5-HT1A responsivity in patients with panic disorder before and after treatment with aerobic exercise, clomipramine or placebo

Cognitive decline prevention in offspring of Pb+2 exposed mice by maternal aerobic training and Cur/CaCO3@Cur supplementations: In vitro and in vivo studies

Heavy metals are considered contaminants that hazardously influence the healthy life of humans and animals as they are widely used in industry. Contact of youngsters and women at ages of parturition with lead (Pb⁺²) is a main related concern, which passes through the placental barricade and its better absorption in the intestine leads to flaws in the fetal developfment. However, the metals threaten animal and human life, in particular throughout developmental stages. Products existing in the nature have a major contribution to innovating chemo-preventives. As a naturally available polyphenol and necessary curcuminoid, curcumin (Cur) is a derivative of the herb Curcuma longa (L.) rhizome, which globally recognized as "wonder drug of life"; however, Cur has a limited clinical use as it is poorly dissolved in water. Therefore, to enhance its clinically relevant parameters, curcumin-loaded calcium carbonate (CaCO₃@Cur) was synthesized by one step coprecipitation method as a newly introduced in this research. Initially, its structure was physio chemically characterized using FT-IR, FESEM and DLS equipment and then the cytotoxicity of lead when it was pretreated with Cur/CaCO₃@Cur were assessed by MTT assay. Both Cur and CaCO₃@Cur diminished the toxic effects of Pb⁺² while the most protective effect on the Pb⁺² cytotoxicity was achieved by pre-incubation of cells with CaCO₃@Cur. Besides, the morphological changes of Pb⁺²-treated cells that were pre-incubated with or without Cur/CaCO₃@Cur were observed by normal and florescent microscopes. A non-pharmacologic method that lowers the hazard of brain damage is exercise training that is capable of both improving and alleviating memory. In the current study, the role of regular aerobic training and CaCO₃@Cur was assessed in reducing the risk of brain damage induced by lead nitrate contact. To achieve the mentioned goal, pregnant Balb/C mice were assigned to five groups (six mice/group) at random: negative and positive controls, aerobic training group and Cur and CaCO₃@Cur treated (50 mg/kg/b.wt) trained groups that exposed to Pb⁺² (2 mg/kg) by drinking water during breeding and pregnancy. With the completion of study, offspring were subjected to the behavioral tasks that was tested by step-through ORT, DLB, MWM and YM tests. As a result, having regular aerobic training and CaCO₃@Cur co-administration with lead nitrate could reverse the most defected behavioral indicators; yet, this was not visible for both sexes and it seems that gender can also be a source of different effects in the animal's body. In fact, having regular aerobic training along with CaCO₃@Cur supplementation during pregnancy may be encouraging protecting potential agents towards the toxicity of Pb⁺² that could be recommended in the areas with high pollution of heavy metals.

Exercise alleviates depression related systemic inflammation in chronic obstructive pulmonary disease patients

BACKGROUND

Depression is a highly prevalent co-morbidity in Chronic Obstructive Pulmonary Disease (COPD) which was shown to be associated with a worse course of disease, including reduced quality of life and increased symptoms burden, healthcare use, and even mortality. It has been speculated that systemic inflammation may play a role in the presence of depression. Currently, physical activity is an important lifestyle factor that has the potential to modify inflammatory cytokines and depression, however our understanding of how to use exercise effectively in COPD patients to alleviate depression related systemic inflammation is incomplete and has prompted our interest to identify the type and intensities of effective exercise.

OBJECTIVE

The aim of this study was to measure the changes in depression related systemic inflammation of aerobic exercise training in COPD patients in Jeddah area.

MATERIAL AND METHODS

Eighty patients with moderate severity of COPD participated in this study and were divided into two groups; the first group received aerobic exercise, whereas the second group received no exercise training for 12 weeks.

RESULTS

The mean values of tumor necrosis factor-alpha (TNF-α), interleukin-4 (IL-4), interleukin-6 (IL-6), C-reactive protein (CRP) and Beck Depression Inventory (BDI) scores were significantly decreased in in group (A) after treatments, but the changes in group (B) were not significant .Also, there were significant differences between mean levels of the investigated parameters in group (A) and group (B) at the end of the study.

