Smolders, R.; Rijpkema, M.J.P.; Franke, B.; Fernandez, G.S.E.
Brain-derived neurotrophic factor (BDNF) plays a critical role in brain development. A common single nucleotide polymorphism in the gene encoding BDNF (rs6265, Val66Met) affects BDNF release and has been associated with altered learning and memory performance, and with structural changes in brain mo
Jamal, Mumtaz; Van der Does, Willem; Elzinga, Bernet M.; Molendijk, Marc L.; Penninx, Brenda W. J. H.
Introduction: Nicotine use is associated with the upregulation of brain-derived neurotrophic factor (BDNF) in serum. An association between smoking and the BDNF Val(66)Met polymorphism has also been found. The aim of this study is to examine the levels of serum BDNF in never-smokers, former smokers,
Jing, Deqiang; Lee, Francis S; Ninan, Ipe
The Val66Met polymorphism in the brain-derived neurotrophic factor (BDNF) gene disrupts the activity-dependent release of BDNF, which might underlie its involvement in several neuropsychiatric disorders. Consistent with the potential role of regulated release of BDNF in synaptic functions, earlier studies have demonstrated that the BDNF Val66Met polymorphism impairs NMDA receptor-mediated synaptic transmission and plasticity in the hippocampus, the medial prefrontal cortex and the central amygdala. However, it is unknown whether the BDNF Val66Met polymorphism affects synapses in the dorsal striatum, which depends on cortical afferents for BDNF. Electrophysiological experiments revealed an enhanced glutamatergic transmission in the dorsolateral striatum (DLS) of knock-in mice containing the variant polymorphism (BDNF(Met/Met)) compared to the wild-type (BDNF(Val/Val)) mice. This increase in glutamatergic transmission is mediated by a potentiation in glutamate release and NMDA receptor transmission in the medium spiny neurons without any alterations in non-NMDA receptor-mediated transmission. We also observed an impairment of synaptic plasticity, both long-term potentiation and depression in the DLS neurons, in BDNF(Met/Met) mice. Thus, the BDNF Val66Met polymorphism exerts an increase in glutamatergic transmission but impairs synaptic plasticity in the dorsal striatum, which might play a role in its effect on neuropsychiatric symptoms. This article is part of the Special Issue entitled 'Ionotropic glutamate receptors'.
Chen, Zhe-Yu; Patel, Paresh D; Sant, Gayatree; Meng, Chui-Xiang; Teng, Kenneth K; Hempstead, Barbara L; Lee, Francis S
Brain-derived neurotrophic factor (BDNF) plays a critical role in nervous system and cardiovascular development and function. Recently, a common single nucleotide polymorphism in the bdnf gene, resulting in a valine to methionine substitution in the prodomain (BDNF(Met)), has been shown to lead to memory impairment and susceptibility to neuropsychiatric disorders in humans heterozygous for the variant BDNF. When expressed by itself in hippocampal neurons, less BDNF(Met) is secreted in an activity-dependent manner. The nature of the cellular defect when both BDNF(Met) and wild-type BDNF (BDNF(Val)) are present in the same cell is not known. Given that this is the predominant expression profile in humans, we examined the effect of coexpressed BDNF(Met) on BDNF(Val) intracellular trafficking and processing. Our data indicate that abnormal trafficking of BDNF(Met) occurred only in neuronal and neurosecretory cells and that BDNF(Met) could alter the intracellular distribution and activity-dependent secretion of BDNF(Val). We determined that, when coexpressed in the same cell, approximately 70% of the variant BDNF forms BDNF(Val).BDNF(Met) heterodimers, which are inefficiently sorted into secretory granules resulting in a quantitative decreased secretion. Finally, we determined the form of BDNF secreted in an activity-dependent manner and observed no differences in the forms of BDNF(Met) or the BDNF(Val).BDNF(Met) heterodimer compared with BDNF(Val). Together, these findings indicate that components of the regulated secretory machinery interacts specifically with a signal in the BDNF prodomain and that perturbations in BDNF trafficking may lead to selective impairment in CNS function.
Full Text Available Abstract Background Stress involves alterations of brain functioning that may precipitate to mood disorders. The neurotrophin Brain Derived Neurotrophic Factor (BDNF has recently been involved in stress-induced adaptation. BDNF is a key regulator of neuronal plasticity and adaptive processes. Regulation of BDNF is complex and may reflect not only stress-specific mechanisms but also hormonal and emotional responses. For this reason we used, as an animal model of stress, a fish whose brain organization is very similar to that of higher vertebrates, but is generally considered free of emotional reactions. Results We provide a comprehensive characterization of BDNF gene in the Dicentrarchus labrax and its transcriptional, translational and post-translational regulation following acute stress. While total BDNF mRNA levels are unchanged, BDNF transcripts 1c and 1d resulted down regulated after acute stress. Acute stress induces also a significant increase in proBDNF levels and reduction in mature BDNF suggesting altered regulation of proBDNF proteolytic processing. Notably, we provide here the first evidence that fishes possess a simplified proteolytic regulation of BDNF since the pro28Kda form, generated by the SKI-1 protease in mammals, is absent in fishes because the cleavage site has first emerged in reptilians. Finally, we show that the proBDNF/totBDNF ratio is a highly predictive novel quantitative biomarker to detect stress in fishes with sensitivity = 100%, specificity = 87%, and Negative Predictive Value = 100%. Conclusion The high predictivity of proBDNF/totBDNF ratio for stress in lower vertebrates indicates that processing of BDNF is a central mechanism in adaptation to stress and predicts that a similar regulation of pro/mature BDNF has likely been conserved throughout evolution of vertebrates from fish to man.
Mallei, A.; Baj, G.; Ieraci, A.; Corna, S.; Musazzi, L.; Lee, F S; Tongiorgi, E.; Popoli, M.
Background: The human Val66Met polymorphism in brain-derived neurotrophic factor (BDNF), a key factor in neuroplasticity, synaptic function, and cognition, has been implicated in the pathophysiology of neuropsychiatric and neurodegenerative disorders. BDNF is encoded by multiple transcripts with distinct regulation and localization, but the impact of the Val66Met polymorphism on BDNF regulation remains unclear. Methods: In BDNF Val66Met knock-in mice, which recapitulate the phenotypic hallmar...
Helm, Erin E; Tyrell, Christine M; Pohlig, Ryan T; Brady, Lucas D; Reisman, Darcy S
Induction of neural plasticity through motor learning has been demonstrated in animals and humans. Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family of growth factors, is thought to play an integral role in modulation of central nervous system plasticity during learning and motor skill recovery. Thirty percent of humans possess a single-nucleotide polymorphism on the BDNF gene (Val66Met), which has been linked to decreased activity-dependent release of BDNF. Presence of the polymorphism has been associated with altered cortical activation, short-term plasticity and altered skill acquisition, and learning in healthy humans. The impact of the Val66Met polymorphism on motor learning post-stroke has not been explored. The purpose of this study was to examine the impact of the Val66Met polymorphism in learning of a novel locomotor task in subjects with chronic stroke. It was hypothesized that subjects with the polymorphism would have an altered rate and magnitude of adaptation to a novel locomotor walking paradigm (the split-belt treadmill), compared to those without the polymorphism. The rate of adaptation was evaluated as the reduction in gait asymmetry during the first 30 (early adaptation) and last 100 (late adaptation) strides. Twenty-seven individuals with chronic stroke participated in a single session of split-belt treadmill walking and tested for the polymorphism. Step length and limb phase were measured to assess adaptation of spatial and temporal parameters of walking. The rate of adaptation of step length asymmetry differed significantly between those with and without the polymorphism, while the amount of total adaptation did not. These results suggest that chronic stroke survivors, regardless of presence or absence of the polymorphism, are able to adapt their walking pattern over a period of trial-and-error practice; however, the presence of the polymorphism influences the rate at which this is achieved.
Full Text Available Liang-Jen Wang,1,* Chih-Ken Chen,2,3,* Heng-Jung Hsu,3,4 I-Wen Wu,3,4 Chiao-Yin Sun,3,4 Chin-Chan Lee3,41Department of Child and Adolescent Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan; 2Department of Psychiatry, Chang Gung Memorial Hospital, Keelung, Taiwan; 3Chang Gung University School of Medicine, Taoyuan, Taiwan; 4Department of Nephrology, Chang Gung Memorial Hospital, Keelung, Taiwan *LJW and CKC are joint first authors and contributed equally to this manuscriptObjective: Depression is the most prevalent comorbid psychiatric disease among hemodialysis patients with end-stage renal disease. This cross-sectional study investigated whether depression in hemodialysis patients is associated with the polymorphism of the 5' flanking transcriptional region (5-HTTLPR of the serotonin transporter gene, the valine (Val-to-methionine (Met substitution at codon 66 (Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF gene, or plasma BDNF levels.Methods: A total of 188 participants (mean age: 58.5±14.0 years; 89 men and 99 women receiving hemodialysis at the Chang Gung Memorial Hospital were recruited. The diagnosis of major depressive disorder (MDD was confirmed using the Chinese version of the Mini International Neuropsychiatric Interview. The genotypes of 5-HTTLPR and BDNF Val66Met were conducted using polymerase chain reactions plus restriction fragment length polymorphism analysis. The plasma BDNF levels were measured using an enzyme-linked immunosorbent assay kit.Results: Forty-five (23.9% patients fulfilled the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV-TR criteria for a MDD. There were no significant effects of the 5-HTTLPR or BDNF Val66Met gene polymorphism on MDD among the hemodialysis patients. The plasma BDNF levels correlated significantly with age (P=0.003 and sex (P=0.047 but not with depression, the genotypes of 5
Qin, Luye; Jing, Deqiang; Parauda, Sarah; Carmel, Jason; Ratan, Rajiv R; Lee, Francis S; Cho, Sunghee
Little is known about the influence of genetic diversity on stroke recovery. One exception is the polymorphism in brain derived neurotrophic factor (BDNF), a critical neurotrophin for brain repair and plasticity. Humans have a high-frequency single nucleotide polymorphism (SNP) in the prodomain of the BDNF gene. Previous studies show that the BDNF Val66Met variant negatively affects motor learning and severity of acute stroke. To investigate the impact of this common BDNF SNP on stroke recovery, we used a mouse model that contains the human BDNF Val66Met variant in both alleles (BDNF(M/M)). Male BDNF(+/+) and BDNF(M/M) littermates received sham or transient middle cerebral artery occlusion. We assessed motor function regularly for 6 months after stroke and then performed anatomical analyses. Despite reported negative association of the SNP with motor learning and acute deficits, we unexpectedly found that BDNF(M/M) mice displayed significantly enhanced motor/kinematic performance in the chronic phase of motor recovery, especially in ipsilesional hindlimb. The enhanced recovery was associated with significant increases in striatum volume, dendritic arbor, and elevated excitatory synaptic markers in the contralesional striatum. Transient inactivation of the contralateral striatum during recovery transiently abolished the enhanced function. This study showed an unexpected benefit of the BDNFVal66Met carriers for functional recovery, involving structural and molecular plasticity in the nonstroked hemisphere. Clinically, this study suggests a role for BDNF genotype in predicting stroke recovery and identifies a novel systems-level mechanism for enhanced motor recovery.
Ninan, Ipe; Bath, Kevin G; Dagar, Karishma; Perez-Castro, Rosalia; Plummer, Mark R; Lee, Francis S; Chao, Moses V
The Val66Met polymorphism in the brain-derived neurotrophic factor (BDNF) gene results in a defect in regulated release of BDNF and affects episodic memory and affective behaviors. However, the precise role of the BDNF Val66Met polymorphism in hippocampal synaptic transmission and plasticity has not yet been studied. Therefore, we examined synaptic properties in the hippocampal CA3-CA1 synapses of BDNF(Met/Met) mice and matched wild-type mice. Although basal glutamatergic neurotransmission was normal, both young and adult mice showed a significant reduction in NMDA receptor-dependent long-term potentiation. We also found that NMDA receptor-dependent long-term depression was decreased in BDNF(Met/Met) mice. However, mGluR-dependent long-term depression was not affected by the BDNF Val66Met polymorphism. Consistent with the NMDA receptor-dependent synaptic plasticity impairment, we observed a significant decrease in NMDA receptor neurotransmission in the CA1 pyramidal neurons of BDNF(Met/Met) mice. Thus, these results show that the BDNF Val66Met polymorphism has a direct effect on NMDA receptor transmission, which may account for changes in synaptic plasticity in the hippocampus.
Full Text Available Abstract Background Brain-Derived Neurotrophic Factor (BDNF is a neurotrophin which plays survival- and growth-promoting activity in neuronal cells and it is involved in cellular plasticity mechanisms as it controls activity dependent synaptic transmission. A functional polymorphism (Val66Met in the pro-region of BDNF, which affects the intracellular trafficking of proBDNF has been associated with memory and cognitive deficits as well as to an increased susceptibility for several psychiatric disorders especially those with a neurodevelopmental origin. To date, no study has evaluated the influence of the Val66Met polymorphism on BDNF levels in a peripheral system that may reflect fetal neurodevelopment. Therefore we investigated in amniotic fluids (AF obtained from 139 healthy women during 15-17 week of pregnancy, BDNF protein levels in correlation with the Val66Met polymorphism. Results Interestingly we found a significant BDNF protein levels reduction in 55 Met carriers (Val/Met and Met/Met (p = 0.002 as compared to 84 non carriers (Val/Val, and no effect of fetus gender, maternal age or gestation week on BDNF levels has been observed. Conclusion These results, although explorative, indicate that during fetal life the Val66Met genotype might influences BDNF protein levels in AF supporting the involvement of this polymorphism in behavioral and functional brain individual differences in the adulthood.
Vinberg, Maj; Bukh, Jens Otto Drachmann; Bennike, Bente;
Brain derived neurotrophic factor (BDNF) seems to play an important role in the pathophysiology of affective disorders. The current study investigated whether blood level BDNF is correlated with the severity of depressive symptoms and recent (six months prior to onset of depression) experience......). Symptomatology was rated using Hamilton Rating Scale for Depression (HAMD-17) and Becks Depression Inventory (BDI 21). No differences in whole blood BDNF was seen in relation to the BDNF Val66Met polymorphism and no significant correlations between whole blood BDNF and HAMD-17 or BDI 21 scores were found....... No significant associations between the experiences of SLE before onset of depression and BDNF level were observed. Finally, peripheral BDNF differentiated between patients and healthy control persons. In the current sample of first episode depressed patients, the Val66Met polymorphism was not associated...
Klein, Anders Bue; Trajkovska, Viktorija; Erritzoe, David;
Recent studies have proposed an interrelation between the brain-derived neurotrophic factor (BDNF) val66met polymorphism and the serotonin system. In this study, we investigated whether the BDNF val66met polymorphism or blood BDNF levels are associated with cerebral 5-hydroxytryptamine 2A (5-HT(2A......)) receptor or serotonin transporter (SERT) binding in healthy subjects. No statistically significant differences in 5-HT(2A) receptor or SERT binding were found between the val/val and met carriers, nor were blood BDNF values associated with SERT binding or 5-HT(2A) receptor binding. In conclusion, val66met...... BDNF polymorphism status is not associated with changes in the serotonergic system. Moreover, BDNF levels in blood do not correlate with either 5-HT(2A) or SERT binding....
Montag, C.; Basten, U.; Stelzel, C.; Fiebach, C.J.; Reuter, M.
Although the brain derived neurotrophic factor (BDNF) has been mainly investigated in the context of depression and anxiety disorders, several studies also suggest an association between BDNF and smoking. BDNF represents a protein which crucially influences several processes in the cell ranging from
Chang, Chuan-Chia; Chang, Hsin-An; Chen, Tien-Yu; Fang, Wen-Hui; Huang, San-Yuan
The Val/Val genotype of the brain-derived neurotrophic factor (BDNF) polymorphism (Val66Met) has been reported to affect human anxiety-related phenotypes. Substantial research has demonstrated that anxiety is associated with sympathetic activation, while sex steroid hormones have been shown to exert differential actions in regulating BDNF expression. Thus, we examined whether the BDNF variant modulates autonomic function in a gender-dependent manner. From 708 adults initially screened for medical and psychiatric illnesses, a final cohort of 583 drug-free healthy Han Chinese (355 males, 228 females; age 34.43±8.42 years) was recruited for BDNF genotyping (Val/Val: 136, 23.3%, Val/Met: 294, 50.4%, and Met/Met: 153, 26.2%). Time- and frequency-domain analyses of heart rate variability (HRV) were used to assess autonomic outflow to the heart. Significant genotype-by-gender interaction effects were found on HRV indices. Even after adjusting for possible confounders, male participants bearing the Val/Val genotype had significant increases in low frequency (LF), LF% and LF/high frequency (HF) ratio, indicating altered sympathovagal balance with increased sympathetic modulation, compared to male Met/Met homozygotes. Females, however, showed an opposite but non-significant pattern. These results suggest that the studied BDNF polymorphism is associated with sympathetic control in a gender-specific way. The findings here support the view that male subjects with the Val/Val genotype have increased risk of anxiety by association with sympathetic activation.
Full Text Available Empathy is an important driver of human social behaviors and presents genetic roots that have been studied in neuroimaging using the intermediate phenotype approach. Notably, the Val66Met polymorphism of the Brain-derived neurotrophic factor (BDNF gene has been identified as a potential target in neuroimaging studies based on its influence on emotion perception and social cognition, but its impact on self-reported empathy has never been documented. Using a neurogenetic approach, we investigated the association between the BDNF Val66Met polymorphism and self-reported empathy (Davis' Interpersonal Reactivity Index; IRI in a sample of 110 young adults. Our results indicate that the BDNF genotype is significantly associated with the linear combination of the four facets of the IRI, one of the most widely used self-reported empathy questionnaire. Crucially, the effect of BDNF Val66Met goes beyond the variance explained by two polymorphisms of the oxytocin transporter gene previously associated with empathy and its neural underpinnings (OXTR rs53576 and rs2254298. These results represent the first evidence suggesting a link between the BDNF gene and self-reported empathy and warrant further studies of this polymorphism due to its potential clinical significance.
Taschereau-Dumouchel, Vincent; Hétu, Sébastien; Bagramian, Anaït; Labrecque, Alexandre; Racine, Marion; Chagnon, Yvon C; Jackson, Philip L
Empathy is an important driver of human social behaviors and presents genetic roots that have been studied in neuroimaging using the intermediate phenotype approach. Notably, the Val66Met polymorphism of the Brain-derived neurotrophic factor (BDNF) gene has been identified as a potential target in neuroimaging studies based on its influence on emotion perception and social cognition, but its impact on self-reported empathy has never been documented. Using a neurogenetic approach, we investigated the association between the BDNF Val66Met polymorphism and self-reported empathy (Davis' Interpersonal Reactivity Index; IRI) in a sample of 110 young adults. Our results indicate that the BDNF genotype is significantly associated with the linear combination of the four facets of the IRI, one of the most widely used self-reported empathy questionnaire. Crucially, the effect of BDNF Val66Met goes beyond the variance explained by two polymorphisms of the oxytocin transporter gene previously associated with empathy and its neural underpinnings (OXTR rs53576 and rs2254298). These results represent the first evidence suggesting a link between the BDNF gene and self-reported empathy and warrant further studies of this polymorphism due to its potential clinical significance.
Full Text Available Brain-derived neurotrophic factor (BDNF has been suggested to play a major role in plasticity, neurogenesis and learning in the adult brain. The BDNF gene contains a common val66met polymorphism associated with decreased activity-dependent excretion of BDNF and a potential influence on behaviour, more specifically, on motor learning. The objective of this study was to determine the influence of the BDNF val66met polymorphism on short-term implicit associative learning and whether its influence is cognitive domain-specific (motor vs. language. A sample of 38 young healthy participants was genotyped, screened for background and neuropsychological differences, and tested with two associative implicit learning paradigms in two different cognitive domains, i.e., motor and vocabulary learning. Subjects performed the serial reaction time task (SRTT to determine implicit motor learning and a recently established associative vocabulary learning task (AVL for implicit learning of action and object words. To determine the influence of the BDNF polymorphism on domain-specific implicit learning, behavioural improvements in the two tasks were compared between val/val (n = 22 and met carriers (val/met: n = 15 and met/met: n = 1. There was no evidence for an impact of the BDNF val66met polymorphism on the behavioural outcome in implicit short-term learning paradigms in young healthy subjects. Whether this polymorphism plays a relevant role in long-term training paradigms or in subjects with impaired neuronal plasticity or reduced learning capacity, such as aged individuals, demented patients or patients with brain lesions, has to be determined in future studies.
Suchanek, Renata; Owczarek, Aleksander; Kowalski, Jan
Brain-derived neurotrophic factor (BDNF) is one of the candidate genes for schizophrenia. Polymorphism C-281A (rs28383487) in BDNF gene leads to the reduction of promoter activity in the hippocampal neurons in vitro. To our knowledge, this is the first study to examine the influence of alleles and genotypes of BDNF C-281A polymorphism on development, as well as the clinical course (age of onset, suicidal behaviour and psychopathology) of paranoid schizophrenia. The psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS) as subscale scores and also single-item scores. We have also performed the haplotype analysis with val66met BDNF polymorphism, which is known to be involved in the pathogenesis of schizophrenia. We have not found significant differences in the distribution of genotypes and alleles between schizophrenic patients and controls in both the overall analysis, as well as sex stratified. Also, we have not shown statistically significant differences between genotype groups and PANSS scale. However, an association between C-281A polymorphism and time of the first episode of paranoid schizophrenia was revealed. Genotype C/A had been connected with later age of onset of paranoid schizophrenia in men but not in women (p schizophrenia group compared to the controls.
Kokaeva, Z G; Kochetkova, T O; Afonchikova, E V; Kondratyeva, N S; Klimov, E A
Recent studies showed that brain-derived neurotrophic factor (BDNF) can participate in pathogenesis of various CNS disorders, being connected with proliferation, differentiation, and survival of neurons. In present study, analysis of occurrence rate was performed for three single nucleotide polymorphisms (SNPs) located in BDNF gene (rs6267 (A/G) allele A-0.265; rs2049046 (A/T) allele A-0.407; rs11030107 (A/G) allele A-0.872) in randomized selection of Moscow citizens. Linkage disequilibrium of rs6165 and rs2049046 loci was shown. Differences in allele frequencies in studied selection and populations of other re- gions were discovered.
Smits, J.A.J.; Powers, M.B.; Rosenfield, D.; Zvolensky, M.J.; Jacquart, J.; Davis, M.L.; Beevers, C.G.; Marcus, B.H.; Church, T.S.; Otto, M.W.
Background: Exercise interventions facilitate the odds of quit success among high-anxiety sensitive adults smokers. We examined the dependency of these benefits on the genetic BDNF Val66Met (rs6265) polymorphism; individuals who are Met carriers have lower BDNF responses and reduced associated benef
Warburton, Alix; Miyajima, Fabio; Shazadi, Kanvel; Crossley, Joanne; Johnson, Michael R; Marson, Anthony G; Baker, Gus A; Quinn, John P; Sills, Graeme J
Cognitive dysfunction is a common comorbidity in people with epilepsy, but its causes remain unclear. It may be related to the etiology of the disorder, the consequences of seizures, or the effects of antiepileptic drug treatment. Genetics may also play a contributory role. We investigated the influence of variants in the genes encoding neuron-restrictive silencer factor (NRSF) and brain-derived neurotrophic factor (BDNF), proteins previously associated with cognition and epilepsy, on cognitive function in people with newly diagnosed epilepsy. A total of 82 patients who had previously undergone detailed neuropsychological assessment were genotyped for single nucleotide polymorphisms (SNPs) across the NRSF and BDNF genes. Putatively functional SNPs were included in a genetic association analysis with specific cognitive domains, including memory, psychomotor speed, and information processing. Cross-sectional and longitudinal designs were used to explore genetic influences on baseline cognition at diagnosis and change from baseline over the first year since diagnosis, respectively. We found a statistically significant association between genotypic variation and memory function at both baseline (NRSF: rs1105434, rs2227902 and BDNF: rs1491850, rs2030324, rs11030094) and in our longitudinal analysis (NRSF: rs2227902 and BDNF: rs12273363). Psychomotor speed was also associated with genotype (NRSF rs3796529) in the longitudinal assessment. In line with our previous work on general cognitive function in the healthy aging population, we observed an additive interaction between risk alleles for the NRSF rs2227902 (G) and BDNF rs6265 (A) polymorphisms which was again consistent with a significantly greater decline in delayed recall over the first year since diagnosis. These findings support a role for the NRSF-BDNF pathway in the modulation of cognitive function in patients with newly diagnosed epilepsy.
Kirk I Erickson
Full Text Available Genetic variability in the dopaminergic and neurotrophic systems could contribute to age-related impairments in executive control and memory function. In this study we examined whether genetic polymorphisms for catechol-O-methyltransferase (COMT and brain-derived neurotrophic factor (BDNF were related to the trajectory of cognitive decline occurring over a 10-year period in older adults. A single-nucleotide polymorphism (SNP in the COMT (Val158/108Met gene affects the concentration of dopamine in the prefrontal cortex. In addition, a Val/Met substitution in the pro-domain for BDNF (Val66Met affects the regulated secretion and trafficking of BDNF with Met carriers showing reduced secretion and poorer cognitive function. We found that impairments over the 10-year span on a task-switching paradigm did not vary as a function of the COMT polymorphism. However, for the BDNF polymorphism the Met carriers performed worse than Val homozygotes at the first testing session but only the Val homozygotes demonstrated a significant reduction in performance over the 10-year span. Our results argue that the COMT polymorphism does not affect the trajectory of age-related executive control decline, whereas the Val/Val polymorphism for BDNF may promote faster rates of cognitive decay in old age. These results are discussed in relation to the role of BDNF in senescence and the transforming impact of the Met allele on cognitive function in old age.
Blanco, Y; Gómez-Choco, M; Arostegui, J L; Casanova, B; Martínez-Rodríguez, J E; Boscá, I; Munteis, E; Yagüe, J; Graus, F; Saiz, A
Brain-derived neurotrophic factor (BDNF), a neurotrophin produced by neurons and immune cells, promotes neuronal survival and repair during development and after CNS injury. The BDNF-Val66Met polymorphism is functional and induces abnormal intracellular trafficking and decreased BDNF release. Therefore, we investigated the impact of the BDNF-Val66Met polymorphism on the susceptibility and clinical course in a case-control study of 224 multiple sclerosis (MS) Spanish patients and 177 healthy controls. We found no evidence for association to susceptibility or severity of the disease in our population. Moreover, we did not observe, in a subgroup of 12 MS patients, that the methionine substitution at position 66 in the prodomain had negative impact in the capacity to produce BDNF by peripheral blood mononuclear cells (PBMC).
Jasińska, Kaja K; Molfese, Peter J; Kornilov, Sergey A; Mencl, W Einar; Frost, Stephen J; Lee, Maria; Pugh, Kenneth R; Grigorenko, Elena L; Landi, Nicole
Understanding how genes impact the brain's functional activation for learning and cognition during development remains limited. We asked whether a common genetic variant in the BDNF gene (the Val66Met polymorphism) modulates neural activation in the young brain during a critical period for the emergence and maturation of the neural circuitry for reading. In animal models, the bdnf variation has been shown to be associated with the structure and function of the developing brain and in humans it has been associated with multiple aspects of cognition, particularly memory, which are relevant for the development of skilled reading. Yet, little is known about the impact of the Val66Met polymorphism on functional brain activation in development, either in animal models or in humans. Here, we examined whether the BDNF Val66Met polymorphism (dbSNP rs6265) is associated with children's (age 6-10) neural activation patterns during a reading task (n = 81) using functional magnetic resonance imaging (fMRI), genotyping, and standardized behavioral assessments of cognitive and reading development. Children homozygous for the Val allele at the SNP rs6265 of the BDNF gene outperformed Met allele carriers on reading comprehension and phonological memory, tasks that have a strong memory component. Consistent with these behavioral findings, Met allele carriers showed greater activation in reading-related brain regions including the fusiform gyrus, the left inferior frontal gyrus and left superior temporal gyrus as well as greater activation in the hippocampus during a word and pseudoword reading task. Increased engagement of memory and spoken language regions for Met allele carriers relative to Val/Val homozygotes during reading suggests that Met carriers have to exert greater effort required to retrieve phonological codes.
Mehmet Bülent Sönmez
Full Text Available Background and Objectives: Brain-derived neurotrophic factor (BDNF and glial cell line-derived neurotrophic factor (GDNF are neurotrophic neuropeptides that play important roles in the synaptic plasticity, neuronal growth, survival and function. A possible neuroprotective role of neurotrophic factors against alcohol-induced cell damage has been suggested, and dysregulations in neurotrophic factors may be involved in the vulnerability to addiction. The aim of this study was to investigate the alterations of BDNF and GDNF serum levels in alcohol-addicted patients during alcohol withdrawal compared to healthy controls. Methods: BDNF and GDNF serum levels of 34 male inpatients diagnosed with alcohol addiction according to DSM-IV-TR were investigated during alcohol withdrawal (day 1, 7 and 14 in comparison to 32 healthy controls using an enzyme-linked immunosorbent assay (ELISA. Severity of alcohol withdrawal was measured by Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar, and intensity of alcohol craving was measured by Penn Alcohol Craving Scale (PACS during alcohol withdrawal (day 1, 7 and 14. Results: BDNF serum levels increased significantly during alcohol withdrawal (p = 0.020. They were negatively correlated to the severity of alcohol withdrawal, and the correlation was close to being statistically significant (p = 0.058. BDNF and GDNF serum levels did not differ significantly between the patient and control groups. GDNF serum levels did not change significantly during alcohol withdrawal. Conclusions: Our results may provide support for the previously hypothesized role of BDNF in the neuroadaptation during alcohol withdrawal.
Brandys, Marek K.; Kas, Martien J. H.; van Elburg, Annemarie A.; Ophoff, Roel; Slof-Op't Landt, Margarita C. T.; Middeldorp, Christel M.; Boomsma, Dorret I.; van Furth, Eric F.; Slagboom, P. Eline; Adan, Roger A. H.
Objectives. The Val66Met polymorphism (rs6265) of the BDNF gene is a non-synonymous polymorphism, previously associated with anorexia nervosa (AN). Methods. We genotyped rs6265 in 235 patients with AN and 643 controls. Furthermore, we performed a systematic review of all case-control and family-base
Kretschmer, Tina; Vitaro, Frank; Barker, Edward D
Peer antisocial behavior robustly predicts adolescents' own behavior but not all adolescents are equally vulnerable to their peers' influence and genetic factors may confer vulnerability. This study used data of n = 3081 adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC) to examine whether BDNF, a polymorphism that affects psychological functioning, moderates the association between affiliation with aggressive peers at age 10 and own aggression at age 15. A significant gene-environment interaction was found, where those who affiliated with aggressive peers in childhood showed increased risk for being aggressive in adolescence if they carried the BDNF met-met variant compared to val-val carriers. Our findings underline the importance of both biological and social factors for adolescent development.
Chen, Shiou-Lan; Lee, Sheng-Yu; Chang, Yun-Hsuan; Wang, Tzu-Yun; Chen, Shih-Heng; Chu, Chun-Hsien; Chen, Po See; Yang, Yen Kuang; Hong, Jau-Shyong; Lu, Ru-Band
BDNF and its gene polymorphism may be important in synaptic plasticity and neuron survival, and may become a key target in the physiopathology of long-term heroin use. Thus, we investigated the relationships between brain-derived neurotrophic factor (BDNF) plasma concentrations and the BDNF Val66Met nucleotide polymorphism (SNP) in heroin-dependent patients. The pretreatment expression levels of plasma BDNF and the BDNF Val66Met SNP in 172 heroin-dependent patients and 102 healthy controls were checked. BDNF levels were significantly lower in patients (F = 52.28, p BDNF levels significantly different between Met/Met, Met/Val, and Val/Val carriers in each group, which indicated that the BDNF Val66Met SNP did not affect plasma BDNF levels in our participants. In heroin-dependent patients, plasma BDNF levels were negatively correlated with the length of heroin dependency. Long-term (>15 years) users had significantly lower plasma BDNF levels than did short-term (BDNF concentration in habitual heroin users are not affected by BDNF Val66Met gene variants, but by the length of the heroin dependency.
Full Text Available Single nucleotide polymorphisms (SNPs are important markers which can be used in association studies searching for susceptible genes of complex diseases. High-throughput methods are needed for SNP genotyping in a large number of samples. In this study, we applied polyacrylamide gel-based microarray combined with dual-color hybridization for association study of four BDNF polymorphisms with autism. All the SNPs in both patients and controls could be analyzed quickly and correctly. Among four SNPs, only C270T polymorphism showed significant differences in the frequency of the allele (χ2 = 7.809, p = 0.005 and genotype (χ2 = 7.800, p = 0.020. In the haplotype association analysis, there was significant difference in global haplotype distribution between the groups (χ2 = 28.19，p = 3.44e-005. We suggest that BDNF has a possible role in the pathogenesis of autism. The study also show that the polyacrylamide gel-based microarray combined with dual-color hybridization is a rapid, simple and high-throughput method for SNPs genotyping, and can be used for association study of susceptible gene with disorders in large samples.
Manning, Elizabeth E; van den Buuse, Maarten
Growing clinical evidence suggests that persistent psychosis which occurs in methamphetamine users is closely related to schizophrenia. However, preclinical studies in animal models have focussed on psychosis-related behaviours following methamphetamine, and less work has been done to assess endophenotypes relevant to other deficits observed in schizophrenia. Altered social behaviour is a feature of both the negative symptoms and cognitive deficits in schizophrenia, and significantly impacts patient functioning. We recently found that brain-derived neurotrophic factor (BDNF) heterozygous mice show disrupted sensitization to methamphetamine, supporting other work suggesting an important role of this neurotrophin in the pathophysiology of psychosis and the neuronal response to stimulant drugs. In the current study, we assessed social and cognitive behaviours in methamphetamine-treated BDNF heterozygous mice and wildtype littermate controls. Following chronic methamphetamine exposure male wildtype mice showed a 50% reduction in social novelty preference. Vehicle-treated male BDNF heterozygous mice showed a similar impairment in social novelty preference, with a trend for no further disruption by methamphetamine exposure. Female mice were unaffected in this task, and no groups showed any changes in sociability or short-term spatial memory. These findings suggest that chronic methamphetamine alters behaviour relevant to disruption of social cognition in schizophrenia, supporting other studies which demonstrate a close resemblance between persistent methamphetamine psychosis and schizophrenia. Together these findings suggest that dynamic regulation of BDNF signalling is necessary to mediate the effects of methamphetamine on behaviours relevant to schizophrenia.
Getzmann, Stephan; Gajewski, Patrick D; Hengstler, Jan G; Falkenstein, Michael; Beste, Christian
Aging affects the ability to focus attention on a given task and to ignore distractors. These functions subserve response control processes for which fronto-striatal networks have been shown to play an important role. Within these networks, the brain-derived-neurotrophic-factor (BDNF), which is known to underlie aging effects, plays a pivotal role. We investigated how cognitive subprocesses constituting a cycle of distraction, orientation and refocusing of attention are affected by the functional BDNF Val66Met polymorphism using event-related potentials (ERPs) in 122 healthy elderly. Using an auditory distraction paradigm we found that the Val/Val genotype confers a disadvantage to its carriers. This disadvantage was partly compensated by intensified attentional shifting mechanisms. It could be based on response selection processes being more vulnerable against interference from distractors in this genotype group. Processes reflecting transient sensory memory processes, or the re-orientation of attention were not affected by the BDNF Val66Met polymorphism, suggesting a higher importance of BDNF for mechanisms related to response control, than stimulus processing. The results add on recent literature showing that the Met allele confers some benefit to its carriers. We suggest an account for unifying different results of BDNF Val66Met association studies in executive functions, based on the role of BDNF in fronto-striatal circuits.
Gajewski, Patrick D; Hengstler, Jan G; Golka, Klaus; Falkenstein, Michael; Beste, Christian
Aging is accompanied by impairments of executive functions that rely on the functional integrity of fronto-striatal networks. This integrity is modulated by the release of neurotrophins like the brain-derived-neurotrophic factor (BDNF). Here, we investigate effects of the functional BDNF Val66Met polymorphism on interference processing in 131 healthy elderly subjects using event-related potentials (ERPs). In a Stroop task, participants had to indicate the name or the colour of colour-words while colour was either compatible or incompatible with the name. We show that susceptibility to Stroop-interference is affected by the BDNF Val66Met polymorphism: the Met-allele carriers showed better performance and enhanced N450 in interference trials. Other processes necessary to prepare and allocate cognitive resources to a particular task were not affected by BDNF Val66Met polymorphism, underlining the specificity of the observed effects. The observed performance and ERP difference is possibly due to dopamine related effects of BDNF in fronto-striatal networks, where it putatively mediates a shift in the balance of the direct and indirect pathway involved in inhibitory functions.
Rostami, Elham; Krueger, Frank; Plantman, Stefan; Davidsson, Johan; Agoston, Denes; Grafman, Jordan; Risling, Mårten
The evidence that BDNF is involved in neuroprotection, neuronal repair and recovery after traumatic brain injury (TBI) is substantial. We have previously shown that the polymorphism of the human BDNF gene predicts cognitive recovery and outcome following penetrating TBI. The distribution of expression of BDNF and its receptors after penetrating TBI has not been investigated. In this study we examined the expression of these genes in a rat model of penetrating TBI. The injury is produced by a controlled penetration of a 2mm thick needle-shaped object, which is accelerated with a pellet from an air gun. We used in situ hybridization and investigated the mRNA expression of BDNF and its receptors: the full-length and the truncated TrkB and p75(NTR), from 1 day to 8 weeks following penetrating TBI. In addition, the protein level of BDNF in frontal cortex and hippocampus was measured by reverse phase protein microarray (RPPM). The mRNA expression of BDNF and its receptors decreased in the hippocampus in the border zone ipsilateral to the injury while there was an increase in mRNA expression at the contralateral side. The increase in BDNF mRNA expression in the hippocampus was sustained for 2 weeks following injury, with the highest expression noted in the CA3 cell layer. Furthermore, the protein analysis by RPPM showed increased levels of BDNF in the frontal cortex and the hippocampus up to 2 weeks after TBI. At 8 weeks following injury there was an intense labeling of the truncated TrkB receptor and the p75(NTR) in the area surrounding the cavity. Our study is the first report on the expression of BDNF and its receptors following penetrating TBI and suggests that their expression is altered long after the acute phase of injury. Further studies are needed to investigate if the late expressions of these receptors are beneficial or deleterious. In either case it indicates the possibility to influence the recovery after brain injury during the chronic phase and the
Dodds, Chris M; Henson, Richard N; Suckling, John;
It has been suggested that the BDNF Val66Met polymorphism modulates episodic memory performance via effects on hippocampal neural circuitry. However, fMRI studies have yielded inconsistent results in this respect. Moreover, very few studies have examined the effect of met allele load on activation...... of memory circuitry. In the present study, we carried out a comprehensive analysis of the effects of the BDNF polymorphism on brain responses during episodic memory encoding and retrieval, including an investigation of the effect of met allele load on memory related activation in the medial temporal lobe....... In contrast to previous studies, we found no evidence for an effect of BDNF genotype or met load during episodic memory encoding. Met allele carriers showed increased activation during successful retrieval in right hippocampus but this was contrast-specific and unaffected by met allele load. These results...
Li, Haimei; Liu, Lu; Tang, Yilang; Ji, Ning; Yang, Li; Qian, Qiujin; Wang, Yufeng
A functional polymorphism of the brain derived neurotrophic factor gene (BDNF) (Val66Met) has been suggested to be involved in the pathogenesis of attention-deficit/hyperactivity disorder (ADHD). It also has an impact on peripheral BDNF levels in psychiatric disorders. This study examined the association of Val66Met with plasma BDNF level of ADHD in Han Chinese children (170 medication - naïve ADHD patients and 155 unaffected controls, aged 6-16 years). The Val allele was showed a higher frequency in females with ADHD (n=84) than controls (P=0.029) from the case-control association study. The analysis of covariance (ANCOVA) indicated that the mean plasma BDNF levels of ADHD patients were significantly higher than that of controls (P=0.001). We performed both total sample and sex stratified analyses to investigate the effect of Val66Met genotype on the plasma BDNF levels, but only a trend of association was found in females with ADHD (n=84), with a tendency of lower plasma BDNF level in Val allele carriers than Met/Met genotype carriers (P=0.071). Our results suggested a sex-specific association between BDNF and ADHD. Furthermore, there was a possible sex-specific relationship between the BDNF Val66Met genotype and plasma BDNF levels. However, further studies are required to elucidate the role of BDNF in ADHD.
Vinberg, Maj; Trajkovska, Viktorija; Bennike, Bente
with a familiar risk of affective disorder and whether these genotypes affect whole blood BDNF level and salivary cortisol. METHOD: In a high-risk study, healthy monozygotic and dizygotic twins with and without a co-twin (high- and low-risk twins, respectively) history of affective disorder were identified...... familiar risk of affective disorder and the met allele was associated with a higher whole blood BDNF (p=0.02) and a higher evening cortisol level (p=0.01), but not with awakening cortisol. CONCLUSION: Individuals at high risk of affective disorders and who are carriers of the met allele of the Val66Met...
Lu, Weihong; Zhang, Chen; Yi, Zhenghui; Li, Zezhi; Wu, Zhiguo; Fang, Yiru
Cognitive impairment is one of the core symptoms in schizophrenia, which reflects the neurodevelopmental deficits in the etiology of this disease. Brain-derived neurotrophic factor (BDNF) plays an important role in various neurodevelopmental processes. Growing evidence has shown that BDNF may be involved in the etiology of schizophrenia. The aim of this study was to examine the association of the BDNF Val66Met polymorphism with cognition in patients with schizophrenia. Various neuropsychological tests including the Wechsler Adult Intelligence Scale-Revised, the Wechsler Memory Scale-Revised, and the Wisconsin Card Sorting Test (WCST) were employed in a sample of 112 antipsychotic-naïve patients with schizophrenia and 63 healthy controls. We examined the Val66Met polymorphism in the 112 patients and 394 controls. Among the patients, cognition was compared between Met allele carriers and non-Met allele carriers. A wide range of cognitive deficits were demonstrated in the schizophrenic patients, compared with the controls (Ps association between the Met allele and a higher percentage of perseverative errors was found in male patients (P = 0.014), but not in females (P = 0.09). Cognitive performance is broadly impaired in schizophrenic patients. The BDNF Val66Met polymorphism may be involved in the impaired executive function. This effect may have gender-specific characteristics.
Bus, B.A.A.; Arias Vasquez, A.; Franke, B.; Prickaerts, J.; Graaf, J. de; Oude Voshaar, R.C.
BACKGROUND: Association studies of the Val66Met polymorphism and serum brain-derived neurotrophic factor (BDNF) levels have yielded conflicting results. Recently, sex-specific differences in BDNF levels were demonstrated. As these might explain the reported inconsistencies, we tested sex interaction
Singh, B; Henneberger, C.; Betances, D.; Arevalo, M. A.; Rodriguez-Tebar, A.; Meier, J C; Grantyn, R.
Cultured neurons from bdnf-/- mice display reduced densities of synaptic terminals, although in vivo these deficits are small or absent. Here we aimed at clarifying the local responses to postsynaptic brain-derived neurotrophic factor (BDNF). To this end, solitary enhanced green fluorescent protein (EGFP)-labeled hippocampal neurons from bdnf-/- mice were compared with bdnf-/- neurons after transfection with BDNF, bdnf-/- neurons after transient exposure to exogenous BDNF, and bdnf+/+ neurons...
Alboni, Silvia; Tascedda, Fabio; Corsini, Daniela; Benatti, Cristina; Caggia, Federica; Capone, Giacomo; Barden, Nicholas; Blom, Joan M C; Brunello, Nicoletta
The gene coding for the neurotrophin Brain-Derived Neurotrophic Factor (BDNF) is a stress-responsive gene. Changes in its expression may underlie some of the pathological effects of stress-related disorders like depression. Data on the stress-induced regulation of the expression of BDNF in pathological conditions are rare because often research is conducted using healthy animals. In our experiments, we used transgenic mice with glucocorticoid receptor impaired (GR-i) expression in the hypothalamus created as a tool to study the neuroendocrine changes occurring in stress-related disorders. First, under basal condition, GR-i mice displayed lower levels of BDNF exons IX and IV and decreased CRE(BDNF) binding activity with respect to wild-type (WT) mice in the hippocampus. Then, we exposed GR-i and WT mice to an acute restraint stress (ARS) to test the hypothesis that GR-i mice display: 1] different ARS induced expression of BDNF, and 2] altered activation of signaling pathways implicated in regulating BDNF gene expression in the hippocampus with respect to WT mice. Results indicate that ARS enhanced BDNF mRNA expression mainly in the CA3 hippocampal sub-region of GR-i mice in the presence of enhanced levels of pro-BDNF protein, while no effect was observed in WT mice. Moreover, ARS reduced CREB signaling and binding to the BDNF promoter in GR-i mice but enhanced signaling and binding, possibly through ERK1/2 activation, in WT mice. Thus, life-long central GR dysfunction resulted in an altered sensitivity at the transcriptional level that may underlie an impaired response to an acute psycho-physical stress. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.
Taschereau-Dumouchel, Vincent; Hétu, Sébastien; Michon, Pierre-Emmanuel; Vachon-Presseau, Etienne; Massicotte, Elsa; De Beaumont, Louis; Fecteau, Shirley; Poirier, Judes; Mercier, Catherine; Chagnon, Yvon C.; Jackson, Philip L.
Motor representations in the human mirror neuron system are tuned to respond to specific observed actions. This ability is widely believed to be influenced by genetic factors, but no study has reported a genetic variant affecting this system so far. One possibility is that genetic variants might interact with visuomotor associative learning to configure the system to respond to novel observed actions. In this perspective, we conducted a candidate gene study on the Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism, a genetic variant linked to motor learning in regions of the mirror neuron system, and tested the effect of this polymorphism on motor facilitation and visuomotor associative learning. In a single-pulse TMS study carried on 16 Met (Val/Met and Met/Met) and 16 Val/Val participants selected from a large pool of healthy volunteers, Met participants showed significantly less muscle-specific corticospinal sensitivity during action observation, as well as reduced visuomotor associative learning, compared to Val homozygotes. These results are the first evidence of a genetic variant tuning sensitivity to action observation and bring to light the importance of considering the intricate relation between genetics and associative learning in order to further understand the origin and function of the human mirror neuron system. PMID:27703276
Elfving, Betina; Buttenschøn, Henriette N; Foldager, Leslie;
Brain-derived neurotrophic factor (BDNF) has been suggested as a candidate gene for depression and numerous studies have investigated the possible association between genetic variants within BDNF and depression. Clinical studies have investigated the serum BDNF levels in individuals with depression....... However, few studies have combined genetic association studies with serum BDNF measurements. The purpose of the present study was therefore to perform an investigation of BDNF using 162 individuals with depression and 289 healthy individuals. All individuals returned a completed questionnaire...... and participated in a semi-structured diagnostic interview. The major contribution of the present study is the integration of clinical assessment of cases and control individuals, simultaneous analyses of several genetic variants, serum BDNF measurements, and information on socio-demographic variables, lifestyle...
Gajewski, Patrick D; Hengstler, Jan G; Golka, Klaus; Falkenstein, Michael; Beste, Christian
In this study we examined the relevance of the functional brain-derived neurotrophic factor (BDNF) Val66Met polymorphism as a modulator of task-switching performance in healthy elderly by using behavioral and event-related potential (ERP) measures. Task switching was examined in a cue-based and a memory-based paradigm. Val/Val carriers were generally slower, showed enhanced reaction time variability and higher error rates, particularly during memory-based task switching than the Met-allele individuals. On a neurophysiological level these dissociative effects were reflected by variations in the N2 and P3 ERP components. The task switch-related N2 was increased while the P3 was decreased in Met-allele carriers, while the Val/Val genotype group revealed the opposite pattern of results. In cue-based task-switching no behavioral and ERP differences were seen between the genotypes. These data suggest that superior memory-based task-switching performance in elderly Met-allele carriers may emerge due to more efficient response selection processes. The results implicate that under special circumstances the Met-allele renders cognitive processes more efficient than the Val/Val genotype in healthy elderly, corroborating recent findings in young subjects.
Di Pino, Giovanni; Pellegrino, Giovanni; Capone, Fioravante; Assenza, Giovanni; Florio, Lucia; Falato, Emma; Lotti, Fiorenza; Di Lazzaro, Vincenzo
In search for individualized predictors of stroke recovery, the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) is attracting great interest, because it has a negative impact on neurotrophin function. Since stroke recovery relies on brain plastic processes, on which BDNF is permissive, the dominant thought is in favor of a worse recovery in Met carriers. Conversely, we suggest that Met carriers do not differ in terms of absolute ability to recover from stroke, but they do differ on the way they recover. In particular, Met carriers rely more on subcortical plasticity, while ValVal patients more on intracortical plastic processes. Indeed, the direct evidence of impaired Met carrier recovery is inconsistent, as a high worldwide diffusion of the polymorphism suggests. The plasticity taking place in cortex, which is the one targeted by noninvasive brain stimulation strategies aimed at enhancing recovery, is less pronounced in Met carrier stroke patients, who have instead spared global recovery potential. Enhanced subcortical plasticity sustains better stroke recovery of Met carrier mice: this may also happen in humans, explaining the weaker interhemispheric cortical excitability imbalance recently described in Met carriers. Thus, BDNF haplotype determines mechanisms and structures involved in stroke recovery. The less pronounced cortical plasticity of Met carrier implies that plastic changes induced by interventional neurophysiological protocols would be better predictors of ValVal chronic outcome and those protocols would be more effective to boost their recovery. Other strategies, more focused on subcortical mechanisms, should be used in Met carriers.
An application library package was developed that represents data packets for Deep Space Network (DSN) message packets as dynamically alterable arrays composed of arbitrary polymorphic data types. The software was to address a limitation of the present state of the practice for having an array directly composed of a single monomorphic data type. This is a severe limitation when one is dealing with science data in that the types of objects one is dealing with are typically not known in advance and, therefore, are dynamic in nature. The unique feature of this approach is that it enables one to define at run-time the dynamic shape of the matrix with the ability to store polymorphic data types in each of its indices. Existing languages such as C and C++ have the restriction that the shape of the array must be known in advance and each of its elements be a monomorphic data type that is strictly defined at compile-time. This program can be executed on a variety of platforms. It can be distributed in either source code or binary code form. It must be run in conjunction with any one of a number of Lisp compilers that are available commercially or as shareware.
Qin, Luye; Kim, Eunhee; Ratan, Rajiv; Lee, Francis S.; Cho, Sunghee
Brain-derived neurotrophic factor (BDNF) has been shown to be necessary and sufficient for post-stroke recovery in rodents. From these observations, we and others have hypothesized that a common single nucleotide polymorphism (SNP) in the pro-domain of bdnf that leads to a methionine (Met) substitution for valine (Val) at codon 66 (Val66Met) will affect stroke outcome. Here we investigate the effect of the BDNF genetic variant on ischemic outcome by using mice with a genetic knock-in of the h...
Full Text Available Depression is a serious and potentially life-threatening mental disorder with unknown etiology. Emerging evidence shows that brain-derived neurotrophic factor (BDNF and microRNAs (miRNAs play critical roles in the etiology of depression. Here this study was aimed to identify and characterize the roles of BDNF and its putative regulatory miRNAs in depression. First, we identified that miR-182 may be a putative miRNA that regulates BDNF levels by bioinformatic studies, and characterized the effects of miR-182 on the BDNF levels using cell-based studies, side by side with miR-132 (a known miRNA that regulates BDNF expression. We showed that treatment of miR-132 and miR-182 respectively decreased the BDNF protein levels in a human neuronal cell model, supporting the regulatory roles of miR-132 and miR-182 on the BDNF expression. Furthermore, we explored the roles of miR-132 and miR-182 on the BDNF levels in depression using human subjects by assessing their serum levels. Compared with the healthy controls, patients with depression showed lower serum BDNF levels (via the enzyme-linked immunosorbent assays and higher serum miR-132 and miR-182 levels (via the real-time PCR. Finally, the Pearson's (or Spearman's correlation coefficient was calculated to study whether there was a relationship among the Self-Rating Depression Scale score, the serum BDNF levels, and serum BDNF-related miRNA levels. Our results revealed that there was a significant negative correlation between the SDS scores and the serum BDNF levels, and a positive correlation between the SDS scores and miR-132 levels. In addition, we found a reverse relationship between the serum BDNF levels and the miR-132/miR-182 levels in depression. Collectively, we provided evidence supporting that miR-182 is a putative BDNF-regulatory miRNA, and suggested that the serum BDNF and its related miRNAs may be utilized as important biomarkers in the diagnosis or as therapeutic targets of depression.
Full Text Available Glaucoma is characterized by optic neuropathy of the RGC or retinal nerve fiber. The aim of this study was to evaluate a relationship between the neurodegenerative genes’ polymorphisms of the APOE (rs449647, BDNF (rs2030324, GRIN2B (rs3764028, and HSP70-1 (rs1043618 and the occurrence risk of POAG and to investigate its effect on allele-specific gene expression. Genomic DNA was extracted from peripheral blood. Analysis of the genes’ polymorphisms was performed using PCR-RFLP. The level of mRNA expression was determined by QRT-PCR. We showed a statistically significant association of BDNF and APOE genes’ polymorphisms with a risk of POAG occurrence. There was a statistically significant association of the rs2030324 polymorphism with progression of POAG based on cup disc ratio value and rs1043618 polymorphism based on nerve fiber index and rim area. Furthermore, we found that mean HSP70-1 mRNA expression was significantly lower in the case of individuals with the G/G genotype than in the case of minor allele carriers, that is, G/C and C/C. We also found that BDNF and HSP70-1 expression level are associated with the progression of POAG based on rim area value. In conclusion, our results suggest that BDNF, APOE, and HSP70-1 genes might be associated with a risk of POAG occurrence in the Polish population.
Nowak, Alicja; Majsterek, Ireneusz; Przybyłowska-Sygut, Karolina; Pytel, Dariusz; Szymanek, Katarzyna; Szaflik, Jerzy; Szaflik, Jacek P
Glaucoma is characterized by optic neuropathy of the RGC or retinal nerve fiber. The aim of this study was to evaluate a relationship between the neurodegenerative genes' polymorphisms of the APOE (rs449647), BDNF (rs2030324), GRIN2B (rs3764028), and HSP70-1 (rs1043618) and the occurrence risk of POAG and to investigate its effect on allele-specific gene expression. Genomic DNA was extracted from peripheral blood. Analysis of the genes' polymorphisms was performed using PCR-RFLP. The level of mRNA expression was determined by QRT-PCR. We showed a statistically significant association of BDNF and APOE genes' polymorphisms with a risk of POAG occurrence. There was a statistically significant association of the rs2030324 polymorphism with progression of POAG based on cup disc ratio value and rs1043618 polymorphism based on nerve fiber index and rim area. Furthermore, we found that mean HSP70-1 mRNA expression was significantly lower in the case of individuals with the G/G genotype than in the case of minor allele carriers, that is, G/C and C/C. We also found that BDNF and HSP70-1 expression level are associated with the progression of POAG based on rim area value. In conclusion, our results suggest that BDNF, APOE, and HSP70-1 genes might be associated with a risk of POAG occurrence in the Polish population.
Tocchetto, Andréa; Salum, Giovanni A; Blaya, Carolina; Teche, Stefania; Isolan, Luciano; Bortoluzzi, Andressa; Rebelo E Silva, Rafael; Becker, Juliana A; Bianchin, Marino M; Rohde, Luis Augusto; Leistner-Segal, Sandra; Manfro, Gisele G
Different lines of evidence support BDNF as a candidate gene in mood and anxiety modulation. More recently, the Met allele of the BDNF Val66Met polymorphism has been implicated in anxiety in animal models and anxiety-traits in humans. The aim of this study is to evaluate the a priori hypothesis that the association between anxiety disorders and Val66Met polymorphism at the BDNF gene would be replicated in a community sample of children and adolescents. 240 subjects from a total sample of 2457 children and adolescents aged 10-17 years from the public schools in the catchment area of the primary care unit of a university hospital participated in this case-control study and were assessed for psychopathology using the K-SADS-PL. A sample of saliva was collected for DNA analysis of Val66Met polymorphism. BDNF was the single gene evaluated in this sample. We found a significant association between carrying one copy of the Met allele and higher chance of anxiety disorders in children and adolescents. The association remained positive even after the adjustment for potential confounders (228 subjects; OR=3.53 (CI95% 1.77-7.06; p<0.001)). Our results support the a priori hypothesis of an association between anxiety and the polymorphism Val66Met. To our knowledge, this is the first study documenting a potential role of this polymorphism in a community sample of anxious children and adolescents.
Benzerouk, Farid; Gierski, Fabien; Gorwood, Philip; Ramoz, Nicolas; Stefaniak, Nicolas; Hübsch, Bérengère; Kaladjian, Arthur; Limosin, Frédéric
Impairment of executive functions (EFs) mediated by the prefrontal lobe is regarded as a cognitive endophenotype of alcohol dependence, being observed both in probands and in healthy offspring. Given its impact on the anatomy of the prefrontal cortex, the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism may well be involved in this specific endophenotype. Forty-six healthy adult children of alcoholics (HACA) and 82 healthy controls (HC) took part in the study. All the participants were assessed with the Diagnostic Interview for Genetic Studies, and their family histories of alcohol and substance use were assessed with the Family Informant Schedule and Criteria. The Trail Making Test, Arithmetic Switching Task, Stroop Color-Word Test and Wisconsin Card Sorting Test were administered to assess EFs. An overall executive factor score was calculated using factorial analyses. Genotyping of the BDNF Val66Met polymorphism was performed using the TaqMan® allelic discrimination assay. HACA had significantly lower EFs performance than HC. Genetic analysis showed that BDNF genotype distributions were in Hardy-Weinberg equilibrium in the HACA and HC. Genotype and allele distributions did not differ significantly between the two groups. Participants with the Met allele performed significantly more poorly than participants with the Val allele, and a group by allele interaction was observed, the BDNF Met allele being associated with a poorer executive factor score in the HACA group. These results suggest that the BDNF Val66Met polymorphism may contribute to alcohol dependence vulnerability via lower EFs performance.
Musil, Richard; Zill, Peter; Seemüller, Florian; Bondy, Brigitta; Obermeier, Michael; Spellmann, Ilja; Bender, Wolfram; Adli, Mazda; Heuser, Isabella; Zeiler, Joachim; Gaebel, Wolfgang; Maier, Wolfgang; Rietschel, Marcella; Rujescu, Dan; Schennach, Rebecca; Möller, Hans-Jürgen; Riedel, Michael
The role of the brain-derived neurotrophic factor (BDNF) in the pathophysiology of major depressive disorder (MDD) remains to be elucidated. Recent post hoc analyses indicated a potential association of three polymorphisms in the BDNF gene with worse treatment outcome in patients with the subtype of melancholic depression. We aimed at replicating these findings in a German naturalistic multicenter follow-up. Three polymorphisms in the BDNF gene (rs7103411, rs6265 (Val66Met) and rs7124442) were genotyped in 324 patients with MDD and 470 healthy controls. We applied univariate tests and logistic regression models stratifying for depression subtype and gender. The three polymorphisms were not associated with MDD as diagnosis. Further, no associations were found in univariate tests. With logistic regression, we only found a tendency towards an association of the rs6265 (Val66Met) polymorphism with overall response to treatment (response rates: GG (val/val) < GA (val/met) < AA (met/met); p = 0.0129) and some gender differences for the rs6265 (Val66Met) and rs7103411 polymorphisms. Treatment outcome stratified for subtypes of depression did not differ significantly between the investigated polymorphisms or using haplotype analyses. However, results showed a tendency towards significance. At this stage, we cannot support an influence of these three polymorphisms. Further studies in larger patient samples to increase sample sizes of subgroups are warranted.
Suchanek, Renata; Owczarek, Aleksander; Paul-Samojedny, Monika; Kowalczyk, Małgorzata; Kucia, Krzysztof; Kowalski, Jan
The brain-derived neurotrophic factor (BDNF) is one of the candidate genes for schizophrenia. There is evidence that val66met polymorphism may be involved in the pathophysiology of schizophrenia. The authors genotyped val66met (rs6265) polymorphism of the BDNF gene in 208 inpatients with paranoid schizophrenia and 254 control subjects in a Polish population. There was no association between val66met polymorphism and development of paranoid schizophrenia in either men or women. However, an association was found between this polymorphism and age at onset and psychopathology of paranoid schizophrenia. Men with the val/met genotype had an earlier age at onset, and the val/val genotype predisposed to more severe symptoms, particularly on the General Psychopathology Scale of the Positive and Negative Symptoms Scale (PANSS-G). The analysis of PANSS single items has shown that patients with the val/met genotype had higher scores on a hallucinatory behavior item than those with other genotypes.
Jamal, Mumtaz; Van der Does, Willem; Penninx, Brenda W. J. H.
Background: Smoking, especially nicotine dependence is associated with more severe symptoms of depression and anxiety disorders. However, the mechanisms underlying this association are unclear. We investigated the effect of brain-derived neurotrophic factor (BDNF) VaI(66)Met polymorphism on the seve
Alterations in brain-derived neurotrophic factor (BDNF) and its precursor proBDNF in the brain regions of a learned helplessness rat model and the antidepressant effects of a TrkB agonist and antagonist.
Shirayama, Yukihiko; Yang, Chun; Zhang, Ji-chun; Ren, Qian; Yao, Wei; Hashimoto, Kenji
Role of brain-derived neurotrophic factor (BDNF)-TrkB signaling in a learned helplessness (LH) model of depression was investigated. LH rats showed a reduction of BDNF in the medial prefrontal cortex (mPFC), CA3, and dentate gyrus (DG) of the hippocampus, whereas LH rats showed an increase in BDNF in the nucleus accumbens (NAc). Furthermore, levels of proBDNF, a BDNF precursor, were higher in the mPFC, but lower in the NAc, of LH rats. A single bilateral infusion of a TrkB agonist 7,8-DHF, but not a TrkB antagonist ANA-12, into the infralimbic (IL) of mPFC, DG, and CA3, but not the prelimbic (PrL) of mPFC, exerted antidepressant effects in LH rats. In contrast, a single bilateral infusion of ANA-12, but not 7,8-DHF, into the core and shell of NAc exerted antidepressant-like effects in LH rats, with more potent effects observed for the NAc core than for NAc shell. Interestingly, a single administration of 7,8-DHF (10mg/kg, i.p.) significantly improved a decreased phosphorylation of TrkB in the mPFC, CA3, and DG of LH rats. Additionally, ANA-12 (0.5mg/kg, i.p.) significantly improved an increased phosphorylation of TrkB in the NAc of LH rats. In conclusion, these results suggest that LH causes depression-like behavior by altering BDNF in the brain regions, and that proBDNF-BDNF processing and transport may be altered in the mPFC-NAc circuit of LH rats. Therefore, TrkB agonists might exert antidepressant effects by stimulating TrkB in the IL, CA3, and DG, while TrkB antagonists might exert antidepressant effects by blocking TrkB in the NAc.
Tsai, Shih-Jen; Hong, Chen-Jee; Yu, Younger W-Y; Chen, Tai-Jui
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.
Dincheva, Iva; Lynch, Niccola B.; Lee, Francis S.
