Different Endocrine Effects of an Evening Dose of Amitriptyline, Escitalopram, and Placebo in Healthy Participants

Prolactin and oxytocin: potential targets for migraine treatment

Migraine is a severe neurovascular disorder of which the pathophysiology is not yet fully understood. Besides the role of inflammatory mediators that interact with the trigeminovascular system, cyclic fluctuations in sex steroid hormones are involved in the sex dimorphism of migraine attacks. In addition, the pituitary-derived hormone prolactin and the hypothalamic neuropeptide oxytocin have been reported to play a modulating role in migraine and contribute to its sex-dependent differences. The current narrative review explores the relationship between these two hormones and the pathophysiology of migraine. We describe the physiological role of prolactin and oxytocin, its relationship to migraine and pain, and potential therapies targeting these hormones or their receptors.In summary, oxytocin and prolactin are involved in nociception in opposite ways. Both operate at peripheral and central levels, however, prolactin has a pronociceptive effect, while oxytocin appears to have an antinociceptive effect. Therefore, migraine treatment targeting prolactin should aim to block its effects using prolactin receptor antagonists or monoclonal antibodies specifically acting at migraine-pain related structures. This action should be local in order to avoid a decrease in prolactin levels throughout the body and associated adverse effects. In contrast, treatment targeting oxytocin should enhance its signalling and antinociceptive effects, for example using intranasal administration of oxytocin, or possibly other oxytocin receptor agonists. Interestingly, the prolactin receptor and oxytocin receptor are co-localized with estrogen receptors as well as calcitonin gene-related peptide and its receptor, providing a positive perspective on the possibilities for an adequate pharmacological treatment of these nociceptive pathways. Nevertheless, many questions remain to be answered. More particularly, there is insufficient data on the role of sex hormones in men and the correct dosing according to sex differences, hormonal changes and comorbidities. The above remains a major challenge for future development.

Association between Dissociative Symptoms and Morning Cortisol Levels in Patients with Post-traumatic Stress Disorder

Objective

Patients with post-traumatic stress disorder (PTSD) showed inconsistencies in their cortisol level, an index of the hypothalamic-pituitary-adrenal axis function. This study examined the relationship between dissociation, childhood trauma, and morning cortisol levels in PTSD patients.

Methods

This study included 69 (23 males and 46 females) patients and 82 (22 males and 60 females) healthy controls (HCs). Clinical assessments, including the Childhood Trauma Questionnaire (CTQ) and Peri-traumatic Dissociative Experiences Questionnaire scores, and morning cortisol levels were evaluated. The morning cortisol levels were compared between PTSD with high dissociation and low dissociation (PTSD-LD) groups. The effect of CTQ subtype on morning cortisol levels was analyzed.

Results

The PTSD with high dissociation group showed significantly lower cortisol levels than that of the PTSD-LD and HC groups. A significant inverse correlation was found between cortisol levels and dissociation. A significant positive correlation was found between dissociation and physical abuse and sexual abuse scores. Morning cortisol levels showed a significant positive correlation with emotional abuse, emotional neglect, and physical neglect, respectively. There was no moderating or mediating effect of CTQ on the relationship between cortisol level and dissociation.

Conclusion

These findings suggest that dissociation is a significant factor related to hypocortisolism in PTSD patients. Additionally, basal morning cortisol levels and dissociation scores were closely associated with childhood trauma.

A review of the antimicrobial side of antidepressants and its putative implications on the gut microbiome

OBJECTIVE

Serotonin reuptake inhibitors are the predominant treatment for major depressive disorder. In recent years, the diversity of the gut microbiota has emerged to play a significant role in the occurrence of major depressive disorder and other mood and anxiety disorders. Importantly, the role of the gut microbiota in the treatment of such disorders remains to be elucidated. Here, we provide a review of the literature regarding the effects of physiologically relevant concentrations of serotonin reuptake inhibitors on the gut microbiota and the implications this might have on their efficacy in the treatment of mood disorders.

METHODS

First, an estimation of gut serotonin reuptake inhibitor concentrations was computed based on pharmacokinetic and gastrointestinal transit properties of serotonin reuptake inhibitors. Literature regarding the in vivo and in vitro antimicrobial properties of serotonin reuptake inhibitors was gathered, and the estimated gut concentrations were examined in the context of these data. Computer-based investigation revealed putative mechanisms for the antimicrobial effects of serotonin reuptake inhibitors.

RESULTS

In vivo evidence using animal models shows an antimicrobial effect of serotonin reuptake inhibitors on the gut microbiota. Examination of the estimated physiological concentrations of serotonin reuptake inhibitors in the gastrointestinal tract collected from in vitro studies suggests that the microbial community of both the small intestine and the colon are exposed to serotonin reuptake inhibitors for at least 4 hours per day at concentrations that are likely to exert an antimicrobial effect. The potential mechanisms of the effect of serotonin reuptake inhibitors on the gut microbiota were postulated to include inhibition of efflux pumps and/or amino acid transporters.

CONCLUSION

This review raises important issues regarding the role that gut microbiota play in the treatment of mood-related behaviours, which holds substantial potential clinical outcomes for patients suffering from major depressive disorder and other mood-related disorders.