918 resultados para Serotonin Transporter
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Introduction: Premature ejaculation ( PE) is a common male sexual disorder. An ideal, reliable and effective treatment is desired by many men and couples affected by this condition. Aim: Evaluate if the association of a phosphodiesterase- 5 inhibitor, tadalafil, and a selective serotonin reuptake inhibitor, fluoxetine, can prolong the intravaginal ejaculatory latency time ( IELT) in men with lifelong premature ejaculation. Methods: Sixty patients with lifelong premature ejaculation and without erectile dysfunction ( ED) with IELT less than 90 s were enrolled in the protocol and randomized into 4 groups to use a combination of medications: ( 1) tadalafil 20 mg plus fluoxetine 90 mg, ( 2) fluoxetine 90 mg plus placebo, ( 3) tadalafil 20 mg plus placebo, and ( 4) two different placebo capsules ( control). Before starting the medications, each man timed his IELT with a stopwatch, and likewise during the treatment period. Fluoxetine 90 mg or placebo was taken once a week plus tadalafil 20 mg or placebo within a 36- hour frame of intended sexual intercourse with a steady partner. Patients were prospectively followed for 12 weeks. One- way ANOVA was used for statistical comparisons of IELT results in each group. Results: Mean IELT before starting treatment was 51.3 +/- 23 s. With one- way ANOVA, a statistically significant difference in post- treatment IELT was seen with combination treatment compared to placebo ( p < 0.001). There were increases in IELT from baseline in patients using fluoxetine plus tadalafil ( 49.57 +/- 25.87 to 336.13 +/- 224.77) (p < 0.001), fluoxetine (56.55 +/- 18.55 to 233.62 +/- 105.08) ( p < 0.001) and tadalafil (49.26 +/- 19.43 to 186.53 +/- 159.05) (p = 0.001). The increases in each group were statistically significant compared to the placebo (49.86 +/- 19.43 to 67.82 +/- 46.18) ( p = 0.042). Conclusion: Fluoxetine plus tadalafil significantly increased the IELT from baseline in men with lifelong premature ejaculation when compared to placebo, tadalafil or fluoxetine. Copyright (C) 2008 S. Karger AG, Basel.
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Lima GA, Anhe GF, Giannocco G, Nunes MT, Correa-Giannella ML, Machado UF. Contractile activity per se induces transcriptional activation of SLC2A4 gene in soleus muscle: involvement of MEF2D, HIF-1a, and TR alpha transcriptional factors. Am J Physiol Endocrinol Metab 296: E132-E138, 2009. First published October 28, 2008; doi: 10.1152/ajpendo.90548.2008.-Skeletal muscle is a target tissue for approaches that can improve insulin sensitivity in insulin-resistant states. In muscles, glucose uptake is performed by the GLUT-4 protein, which is encoded by the SLC2A4 gene. SLC2A4 gene expression increases in response to conditions that improve insulin sensitivity, including chronic exercise. However, since chronic exercise improves insulin sensitivity, the increased SLC2A4 gene expression could not be clearly attributed to the muscle contractile activity per se and/or to the improved insulin sensitivity. The present study was designed to investigate the role of contractile activity per se in the regulation of SLC2A4 gene expression as well as in the participation of the transcriptional factors myocyte enhancer factor 2D (MEF2D), hypoxia inducible factor 1a (HIF-1a), and thyroid hormone receptor-alpha (TR alpha). The performed in vitro protocol excluded the interference of metabolic, hormonal, and neural effects. The results showed that, in response to 10 min of electrically induced contraction of soleus muscle, an early 40% increase in GLUT-4 mRNA (30 min) occurred, with a subsequent 65% increase (120 min) in GLUT-4 protein content. EMSA and supershift assays revealed that the stimulus rapidly increased the binding activity of MEF2D, HIF-1a, and TR alpha into the SLC2A4 gene promoter. Furthermore, chromatin immunoprecipitation assay confirmed, in native nucleosome, that contraction induced an approximate fourfold (P < 0.01) increase in MEF2D and HIF-1a-binding activity. In conclusion, muscle contraction per se enhances SLC2A4 gene expression and that involves MEF2D, HIF-1a, and TR alpha transcription factor activation. This finding reinforces the importance of physical activity to improve glycemic homeostasis independently of other additional insulin sensitizer approaches.
