Neuroactive properties of reproductive steroids

Ovariectomy induces hyperalgesia accompanied by upregulated estrogen receptor α and protein kinase B in the rat spinal cord

Hormone supplementation is one of the common therapies for menopause-related disorders. Among different tools, the ovariectomy (OVX) rodents are widely accepted as an appropriate menopausal pain model. Our previous study has showed that OVX produces a significant pain facilitation in both acute pain and tonic pain, however, the underlying mechanisms remain unclear. In this study, we examined the effects of OVX treatment and estradiol (E2) supplementation on formalin-induced nociceptive responses, and explored the associated spinal mechanisms. Female Sprague-Dawley rats underwent bilateral OVX, and E2 supplementation was given subcutaneously from the 5th week after surgery (30 μg/day for 7 days). Our results showed that formalin-induced nociceptive behaviors did not differ between diestrus and proestrus stages of the estrous in intact rats. However, OVX exacerbated formalin-evoked inflammatory pain, especially in the late phase at 4-5 weeks but not 2 weeks post-surgery. E2 supplementation significantly reversed the OVX-triggered hyperalgesia. Double immunofluorescence staining revealed that both ERα and ERβ in the spinal dorsal horn were co-labeled with the neuronal markers, but not with markers of astrocytes or microglia. The spinal ERα (but not ERβ) expression significantly increased in the OVX group, which was reversed by E2 supplementation. Moreover, the OVX individuals showed an increased protein kinase B (AKT) level in lumbar spinal cord, and E2 supplementation diminished the AKT expression in OVX rats. Finally, intrathecal injection Wortmannin, an inhibitor for AKT signaling, effectively reduced the nociceptive behaviors in the late phase and the number of c-fos positive cells. Together, our findings indicate that E2 supplementation alleviates the OVX-induced hyperalgesia, which might be involved in spinal ERα and AKT mechanisms.

Progesterone and its derivatives for the treatment of catamenial epilepsy: A systematic review

OBJECTIVE

Catamenial epilepsy (CE) is defined as an increase in seizure frequency during specific phases of the menstrual cycle in women with epilepsy. The treatment usually includes a combination of non-hormonal and hormonal therapies. This systematic review summarizes the available data on the efficacy of progesterone and its derivates to treat CE.

METHODS

We performed a systematic search of the literature to identify studies reporting data on the use of progesterone and its derivatives (any type and dose) for the treatment of CE. The main outcome included the efficacy of progesterone and its derivatives on seizure frequency.

RESULTS

Nineteen articles (457 patients) were included; four were randomized controlled trials (two comparing progesterone vs placebo and two comparing norethisterone vs placebo). Progesterone was generally administered during the luteal phase (from day 15 to 25) or during perimenstrual exacerbations (from day 23 to 25), with an average dose of 10-30 mg/day to a maximum of 300 mg/day. The therapy, usually well tolerated, was ineffective in the randomized controlled trials; conversely, it was associated with an overall reduction in seizure frequency in case reports and uncontrolled studies.

CONCLUSIONS

Although data from uncontrolled studies suggest that hormone therapy with progesterone may be useful in the treatment of CE, its efficacy has not been demonstrated in controlled trials. The possible antiseizure effect of progesterone could be mediated by its active metabolite allopregnanolone, making the plasmatic measurement of these hormones mandatory to evaluate efficacy. Further randomized controlled trials should investigate the efficacy of progesterone and its derivatives, addressing these pharmacological issues.

[Migraine in women: clinical and therapeutical aspects]

Migraine is one of the most common neurological disorders, affecting women. Physiological changes in the hormonal status can modulate the functional status of pain and analgesic systems of the brain and, by involving different pathophysiological mechanisms, change the course of migraine. In addition to an analysis of epidemiological data, the review provides current views on the clinical features of the disease in women population at different periods of life, particular attention was focused on menstrual migraine. It has certain features, such as acute and long attacks and treatment difficulties. One of main issues is the use of oral contraceptives in women with migraine according to the ratio of potential benefit to cardiovascular risk. The problems of treatment headaches in pregnant and breastfeeding women are also considered. An influence of migraine on the course and outcome of pregnancy was shown. The authors analysed the results of the studies on the course of migraine during perimenopause and postmenopause and recommendations for women with migraine attacks and climacteric syndrome. The data presented in the review are useful for clinicians, because this information represents new views on pathogenetic mechanisms, clinical features and treatment of migraine in women.

