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Brain-derived neurotrophic factor (BDNF), a member of the nerve-growth-factor family, plays an important role in neuronal survival and development, and it can modulate serotonergic activity. Further, BDNF has been implicated in the expression of personality traits and in cognitive function. We tested the associations between functional BDNF Val66Met genetic variants, and personality trait and intelligence in a cohort of 114 healthy young Chinese females. Subjects with the Val/Val genotype had a significantly higher mean performance IQ than Val/Met carriers, especially for the Object Assembly subtest. No significant association was demonstrated for the BDNF polymorphism and any of the Tridimensional Personality Questionnaire personality-factor scores, including harm avoidance. These results suggest that genetic variants of the BDNF gene may play a role in specific cognitive functions, but not in overall intelligence. In contrast to a recent report, however, this polymorphism does not appear to be associated with the neuroticism-related personality trait. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin growth factor family, has been implicated in both mood disorders and suicidal behavior. This study has examined the association between the BDNF gene Val66Met polymorphism and mood disorders, age of onset and suicidal behavior in a Chinese sample population. The genotype and allele frequencies for the BDNF gene Val66Met polymorphism did not differ comparing depression groups (total, bipolar disorder or major depression) and control subjects. Furthermore, it was not demonstrated that this BDNF polymorphism was associated with age of onset or suicidal history in our mood disorder patients. Based on these results, it seems reasonable to suggest that this polymorphism is unlikely to play a major role in the genetic susceptibility to mood disorders. Given the fact that the positive association between BDNF gene Val66Met polymorphism and bipolar disorder has only been demonstrated for a Caucasian population but not for a Japanese analog or our Chinese sample, it appears likely that this association is ethnicity dependent. Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Proinflammatory cytokines, including interleukin (IL)-1beta, are suggested to have a role in the pathogenesis of major depressive disorder (MDD) and be related to the therapeutic effects of antidepressants. To elucidate a genetic predisposition of MDD, we studied biallelic polymorphism in the promoter region (position -511) of the IL-1beta gene in 157 patients with MDD and in 112 controls. We also examined the association of this polymorphism and fluoxetine therapeutic response in 119 MDD patients who received a 4-week fluoxetine treatment. No significant difference was found in the genetic polymorphism between MDD patients and controls. However, MDD patients who were homozygous for the -511T allele of the IL-1beta gene had a trend of less severity of depressive symptoms and more favorable fluoxetine therapeutic response than -511C carriers. Further study with a larger sample is needed to clarify the role of the IL-1beta genetic polymorphisms in the symptoms and treatment effects in MDD. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Association Between Heart Rate Variability and Cognitive function in Elderly Community-Dwelling Men Without Dementia: A Preliminary Report."

Because of a decrease in central brain-derived neurotrophic factor (BDNF) levels in Alzheimer’s disease (AD) and the important role of BDNF in neuronal survival, BDNF may represent a candidate gene conferring susceptibility to AD. Recently, a functional BDNF Val66Met polymorphism has been associated with AD in an Italian population. In the present study, we investigated a possible role of this BDNF polymorphism in the susceptibility of AD or AD onset in a Chinese population. Comparing AD patients and controls, the distribution of the BDNF genotypes and alleles did not differ significantly. The onset age was not significantly different comparing the three BDNF genotype groups. Our negative findings suggest that it is unlikely that the BDNF Val66Met polymorphism plays a major role in the pathogenesis of AD in the Chinese population and do not support previous findings that homozygosity for the 66Val allele confers an increased risk for AD. Further studies with genetic variations in BDNF relating either to AD-associated depression or to the AD treatment response are suggested. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The article discusses Alzheimer's disease. Adenosine, a purine nucleoside, functions as a neuromodulator in the brain and is widely distributed throughout the central nervous system, with the highest densities in the hippocampus, the neocortex and the striatum. There is considerable evidence supporting the involvement of adenosine A2a receptor (A2aAR) in the pathogenesis of Alzheimer's disease (AD). Studies found that the intake of caffeine, an antagonist for the adenosine receptors, was inversely associated with AD risk, and the A2aAR may be the molecular target responsible for the observed beneficial effects of caffeine consumption in the development of AD.

