Childhood Stress, Serotonin Transporter Gene and Brain Structures in Major Depression

The underlying neurobiology of major depression (MD) is likely to represent an interaction between genetic susceptibility and environmental factors such as stress. We investigated, in a multimodal high-resolution magnetic resonance imaging (MRI) genetic study, whether reduced hippocampal volumes and other brain alterations are associated with the tri-allelic polymorphism of the serotonin transporter and childhood stress in patients with MD and healthy subjects. Patients with MD and healthy participants were investigated using high-resolution MRI and genotyping for serotonin transporter polymorphism in the promoter region of the serotonin transporter gene (SLC6A4, 5-HTTLPR). Region of interest analysis of the hippocampus, whole-brain voxel-based morphometry (VBM), and assessment of childhood stress were carried out. Patients carrying the risk S-allele developed smaller hippocampal volumes when they had a history of emotional neglect compared with patients who only had one risk factor (environmental or genetic). In patients, childhood stress also predicted further hippocampal white matter alterations independently from the genotype. Moreover, the left prefrontal cortex was smaller in patients, whereby childhood stress resulted in larger prefrontal volumes in those subjects carrying the non-risk L-allele, suggesting preventive effects. The findings indicate that subjects with both environmental and genetic risk factors are susceptible to stress-related hippocampal changes. Structural brain changes due to stress represent part of the mechanism by which the illness risk and outcome might be genetically mediated.     

Evidence for a Role of Transporter-Mediated Currents in the Depletion of Brain Serotonin Induced by Serotonin Transporter Substrates

Serotonin (5-HT) transporter (SERT) substrates like fenfluramine and 3,4-methylenedioxymethamphetamine cause long-term depletion of brain 5-HT, while certain other substrates do not. The 5-HT deficits produced by SERT substrates are dependent upon transporter proteins, but the exact mechanisms responsible are unclear. Here, we compared the pharmacology of several SERT substrates: fenfluramine, d-fenfluramine, 1-(m-chlorophenyl)piperazine (mCPP) and 1-(m-trifluoromethylphenyl)piperainze (TFMPP), to establish relationships between acute drug mechanisms and the propensity for long-term 5-HT depletions. In vivo microdialysis was carried out in rat nucleus accumbens to examine acute 5-HT release and long-term depletion in the same subjects. In vitro assays were performed to measure efflux of [³H]5-HT in rat brain synaptosomes and transporter-mediated ionic currents in SERT-expressing Xenopus oocytes. When administered repeatedly to rats (6 mg/kg, i.p., four doses), all drugs produce large sustained elevations in extracellular 5-HT (>5-fold) with minimal effects on dopamine. Importantly, 2 weeks after dosing, only rats exposed to fenfluramine and d-fenfluramine display depletion of brain 5-HT. All test drugs evoke fluoxetine-sensitive efflux of [³H]5-HT from synaptosomes, but d-fenfluramine and its bioactive metabolite d-norfenfluramine induce significantly greater SERT-mediated currents than phenylpiperazines. Our data confirm that drug-induced 5-HT release probably does not mediate 5-HT depletion. However, the magnitude of transporter-mediated inward current may be a critical factor in the cascade of events leading to 5-HT deficits. This hypothesis warrants further study, especially given the growing popularity of designer drugs that target SERT.     

Pharmacological Blockade of 5-HT7 Receptors as a Putative Fast Acting Antidepressant Strategy

Current antidepressants still display unsatisfactory efficacy and a delayed onset of therapeutic action. Here we show that the pharmacological blockade of serotonin 7 (5-HT₇) receptors produced a faster antidepressant-like response than the commonly prescribed antidepressant fluoxetine. In the rat, the selective 5-HT₇ receptor antagonist SB-269970 counteracted the anxiogenic-like effect of fluoxetine in the open field and exerted an antidepressant-like effect in the forced swim test. In vivo, 5-HT₇ receptors negatively regulate the firing activity of dorsal raphe 5-HT neurons and become desensitized after long-term administration of fluoxetine. In contrast with fluoxetine, a 1-week treatment with SB-269970 did not alter 5-HT firing activity but desensitized cell body 5-HT autoreceptors, enhanced the hippocampal cell proliferation, and counteracted the depressive-like behavior in olfactory bulbectomized rats. Finally, unlike fluoxetine, early-life administration of SB-269970, did not induce anxious/depressive-like behaviors in adulthood. Together, these findings indicate that the 5-HT₇ receptor antagonists may represent a new class of antidepressants with faster therapeutic action.     