Pharmacological Modulation of the Sigma 1 Receptor and the Treatment of Pain

There is a critical need for new analgesics acting through new mechanisms of action, which could increase the efficacy with respect to existing therapies and reduce their unwanted effects. Current preclinical evidence supports the modulatory role of sigma-1 receptors (σ1R) in nociception, mainly based on the pain-attenuated phenotype of σ1R knockout mice and on the antinociceptive effect exerted by σ1R antagonists on pains of different etiologies. σ1R is highly expressed in different pain areas of the CNS and the periphery (particularly dorsal root ganglia), and interacts and modulates the functionality of different receptors and ion channels . The antagonism of σ1R leads to decreased amplification of pain signaling within the spinal cord (central sensitization), but recent data also support a role at the periphery. σ1R antagonists have consistently demonstrated efficacy in neuropathic pain , but also in other types of pain including inflammatory, orofacial, visceral, and post-operative pain. Apart from acting alone, when combined with opioids, σ1R antagonists enhance opioid analgesia but not opioid-induced unwanted effects. Interestingly, unlike opioids, σ1R antagonists do not modify normal sensory mechanical and thermal sensitivity thresholds but they exert antihypersensitive effects in sensitizing conditions, enabling the reversal of nociceptive thresholds back to normal values. Accordingly, σ1R antagonists are not strictly analgesics; they are antiallodynic and antihyperalgesic drugs acting when the system is sensitized following prolonged noxious stimulation or persistent abnormal afferent input (e.g., secondary to nerve injury). These are distinctive features allowing σ1R antagonists to exert a modulatory effect specifically in pathophysiological conditions such as chronic pain .

Purinergic system dysfunction in mood disorders: a key target for developing improved therapeutics

Uric acid and purines (such as adenosine) regulate mood, sleep, activity, appetite, cognition, memory, convulsive threshold, social interaction, drive, and impulsivity. A link between purinergic dysfunction and mood disorders was first proposed a century ago. Interestingly, a recent nationwide population-based study showed elevated risk of gout in subjects with bipolar disorder (BD), and a recent meta-analysis and systematic review of placebo-controlled trials of adjuvant purinergic modulators confirmed their benefits in bipolar mania. Uric acid may modulate energy and activity levels, with higher levels associated with higher energy and BD spectrum. Several recent genetic studies suggest that the purinergic system - particularly the modulation of P1 and P2 receptor subtypes - plays a role in mood disorders, lending credence to this model. Nucleotide concentrations can be measured using brain spectroscopy, and ligands for in vivo positron emission tomography (PET) imaging of adenosine (P1) receptors have been developed, thus allowing potential target engagement studies. This review discusses the key role of the purinergic system in the pathophysiology of mood disorders. Focusing on this promising therapeutic target may lead to the development of therapies with antidepressant, mood stabilization, and cognitive effects.

The second to fourth digit ratio (2D:4D): a risk factor of migraine and tension-type headache

BACKGROUND

Migraine and Tension-type headache (TTH) are common and disabling primary headache disorders. They are more prevalent in females. The second to fourth digit ratio (2D:4D) is sexually dimorphic in humans and is considered to be a marker for the balance of prenatal testosterone and estrogen exposure. Therefore, we investigated the hypothesis that prenatal sex steroids constitute an independent risk factor for adult headaches later in life.

METHODS

A total of 891 individuals (303 males, 588 females) of 18-68 years in age (a mean of 37.0 ± 10.1 years), including 279 migraine, 300 TTH, and 312 healthy subjects were enrolled. The 2D:4D ratio was measured by a single investigator using a digital Vernier caliper.

