Variation of plasma cortisol levels in patients with depression after treatment with bilateral electroconvulsive therapy

Effects of left anodal transcranial direct current stimulation on hypothalamic-pituitary-adrenal axis activity in depression: a randomized controlled pilot trial

The main objective of this study was to evaluate the effect of left anodal transcranial direct current stimulation (tDCS) on hypothalamic-pituitary-adrenal axis (HPAA) activity in individuals with depression. We conducted a 3-week, randomized, triple-blind pilot trial with 47 participants (dropout rate: 14.89%) randomly assigned to either the tDCS or control group (sham stimulation). Salivary cortisol was used as an HPAA activity marker since cortisol is the effector hormone of the HPAA. The primary outcome was the effect of tDCS on the diurnal cortisol pattern (DCP and area under the curve with respect to ground -AUCg-). Secondary outcomes included tDCS effects on cortisol awakening response (CAR) and cortisol decline (CD), as well as the variation of cortisol concentrations between the initiation of tDCS and 2 weeks later. Intention-to-treat and per-protocol analyses were conducted. Our primary outcome showed an absent effect of tDCS on DCP and AUCg. Additionally, tDCS had an absent effect on CAR, CD, and cortisol concentration variation before-after stimulation. Our pilot study suggests that anodal tDCS showed an absent effect on HPAA activity in individuals with depression. More studies are needed to confirm these findings.

Electroconvulsive Therapy in Psychiatric Disorders: A Narrative Review Exploring Neuroendocrine-Immune Therapeutic Mechanisms and Clinical Implications

Electroconvulsive therapy (ECT) is based on conducting an electrical current through the brain to stimulate it and trigger generalized convulsion activity with therapeutic ends. Due to the efficient use of ECT during the last years, interest in the molecular bases involved in its mechanism of action has increased. Therefore, different hypotheses have emerged. In this context, the goal of this review is to describe the neurobiological, endocrine, and immune mechanisms involved in ECT and to detail its clinical efficacy in different psychiatric pathologies. This is a narrative review in which an extensive literature search was performed on the Scopus, Embase, PubMed, ISI Web of Science, and Google Scholar databases from inception to February 2022. The terms "electroconvulsive therapy", "neurobiological effects of electroconvulsive therapy", "molecular mechanisms in electroconvulsive therapy", and "psychiatric disorders" were among the keywords used in the search. The mechanisms of action of ECT include neurobiological function modifications and endocrine and immune changes that take place after ECT. Among these, the decrease in neural network hyperconnectivity, neuroinflammation reduction, neurogenesis promotion, modulation of different monoaminergic systems, and hypothalamus-hypophysis-adrenal and hypothalamus-hypophysis-thyroid axes normalization have been described. The majority of these elements are physiopathological components and therapeutic targets in different mental illnesses. Likewise, the use of ECT has recently expanded, with evidence of its use for other pathologies, such as Parkinson's disease psychosis, malignant neuroleptic syndrome, post-traumatic stress disorder, and obsessive-compulsive disorder. In conclusion, there is sufficient evidence to support the efficacy of ECT in the treatment of different psychiatric disorders, potentially through immune, endocrine, and neurobiological systems.

Lipoic acid prevents mirtazapine-induced weight gain in mice without impairs its antidepressant-like action in a neuroendocrine model of depression

Mirtazapine (MIRT) is a multi-target antidepressant used in treatment of severe depression with promising efficacy, but also with important side effects, mainly sedation and weight gain. Thus, the present study aimed to test the effects of the neuroprotective antioxidant lipoic acid (ALA) in the reversal of weight and metabolic changes induced by MIRT in corticosterone-induced depression model in mice, as well as proposed mechanisms for their association antidepressant and pro-cognitive effects. To do these male Swiss mice received Tween 80 (control), corticosterone (CORT 20 mg / kg), MIRT (3 mg / kg) and ALA (100 or 200 mg / kg), alone or associated for 21 days. After this, the animals were subjected to behavioral tests for affective and cognitive domains. Daily weight changes, blood cholesterol fractions and corticosterone were measured. Also, hippocampus (HC) protein expression of the serotonin transporter (SERT), synaptophysin, protein kinase B-Akt (total and phosphorylated) and the cytokines IL-4 and IL-6 were investigated. CORT induced a marked depression-like behavior, memory deficits, metabolic changes (total cholesterol and LDL) and increased serum corticosterone. Also, CORT increased SERT expression in the HC. MIRT alone or combined with ALA sustained its antidepressant-like effect, as well as reversed CORT-induced impairment in spatial recognition memory. Additionally, the association MIRT+ALA200 reversed the weight gain induced by the former antidepressant, as well as reduced serum corticosterone levels and SERT expression in the HC. ALA alone induced significant weight loss and reduced total cholesterol and HDL fraction. Our findings provide promising evidence about the ALA potential to prevent metabolic and weight changes associated to MIRT, without impair its antidepressant and pro-cognition actions. Therefore, ALA+MIRT combination could represent a new therapeutic strategy for treating depression with less side effects.

