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Rationale: Current psychotropic medications have been shown to modulate immune activation. However, the effects of individual psychotropic agents on the immune system and how these might contribute to their efficacy remain largely unclear. Objective: This paper aims to review previous literature on the effects of antidepressants and antipsychotics on the immune system, with a systematic review of in vitro findings, and discuss the relevance of these effects for the response to treatment and future drug development. Results: Inflammatory markers have been associated with fluctuations in clinical status and with treatment response both in depression and psychosis. The in vitro literature on antidepressants shows that some antidepressants, such as clomipramine and fluoxetine, more consistently decrease pro-inflammatory cytokines (interleukin (IL)-6, interferon (IFN)-γ, tumour necrosis factor (TNF)-α), whilst others (mirtazapine and venlafaxine) tend to increase their levels. However, any overall conclusion is challenged by several inconsistent findings, which appear partly dependent on different methodological approaches used. The in vitro studies on antipsychotics are even less clear-cut showing pro- and anti-inflammatory activity for the same antipsychotic agent (haloperidol, clozapine, risperidone) across different studies. We also noted inconsistencies between in vivo and in vitro literature, which could partly be attributed to the interaction in vivo with various biological systems or lifestyle factors that can modulate the immune system. Conclusions: Inflammatory markers seem to hold potential for developing more individualised treatment strategies in the future. In this context, further research disentangling the differential immunomodulatory effects of different drugs could be used for tailoring treatment to specific individuals, according to their immune endophenotypes. [ABSTRACT FROM AUTHOR]

Rationale: There is an urgent need to identify behaviours in animals that can provide insight into the aetiology and potential treatment of depression in humans. Objectives: This study aimed to validate a repeated measures cognitive affective bias (CAB) test in a rat model of chronic stress and compare CAB with forced swim test (FST) measures. Methods: Male and female Sprague Dawley rats were trained to associate large and small rewards with scent, spatial, and tactile cues, and their response to an ambiguous tactile stimulus tested. Rats underwent weekly CAB testing for 4 weeks with no intervention, or for 2 weeks of chronic restraint stress (CRS), followed by 2 weeks of fluoxetine, vehicle, or no treatment. CRS rats also underwent the FST at selected timepoints. Results: In control rats, CAB was positive and remained stable over the 4-week period. In CRS-fluoxetine and CRS-vehicle groups, CAB was initially positive, became negative during chronic restraint stress, and returned to positive by 2 weeks after treatment. However, in the CRS-no treatment group, CAB was variable at the outset and unstable over time. Behaviour in the FST was not affected by treatment, and there was no correlation between CAB and FST outcomes. Conclusions: Instability in the CRS-no treatment group precluded interpretation of the impact of fluoxetine on CAB post-CRS. Our results suggest that behaviour in the FST does not reflect or alter affective state and support the use of CAB tests as part of the behavioural testing repertoire for preclinical animal models of affective disorders. [ABSTRACT FROM AUTHOR]

Amisulpride is approved for clinical use in treating schizophrenia in a number of European countries and also for treating dysthymia, a mild form of depression, in Italy. Amisulpride has also been demonstrated to be an antidepressant for patients with major depression in many clinical trials. In part because of the selective D2/D3 receptor antagonist properties of amisulpride, it has long been widely assumed that dopaminergic modulation is the proximal event responsible for mediating its antidepressant and antipsychotic properties. The purpose of these studies was to determine if amisulpride’s antidepressant actions are mediated by off-target interactions with other receptors. We performed experiments that: (1) examined the pharmacological profile of amisulpride at a large number of central nervous system (CNS) molecular targets and, (2) after finding high potency antagonist affinity for human 5-HT7a serotonin receptors, characterized the actions of amisulpride as an antidepressant in wild-type and 5-HT7 receptor knockout mice. We discovered that amisulpride was a potent competitive antagonist at 5-HT7a receptors and that interactions with no other molecular target investigated in this paper could explain its antidepressant actions in vivo . Significantly, and in contrast to their wild-type littermates, 5-HT7 receptor knockout mice did not respond to amisulpride in two widely used rodent models of depression, the tail suspension test and the forced swim test. These results indicate that 5-HT7a receptor antagonism, and not D2/D3 receptor antagonism, likely underlies the antidepressant actions of amisulpride. [ABSTRACT FROM AUTHOR]