Background: It is unclear whether the loss of physiological complexity during the aging process is due to genetic variations. The APOE gene has been studied extensively in regard to its relationship with aging-associated medical illness. We hypothesize that diminished physiological complexity, as measured by heart rate variability, is influenced by polymorphisms in the APOE allele among elderly individuals. Methodology/Principal Findings: A total of 102 robust, non-demented, elderly subjects with normal functions of daily activities participated in this study (97 males and 5 females, aged 79.2±4.4 years, range 72–92 years). Among these individuals, the following two APOE genotypes were represented: ε4 non-carriers (n = 87, 85.3%) and ε4 carriers (n = 15, 14.7%). Multi-scale entropy (MSE), an analysis used in quantifying complexity for nonlinear time series, was employed to analyze heart-rate dynamics. Reduced physiological complexity, as measured by MSE, was significantly associated with the presence of the APOE ε4 allele in healthy elderly subjects, as compared to APOE ε4 allele non-carriers (24.6±5.5 versus 28.9±5.2, F = 9.429, p = 0.003, respectively). Conclusions/Significance: This finding suggests a role for the APOE gene in the diminished physiological complexity seen in elderly populations. [ABSTRACT FROM AUTHOR]

Objective Panic disorder (PD) is characterized by panic attacks accompanied with respiratory symptoms. Internal jugular vein (IJV) alters its hemodynamics in response to respiration and which might cause cerebral blood flow (CBF) changes. In the present study, we compared (1) respiratory-related IJV hemodynamics and (2) CBF changes during Valsalva maneuver (VM) between PD and normal subjects. Methods 42 PD patients and age/gender-matched controls (14 men; 52.3 ± 11.4 years) were recruited. Duplex ultrasonography measured time-averaged mean velocity (TAMV) and lumen in IJV at baseline and deep inspiration. Lumen area <0.10 cm2 at deep inspiration was defined as IJV collapse. CBF changes during VM were recorded by transcranial Doppler (TCD). Results Compared with normal group, PD patients had significantly higher frequency of IJV collapse at deep inspiration (Left: 40.0% vs. 7.0%, p = 0.0003, Right: 17.0% vs. 0%, p = 0.0119). IJV collapse was associated with symptoms of respiratory subtype in our PD patients. PD group also had smaller lumen (Left: 0.53 ± 0.29 vs. 0.55 ± 0.26 cm2, p = 0.8296, Right: 0.63 ± 0.36 vs. 0.93 ± 0.45 cm2, p = 0.0014) and slower TAMV of IJV at baseline (Left: 11.8 ± 8.43 vs. 20.6 ± 16.5 cm/s, p = 0.0003, Right: 15.9 ± 9.19 vs. 24.1 ± 15.7 cm/s, p = 0.0062). PD patients with inspiration-induced IJV collapse had more decreased CBF during VM compared with the other PD patients and normal individuals respectively. Interpretation We are the first to show that PD have less IJV flow at baseline and more frequent collapse at deep inspiration. Inspiration-induced IJV collapsed was associated with CBF decrement during VM in PD patients. These results suggest that venous drainage impairment might play a role in the pathophysiology of PD by influencing CBF. [ABSTRACT FROM AUTHOR]