CONCLUSION

Aerobic exercise is an effective treatment policy to improve depression related to systemic inflammation in patients with chronic obstructive pulmonary disease.

Exercise as Treatment for Anxiety: Systematic Review and Analysis

BACKGROUND

Exercise has been shown to reduce symptoms of anxiety, but few studies have studied exercise in individuals preselected because of their high anxiety.

PURPOSE

The objective of this study is to review and critically evaluate studies of exercise training in adults with either high levels of anxiety or an anxiety disorder.

METHODS

We conducted a systematic review of randomized clinical trials (RCTs) in which anxious adults were randomized to an exercise or nonexercise control condition. Data were extracted concerning anxiety outcomes and study design. Existing meta-analyses were also reviewed.

RESULTS

Evidence from 12 RCTs suggested benefits of exercise, for select groups, similar to established treatments and greater than placebo. However, most studies had significant methodological limitations, including small sample sizes, concurrent therapies, and inadequate assessment of adherence and fitness levels.

CONCLUSIONS

Exercise may be a useful treatment for anxiety, but lack of data from rigorous, methodologically sound RCTs precludes any definitive conclusions about its effectiveness.

Dissociating the therapeutic effects of environmental enrichment and exercise in a mouse model of anxiety with cognitive impairment

Clinical evidence indicates that serotonin-1A receptor (5-HT1AR) gene polymorphisms are associated with anxiety disorders and deficits in cognition. In animal models, exercise (Ex) and environmental enrichment (EE) can change emotionality-related behaviours, as well as enhance some aspects of cognition and hippocampal neurogenesis. We investigated the effects of Ex and EE (which does not include running wheels) on cognition and anxiety-like behaviours in wild-type (WT) and 5-HT1AR knock-out (KO) mice. Using an algorithm-based classification of search strategies in the Morris water maze, we report for we believe the first time that Ex increased the odds for mice to select more hippocampal-dependent strategies. In the retention probe test, Ex (but not EE) corrected long-term spatial memory deficits displayed by KO mice. In agreement with these findings, only Ex increased hippocampal cell survival and BDNF protein levels. However, only EE (but not Ex) modified anxiety-like behaviours, demonstrating dissociation between improvements in cognition and innate anxiety. EE enhanced hippocampal cell proliferation in WT mice only, suggesting a crucial role for intact serotonergic signalling in mediating this effect. Together, these results demonstrate differential effects of Ex vs EE in a mouse model of anxiety with cognitive impairment. Overall, the 5-HT1AR does not seem to be critical for those behavioural effects to occur. These findings will have implications for our understanding of how Ex and EE enhance experience-dependent plasticity, as well as their differential impacts on anxiety and cognition.

Azapirones versus placebo for panic disorder in adults

BACKGROUND

Panic disorder is common in the general population. It is often associated with other psychiatric disorders, such as drug dependence, major depression, bipolar disorder, social phobia, specific phobia and generalised anxiety disorder. Azapirones are a class of drugs used as anxiolytics. They are associated with less drowsiness, psychomotor impairment, alcohol potentiation and potential for addiction or abuse than benzodiazepines. However, azapirones are not widely used in the treatment of panic disorder and evidence for their efficacy is unclear. It is important to find out if azapirones are effective and acceptable in the treatment of panic disorder.

OBJECTIVES

To assess the effects of azapirones on panic disorder in adults, specifically:1. to determine the efficacy of azapirones in alleviating symptoms of panic disorder, with or without agoraphobia, in comparison with placebo;2. to review the acceptability of azapirones in panic disorder, with or without agoraphobia, in comparison with placebo; and3. to investigate adverse effects of azapirones in panic disorder with or without agoraphobia, including general prevalence of adverse effects, compared with placebo.

