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OBJECTIVE: Recent evidence shows that during slow-wave sleep (SWS), the brain is cleared from potentially toxic metabolites, such as the amyloid-beta protein. Poor sleep or elevated cortisol levels can worsen amyloid-beta clearance, potentially leading to the formation of amyloid plaques, a neuropathological hallmark of Alzheimer disease. Here, we explored how nocturnal neural and endocrine activity affects amyloid-beta fluctuations in the peripheral blood. METHODS: We acquired simultaneous polysomnography and all-night blood sampling in 60 healthy volunteers aged 20-68 years. Nocturnal plasma concentrations of amyloid-beta-40, amyloid-beta-42, cortisol, and growth hormone were assessed every 20 minutes. Amyloid-beta fluctuations were modeled with sleep stages, (non)oscillatory power, and hormones as predictors while controlling for age and participant-specific random effects. RESULTS: Amyloid-beta-40 and amyloid-beta-42 levels correlated positively with growth hormone concentrations, SWS proportion, and slow-wave (0.3-4Hz) oscillatory and high-band (30-48Hz) nonoscillatory power, but negatively with cortisol concentrations and rapid eye movement sleep (REM) proportion measured 40-100 minutes previously (all t values > |3|, p values < 0.003). Older participants showed higher amyloid-beta-40 levels. INTERPRETATION: Slow-wave oscillations are associated with higher plasma amyloid-beta levels, whereas REM sleep is related to decreased amyloid-beta plasma levels, possibly representing changes in central amyloid-beta production or clearance. Strong associations between cortisol, growth hormone, and amyloid-beta presumably reflect the sleep-regulating role of the corresponding releasing hormones. A positive association between age and amyloid-beta-40 may indicate that peripheral clearance becomes less efficient with age. ANN NEUROL 2024;96:46-60.
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Peptídeos beta-Amiloides , Polissonografia , Sono REM , Sono de Ondas Lentas , Humanos , Pessoa de Meia-Idade , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/metabolismo , Adulto , Masculino , Idoso , Feminino , Sono de Ondas Lentas/fisiologia , Adulto Jovem , Sono REM/fisiologia , Hidrocortisona/sangue , Fragmentos de Peptídeos/sangueRESUMO
STUDY OBJECTIVES: Voluntary sleep restriction is a common phenomenon in industrialized societies aiming to increase time spent awake and thus productivity. We explored how restricting sleep to a radically polyphasic schedule affects neural, cognitive, and endocrine characteristics. METHODS: Ten young healthy participants were restricted to one 20-minute nap opportunity at the end of every 4 hours (i.e. six sleep episodes per 24 hours) without any extended core sleep window, which resulted in a cumulative sleep amount of just 2 hours per day (i.e. ~20 minutes per bout). RESULTS: All but one participant terminated this schedule during the first month. The remaining participant (a 25-year-old male) succeeded in adhering to a polyphasic schedule for five out of the eight planned weeks. Cognitive and psychiatric measures showed modest changes during polyphasic as compared to monophasic sleep, while in-blood cortisol or melatonin release patterns and amounts were apparently unaltered. In contrast, growth hormone release was almost entirely abolished (>95% decrease), with the residual release showing a considerably changed polyphasic secretional pattern. CONCLUSIONS: Even though the study was initiated by volunteers with exceptional intrinsic motivation and commitment, none of them could tolerate the intended 8 weeks of the polyphasic schedule. Considering the decreased vigilance, abolished growth hormone release, and neurophysiological sleep changes observed, it is doubtful that radically polyphasic sleep schedules can subserve the different functions of sleep to a sufficient degree.
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Hormônio do Crescimento Humano , Masculino , Humanos , Adulto , Polissonografia , Sono/fisiologia , Vigília/fisiologia , Hormônio do CrescimentoRESUMO
Objective: Aiming at revising the therapeutic reference range for olanzapine, the present study highlights the association between blood olanzapine levels, clinical effects, and dopamine D2-receptor occupancy for oral and long-acting injectable (LAI) formulations.Data Sources: Databases were systematically searched for randomized controlled trials (RCTs) and uncontrolled trials concerning blood olanzapine levels in relation to clinical outcomes or D2-receptor occupancy using MEDLINE (PubMed), Web of Science, PsycINFO, and Cochrane Library (March 2021, updated in December 2021). We excluded articles not written in English or German and non-human data. Search terms included olanzapine, blood level, drug monitoring, PET, and SPECT.Study Selection: The process of study selection followed a previously published protocol and PRISMA guidelines. A total of 2,824 articles were identified through database search and 1 article via reference list check. Thirty-four studies were suitable for qualitative synthesis, and 13 studies were included in the quantitative analysis.Data Extraction: Reviewers performed data extraction and quality assessment of the included studies independently following the review protocol.Results: Evidence for a relationship between blood olanzapine level and efficacy/side effects (constipation) is considered low (Level C). In total, 3 studies of moderate quality consistently showed therapeutic thresholds of around 20 ng/mL for olanzapine 12 hours post-dose. This threshold is in line with findings from positron emission tomography (PET) studies that suggest optimal drug efficacy (65%-80% D2-receptor occupancy) between 17 and 44 ng/mL.Conclusions: We suggest a therapeutic reference range of 20-40 ng/mL for olanzapine oral and LAI formulations. In this range, optimal treatment response is expected in patients with schizophrenia and schizophrenia spectrum disorders. Side effects, especially weight gain, may already occur at therapeutic levels. However, higher plasma concentrations are in general well tolerated and should not necessarily require a dose reduction in case of good response and tolerance.