Brain-derived neurotrophic factor (BDNF) is a growth factor that is dynamically expressed in the brain across postnatal development, regulating neuronal differentiation and synaptic plasticity. The neurotrophic hypothesis of psychiatric mood disorders postulates that in the adult brain, decreased BDNF levels leads to altered neural plasticity, contributing to disease. Although BDNF has been established as a key factor regulating the critical period plasticity in the developing visual system, it has recently been shown to also play a role in fear circuitry maturation, which has implications for the emergence of fear-related mood disorders. This review provides a detailed overview of developmental changes in expression of BDNF isoforms, as well as their receptors across postnatal life. In addition, recent developmental studies utilizing a genetic BDNF single nucleotide polymorphism (Val66Met) knock-in mouse highlight the impact of BDNF on fear learning during a sensitive period spanning the transition into adolescent time frame. We hypothesize that BDNF in the developing brain regulates fear circuit plasticity during a sensitive period in early adolescence, and alterations in BDNF expression (genetic or environmental) have a persistent impact on fear behavior and fear-related disorders. PMID:27699937
Lamb, Yvette N; Thompson, Christopher S; McKay, Nicole S; Waldie, Karen E; Kirk, Ian J
Single nucleotide polymorphisms in the brain-derived neurotrophic factor (BDNF) gene and the catechol-O-methyltransferase (COMT) gene influence brain structure and function, as well as cognitive abilities. They are most influential in the hippocampus and prefrontal cortex (PFC), respectively. Recall and recognition are forms of memory proposed to have different neural substrates, with recall having a greater dependence on the PFC and hippocampus. This study aimed to determine whether the BDNF val(66)met or COMT val(158)met polymorphisms differentially affect recall and recognition, and whether these polymorphisms interact. A sample of 100 healthy adults was assessed on recall and familiarity-based recognition using the Faces and Family Pictures subscales of the Wechsler Memory Scale - Third Edition (WMS-III). COMT genotype did not affect performance on either task. The BDNF polymorphism (i.e., met carriers relative to val homozygotes) was associated with poorer recall ability, while not influencing recognition. Combining subscale scores in memory tests such as the WMS might obscure gene effects. Our results demonstrate the importance of distinguishing between recall and familiarity-based recognition in neurogenetics research.
Yvette Nicole Lamb
Full Text Available Single nucleotide polymorphisms in the brain-derived neurotrophic factor (BDNF gene and the catechol-O-methyltransferase (COMT gene influence brain structure and function, as well as cognitive abilities. They are most influential in the hippocampus and prefrontal cortex (PFC, respectively. Recall and recognition are forms of memory proposed to have different neural substrates, with recall having a greater dependence on the PFC and hippocampus. This study aimed to determine whether the BDNF val66met or COMT val158met polymorphisms differentially affect recall and recognition, and whether these polymorphisms interact. A sample of 100 healthy adults was assessed on recall and familiarity-based recognition using the Faces and Family Pictures subscales of the Wechsler Memory Scale – Third Edition (WMS-III. COMT genotype did not affect performance on either task. The BDNF polymorphism (i.e. met carriers relative to val homozygotes was associated with poorer recall ability, while not influencing recognition. Combining subscale scores in memory tests such as the WMS might obscure gene effects. Our results demonstrate the importance of distinguishing between recall and familiarity-based recognition in neurogenetics research.
Chen, Li; Pan, Hong; Tuan, Ta Anh; Teh, Ai Ling; MacIsaac, Julia L; Mah, Sarah M; McEwen, Lisa M; Li, Yue; Chen, Helen; Broekman, Birit F P; Buschdorf, Jan Paul; Chong, Yap Seng; Kwek, Kenneth; Saw, Seang Mei; Gluckman, Peter D; Fortier, Marielle V; Rifkin-Graboi, Anne; Kobor, Michael S; Qiu, Anqi; Meaney, Michael J; Holbrook, Joanna D
Early life environments interact with genotype to determine stable phenotypic outcomes. Here we examined the influence of a variant in the brain-derived neurotropic factor (BDNF) gene (Val66Met), which underlies synaptic plasticity throughout the central nervous system, on the degree to which antenatal maternal anxiety associated with neonatal DNA methylation. We also examined the association between neonatal DNA methylation and brain substructure volume, as a function of BDNF genotype. Infant, but not maternal, BDNF genotype dramatically influences the association of antenatal anxiety on the epigenome at birth as well as that between the epigenome and neonatal brain structure. There was a greater impact of antenatal maternal anxiety on the DNA methylation of infants with the methionine (Met)/Met compared to both Met/valine (Val) and Val/Val genotypes. There were significantly more cytosine-phosphate-guanine sites where methylation levels covaried with right amygdala volume among Met/Met compared with both Met/Val and Val/Val carriers. In contrast, more cytosine-phosphate-guanine sites covaried with left hippocampus volume in Val/Val infants compared with infants of the Met/Val or Met/Met genotype. Thus, antenatal Maternal Anxiety × BDNF Val66Met Polymorphism interactions at the level of the epigenome are reflected differently in the structure of the amygdala and the hippocampus. These findings suggest that BDNF genotype regulates the sensitivity of the methylome to early environment and that differential susceptibility to specific environmental conditions may be both tissue and function specific.
Lacy, Ryan T; Brown, Russell W; Morgan, Amanda J; Mactutus, Charles F; Harrod, Steven B
In the USA, approximately 15% of women smoke tobacco cigarettes during pregnancy. In utero tobacco smoke exposure produces somatic growth deficits like intrauterine growth restriction and low birth weight in offspring, but it can also negatively influence neurodevelopmental outcomes in later stages of life, such as an increased incidence of obesity and drug abuse. Animal models demonstrate that prenatal nicotine (PN) alters the development of the mesocorticolimbic system, which is important for organizing goal-directed behavior. In the present study, we determined whether intravenous (IV) PN altered the initiation and/or expression of methamphetamine (METH)-induced locomotor sensitization as a measure of mesocorticolimbic function in adult rat offspring. We also determined whether PN and/or METH exposure altered protein levels of BDNF (brain-derived neurotrophic factor) in the nucleus accumbens, the dorsal striatum, and the prefrontal cortex of adult offspring. BDNF was of interest because of its role in the development and maintenance of the mesocorticolimbic pathway and its ability to modulate neural processes that contribute to drug abuse, such as sensitization of the dopamine system. Dams were injected with IV nicotine (0.05 mg/kg/injection) or saline, 3×/day on gestational days 8-21. Testing was conducted when offspring reached adulthood (around postnatal day 90). Following 3 once daily habituation sessions the animals received a saline injection and baseline locomotor activity was measured. PN and prenatal saline (PS)-exposed offspring then received 10 once daily injections of METH (0.3 mg/kg) to induce locomotor sensitization. The animals received a METH injection (0.3 mg/kg) to assess the expression of sensitization following a 14-day period of no injections. A day later, all animals were injected with saline and conditioned hyperactivity was assessed. Brain tissue was harvested 24 h later. PN animals habituated more slowly to the activity chambers
Cheeran, Binith; Talelli, Penelope; Mori, Francesco; Koch, Giacomo; Suppa, Antonio; Edwards, Mark; Houlden, Henry; Bhatia, Kailash; Greenwood, Richard; Rothwell, John C
The brain-derived neurotrophic factor gene (BDNF) is one of many genes thought to influence synaptic plasticity in the adult brain and shows a common single nucleotide polymorphism (BDNF Val66Met) in the normal population that is associated with differences in hippocampal volume and episodic memory. It is also thought to influence possible synaptic changes in motor cortex following a simple motor learning task. Here we extend these studies by using new non-invasive transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (TDCS) techniques that directly test the excitability and plasticity of neuronal circuits in human motor cortex in subjects at rest. We investigated whether the susceptibility to TMS probes of plasticity is significantly influenced by the BDNF polymorphism. Val66Met carriers were matched with Val66Val individuals and tested on the following protocols: continuous and intermittent theta burst TMS; median nerve paired associative stimulation; and homeostatic plasticity in the TDCS/1 Hz rTMS model. The response of Met allele carriers differed significantly in all protocols compared with the response of Val66Val individuals. We suggest that this is due to the effect of BNDF on the susceptibility of synapses to undergo LTP/LTD. The circuits tested here are implicated in the pathophysiology of movement disorders such as dystonia and are being assessed as potential new targets in the treatment of stroke. Thus the polymorphism may be one factor that influences the natural response of the brain to injury and disease.
Full Text Available Abstract Background Eating disorders (ED have a multifactorial aetiology in which genetics play an important role. Several studies have found an association between the Val66Met (G196A polymorphism of the Brain-Derived Neurotrophic Factor (BDNF and Eating disorders. The aim of this study was to determine the association of the Val66Met (G196A polymorphism of the BDNF gene and its effect on eating disorders (ED, energy intake and BMI in schoolchildren. Methods Two-year cohort study (preadolescence to adolescence. From an initial sample of 1336 Caucasian children (mean age = 11.37 years, a group at risk of ED (n = 141 and a control group (n = 117 were selected using the Children's Eating Attitudes Test. Two years later, they were re-classified into an at-risk group (n = 41 and a control group (n = 159 using the Eating Attitudes Test. The diagnosis of the individuals at risk of ED was confirmed by means of the Diagnostic Interview for Children and Adolescents. BMI, energy intake and the Val66Met (G196A polymorphism of the BDNF gene were analysed in the at-risk and control groups. Results The frequency of genotypes of the Val66Met (G196A polymorphism of the BDNF gene is 28.6% (95% CI: 22.4-34.9 in the heterozygous form (Val/Met and 5% (95% CI: 2.4-9 in the homozygous form (Met/Met. We detected no association between Val66Met genotypes and the severity of ED. Over time, the carriers of the Met66 allele with a persistent risk of ED significantly restricted energy intake (507 Kcal/day; p = 0.033. Conclusion We have not found an association between Val66Met (G196A polymorphism of the BDNF and ED in schoolchildren from general population. The relationship found between this polymorphism and energy intake restriction in adolescents with a persistent risk of ED should be replicated in a larger sample.
Réus, Gislaine Z; Dos Santos, Maria Augusta B; Abelaira, Helena M; Ribeiro, Karine F; Petronilho, Fabrícia; Vuolo, Francieli; Colpo, Gabriela D; Pfaffenseller, Bianca; Kapczinski, Flávio; Dal-Pizzol, Felipe; Quevedo, João
A growing body of evidence is pointing toward an association between immune molecules, as well brain-derived neurotrophic factor (BDNF) and the depression. The present study was aimed to evaluate the behavioral and molecular effects of the antidepressant imipramine in maternally deprived adult rats. To this aim, maternally deprived and non-deprived (control group) male rats were treated with imipramine (30mg/kg) once a day for 14 days during their adult phase. Their behavior was then assessed using the forced swimming test. In addition to this, IL-10, TNF-α and IL-1β cytokines were assessed in the serum and cerebrospinal fluid (CSF). In addition, BDNF protein levels were assessed in the prefrontal cortex, hippocampus and amygdala. In deprived rats treated with saline was observed an increase on immobility time, compared with non-deprived rats treated with imipramine (pimipramine treatment reversed the effects of maternal deprivation on BDNF and cytokines levels (pimipramine, it is suggested that classic antidepressants could exert their effects by modulating the immune system.
Rezaei, Sajjad; Asgari Mobarake, Karim; Saberi, Alia; Keshavarz, Parvaneh; Leili, Ehsan Kazemnejad
Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism is associated with functional and cognitive outcomes of stroke and plays a key role in preventing neuronal death. This study aimed to answer the following question: does BDNF Val66Met polymorphism prognosticate survival status and risk of post-stroke dementia (PSD)? In a retrospective cohort study, 206 patients with ischemic stroke (IS) entered the study. They were consecutively being admitted to the neurology clinic in Poursina Hospital (northern Iran) from 2012 to 2014. The diagnosis of PSD was based on DSM-5 criteria. The current and the premorbid cognitive statuses of the patients were respectively assessed through the third edition of Addenbrooke's Cognitive Examination and the Informant Questionnaire on Cognitive Decline in the Elderly. BDNF Val66Met gene polymorphism was determined by PCR-RFLP. On average, 48 patients (23.3 %) developed PSD 6 months after IS. Log-rank test showed that the survival rate of at least one Val-allele carriers was significantly lower than that of Met/Met homozygotes (P = 0.0005), and the former developed PSD sooner than the latter (375, 492 days, respectively). Cox model showed that heterozygous carriers of Val/Met were at greater risk of PSD over time (HR 2.280, 95 % CI 1.566-4.106, P = 0.006). However, the risk ratio of patients with PSD among different BDNF genotypes decreased after adjusting demographic, clinical, and vascular risk factors, and was no longer statistically significant (AHR 2.434, 95 % CI 0.597-9.926, P = 0.215). Val-allele carriers or Val/Met genotypes were more quickly diagnosed as having dementia after IS. However, this genetic vulnerability became more destructive when it was added to demographic, clinical, and vascular risk factors.
Lorenza S Colzato
Full Text Available Western society has an increasing proportion of older adults. Increasing age is associated with a general decrease in the control over task-relevant mental processes. In the present study we investigated the possibility that successful transfer of game-based cognitive improvements to untrained tasks in elderly people is modulated by preexisting neuro-developmental factors as genetic variability related to levels of the brain-derived neurotrophic factor (BDNF, an important neuromodulator underlying cognitive processes. We trained participants, genotyped for the BDNF Val66Met polymorphism, on cognitive tasks developed to improve dynamic attention. Pre-training (baseline and post-training measures of attentional processes (divided and selective attention were acquired by means of the Useful Field of View (UFOV task. As expected, Val/Val homozygous individuals showed larger beneficial transfer effects than Met/-carriers. Our findings support the idea that genetic predisposition modulates transfer effects.
Minelli, Alessandra; Zanardini, Roberta; Bonvicini, Cristian; Sartori, Riccardo; Pedrini, Laura; Gennarelli, Massimo; Bocchio-Chiavetto, Luisella
Consisting evidence in animal models has suggested that alterations in brain-derived neurotrophic factor (BDNF) brain expression and release are involved in the pathogenesis of mental illnesses, such as, mood, anxiety, and eating disorders. This hypothesis is supported by data emerging from biochemical studies on serum BDNF levels and genetic studies on the functional polymorphism Val66Met in the BDNF gene in patients and control subjects. Anxiety-related personality traits are associated with several mental disorders. However, they are also measurable in non-affected subjects and, so, may represent a useful "endophenotype" to study the biological correlation of the vulnerability factors in the general population. In this study, we analyzed putative correlations in subjects unaffected by mental disorders between personality traits, serum BDNF levels (N = 107), and the BDNF Val66Met genotype (N = 217). Furthermore, we tested the possible interactions between these variables. A significant correlation has been observed between high scores of harm avoidance (HA) measured by the temperament and character inventory (TCI), and low BDNF serum concentration (r = -0.253, P = 0.009). In addition, an association has been evidenced between low BDNF levels in serum and the BDNF Val/Val genotype (P = 0.021). By analyzing putative concomitant effects of different variables on HA scores in a regression model, we observed a significant correlation only with BDNF serum concentrations (P = 0.022). The study results suggest that a decrease in serum BDNF concentrations may represent a biochemical marker associated with anxiety personality traits also retrievable in the general population.
Kyzar, Evan J; Pham, Mimi; Roth, Andrew; Cachat, Jonathan; Green, Jeremy; Gaikwad, Siddharth; Kalueff, Allan V
Serotonin transporter (SERT) and brain-derived neurotrophic factor (BDNF) are key modulators of molecular signaling, cognition and behavior. Although SERT and BDNF mutant mouse phenotypes have been extensively characterized, little is known about their self-grooming behavior. Grooming represents an important behavioral domain sensitive to environmental stimuli and is increasingly used as a model for repetitive behavioral syndromes, such as autism and attention deficit/hyperactivity disorder. The present study used heterozygous ((+/-)) SERT and BDNF male mutant mice on a C57BL/6J background and assessed their spontaneous self-grooming behavior applying both manual and automated techniques. Overall, SERT(+/-) mice displayed a general increase in grooming behavior, as indicated by more grooming bouts and more transitions between specific grooming stages. SERT(+/-) mice also aborted more grooming bouts, but showed generally unaltered activity levels in the observation chamber. In contrast, BDNF(+/-) mice displayed a global reduction in grooming activity, with fewer bouts and transitions between specific grooming stages, altered grooming syntax, as well as hypolocomotion and increased turning behavior. Finally, grooming data collected by manual and automated methods (HomeCageScan) significantly correlated in our experiments, confirming the utility of automated high-throughput quantification of grooming behaviors in various genetic mouse models with increased or decreased grooming phenotypes. Taken together, these findings indicate that mouse self-grooming behavior is a reliable behavioral biomarker of genetic deficits in SERT and BDNF pathways, and can be reliably measured using automated behavior-recognition technology.
Full Text Available Cortical physiology in human motor cortex is influenced by behavioral motor training (MT as well as repetitive transcranial magnetic stimulation protocol such as intermittent theta burst stimulation (iTBS. This study aimed to test whether MT and iTBS can interact with each other to produce additive changes in motor cortical physiology. We hypothesized that potential interaction between MT and iTBS would be dependent on BDNF Val66Met polymorphism, which is known to affect neuroplasticity in the human motor cortex. Eighty two healthy volunteers were genotyped for BDNF polymorphism. Thirty subjects were assigned for MT alone, 23 for iTBS alone, and 29 for MT + iTBS paradigms. TMS indices for cortical excitability and motor map areas were measured prior to and after each paradigm. MT alone significantly increased the motor cortical excitability and expanded the motor map areas. The iTBS alone paradigm also enhanced excitability and increased the motor map areas to a slightly greater extent than MT alone. A combination of MT and iTBS resulted in the largest increases in the cortical excitability, and the representational motor map expansion of MT + iTBS was significantly greater than MT or iTBS alone only in Val/Val genotype. As a result, the additive interaction between MT and iTBS was highly dependent on BDNF Val66Met polymorphism. Our results may have clinical relevance in designing rehabilitative strategies that combine therapeutic cortical stimulation and physical exercise for patients with motor disabilities.
Eisenberg, Daniel Paul; Ianni, Angela M.; Wei, Shau-Ming; Kohn, Philip D.; Kolachana, Bhaskar; Apud, José; Weinberger, Daniel R.; Berman, Karen F.
A Val66Met single nucleotide polymorphism (SNP) in the brain-derived neurotrophic factor (BDNF) gene impairs activity-dependent BDNF release in cultured hippocampal neurons and predicts impaired memory and exaggerated basal hippocampal activity in healthy humans. Several clinical genetic association studies, along with multi-modal evidence for hippocampal dysfunction in schizophrenia indirectly suggest a relationship between schizophrenia and genetically-determined BDNF function in the hippocampus. To directly test this hypothesized relationship, we studied 47 medication-free patients with schizophrenia or schizoaffective disorder and 74 healthy comparison individuals with genotyping for the Val66Met SNP and [15O]H2O positron emission tomography (PET) to measure resting and working memory-related hippocampal regional cerebral blood flow (rCBF). In patients, harboring a Met allele was associated with significantly less hippocampal rCBF. This finding was opposite to the genotype effect seen in healthy participants, resulting in a significant diagnosis-by-genotype interaction. Exploratory analyses of interregional resting rCBF covariation revealed a specific and significant diagnosis-by-genotype interaction effect on hippocampal-prefrontal coupling. A diagnosis-by-genotype interaction was also found for working-memory related hippocampal rCBF change, which was uniquely attenuated in Met allele-carrying patients. Thus, both task-independent and task-dependent hippocampal neurophysiology accommodates a Met allelic background differently in patients with schizophrenia than in control subjects. Potentially consistent with the hypothesis that cellular sequelae of the BDNF Val66Met SNP interface with aspects of schizophrenic hippocampal and frontotemporal dysfunction, these results warrant future investigation to understand the contributions of unique patient trait or state variables to these robust interactions. PMID:23319002
Bortoluzzi, Andressa; Salum, Giovanni Abrahão; Blaya, Carolina; Silveira, Patrícia Pelufo; Grassi-Oliveira, Rodrigo; da Rosa, Eduarda Dias; de Aguiar, Bianca Wollenhaupt; Stertz, Laura; Bosa, Vera Lúcia; Schuch, Ilaine; Goldani, Marcelo; Kapczinski, Flavio; Leistner-Segal, Sandra; Manfro, Gisele Gus
The objective of this study is to investigate if a polymorphism in the NR3C2 gene moderates the association between childhood trauma on serum levels of brain derived neurothrophic factor (sBDNF). sBDNF was used here as a general marker of alteration in brain function. This is a community cross sectional study comprising 90 adolescents (54 with anxiety disorders). DNA was extracted from saliva in order to genotype the MR-2G/C (rs2070951) polymorphism using real time PCR. Blood was collected for sBDNF Elisa immunoassay. The Childhood Trauma Questionnaire (CTQ) was used to evaluate childhood abuse and neglect. Main effects and gene environment interactions were tested using linear regression models. Anxiety disorders were not associated with the MR-2G/C polymorphism or with sBDNF levels, but the number of C alleles of the MR-2G/C polymorphism was significantly associated with higher sBDNF levels (b = 8.008; p-value = 0.001). Subjects with intermediate and high exposure to physical neglect showed higher sBDNF levels if compared to subjects non-exposed (b = 11.955; p = 0.004 and b = 16.186; p = 0.009, respectively). In addition, we detected a significant physical neglect by MR-2G/C C allele interaction on sBDNF levels (p = 0.005), meaning that intermediate and high exposure to childhood neglect were only associated with increased sBDNF levels in subjects with the CC genotype, but not in subjects with other genotypes. Our findings suggest that genetic variants in NR3C2 gene may partially explain plastic brain vulnerability to traumatic events. Further studies are needed to investigate the moderating effects of NR3C2 gene in more specific markers of alteration in brain function.
Severe developmental thyroid hormone (TH) insufficiency results in alterations in brain structure/function and lasting behavioral impairments. Environmental toxicants reduce circulating levels of TH, but the disruption is modest and the doseresponse relationships of TH and neuro...
Chen, Jie; Li, Xinying; McGue, Matt
Background: Confounding introduced by gene-environment correlation (rGE) may prevent one from observing a true gene-environment interaction (G × E) effect on psychopathology. The present study investigated the interacting effect of the BDNF Val66Met polymorphism and stressful life events (SLEs) on adolescent depression while controlling for the…
Yeh, Ting-Kuang; Hu, Chung-Yi; Yeh, Ting-Chi; Lin, Pei-Jung; Wu, Chung-Hsin; Lee, Po-Lei; Chang, Chun-Yen
The contribution of genetic factors to the memory is widely acknowledged. Research suggests that these factors include genes involved in the dopaminergic pathway, as well as the genes for brain-derived neurotrophic factor (BDNF) and methylenetetrahydrofolate reductase (MTHFR). The activity of the products of these genes is affected by single…
Estimation of BDNF gene polymorphism and predisposition to dependence development for selected psychoactive compounds: genetic aspects of addiction with the selected drugs, amphetamine, tetrahydrocannabinol and opiates.
Biskupska, J; Borowiak, K S; Karlin-Grazewicz, K; Janus, T; Waloszczyk, P; Potocka-Banas, B; Machoy-Mokrzynska, A; Ossowski, A; Ciechanowicz, A
The etiology of drug addiction, a central nervous system (CNS) disease, is not fully known. This complex problem is believed to be connected with concurrently affecting genetic, psychological and environmental factors. The development of addiction is connected with CNS reinforcement system and dopaminergic neurotransmission. Molecular processes are postulated to be of universal character and allow to presume a similar mechanism of dependence for both ethanol and other substances. Therefore, elements of dopaminergic transmission become excellent candidates for the examination of genetic influence on the development of addiction. A relationship between alcoholic disease and the presence of TaqIA1 and DRD2 alleles permits to initiate another investigation of gene-coding DRD2 dopamine receptor. The latest results indicate the importance of brain-derived neurotrophic factor (BDNF) in the regulation of dopaminergic route. The purpose of this research was to reveal the relationship between the Val66Met BDNF gene polymorphism and dependence of psychoactive agent. The examinations were performed with the Local Research Ethics Committee approval and patient's consent. The study group consisted of 100 patients (88 men and 12 women) aged 18-52 years, qualified for research program according to the International Classification of Diseases, Tenth Revision (ICD-10) requirements, medical examination and detailed questionnaire.
Full Text Available Brain derived neurotrophic factor (BDNF plays key roles in several neurodevelopmental disorders and actions of pharmacological treatments. However it is uncealr how specific BDNF’s effects are on diffeerent circuit components. Current studies have largely focused on the role of BDNF in modification of synaptic development. The precise roles of BDNF in the refinement of a functional circuit in vivo remain unclear. Val66Met polymorphism of BDNF may be associated with increased risk for cognitive impairments and is mediated at least in part by activity-dependent trafficking and/or secretion of BDNF. Using mutant mice that lacked activity-driven BDNF expression (bdnf-KIV, we previously reported that experience regulation of the cortical GABAergic network is mediated by activity-driven BDNF expression. Here, we demonstrate that activity-driven BDNF’s effects on circuits formed by the layer IV spiny stellate cells are highly specific. Structurally, dendritic but not axonal morphology was altered in the mutant. Physiologically, GABAergic but not glutamatergic synapses were severely affected. The effects on GABA transmission occurs via presynaptic alteration of calcium-dependent release probability. These results suggest that neuronal activity through activity-driven BDNF expression, can selectively regulate specific features of layer IV circuits in vivo. We postulate that the role of activity-dependent BDNF is to modulate the computational ability of circuits that relate to the gain control (i.e. feed-forward inhibition; whereas the basic wiring of circuits relevant to the sensory pathway is spared. Gain control modulation within cortical circuits has broad impact on cognitive processing and brain state-transitions. Cognitive behavior and mode is determined by brain states, thus the studying of circuit alteration by endogenous BDNF provides insights into the cellular and molecular mechanisms of diseases mediated by BDNF.
Development of a cost-efficient novel method for rapid, concurrent genotyping of five common single nucleotide polymorphisms of the brain derived neurotrophic factor (BDNF) gene by tetra-primer amplification refractory mutation system.
Wang, Cathy K; Xu, Michael S; Ross, Colin J; Lo, Ryan; Procyshyn, Ric M; Vila-Rodriguez, Fidel; White, Randall F; Honer, William G; Barr, Alasdair M
Brain derived neurotrophic factor (BDNF) is a molecular trophic factor that plays a key role in neuronal survival and plasticity. Single nucleotide polymorphisms (SNPs) of the BDNF gene have been associated with specific phenotypic traits in a large number of neuropsychiatric disorders and the response to psychotherapeutic medications in patient populations. Nevertheless, due to study differences and occasionally contrasting findings, substantial further research is required to understand in better detail the association between specific BDNF SNPs and these psychiatric disorders. While considerable progress has been made recently in developing advanced genotyping platforms of SNPs, many high-throughput probe- or array-based detection methods currently available are limited by high costs, slow processing times or access to advanced instrumentation. The polymerase chain reaction (PCR)-based, tetra-primer amplification refractory mutation system (T-ARMS) method is a potential alternative technique for detecting SNP genotypes efficiently, quickly, easily, and cheaply. As a tool in psychopathology research, T-ARMS was shown to be capable of detecting five common SNPs in the BDNF gene (rs6265, rs988748, rs11030104, 11757G/C and rs7103411), which are all SNPs with previously demonstrated clinical relevance to schizophrenia and depression. The present technique therefore represents a suitable protocol for many research laboratories to study the genetic correlates of BDNF in psychiatric disorders. Copyright Copyright © 2015 John Wiley & Sons, Ltd.
Burns, Brooke; Schmidt, Kristie; Williams, Stephen R; Kim, Sun; Girirajan, Santhosh; Elsea, Sarah H
Smith-Magenis syndrome (SMS) is a genetic disorder caused by haploinsufficiency of the retinoic acid induced 1 (RAI1) gene. In addition to intellectual disabilities, behavioral abnormalities and sleep disturbances, a majority of children with SMS also have significant early-onset obesity. To study the role of RAI1 in obesity, we investigated the growth and obesity phenotype in a mouse model haploinsufficient for Rai1. Data show that Rai1(+/-) mice are hyperphagic, have an impaired satiety response and have altered abdominal and subcutaneous fat distribution, with Rai1(+/-) female mice having a higher proportion of abdominal fat when compared with wild-type female mice. Expression analyses revealed that Bdnf (brain-derived neurotrophic factor), a gene previously associated with hyperphagia and obesity, is downregulated in the Rai1(+/-) mouse hypothalamus, and reporter studies show that RAI1 directly regulates the expression of BDNF. Even though the Rai1(+/-) mice are significantly obese, serum analyses do not reveal any evidence of metabolic syndrome. Supporting these findings, a caregiver survey revealed that even though a high incidence of abdominal obesity is observed in females with SMS, they did not exhibit a higher incidence of indicators of metabolic syndrome above the general population. We conclude that Rai1 haploinsufficiency represents a single-gene model of obesity with hyperphagia, abnormal fat distribution and altered hypothalamic gene expression associated with satiety, food intake, behavior and obesity. Linking RAI1 and BDNF provides a more thorough understanding of the role of Rai1 in growth and obesity and insight into the complex pathogenicity of obesity, behavior and sex-specific differences in adiposity.
Full Text Available Objective:To investigate the effects of ethanol exposure in adolescent rats during adulthood by assesssing aggression and anxiety-like behaviors and measuring the levels of inflammatory markers.Methods:Groups of male Wistar rats (mean weight 81.4 g, n = 36 were housed in groups of four until postnatal day (PND 60. From PNDs 30 to 46, rats received one of three treatments: 3 g/kg of ethanol (15% w/v, orally, n = 16, 1.5 g/kg of ethanol (12.5% w/v, PO, n = 12, or water (n = 12 every 48 hours. Animals were assessed for aggressive behavior (resident x intruder test and anxiety-like behaviors (elevated plus maze during adulthood.Results:Animals that received low doses of alcohol showed reduced levels of brain-derived neurotrophic factor (BDNF in the hippocampus as compared to the control group. No significant difference was found in prefrontal cortex.Conclusions:Intermittent exposure to alcohol during adolescence is associated with lower levels of BDNF in the hippocampus, probably due the episodic administration of alcohol, but alcohol use did not alter the level agression toward a male intruder or anxiety-like behaviors during the adult phase.
Fisher, Patrick M; Holst, Klaus K; Adamsen, Dea;
) polymorphism. We applied a linear latent variable model (LVM) using regional 5-HT4 binding values (neocortex, amygdala, caudate, hippocampus, and putamen) from 68 healthy humans, allowing us to explicitly model brain-wide and region-specific genotype effects on 5-HT4 binding. Our data supported an LVM wherein...
Gadow, Kenneth D.; Roohi, Jasmin; Devincent, Carla J.; Kirsch, Sarah; Hatchwell, Eli
The aim of the study is to examine rs4680 ("COMT") and rs6265 ("BDNF") as genetic markers of anxiety, ADHD, and tics. Parents and teachers completed a DSM-IV-referenced rating scale for a total sample of 67 children with autism spectrum disorder (ASD). Both "COMT" (p = 0.06) and "BDNF" (p = 0.07) genotypes were marginally significant for teacher…
admission and remained impaired in most domains across the timepoints, although delayed signs of recovery were noted to be significant in the domains attention and overall cognition. In conclusion, the current study has demonstrated the role of the BDNF rs6265 Val66Met polymorphism in influencing specific neurocognitive outcomes in patients with mTBI. Findings were more detrimentally profound among Met allele carriers.
Du, Xiaoyan; Cui, Jing; Wang, Chao; Huo, Xueyun; Lu, Jing; Li, Yichen; Chen, Zhenwen
Microsatellites are 50-200 repetitive DNA sequences composed of 1- to 6-base-pair-long reiterative motifs within the genome. They are vulnerable to DNA modifications, such as recombination and/or integration, and are recognized as "sentinel" DNA. Our previous report indicated that the genotypes of the microsatellite loci could change from mono- to poly-morphisms (CMP) in gene knockout (KO) mice, implying that genetic modification induces microsatellite mutation. However, it is still unclear whether the random insertion of DNA fragments into mice genomes produced via transgene (Tg) or N-ethyl-N-nitrosourea (ENU) would also result in microsatellite mutations or microsatellite loci genotypes changes. This study was designed to find possible clues to answer this question. In brief, 198 microsatellite loci that were distributed among almost all of the chromosomes (except for the Y) were examined through polymerase chain reaction to screen possible CMPs in six Tg strains. First, for each strain, the microsatellite sequences of all loci were compared between Tg and the corresponding background strain to exclude genetic interference. Simultaneously, to exclude spontaneous mutation-related CMPs that might exist in the examined six strains, mice from five spontaneously mutated inbred strains were used as the negative controls. Additionally, the sequences of all loci in these spontaneous mutated mice were compared to corresponding genetic background controls. The results showed that 40 of the 198 (20.2%) loci were identified as having CMPs in the examined Tg mice strains. The CMP genotypes were either homozygous or heterozygous compared to the background controls. Next, we applied the 40 CMP positive loci in ENU-mutated mice and their corresponding background controls. After that, a general comparison of CMPs that exist among Tg, ENU-treated and KO mouse strains was performed. The results indicated that four (D11mit258, D13mit3, D14mit102 and DXmit172) of the 40 (10%) CMP
Full Text Available OBJECTIVE: To examine the maturational changes in proteomic polymorphisms resulting from differential expression by multiple intrinsic fungi in the caterpillar body and stroma of natural Cordyceps sinensis (Cs, an integrated micro-ecosystem. METHODS: The surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS biochip technique was used to profile the altered protein compositions in the caterpillar body and stroma of Cs during its maturation. The MS chromatograms were analyzed using density-weighted algorithms to examine the similarities and cluster relationships among the proteomic polymorphisms of the Cs compartments and the mycelial products Hirsutella sinensis (Hs and Paecilomyces hepiali (Ph. RESULTS: SELDI-TOF MS chromatograms displayed dynamic proteomic polymorphism alterations among samples from the different Cs compartments during maturation. More than 1,900 protein bands were analyzed using density-weighted ZUNIX similarity equations and clustering methods, revealing integral polymorphism similarities of 57.4% between the premature and mature stromata and 42.8% between the premature and mature caterpillar bodies. The across-compartment similarity was low, ranging from 10.0% to 18.4%. Consequently, each Cs compartment (i.e., the stroma and caterpillar body formed a clustering clade, and the 2 clades formed a Cs cluster. The polymorphic similarities ranged from 0.51% to 1.04% between Hs and the Cs compartments and were 2.8- to 4.8-fold higher (1.92%-4.34% between Ph and the Cs compartments. The Hs and Ph mycelial samples formed isolated clades outside of the Cs cluster. CONCLUSION: Proteomic polymorphisms in the caterpillar body and stroma of Cs change dynamically during maturation. The proteomic polymorphisms in Hs and Ph differ from those in Cs, suggesting the presence of multiple Cs-associated fungi and multiple Ophiocordyceps sinensis genotypes with altered differential protein expression in the Cs
Wu, Zi-Mei; Gao, Ling; Yao, Yi-Sang; Tan, Ning-Zhi; Wu, Jian-Yong; Ni, Luqun; Zhu, Jia-Shi
Objective To examine the maturational changes in proteomic polymorphisms resulting from differential expression by multiple intrinsic fungi in the caterpillar body and stroma of natural Cordyceps sinensis (Cs), an integrated micro-ecosystem. Methods The surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) biochip technique was used to profile the altered protein compositions in the caterpillar body and stroma of Cs during its maturation. The MS chromatograms were analyzed using density-weighted algorithms to examine the similarities and cluster relationships among the proteomic polymorphisms of the Cs compartments and the mycelial products Hirsutella sinensis (Hs) and Paecilomyces hepiali (Ph). Results: SELDI-TOF MS chromatograms displayed dynamic proteomic polymorphism alterations among samples from the different Cs compartments during maturation. More than 1,900 protein bands were analyzed using density-weighted ZUNIX similarity equations and clustering methods, revealing integral polymorphism similarities of 57.4% between the premature and mature stromata and 42.8% between the premature and mature caterpillar bodies. The across-compartment similarity was low, ranging from 10.0% to 18.4%. Consequently, each Cs compartment (i.e., the stroma and caterpillar body) formed a clustering clade, and the 2 clades formed a Cs cluster. The polymorphic similarities ranged from 0.51% to 1.04% between Hs and the Cs compartments and were 2.8- to 4.8-fold higher (1.92%–4.34%) between Ph and the Cs compartments. The Hs and Ph mycelial samples formed isolated clades outside of the Cs cluster. Conclusion Proteomic polymorphisms in the caterpillar body and stroma of Cs change dynamically during maturation. The proteomic polymorphisms in Hs and Ph differ from those in Cs, suggesting the presence of multiple Cs-associated fungi and multiple Ophiocordyceps sinensis genotypes with altered differential protein expression in the Cs compartments
Costa, Valerio; Federico, Antonio; Pollastro, Carla; Ziviello, Carmela; Cataldi, Simona; Formisano, Pietro; Ciccodicola, Alfredo
Type 2 diabetes (T2D) is one of the most frequent mortality causes in western countries, with rapidly increasing prevalence. Anti-diabetic drugs are the first therapeutic approach, although many patients develop drug resistance. Most drug responsiveness variability can be explained by genetic causes. Inter-individual variability is principally due to single nucleotide polymorphisms, and differential drug responsiveness has been correlated to alteration in genes involved in drug metabolism (CYP2C9) or insulin signaling (IRS1, ABCC8, KCNJ11 and PPARG). However, most genome-wide association studies did not provide clues about the contribution of DNA variations to impaired drug responsiveness. Thus, characterizing T2D drug responsiveness variants is needed to guide clinicians toward tailored therapeutic approaches. Here, we extensively investigated polymorphisms associated with altered drug response in T2D, predicting their effects in silico. Combining different computational approaches, we focused on the expression pattern of genes correlated to drug resistance and inferred evolutionary conservation of polymorphic residues, computationally predicting the biochemical properties of polymorphic proteins. Using RNA-Sequencing followed by targeted validation, we identified and experimentally confirmed that two nucleotide variations in the CAPN10 gene—currently annotated as intronic—fall within two new transcripts in this locus. Additionally, we found that a Single Nucleotide Polymorphism (SNP), currently reported as intergenic, maps to the intron of a new transcript, harboring CAPN10 and GPR35 genes, which undergoes non-sense mediated decay. Finally, we analyzed variants that fall into non-coding regulatory regions of yet underestimated functional significance, predicting that some of them can potentially affect gene expression and/or post-transcriptional regulation of mRNAs affecting the splicing. PMID:27347941
Full Text Available Type 2 diabetes (T2D is one of the most frequent mortality causes in western countries, with rapidly increasing prevalence. Anti-diabetic drugs are the first therapeutic approach, although many patients develop drug resistance. Most drug responsiveness variability can be explained by genetic causes. Inter-individual variability is principally due to single nucleotide polymorphisms, and differential drug responsiveness has been correlated to alteration in genes involved in drug metabolism (CYP2C9 or insulin signaling (IRS1, ABCC8, KCNJ11 and PPARG. However, most genome-wide association studies did not provide clues about the contribution of DNA variations to impaired drug responsiveness. Thus, characterizing T2D drug responsiveness variants is needed to guide clinicians toward tailored therapeutic approaches. Here, we extensively investigated polymorphisms associated with altered drug response in T2D, predicting their effects in silico. Combining different computational approaches, we focused on the expression pattern of genes correlated to drug resistance and inferred evolutionary conservation of polymorphic residues, computationally predicting the biochemical properties of polymorphic proteins. Using RNA-Sequencing followed by targeted validation, we identified and experimentally confirmed that two nucleotide variations in the CAPN10 gene—currently annotated as intronic—fall within two new transcripts in this locus. Additionally, we found that a Single Nucleotide Polymorphism (SNP, currently reported as intergenic, maps to the intron of a new transcript, harboring CAPN10 and GPR35 genes, which undergoes non-sense mediated decay. Finally, we analyzed variants that fall into non-coding regulatory regions of yet underestimated functional significance, predicting that some of them can potentially affect gene expression and/or post-transcriptional regulation of mRNAs affecting the splicing.
Bilbo, Staci D; Barrientos, Ruth M; Eads, Andrea S; Northcutt, Alexis; Watkins, Linda R; Rudy, Jerry W; Maier, Steven F
Neonatal bacterial infection in rats leads to profound hippocampal-dependent memory impairments following a peripheral immune challenge in adulthood. Here, we determined whether neonatal infection plus an immune challenge in adult rats is associated with impaired induction of brain-derived neurotrophic factor (BDNF) within the hippocampus (CA1, CA3, and dentate gyrus) following fear conditioning. BDNF is well characterized for its critical role in learning and memory. Rats injected on postnatal day 4 with PBS (vehicle) or Escherichia coli received as adults either no conditioning or a single 2min trial of fear conditioning. Half of the rats in the conditioned group then received a peripheral injection of 25mug/kg lipopolysaccharide (LPS) and all were sacrificed 1 or 4h later. Basal (unconditioned) BDNF mRNA did not differ between groups. However, following conditioning, neonatal infection with E. coli led to decreased BDNF mRNA induction in all regions compared to PBS-treated rats. This decrease in E. coli-treated rats was accompanied by a large increase in IL-1beta mRNA in CA1. Taken together, these data indicate that early infection strongly influences the induction of IL-1beta and BDNF within distinct regions of the hippocampus, which likely contribute to observed memory impairments in adulthood.
Krabbe, K. S.; Nielsen, A. R.; Krogh-Madsen, R.;
Aims/hypothesis Decreased levels of brain-derived neurotrophic factor (BDNF) have been implicated in the pathogenesis of Alzheimer's disease and depression. These disorders are associated with type 2 diabetes, and animal models suggest that BDNF plays a role in insulin resistance. We therefore...... explored whether BDNF plays a role in human glucose metabolism. Subjects and methods We included (Study 1) 233 humans divided into four groups depending on presence or absence of type 2 diabetes and presence or absence of obesity; and (Study 2) seven healthy volunteers who underwent both a hyperglycaemic...... and a hyperinsulinaemic-euglycaemic clamp. Results Plasma levels of BDNF in Study 1 were decreased in humans with type 2 diabetes independently of obesity. Plasma BDNF was inversely associated with fasting plasma glucose, but not with insulin. No association was found between the BDNF G196A (Val66Met) polymorphism...
Chikahisa, Sachiko; Sei, Hiroyoshi; Morishima, Masaki; Sano, Atsuko; Kitaoka, Kazuyoshi; Nakaya, Yutaka; Morita, Yusuke
Music has been suggested to have a beneficial effect on various types of performance in humans. However, the physiological and molecular mechanism of this effect remains unclear. We examined the effect of music exposure during the perinatal period on learning behavior in adult mice, and measured the levels of brain-derived neurotrophic factor (BDNF) and its receptor, tyrosine kinase receptor B (TrkB), which play critical roles in synaptic plasticity. In addition, we measured the levels of 3-phosphoinositide-dependent protein kinase-1 (PDK1) and mitogen-activated protein kinase (MAPK), downstream targets of two main pathways in BDNF/TrkB signaling. Music-exposed mice completed a maze learning task with fewer errors than the white noise-exposed mice and had lower levels of BDNF and higher levels of TrkB and PDK1 in the cortex. MAPK levels were unchanged. Furthermore, TrkB and PDK1 protein levels in the cortex showed a significant negative correlation with the number of errors on the maze. These results suggest that perinatal exposure of mice to music has an influence on BDNF/TrkB signaling and its intracellular signaling pathway targets, including PDK1, and thus may induce improved learning and memory functions.
Griesbach, Grace Sophia; Hovda, David Allen; Molteni, Raffaella; Gomez-Pinilla, Fernando
Brain-derived neurotrophic factor (BDNF), its signal transduction receptor trkB, and its downstream effector, synapsin I, were measured in the hippocampus and occipital cortex of young animals after fluid-percussion brain injury (FPI). Isofluorane anaesthetized postnatal day 19 rats were subjected to a mild lateral FPI or sham injury. Rats were sacrificed at 24 h, 7 days, or 14 days after injury in order to determine mRNA expression. Additional animals were sacrificed at 7 and 14 days after injury for protein analysis. Only FPI animals exhibited hemispheric differences in BDNF levels. These animals exhibited a contralateral increase, ranging from 40% to 75%, in BDNF mRNA within both the hippocampus and occipital cortex at 24 h and 7 days after injury. The increase in message within the occipital cortex was accompanied by an increase in BDNF protein at 7 and 14 days after injury. However, hippocampal BDNF protein increased in both hemispheres at postinjury day 7 and was restricted to the ipsilateral hippocampus at postinjury day 14. At postinjury day 7, both trkB and synapsin I mRNA expression increased ipsilaterally and decreased contralaterally in the occipital cortex. In addition, synapsin I phosphorylation was increased by 20% in the ipsilateral cortex and by 30% in the hippocampus on this day. These results indicate that the developing brain responds to a mild injury by modifying factors related to synaptic plasticity and suggest that regions remote from the site of injury express neurotrophic signals potentially needed for compensatory responses.
Lampe, Johanna W; Peterson, Sabrina
The chemoprotective effect of cruciferous vegetables is due to their high glucosinolate content and the capacity of glucosinolate metabolites, such as isothiocyanates (ITC) and indoles, to modulate biotransformation enzyme systems (e.g., cytochromes P450 and conjugating enzymes). Data from molecular epidemiologic studies suggest that genetic and associated functional variations in biotransformation enzymes, particularly glutathione S-transferase (GST)M1 and GSTT1, which metabolize ITC, alter cancer risk in response to cruciferous vegetable exposure. Moreover, genetic polymorphisms in receptors and transcription factors that interact with these compounds may further contribute to variation in response to cruciferous vegetable intake. This review outlines the metabolism and mechanisms of action of cruciferous vegetable constituents, discusses the recent human studies testing effects of cruciferous vegetables on biotransformation systems and summarizes the epidemiologic and experimental evidence for an effect of genetic polymorphisms in these enzymes on response to cruciferous vegetable intake. Taken together, genetic differences in biotransformation enzymes and the factors that regulate them, as well as variation in glucosinolate content of cruciferous vegetables and the methods used to prepare these foods underscore the multiple layers of complexity that affect the study of gene-diet interactions and cancer risk in humans.
Cunha, Carla; Brambilla, Riccardo; Thomas, Kerrie L
Since its discovery almost three decades ago, the secreted neurotrophin brain-derived neurotrophic factor (BDNF) has been firmly implicated in the differentiation and survival of neurons of the CNS. More recently, BDNF has also emerged as an important regulator of synaptogenesis and synaptic plasticity mechanisms underlying learning and memory in the adult CNS. In this review we will discuss our knowledge about the multiple intracellular signalling pathways activated by BDNF, and the role of this neurotrophin in long-term synaptic plasticity and memory formation as well as in synaptogenesis. We will show that maturation of BDNF, its cellular localization and its ability to regulate both excitatory and inhibitory synapses in the CNS may result in conflicting alterations in synaptic plasticity and memory formation. Lack of a precise knowledge about the mechanisms by which BDNF influences higher cognitive functions and complex behaviours may constitute a severe limitation in the possibility to devise BDNF-based therapeutics for human disorders of the CNS.
Rachel D Penrod
Full Text Available Medium spiny neurons (MSNs are the major striatal neuron and receive synaptic input from both glutamatergic and dopaminergic afferents. These synapses are made on MSN dendritic spines, which undergo density and morphology changes in association with numerous disease and experience-dependent states. Despite wide interest in the structure and function of mature MSNs, relatively little is known about MSN development. Furthermore, most in vitro studies of MSN development have been done in simple striatal cultures that lack any type of non-autologous synaptic input, leaving open the question of how MSN development is affected by a complex environment that includes other types of neurons, glia, and accompanying secreted and cell-associated cues. Here we characterize the development of MSNs in striatal-cortical co-culture, including quantitative morphological analysis of dendritic arborization and spine development, describing progressive changes in density and morphology of developing spines. Overall, MSN growth is much more robust in the striatal-cortical co-culture compared to striatal mono-culture. Inclusion of dopamine in the co-culture further enhances MSN dendritic arborization and spine density, but the effects of dopamine on dendritic branching are only significant at later times in development. In contrast, exogenous Brain Derived Neurotrophic Factor (BDNF has only a minimal effect on MSN development in the co-culture, but significantly enhances MSN dendritic arborization in striatal mono-culture. Importantly, inhibition of NMDA receptors in the co-culture significantly enhances the effect of exogenous BDNF, suggesting that the efficacy of BDNF depends on the cellular environment. Combined, these studies identify specific periods of MSN development that may be particularly sensitive to perturbation by external factors and demonstrate the importance of studying MSN development in a complex signaling environment.
Zoladz, Phillip R; Dailey, Alison M; Nagle, Hannah E; Fiely, Miranda K; Mosley, Brianne E; Brown, Callie M; Duffy, Tessa J; Scharf, Amanda R; Earley, McKenna B; Rorabaugh, Boyd R
FK506 binding protein 51 (FKBP5) is a co-chaperone of heat shock protein 90 and significantly influences glucocorticoid receptor sensitivity. Single nucleotide polymorphisms (SNPs) in the FKBP5 gene are associated with altered hypothalamus-pituitary-adrenal (HPA) axis function, changes in the structure and function of several cognitive brain areas, and increased susceptibility to post-traumatic stress disorder, major depression, bipolar disorder and suicidal events. The mechanisms underlying these associations are largely unknown, but it has been speculated that the influence of these SNPs on emotional memory systems may play a role. In the present study, 112 participants were exposed to the socially evaluated cold pressor test (stress) or control (no stress) conditions immediately prior to learning a list of 42 words. Participant memory was assessed immediately after learning (free recall) and 24 h later (free recall and recognition). Participants provided a saliva sample that enabled the genotyping of three FKBP5 polymorphisms: rs1360780, rs3800373 and rs9296158. Results showed that stress impaired immediate recall in risk allele carriers. More importantly, stress enhanced long-term recall and recognition memory in non-carriers of the risk alleles, effects that were completely absent in risk allele carriers. Follow-up analyses revealed that memory performance was correlated with salivary cortisol levels in non-carriers, but not in carriers. These findings suggest that FKBP5 risk allele carriers may possess a sensitized stress response system, perhaps specifically for stress-induced changes in corticosteroid levels, which might aid our understanding of how SNPs in the FKBP5 gene confer increased risk for stress-related psychological disorders and their related phenotypes.
Davis, Margaret I
Brain-derived neurotrophic factor (BDNF) has emerged as a regulator of development, plasticity and, recently, addiction. Decreased neurotrophic activity may be involved in ethanol-induced neurodegeneration in the adult brain and in the etiology of alcohol-related neurodevelopmental disorders. This can occur through decreased expression of BDNF or through inability of the receptor to transduce signals in the presence of ethanol. In contrast, recent studies implicate region-specific up-regulation of BDNF and associated signaling pathways in anxiety, addiction and homeostasis after ethanol exposure. Anxiety and depression are precipitating factors for substance abuse and these disorders also involve region-specific changes in BDNF in both pathogenesis and response to pharmacotherapy. Polymorphisms in the genes coding for BDNF and its receptor TrkB are linked to affective, substance abuse and appetitive disorders and therefore may play a role in the development of alcoholism. This review summarizes historical and pre-clinical data on BDNF and TrkB as it relates to ethanol toxicity and addiction. Many unresolved questions about region-specific changes in BDNF expression and the precise role of BDNF in neuropsychiatric disorders and addiction remain to be elucidated. Resolution of these questions will require significant integration of the literature on addiction and comorbid psychiatric disorders that contribute to the development of alcoholism.
Full Text Available Abstract Background Brain-derived neurotrophic factor (BDNF is a small secreted protein that has important roles in the developing and adult nervous system. Altered expression or changes in the regulation of the BDNF gene have been implicated in a variety of human nervous system disorders. Although regulation of the rodent BDNF gene has been extensively investigated, in vivo studies regarding the human BDNF gene are largely limited to postmortem analysis. Bacterial artificial chromosome (BAC transgenic mice harboring the human BDNF gene and its regulatory flanking sequences constitute a useful tool for studying human BDNF gene regulation and for identification of therapeutic compounds modulating BDNF expression. Results In this study we have generated and analyzed BAC transgenic mice carrying 168 kb of the human BDNF locus modified such that BDNF coding sequence was replaced with the sequence of a fusion protein consisting of N-terminal BDNF and the enhanced green fluorescent protein (EGFP. The human BDNF-BAC construct containing all BDNF 5' exons preceded by different promoters recapitulated the expression of endogenous BDNF mRNA in the brain and several non-neural tissues of transgenic mice. All different 5' exon-specific BDNF-EGFP alternative transcripts were expressed from the transgenic human BDNF-BAC construct, resembling the expression of endogenous BDNF. Furthermore, BDNF-EGFP mRNA was induced upon treatment with kainic acid in a promotor-specific manner, similarly to that of the endogenous mouse BDNF mRNA. Conclusion Genomic region covering 67 kb of human BDNF gene, 84 kb of upstream and 17 kb of downstream sequences is sufficient to drive tissue-specific and kainic acid-induced expression of the reporter gene in transgenic mice. The pattern of expression of the transgene is highly similar to BDNF gene expression in mouse and human. This is the first study to show that human BDNF gene is regulated by neural activity.
Full Text Available Abstract Background Proneurotrophins and mature neurotrophins elicit opposite effects via the p75 neurotrophin receptor (p75NTR and Trk tyrosine kinase receptors, respectively; however the molecular roles of proneurotrophins in the CNS are not fully understood. Results Based on two rare single nucleotide polymorphisms (SNPs of the human brain-derived neurotrophic factor (BDNF gene, we generated R125M-, R127L- and R125M/R127L-BDNF, which have amino acid substitution(s near the cleavage site between the pro- and mature-domain of BDNF. Western blot analyses demonstrated that these BDNF variants are poorly cleaved and result in the predominant secretion of proBDNF. Using these cleavage-resistant proBDNF (CR-proBDNF variants, the molecular and cellular roles of proBDNF on the CNS neurons were examined. First, CR-proBDNF showed normal intracellular distribution and secretion in cultured hippocampal neurons, suggesting that inhibition of proBDNF cleavage does not affect intracellular transportation and secretion of BDNF. Second, we purified recombinant CR-proBDNF and tested its biological effects using cultured CNS neurons. Treatment with CR-proBDNF elicited apoptosis of cultured cerebellar granule neurons (CGNs, while treatment with mature BDNF (matBDNF promoted cell survival. Third, we examined the effects of CR-proBDNF on neuronal morphology using more than 2-week cultures of basal forebrain cholinergic neurons (BFCNs and hippocampal neurons. Interestingly, in marked contrast to the action of matBDNF, which increased the number of cholinergic fibers and hippocampal dendritic spines, CR-proBDNF dramatically reduced the number of cholinergic fibers and hippocampal dendritic spines, without affecting the survival of these neurons. Conclusion These results suggest that proBDNF has distinct functions in different populations of CNS neurons and might be responsible for specific physiological cellular processes in the brain.
Yamamori, Hidenaga; Hashimoto, Ryota; Ishima, Tamaki; Kishi, Fukuko; Yasuda, Yuka; Ohi, Kazutaka; Fujimoto, Michiko; Umeda-Yano, Satomi; Ito, Akira; Hashimoto, Kenji; Takeda, Masatoshi
Brain-derived neurotrophic factor (BDNF) regulates the survival and growth of neurons, and influences synaptic efficiency and plasticity. Peripheral BDNF levels in patients with schizophrenia have been widely reported in the literature. However, it is still controversial whether peripheral levels of BDNF are altered in patients with schizophrenia. The peripheral BDNF levels previously reported in patients with schizophrenia were total BDNF (proBDNF and mature BDNF) as it was unable to specifically measure mature BDNF due to limited BDNF antibody specificity. In this study, we examined whether peripheral levels of mature BDNF were altered in patients with treatment-resistant schizophrenia. Matrix metalloproteinase-9 (MMP-9) levels were also measured, as MMP-9 plays a role in the conversion of proBDNF to mature BDNF. Twenty-two patients with treatment-resistant schizophrenia treated with clozapine and 22 age- and sex-matched healthy controls were enrolled. The plasma levels of mature BDNF and MMP-9 were measured using ELISA kits. No significant difference was observed for mature BDNF however, MMP-9 was significantly increased in patients with schizophrenia. The significant correlation was observed between mature BDNF and MMP-9 plasma levels. Neither mature BDNF nor MMP-9 plasma levels were associated clinical variables. Our results do not support the view that peripheral BDNF levels are associated with schizophrenia. MMP-9 may play a role in the pathophysiology of schizophrenia and serve as a biomarker for schizophrenia.
Reimann, Frank; Cox, James J; Belfer, Inna; Diatchenko, Luda; Zaykin, Dmitri V; McHale, Duncan P; Drenth, Joost P H; Dai, Feng; Wheeler, Jerry; Sanders, Frances; Wood, Linda; Wu, Tian-Xia; Karppinen, Jaro; Nikolajsen, Lone; Männikkö, Minna; Max, Mitchell B; Kiselycznyk, Carly; Poddar, Minakshi; Te Morsche, Rene H M; Smith, Shad; Gibson, Dustin; Kelempisioti, Anthi; Maixner, William; Gribble, Fiona M; Woods, C Geoffrey
The gene SCN9A is responsible for three human pain disorders. Nonsense mutations cause a complete absence of pain, whereas activating mutations cause severe episodic pain in paroxysmal extreme pain disorder and primary erythermalgia. This led us to investigate whether single nucleotide polymorphisms (SNPs) in SCN9A were associated with differing pain perception in the general population. We first genotyped 27 SCN9A SNPs in 578 individuals with a radiographic diagnosis of osteoarthritis and a pain score assessment. A significant association was found between pain score and SNP rs6746030; the rarer A allele was associated with increased pain scores compared to the commoner G allele (P = 0.016). This SNP was then further genotyped in 195 pain-assessed people with sciatica, 100 amputees with phantom pain, 179 individuals after lumbar discectomy, and 205 individuals with pancreatitis. The combined P value for increased A allele pain was 0.0001 in the five cohorts tested (1277 people in total). The two alleles of the SNP rs6746030 alter the coding sequence of the sodium channel Nav1.7. Each was separately transfected into HEK293 cells and electrophysiologically assessed by patch-clamping. The two alleles showed a difference in the voltage-dependent slow inactivation (P = 0.042) where the A allele would be predicted to increase Nav1.7 activity. Finally, we genotyped 186 healthy females characterized by their responses to a diverse set of noxious stimuli. The A allele of rs6746030 was associated with an altered pain threshold and the effect mediated through C-fiber activation. We conclude that individuals experience differing amounts of pain, per nociceptive stimulus, on the basis of their SCN9A rs6746030 genotype.
Miksys, Sharon; Lerman, Caryn; Shields, Peter G; Mash, Deborah C; Tyndale, Rachel F
CYP2B6 metabolizes drugs such as nicotine and bupropion, and many toxins and carcinogens. Nicotine induces CYP2B1 in rat brain and in humans polymorphic variation in CYP2B6 affects smoking cessation rates. The aim of this study was to compare CYP2B6 expression in brains of human smokers and non-smokers and alcoholics and non-alcoholics (n=26). CYP2B6 expression was brain region-specific, and was observed in both neurons and astrocytes. CYP2B6 levels were higher in brains of smokers and alcoholics, particularly in cerebellar Purkinje cells and hippocampal pyramidal neurons, cells known to be damaged in alcoholics. Significantly more (penzyme levels, stability and activity. Preliminary genotyping of this small sample (n=24) suggested that individuals with the CC genotype had higher brain CYP2B6 than those with the CT or TT genotype. Higher brain CYP2B6 activity in smokers and alcoholics may cause altered sensitivity to centrally acting drugs, increased susceptibility to neurotoxins and carcinogenic xenobiotics and contribute to central tolerance to nicotine.
Cao, Wenyu; Duan, Juan; Wang, Xueqin; Zhong, Xiaolin; Hu, Zhaolan; Huang, Fulian; Wang, Hongtao; Zhang, Juan; Li, Fang; Zhang, Jianyi; Luo, Xuegang; Li, Chang-Qi
An enriched environment has been shown to influence brain plasticity and function by involving the action of brain-derived neurotrophic factor (BDNF). BDNF, which is synthesized as a precursor molecule (proBDNF) that undergoes proteolytic cleavage, plays an important role in synaptic plasticity and contributes to several brain functions such as memory, learning, and behavior. The neurotrophins and proneurotrophins often play opposite roles in the brain, suggesting that proteolytic cleavage of proneurotrophins controls the action of neurotrophins. However, few studies have focused on the expression and cleavage of proBDNF after exposure to an enriched environment. Our study aimed to explore the effects of an early-enriched environment on the conversion of proBDNF to BDNF in the adult rats' hippocampus. We found that there was no difference in the expression of proBDNF in the hippocampus between the SE (standard environment) and EE (enriched environment) rats, but a significantly increased BDNF protein level was found in the EE rats. Thus, a remarkably enhanced ratio of BDNF to proBDNF (BDNF/proBDNF) was observed in the EE rats. In addition, the EE resulted in a remarkably up-regulated matrix metalloproteinase-9 (MMP-9) in the hippocampus, which played a key role in converting proBDNF to BDNF in the extracellular space. Furthermore, the expression of synapse-related proteins (NR1 and NR2A) was analyzed, and the results indicated that EE could significantly increase the expression of NR1 and NR2A in the hippocampus. In addition, the behavioral results showed that EE reduced anxiety-like behavior in the elevated-plus maze test and reduced immobility time in the forced swimming test. Moreover, the EE resulted in an increased preference for sucrose compared to the SE. These results suggested that the EE up-regulated MMP-9 levels within the hippocampus, which might facilitate the conversion of proBDNF to BDNF, thereby contributing to the long lasting alterations of
Full Text Available Brain-derived neurotrophic factor (BDNF is involved in numerous cognitive functions including learning and memory. BDNF plays an important role in synaptic plasticity in humans and rats with BDNF shown to be essential for the formation of long-term memories. We previously identified a significant association between the BDNF Val66Met polymorphism (rs6265 and long-term visual memory (p-value = 0.003 in a small cohort (n = 181 comprised of healthy individuals who had been phenotyped for various aspects of memory function. In this study, we have extended the cohort to 597 individuals and examined multiple genetic variants across both the BDNF and BDNF-AS genes for association with visual memory performance as assessed by the Wechsler Memory Scale—Fourth Edition subtests Visual Reproduction I and II (VR I and II. VR I assesses immediate visual memory, whereas VR II assesses long-term visual memory. Genetic association analyses were performed for 34 single nucleotide polymorphisms genotyped on Illumina OmniExpress BeadChip arrays with the immediate and long-term visual memory phenotypes. While none of the BDNF and BDNF-AS variants were shown to be significant for immediate visual memory, we found 10 variants (including the Val66Met polymorphism (p-value = 0.006 that were nominally associated, and three variants (two variants in BDNF and one variant in the BDNF-AS locus that were significantly associated with long-term visual memory. Our data therefore suggests a potential role for BDNF, and its anti-sense transcript BDNF-AS, in long-term visual memory performance.
Avgan, Nesli; Sutherland, Heidi G.; Spriggens, Lauren K.; Yu, Chieh; Ibrahim, Omar; Bellis, Claire; Haupt, Larisa M.; Shum, David H. K.; Griffiths, Lyn R.