RESULTS

The females in the migraine group had lower 2D:4D ratios than those in the control group (left hand: 0.947 ± 0.034 vs. 0.955 ± 0.038, p = 0.048; right hand: 0.952 ± 0.035 vs. 0.965 ± 0.037, p = 0.001). There was a similar relationship between the TTH group and the control group (left hand: 0.946 ± 0.034 vs. 0.955 ± 0.038, p = 0.034; right hand: 0.954 ± 0.035 vs. 0.965 ± 0.037, p = 0.005), although this was not observed in males. Males showed lower 2D:4D ratios than females for the right hand in the control group (0.954 ± 0.039 vs. 0.965 ± 0.037, p = 0.015). No significant difference was found in the left hand.

CONCLUSIONS

These results suggested that the 2D:4D ratio is a risk factor of migraine and TTH and that the balance of prenatal estrogen and testosterone in utero may impact adult primary headache disorders.

PSYCHOPHYSIOLOGICAL CHARACTERISTICS OF WOMEN IN DEPENDENCE ON THE OVARIOHORMONAL CYCLE PHASE AND PROGESTERONE ACTIVITY (PART 1)

With the aim to identify the effects of menstrual cycle phase on the cognitive and psycho-emotional characteristics in 78 women aged 18–27 years were studied in a within-subject design Half the subjects began during their follicular phase and half began during their luteal phase (LP). The level of psycho-emotional tension was lowest, but cognitive performance efficiency is a highest in LP that is associated with the highest saliva progesterone level.

Use of Vitex agnus-castus in migrainous women with premenstrual syndrome: an open-label clinical observation

Premenstrual syndrome (PMS) affects most women during their reproductive life. Headache is regarded as a typical symptom of PMS and, close to menses, migrainous women could experience their worst migraine attacks. Vitex agnus-castus (VAC) is a phytopharmaceutical compound, considered worldwide to be a valid tool to treat PMS. Aim of this study is to explore if headache is ameliorate in migrainous women treated with VAC for PMS by an open-label clinical observation. Migrainous women with PMS were enrolled in the study and advised to assume a treatment with VAC (40 mg/day) for PMS for a 3-month period. Effects both on PMS and headache were assessed. Out of 107 women, 100 completed the 3-month treatment for PMS. Out of them, 66 women reported a dramatic reduction of PMS symptoms, 26 a mild reduction, and 8 no effect. Concerning migraine, 42 % of patients experienced a reduction higher than 50 % in frequency of monthly attacks, and 57 % of patients experienced a reduction higher than 50 % in monthly days with headache. No patients reported remarkable side effects. Pending a placebo-controlled trial to confirm our results, we observed that the use of VAC in migrainous women affected by PMS resulted to be safe and well tolerated, and may positively influence the frequency and duration of migraine attacks.

Diagnosis and management of catamenial seizures: a review

Catamenial epilepsy is defined as a pattern of seizures that changes in severity during particular phases of the menstrual cycle, wherein estrogens are proconvulsant, increasing the neuronal excitability; and progesterone is anticonvulsant, enhancing GABA-mediated inhibition. Thus, changes in serum estradiol/progesterone ratio throughout a normal reproductive cycle bring about an increased or decreased risk of seizure occurrence. To date, there are no specific drug treatments for catamenial epilepsy however, non-hormonal and hormonal therapies have been proposed. The aim of this review is to report preclinical and clinical evidences about the relationship between female reproductive steroids and epileptic seizures, and to describe treatment approaches for catamenial epilepsy.

[Gender aspects in anesthesia : modified approach in research and treatment?]