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Antipsicóticos , Esquizofrenia , Humanos , Olanzapina/uso terapêutico , Antipsicóticos/efeitos adversos , Valores de Referência , Esquizofrenia/tratamento farmacológico , Esquizofrenia/induzido quimicamente , Receptores de Dopamina D2 , Benzodiazepinas/efeitos adversosRESUMO
BACKGROUND: Chemotherapy-induced neuropathic pain (CIPN) describes a pathological pain state that occurs dose-dependently as a side effect and can limit or even impede an effective cancer therapy. Unfortunately, current treatment possibilities for CIPN are remarkably confined and mostly inadequate as CIPN therapeutics themselves consist of low effectiveness and may induce severe side effects, pointing out CIPN as pathological entity with an emerging need for novel treatment targets. Here, we investigated whether the novel and highly specific FKBP51 inhibitor SAFit2 reduces paclitaxel-induced neuropathic pain. METHODS: In this study, we used a well-established multiple low-dose paclitaxel model to investigate analgesic and anti-inflammatory properties of SAFit2. For this purpose, the behavior of the mice was recorded over 14 days and the mouse tissue was then analyzed using biochemical methods. RESULTS: Here, we show that SAFit2 is capable to reduce paclitaxel-induced mechanical hypersensitivity in mice. In addition, we detected that SAFit2 shifts lipid levels in nervous tissue toward an anti-inflammatory and pro-resolving lipid profile that counteracts peripheral sensitization after paclitaxel treatment. Furthermore, SAFit2 reduced the activation of astrocytes and microglia in the spinal cord as well as the levels of pain-mediating chemokines. Its treatment also increased anti-inflammatory cytokines levels in neuronal tissues, ultimately leading to a resolution of neuroinflammation. CONCLUSIONS: In summary, SAFit2 shows antihyperalgesic properties as it ameliorates paclitaxel-induced neuropathic pain by reducing peripheral sensitization and resolving neuroinflammation. Therefore, we consider SAFit2 as a potential novel drug candidate for the treatment of paclitaxel-induced neuropathic pain.
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Neuralgia , Paclitaxel , Camundongos , Animais , Paclitaxel/toxicidade , Doenças Neuroinflamatórias , Gliose/induzido quimicamente , Gliose/tratamento farmacológico , Neuralgia/induzido quimicamente , Neuralgia/tratamento farmacológico , Neuralgia/prevenção & controle , Lipídeos/efeitos adversosRESUMO
Introduction: In recent years, purinergic signaling via the P2X7 receptor (P2X7R) on microglia has repeatedly been implicated in depression genesis. However, it remains unclear which role the human P2X7R (hP2X7R) plays in regulating both microglia morphology and cytokine secretion upon different environmental and immune stimuli, respectively. Methods: For this purpose, we used primary microglial cultures derived from a humanized microglia-specific conditional P2X7R knockout mouse line to emulate different gene-environment interactions between microglial hP2X7R and molecular proxies of psychosocial and pathogen-derived immune stimuli. Microglial cultures were subjected to treatments with the agonists 2'(3')-O-(4-benzoylbenzoyl)-ATP (BzATP) and lipopolysaccharides (LPS) combined with specific P2X7R antagonists (JNJ-47965567, A-804598). Results: Morphotyping revealed overall high baseline activation due to the in vitro conditions. Both BzATP and LPS + BzATP treatment increased round/ameboid microglia and decreased polarized and ramified morphotypes. This effect was stronger in hP2X7R-proficient (CTRL) compared to knockout (KO) microglia. Aptly, we found antagonism with JNJ-4796556 and A-804598 to reduce round/ameboid microglia and increase complex morphologies only in CTRL but not KO microglia. Single cell shape descriptor analysis confirmed the morphotyping results. Compared to KO microglia, hP2X7R-targeted stimulation in CTRLs led to a more pronounced increase in microglial roundness and circularity along with an overall higher decrease in aspect ratio and shape complexity. JNJ-4796556 and A-804598, on the other hand, led to opposite dynamics. In KO microglia, similar trends were observed, yet the magnitude of responses was much smaller. Parallel assessment of 10 cytokines demonstrated the proinflammatory properties of hP2X7R. Following LPS + BzATP stimulation, IL-1ß, IL-6, and TNFα levels were found to be higher and IL-4 levels lower in CTRL than in KO cultures. Vice versa, hP2X7R antagonists reduced proinflammatory cytokine levels and increased IL-4 secretion. Discussion: Taken together, our results help disentangle the complex function of microglial hP2X7R downstream of various immune stimuli. In addition, this is the first study in a humanized, microglia-specific in vitro model identifying a so far unknown potential link between microglial hP2X7R function and IL-27 levels.