SEARCH METHODS

We searched the Cochrane Depression Anxiety and Neurosis Group Trials Specialised Register (CCDANCTR, search date: 10th January 2014), which includes relevant randomised controlled trials from The Cochrane Library (all years), MEDLINE (1950-), EMBASE (1974-), and PsycINFO (1967-).

SELECTION CRITERIA

Randomised controlled trials that compared azapirones with placebo for panic disorder in adults.

DATA COLLECTION AND ANALYSIS

Three review authors independently identified studies, assessed trial quality and extracted data. We contacted study authors for additional information.

MAIN RESULTS

Three studies involving 170 participants compared the azapirone buspirone with placebo. No study provided enough usable information on our primary efficacy outcome (response). For our primary acceptability outcome, moderate-quality evidence indicated that azapirones had lower acceptability than placebo: risk ratio (RR) for dropouts for any reason 2.13 (95% confidence interval (CI) 1.11 to 4.07; 3 studies, 170 participants. Evidence for secondary efficacy outcomes were of low quality. Results on efficacy between azapirone and placebo in terms of agoraphobia (standardised mean difference (SMD) -0.01, 95% CI -0.56 to 0.53; 1 study, 52 participants), general anxiety (mean difference (MD) -2.20, 95% CI -5.45 to 1.06; 2 studies, 115 participants) and depression (MD -1.80, 95% CI -5.60 to 2.00; 1 study, 52 participants) were uncertain. None of the studies provided information for the assessment of allocation concealment or sequence generation. Conflicts of interest were not explicitly expressed. The risk of attrition bias was rated high for all three studies. Information on adverse effects other than dropouts for any reason was insufficient to include in the analyses.

AUTHORS' CONCLUSIONS

The efficacy of azapirones is uncertain due to the lack of meta-analysable data for the primary outcome and low-quality evidence for secondary efficacy outcomes. A small amount of moderate-quality evidence suggested that the acceptability of azapirones for panic disorder was lower than for placebo. However, only trials of one azapirone (namely buspirone) were included in this review; this, combined with the small sample size, limits our conclusions. If further research is to be conducted, studies with larger sample sizes, with different azapirones and with less risk of bias are necessary to draw firm conclusions regarding azapirones for panic disorder.

Serotonergic genes (5-HTT and HTR1A) and separation life events: gene-by-environment interaction for panic disorder

BACKGROUND

The polymorphisms of serotonergic genes (5-HTTLPR and HTR1A rs6295) and separation life events have been studied to find an association with panic disorder, respectively. However, there are no studies that have yet evaluated the interaction effect between serotonergic genes and separation life events for panic disorder.

METHODS

For this study, 194 panic disorder patients and 172 healthy controls were included for genotyping and environmental factor analysis. Separation life events were assessed using the Stressful Life Events Scale and clinical interviews. To evaluate the potential endophenotypes of panic disorder, the Anxiety Sensitivity Index-revised (ASI-R), harm avoidance in the Temperament and Character Inventory (HA), and neuroticism in the Eysenck Personality Questionnaire (neuroticism) scales were administered.

RESULTS

For 5-HTTLPR and HTR1A rs6295, there was no significant main effect of each genotype on panic disorder alone. However, the number of separation life events and their interaction with 5-HTTLPR showed a statistically significant effect on panic disorder. In addition, the interaction between 5-HTTLPR and the number of separation life events significantly affected the HA for potential endophenotypes.

CONCLUSION

This study could suggest the effect of the interaction between 5-HTTLPR and separation life events on panic disorder and its potential endophenotype.

Investigation of cortisol levels in patients with anxiety disorders: a structured review

Anxiety disorders are common and distressing medical conditions, which typically arise in adolescence or early adult life. They can persist for many years, reducing quality of life, limiting academic and occupational achievement, and being responsible for considerable economic pressures. Although a range of psychological and pharmacological treatments are available, their success is often limited, and many patients remain troubled by significant symptom-related disability for long periods. The detailed pathophysiology of each anxiety disorder is not established, and novel treatments that are based solely on current understanding of conventional neurotransmitter function are unlikely to be substantially more effective or better tolerated than current treatments. Investigations of hypothalamo-pituitary axis function across panic disorder, generalized anxiety disorder, specific phobias and social anxiety disorder have produced intriguing findings but not revealed a consistent pattern of endocrine disturbance, perhaps reflecting differences in methodology and the nature and size of the clinical samples. There is a persistent need for large, prospective studies using standardized methods for investigation and data analysis (164 words).