Pharmacogenetic studies in mood disorders are raising increasing interest, after the first findings of a significant association between antidepressant response and a functional polymorphism in the upstream regulatory region of the serotonin transporter gene (SERTPR). However, the results of published studies are not unequivocal. The reasons of these discordances could be various: the small samples, which could affect the power to detect a good effect size, the use of different and often not comparable scales and methodologies to assess the response rates. Notwithstanding all these limitations, the choice of candidate genes involved in antidepressant response is one of the crucial steps to target future research. In the present paper, we reviewed the literature concerning pharmacogenetic studies on antidepressant response. This analysis evidenced a number of studies consistently confirming the association of the SERTPR short variant with a poorer response to antidepressants, at least for the Caucasian samples. Further unreplicated positive findings included tryptophan hydroxylase (TPH), G-protein beta3-subunit (Gbeta3) and serotonin receptor 2A gene polymorphisms. Through the review, we also suggested possible candidate genes for future studies, which are involved in the main monoaminergic neurotransmitters pathways (norepinephrine, dopamine, serotonin), in substance P, neurokinines and glutamate systems, in the intracellular signal transduction pathway, in the phosphorylation process and in the control of the transcriptional activity system. [ABSTRACT FROM AUTHOR]

The effects of four serotonin (5-HT)-1A compounds (buspirone, gepirone, ipsapirone and zalospirone) were compared with 5-hydroxytryptophan (5-HTP) [a 5-HT precursor with antidepressant (AD) efficacy], and diazepam (a benzodiazepine anxiolytic), on a differential-reinforcement-of-low-rate 72-s (DRL 72-s) schedule. Past research has shown that AD and anxiolytic compounds each have distinct effects on the DRL 72-s interresponse time (IRT) distribution profile. In the present paper, the profile of the IRT distribution was quantitatively characterized by three metrics: burst ratio, peak location and peak area. 5-HTP shifted the IRT distribution peak toward longer IRT durations, increased reinforcement rate and decreased response rate. The profile of the IRT distribution was not disrupted by 5-HTP. Diazepam disrupted the IRT distribution and increased bursting. In general, the arylpiperazine, 5-HT compounds increased reinforcement rate, decreased response rate and disrupted the profile of the IRT distribution. The effects of the four arylpiperazine 5-HT compounds on the IRT distribution profile were different from the AD profile of 5-HTP and the benzodiazepine anxiolytic profile of diazepam. Disruption of the IRT distribution by buspirone, gepirone, ipsapirone and zalospirone may result from decreased 5-HT transmission mediated by the presynaptic, somatodendritic 5-HT receptor. [ABSTRACT FROM AUTHOR]

Rationale: Preclinical studies indicate that high-frequency oscillations, above 100 Hz (HFO:100–170 Hz), are a potential translatable biomarker for pharmacological studies, with the rapid acting antidepressant ketamine increasing both gamma (40–100 Hz) and HFO. Objectives: To assess the effect of the uncompetitive NMDA antagonist ketamine, and of D-cycloserine (DCS), which acts at the glycine site on NMDA receptors on HFO in humans. Methods: We carried out a partially double-blind, 4-way crossover study in 24 healthy male volunteers. Each participant received an oral tablet and an intravenous infusion on each of four study days. The oral treatment was either DCS (250 mg or 1000 mg) or placebo. The infusion contained 0.5 mg/kg ketamine or saline placebo. The four study conditions were therefore placebo-placebo, 250 mg DCS-placebo, 1000 mg DCS-placebo, or placebo-ketamine. Results: Compared with placebo, frontal midline HFO magnitude was increased by ketamine (p = 0.00014) and 1000 mg DCS (p = 0.013). Frontal gamma magnitude was also increased by both these treatments. However, at a midline parietal location, only HFO were increased by DCS, and not gamma, whilst ketamine increased both gamma and HFO at this location. Ketamine induced psychomimetic effects, as measured by the PSI scale, whereas DCS did not increase the total PSI score. The perceptual distortion subscale scores correlated with the posterior low gamma to frontal high beta ratio. Conclusions: Our results suggest that, at high doses, a partial NMDA agonist (DCS) has similar effects on fast neural oscillations as an NMDA antagonist (ketamine). As HFO were induced without psychomimetic effects, they may prove a useful drug development target. [ABSTRACT FROM AUTHOR]