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Treatment with mirtazapine, a widely prescribed antidepressant, has been linked to weight gain and dyslipidemia. Whether dyslipidemia occurs secondary to increased appetite due to antidepressant treatment, or due to direct pharmacological effects of mirtazapine is unknown. The aim of this analysis is to complement our previously published results of the effect of mirtazapine on metabolism and energy substrate partitioning from a proof-of-concept, open-label clinical study (ClinicalTrials.gov NCT00878540) in 12 healthy males (20-25 years). We report the effect of a seven-day administration of mirtazapine 30 mg per day on weight and lipid metabolism in healthy men under highly standardized conditions with respect to diet, physical activity and day-night-rhythm and under continuous clinical observation. After a 7-day administration of mirtazapine 30 mg, we observed a statistically significant increase in triglyceride levels (mean change + 4.4 mg/dl; 95% CI [- 11.4; 2.6]; p = 0.044) as well as TG/HDL-C ratio (mean change + 0.2; 95% CI [- 0.4; 0.1]; p = 0.019) and a decrease in HDL-cholesterol (mean change - 4.3 mg/dl; 95% CI [2.1; 6.5]; p = 0.004), LDL-cholesterol (mean change - 8.7 mg/dl; 95% CI [3.8; 13.5]; p = 0.008), total cholesterol (mean change - 12.3 mg/dl; 95% CI [5.4; 19.1]; p = 0.005), and non-HDL-C (mean change - 8.0 mg/dl; 95% CI [1.9; 14.0]; p = 0.023). Notably, weight (mean change - 0.6 kg; 95% CI [0.4; 0.8]; p = 0.002) and BMI (mean change - 0.2; 95% CI [0.1; 0.2]; p = 0.002) significantly decreased. No change in waist circumference (mean change - 0.4 cm; 95% CI [- 2.1; 2.9]; p = 0.838) or waist-to-hip-ratio (mean change 0.0; 95% CI [- 0.0; 0.0]; p = 0.814) was observed. This is the first study showing unfavorable changes in lipid metabolism under mirtazapine in healthy individuals despite highly standardized conditions including dietary restriction, and despite the observation of a decrease of weight. Our findings support the hypothesis that mirtazapine has direct pharmacological effects on lipid metabolism. ClinicalTrials.gov: NCT00878540.
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Antidepressivos , Dislipidemias , Humanos , Masculino , HDL-Colesterol , Jejum , Mirtazapina , Triglicerídeos , Aumento de PesoRESUMO
Importance: Insufficient treatment response and resulting chronicity constitute a major problem in depressive disorders. Remission rates range as low as 15% to 40% and treatment-resistant depression (TRD) is associated with low-grade inflammation, suggesting anti-inflammatory interventions as a rational treatment strategy. Minocycline, which inhibits microglial activation, represents a promising repurposing candidate in the treatment of TRD. Objective: To determine whether 6 weeks of minocycline as add-on to antidepressant treatment as usual can significantly reduce depressive symptoms in patients with TRD. Design, Setting, and Participants: The study was conducted in Germany and designed as a multicenter double-blind randomized clinical trial (RCT) of 200 mg/d minocycline treatment over a course of 6 weeks with a 6-month follow-up. Participants were recruited from January 2016 to August 2020 at 9 university hospitals that served as study sites. Key inclusion criteria were a diagnosis of major depressive disorder (according to Diagnostic and Statistical Manual of Mental Disorders [Fifth Edition] criteria), severity of depressive symptoms on the Hamilton Depression Rating Scale (HAMD-17) greater than or equal to 16 points, aged 18 to 75 years, body mass index 18 to 40, Clinical Global Impression Scale (CGI-S) greater than or equal to 4, failure to adequately respond to an initial antidepressant standard medication as per Massachusetts General Hospital Antidepressant Treatment History Questionnaire, and stable medication for at least 2 weeks. A total of 258 patients were screened, of whom 173 were randomized and 168 were included into the intention-to-treat population. Statistical analysis was performed from April to November 2020. Interventions: Participants were randomized (1:1) to receive adjunct minocycline (200 mg/d) or placebo for 6 weeks. Main Outcomes and Measures: Primary outcome measure was the change in Montgomery-Åsberg Depression Rating Scale (MADRS) score from baseline to week 6 analyzed by intention-to-treat mixed model repeated measures. Secondary outcome measures were response, remission, and various other clinical rating scales. Results: Of 173 eligible and randomized participants (84 randomized to minocycline and 89 randomized to placebo), 168 formed the intention-to-treat sample (79 [47.0%] were women, 89 [53.0%] were men, 159 [94.6%] were White, 9 [6.4%] were of other race and ethnicity, including Asian and unknown ethnicity), with 81 in the minocycline group and 87 in the placebo group. The mean (SD) age was 46.1 (13.1) years, and the mean (SD) MADRS score at baseline was 26.5 (5.0). There was no difference in