Effect of Tryptophan Depletion on Mood in Male and Female Volunteers: A Pilot Study

We studied 12 healthy subjects, six males and six females, using the technique of tryptophan depletion in a double-blind placebo controlled crossover design. Subjects rated their subjective mood and also underwent a mood induction procedure. The tryptophan free mixture significantly lowered plasma total and free tryptophan at +5 h. After the tryptophan-free mixture, subjective ratings of mood fell in the females but not in the males. Whilst the mood induction procedure was effective at lowering mood, it did not have any greater effect on the day of tryptophan depletion in either women or men. © 1997 by John Wiley & Sons, Ltd.     

Serotonin autoreceptor in rat hippocampus: Pharmacological characterization as a subtype of the 5-HT1 receptor

Summary The 5-hydroxytryptamine (5-HT) autoreceptors mediating inhibition of [³H]5-HT release in rat hippocampus have been characterized pharmacologically in terms of 5-HT receptor subtype by using superfused synaptosomes depolarized with 15 mM KCl. Exogenous 5-HT inhibited in a concentration-dependent way (pEC₃₀=8.74) the K⁺-evoked release of [³H]5-HT. Methiothepin shifted the concentration-response curve of 5-HT to the right (pA₂=8.62). The 5-HT₂ receptor antagonists, ketanserin, methysergide or spiperone were ineffective against 5-HT. The 5-HT₁ receptor agonist, 5-methoxy-3-[1,2,3,6-tetra-hydropyridin-4-yl]-1H-indole (RU 24969) mimicked 5-HT and was equipotent as an inhibitor of the release of [³H]5-HT. In contrast, the putative 5-HT_1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) was almost ineffective at 1 M. Finally, (–)propranolol, used as a non-selective 5-HT_1A/5-HT_1B receptor antagonist, shifted to the right (pA₂=7.91) the concentration-response curve of 5-HT whereas the 5-HT_1C receptor antagonist mesulergine was ineffective. In conclusion, 5-HT nerve terminals of rat hippocampus possess autoreceptors which appear to belong to the 5-HT_1B subtype.     

甲状腺乳头状癌组织中RASSF1A基因启动子甲基化与临床病理学的关系

目的：探讨甲状腺乳头状癌及癌旁组织中RASSF1A基因启动子甲基化改变的特点与临床特征的关系。方法：从甲状腺乳头状癌及癌旁组织中提取基因组DNA,采用甲基化特异性PCR检测RASSF1A基因启动子甲基化情况。结果：（1）甲状腺乳头状癌组织中RASSF1A基因启动子甲基化的发生率为55．9％（19／34）,癌旁组织中RASSF1A基因启动子的甲基化的发生率为23．5％（8／34）,癌组织中RASSF1A基因启动子甲基化显著高于癌旁组织（P〈0．05）。（2）有淋巴结转移的甲状腺乳头状癌组织RASSF1A基因启动子的甲基化的发生率为77．8％（14／18）,高于无淋巴结转移组的31．3％（5,16）,差异有统计学意义（P〈0．05）。（3）临床Ⅱ～Ⅲ期甲状腺乳头状癌患者中RASSF1A基因启动子的甲基化发生率为88．9％（8／9）,高于I期的44．0％（11／25）,差异有统计学意义（P〈0．05）。结论：甲状腺乳头状癌组织中存在RASSF1A基因启动子区的异常甲基化,甲基化可能与甲状腺乳头状癌发生发展过程有关。     

Serotonin 1A Receptor Binding of [11C]CUMI-101 in Bipolar Depression Quantified Using Positron Emission Tomography: Relationship to Psychopathology and Antidepressant Response