Rationale: Reward-related impairments are common in major depressive disorder (MDD) and may contribute to the loss of interest in pleasurable activities. A novel approach to studying reward-related decision-making are effort-based tasks; however, direct comparisons between delayed-onset and rapid-acting antidepressants (ADs) have not yet been carried out. Objectives: To investigate the effects of conventional delayed-onset ADs versus rapid-acting ADs, ketamine and scopolamine, on effort-related choice behaviour. Methods: Female Lister hooded rats were trained in an operant effort for reward task (EfRT) where animals choose between working for a high value-high effort reward and consuming low value-low effort chow. Using a within-subject study design, animals were then tested following acute treatment with different monoaminergic ADs, and the rapid-acting ADs ketamine or scopolamine. Results: Consistent with previous findings, we found choice behaviour was sensitive to dopaminergic manipulations. We observed that pre-feeding altered choice behaviour and that the use of high or low value reward differentially affected behaviour. Monoamine re-uptake inhibitors and rapid-acting ADs resulted in similar, general patterns of reduced motivation without any evidence for specific effects, and we did not observe any clear differences between these classes of antidepressant. Conclusions: Motivational changes induced by dopaminergic manipulations and pre-feeding differentially affect effort choice behaviour. However, both conventional delayed-onset ADs and ketamine and scopolamine appear to have detrimental effects on motivation in this task at the higher doses tested without any evidence of specificity for effort-related choice behaviour, in contrast to their specificity in tasks which look at more cognitive aspects of reward processing. [ABSTRACT FROM AUTHOR]

Rationale: Dysregulation of the one carbon cycle is documented in depression. Thereby, S-adenosylmethionine (SAMe), a one–carbon cycle nutraceutical compound with a favourable side effect profile, has a theoretical rationale for efficacy. However, further controlled studies are required to confirm SAMe's efficacy. Objectives: To test the efficacy of SAMe versus placebo in unmedicated DSM-5 diagnosed (major depressive disorder) (MDD) patients with mild-to-moderate levels of depressive symptoms. Methods: We conducted an 8-week, double-blind, randomised controlled trial testing 800 mg/day of SAMe monotherapy versus placebo in 49 patients with MDD (Montgomery-Åsberg Depression Rating Scale [MADRS] score 14–25) who were not currently taking antidepressants. One–carbon cycle biomarkers, brain-derived neurotropic factor (BDNF), and relevant single nucleotide polymorphisms (SNPs) were analysed as potential treatment moderators. Results: A clinically relevant differential reduction from baseline to week 8 of 3.76 points occurred on the primary outcome (MADRS) in favour of SAMe. This however was not significant (p = 0.13) on an adjusted linear mixed model, notwithstanding a medium to large effect size of 0.72. A high placebo response rate of 53% occurred (> 50% reduction on MADRS). Exploratory analyses showed that SAMe was however effective in reducing depression amongst participants with milder depression severity (MADRS ≤ 22, p = 0.045). Response was not moderated by BDNF, SNPs, or one–carbon cycle biomarkers, although increased folate concentrations were correlated with improved symptoms in the SAMe group (r = − 0.57, p = 0.026). The treatment was safe and well tolerated. Conclusions: Although a differential reduction in depression symptoms between groups was observed in favour of SAMe, the results of this pilot study were not statistically significant. Trial registration: ANZCTR—Australian New Zealand Clinical Trials Registry; No.: ACTRN12613001299796; URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=364900 [ABSTRACT FROM AUTHOR]