rates of completion between the minocycline (83.3% [70 of 81]) and the placebo group (83.1% [74 of 87]). Minocycline treatment did not alter the course of depression severity compared with placebo as assessed by a decrease in MADRS scores over 6 weeks of treatment (1.46 [-1.04 to 3.96], P = .25). Minocycline treatment also exhibited no statistically significant effect on secondary outcomes. Conclusions and Relevance: In this large randomized clinical trial with minocycline at a dose of 200 mg/d added to antidepressant treatment as usual for 6 weeks, minocycline was well tolerated but not superior to placebo in reducing depressive symptoms in patients with TRD. The results of this RCT emphasize the unmet need for therapeutic approaches and predictive biomarkers in TRD. Trial Registration: EU Clinical Trials Register Number: EudraCT 2015-001456-29.
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Transtorno Depressivo Resistente a Tratamento , Minociclina , Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Método Duplo-Cego , Feminino , Humanos , Masculino , Minociclina/efeitos adversos , Minociclina/uso terapêuticoRESUMO
More than 700,000 people worldwide die by suicide every year, and the number of suicide attempts is estimated as 20 times higher, most of them being associated with psychiatric disorders, especially major depression. Knowledge about effective methods for preventing suicide attempts in individuals at high risk for suicide is still scarce. Dysregulation of the neuroendocrine stress response system, i.e., the hypothalamic-pituitary-adrenocortical (HPA) axis, is one of the most consistent neurobiological findings in both major depression and suicidality. While the HPA axis is mostly overactive in depression, individuals with a history of suicide attempts exhibit an attenuated hormonal response to stress. It is unknown, however, whether the HPA axis is constantly attenuated in repeated suicide attempters or whether it regains normal responsivity after recovery from depression. Using the combined dexamethasone suppression/corticotropin-releasing hormone (dex/CRH) test, we assessed HPA axis regulation in acute depression (N = 237) and after recovery with respect to previous suicide attempts. Patients without previous suicide attempts show normalization of the stress hormone response to the second dex/CRH (basal ACTH response and cortisol response) after recovery from acute depression, while patients with multiple previous SA show an increased ACTH response. The change in HPA axis responsivity in patients with only one previous SA lies between the response patterns of the other groups with no change in HPA axis reactivity. Our findings suggest that patients with a history of suicide attempts belong to a subgroup of individuals that exhibit a distinct pattern of stress hormone response during acute depression and after recovery. Future studies may extend our approach by investigating additional psychological stress tasks to gain a broader understanding of the stress pathology of recurrent suicide attempters.
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INTRODUCTION: Pharmacogenetic testing is proposed to minimize adverse effects when considered in combination with pharmacological knowledge of the drug. As yet, limited studies in clinical settings have investigated the predictive value of pharmacokinetic (pk) gene variation on therapeutic drug levels as a probable mechanism of adverse effects, nor considered the combined effect of pk gene variation and drug level on antidepressant treatment response. METHODS: Two depression cohorts were investigated for the relationship between pk gene variation and antidepressant serum concentrations of amitriptyline, venlafaxine, mirtazapine and quetiapine, as well as treatment response. For the analysis, 519 patients (49% females; 46.6±14.1 years) were included. RESULTS: Serum concentration of amitriptyline was associated with CYP2D6 (higher concentrations in poor metabolizers compared to normal metabolizers), of venlafaxine with CYP2C19 (higher concentrations in intermediate metabolizers compared to rapid/ultrarapid metabolizers) and CYP2D6 (lower metabolite-to-parent ratio in poor compared to intermediate and normal metabolizers, and intermediate compared to normal and ultrarapid metabolizers). Pk gene variation did not affect treatment response. DISCUSSION: The present data support previous recommendations to reduce starting doses of amitriptyline and to guide dose-adjustments via therapeutic drug monitoring in CYP2D6 poor metabolizers. In addition, we propose including CYP2C19 in routine testing in venlafaxine-treated patients to improve therapy by raising awareness of the risk of low serum concentrations in CYP2C19 rapid/ultrarapid metabolizers. In summary, pk gene variation can predict serum concentrations, and thus the combination of pharmacogenetic testing and therapeutic drug monitoring is a useful tool in a personalized therapy approach for depression.