Recent progress in understanding the pathophysiology of post-traumatic stress disorder: implications for targeted pharmacological treatment

Post-traumatic stress disorder (PTSD) is a common and chronic anxiety disorder that can result after exposure to a traumatic event. Though our understanding of the aetiology of PTSD is incomplete, several neurobiological systems have been implicated in the pathophysiology and vulnerability towards developing PTSD after trauma exposure. We aimed to provide a concise review of benchmark findings in important neurobiological systems related to the aetiology and maintenance of PTSD symptomology. Specifically, we discuss functional aetiologies in the noradrenergic, serotonergic, endogenous cannabinoid and opioid systems as well as the hypothalamic-pituitary adrenal (HPA) axis. This article provides a succinct framework to appreciate the current understanding of neurobiological mechanisms related to the pathophysiology of PTSD and how these findings may impact the development of future, targeted pharmacological treatments for this debilitating disorder.

Exercise and physical activity in the therapy of substance use disorders

Exercise and physical activity are constantly gaining attention as adjuvant treatment for substance use disorders, supplementing classical pharmacological and psychotherapeutic approaches. The present work reviews studies addressing the therapeutic effects of exercise in alcohol abuse/dependence, nicotine abuse/dependence, and illicit drug abuse/dependence. In the field of smoking cessation, evidence is strong for exercise as an effective adjuvant treatment, whereas no generalizable and methodologically strong studies have been published for alcohol and drug treatment so far, allowing only preliminary conclusions about the effectiveness of exercise in these disorders. A couple of potential mechanisms are discussed, by which exercise may act as an effective treatment, as well as future directions for studies investigating exercise as a treatment strategy for substance use disorders.

Exercise and severe depression: preliminary results of an add-on study

BACKGROUND

Physical exercise has been extensively researched as a therapeutic option for treatment of major depression.

METHODS

In a randomized controlled trial, we analyze the effects of aerobic physical exercise as an add-on strategy for treatment of severe depressed inpatients. The exercise has a "Dose" of 16.5 kcal/kg/week, three times a week during all the hospitalization.

RESULTS

Our preliminary results show that there is no significant difference in scores of Hamilton in the second week between groups (Mean[SD]=8.2[5.96] × 11.18[5.03], p=0.192). However, there is a significant reduction in Hamilton scores of patients in exercise group at discharge (Mean[SD]=5.93[4.46] × 9.45[3.56], p=0.041). Regarding Quality of Life (QoL), no significant difference were found between groups in the second week in physical domain (Mean[SD]=56.98[8.96] × 54.54[9.18], p=0.511) and psychological domain (Mean[SD]=50.88[13.88] × 42.04[12.42], p=0.106). However, there is a significant difference in psychological domain (Mean[SD]=55.88[9.92] v 41.66[13.04], p=0.004) and a trend but no statistical significance in the physical (Mean[SD]=58.80[9.14] × 52.12[8.70], p=0.07) at discharge.

LIMITATIONS

Many patients receive different treatment strategies, like ECT (1 patient at exercise group × 3 at control group). Other limitation is the small number of participants included until this moment.

CONCLUSION

Our preliminary results suggest that physical exercise could be a feasible and effective add-on strategy for treatment of severe depressed inpatients, improving their depressive symptoms and QoL.

A randomized, controlled trial of aerobic exercise in combination with paroxetine in the treatment of panic disorder

OBJECTIVES

Regular aerobic exercise (running) has been shown to be superior to a pill placebo in the treatment of panic disorder. Combined drug and exercise treatment has not been investigated in randomized controlled studies to date.