Rationale: Androgen deprivation therapy (ADT) is an effective treatment for prostate cancer, but induces profound cognitive impairment. Little research has addressed mechanisms underlying these deficits or potential treatments. This is an unmet need to improve quality of life for prostate cancer survivors. Objectives: We investigated mechanisms of cognitive impairment after ADT in rats and potential utility of the multimodal serotonin-targeting drug, vortioxetine, to improve the impairment, as vortioxetine has specific efficacy against cognitive impairment in depression. Methods: Male Sprague-Dawley rats were surgically castrated. Vortioxetine (28 mg/kg/day) was administered in the diet. The attentional set-shifting test was used to assess medial prefrontal cortex (mPFC) executive function. Afferent-evoked field potentials were recorded in the mPFC of anesthetized rats after stimulating the ventral hippocampus (vHipp) or medial dorsal thalamus (MDT). Gene expression changes were assessed by microarray. Effects of vortioxetine on growth of prostate cancer cells were assessed in vitro. Results: ADT impaired cognitive set shifting and attenuated responses evoked in the mPFC by the vHipp afferent, but not the MDT. Both the cognitive impairment and attenuated vHipp-evoked responses were reversed by chronic vortioxetine treatment. Preliminary investigation of gene expression in the mPFC indicates that factors involved in neuronal plasticity and synaptic transmission were down-regulated by castration and up-regulated by vortioxetine in castrated animals. Vortioxetine neither altered the growth of prostate cancer cells in vitro nor interfered with the antiproliferative effects of the androgen antagonist, enzalutamide. Conclusions: These results suggest that vortioxetine may be useful in mitigating cognitive impairment associated with ADT for prostate cancer. [ABSTRACT FROM AUTHOR]

The human gut contains trillions of symbiotic bacteria that play a key role in programming different aspects of host physiology in health and disease. Psychotropic medications act on the central nervous system (CNS) and are used in the treatment of various psychiatric disorders. There is increasing emphasis on the bidirectional interaction between drugs and the gut microbiome. An expanding body of evidence supports the notion that microbes can metabolise drugs and vice versa drugs can modify the gut microbiota composition. In this review, we will first give a comprehensive introduction about this bidirectional interaction, then we will take into consideration different classes of psychotropics including antipsychotics, antidepressants, antianxiety drugs, anticonvulsants/mood stabilisers, opioid analgesics, drugs of abuse, alcohol, nicotine and xanthines. The varying effects of these widely used medications on microorganisms are becoming apparent from in vivo and in vitro studies. This has important implications for the future of psychopharmacology pipelines that will routinely need to consider the host microbiome during drug discovery and development. [ABSTRACT FROM AUTHOR]

Despite decades of clinical use and research, the mechanism of action (MOA) of antidepressant medications remains poorly understood. Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are the most commonly prescribed antidepressants—atypical antidepressants such as bupropion have also proven effective, while exhibiting a divergent clinical phenotype. The difference in phenotypic profiles presumably lies in the differences among the MOAs of SSRIs/SNRIs and bupropion. We integrated the ensemble of bupropion’s affinities for all its receptors with the expression levels of those targets in nervous system tissues. This “combined target tissue” profile of bupropion was compared to those of duloxetine, fluoxetine, and venlafaxine to isolate the unique target tissue effects of bupropion. Our results suggest that the three monoamines—serotonin, norepinephrine, and dopamine—all contribute to the common antidepressant effects of SSRIs, SNRIs, and bupropion. At the same time, bupropion is unique in its action on 5-HT3AR in the dorsal root ganglion and nicotinic acetylcholine receptors in the pineal gland. These unique tissue-specific activities may explain unique therapeutic effects of bupropion, such as pain management and smoking cessation, and, given melatonin’s association with nicotinic acetylcholine receptors and depression, highlight the underappreciated role of the melatonergic system in bupropion’s MOA. [ABSTRACT FROM AUTHOR]