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Amitriptilina , Citocromo P-450 CYP2D6 , Antidepressivos/uso terapêutico , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2D6/genética , Feminino , Genótipo , Humanos , Masculino , Cloridrato de Venlafaxina/uso terapêuticoRESUMO
The neuropathological mechanisms leading to suicidality are still unknown, which, in view of an annual toll of around 1 million completed suicides constitutes an urgent clinical and societal problem. Alterations of stress hormone (ACTH and cortisol, representing the activity of the hypothalamic-pituitary-adrenocortical, HPA axis) regulation has been repeatedly studied in context of suicidality. Following a suicide attempt, stress hormone activity seems to be blunted, while depressed patients with suicidal ideation often present with elevated HPA axis activity. METHODS: We investigated the effects of different forms of suicidality on HPA axis regulation in 568 hospitalized patients of the Munich Antidepressant Response Signature (MARS) project. All patients had a diagnosis of a depressive disorder; 62 patients reported a recent suicide attempt, 192 patients suicide ideation, and 171 patients expressed weariness of life as the weakest form of suicidality, the latter not being analyzed in studies so far. All patients participated in the combined dexamethasone/corticotropin releasing hormone (dex/CRH) test for assessing HPA axis regulation shortly after admission to the hospital. RESULTS: We found an increased ACTH and cortisol response following the dex/CRH-test in patients that were weary of life. In contrast, stress hormone response in suicide attempters and suicide ideators did not differ from non-suicidal patients. Further, repeated suicide attempts in patients' history were associated with more pronounced stress hormone attenuation. CONCLUSION: In this so far largest study analyzing the HPA axis with respect to suicidality, we could not confirm the assumption of a general attenuation of HPA axis response in depressed suicide ideators and attempters. Conversely, HPA axis appears to be influenced by divergent effects of a specific suicidal psychopathology as well as outlasting effects of previous suicide attempts. We discuss these findings in the light of recent concepts of suicidality, pointing to multifactorial effects of acute and predisposing conditions on HPA axis reactivity in depressed patients.
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Depressão , Fadiga , Ideação Suicida , Tentativa de Suicídio , Hormônio Adrenocorticotrópico/metabolismo , Depressão/metabolismo , Depressão/fisiopatologia , Humanos , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologiaRESUMO
OBJETIVO: La Monitorización Terapéutica de Drogas (llamada en inglés TDM: therapeutic drug monitoring) combina la cuantificación de las concentraciones de medicamentos en la sangre, la interpretación farmacológica y las directrices de tratamiento. La TDM introduce una herramienta de medicina de precisión en una ípoca de gran conciencia de la necesidad de tratamientos personalizados en neurología y psiquiatría. Las indicaciones claras de la TDM incluyen la ausencia de respuesta clínica en el rango de dosis terapéuticas, la evaluación de la adherencia farmacológica, problemas de tolerancia e interacciones medicamentosas. MÉTODOS: Basándose en la literatura existente, se describieron los rangos de referencia terapéutica recomendables, los valores críticos de laboratorio y los niveles de recomendación para usar la TDM para la optimización de dosis sin indicaciones específicas, se calcularon los factores de conversión, los factores para el cálculo de concentraciones medicamentosas relacionadas con la dosis (en inglés DRC dose-to-ratioconcentration) y el cociente entre el metabolito y el compuesto original (en inglés se llama MPR: metabolite-to-parent ratio). RESULTADOS: Este resumen de las guías actualizadas del consenso por la Task Force del TDM del Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie, ofrece el conocimiento práctico y teórico para la integración de la TDM como parte de la farmacoterapia con medicamentos neuropsiquiátricos en la práctica clínica rutinaria. CONCLUSIONES: La presente traducción en español, de la guía para la aplicación del TDM en medicamentos neuropsiquiátricos, tiene como objetivo ayudar a los clínicos a mejorar la seguridad y la eficacia de los tratamientos