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The regulation of putrescine transport in difluoromethylornithine-treated B16 melanoma cells by extracellular Ca2+ has been investigated. It was found that physiological concentrations of Ca2+ were essential for optimum uptake of putrescine and spermidine. Mg2+, albeit at higher concentrations, also could potentiate polyamine transport. The maximum rate of putrescine uptake increased from 1698 +/-: 67 pmol/min/mg DNA in the absence of Ca2+ to 3100 +/- 98 pmol/min/mg DNA in the presence of 0.5 mM Ca2+. There was no change in K-m. While Ca2+ enhanced transport of both putrescine and spermidine it did not affect the uptake of deoxyglucose, thymidine or leucine. Putrescine did not alter Ca2+ fluxes suggesting that the two cations do not share a common transport system. The effects of Ca2+ on putrescine uptake appeared to be mediated extracellularly firstly because Ca2+ did not potentiate putrescine uptake in the presence of A23187 and secondly, because the effects of Ca2+ were completely inhibited by the lanthanide Tb3+, which binds to calcium-dependent proteins and does not readily cross biological membranes. Ca2+ did not affect putrescine transport in the absence of extracellular Na+. Moreover, the rate of putrescine uptake in the absence of Ca2+ was similar to that in the absence of extracellular Na+. The results from this study indicate that polyamine transport is stimulated by extracellular Ca2+ and suggest that Ca2+ is required for activity of the Na+-dependent transporter only. This transporter appears to possess a regulatory binding site for divalent cations. (C) 1997 Elsevier Science Ltd.
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Neural phase signaling has gained attention as a putative coding mechanism through which the brain binds the activity of neurons across distributed brain areas to generate thoughts, percepts, and behaviors. Neural phase signaling has been shown to play a role in various cognitive processes, and it has been suggested that altered phase signaling may play a role in mediating the cognitive deficits observed across neuropsychiatric illness. Here, we investigated neural phase signaling in two mouse models of cognitive dysfunction: mice with genetically induced hyperdopaminergia [dopamine transporter knock-out (DAT-KO) mice] and mice with genetically induced NMDA receptor hypofunction [NMDA receptor subunit-1 knockdown (NR1-KD) mice]. Cognitive function in these mice was assessed using a radial-arm maze task, and local field potentials were recorded from dorsal hippocampus and prefrontal cortex as DAT-KO mice, NR1-KD mice, and their littermate controls engaged in behavioral exploration. Our results demonstrate that both DAT-KO and NR1-KD mice display deficits in spatial cognitive performance. Moreover, we show that persistent hyperdopaminergia alters interstructural phase signaling, whereas NMDA receptor hypofunction alters interstructural and intrastructural phase signaling. These results demonstrate that dopamine and NMDA receptor dependent glutamate signaling play a critical role in coordinating neural phase signaling, and encourage further studies to investigate the role that deficits in phase signaling play in mediating cognitive dysfunction.
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Pentamidine is a second-line agent used in the treatment of leishmaniasis and its mode of action and mechanism of resistance is not well understood. It was previously demonstrated that transfection of promastigotes and amastigotes with the ABC transporter PRP1 gene confers resistance to pentamidine. To further clarify this point, we generated Leishmania amazonensis mutants resistant to pentamidine. Our results indicated that this ABC transporter is not associated with pentamidine resistance in lines generated by drug pressure through amplification or overexpression mechanisms of PRP1 gene. (C) 2008 Elsevier Inc. All rights reserved.