Brain-derived neurotrophic factor (BDNF) is involved in numerous cognitive functions including learning and memory. BDNF plays an important role in synaptic plasticity in humans and rats with BDNF shown to be essential for the formation of long-term memories. We previously identified a significant association between the BDNF Val66Met polymorphism (rs6265) and long-term visual memory (p-value = 0.003) in a small cohort (n = 181) comprised of healthy individuals who had been phenotyped for various aspects of memory function. In this study, we have extended the cohort to 597 individuals and examined multiple genetic variants across both the BDNF and BDNF-AS genes for association with visual memory performance as assessed by the Wechsler Memory Scale—Fourth Edition subtests Visual Reproduction I and II (VR I and II). VR I assesses immediate visual memory, whereas VR II assesses long-term visual memory. Genetic association analyses were performed for 34 single nucleotide polymorphisms genotyped on Illumina OmniExpress BeadChip arrays with the immediate and long-term visual memory phenotypes. While none of the BDNF and BDNF-AS variants were shown to be significant for immediate visual memory, we found 10 variants (including the Val66Met polymorphism (p-value = 0.006)) that were nominally associated, and three variants (two variants in BDNF and one variant in the BDNF-AS locus) that were significantly associated with long-term visual memory. Our data therefore suggests a potential role for BDNF, and its anti-sense transcript BDNF-AS, in long-term visual memory performance. PMID:28304362
Vinberg, Maj; Miskowiak, Kamilla; Kessing, Lars Vedel
Brain Derived Neurotrophic Factor (BDNF) is a potential biomarker of affective disorder. However, longitudinal studies evaluating a potential predictive role of BDNF on subsequent psychopathology are lacking. The aim of this study was to investigate whether BDNF alone or in interaction...... with the BDNF Val66Met polymorphism predict onset of affective disorder in healthy individuals at heritable risk for affective disorder. In a high-risk study, we assessed whole blood levels of BDNF in 234 healthy monozygotic and dizygotic twins with or without a co-twin history of affective disorder (high...... developed psychiatric disorder. Cox regression analysis revealed that BDNF levels at baseline were not associated with onset of illness in this explorative study. Further, two-way interactions between BDNF levels and the Val66Met polymorphism or between familial risk and the Val66Met polymorphism did...
邵阳; 谢斌; 汪栋祥; 乔屹
Objective To study the association of BDNF related gene polymorphisms with violent behavior in delinquent adolescents. Methods Two single nucleotide polymorphisms (BDNF rsll03010 andrs6265) were detected using TaqMan SNP genotyping assay in 139 violence young male offenders,98 non—violence young male offenders and 259 normal adult controls. The distribution of genotypic and allelic frequencies in the case and control groups was analyzed. Results The results showed that rsll03010 T allelic distribution and rs1103010—rs6265 T—G haplotype were associated with violence behavior (P ＜ 0. 05). Conclusions The variance of BDNF gene polymorphism may play a role under violent behavior in male adolescents.%目的 分析BDNF基因与青少年男性暴力行为之间的关系.方法 采用TaqMan探针SNP基因分型技术对139例男性暴力少教人员,98例非暴力男性少教人员以及259例正常成年男性进行BDNF基因(rs1103010,rs6265)位点的基因分型.分析攻击组和对照组的等位基因和基因型分布规律.结果 器力青少年男性rs1103010位点T等位基因频率高于正常对照组(31.7%vs 24.9%,P＜0.05),rs1103010与rs6265两位点构成的T-G单体型在暴力组中的频率也显著高于正常对照组(31.4%VS 23.4%.P＜0.05).结论 BDNF基因可能在青少年暴力行为的发生中起了作用.
Moriyama, Takaya; Nishii, Rina; Perez-Andreu, Virginia
Widely used as anticancer and immunosuppressive agents, thiopurines have narrow therapeutic indices owing to frequent toxicities, partly explained by TPMT genetic polymorphisms. Recent studies identified germline NUDT15 variation as another critical determinant of thiopurine intolerance, but the ...
Dennis, Nancy A.; Cabeza, Roberto; Need, Anna C.; Waters-Metenier, Sheena; Goldstein, David B.; LaBar, Kevin S.
Brain-derived neurotrophic factor (BDNF) is a neurotrophin which has been shown to regulate cell survival and proliferation, as well as synaptic growth and hippocampal long-term potentiation. A naturally occurring single nucleotide polymorphism in the human BDNF gene (val66met) has been associated with altered intercellular trafficking and regulated secretion of BDNF in met compared to val carriers. Additionally, previous studies have found a relationship between the BDNF val66met genotype and functional activity in the hippocampus during episodic and working memory tasks in healthy young adults. Specifically, studies have found that met carriers exhibit both poorer performance and reduced neural activity within the medial temporal lobe (MTL) when performing episodic memory tasks. However, these studies have not been well replicated and have not considered the role of behavioral differences in the interpretation of neural differences. The current study sought to control for cognitive performance in investigating the role of the BDNF val66met genotype on neural activity associated with episodic memory. Across item and relational memory tests, met carriers exhibited increased MTL activation during both encoding and retrieval stages, compared to non-carriers. The results suggest that met carriers are able to recruit MTL activity to support successful memory processes, and reductions in cognitive performance observed in prior studies are not a ubiquitous effect associated with variants of the BDNF val66met genotype. PMID:20865733
Genetic moderation of child maltreatment effects on depression and internalizing symptoms by serotonin transporter linked polymorphic region (5-HTTLPR), brain-derived neurotrophic factor (BDNF), norepinephrine transporter (NET), and corticotropin releasing hormone receptor 1 (CRHR1) genes in African American children.
Cicchetti, Dante; Rogosch, Fred A
Genetic moderation of the effects of child maltreatment on depression and internalizing symptoms was investigated in a sample of low-income maltreated and nonmaltreated African American children (N = 1,096). Lifetime child maltreatment experiences were independently coded from Child Protective Services records and maternal report. Child depression and internalizing problems were assessed in the context of a summer research camp by self-report on the Children's Depression Inventory and adult counselor report on the Teacher Report Form. DNA was obtained from buccal cell or saliva samples and genotyped for polymorphisms of the following genes: serotonin transporter linked polymorphic region (5-HTTLPR), brain-derived neurotrophic factor (BDNF), norepinephrine transporter, and corticotropin releasing hormone receptor 1. Analyses of covariance with age and gender as covariates were conducted, with maltreatment status and respective polymorphism as main effects and their Gene × Environment (G × E) interactions. Maltreatment consistently was associated with higher Children's Depression Inventory and Teacher Report Form symptoms. The results for child self-report symptoms indicated a G × E interaction for BDNF and maltreatment. In addition, BDNF and triallelic 5-HTTLPR interacted with child maltreatment in a G × G × E interaction. Analyses for counselor report of child anxiety/depression symptoms on the Teacher Report Form indicated moderation of child maltreatment effects by triallelic 5-HTTLPR. These effects were elaborated based on variation in developmental timing of maltreatment experiences. Norepinephrine transporter was found to further moderate the G × E interaction of 5-HTTLPR and maltreatment status, revealing a G × G × E interaction. This G × G × E was extended by consideration of variation in maltreatment subtype experiences. Finally, G × G × E effects were observed for the co-action of BDNF and the corticotropin releasing hormone receptor 1
Full Text Available This paper reviews recent investigations of the influence of dopants on the optical properties of TiO2 polymorphs. The common undoped polymorphs of TiO2 are discussed and compared. The results of recent doping efforts are tabulated, and discussed in the context of doping by elements of the same chemical group. Dopant effects on the band gap and photocatalytic activity are interpreted with reference to a simple qualitative picture of the TiO2 electronic structure, which is supported with first-principles calculations.
Fortress, Ashley M.; Kim, Jaekyoon; Poole, Rachel L.; Gould, Thomas J.; Frick, Karyn M.
Histone acetylation is essential for hippocampal memory formation in young adult rodents. Although dysfunctional histone acetylation has been associated with age-related memory decline in male rodents, little is known about whether histone acetylation is altered by aging in female rodents. In young female mice, the ability of 17ß-estradiol…
Tapia-Arancibia, Lucia; Rage, Florence; Givalois, Laurent; Arancibia, Sandor
Brain-derived neurotrophic factor (BDNF) belongs to the neurotrophin family which interacts with high-affinity protein kinase receptors (Trk) and the unselective p75(NGFR) receptor. The BDNF gene has a complex structure with multiple regulatory elements and four promoters that are differentially expressed in central or peripheral tissue. BDNF expression is regulated by neuronal activity or peripheral hormones. Neurotrophins regulate the survival and differentiation of neurons during development but growing evidence indicates that they are also involved in several functions in adulthood, including plasticity processes. BDNF expression in the central nervous system (CNS) is modified by various kinds of brain insult (stress, ischemia, seizure activity, hypoglycemia, etc.) and alterations in its expression may contribute to some pathologies such as depression, epilepsy, Alzheimer's, and Parkinson's disease. Apart from very traumatic situations, the brain functioning is resilient to stress and capable of adaptive plasticity. Neurotrophins might act as plasticity mediators enhancing this trait which seems to be crucial in adaptive processes. In addition to documenting all of the topics mentioned above in the CNS, we review the state of the art concerning neurotrophins and their receptors, including our personal contribution which is essentially focused on the stress response.
Full Text Available CONTEXT: Alterations of the renin-angiotensin system have been implicated in the pathogenesis of various diseases. The angiotensin converting enzyme is a key enzyme in the renin-angiotensin system. A deletion polymorphism of a 287-bp fragment of intron 16 of the angiotensin converting enzyme gene allele results in higher levels of circulating enzyme. ACE deletion genotype has been linked to heart diseases, sarcoidosis and liver fibrosis. The pancreatic renin-angiotensin system plays a role in the development of pancreatic fibrosis and ACE inhibitors decrease pancreatic fibrosis in experimental models. OBJECTIVES: We investigated the frequency of the ACE gene insertion/deletion polymorphism in chronic pancreatitis patients and controls. PATIENTS: Subjects with familial pancreatitis (n=51, sporadic chronic pancreatitis (n=104, and healthy controls (n=163 were evaluated. MAIN OUTCOME MEASURE: The presence of ACE insertion/deletion polymorphism. RESULTS: The frequency of the ACE gene deletion allele was similar in familial pancreatitis (49.0% sporadic pancreatitis (51.0% and controls (55.8%. Furthermore, there was no significant difference in clinical features between patients with ACE-insertion or insertion/deletion genotypes vs. patients with ACE-deletion genotype. CONCLUSION: We conclude that the ACE deletion genotype does not make a significant contribution to the pathogenesis and the progression of chronic pancreatitis.
Reimann, F.; Cox, J.J.; Belfer, I.; Diatchenko, L.; Zaykin, D.V.; McHale, D.P.; Drenth, J.P.H.; Dai, F.; Wheeler, J.; Sanders, F.; Wood, L.; Wu, T.X.; Karppinen, J.; Nikolajsen, L.; Mannikko, M.; Max, M.B.; Kiselycznyk, C.; Poddar, M.; Morsche, R.H.M. te; Smith, S.; Gibson, D.; Kelempisioti, A.; Maixner, W.; Gribble, F.M.; Woods, C.G.
The gene SCN9A is responsible for three human pain disorders. Nonsense mutations cause a complete absence of pain, whereas activating mutations cause severe episodic pain in paroxysmal extreme pain disorder and primary erythermalgia. This led us to investigate whether single nucleotide polymorphisms
Berghauzen-Maciejewska, Klemencja; Wardas, Jadwiga; Kosmowska, Barbara; Głowacka, Urszula; Kuter, Katarzyna; Ossowska, Krystyna
Our recent study has indicated that a moderate lesion of the mesostriatal and mesolimbic pathways in rats, modelling preclinical stages of Parkinson's disease, induces a depressive-like behaviour which is reversed by chronic treatment with pramipexole. The purpose of the present study was to examine the role of brain derived neurotrophic factor (BDNF) signalling in the aforementioned model of depression. Therefore, we investigated the influence of 6-hydoxydopamine (6-OHDA) administration into the ventral region of the caudate-putamen on mRNA levels of BDNF and tropomyosin-related kinase B (trkB) receptor. The BDNF and trkB mRNA levels were determined in the nigrostriatal and limbic structures by in situ hybridization 2 weeks after the operation. Pramipexole (1 mg/kg sc twice a day) and imipramine (10 mg/kg ip once a day) were injected for 2 weeks. The lesion lowered the BDNF and trkB mRNA levels in the hippocampus [CA1, CA3 and dentate gyrus (DG)] and amygdala (basolateral/lateral) as well as the BDNF mRNA content in the habenula (medial/lateral). The lesion did not influence BDNF and trkB expression in the caudate-putamen, substantia nigra, nucleus accumbens (shell and core) and ventral tegmental area (VTA). Chronic imipramine reversed the lesion-induced decreases in BDNF mRNA in the DG. Chronic pramipexole increased BDNF mRNA, but decreased trkB mRNA in the VTA in lesioned rats. Furthermore, it reduced BDNF and trkB mRNA expression in the shell and core of the nucleus accumbens, BDNF mRNA in the amygdala and trkB mRNA in the caudate-putamen in these animals. The present study indicates that both the 6-OHDA-induced dopaminergic lesion and chronic pramipexole influence BDNF signalling in limbic structures, which may be related to their pro-depressive and antidepressant activity in rats, respectively.
Full Text Available Our recent study has indicated that a moderate lesion of the mesostriatal and mesolimbic pathways in rats, modelling preclinical stages of Parkinson's disease, induces a depressive-like behaviour which is reversed by chronic treatment with pramipexole. The purpose of the present study was to examine the role of brain derived neurotrophic factor (BDNF signalling in the aforementioned model of depression. Therefore, we investigated the influence of 6-hydoxydopamine (6-OHDA administration into the ventral region of the caudate-putamen on mRNA levels of BDNF and tropomyosin-related kinase B (trkB receptor. The BDNF and trkB mRNA levels were determined in the nigrostriatal and limbic structures by in situ hybridization 2 weeks after the operation. Pramipexole (1 mg/kg sc twice a day and imipramine (10 mg/kg ip once a day were injected for 2 weeks. The lesion lowered the BDNF and trkB mRNA levels in the hippocampus [CA1, CA3 and dentate gyrus (DG] and amygdala (basolateral/lateral as well as the BDNF mRNA content in the habenula (medial/lateral. The lesion did not influence BDNF and trkB expression in the caudate-putamen, substantia nigra, nucleus accumbens (shell and core and ventral tegmental area (VTA. Chronic imipramine reversed the lesion-induced decreases in BDNF mRNA in the DG. Chronic pramipexole increased BDNF mRNA, but decreased trkB mRNA in the VTA in lesioned rats. Furthermore, it reduced BDNF and trkB mRNA expression in the shell and core of the nucleus accumbens, BDNF mRNA in the amygdala and trkB mRNA in the caudate-putamen in these animals. The present study indicates that both the 6-OHDA-induced dopaminergic lesion and chronic pramipexole influence BDNF signalling in limbic structures, which may be related to their pro-depressive and antidepressant activity in rats, respectively.
Jin, Peng; Andiappan, Anand Kumar; Quek, Jia Min; Lee, Bernett; Au, Bijin; Sio, Yang Yie; Irwanto, Astrid; Schurmann, Claudia; Grabe, Hans Joergen; Suri, Bani Kaur; Matta, Sri Anusha; Westra, Harm-Jan; Franke, Lude; Esko, Tonu; Sun, Liangdan; Zhang, Xuejun; Liu, Hong; Zhang, Furen; Larbi, Anis; Xu, Xin; Poidinger, Michael; Liu, Jianjun; Chew, Fook Tim; Rotzschke, Olaf; Shi, Li; Wang, De Yun
Background: Brain-derived neurotrophic factor (BDNF) is a secretory protein that has been implicated in the pathogenesis of allergic rhinitis (AR), atopic asthma, and eczema, but it is currently unknown whether BDNF polymorphisms influence susceptibility to moderate-to-severe AR. Objective: We sough
Yang, Jianmin; Siao, Chia-Jen; Nagappan, Guhan; Marinic, Tina; Jing, Deqiang; McGrath, Kelly; Chen, Zhe-Yu; Mark, Willie; Tessarollo, Lino; Lee, Francis S.; Lu, Bai; Hempstead, Barbara L.
Pro–brain-derived neurotrophic factor (proBDNF) and mature BDNF utilize distinct receptors to mediate divergent neuronal actions. Using new tools to quantitate endogenous BDNF isoforms, we found that mouse neurons secrete both proBDNF and mature BDNF. The highest levels of proBDNF and p75 were observed perinatally and declined, but were still detectable, in adulthood. Thus, BDNF actions are developmentally regulated by secretion of proBDNF or mature BDNF and by local expression of p75 and Trk...
BDNF gene polymorphism, cognition and symptom severity in a Brazilian population-based sample of first-episode psychosis subjects Polimorfismo do gene do BDNF, cognição e gravidade dos sintomas em uma amostra de base populacional brasileira de indivíduos apresentando o primeiro episódio psicótico
Eduardo Martinho Jr
Full Text Available OBJECTIVE: To investigate the influence of brain-derived neurotrophic factor (BDNF gene variations on cognitive performance and clinical symptomatology in first-episode psychosis (FEP. METHODS: We performed BDNF val66met variant genotyping, cognitive testing (verbal fluency and digit spans and assessments of symptom severity (as assessed with the PANSS in a population-based sample of FEP patients (77 with schizophreniform psychosis and 53 with affective psychoses and 191 neighboring healthy controls. RESULTS: There was no difference in the proportion of Met allele carriers between FEP patients and controls, and no significant influence of BDNF genotype on cognitive test scores in either of the psychosis groups. A decreased severity of negative symptoms was found in FEP subjects that carried a Met allele, and this finding reached significance for the subgroup with affective psychoses (p OBJETIVO: Investigar a influência da variação do gene do fator neurotrófico derivado do cérebro (BDNF no desempenho cognitivo e na sintomatologia clínica durante o primeiro episódio psicótico (PEP. MÉTODOS: Foram realizados a genotipificação das variantes Val66met do BDNF, o teste cognitivo (fluência verbal e repetição de dígitos e as avaliações da gravidade dos sintomas (conforme avaliado pela Positive and Negative Syndrome Scale [PANSS] em uma amostra de pacientes com PEP de base populacional (77 com psicose esquizofreniforme e 53 com psicose afetiva e 191 vizinhos controle saudáveis. RESULTADOS: Não houve diferença na proporção de portadores do alelo Met entre pacientes com PEP e o grupo controle. Não houve influência significativa do genótipo do BDNF sobre a pontuação de cada um dos grupos psicóticos. Foi encontrada uma diminuição da gravidade dos sintomas negativos em sujeitos com PEP portadores do alelo Met, e essa descoberta mostrou-se significativa para o subgrupo com psicose afetiva (p < 0,01, ANOVA. CONCLUSÕES: Os
Alharbi, Khalid Khalaf; Syed, Rabbani; Khan, Imran Ali
Rising levels of obesity are a global problem that is being exported from affluent to developing nations through the gradual "westernization of lifestyle". Population of Saudi Arabia is going through a nutrition transition where customary and traditional food is being replaced by fast food high in fat, sugar and salt. Interleukin-6 (IL-6) is a central player in the regulation of inflammation, haematopoiesis, immune response and host defense mechanisms. During the last decade, an accumulating amount of data suggested a pivotal role for IL-6 in metabolic processes, thus fortifying the picture of IL-6 as a multifaceted, pleiotropic cytokine. The Objective is to investigate the relationship between IL-6 (rs1554606) polymorphism and the risk of obesity in young Saudi population. Totally 204 Saudi young obese subjects were involved in this study. Genotyping of IL-6 was performed by the real-time polymerase chain reaction technology, using the Taq Man 5'-allele discrimination assay. IL-6 (rs1554606) AA versus AG (p 0.5). We have observed significant effects for Genotyping, LDL, CHOL, AST, ALP, BILIT, BMI at 5% (0.05) significance level in the study population. Our results shown that IL-6 polymorphism have significantly differ in both male and females subjects. We have observed that some evidence of interactions of the IL-6 polymorphism and have shown statistical significant association with elevated BMI, Lipid profile and total bilurubin in the study subjects.
Zhi-Hong Xian; Wen-Ming Cong; Shu-Hui Zhang; Meng-Chao Wu
AIM: To study the genetic alterations and their association with clinicopathological characteristics of hepatocellular carcinoma (HCC), and to find the tumor related DNA fragments.METHODS: DNA isolated from tumors and corresponding noncancerous liver tissues of 56 HCC patients was amplified by random amplified polymorphic DNA (RAPD)with 10 random 10-mer arbitrary primers. The RAPD bands showing obvious differences in tumor tissue DNA corresponding to that of normal tissue were separated,purified, cloned and sequenced. DNA sequences were analyzed and compared with GenBank data.RESULTS: A total of 56 cases of HCC were demonstrated to have genetic alterations, which were detected by at least one primer. The detestability of genetic alterations ranged from 20% to 70% in each case, and 17.9% to 50% in each primer. Serum HBV infection, tumor size,histological grade, tumor capsule, as well as tumor intrahepatic metastasis, might be correlated with genetic alterations on certain primers. A band with a higher intensity of 480 bp or so amplified fragments in tumor DNA relative to normal DNA could be seen in 27 of 56 tumor samples using primer 4. Sequence analysis of these fragments showed 91% homology with Homo sapiens double homeobox protein DUX10 gene.CONCLUSION: Genetic alterations are a frequent event in HCC, and tumor related DNA fragments have been found in this study, which may be associated with hepatocarcinogenesis. RAPD is an effective method for the identification and analysis of genetic alterations in HCC, and may provide new information for further evaluating the molecular mechanism of hepatocarcinogenesis.
Full Text Available The association between BDNF gene functional Val66Met polymorphism rs6265 and the schizophrenia is far from being consistent. In addition to the heterogeneous in schizophrenia per se leading to the inconsistent results, the interaction among multi-genes is probably playing the main role in the pathogenesis of schizophrenia, but not a single gene. Neurotrophic tyrosine kinase receptor 2 (NTRK2 is the high-affinity receptor of BDNF, and was reported to be associated with mood disorders, though no literature reported the association with schizophrenia. Thus, in the present study, total 402 patients with paranoid schizophrenia (the most common subtype of schizophrenia and matched 406 healthy controls were recruited to investigate the role of rs6265 in BDNF, three polymorphisms in NTRK2 gene (rs1387923, rs2769605 and rs1565445 and their interaction in the susceptibility to paranoid schizophrenia in a Chinese Han population. We did not observe significant differences in allele and genotype frequencies between patients and healthy controls for all four polymorphisms separately. The haplotype analysis also showed no association between haplotype of NTRK2 genes (rs1387923, rs2769605, and rs1565445 and paranoid schizophrenia. However, we found the association between the interaction of BDNF and NTRK2 with paranoid schizophrenia by using the MDR method followed by conventional statistical analysis. The best gene-gene interaction model was a three-locus model (BDNF rs6265, NTRK2 rs1387923 and NTRK2 rs2769605, in which one low-risk and three high-risk four-locus genotype combinations were identified. Our findings implied that single polymorphism of rs6265 rs1387923, rs2769605, and rs1565445 in BDNF and NTRK2 were not associated with the development of paranoid schizophrenia in a Han population, however, the interaction of BDNF and NTRK2 genes polymorphisms (BDNF-rs6265, NTRK2-rs1387923 and NTRK2-rs2769605 may be involved in the susceptibility to paranoid
Lin, Zheng; Su, Yousong; Zhang, Chengfang; Xing, Mengjuan; Ding, Wenhua; Liao, Liwei; Guan, Yangtai; Li, Zezhi; Cui, Donghong
The association between BDNF gene functional Val66Met polymorphism rs6265 and the schizophrenia is far from being consistent. In addition to the heterogeneous in schizophrenia per se leading to the inconsistent results, the interaction among multi-genes is probably playing the main role in the pathogenesis of schizophrenia, but not a single gene. Neurotrophic tyrosine kinase receptor 2 (NTRK2) is the high-affinity receptor of BDNF, and was reported to be associated with mood disorders, though no literature reported the association with schizophrenia. Thus, in the present study, total 402 patients with paranoid schizophrenia (the most common subtype of schizophrenia) and matched 406 healthy controls were recruited to investigate the role of rs6265 in BDNF, three polymorphisms in NTRK2 gene (rs1387923, rs2769605 and rs1565445) and their interaction in the susceptibility to paranoid schizophrenia in a Chinese Han population. We did not observe significant differences in allele and genotype frequencies between patients and healthy controls for all four polymorphisms separately. The haplotype analysis also showed no association between haplotype of NTRK2 genes (rs1387923, rs2769605, and rs1565445) and paranoid schizophrenia. However, we found the association between the interaction of BDNF and NTRK2 with paranoid schizophrenia by using the MDR method followed by conventional statistical analysis. The best gene-gene interaction model was a three-locus model (BDNF rs6265, NTRK2 rs1387923 and NTRK2 rs2769605), in which one low-risk and three high-risk four-locus genotype combinations were identified. Our findings implied that single polymorphism of rs6265 rs1387923, rs2769605, and rs1565445 in BDNF and NTRK2 were not associated with the development of paranoid schizophrenia in a Han population, however, the interaction of BDNF and NTRK2 genes polymorphisms (BDNF-rs6265, NTRK2-rs1387923 and NTRK2-rs2769605) may be involved in the susceptibility to paranoid schizophrenia.
Full Text Available The neurotrophin brain derived neurotrophic factor (BDNF is an important growth factor in the CNS. Deficits in transport of this secretory protein could underlie neurodegenerative diseases. Investigation of disease-related changes in BDNF transport might provide insights into the cellular mechanism underlying, for example, Alzheimer’s disease (AD. To analyze the role of BDNF transport in AD, live cell imaging of fluorescently labeled BDNF was performed in hippocampal neurons of different AD model systems. BDNF and APP colocalized with low incidence in vesicular structures. Anterograde as well as retrograde transport of BDNF vesicles was reduced and these effects were mediated by factors released from hippocampal neurons into the extracellular medium. Transport of BDNF was altered at a very early time point after onset of human APP expression or after acute amyloid-beta(1-42 treatment, while the activity-dependent release of BDNF remained unaffected. Taken together, extracellular cleavage products of APP induced rapid changes in anterograde and retrograde transport of BDNF-containing vesicles while release of BDNF was unaffected by transgenic expression of mutated APP. These early transport deficits might lead to permanently impaired brain functions in the adult brain.
Minocherhomji, Sheroy; Athalye, Arundhati S; Madon, Prochi F
To study the association of chromosomal polymorphic variations with infertility and subfertility.......To study the association of chromosomal polymorphic variations with infertility and subfertility....
Disruption of glucocorticoid receptors in the noradrenergic system leads to BDNF up-regulation and altered serotonergic transmission associated with a depressive-like phenotype in female GR(DBHCre) mice.
Chmielarz, Piotr; Kreiner, Grzegorz; Kot, Marta; Zelek-Molik, Agnieszka; Kowalska, Marta; Bagińska, Monika; Daniel, Władysława Anna; Nalepa, Irena
Recently, we have demonstrated that conditional inactivation of glucocorticoid receptors (GRs) in the noradrenergic system, may evoke depressive-like behavior in female but not male mutant mice (GR(DBHCre) mice). The aim of the current study was to dissect how selective ablation of glucocorticoid signaling in the noradrenergic system influences the previously reported depressive-like phenotype and whether it might be linked to neurotrophic alterations or secondary changes in the serotonergic system. We demonstrated that selective depletion of GRs enhances brain derived neurotrophic factor (BDNF) expression in female but not male GR(DBHCre) mice on both the mRNA and protein levels. The possible impact of the mutation on brain noradrenergic and serotonergic systems was addressed by investigating the tissue neurotransmitter levels under basal conditions and after acute restraint stress. The findings indicated a stress-provoked differential response in tissue noradrenaline content in the GR(DBHCre) female but not male mutant mice. An analogous gender-specific effect was identified in the diminished content of 5-hydroxyindoleacetic acid, the main metabolite of serotonin, in the prefrontal cortex, which suggests down-regulation of this monoamine system in female GR(DBHCre) mice. The lack of GR also resulted in an up-regulation of alpha2-adrenergic receptor (α2-AR) density in the female but not male mutants in the locus coeruleus. We have also confirmed the utility of the investigated model in pharmacological studies, which demonstrates that the depressive-like phenotype of GR(DBHCre) female mice can be reversed by antidepressant treatment with desipramine or fluoxetine, with the latter drug evoking more pronounced effects. Overall, our study validates the use of female GR(DBHCre) mice as an interesting and novel genetic tool for the investigation of the cross-connected mechanisms of depression that is not only based on behavioral phenotypes.
Kronenberg, Golo; Mosienko, Valentina; Gertz, Karen; Alenina, Natalia; Hellweg, Rainer; Klempin, Friederike
The interplay between BDNF signaling and the serotonergic system remains incompletely understood. Using a highly sensitive enzyme-linked immunosorbent assay, we studied BDNF concentrations in hippocampus and cortex of two mouse models of altered serotonin signaling: tryptophan hydroxylase (Tph)2-deficient (Tph2 (-/-)) mice lacking brain serotonin and serotonin transporter (SERT)-deficient (SERT(-/-)) mice lacking serotonin re-uptake. Surprisingly, hippocampal BDNF was significantly elevated in Tph2 (-/-) mice, whereas no significant changes were observed in SERT(-/-) mice. Furthermore, BDNF levels were increased in the prefrontal cortex of Tph2 (-/-) but not of SERT(-/-) mice. Our results emphasize the interaction between serotonin signaling and BDNF. Complete lack of brain serotonin induces BDNF expression.
Full Text Available Disturbances of brain derived neurotrophic factor (BDNF signalling have been implicated in the evolution of depression, which likely arises, in part, as a result of diminished synaptic plasticity. Predictably, given stressor involvement in depression, BDNF is affected by recent stressors as well as stressors such as neglect experienced in early life. The effects of early life maltreatment in altering BDNF signalling may be particularly apparent among those individuals with specific BDNF polymorphisms. We examined whether polymorphisms of the Val66Met genotype might be influential in moderating how early-life events play out with respect to later coping styles, cognitive flexibility and depressive features. Among male and female undergraduate students (N = 124, childhood neglect was highly related to subsequent depressive symptoms. This outcome was moderated by the BDNF polymorphism in the sense that depressive symptoms appeared higher in Met carriers who reported low levels of neglect than in those with the Val/Val allele. However, under conditions of high neglect depressive symptoms only increased in the Val/Val individuals. In effect, the Met polymorphism was associated with depressive features, but did not interact with early life neglect in predicting later depressive features. It was further observed that among the Val/Val individuals, the relationship between neglect and depression was mediated by emotion-focused styles and diminished perceived control, whereas this mediation was not apparent in Met carriers. In contrast to the more typical view regarding this polymorphism, the data are consistent with the perspective that in the presence of synaptic plasticity presumably associated with the Val/Val genotype, neglect allows for the emergence of specific appraisal and coping styles, which are tied to depression. In the case of the reduced degree of neuroplasticity expected in the Met carriers, early life adverse experiences are not tied
Qiao, Hui; An, Shu-Cheng; Xu, Chang
BDNF is widespread existed in CNS and PNS, because of its function in nerve regeneration and restoration, more and more researches focused on the effect of BDNF on neural plasticity in the development of depression and the mechanisms of antidepressant. This article review the basic results and the research trends on BDNF and depression at present, more researches about the interactions of BDNF and proBDNF, BDNF and other transmitters and their receptors should be expected.
BDNF (brain-derived neurotrophic factor) is a member of the nerve growth factor family. It is induced by cortical neurons, and is necessary for survival of striatal neurons in the brain. During development, BDNF promotes the survival and differentiation of selected neuronal populations of the peripheral and central nervous systems. Decreased expression of the BDNF gene is seen in both Alzheimer's and Huntington disease patients. BDNF may play a role in the regulation of stress response and in the biology of mood disorders. Multiple transcript variants encoding distinct isoforms have been described for this gene.
Full Text Available Since its discovery almost three decades ago, the secreted neurotrophin brain-derived neurotrophic factor (BDNF has been firmly implicated in the differentiation and survival of neurons of the CNS. More recently, BDNF has also emerged as an important regulator of synaptogenesis and synaptic plasticity mechanisms underlying learning and memory in the adult CNS. In this review we will discuss our knowledge about the multiple intracellular signalling pathways activated by BDNF, and the role of this neurotrophin in long-term synaptic plasticity and memory formation as well as in synaptogenesis. We will show that maturation of BDNF, its cellular localisation and its ability to regulate both excitatory and inhibitory synapses in the CNS may result in conflicting alterations in synaptic plasticity and memory formation. Lack of a precise knowledge about the mechanisms by which BDNF influences higher cognitive functions and complex behaviours may constitute a severe limitation in the possibility to devise BDNF-based therapeutics for human disorders of the CNS.
Tadahiro; Numakawa; Daisaku; Yokomaku; Misty; Richards; Hiroaki; Hori; Naoki; Adachi; Hiroshi; Kunugi
Brain-derived neurotrophic factor(BDNF),a critical neurotrophin,regulates many neuronal aspects including cell differentiation,cell survival,neurotransmission,and synaptic plasticity in the central nervous system(CNS) .Though BDNF has two types of receptors,high affinity tropomyosin-related kinase(Trk) B and low affinity p75 receptors,BDNF positively exerts its biological effects on neurons via activation of TrkB and of resultant intracellular signaling cascades including mitogenactivated protein kinase/extracellular signal-regulated protein kinase,phospholipase Cγ,and phosphoinositide 3-kinase pathways.Notably,it is possible that alteration in the expression and/or function of BDNF in the CNS is involved in the pathophysiology of various brain diseases such as stroke,Parkinson’s disease,Alzheimer’s disease,and mental disorders.On the other hand,glucocorticoids,stress-induced steroid hormones,also putatively contribute to the pathophysiology of depression.Interestingly,in addition to the reduction in BDNF levels due to increased glucocorticoid exposure,current reports demonstrate possible interactions between glucocorticoids and BDNF-mediated neuronal functions. Other steroid hormones,such as estrogen,are involved in not only sexual differentiation in the brain,but also numerous neuronal events including cell survival and synaptic plasticity.Furthermore,it is well known that estrogen plays a role in the pathophysiology of Parkinson’s disease,Alzheimer’s disease,and mental illness,while serving to regulate BDNF expression and/or function.Here,we present a broad overview of the current knowledge concerning the association between BDNF expression/function and steroid hormones(glucocorticoids and estrogen).
Ferreira, Gabriela K; Scaini, Giselli; Jeremias, Isabela C; Carvalho-Silva, Milena; Gonçalves, Cinara L; Pereira, Talita C B; Oliveira, Giovanna M T; Kist, Luiza W; Bogo, Maurício R; Schuck, Patrícia F; Ferreira, Gustavo C; Streck, Emilio L
Tyrosinemia type II, which is also known as Richner-Hanhart syndrome, is an inborn error of metabolism that is due to a block in the transamination reaction that converts tyrosine to p-hydroxyphenylpyruvate. Because the mechanisms of neurological dysfunction in hypertyrosinemic patients are poorly known and the symptoms of these patients are related to the central nervous system, the present study evaluated brain-derived neurotrophic factor (BDNF) levels and bdnf mRNA expression in young rats and during growth. In our acute protocol, Wistar rats (10 and 30 days old) were killed 1 h after a single intraperitoneal L-tyrosine injection (500 mg/kg) or saline. Chronic administration consisted of L-tyrosine (500 mg/kg) or saline injections 12 h apart for 24 days in Wistar rats (7 days old), and the rats were killed 12 h after the last injection. The brains were rapidly removed, and we evaluated the BDNF levels and bdnf mRNA expression. The present results showed that the acute administration of L-tyrosine decreased both BDNF and bdnf mRNA levels in the striatum of 10-day-old rats. In the 30-day-old rats, we observed decreased BDNF levels without modifications in bdnf transcript level in the hippocampus and striatum. Chronic administration of L-tyrosine increased the BDNF levels in the striatum of rats during their growth, whereas bdnf mRNA expression was not altered. We hypothesize that oxidative stress can interact with the BDNF system to modulate synaptic plasticity and cognitive function. The present results enhance our knowledge of the pathophysiology of hypertyrosinemia.
Valente, Nina Leão Marques; Vallada, Homero; Cordeiro, Quirino; Miguita, Karen; Bressan, Rodrigo Affonseca; Andreoli, Sergio Baxter; Mari, Jair Jesus; Mello, Marcelo Feijó
Posttraumatic stress disorder (PTSD) is a prevalent, disabling anxiety disorder marked by behavioral and physiologic alterations which commonly follows a chronic course. Exposure to a traumatic event constitutes a necessary, but not sufficient, factor. There is evidence from twin studies supporting a significant genetic predisposition to PTSD. However, the precise genetic loci still remain unclear. The objective of the present study was to identify, in a case-control study, whether the brain-derived neurotrophic factor (BDNF) val66met polymorphism (rs6265), the dopamine transporter (DAT1) three prime untranslated region (3'UTR) variable number of tandem repeats (VNTR), and the serotonin transporter (5-HTTPRL) short/long variants are associated with the development of PTSD in a group of victims of urban violence. All polymorphisms were genotyped in 65 PTSD patients as well as in 34 victims of violence without PTSD and in a community control group (n = 335). We did not find a statistical significant difference between the BDNF val66met and 5-HTTPRL polymorphism and the traumatic phenotype. However, a statistical association was found between DAT1 3'UTR VNTR nine repeats and PTSD (OR = 1.82; 95% CI, 1.20-2.76). This preliminary result confirms previous reports supporting a susceptibility role for allele 9 and PTSD.
Hao-Jiang Zuo; Zhi-Mei Xie; Wei-Wei Zhang; Yong-Ru Li; Wei Wang; Xiao-Bei Ding; Xiao-Fang Pei
AIM:To investigate the differences in cultivable gut bacteria and peroxisome proliferator-activated receptor γ2 (PPAR-γ2 ) gene Pro12Ala variation in obese and normal-weight Chinese people. METHODS:Using culture methods,the amounts of Escherichia coli ,Enterococci ,Bacteroides ,Lactobacilli ,Bifidobacteria and Clostridium perfringens (C.perfringens ) in the feces of 52 obese participants [body mass index (BMI):≥ 28 kg/m2] and 52 participants of normalweight (BMI:18.5-24 kg/m2) were obtained.Study participants completed comprehensive questionnaires and underwent clinical laboratory tests.The polymerase chain reaction-restriction fragment length polymorphism (PCR-PFLP) assay was used to analyze PPAR-γ2 gene Pro12Ala variation. RESULTS:The obese group exhibited a lower amount of C.perfringens (6.54 ± 0.65 vs 6.94 ± 0.57,P = 0.001) and Bacteroides (9.81 ± 0.58 vs 10.06 ± 0.39,P = 0.012) than their normal-weight counterparts.No major differences were observed in Pro12Ala genotype distribution between the two groups; however,obese individuals with a Pro/Ala genotype had a significantly lower level of Bacteroides (9.45 ± 0.62 vs 9.93 ± 0.51,P = 0.027) than those with a Pro/Pro genotype.In addition, the obese group demonstrated a higher stool frequency (U = 975,P < 0.001) and a looser stool (U = 1062,P = 0.015) than the normal-weight group. CONCLUSION:Our results indicated interactions among cultivable gut flora,host genetic factors and obese phenotype and this might be helpful for obesity prevention.
Full Text Available Liver fatty acid-binding protein (L-FABP, also known as fatty acid-binding protein 1 (FABP1, is a key regulator of hepatic lipid metabolism. Elevated FABP1 levels are associated with an increased risk of cardiovascular disease (CVD and metabolic syndromes. In this study, we examine the association of FABP1 gene promoter variants with serum FABP1 and lipid levels in a Chinese population. Four promoter single-nucleotide polymorphisms (SNPs of FABP1 gene were genotyped in a cross-sectional survey of healthy volunteers (n = 1,182 from Fuzhou city of China. Results showed that only the rs2919872 G>A variant was significantly associated with serum TG concentration(P = 0.032.Compared with the rs2919872 G allele, rs2919872 A allele contributed significantly to reduced serum TG concentration, and this allele dramatically decreased the FABP1 promoter activity(P < 0.05. The rs2919872 A allele carriers had considerably lower serum FABP1 levels than G allele carriers (P < 0.01. In the multivariable linear regression analysis, the rs2919872 A allele was negatively associated with serum FABP1 levels (β = -0.320, P = 0.003, while serum TG levels were positively associated with serum FABP1 levels (β = 0.487, P = 0.014. Our data suggest that compared with the rs2919872 G allele, the rs2919872 A allele reduces the transcriptional activity of FABP1 promoter, and thereby may link FABP1 gene variation to TG level in humans.
Full Text Available BACKGROUND: Brain derived neurotrophic factor (BDNF has been shown to play an important role in poststroke recovery. BDNF secretion is influenced by genetic and epigenetic profiles. This study aimed to investigate whether BDNF val66met polymorphism and promoter methylation status were associated with outcomes at two weeks and one year after stroke. METHODS AND FINDINGS: A total of 286 patients were evaluated at the time of admission and two weeks after stroke, and 222 (78% were followed one year later in order to evaluate consequences of stroke at both acute and chronic stages. Stroke outcomes were dichotomised into good and poor by the modified Rankin Scale. Stroke severity (National Institutes of Health Stroke Scale, physical disability (Barthel Index, and cognitive function (Mini-Mental State Examination were measured. Associations of BDNF genotype and methylation status on stroke outcomes and assessment scale scores were investigated using logistic regression, repeated measures ANOVA and partial correlation tests. BDNF val66met polymorphism was independently associated with poor outcome at 2 weeks and at 1 year, and with worsening physical disability and cognitive function over that period. Higher BDNF promoter methylation status was independently associated with worse outcomes at 1 year, and with the worsening of physical disability and cognitive function. No significant genotype-methylation interactions were found. CONCLUSIONS: A role for BDNF in poststroke recovery was supported, and clinical utility of BDNF genetic and epigenetic profile as prognostic biomarkers and a target for drug development was suggested.
抑郁症患者无抽搐电休克治疗的疗效与脑源性神经营养因子基因多态性%Relationship between the effect of modified electroconvulsive therapy and brain-derived neurotrophic factor(BDNF) gene polymorphism in patients with major depressive disorder
楼丹丹; 况利; 李大奇; 甘窈; 艾明; 高新学
目的:探讨抑郁症患者脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)基因两个单核苷酸多态性位点的多态性与无抽搐电休克治疗(modified electroconvulsive therapy,MECT)疗效的关系.方法:采用病例对照研究,研究组为110例符合美国精神障碍诊断统计手册第4版(Diagnostic and Statistical Manual of Mental Disorders,Fourth Edition,DSM-IV)抑郁症诊断标准的门诊及住院患者,对照组为100名正常人.患者入组后连续接受MECT 8次,使用汉密顿抑郁量表(Hamilton Depression Rat.ing Scale for Depression,HRSD)进行抑郁严重程度及疗效评估.运用PCR扩增及测序的方法,分析BD-NF基因rs6265、rs7103411单核苷酸多态性的分布,分析rs6265、rs7103411基因型及等位基因频率分布与MECT疗效的关系.结果:BDNF基因rs6265、rs7103411位点基因型及等位基因频率在对照组与患者组间的差异无统计学意义,MECT后2个位点基因型及rs710341I等位基因频率在不同疗效组间的差异无统计学意义.rs6265位点A等位基因频率和G等位基因频率在减分率I>50%组分别为47.9%、52.1%;在减分率<25%组分别为27.5%、72.5%,两组比较差异有统计学意义(P<0.05),且A等位基因对MECT反应好于G等位基因(OR=1.740,95%CI:1.022～2.963).结论:病情严重的抑郁症患者BDNF基因rs6265位点A等位基因可能与无抽搐电休克治疗效果有关,A等位基因携带者接受MECT的疗效较G等位基因携带者好.%Objective To explore the relation of brain-derived neurotrophic factor (BDNF) polymorphisms with the response to modified electroconvulsive therapy (MECT) in patients with major depressive disorder (MDD) . Methods: In this study, 110 patients with major depression were selected according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria, and 100 healthy person were used as controls. The patients received MECT 8 times consecutively and were assessed with
Angelucci, F; Brenè, S; Mathé, A A
Understanding the etiology and pathogenesis schizophrenia and depression is a major challenge facing psychiatry. One hypothesis is that these disorders are secondary to a malfunction of neurotrophic factors. Inappropriate neurotrophic support during brain development could lead to structural disorganisation in which neuronal networks are established in a nonoptimal manner. Inadequate neurotrophic support in adult individuals could ultimately be an underlying mechanism leading to decreased capacity of brain to adaptive changes and increased vulnerability to neurotoxic damage. Brain-derived neurotrophic factor (BDNF) is a mediator involved in neuronal survival and plasticity of dopaminergic, cholinergic, and serotonergic neurons in the central nervous system (CNS). In this review, we summarize findings regarding altered BDNF in schizophrenia and depression and animal models, as well as the effects of antipsychotic and antidepressive treatments on the expression of BDNF.
Klein, Anders B; Williamson, Rebecca; Santini, Martin A
Brain-derived neurotrophic factor (BDNF) is involved in synaptic plasticity, neuronal differentiation and survival of neurons. Observations of decreased serum BDNF levels in patients with neuropsychiatric disorders have highlighted the potential of BDNF as a biomarker, but so far there have been...... positive correlation between frontal cortex and hippocampal BDNF levels in mice (r2=0.81, p=0.0139). Our data support the view that measures of blood and plasma BDNF levels reflect brain-tissue BDNF levels....
Fontanari, Anna Martha Vaitses; Costa, Angelo Brandelli; Aguiar, Bianca; Tusset, Cíntia; Andreazza, Tahiana; Schneider, Maiko; da Rosa, Eduarda Dias; Soll, Bianca Machado Borba; Schwarz, Karine; da Silva, Dhiordan Cardoso; Borba, André Oliveira; Mueller, Andressa; Massuda, Raffael; Lobato, Maria Inês Rodrigues
Serum BDNF levels are significantly decreased in transsexual Brazilian women when compared to cis-sexual men. Since transsexual men are also exposed to chronic social stress and have a high prevalence of associated psychopathologies, it is plausible to inquire if BDNF serum levels are altered in transsexual men as well. Therefore, our objective was to evaluate differences in BDNF serum level of transsexual men when compared to cis-sexual men and women. Our sample comprises 27 transsexual men, 31 cis-sexual women and 30 cis-sexual men recruited between 2011 and 2015. We observed that BDNF serum concentration is decreased in transsexual men comparing to cis-sexual men and women. Cross-sex hormone treatment, chronic social stress or long-term gender dysphoria (GD) could explain the variation found in BDNF serum levels.
Klemencja Berghauzen-Maciejewska; Jadwiga Wardas; Barbara Kosmowska; Urszula Głowacka; Katarzyna Kuter; Krystyna Ossowska
Our recent study has indicated that a moderate lesion of the mesostriatal and mesolimbic pathways in rats, modelling preclinical stages of Parkinson's disease, induces a depressive-like behaviour which is reversed by chronic treatment with pramipexole. The purpose of the present study was to examine the role of brain derived neurotrophic factor (BDNF) signalling in the aforementioned model of depression. Therefore, we investigated the influence of 6-hydoxydopamine (6-OHDA) administration into...
Fritsch, Brita; Reis, Janine; Martinowich, Keri; Schambra, Heidi M; Ji, Yuanyuan; Cohen, Leonardo G; Lu, Bai
Despite its increasing use in experimental and clinical settings, the cellular and molecular mechanisms underlying transcranial direct current stimulation (tDCS) remain unknown. Anodal tDCS applied to the human motor cortex (M1) improves motor skill learning. Here, we demonstrate in mouse M1 slices that DCS induces a long-lasting synaptic potentiation (DCS-LTP), which is polarity specific, NMDA receptor dependent, and requires coupling of DCS with repetitive low-frequency synaptic activation (LFS). Combined DCS and LFS enhance BDNF-secretion and TrkB activation, and DCS-LTP is absent in BDNF and TrkB mutant mice, suggesting that BDNF is a key mediator of this phenomenon. Moreover, the BDNF val66met polymorphism known to partially affect activity-dependent BDNF secretion impairs motor skill acquisition in humans and mice. Motor learning is enhanced by anodal tDCS, as long as activity-dependent BDNF secretion is in place. We propose that tDCS may improve motor skill learning through augmentation of synaptic plasticity that requires BDNF secretion and TrkB activation within M1.
Janke, Kellie L; Cominski, Tara P; Kuzhikandathil, Eldo V; Servatius, Richard J; Pang, Kevin C H
Dysregulation of brain-derived neurotrophic factor (BDNF), behavioral inhibition temperament (BI), and small hippocampal volume have been linked to anxiety disorders. Individuals with BI show facilitated acquisition of the classically conditioned eyeblink response (CCER) as compared to non-BI individuals, and a similar pattern is seen in an animal model of BI, the Wistar-Kyoto (WKY) rat. The present study examined the role of hippocampal BDNF in the facilitated delay CCER of WKY rats. Consistent with earlier work, acquisition was facilitated in WKY rats compared to the Sprague Dawley (SD) rats. Facilitated acquisition was associated with increased BDNF, TrkB, and Arc mRNA in the dentate gyrus of SD rats, but learning-induced increases in BDNF and Arc mRNA were significantly smaller in WKY rats. To determine whether reduced hippocampal BDNF in WKY rats was a contributing factor for their facilitated CCER, BDNF or saline infusions were given bilaterally into the dentate gyrus region 1 h prior to training. BDNF infusion did not alter the acquisition of SD rats, but significantly dampened the acquisition of CCER in the WKY rats, such that acquisition was similar to SD rats. Together, these results suggest that inherent differences in the BDNF system play a critical role in the facilitated associative learning exhibited by WKY rats, and potentially individuals with BI. Facilitated associative learning may represent a vulnerability factor in the development of anxiety disorders.
Kellie L Janke
Full Text Available Dysregulation of brain-derived neurotrophic factor (BDNF, behavioral inhibition temperament (BI and small hippocampal volume have been linked to anxiety disorders. Individuals with BI show facilitated acquisition of the classically conditioned eyeblink response (CCER as compared to non-BI individuals, and a similar pattern is seen in an animal model of BI, the Wistar-Kyoto (WKY rat. The present study examined the role of hippocampal BDNF in the facilitated delay CCER of WKY rats. Consistent with earlier work, acquisition was facilitated in WKY rats compared to the SD rats. Facilitated acquisition was associated with increased BDNF, TrkB, and Arc mRNA in the dentate gyrus of SD rats, but learning-induced increases in BDNF and Arc mRNA were significantly smaller in WKY rats. To determine if reduced hippocampal BDNF in WKY rats was a contributing factor for their facilitated CCER, BDNF or saline infusions were given bilaterally into the dentate gyrus region one hour prior to training. BDNF infusion did not alter the acquisition of SD rats, but significantly dampened the acquisition of CCER in the WKY rats, such that acquisition was similar to SD rats. Together, these results suggest that inherent differences in the BDNF system play a critical role in the facilitated associative learning exhibited by WKY rats, and potentially individuals with BI. Facilitated associative learning may represent a vulnerability factor in the development of anxiety disorders.
Full Text Available It is essential to understand the molecular processes underlying long-term memory to provide therapeutic targets of aberrant memory that produce pathological behaviour in humans. Under conditions of recall, fully-consolidated memories can undergo reconsolidation or extinction. These retrieval-mediated memory processes may rely on distinct molecular processes. The cellular mechanisms initiating the signature molecular events are not known. Using infusions of protein synthesis inhibitors, antisense oligonucleotide targeting brain-derived neurotrophic factor (BDNF mRNA or tPA-STOP (an inhibitor of the proteolysis of BDNF protein into the hippocampus of the awake rat, we show that acquisition and extinction of contextual fear memory depended on the increased and decreased proteolysis of proBDNF (precursor BDNF in the hippocampus, respectively. Conditions of retrieval that are known to initiate the reconsolidation of contextual fear memory, a BDNF-independent memory process, were not correlated with altered proBDNF cleavage. Thus, the processing of BDNF was associated with the acquisition of new information and the updating of information about a salient stimulus. Furthermore, the differential requirement for the processing of proBDNF by tPA in distinct memory processes suggest that the molecular events actively engaged to support the storage and/or the successful retrieval of memory depends on the integration of ongoing experience with past learning.
Rachel L. Miller
Full Text Available Prenatal exposure to polycyclic aromatic hydrocarbons (PAH has been associated with sustained effects on the brain and behavior in offspring. However, the mechanisms have yet to be determined. We hypothesized that prenatal exposure to ambient PAH in mice would be associated with impaired neurocognition, increased anxiety, altered cortical expression of Bdnf and Grin2b, and greater DNA methylation of Bdnf. Our results indicated that during open-field testing, prenatal PAH–exposed offspring spent more time immobile and less time exploring. Females produced more fecal boli. Offspring prenatally exposed to PAH displayed modest reductions in overall exploration of objects. Further, prenatal PAH exposure was associated with lower cortical expression of Grin2b and Bdnf in males and greater Bdnf IV promoter methylation. Epigenetic differences within the Bdnf IV promoter correlated with Bdnf gene expression but not with the observed behavioral outcomes, suggesting that additional targets may account for these PAH-associated effects.
Christine T Shiner
Full Text Available Background. Persistent motor impairment is common but highly heterogeneous post-stroke. Genetic polymorphisms, including those identified on the brain derived neurotrophic factor (BDNF and apolipoprotein E (APOE genes, may contribute to this variability by limiting the capacity for use-dependent neuroplasticity, and hence rehabilitation responsiveness.Objective. To determine whether BDNF and APOE genotypes influence motor improvement facilitated by post-stroke upper-limb rehabilitation. Methods. BDNF Val66Met and APOE isoform genotypes were determined using leukocyte DNA for 55 community-dwelling patients 2-123 months post-stroke. All patients completed a dose-matched upper-limb rehabilitation program of either Wii-based Movement Therapy or Constraint-induced Movement Therapy. Upper-limb motor-function was assessed pre- and post-therapy using a suite of functional measures. Results. Motor-function improved for all patients post-therapy, with no difference between therapy groups. In the pooled data, there was no significant effect of BDNF or APOE genotype on motor-function at baseline, or following the intervention. However, a significant interaction between the level of residual motor-function and BDNF genotype was identified (p=0.029, whereby post-therapy improvement was significantly less for Met allele carriers with moderate and high, but not low motor-function. There was no significant association between APOE genotype and therapy outcomes. Conclusions. This study identified a novel interaction between the BDNF Val66Met polymorphism, motor-function status and the magnitude of improvement with rehabilitation in chronic stroke. This polymorphism does not preclude, but may reduce, the magnitude of motor improvement with therapy, particularly for patients with higher but not lower residual motor-function. BDNF genotype should be considered in the design and interpretation of clinical trials.
Scassellati, Catia; Zanardini, Roberta; Tiberti, Alessandra; Pezzani, Marco; Valenti, Vera; Effedri, Paola; Filippini, Elena; Conte, Stefano; Ottolini, Alberto; Gennarelli, Massimo; Bocchio-Chiavetto, Luisella
It has been proposed that the neurotrophin brain-derived neurotrophic factor (BDNF) may be involved in attention deficit-hyperactivity disorder (ADHD) etiopathogenesis. Alterations in BDNF serum levels have been observed in childhood/adulthood neurodevelopmental pathologies, but no evidence is available for BDNF serum concentrations in ADHD. The study includes 45 drug-naïve ADHD children and 45 age-sex matched healthy subjects. Concentration of serum BDNF was determined by the ELISA method. BDNF serum levels in patients with ADHD were not different from those of controls (mean ± SD; ADHD: 39.33 ± 10.41 ng/ml; controls: 38.82 ± 8.29 ng/ml, t = -0.26, p = 0.80). Our findings indicate no alteration of serum BDNF levels in untreated patients with ADHD. A further stratification for cognitive, neuropsychological and psychopathological assessment in a larger sample could be useful to clarify the role of BDNF in the endophenotype characterization of ADHD.
Lu, Haitao; Zhang, Tong; Wen, Mei; Sun,Li
Background Little is known about the effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) on dysmnesia and the impact of brain nucleotide neurotrophic factor (BDNF) Val66Met single-nucleotide polymorphism (SNP). This study investigated the impact of low-frequency rTMS on post-stroke dysmnesia and the impact of BDNF Val66Met SNP. Material/Methods Forty patients with post-stroke dysmnesia were prospectively randomized into the rTMS and sham groups. BDNF Val66Met SNP was ...
Klein, Anders B; Williamson, Rebecca; Santini, Martin A;
Brain-derived neurotrophic factor (BDNF) is involved in synaptic plasticity, neuronal differentiation and survival of neurons. Observations of decreased serum BDNF levels in patients with neuropsychiatric disorders have highlighted the potential of BDNF as a biomarker, but so far there have been...... no studies directly comparing blood BDNF levels to brain BDNF levels in different species. We examined blood, serum, plasma and brain-tissue BDNF levels in three different mammalian species: rat, pig, and mouse, using an ELISA method. As a control, we included an analysis of blood and brain tissue from...... conditional BDNF knockout mice and their wild-type littermates. Whereas BDNF could readily be measured in rat blood, plasma and brain tissue, it was undetectable in mouse blood. In pigs, whole-blood levels of BDNF could not be measured with a commercially available ELISA kit, but pig plasma BDNF levels (mean...
Ahmed, Anthony O; Mantini, Andrew M; Fridberg, Daniel J; Buckley, Peter F
Studies suggest that the BDNF Val66Met (rs6265) polymorphism is associated with the incidence of schizophrenia and neurocognitive functioning. These associations appear to be however somewhat mixed. We conducted two separate meta-analyses to investigate (1) the association between the Val66Met polymorphism and neurocognition in people with schizophrenia and (2) the association between peripheral expression of BDNF and neurocognitive phenotypes. For the first aim, we identified 12 studies and 67 comparisons of Met allele carriers and Val homozygotes. These comparisons included 1890 people with schizophrenia (men=1465, women=553), of whom 972 were Met allele carriers and 918 were Val homozygotes. For the second aim, we identified five studies and 25 correlations of peripheral BDNF and neurocognitive scores. The meta-analysis for the second aim included 414 people with schizophrenia (men=292, women=170). First, we found non-significant difference between the genotype groups on most neurocognitive domains. Second, correlations between peripheral BDNF and neurocognitive phenotypes were minimal but we obtained significant effects for the reasoning and problem-solving domains; thus, higher levels of BDNF expression corresponded to better performance on reasoning/problem-solving tasks. The meta-analyses did not robustly establish an association between BDNF Val66Met polymorphism and neurocognition in schizophrenia.
Schildt, Sandra; Endres, Thomas; Lessmann, Volkmar; Edelmann, Elke
Brain-derived neurotrophic factor (BDNF) signaling via TrkB crucially regulates synaptic plasticity in the brain. Although BDNF is abundant at hippocampal mossy fiber (MF) synapses, which critically contribute to hippocampus dependent memory, its role in MF synaptic plasticity (long-term potentiation, LTP) remained largely unclear. Using field potential recordings in CA3 of adult heterozygous BDNF knockout (ko, BDNF+/-) mice we observed impaired (∼50%) NMDAR-independent MF-LTP. In contrast to MF synapses, LTP at neighboring associative/commissural (A/C) fiber synapses remained unaffected. To exclude that impaired MF-LTP in BDNF+/- mice was due to developmental changes in response to chronically reduced BDNF levels, and to prove the importance of acute availability of BDNF in MF-LTP, we also tested effects of acute interference with BDNF/TrkB signaling. Inhibition of TrkB tyrosine kinase signaling with k252a, or with the selective BDNF scavenger TrkB-Fc, both inhibited MF-LTP to the same extent as observed in BDNF+/- mice. Basal synaptic transmission, short-term plasticity, and synaptic fatigue during LTP induction were not significantly altered by treatment with k252a or TrkB-Fc, or by chronic BDNF reduction in BDNF+/- mice. Since the acute interference with BDNF-signaling did not completely block MF-LTP, our results provide evidence that an additional mechanism besides BDNF induced TrkB signaling contributes to this type of LTP. Our results prove for the first time a mechanistic action of acute BDNF/TrkB signaling in presynaptic expression of MF-LTP in adult hippocampus.
White matter alterations related to attention-deficit hyperactivity disorder and COMT val158met polymorphism: children with valine homozygote attention-deficit hyperactivity disorder have altered white matter connectivity in the right cingulum (cingulate gyrus
Kabukcu Basay B
Full Text Available Burge Kabukcu Basay,1 Ahmet Buber,1 Omer Basay,1 Huseyin Alacam,2 Onder Ozturk,1 Serkan Suren,3 Ozlem Izci Ay,4 Cengizhan Acikel,5 Kadir Agladioglu,6 Mehmet Emin Erdal,4 Eyup Sabri Ercan,7 Hasan Herken21Child and Adolescent Psychiatry Department, Pamukkale University Medical Faculty, Denizli, 2Psychiatry Department, Pamukkale University Medical Faculty, Denizli, 3Medical Park Samsun Hospital, Samsun, 4Medical Biology and Genetics Department, Mersin University Medical Faculty, Mersin, 5Biostatistics Department, GATA (GMMA, Ankara, 6Radiology Department, Pamukkale University Medical Faculty, Denizli, 7Child and Adolescent Psychiatry Department, Ege University Medical Faculty, Izmir, TurkeyIntroduction: In this article, the COMT gene val158met polymorphism and attention-deficit hyperactivity disorder (ADHD-related differences in diffusion-tensor-imaging-measured white matter (WM structure in children with ADHD and controls were investigated.Patients and methods: A total of 71 children diagnosed with ADHD and 24 controls aged 8–15 years were recruited. Using diffusion tensor imaging, COMT polymorphism and ADHD-related WM alterations were investigated, and any interaction effect between the COMT polymorphism and ADHD was also examined. The effects of age, sex, and estimated total IQ were controlled by multivariate analysis of covariance (MANCOVA.Results: First, an interaction between the COMT val158met polymorphism and ADHD in the right (R cingulum (cingulate gyrus (CGC was found. According to this, valine (val homozygote ADHD-diagnosed children had significantly lower fractional anisotropy (FA and higher radial diffusivity (RD in the R-CGC than ADHD-diagnosed methionine (met carriers, and val homozygote controls had higher FA and lower RD in the R-CGC than val homozygote ADHD patients. Second, met carriers had higher FA and axial diffusivity in the left (L-uncinate fasciculus and lower RD in the L-posterior corona radiata and L
Andero, R; Ressler, K J
Brain-derived neurotrophic factor (BDNF) is the most studied neurotrophin involved in synaptic plasticity processes that are required for long-term learning and memory. Specifically, BDNF gene expression and activation of its high-affinity tropomyosin-related kinase B (TrkB) receptor are necessary in the amygdala, hippocampus and prefrontal cortex for the formation of emotional memories, including fear memories. Among the psychiatric disorders with altered fear processing, there is post-traumatic stress disorder (PTSD) which is characterized by an inability to extinguish fear memories. Since BDNF appears to enhance extinction of fear, targeting impaired extinction in anxiety disorders such as PTSD via BDNF signalling may be an important and novel way to enhance treatment efficacy. The aim of this review is to provide a translational point of view that stems from findings in the BDNF regulation of synaptic plasticity and fear extinction. In addition, there are different systems that seem to alter fear extinction through BDNF modulation like the endocannabinoid system and the hypothalamic-pituitary adrenal axis. Recent work also finds that the pituitary adenylate cyclase-activating polypeptide and PAC1 receptor, which are upstream of BDNF activation, may be implicated in PTSD. Especially interesting are data that exogenous fear extinction enhancers such as antidepressants, histone deacetylases inhibitors and D-cycloserine, a partial N-methyl d-aspartate agonist, may act through or in concert with the BDNF-TrkB system. Finally, we review studies where recombinant BDNF and a putative TrkB agonist, 7,8-dihydroxyflavone, may enhance extinction of fear. These approaches may lead to novel agents that improve extinction in animal models and eventually humans.