Rationale: It has recently been found that chronic treatment with the highly selective, brain-penetrating Y5 receptor antagonist, Lu AA33810 [N-[[trans-4-[(4,5-dihydro [1] benzothiepino[5,4-d] thiazol-2-yl) amino] cyclohexyl]methyl]-methanesulfonamide], produces antidepressant-like effects in the rat chronic mild stress model. Objective: In the present study, we investigated the possible antidepressant-like activity of Lu AA33810 in rats subjected to glial ablation in the prefrontal cortex (PFC) by the gliotoxin L-AAA, which is an astroglial degeneration model of depression. Results: We observed that Lu AA33810 administered intraperitoneally at a single dose of 10 mg/kg both reversed depressive-like behavioral changes in the forced swim test (FST) and prevented degeneration of astrocytes in the mPFC. The mechanism of antidepressant and glioprotective effects of Lu AA33810 has not been studied, so far. We demonstrated the contribution of the noradrenergic rather than the serotonergic pathway to the antidepressant-like action of Lu AA33810 in the FST. Moreover, we found that antidepressant-like effect of Lu AA33810 was connected with the influence on brain-derived neurotrophic factor (BDNF) protein expression. We also demonstrated the antidepressant-like effect of Lu AA33810 in the FST in rats which did not receive the gliotoxin. We found that intracerebroventricular injection of the selective MAPK/ERK inhibitor U0126 (5 μg/2 μl) and the selective PI3K inhibitor LY294002 (10 nmol/2 μl) significantly inhibited the anti-immobility effect of Lu AA33810 in the FST in rats, suggesting that MAPK/ERK and PI3K signaling pathways could be involved in the antidepressant-like effect of Lu AA33810. Conclusion: Our results indicate that Lu AA33810 exerts an antidepressant-like effect and suggest the Y5 receptors as a promising target for antidepressant therapy. [ABSTRACT FROM AUTHOR]

Rationale: Affective biases seemingly play a crucial role for the onset and development of depression. Acute treatment with monoamine-based antidepressants positively influences emotional processing, and an early correction of biases likely results in repeated positive experiences that ultimately lead to improved mood. Objectives: Using two conventional antidepressants, sertraline and duloxetine, we aimed to forward the characterization of a newly developed affective bias test (ABT) for rats. Further, we examined the effect of vortioxetine, a recently approved antidepressant, and the α adrenoceptor antagonist idazoxan on affective biases. Methods: Sprague Dawley rats were tested in an affective bias test using a fully balanced within-subject study design. Rats learned to associate two different digging substrates with a reward during six reward-pairing days. The absolute value of the rewards was identical, but the affective state at the time of learning induces a positive or negative bias towards the treatment-paired digging substrate at recall. The choice bias between the two digging substrates at recall represents the affective bias. Sertraline (1, 3 and 10 mg/kg), duloxetine (1, 3 and 10 mg/kg), vortioxetine (1, 3 and 10 mg/kg) and idazoxan (3 and 10 mg/kg) were tested in the ABT. Results and conclusions: All four drugs, regardless of their mechanism of action, induced a positive affective bias in the ABT, although the overall effect of treatment was not statistically significant for sertraline and duloxetine. The largest effects were induced by vortioxetine and idazoxan, both of which caused significant positive biases at all tested doses. [ABSTRACT FROM AUTHOR]

Rationale: Metabolic syndrome (MetS) is common in patients with bipolar disorder, with a relative risk of 1.6-2 compared to the general population. The increased risk is believed to be due to unhealthy lifestyles and use of medications. Although antipsychotics and mood stabilizers have been associated with weight gain and MetS, the impact of antidepressants has not been comprehensively evaluated. Objective: The objective of the study is to assess the risk of MetS in patients exposed to different types of antidepressants. Methods: In this cross-sectional study, 294 patients with bipolar disorder were consecutively recruited. MetS was diagnosed according to NCEP ATP-III modified criteria. Antidepressants used by the patients were classified according to the usual nomenclature (SSRI, TCA, SNRI, and other antidepressants) and a pharmacodynamic classification taking into account histamine 1-receptor (H1-R) affinity. Results: Use of antidepressants in general was not associated with MetS (prevalence ratio [PR], 1.08; 95% confidence interval, 0.73 to 1.62; p = 0.70). However, subjects using H1-R high-affinity antidepressants ( N = 15) showed a substantial increase in the prevalence of MetS (PR, 2.17; 95 % confidence interval, 1.24 to 3.80; p = 0.007). When we included the inhibition constant (Ki) as a continuous covariate in the models, we found an inverse association between Ki and prevalence of MetS ( p = 0.004). Conclusion: We observed for the first time in a clinical setting that a pharmacodynamic-based classification of antidepressants could be more useful than the traditional one to predict the risk of MetS in patients with bipolar disorder. Clinical consequences may be relevant. However larger studies are warranted to generalize these results. [ABSTRACT FROM AUTHOR]