Gradient of electro-convulsive therapy's antidepressant effects along the longitudinal hippocampal axis

Despite decades of successful treatment of therapy-resistant depression and major scientific advances in the field, our knowledge about electro-convulsive therapy's (ECT) mechanisms of action is still scarce. Building on strong empirical evidence for ECT-induced hippocampus anatomy changes, we sought to test the hypothesis that ECT has a differential impact along the hippocampus longitudinal axis. We acquired behavioural and brain anatomy magnetic resonance imaging (MRI) data in patients with depressive episode undergoing ECT (n = 9) or pharmacotherapy (n = 24) and healthy controls (n = 30) at two time points 3 months apart. Using whole-brain voxel-based statistical parametric mapping and topographic analysis focused on the hippocampus, we observed ECT-induced gradient of grey matter volume increase along the hippocampal longitudinal axis with predominant impact on its anterior portion. Clinical outcome measures showed strong correlations with both baseline volume and rate of ECT-induced change exclusively for the anterior, but not posterior hippocampus. We interpret our findings confined to the anterior hippocampus and amygdala as additional evidence of the regional specific impact of ECT that unfolds its beneficial effect on depression via the "limbic" system. Main limitations of the study are patients' polypharmacy, heterogeneity of psychiatric diagnosis, and long-time interval between scans.

Ugo Cerletti (1877-1963): An Early Italian Father of Electroshock and a Pioneer in Many Other Ways

This article provides a biographical review of the life and the professional achievements of the Italian doctor Ugo Cerletti and an introduction on electroshock. Throughout his medical career, he travelled and studied in many countries all over the world. Building upon his systematic and comprehensive analysis of mental diseases, Cerletti introduced electroshock, which, at his time, was a novel therapeutic method. The main beneficial feature of electroshock was that it ameliorated refractory mental illnesses such as depression, mania, and schizophrenia. Additionally, Cerletti filmed the first scientific movie on electroshock. Furthermore, Cerletti left great lessons in the area of dementia, by proving the interaction between spirochaetes and progressive paralysis and exploring the causes of inflammation in the syphilitic brain. Cerletti was the first to announce the theory of acroagonines. Cerletti also made early discoveries on perivascular corpuscles, a discovery of such importance that the perivascular corpuscles are named corpuscles of Cerletti. Outside of the medical realm, Cerletti invented a new type of gun, and produced an early medical documentary. Cerletti received many national and international distinctions and awards. He died in 1963 at the age of 86.

Cortisol and Major Depressive Disorder-Translating Findings From Humans to Animal Models and Back

Major depressive disorder (MDD) is a global problem for which current pharmacotherapies are not completely effective. Hypothalamic-pituitary-adrenal (HPA) axis dysfunction has long been associated with MDD; however, the value of assessing cortisol as a biological benchmark of the pathophysiology or treatment of MDD is still debated. In this review, we critically evaluate the relationship between HPA axis dysfunction and cortisol level in relation to MDD subtype, stress, gender and treatment regime, as well as in rodent models. We find that an elevated cortisol response to stress is associated with acute and severe, but not mild or atypical, forms of MDD. Furthermore, the increased incidence of MDD in females is associated with greater cortisol response variability rather than higher baseline levels of cortisol. Despite almost all current MDD treatments influencing cortisol levels, we could find no convincing relationship between cortisol level and therapeutic response in either a clinical or preclinical setting. Thus, we argue that the absolute level of cortisol is unreliable for predicting the efficacy of antidepressant treatment. We propose that future preclinical models should reliably produce exaggerated HPA axis responses to acute or chronic stress a priori, which may, or may not, alter baseline cortisol levels, while also modelling the core symptoms of MDD that can be targeted for reversal. Combining genetic and environmental risk factors in such a model, together with the interrogation of the resultant molecular, cellular, and behavioral changes, promises a new mechanistic understanding of MDD and focused therapeutic strategies.

Electroconvulsive therapy, depression, the immune system and inflammation: A systematic review

BACKGROUND

The management and treatment of major depressive disorder are major public health challenges, the lifetime prevalence of this illness being 4.4%-20% in the general population. Major depressive disorder and treatment resistant depression appear to be, in part, related to a dysfunction of the immune response. Among the treatments for depression ECT occupies an important place. The underlying cerebral mechanisms of ECT remain unclear.

OBJECTIVES/HYPOTHESIS

The aim of this review is to survey the potential actions of ECT on the immuno-inflammatory cascade activated during depression.

METHODS

A systematic search of the literature was carried out, using the bibliographic search engines PubMed and Embase. The search covered articles published up until october 2017. The following MESH terms were used: Electroconvulsive therapy AND (inflammation OR immune OR immunology).

RESULTS

Our review shows that there is an acute immuno-inflammatory response immediately following an ECT session. There is an acute stress reaction. Studies show an increase in the plasma levels of cortisol and of interleukins 1 and 6. However, at the end of the course of treatment, ECT produces, in the long term, a fall in the plasma level of cortisol, a reduction in the levels of TNF alpha and interleukin 6.

LIMITATIONS

One of the limitations of this review is that a large number of studies are relatively old, with small sample sizes and methodological bias.

CONCLUSION

Advances in knowledge of the immuno-inflammatory component of depression seem to be paving the way towards models to explain the mechanism of action of ECT.