BackgroundThe pathophysiology of bipolar disorder (BD) remains largely unknown despite it causing significant disability and suicide risk. Serotonin signaling may play a role in the pathophysiology, but direct evidence for this is lacking. Treatment of the depressed phase of the disorder is limited. Previous studies have indicated that positron emission tomography (PET) imaging of the serotonin 1A receptor (5HT1AR) may predict antidepressant response.MethodsA total of 20 participants with BD in a current major depressive episode and 16 healthy volunteers had PET imaging with [¹¹C]CUMI-101, employing a metabolite-corrected input function for quantification of binding potential to the 5HT1AR. Bipolar participants then received an open-labeled, 6-week clinical trial with a selective serotonin reuptake inhibitor (SSRI) in addition to their mood stabilizer. Clinical ratings were obtained at baseline and during SSRI treatment.ResultsPretreatment binding potential (BP_F) of [¹¹C]CUMI-101 was associated with a number of pretreatment clinical variables within BD participants. Within the raphe nucleus, it was inversely associated with the baseline Montgomery Åsberg Rating Scale (P = .026), the Beck Depression Inventory score (P = .0023), and the Buss Durkee Hostility Index (P = .0058), a measure of lifetime aggression. A secondary analysis found [¹¹C]CUMI-101 BP_F was higher in bipolar participants compared with healthy volunteers (P = .00275). [¹¹C]CUMI-101 BP_F did not differ between SSRI responders and non-responders (P = .907) to treatment and did not predict antidepressant response (P = .580). Voxel-wise analyses confirmed the results obtained in regions of interest analyses.ConclusionsA disturbance of serotonin system function is associated with both the diagnosis of BD and its severity of depression. Pretreatment 5HT1AR binding did not predict SSRI antidepressant outcome.The study was listed on clinicaltrials.gov with identifier {"type":"clinical-trial","attrs":{"text":"NCT02473250","term_id":"NCT02473250"}}NCT02473250.     

Quantification of the Serotonin 1A Receptor Using PET: Identification of a Potential Biomarker of Major Depression in Males

Multiple lines of research have implicated the serotonin 1A (5-HT_1A) receptor in major depressive disorder (MDD). Despite this, quantification of 5-HT_1A is yet to yield a clinically relevant MDD biomarker. One reason may be that reported sex differences in the serotonergic system confound the comparison between diagnostic groups. Therefore, this study sought to determine whether differences in 5-HT_1A binding between depressed and control subjects are affected by sex. Using positron emission tomography (PET), serotonin 1A binding was quantified in 50 patients with MDD (34 female, 16 male) and 57 healthy controls (32 female, 25 male). The subjects'' 5-HT_1A density (BP_F, equal to the product of the density of available receptors and tracer affinity), was determined by using the PET tracer [carbonyl-C-11]-WAY-100635, a selective 5-HT_1A antagonist. Results indicated that male MDD subjects had a 67.0% higher BP_F across 13 brain regions compared with male controls (df=103, p<0.0001). The greatest difference between MDD subjects and controls was in the raphe (132%, p=0.000). Furthermore, by using a threshold, male controls can be distinguished from depressed males with high sensitivity and specificity (both >80%). In females, the separation between diagnostic groups yields much lower sensitivity and specificity. This data therefore suggests a specific biosignature for MDD in males. Identification of such a biosignature could provide a deeper understanding of depression pathology, help identify those at highest risk, and aid in the development of new therapies. Further, these findings suggest that combining male and female cohorts may not be optimal for some MDD studies.     

Selective DNA Methylation of BDNF Promoter in Bipolar Disorder: Differences Among Patients with BDI and BDII

The etiology of bipolar disorder (BD) is still poorly understood, involving genetic and epigenetic mechanisms as well as environmental contributions. This study aimed to investigate the degree of DNA methylation at the promoter region of the brain-derived neurotrophic factor (BDNF) gene, as one of the candidate genes associated with major psychoses, in peripheral blood mononuclear cells isolated from 94 patients with BD (BD I=49, BD II=45) and 52 healthy controls. A significant BDNF gene expression downregulation was observed in BD II 0.53±0.11% P<0.05), but not in BD I (1.13±0.19%) patients compared with controls (CONT: 1±0.2%). Consistently, an hypermethylation of the BDNF promoter region was specifically found in BD II patients (CONT: 24.0±2.1% BDI: 20.4±1.7% BDII: 33.3±3.5%, P<0.05). Of note, higher levels of DNA methylation were observed in BD subjects on pharmacological treatment with mood stabilizers plus antidepressants (34.6±4.2%, predominantly BD II) compared with those exclusively on mood-stabilizing agents (21.7±1.8% P<0.01, predominantly BD I). Moreover, among the different pharmacological therapies, lithium (20.1±3.8%, P<0.05) and valproate (23.6±2.9%, P<0.05) were associated with a significant reduction of DNA methylation compared with other drugs (35.6±4.6%). Present findings suggest selective changes in DNA methylation of BDNF promoter in subjects with BD type II and highlight the importance of epigenetic factors in mediating the onset and/or susceptibility to BD, providing new insight into the mechanisms of gene expression. Moreover, they shed light on possible mechanisms of action of mood-stabilizing compounds vs antidepressants in the treatment of BD, pointing out that BDNF regulation might be a key target for their effects.     