Guo, J.; Ji, Y.; Y. Ding; Jiang, W.; Sun, Y.; B. Lu; Nagappan, G
The precursor of brain-derived neurotrophic factor (BDNF) (proBDNF) is enzymatically cleaved, by either intracellular (furin/PC1) or extracellular proteases (tPA/plasmin/MMP), to generate mature BDNF (mBDNF) and its pro-peptide (BDNF pro-peptide). Little is known about the function of BDNF pro-peptide. We have developed an antibody that specifically detects cleaved BDNF pro-peptide, but not proBDNF or mBDNF. Neuronal depolarization elicited a marked increase in extracellular BDNF pro-peptide,...
Jovel, Irina Tatiana; Kofoed, Poul-Erik; Rombo, Lars; Rodrigues, Amabelia; Ursing, Johan
In 2008, artemether-lumefantrine was introduced in Guinea-Bissau, West Africa, but quinine has also been commonly prescribed for the treatment of uncomplicated Plasmodium falciparum malaria. An efficacious high-dose chloroquine treatment regimen was used previously. Temporal and seasonal changes of genetic polymorphisms associated with altered drug susceptibility to chloroquine, lumefantrine, and quinine have been described. P. falciparum chloroquine resistance transporter (pfcrt) K76T, pfmdr1 gene copy numbers, pfmdr1 polymorphisms N86Y and Y184F, and pfmdr1 sequences 1034 to 1246 were determined using PCR-based methods. Blood samples came from virtually all (n=1,806) childrenquinine and despite a fitness cost linked to pfcrt 76T. (The studies reported here were registered at ClinicalTrials.gov under registration no. NCT00137514 [PSB-2001-chl-amo], NCT00137566 [PSB-2004-paracetamol], NCT00426439 [PSB-2006-coartem], NCT01157689 [AL-eff 2010], and NCT01704508 [Eurartesim 2012].).
Roth, Tania L; Zoladz, Phillip R; Sweatt, J David; Diamond, David M
Epigenetic alterations of the brain-derived neurotrophic factor (Bdnf) gene have been linked with memory, stress, and neuropsychiatric disorders. Here we examined whether there was a link between an established rat model of post-traumatic stress disorder (PTSD) and Bdnf DNA methylation. Adult male Sprague-Dawley rats were given psychosocial stress composed of two acute cat exposures in conjunction with 31 days of daily social instability. These manipulations have been shown previously to produce physiological and behavioral sequelae in rats that are comparable to symptoms observed in traumatized people with PTSD. We then assessed Bdnf DNA methylation patterns (at exon IV) and gene expression. We have found here that the psychosocial stress regimen significantly increased Bdnf DNA methylation in the dorsal hippocampus, with the most robust hypermethylation detected in the dorsal CA1 subregion. Conversely, the psychosocial stress regimen significantly decreased methylation in the ventral hippocampus (CA3). No changes in Bdnf DNA methylation were detected in the medial prefrontal cortex or basolateral amygdala. In addition, there were decreased levels of Bdnf mRNA in both the dorsal and ventral CA1. These results provide evidence that traumatic stress occurring in adulthood can induce CNS gene methylation, and specifically, support the hypothesis that epigenetic marking of the Bdnf gene may underlie hippocampal dysfunction in response to traumatic stress. Furthermore, this work provides support for the speculative notion that altered hippocampal Bdnf DNA methylation is a cellular mechanism underlying the persistent cognitive deficits which are prominent features of the pathophysiology of PTSD.
Vinberg, Maj; Miskowiak, Kamilla; Kessing, Lars Vedel
Brain Derived Neurotrophic Factor (BDNF) is a potential biomarker of affective disorder. However, longitudinal studies evaluating a potential predictive role of BDNF on subsequent psychopathology are lacking. The aim of this study was to investigate whether BDNF alone or in interaction with the BDNF Val66Met polymorphism predict onset of affective disorder in healthy individuals at heritable risk for affective disorder. In a high-risk study, we assessed whole blood levels of BDNF in 234 healthy monozygotic and dizygotic twins with or without a co-twin history of affective disorder (high and low risk twins, respectively). Participants were followed up longitudinally with questionnaires at 6-month intervals for mean seven years and then reassessed with a personal interview to obtain information about whether they had developed psychiatric illness. At follow-up 36 participants (15.4%) had developed psychiatric disorder. Cox regression analysis revealed that BDNF levels at baseline were not associated with onset of illness in this explorative study. Further, two-way interactions between BDNF levels and the Val66Met polymorphism or between familial risk and the Val66Met polymorphism did not predict illness onset.
Buchmann, Arlette F; Hellweg, Rainer; Rietschel, Marcella; Treutlein, Jens; Witt, Stephanie H; Zimmermann, Ulrich S; Schmidt, Martin H; Esser, Günter; Banaschewski, Tobias; Laucht, Manfred; Deuschle, Michael
Recent studies have emphasized an important role for neurotrophins, such as brain-derived neurotrophic factor (BDNF), in regulating the plasticity of neural circuits involved in the pathophysiology of stress-related diseases. The aim of the present study was to examine the interplay of the BDNF Val⁶⁶Met and the serotonin transporter promoter (5-HTTLPR) polymorphisms in moderating the impact of early-life adversity on BDNF plasma concentration and depressive symptoms. Participants were taken from an epidemiological cohort study following the long-term outcome of early risk factors from birth into young adulthood. In 259 individuals (119 males, 140 females), genotyped for the BDNF Val⁶⁶Met and the 5-HTTLPR polymorphisms, plasma BDNF was assessed at the age of 19 years. In addition, participants completed the Beck Depression Inventory (BDI). Early adversity was determined according to a family adversity index assessed at 3 months of age. Results indicated that individuals homozygous for both the BDNF Val and the 5-HTTLPR L allele showed significantly reduced BDNF levels following exposure to high adversity. In contrast, BDNF levels appeared to be unaffected by early psychosocial adversity in carriers of the BDNF Met or the 5-HTTLPR S allele. While the former group appeared to be most susceptible to depressive symptoms, the impact of early adversity was less pronounced in the latter group. This is the first preliminary evidence indicating that early-life adverse experiences may have lasting sequelae for plasma BDNF levels in humans, highlighting that the susceptibility to this effect is moderated by BDNF Val⁶⁶Met and 5-HTTLPR genotype.
Full Text Available Vision loss in glaucoma is caused by progressive dysfunction of retinal ganglion cells (RGCs and optic nerve atrophy. Here, we investigated the effectiveness of BDNF treatment to preserve vision in a glaucoma experimental model. As an established experimental model, we used the DBA/2J mouse, which develops chronic intraocular pressure (IOP elevation that mimics primary open-angle glaucoma (POAG. IOP was measured at different ages in DBA/2J mice. Visual function was monitored using the steady-state Pattern Electroretinogram (P-ERG and visual cortical evoked potentials (VEP. RGC alterations were assessed using Brn3 immunolabeling, and confocal microscope analysis. Human recombinant BDNF was dissolved in physiological solution (0.9% NaCl; the effects of repeated intravitreal injections and topical eye BDNF applications were independently evaluated in DBA/2J mice with ocular hypertension. BDNF level was measured in retinal homogenate by ELISA and western blot. We found a progressive decline of P-ERG and VEP responses in DBA/2J mice between 4 and 7 months of age, in relationship with the development of ocular hypertension and the reduction of Brn3 immunopositive RGCs. Conversely, repeated intravitreal injections (BDNF concentration = 2 µg/µl, volume = 1 µl, for each injection; 1 injection every four days, three injections over two weeks and topical eye application of BDNF eye-drops (12 µg/µl, 5 µl eye-drop every 48 h for two weeks were able to rescue visual responses in 7 month DBA/2J mice. In particular, BDNF topical eye treatment recovered P-ERG and VEP impairment increasing the number of Brn3 immunopositive RGCs. We showed that BDNF effects were independent of IOP reduction. Thus, topical eye treatment with BDNF represents a promisingly safe and feasible strategy to preserve visual function and diminish RGC vulnerability to ocular hypertension.
Full Text Available The fine tuning of neural networks during development and learning relies upon both functional and structural plastic processes. Changes in the number as well as in the size and shape of dendritic spines are associated to long-term activity-dependent synaptic plasticity. However, the molecular mechanisms translating functional into structural changes are still largely unknown. In this context, neurotrophins, like Brain-Derived Neurotrophic Factor (BDNF, are among promising candidates. Specifically BDNF-TrkB receptor signaling is crucial for activity-dependent strengthening of synapses in different brain regions. BDNF application has been shown to positively modulate dendritic and spine architecture in cortical and hippocampal neurons as well as structural plasticity in vitro. However, a global BDNF deprivation throughout the central nervous system (CNS resulted in very mild structural alterations of dendritic spines, questioning the relevance of the endogenous BDNF signaling in modulating the development and the mature structure of neurons in vivo. Here we show that a loss-of-function approach, blocking BDNF results in a significant reduction in dendritic spine density, associated with an increase in spine length and a decrease in head width. These changes are associated with a decrease in F-actin levels within spine heads. On the other hand, a gain-of-function approach, applying exogenous BDNF, could not reproduce the increase in spine density or the changes in spine morphology previously described. Taken together, we show here that the effects exerted by BDNF on the dendritic architecture of hippocampal neurons are dependent on the neuron’s maturation stage. Indeed, in mature hippocampal neurons in vitro as shown in vivo BDNF is specifically required for the activity-dependent maintenance of the mature spine phenotype.
Schmitt, Karen; Holsboer-Trachsler, Edith; Eckert, Anne
The protein brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors involved in plasticity of neurons in several brain regions. There are numerous evidence that BDNF expression is decreased by experiencing psychological stress and that, accordingly, a lack of neurotrophic support causes major depression. Furthermore, disruption in sleep homeostatic processes results in higher stress vulnerability and is often associated with stress-related mental disorders. Recently, we reported, for the first time, a relationship between BDNF and insomnia and sleep deprivation (SD). Using a biphasic stress model as explanation approach, we discuss here the hypothesis that chronic stress might induce a deregulation of the hypothalamic-pituitary-adrenal system. In the long-term it leads to sleep disturbance and depression as well as decreased BDNF levels, whereas acute stress like SD can be used as therapeutic intervention in some insomniac or depressed patients as compensatory process to normalize BDNF levels. Indeed, partial SD (PSD) induced a fast increase in BDNF serum levels within hours after PSD which is similar to effects seen after ketamine infusion, another fast-acting antidepressant intervention, while traditional antidepressants are characterized by a major delay until treatment response as well as delayed BDNF level increase. Key messages Brain-derived neurotrophic factor (BDNF) plays a key role in the pathophysiology of stress-related mood disorders. The interplay of stress and sleep impacts on BDNF level. Partial sleep deprivation (PSD) shows a fast action on BDNF level increase.
Aarabi, Mahmoud; San Gabriel, Maria C; Chan, Donovan; Behan, Nathalie A; Caron, Maxime; Pastinen, Tomi; Bourque, Guillaume; MacFarlane, Amanda J; Zini, Armand; Trasler, Jacquetta
Dietary folate is a major source of methyl groups required for DNA methylation, an epigenetic modification that is actively maintained and remodeled during spermatogenesis. While high-dose folic acid supplementation (up to 10 times the daily recommended dose) has been shown to improve sperm parameters in infertile men, the effects of supplementation on the sperm epigenome are unknown. To assess the impact of 6 months of high-dose folic acid supplementation on the sperm epigenome, we studied 30 men with idiopathic infertility. Blood folate concentrations increased significantly after supplementation with no significant improvements in sperm parameters. Methylation levels of the differentially methylated regions of several imprinted loci (H19, DLK1/GTL2, MEST, SNRPN, PLAGL1, KCNQ1OT1) were normal both before and after supplementation. Reduced representation bisulfite sequencing (RRBS) revealed a significant global loss of methylation across different regions of the sperm genome. The most marked loss of DNA methylation was found in sperm from patients homozygous for the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, a common polymorphism in a key enzyme required for folate metabolism. RRBS analysis also showed that most of the differentially methylated tiles were located in DNA repeats, low CpG-density and intergenic regions. Ingenuity Pathway Analysis revealed that methylation of promoter regions was altered in several genes involved in cancer and neurobehavioral disorders including CBFA2T3, PTPN6, COL18A1, ALDH2, UBE4B, ERBB2, GABRB3, CNTNAP4 and NIPA1. Our data reveal alterations of the human sperm epigenome associated with high-dose folic acid supplementation, effects that were exacerbated by a common polymorphism in MTHFR.
Full Text Available Abstract Background Mental deficiency has been linked to abnormalities in cortical neuronal network connectivity and plasticity. These mechanisms are in part under the control of two interacting signalling pathways, the serotonergic and the brain-derived neurotrophic (BDNF pathways. The aim of the current paper is to determine whether particular alleles or genotypes of two crucial genes of these systems, the serotonin transporter gene (SLC6A4 and the brain-derived neurotrophic factor gene (BDNF, are associated with mental deficiency (MD. Methods We analyzed four functional polymorphisms (rs25531, 5-HTTLPR, VNTR, rs3813034 of the SLC6A4 gene and one functional polymorphism (Val66 Met of the BDNF gene in 98 patients with non-syndromic mental deficiency (NS-MD and in an ethnically matched control population of 251 individuals. Results We found no significant differences in allele and genotype frequencies in the five polymorphisms studied in the SLC6A4 and BDNF genes of NS-MD patients versus control patients. While the comparison of the patterns of linkage disequilibrium (D' in the control and NS-MD populations revealed a degree of variability it did not, however, reach significance. No significant differences in frequencies of haplotypes and genotypes for VNTR/rs3813034 and rs25531/5-HTTLPR were observed. Conclusion Altogether, results from the present study do not support a role for any of the five functional polymorphisms of SLC6A4 and BDNF genes in the aetiology of NS-RM. Moreover, they suggest no epistatic interaction in NS-MD between polymorphisms in BDNF and SLC6A4. However, we suggest that further studies on these two pathways in NS-MD remain necessary.
Bennett, M R; Lagopoulos, J
Chronic restraint stress leads to increases in brain derived neurotrophic factor (BDNF) mRNA and protein in some regions of the brain, e.g. the basal lateral amygdala (BLA) but decreases in other regions such as the CA3 region of the hippocampus and dendritic spine density increases or decreases in line with these changes in BDNF. Given the powerful influence that BDNF has on dendritic spine growth, these observations suggest that the fundamental reason for the direction and extent of changes in dendritic spine density in a particular region of the brain under stress is due to the changes in BDNF there. The most likely cause of these changes is provided by the stress initiated release of steroids, which readily enter neurons and alter gene expression, for example that of BDNF. Of particular interest is how glucocorticoids and mineralocorticoids tend to have opposite effects on BDNF gene expression offering the possibility that differences in the distribution of their receptors and of their downstream effects might provide a basis for the differential transcription of the BDNF genes. Alternatively, differences in the extent of methylation and acetylation in the epigenetic control of BDNF transcription are possible in different parts of the brain following stress. Although present evidence points to changes in BDNF transcription being the major causal agent for the changes in spine density in different parts of the brain following stress, steroids have significant effects on downstream pathways from the TrkB receptor once it is acted upon by BDNF, including those that modulate the density of dendritic spines. Finally, although glucocorticoids play a canonical role in determining BDNF modulation of dendritic spines, recent studies have shown a role for corticotrophin releasing factor (CRF) in this regard. There is considerable improvement in the extent of changes in spine size and density in rodents with forebrain specific knockout of CRF receptor 1 (CRFR1) even when
Full Text Available Previous research has shown that loneliness has a heritable component and that genes within the serotonin-, dopamine-, and oxytocin systems are related to loneliness in adolescence. In the present study, the relation between the BDNF Val66Met polymorphism and loneliness in adolescent boys and girls was examined in a longitudinal study spanning five annual waves (N = 305. Latent growth curve modeling (LGCM was used to examine the baseline level and the change in loneliness over time. The main finding was that the BDNF gene was not related to loneliness in the total sample. A BDNF by sex interaction was found, in that Met carrying girls had the highest levels of loneliness at baseline, whereas in boys the ValVal genotype was related to higher levels of loneliness. Our results underline the importance of sex-stratified analyses when examining effects of the BDNF genotype and the necessity of conducting gene studies to intermediate phenotypes of loneliness.
Xu, Jie; Liu, Yun; Wang, Peng; Li, Sheng; Wang, Yabing; Li, Jun; Zhou, Daizhan; Chen, Zhuo; Zhao, Teng; Wang, Ting; Xu, He; Yang, Yifeng; Feng, Guoyin; He, Lin; Yu, Lan
Brain-derived neurotrophic factor (BDNF) is the most widely distributed neurotrophin in the central nervous system (CNS), and services many biological functions such as neural survival, differentiation, and plasticity. Previous studies have suggested that the Val66Met (also known as rs6265 or G196A) variant of BDNF is associated with bipolar disorder (BPD), but the results have been inconclusive. We therefore genotyped the Val66Met polymorphism in a Han Chinese population sample (498 cases and 501 control subjects). We found that the BDNF genotype is associated with BPD in this population (chi(2) = 9.4666, df = 2, P = 0.00884). Furthermore, our data suggested that the Met allele rather than the Val allele increased the risk for BPD in our Han population (OR = 1.44; 95% CI = 1.070-1.950; P = 0.016). Further studies are necessary to elucidate the involvement of the BDNF gene in the pathophysiology of BPD.
Neumann, Jake T; Thompson, John W; Raval, Ami P; Cohan, Charles H; Koronowski, Kevin B; Perez-Pinzon, Miguel A
Ischemic preconditioning (IPC) via protein kinase C epsilon (PKCɛ) activation induces neuroprotection against lethal ischemia. Brain-derived neurotrophic factor (BDNF) is a pro-survival signaling molecule that modulates synaptic plasticity and neurogenesis. Interestingly, BDNF mRNA expression increases after IPC. In this study, we investigated whether IPC or pharmacological preconditioning (PKCɛ activation) promoted BDNF-induced neuroprotection, if neuroprotection by IPC or PKCɛ activation altered neuronal excitability, and whether these changes were BDNF-mediated. We used both in vitro (hippocampal organotypic cultures and cortical neuronal-glial cocultures) and in vivo (acute hippocampal slices 48 hours after preconditioning) models of IPC or PKCɛ activation. BDNF protein expression increased 24 to 48 hours after preconditioning, where inhibition of the BDNF Trk receptors abolished neuroprotection against oxygen and glucose deprivation (OGD) in vitro. In addition, there was a significant decrease in neuronal firing frequency and increase in threshold potential 48 hours after preconditioning in vivo, where this threshold modulation was dependent on BDNF activation of Trk receptors in excitatory cortical neurons. In addition, 48 hours after PKCɛ activation in vivo, the onset of anoxic depolarization during OGD was significantly delayed in hippocampal slices. Overall, these results suggest that after IPC or PKCɛ activation, there are BDNF-dependent electrophysiologic modifications that lead to neuroprotection.
Eftekhari, Sanaz; Mehrabi, Soraya; Soleimani, Mansooreh; Hassanzadeh, Gholamreza; Shahrokhi, Amene; Mostafavi, Hossein; Hayat, Parisa; Barati, Mahmood; Mehdizadeh, Hajar; Rahmanzadeh, Reza; Hadjighassem, Mahmoud Reza; Joghataei, Mohammad Taghi
Excitatory GABA actions, induced by altered expression of chloride transporters (KCC2/NKCC1), can contribute to seizure generation in temporal lobe epilepsy. In the present study, we evaluated whether BDNF administration can affect KCC2/NKCC1 expression, ictogenesis and behavioral alterations in this paradigm. Status epilepticus was induced in male rats with pilocarpine, followed by a treatment of either a single high dose or multiple injections of BDNF during the latent phase of temporal lobe epilepsy. Chloride transporters expression, spontaneous recurrent seizures, and hyperexcitability post-seizural behaviors were evaluated after treatment. NKCC1 protein expression was markedly upregulated, whereas that of KCC2 was significantly downregulated in epileptic hippocampi compared to intact controls. Application of BDNF (both single high dose and multiple injections) increased KCC2 expression in epileptic hippocampi, while NKCC1 expression was downregulated exclusively by the single high dose injection of BDNF. Development of spontaneous recurrent seizures was delayed but not prevented by the treatment, and hyperexcitability behaviors were ameliorated for a short period of time. To prevent GABA-A mediated depolarization and design appropriate treatment strategies for temporal lobe epilepsy, chloride transporters can be considered as a target. Future studies are warranted to investigate any possible therapeutic effects of BDNF via altering chloride transporters expression.
Rantamäki, Tomi; Kemppainen, Susanna; Autio, Henri; Stavén, Saara; Koivisto, Hennariikka; Kojima, Masami; Antila, Hanna; Miettinen, Pasi O; Kärkkäinen, Elisa; Karpova, Nina; Vesa, Liisa; Lindemann, Lothar; Hoener, Marius C; Tanila, Heikki; Castrén, Eero
Brain-derived neurotrophic factor (BDNF) importantly regulates learning and memory and supports the survival of injured neurons. Reduced BDNF levels have been detected in the brains of Alzheimer's disease (AD) patients but the exact role of BDNF in the pathophysiology of the disorder remains obscure. We have recently shown that reduced signaling of BDNF receptor TrkB aggravates memory impairment in APPswe/PS1dE9 (APdE9) mice, a model of AD. The present study examined the influence of Bdnf gene deficiency (heterozygous knockout) on spatial learning, spontaneous exploratory activity and motor coordination/balance in middle-aged male and female APdE9 mice. We also studied brain BDNF protein levels in APdE9 mice in different ages showing progressive amyloid pathology. Both APdE9 and Bdnf mutations impaired spatial learning in males and showed a similar trend in females. Importantly, the effect was additive, so that double mutant mice performed the worst. However, APdE9 and Bdnf mutations influenced spontaneous locomotion in contrasting ways, such that locomotor hyperactivity observed in APdE9 mice was normalized by Bdnf deficiency. Obesity associated with Bdnf deficiency did not account for the reduced hyperactivity in double mutant mice. Bdnf deficiency did not alter amyloid plaque formation in APdE9 mice. Before plaque formation (3 months), BDNF protein levels where either reduced (female) or unaltered (male) in the APdE9 mouse cortex. Unexpectedly, this was followed by an age-dependent increase in mature BDNF protein. Bdnf mRNA and phospho-TrkB levels remained unaltered in the cortical tissue samples of middle-aged APdE9 mice. Immunohistological studies revealed increased BDNF immunoreactivity around amyloid plaques indicating that the plaques may sequester BDNF protein and prevent it from activating TrkB. If similar BDNF accumulation happens in human AD brains, it would suggest that functional BDNF levels in the AD brains are even lower than reported, which could
Full Text Available Brain-derived neurotrophic factor (BDNF importantly regulates learning and memory and supports the survival of injured neurons. Reduced BDNF levels have been detected in the brains of Alzheimer's disease (AD patients but the exact role of BDNF in the pathophysiology of the disorder remains obscure. We have recently shown that reduced signaling of BDNF receptor TrkB aggravates memory impairment in APPswe/PS1dE9 (APdE9 mice, a model of AD. The present study examined the influence of Bdnf gene deficiency (heterozygous knockout on spatial learning, spontaneous exploratory activity and motor coordination/balance in middle-aged male and female APdE9 mice. We also studied brain BDNF protein levels in APdE9 mice in different ages showing progressive amyloid pathology. Both APdE9 and Bdnf mutations impaired spatial learning in males and showed a similar trend in females. Importantly, the effect was additive, so that double mutant mice performed the worst. However, APdE9 and Bdnf mutations influenced spontaneous locomotion in contrasting ways, such that locomotor hyperactivity observed in APdE9 mice was normalized by Bdnf deficiency. Obesity associated with Bdnf deficiency did not account for the reduced hyperactivity in double mutant mice. Bdnf deficiency did not alter amyloid plaque formation in APdE9 mice. Before plaque formation (3 months, BDNF protein levels where either reduced (female or unaltered (male in the APdE9 mouse cortex. Unexpectedly, this was followed by an age-dependent increase in mature BDNF protein. Bdnf mRNA and phospho-TrkB levels remained unaltered in the cortical tissue samples of middle-aged APdE9 mice. Immunohistological studies revealed increased BDNF immunoreactivity around amyloid plaques indicating that the plaques may sequester BDNF protein and prevent it from activating TrkB. If similar BDNF accumulation happens in human AD brains, it would suggest that functional BDNF levels in the AD brains are even lower than reported
王建明; 胡海涛; 马东亮; 孙乃学; 赵世平; 冯海晓
Objective To investigate the distribution of brain-derived neurotrophic factor(BDNF) protein in the rabbit retina. Methods Immune response material in the retina was observed using BDNF antibody by the method of immunohistochemistry. Results BDNF gene expression was mainly found in the RGCs, also in innernuclei cells and outernuclei cells in rabbit retina. Conclusion RGC is not only the target cell of BDNF, but also express the BDNF protein. BDNF from multi-sources participates in the regulation of RGCs.
Domenico F Galati
Full Text Available Abstract Brain-derived neurotrophic factor (BDNF regulates both action potential (AP generation and neuron morphology. However, whether BDNF-induced changes in neuron morphology directly impact AP generation is unclear. We quantified BDNF’s effect on cultured cortical neuron morphological parameters and found that BDNF stimulates dendrite growth and addition of dendrites while increasing both excitatory and inhibitory presynaptic inputs in a spatially restricted manner. To gain insight into how these combined changes in neuron structure and synaptic input impact AP generation, we used the morphological parameters we gathered to generate computational models. Simulations suggest that BDNF-induced neuron morphologies generate more APs under a wide variety of conditions. Synapse and dendrite addition have the greatest impact on AP generation. However, subtle alterations in excitatory/inhibitory synapse ratio and strength have a significant impact on AP generation when synaptic activity is low. Consistent with these simulations, BDNF rapidly enhances spontaneous activity in cortical cultures. We propose that BDNF promotes neuron morphologies that are intrinsically more efficient at translating barrages of synaptic activity into APs, which is a previously unexplored aspect of BDNF’s function.
Dalle Molle, R; Portella, A K; Goldani, M Z; Kapczinski, F P; Leistner-Segal, S; Leistner-Segala, S; Salum, G A; Manfro, G G; Silveira, P P
Adverse early-life environment is associated with anxiety-like behaviors and disorders. Brain-derived neurotrophic factor (BDNF) is sensitive to this environment and could be a marker of underlying brain changes. We aimed at evaluating the development of anxiety-like behaviors in a rat model of early adversity, as well as the possible association with BDNF levels. Similar associations were investigated in a sample of adolescent humans. For the rat study, Wistar rat litters were divided into: early-life stress (ELS, limited access to nesting material) and control groups. Maternal behavior was observed from days 1 to 9 of life and, as adults, rats were subjected to behavioral testing and BDNF measurements in plasma, hippocampus, amygdala and periaqueductal gray. For the human study, 129 adolescents were evaluated for anxiety symptoms and perceived parental care. Serum BDNF levels and the Val66Met polymorphism of the BDNF gene were investigated. We found that ELS dams showed more pure contact, that is, contact with low care and high control, toward pups, and their adult offspring demonstrated higher anxiety-like behaviors and plasma BDNF. Also the pure contact correlated positively with adult peripheral BDNF. Similarly in humans, there was a positive correlation between maternal overprotection and serum BDNF only in Met carriers. We also found negative correlations between maternal warmth and separation anxiety, social phobia and school phobia. Finally, our translational approach revealed that ELS, mediated through variations in maternal care, is associated with anxiety in both rats and humans and increased peripheral BDNF may be marking these phenomena.
Yang, Bangkun; Yang, Chun; Ren, Qian; Zhang, Ji-Chun; Chen, Qian-Xue; Shirayama, Yukihiko; Hashimoto, Kenji
Using learned helplessness (LH) model of depression, we measured protein expression of brain-derived neurotrophic factor (BDNF) pro-peptide, BDNF precursors (proBDNF and preproBDNF) in the brain regions of LH (susceptible) and non-LH rats (resilience). Expression of preproBDNF, proBDNF and BDNF pro-peptide in the medial prefrontal cortex of LH rats, but not non-LH rats, was significantly higher than control rats, although expression of these proteins in the nucleus accumbens of LH rats was significantly lower than control rats. This study suggests that regional differences in conversion of BDNF precursors into BDNF and BDNF pro-peptide by proteolytic cleavage may contribute to stress resilience.
Aller, R; De Luis, D A; Fernandez, L; Calle, F; Velayos, B; Izaola, O; Gonzalez Sagrado, M; Conde, R; Gonzalez, J M
A transition G to A at codon 54 of fatty acid binding protein type 2 (FABP2) produces an amino acid substitution (Ala 54 to Thr 54). This amino acid substitution was associated with modifications of insulin resistance, adipokines and insulin concentrations. The aim of this study was to evaluate the influence of Ala54Thr polymorphism in the FABP2 gene on the histological alterations of non-alcoholic fatty liver disease (NAFLD) and insulin resistance. Thirty subjects with the presence of biopsy-proven NAFLD were enrolled for this study. Glucose, Insulin, Insulin resistance (HOMA), total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, resistin, leptin, adiponectin, interleukin-6 and TNF-alfa serum levels were measured at basal time. A tetrapolar bioimpedance, BMI, waist circumference, waist to hip ratio, blood pressure and a prospective serial assessment of nutritional intake with 3 days written food records were examined. Genotype of Ala54Thr FABP2 gene polymorphism was studied. The mean age was 41.6 +/- 11 years and the mean BMI 29.2 +/- 6.6 with 24 males (80%) and 6 females (20%). Fifteen patients (50%) had the genotype Ala54/Ala54 (wild type group) and 15 (50%) patients Ala54/Thr54 (13 patients) or Thr54/Thr54 (2 patients) (mutant type group). Both genotype groups have the similar anthropometric parameters. Serum aspartate aminotransferase and alcaline phosfatase were higher in wild type group than mutant type group, with an unclear explanation. Dietary intake was similar in both groups. A non-statistical significant low levels of adiponectin in mutant group was observed. No differences were detected among other adipokines. There were no differences between genotypes in histological results of inflammation (portal or lobular inflammation) or grade of steatosis or fibrosis. In conclusion, the present study demonstrates that the polymorphism Ala54Thr of FABP in patients with NAFLD doesn't predict liver histological changes, nor both insulin resistance
Antonio Di Lieto; Tomi Rantamäki; Liisa Vesa; Sudhirkumar Yanpallewar; Hanna Antila; Jesse Lindholm; Maribel Rios; Lino Tessarollo; Eero Castrén
BACKGROUND: Previous studies suggest that the responsiveness of TrkB receptor to BDNF is developmentally regulated in rats. Antidepressant drugs (AD) have been shown to increase TrkB signalling in the adult rodent brain, and recent findings implicate a BDNF-independent mechanism behind this phenomenon. When administered during early postnatal life, ADs produce long-lasting biochemical and behavioural alterations that are observed in adult animals. METHODOLOGY: We have here examined the respon...
Jovel, Irina Tatiana; Kofoed, Poul-Erik; Rombo, Lars;
BACKGROUND: Guinea-Bissau, West-Africa introduced artemether-lumefantrine in 2008 but quinine has also been commonly prescribed for treatment of uncomplicated Plasmodium falciparum malaria. An efficacious high-dose chloroquine treatment regimen was used previously. Temporal and seasonal changes...... of genetic polymorphisms associated with altered drug susceptibility to chloroquine, lumefantrine and quinine are described. METHODS: Pfcrt K76T, pfmdr1 gene copy numbers, N86Y, Y184F and 1034-1246 sequences were determined using PCR-based methods. Blood samples came from virtually all (n=1806) children aged.......001). CONCLUSIONS: Following the discontinuation of an effective chloroquine regimen highly artemether-lumefantrine susceptible P. falciparum (with pfcrt 76T) accumulated possibly due to suboptimal use of quinine and despite a fitness cost linked to 76T....
Chakraborty, Goutam; Magagna-Poveda, Alejandra; Parratt, Carolyn; Umans, Jason G; MacLusky, Neil J; Scharfman, Helen E
Thyroid hormone is critical for central nervous system development. Fetal hypothyroidism leads to reduced cognitive performance in offspring as well as other effects on neural development in both humans and experimental animals. The nature of these impairments suggests that thyroid hormone may exert its effects via dysregulation of the neurotrophin brain-derived neurotrophic factor (BDNF), which is critical to normal development of the central nervous system and has been implicated in neurodevelopmental disorders. The only evidence of BDNF dysregulation in early development, however, comes from experimental models in which severe prenatal hypothyroidism occurred. By contrast, milder prenatal hypothyroidism has been shown to alter BDNF levels and BDNF-dependent functions only much later in life. We hypothesized that mild experimental prenatal hypothyroidism might lead to dysregulation of BDNF in the early postnatal period. BDNF levels were measured by ELISA at 3 or 7 d after birth in different regions of the brains of rats exposed to propylthiouracil (PTU) in the drinking water. The dose of PTU that was used induced mild maternal thyroid hormone insufficiency. Pups, but not the parents, exhibited alterations in tissue BDNF levels. Hippocampal BDNF levels were reduced at both d 3 and 7, but no significant reductions were observed in either the cerebellum or brain stem. Unexpectedly, more males than females were born to PTU-treated dams, suggesting an effect of PTU on sex determination. These results support the hypothesis that reduced hippocampal BDNF levels during early development may contribute to the adverse neurodevelopmental effects of mild thyroid hormone insufficiency during pregnancy.
Full Text Available The striatum, a major component of the basal ganglia, performs multiple functions including control of movement, reward, and addiction. Dysfunction and death of striatal neurons are the main causes for the motor disorders associated with Huntington’s disease (HD. Brain-derived neurotrophic factor (BDNF, a member of the neurotrophin family, is among factors that promote survival and proper function of this neuronal population. Here, we review recent studies showing that BDNF determines the size of the striatum by supporting survival of the immature striatal neurons at their origin, promotes maturation of striatal neurons, and facilitates establishment of striatal connections during brain development. We also examine the role of BDNF in maintaining proper function of the striatum during adulthood, summarize the mechanisms that lead to a deficiency in BDNF signaling and subsequently striatal degeneration in HD, and highlight a potential role of BDNF as a therapeutic target for HD treatment.
Full Text Available Increasing evidence demonstrates a connection between growth factor function (including brain-derived neurotrophic factor, BDNF, glucocorticoid levels (one of the steroid hormones, and the pathophysiology of depressive disorders. Because both BDNF and glucocorticoids regulate synaptic function in the central nervous system, their functional interaction is of major concern. Interestingly, alterations in levels of estrogen, another steroid hormone, may play a role in depressive-like behavior in postpartum females with fluctuations of BDNF-related molecules in the brain. BDNF and cytokines, which are protein regulators of inflammation, stimulate multiple intracellular signaling cascades involved in neuropsychiatric illness. Pro-inflammatory cytokines may increase vulnerability to depressive symptoms, such as the increased risk observed in patients with cancer and/or autoimmune diseases. In this review, we discuss the possible relationship between inflammation and depression, in addition to the crosstalk among cytokines, BDNF and steroids. Further, since nutritional status has been shown to affect critical pathways involved in depression through both BDNF function and the monoamine system, we also review current evidence surrounding diet and supplementation (e.g., flavonoids on BDNF-mediated brain functions.
Kenter Gemma G
Full Text Available Abstract Background Cervical carcinoma develops as a result of multiple genetic alterations. Different studies investigated genomic alterations in cervical cancer mainly by means of metaphase comparative genomic hybridization (mCGH and microsatellite marker analysis for the detection of loss of heterozygosity (LOH. Currently, high throughput methods such as array comparative genomic hybridization (array CGH, single nucleotide polymorphism array (SNP array and gene expression arrays are available to study genome-wide alterations. Integration of these 3 platforms allows detection of genomic alterations at high resolution and investigation of an association between copy number changes and expression. Results Genome-wide copy number and genotype analysis of 10 cervical cancer cell lines by array CGH and SNP array showed highly complex large-scale alterations. A comparison between array CGH and SNP array revealed that the overall concordance in detection of the same areas with copy number alterations (CNA was above 90%. The use of SNP arrays demonstrated that about 75% of LOH events would not have been found by methods which screen for copy number changes, such as array CGH, since these were LOH events without CNA. Regions frequently targeted by CNA, as determined by array CGH, such as amplification of 5p and 20q, and loss of 8p were confirmed by fluorescent in situ hybridization (FISH. Genome-wide, we did not find a correlation between copy-number and gene expression. At chromosome arm 5p however, 22% of the genes were significantly upregulated in cell lines with amplifications as compared to cell lines without amplifications, as measured by gene expression arrays. For 3 genes, SKP2, ANKH and TRIO, expression differences were confirmed by quantitative real-time PCR (qRT-PCR. Conclusion This study showed that copy number data retrieved from either array CGH or SNP array are comparable and that the integration of genome-wide LOH, copy number and gene
Objective To investigate the relationship between the brain-derived neurotrophic factor (BDNF) gene Tag SNPs(rs 11030101 and rs6265) and early-onset schizophrenia in the Chinese Han population. Methods The tag single nucleotide polymorphisms (tag SNPs) rs11030101 and rs6265 in the BDNF gene were genotyped
Duka, Theodora; Nikolaou, Kyriaki; King, Sarah L.; Banaschewski, Tobias; Bokde, Arun L. W.; Büchel, Christian; Carvalho, Fabiana M.; Conrod, Patricia J.; Flor, Herta; Gallinat, Jürgen; Garavan, Hugh; Heinz, Andreas; Jia, Tianye; Gowland, Penny; Martinot, Jean-Luc; Paus, Tomáš; Rietschel, Marcella; Robbins, Trevor W.; Smolka, Michael; Schumann, Gunter; Stephens, David N.
Variations in genes encoding several GABAA receptors have been associated with human drug and alcohol abuse. Among these, a number of human studies have suggested an association between GABRB1, the gene encoding GABAA receptor β1 subunits, with Alcohol dependence (AD), both on its own and comorbid with other substance dependence and psychiatric illnesses. In the present study, we hypothesized that the GABRB1 genetically-associated increased risk for developing alcoholism may be associated with impaired behavioral control and altered sensitivity to reward, as a consequence of altered brain function. Exploiting the IMAGEN database (Schumann et al., 2010), we explored in a human adolescent population whether possession of the minor (T) variant of the single nucleotide polymorphism (SNP) rs2044081 is associated with performance of tasks measuring aspects of impulsivity, and reward sensitivity that are implicated in drug and alcohol abuse. Allelic variation did not associate with altered performance in either a stop-signal task (SST), measuring one aspect of impulsivity, or a monetary incentive delay (MID) task assessing reward anticipation. However, increased functional magnetic resonance imaging (fMRI) blood-oxygen-level dependent (BOLD) response in the right hemisphere inferior frontal gyrus (IFG), left hemisphere caudate/insula and left hemisphere inferior temporal gyrus (ITG) during MID performance was higher in the minor (T) allelic group. In contrast, during SST performance, the BOLD response found in the right hemisphere supramarginal gyrus, right hemisphere lingual and left hemisphere inferior parietal gyrus indicated reduced responses in the minor genotype. We suggest that β1-containing GABAA receptors may play a role in excitability of brain regions important in controlling reward-related behavior, which may contribute to susceptibility to addictive behavior. PMID:28261068
Dulka, Brooke N.; Ford, Ellen C.; Lee, Melissa A.; Donnell, Nathaniel J.; Goode, Travis D.; Prosser, Rebecca; Cooper, Matthew A.
Brain-derived neurotrophic factor (BDNF) is essential for memory processes. The present study tested whether proteolytic cleavage of proBDNF into mature BDNF (mBDNF) within the basolateral amygdala (BLA) regulates the consolidation of defeat-related memories. We found that acute social defeat increases the expression of mBDNF, but not proBDNF, in…
Wu, Y W C; Du, X; van den Buuse, M; Hill, R A
The recent use of estrogen-based therapies as adjunctive treatments for the cognitive impairments of schizophrenia has produced promising results; however the mechanism behind estrogen-based cognitive enhancement is relatively unknown. Brain-derived neurotrophic factor (BDNF) regulates learning and memory and its expression is highly responsive to estradiol. We recently found that estradiol modulates the expression of hippocampal parvalbumin-positive GABAergic interneurons, known to regulate neuronal synchrony and cognitive function. What is unknown is whether disruptions to the aforementioned estradiol-parvalbumin pathway alter learning and memory, and whether BDNF may mediate these events. Wild-type (WT) and BDNF heterozygous (+/-) mice were ovariectomized (OVX) at 5 weeks of age and simultaneously received empty, estradiol- or progesterone-filled implants for 7 weeks. At young adulthood, mice were tested for spatial and recognition memory in the Y-maze and novel-object recognition test, respectively. Hippocampal protein expression of BDNF and GABAergic interneuron markers, including parvalbumin, were assessed. WT OVX mice show impaired performance on Y-maze and novel-object recognition test. Estradiol replacement in OVX mice prevented the Y-maze impairment, a Behavioral abnormality of dorsal hippocampal origin. BDNF and parvalbumin protein expression in the dorsal hippocampus and parvalbumin-positive cell number in the dorsal CA1 were significantly reduced by OVX in WT mice, while E2 replacement prevented these deficits. In contrast, BDNF(+/-) mice showed either no response or an opposite response to hormone manipulation in both behavioral and molecular indices. Our data suggest that BDNF status is an important biomarker for predicting responsiveness to estrogenic compounds which have emerged as promising adjunctive therapeutics for schizophrenia patients.
Ban, Ju Yeon; Kang, Soon Ah; Jung, Kyung Hee; Kim, Hak Jae; Uhm, Yoon Kyung; Kim, Su Kang; Yim, Sung-Vin; Choe, Bong-Keun; Hong, Seung-Jae; Seong, Yeon Hee; Koh, In Song; Chung, Joo-Ho
Pre-B-cell leukemia transcription factor 1 (PBX1), which is located on chromosome 1q23, was recently reported to be associated with type 2 diabetes mellitus. We examined whether single nucleotide polymorphisms (SNPs) of the PBX1 gene are associated with overweight/obesity in a Korean population. We genotyped 66 SNPs in the PBX1 gene and investigated their association with clinical phenotypes found in 214 overweight/obese subjects and 160 control subjects using the Affymetrix Targeted Genotyping chip array. Seven SNPs (g.+75186C>T, g.+78350C>A, g.+80646C>T, g.+138004C>T, g.+185219G>A, g.+191272A>C, and g.+265317T>A) were associated with the risk of obesity in three models (codominant, dominant, and recessive) (P=0.007-0.05). Haplotype 1 (CAC) and 3 (TAC) of block 3 and haplotype 2 (GGAAT) of block 10 were also strongly associated with the risk of obesity. In the control group, subjects that had homozygote for the major allele for both g.+185219G>A and g.+191272A>C showed lower high density lipoprotein-cholesterol (HDL-C) level compared to those possessing the minor allele, suggesting that the association between the homozygote for the major allele for both g.+185219G>A and g.+191272A>C and HDL-C is attributable to the increased risk of obesity. This study suggests that the PBX1 gene is a possible risk factor in overweight/obese patients.
Stadelmann, Andreas M; Juckel, Georg; Arning, Larissa; Gallinat, Jürgen; Epplen, Jörg T; Roser, Patrik
Numerous studies demonstrated a close relationship between cannabis abuse and schizophrenia with similar impairments in cognitive processing, particularly in P300 generation. Recently, an (AAT)n triplet repeat polymorphism within the cannabinoid receptor gene CNR1 has been found to be associated with both schizophrenia and substance dependence, and to modulate the P300 potential. As previously reported, both acute oral Δ(9)-tetrahydrocannabinol (Δ(9)-THC), the main psychoactive constituent of cannabis, and standardized cannabis extract containing Δ(9)-THC and cannabidiol (CBD) revealed a significant reduction of P300 amplitudes in healthy subjects but did not show any differences among each other. The aim of this study was to investigate whether the (AAT)n polymorphism differentially modulates the effects of Δ(9)-THC and cannabis extract on P300 generation in 20 healthy volunteers during an auditory choice reaction task. For the >10/>10 genotype, there was a significant decrease of P300 amplitude as well as a significant prolongation of P300 latency under pure Δ(9)-THC but not under cannabis extract. Moreover, we found a significant correlation between the number of AAT repeats and P300 variables for the Δ(9)-THC condition. Our data thus indicate that the CNR1 gene seems to be involved in the regulation of the P300 wave as a marker of selective attention and working memory. Moreover, it appears that variations within CNR1 may differentially alter the sensitivity to the acute effects of cannabinoids on P300 generation in healthy subjects.
Koshimizu Hisatsugu; Kiyosue Kazuyuki; Hara Tomoko; Hazama Shunsuke; Suzuki Shingo; Uegaki Koichi; Nagappan Guhan; Zaitsev Eugene; Hirokawa Takatsugu; Tatsu Yoshiro; Ogura Akihiko; Lu Bai; Kojima Masami
Abstract Background Proneurotrophins and mature neurotrophins elicit opposite effects via the p75 neurotrophin receptor (p75NTR) and Trk tyrosine kinase receptors, respectively; however the molecular roles of proneurotrophins in the CNS are not fully understood. Results Based on two rare single nucleotide polymorphisms (SNPs) of the human brain-derived neurotrophic factor (BDNF) gene, we generated R125M-, R127L- and R125M/R127L-BDNF, which have amino acid substitution(s) near the cleavage sit...
Santacana, Martí; Arias, Bárbara; Mitjans, Marina; Bonillo, Albert; Montoro, María; Rosado, Sílvia; Guillamat, Roser; Vallès, Vicenç; Pérez, Víctor; Forero, Carlos G.; Fullana, Miquel A.
Background Anxiety disorders are highly prevalent and result in low quality of life and a high social and economic cost. The efficacy of cognitive-behavioural therapy (CBT) for anxiety disorders is well established, but a substantial proportion of patients do not respond to this treatment. Understanding which genetic and environmental factors are responsible for this differential response to treatment is a key step towards “personalized medicine”. Based on previous research, our objective was to test whether the BDNF Val66Met polymorphism and/or childhood maltreatment are associated with response trajectories during exposure-based CBT for panic disorder (PD). Method We used Growth Mixture Modeling to identify latent classes of change (response trajectories) in patients with PD (N = 97) who underwent group manualized exposure-based CBT. We conducted logistic regression to investigate the effect on these trajectories of the BDNF Val66Met polymorphism and two different types of childhood maltreatment, abuse and neglect. Results We identified two response trajectories (“high response” and “low response”), and found that they were not significantly associated with either the genetic (BDNF Val66Met polymorphism) or childhood trauma-related variables of interest, nor with an interaction between these variables. Conclusions We found no evidence to support an effect of the BDNF gene or childhood trauma-related variables on CBT outcome in PD. Future studies in this field may benefit from looking at other genotypes or using different (e.g. whole-genome) approaches. PMID:27355213
Full Text Available Anxiety disorders are highly prevalent and result in low quality of life and a high social and economic cost. The efficacy of cognitive-behavioural therapy (CBT for anxiety disorders is well established, but a substantial proportion of patients do not respond to this treatment. Understanding which genetic and environmental factors are responsible for this differential response to treatment is a key step towards "personalized medicine". Based on previous research, our objective was to test whether the BDNF Val66Met polymorphism and/or childhood maltreatment are associated with response trajectories during exposure-based CBT for panic disorder (PD.We used Growth Mixture Modeling to identify latent classes of change (response trajectories in patients with PD (N = 97 who underwent group manualized exposure-based CBT. We conducted logistic regression to investigate the effect on these trajectories of the BDNF Val66Met polymorphism and two different types of childhood maltreatment, abuse and neglect.We identified two response trajectories ("high response" and "low response", and found that they were not significantly associated with either the genetic (BDNF Val66Met polymorphism or childhood trauma-related variables of interest, nor with an interaction between these variables.We found no evidence to support an effect of the BDNF gene or childhood trauma-related variables on CBT outcome in PD. Future studies in this field may benefit from looking at other genotypes or using different (e.g. whole-genome approaches.
Full Text Available Neonatal blockade of N-methyl-D-aspartic acid (NMDA receptors represents one of experimental animal models for schizophrenia. This study is to investigate the long-term brain-derived neurotrophic factor (BDNF expression profiles in different regions and correlation with “schizophrenia-like” behaviors in the adolescence and adult of this rat model. The NMDA receptor antagonist MK801 was administered to female Sprague-Dawley rats on postnatal days (PND 5 through 14. Open-field test was performed on PND 42, and PND 77 to examine the validity of the current model. BDNF protein levels in hippocampus and prefrontal cortex (PFC were analyzed on PND 15, PND 42, and PND 77. Results showed that neonatal challenge with MK-801 persistently elevated locomotor activity as well as BDNF expression; the alterations in BDNF expression varied at different developing stages and among brain regions. However, these findings provide neurochemical evidence that the blockade of NMDA receptors during brain development results in long-lasting alterations in BDNF expression and might contribute to neurobehavioral pathology of the present animal model for schizophrenia. Further study in the mechanisms and roles of the BDNF may lead to better understanding of the pathophysiology of schizophrenia.
Klein, Anders B; Jennum, Poul; Knudsen, Stine
in hypocretin neurons in hypothalamus in post-mortem tissue. Brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are important for activity-dependent neuronal function and synaptic modulation and it is considered that these mechanisms are important in sleep regulation. We hypothesised......Narcolepsy is a lifelong sleep disorder characterized by excessive daytime sleepiness, sudden loss of muscle tone (cataplexy), fragmentation of nocturnal sleep and sleep paralysis. The symptoms of the disease strongly correlate with a reduction in hypocretin levels in CSF and a reduction...... that serum levels of these factors are altered in patients with narcolepsy compared to healthy controls without sleep disturbances. Polysomnography data was obtained and serum BDNF and NGF levels measured using ELISA, while hypocretin was measured using RIA. Serum BDNF levels were significantly higher...
Luciano K. Jornada
Full Text Available OBJECTIVE: The present study aims to investigate the effects of ouabain intracerebroventricular injection on BDNF levels in the amygdala and hippocampus of Wistar rats. METHODS: Animals received a single intracerebroventricular injection of ouabain (10-3 and 10-2 M or artificial cerebrospinal fluid and immediately, 1h, 24h, or seven days after injection, BDNF levels were measured in the rat's amygdala and hippocampus by sandwich-ELISA (n = 8 animals per group. RESULTS: When evaluated immediately, 3h, or 24h after injection, ouabain in doses of 10-2 and 10-3 M does not alter BDNF levels in the amygdala and hippocampus. However, when evaluated seven days after injection, ouabain in 10-2 and 10-3 M, showed a significant reduction in BDNF levels in both brain regions evaluated. DISCUSSION: In conclusion, we propose that the ouabain decreased BDNF levels in the hippocampus and amygdala when assessed seven days after administration, supporting the Na/K ATPase hypothesis for bipolar illness.
McDole, B; Isgor, C; Pare, C; Guthrie, K
Olfactory bulb granule cells (GCs) are axon-less, inhibitory interneurons that regulate the activity of the excitatory output neurons, the mitral and tufted cells, through reciprocal dendrodendritic synapses located on GC spines. These contacts are established in the distal apical dendritic compartment, while GC basal dendrites and more proximal apical segments bear spines that receive glutamatergic inputs from the olfactory cortices. This synaptic connectivity is vital to olfactory circuit function and is remodeled during development, and in response to changes in sensory activity and lifelong GC neurogenesis. Manipulations that alter levels of the neurotrophin brain-derived neurotrophic factor (BDNF) in vivo have significant effects on dendritic spine morphology, maintenance and activity-dependent plasticity for a variety of CNS neurons, yet little is known regarding BDNF effects on bulb GC spine maturation or maintenance. Here we show that, in vivo, sustained bulbar over-expression of BDNF in transgenic mice produces a marked increase in GC spine density that includes an increase in mature spines on their apical dendrites. Morphometric analysis demonstrated that changes in spine density were most notable in the distal and proximal apical domains, indicating that multiple excitatory inputs are potentially modified by BDNF. Our results indicate that increased levels of endogenous BDNF can promote the maturation and/or maintenance of dendritic spines on GCs, suggesting a role for this factor in modulating GC functional connectivity within adult olfactory circuitry.
Ilchibaeva, Tatiana V; Kondaurova, Elena M; Tsybko, Anton S; Kozhemyakina, Rimma V; Popova, Nina K; Naumenko, Vladimir S
The brain-derived neurotrophic factor (BDNF), its precursor (proBDNF) and BDNF mRNA levels were studied in the brain of wild rats selectively bred for more than 70 generations for either high level or for the lack of affective aggressiveness towards man. Significant increase of BDNF mRNA level in the frontal cortex and increase of BDNF level in the hippocampus of aggressive rats was revealed. In the midbrain and hippocampus of aggressive rats proBDNF level was increased, whereas BDNF/proBDNF ratio was reduced suggesting the prevalence and increased influence of proBDNF in highly aggressive rats. In the frontal cortex, proBDNF level in aggressive rats was decreased. Thus, considerable structure-specific differences in BDNF and proBDNF levels as well as in BDNF gene expression between highly aggressive and nonaggressive rats were shown. The data suggested the implication of BDNF and its precursor proBDNF in the mechanism of aggressiveness and in the creation of either aggressive or nonaggressive phenotype.
Tran, Phu V; Kennedy, Bruce C; Lien, Yu-Chin; Simmons, Rebecca A; Georgieff, Michael K
Fetal and subsequent early postnatal iron deficiency causes persistent impairments in cognitive and affective behaviors despite prompt postnatal iron repletion. The long-term cognitive impacts are accompanied by persistent downregulation of brain-derived neurotrophic factor (BDNF), a factor critical for hippocampal plasticity across the life span. This study determined whether early-life iron deficiency epigenetically modifies the Bdnf locus and whether dietary choline supplementation during late gestation reverses these modifications. DNA methylation and histone modifications were assessed at the Bdnf-IV promoter in the hippocampus of rats [at postnatal day (PND) 65] that were iron-deficient (ID) during the fetal-neonatal period. Iron deficiency was induced in rat pups by providing pregnant and nursing dams an ID diet (4 mg/kg Fe) from gestational day (G) 2 through PND7, after which iron deficiency was treated with an iron-sufficient (IS) diet (200 mg/kg Fe). This paradigm resulted in about 60% hippocampal iron loss on PND15 with complete recovery by PND65. For choline supplementation, pregnant rat dams were given dietary choline (5 g/kg) from G11 through G18. DNA methylation was determined by quantitative sequencing of bisulfite-treated DNA, revealing a small alteration at the Bdnf-IV promoter. Chromatin immunoprecipitation analysis showed increased HDAC1 binding accompanied by reduced binding of RNA polymerase II and USF1 at the Bdnf-IV promoter in formerly ID rats. These changes were correlated with altered histone methylations. Prenatal choline supplementation reverses these epigenetic modifications. Collectively, the findings identify epigenetic modifications as a potential mechanism to explicate the long-term repression of Bdnf following fetal and early postnatal iron deficiency.
Full Text Available AIMS/HYPOTHESIS: Polymorphisms in the transcription factor 7-like 2 (TCF7L2 gene have been shown to display a powerful association with type 2 diabetes. The aim of the present study was to evaluate metabolic alterations in carriers of a common TCF7L2 risk variant. METHODS: Seventeen non-diabetic subjects carrying the T risk allele at the rs7903146 TCF7L2 locus and 24 subjects carrying no risk allele were submitted to intravenous glucose tolerance test and euglycemic-hyperinsulinemic clamp. Plasma samples were analysed for concentrations of 163 metabolites through targeted mass spectrometry. RESULTS: TCF7L2 risk allele carriers had a reduced first-phase insulin response and normal insulin sensitivity. Under fasting conditions, carriers of TCF7L2 rs7903146 exhibited a non-significant increase of plasma sphingomyelins (SMs, phosphatidylcholines (PCs and lysophosphatidylcholines (lysoPCs species. A significant genotype effect was detected in response to challenge tests in 6 SMs (C16:0, C16:1, C18:0, C18:1, C24:0, C24:1, 5 hydroxy-SMs (C14:1, C16:1, C22:1, C22:2, C24:1, 4 lysoPCs (C14:0, C16:0, C16:1, C17:0, 3 diacyl-PCs (C28:1, C36:6, C40:4 and 4 long-chain acyl-alkyl-PCs (C40:2, C40:5, C44:5, C44:6. DISCUSSION: Plasma metabolomic profiling identified alterations of phospholipid metabolism in response to challenge tests in subjects with TCF7L2 rs7903146 genotype. This may reflect a genotype-mediated link to early metabolic abnormalities prior to the development of disturbed glucose tolerance.
Wen-Dong You; Qi-Lin Tang; Lei Wang; Jin Lei; Jun-Feng Feng; Qing Mao; Guo-Yi Gao
Purpose:It is becoming increasingly clear that genetic factors play a role in traumatic brain injury (TBI),whether in modifying clinical outcome after TBI or determining susceptibility to it.MicroRNAs are small RNA molecules involved in various pathophysiological processes by repressing target genes at the posttranscriptional level,and TBI alters microRNA expression levels in the hippocampus and cortex.This study was designed to detect differentially expressed microRNAs in the cerebrospinal fluid (CSF) of TBI patients remaining unconscious two weeks after initial injury and to explore related single nucleotide polymorphisms (SNPs).Methods:We used a microarray platform to detect differential microRNA expression levels in CSF samples from patients with post-traumatic coma compared with samples from controls.A bioinformatic scan was performed covering microRNA gene promoter regions to identify potential functional SNPs.Results:Totally 26 coma patients and 21 controls were included in this study,with similar distribution of age and gender between the two groups.Microarray showed that fourteen microRNAs were differentially expressed,ten at higher and four at lower expression levels in CSF of traumatic coma patients compared with controls (p ＜ 0.05).One SNP (rs11851174 allele:C/T) was identified in the motif area of the microRNA hsa-miR-431-3P gene promoter region.Conclusion:The altered microRNA expression levels in CSF after brain injury together with SNP identified within the microRNA gene promoter area provide a new perspective on the mechanism of impaired consciousness after TBI.Further studies are needed to explore the association between the specific microRNAs and their related SNPs with post-traumatic unconsciousness.
Jacobsen, Jacob P R; Mørk, Arne
This study examined the effects of chronic corticosterone (32 mg/kg/day, s.c., 21 days) on brain-derived neurotrophic factor (BDNF) mRNA and protein in the frontal cortex and hippocampus of the rat. Because evidence suggests that BDNF is an important determinant of the function of the 5-hydroxytryptamine (5-HT) system, we also quantified tissue levels of 5-HT and its major metabolite, 5-hydroxyindoleacetic acid (5-HIAA), to investigate if changes in BDNF mRNA and protein paralleled changes in the 5-HT system. Corticosterone modestly decreased BDNF protein (-16.6%) in whole hippocampus and BDNF mRNA (-19%) in the CA3 area. In contrast, BDNF mRNA and protein in the frontal cortex were unchanged. In both the frontal cortex and hippocampus, tissue levels of 5-HT and 5-HIAA were increased and decreased, respectively. Combined, these data suggests that the effects of corticosterone on the BDNF system are not linked to the effects on the 5-HT systems. However, our findings do suggest that chronic corticosterone impairs hippocampal BDNF function, a finding with potential relevance for the hippocampal atrophy reported in major depression. Additionally, as inferred from the alterations in tissue levels of 5-HT and 5-HIAA, chronic corticosterone may influence the function of the 5-HT system.
Guo, J; Ji, Y; Ding, Y; Jiang, W; Sun, Y; Lu, B; Nagappan, G
The precursor of brain-derived neurotrophic factor (BDNF) (proBDNF) is enzymatically cleaved, by either intracellular (furin/PC1) or extracellular proteases (tPA/plasmin/MMP), to generate mature BDNF (mBDNF) and its pro-peptide (BDNF pro-peptide). Little is known about the function of BDNF pro-peptide. We have developed an antibody that specifically detects cleaved BDNF pro-peptide, but not proBDNF or mBDNF. Neuronal depolarization elicited a marked increase in extracellular BDNF pro-peptide, suggesting activity-dependent regulation of its extracellular levels. Exposure of BDNF pro-peptide to mature hippocampal neurons in culture dramatically reduced dendritic spine density. This effect was mediated by caspase-3, as revealed by studies with pharmacological inhibitors and genetic knockdown. BDNF pro-peptide also increased the number of 'elongated' mitochondria and cytosolic cytochrome c, suggesting the involvement of mitochondrial-caspase-3 pathway. These results, along with BDNF pro-peptide effects recently reported on growth cones and long-term depression (LTD), suggest that BDNF pro-peptide is a negative regulator of neuronal structure and function.
Full Text Available The prevalence of penicillin non-susceptible Streptococcus pneumoniae (PNSSP is increasing among isolates from acute otitis media (AOM. Repeated episodes of antibiotic exposure are a well-known risk factor for the isolation of PNSSP although otitis-prone or recurrent AOM cases frequently require repeated courses of antibiotic treatment. In order to evaluate the chronological alteration of S. pneumoniae during recurrences of AOM, strains of S. pneumoniae were isolated from 11 patients, each of whom had experienced 2-4 episodes of AOM, were examined. Every bacterial specimen obtained from a single episode of recurrent AOM was examined by PCR-based penicillin-binding protein (PBP assay, serotyping, and amplified fragment length polymorphism (AFLP, then compared to other samples from the same case. Two cases (18.2% showed strain diversity during repeated antibiotic treatments by serotyping or PBP-assay. By AFLP analysis, 6 cases (54.5% demonstrated heterogeneous strains during recurrent AOM. Clonal survivors of previous episodes of AOM were not always the cause of subsequent episodes of AOM, even in otitis-prone cases.
Full Text Available Brain-derived neurotrophic factor (BDNF represents promotesa key molecule for the survival and differentiation of specific populations of neurons in the central nervous system. BDNF also regulates plasticity-related processes underlying memory and learning. A common single nucleotide polymorphism (SNP rs6265 has been identified on the coding sequence of human BDNF located at 11p13. The SNP rs6265 is a single base mutation with an adenine instead of a guanine at position 196 (G196A, resulting in the amino acid substitution Val66Met. This polymorphism only exists in humans and has been associated with a plethora of effects ranging from molecular, cellular and brain structural modifications in association with deficits in social and cognitive functions. To date, the literature on Val66Met polymorphism describes a complex and often conflicting pattern of effects. In this review, we attempt to provide a unifying model of the Val66Met effects. We discuss the clinical evidence of the association between Val66Met and memory deficits, as well as the molecular mechanisms involved including the reduced transport of BDNF mRNA to the dendrites as well as the reduced processing and secretion of BDNF protein through the regulated secretory pathway.