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Purpose: The aversive nature of regenerative milieu is the main problem related to the failure of neuronal restoration in the injured spinal cord which however might be addressed with an adequate repair intervention. We evaluated whether glial cell line-derived neurotrophic factor (GDNF) may increase the ability of sciatic nerve graft, placed in a gap promoted by complete transections of the spinal cord, to enhance motor recovery and local fiber growth. Methods: Rats received a 4 mm-long gap at low thoracic level and were repaired with a fragment of the sciatic nerve. GDNF was added (NERVE+GDNF) or not to the grafts (NERVE-GDNF). Motor behavior score (BBB) and sensorimotor tests-linked to the combined behavior score (CBS), which indicate the degree of the motor improvement and the percentage of functional deficit, respectively, and also the spontaneous motor behavior in an open field by means of an infrared motion sensor activity monitor were analyzed. At the end of the third month post surgery, the tissue composed by the graft and the adjacent regions of the spinal cord was removed and submitted to the immunohistochemistry of the neurofilament-200 (NF-200), growth associated protein-43 (GAP-43), microtubule associated protein-2 (MAP-2), 5-hidroxytryptamine (serotonin, 5-HT) and calcitonin gene related peptide (CGRP). The immunoreactive fibers were quantified at the epicenter of the graft by means of stereological procedures. Results: Higher BBB and lower CBS levels (p < 0.001) were found in NERVE+GDNF rats. GDNF added to the graft increased the levels of individual sensorimotor tests mainly at the third month. Analysis of the spontaneous motor behavior showed decreases in the time and number of small movement events by the third month without changes in time and number of large movement events in the NERVE+GDNF rats. Immunoreactive fibers were encountered inside the grafts and higher amounts of NF-200, GAP-43 and MAP-2 fibers were found in the epicenter of the graft when GDNF was added. A small amount of descending 5-HT fibers was seen reentering in the adjacent caudal levels of the spinal cords which were grafted in the presence of GDNF, event that has not occurred without the neurotrophic factor. GDNF in the graft also led to a large amount of MAP-2 perikarya and fibers in the caudal levels of the cord gray matter, as determined by the microdensitometric image analysis. Conclusions: GDNF added to the nerve graft favored the motor recovery, local neuronal fiber growth and neuroplasticity in the adjacent spinal cord.
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Objective: The impact of hormonal fluctuation during the menstrual cycle on the course of bipolar disorder is poorly understood. The authors determined the course of illness and time to relapse of bipolar disorder in prospectively followed women with premenstrual exacerbation. Method: Participants were 293 premenopause-age women with bipolar disorder who were followed prospectively for 1 year as part of the Systematic Treatment Enhancement Program for Bipolar Disorder. Frequency of mood episodes was compared between 191 women with premenstrual exacerbation (65.2%) and 102 women without. Among 129 women who were in recovered status at baseline, time to relapse was compared between 66 women with premenstrual exacerbation (51.2%) and 63 without. Results: During follow-up, the group with premenstrual exacerbation had more episodes (primarily depressive) than did the group without, but they were not more likely to meet criteria for rapid cycling during this period. In contrast, they were more likely to report rapid cycling retrospectively. Women with premenstrual exacerbation had a shorter time to relapse and were at greater risk for relapse, but this association was not significant after adjustment for retrospectively reported rapid cycling. Women with premenstrual exacerbation had more depressive and mood elevation symptoms overall. Conclusions: Women with bipolar disorder and premenstrual exacerbation have a worse course of illness, a shorter time to relapse, and greater symptom severity, but they are not more likely to meet criteria for rapid cycling. Premenstrual exacerbation may be a clinical marker predicting a more symptomatic and relapse-prone phenotype in reproductive-age women with bipolar disorder.