Subanesthetic Doses of Ketamine Transiently Decrease Serotonin Transporter Activity: A PET Study in Conscious Monkeys

Subanesthetic doses of ketamine, an N-methyl-D-aspartic acid (NMDA) antagonist, have a rapid antidepressant effect which lasts for up to 2 weeks. However, the neurobiological mechanism regarding this effect remains unclear. In the present study, the effects of subanesthetic doses of ketamine on serotonergic systems in conscious monkey brain were investigated. Five young monkeys underwent four positron emission tomography measurements with [¹¹C]-3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl)benzonitrile ([¹¹C]DASB) for the serotonin transporter (SERT), during and after intravenous infusion of vehicle or ketamine hydrochloride in a dose of 0.5 or 1.5 mg/kg for 40 min, and 24 h post infusion. Global reduction of [¹¹C]DASB binding to SERT was observed during ketamine infusion in a dose-dependent manner, but not 24 h later. The effect of ketamine on the serotonin 1A receptor (5-HT_1A-R) and dopamine transporter (DAT) was also investigated in the same subjects studied with [¹¹C]DASB. No significant changes were observed in either 5-HT_1A-R or DAT binding after ketamine infusion. Microdialysis analysis indicated that ketamine infusion transiently increased serotonin levels in the extracellular fluid of the prefrontal cortex. The present study demonstrates that subanesthetic ketamine selectively enhanced serotonergic transmission by inhibition of SERT activity. This action coexists with the rapid antidepressant effect of subanesthetic doses of ketamine. Further studies are needed to investigate whether the transient combination of SERT and NMDA reception inhibition enhances each other''s antidepressant actions.     

Effect of acute and repeated versus sustained administration of the 5-HT1A receptor agonist ipsapirone: electrophysiological studies in the rat hippocampus and dorsal raphe

The present study was aimed at examining the adaptation of presynaptic 5-HT_1A autoreceptors in the dorsal raphe and of postsynaptic 5-HT_1A receptors in the dorsal hippocampus during long-term administration of the 5-HT_1A receptor agonist ipsapirone given either repeatedly or in a sustained fashion. Concurrent microiontophoretic application of ipsapirone did not attentuate the suppressant effect of 5-hydroxytyptamine (5-HT) on 5-HT neurons, but markedly decreased it when co-applied on CA₃ pyramidal neurons in the dorsal hippocampus. Thus, ipsapirone acted as a full agonist in the dorsal raphe and as a partial agonist in the dorsal hippocampus. Ipsapirone (15 mg/kg/day, s.c. × 2 days) delivered by osmotic minipumps markedly decreased the firing activity of the dorsal raphe 5-HT neurons. After 14 days of treatment, there was a complete recovery of their firing activity and a desensitization of their somatodendritic 5-HT_1A autoreceptors, as assessed using microiontophoretic applications of 5-HT and 8-hydroxy-2(di-n-propylamino)tetraline (8-OH-DPAT) onto 5-HT neurons. The same degree of desensitization was obtained when ipsapirone was administered with repeated injections (7.5 mg/kg b.i.d., s.c. × 14 days). In contrast, the two modalities of ipsapirone adminsitration left unaltered the responsiveness of CA₃ pyramidal neurons to microiontophoretic applications of 5-HT and 8-OH-DPAT. In conclusion, long-term administration of ipsapirone most likely increases 5-HT neurotransmission by enhancing the tonic activation of postsynaptic 5-HT_1A receptors. Therefore, the use of sustained release preparation of 5-HT_1A receptor agonists should not alter their therapeutic effectiveness in anxiety and affective disorders since the same effects on 5-HT_1A receptor functions were produced in this rat model by the sustained and the repeated modes of administration of ipsapirone. Received: 24 September 1996 / Accepted: 28 April 1997     