Rantamäki, Tomi; Kemppainen, Susanna; Autio, Henri; Stavén, Saara; Koivisto, Hennariikka; Kojima, Masami; Antila, Hanna; Miettinen, Pasi O.; Kärkkäinen, Elisa; Karpova, Nina; Vesa, Liisa; Lindemann, Lothar; Hoener, Marius C.; Tanila, Heikki; Castrén, Eero
Brain-derived neurotrophic factor (BDNF) importantly regulates learning and memory and supports the survival of injured neurons. Reduced BDNF levels have been detected in the brains of Alzheimer’s disease (AD) patients but the exact role of BDNF in the pathophysiology of the disorder remains obscure. We have recently shown that reduced signaling of BDNF receptor TrkB aggravates memory impairment in APPswe/PS1dE9 (APdE9) mice, a model of AD. The present study examined the influence of Bdnf gene deficiency (heterozygous knockout) on spatial learning, spontaneous exploratory activity and motor coordination/balance in middle-aged male and female APdE9 mice. We also studied brain BDNF protein levels in APdE9 mice in different ages showing progressive amyloid pathology. Both APdE9 and Bdnf mutations impaired spatial learning in males and showed a similar trend in females. Importantly, the effect was additive, so that double mutant mice performed the worst. However, APdE9 and Bdnf mutations influenced spontaneous locomotion in contrasting ways, such that locomotor hyperactivity observed in APdE9 mice was normalized by Bdnf deficiency. Obesity associated with Bdnf deficiency did not account for the reduced hyperactivity in double mutant mice. Bdnf deficiency did not alter amyloid plaque formation in APdE9 mice. Before plaque formation (3 months), BDNF protein levels where either reduced (female) or unaltered (male) in the APdE9 mouse cortex. Unexpectedly, this was followed by an age-dependent increase in mature BDNF protein. Bdnf mRNA and phospho-TrkB levels remained unaltered in the cortical tissue samples of middle-aged APdE9 mice. Immunohistological studies revealed increased BDNF immunoreactivity around amyloid plaques indicating that the plaques may sequester BDNF protein and prevent it from activating TrkB. If similar BDNF accumulation happens in human AD brains, it would suggest that functional BDNF levels in the AD brains are even lower than reported, which could
Aonurm-Helm, Anu; Anier, Kaili; Zharkovsky, Tamara; Castrén, Eero; Rantamäki, Tomi; Stepanov, Vladimir; Järv, Jaak; Zharkovsky, Alexander
Mood disorders are associated with alterations in serotonergic system, deficient BDNF (brain-derived neurotrophic factor) signaling and abnormal synaptic plasticity. Increased degradation and reduced functions of NCAM (neural cell adhesion molecule) have recently been associated with depression and NCAM deficient mice show depression-related behavior and impaired learning. The aim of the present study was to investigate potential changes in serotonergic and BDNF systems in NCAM knock-out mice. Serotonergic nerve fiber density and SERT (serotonin transporter) protein levels were robustly reduced in the hippocampus, prefrontal cortex and basolateral amygdala of adult NCAM(-)(/-) mice. This SERT reduction was already evident during early postnatal development. [(3)H]MADAM binding experiments further demonstrated reduced availability of SERT in cell membranes of NCAM(-)(/-) mice. Moreover, the levels of serotonin and its major metabolite 5-HIAA were down regulated in the brains of NCAM(-)(/-) mice. NCAM(-)(/-) mice also showed a dramatic reduction in the BDNF protein levels in the hippocampus and prefrontal cortex. This BDNF deficiency was associated with reduced phosphorylation of its receptor TrkB. Importantly, chronic administration of antidepressant amitriptyline partially or completely restored these changes in serotonergic and BDNF systems, respectively. In conclusion, NCAM deficiency lead to prominent and persistent abnormalities in brain serotonergic and BDNF systems, which likely contributes to the behavioral and neurobiological phenotype of NCAM(-/-) mice.
Wan, Lihong; Xie, Yizhou; Su, Lan; Liu, Yanyou; Wang, Yuhui; Wang, Zhengrong
Chronic morphine addiction may trigger functional changes in the mesolimbic dopamine system, which is believed to be the neurobiological substrate of opiate addiction. Brain derived neurotrophic factor (BDNF) has been implicated in addiction-related pathology in animal studies. Our previous studies have shown that RACK1 is involved in morphine reward in mice. The recent research indicates nuclear RACK1 by localizing at the promoter IV region of the BDNF gene and the subsequent chromatin modifications leads to the activation of the promoter and transcription of BDNF. The present study was designed to investigate if shRACK1 (a short hairpin RNA of RACK1) could reverse the mice's behavioral responses to morphine and BDNF expression in hippocampus and prefrontal cortex. No significant changes were observed in vehicle-infused mice which received no morphine treatment (CONC) and shRACK1-infused mice which received no morphine treatment (CONR), whereas vehicle-infused mice preceded the morphine injection (MIC) showed increased BDNF expression in hippocampus and prefrontal cortex, as compared to vehicle-infused mice which received no morphine treatment (CONC). Intracerebroventricular shRACK1 treatment reversed these, and in fact, ShRACK1-infused mice preceded the morphine injection (MIR) showed reduced BDNF expression in hippocampus and prefrontal cortex, as compared to MIC. In the conditioned place preference (CPP) test, inactivating RACK1 markedly reduces morphine-induced conditioned place preference. Non-specific changes in CPP could not account for these effects since general CPP of shRACK1- and vehicle-infused animals was not different. Combined behavioral and molecular approaches have support the possibility that the RACK1-BDNF system plays an important role in the response to morphine-induced reward.
Holm, Mai Marie; Nieto-Gonzalez, Jose Luis; Vardya, Irina; Vaegter, Christian Bjerggaard; Nykjaer, Anders; Jensen, Kimmo
Mature BDNF and its precursor proBDNF may both be secreted to exert opposite effects on synaptic plasticity in the hippocampus. However, it is unknown how proBDNF and mature BDNF affect the excitability of GABAergic interneurons and thereby regulate GABAergic inhibition. We made recordings of GABAergic spontaneous IPSCs (sIPSCs) in mouse dentate gyrus granule cells and found that chronic or acute BDNF reductions led to large increases in the sIPSC frequencies, which were TTX (tetrodotoxin) sensitive and therefore action-potential driven. Conversely, addition of mature BDNF, but not proBDNF, within minutes led to a decrease in the sIPSC frequency to 44%. Direct recordings from fast-spiking GABAergic interneurons revealed that mature BDNF reduced their excitability and depressed their action potential firing, whereas proBDNF had no effect. Using the TrkB inhibitor K-252a, or mice deficient for the common neurotrophin receptor p75(NTR), the regulation of GABAergic activity was shown specifically to be mediated by BDNF binding to the neurotrophin receptor TrkB. In agreement, immunohistochemistry demonstrated that TrkB, but not p75(NTR), was expressed in parvalbumin-positive interneurons. Our results suggest that mature BDNF decreases the excitability of GABAergic interneurons via activation of TrkB, while proBDNF does not impact on GABAergic activity. Thus, by affecting the firing of GABAergic interneurons, mature BDNF may play an important role in regulating network oscillations in the hippocampus.
Aguado, Fernando; Carmona, Maria A; Pozas, Esther; Aguiló, Agustín; Martínez-Guijarro, Francisco J; Alcantara, Soledad; Borrell, Victor; Yuste, Rafael; Ibañez, Carlos F; Soriano, Eduardo
Spontaneous neural activity is a basic property of the developing brain, which regulates key developmental processes, including migration, neural differentiation and formation and refinement of connections. The mechanisms regulating spontaneous activity are not known. By using transgenic embryos that overexpress BDNF under the control of the nestin promoter, we show here that BDNF controls the emergence and robustness of spontaneous activity in embryonic hippocampal slices. Further, BDNF dramatically increases spontaneous co-active network activity, which is believed to synchronize gene expression and synaptogenesis in vast numbers of neurons. In fact, BDNF raises the spontaneous activity of E18 hippocampal neurons to levels that are typical of postnatal slices. We also show that BDNF overexpression increases the number of synapses at much earlier stages (E18) than those reported previously. Most of these synapses were GABAergic, and GABAergic interneurons showed hypertrophy and a 3-fold increase in GAD expression. Interestingly, whereas BDNF does not alter the expression of GABA and glutamate ionotropic receptors, it does raise the expression of the recently cloned K(+)/Cl(-) KCC2 co-transporter, which is responsible for the conversion of GABA responses from depolarizing to inhibitory, through the control of the Cl(-) potential. Together, results indicate that both the presynaptic and postsynaptic machineries of GABAergic circuits may be essential targets of BDNF actions to control spontaneous activity. The data indicate that BDNF is a potent regulator of spontaneous activity and co-active networks, which is a new level of regulation of neurotrophins. Given that BDNF itself is regulated by neuronal activity, we suggest that BDNF acts as a homeostatic factor controlling the emergence, complexity and networking properties of spontaneous networks.
Full Text Available BACKGROUND: It has been confirmed that tumor necrosis factor-alpha (TNFα, a macrophage-derived pro-inflammatory cytokine, plays an important role in the pathogenesis of psoriasis vulgaris and psoriatic arthritis (PsV&PsA. In contrast, the reported association of TNFα gene promoter region single nucleotide polymorphisms (SNPs and PsV&PsA has remained controversial. Accordingly, we performed a meta-analysis to provide new evidence that SNPs in the TNFα gene promoter region alter not only the risk of psoriasis vulgaris (PsV or psoriatic arthritis (PsA but also of PsV&PsA. METHODS: Interrelated literature dated to October 2012 was acquired from the PubMed, ScienceDirect, and SpringerLink databases. The number of the genotypes and/or alleles for the TNFα promoter in the PsV and PsA and control subjects was obtained. Odds ratios (ORs and 95% confidence intervals (CIs were used to calculate the risk of PsV and/or PsA with TNFα promoter SNPs. RESULTS: A total of 26 papers of 2159 for PsV (2129 normal controls and 2360 for PsA (2997 normal controls were included in our meta-analysis. The results showed that the variant genotype and allele of TNFα -308A/G was protective in pooled groups of patients with PsV&PsA (OR = 0.682, 0.750; 95% CI, 0.596-0.779, 0.653-0.861. However, the variant genotypes and alleles of TNFα -238A/G and -857T/C had an increased risk of PsV&PsA (OR = 2.493, 2.228, 1.536, 1.486, 95% CI, 1.777-3.498, 1.628-3.049, 1.336-1.767, 1.309-1.685. Moreover, the meta-analysis revealed a significant association between TNFα -238A/G and -857T/C polymorphism and PsA susceptibility (OR = 2.242, 2.052, 1.419, 1.465; 95% CI, 1.710-2.941, 1.614-2.610, 1.214-1.658, 1.277-1.681. In contrast, the variant genotypes and alleles of TNFα -308A/G proved to be protective against PsV (OR = 0.574, 0.650, 95% CI, 0.478-0.690, 0.556-0.759, whereas TNFα -238A/G was found to have a risk association (OR = 2.636, 2.223, 95% CI, 1.523-4.561, 1
Full Text Available BACKGROUND: Current theories on the pathophysiology of schizophrenia suggest altered brain plasticity such as decreased neural proliferation and migration, delayed myelination, and abnormal synaptic modeling, in the brain of subjects with schizophrenia. Though functional alterations in BDNF, which plays important role in neuroplasticity, are implicated in many abnormalities found in schizophrenia, the regulatory mechanism(s involved in the abnormal signaling of BDNF in schizophrenia is not clear. The present study investigated whether Sprouty2, a regulator of growth factor signaling, is abnormally expressed in schizophrenia, and is associated with the changes in BDNF mRNA in this disorder. The potential effect of antipsychotic drugs on Sprouty2 expression was tested in adult rats. METHODS AND FINDINGS: Sprouty2 and BDNF gene expression were analyzed in dorsolateral prefrontal cortex samples from the Stanley Array Collection. Quantitative real-time PCR analysis of RNA in 100 individuals (35 with schizophrenia, 31 with bipolar disorder, and 34 psychiatrically normal controls showed significantly decreased expression of Sprouty2 and BDNF in both schizophrenia and bipolar disorder. Moreover, a significant correlation between these two genes existed in control, schizophrenia and bipolar subjects. Long-term treatment with antipsychotic drugs, haloperidol and olanzapine, showed differential effects on both Sprouty2 and BDNF mRNA and protein levels in the frontal cortex of rats. CONCLUSION: These findings demonstrating decreased expression of Sprouty2 associated with changes in BDNF, suggest the possibility that these decreases are secondary to treatment rather than to factors that are significant in the disease process of either schizophrenia and/or bipolar disorder. Further exploration of Sprouty2-related signal transduction pathways may be helpful to design novel treatment strategies for these disorders.
Bath, Kevin G; Akins, Michael R; Lee, Francis S
The sensory processing of odorants is a dynamic process that requires plasticity at multiple levels. In the olfactory bulb (OB), inhibitory interneurons undergo lifelong replacement through a process known as adult neurogenesis. These newly born cells are incorporated in a learning-dependent fashion, a process which has led some to suggest this as a primary mechanism through which the OB retains a high degree of plasticity throughout life. A continued focus of researchers in this field has been to understand the molecular mechanisms controlling adult subventricular zone (SVZ) neurogenesis and the innate functional role of these cells. Brain-derived neurotrophic factor (BDNF) has been identified as a strong candidate molecule regulating adult OB neurogenesis. We review what is known regarding the functional role of newly born cells, highlight the role of BDNF in this process, and describe preliminary findings from our lab implicating BDNF in the process of selecting of newly born cells for survival.
Advani, Tushar; Koek, Wouter; Hensler, Julie G
Two mild stress paradigms were used in the present study: acute (i.e. three injections of saline over 24 h) and subchronic (i.e. single daily injection of saline for 7 d). These mild stress procedures did not alter the behaviour of wild-type mice in the forced swim test. However, male BDNF+/- mice exhibited increased immobility in the forced swim test after mild stress. This genotypic difference in stress responsivity was also evident in plasma corticosterone levels after a single injection of saline. The behaviour of female mice of either genotype was not altered by mild stress, and there was no genotypic difference in the corticosterone response of female mice to a single saline injection. Male BDNF+/- mice should be a useful model in which to examine behavioural and neurochemical consequences of interactions among genetic and environmental factors implicated in stress-related affective disorders, such as major depression.
Croce, Nicoletta; Gelfo, Francesca; Ciotti, Maria Teresa; Federici, Giorgio; Caltagirone, Carlo; Bernardini, Sergio; Angelucci, Francesco
Using in vitro models of Alzheimer's disease (AD), we found that the toxic effects of amyloid beta 25-35 (Aβ(25-35)) on the neurotrophin brain-derived neurotrophic factor (BDNF) were counteracted by pre-incubation with neuropeptide Y (NPY), a neuropeptide expressed within the central nervous system. Nonetheless, the mechanism of action of NPY on BDNF neuronal production in the presence of Aβ is not known. BDNF expression might be directly regulated by microRNA (miRs), small non-coding DNA fragments that regulate the expression of target genes. Thus, there is the possibility that miRs alterations are present in AD-affected neurons and that NPY influences miR expression. To test this hypothesis, we exposed NPY-pretreated primary rat cortical neurons to Aβ(25-35) and measured miR-30a-5p (a member of the miR-30a family involved in BDNF tuning expression) and BDNF mRNA and protein expression after 24 and 48 h. Our results demonstrated that pre-treatment with NPY decreased miR-30a-5p expression and increased BDNF mRNA and protein expression at 24 and 48 h of incubation with Aβ. Therefore, this study demonstrates that NPY modulates BDNF and its regulating microRNA miR-30a-5p in opposite direction with a mechanism that possibly contributes to the neuroprotective effect of NPY in rat cortical neurons exposed to Aβ.
Full Text Available Abstract Background Brain-derived neurotrophic factor (BDNF is a potent neurotrophic factor that is implicated in the regulation of food intake and body weight. Polyunsaturated fatty acids (PUFAs localised in cell membranes have been shown to alter the levels of BDNF in the brain, suggesting that PUFAs and BDNF could have physical interaction with each other. To decipher the molecular mechanism through which PUFAs modulates BDNF’s activity, molecular docking was performed for BDNF with PUFAs and its metabolites, with 4-Methyl Catechol as a control. Results Inferring from molecular docking studies, lipoxin A4 (LXA4, and a known anti-inflammatory bioactive metabolite derived from PUFAs, with a binding energy of −3.98 Kcal/mol and dissociation constant of 1.2mM showed highest binding affinity for BDNF in comparison to other PUFAs and metabolites considered in the study. Further, the residues Lys 18, Thr 20, Ala 21, Val 22, Phe 46, Glu 48, Lys 50, Lys 58, Thr 75, Gln 77, Arg 97 and Ile 98 form hot point motif, which on interaction enhances BDNF’s function. Conclusion These results suggest that PUFAs and their metabolites especially, LXA4, modulate insulin resistance by establishing a physical interaction with BDNF. Similar interaction(s was noted between BDNF and resolvins and protectins but were of lesser intensity compared to LXA4.
Sánchez-Huertas, Carlos; Rico, Beatriz
In the cerebral cortex, the functional output of projection neurons is fine-tuned by inhibitory neurons present in the network, which use γ-aminobutyric acid (GABA) as their main neurotransmitter. Previous studies have suggested that the expression levels of the rate-limiting GABA synthetic enzyme, GAD65, depend on brain derived neurotrophic factor (BDNF)/TrkB activation. However, the molecular mechanisms by which this neurotrophic factor and its receptor controls GABA synthesis are still unknown. Here, we show a direct regulation of the GAD65 gene by BDNF-TrkB signaling via CREB in cortical interneurons. Conditional ablation of TrkB in cortical interneurons causes a cell-autonomous decrease in the synaptically enriched GAD65 protein and its transcripts levels, suggesting that transcriptional regulation of the GAD65 gene is altered. Dissection of the intracellular pathway that underlies this process revealed that BDNF/TrkB signaling controls the transcription of GAD65 in a Ras-ERK-CREB-dependent manner. Our study reveals a novel molecular mechanism through which BDNF/TrkB signaling may modulate the maturation and function of cortical inhibitory circuits.
Ghiglieri, Veronica; Sgobio, Carmelo; Patassini, Stefano; Bagetta, Vincenza; Fejtova, Anna; Giampà, Carmela; Marinucci, Silvia; Heyden, Alexandra; Gundelfinger, Eckart D; Fusco, Francesca R; Calabresi, Paolo; Picconi, Barbara
In mice lacking the central domain of the presynaptic scaffold Bassoon the occurrence of repeated cortical seizures induces cell-type-specific plasticity changes resulting in a general enhancement of the feedforward inhibition within the striatal microcircuit. Early antiepileptic treatment with valproic acid (VPA) reduces epileptic attacks, inhibits the emergence of pathological form of plasticity in fast-spiking (FS) interneurons and restores physiological striatal synaptic plasticity in medium spiny (MS) neurons. Brain-derived neurotrophic factor (BDNF) is a key factor for the induction and maintenance of synaptic plasticity and it is also implicated in the mechanisms underlying epilepsy-induced adaptive changes. In this study, we explore the possibility that the TrkB/BDNF system is involved in the striatal modifications associated with the Bassoon gene (Bsn) mutation. In epileptic mice abnormal striatum-dependent learning was paralleled by higher TrkB levels and an altered distribution of BDNF. Accordingly, subchronic intrastriatal administration of k252a, an inhibitor of TrkB receptor tyrosine kinase activity, reversed behavioral alterations in Bsn mutant mice. In addition, in vitro manipulations of the TrkB/BDNF complex by k252a, prevented the emergence of pathological plasticity in FS interneurons. Chronic treatment with VPA, by reducing seizures, was able to rebalance TrkB to control levels favoring a physiological redistribution of BDNF between MS neurons and FS interneurons with a concomitant recovery of striatal plasticity. Our results provide the first indication that BDNF is involved in determining the striatal alterations occurring in the early-onset epileptic syndrome associated with the absence of presynaptic protein Bassoon.
Danzer, S C; Pan, E; Nef, S; Parada, L F; McNamara, J O
Brain-derived neurotrophic factor (BDNF) and its cognate receptor tyrosine kinase B (TrkB) play important roles in regulating survival, structure, and function of CNS neurons. One method of studying the functions of these molecules has utilized in vitro hippocampal slice preparations. An important caveat to using slices, however, is that slice preparation itself might alter the expression of BDNF, thereby confounding experimental results. To address this concern, BDNF immunoreactivity was examined in rodent slices using two different methods of slice preparation. Rapid and anatomically selective regulation of BDNF content followed slice preparation using both methodologies; however, different patterns of altered BDNF immunoreactivity were observed. First, in cultured slices, BDNF content decreased in the dentate molecular layer and increased in the CA3 pyramidal cell layer and the mossy fiber pathway of the hippocampus after 30 min. Furthermore, an initially "punctate" pattern of BDNF labeling observed in the mossy fiber pathway of control sections changed to homogenous labeling of the pathway in vitro. In contrast to these findings, slices prepared as for acute slice physiology exhibited no change in BDNF content in the molecular layer and mossy fiber pathway 30 min after slicing, but exhibited significant increases in the dentate granule and CA3 pyramidal cell layers. These findings demonstrate that BDNF protein content is altered following slice preparation, that different methods of slice preparation produce different patterns of BDNF regulation, and raise the possibility that BDNF release and TrkB activation may also be regulated. These consequences of hippocampal slice preparation may confound analyses of exogenous or endogenous BDNF on hippocampal neuronal structure or function.
Tyagi, Ethika; Zhuang, Yumei; Agrawal, Rahul; Ying, Zhe; Gomez-Pinilla, Fernando
Quality nutrition during the period of brain formation is a predictor of brain functional capacity and plasticity during adulthood; however it is not clear how this conferred plasticity imparts long-term neural resilience. Here we report that early exposure to dietary omega-3 fatty acids orchestrates key interactions between metabolic signals and Bdnf methylation creating a reservoir of neuroplasticity that can protect the brain against the deleterious effects of switching to a Western diet (WD). We observed that the switch to a WD increased Bdnf methylation specific to exon IV, in proportion to anxiety-like behavior, in Sprague Dawley rats reared in low omega-3 fatty acid diet, and these effects were abolished by the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine. Blocking methylation also counteracted the reducing action of WD on the transcription regulator CTCF binding to Bdnf promoter IV. In vitro studies confirmed that CTCF binding to Bdnf promoter IV is essential for the action of DHA on BDNF regulation. Diet is also intrinsically associated to cell metabolism, and here we show that the switch to WD downregulated cell metabolism (NAD/NADH ratio and SIRT1). The fact that DNA methyltransferase inhibitor did not alter these parameters suggests they occur upstream to methylation. In turn, the methylation inhibitor counteracted the action of WD on PGC-1α, a mitochondrial transcription co-activator and BDNF regulator, suggesting that PGC-1α is an effector of Bdnf methylation. Results support a model in which diet can build an "epigenetic memory" during brain formation that confers resilience to metabolic perturbations occurring in adulthood.
Lehto, Kelli; Mäestu, Jarek; Kiive, Evelyn; Veidebaum, Toomas; Harro, Jaanus
The brain-derived neurotrophic factor gene (BDNF) Val66Met polymorphism and life stress have been associated with negative emotionality (e.g., neuroticism), but relevant evidence is far from unequivocal. Possible confounding factors include the type and timing of stressful events measured, such as childhood adversity vs. recent stressful events, and variable gene × environment interactions. The aim of this study was to longitudinally assess the BDNF Val66Met polymorphism and environment interaction effect on neuroticism in a population representative sample, depending upon the type of stress, gender and family relations. In the original older cohort of the Estonian Children Personality Behavior and Health Study (ECPBHS, n=593), neuroticism was measured at age 15 (parental assessment), 18 and 25 (self-assessments). Childhood stress was reported at age 15, quality of family relations was measured at age 18, and recent stressful life events at age 25. The BDNF Val66Met polymorphism interacted with recent stressful life events, but not with childhood adversities, to impact neuroticism. Interestingly, in female participants, neuroticism at age 18 predicted future stressful life events dependent upon genotype: individuals with Val/Val genotype and high neuroticism experienced higher, but Met-allele carriers with high neuroticism lower stress exposure at age 25. Similar tendencies were observed using parental assessments at age 15. The protective effect of Met-allele in the high stress exposure group could result from better early family environment. In conclusion, we herewith provide further evidence for a role of BDNF gene variance contributing to plasticity in response to environmental demands.
Sajjad Karim; Arif Ali
AIM: To study the alterations in p53 gene among Indian gastric cancer patients and to correlate them with the various clinicopathological parameters.METHODS: A total of 103 gastric cancer patients were included in this study. The p53 alterations were studied by both immunohistochemical method as well as polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. We only studied four (exon 5, 6, 7, and 8) of the 11 p53 exons. The alterations in p53 were also correlated with respect to various clinicopathological parameters.RESULTS: Among 103 cases, p53 over-expression and alteration were detected in 37 (35.92%) and 19 (18.44%) cases, respectively. Most of the p53 alterations were found at exon 5 (31.54%), followed by exon 6 (26.31%), exon 7 (21.04%) and exon 8 (21.04%). A significant correlation of p53 overexpression was found with p53 alteration ( P = 0.000).Concordance between p53 alteration (as detected by SSCP) and over-expression [as detected by immunohistochemistry (IHC)] was found in 75% cases.We found that IHC-positive/SSCP-negative cases accounted for 21% of cases and IHC-negative/SSCPpositive cases accounted for remaining 4% cases.CONCLUSION: Our results show that p53 gene mutations are significantly correlated with p53 protein over-expression, with 75% concordance in overexpression and alteration in the p53 gene, but 25% disconcordance also cautions against the assumption that p53 over-expression is always associated with a gene mutation. There may be other mechanisms responsible for stabilization and accumulation of p53 protein with no evidence of gene mutation that reflect an accumulation of a non-mutated protein, or a false negative SSCP result.
de Cid, R; Fonseca, F; Gratacòs, M; Gutierrez, F; Martín-Santos, R; Estivill, X; Torrens, M
Brain-derived neurotrophic factor (BDNF) signaling pathways have been shown to be essential for opioid-induced plasticity. We conducted an exploratory study to evaluate BDNF variability in opioid addict responders and nonresponders to methadone maintenance treatment (MMT). We analyzed 21 single nucleotide polymorphisms (SNPs) across the BDNF genomic region. Responders and nonresponders were classified by means of illicit opioid consumption detected in random urinalysis. Patients were assessed by a structured interview (Psychiatric Research Interview for Substance and Mental Disorders (PRISM)-DSM-IV) and personality was evaluated by the Cloninger's Temperament and Character Inventory. No clinical, environmental and treatment characteristics were different between the groups, except for the Cooperativeness dimension (P < 0.001). Haplotype block analysis showed a low-frequency (2.7%) haplotype (13 SNPs) in block 1, which was more frequent in the nonresponder group than in the responder group (4/42 vs. 1/135; P(corrected) = 0.023). Fine mapping in block 1 allows us to identify a haplotype subset formed by only six SNPs (rs7127507, rs1967554, rs11030118, rs988748, rs2030324 and rs11030119) associated with differential response to MMT (global P sim = 0.011). Carriers of the CCGCCG haplotype had an increased risk of poorer response, even after adjusting for Cooperativeness score (OR = 20.25 95% CI 1.46-280.50, P = 0.025). These preliminary results might suggest the involvement of BDNF as a factor to be taken into account in the response to MMT independently of personality traits, environmental cues, methadone dosage and psychiatric comorbidity.
Yen Ying Lim
Full Text Available OBJECTIVE: Cross-sectional genetic association studies have reported equivocal results on the relationship between the brain-derived neurotrophic factor (BDNF Val66Met and risk of Alzheimer's disease (AD. As AD is a neurodegenerative disease, genetic influences may become clearer from prospective study. We aimed to determine whether BDNF Val66Met polymorphism influences changes in memory performance, hippocampal volume, and Aβ accumulation in adults with amnestic mild cognitive impairment (aMCI and high Aβ. METHODS: Thirty-four adults with aMCI were recruited from the Australian, Imaging, Biomarkers and Lifestyle (AIBL Study. Participants underwent PiB-PET and structural MRI neuroimaging, neuropsychological assessments and BDNF genotyping at baseline, 18 month, and 36 month assessments. RESULTS: In individuals with aMCI and high Aβ, Met carriers showed significant and large decline in episodic memory (d = 0.90, p = .020 and hippocampal volume (d = 0.98, p = .035. BDNF Val66Met was unrelated to the rate of Aβ accumulation (d = -0.35, p = .401. CONCLUSIONS: Although preliminary due to the small sample size, results of this study suggest that high Aβ levels and Met carriage may be useful prognostic markers of accelerated decline in episodic memory, and reductions in hippocampal volume in individuals in the prodromal or MCI stage of AD.
Carballedo, Angela; Morris, Derek; Zill, Peter; Fahey, Ciara; Reinhold, Elena; Meisenzahl, Eva; Bondy, Brigitta; Gill, Michael; Möller, Hans-Jürgen; Frodl, Thomas
The interaction between adverse life events during childhood and genetic factors is associated with a higher risk to develop major depressive disorder (MDD). One of the polymorphisms found to be associated with MDD is the Val66MET polymorphism of brain-derived neurotrophic factor (BDNF). The aim of our two-center study was to determine how the BDNF Val66Met polymorphism and childhood adversity affect the volumetric measures of the hippocampus in healthy individuals and people with MDD. In this two-center study, 62 adult patients with MDD and 71 healthy matched controls underwent high-resolution magnetic resonance imaging. We used manual tracing of the bilateral hippocampal structure with help of the software BRAINS2, assessed childhood adversity using the Childhood Trauma Questionnaire and genotyped Val66Met BDNF SNP (rs6265). MDD patients had smaller hippocampal volumes, both in the left and right hemispheres (F = 5.4, P = 0.022). We also found a significant interaction between BDNF allele and history of childhood adversity (F = 6.1, P = 0.015): Met allele carriers in our samples showed significantly smaller hippocampal volumes when they did have a history of childhood adversity, both in patients and controls. Our results highlight how relevant stress-gene interactions are for hippocampal volume reductions. Subjects exposed to early life adversity developed smaller hippocampal volumes when they carry the Met-allele of the BDNF polymorphism.
Full Text Available Brain Derived Neurotrophic Factor (BDNF is a neurotrophin that has been related not only to neurodevelopment and neuroprotection, but also to synapse regulation, learning and memory. Research focused on the neurobiology of schizophrenia has emphasized the relevance of neurodevelompental and neurotoxicity-related elements in the pathogenesis of this disease. Research focused on the clinical features of schizophrenia in the past decades has emphasized the relevance of cognitive deficits of this illness, considered a core manifestation and an important predictor for functional outcome. Variations in neurotrophins such as BDNF may have a role as part of the molecular mechanisms underlying these processes, from the neurodevelopmental alterations to the molecular mechanisms of cognitive dysfunction in patients with schizophrenia.
Ventskovska, Olena; Porkka-Heiskanen, Tarja; Karpova, Nina N
Brain-derived neurotrophic factor (Bdnf) regulates neuronal plasticity, slow wave activity and sleep homeostasis. Environmental stimuli control Bdnf expression through epigenetic mechanisms, but there are no data on epigenetic regulation of Bdnf by sleep or sleep deprivation. Here we investigated whether 5-methylcytosine (5mC) DNA modification at Bdnf promoters p1, p4 and p9 influences Bdnf1, Bdnf4 and Bdnf9a expression during the normal inactive phase or after sleep deprivation (SD) (3, 6 and 12 h, end-times being ZT3, ZT6 and ZT12) in rats in two brain areas involved in sleep regulation, the basal forebrain and cortex. We found a daytime variation in cortical Bdnf expression: Bdnf1 expression was highest at ZT6 and Bdnf4 lowest at ZT12. Such variation was not observed in the basal forebrain. Also Bdnf p1 and p9 methylation levels differed only in the cortex, while Bdnf p4 methylation did not vary in either area. Factorial analysis revealed that sleep deprivation significantly induced Bdnf1 and Bdnf4 with the similar pattern for Bdnf9a in both basal forebrain and cortex; 12 h of sleep deprivation decreased 5mC levels at the cortical Bdnf p4 and p9. Regression analysis between the 5mC promoter levels and the corresponding Bdnf transcript expression revealed significant negative correlations for the basal forebrain Bdnf1 and cortical Bdnf9a transcripts in only non-deprived rats, while these correlations were lost after sleep deprivation. Our results suggest that Bdnf transcription during the light phase of undisturbed sleep-wake cycle but not after SD is regulated at least partially by brain site-specific DNA methylation.
Jeanblanc, Jerome; He, Dao-Yao; Carnicella, Sebastien; Kharazia, Viktor; Janak, Patricia H; Ron, Dorit
We previously found that brain-derived neurotrophic factor (BDNF) haplodeficient mice exhibit greater ethanol-induced place preference and psychomotor sensitization, and greater ethanol consumption after deprivation. We further observed that, in mice, voluntary ethanol intake increases BDNF expression in the dorsal striatum (DS). Here, we determined whether BDNF within the DS regulates ethanol self-administration in Long Evans rats trained to self-administer a 10% ethanol solution. We observe...
Full Text Available BACKGROUND: Sleep plays a pivotal role in normal biological functions. Sleep loss results in higher stress vulnerability and is often found in mental disorders. There is evidence that brain-derived neurotrophic factor (BDNF could be a central player in this relationship. Recently, we could demonstrate that subjects suffering from current symptoms of insomnia exhibited significantly decreased serum BDNF levels compared with sleep-healthy controls. In accordance with the paradigm indicating a link between sleep and BDNF, we aimed to investigate if the stress system influences the association between sleep and BDNF. METHODOLOGY/PRINCIPAL FINDINGS: Participants with current symptoms of insomnia plus a former diagnosis of Restless Legs Syndrome (RLS and/or Periodic Limb Movement (PLM and sleep healthy controls were included in the study. They completed questionnaires on sleep (ISI, Insomnia Severity Index and stress (PSS, Perceived Stress Scale and provided a blood sample for determination of serum BDNF. We found a significant interaction between stress and insomnia with an impact on serum BDNF levels. Moreover, insomnia severity groups and score on the PSS each revealed a significant main effect on serum BDNF levels. Insomnia severity was associated with increased stress experience affecting serum BDNF levels. Of note, the association between stress and BDNF was only observed in subjects without insomnia. Using a mediation model, sleep was revealed as a mediator of the association between stress experience and serum BDNF levels. CONCLUSIONS: This is the first study to show that the interplay between stress and sleep impacts BDNF levels, suggesting an important role of this relationship in the pathogenesis of stress-associated mental disorders. Hence, we suggest sleep as a key mediator at the connection between stress and BDNF. Whether sleep is maintained or disturbed might explain why some individuals are able to handle a certain stress load while
Béjot, Yannick; Tessier, Anne; Cachia, Claire; Giroud, Maurice; Mossiat, Claude; Bertrand, Nathalie; Garnier, Philippe; Marie, Christine
International audience; Although brain-derived neurotrophic factor (BDNF) plays a central role in recovery after cerebral ischemia, little is known about cells involved in BDNF production after stroke. The present study testes the hypothesis that neurons are not the unique source of neosynthesized BDNF after stroke and that non neuronal-BDNF producing cells differ according to the delay after stroke induction. For this purpose, cellular localization of BDNF and BDNF content of each hemisphere...
Greenberg, Michael E.; Xu, Baoji; Lu, Bai; Hempstead, Barbara L.
BDNF has pleiotrophic effects on neuronal development and synaptic plasticity that underlie circuit formation and cognitive function. Recent breakthroughs reveal that neuronal activity regulates BDNF cell biology, including Bdnf transcription, dendritic targeting and trafficking of BDNF mRNA and protein, and secretion and extracellular conversion of proBDNF to mature BDNF. Defects in these mechanisms contribute differentially to cognitive dysfunction and anxiety–like behaviors. Here we review...
Nagappan, Guhan; Zaitsev, Eugene; Senatorov, Vladimir V.; Yang, Jianmin; Hempstead, Barbara L.; Lu, Bai
Pro- and mature neurotrophins often elicit opposing biological effects. For example, mature brain-derived neurotrophic factor (mBDNF) is critical for long-term potentiation induced by high-frequency stimulation, whereas proBDNF facilitate long-term depression induced by low-frequency stimulation. Because mBDNF is derived from proBDNF by endoproteolytic cleavage, mechanisms regulating the cleavage of proBDNF may control the direction of BDNF regulation. Using methods that selectively detect pr...
Antonio Di Lieto
Full Text Available BACKGROUND: Previous studies suggest that the responsiveness of TrkB receptor to BDNF is developmentally regulated in rats. Antidepressant drugs (AD have been shown to increase TrkB signalling in the adult rodent brain, and recent findings implicate a BDNF-independent mechanism behind this phenomenon. When administered during early postnatal life, ADs produce long-lasting biochemical and behavioural alterations that are observed in adult animals. METHODOLOGY: We have here examined the responsiveness of brain TrkB receptors to BDNF and ADs during early postnatal life of mouse, measured as autophosphorylation of TrkB (pTrkB. PRINCIPAL FINDINGS: We found that ADs fail to induce TrkB signalling before postnatal day 12 (P12 after which an adult response of TrkB to ADs was observed. Interestingly, there was a temporally inverse correlation between the appearance of the responsiveness of TrkB to systemic ADs and the marked developmental reduction of BDNF-induced TrkB in brain microslices ex vivo. Basal p-TrkB status in the brain of BDNF deficient mice was significantly reduced only during early postnatal period. Enhancing cAMP (cyclic adenosine monophosphate signalling failed to facilitate TrkB responsiveness to BDNF. Reduced responsiveness of TrkB to BDNF was not produced by the developmental increase in the expression of dominant-negative truncated TrkB.T1 because this reduction was similarly observed in the brain microslices of trkB.T1(-/- mice. Moreover, postnatal AD administration produced long-lasting behavioural alterations observable in adult mice, but the responses were different when mice were treated during the time when ADs did not (P4-9 or did (P16-21 activate TrkB. CONCLUSIONS: We have found that ADs induce the activation of TrkB only in mice older than 2 weeks and that responsiveness of brain microslices to BDNF is reduced during the same time period. Exposure to ADs before and after the age when ADs activate TrkB produces differential
Hazra, Somoday; Kumar, Sourav; Saha, Goutam Kumar
Objective The aims of the present study were to explore the behavioural effects and to understand the possible mode of action of Bacopa monnieri extract (BME) on chronic unpredictable stress (CUS) induced depressive model and the biochemical alterations such as brain derived neurotrophic factor (BDNF), Akt, cyclic-AMP response element binding (CREB) protein level in the hippocampus of rats. Methods We examined the effects of chronic administration of BME on CUS exposed rats for 28 days. Behavioural changes were assessed by sucrose consumption and open field test to assess the effect of BME on CUS-induced depression. The mechanisms underlying antidepressant like action of BME was further evaluated by measuring levels of BDNF, Akt, and CREB in the hippocampus of rat brain and compared with the standard tricyclic antidepressant drug imipramine (20 mg/kg body weight). Results Exposure to CUS for 28 days produced depression-like behavior in rats, as indicated by significant decreases in sucrose consumption, locomotor activity including decreased BDNF, Akt and CREB levels in the hippocampus. Daily administration of BME at a dose of (80 mg/kg body weight) significantly reverses the behavioral alteration and restored the normal level of BDNF, total and phospho-Akt, total and phospho CREB in the hippocampus of CUS induced rats as compared to vehicle treated control rats. Conclusion These findings suggest that BME ameliorates CUS induced behavioural depression in rats and that can be used as a potent therapeutic agent in treating depressive like behavior. PMID:28096878
Je, H Shawn; Yang, Feng; Ji, Yuanyuan; Nagappan, Guhan; Hempstead, Barbara L; Lu, Bai
Formation of specific neuronal connections often involves competition between adjacent axons, leading to stabilization of the active terminal, while retraction of the less active ones. The underlying molecular mechanisms remain unknown. We show that activity-dependent conversion of pro-brain-derived neurotrophic factor (proBDNF) to mature (m)BDNF mediates synaptic competition. Stimulation of motoneurons triggers proteolytic conversion of proBDNF to mBDNF at nerve terminals. In Xenopus nerve-muscle cocultures, in which two motoneurons innervate one myocyte, proBDNF-p75(NTR) signaling promotes retraction of the less active terminal, whereas mBDNF-tyrosine-related kinase B (TrkB) p75NTR (p75 neurotrophin receptor) facilitates stabilization of the active one. Thus, proBDNF and mBDNF may serve as potential "punishment" and "reward" signals for inactive and active terminals, respectively, and activity-dependent conversion of proBDNF to mBDNF may regulate synapse elimination.
In the current study effect of nicotine on expression of neurotrophins, brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) has been studied in hippocampus and frontal cortex during development of brain in rats. Neurotrophins are factors that help in development of brain among which BDNF and NGF are very important, expressed at different stages during the developmental process. Different sedatives are reported to alter the expression of these factors. In this study, three groups of neonate rats (1-5, 5-10 and 10-15 days age) were used each having 20 rats. Ten were subjected to a dose of 66 μg of nicotine while other ten received the same amount of saline at the same time interval. Then expression of the BDNF and NGF was observed in hippocampus and frontal cortex tissue using immunoassay. Western blotting was used to observe the presence of BDNF in hippocampus as well as frontal cortex. In all groups there was a significant decrease in concentration of neurotrophic factors where nicotine was applied as compared to control. The highest expression of BDNF and NGF in hippocampus and frontal cortex was observed in 10-15 days group (G3) and in 5-10 group (G2) as compared to the control, P BDNF and it effects the development of brain in neonates that can further impair brain functions.
Montalbano, Giuseppe; Mania, Manuela; Guerrera, Maria Cristina; Abbate, Francesco; Laurà, Rosaria; Navarra, Michele; Vega, Jose A; Ciriaco, Emilia; Germanà, Antonino
Obesity is a multifactorial disease generated by an alteration in balance between energy intake and expenditure, also dependent on genetic and non-genetic factors. Moreover, various nuclei of the hypothalamus receive and process peripheral stimuli from the gastrointestinal tract, controlling food intake and therefore energy balance. Among anorexigenic molecules, brain-derived neurotrophic factor (BDNF) acts through the tyrosine-kinase receptor TrkB. Numerous data demonstrate that the BDNF/TrkB system has a fundamental role in the control of food intake and body weight. Quantitative PCR and immunohistochemistry for both BDNF and TrkB were used to determine changes in levels in the brain and gastro-intestinal tract of an experimental zebrafish model of diet-induced obesity. Overfed animals showed increased weight and body mass index as well as accumulation of adipose tissue in the visceral, subcutaneous and hepatic areas. These changes were concomitant with decreased levels of BDNF mRNA in the gastro-intestinal tract and increased expression of TrkB mRNA in the brain. Overfeeding did not change the density of cells displaying immunoreactivity for BDNF or TrkB in the brain although both were significantly diminished in the gastro-intestinal tract. These results suggest an involvement of the BDNF/TrkB system in the regulation of food intake and energy balance in zebrafish, as in mammals.
Anna Maria Lavezzi
Full Text Available Experimental studies have demonstrated that the neurotrophin brain-derived neutrophic factor (BDNF is required for the appropriate development of the central respiratory network, a neuronal complex in the brainstem of vital importance to sustaining life. The pontine Kölliker-Fuse nucleus (KFN is a fundamental component of this circuitry with strong implications in the pre- and postnatal breathing control. This study provides detailed account for the cytoarchitecture, the physiology and the BDNF behaviour of the human KFN in perinatal age. We applied immunohistochemistry in formalin-fixed and paraffin-embedded brainstem samples (from 45 fetuses and newborns died of both known and unknown causes, to analyze BDNF, gliosis and apoptosis patterns of manifestation. The KFN showed clear signs of developmental immaturity, prevalently associated to BDNF altered expression, in high percentages of sudden intrauterine unexplained death syndrome (SIUDS and sudden infant death syndrome (SIDS victims. Our results indicate that BDNF pathway dysfunctions can derange the normal KFN development so preventing the breathing control in the sudden perinatal death.The data presented here are also relevant to a better understanding of how the BDNF expression in the KFN can be involved in several human respiratory pathologies such as the Rett’s and the congenital central hypoventilation syndromes.
Rokamp, Kim Z; Staalsø, Jonatan M; Gartmann, Martin
Variation in genes encoding the ß2-adrenergic receptor (ADRB2) and angiotensin-converting enzyme (ACE) may influence Q¿ (cardiac output). The 46G>A (G16R) SNP (single nucleotide polymorphism) has been associated with ß2-mediated vasodilation, but the effect of ADRB2 haplotypes on Q¿ has not been...... studied. Five SNPs within ADRB2 (46G>A, 79C>G, 491C>T, 523C>A and 1053G>C by a pairwise tagging principle) and the I/D (insertion/deletion) polymorphism in ACE were genotyped in 143 subjects. Cardiovascular variables were evaluated by the Model flow method at rest and during incremental cycling exercise...
Gomar, Jesus J; Conejero-Goldberg, Concepcion; Huey, Edward D; Davies, Peter; Goldberg, Terry E
Compromises in compensatory neurobiologic mechanisms due to aging and/or genetic factors (i.e., APOE gene) may influence brain-derived neurotrophic factor (BDNF) val66met polymorphism effects on temporal lobe morphometry and memory performance. We studied 2 cohorts from Alzheimer's Disease Neuroimaging Initiative: 175 healthy subjects and 222 with prodromal and established Alzheimer's disease. Yearly structural magnetic resonance imaging and cognitive performance assessments were carried out over 3 years of follow-up. Both cohorts had similar BDNF Val/Val and Met allele carriers' (including both Val/Met and Met/Met individuals) distribution. In healthy subjects, a significant trend for thinner posterior cingulate and precuneus cortices was detected in Met carriers compared to Val homozygotes in APOE E4 carriers, with large and medium effect sizes, respectively. The mild cognitive impairment/Alzheimer's disease cohort showed a longitudinal decline in entorhinal thickness in BDNF Met carriers compared to Val/Val in APOE E4 carriers, with effect sizes ranging from medium to large. In addition, an effect of BDNF genotype was found in APOE E4 carriers for episodic memory (logical memory and ADAS-Cog) and semantic fluency measures, with Met carriers performing worse in all cases. These findings suggest a lack of compensatory mechanisms in BDNF Met carriers and APOE E4 carriers in healthy and pathological aging.
O'Donnell, Kieran J; Glover, Vivette; Holbrook, Joanna D; O'Connor, Thomas G
Multiple behavioral and health outcomes, including internalizing symptoms, may be predicted from prenatal maternal anxiety, depression, or stress. However, not all children are affected, and those that are can be affected in different ways. Here we test the hypothesis that the effects of prenatal anxiety are moderated by genetic variation in the child's brain-derived neurotrophic factor (BDNF) gene, using the Avon Longitudinal Study of Parents and Children population cohort. Internalizing symptoms were assessed from 4 to 13 years of age using the Strengths and Difficulties Questionnaire (n = 8,584); a clinical interview with the adolescents was conducted at age 15 years (n = 4,704). Obstetric and psychosocial risk and postnatal maternal symptoms were included as covariates. Results show that prenatal maternal anxiety predicted internalizing symptoms, including with the diagnostic assessment at 15 years. There was a main effect of two BDNF polymorphisms (rs6265 [val66met] and rs11030104) on internalizing symptoms up to age 13. There was also genetic moderation of the prenatal anxiety effect by different BDNF polymorphisms (rs11030121 and rs7124442), although significant effects were limited to preadolescence. The findings suggest a role for BDNF gene-environment interactions in individual vulnerability to the effects of prenatal anxiety on child internalizing symptoms.
Elevation of BDNF exon I-specific transcripts in the frontal cortex and midbrain of rat during spontaneous morphine withdrawal is accompanied by enhanced pCreb1 occupancy at the corresponding promoter.
Peregud, Danil I; Panchenko, Leonid F; Gulyaeva, Natalia V
Brain-derived neurotrophic factor (BDNF) is believed to play a crucial role in the mechanisms underlying opiate dependence; however, little is known about specific features and mechanisms regulating its expression in the brain under these conditions. The aim of this study was to investigate the effects of acute morphine intoxication and withdrawal from chronic intoxication on expression of BDNF exon I-, II-, IV-, VI- and IX-containing transcripts in the rat frontal cortex and midbrain. We also have studied whether alterations of BDNF exon-specific transcripts are accompanied by changes in association of well-known transcriptional regulators of BDNF gene-phosphorylated (active form) cAMP response element binding protein (pCreb1) and methyl-CpG binding protein 2 (MeCP2) with corresponding regulatory regions of the BDNF gene. Acute morphine intoxication did not affect levels of BDNF exons in brain regions, while spontaneous morphine withdrawal in dependent rats was accompanied by an elevation of the BDNF exon I-containing mRNAs both in the frontal cortex and midbrain. During spontaneous morphine withdrawal, increased associations of pCreb1 were found with promoter of exon I in the frontal cortex and promoters of exon I, IV and VI in the midbrain. The association of MeCP2 with BDNF promoters during spontaneous morphine withdrawal did not change. Thus, BDNF exon-specific transcripts are differentially expressed in brain regions during spontaneous morphine withdrawal in dependent rats and pCreb1 may be at least partially responsible for these alterations.
Full Text Available Cognitive capacities decline with age, an event accompanied by the altered transcription of synaptic plasticity genes. Here, we show that the transcriptional induction of Bdnf by a mnemonic stimulus is impaired in aged hippocampal neurons. Mechanistically, this defect is due to reduced NMDA receptor (NMDAR-mediated activation of CaMKII. Decreased NMDAR signaling prevents changes associated with activation at specific Bdnf promoters, including displacement of histone deacetylase 4, recruitment of the histone acetyltransferase CBP, increased H3K27 acetylation, and reduced H3K27 trimethylation. The decrease in NMDA-CaMKII signaling arises from constitutive reduction of synaptic cholesterol that occurs with normal aging. Increasing the levels of neuronal cholesterol in aged neurons in vitro, ex vivo, and in vivo restored NMDA-induced Bdnf expression and chromatin remodeling. Furthermore, pharmacological prevention of age-associated cholesterol reduction rescued signaling and cognitive deficits of aged mice. Thus, reducing hippocampal cholesterol loss may represent a therapeutic approach to reverse cognitive decline during aging.
Full Text Available MK-801, also known as dizocilpine, is a noncompetitive N-methyl-D-aspartic acid (NMDA receptor antagonist that induces schizophrenia-like symptoms. While astrocytes have been implicated in the pathophysiology of psychiatric disorders, including schizophrenia, astrocytic responses to MK-801 and their significance to schizotypic symptoms are unclear. Changes in the expression levels of glial fibrillary acid protein (GFAP, a marker of astrocyte activation in response to a variety of pathogenic stimuli, were examined in the hippocampus of rats treated with the repeated MK-801 injection (0.5 mg/10 ml/kg body weight for 6 days and in primary cultured hippocampal astrocytes incubated with MK-801 (5 or 20 μM for 24 h. Moreover, the expression levels of BDNF and its receptors TrkB and p75 were examined in MK-801-treated astrocyte cultures. MK-801 treatment enhanced GFAP expression in the rat hippocampus and also increased the levels of GFAP protein and mRNA in hippocampal astrocytes in vitro. Treatment of cultured hippocampal astrocytes with MK-801 enhanced protein and mRNA levels of BDNF, TrkB, and p75. Collectively, our results suggest that hippocampal astrocytes may contribute to the pathophysiology of schizophrenia symptoms associated with NMDA receptor hypofunction by reactive transformation and altered BDNF signaling.
Vignoli, Beatrice; Canossa, Marco
ABSTRACT We have recently reported that long-term memory retention requires synaptic glia for proBDNF uptake and recycling. Through the recycling course, glial cells release endocytic BDNF, a mechanism that is activated in response to glutamate via AMPA and mGluRI/II receptors. Cortical astrocytes express receptors for many different transmitters suggesting for a complex signaling controlling endocytic BDNF secretion. Here, we demonstrated that the extracellular nucleotide ATP, activating P2X and P2Y receptors, regulates endocytic BDNF secretion in cultured astrocytes. Our data indicate that distinct glioactive molecules can participate in BDNF glial recycling and suggest that cortical astrocytes contributing to neuronal plasticity can be influenced by neurotransmitters in tune with synaptic needs.
Seifert, Thomas; Brassard, Patrice; Wissenberg, Mads
The circulating level of brain-derived neurotrophic factor (BDNF) is reduced in patients with major depression and type-2 diabetes. Because acute exercise increases BDNF production in the hippocampus and cerebral cortex, we hypothesized that endurance training would enhance the release of BDNF from...... the human brain as detected from arterial and internal jugular venous blood samples. In a randomized controlled study, 12 healthy sedentary males carried out 3 mo of endurance training (n = 7) or served as controls (n = 5). Before and after the intervention, blood samples were obtained at rest and during...... exercise. At baseline, the training group (58 + or - 106 ng x 100 g(-1) x min(-1), means + or - SD) and the control group (12 + or - 17 ng x 100 g(-1) x min(-1)) had a similar release of BDNF from the brain at rest. Three months of endurance training enhanced the resting release of BDNF to 206 + or - 108...
Macbeth, Abbe H; Scharfman, Helen E; Maclusky, Neil J; Gautreaux, Claris; Luine, Victoria N
Recognition memory and anxiety were examined in nulliparous (NP: 0 litters) and multiparous (MP: 5-6 litters) middle-aged female rats (12 months old) to assess possible enduring effects of multiparity at least 3 months after the last litter was weaned. MP females performed significantly better than NP females on the non-spatial memory task, object recognition, and the spatial memory task, object placement. Anxiety as measured on the elevated plus maze did not differ between groups. Monoaminergic activity and levels were measured in prefrontal cortex, CA1 hippocampus, CA3 hippocampus, and olfactory bulb (OB). NP and MP females differed in monoamine concentrations in the OB only, with MP females having significantly greater concentrations of dopamine and metabolite DOPAC, norepinephrine and metabolite MHPG, and the serotonin metabolite 5-HIAA, as compared to NP females. These results indicate a long-term change in OB neurochemistry as a result of multiparity. Brain-derived neurotrophic factor (BDNF) was also measured in hippocampus (CA1, CA3, dentate gyrus) and septum. MP females had higher BDNF levels in both CA1 and septum; as these regions are implicated in memory performance, elevated BDNF may underlie the observed memory task differences. Thus, MP females (experiencing multiple bouts of pregnancy, birth, and pup rearing during the first year of life) displayed enhanced memory task performance but equal anxiety responses, as compared to NP females. These results are consistent with previous studies showing long-term changes in behavioral function in MP, as compared to NP, rats and suggest that alterations in monoamines and a neurotrophin, BDNF, may contribute to the observed behavioral changes.
Schunck, Rebeca Vargas Antunes; Torres, Iraci L S; Laste, Gabriela; de Souza, Andressa; Macedo, Isabel Cristina; Valle, Marina Tuerlinckx Costa; Salomón, Janaína L O; Moreira, Sonia; Kuo, Jonnsin; Arbo, Marcelo Dutra; Dallegrave, Eliane; Leal, Mirna Bainy
Exposure to ethanol alters the expression of brain-derived neurotrophic factor (BDNF) in central regions such as, the hippocampus, cortex and striatum. Moreover, chronic alcohol intake is known to induce selective neuronal damage associated with an increase in the inflammatory cascade, resulting in neuronal apoptosis and neurodegeneration. In the present study, we investigated the nociceptive response after 24h of protracted alcohol abstinence. Rats were submitted to a model of alcohol withdrawal syndrome and the nociceptive response was assessed by the tail-flick and the hot plate tests. In addition, we evaluated BDNF and interleukin-10 (IL-10) in the cerebral prefrontal cortex, brainstem and hippocampus of rats after protracted alcohol abstinence. Male adult Wistar rats were divided into three groups: non-treated group (control group), treated with water (water group), and alcohol (alcohol group). The water and alcohol administrations were done by oral gavage and were performed over three periods of five days of treatment with two intervals of two days between them. Alcohol (20%w/v) was given at 4g/kg of body weight. There was a significant effect of treatment in the tail-flick and hot plate latencies with greater latencies in alcohol-treated rats after 10days of abstinence. There was a significant increase in the prefrontal cortex BDNF levels in the alcohol group in relation to the water group, after 11days of alcohol abstinence. In addition, alcohol withdrawal induced a significant increase in the hippocampus, prefrontal cortex and brainstem IL-10 levels compared with control group. Thus, the present study demonstrates that protracted alcohol withdrawal produced an analgesic effect indexed via increased nociceptive threshold. We suggest that these effects could be related to the increased levels of BDNF and IL-10 observed in the central nervous system.
N Lale Satiroglu-Tufan; Ferda Bir; Nese Calli-Demirkan
AIM: To investigate both whether the risk of gastric cancer is associated with the Ile/Val single nucleotide polymorphism (SNP) of human epidermal growth factor receptor-2 (HER-2) transmembrane domain-coding region at codon 655 and the suggested existence of HER-2 expression in gastric cancer cases in a Turkish patient group.METHODS: Polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP)strategy was used to analyze the presence ofHER-2 SNP at codon 655. c-erbB-2 expression pattern was analyzed by immunohistochemistry. The results were compared between gastric carcinoma group and chronic gastritis group, as well as between clinicopathological parameters and carcinoma.RESULTS: Results showed that Ile/Val genotype accounted for 20% within the Turkish gastric carcinoma group, and none in chronic gastritis group, and this genotyping was associated with stage Ⅳ gastric cancers (P = 0.04). Positive membranous HER-2 immunoreactivity, on the other hand, accounted for 24% within the Turkish gastric carcinoma group and none from chronic gastritis cases; further, it was correlated with intestinal type carcinomas (P = 0.007), and stage Ⅲ-Ⅳ carcinomas (P = 0.004).CONCLUSION: These observations imply that the tested HER-2 SNP may participate in the development and progression of gastric cancer. Thus, after confirming these results with large sample groups, HER-2 codon 655 SNP and/or c-erbB-2 overexpression may also be used as a poor prognostic indicator for gastric carcinomas.
Kotlęga, Dariusz; Peda, Barbara; Zembroń-Łacny, Agnieszka; Gołąb-Janowska, Monika; Nowacki, Przemysław
Stroke is the main cause of motoric and neuropsychological disability in adults. Recent advances in research into the role of the brain-derived neurotrophic factor in neuroplasticity, neuroprotection and neurogenesis might provide important information for the development of new poststroke-rehabilitation strategies. It plays a role as a mediator in motor learning and rehabilitation after stroke. Concentrations of BDNF are lower in acute ischemic-stroke patients compared to controls. Lower levels of BDNF are correlated with an increased risk of stroke, worse functional outcomes and higher mortality. BDNF signalling is dependent on the genetic variation which could affect an individual's response to recovery after stroke. Several single nucleotide polymorphisms of the BDNF gene have been studied with regard to stroke patients, but most papers analyse the rs6265 which results in a change from valine to methionine in the precursor protein. Subsequently a reduction in BDNF activity is observed. There are studies indicating the role of this polymorphism in brain plasticity, functional and morphological changes in the brain. It may affect the risk of ischemic stroke, post-stroke outcomes and the efficacy of the rehabilitation process within physical exercise and transcranial magnetic stimulation. There is a consistent trend of Met alleles' being connected with worse outcomes and prognoses after stroke. However, there is no satisfactory data confirming the importance of Met allele in stroke epidemiology and the post-stroke rehabilitation process. We present the current data on the role of BDNF and polymorphisms of the BDNF gene in stroke patients, concentrating on human studies.
Minigo, Gabriela; Flanagan, Katie L.; Slattery, Robyn M.; Plebanski, Magdalena
Many pathogens, including the malaria parasite Plasmodium falciparum, display high levels of polymorphism within T-cell epitope regions of proteins associated with protective immunity. The T-cell epitope variants are often non-cross-reactive. Herein, we show in a murine model, which modifies a protective CD8 T-cell epitope from the circumsporozoite protein (CS) of Plasmodium berghei (SYIPSAEKI), that simultaneous or sequential co-stimulation with two of its putative similarly non-cross-reactive altered peptide ligand (APL) epitopes (SYIPSAEDI or SYIPSAEAI) has radically different effects on immunity. Hence, co-immunization or sequential stimulation in vivo of SYIPSAEKI with its APL antagonist SYIPSAEDI decreases immunity to both epitopes. By contrast, co-immunization with SYIPSAEAI has no apparent initial effect, but it renders the immune response to SYIPSAEKI resistant to being turned off by subsequent immunization with SYIPSAEDI. These results suggest a novel strategy for vaccines that target polymorphic epitopes potentially capable of mutual immune interference in the field, by initiating an immune response by co-immunization with the desired index epitope, together with a carefully selected “potentiator” APL peptide.
Gomes da Silva, Sérgio; de Almeida, Alexandre Aparecido; Fernandes, Jansen; Lopim, Glauber Menezes; Cabral, Francisco Romero; Scerni, Débora Amado; de Oliveira-Pinto, Ana Virgínia; Lent, Roberto; Arida, Ricardo Mario
Clinical evidence has shown that physical exercise during pregnancy may alter brain development and improve cognitive function of offspring. However, the mechanisms through which maternal exercise might promote such effects are not well understood. The present study examined levels of brain-derived neurotrophic factor (BDNF) and absolute cell…
Papaleo, Francesco; Silverman, Jill L.; Aney, Jordan; Tian, Qingjun; Barkan, Charlotte L.; Chadman, Kathryn K.; Crawley, Jacqueline N.
BDNF regulates components of cognitive processes and has been implicated in psychiatric disorders. Here we report that genetic overexpression of the BDNF mature isoform (BDNF-tg) in female mice impaired working memory functions while sparing components of fear conditioning. BDNF-tg mice also displayed reduced breeding efficiency, higher…
Xu, Hang; Zhang, Yu; Zhang, Fan; Yuan, San-na; Shao, Feng; Wang, Weiwen
Early stress is a significant risk factor for the onset of mood disorders such as depression during adulthood. Impairments in cognitive flexibility mediated by prefrontal cortex (PFC) dysfunction are increasingly recognized as important etiological and pathological factors in the development of depression. Our previous study demonstrated that social defeat stress during early adolescence produced delayed deficits in cognitive flexibility in adult mice. The potential molecular mechanisms underlying these long-term consequences remain unclear. One candidate molecule is brain-derived neurotrophic factor (BDNF), which plays a vital role in neural development and synaptic plasticity. In this study, we initially examined the effects of adolescent social stress on cognitive flexibility and PFC BDNF expression within a week after the last stress exposure and 6 weeks later during adulthood. Adolescent (PND 28) male mice were subjected to stress or control manipulation for 10 days. The attentional set-shifting task (AST) was used to assess cognitive flexibility. Levels of BDNF mRNA and protein in the PFC were examined after behavioral testing. The results demonstrated that previously stressed mice exhibited delayed extra-dimensional set-shifting deficits in AST when tested as adults but not when tested as adolescents. Consistent with the cognitive alterations, adolescent stress induced dynamic alterations in BDNF expression in the medial PFC (mPFC), with a transient increase observed shortly after the stress, followed by a decrease 6 weeks later during adulthood. Next, we further determined the effects of chronic treatment with the antidepressant duloxetine during early adulthood on cognitive and molecular alterations induced by adolescent stress. Compared with the controls, duloxetine treatment reversed the cognitive deficits and increased the BDNF protein expression in the mPFC during adulthood in previously stressed mice. These findings demonstrated that BDNF expression
Balasubramanian, Priya; Subramanian, Madhan; Nunez, Joseph L; Mohankumar, Sheba M J; Mohankumar, P S
Changes in serum estradiol levels are associated with mood disorders in women. However, the underlying mechanisms are not clear. Because alterations in Brain-Derived Neurotrophic Factor (BDNF) and monoamine levels in the hippocampus and amygdala have been associated with anxiety disorders, we hypothesized that chronic treatment with a low dose of estradiol would cause anxiety-like disorder by altering BDNF and monoamine levels in these regions. To test this hypothesis, female rats were sham-implanted (Controls) or implanted with pellets that release estradiol-17β (E2) for 90-days at the rate of 20 ng/day. Animals underwent behavioral tests such as the open field test and elevated plus maze test at the end of treatment. Brains from these animals were frozen, sectioned and the hippocampus, central amygdala and caudate putamen were microdissected and analyzed for monoamine levels using HPLC. BDNF protein levels in these areas were measured using ELISA and BDNF mRNA levels were analyzed using RT-PCR. In the open field test, animals chronically treated with E2 displayed anxiety-like behavior that was marked by a decrease in the number of inner zone crossings and increase in the rate of defecation compared to controls. However, no behavioral changes were observed in the elevated plus maze test. Chronic E2 treatment also decreased BDNF protein and mRNA levels in the central amygdala that was accompanied by a reduction in dopamine levels. No changes were observed in the hippocampus and caudate putamen. These results suggest that BDNF and dopamine in the central amygdala might possibly mediate chronic E2-induced behavioral alterations.