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Introduction: Body mass index (BMI) increase is an undesired effect associated with antipsychotics, and crucial for patients` global health and treatment compliance. We aimed to investigate the relation between BMI during olanzapine or halopericlol treatments and leptin, neuropeptide Y (NPY), adiponectin and lipid serum levels. Methods: In this 9-month, randomized and naturalist study, 34 male patients, 18 on olanzapine and 16 on haloperidol group were enrolled, all were under monotherapy. Patient outcome was evaluated with positive and negative syndrome scale (PANSS) at every 3-month period. In each visit, BMI, leptin, NPY, lipid, olanzapine or haloperidol levels were also monitored. Results and Discussion: Leptin levels positively correlated with BMI in olanzapine (r = 0.64, p < 0.001) and haloperidol (r = 0.73, p < 0.001) groups; only in olanzapine patients, the former also correlated with PANSS score (r = 0.54, p < 0.05). NPY levels negatively correlated with olanzapine levels (r = -0.65, p < 0.01). Adiponectin levels had not significantly varied. Conclusion: Antipsychotics probably interfere on leptin and NPY signalling ways and disturb these hormones in eating behaviour control.
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Introduction: Aripiprazole, a dopamine D(2) receptor partial agonist, has also partial agonist activity at serotonin (5-HT)(1A) receptors and antagonist activity at 5-HT(2A) receptors. Methods: In this 8-week, multicenter, randomized, parallel-group, open-label, flexible-dose study, patients diagnosed with schizophrenia or schizoaffective disorder were randomized to aripiprazole 15-30 mg/day or haloperidol 10-15 mg/day. Results: Patients treated with both aripiprazole and haloperidol improved from baseline in Positive and Negative Syndrome Scale total, positive, and negative scores as well as in Clinical Global Impressions scores (all P<.001). At the end of the study, the percentage of patients classified as responders-according to >= 40% reduction in the Positive and Negative Syndrome Scale negative subscale score-was significantly higher in the aripiprazole group (20%) than in the haloperidol group (0%) (P<.05). Additionally, a higher number of patients receiving haloperidol required more anticholinergic medications (P<.001) than aripiprazole-treated patients, whereas more aripiprazole (45.5%) than haloperidol-treated patients (12.9%) required benzodiazepines (P=.002). At endpoint, rates of preference of medication were higher in the aripiprazole group (63.2%) than in the haloperidol group (21.7%), as expressed by patients and caregivers (P=.001). Conclusion: Aripiprazole and haloperidol had similar efficacy in terms of reduction of overall psychopathology. Although aripiprazole has been demonstrated to be superior concerning negative symptoms and in terms of tolerability (extrapyramidal symptoms) and preferred by patients and caregivers than haloperidol, significantly more aripiprazole-treated patients required benzodiazepines.
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Tumour cells are known to be highly glycolytic, thus producing high amounts of lactic acid. Monocarboxylate transporters (MCTs), by promoting the efflux of the accumulating acids, constitute one of the most important mechanisms in the maintenance of tumour intracellular pH. Since data concerning MCT expression in colorectal carcinomas (CRC) are scarce and controversial, the present study aimed to assess the expressions of MCT1, 2, and 4 in a well characterized series of CRC and assess their role in CRC carcinogenesis. CRC samples (126 cases) were analyzed for MCT1, MCT2, and MCT4 immunoexpression and findings correlated with clinico-pathological parameters. Expression of all MCT isoforms in tumour cells was significantly increased when compared to adjacent normal epithelium. Remarkably, there was a significant gain of membrane expression for MCT1 and MCT4 and loss of plasma membrane expression for MCT2 in tumour cells. Plasma membrane expression of MCT1 was directly related to the presence of vascular invasion. This is the larger study on MCT expression in CRC and evaluates for the first time its clinico-pathological significance. The increased expression of these transporters suggests an important role in CRC, which might justify their use, especially MCT1 and MCT4, as targets in CRC drug therapy.