我国5-羟色胺3受体拮抗药预防化疗后呕吐的药物经济学系统评价

目的:评价我国5-羟色胺3(5-HT3)受体拮抗药用于化疗后呕吐的成本-效果,为临床治疗方案选择、药物遴选、药物政策制定提供参考。方法:运用循证医学系统评价及药物经济学研究方法,通过检索国内发表文献,按照纳入及排除标准收集相关药物经济学文献,制定方法学质量评价标准和外在适用性评价标准,对相关数据进行综合分析。结果与结论:最终纳入16篇文献,大部分方法学质量较低。不推荐甲氧氯普胺用于顺铂、环磷酰胺等高致吐风险化疗药的呕吐预防;格拉司琼的成本-效果比优于昂丹司琼,同时二者优于阿扎司琼;托烷司琼在各5-HT3受体拮抗药中成本-效果较差。由于各研究样本量较少,结论尚需高质量、大样本试验支持。     

Disproportionate Reduction of Serotonin Transporter May Predict the Response and Adherence to Antidepressants in Patients with Major Depressive Disorder: A Positron Emission Tomography Study with 4-[18F]-ADAM

Background:

Many lines of evidence suggest the role of serotonin transporter (SERT)-mediated reuptake of serotonin in the pathophysiology and treatment of major depressive disorder (MDD). This study aimed to examine whether the pretreatment of SERT binding potential or SERT binding ratio between terminal projection regions relative to the midbrain raphe nuclei was associated with treatment outcomes to SERT-targeted antidepressants.

Methods:

We recruited 39 antidepressant-naïve patients with MDD and 39 heathy controls. Positron emission tomography with N,N-dimethyl-2-(2-amino-4-[¹⁸F]fluorophenylthio)benzylamine (4-[¹⁸F]-ADAM) was used to measure in vivo SERT availability prior to antidepressant treatment. The 21-item Hamilton Depression Rating Scale (HDRS) was use to assess the severity of depression from baseline to week 6. All the patients with MDD had HDRS scores of 18 or more.

Results:

Pretreatment SERT binding in the thalamus and striatum positively correlated with an early reduction in HDRS scores at week 3. Nonresponders and dropout patients showed a proportionate reduction in SERT binding in the terminal projection regions and midbrain compared to healthy controls. In contrast, a disproportionate reduction in SERT binding in the terminal projection regions relative to midbrain was observed in responders.

Conclusions:

The results of this study suggested that a disproportionate reduction in SERT binding between terminal projection regions and midbrain may predict better treatment outcomes in patients with MDD.     

Injection of Resperpine into Zebrafish, Prevents Fish to Fish Communication of Radiation-Induced Bystander Signals: Confirmation in Vivo of a Role for Serotonin in the Mechanism

Serotonin (5-HT) has been implicated as a potential modulator of the bystander effect in cell cultures. To assess the relevance of serotonin in vivo experiments were done with the zebrafish (Danio rerio). This species, when irradiated, transmits bystander signals to non-irradiated fish. The animals were injected with reserpine, an inhibitor of serotonin at a dose of 80mg/kg of body mass. The results show that reserpine treated fish had only 27% of the serotonin in non-treated fish. Skin tissue samples were collected from the fish and assayed for bystander signal production using a reporter bioassay. Reserpine prevented the production and communication of signals between fish. Intracellular calcium flux, identified as a bystander response in the reporter cells confirmed this. Medium harvested from tissues of X-rayed fish and their bystanders, showed an oscillating pattern of calcium flux. Samples from X-rayed fish pretreated with reserpine produced a chaotic pattern of random fluctuations in the reporter cells, while their bystander fish led to increased calcium, but no oscillations. These results suggest that 5-HT is involved in bystander signalling in zebrafish, and by decreasing the amount of available 5-HT the bystander effect can be blocked.     