Gender differences can have a relevant influence on the perioperative outcome as male and female patients are affected differently by adverse events, e.g. side effects of drugs. Furthermore, differences relating to specific drug effects, comorbidities and outcome after anesthesia or intensive care have been demonstrated. There seems to be a gender bias in diagnosis and therapy. While the knowledge regarding this field is still growing certain aspects have already been integrated into clinical practice: prevention of postoperative nausea and vomiting (PONV), target controlled infusion (TCI) model and male only policy with production of blood products. There is a need to study the influence of gender, age and race in order to optimize treatment towards a more individualized therapy. This article highlights already identified differences and discusses potential underlying mechanisms.

Hormonal manipulation strategies in the management of menstrual migraine and other hormonally related headaches

Menstrual migraine and other hormonally related headaches are common in women. Falling estrogen levels or estrogen withdrawal after periods of sustained higher levels can trigger migraine. It makes sense to target this trigger for management of hormonally related headaches, particularly when nonhormonal strategies have been unsuccessful. Decision making regarding the use of hormonal contraception and menopausal hormone therapy is complex and commonly driven by other factors, but hormonal manipulation can potentially improve the course of migraine. Providers caring for migraineurs are appropriately concerned about stroke risk. Estrogen-containing hormonal contraceptives are relatively contraindicated for women who have migraine with aura. Postmenopausal hormone therapy is acceptable for women with a history of migraine. For these women, transdermal estradiol is recommended. Estrogen replacement is important for women who undergo an early menopause, whether natural or induced. Practical strategies for hormonal manipulation in the management of migraine and other hormonally related headaches are presented.

Progesterone intoxication inducing marked sedation in a cat

A 3-year-old, male castrated domestic shorthair cat presented for sudden onset of severe lethargy and loss of balance a few hours after potentially ingesting capsules containing progesterone. Elevated serum progesterone was confirmed. Supportive care and time resulted in complete resolution of the clinical signs with no long-term complications or recurrence of clinical signs noticed after 1-month follow-up. This is the first description of progesterone intoxication inducing neurological signs in a cat.

Increased risk of pre-eclampsia (PE) among women with the history of migraine

The Objective of this study was to assess possible association of history of migraine with pre-eclampsia (PE). This was a retrospective study to compare history of migraine in 90 women affected by PE with 90 women without PE as the control group. They recruited by a nonrandomized consecutive sampling method. Data were collected by a questionnaire including demographic, medical, obstetrics, and migraine assessment sections. Data were analyzed using SPSS. Results showed an increased risk of PE in women with history of migraine (odds ratio: 2.87; p < 0.05). Result demonstrated that migraine history in the case group is 14/4% and in control group is 5/6%. Gestational age (GA) at delivery and weight of neonate (WN) were significantly lower compared to control (GA: 37.3 +/- 2.6 vs. 38.7+/- 1.3 weeks T test; P < 0.01) (WN: 2930 +/- 690 vs. 3330 +/- 420; T test; P < 0.0). Cesarean section was more frequent in the PE group compared to the control group [37 (42%) vs. 14 (15.6%)]; chi square; p < 0.01]. The association of migraine with PE is the result of some similar mechanism leading to endothelial dysfunction. Frequent reports of an association between migraine and PE in different populations suggest a history of migraine as a risk factor for PE/gestational hypertension (GH).

Lack of association of hormone receptor polymorphisms with migraine

BACKGROUND AND PURPOSE

Previous studies concerning the role of hormone receptor genetic variants in migraine have provided conflicting results. The aim of this study was to investigate the role of common polymorphisms in the estrogen receptor gene (ESR1) and the progesterone receptor gene (PGR) in the risk for migraine in a Spanish population.

METHODS

In a case-control study, including 210 Caucasoid migraine patients and 210 controls, we examined association between three single nucleotide polymorphisms in the coding region of ESR1, rs2077642, rs1801132, and rs2228480, and an Alu insertion in PGR, and migraine, migraine without aura or migraine with aura. Genotypic, allelic and reconstructed haplotype distributions were compared.

RESULTS

We found no significant differences between cases and controls in the distribution of genotypes or alleles for either polymorphism. No haplotype was over-represented in patients.

CONCLUSIONS

Our study does not support a major contribution of ESR1 and PGR to the pathogenesis of migraine.