Greenberg, Michael E; Xu, Baoji; Lu, Bai; Hempstead, Barbara L
BDNF has pleiotropic effects on neuronal development and synaptic plasticity that underlie circuit formation and cognitive function. Recent breakthroughs reveal that neuronal activity regulates BDNF cell biology, including Bdnf transcription, dendritic targeting and trafficking of BDNF mRNA and protein, and secretion and extracellular conversion of proBDNF to mature BDNF. Defects in these mechanisms contribute differentially to cognitive dysfunction and anxiety-like behaviors. Here we review recent studies, presented at a symposium at Neuroscience 2009, that describe regulatory mechanisms that permit rapid and dynamic refinement of BDNF actions in neurons.
Association between peroxisome proliferator-activated receptor-γcoactivator-1α gene polymorphisms and type 2 diabetes in southern Chinese population: role of altered interaction with myocyte enhancer factor 2C
ZHANG Shao-ling; LU Wen-sheng; YAN Li; WU Mu-chao; XU Ming-tong; CHEN Li-hong; CHENG Hua
Background Some single nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptor-Y coactivator (PGC)-1α gene have been reported to be associated with type 2 diabetes in different populations, and studies on Chinese patients yielded controversial results. The objective of this case-control study was to explore the relationship between SNPs of PGC-1a and type 2 diabetes in the southern Chinese population and to determine whether the common variants: Gly482Ser and Thr394Thr, in the PGC-1α gene have any impacts on interaction with myocyte enhancer factor (MEF) 2C.Methods The SNPs in all exons of the PGC-1α gene was investigated in 50 type 2 diabetic patients using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) and direct sequencing. Thereafter, 263 type 2diabetic patients and 282 healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A bacterial two-hybrid system and site-directed mutagenesis were used to investigate whether Gly482Ser and Thr394Thr variants in the PGC-1α gene alter the interaction with MEF2C.Results Three frequent SNPs (Thr394Thr, Gly482Ser and Thr528Thr) were found in exons of the PGC-1α gene. Only the Gly482Ser variant had a different distribution between diabetic patients and healthy subjects, with the 482Ser allele more frequent in patients than in controls (40.1% vs 29.3%, P＜0.01). Even in controls, the 482Ser(A) carriers were more likely to have higher levels of total cholesterol and low-density lipoprotein cholesterol than the 482Gly(G) carriers. The 394A-482G-528A haplotype was associated with protection from diabetes, while the 394A-482A-528A was associated with the susceptibility to diabetes. The bacterial two-hybrid system and site-directed mutagenesis revealed that the 482Ser variant was less efficient than the 482Gly variant to interact with MEF2C, whereas the 394Thr (A) had a synergic effect on the interaction between
Tamura, Shogo [Graduate School of Health Sciences, Hokkaido University, Sapporo (Japan); Research Fellow of the Japan Society for the Promotion of Science, Tokyo (Japan); Nagasawa, Ayumi; Masuda, Yuya; Tsunematsu, Tetsuya [Graduate School of Health Sciences, Hokkaido University, Sapporo (Japan); Hayasaka, Koji; Matsuno, Kazuhiko; Shimizu, Chikara [Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo (Japan); Ozaki, Yukio [Department of Clinical and Laboratory Medicine, Faculty of Medicine, University of Yamanashi (Japan); Moriyama, Takanori, E-mail: email@example.com [Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Sapporo (Japan)
Highlights: Black-Right-Pointing-Pointer It has been thought that BDNF is not produced in the megakaryocytic lineage. Black-Right-Pointing-Pointer MEG-01 produces BDNF upon TPO stimulation and regulates its proliferation. Black-Right-Pointing-Pointer BDNF accelerates proliferation of MEG-01 in an autocrine manner. Black-Right-Pointing-Pointer BDNF may be an autocrine MEG-CSF, which regulates megakaryopoiesis. -- Abstract: While human platelets release endogenous brain-derived neurotrophic factor (BDNF) upon activation, a previous report on MEG-01, a megakaryocytic cell line, found no trace of BDNF production, and the pathophysiological function of platelet BDNF has remained elusive. In the present study, we demonstrate that MEG-01 produces BDNF in the presence of TPO and that this serves to potentiate cell proliferation. Our in vitro findings suggest that BDNF regulates MEG-01 proliferation in an autocrine manner, and we suggest that BDNF may be a physiological autocrine regulator of megakaryocyte progenitors.
Trajkovska, V; Santini, M A; Marcussen, Anders Bue;
Both brain-derived neurotrophic factor (BDNF) and the serotonin receptor 2A (5-HT(2A)) have been related to depression pathology. Specific 5-HT(2A) receptor changes seen in BDNF conditional mutant mice suggest that BDNF regulates the 5-HT(2A) receptor level. Here we show a direct effect of BDNF...... on 5-HT(2A) receptor protein levels in primary hippocampal neuronal and mature hippocampal organotypic cultures exposed to different BDNF concentrations for either 1, 3, 5 or 7 days. In vivo effects of BDNF on hippocampal 5-HT(2A) receptor levels were further corroborated in (BDNF +/-) mice...... with reduced BDNF levels. In primary neuronal cultures, 7 days exposure to 25 and 50ng/mL BDNF resulted in downregulation of 5-HT(2A), but not of 5-HT(1A), receptor protein levels. The BDNF-associated downregulation of 5-HT(2A) receptor levels was also observed in mature hippocampal organotypic cultures...
Izabela Guimarães Barbosa
Full Text Available INTRODUCTION: Bipolar disorder (BD is a prevalent, chronic and progressive illness. There is a growing body of evidence indicating that brain-derived neurotrophic factor (BDNF plays an important role in the pathophysiology of BD. OBJECTIVE: The aim of this study was to evaluate BDNF plasma levels in BD patients with long term illness in comparison with controls. METHODS: 87 BD type I patients and 58 controls matched by age, gender and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of BDNF were measured by ELISA. RESULTS: On average, patients had suffered from BD for 23.4 years. In comparison with controls, BD patients with mania presented a 1.90-fold increase in BDNF plasma levels (p = .001, while BD patients in remission presented a 1.64-fold increase in BDNF plasma levels (p = .03. BDNF plasma levels were not influenced by age, length of illness or current medications. CONCLUSIONS: The present study suggests that long-term BD patients exhibit increased circulating levels of BDNF.
Xu, Lifang; Zhang, Ziyin; Xie, Tianhua; Zhang, Xiaoyang; Dai, Tu
Background: Brain-derived neurotrophic factor (BDNF) protects retinal ganglion cells against ischemia in ocular degenerative diseases. We aimed to determine the effect of BDNF-AS on the ischemic injury of retinal ganglion cells. Methods: The levels of BDNF and BDNF-AS were measured in retinal ganglion cells subjected to oxygen and glucose deprivation. The lentiviral vectors were constructed to either overexpress or knock out BDNF-AS. The luciferase reporter gene assay was used to determine wh...
Dalton, Elizabeth D; Hammen, Constance L; Najman, Jake M; Brennan, Patricia A
Functional genetic polymorphisms associated with Brain-Derived Neurotrophic Factor (BDNF) and serotonin (5-HTTLPR) have demonstrated associations with depression in interaction with environmental stressors. In light of evidence for biological connections between BDNF and serotonin, it is prudent to consider genetic epistasis between variants in these genes in the development of depressive symptoms. The current study examined the effects of val66met, 5-HTTLPR, and family environment quality on youth depressive symptoms in adolescence and young adulthood in a longitudinal sample oversampled for maternal depression history. A differential susceptibility model was tested, comparing the effects of family environment on depression scores across different levels of a cumulative plasticity genotype, defined as presence of both, either, or neither plasticity alleles (defined here as val66met Met and 5-HTTLPR 'S'). Cumulative plasticity genotype interacted with family environment quality to predict depression among males and females at age 15. After age 15, however, the interaction of cumulative plasticity genotype and early family environment quality was only predictive of depression among females. Results supported a differential susceptibility model at age 15, such that plasticity allele presence was associated with more or less depressive symptoms depending on valence of the family environment, and a diathesis-stress model of gene-environment interaction after age 15. These findings, although preliminary because of the small sample size, support prior results indicating interactive effects of 5-HTTLPR, val66met, and environmental stress, and suggest that family environment may have a stronger influence on genetically susceptible women than men.
Full Text Available Anxiety disorders (ADs are disabling chronic disorders with exaggerated behavioral response to threats. This study was aimed at testing the hypothesis that ADs may be associated with reduced neurotrophic activity, particularly of Brain-derived neurotrophic factor (BDNF, and determining possible effects of genetics on serum BDNF concentrations. In 672 adult subjects from six isolated villages in North-Eastern Italy with high inbreeding, we determined serum BDNF levels and identified subjects with different ADs subtypes such as Social and Specific Phobias (PHSOC, PHSP, Generalized Anxiety Disorder (GAD, and Panic Disorder (PAD. Analysis of the population as a whole or individual village showed no significant correlation between serum BDNF levels and Val66Met polymorphism and no association with anxiety levels. Stratification of subjects highlighted a significant decrease in serum BDNF in females with GAD and males with PHSP. This study indicates low heritability and absence of any impact of the Val66Met polymorphism on circulating concentrations of BDNF. Our results show that BDNF is not a general biomarker of anxiety but serum BDNF levels correlate in a gender-specific manner with ADs subtypes.
Full Text Available Highly specific activity-dependent neuronal responses are necessary for modulating synapses to facilitate learning and memory. We present evidence linking a number of important processes involved in regulating synaptic plasticity, suggesting a mechanistic pathway whereby activity-dependent signaling, likely through protein kinase C (PKC-mediated phosphorylation of HuD, can relieve basal repression of Bdnf mRNA translation in dendrites, allowing for increased TrkB signaling and synaptic remodeling. We demonstrate that the neuronal ELAV family of RNA binding proteins associates in vivo with several Bdnf mRNA isoforms present in the adult brain in an activity-dependent manner, and that one member, HuD, interacts directly with sequences in the long Bdnf 3' untranslated region (3'UTR and co-localizes with Bdnf mRNA in dendrites of hippocampal neurons. Activation of PKC leads to increased dendritic translation of mRNAs containing the long Bdnf 3'UTR, a process that is dependent on the presence of HuD and its phosphorylation at threonine residues 149 and/or 165. Thus, we found a direct effect of HuD on regulating translation of dendritic Bdnf mRNAs to mediate local and activity-dependent increases in dendritic BDNF synthesis.
Catherine A Smith
Full Text Available Early developmental exposure to di(2-ethylhexyl phthalate (DEHP has been linked to a variety of neurodevelopmental changes, particularly in rodents. The primary goal of this work was to establish whether acute postnatal exposure to a low dose of DEHP would alter hippocampal dendritic morphology and BDNF and caspase-3 mRNA expression in male and female Long Evans rats. Treatment with DEHP in male rats led to a reduction in spine density on basal and apical dendrites of neurons in the CA3 dorsal hippocampal region compared to vehicle-treated male controls. Dorsal hippocampal BDNF mRNA expression was also down-regulated in male rats exposed to DEHP. No differences in hippocampal spine density or BDNF mRNA expression were observed in female rats treated with DEHP compared to controls. DEHP treatment did not affect hippocampal caspase-3 mRNA expression in male or female rats. These results suggest a gender-specific vulnerability to early developmental DEHP exposure in male rats whereby postnatal DEHP exposure may interfere with normal synaptogenesis and connectivity in the hippocampus. Decreased expression of BDNF mRNA may represent a molecular mechanism underlying the reduction in dendritic spine density observed in hippocampal CA3 neurons. These findings provide initial evidence for a link between developmental exposure to DEHP, reduced levels of BDNF and hippocampal atrophy in male rats.
Smith, Catherine A; Holahan, Matthew R
Early developmental exposure to di(2-ethylhexyl) phthalate (DEHP) has been linked to a variety of neurodevelopmental changes, particularly in rodents. The primary goal of this work was to establish whether acute postnatal exposure to a low dose of DEHP would alter hippocampal dendritic morphology and BDNF and caspase-3 mRNA expression in male and female Long Evans rats. Treatment with DEHP in male rats led to a reduction in spine density on basal and apical dendrites of neurons in the CA3 dorsal hippocampal region compared to vehicle-treated male controls. Dorsal hippocampal BDNF mRNA expression was also down-regulated in male rats exposed to DEHP. No differences in hippocampal spine density or BDNF mRNA expression were observed in female rats treated with DEHP compared to controls. DEHP treatment did not affect hippocampal caspase-3 mRNA expression in male or female rats. These results suggest a gender-specific vulnerability to early developmental DEHP exposure in male rats whereby postnatal DEHP exposure may interfere with normal synaptogenesis and connectivity in the hippocampus. Decreased expression of BDNF mRNA may represent a molecular mechanism underlying the reduction in dendritic spine density observed in hippocampal CA3 neurons. These findings provide initial evidence for a link between developmental exposure to DEHP, reduced levels of BDNF and hippocampal atrophy in male rats.
safety and flexibility at the level of multi-object systems. We are granted the flexibility of using different families of kinds of objects, and we are guaranteed the safety of the combination. This paper highlights the inability of traditional polymorphism to handle multiple objects, and presents family...... polymorphism as a way to overcome this problem. Family polymorphism has been implemented in the programming language gbeta, a generalized version of Beta, and the source code of this implementation is available under GPL....
Baj, Gabriele; D'Alessandro, Valentina; Musazzi, Laura; Mallei, Alessandra; Sartori, Cesar R; Sciancalepore, Marina; Tardito, Daniela; Langone, Francesco; Popoli, Maurizio; Tongiorgi, Enrico
Brain-derived neurotrophic factor (BDNF) is encoded by multiple BDNF transcripts, whose function is unclear. We recently showed that a subset of BDNF transcripts can traffic into distal dendrites in response to electrical activity, while others are segregated into the somatoproximal domains. Physical exercise and antidepressant treatments exert their beneficial effects through upregulation of BDNF, which is required to support survival and differentiation of newborn dentate gyrus (DG) neurons...
Choy, Kwok Ho Christopher; de Visser, Yvonne; Nichols, Nancy R; van den Buuse, Maarten
Epidemiological studies suggest that multiple developmental disruptions are involved in the etiology of psychiatric illnesses including schizophrenia. In addition, altered expression of brain-derived neurotrophic factor (BDNF) has been implicated in these illnesses. In the present study, we examined the combined long-term effect of an early stress, in the form of maternal deprivation, and a later stress, simulated by chronic young-adult treatment with the stress hormone, corticosterone, on BDNF expression in the hippocampus of rats. To assess whether there were behavioral effects, which may correlate with the BDNF changes, learning and memory was tested in the Y-maze test for short term spatial memory, the Morris water maze for long-term spatial memory, and the T-maze test for working memory. Four groups of rats received either no stress, maternal deprivation, corticosterone treatment, or both. Dorsal hippocampus sections obtained from parallel groups were used for BDNF mRNA in situ hybridization. Rats which had undergone both maternal deprivation and corticosterone treatment displayed a unique and significant 25-35% reduction of BDNF expression in the dentate gyrus (DG), and similar trends in the CA1 and CA3 regions of the hippocampus. These "two-hit" animals exhibited a learning delay in the Morris water maze test, a marked deficit in the Y-maze, but little change in the T-maze test. However, some aspects of cognition were also altered in rats with either maternal deprivation or corticosterone treatment. This study demonstrates a persistent effect of two developmental disruptions on BDNF expression in the hippocampus, with parallel, but not completely correlative changes in learning and memory.
Egervari, Gabor; Jutras-Aswad, Didier; Landry, Joseph; Miller, Michael L; Anderson, Sarah Ann; Michaelides, Michael; Jacobs, Michelle M; Peter, Cyril; Yiannoulos, Georgia; Liu, Xun; Hurd, Yasmin L
Genetic factors impact behavioral traits relevant to numerous psychiatric disorders and risk-taking behaviors, and different lines of evidence have indicated that discrete neurobiological systems contribute to such individual differences. In this study, we explored the relationship of genetic variants of the prodynorphin (PDYN) gene, which is enriched in the striatonigral/striatomesencephalic pathway, a key neuronal circuit implicated in positive 'Go' behavioral choice and action. Our multidisciplinary approach revealed that the single nucleotide polymorphism (SNP) rs2235749 (in high linkage disequilibrium with rs910080) modifies striatal PDYN expression via impaired binding of miR-365, a microRNA that targets the PDYN 3'-untranslated region (3'UTR), and is significantly associated to novelty- and reward-related behavioral traits in humans and translational animal models. Carriers of the rs2235749G allele exhibited increased levels of PDYN 3'UTR in vitro and had elevated mRNA expression in the medial nucleus accumbens shell (NAcSh) and caudate nucleus in postmortem human brains. There was an association of rs2235749 with novelty-seeking trait and a strong genotype-dose association with positive reinforcement behavior in control subjects, which differed in cannabis-dependent individuals. Using lentiviral miRZip-365 constructs selectively expressed in Pdyn-neurons of the NAcSh, we demonstrated that the Pdyn-miR365 interaction in the NAcSh directly influences novelty-seeking exploratory behavior and facilitates self-administration of natural reward. Overall, this translational study suggests that genetically determined miR-365-mediated epigenetic regulation of PDYN expression in mesolimbic striatonigral/striatomesencephalic circuits possibly contributes to novelty seeking and positive reinforcement traits.
Serra, Stefano; Zheng, Lei; Hassan, Manal; Phan, Alexandria T; Woodhouse, Linda J; Yao, James C; Ezzat, Shereen; Asa, Sylvia L
Pancreatic neuroendocrine tumors (pNET), also known as islet cell tumors, exhibit a wide range of biologic behaviors ranging from long dormancy to rapid progression. Currently, there are few molecular biomarkers that can be used to predict recurrence/metastasis or response to therapy. This study examined the predictive and prognostic value of a single nucleotide polymorphism substituting an arginine (R) for glycine (G) in codon 388 of the FGFR4 transmembrane domain. We established the FGFR4 genotype of 71 patients with pNETs and correlated genotype with biologic behavior. We created an in vivo model of pNET with BON1 cells and transfected them with either FGFR4-G388 or FGFR4-R388 to determine the mechanism of action and to examine response to the mTOR inhibitor everolimus. We then validated the predictive results of experimental studies in a group of patients treated with everolimus. FGFR4-R388 is associated with more aggressive clinical behavior in patients with pNETs with a statistically significant higher risk of advanced tumor stage and liver metastasis. Using an orthotopic mouse xenograft model, we show that FGFR4-R388 promotes tumor progression by increasing intraperitoneal spread and metastatic growth within the liver. Unlike FGFR4-G388, FGFR4-R388 BON1 tumors exhibited diminished responsiveness to everolimus. Concordantly, there was a statistically significant reduction in response to everolimus in patients with FGFR4-R388. Our findings highlight the importance of the FGFR4 allele in pNET progression and identify a predictive marker of potential therapeutic importance in this disease.
Full Text Available Abstract Background Numerous single nucleotide polymorphisms (SNPs associated with complex diseases have been identified by genome-wide association studies (GWAS and expression quantitative trait loci (eQTLs studies. However, few of these SNPs have explicit biological functions. Recent studies indicated that the SNPs within the 3’UTR regions of susceptibility genes could affect complex traits/diseases by affecting the function of miRNAs. These 3’UTR SNPs are functional candidates and therefore of interest to GWAS and eQTL researchers. Description We developed a publicly available online database, MirSNP (http://cmbi.bjmu.edu.cn/mirsnp, which is a collection of human SNPs in predicted miRNA-mRNA binding sites. We identified 414,510 SNPs that might affect miRNA-mRNA binding. Annotations were added to these SNPs to predict whether a SNP within the target site would decrease/break or enhance/create an miRNA-mRNA binding site. By applying MirSNP database to three brain eQTL data sets, we identified four unreported SNPs (rs3087822, rs13042, rs1058381, and rs1058398, which might affect miRNA binding and thus affect the expression of their host genes in the brain. We also applied the MirSNP database to our GWAS for schizophrenia: seven predicted miRNA-related SNPs (p Conclusion MirSNP could identify the putative miRNA-related SNPs from GWAS and eQTLs researches and provide the direction for subsequent functional researches.
Lim, Yen Ying; Hassenstab, Jason; Cruchaga, Carlos; Goate, Alison; Fagan, Anne M; Benzinger, Tammie L S; Maruff, Paul; Snyder, Peter J; Masters, Colin L; Allegri, Ricardo; Chhatwal, Jasmeer; Farlow, Martin R; Graff-Radford, Neill R; Laske, Christoph; Levin, Johannes; McDade, Eric; Ringman, John M; Rossor, Martin; Salloway, Stephen; Schofield, Peter R; Holtzman, David M; Morris, John C; Bateman, Randall J
SEE ROGAEVA AND SCHMITT-ULMS DOI101093/AWW201 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: The brain-derived neurotrophic factor (BDNF) Val66Met polymorphism is implicated in synaptic excitation and neuronal integrity, and has previously been shown to moderate amyloid-β-related memory decline and hippocampal atrophy in preclinical sporadic Alzheimer's disease. However, the effect of BDNF in autosomal dominant Alzheimer's disease is unknown. We aimed to determine the effect of BDNF Val66Met on cognitive function, hippocampal function, tau and amyloid-β in preclinical autosomal dominant Alzheimer's disease. We explored effects of apolipoprotein E (APOE) ε4 on these relationships. The Dominantly Inherited Alzheimer Network conducted clinical, neuropsychological, genetic, biomarker and neuroimaging measures at baseline in 131 mutation non-carriers and 143 preclinical autosomal dominant Alzheimer's disease mutation carriers on average 12 years before clinical symptom onset. BDNF genotype data were obtained for mutation carriers (95 Val66 homozygotes, 48 Met66 carriers). Among preclinical mutation carriers, Met66 carriers had worse memory performance, lower hippocampal glucose metabolism and increased levels of cerebrospinal fluid tau and phosphorylated tau (p-tau) than Val66 homozygotes. Cortical amyloid-β and cerebrospinal fluid amyloid-β42 levels were significantly different from non-carriers but did not differ between preclinical mutation carrier Val66 homozygotes and Met66 carriers. There was an effect of APOE on amyloid-β levels, but not cognitive function, glucose metabolism or tau. As in sporadic Alzheimer's disease, the deleterious effects of amyloid-β on memory, hippocampal function, and tau in preclinical autosomal dominant Alzheimer's disease mutation carriers are greater in Met66 carriers. To date, this is the only genetic factor found to moderate downstream effects of amyloid-β in autosomal dominant Alzheimer's disease.
Davis, Margaret I.
Brain Derived Neurotrophic Factor (BDNF) has emerged as a regulator of development, plasticity and, recently, addiction. Decreased neurotrophic activity may be involved in ethanol-induced neurodegeneration in the adult brain and in the etiology of alcohol-related neurodevelopmental disorders. This can occur through decreased expression of BDNF or through inability of the receptor to transduce signals in the presence of ethanol. In contrast, recent studies implicate region-specific up-regulati...
Full Text Available Abstract Background The pathogenic role of brain derived neurotrophic factor (BDNF in the incisional pain is poorly understood. The present study explores the role of the BDNF in the incision-induced pain hypersensitivity. Methods A longitudinal incision was made in one plantar hind paw of isoflurane-anesthetized rats. Dorsal root ganglias (DRG and spinal cords were removed at various postoperative times (1–72 h. Expression pattern of BDNF was determined by immunohistochemistry and double-labeling immunofluorescence. Lidocaine-induced blockade of sciatic nerve function was used to determine the importance of afferent nerve activity on BDNF expression in the DRG and spinal cord after incision. BDNF antibody was administered intrathecally (IT or intraperitoneal (IP to modulate the spinal BDNF or peripheral BDNF after incision. Results After hind-paw incision, the BDNF was upregulated in the ipsilateral lumbar DRG and spinal cord whereas thoracic BDNF remained unchanged in response to incision. The upregulated BDNF was mainly expressed in the large-sized neurons in DRG and the neurons and the primary nerve terminals in the spinal cord. Sciatic nerve blockade prevented the increase of BDNF in the DRG and spinal cord. IT injection of BDNF antibody greatly inhibited the mechanical allodynia induced by incision whereas IP administration had only marginal effect. Conclusion The present study showed that incision induced the segmental upregulation of BDNF in the DRG and spinal cord through somatic afferent nerve transmission, and the upregulated BDNF contributed to the pain hypersensitivity induced by surgical incision.
Lapchak, P A; Araujo, D M; Hefti, F
Quantitative in situ hybridization was used to determine whether the prevalence or topographical distribution of brain-derived neurotrophic factor (BDNF) or tyrosine receptor kinase (trk) B mRNA is altered in the hippocampal formation following lesions of excitatory afferents from the entorhinal cortex which provides an external source of innervation for the hippocampal formation. BDNF mRNA levels were not altered in the hippocampal formation up to 10 days following entorhinal cortex lesions (ECLs). The levels of mRNA coding for all known forms of trkB receptors also remained unchanged. The prevalence of the synaptic plasticity marker SNAP-25 mRNA was increased in the CA2 and CA3 pyramidal cell layers and the dentate gyrus by 6 days following ECLs and remained elevated at 10 days following ECLs. Our findings indicate that hippocampal neuron sprouting which occurs in response to ECLs is not the result of changes in the expression of the BDNF or trkB mRNA.
Radiske, Andressa; Rossato, Janine I; Köhler, Cristiano A; Gonzalez, Maria Carolina; Medina, Jorge H; Cammarota, Martín
Therapies based on the impairment of reconsolidation or the enhancement of extinction offer the possibility of decreasing the persistent recollection of distressing memories. However, the direct interplay between reconsolidation and extinction has rarely been considered. Previously, we reported that reactivation induces reconsolidation of fear extinction memory. Here, using a step-down inhibitory avoidance learning paradigm in rats, we show that intrahippocampus infusion of function-blocking anti-BDNF antibody immediately or 6 h after extinction memory reactivation impairs the reconsolidation of extinction. Extinction memory reactivation increases proBDNF, BDNF, and tropomyosin receptor kinase B (TrkB) phosphorylation levels in dorsal CA1, while blocking BDNF maturation in the hippocampus with plasminogen activator inhibitor 1 hinders the persistence of extinction and induces the recurrence of fear. Moreover, coinfusion of recombinant BDNF (0.25 μg/side) after extinction memory reactivation impedes the recovery of the avoidance response induced by inhibiting gene expression and protein synthesis in the dorsal hippocampus. Our findings unravel a new role for BDNF, suggesting that this neurotrophin is necessary and sufficient to maintain the reactivated fear extinction engram.
Shen, Ji-Duo; Ma, Li-Gang; Hu, Chun-Yue; Pei, Yang-Yi; Jin, Shuang-Li; Fang, Xiao-Yan; Li, Yu-Cheng
Depression is increasingly become a global public healthy problem. This study was to investigate whether berberine could attenuate the depressive-like behavior induced by repeated corticosterone injection and explore the possible mechanisms. The present results showed that exogenous corticosterone injection caused depressive-like behaviors in mice, such as decreased sucrose intake in sucrose preference test (SPT) and increased immobility time in forced swimming test (FST). These behavioral alterations were accompanying with the decreased BDNF mRNA and protein levels in hippocampus and the elevated serum corticosterone levels. Treatment with berberine prevented these changes above. Our findings confirmed the antidepressant-like effect of berberine and suggested its mechanisms might be partially mediated by up-regulation of BDNF in hippocampus.
Full Text Available Posttraumatic stress disorder (PTSD is a debilitating condition that develops in some people after exposure to a traumatic event. Brain-derived neurotrophic factor (BDNF is highly expressed in the mammalian brain and is thought to be involved in learning and memory processes. A nonsynonymous polymorphism in the BDNF gene, rs6265 (Val66Met, has been hypothesised to be associated with PTSD. Association studies examining the Val66Met polymorphism and PTSD have been inconclusive, likely due to the variability in type of trauma exposure analysed. Vietnam veterans (n=257 screened for PTSD and controlled for trauma exposure were genotyped for BDNF Val66Met. The association was not significant so we incorporated our data into a meta-analysis to obtain greater statistical power. A comprehensive search of more than 1237 articles revealed eight additional studies suitable for meta-analysis (n=3625. A random-effects meta-analysis observed a potential protective factor of the Val/Val genotype. After removing two studies with violation of Hardy-Weinberg equilibrium, findings for the Val/Val genotype reached significance. Subgroup analyses confirmed a trend for this finding. Limitations of some studies that inform this meta-analysis include poorly screened controls and a lack of examination of population stratification. Effectively designed studies should inform this line of research in the future.
Wurzelmann, Mary; Romeika, Jennifer; Sun, Dong
Traumatic brain injury (TBI) is a major health problem worldwide. Following primary mechanical insults, a cascade of secondary injuries often leads to further neural tissue loss. Thus far there is no cure to rescue the damaged neural tissue. Current therapeutic strategies primarily target the secondary injuries focusing on neuroprotection and neuroregeneration. The neurotrophin brain-derived neurotrophic factor (BDNF) has significant effect in both aspects, promoting neuronal survival, synaptic plasticity and neurogenesis. Recently, the flavonoid 7,8-dihydroxyflavone (7,8-DHF), a small TrkB agonist that mimics BDNF function, has shown similar effects as BDNF in promoting neuronal survival and regeneration following TBI. Compared to BDNF, 7,8-DHF has a longer half-life and much smaller molecular size, capable of penetrating the blood-brain barrier, which makes it possible for non-invasive clinical application. In this review, we summarize functions of the BDNF/TrkB signaling pathway and studies examining the potential of BDNF and 7,8-DHF as a therapy for TBI.
Wurzelmann, Mary; Romeika, Jennifer; Sun, Dong
Traumatic brain injury (TBI) is a major health problem worldwide. Following primary mechanical insults, a cascade of secondary injuries often leads to further neural tissue loss. Thus far there is no cure to rescue the damaged neural tissue. Current therapeutic strategies primarily target the secondary injuries focusing on neuroprotection and neuroregeneration. The neurotrophin brain-derived neurotrophic factor (BDNF) has significant effect in both aspects, promoting neuronal survival, synaptic plasticity and neurogenesis. Recently, the flavonoid 7,8-dihydroxyflavone (7,8-DHF), a small TrkB agonist that mimics BDNF function, has shown similar effects as BDNF in promoting neuronal survival and regeneration following TBI. Compared to BDNF, 7,8-DHF has a longer half-life and much smaller molecular size, capable of penetrating the blood-brain barrier, which makes it possible for non-invasive clinical application. In this review, we summarize functions of the BDNF/TrkB signaling pathway and studies examining the potential of BDNF and 7,8-DHF as a therapy for TBI.
Sakata, Kazuko; Woo, Newton H.; Martinowich, Keri; Greene, Joshua S.; Schloesser, Robert J.; Shen, Liya; Lu, Bai
Transcription of Bdnf is controlled by multiple promoters, which drive expression of multiple transcripts encoding for the same protein. Promoter IV contributes significantly to activity-dependent brain-derived neurotrophic factor (BDNF) transcription. We have generated promoter IV mutant mice (BDNF-KIV) by inserting a GFP-STOP cassette within the Bdnf exon IV locus. This genetic manipulation results in disruption of promoter IV-mediated Bdnf expression. BDNF-KIV animals exhibited significant...
Zhang, L; Dhillon, H S; Barron, S; Hicks1, R R; Prasad, R M; Seroogy, K B
Previous evidence indicates that both chronic alcohol treatment and traumatic brain injury modulate expression of certain neurotrophins and neurotrophin receptors in cortical tissue. However, the combined effects of chronic alcohol and brain trauma on expression of neurotrophins and their receptors have not been investigated. In the present study, we examined the effects of 6 weeks of chronic ethanol administration on lateral fluid percussion (FP) brain injury-induced alterations in expression of mRNAs for the neurotrophin brain-derived neurotrophic factor (BDNF) and its high affinity receptor, trkB, in rat hippocampus. In both the control- (pair-fed isocaloric sucrose) diet and the chronic ethanol-diet groups, unilateral FP brain injury induced a bilateral increase in levels of both BDNF and trkB mRNAs in the dentate gyrus granule cell layer, and of BDNF mRNA in hippocampal region CA3. However, no significant differences in expression were found between the control-diet and ethanol-diet groups, in either the sham-injured or FP-injured animals. These findings suggest that 6 weeks of chronic ethanol administration does not alter the plasticity of hippocampal BDNF/trkB expression in response to experimental brain injury.
Full Text Available Complex regulation of brain-derived neurotrophic factor (BDNF governs its intricate functions in brain development and neuronal plasticity. Besides tight transcriptional control from multiple distinct promoters, alternative 3'end processing of the BDNF transcripts generates either a long or a short 3'untranslated region (3'UTR. Previous reports indicate that distinct RNA sequence in the BDNF 3'UTRs differentially regulates BDNF production in the brain to accommodate neuronal activity changes, conceivably through differential interactions with undefined trans-acting factors that regulate stability and translation of these BDNF mRNA isoforms. In this study, we report that the neuronal RNA-binding protein (RBP HuD interacts with a highly conserved AU-rich element (ARE specifically located in the BDNF long 3'UTR. Such interaction is necessary and sufficient for selective stabilization of mRNAs that contain the BDNF long 3'UTR in vitro and in vivo. Moreover, in a HuD transgenic mouse model, the BDNF long 3'UTR mRNA is increased in the hippocampal dentate granule cells (DGCs, leading to elevated expression of BDNF protein that is transported and stored in the mossy fiber (MF terminals. Our results identify HuD as the first trans-acting factor that enhances BDNF expression specifically through the long 3'UTR and a novel mechanism that regulates BDNF protein production in selected neuronal populations by HuD abundance.
Bagheri, Fatemeh; Mesrian Tanha, Hamzeh; Mojtabavi Naeini, Marjan; Ghaedi, Kamran; Azadeh, Mansoureh
ErbB4 can act as either a tumor-suppressor gene or an oncogene in breast cancer. Multiple genetic factors including single nucleotide polymorphisms (SNPs) affect gene expression patterns. Multiple 3'-untranslated region (3'-UTR) SNPs reside within the target binding site of microRNAs, which can strengthen or weaken binding to target genes. The present study aimed to predict potential 3'‑UTR variants of ErbB4 that alter the target binding site of microRNAs (miRNAs) and to clarify the association of the potential variant with the risk of developing breast cancer. In silico prediction was performed to identify potential functional SNPs within miRNA target binding sites in the 3'‑UTR of ErbB4. Thus, 146 patients and controls were genotyped using restriction fragment length polymorphism-polymerase chain reaction. In addition to the Cochran-Armitage test for trend, allele and genotype frequency differences were determined to investigate the association between rs1836724 and the susceptibility to breast cancer. Bioinformatics analysis identified rs1836724 to be a polymorphism in the seed region of four miRNA binding sites (hsa-miR335-5p, hsa-miR-28-5p, has‑miR‑708‑5p and has‑miR‑665), which may participate in the development of breast cancer. Logistic regression data indicated that the T allele of the polymorphism [OR (95% CI)=1.72 (1.056‑2.808), P=0.029] is associated with the risk of breast cancer. Using bioinformatics tools, a correlation was indicated between the presence of the T allele and a reduction in ErbB4 RNA silencing based on miRNA interaction. Furthermore, case subgroup data analysis revealed an association between the C/T genotype and an ER positive phenotype [OR (95% CI)=6.00 (1.082‑33.274), P=0.028] compared with the T/T genotype. ErbB4 and estrogen receptor 1 (ESR1) are regulated by identical miRNAs thus there may be a competition for binding sites. Due to this pattern, if the interaction between miRNAs with one gene is reduced, it
Ozturk, Onder; Basay, Burge Kabukcu; Buber, Ahmet; Basay, Omer; Alacam, Huseyin; Bacanlı, Ali; Yılmaz, Şenay Görücü; Erdal, Mehmet Emin; Ercan, Eyup Sabri
Objective Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that negatively affects different areas of life. We aimed to evaluate the associations between the Val66Met polymorphism of brain-derived neurotrophic factor (BDNF) and ADHD and to assess the effect of the BDNF polymorphism on the neurocognitive profile and clinical symptomatology in ADHD. Methods Two hundred one ADHD cases and 99 typically developing subjects (TD) between the ages of 8 and 15 years were involved in the study. All subjects were evaluated using a complete neuropsychological battery, Child Behavior Checklist, the Teacher's Report Form (TRF) and the DSM-IV Disruptive Behavior Disorders Rating Scale-teacher and parent forms. Results The GG genotype was significantly more frequent in the patients with ADHD than in the TD controls, and the GG genotype was also significantly more frequent in the ADHD-combined (ADHD-C) subtype patients than in the TDs. However, there were no significant associations of the BDNF polymorphism with the ADHD subtypes or neurocognitive profiles of the patients. The teacher-assessed hyperactivity and inattention symptom count and the total score were higher, and the appropriately behaving subtest score of the TRF was lower in the GG genotypes than in the GA and AA (i.e., the A-containing) genotypes. Conclusion We found a positive association between the BDNF gene Val66Met polymorphism and ADHD, and this association was observed specifically in the ADHD-C subtype and not the ADHD-predominantly inattentive subtype. Our findings support that the Val66Met polymorphism of BDNF gene might be involved in the pathogenesis of ADHD. Furthermore Val66Met polymorphism of BDNF gene may be more closely associated with hyperactivity rather than inattention.
Full Text Available Eugene Lin1,7, Po See Chen2,6,7, Lung-Cheng Huang3,4, Sen-Yen Hsu51Vita Genomics, Inc., Wugu Shiang, Taipei, Taiwan; 2Department of Psychiatry, Hospital and College of Medicine, National Cheng Kung University, Tainan, Taiwan; 3Department of Psychiatry, National Taiwan University Hospital Yun-Lin Branch, Taiwan; 4Graduate Institute of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; 5Department of Psychiatry, Chi Mei Medical Center, Liouying, Tainan, Taiwan; 6Department of Psychiatry, National Cheng Kung University Hospital, Dou-liou Branch, Yunlin, Taiwan; 7These authors contributed equally to this workAbstract: Major depressive disorder (MDD is one of the most common mental disorders worldwide. Single nucleotide polymorphisms (SNPs can be used in clinical association studies to determine the contribution of genes to drug efficacy. A common SNP in the brain-derived neurotrophic factor (BDNF gene, a methionine (Met substitution for valine (Val at codon 66 (Val66Met, is a candidate SNP for influencing antidepressant treatment outcome. In this study, our goal was to determine the relationship between the Val66Met polymorphism in the BDNF gene and the rapid antidepressant response to venlafaxine in a Taiwanese population with MDD. Overall, the BDNF Val66Met polymorphism was found not to be associated with short-term venlafaxine treatment outcome. However, the BDNF Val66Met polymorphism showed a trend to be associated with rapid venlafaxine treatment response in female patients. Future research with independent replication in large sample sizes is needed to confirm the role of the BDNF Val66Met polymorphism identified in this study.Keywords: antidepressant response, brain-derived neurotrophic factor, major depressive disorder, serotonin and norepinephrine reuptake inhibitor, single nucleotide polymorphisms
Hayakawa, Natsumi; Abe, Manami; Eto, Risa; Kato, Hiroyuki; Araki, Tsutomu
We investigated the age-related alterations in nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), parvalbumin and neuronal nitric oxide synthase (nNOS) immunoreactivity of the mouse hippocampal CA1 sector. NGF and BDNF immunoreactivity was unchanged in the hippocampal CA1 pyramidal neurons from 2 to 50-59 weeks of birth. In contrast, a significant increase in the NGF and BDNF immunoreactivity was observed in glial cells of the hippocampal CA1 sector from 40-42 to 50-59 weeks of birth. On the other hand, the number of parvalbumin- and nNOS-positive interneurons was unchanged in the hippocampal CA1 sector during aging processes, except for a significant decrease of nNOS-positive interneurons 2 weeks of birth. Our results indicate that NGF and BDNF immunoreactivity was unaltered in the hippocampal CA1 pyramidal neurons during aging processes. In contrast, a significant increase in the NGF and BDNF immunoreactivity was observed in glial cells of the hippocampal CA1 sector during aging processes. The present study also shows that the number of parvalbumin- and nNOS-positive interneurons was unchanged in the hippocampal CA1 sector during aging processes, except for a significant decrease of nNOS-positive interneurons 2 weeks of birth. These results demonstrate that the expression of glial NGF and BDNF may play a key role for helping survival and maintenance of pyramidal neurons and neuronal functions in the hippocampal CA1 sector during aging processes. Furthermore, our findings suggest that parvalbumin- and nNOS-positive interneurons in the hippocampal CA1 sector are resistant to aging processes. Moreover, our findings suggest that nitric oxide synthesized by the nNOS may play some role for neuronal growth during postnatal development.
Bianca Seifert; Robert Eckenstaler; Raik Rönicke; Julia Leschik; Beat Lutz; Klaus Reymann; Volkmar Lessmann; Tanja Brigadski
The neurotrophin brain derived neurotrophic factor (BDNF) is an important growth factor in the CNS. Deficits in transport of this secretory protein could underlie neurodegenerative diseases. Investigation of disease-related changes in BDNF transport might provide insights into the cellular mechanism underlying, for example, Alzheimer’s disease (AD). To analyze the role of BDNF transport in AD, live cell imaging of fluorescently labeled BDNF was performed in hippocampal neurons of different AD...
Sun, Min; Wang, Ke; Yu, Yan; Su, Wen-Ting; Jiang, Xin-Xin
Previous studies have identified the beneficial effects of electroacupuncture (EA) on motor behaviors in Parkinson's disease (PD). However, the role and potential mechanisms of EA in PD-associated depression remain unclear. In the present study, a rat model of PD with unilateral 6-hydroxydopamine (6-OHDA) lesions in the medial forebrain bundle was treated using EA for 4 weeks. We found that 100 Hz EA improved several motor phenotypes. In addition, tyrosine hydroxylase (TH) immunohistochemical analysis showed that EA had a minimal impact on the TH-positive profiles of the ipsilateral ventral tegmental area. Compared with the 6-OHDA group, long-term EA stimulation significantly increased sucrose solution consumption and decreased immobility time in the forced swim test. EA treatment did not alter dopamine, norepinephrine, and serotonin levels in the striatum and hippocampus. Noticeably, EA treatment reversed the 6-OHDA-induced abnormal expression of brain-derived neurotrophic factor (BDNF) and tropomyosin-related kinase B (TrkB) in the midbrain and hippocampus. These results demonstrate that EA at 100-Hz possesses the ability to improve depressive-like symptoms in PD rats, which is, at least in part, due to the distinct effect of EA on the mesostriatal and mesocorticolimbic dopaminergic pathways. Moreover, BDNF seems to participate in the effect of EA in PD. PMID:27525025
Chourbaji, Sabine; Brandwein, Christiane; Vogt, Miriam A; Dormann, Christof; Hellweg, Rainer; Gass, Peter
In earlier experiments we have demonstrated that group-housing in a rather impoverished "standard" environment can be a crucial stress factor in male C57Bl/6 mice. The present study aimed at investigating the effect of combining a probable genetic vulnerability--postulated by the "Neurotrophin Hypothesis of Depression"--with the potentially modulating influence of a stressful environment such as "impoverished" standard housing conditions. For that purpose mice with a partial deletion of brain-derived neurotrophic factor (BDNF) were group-housed under standard and enriched housing conditions and analysed in a well-established test battery for emotional behaviours. Standard group-housing affected emotional behaviour in male and female BDNF heterozygous mice, causing an increase in anxiety, changes in exploration as well as nociception. Providing the animals' cages with supplementary enrichment, however, led to a rescue of emotional alterations, which emphasises the significance of external factors and their relevance for a valid investigation of genetic aspects in these mutants as well as others, which may be examined in terms of stress-responsiveness or emotionality.
Wright, Tess; Gillespie, Lisa N; O'Leary, Stephen J; Needham, Karina
Primary auditory neurons rely on neurotrophic factors for development and survival. We previously determined that exposure to brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT3) alters the activity of hyperpolarization-activated currents (Ih) in this neuronal population. Since potassium channels are sensitive to neurotrophins, and changes in Ih are often accompanied by a shift in voltage-gated potassium currents (IK), this study examined IK with exposure to both BDNF and NT3 and the impact on firing entrainment during high frequency pulse trains. Whole-cell patch-clamp recordings revealed significant changes in action potential latency and duration, but no change in firing adaptation or total outward IK. Dendrotoxin-I (DTX-I), targeting voltage-gated potassium channel subunits KV1.1 and KV1.2, uncovered an increase in the contribution of DTX-I sensitive currents with exposure to neurotrophins. No difference in Phrixotoxin-1 (PaTX-1) sensitive currents, mediated by KV4.2 and KV4.3 subunits, was observed. Further, no difference was seen in firing entrainment. These results show that combined BDNF and NT3 exposure influences the contribution of KV1.1 and KV1.2 to the low voltage-activated potassium current (IKL). Whilst this is accompanied by a shift in spike latency and duration, both firing frequency and entrainment to high frequency pulse trains are preserved.
Zhang, Ji-Chun; Yao, Wei; Hashimoto, Kenji
Depression is the most prevalent and among the most debilitating of psychiatric disorders. The precise neurobiology of this illness is unknown. Several lines of evidence suggest that peripheral and central inflammation plays a role in depressive symptoms, and that anti-inflammatory drugs can improve depressive symptoms in patients with inflammation-related depression. Signaling via brain-derived neurotrophic factor (BDNF) and its receptor, tropomycin receptor kinase B (TrkB) plays a key role in the pathophysiology of depression and in the therapeutic mechanisms of antidepressants. A recent paper showed that lipopolysaccharide (LPS)-induced inflammation gave rise to depression-like phenotype by altering BDNF-TrkB signaling in the prefrontal cortex, hippocampus, and nucleus accumbens, areas thought to be involved in the antidepressant effects of TrkB agonist, 7,8-dihydroxyflavone (7,8-DHF) and TrkB antagonist, ANA-12. Here we provide an overview of the tryptophan-kynurenine pathway and BDNF-TrkB signaling in the pathophysiology of inflammation-induced depression, and propose mechanistic actions for potential therapeutic agents. Additionally, the authors discuss the putative role of TrkB agonists and antagonists as novel therapeutic drugs for inflammation-related depression.
Daws, L C; Munn, J L; Valdez, M F; Frosto-Burke, T; Hensler, J G
In the present study, we used high-speed chronoamperometry to examine serotonin (5-HT) transporter (5-HTT) function in vivo in 2-, 5-, and 10-month-old brain-derived neurotrophic factor (BDNF)+/- mice. The rate of clearance of exogenously applied 5-HT was measured in CA3 region of hippocampus. In 2-month-old mice, the rate of 5-HT clearance did not differ between BDNF+/+ and BDNF+/- mice. In BDNF+/+ mice, 5-HT clearance rate (Tc) increased markedly with age. In contrast, Tc remained relatively static in BDNF+/- mice across 2-, 5-, and 10-month age groups. At 5 months of age, female BDNF+/+ mice had a lower maximal velocity (Vmax) for 5-HT clearance than male BDNF+/+ mice. There was a similar trend in 5-month-old BDNF+/- mice, but this did not reach statistical significance. There was an age-dependent increase in KT value for 5-HT clearance (i.e., decreased in vivo affinity of 5-HTT), but no significant effect of genotype or gender. 5-HTT density, as measured by [3H]cyanoimipramine binding, was not different between BDNF+/+ and BDNF+/- mice, although there was a significant increase in 5-HTT binding with age. The selective 5-HT reuptake inhibitor fluvoxamine (50 and 100 pmol) significantly decreased 5-HT clearance in BDNF+/+ mice, but not in BDNF+/- mice. Our data suggest that the profoundly reduced ability of 5- and 10-month-old BDNF+/- mice to clear 5-HT is not because of a decrease in the total number of 5-HTTs, but may be due to functional deficits in the 5-HTT, e.g., in the machinery/signaling required for insertion of 5-HTTs into the plasma membrane and/or activation of the 5-HTT once it is positioned to take up 5-HT from extracellular fluid.
Sandra M. Garraway
Full Text Available Brain-derived neurotrophic factor (BDNF is a member of the neurotrophic factor family of signaling molecules. Since its discovery over three decades ago, BDNF has been identified as an important regulator of neuronal development, synaptic transmission, and cellular and synaptic plasticity and has been shown to function in the formation and maintenance of certain forms of memory. Neural plasticity that underlies learning and memory in the hippocampus shares distinct characteristics with spinal cord nociceptive plasticity. Research examining the role BDNF plays in spinal nociception and pain overwhelmingly suggests that BDNF promotes pronociceptive effects. BDNF induces synaptic facilitation and engages central sensitization-like mechanisms. Also, peripheral injury-induced neuropathic pain is often accompanied with increased spinal expression of BDNF. Research has extended to examine how spinal cord injury (SCI influences BDNF plasticity and the effects BDNF has on sensory and motor functions after SCI. Functional recovery and adaptive plasticity after SCI are typically associated with upregulation of BDNF. Although neuropathic pain is a common consequence of SCI, the relation between BDNF and pain after SCI remains elusive. This article reviews recent literature and discusses the diverse actions of BDNF. We also highlight similarities and differences in BDNF-induced nociceptive plasticity in naïve and SCI conditions.
Cattaneo, A; Cattane, N; Begni, V; Pariante, C M; Riva, M A
Brain-derived neurotrophic factor (BDNF) regulates the survival and growth of neurons, and influences synaptic efficiency and plasticity. The human BDNF gene consists of 11 exons, and distinct BDNF transcripts are produced through the use of alternative promoters and splicing events. The majority of the BDNF transcripts can be detected not only in the brain but also in the blood cells, although no study has yet investigated the differential expression of BDNF transcripts at the peripheral level. This review provides a description of the human BDNF gene structure as well as a summary of clinical and preclinical evidence supporting the role of BDNF in the pathogenesis of psychiatric disorders. We will discuss several mechanisms as possibly underlying BDNF modulation, including epigenetic mechanisms. We will also discuss the potential use of peripheral BDNF as a biomarker for psychiatric disorders, focusing on the factors that can influence BDNF gene expression and protein levels. Within this context, we have also characterized, for we believe the first time, the expression of BDNF transcripts in the blood, with the aim to provide novel insights into the molecular mechanisms and signaling that may regulate peripheral BDNF gene expression levels. PMID:27874848
Zunino, G; Messina, A; Sgadò, P; Baj, G; Casarosa, S; Bozzi, Y
Engrailed-2 (En2), a homeodomain transcription factor involved in regionalization and patterning of the midbrain and hindbrain regions has been associated to autism spectrum disorders (ASDs). En2 knockout (En2(-/-)) mice show ASD-like features accompanied by a significant loss of GABAergic subpopulations in the hippocampus and neocortex. Brain-derived neurotrophic factor (BDNF) is a crucial factor for the postnatal development of forebrain GABAergic neurons, and altered GABA signaling has been hypothesized to underlie the symptoms of ASD. Here we sought to determine whether interneuron loss in the En2(-/-) forebrain might be related to altered expression of BDNF and its signaling receptors. We first evaluated the expression of different BDNF mRNA isoforms in the neocortex and hippocampus of wild-type (WT) and En2(-/-) mice. Quantitative RT-PCR showed a marked down-regulation of several splicing variants of BDNF mRNA in the neocortex but not hippocampus of adult En2(-/-) mice, as compared to WT controls. Accordingly, levels of mature BDNF protein were lower in the neocortex but not hippocampus of En2(-/-) mice, as compared to WT. Increased levels of phosphorylated TrkB and decreased levels of p75 receptor were also detected in the neocortex of mutant mice. Accordingly, the expression of low density lipoprotein receptor (LDLR) and RhoA, two genes regulated via p75 was significantly altered in forebrain areas of mutant mice. These data indicate that BDNF signaling alterations might be involved in the anatomical changes observed in the En2(-/-) forebrain and suggest a pathogenic role of altered BDNF signaling in this mouse model of ASD.
Chaldakov, George N; Fiore, Marco; Stankulov, Ivan S; Manni, Luigi; Hristova, Mariyana G; Antonelli, Alessia; Ghenev, Peter I; Aloe, Luigi
The development of atherosclerotic cardiovascular disease is a common comorbidity in patients with the metabolic syndrome, a concurrence of cardiovascular risk factors in one individual. While multiple growth factors and adipokines are identified in atherosclerotic lesions, as well as neurotrophins implicated in both cardiac ischemia and lipid and glucose metabolism, the potential role of neurotrophins in human coronary atherosclerosis and in the metabolic syndrome still remains to be elucidated. Here we describe and discuss our results that represent a novel attempt to study the cardiovascular and metabolic biology of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and mast cells (MC). The local amount of NGF, the immunolocalization of p75 neurotrophin receptor (p75NTR) and the number of MC were correlatively examined in coronary vascular wall and in the surrounding subepicardial adipose tissue, obtained from autopsy cases in humans with advanced coronary atherosclerosis. We also analyzed the plasma levels of NGF, BDNF and leptin and the number of MC in biopsies from abdominal subcutaneous adipose tissue in patients with a severe form of the metabolic syndrome. The results demonstrate that NGF levels are decreased in atherosclerotic coronary vascular tissue but increased in the subepicardial adipose tissue, whereas both tissues express a greater number of MC and a stronger p75NTR immunoreactivity, compared to controls. Metabolic syndrome patients display a significant hyponeurotrophinemia and an increased number of adipose MC; the later correlates with elevated plasma leptin levels. In effect, we provide the first evidence for (i) an altered presence of NGF, p75NTR and MC in both coronary vascular and subepicardial adipose tissue in human coronary atherosclerosis, and (ii) a significant decrease in plasma NGF and BDNF levels and an elevated amount of plasma leptin and adipose MC in metabolic syndrome patients. Together our findings suggest that
Full Text Available Abstract Background Cell-specific expression of the gene that encodes brain-derived neurotrophic factor (BDNF is required for the normal development of peripheral sensory neurons and efficient synaptic transmission in the mature central and peripheral nervous system. The control of BDNF gene expression involves multiple tissue and cell-specific promoters that are differentially regulated. The molecular mechanisms that are responsible for tissue and cell-specific expression of these promoters are still incompletely understood. Results The cloning and analysis of three additional zebrafish (Danio rerio BDNF gene exons and two associated promoters, is reported. Among them are two exons that generate a novel tripartite mature transcript. The exons were located on the transcription unit, whose overall organization was determined by cloning, Southern blot hybridization and sequence analysis, and compared with the pufferfish (Fugu rubripes and mammalian BDNF loci, revealing a conserved but more compact organization. Structural and functional analysis of the exons, their adjacent promoters and 5' flanks, showed that they are expressed cell-specifically. The promoter associated with the 5' exon of the tripartite transcript is GC-rich, TATA-less and the 5' flank adjacent to it contains multiple Sp1, Mef2, and AP1 elements. A fusion gene containing the promoter and 1.5 KB of 5' flank is directed exclusively to skeletal muscle of transiently transfected embryos. The second promoter, whose associated 5' exon contains a 25-nucleotide segment of identity with a mammalian BDNF gene exon, was transiently expressed in yolk of the early embryo. RT-PCR analysis of total RNA from whole juvenile fish and adult female skeletal muscle revealed tissue-specific expression of the 5' exons but the novel exon could not be detected even after two rounds of nested PCR. Conclusion The zebrafish BDNF gene is as complex as the mammalian gene yet much more compact. Its exons are
Full Text Available In the mammalian brain, the neurotrophin brain-derived neurotrophic factor (BDNF has emerged as a key factor for synaptic refinement, plasticity and learning. Although BDNF-induced signaling cascades are well known, the spatial aspects of the synaptic BDNF localization remained unclear. Recent data provide strong evidence for an exclusive presynaptic location and anterograde secretion of endogenous BDNF at synapses of the hippocampal circuit. In contrast, various studies using BDNF overexpression in cultured hippocampal neurons support the idea that postsynaptic synapses and other dendritic structures are the preferential sites of BDNF localization and release. In this study we used rigorously tested anti-BDNF antibodies and achieved a dense labeling of endogenous BDNF close to synapses. Confocal microscopy showed natural BDNF close to many, but not all glutamatergic synapses, while neither GABAergic synapses nor postsynaptic structures carried a typical synaptic BDNF label. To visualize the BDNF distribution within the fine structure of synapses, we implemented super resolution fluorescence imaging by direct stochastic optical reconstruction microscopy (dSTORM. Two-color dSTORM images of neurites were acquired with a spatial resolution of ~20 nm. At this resolution, the synaptic scaffold proteins Bassoon and Homer exhibit hallmarks of mature synapses and form juxtaposed bars, separated by a synaptic cleft. BDNF imaging signals form granule-like clusters with a mean size of ~60 nm and are preferentially found within the fine structure of the glutamatergic presynapse. Individual glutamatergic presynapses carried up to 90% of the synaptic BDNF immunoreactivity, and only a minor fraction of BDNF molecules was found close to the postsynaptic bars. Our data proof that hippocampal neurons are able to enrich and store high amounts of BDNF in small granules within the mature glutamatergic presynapse, at a principle site of synaptic plasticity.
Hanno-Iijima, Yoko; Tanaka, Masami; Iijima, Takatoshi
Homeostatic synaptic plasticity, or synaptic scaling, is a mechanism that tunes neuronal transmission to compensate for prolonged, excessive changes in neuronal activity. Both excitatory and inhibitory neurons undergo homeostatic changes based on synaptic transmission strength, which could effectively contribute to a fine-tuning of circuit activity. However, gene regulation that underlies homeostatic synaptic plasticity in GABAergic (GABA, gamma aminobutyric) neurons is still poorly understood. The present study demonstrated activity-dependent dynamic scaling in which NMDA-R (N-methyl-D-aspartic acid receptor) activity regulated the expression of GABA synthetic enzymes: glutamic acid decarboxylase 65 and 67 (GAD65 and GAD67). Results revealed that activity-regulated BDNF (brain-derived neurotrophic factor) release is necessary, but not sufficient, for activity-dependent up-scaling of these GAD isoforms. Bidirectional forms of activity-dependent GAD expression require both BDNF-dependent and BDNF-independent pathways, both triggered by NMDA-R activity. Additional results indicated that these two GAD genes differ in their responsiveness to chronic changes in neuronal activity, which could be partially caused by differential dependence on BDNF. In parallel to activity-dependent bidirectional scaling in GAD expression, the present study further observed that a chronic change in neuronal activity leads to an alteration in neurotransmitter release from GABAergic neurons in a homeostatic, bidirectional fashion. Therefore, the differential expression of GAD65 and 67 during prolonged changes in neuronal activity may be implicated in some aspects of bidirectional homeostatic plasticity within mature GABAergic presynapses.
Hill, Kathryn T; Warren, Megan; Roth, Tania L
Previous work with various animal models has demonstrated that alterations in the caregiving environment produce long-term changes in anxiety-related and social behaviors, as well as amygdala gene expression. We previously introduced a rodent model in which the timing and duration of exposure to maltreatment or nurturing care outside the home cage can be controlled to assess neurobiological outcomes. Here we sought to determine whether our brief experimental conditions produce changes in gene expression within the developing and adult amygdala. Using a candidate gene approach, we examined fold mRNA changes for the Brain-derived neurotrophic factor (Bdnf), Oxytocin receptor (OXTr), and Neuropeptide Y (NPY) genes, which are all highly expressed in the amygdala and play important roles in anxiety-related and social behaviors. In adults, significant group differences were detected for only Bdnf, with higher levels of Bdnf mRNA for females that had been exposed to maltreatment and males exposed to nurturing care outside the home cage relative to littermate controls. For pups, significant group differences were detected for only OXTr, with lower levels of OXTr mRNA in females exposed to maltreatment. Finally, for adolescents, maltreated-females showed significant changes in Bdnf (decreased), OXTr (decreased), and NPY (increased) mRNA relative to controls. These data illustrate the ability of brief, but repeated exposure to different caregiving environments during the first postnatal week to have long-term effects on gene expression within the developing and adult amygdala, especially for females.
Sérgio Gomes da Silva
Full Text Available Clinical evidence has shown that physical exercise during pregnancy may alter brain development and improve cognitive function of offspring. However, the mechanisms through which maternal exercise might promote such effects are not well understood. The present study examined levels of brain-derived neurotrophic factor (BDNF and absolute cell numbers in the hippocampal formation and cerebral cortex of rat pups born from mothers exercised during pregnancy. Additionally, we evaluated the cognitive abilities of adult offspring in different behavioral paradigms (exploratory activity and habituation in open field tests, spatial memory in a water maze test, and aversive memory in a step-down inhibitory avoidance task. Results showed that maternal exercise during pregnancy increased BDNF levels and absolute numbers of neuronal and non-neuronal cells in the hippocampal formation of offspring. No differences in BDNF levels or cell numbers were detected in the cerebral cortex. It was also observed that offspring from exercised mothers exhibited better cognitive performance in nonassociative (habituation and associative (spatial learning mnemonic tasks than did offspring from sedentary mothers. Our findings indicate that maternal exercise during pregnancy enhances offspring cognitive function (habituation behavior and spatial learning and increases BDNF levels and cell numbers in the hippocampal formation of offspring.
Dagnino-Subiabre, Alexies; Zepeda-Carreño, Rodrigo; Díaz-Véliz, Gabriela; Mora, Sergio; Aboitiz, Francisco
Chronic stress affects brain areas involved in learning and emotional responses. These alterations have been related with the development of cognitive deficits in major depression. Moreover, stress induces deleterious actions on the epithalamic pineal organ, a gland involved in a wide range of physiological functions. The aim of this study was to investigate whether the stress effects on the pineal gland are related with changes in the expression of neurotrophic factors and cell adhesion molecules. Using reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, we analyzed the effect of chronic immobilization stress on the BDNF mRNA and integrin alpha5 expression in the rat pineal gland. We found that BDNF is produced in situ in the pineal gland. Chronic immobilization stress induced upregulation of BDNF mRNA and integrin alpha5 expression in the rat pineal gland but did not produce changes in beta-actin mRNA or in GAPDH expression. Stressed animals also evidenced an increase in anxiety-like behavior and acute gastric lesions. These results suggest that BDNF and integrin alpha5 may have a counteracting effect to the deleterious actions of immobilization stress on functionally stimulated pinealocytes. Furthermore, this study proposes that the pineal gland may be a target of glucocorticoid damage during stress.