METHODS

This is a randomized, 10-week, controlled, parallel group, pilot study. A total of 75 outpatients with panic disorder with or without agoraphobia (DSM-IV and ICD-10) received either (1) exercise plus paroxetine 40 mg/day (n=21), (2) relaxation plus paroxetine (n=17), (3) exercise plus pill placebo (n=20), or (4) relaxation plus pill placebo (n=17). Changes in the Panic and Agoraphobia Scale (P&A), and the Clinical Global Impression Scale (CGI) underwent repeated measure analysis.

RESULTS

Effects sizes were large for all groups (d=1.53-3.87), however not significantly different. Paroxetine-treated patients were significantly more improved than placebo-treated patients. On the CGI, patients in the exercise groups (plus paroxetine or placebo) had a trend toward better improvement compared to relaxation (P=0.06). Response and remission rates were higher in the paroxetine compared to pill placebo groups.

CONCLUSIONS

While paroxetine was superior to placebo, aerobic exercise did not differ from relaxation training in most efficacy measures.

Panic disorder and serotonergic genes (SLC6A4, HTR1A and HTR2A): Association and interaction with childhood trauma and parenting

OBJECTIVE

The aim of this study is to evaluate the association between HTR1A, HTR2A and the 5-HTTLPR in panic disorder (PD) patients and controls. In addition, this study also aims to evaluate the interaction between these genes and two environmental factors previously associated with PD: childhood trauma and parental bonding.

METHODS

This is a case-control candidate gene association study (107 PD patients and 125 controls). Genes were analyzed using a gene-based test in PLINK followed by single marker association tests and haplotype test only for genes that reached experiment-wide significance in the gene-based test in order to minimize multiple testing. Logistic regression was used to test the relationships between genotype in the additive model, trauma, optimal paternal parenting and optimal maternal parenting and their interactions.

RESULTS

Only HTR1A was associated with PD in gene-based test after correction for multiple tests (p(corrected)=0.027) and one HTR1A haplotype comprising four SNPs was associated with PD (p(corrected)=0.032). In the interaction analysis, no significant gene-environment interaction was found with the genes evaluated.

CONCLUSION

This study reinforces the association between HTR1A and PD. No major evidence of gene-environment interaction in PD with parenting or trauma was found. Further studies are necessary in order to confirm these findings.

Growth hormone, prolactin and cortisol response to exercise in patients with depression

BACKGROUND

A blunted growth hormone and prolactin response to pharmacological stress test have previously been found in depressed patients, as well as an increased cortisol response to psychosocial stress. This study investigated these hormones in response to acute exercise using an incremental bicycle test.

METHOD

A cross-sectional comparison of cortisol, growth hormone, and prolactin in depressed (n=137) and healthy (n=44) subjects during rest and in response to an incremental bicycle test. Secondly, we tested the depressed patients again after a 4-month randomized naturalistic exercise intervention.

RESULTS

Resting plasma levels of growth hormone (GH), cortisol, or prolactin (PRL) did not differ between depressed and healthy subjects (all p-values>.12). In response to an incremental bicycle test the GH (p=.02) and cortisol (p=.05) response in depressed was different compared to healthy controls. The effect of acute exercise stress on PRL (p=.56) did not differ between depressed and healthy subjects. Apart from a decrease in GH response in the strength-training group (p=.03) the pragmatic exercise intervention did not affect resting hormonal levels, or the response to acute exercise.

CONCLUSIONS

Patients with mild to moderate depression had a different growth hormone and cortisol response to acute exercise stress compared to healthy controls. Strength training was able to reduce the growth hormone response to acute exercise stress in this patient population. Studies with more rigorous inclusion criteria and higher exercise frequencies are needed to evaluate and confirm the possible effect of exercise in depressed subjects.

Hormonal responses to the 5-HT1A agonist buspirone in remitted endogenous depressive patients after long-term imipramine treatment

INTRODUCTION

The serotonin-1A (5-HT1A) receptor subtypes are considered as targets of a variety of antidepressant drugs. Previous studies have suggested different adaptive changes in pre- and post-synaptic 5-HT receptors in the brain after treatment with non-selective tricyclic antidepressants (TCA) and selective 5-HT re-uptake inhibitors (SSRIs). The present study aimed to investigate the adaptive effect of the TCA imipramine on the post-synaptic 5-HT1A receptor function in the hypothalamus.