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Many eukaryotic proteins are posttranslationally modified by the esterification of cysteine thiols to long-chain fatty acids. This modification, protein palmitoylation, is catalyzed by a large family of palmitoyl acyltransferases that share an Asp-His-His-Cys Cys-rich domain but differ in their subcellular localizations and substrate specificities. In Trypanosoma brucei, the flagellated protozoan parasite that causes African sleeping sickness, protein palmitoylation has been observed for a few proteins, but the extent and consequences of this modification are largely unknown. We undertook the present study to investigate T. brucei protein palmitoylation at both the enzyme and substrate levels. Treatment of parasites with an inhibitor of total protein palmitoylation caused potent growth inhibition, yet there was no effect on growth by the separate, selective inhibition of each of the 12 individual T. brucei palmitoyl acyltransferases. This suggested either that T. brucei evolved functional redundancy for the palmitoylation of essential palmitoyl proteins or that palmitoylation of some proteins is catalyzed by a noncanonical transferase. To identify the palmitoylated proteins in T. brucei, we performed acyl biotin exchange chemistry on parasite lysates, followed by streptavidin chromatography, two-dimensional liquid chromatography-tandem mass spectrometry protein identification, and QSpec statistical analysis. A total of 124 palmitoylated proteins were identified, with an estimated false discovery rate of 1.0%. This palmitoyl proteome includes all of the known palmitoyl proteins in procyclic-stage T. brucei as well as several proteins whose homologues are palmitoylated in other organisms. Their sequences demonstrate the variety of substrate motifs that support palmitoylation, and their identities illustrate the range of cellular processes affected by palmitoylation in these important pathogens.
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Several studies support a genetic influence on obsessive-compulsive disorder (OCD) etiology. The role of glutamate as an important neurotransmitter affecting OCD pathophysiology has been supported by neuroimaging, animal model, medication, and initial candidate gene studies. Genes involved in glutamatergic pathways, such as the glutamate receptor, ionotropic, kainate 2 (GRIK2), have been associated with OCD in previous studies. This study examines GRIK2 as a candidate gene for OCD susceptibility in a family-based approach. Probands had full DSM-IV diagnostic criteria for OCD. Forty-seven OCD probands and their parents were recruited from tertiary care OCD specialty clinics from France and USA. Genotypes of single nucleotide polymorphism (SNP) markers and related haplotypes were analyzed using Haploview and FBAT software. The polymorphism at rs1556995 (P = 0.0027; permuted P-value = 0.03) was significantly associated with the presence of OCD. Also, the two marker haplotype rs1556995/rs1417182, was significantly associated with OCD (P = 0.0019, permuted P-value = 0.01). This study supports previously reported findings of association between proximal GRIK2 SNPs and OCD in a comprehensive evaluation of the gene. Further study with independent samples and larger sample sizes is required.
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Cells produce and use peptides in distinctive ways. In the present report, using isotope labeling plus semi-quantitative mass spectrometry, we evaluated the intracellular peptide profile of TAP1/beta 2m(-/-) (transporter associated with antigen-processing 1/beta 2 microglobulin) double-knockout mice and compared it with that of C57BL/6 wild-type animals. Overall, 92 distinctive peptides were identified, and most were shown to have a similar concentration in both mouse strains. However, some peptides showed a modest increase or decrease (similar to 2-fold), whereas a glycine-rich peptide derived from the C-terminal of neurogranin (KGPGPGGPGGAGGARGGAGGGPSGD) showed a substantial increase (6-fold) in TAP1/beta 2m(-/-) mice. Thus, TAP1 and beta 2microglobulin have a small influence on the peptide profile of neuronal tissue, suggesting that the presence of peptides derived from intracellular proteins in neuronal tissue is not associated with antigens of the class I major histocompatibility complex. Therefore, it is possible that these intracellular peptides play a physiological role.