Characterization of a novel effect of serotonin 5-HT1A and 5-HT2A receptors: increasing cGMP levels in rat frontal cortex

Elucidating the mechanisms of action of hallucinogens has become an increasingly important area of research as their abuse has grown in recent years. Although serotonin receptors appear to play a role in the behavioral effects of the phenethylamine and indoleamine hallucinogens, the signaling pathways activated by these agents are unclear. Here it is shown that administration of serotonin (5-hydroxytryptamine, 5-HT) increased cyclic guanosine monophosphate (cGMP) production in frontal cortical slices of rat brain. The effect of 5-HT was greater than that of N-methyl-D-aspartate (NMDA), a stimulant of cGMP formation in the central nervous system. The 5-HT_2A/2C receptor phenethylamine agonist, 2,5-dimethoxy-4-methylamphetamine (DOM), increased cGMP content in the slices. Additionally 8-hydroxy-2-(di-n-propylamino)tetralin (DPAT), a 5-_HT1A/7 receptor agonist also increased cGMP production. Stimulation of cGMP formation by DOM was prevented by a 5-HT_2A/2C receptor antagonist, pirenperone, as well as by a 5-HT_2A receptor selective antagonist, MDL100907. A 5-HT_2C receptor antagonist, SB242084, did not block the effect of DOM. Stimulation of cGMP production by DPAT was blocked by the 5-HT_1A receptor antagonist, WAY100635. Stimulation of cGMP formation by serotonin could be prevented by pirenperone orWAY100635. In summary, activation of serotonin 5-HT_1A and 5-HT_2A receptors increase brain cGMP levels.     

Linalool as a Therapeutic and Medicinal Tool in Depression Treatment: A Review

Depression is a prevalent disease worldwide, limiting psychosocial functioning and thequality of life. Linalool is the main constituent of some essential oils from aromatic plants, representing about 70% of these volatile concentrates. Evidence of the linalool activity on the central nervous system, mainly acting as an antidepressant agent, is increasingly abundant. This review aimed to extend the knowledge of linalool''s antidepressant action mechanisms, which is fundamental for future research, intending to highlight this natural compound as a new antidepressant phytomedication. A critical analysis is proposed here with probable hypotheses of the synergic mechanisms that support the evidence of antidepressant effects of the linalool. The literature search has been conducted in databases for published scientific articles before December 2020, using relevant keywords. Several pieces of evidence point to the anticonvulsant, sedative, and anxiolytic actions. In addition to these activities, other studies have revealed that linalool acts on the monoaminergic and neuroendocrine systems, inflammatory process, oxidative stress, and neurotrophic factors, such as BDNF, resulting in considerable advances in the knowledge of the etiology of depression. In this context, linalool emerges as a promising bioactive compound in the therapeutic arsenal, capable of interacting with numerous pathophysiological factors and acting on several targets. This review claims to contribute to future studies, highlighting the gaps in the linalool knowledge, such as its kinetics, doses, routes of administration, and multiple targets of interaction, to clarify its antidepressant activity.     

宫颈癌细胞系中RASSF2A基因启动子区甲基化状态的研究

目的拟通过检测4株不同宫颈癌细胞系HeLa、CaSki、SiHa和C33A中RASSF2A基因启动子区甲基化水平,以及分析去甲基化前后RASSF2A基因mRNA和蛋白表达水平、甲基化状态及细胞生物活性的变化,探讨宫颈癌发生的可能机制及治疗对策。方法采用实时定量聚合酶链反应方法检测去甲基化药物5-杂氮-2′-脱氧胞苷（5-aza-dC）作用前后RASSF2A基因的表达;甲基化特异性PCR（MSP）法检测4株宫颈癌细胞系中RASSF2A启动子区甲基化状态;免疫细胞化学方法检测RASSF2A基因表达变化,并用MTT法和流式细胞术观察细胞生物活性的变化。结果宫颈癌细胞系HeLa和SiHa表现为完全甲基化状态,细胞系CaSki和C33A表现为部分甲基化状态。5-aza-dC可使宫颈癌细胞系部分去甲基化,并使RASSF2A基因在宫颈癌细胞中mRNA和蛋白水平表达均显著升高。通过对宫颈癌细胞系HeLa的生物学行为检测发现,通过5-aza-dC的诱导作用,其增殖能力和抗凋亡能力明显下降。结论甲基化是导致宫颈癌细胞中RASSF2A基因表达缺失或降低的重要原因之一。去甲基化药物5-aza-dC能够逆转宫颈癌细胞系RASSF2A基因启动子异常甲基化水平,提高RASSF2A基因的mRNA和蛋白表达水平,提示RASSF2A基因的甲基化水平可以作为评估去甲基化干预是否有效的分子学标志物,为宫颈癌的临床治疗提供新的分子靶点。     