METHODS

A longitudinal design was used in 14 patients with major depressive disorder (DSM-IV) with endogenous features (Newcastle Scale) in order to assess the functional status of post-synaptic 5-HT1A receptors before and after successful antidepressant treatment with imipramine. The effect of the 5-HT1A receptor agonist, buspirone, on ACTH, cortisol, and prolactine (PRL) plasma levels was used to assess the functional status of hypothalamic 5-HT1A receptors. A group of 15 concurrent normal subjects were used as control.

RESULTS

Endogenous depressed patients in remission and currently receiving treatment with imipramine (mean length of treatment 145 days, SD=27) presented significantly lower buspirone responses to ACTH and cortisol than in the pre-treatment condition (Deltamax p< or =.05; AUC p<.001) and to ACTH in comparison with healthy controls (Deltamax p<.01; AUC p<.05). No significant differences were found between the post-treatment and pre-treatment PRL responses, or between patients in both conditions and controls; nevertheless, the PRL response in patients in remission and receiving treatment almost reached the values seen in controls.

CONCLUSIONS

This study extends previous findings from our group using the SSRI citalopram as an antidepressant. Imipramine and citalopram induce similar changes in the endocrine response to buspirone in depressed patients. As the direction of change in ACTH-cortisol and PRL responses after treatment is the opposite, we cannot substantiate increases or decreases in the sensitivity of post-synaptic 5-HT1A receptors in the hypothalamus by long-term imipramine treatment and/or resolution of illness. Therefore, the hormonal changes may result from different or multiples unknown mechanisms.

The serotonin-1A receptor in anxiety disorders

The serotonin system plays an important role in the neural processing of anxiety. The involvement of the main inhibitory serotonergic receptor, the serotonin-1A (5-HT1A) subtype, in dysfunctional forms of anxiety has been supported by findings from a wide range of preclinical research and clinical trials, including treatment studies, genetic research, and neuroimaging data. The following article summarizes preclinical results with a focus on 5-HT1A receptor knockout and transgenic mice as genetic models of anxiety. Behavioral, autonomic, and endocrinological changes in these mice are reported. This article also presents genetic polymorphisms in humans associated with increased anxiety scores and pharmacological data focused on 5-HT1A receptor agonists and antagonists. Furthermore, molecular neuroimaging results are presented. Recent positron emission tomography (PET) studies have reported reduced 5-HT1A receptor binding in patients with panic disorder and social anxiety disorder, but not in posttraumatic stress disorder. In healthy subjects, increased anxiety scores might be associated with lower 5-HT1A receptor binding. This overview of preclinical and clinical data provides strong evidence for the key role of the 5-HT1A receptor in the serotonergic dysregulation of anxiety disorders.

Translational aspects of pharmacological research into anxiety disorders: the stress-induced hyperthermia (SIH) paradigm

In anxiety research, the search for models with sufficient clinical predictive validity to support the translation of animal studies on anxiolytic drugs to clinical research is often challenging. This review describes the stress-induced hyperthermia (SIH) paradigm, a model that studies the activation of the autonomic nervous system in response to stress by measuring body temperature. The reproducible and robust SIH response, combined with ease of testing, make the SIH paradigm very suitable for drug screening. We will review the current knowledge on the neurobiology of the SIH response, discuss the role of GABA(A) and serotonin (5-HT) pharmacology, as well as how the SIH response relates to infectious fever. Furthermore, we will present novel data on the SIH response variance across different mice and their sensitivity to anxiolytic drugs. The SIH response is an autonomic stress response that can be successfully studied at the level of its physiology, pharmacology, neurobiology and genetics and possesses excellent animal-to-human translational properties.