OBJECTIVES: Therapeutic drug monitoring (TDM) combines the quantification of drug concentrations in blood, pharmacological interpretation, and treatment guidance. TDM introduces a precision medicine tool in times of increasing awareness of the need for personalised treatment. In neurology and psychiatry, TDM can guide pharmacotherapy for patient subgroups such as children, adolescents, pregnant women, elderly patients, patients with intellectual disabilities, patients with substance use disorders, individuals with pharmacokinetic peculiarities, and forensic patients. Clear indications for TDM include lack of clinical response in the therapeutic dose range, assessment of drug adherence, tolerability issues, and drug-drug interactions. METHODS: Based upon existing literature, recommended therapeutic reference ranges, laboratory alert levels, and levels of recommendation to use TDM for dosage optimisation without specific indications, conversion factors, factors for calculation of dose-related drug concentrations, and metabolite-to-parent ratios were calculated. RESULTS: This summary of the updated consensus guidelines by the TDM task force of the Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie (AGNP) offers the practical and theoretical knowledge for the integration of TDM as part of pharmacotherapy with neuro- psychiatric agents into clinical routine. CONCLUSIONS: The present guidelines for TDM application for neuropsychiatric agents aim to assist clinicians in enhancing safety and efficacy of treatment
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Humanos , Neurofarmacologia/métodos , Neurofarmacologia/normas , Monitoramento de Medicamentos/métodos , Monitoramento de Medicamentos/normas , Fármacos do Sistema Nervoso Central/administração & dosagem , Fármacos do Sistema Nervoso Central/farmacocinéticaRESUMO
Polymorphisms in the drug transporter gene ABCB1 predict the treatment response of selected antidepressants and limit anticonvulsive medication's effectiveness. The ABCB1 locus encodes the energy-dependent transporter P-glycoprotein (P-gp) of the blood brain barrier (BBB), which serves as an efflux pump of its substrates in the expressing tissues of vertebrates. One experimental setup to determine a posteriori the P-gp substrate status is the use of the double abcb1ab knock-out (KO) mice model. Since so far, P-gp substrate status of donepezil, a cholinesterase inhibitor wildly used in Alzheimer's disease therapy was inconclusive, we performed subcutanous (s.c.), continuous injections over 11 days in double abcb1ab KO and P-gp competent wildtype (WT) mice. Both in brain and in testis concentrations of donepezil were significantly higher in P-gp deficient mice compared to WT controls (2.39 and 2.24 times respectively). In conclusion, in mice donepezil's brain bioavailability depends on P-gp.
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Doença de Alzheimer , Inibidores da Colinesterase , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Inibidores da Colinesterase/farmacologia , Donepezila , Masculino , Camundongos , Camundongos KnockoutRESUMO
BACKGROUND: Depressed patients have an increased risk of myocardial infarction, for which acute stress is a frequent trigger. Prothrombotic changes could be one involved mechanism that can be modulated by psychological coping. PURPOSE: We examined the effects of remitted major depression and situation-specific coping strategies on stress-induced coagulation activation. METHODS: Forty patients with remitted depression and 23 healthy controls underwent the Trier Social Stress Test, rating applied coping strategies thereafter. Blood was sampled at baseline and 15 and 45 min poststress to measure fibrinogen, von Willebrand factor (VWF) and D-dimer. Coagulation activation over time was quantified as area under the curve (AUC) with respect to baseline activity. Standardized z-scores of individual coagulation AUC measures were added up to a prothrombotic index. RESULTS: Stress provoked significant VWF (p = .024) and D-dimer (p = .002) responses. Remitted depressed patients used positive distraction coping more frequently than controls did (p = .030). Coagulation AUC measures were similar in both groups. In all participants, higher positive coping total (p = 0.009), driven by devaluation/defense (p = .022) and distraction (p = .004) coping, was associated with a lower prothrombotic index. In controls, but not in remitted depressed patients, higher positive coping total (p = .008), driven by higher devaluation/defense (p = .010) and distraction (p = .023) coping, was associated with lower VWF AUC. CONCLUSIONS: Despite the use of favorable coping strategies in a specific stress situation, remitted depressed patients may benefit less from a positive effect of positive situational coping on coagulation activation than controls. Such a mechanism could partially explain the increased risk of myocardial infarction in depressed individuals.