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There is evidence of personality disorders in patients with juvenile myoclonic epilepsy (JME). To date, there have been no published quantitative studies on personality traits in JME. The aim of the work described here was to study a group of patients with JME and quantitatively measure personality traits. We evaluated 42 patients (mean age: 26.57 years, SD: 8.38) and 42 controls (mean age: 26.96, SD: 8.48) using a validated personality inventory, the Temperament and Character Inventory (TCI). We applied two scores, one for the Beck Depression Inventory and one for the State-Trait-Anxiety Inventory, as depression and anxiety may impact the performance of these patients on the TCI. We compared both groups on TCI scales using analysis of covariance with Beck Depression Inventory and State-Trait-Anxiety Inventory scores as covariates. Patients with JME obtained significantly higher scores on Novelty Seeking (P=0.001) and Harm Avoidance (P=0.002) and significantly lower scores on Self-Directedness (P=0.001). Patients with JME have a higher expression of impulsive personality traits that demand early recognition to avoid further consequences and facilitate social insertion, consequently avoiding future stigma. (C) 2011 Elsevier Inc. All rights reserved.
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Few case series studies have addressed the issue of treatment response in patients with obsessive-compulsive disorder (OCD) and comorbid post-traumatic stress disorder (PTSD), and there are no prospective studies addressing response to conventional treatment in OCD patients with a history of trauma (HT). The present study aimed to investigate, prospectively, the impact of HT or PTSD on two systematic, first-line treatments for OCD. Two hundred and nineteen non-treatment-resistant OCD outpatients were treated with either group cognitive-behavioral therapy (GCBT n = 147) or monotherapy with a selective serotonin reuptake inhibitor (SSRI n = 72). Presence of HT and PTSD were assessed at intake, as part of a broader clinical and demographical baseline characterization of the sample. Severity and types of OCD symptoms were assessed with the Yale-Brown Obsessive-Compulsive Scale (YBOCS) and the Dimensional YBOCS (DYBOCS), respectively. Depression and anxiety symptoms were measured with the Beck Depression Inventory (BDI) and the Beck Anxiety Inventory (BAI). Both treatments had 12-week duration. Treatment response was considered as a categorical [35% or greater reduction in baseline YBOCS scores plus a Clinical Global Impression-Improvement rating of better (2) or much better (1)] and continuous variable (absolute number reduction in baseline YBOCS scores). Treatment response was compared between the OCD + HT group versus the OCD without HT group and between the OCD + PTSD group versus the OCD without PTSD group. Parametric and non-parametric tests were used when indicated. Data on HT and PTSD were available for 215 subjects. Thirty-eight subjects (17.67% of the whole sample) had a positive HT (OCD + HT group) and 22 subjects (57.89% of the OCD + HT group and 10.23% of the whole sample) met full DSM-IV criteria for PTSD. The OCD + HT and OCD without HT groups presented similar response to GCBT (60% of responders in the first group and 63% of responders in the second group, p = 1.00). Regarding SSRI treatment, the difference between the response of the OCD + HT (47.4%) and OCD without HT (22.2%) groups was marginally significant (p = 0.07). In addition, the OCD + PTSD group presented a greater treatment response than the OCD without PTSD group when treatment response was considered as a continuous variable (p = 0.01). The age when the first trauma occurred had no impact on treatment response. In terms of specific OCD symptom dimensions, as measured by the DYBOCS, OCD treatment fostered greater reductions for the OCD + PTSD group than for the OCD without PTSD group in the scores of contamination obsessions and cleaning compulsions, collecting and hoarding and miscellaneous obsessions and related compulsions (including illness concerns and mental rituals, among others). The OCD + PTSD group also presented a greater reduction in anxiety scores than the OCD without PTSD group (p = 0.003). The presence of HT or PTSD was not related to a poorer treatment response in this sample of non-treatment-resistant OCD patients. Unexpectedly, OCD patients with PTSD presented a greater magnitude of response when compared with OCD without PTSD patients in specific OCD symptom dimensions. Future studies are needed to clarify if trauma and PTSD have a more significant impact on the onset and clinical expression of OCD than on the conventional treatment for this condition, and whether OCD stemming from trauma would constitute a subtype of OCD with a distinct response to conventional treatment.