Objectives: The forced swim test (FST) is a commonly used model to predict antidepressant efficacy. Uncovering the genetic basis of the model may unravel the mechanism of antidepressant treatment. Methods: FVB/NJ (FVB) and C57BL/6J (B6) were first identified as the response and non-response strains to fluoxetine (a serotonin-specific reuptake inhibitor antidepressant) treatment in the mouse FST. Simple-interval (SIM) and compositeinterval (CIM) mappings were applied to map the quantitative trait loci (QTLs) of the anti-immobility effect of fluoxetine in FST (FSTFLX) in 865 male B66FVB-F2 mice. The brain mRNA expressions of the gene with the maximum QTL-linkage signal for FSTFLX after the FST were compared between B6 and FVB mice and also compared between fluoxetine and saline treatment. The association of the variants in the human homologue of the mouse FSTFLX-QTL gene with major depressive disorder (MDD) and antidepressant response were investigated in 1080 human subjects (MDD/control = 582/498). Results: One linkage signal for FSTFLX-QTL was detected at an intronic SNP (rs6215396) of the mouse Zfp326 gene (maximal CIM-LOD = 9.36). The Zfp326 mRNA expression in the FVB thalamus was significantly down-regulated by fluoxetine in the FST, and the higher FVB-to-B6 Zfp326 mRNA expressions in the frontal cortex, striatum and hypothalamus diminished after fluoxetine treatment. Two coding-synonymous SNPs (rs2816881 and rs10922744) in the human homologue of Zfp326, ZNF326, were significantly associated with the 8-week antidepressant treatment response in the MDD patients (Bonferronicorrected p = 0.004-0.028). [ABSTRACT FROM AUTHOR]

Background Reversible cerebral vasoconstriction syndrome (RCVS) could be complicated by cerebral ischemic events. Hypothetical mechanisms of RCVS involve endothelial dysfunction and sympathetic overactivity, both of which were reported to be related to brain-derived neurotrophic factor (BDNF). The study investigated the association between functional BDNF Val66Met polymorphism and RCVS. Methods Patients with RCVS and controls were prospectively recruited and genotyped for the BDNF Val66Met polymorphism. Magnetic resonance angiography (MRA) and transcranial color-coded Doppler sonography were employed to evaluate cerebral vasoconstriction. Genotyping results, clinical parameters, vasoconstriction scores, mean flow velocities of the middle cerebral artery (VMCA), and Lindegaard indices were analyzed. Split-sample approach was employed to internally validate the data. Principal Findings Ninety Taiwanese patients with RCVS and 180 age- and gender-matched normal controls of the same ethnicity completed the study. The genotype frequencies did not differ between patients and controls. Compared to patients with Met/Met homozygosity, patients with Val allele had higher mean vasoconstriction scores of all arterial segments (1.60±0.72 vs. 0.87±0.39, p<0.001), VMCA values (116.7±36.2 vs. 82.7±17.9 cm/s, p<0.001), and LI (2.41±0.91 vs. 1.89±0.41, p = 0.001). None of the Met/Met homozygotes, but 38.9% of the Val carriers, had VMCA values of >120 cm/s (p<0.001). Split-sample validation by randomization, age, entry time or residence of patients demonstrated concordant findings. Conclusions Our findings link BDNF Val66Met polymorphism with the severity of RCVS for the first time and implicate possible pathogenic mechanisms for vasoconstriction in RCVS. [ABSTRACT FROM AUTHOR]

Objectives: The correlation between anxiety and interstitial cystitis has, as best we know, not yet been reported on. The present study investigated the psychological profile, including anxiety and depression, of patients suffering from interstitial cystitis (IC). Methods: A total of 47 IC patients, all of whom met National Institute of Arthritis, Diabetes, Digestive and Kidney Diseases (NIDDK) criteria, plus a group of 31 age-matched, asymptomatic women received a structured interview on depression (Hamilton Rating Scale for Depression) and also on anxiety symptoms (Hamilton Rating Scale for Anxiety). IC patients also completed questionnaires relating to IC symptom severity, including urgency and frequency (visual analog scale) and O'Leary Sant index. Results: A total of 85% of our IC patients featured significant affective symptoms. The average depression scores were 16.6. Fifteen patients (31.9%) featured mild depressive symptoms, five (10.6%) had mild to moderate and 20 (42.6%) had moderate to severe depression symptoms. The mean anxiety score was 21.0, with 21 (44.7%), nine (19.1%) and 17 (36.2%) patients revealing mild, mild to moderate, and moderate to severe anxiety symptoms, respectively. Further, IC patients reported a significantly greater extent of depression and anxiety than was the case for controls. Pain scale and O'Leary Sant index were significantly correlated to anxiety and depression score. Conclusions: Most of our IC patients feature significant depression and anxiety. The extent of affective symptoms would appear to correlate well with IC symptom severity. [ABSTRACT FROM AUTHOR]