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Adaptação Psicológica/fisiologia , Coagulação Sanguínea/fisiologia , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/fisiopatologia , Estresse Psicológico/sangue , Estresse Psicológico/fisiopatologia , Adolescente , Adulto , Biomarcadores/sangue , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinogênio/análise , Humanos , Masculino , Indução de Remissão , Adulto Jovem , Fator de von Willebrand/análiseRESUMO
OBJECTIVES: Hypercoagulability is one mechanism to explain the increased risk of incident atherothrombotic disease in patients with major depressive disorder (MDD). We examined whether patients with remitted MDD show an enhanced procoagulant state. METHODS: 63 individuals (median age 35 years, 59% women), 40 with a DSM-IV diagnosis of remitted MDD, made by a clinical interview, and 23 healthy controls provided blood samples for the measurement of fibrinogen, D-dimer, von Willebrand factor, and plasminogen activator inhibitor-1. Standardised z-scores of plasma levels of these haemostatic factors were added to form a procoagulant index (PCI) as the primary outcome variable. Self-ratings of residual depressive symptoms and trait anxiety were also obtained. RESULTS: Compared with controls, remitted MDD patients had higher PCI (p = 0.013, Cohen's d = 0.69) and fibrinogen (p = 0.001, d = 0.91), controlling for age, sex, body mass index, smoking and C-reactive protein. There were no significant associations of the PCI and individual haemostatic molecules with age of MDD onset, time since the last MDD episode, the number of previous MDD episodes and residual depressive symptoms. Additional adjustment for anxiety symptoms did not change these results. CONCLUSIONS: Remitted MDD is associated with an enhanced procoagulant state. Hypercoagulability seems more a trait than a state characteristic of depression.
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Transtorno Depressivo Maior , Adulto , Ansiedade , Índice de Massa Corporal , Depressão , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , MasculinoRESUMO
Past studies examining the effect of chronotype and social jetlag on psychological well-being have been inconsistent so far. Here, we recruited participants from the general population and enquired about their natural sleeping behavior, sleep quality, depressive symptoms, and perceived stress. Partial correlations were computed between sleep variables and indicators of psychological well-being, controlling for age and sex. Less sleep during work days was found a good indicator for impairments in psychological well-being. In exploratory follow-up analyses, the same correlations were calculated within groups of early, intermediate, and late chronotype. We observed that the composition of the sample in terms of chronotype influenced whether associations between sleep variables and psychological well-being could be observed, a finding that is advised to be taken into account in future studies.
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Ritmo Circadiano/fisiologia , Síndrome do Jet Lag/epidemiologia , Síndrome do Jet Lag/psicologia , Saúde Mental/estatística & dados numéricos , Adulto , Depressão/epidemiologia , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Sono , Estresse Psicológico/epidemiologiaRESUMO
Major depression is a stress-related disorder with robust clinical and preclinical data implicating that both, dysregulation of the hypothalamus-pituitary-adrenocortical (HPA) axis and of the neurotrophin system of the brain are involved in the pathophysiology. Genetic variations within the brain-derived neurotrophic factor (BDNF) gene region, a major representative of the brain neurotrophins, are suggested to influence response to antidepressant treatment. Specifically, we recently identified two BDNF single nucleotide polymorphisms (SNP), rs2049046 and rs11030094, as associated with antidepressant treatment response in a large pharmacogenetic study of hospitalized patients. We now analyzed these two SNPs in a sub-sample for their association with HPA axis dysregulation using the combined dexamethasone suppression/corticotropin releasing hormone challenge (dex/CRH) test at hospital admission (Nâ¯=â¯266) and at discharge (Nâ¯=â¯190). Rs11030094, located 3' outside the coding region of BDNF, is also located in an intron of BDNFOS coding for a functional antagonist of BDNF. We further included the non-synonymous Val66Met (rs6265) polymorphism in our analysis, for which - albeit being extensively studied - conflicting results in respect to its role in antidepressant treatment response have been reported. Similar to the previous analysis, rs2049046 and rs11030094 showed a significant effect on antidepressant response. In a gene-dose dependent manner, we found significant lower cortisol responses to the dex/CRH test at discharge in carriers of the respective SNP alleles ('T' of rs2049046 and 'G' of rs11030094) that were associated with antidepressant response (beneficial alleles). These genetic effects on HPA axis regulation were independent of age, sex, medication and depressive symptomatology. Although not reaching statistical significance, the same direction of effect was observed for cortisol at admission, as well as the ACTH response at admission and discharge. An interaction analysis of both SNPs revealed highest cortisol levels in subjects that were non-carriers of both beneficial alleles. The Val66Met (rs6265) was neither associated with antidepressant response nor with HPA axis regulation. Our findings provide further evidence for an interaction of the HPA axis and the neurotrophin system in major depression. This study stresses the importance investigating BDNF variants beyond the extensively studied Val66Met polymorphism. In-depth analyses of both pathophysiologically relevant systems may point to possible new targets for pharmaceutical intervention and precision medicine of major depression in the future.