Chapleau, Christopher A; Larimore, Jennifer L; Theibert, Anne; Pozzo-Miller, Lucas
The process of axonal and dendritic development establishes the synaptic circuitry of the central nervous system (CNS) and is the result of interactions between intrinsic molecular factors and the external environment. One growth factor that has a compelling function in neuronal development is the neurotrophin brain-derived neurotrophic factor (BDNF). BDNF participates in axonal and dendritic differentiation during embryonic stages of neuronal development, as well as in the formation and maturation of dendritic spines during postnatal development. Recent studies have also implicated vesicular trafficking of BDNF via secretory vesicles, and both secretory and endosomal trafficking of vesicles containing synaptic proteins, such as neurotransmitter and neurotrophin receptors, in the regulation of axonal and dendritic differentiation, and in dendritic spine morphogenesis. Several genes that are either mutated or deregulated in neurodevelopmental disorders associated with mental retardation have now been identified, and several mouse models of these disorders have been generated and characterized. Interestingly, abnormalities in dendritic and synaptic structure are consistently observed in human neurodevelopmental disorders associated with mental retardation, and in mouse models of these disorders as well. Abnormalities in dendritic and synaptic differentiation are thought to underlie altered synaptic function and network connectivity, thus contributing to the clinical outcome. Here, we review the roles of BDNF and vesicular trafficking in axonal and dendritic differentiation in the context of dendritic and axonal morphological impairments commonly observed in neurodevelopmental disorders associated with mental retardation.
Seong-Jin Yu; Kuan-Yin Tseng; Hui Shen; Harvey, Brandon K.; Mikko Airavaara; Yun Wang
Migration of new neuroprogenitor cells (NPCs) from the subventricular zone (SVZ) plays an important role in neurorepair after injury. Previous studies have shown that brain derived neurotrophic factor (BDNF) enhances the migration of NPCs from SVZ explants in neonatal mice in vitro. The purpose of this study was to identify the role of BDNF in SVZ cells using AAV-BDNF in an animal model of stroke. BDNF protein production after AAV-BDNF infection was verified in primary neuronal culture. AAV-B...
Baj, Gabriele; D'Alessandro, Valentina; Musazzi, Laura; Mallei, Alessandra; Sartori, Cesar R; Sciancalepore, Marina; Tardito, Daniela; Langone, Francesco; Popoli, Maurizio; Tongiorgi, Enrico
Brain-derived neurotrophic factor (BDNF) is encoded by multiple BDNF transcripts, whose function is unclear. We recently showed that a subset of BDNF transcripts can traffic into distal dendrites in response to electrical activity, while others are segregated into the somatoproximal domains. Physical exercise and antidepressant treatments exert their beneficial effects through upregulation of BDNF, which is required to support survival and differentiation of newborn dentate gyrus (DG) neurons. While these DG processes are required for the antidepressant effect, a role for CA1 in antidepressant action has been excluded, and the effect on CA3 neurons remains unclear. Here, we show for the first time that physical exercise and antidepressants induce local increase of BDNF in CA3. Voluntary physical exercise for 28 consecutive days, or 2-week treatment with 10 mg/kg per day fluoxetine or reboxetine, produced a global increase of BDNF mRNA and protein in the neuronal somata of the whole hippocampus and a specific increase of BDNF in dendrites of CA3 neurons. This increase was accounted for by BDNF exon 6 variant. In cultured hippocampal neurons, application of serotonin or norepinephrine (10-50 μM) induced increase in synaptic transmission and targeting of BDNF mRNA in dendrites. The increased expression of BDNF in CA3 dendrites following antidepressants or exercise further supports the neurotrophin hypothesis of antidepressants action and confirms that the differential subcellular localization of BDNF mRNA splice variants provides a spatial code for a selective expression of BDNF in specific subcellular districts. This selective expression may be exploited to design more specific antidepressants.
Takahashi, Makoto; Ishikawa, Kinya; Sato, Nozomu; Obayashi, Masato; Niimi, Yusuke; Ishiguro, Taro; Yamada, Mitsunori; Toyoshima, Yasuko; Takahashi, Hitoshi; Kato, Takeo; Takao, Masaki; Murayama, Shigeo; Mori, Osamu; Eishi, Yoshinobu; Mizusawa, Hidehiro
Spinocerebellar ataxia type 6 (SCA6) is an autosomal-dominant neurodegenerative disorder caused by a small expansion of tri-nucleotide (CAG) repeat encoding polyglutamine (polyQ) in the gene for α(1A) voltage-dependent calcium channel (Ca(v) 2.1). Thus, this disease is one of the nine neurodegenerative disorders called polyQ diseases. The Purkinje cell predominant neuronal loss is the characteristic neuropathology of SCA6, and a 75-kDa carboxy-terminal fragment (CTF) of Ca(v) 2.1 containing polyQ, which remains soluble in normal brains, becomes insoluble in the cytoplasm of SCA6 Purkinje cells. Because the suppression of the brain-derived neurotrophic factor (BDNF) expression is a potentially momentous phenomenon in many other polyQ diseases, we implemented BDNF expression analysis in SCA6 human cerebellum using quantitative RT-PCR for the BDNF mRNA, and by immunohistochemistry for the BDNF protein. We observed significantly reduced BDNF mRNA levels in SCA6 cerebellum (n = 3) compared to controls (n = 6) (Mann-Whitney U-test, P = 0.0201). On immunohistochemistry, BDNF protein was only weakly stained in control cerebellum. On the other hand, we found numerous BDNF-immunoreactive granules in dendrites of SCA6 Purkinje cells. We did not observe similar BDNF-immunoreactive granules in other polyQ diseases, such as Huntington's disease or SCA2. As we often observed that the 1C2-positive Ca(v) 2.1 aggregates existed more proximally than the BDNF-positive granules in the dendrites, we speculated that the BDNF protein trafficking in dendrites may be disturbed by Ca(v) 2.1 aggregates in SCA6 Purkinje cells. We conclude that the SCA6 pathogenic mechanism associates with the BDNF mRNA expression reduction and abnormal localization of BDNF protein.
Full Text Available Migration of new neuroprogenitor cells (NPCs from the subventricular zone (SVZ plays an important role in neurorepair after injury. Previous studies have shown that brain derived neurotrophic factor (BDNF enhances the migration of NPCs from SVZ explants in neonatal mice in vitro. The purpose of this study was to identify the role of BDNF in SVZ cells using AAV-BDNF in an animal model of stroke. BDNF protein production after AAV-BDNF infection was verified in primary neuronal culture. AAV-BDNF or AAV-RFP was injected into the left SVZ region of adult rats at 14 days prior to right middle cerebral artery occlusion (MCAo. SVZ tissues were collected from the brain and placed in Metrigel cultures 1 day after MCAo. Treatment with AAV-BDNF significantly increased the migration of SVZ cells in the stroke brain in vitro. In another set of animals, AAV-GFP was co-injected with AAV-BDNF or AAV-RFP to label cells in left SVZ prior to right MCAo. Local administration of AAV-BDNF significantly enhanced recovery of locomotor function and migration of GFP-positive cells from the SVZ toward the lesioned hemisphere in stroke rats. Our data suggest that focal administration of AAV-BDNF to the SVZ increases behavioral recovery post stroke, possibly through the enhancement of migration of cells from SVZ in stroke animals. Regional manipulation of BDNF expression through AAV may be a novel approach for neurorepair in stroke brains.
Yu, Seong-Jin; Tseng, Kuan-Yin; Shen, Hui; Harvey, Brandon K; Airavaara, Mikko; Wang, Yun
Migration of new neuroprogenitor cells (NPCs) from the subventricular zone (SVZ) plays an important role in neurorepair after injury. Previous studies have shown that brain derived neurotrophic factor (BDNF) enhances the migration of NPCs from SVZ explants in neonatal mice in vitro. The purpose of this study was to identify the role of BDNF in SVZ cells using AAV-BDNF in an animal model of stroke. BDNF protein production after AAV-BDNF infection was verified in primary neuronal culture. AAV-BDNF or AAV-RFP was injected into the left SVZ region of adult rats at 14 days prior to right middle cerebral artery occlusion (MCAo). SVZ tissues were collected from the brain and placed in Metrigel cultures 1 day after MCAo. Treatment with AAV-BDNF significantly increased the migration of SVZ cells in the stroke brain in vitro. In another set of animals, AAV-GFP was co-injected with AAV-BDNF or AAV-RFP to label cells in left SVZ prior to right MCAo. Local administration of AAV-BDNF significantly enhanced recovery of locomotor function and migration of GFP-positive cells from the SVZ toward the lesioned hemisphere in stroke rats. Our data suggest that focal administration of AAV-BDNF to the SVZ increases behavioral recovery post stroke, possibly through the enhancement of migration of cells from SVZ in stroke animals. Regional manipulation of BDNF expression through AAV may be a novel approach for neurorepair in stroke brains.
Full Text Available Abstract Background Recent rodent studies reported that antidepressant treatments affect the expression of brain-derived neurotrophic factor (BDNF mRNA in a way that is dependent on treatment duration, by selective modulation of different BDNF transcripts. However, no data are available for the human BDNF gene. We studied the effect of different antidepressants on BDNF mRNA expression in human neuroblastoma SH-SY5Y cells. Results Cultured cells were treated with the antidepressants fluoxetine, reboxetine and desipramine for different time lengths (6, 24, 48 hours. Expression of total BDNF mRNA was analyzed by reverse transcription PCR and levels of different BDNF transcripts were detected by hemi-nested PCR with specific primers. Short-term treatment (6 hours with reboxetine or desipramine reduced total BDNF, whereas long-term treatment (48 hours significantly increased total BDNF mRNA levels. These changes were accounted for by differential regulation of BDNF IV and VIa/b transcripts. Fluoxetine showed no significant effects. Conclusion This is the first study showing biphasic changes in the expression of total and specific BDNF transcripts in human cells following antidepressant treatments. These findings suggest that biphasic induction of BDNF by antidepressants could be a feature common to rodents and humans and encourage the use of SH-SY5Y cells as a tool for investigation of drug effects on human genes.
Chan, Adeline; Yan, Jun; Csurhes, Peter; Greer, Judith; McCombe, Pamela
The aim of this study was to measure the levels of circulating BDNF and the frequency of BDNF-producing T cells after acute ischaemic stroke. Serum BDNF levels were measured by ELISA. Flow cytometry was used to enumerate peripheral blood leukocytes that were labelled with antibodies against markers of T cells, T regulatory cells (Tregs), and intracellular BDNF. There was a slight increase in serum BDNF levels after stroke. There was no overall difference between stroke patients and controls in the frequency of CD4(+) and CD8(+) BDNF(+) cells, although a subgroup of stroke patients showed high frequencies of these cells. However, there was an increase in the percentage of BDNF(+) Treg cells in the CD4(+) population in stroke patients compared to controls. Patients with high percentages of CD4(+) BDNF(+) Treg cells had a better outcome at 6months than those with lower levels. These groups did not differ in age, gender or initial stroke severity. Enhancement of BDNF production after stroke could be a useful means of improving neuroprotection and recovery after stroke.
Der neurotrophe Faktor BDNF steht im Verdacht, läsionsinduzierte Plastizität zu beeinflussen. Durch elektrophysiologische Versuche konnte in Wt Kontrolltieren eine 20%ige LTP beobachtet werden, während BDNF(+/-) Mäuse keine LTP ausbildeten. Nach Läsionen zeigten Wt Tiere eine erhöhte LTP von ca. 40%. Bei BDNF(+/-) Mäusen post-Läsion wurde ebenfalls eine stabile LTP von etwas mehr als 20% gemessen. Zudem zeigten BDNF(+/-) Tieren wie auch in Wt Tieren 24h nach Läsion eine signifikan...
Harlow, Danielle E; Yang, Hui; Williams, Trevor; Barlow, Linda A
In mice, BDNF provided by the developing taste epithelium is required for gustatory neuron survival following target innervation. However, we find that expression of BDNF, as detected by BDNF-driven β-galactosidase, begins in the cranial ganglia before its expression in the central (hindbrain) or peripheral (taste papillae) targets of these sensory neurons, and before gustatory ganglion cells innervate either target. To test early BDNF function, we examined the ganglia of bdnf null mice before target innervation, and found that while initial neuron survival is unaltered, early neuron development is disrupted. In addition, fate mapping analysis in mice demonstrates that murine cranial ganglia arise from two embryonic populations, i.e., epibranchial placodes and neural crest, as has been described for these ganglia in non-mammalian vertebrates. Only placodal neurons produce BDNF, however, which indicates that prior to innervation, early ganglionic BDNF produced by placode-derived cells promotes gustatory neuron development.
SCHARFMAN, HELEN E.; MacLusky, Neil J.
Many studies have described potent effects of BDNF, 17β-estradiol or androgen on hippocampal synapses and their plasticity. Far less information is available about the interactions between 17β-estradiol and BDNF in hippocampus, or interactions between androgen and BDNF in hippocampus. Here we review the regulation of BDNF in the mossy fiber pathway, a critical part of hippocampal circuitry. We discuss the emerging view that 17β-estradiol upregulates mossy fiber BDNF synthesis in the adult fem...
Full Text Available Physical exercise constitutes an innovative strategy to treat deficits associated with stroke through the promotion of BDNF-dependent neuroplasticity. However, there is no consensus on the optimal intensity/duration of exercise. In addition, whether previous stroke changes the effect of exercise on the brain is not known. Therefore, the present study compared the effects of a clinically-relevant form of exercise on cerebral BDNF levels and localization in control versus stroke rats. For this purpose, treadmill exercise (0.3 m/s, 30 min/day, for 7 consecutive days was started in rats with a cortical ischemic stroke after complete maturation of the lesion or in control rats. Sedentary rats were run in parallel. Mature and proBDNF levels were measured on the day following the last boot of exercise using Western blotting analysis. Total BDNF levels were simultaneously measured using ELISA tests. As compared to the striatum and the hippocampus, the cortex was the most responsive region to exercise. In this region, exercise resulted in a comparable increase in the production of mature BDNF in intact and stroke rats but increased proBDNF levels only in intact rats. Importantly, levels of mature BDNF and synaptophysin were strongly correlated. These changes in BDNF metabolism coincided with the appearance of intense BDNF labeling in the endothelium of cortical vessels. Notably, ELISA tests failed to detect changes in BDNF forms. Our results suggest that control beings can be used to find conditions of exercise that will result in increased mBDNF levels in stroke beings. They also suggest cerebral endothelium as a potential source of BDNF after exercise and highlight the importance to specifically measure the mature form of BDNF to assess BDNF-dependent plasticity in relation with exercise.
Hill, Rachel A; Klug, Maren; Kiss Von Soly, Szerenke; Binder, Michele D; Hannan, Anthony J; van den Buuse, Maarten
Post-mortem studies have demonstrated reduced expression of brain-derived neurotrophic factor (BDNF) in the hippocampus of schizophrenia and major depression patients. The "two hit" hypothesis proposes that two or more major disruptions at specific time points during development are involved in the pathophysiology of these mental illnesses. However, the role of BDNF in these "two hit" effects is unclear. Our aim was to behaviorally characterize a "two hit" rat model of developmental stress accompanied by an in-depth assessment of BDNF expression and signalling. Wistar rats were exposed to neonatal maternal separation (MS) stress and/or adolescent/young-adult corticosterone (CORT) treatment. In adulthood, models of cognitive and negative symptoms of mental illness were analyzed. The hippocampus was then dissected into dorsal (DHP) and ventral (VHP) regions and analyzed by qPCR for exon-specific BDNF gene expression or by Western blot for BDNF protein expression and downstream signaling. Male "two hit" rats showed marked disruptions in short-term spatial memory (Y-maze) which were absent in females. However, female "two hit" rats showed signs of anhedonia (sucrose preference test), which were absent in males. Novel object recognition and anxiety (elevated plus maze) were unchanged by either of the two "hits". In the DHP, MS caused a male-specific increase in BDNF Exons I, II, IV, VII, and IX mRNA but a decrease in mature BDNF and phosphorylated TrkB (pTrkB) protein expression in adulthood. In the VHP, BDNF transcript expression was unchanged; however, in female rats only, MS significantly decreased mature BDNF and pTrkB protein expression in adulthood. These data demonstrate that MS causes region-specific and sex-specific long-term effects on BDNF expression and signaling and, importantly, mRNA expression does not always infer protein expression. Alterations to BDNF signaling may mediate the sex-specific effects of developmental stress on anhedonic behaviors.
McCarson Kenneth E
Full Text Available Abstract Persistent pain produces complex alterations in sensory pathways of the central nervous system (CNS through activation of various nociceptive mechanisms. However, the effects of pain on higher brain centers, particularly the influence of the stressful component of pain on the limbic system, are poorly understood. Neurokinin-1 (NK-1 receptors and brain-derived neurotrophic factor (BDNF, known neuromediators of hyperalgesia and spinal central sensitization, have also been implicated in the plasticity and neurodegeneration occurring in the hippocampal formation during exposures to various stressors. Results of this study showed that injections of complete Freund's adjuvant (CFA into the hind paw increased NK-1 receptor and BDNF mRNA levels in the ipsilateral dorsal horn, supporting an important role for these nociceptive mediators in the amplification of ascending pain signaling. An opposite effect was observed in the hippocampus, where CFA down-regulated NK-1 receptor and BDNF gene expression, phenomena previously observed in immobilization models of stress and depression. Western blot analyses demonstrated that in the spinal cord, CFA also increased levels of phosphorylated cAMP response element-binding protein (CREB, while in the hippocampus the activation of this transcription factor was significantly reduced, further suggesting that tissue specific transcription of either NK-1 or BDNF genes may be partially regulated by common intracellular transduction mechanisms mediated through activation of CREB. These findings suggest that persistent nociception induces differential regional regulation of NK-1 receptor and BDNF gene expression and CREB activation in the CNS, potentially reflecting varied roles of these neuromodulators in the spinal cord during persistent sensory activation vs. modulation of the higher brain structures such as the hippocampus.
Duric, Vanja; McCarson, Kenneth E
Persistent pain produces complex alterations in sensory pathways of the central nervous system (CNS) through activation of various nociceptive mechanisms. However, the effects of pain on higher brain centers, particularly the influence of the stressful component of pain on the limbic system, are poorly understood. Neurokinin-1 (NK-1) receptors and brain-derived neurotrophic factor (BDNF), known neuromediators of hyperalgesia and spinal central sensitization, have also been implicated in the plasticity and neurodegeneration occurring in the hippocampal formation during exposures to various stressors. Results of this study showed that injections of complete Freund's adjuvant (CFA) into the hind paw increased NK-1 receptor and BDNF mRNA levels in the ipsilateral dorsal horn, supporting an important role for these nociceptive mediators in the amplification of ascending pain signaling. An opposite effect was observed in the hippocampus, where CFA down-regulated NK-1 receptor and BDNF gene expression, phenomena previously observed in immobilization models of stress and depression. Western blot analyses demonstrated that in the spinal cord, CFA also increased levels of phosphorylated cAMP response element-binding protein (CREB), while in the hippocampus the activation of this transcription factor was significantly reduced, further suggesting that tissue specific transcription of either NK-1 or BDNF genes may be partially regulated by common intracellular transduction mechanisms mediated through activation of CREB. These findings suggest that persistent nociception induces differential regional regulation of NK-1 receptor and BDNF gene expression and CREB activation in the CNS, potentially reflecting varied roles of these neuromodulators in the spinal cord during persistent sensory activation vs. modulation of the higher brain structures such as the hippocampus.
Tejeda, Gonzalo S; Ayuso-Dolado, Sara; Arbeteta, Raquel; Esteban-Ortega, Gema M; Vidaurre, Oscar G; Díaz-Guerra, Margarita
Stroke remains a leading cause of death and disability in the world with limited therapies available to restrict brain damage or improve functional recovery after cerebral ischaemia. A promising strategy currently under investigation is the promotion of brain-derived neurotrophic factor (BDNF) signalling through tropomyosin-related kinase B (TrkB) receptors, a pathway essential for neuronal survival and function. However, TrkB and BDNF-signalling are impaired by excitotoxicity, a primary pathological process in stroke also associated with neurodegenerative diseases. Pathological imbalance of TrkB isoforms is critical in neurodegeneration and is caused by calpain processing of BDNF high affinity full-length receptor (TrkB-FL) and an inversion of the transcriptional pattern of the Ntrk2 gene, to favour expression of the truncated isoform TrkB-T1 over TrkB-FL. We report here that both TrkB-FL and neuronal TrkB-T1 also undergo ectodomain shedding by metalloproteinases activated after ischaemic injury or excitotoxic damage of cortical neurons. Subsequently, the remaining membrane-bound C-terminal fragments (CTFs) are cleaved by γ-secretases within the transmembrane region, releasing their intracellular domains (ICDs) into the cytosol. Therefore, we identify TrkB-FL and TrkB-T1 as new substrates of regulated intramembrane proteolysis (RIP), a mechanism that highly contributes to TrkB-T1 regulation in ischaemia but is minor for TrkB-FL which is mainly processed by calpain. However, since the secreted TrkB ectodomain acts as a BDNF scavenger and significantly alters BDNF/TrkB signalling, the mechanism of RIP could contribute to neuronal death in excitotoxicity. These results are highly relevant since they reveal new targets for the rational design of therapies to treat stroke and other pathologies with an excitotoxic component.
Kumari, Anita; Singh, Padmanabh; Baghel, Meghraj Singh; Thakur, M K
Adverse early life experience is prominent risk factors for numerous psychiatric illnesses, including mood and anxiety disorders. It imposes serious long-term costs on the individual as well as health and social systems. Hence, developing therapies that prevent the long-term consequences of early life stress is of utmost importance, and necessitates a better understanding of the mechanisms by which early life stress triggers long-lasting alterations in gene expression and behavior. Post-weaning isolation rearing of rodents models the behavioral consequences of adverse early life experiences in humans and it is reported to cause anxiety like behavior which is more common in case of females. Therefore, in the present study, we have studied the impact of social isolation of young female mice for 8weeks on the anxiety like behavior and the underlying molecular mechanism. Elevated plus maze and open field test revealed that social isolation caused anxiety like behavior. BDNF, a well-known molecule implicated in the anxiety like behavior, was up-regulated both at the message and protein level in cerebral cortex by social isolation. CREB-1 and CBP, which play a crucial role in BDNF transcription, were up-regulated at mRNA level in cerebral cortex by social isolation. HDAC-2, which negatively regulates BDNF expression, was down-regulated at mRNA and protein level in cerebral cortex by social isolation. Furthermore, BDNF acts in concert with Limk-1, miRNA-132 and miRNA-134 for the regulation of structural and morphological plasticity. Social isolation resulted in up-regulation of Limk-1 mRNA and miRNA-132 expression in the cerebral cortex. MiRNA-134, which inhibits the translation of Limk-1, was decreased in cerebral cortex by social isolation. Taken together, our study suggests that social isolation mediated anxiety like behavior is associated with up-regulation of BDNF expression and concomitant increase in the expression of CBP, CREB-1, Limk-1 and miRNA-132, and decrease
Jha, S; Dong, B E; Xue, Y; Delotterie, D F; Vail, M G; Sakata, K
Reduced promoter IV-driven expression of brain-derived neurotrophic factor (BDNF) is implicated in stress and major depression. We previously reported that defective promoter IV (KIV) caused depression-like behavior in young adult mice, which was reversed more effectively by enriched environment treatment (EET) than antidepressants. The effects of promoter IV-BDNF deficiency and EET over the life stages remain unknown. Since early-life development (ED) involves dynamic epigenetic processes, we hypothesized that EET during ED would provide maximum antidepressive effects that would persist later in life due to enhanced, long-lasting BDNF induction. We tested this hypothesis by determining EET effects across three life stages: ED (0–2 months), young adult (2–4 months), and old adult (12–14 months). KIV mice at all life stages showed depression-like behavior in the open-field and tail-suspension tests compared with wild-type mice. Two months of EET reduced depression-like behavior in ED and young adult, but not old adult mice, with the largest effect in ED KIV mice. This effect lasted for 1 month after discontinuance of EET only in ED mice. BDNF protein induction by EET in the hippocampus and frontal cortex was also the largest in ED mice and persisted only in the hippocampus of ED KIV mice after discontinuance of EET. No gender-specific effects were observed. The results suggest that defective promoter IV causes depression-like behavior, regardless of age and gender, and that EET during ED is particularly beneficial to individuals with promoter IV-BDNF deficiency, while additional treatment may be needed for older adults. PMID:27648918
Waterhouse, Emily G; An, Juan Ji; Orefice, Lauren L; Baydyuk, Maryna; Liao, Guey-Ying; Zheng, Kang; Lu, Bai; Xu, Baoji
Brain-derived neurotrophic factor (BDNF) has been implicated in regulating adult neurogenesis in the subgranular zone (SGZ) of the dentate gyrus; however, the mechanism underlying this regulation remains unclear. In this study, we found that Bdnf mRNA localized to distal dendrites of dentate gyrus granule cells isolated from wild-type (WT) mice, but not from Bdnf(klox/klox) mice where the long 3' untranslated region (UTR) of Bdnf mRNA is truncated. KCl-induced membrane depolarization stimulated release of dendritic BDNF translated from long 3' UTR Bdnf mRNA in cultured hippocampal neurons, but not from short 3' UTR Bdnf mRNA. Bdnf(klox/klox) mice exhibited reduced expression of glutamic acid decarboxylase 65 (a GABA synthase), increased proliferation of progenitor cells, and impaired differentiation and maturation of newborn neurons in the SGZ. These deficits in adult neurogenesis were rescued with administration of phenobarbital, an enhancer of GABA(A) receptor activity. Furthermore, we observed similar neurogenesis deficits in mice where the receptor for BDNF, TrkB, was selectively abolished in parvalbumin (PV)-expressing GABAergic interneurons. Thus, our data suggest that locally synthesized BDNF in dendrites of granule cells promotes differentiation and maturation of progenitor cells in the SGZ by enhancing GABA release, at least in part, from PV-expressing GABAergic interneurons.
Polacchini, Alessio; Albani, Clara; Baj, Gabriele; Colliva, Andrea; Carpinelli, Patrizia; Tongiorgi, Enrico
Drug-resistance to chemotherapics in aggressive neuroblastoma (NB) is characterized by enhanced cell survival mediated by TrkB and its ligand, brain-derived neurotrophic factor (BDNF); thus reduction in BDNF levels represent a promising strategy to overcome drug-resistance, but how chemotherapics regulate BDNF is unknown. Here, cisplatin treatment in SK-N-BE neuroblastoma upregulated multiple BDNF transcripts, except exons 5 and 8 variants. Cisplatin increased BDNF mRNA and protein, and enhanced translation of a firefly reporter gene flanked by BDNF 5'UTR exons 1, 2c, 4 or 6 and 3'UTR-long. To block BDNF translation we focused on aurora kinases inhibitors which are proposed as new chemotherapeutics. NB cell survival after 24 h treatment was 43% with cisplatin, and 22% by cisplatin+aurora kinase inhibitor PHA-680632, while the aurora kinases inhibitor alone was less effective; however the combined treatment induced a paradoxical increase of BDNF in surviving cells with strong translational activation of exon6-3'UTR-long transcript, while translation of BDNF transcripts 1, 2C and 4 was suppressed. In conclusion, combined cisplatin and aurora kinase inhibitor treatment increases cell death, but induces BDNF overproduction in surviving cells through an aurora kinase-independent mechanism.
Maria del Carmen Cardenas-Aguayo
Full Text Available The level of brain-derived neurotrophic factor (BDNF, a member of the neurotrophin family, is down regulated in Alzheimer's disease (AD, Parkinson's disease (PD, depression, stress, and anxiety; conversely the level of this neurotrophin is increased in autism spectrum disorders. Thus, modulating the level of BDNF can be a potential therapeutic approach for nervous system pathologies. In the present study, we designed five different tetra peptides (peptides B-1 to B-5 corresponding to different active regions of BDNF. These tetra peptides were found to be non-toxic, and they induced the expression of neuronal markers in mouse embryonic day 18 (E18 primary hippocampal neuronal cultures. Additionally, peptide B-5 induced the expression of BDNF and its receptor, TrkB, suggesting a positive feedback mechanism. The BDNF peptides induced only a moderate activation (phosphorylation at Tyr 706 of the TrkB receptor, which could be blocked by the Trk's inhibitor, K252a. Peptide B-3, when combined with BDNF, potentiated the survival effect of this neurotrophin on H(2O(2-treated E18 hippocampal cells. Peptides B-3 and B-5 were found to work as partial agonists and as partial antagonists competing with BDNF to activate the TrkB receptor in a dose-dependent manner. Taken together, these results suggest that the described BDNF tetra peptides are neurotrophic, can modulate BDNF signaling in a partial agonist/antagonist way, and offer a novel therapeutic approach to neural pathologies where BDNF levels are dysregulated.
Ding, Jian-Dong; Tang, Xian-Ye; Shi, Jian-Gang; Jia, Lian-Shun
BDNF has a widespread distribution in the central and peripheral nervous systems, suggesting that BDNF may play a role in the regulation of motor control. However, the direct actions of BDNF on the motoneurons and their underlying mechanisms are still largely unknown to date. Therefore, by using whole-cell patch clamp recordings, quantitative RT-PCR and immunocytochemistry, the present study was designed to investigate the effects of BDNF on electrical activity and glycinergic transmission on the motoneurons and the underlying receptor mechanism. The results reveal: (i) BDNF did not produce a direct excitatory or inhibitory effect on the motoneurons; (ii) BDNF dose-dependently increased the glycinergic transmission on the motoneurons; (iii) glycinergic transmission on motoneurons was a direct postsynaptic effect; (iv) BDNF-induced enhancement of the glycinergic transmission was mediated by the activation of TrkB receptors; and (v) BDNF and its receptors TrkB had an extensive expression in the motoneurons. These results suggest that BDNF is directly involved in the regulation of glycinergic transmission on the motoneurons through postsynaptic TrkB receptors. Considering that the glycinergic synaptic transmission of motoneurons mainly comes from Renshaw cells, the important inhibitory interneurons of spinal cord, we speculate that BDNF may play an important role in the information integration in the spinal cord and participate in the sensitivity of motoneurons.
Stephanie C Licata
Full Text Available Benzodiazepines (BZs are safe drugs for treating anxiety, sleep, and seizure disorders, but their use also results in unwanted effects including memory impairment, abuse, and dependence. The present study aimed to reveal the molecular mechanisms that may contribute to the effects of BZs in the hippocampus (HIP, an area involved in drug-related plasticity, by investigating the regulation of immediate early genes following BZ administration. Previous studies have demonstrated that both brain derived neurotrophic factor (BDNF and c-Fos contribute to memory- and abuse-related processes that occur within the HIP, and their expression is altered in response to BZ exposure. In the current study, mice received acute or repeated administration of BZs and HIP tissue was analyzed for alterations in BDNF and c-Fos expression. Although no significant changes in BDNF or c-Fos were observed in response to twice-daily intraperitoneal (i.p. injections of diazepam (10 mg/kg + 5 mg/kg or zolpidem (ZP; 2.5 mg/kg + 2.5 mg/kg, acute i.p. administration of both triazolam (0.03 mg/kg and ZP (1.0 mg/kg decreased BDNF protein levels within the HIP relative to vehicle, without any effect on c-Fos. ZP specifically reduced exon IV-containing BDNF transcripts with a concomitant increase in the association of methyl-CpG binding protein 2 (MeCP2 with BDNF promoter IV, suggesting that MeCP2 activity at this promoter may represent a ZP-specific mechanism for reducing BDNF expression. ZP also increased the association of phosphorylated cAMP response element binding protein (pCREB with BDNF promoter I. Future work should examine the interaction between ZP and DNA as the cause for altered gene expression in the HIP, given that BZs can enter the nucleus and intercalate into DNA directly.
Su, Bo; Ji, Yun-Song; Sun, Xu-lu; Liu, Xiang-Hua; Chen, Zhe-Yu
Appropriate mitochondrial transport and distribution are essential for neurons because of the high energy and Ca(2+) buffering requirements at synapses. Brain-derived neurotrophic factor (BDNF) plays an essential role in regulating synaptic transmission and plasticity. However, whether and how BDNF can regulate mitochondrial transport and distribution are still unclear. Here, we find that in cultured hippocampal neurons, application of BDNF for 15 min decreased the percentage of moving mitochondria in axons, a process dependent on the activation of the TrkB receptor and its downstream PI3K and phospholipase-Cγ signaling pathways. Moreover, the BDNF-induced mitochondrial stopping requires the activation of transient receptor potential canonical 3 and 6 (TRPC3 and TRPC6) channels and elevated intracellular Ca(2+) levels. The Ca(2+) sensor Miro1 plays an important role in this process. Finally, the BDNF-induced mitochondrial stopping leads to the accumulation of more mitochondria at presynaptic sites. Mutant Miro1 lacking the ability to bind Ca(2+) prevents BDNF-induced mitochondrial presynaptic accumulation and synaptic transmission, suggesting that Miro1-mediated mitochondrial motility is involved in BDNF-induced mitochondrial presynaptic docking and neurotransmission. Together, these data suggest that mitochondrial transport and distribution play essential roles in BDNF-mediated synaptic transmission.
Laing, Katharine R; Mitchell, David; Wersching, Heike; Czira, Maria E; Berger, Klaus; Baune, Bernhard T
Cognitive aging processes are underpinned by multiple processes including genetic factors. The brain-derived neurotrophic factor (BDNF) has been suggested to be involved in age-related cognitive decline in otherwise healthy individuals. The gender-specific role of the BDNF gene in cognitive aging remains unclear. The identification of genetic biomarkers might be a useful approach to identify individuals at risk of cognitive decline during healthy aging processes. The aim of this study was to investigate the associations between three single-nucleotide polymorphisms (SNPs) in the BDNF gene and domains of cognitive functioning in normal cognitive aging. The sample, comprising 369 participants (M = 72.7 years, SD = 4.45 years), completed an extensive neuropsychological test battery measuring memory, motor function, and perceptual speed. The relationships between the SNPs rs6265, rs7103411, and rs7124442 and cognitive domains were examined. While significant main effects of BDNF SNPs on cognitive function were found for the association between rs7103411 and memory performance, gender-specific analyses revealed for females significant main effects of rs7103411 for memory and of rs6265 for perceptual speed independent of the APOE*E4 status and education. The finding for the association between rs6265 and perceptual speed in females remained significant after Bonferroni correction for multiple comparisons. None of the analyses showed significant results for males. This study is the first to implicate that the SNPs rs6265 and rs7103411 affect cognitive function in the elderly in a gender-specific way.
Park, Min-Hyeon; Chang, Kiki D; Hallmayer, Joachim; Howe, Meghan E; Kim, Eunjoo; Hong, Seung Chul; Singh, Manpreet K
Several genetic and environmental factors place youth offspring of parents with bipolar disorder (BD) at high risk for developing mood and anxiety disorders. Recent studies suggest that anxiety symptoms, even at subclinical levels, have been associated with an increased risk for developing BD. The brain-derived neurotrophic factor (BDNF) gene has been implicated in the pathophysiology of both BD and anxiety disorders. We aimed to explore whether anxiety in BD offspring was associated with the BDNF Val66Met polymorphism. 64 BD offspring (mean age: 13.73 (S.D. 3.45) M = 30, F = 34) and 51 HC (mean age: 13.68 (S.D. 2.68) M = 23, F = 28) were compared on presence of the met allele and on scores from the Multidimensional Anxiety Scale for Children (MASC). To assess family function, we used the Family Adaptability and Cohesion Evaluation Scales (FACES-IV). The Baron & Kenny method was the statistical approach used to examine the moderating effects between variables. BD offspring showed higher levels of overall anxiety than did the HC group. BD offspring with the val/val genotype showed higher levels of anxiety than BD offspring with other genotypes. No significant levels of anxiety or its association with BDNF genotype were found in the HC group. BD offspring group showed significantly more family dysfunction when compared with the HC group and the family dysfunction moderated the association between the BDNF genotype and anxiety symptoms. This study demonstrated the potential interplay of three factors: BD offspring, anxiety symptoms and family dysfunction.
Lanz, Thomas A; Bove, Susan E; Pilsmaker, Catherine D; Mariga, Abigail; Drummond, Elena M; Cadelina, Gregory W; Adamowicz, Wendy O; Swetter, Brentt J; Carmel, Sharon; Dumin, Jo Ann; Kleiman, Robin J
Adult rats were treated acutely with peripheral kainic acid (KA), and changes in brain-derived neurotrophic factor (BDNF) mRNA and protein were tracked over time across multiple brain regions. Despite robust elevation in both mRNA and protein in multiple brain regions, plasma BDNF was unchanged and cerebrospinal fluid (CSF) BDNF levels remained undetectable. Primary neurons were then treated with KA. BDNF was similarly elevated within neurons, but was undetectable in neuronal media. Thus, while deficits in BDNF signaling have been implicated in a number of diseases, these data suggest that extracellular concentrations of BDNF may not be a facile biomarker for changes in neurons.
Levada, O A; Cherednichenko, N V
In this review current publications about neurobiology and marker value of brain derived neurotrophic factor (BDNF) in neuropsychiatry are analyzed. It is shown that BDNF is an important member of the family of neurotrophins which widely represented in various structures of the CNS. In prenatal period BDNF is involved in all stages of neuronal networks formation, and in the postnatal period its main role is maintaining the normal brain architectonics, involvement in the processes of neurogenesis and realization of neuroprotective functions. BDNF plays an important role in learning and memory organization, food and motor behavior. BDNF brain expression decreases with age, as well as in degenerative and vascular dementias, affective, anxiety, and behavioral disorders. The reducing of BDNF serum, level reflects the decreasing of its cerebral expression and could be used as a neurobiological marker of these pathological processes but the rising of its concentration could indicate the therapy effectiveness.
Grundy, P L; Patel, N; Harbuz, M S; Lightman, S L; Sharples, P M
Brain-derived neurotrophic factor (BDNF) expression in rat hippocampus is increased after experimental traumatic brain injury (TBI) and may be neuroprotective. Glucocorticoids are important regulators of brain neurotrophin levels and are often prescribed following TBI. The effect of adrenalectomy (ADX) on the expression of BDNF mRNA in the hippocampus after TBI has not been investigated to date. We used fluid percussion injury (FPI) and in situ hybridization to evaluate the expression of BDNF mRNA in the hippocampus 4 h after TBI in adrenal-intact or adrenalectomized rats (with or without corticosterone replacement). FPI and ADX independently increased expression of BDNF mRNA. In animals undergoing FPI, prior ADX caused further elevation of BDNF mRNA and this upregulation was prevented by corticosterone replacement in ADX rats. These findings suggest that glucocorticoids are involved in the modulation of the BDNF mRNA response to TBI.
Valiente-Gómez, Alicia; Amann, Benedikt L; Mármol, Frederic; Oliveira, Cristina; Messeguer, Ana; Lafuente, Amalia; Pomarol-Clotet, Edith; Bernardo Arroyo, Miguel
The aim of this study was to compare serum BDNF levels of chronic schizophrenic patients, with or without deficit syndrome, and healthy controls. A comparative study of serum BDNF levels, determined by ELISA, was performed in 47 chronic patients with schizophrenia matched with 47 healthy controls. A part of the chronic schizophrenic sample was further divided into patients with a deficit (n=14) and a nondeficit syndrome (n=20), according to the Proxy for the Deficit Syndrome Scale. A significant difference was observed in decreased serum BDNF levels between chronic schizophrenia and healthy controls. No statistical significant differences in BDNF levels between deficit and nondeficit chronic schizophrenic patients were found. Our study confirms differences of serum BDNF levels of chronic schizophrenia and healthy controls, which correspond to the clinical progression of the disease. Our results do not support a relation between deficit profile in chronic schizophrenia and lower serum BDNF levels.
Lauterborn, J C; Poulsen, F R; Stinis, C T;
Activity-induced brain-derived neurotrophic factor (BDNF) expression is negatively modulated by circulating adrenal steroids. The rat BDNF gene gives rise to four major transcript forms that each contain a unique 5' exon (I-IV) and a common 3' exon (V) that codes for BDNF protein. Exon......-specific in situ hybridization was used to determine if adrenalectomy has differential effects on basal and activity-induced BDNF transcript expression in hippocampus. Adrenalectomy alone had only modest effects on BDNF mRNA levels with slight increases in exon III-containing mRNA with 7-10-day survival...... no effect on exon IV-containing mRNA content. These results demonstrate that the negative effects of adrenal hormones on activity-induced BDNF expression are by far the greatest for transcripts containing exons I and II. Together with evidence for region-specific transcript expression, these results suggest...
Full Text Available One of the cardinal features of neural development and adult plasticity is the contribution of activity-dependent signaling pathways. However, the interrelationships between different activity-dependent genes are not well understood. The immediate early gene neuronal-activity-regulated pentraxin (NPTX2 or Narp encodes a protein that has been associated with excitatory synaptogenesis, AMPA receptor aggregation, and the onset of critical periods. Here, we show that Narp is a direct transcriptional target of brain-derived neurotrophic factor (BDNF, another highly regulated activity-dependent gene involved in synaptic plasticity. Unexpectedly, Narp is bidirectionally regulated by BDNF. Acute BDNF withdrawal results in downregulation of Narp, whereas transcription of Narp is greatly enhanced by BDNF. Furthermore, our results show that BDNF directly regulates Narp to mediate glutamatergic transmission and mossy fiber plasticity. Hence, Narp serves as a significant epistatic target of BDNF to regulate synaptic plasticity during periods of dynamic activity.
Patwardhan Amol M
Full Text Available Abstract Background Nerve growth factor (NGF, glial cell line-derived neurotrophic factor (GDNF and brain-derived neurotrophic factor (BDNF all play important roles in the development of the peripheral sensory nervous system. Additionally, these growth factors are proposed to modulate the properties of the sensory system in the adult under pathological conditions brought about by nerve injury or inflammation. We have examined the effects of NGF, GDNF and BDNF on adult rat trigeminal ganglion (TG neurons in culture to gain a better understanding of how these growth factors alter the cytochemical and functional phenotype of these neurons, with special attention to properties associated with nociception. Results Compared with no growth factor controls, GDNF, at 1 and 100 ng/ml, significantly increased by nearly 100% the number of neurons in culture at 5 days post-plating. A significant, positive, linear trend of increasing neuron number as a function of BDNF concentration was observed, also peaking at nearly 100%. NGF treatment was without effect. Chronic treatment with NGF and GDNF significantly and concentration-dependently increased 100 nM capsaicin (CAP-evoked calcitonin gene-related peptide (CGRP release, reaching approximately 300% at the highest concentration tested (100 ng/ml. Also, NGF and GDNF each augmented anandamide (AEA- and arachidonyl-2-chloroethylamide (ACEA-evoked CGRP release, while BDNF was without effect. Utilizing immunohistochemistry to account for the proportions of TRPV1- or CGRP-positive neurons under each growth factor treatment condition and then standardizing evoked CGRP release to these proportions, we observed that NGF was much more effective in enhancing CAP- and 50 mM K+-evoked CGRP release than was GDNF. Furthermore, NGF and GDNF each altered the concentration-response function for CAP- and AEA-evoked CGRP release, increasing the Emax without altering the EC50 for either compound. Conclusions Taken together, our
Hartmann, Matthias; Heumann, Rolf; Lessmann, Volkmar
The protein brain-derived neurotrophic factor (BDNF) has been postulated to be a retrograde or paracrine synaptic messenger in long-term potentiation and other forms of activity-dependent synaptic plasticity. Although crucial for this concept, direct evidence for the activity-dependent synaptic release of BDNF is lacking. Here we investigate secretion of BDNF labelled with green fluorescent protein (BDNF–GFP) by monitoring the changes in fluorescence intensity of dendritic BDNF–GFP vesicles a...
Trajkovska, Viktorija; Vinberg, Maj; Aznar, Susana
and protected against affective disorder. Whole blood assessed for BDNF concentrations and correlated to risk status, neuroticism, and number of stressful life events. RESULTS: Between the groups, we found no significant difference in whole blood BDNF levels. Women at high-risk for depression who had...... neuroticism scores and two or less recent stressful events were associated with decreased whole blood BDNF levels (n=50, p
Full Text Available BACKGROUND: The blood brain barrier (BBB and truncated trkB receptor on astrocytes prevent the penetration of brain derived neurotrophic factor (BDNF applied into the peripheral (PNS and central nervous system (CNS thus restrict its application in the treatment of nervous diseases. As BDNF is anterogradely transported by axons, we propose that peripherally derived and/or applied BDNF may act on the regeneration of central axons of ascending sensory neurons. METHODOLOGY/PRINCIPAL FINDINGS: The present study aimed to test the hypothesis by using conditioning lesion of the sciatic nerve as a model to increase the expression of endogenous BDNF in sensory neurons and by injecting exogenous BDNF into the peripheral nerve or tissues. Here we showed that most of regenerating sensory neurons expressed BDNF and p-CREB but not p75NTR. Conditioning-lesion induced regeneration of ascending sensory neuron and the increase in the number of p-Erk positive and GAP-43 positive neurons was blocked by the injection of the BDNF antiserum in the periphery. Enhanced neurite outgrowth of dorsal root ganglia (DRG neurons in vitro by conditioning lesion was also inhibited by the neutralization with the BDNF antiserum. The delivery of exogenous BDNF into the sciatic nerve or the footpad significantly increased the number of regenerating DRG neurons and regenerating sensory axons in the injured spinal cord. In a contusion injury model, an injection of BDNF into the footpad promoted recovery of motor functions. CONCLUSIONS/SIGNIFICANCE: Our data suggest that endogenous BDNF in DRG and spinal cord is required for the enhanced regeneration of ascending sensory neurons after conditioning lesion of sciatic nerve and peripherally applied BDNF may have therapeutic effects on the spinal cord injury.
Yi, Hyun; Hu, Jianfei; Qian, Jiang; Hackam, Abigail S.
BDNF is a well-characterized neurotrophin that mediates a wide variety of activities in the central nervous system (CNS), including neuronal differentiation, neuroprotection and synaptic plasticity. The canonical Wnt signaling pathway is a critical regulator of embryonic development and homeostasis in adult tissues. Our group and others recently demonstrated that Wnt signaling induces BDNF expression in neurons and glia. However, the precise relationship between BDNF and Wnt signaling pathway...
The depolarising action of the neurotransmitter GABA enables a route for local Ca2+ entry into immature neurons and therefore plays an important role in neuronal maturation. We have characterised neuronal GABAA receptor activity in slices comprising the superficial gray layer of the late embryonic and early postnatal mouse superior colliculus and compared wild type (bdnf+/+) and BDNF-deficient (bdnf-/-) preparations. Whole-cell or gramicidin-perforated patch recordings and Ca2+ imaging exper...
Walsh, Jessica J; Friedman, Allyson K; Sun, Haosheng; Heller, Elizabeth A; Ku, Stacy M; Juarez, Barbara; Burnham, Veronica L; Mazei-Robison, Michelle S; Ferguson, Deveroux; Golden, Sam A; Koo, Ja Wook; Chaudhury, Dipesh; Christoffel, Daniel J; Pomeranz, Lisa; Friedman, Jeffrey M; Russo, Scott J; Nestler, Eric J; Han, Ming-Hu
Mechanisms controlling release of brain-derived neurotrophic factor (BDNF) in the mesolimbic dopamine reward pathway remain unknown. We report that phasic optogenetic activation of this pathway increases BDNF amounts in the nucleus accumbens (NAc) of socially stressed mice but not of stress-naive mice. This stress gating of BDNF signaling is mediated by corticotrophin-releasing factor (CRF) acting in the NAc. These results unravel a stress context-detecting function of the brain's mesolimbic circuit.
Maqsood, Raeesah; Stone, Trevor W
Gastro-intestinal (GI) microbiota and the 'gut-brain axis' are proving to be increasingly relevant to early brain development and the emergence of psychiatric disorders. This review focuses on the influence of the GI tract on Brain-Derived Neurotrophic Factor (BDNF) and its relationship with receptors for N-methyl-D-aspartate (NMDAR), as these are believed to be involved in synaptic plasticity and cognitive function. NMDAR may be associated with the development of schizophrenia and a range of other psychopathologies including neurodegenerative disorders, depression and dementias. An analysis of the routes and mechanisms by which the GI microbiota contribute to the pathophysiology of BDNF-induced NMDAR dysfunction could yield new insights relevant to developing novel therapeutics for schizophrenia and related disorders. In the absence of GI microbes, central BDNF levels are reduced and this inhibits the maintenance of NMDAR production. A reduction of NMDAR input onto GABA inhibitory interneurons causes disinhibition of glutamatergic output which disrupts the central signal-to-noise ratio and leads to aberrant synaptic behaviour and cognitive deficits. Gut microbiota can modulate BDNF function in the CNS, via changes in neurotransmitter function by affecting modulatory mechanisms such as the kynurenine pathway, or by changes in the availability and actions of short chain fatty acids (SCFAs) in the brain. Interrupting these cycles by inducing changes in the gut microbiota using probiotics, prebiotics or antimicrobial drugs has been found promising as a preventative or therapeutic measure to counteract behavioural deficits and these may be useful to supplement the actions of drugs in the treatment of CNS disorders.
Maqsood, Raeesah; Stone, Trevor W.
Gastro-intestinal (GI) microbiota and the ‘gut-brain axis’ are proving to be increasingly relevant to early brain development and the emergence of psychiatric disorders. This review focuses on the influence of the GI tract on Brain-Derived Neurotrophic Factor (BDNF) and its relationship with receptors for N-methyl-d-aspartate (NMDAR), as these are believed to be involved in synaptic plasticity and cognitive function. NMDAR may be associated with the development of schizophrenia and a range of...
Shulga, A; Rivera, C
Accumulating experimental evidence suggests that groups of neurons in the CNS might react to pathological insults by activating developmental-like programs for survival, regeneration and re-establishment of lost connections. For instance, in cell and animal models it was shown that after trauma mature central neurons become dependent on brain-derived neurotrophic factor (BDNF) trophic support for survival. This event is preceded by a shift of postsynaptic GABAA receptor-mediated responses from hyperpolarization to developmental-like depolarization. These profound functional changes in GABAA receptor-mediated transmission and the requirement of injured neurons for BDNF trophic support are interdependent. Thyroid hormones (THs) play a crucial role in the development of the nervous system, having significant effects on dendritic branching, synaptogenesis and axonal growth to name a few. In the adult nervous system TH thyroxin has been shown to have a neuroprotective effect and to promote regeneration in experimental trauma models. Interestingly, after trauma there is a qualitative change in the regulatory effect of thyroxin on BDNF expression as well as on GABAergic transmission. In this review we provide an overview of the post-traumatic changes in these signaling systems and discuss the potential significance of their interactions for the development of novel therapeutic strategies.
Saucedo Marquez, Cinthia Maria; Vanaudenaerde, Bart; Troosters, Thierry; Wenderoth, Nicole
Exercise can have a positive effect on the brain by activating brain-derived neurotrophic factor (BDNF)-related processes. In healthy humans there appears to be a linear relationship between exercise intensity and the positive short-term effect of acute exercise on BDNF levels (i.e., the highest BDNF levels are reported after high-intensity exercise protocols). Here we performed two experiments to test the effectiveness of two high-intensity exercise protocols, both known to improve cardiovascular health, to determine whether they have a similar efficacy in affecting BDNF levels. Participants performed a continuous exercise (CON) protocol at 70% of maximal work rate and a high-intensity interval-training (HIT) protocol at 90% of maximal work rate for periods of 1 min alternating with 1 min of rest (both protocols lasted 20 min). We observed similar BDNF kinetics in both protocols, with maximal BDNF concentrations being reached toward the end of training (experiment 1). We then showed that both exercise protocols significantly increase BDNF levels compared with a rest condition (CON P = 0.04; HIT P exercise are slightly more effective than continuous high-intensity exercise for elevating serum BDNF. Additionally, 73% of the participants preferred the HIT protocol (P = 0.02). Therefore, we suggest that the HIT protocol might represent an effective and preferred intervention for elevating BDNF levels and potentially promoting brain health.
Kuramoto, Satoshi; Yasuhara, Takao; Agari, Takashi; Kondo, Akihiko; Jing, Meng; Kikuchi, Yoichiro; Shinko, Aiko; Wakamori, Takaaki; Kameda, Masahiro; Wang, Feifei; Kin, Kyohei; Edahiro, Satoru; Miyoshi, Yasuyuki; Date, Isao
Brain-derived neurotrophic factor (BDNF) is a well neurotrophic factor with neuroprotective potentials for various diseases in the central nervous system. However several previous studies demonstrated that BDNF might deteriorate symptoms for epilepsy model of animals by progression of abnormal neurogenesis. We hypothesized that continuous administration of BDNF at low dose might be more effective for epilepsy model of animals because high dose of BDNF was used in many studies. BDNF-secreting cells were genetically made and encapsulated for transplantation. Rats receiving BDNF capsule showed significant amelioration of seizure stage and reduction of the number of abnormal spikes at 7 days after kainic acid administration, compared to those of control group. The number of BrdU and BrdU/doublecortin positive cells in the hippocampus of BDNF group significantly increased, compared to that of control group. NeuN positive cells in the CA1 and CA3 of BDNF group were significantly preserved, compared to control group. In conclusion, low dose administration using encapsulated BDNF-secreting cells exerted neuroprotective effects with enhanced neurogenesis on epilepsy model of rats. These results might suggest the importance of the dose and administrative way of this neurotrophic factor to the epilepsy model of animals.
Petzold, Anne; Psotta, Laura; Brigadski, Tanja; Endres, Thomas; Lessmann, Volkmar
Brain-derived neurotrophic factor (BDNF) is a crucial mediator of neural plasticity and, consequently, of memory formation. In hippocampus-dependent learning tasks BDNF also seems to play an essential role. However, there are conflicting results concerning the spatial learning ability of aging BDNF(+/-) mice in the Morris water maze paradigm. To evaluate the effect of chronic BDNF deficiency in the hippocampus on spatial learning throughout life, we conducted a comprehensive study to test differently aged BDNF(+/-) mice and their wild type littermates in the Morris water maze and to subsequently quantify their hippocampal BDNF protein levels as well as expression levels of TrkB receptors. We observed an age-dependent learning deficit in BDNF(+/-) animals, starting at seven months of age, despite stable hippocampal BDNF protein expression and continual decline of TrkB receptor expression throughout aging. Furthermore, we detected a positive correlation between hippocampal BDNF protein levels and learning performance during the probe trial in animals that showed a good learning performance during the long-term memory test.
Brunetto de Farias, Caroline [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Children' s Cancer Institute, 90420-140 Porto Alegre, RS (Brazil); Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Heinen, Tiago Elias; Pereira dos Santos, Rafael [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Abujamra, Ana Lucia [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Children' s Cancer Institute, 90420-140 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Schwartsmann, Gilberto [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Department of Internal Medicine, School of Medicine, Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); and others
Highlights: Black-Right-Pointing-Pointer BDNF protected HT-29 colorectal cancer cells from the antitumor effect of cetuximab. Black-Right-Pointing-Pointer TrkB inhibition potentiated the antitumor effect of cetuximab. Black-Right-Pointing-Pointer BDNF/TrkB signaling might be involved in resistance to anti-EGFR therapy. -- Abstract: The clinical success of targeted treatment of colorectal cancer (CRC) is often limited by resistance to anti-epidermal growth factor receptor (EGFR) therapy. The neurotrophin brain-derived neurotrophic factor (BDNF) and its receptor TrkB have recently emerged as anticancer targets, and we have previously shown increased BDNF levels in CRC tumor samples. Here we report the findings from in vitro experiments suggesting that BDNF/TrkB signaling can protect CRC cells from the antitumor effects of EGFR blockade. The anti-EGFR monoclonal antibody cetuximab reduced both cell proliferation and the mRNA expression of BDNF and TrkB in human HT-29 CRC cells. The inhibitory effect of cetuximab on cell proliferation and survival was counteracted by the addition of human recombinant BDNF. Finally, the Trk inhibitor K252a synergistically enhanced the effect of cetuximab on cell proliferation, and this effect was blocked by BDNF. These results provide the first evidence that increased BDNF/TrkB signaling might play a role in resistance to EGFR blockade. Moreover, it is possible that targeting TrkB could potentiate the anticancer effects of anti-EGFR therapy.
Hu, Peter; Kalb, Robert G.; Walton, K. D. (Principal Investigator)
The survival promoting and neuroprotective actions of brain-derived neurotrophic factor (BDNF) are well known but under certain circumstances this growth factor can also exacerbate excitotoxic insults to neurons. Prior exploration of the receptor through which BDNF exerts this action on motor neurons deflects attention away from p75. Here we investigated the possibility that BDNF acts through the receptor tyrosine kinase, TrkB, to confer on motor neurons sensitivity to excitotoxic challenge. We blocked BDNF activation of TrkB using a dominant negative TrkB mutant or a TrkB function blocking antibody, and found that this protected motor neurons against excitotoxic insult in cultures of mixed spinal cord neurons. Addition of a function blocking antibody to BDNF to mixed spinal cord neuron cultures is also neuroprotective indicating that endogenously produced BDNF participates in vulnerability to excitotoxicity. We next examined the intracellular signaling cascades that are engaged upon TrkB activation. Previously we found that inhibition of the phosphatidylinositide-3'-kinase (PI3'K) pathway blocks BDNF-induced excitotoxic sensitivity. Here we show that expression of a constitutively active catalytic subunit of PI3'K, p110, confers excitotoxic sensitivity (ES) upon motor neurons not incubated with BDNF. Parallel studies with purified motor neurons confirm that these events are likely to be occuring specifically within motor neurons. The abrogation of BDNF's capacity to accentuate excitotoxic insults may make it a more attractive neuroprotective agent.
Rudge, J S; Mather, P E; Pasnikowski, E M; Cai, N; Corcoran, T; Acheson, A; Anderson, K; Lindsay, R M; Wiegand, S J
Systemic administration of the excitotoxin kainic acid to adult rats results in a well defined pattern of loss of the CA1 and CA3 pyramidal neurons of the hippocampus. Prior to this neuronal loss, brain-derived neurotrophic factor (BDNF) mRNA is substantially increased. We show here that BDNF protein is increased after excitotoxic insult in specific areas of the hippocampus, reaching maximal levels 24 h after the insult. BDNF protein levels in the hippocampus increase in direct relation to the severity of seizure. Up to 7 days after injection of kainic acid, levels of full-length TrkB protein were unchanged, whereas levels of truncated TrkB protein were significantly increased by 12 h. To determine whether elevations in BDNF protein levels are potentially beneficial to hippocampal neurons exposed to an excitotoxic stress, we infused exogenous BDNF prior to and during the period of neuronal death caused by kainic acid. We find that administration of high levels of exogenous BDNF does not affect severity of seizure, but does in fact, exacerbate the injury caused by kainic acid, specifically to CA3 pyramidal neurons. Although there was a trend toward sparing of CA1 pyramidal neurons on the side infused with BDNF, this was not significant. In the same paradigm, infusion of exogenous NT-3 had no effect.
Mao, Xiao-Yuan; Cao, Yong-Gang; Ji, Zhong; Zhou, Hong-Hao; Liu, Zhao-Qian; Sun, Hong-Li
Topiramate (TPM) was previously found to have neuroprotection against neuronal injury in epileptic and ischemic models. However, whether TPM protects against glutamate-induced excitotoxicity in hippocampal neurons is elusive. Our present work aimed to evaluate the protective effect of TPM against glutamate toxicity in hippocampal neurons and further figure out the potential molecular mechanisms. The in vitro glutamate excitotoxic model was prepared with 125μM glutamate for 20min. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) analysis and Hoechst 33342 staining were conducted to detect neuronal survival. The protein expressions of brain-derived neurotrophic factor (BDNF), TrkB, mitogen-activated protein kinase (MAPK) cascade (including extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 MAPK), cyclic AMP response element binding protein (CREB), Bcl-2, Bax and β-actin were detected via Western blot assay. Our results demonstrated that TPM protected hippocampal neurons from glutamate toxicity. Meanwhile, the pretreatment of TPM for 10min significantly prevented the down-regulation of BDNF and the phosphorylation of TrkB. Furthermore, the elevation of phosphorylated EKR expression was significantly inhibited after blockade of TrkB by TrkB IgG, while no alterations of phosphorylated JNK and p38 MAPK were found in the cultured hippocampal neurons. Besides, it was also found that the enhanced phosphorylation of CREB was evidently reversed under excitotoxic conditions after treating with U0126 (the selective inhibitor of ERK). The protein level of Bcl-2 was also observed to be remarkably increased after TPM treatment. In conclusion, these findings implicate that TPM exerts neuroprotective effects against glutamate excitotoxicity in hippocampal neurons and its protection may be modulated through BDNF/TrkB-dependent ERK pathway.
Nowacka, Marta; Obuchowicz, Ewa
Stress is known to play an important role in etiology, development and progression of affective diseases. Especially, chronic stress, by initiating changes in the hypothalamic-pituitary-adrenal axis (HPA), neurotransmission and the immune system, acts as a trigger for affective diseases. It has been reported that the rise in the concentration of pro-inflammatory cytokines and persistent up-regulation of glucocorticoid expression in the brain and periphery increases the excitotoxic effect on CA3 pyramidal neurons in the hippocampus resulting in dendritic atrophy, apoptosis of neurons and possibly inhibition of neurogenesis in adult brain. Stress was observed to disrupt neuroplasticity in the brain, and growing evidence demonstrates its role in the pathomechanism of affective disorders. Experimental studies indicate that a well-known brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) which have recently focused increasing attention of neuroscientists, promote cell survival, positively modulate neuroplasticity and hippocampal neurogenesis. In this paper, we review the alterations in BDNF and VEGF pathways induced by chronic and acute stress, and their relationships with HPA axis activity. Moreover, behavioral effects evoked in rodents by both above-mentioned factors and the effects consequent to their deficit are presented. Biochemical as well as behavioral findings suggest that BDNF and VEGF play an important role as components of cascade of changes in the pathomechanism of stress-induced affective diseases. Further studies on the mechanisms regulating their expression in stress conditions are needed to better understand the significance of trophic hypothesis of stress-induced affective diseases.
Kretschmer, Tina; Vitaro, Frank; Barker, Edward D.
Peer antisocial behavior robustly predicts adolescents' own behavior, but not all adolescents are equally vulnerable to their peers' influence and genetic factors may confer vulnerability. This study used data of n=3,081 adolescents from the Avon Longitudinal Study of Parents and Children to examine
Aureli, A; Del Beato, T; Sebastiani, P; Marimpietri, A; Melillo, C V; Sechi, E; Di Loreto, S
Symptoms of attention-deficit hyperactivity disorder (ADHD) have been found in several studies of children with intellectual disabilities (ID) but the two diseases are not always associated. Several lines of evidence implicate the involvement of brain-derived neurotrophic factor (BDNF) in ADHD, and it may also be relevant in ID due to its known involvement in the development of the central nervous system (CNS) and in learning/memory functions. We genotyped paediatric patients with ADHD and ID for the Val66Met and 270 C/T polymorphisms in BDNF. Diagnosis of ADHD and ID was confirmed by the clinicians in accordance with DSM-IV criteria. The G/A genotype of the Val66Met SNP was associated with both ADHD and ID, and the G allele was significantly associated with ADHD. The C/C genotype of the C270T SNP was significantly overrepresented in both ADHD and ID groups compared with the controls. Data suggest that both BDNF polymorphisms could play a role in the etiology of ADHD. In addition, we present the first results suggesting that these BDNF SNPs are significantly associated with ID.