Comparative oxidative metabolic profiles of clomipramine in cats, rats and dogs: preliminary results from an in vitro study

The objectives of this in vitro study were to describe cytochrome-dependent metabolism of clomipramine in canine and feline microsomes, compare metabolic profiles between cats, rats and dogs, and investigate a potential gender-related difference in metabolic activity between male and female cats. Pooled liver microsomes were incubated with clomipramine, where species and gender-specific reactions were initiated by the addition of a nicotinamide adenine dinucleotide phosphate regenerating system and quenched with methanol at 0, 5, 15, 30, 45 and 60 min, and 0, 30, 60, 90, 120, 180, 240 and 360 min respectively. Liquid chromatography tandem mass spectrometry was used to measure clomipramine and its metabolites. Preliminary results showed that cat microsomes biotransformed clomipramine slower and less efficiently than rat and dog microsomes. Moreover, gender differences in metabolic profiles suggested that male cat microsomes may be less efficient demethylators and hydroxylators than female cat microsomes. As gender metabolic differences may carry clinical significance for this antidepressant, further studies are warranted.

Effects of citalopram treatment on hypothermic and hormonal responses to the 5-HT1A receptor agonist buspirone in patients with major depression and therapeutic response

Serotonin (5-HT) 5-HT1A receptor seems to play an important role in the pathophysiology of major depression and in the mechanism of action of antidepressants. In vivo function of 5-HT1A receptors can be monitored using specific pharmacological challenge tests. The present study aimed at exploring the adaptative 5-HT1A receptor changes in depressed patients before and after 8 week treatment with citalopram. The study population consisted of 30 consecutive outpatients of both sexes aged 18-45 years with major depressive disorders (DSM-IV). Basal score in the Hamilton Rating Scale for Depression (HRSD) was higher than 17. Therapeutic response was defined as a 50% decrease in the HRSD score. The hypothermic and endocrine responses (ACTH, cortisol, and prolactin) induced by the 5-HT1A receptor agonist, buspirone (30 mg p.o.) were measured. After 8 weeks on citalopram, the delta max of hypothermic response elicited by buspirone was markedly decreased (p<0.001). Patients showed a decrease in responses to ACTH (delta max p=0.005; AUC p=0.028) and cortisol (delta max p=0.05). However, the prolactin response increased (delta max p=0.02; AUC p=0.005). There was a significant correlation between the therapeutic effect and reductions of ACTH (r=0.883; p<0.001) and cortisol (r=0.610; p=0.001) responses. Changes induced by citalopram support an alteration of 5-HT1A receptors in major depression. A decrease in the overactivity of the HPA axis may be one factor associated with the response to citalopram.

Transtornos de ansiedade e exercício físico

OBJETIVO: A maioria dos estudos sobre os efeitos ansiolíticos do exercício físico, até meados da década de 90, foram realizados avaliando-se estados de ansiedade, com indivíduos jovens, universitários ou atletas, que podem ser considerados pré-condicionados, limitando a validade das conclusões para populações com ansiedade patológica. Na atualidade, o número de estudos envolvendo pacientes com transtorno de ansiedade aumentou. O presente estudo tem por objetivo a revisão de artigos que discutem a influência do exercício físico nos transtornos de ansiedade. MÉTODO: Foi realizada uma pesquisa no Medline, no período de 1966-1995 e 1996-2006, utilizando-se os descritores: anxiety, panic, phobic disorders, exercise, physical fitness, além de referências cruzadas dos artigos selecionados e análise adicional de referências na literatura específica do tema. RESULTADOS: Os achados demonstraram desenhos heterogêneos assim como limitações metodológicas. As publicações mais recentes são promissoras e acenam para a utilização de exercícios físicos aeróbios como auxiliares das terapêuticas tradicionais no tratamento dos transtornos de ansiedade. CONCLUSÃO: Verificou-se que os exercícios aeróbios cuja intensidade não ultrapasse o limiar de lactato podem ser os mais apropriados, mas ainda não esclarecem as implicações dos exercícios anaeróbios, sugerindo cautela na prescrição de exercícios para indivíduos com ansiedade patológica, principalmente em relação aos exercícios anaeróbios.