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Transtorno Depressivo Maior/genética , Sistema Hipotálamo-Hipofisário/fisiopatologia , Íntrons , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/fisiopatologia , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Adverse experiences and chronic stress are well-known risk factors for the development of major depression, and an impaired stress response regulation is frequently observed in acute depression. Impaired glucocorticoid receptor (GR) signalling plays an important role in these alterations, and a restoration of GR signalling appears to be a prerequisite of successful antidepressant treatment. Variants in genes of the stress response regulation contribute to the vulnerability to depression in traumatized subjects. Consistent findings point to an important role of FKBP5, the gene expressing FK506-binding protein 51 (FKBP51), which is a strong inhibitor of the GR, and thus, an important regulator of the stress response. We investigated the role of FKBP5 and FKB51 expression with respect to stress response regulation and antidepressant treatment outcome in depressed patients. This study included 297 inpatients, who participated in the Munich Antidepressant Response Signature (MARS) project and were treated for acute depression. In this open-label study, patients received antidepressant treatment according to the attending doctor's choice. In addition to the FKBP5 genotype, changes in blood FKBP51 expression during antidepressant treatment were analyzed using RT-PCR and ZeptoMARKTM reverse phase protein microarray (RPPM). Stress response regulation was evaluated in a subgroup of patients using the combined dexamethasone (dex)/corticotropin releasing hormone (CRH) test. As expected, increased FKBP51 expression was associated with an impaired stress response regulation at baseline and after six weeks was accompanied by an elevated cortisol response to the combined dex/CRH test. Further, we demonstrated an active involvement of FKBP51 in antidepressant treatment outcome. While patients responding to antidepressant treatment had a pronounced reduction of FKBP5 gene and FKBP51 protein expression, increasing expression levels were observed in nonresponders. This effect was moderated by the genotype of the FKBP5 single nucleotide polymorphism (SNP) rs1360780, with carriers of the minor allele showing the most pronounced association. Our findings demonstrate that FKBP5 and, specifically, its expression product FKBP51 are important modulators of antidepressant treatment outcome, pointing to a new, promising target for future antidepressant drug development.
Assuntos
Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Depressão/genética , Expressão Gênica , Proteínas de Ligação a Tacrolimo/genética , Adulto , Alelos , Biomarcadores , Depressão/diagnóstico , Feminino , Genótipo , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Prognóstico , Proteínas de Ligação a Tacrolimo/metabolismo , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Weight gain and metabolic changes during treatment with antidepressant drugs have emerged as an important concern, particularly in long-term treatment. It is still a matter of ongoing debate whether weight gain and metabolic perturbations with antidepressant use are the consequence of increased appetite and weight gain, respectively, or represents direct pharmacological effects of the drug on metabolism. METHODS: We therefore conducted a proof-of-concept, open-label clinical trial, hypothesizing that in exceptionally healthy men no change of metabolic parameters would occur under mirtazapine, when environmental factors such as nutrition, sleep, and physical exercise were controlled and kept constant. Over a 3-week preparation phase, 10 healthy, young men were attuned to a standardized diet adjusted to their individual caloric need, to a regular sleep/wake cycle and moderate exercise. Continuing this protocol, we administered 30 mg mirtazapine daily for 7 days. RESULTS: While no significant weight gain or changes in resting energy expenditure were observed under these conditions, hunger and appetite for sweets increased with mirtazapine, accompanied by a shift in energy substrate partitioning towards carbohydrate substrate preference as assessed by indirect calorimetry. Furthermore, with mirtazapine, insulin and C-peptide release increased in response to a standardized meal. CONCLUSION: Our findings provide important insights into weight-independent metabolic changes associated with mirtazapine and allow a better understanding of the long-term metabolic effects observed in patients treated with antidepressant drugs. CLINICALTRIALS: gov NCT00878540. FUNDING: Nothing to declare.
RESUMO
A clinically important and well-studied transporter of the blood-brain barrier (BBB) is P-glycoprotein (P-gp), the gene product of ABCB1. Animal studies have shown that brain concentrations of many antidepressants depend on P-gp. However, biochemical properties, which might allow the prediction of pharmacodynamical involvement of P-gp have not yet been identified, hence thorough experimental testing of each novel drug is needed to determine its P-gp substrate status. In the current study, we tested the P-gp substrate status for the antidepressant vortioxetine using double abcb1ab knock-out (KO) mice. Cerebral concentrations of vortioxetine were 2.3 times higher in P-gp deficient mice compared to wildtype (WT) controls. No significant difference was found regarding the concentration of the drug in the plasma and other organs (liver, kidney, spleen) between KO and WT mice. The results of our study provide conclusive in-vivo evidence that in mice vortioxetine's brain bioavailability is P-gp dependent, expanding previous findings on this topic.