Background: Resistance to antidepressant drug treatment remains a major health problem. Animal models of depression are efficient in detecting effective treatments but have done little to increase the reach of antidepressant drugs. This may be because most animal models of depression target the reversal of stress-induced behavioural change, whereas treatment-resistant depression is typically associated with risk factors that predispose to the precipitation of depressive episodes by relatively low levels of stress. Therefore, the search for treatments for resistant depression may require models that incorporate predisposing factors leading to heightened stress responsiveness. Method: Using a diathesis-stress framework, we review developmental, genetic and genomic models against four criteria: (i) increased sensitivity to stress precipitation of a depressive behavioural phenotype, (ii) resistance to chronic treatment with conventional antidepressants, (iii) a good response to novel modes of antidepressant treatment (e.g. ketamine; deep brain stimulation) that are reported to be effective in treatment-resistant depression and (iv) a parallel to a known clinical risk factor. Results: We identify 18 models that may have some potential. All require further validation. Currently, the most promising are the Wistar-Kyoto (WKY) and congenital learned helplessness (cLH) rat strains, the high anxiety behaviour (HAB) mouse strain and the CB1 receptor knockout and OCT2 null mutant mouse strains. Conclusion: Further development is needed to validate models of antidepressant resistance that are fit for purpose. The criteria used in this review may provide a helpful framework to guide research in this area. [ABSTRACT FROM AUTHOR]

Rationale: Successive negative contrast (SNC) describes a change in the behaviour of an animal following a downshift in the quantitative or qualitative value of an expected reward. This behavioural response has been hypothesised to be linked to affective state, with negative states associated with larger and/or prolonged shifts in behaviour. Objective: This study has investigated whether different psychopharmacological treatments have dissociable actions on the SNC effect in rats and related these findings to their actions on different neurotransmitter systems and affective state. Methods: Animals were trained to perform a nose-poke response to obtain a high-value food reward (four pellets). SNC was quantified during devalue sessions in which the reward was reduced to one pellet. Using a within-subject study design, the effects of acute treatment with anxiolytic, anxiogenic, antidepressant and dopaminergic drugs were investigated during both baseline (four pellets) or devalue sessions (one pellet). Results: The indirect dopamine agonist, amphetamine, attenuated the SNC effect whilst the D1/D2 antagonist, alpha-flupenthixol, potentiated it. The antidepressant citalopram, anxiolytic buspirone and anxiogenic FG7142 had no specific effects on SNC, although FG7142 induced general impairments at higher doses. The α-adrenoceptor antagonist, yohimbine, increased premature responding but had no specific effect on SNC. Results for the anxiolytic diazepam were mixed with one group showing an attenuation of the SNC effect whilst the other showed no effect. Conclusions: These data suggest that the SNC effect is mediated, at least in part, by dopamine signalling. The SNC effect may also be attenuated by benzodiazepine anxiolytics. [ABSTRACT FROM AUTHOR]