Interaction of serotonergic and noradrenergic gene variants in panic disorder

OBJECTIVE

Panic disorder is an anxiety disorder with an estimated heritability of 48%. Associations findings have been obtained with candidate genes from both serotonergic and noradrenergic pathways including regulatory and coding variants of the serotonin receptor 1A gene, the monoamine oxidase A gene, the catechol-O-methyltransferase gene and the norepinephrine transporter gene.

METHODS

In the present study, an analysis of interactions between the functional serotonin receptor 1A polymorphism, the norepinephrine transporter variants and the other respective polymorphisms of the above-mentioned genes is reported. The analysis is based on genotype results from 115 cases and 115 age and sex-matched controls.

RESULTS

A nominally significant (P=0.04) interaction between the serotonin receptor 1A and the catechol-O-methyltransferase polymorphisms was observed. Stratified analysis revealed that the odds ratio of each polymorphism was highest in the presence of the low-risk genotype(s) of the other polymorphism and low in the presence of the high-risk genotype(s) of the other polymorphism.

CONCLUSIONS

This is the first possible interaction of genetic variations in panic disorder that has been observed. As the sample size was small and no adjustment for multiple testing was made, the assessment of the interacting risk alleles needs replication in a larger sample with higher power.

Serotonin function in panic disorder: important, but why?

The essential role of serotonin (5-hydroxytryptamine (5-HT)) system in the neurobiology and pharmacotherapy of panic disorder (PD) continues to be a topic of intensive interdisciplinary research. Interest in the involvement of 5-HT in PD has been fuelled by clinical studies demonstrating that medications increasing the synaptic availability of 5-HT, such as selective 5-HT re-uptake inhibitors, are effective in the treatment of PD. Rival theories of 5-HT deficiency vs excess have attempted to explain the impact of 5-HT function in PD. In the past decade, knowledge of the role of 5-HT in the neurobiology of PD has expanded dramatically due to much new research including experimental, treatment, brain-imaging, and genetic studies. The current review attempts to summarize the new data and their implications. The challenge and treatment studies generally confirm the specific inhibitory influence of 5-HT on panicogenesis. The brain-imaging studies in PD patients demonstrate functional and clinically relevant alterations in various elements of 5-HT system affecting the neurocircuitry of panic. The findings of genetic association studies suggest that certain 5-HT-related genes may contribute to the susceptibility to PD; however, these data are rather limited and inconsistent. It appears that, even if not the primary etiological factor in PD, the 5-HT function conveys important vulnerability, as well as adaptive factors. A better understanding of these processes may be critical in achieving progress in the treatment of patients suffering from PD.

The effects of chronic treadmill and wheel running on behavior in rats

In order to better understand the behavioral adaptations induced by physical activity, this set of experiments assessed the effects of two modes of running exercise on a battery of behavioral tests. The effects of 8 weeks of forced treadmill running and voluntary wheel running on behavior measures in the elevated plus maze, open field, social interaction and conditioned freezing paradigms were investigated. Eight weeks of treadmill running did not alter behavior in any test paradigm. Rats given unrestricted access to running wheels (WR) had a lower percent open arm time (6.0+/-2.3%) compared to locked wheel controls (LC) (20.7+/-5.7%) in the elevated plus maze. WR also showed decreased entries into center (0.2+/-0.2) and crossed fewer lines (61.0+/-14.9) in the open field compared to control groups. Both WR and LC groups showed increased social interaction; however, these differences are attributed to housing conditions. The effects of 4 weeks of wheel running on elevated plus maze and open field behavior were also investigated to address the possibility of a temporal effect of exercise on behavior. Four weeks of wheel running produced behavioral changes in the open field similar to those found at 8 weeks, but not in the elevated plus maze suggesting a temporal effect of wheel running on plus maze behavior. The behavioral adaptations found after 4 and 8 weeks of wheel running were not due solely to enriched environment and appear to be indicative of enhanced defensive behavior.