Extended Release Quetiapine Fumarate (Quetiapine XR) as Adjunct Therapy in Patients with Generalized Anxiety Disorder and a History of Inadequate Treatment Response: A Randomized,Double-Blind Study

Objective

To evaluate the efficacy and tolerability of adjunct extended release quetiapine fumarate (quetiapine XR) in patients with generalized anxiety disorder (GAD) and inadequate response to selective serotonin reuptake inhibitors/ serotonin norepinephrine reuptake inhibitors (SSRI/SNRIs).

Methods

11-week (1-week single-blind placebo run-in; 8-week randomized treatment; 2-week post-treatment period), double-blind, placebo-controlled study. Patients were randomized to quetiapine XR or placebo adjunct to SSRI/SNRI. 50 mg initial dose; 150 mg/day, Day 3; 300 mg/day, Weeks × and 4 if indicated (Clinical Global Impressions-Severity of Illness [CGI-S] ≥ 4; 150 mg/day tolerated). Primary endpoint: change from randomization to Week 8 in HAM-A total score. Secondary variables: Hamilton Rating Scale for Anxiety (HAM-A) psychic/somatic clusters, response and remission; and CGI-S.

Results

409 patients were randomized to quetiapine XR (n = 209) or placebo (n = 200); 41% and 55% of patients, respectively, had dose increases (300 mg/day). Week 8 mean change in HAM-A total score was not statistically significant for quetiapine XR (–10.74; p = 0.079) versus placebo (–9.61). Secondary variables were generally consistent with the primary analysis, except a significant reduction in HAM-A total score at Week 1 (–6.45, quetiapine XR versus –4.47, placebo; p < 0.001); significant improvements in HAM-A psychic cluster (p < 0.05) and CGI-S total (p < 0.05) scores at Week 8. Adverse events (.10% either group) were dry mouth, somnolence, sedation, headache, and dizziness.

Conclusions

In patients with GAD and inadequate response to SSRI/SNRI, adjunct quetiapine XR did not show a statistically significant effect for the primary endpoint at Week 8, although some secondary endpoints were statistically significant versus placebo. Quetiapine XR was generally well tolerated.     

Incongruent Reduction of Serotonin Transporter Associated with Suicide Attempts in Patients with Major Depressive Disorder: A Positron Emission Tomography Study with 4-[18F]-ADAM

Background:

Much evidence supports the role of the serotonin transporter (SERT) in the pathophysiology and pharmacotherapy of major depressive disorder (MDD) and suicidal behaviors.

Methods:

In this study, we recruited 17 antidepressant-naïve patients with MDD and 17 age- and gender-matched healthy controls. SERT availability was measured in vivo with N,N-dimethyl-2-(2-amino-4-[¹⁸F]fluorophenylthio)benzylamine (4-[¹⁸F]-ADAM) positron emission tomography (PET) imaging. The 21-item Hamilton Depression Rating Scale (HDRS) and Beck Scale for Suicide Ideation were used to assess the severity of depression and the intent of suicide ideation prior to PET imaging. All subjects with MDD were in a current state of depression with HDRS scores ≧18. Subjects who attempted suicide within two weeks of the study onset were recruited in the depressed suicidal group (n = 8). Subjects with MDD who denied any prior suicide attempt were recruited into the depressed non-suicidal group (n = 9).

Results:

A significant reduction of SERT availability in the midbrain, thalamus, and striatum was noted in the MDD group relative to the control group (Bonferroni-adjusted p-value < 0.05). Moreover, this effect was more pronounced in the depressed suicidal group compared to the control group (Bonferroni-adjusted p-value < 0.01). Relative to both the depressed non-suicidal and control groups, the depressed suicidal group showed an increased prefrontal cortex (PFC)/midbrain SERT binding ratio (Bonferroni-adjusted p-value < 0.01).

Conclusions:

This study suggests an incongruent reduction of PFC SERT binding relative to the midbrain might discriminate between depressed suicide attempters and non-attempters in patients with MDD and may be involved in the pathophysiology of suicide behaviors.