Rationale: Cytochrome P450 enzymes are important in the metabolism of antidepressants. The highly polymorphic nature of these enzymes has been linked to variability in antidepressant metabolism rates, leading to hope regarding the use of P450 genotyping to guide treatment. However, evidence that P450 genotypic differences underlie the variation in treatment outcomes is inconclusive. Objectives: We explored the links between both P450 genotype and serum concentrations of antidepressant with antidepressant side effects, using data from the Genome-Based Therapeutic Drugs for Depression Project (GENDEP), which is a large ( n = 868), pharmacogenetic study of depressed individuals treated with escitalopram or nortriptyline. Methods: Patients were genotyped for the enzymes CYP2C19 and CYP2D6, and serum concentrations of both antidepressant and primary metabolite were measured after 8 weeks of treatment. Side effects were assessed weekly. We investigated associations between P450 genotypes, serum concentrations of antidepressants and side effects, as well as the relationship between P450 genotype and study discontinuation. Results: P450 genotype did not predict total side effect burden (nortriptyline: n = 251, p = 0.5638, β = −0.133, standard error (SE) = 0.229; escitalopram: n = 340, p = 0.9627, β = −0.004, SE = 0.085), study discontinuation (nortriptyline n = 284, hazard ratio (HR) = 1.300, p = 0.174; escitalopram n = 376, HR = 0.870, p = 0.118) or specific side effects. Serum concentrations of antidepressant were only related to a minority of the specific side effects measured: dry mouth, dizziness and diarrhoea. Conclusions: In this sample where antidepressant dosage is titrated using clinical judgement, P450 genotypes do not explain differences between patients in side effects with antidepressants. Serum drug concentrations appear to only explain variability in the occurrence of a minority of specific side effects. [ABSTRACT FROM AUTHOR]

Rationale: Gender may influence antidepressant (AD) treatment outcome. In order to address this preclinically, the potential effects of ovarian hormones on AD treatment in ovariectomized female rats were investigated. Objectives: In the first study, the effect of acute administration of estrogen and progesterone on the antidepressant-like effects of desipramine (DMI), a selective norepinephrine reuptake inhibitor (SNRI), was investigated in the forced swimming test (FST). In the second study, the effect of chronic administration of these hormones on the effects of chronically administered DMI was investigated. Results: In the acute study, the hormones blocked the effects of DMI in the FST as demonstrated by the absence of either a reduction in immobility or an increase in climbing behavior in animals treated with DMI in combination with the hormones. Concentration-response experiments on hippocampal synaptosomes revealed no changes in the Km or Bmax for uptake of H-NE in hormone-treated rats. In the chronic study, the antidepressant-like effects of DMI in the FST were not blocked by chronic administration of hormones. Interestingly, the hormones affected the serum concentrations of DMI. These levels were significantly higher in animals receiving 10 or 15 mg/kg/day in hormone-treated rats as compared to those with placebo. Conclusions: Acute administration of hormones blocked the effects of DMI (given three times over 24 h) in the FST. However, chronic administration of these hormones failed to block the effects of chronically administered DMI (at a dose that produces clinically relevant serum concentrations). [ABSTRACT FROM AUTHOR]

Rationale and objective: Hypericum perforatum (St John's wort) is used to treat depression, but the effectiveness has not been established. Recent guidelines described the analysis of clinical trials with missing data, inspiring the reanalysis of this trial using proper missing data methods. The objective was to determine whether hypericum was superior to placebo in treating major depression. Methods: A placebo-controlled, randomized clinical trial was conducted for 8 weeks to determine the effectiveness of hypericum or sertraline in reducing depression, measured using the Hamilton depression scale. We performed sensitivity analyses under different assumptions about the missing data process. Results: Three hundred forty participants were randomized, with 28 % lost to follow-up. The missing data mechanism was not missing completely at random. Under missing at random assumptions, some sensitivity analyses found no difference between either treatment arm and placebo, while some sensitivity analyses found a significant difference from baseline to week 8 between sertraline and placebo (−1.28, 95 % credible interval [−2.48; −0.08]), but not between hypericum and placebo (0.56, [−0.64;1.76]). The results were similar when the missing data process was assumed to be missing not at random. Conclusions: There is no difference between hypericum and placebo, regardless of the assumption about the missing data process. There is a significant difference between sertraline and placebo with some statistical methods used. It is important to conduct an analysis that takes account of missing data using valid statistically principled methods. The assumptions about the missing data process could influence the results. [ABSTRACT FROM AUTHOR]