before and after stimulation with gonadotropin-releasing hormone (GnRH) (100 microg intravenously). Potential diagnostic- and menstrual cycle phase-related diferences in basal and plasma hormone levels were analyzed by repeated-measures analysis of variance. No significant differences were observed between women with PMD and controls in either basal or stimulated levels of FSH and LH. Stimulated FSH was significantly increased and stimulated LH was significantly decreased during the follicular compared with the luteal phase in both women with PMD and controls. These data are consistent with prior findings of normal basal reproductive hormone levels in women with PMD. Our data suggest the absence in women with PMD of an abnormality of dynamic ovarian function as measured by GnRH stimulation.

Diagnosis and treatment of premenstrual dysphoric disorder

Premenstrual syndrome (PMS) is a common problem and patients with PMS are encountered by obstetricians, gynecologists, family practitioners, internists (general physicians) and psychiatrists. Despite several decades of biological research, the etiology of the disorder is still elusive. The introduction of a psychiatric category called premenstrual dysphoric disorder (PMDD), describing women with severe emotional premenstrual symptoms, has advanced biological treatment research by identifying a more homogeneous patient population. This paper aims to review our current understanding of the clinical presentation, underlying psycho-biology, and essentials of treatment for premenstrual dysphoric disorder.