Aarse, Janna; Herlitze, Stefan
ABSTRACT Brain‐derived neurotrophic factor (BDNF) supports neuronal survival, growth, and differentiation and has been implicated in forms of hippocampus‐dependent learning. In vitro, a specific role in hippocampal synaptic plasticity has been described, although not all experience‐dependent forms of synaptic plasticity critically depend on BDNF. Synaptic plasticity is likely to enable long‐term synaptic information storage and memory, and the induction of persistent (>24 h) forms, such as long‐term potentiation (LTP) and long‐term depression (LTD) is tightly associated with learning specific aspects of a spatial representation. Whether BDNF is required for persistent (>24 h) forms of LTP and LTD, and how it contributes to synaptic plasticity in the freely behaving rodent has never been explored. We examined LTP, LTD, and related forms of learning in the CA1 region of freely dependent mice that have a partial knockdown of BDNF (BDNF+/−). We show that whereas early‐LTD (BDNF, short‐term depression (BDNF is required for LTP that is induced by mild, but not strong short afferent stimulation protocols. Object‐place learning triggers LTD in the CA1 region of mice. We observed that object‐place memory was impaired and the object‐place exploration failed to induce LTD in BDNF+/− mice. Furthermore, spatial reference memory, that is believed to be enabled by LTP, was also impaired. Taken together, these data indicate that BDNF is required for specific, but not all, forms of hippocampal‐dependent information storage and memory. Thus, very robust forms of synaptic plasticity may circumvent the need for BDNF, rather it may play a specific role in the optimization of weaker forms of plasticity. The finding that both learning‐facilitated LTD and spatial reference memory are both impaired in BDNF+/− mice, suggests moreover, that it is critically required for the physiological encoding of hippocampus‐dependent memory. © 2015 The Authors
Moy, Gregory A; McNay, Ewan C
Obesity, high-fat diets, and subsequent type 2 diabetes (T2DM) are associated with cognitive impairment. Moreover, T2DM increases the risk of Alzheimer's disease (AD) and leads to abnormal elevation of brain beta-amyloid levels, one of the hallmarks of AD. The psychoactive alkaloid caffeine has been shown to have therapeutic potential in AD but the central impact of caffeine has not been well-studied in the context of a high-fat diet. Here we investigated the impact of caffeine administration on metabolism and cognitive performance, both in control rats and in rats placed on a high-fat diet. The effects of caffeine were significant: caffeine both (i) prevented the weight-gain associated with the high-fat diet and (ii) prevented cognitive impairment. Caffeine did not alter hippocampal metabolism or insulin signaling, likely because the high-fat-fed animals did not develop full-blown diabetes; however, caffeine did prevent or reverse a decrease in hippocampal brain-derived neurotrophic factor (BDNF) seen in high-fat-fed animals. These data confirm that caffeine may serve as a neuroprotective agent against cognitive impairment caused by obesity and/or a high-fat diet. Increased hippocampal BDNF following caffeine administration could explain, at least in part, the effects of caffeine on cognition and metabolism.
Full Text Available Ethanol consumption during pregnancy may induce profound changes in fetal CNS development. We postulate that some of the effects of ethanol on striatal glutamatergic transmission and neurotrophin expression could be modulated by allopregnanolone, a neurosteroid modulator of GABAA receptor activity. We describe the acute pharmacological effect of allopregnanolone (65 μg/kg, s.c. administered to juvenile male rats (day 21 of age on the corticostriatal glutamatergic pathway, in both control and prenatally ethanol-exposed rats (two ip injections of 2.9 g/kg in 24% v/v saline solution on gestational day 8. Prenatal ethanol administration decreased the K+-induced release of glutamate regarding the control group. Interestingly, this effect was reverted by allopregnanolone. Regarding BDNF, allopregnanolone decreases the content of this neurotrophic factor in the striatum of control groups. However, both ethanol alone and ethanol plus allopregnanolone treated animals did not show any change regarding control values. We suggest that prenatal ethanol exposure may produce an alteration of GABAA receptors which blocks the GABA agonist-like effect of allopregnanolone on rapid glutamate release, thus disturbing normal neural transmission. Furthermore, the reciprocal interactions found between GABAergic neurosteroids and BDNF could underlie mechanisms operating during the neuronal plasticity of fetal development.
Martin, Jean-Luc; Finsterwald, Charles
Ample evidence supports a role of brain-derived neurotrophic factor (BDNF) in the survival and differentiation of selective populations of neurons in the peripheral and central nervous systems. In addition to its trophic actions, BDNF exerts acute effects on synaptic transmission and plasticity. In particular, BDNF enhances excitatory synaptic transmission through pre- and postsynaptic mechanisms. In this regard, BDNF enhances glutamate release, the frequency of miniature excitatory postsynaptic currents (mEPSCs), NMDA receptor activity and the phosphorylation of NMDA receptor subunits. Our recent studies revealed a novel cooperative interaction between BDNF and glutamate in the regulation of dendritic development. Indeed, we found that the effects of BDNF on dendritic growth of cortical neurons require both the stimulation of cAMP response element-binding protein (CREB) phosphorylation by BDNF and the activation of the CREB-regulated transcription coactivator 1 (CRTC1) by glutamate. Together, these studies highlight the importance of the cooperation between BDNF and glutamate in the regulation of synaptic transmission and neuronal development.
Regina Lynn Leckie
Full Text Available Executive function declines with age, but engaging in aerobic exercise may attenuate decline. One mechanism by which aerobic exercise may preserve executive function is through the up-regulation of brain-derived neurotropic factor (BDNF, which also declines with age. The present study examined BDNF as a mediator of the effects of a 1-year walking intervention on executive function in 90 older adults (mean age = 66.82. Participants were randomized to a stretching and toning control group or a moderate intensity walking intervention group. BDNF serum levels and performance on a task-switching paradigm were collected at baseline and follow-up. We found that age moderated the effect of intervention group on changes in BDNF levels, with those in the highest age quartile showing the greatest increase in BDNF after 1-year of moderate intensity walking exercise (p = .036. The mediation analyses revealed that BDNF mediated the effect of the intervention on task-switch accuracy, but did so as a function of age, such that exercise-induced changes in BDNF mediated the effect of exercise on task-switch performance only for individuals over the age of 71. These results demonstrate that both age and BDNF serum levels are important factors to consider when investigating the mechanisms by which exercise interventions influence cognitive outcomes, particularly in elderly populations.
Halievski, Katherine; Henley, Casey L; Domino, Laurel; Poort, Jessica E; Fu, Martina; Katsuno, Masahisa; Adachi, Hiroaki; Sobue, Gen; Breedlove, S Marc; Jordan, Cynthia L
Transgenic expression of neurotrophic factors in skeletal muscle has been found to protect mice from neuromuscular disease, including spinal bulbar muscular atrophy (SBMA), triggering renewed interest in neurotrophic factors as therapeutic agents for treating neuromuscular disease. Because SBMA is an androgen-dependent disease, and brain-derived neurotrophic factor (BDNF) mediates effects of androgens on neuromuscular systems, we asked whether BDNF expression is impaired in two different transgenic (Tg) mouse models of SBMA, the so called "97Q" and "myogenic" SBMA models. The 97Q model globally overexpresses a full length human AR with 97 glutamine repeats whereas the myogenic model of SBMA overexpresses a wild-type rat androgen receptor (AR) only in skeletal muscle fibers. Using quantitative PCR, we find that muscle BDNF mRNA declines in an androgen-dependent manner in both models, paralleling changes in motor function, with robust deficits (6-8 fold) in both fast and slow twitch muscles of impaired Tg males. Castration rescues or reverses disease-related deficits in muscle BDNF mRNA in both models, paralleling its effect on motor function. Moreover, when disease is acutely induced in Tg females, both motor function and muscle BDNF mRNA expression plummet, with the deficit in muscle BDNF emerging before overt motor dysfunction. That androgen-dependent motor dysfunction is tightly associated with a robust and early down-regulation of muscle BDNF mRNA suggests that BDNF delivered to skeletal muscle may have therapeutic value for SBMA.
Langlois, Anais; Diabira, Diabe; Ferrand, Nadine; Porcher, Christophe
The brain-derived neurotrophic factor (BDNF) has emerged as an important messenger for activity-dependent development of neuronal network. Recent findings have suggested that a significant proportion of BDNF can be secreted as a precursor (proBDNF) and cleaved by extracellular proteases to yield the mature form. While the actions of proBDNF on maturation and plasticity of excitatory synapses have been studied, the effect of the precursor on developing GABAergic synapses remains largely unknown. Here, we show that regulated secretion of proBDNF exerts a bidirectional control of GABAergic synaptic activity with NMDA receptors driving the polarity of the plasticity. When NMDA receptors are activated during ongoing synaptic activity, regulated Ca2+-dependent secretion of proBDNF signals via p75NTR to depress GABAergic synaptic activity, while in the absence of NMDA receptors activation, secreted proBDNF induces a p75NTR-dependent potentiation of GABAergic synaptic activity. These results revealed a new function for proBDNF-p75NTR signaling in synaptic plasticity and a novel mechanism by which synaptic activity can modulate the development of GABAergic synaptic connections. PMID:22510533
Dols, A.; Thesing, C.S.; Bouckaert, F.; Oude Voshaar, R.C.; Comijs, H.C.; Stek, M.L.
BACKGROUND: Depression and cognitive decline are highly prevalent in older persons and both are associated with low serum brain derived neurotrophic factor (BDNF). Mutual pathways of depression and cognitive decline in older persons may explain the overlap in symptoms and low serum BDNF. We hypothes
Endres, Thomas; Lessmann, Volkmar
Beyond its trophic function, the neurotrophin BDNF (brain-derived neurotrophic factor) is well known to crucially mediate synaptic plasticity and memory formation. Whereas recent studies suggested that acute BDNF/TrkB signaling regulates amygdala-dependent fear learning, no impairments of cued fear learning were reported in heterozygous BDNF…
Brain derived neurotrophic factor (BDNF) plays essential roles in neuronal survival and differentiation, synaptic plasticity, central regulation of energy homeostasis, and neuronal development of the central and peripheral nerve system. Here, we report two new splicing variants of the chicken BDNF g...
Brandys, Marek K; Kas, Martien J H; van Elburg, Annemarie A; Campbell, Iain C; Adan, Roger A H
OBJECTIVES: Brain derived neurotrophic factor (BDNF) is involved in neuroplasticity, and in the homeostatic regulation of food intake and energy expenditure. It also has a role in stress responsivity and reward processing. On the basis of its involvement in these various processes, BDNF can be hypot
van der Meij, Annemarie; Comijs, Hannie C.; Dols, Annemieke; Janzing, Joost G. E.; Oude Voshaar, Richard
Brain-Derived Neurotrophic Factor (BDNF) serum levels are abnormally low in depressed patients as compared to healthy controls and normalize with SSRI treatment. The aim of this study is to examine serum BDNF levels in late-life depression, stratified for SSRI usage, and to explore the relation betw
The objective of this study is to examine a functional variant (rs6265) in the BDNF gene interacting with dietary intake modulate obesity traits in the Boston Puerto Rican Health Study population. BDNF rs6265 was genotyped in 1147 Puerto Ricans (aged 45-75 years), and examined for association with o...
Brandys, Marek K.; Kas, Martien J. H.; van Elburg, Annemarie A.; Campbell, Iain C.; Adan, Roger A. H.
Objectives. Brain derived neurotrophic factor (BDNF) is involved in neuroplasticity, and in the homeostatic regulation of food intake and energy expenditure. It also has a role in stress responsivity and reward processing. On the basis of its involvement in these various processes, BDNF can be hypot
Dols, Annemiek; Thesing, Carisha S.; Bouckaert, Filip; Oude Voshaar, Richard; Comijs, Hannie C.; Stek, M. L.
Background: Depression and cognitive decline are highly prevalent in older persons and both are associated with low serum brain derived neurotrophic factor (BDNF). Mutual pathways of depression and cognitive decline in older persons may explain the overlap in symptoms and low serum BDNF. We hypothes
Massey, Kerri A; Zago, Wagner M; Berg, Darwin K
In the hippocampus, brain-derived neurotrophic factor (BDNF) regulates a number of synaptic components. Among these are nicotinic acetylcholine receptors containing alpha7 subunits (alpha7-nAChRs), which are interesting because of their relative abundance in the hippocampus and their high relative calcium permeability. We show here that BDNF elevates surface and intracellular pools of alpha7-nAChRs on cultured hippocampal neurons and that glutamatergic activity is both necessary and sufficient for the effect. Blocking transmission through NMDA receptors with APV blocked the BDNF effect; increasing spontaneous excitatory activity with the GABA(A) receptor antagonist bicuculline replicated the BDNF effect. BDNF antibodies blocked the BDNF-mediated increase but not the bicuculline one, consistent with enhanced glutamatergic activity acting downstream from BDNF. Increased alpha7-nAChR clusters were most prominent on interneuron subtypes known to directly innervate excitatory neurons. The results suggest that BDNF, acting through glutamatergic transmission, can modulate hippocampal output in part by controlling alpha7-nAChR levels.
Meij, A. van der; Comijs, H.C.; Dols, A.; Janzing, J.G.E.; Oude Voshaar, R.C.
Brain-Derived Neurotrophic Factor (BDNF) serum levels are abnormally low in depressed patients as compared to healthy controls and normalize with SSRI treatment. The aim of this study is to examine serum BDNF levels in late-life depression, stratified for SSRI usage, and to explore the relation betw
Marosi, Krisztina; Kim, Sang Woo; Moehl, Keelin
. The mechanism by which 3OHB induces Bdnf gene expression involves generation of reactive oxygen species, activation of the transcription factor NF-κB, and activity of the histone acetyltransferase p300/EP300. Because BDNF plays important roles in synaptic plasticity and neuronal stress resistance, our findings...
Itoh, Norimichi; Enomoto, Atsushi; Nagai, Taku; Takahashi, Masahide; Yamada, Kiyofumi
It is well known that synaptic plasticity is the cellular mechanism underlying learning and memory. Activity-dependent synaptic changes in electrical properties and morphology, including synaptogenesis, lead to alterations of synaptic strength, which is associated with long-term potentiation (LTP). Brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) signaling is involved in learning and memory formation by regulating synaptic plasticity. The phosphatidylinositol 3-kinase (PI3-K)/Akt pathway is one of the key signaling cascades downstream BDNF/TrkB and is believed to modulate N-methyl-d-aspartate (NMDA) receptor-mediated synaptic plasticity. However, the molecular mechanism underlying the connection between these two key players in synaptic plasticity remains largely unknown. Girders of actin filament (Girdin), an Akt substrate that directly binds to actin filaments, has been shown to play a role in neuronal migration and neuronal development. Recently, we identified Girdin as a key molecule involved in regulating long-term memory. It was demonstrated that phosphorylation of Girdin by Akt contributed to the maintenance of LTP by linking the BDNF/TrkB signaling pathway with NMDA receptor activity. These findings indicate that Girdin plays a pivotal role in a variety of processes in the CNS. Here, we review recent advances in our understanding about the roles of Girdin in the CNS and focus particularly on neuronal migration and memory.
Hong, Zhen-Yi; Yu, Shuang-Shuang; Wang, Zhi-Jun; Zhu, Yi-Zhun
SCM-198 is an alkaloid found only in Herba leonuri and it has been reported to possess considerable neuroprotective effects in animal models of ischemic stroke, Parkinson's disease and Alzheimer's disease (AD). In this study, we demonstrated for the first time that 3-month oral SCM-198 treatment could significantly improve both recognition and spatial memory, inhibit microgliosis and promote neuronal survival in amyloid-β protein precursor and presenilin-1(AβPP/PS1) double-transgenic mice without affecting amyloid-β (Aβ) burden. In addition, decreases in cAMP-response element-binding protein (CREB) phosphorylation, brain-derived neurotrophic factor (BDNF) and tropomyosin-related kinase B (TrkB) phosphorylation were attenuated by SCM-198 both in vivo and in primary cortical neurons, which could be blocked by protein kinase A (PKA) inhibitors, suggesting the involvement of upstream PKA in enhancing the BDNF/TrkB/CREB signaling by SCM-198. Our results indicate that SCM-198, a drug that could promote neuronal survival and enhance BDNF/TrkB/CREB signaling, has beneficial effects on behavioral and biochemical alterations without affecting Aβ burden in AβPP/PS1 mice and might become a potential drug candidate for AD treatment in the future.
Full Text Available SCM-198 is an alkaloid found only in Herba leonuri and it has been reported to possess considerable neuroprotective effects in animal models of ischemic stroke, Parkinson’s disease and Alzheimer’s disease (AD. In this study, we demonstrated for the first time that 3-month oral SCM-198 treatment could significantly improve both recognition and spatial memory, inhibit microgliosis and promote neuronal survival in amyloid-β protein precursor and presenilin-1(AβPP/PS1 double-transgenic mice without affecting amyloid-β (Aβ burden. In addition, decreases in cAMP-response element-binding protein (CREB phosphorylation, brain-derived neurotrophic factor (BDNF and tropomyosin-related kinase B (TrkB phosphorylation were attenuated by SCM-198 both in vivo and in primary cortical neurons, which could be blocked by protein kinase A (PKA inhibitors, suggesting the involvement of upstream PKA in enhancing the BDNF/TrkB/CREB signaling by SCM-198. Our results indicate that SCM-198, a drug that could promote neuronal survival and enhance BDNF/TrkB/CREB signaling, has beneficial effects on behavioral and biochemical alterations without affecting Aβ burden in AβPP/PS1 mice and might become a potential drug candidate for AD treatment in the future.
Lessmann, Volkmar; Stroh-Kaffei, Sigrid; Steinbrecher, Violetta; Edelmann, Elke; Brigadski, Tanja; Kilb, Werner; Luhmann, Heiko J
BDNF and nitric oxide signaling both contribute to long-term potentiation (LTP) at glutamatergic synapses, but to date, few studies analyzed the interaction of both signaling cascades in the same synaptic pathway. Here we addressed the question whether the residual LTP in the CA1 region of hippocampal slices from heterozygous BDNF knockout mice (BDNF⁺/⁻) is dependent on nitric oxide (NO) signaling. Extracellular recording of synaptic field potentials elicited by presynaptic Schaffer collateral stimulation was performed in the CA1 region of hippocampal slices of 4- to 6-week-old mice, and LTP was induced by a theta burst stimulation protocol. Application of the nitric oxide inhibitor L-NAME (200 μM) strongly inhibited LTP by 70% in wildtype animals. This inhibition of LTP was not a consequence of altered basal synaptic properties. In CA1 of BDNF⁺/⁻ mice, stimulated with the same theta burst protocol, LTP was reduced by 50% as compared to wildtype animals. This impairment in the expression of LTP in BDNF⁺/⁻ mice did not result from an increased synaptic fatigue. The residual LTP in BDNF⁺/⁻ was not further reduced by preincubation of slices with L-NAME. These results suggest that BDNF and NO share overlapping intracellular signaling cascades to mediate LTP in CA1, and part of their signaling cascades are most likely arranged consecutively in the signaling pathway mediating LTP.
Olsen, Ditte; Kaas, Mathias; Schwartz, Ole; Nykjaer, Anders; Glerup, Simon
BDNF-induced signaling is essential for the development of the central nervous system and critical for plasticity in adults. Mature BDNF signals through TrkB, while its precursor proBDNF employs p75[superscript NTR], resulting in activation of signaling cascades with opposite effects on neuronal survival, growth cone decisions, and synaptic…
Full Text Available Background/Aims: Microglia, which represent the immune cells of the central nervous system (CNS, have long been a subject of study in CNS disease research. Substantial evidence indicates that microglial activation functions as a strong neuro-inflammatory response in neuropathic pain, promoting the release of pro-inflammatory cytokines, such as tumor necrosis factor (TNF-α. In addition, activated microglia release brain-derived neurotrophic factor (BDNF, which acts as a powerful cytokine. In this study, we performed a series of in vitro experiments to examine whether a positive autocrine feedback loop existed between microglia-derived BDNF and subsequent microglial activation as well as the mechanisms underlying this positive feedback loop. Methods: Because ATP is a classic inducer of microglial activation, firstly, we examined ATP-activated microglia in the present study. Secondly, we used TrkB/Fc, the BDNF sequester, to eliminate the effects of endogenous BDNF. ATP-stimulated microglia without BDNF was examined. Finally, we used exogenous BDNF to further determine whether BDNF could directly activate BV2 microglia. In all experiments, to quantify BV2 microglia activation, the protein levels of CD11b, a microglial activation marker, were measured by western blot. A Transwell migration assay was used to examine microglial migration. To assess the synthesis and release of proinflammatory cytokines, western blot was used to measure BDNF synthesis, and ELISA was used to quantify TNF-α release. Results: In our present research, we have observed that ATP dramatically activates microglia, enhancing microglial migration, increasing the synthesis of BDNF and up-regulating the release of TNF-α. Microglial activation is inhibited following the sequestration of endogenous BDNF, resulting in impaired microglial migration and decreased TNF-α release. Furthermore, exogenous BDNF can also activate microglia to subsequently enhance migration and increase TNF
Cunha, Carla; Angelucci, Andrea; D'Antoni, Angela; Dobrossy, Mate D; Dunnett, Stephen B; Berardi, Nicoletta; Brambilla, Riccardo
In this study we analyzed the effect on behavior of a chronic exposure to brain-derived neurotrophic factor (BDNF), by analysing a mouse line overexpressing BDNF under the alphaCaMKII promoter, which drives the transgene expression exclusively to principal neurons of the forebrain. BDNF transgenic mice and their WT littermates were examined with a battery of behavioral tests, in order to evaluate motor coordination, learning, short and long-term memory formation. Our results demonstrate that chronic BDNF overexpression in the central nervous system (CNS) causes learning deficits and short-term memory impairments, both in spatial and instrumental learning tasks. This observation suggests that a widespread increase in BDNF in forebrain networks may result in adverse effects on learning and memory formation.
Charrier, Céline; Chigr, Fatiha; Tardivel, Catherine; Mahaut, Stéphanie; Jean, André; Najimi, Mohamed; Moyse, Emmanuel
The dorsal vagal complex (DVC) is the satiety reflex-integrating center of adult mammals. Immobilization stress (IS) is known to elicit anorexia and to up-regulate BDNF expression in adult rat forebrain; intra-DVC delivery of BDNF was shown to elicit anorexia. Therefore, we addressed here whether IS would increase BDNF signaling in rat DVC by using PCR and western-blot on microdissected tissue extracts. Significant variations of BDNF expression in DVC after IS include exon V mRNA increase at 3 h, decreases of both protein and exon III mRNA at 24 h, and exon I mRNA decrease at 72 h. At the receptor level, IS elicited a highly significant induction of both full-length and truncated-1 TrkB mRNAs at 24 h after IS. In vivo recruitment of BDNF signaling in DVC during stress thus differs from hypothalamus, the relevance of which to anorexia is discussed.
Kulkarny, V V; Wiest, N E; Marquez, C P; Nixon, S C; Valenzuela, C F; Perrone-Bizzozero, N I
The adolescent brain is particularly vulnerable to the effects of alcohol, with intoxications at this developmental age often producing long-lasting effects. The present study addresses the effects of a single acute ethanol exposure on growth-associated protein-43 (GAP-43) and brain-derived neurotrophic factor (BDNF) gene expression in neurons in the cerebellum and hippocampus of adolescent rats. Male postnatal day 23 (P23) Sprague-Dawley rats were exposed to ethanol vapors for 2h and after a recovery period of 2h, the cerebellum and hippocampus were harvested and samples were taken for blood alcohol concentration (BAC) determinations. We found that this exposure resulted in a mean BAC of 174 mg/dL, which resembles levels in human adolescents after binge drinking. Analyses of total RNA and protein by quantitative reverse transcription PCR and western blotting, respectively, revealed that this single ethanol exposure significantly decreased the levels of GAP-43 mRNA and protein in the cerebellum but increased the levels of mRNA and protein in the hippocampus. BDNF mRNA and protein levels were also increased in the hippocampus but not in the cerebellum of these animals. In situ hybridizations revealed that GAP-43 and BDNF mRNA levels were primarily increased by alcohol exposure in hippocampal dentate granule cells and CA3 neurons. Overall, the reported alterations in the expression of the plasticity-associated genes GAP-43 and BDNF in juvenile rats are consistent with the known deleterious effects of binge drinking on motor coordination and cognitive function.
Full Text Available The pathogenesis of the schizophrenic illness is still not fully elucidated. Many studies have been conducted revealing different aspects but may be the studies of greatest significance are studying the genetic aspects of expression of trophic factors and enzymes associated with nervous system development and plasticity. In this relation we aimed at measuring the Cyclon and BDNF genes expression in blood of patients suffering from schizophrenia and to test for correlation between them. Our result did not reveal correlation in spite of their connection with the disease
Chen, Lulu Y.; Rex, Christopher S.; Pham, Danielle T.; Lynch, Gary; Gall, Christine M.
Learning-induced neurotrophic signaling at synapses is widely held to be critical for neuronal viability in adult brain. A previous study provided evidence that unsupervised learning of a novel environment is accompanied by activation of the TrkB receptor for Brain-Derived Neurotrophic Factor (BDNF) in hippocampal field CA1b of adult rats. Here we report that this effect is regionally differentiated, in accord with ‘engram’ type memory encoding. A 30-min exposure to a novel, complex environme...
Full Text Available BACKGROUND: Whereas brain-derived neurotrophic factor (BDNF levels are measured in the brain in animal models of stroke, neurotrophin levels in stroke patients are measured in plasma or serum samples. The present study was designed to investigate the meaning of circulating BDNF levels in stroke patients. METHODS AND RESULTS: Unilateral ischemic stroke was induced in rats by the injection of various numbers of microspheres into the carotid circulation in order to mimic the different degrees of stroke severity observed in stroke patients. Blood was serially collected from the jugular vein before and after (4 h, 24 h and 8 d embolization and the whole brains were collected at 4, 24 h and 8 d post-embolization. Rats were then selected from their degree of embolization, so that the distribution of stroke severity in the rats at the different time points was large but similar. Using ELISA tests, BDNF levels were measured in plasma, serum and brain of selected rats. Whereas plasma and serum BDNF levels were not changed by stroke, stroke induced an increase in brain BDNF levels at 4 h and 24 h post-embolization, which was not correlated with stroke severity. Individual plasma BDNF levels did not correlate with brain levels at any time point after stroke but a positive correlation (r = 0.67 was observed between individual plasma BDNF levels and stroke severity at 4 h post-embolization. CONCLUSION: Circulating BDNF levels do not mirror brain BDNF levels after stroke, and severe stroke is associated with high plasma BDNF in the very acute stage.
Falcicchia, Chiara; Trempat, Pascal; Binaschi, Anna; Perrier-Biollay, Coline; Roncon, Paolo; Soukupova, Marie; Berthommé, Hervé; Simonato, Michele
Brain-derived neurotrophic factor (BDNF) has been found to produce pro- but also anti-epileptic effects. Thus, its validity as a therapeutic target must be verified using advanced tools designed to block or to enhance its signal. The aim of this study was to develop tools to silence the BDNF signal. We generated Herpes simplex virus type 1 (HSV-1) derived amplicon vectors, i.e. viral particles containing a genome of 152 kb constituted of concatameric repetitions of an expression cassette, enabling the expression of the gene of interest in multiple copies. HSV-1 based amplicon vectors are non-pathogenic and have been successfully employed in the past for gene delivery into the brain of living animals. Therefore, amplicon vectors should represent a logical choice for expressing a silencing cassette, which, in multiple copies, is expected to lead to an efficient knock-down of the target gene expression. Here, we employed two amplicon-based BDNF silencing strategies. The first, antisense, has been chosen to target and degrade the cytoplasmic mRNA pool of BDNF, whereas the second, based on the convergent transcription technology, has been chosen to repress transcription at the BDNF gene. Both these amplicon vectors proved to be effective in down-regulating BDNF expression in vitro, in BDNF-expressing mesoangioblast cells. However, only the antisense strategy was effective in vivo, after inoculation in the hippocampus in a model of status epilepticus in which BDNF mRNA levels are strongly increased. Interestingly, the knocking down of BDNF levels induced with BDNF-antisense was sufficient to produce significant behavioral effects, in spite of the fact that it was produced only in a part of a single hippocampus. In conclusion, this study demonstrates a reliable effect of amplicon vectors in knocking down gene expression in vitro and in vivo. Therefore, this approach may find broad applications in neurobiological studies.
Full Text Available Brain-derived neurotrophic factor (BDNF has been found to produce pro- but also anti-epileptic effects. Thus, its validity as a therapeutic target must be verified using advanced tools designed to block or to enhance its signal. The aim of this study was to develop tools to silence the BDNF signal. We generated Herpes simplex virus type 1 (HSV-1 derived amplicon vectors, i.e. viral particles containing a genome of 152 kb constituted of concatameric repetitions of an expression cassette, enabling the expression of the gene of interest in multiple copies. HSV-1 based amplicon vectors are non-pathogenic and have been successfully employed in the past for gene delivery into the brain of living animals. Therefore, amplicon vectors should represent a logical choice for expressing a silencing cassette, which, in multiple copies, is expected to lead to an efficient knock-down of the target gene expression. Here, we employed two amplicon-based BDNF silencing strategies. The first, antisense, has been chosen to target and degrade the cytoplasmic mRNA pool of BDNF, whereas the second, based on the convergent transcription technology, has been chosen to repress transcription at the BDNF gene. Both these amplicon vectors proved to be effective in down-regulating BDNF expression in vitro, in BDNF-expressing mesoangioblast cells. However, only the antisense strategy was effective in vivo, after inoculation in the hippocampus in a model of status epilepticus in which BDNF mRNA levels are strongly increased. Interestingly, the knocking down of BDNF levels induced with BDNF-antisense was sufficient to produce significant behavioral effects, in spite of the fact that it was produced only in a part of a single hippocampus. In conclusion, this study demonstrates a reliable effect of amplicon vectors in knocking down gene expression in vitro and in vivo. Therefore, this approach may find broad applications in neurobiological studies.
Nurjono, Milawaty; Tay, Yi Hang; Lee, Jimmy
Brain derived neurotrophic factor (BDNF), which has been implicated in the pathogenesis of schizophrenia, has been recently shown to be involved in the regulation of metabolism and energy homeostasis. This study seeks to examine the relationship between BDNF, metabolic indices and cardiovascular (CVD) risk in patients with schizophrenia. Medical histories, demographic information and anthropometric measurements were collected and analyzed from 61 participants with schizophrenia. Fasting glucose and lipids were measured in a central laboratory, and serum BDNF was analyzed using commercially available enzyme-linked immunosorbent assay (ELISA). The 10-year CVD risk for each participant was computed using the Framingham risk score (FRS). Linear regressions were performed to examine the relationships between serum BDNF with body mass index (BMI), blood pressure (BP), triglycerides (TG), total cholesterol, high-density lipoprotein cholesterol (HDL-C) and glucose. To examine the relationship between serum BDNF and FRS, serum BDNF was categorized into quartiles, and a multiple regression was performed. After adjusting for age, gender and current smoking status, diastolic BP (dBP) (p=0.045) and TG (p=0.015) were found to be significantly associated with serum BDNF. Participants in the highest quartile of serum BDNF had a 3.3 times increase in FRS over those in the lowest quartile. Our findings support the possible regulatory role of BDNF in metabolism and cardiovascular homeostasis among patients with schizophrenia similar to that observed among the non-mentally ill. Serum BDNF not only present itself as a candidate biomarker of schizophrenia but also might be a viable marker of metabolic co-morbidities associated with schizophrenia.
Full Text Available Abstract Background The neurotrophin BDNF has been implicated in the regulation of neuroplasticity, gene expression, and synaptic function in the adult brain, as well as in the pathophysiology of neuropsychiatric disorders and the mechanism of action of antidepressants. Antidepressant treatments have been shown to increase the expression of BDNF mRNA, although the changes measured were found to be different depending on various factors. A few studies only have measured levels of BDNF protein after antidepressant treatments, and poor correlation was found between mRNA and protein changes. We studied the time course of expression of BDNF mRNA and protein during drug treatments, in order to elucidate the temporal profile of regulation of this effector and whether mRNA and protein levels correlate. Rat groups were treated for 1, 2 or 3 weeks with fluoxetine or reboxetine; in additional groups drug treatment was followed by a washout week (3+1. Total BDNF mRNA was measured by Real Time PCR, pro- and mature BDNF proteins were measured by Western blot. Results We found that mature BDNF protein is induced more rapidly than mRNA, by both drugs in hippocampus (weeks 1–2 and by reboxetine in prefrontal/frontal cortex (week 1. The temporal profile of BDNF protein expression was largely inconsistent with that of mRNA, which followed the protein induction and reached a peak at week 3. Conclusion These results suggest that BDNF protein is rapidly elevated by antidepressant treatments by posttranscriptional mechanisms, and that induction of BDNF mRNA is a slower process.
Chen, Jianjun; Deng, Xiao; Zhang, Lin; Zhao, Xiang; Qu, Zehui; Lei, Yang; Lei, Ting
Background Brain derived neurotrophic factor (BDNF) is one of the most important regulatory proteins in the pathophysiology of major depressive disorder (MDD). Increasing numbers of studies have reported the relationship between serum/plasma BDNF and antidepressants (ADs). However, the potential effects of several classes of antidepressants on BDNF concentrations are not well known. Hence, our meta-analyses aims to review the effects of differential antidepressant drugs on peripheral BDNF levels in MDD and make some recommendations for future research. Methods Electronic databases including PubMed, EMBASE, the Cochrane Library, Web of Science, and PsycINFO were searched from 1980 to June 2016. The change in BDNF levels were compared between baseline and post-antidepressants treatment by use of the standardized mean difference (SMD) with 95% confidence intervals (CIs). All statistical tests were two-sided. Results We identified 20 eligible trials of antidepressants treatments for BDNF in MDD. The overall effect size for all drug classes showed that BDNF levels were elevated following a course of antidepressants use. For between-study heterogeneity by stratification analyses, we detect that length of treatment and blood samples are significant effect modifiers for BDNF levels during antidepressants treatment. While both SSRIs and SNRIs could increase the BDNF levels after a period of antidepressant medication treatment, sertraline was superior to other three drugs (venlafaxine, paroxetine or escitalopram) in the early increase of BDNF concentrations with SMD 0.53(95% CI = 0.13–0.93; P = 0.009). Conclusions There is some evidence that treatment of antidepressants appears to be effective in the increase of peripheral BDNF levels. More robust evidence indicates that different types of antidepressants appear to induce differential effects on the BDNF levels. Since sertraline makes a particular effect on BDNF concentration within a short amount of time, there is
Xin, Jian; Ma, Ling; Zhang, Tian-Yi; Yu, Hui; Wang, Yue; Kong, Liang; Chen, Zhe-Yu
Brain-derived neurotrophic factor (BDNF) and its receptor, tropomyosin-related kinase receptor B (TrkB), play a critical role in memory extinction. However, the detailed role of BDNF in memory extinction on the basis of neural circuit has not been fully understood. Here, we aim to investigate the role of BDNF signaling circuit in mediating conditioned taste aversion (CTA) memory extinction of the rats. We found region-specific changes in BDNF gene expression during CTA extinction. CTA extinction led to increased BDNF gene expression in the basolateral amygdala (BLA) and infralimbic prefrontal cortex (IL) but not in the central amygdaloid nucleus (CeA) and hippocampus (HIP). Moreover, blocking BDNF signaling or exogenous microinjection of BDNF into the BLA or IL could disrupt or enhance CTA extinction, which suggested that BDNF signaling in the BLA and IL is necessary and sufficient for CTA extinction. Interestingly, we found that microinjection of BDNF-neutralizing antibody into the BLA could abolish the extinction training-induced BDNF mRNA level increase in the IL, but not vice versa, demonstrating that BDNF signaling is transmitted from the BLA to IL during extinction. Finally, the accelerated extinction learning by infusion of exogenous BDNF in the BLA could also be blocked by IL infusion of BDNF-neutralizing antibody rather than vice versa, indicating that the IL, but not BLA, is the primary action site of BDNF in CTA extinction. Together, these data suggest that BLA-IL circuit regulates CTA memory extinction by identifying BDNF as a key regulator.
Carlos V Melo
Full Text Available BDNF is a pro-survival protein involved in neuronal development and synaptic plasticity. BDNF strengthens excitatory synapses and contributes to LTP, presynaptically, through enhancement of glutamate release, and postsynaptically, via phosphorylation of neurotransmitter receptors, modulation of receptor traffic and activation of the translation machinery. We examined whether BDNF upregulated vesicular glutamate receptor (VGLUT 1 and 2 expression, which would partly account for the increased glutamate release in LTP. Cultured rat hippocampal neurons were incubated with 100 ng/ml BDNF, for different periods of time, and VGLUT gene and protein expression were assessed by real-time PCR and immunoblotting, respectively. At DIV7, exogenous application of BDNF rapidly increased VGLUT2 mRNA and protein levels, in a dose-dependent manner. VGLUT1 expression also increased but only transiently. However, at DIV14, BDNF stably increased VGLUT1 expression, whilst VGLUT2 levels remained low. Transcription inhibition with actinomycin-D or α-amanitine, and translation inhibition with emetine or anisomycin, fully blocked BDNF-induced VGLUT upregulation. Fluorescence microscopy imaging showed that BDNF stimulation upregulates the number, integrated density and intensity of VGLUT1 and VGLUT2 puncta in neurites of cultured hippocampal neurons (DIV7, indicating that the neurotrophin also affects the subcellular distribution of the transporter in developing neurons. Increased VGLUT1 somatic signals were also found 3 h after stimulation with BDNF, further suggesting an increased de novo transcription and translation. BDNF regulation of VGLUT expression was specifically mediated by BDNF, as no effect was found upon application of IGF-1 or bFGF, which activate other receptor tyrosine kinases. Moreover, inhibition of TrkB receptors with K252a and PLCγ signaling with U-73122 precluded BDNF-induced VGLUT upregulation. Hippocampal neurons express both isoforms during
Zucca, Stefano; Valenzuela, C. Fernando
Fetal Alcohol Spectrum Disorder (FASD) is associated with learning and memory alterations that could be, in part, a consequence of hippocampal damage. The CA3 hippocampal subfield is one of the regions affected by ethanol (EtOH), including exposure during the 3rd trimester-equivalent (i.e. neonatal period in rats). However, the mechanism of action of EtOH is poorly understood. In CA3 pyramidal neurons from neonatal rats, dendritic BDNF release causes long-term potentiation of the frequency of...
Makar, T K; Trisler, D; Eglitis, M A; Mouradian, M M; Dhib-Jalbut, S
Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, is protective in animal models of neurodegenerative diseases. However, BDNF has a short half-life and its efficacy in the CNS when delivered peripherally is limited due to the blood-brain barrier. In the present study, bone marrow cells were used as vehicles to deliver the BDNF gene into the CNS. Marrow cells obtained from 6 to 8 week-old SJL/J mice were transduced with BDNF expressing pro-virus. RT-PCR analysis revealed that BDNF mRNA was expressed in transduced but not in non-transduced marrow cells. Additionally, virus transduced marrow cells expressed the BDNF protein (296+/-1.2 unit/ml). BDNF-transduced marrow cells were then transplanted into irradiated mice through the tail vein. Three months post-transplantation, significant increases in BDNF as well as glutamic acid decarboxylase (GAD(67)) mRNA were detected in the brains of BDNF transplanted mice compared to untransplanted animals, indicating biological activity of the BDNF transgene. Thus, bone marrow cells can be used as vehicles to deliver the BDNF gene into the brain with implications for the treatment of neurological diseases.
Zhang, X; Zhu, J; Zhang, K; Liu, T; Zhang, Z
This study was aimed at investigating the expression of brain-derived neurotrophic factor (BDNF) in mesenchymal stem cells (MSCs) modified with recombinant lentivirus bearing BDNF gene. Lentivirus vectors bearing BDNF gene were constructed. MSCs were isolated from rats and cultured. The lentiviral vectors containing BDNF gene were transfected into the MSCs, and BDNF gene and protein expressions were monitored with enhanced green fluorescent protein (EGFP). RT-PCR and Western blot were used to measure gene and protein expressions, respectibvely in MSCs, MSCs-EGFP and MSCs-EGFP-BDNF groups. Green fluorescence assay confirmed successful transfection of BDNF gene recombinant lentivirus into MSCs. RT-PCR and Western blot revealed that BDNF gene and protein expressions in the MSCs-EGFP-BDNF group were significantly higher than that in MSCs group and MSCs-EGFP group. There were no statistically signiﬁcant differences in gene expression between MSCs and MSCs-EGFP groups. MSCs can over-express BDNF when transfected with recombinant lentivirus bearing BDNF gene.
Aliperti, Vincenza; Donizetti, Aldo
Brain-derived neurotrophic factor (BDNF) is a neurotrophin family member that is highly expressed and widely distributed in the brain. BDNF is critical for neural survival and plasticity both during development and in adulthood, and dysfunction in its signaling may contribute to a number of neurodegenerative disorders. Deep understanding of the BDNF-activated molecular cascade may thus help to find new biomarkers and therapeutic targets. One interesting direction is related to the early phase of BDNF-dependent gene expression regulation, which is responsible for the activation of selective gene programs that lead to stable functional and structural remodeling of neurons. Immediate-early coding genes activated by BDNF are under investigation, but the involvement of the non-coding RNAs is largely unexplored, especially the long non-coding RNAs (lncRNAs). lncRNAs are emerging as key regulators that can orchestrate different aspects of nervous system development, homeostasis, and plasticity, making them attractive candidate markers and therapeutic targets for brain diseases. We used microarray technology to identify differentially expressed lncRNAs in the immediate response phase of BDNF stimulation in a neuronal cell model. Our observations on the putative functional role of lncRNAs provide clues to their involvement as master regulators of gene expression cascade triggered by BDNF.
Kim M Gerecke
Full Text Available Exercise has been demonstrated to potently protect substantia nigra pars compacta (SN dopaminergic neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP-induced neurotoxicity. One mechanism proposed to account for this neuroprotection is the upregulation of neurotrophic factors. Several neurotrophic factors, including Brain Derived Neurotrophic Factor (BDNF, have been shown to upregulate in response to exercise. In order to determine if exercise-induced neuroprotection is dependent upon BDNF, we compared the neuroprotective effects of voluntary exercise in mice heterozygous for the BDNF gene (BDNF+/- with strain-matched wild-type (WT mice. Stereological estimates of SNpc DA neurons from WT mice allowed 90 days exercise via unrestricted running demonstrated complete protection against the MPTP-induced neurotoxicity. However, BDNF+/- mice allowed 90 days of unrestricted exercise were not protected from MPTP-induced SNpc DA neuron loss. Proteomic analysis comparing SN and striatum from 90 day exercised WT and BDNF+/- mice showed differential expression of proteins related to energy regulation, intracellular signaling and trafficking. These results suggest that a full genetic complement of BDNF is critical for the exercise-induced neuroprotection of SNpc DA neurons.
Schjetnan, Andrea Gómez-Palacio; Escobar, Martha L
Changes in synaptic efficacy and morphology have been proposed as mechanisms underlying learning and memory processes. In our previous studies, high frequency stimulation (HFS) sufficient to induce LTP at the hippocampal mossy fiber (MF) pathway, leads to MF synaptogenesis, in a prominent contralateral form, at the stratum oriens of hippocampal CA3 area. Recently we reported that acute intrahippocampal microinfusion of BDNF induces a lasting potentiation of synaptic efficacy at the MF projection accompanied by a structural reorganization at the CA3 area within the stratum oriens region in a prominent ipsilateral form. It is considered that the capacity of synapses to express plastic changes is itself subject to variation dependent on previous experience. Here we used intrahippocampal microinfusion of BDNF to analyze its effects on functional and structural synaptic plasticity induced by subsequent mossy fiber HFS sufficient to induce LTP in adult rats, in vivo. Our results show that BDNF modifies the ability of the MF pathway to present LTP by HFS. Moreover BDNF modified the structural reorganization pattern produced by HFS, presenting a balanced bilateral appearance. Microinfusion of K252a blocks the functional and morphological effects produced by BDNF, revealing that the BDNF modulation is dependent on its TrkB receptor activation. These findings support the idea that BDNF actions modify subsequent synaptic plasticity; a homeostatic mechanism thought to be essential for synaptic integration among prolonged temporal domains in the adult mammalian brain.
Luo, Liu; Liu, Xiao-Long; Mu, Rong-Hao; Wu, Yong-Jing; Liu, Bin-Bin; Geng, Di; Liu, Qing; Yi, Li-Tao
Brain-derived neurotrophic factor (BDNF) plays a key role in the regulation of depression in the brain. Recently, increasing studies have focused on the antidepressant-like mechanism of BDNF and its downstream signaling pathway. A previous study has shown that asiaticoside produced an antidepressant-like action in the mouse tail suspension test and forced swimming test. However, the neurotrophic mechanism that is affected by asiaticoside is unclear. Our present study aimed to verify whether asiaticoside produces an antidepressant-like effect through the activation of BDNF signaling in chronic unpredictable mild stress (CUMS). The results showed that mice treated with asiaticoside for four weeks reversed the decreased sucrose preference and increased immobility time that was observed in CUMS mice. In addition, we found that asiaticoside up-regulated BDNF, PSD-95 and synapsin I expression only in the hippocampus but not in the frontal cortex in both non-stressed and CUMS mice. However, K252a, an inhibitor of BDNF receptor tropomyosin-related kinase receptor B (TrkB), completely abolished the antidepressant-like effect of asiaticoside. Moreover, the expression of hippocampal BDNF, PSD-95 and synapsin I that had increased with asiaticoside also declined with K252a pretreatment. In conclusion, our study implies that it is possible that asiaticoside exerts its antidepressant-like action by activating BDNF signaling in the hippocampus.
Zhang, Yang; Gu, Fenghua; Chen, Jia; Dong, Wenxin
Stress activates the hypothalamo-pituitary-adrenal (HPA) axis, regulates the expression of brain-derived neurotrophic factor (BDNF) in the brain, and mediates mood. Antidepressants alleviate stress and up-regulate BDNF gene expression. In this study, we investigated the effect of chronic unpredictable mild stress (CUMS) and the different kinds of antidepressant treatments on the HPA axis and the BDNF expression in the rat brain. Adult Wistar male rats were exposed to a six-week CUMS procedure and received different antidepressant treatments including venlafaxine, mirtazapine, and fluoxetine. Immunohistochemistry and real-time PCR were used to measure BDNF expression levels in the rat brain, and ELISAs were used to investigate the plasma corticosterone (CORT) and adrenocorticotropic hormone (ACTH) levels. CUMS significantly decreased the BDNF protein level in the DG, CA1, and CA3 of the hippocampus and increased plasma CORT level. Chronic antidepressant treatments all significantly increased BDNF protein levels in the hippocampus and the pre-frontal cortex. In addition, venlafaxine and mirtazapine inhibited the increase of plasma CORT level. These results suggested that an increase in the BDNF level in the brain could be a pivotal mechanism of various antidepressants to exert their therapeutic effects.
Full Text Available Pituitary adenylate cyclase-activating polypeptide (PACAP exerts neurotrophic activities including modulation of synaptic plasticity and memory, hippocampal neurogenesis, and neuroprotection, most of which are shared with brain-derived neurotrophic factor (BDNF. Therefore, the aim of this study was to compare morphological effects of PACAP and BDNF on primary cultured hippocampal neurons. At days in vitro (DIV 3, PACAP increased neurite length and number to similar levels by BDNF, but vasoactive intestinal polypeptide showed much lower effects. In addition, PACAP increased axon, but not dendrite, length, and soma size at DIV 3 similarly to BDNF. The PACAP antagonist PACAP6-38 completely blocked the PACAP-induced increase in axon, but not dendrite, length. Interestingly, the BDNF-induced increase in axon length was also inhibited by PACAP6-38, suggesting a mechanism involving PACAP signaling. K252a, a TrkB receptor inhibitor, inhibited axon outgrowth induced by PACAP and BDNF without affecting dendrite length. These results indicate that in primary cultured hippocampal neurons, PACAP shows morphological actions via its cognate receptor PAC1, stimulating neurite length and number, and soma size to a comparable extent as BDNF, and that the increase in total neurite length is ascribed to axon outgrowth.
Wei LI; Wen-Qin CAI; Cheng-Ren LI
Objective To explore repair of spinal cord injury by neural stem cells (NSCs) modified with brain derived neurotrophic factor (BDNF) gene (BDNF-NSCs) in rats. Methods Neural stem cells modified with BDNF gene were transplanted into the complete transection site of spinal cord at the lumbar 4 (L4) level in rats. Motor function of rats'hind limbs was observed and HE and X-gal immunocytochemical staining, in situ hybridization, and retrograde HRP tracing were also performed. Results BDNF-NSCs survived and integrated well with host spinal cord. In the transplant group, some X-gal positive, NF-200 positive, GFAP positive, BDNF positive, and BDNF mRNA positive cells, and many NF-200 positive nerve fibers were observed in the injury site. Retrograde HRP tracing through sciatic nerve showed some HRP positive cells and nerve fibers near the rostral side of the injury one month after transplant and with time, they increased in number. Examinations on rats' motor function and behavior demonstrated that motor function of rats' hind limbs improved better in the transplant group than the injury group. Conclusion BDNF-NSCs can survive, differentiate,and partially integrate with host spinal cord, and they significantly ameliorate rats ' motor function of hind limbs, indicating their promising role in repairing spinal cord injury.
Haile, C N; Murrough, J W; Iosifescu, D V; Chang, L C; Al Jurdi, R K; Foulkes, A; Iqbal, S; Mahoney, J J; De La Garza, R; Charney, D S; Newton, T F; Mathew, S J
Ketamine produces rapid antidepressant effects in treatment-resistant depression (TRD), but the magnitude of response varies considerably between individual patients. Brain-derived neurotrophic factor (BDNF) has been investigated as a biomarker of treatment response in depression and has been implicated in the mechanism of action of ketamine. We evaluated plasma BDNF and associations with symptoms in 22 patients with TRD enrolled in a randomized controlled trial of ketamine compared to an anaesthetic control (midazolam). Ketamine significantly increased plasma BDNF levels in responders compared to non-responders 240 min post-infusion, and Montgomery-Åsberg Depression Rating Scale (MADRS) scores were negatively correlated with BDNF (r=-0.701, p = 0.008). Plasma BDNF levels at 240 min post-infusion were highly negatively associated with MADRS scores at 240 min (r = -0.897, p=.002), 24 h (r = -0.791, p = 0.038), 48 h (r = -0.944, p = 0.001) and 72 h (r = -0.977, p = 0.010). No associations with BDNF were found for patients receiving midazolam. These data support plasma BDNF as a peripheral biomarker relevant to ketamine antidepressant response.
Clevenger, Amy C; Salcedo, Ernesto; Jones, Kevin R; Restrepo, Diego
The neurotrophin brain-derived neurotrophic factor (BDNF) has been implicated in the generation and differentiation of new olfactory sensory neurons (OSNs) and in the regulation of branching of OSN axons in their target glomeruli. However, previous reports of BDNF mRNA and protein expression in olfactory epithelium and olfactory bulb (OB) have been inconsistent, raising questions on the proposed roles for BDNF. Here, we report on beta-galactosidase (beta-gal) expression in adult gene-targeted mice where the BDNF promoter drives expression of the Escherichia coli lacZ gene (BDNF(lacZneo) mice). We find that beta-gal is expressed in a small subset of OSNs with axons that reach the olfactory nerve layers throughout the OB. In the OB, we find expression of beta-gal in gamma-aminobutyric acidergic but not dopaminergic periglomerular cells and external tufted cells and in interneurons located in the mitral cell layer. Our results are inconsistent with the regulation of generation and differentiation of new OSNs elicited by the release of BDNF from horizontal basal cells. The results are consistent with a role for BDNF in competitive branching of OSN axons within the glomeruli of the OB.
Edelmann, Elke; Lessmann, Volkmar; Brigadski, Tanja
Overwhelming evidence collected since the early 1990's strongly supports the notion that BDNF is among the key regulators of synaptic plasticity in many areas of the mammalian central nervous system. Still, due to the extremely low expression levels of endogenous BDNF in most brain areas, surprisingly little data i) pinpointing pre- and postsynaptic release sites, ii) unraveling the time course of release, and iii) elucidating the physiological levels of synaptic activity driving this secretion are available. Likewise, our knowledge regarding pre- and postsynaptic effects of endogenous BDNF at the single cell level in mediating long-term potentiation still is sparse. Thus, our review will discuss the data currently available regarding synaptic BDNF secretion in response to physiologically relevant levels of activity, and will discuss how endogenously secreted BDNF affects synaptic plasticity, giving a special focus on spike timing-dependent types of LTP and on mossy fiber LTP. We will attempt to open up perspectives how the remaining challenging questions regarding synaptic BDNF release and action might be addressed by future experiments. This article is part of the Special Issue entitled 'BDNF Regulation of Synaptic Structure, Function, and Plasticity'.
Pizarro, Jose M; Chang, Wenling E; Bah, Mariama J; Wright, Linnzi K M; Saviolakis, George A; Alagappan, Arun; Robison, Christopher L; Shah, Jinesh D; Meyerhoff, James L; Cerasoli, Douglas M; Midboe, Eric G; Lumley, Lucille A
The highly toxic organophosphorus compound VX [O-ethyl S-[2-(diisopropylamino)ethyl]methylphosphonate] is an irreversible inhibitor of the enzyme acetylcholinesterase (AChE). Prolonged inhibition of AChE increases endogenous levels of acetylcholine and is toxic at nerve synapses and neuromuscular junctions. We hypothesized that repeated exposure to sublethal doses of VX would affect genes associated with cell survival, neuronal plasticity, and neuronal remodeling, including brain-derived neurotrophic factor (BDNF). We examined the time course of BDNF expression in C57BL/6 mouse brain following repeated exposure (1/day × 5 days/week × 2 weeks) to sublethal doses of VX (0.2 LD(50) and 0.4 LD(50)). BDNF messenger RNA expression was significantly (p VX exposure. BDNF protein expression, however, was only increased in the CA3 region of the hippocampus. Whether increased BDNF in response to sublethal doses of VX exposure is an adaptive response to prevent cellular damage or a precursor to impending brain damage remains to be determined. If elevated BDNF is an adaptive response, exogenous BDNF may be a potential therapeutic target to reduce the toxic effects of nerve agent exposure.
Gray, J D; Rubin, T G; Kogan, J F; Marrocco, J; Weidmann, J; Lindkvist, S; Lee, F S; Schmidt, E F; McEwen, B S
Genetic susceptibility and environmental factors (such as stress) can interact to affect the likelihood of developing a mood disorder. Stress-induced changes in the hippocampus have been implicated in mood disorders, and mutations in several genes have now been associated with increased risk, such as brain-derived neurotrophic factor (BDNF). The hippocampus has important anatomical subdivisions, and pyramidal neurons of the vulnerable CA3 region show significant remodeling after chronic stress, but the mechanisms underlying their unique plasticity remain unknown. This study characterizes stress-induced changes in the in vivo translating mRNA of this cell population using a CA3-specific enhanced green fluorescent protein (EGFP) reporter fused to the L10a large ribosomal subunit (EGFPL10a). RNA-sequencing after isolation of polysome-bound mRNAs allows for cell-type-specific, genome-wide characterization of translational changes after stress. The data demonstrate that acute and chronic stress produce unique translational profiles and that the stress history of the animal can alter future reactivity of CA3 neurons. CA3-specific EGFPL10a mice were then crossed to the stress-susceptible BDNF Val66Met mouse line to characterize how a known genetic susceptibility alters both baseline translational profiles and the reactivity of CA3 neurons to stress. Not only do Met allele carriers exhibit distinct levels of baseline translation in genes implicated in ion channel function and cytoskeletal regulation, but they also activate a stress response profile that is highly dissimilar from wild-type mice. Closer examination of genes implicated in the mechanisms of neuroplasticity, such as the NMDA and AMPA subunits and the BDNF pathway, reveal how wild-type mice upregulate many of these genes in response to stress, but Met allele carriers fail to do so. These profiles provide a roadmap of stress-induced changes in a genetically homogenous population of hippocampal neurons and
Keifer, Joyce; Sabirzhanov, Boris E; Zheng, Zhaoqing; Li, Wei; Clark, Timothy G
The tolloid/bone morphogenetic protein-1 family of metalloproteinases have an important role in the regulation of embryonic pattern formation and tissue morphogenesis. Studies suggest that they participate in mechanisms of synaptic plasticity in adults, but very little is known about their function. Recently, we isolated a reptilian ortholog of the tolloid gene family designated turtle tolloid-like gene (tTll). Here, we examined the role of tTLL in an in vitro model of eyeblink classical conditioning using an isolated brainstem preparation to assess its role in synaptic plasticity during conditioning. Analysis by real-time reverse transcription-PCR shows that an extracellularly secreted form of tTLL, tTLLs, is transiently expressed in the early stages of conditioning during conditioned response acquisition, whereas a cytosolic form, tTLLc, is not. Short interfering RNA (siRNA)-directed gene knockdown and rescue of tTLL expression demonstrate that it is required for conditioning. Significantly, we show that tTLLs cleaves the precursor proBDNF into mature BDNF in cleavage assay studies, and application of recombinant tTLLs protein alone to preparations results in induction of mature BDNF expression. The mature form of BDNF is minimally expressed in preparations treated with anti-tTLL siRNA, and the synaptic incorporation of both GluR1- and GluR4-containing AMPA receptors is significantly reduced, resulting in suppression of conditioning. This is the first study to demonstrate that expression of an extracellularly secreted tolloid-like metalloproteinase is regulated in the early stages of classical conditioning and functions in the conversion of proBDNF to mature BDNF. The mature form of BDNF is required for synaptic delivery of AMPA receptors and acquisition of conditioned responses.
Full Text Available Brain-derived neurotrophic factor (BDNF through TrkB activation is central for brain functioning. Since the demonstration that plasmin is able to process pro-BDNF to mature BDNF and that these two forms have opposite effects on neuronal survival and plasticity, a particular attention has been paid to the link between tissue plasminogen activator (tPA/plasmin system and BDNF metabolism. However, t-PA via its action on different N-methyl-D-aspartate (NMDA receptor subunits is also considered as a neuromodulator of glutamatergic transmission. In this context, the aim of our study was to investigate the effect of recombinant (rt-PA administration on brain BDNF metabolism in rats. In the hippocampus, we found that rt-PA (10 mg/kg administration induced a progressive increase in mature BDNF levels associated with TrkB activation. In order to delineate the mechanistic involved, plasmin activity was assessed and its inhibition was attempted using tranexamic acid (30 or 300 mg/kg, i.v. while NMDA receptors were antagonized with MK801 (0.3 or 3 mg/kg, i.p. in combination with rt-PA treatment. Our results showed that despite a rise in rt-PA activity, rt-PA administration failed to increase hippocampal plasmin activity suggesting that the plasminogen/plasmin system is not involved whereas MK801 abrogated the augmentation in mature BDNF levels observed after rt-PA administration. All together, our results show that rt-PA administration induces increase in hippocampal mature BDNF expression and suggests that rt-PA contributes to the control of brain BDNF synthesis through a plasmin-independent potentiation of NMDA receptors signaling.
Dominik A Moser
Full Text Available It is known that increased circulating glucocorticoids in the wake of excessive, chronic, repetitive stress increases anxiety and impairs Brain-Derived Neurotrophic Factor (BDNF signaling. Recent studies of BDNF gene methylation in relation to maternal care have linked high BDNF methylation levels in the blood of adults to lower quality of received maternal care measured via self-report. Yet the specific mechanisms by which these phenomena occur remain to be established. The present study examines the link between methylation of the BDNF gene promoter region and patterns of neural activity that are associated with maternal response to stressful versus non-stressful child stimuli within a sample that includes mothers with interpersonal violence-related PTSD (IPV-PTSD. 46 mothers underwent fMRI. The contrast of neural activity when watching children-including their own-was then correlated to BDNF methylation. Consistent with the existing literature, the present study found that maternal BDNF methylation was associated with higher levels of maternal anxiety and greater childhood exposure to domestic violence. fMRI results showed a positive correlation of BDNF methylation with maternal brain activity in the anterior cingulate (ACC, and ventromedial prefrontal cortex (vmPFC, regions generally credited with a regulatory function toward brain areas that are generating emotions. Furthermore we found a negative correlation of BDNF methylation with the activity of the right hippocampus. Since our stimuli focus on stressful parenting conditions, these data suggest that the correlation between vmPFC/ACC activity and BDNF methylation may be linked to mothers who are at a disadvantage with respect to emotion regulation when facing stressful parenting situations. Overall, this study provides evidence that epigenetic signatures of stress-related genes can be linked to functional brain regions regulating parenting stress, thus advancing our understanding of
Full Text Available Background: The neurotrophins nerve growth factor (NGF and brain-derived neurotrophic factor (BDNF is a family of polypeptides that play critical role during neuronal development, appear to mediate protective role on neurorepair in ischemic stroke. Naturally in adult brain neurorepair process consist of: angiogenesis, neurogenesis, and neuronal plasticity, it can also be stimulated by endogenous neurorepair. In this study we observed correlation between NGF and BDNF ischemic stroke patient’s onset: 7-30 and over 30 days. Methods: This is cross sectional study on 46 subjects aged 38 – 74 years old with ischemic stroke from The Indonesian Central Hospital of Army Gatot Subroto Jakarta. Diagnosis of ischemic stroke was made using clinical examination and magnetic resonance imaging (MRI by neurologist. Subjects were divided into 2 groups based on stroke onset: 7 – 30 days (Group A: 19 subjects and > 30 days (Group B: 27 Subjects. Serum NGF levels were measured with ELISA method and BDNF levels were measured using multiplex method with Luminex Magpix. Results: Levels of NGF and BDNF were significantly different between onset group A and B (NGF p= 0.022, and BDNF p=0.008, with mean levels NGF in group A higher than group B, indicating that BDNF levels is lower in group A than group B. There was no significant correlation between NGF and BDNF levels in all groups. Conclusion: The variations in neurotrophic factor levels reflect an endogenous attempt at neuroprotection against biochemical and molecular changes after ischemic stroke. NGF represents an early marker of brain injury while BDNF recovery is most prominent during the first 14 days after onsite but continuous for more than 30 days. There is no significant correlation between NGF and BDNF in each group.
Briz, Victor; Hsu, Yu-Tien; Li, Yi; Lee, Erin; Bi, Xiaoning; Baudry, Michel
Memory consolidation has been suggested to be protein synthesis dependent. Previous data indicate that BDNF-induced dendritic protein synthesis is a key event in memory formation through activation of the mammalian target of rapamycin (mTOR) pathway. BDNF also activates calpain, a calcium-dependent cysteine protease, which has been shown to play a critical role in learning and memory. This study was therefore directed at testing the hypothesis that calpain activity is required for BDNF-stimulated local protein synthesis, and at identifying the underlying molecular mechanism. In rat hippocampal slices, cortical synaptoneurosomes, and cultured neurons, BDNF-induced mTOR pathway activation and protein translation were blocked by calpain inhibition. BDNF treatment rapidly reduced levels of hamartin and tuberin, negative regulators of mTOR, in a calpain-dependent manner. Treatment of brain homogenates with purified calpain-1 and calpain-2 truncated both proteins. BDNF treatment increased phosphorylation of both Akt and ERK, but only the effect on Akt was blocked by calpain inhibition. Levels of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), a phosphatase that inactivates Akt, were decreased following BDNF treatment, and calpain inhibition reversed this effect. Calpain-2, but not calpain-1, treatment of brain homogenates resulted in PTEN degradation. In cultured cortical neurons, knockdown of calpain-2, but not calpain-1, by small interfering RNA completely suppressed the effect of BDNF on mTOR activation. Our results reveal a critical role for calpain-2 in BDNF-induced mTOR signaling and dendritic protein synthesis via PTEN, hamartin, and tuberin degradation. This mechanism therefore provides a link between proteolysis and protein synthesis that might contribute to synaptic plasticity.
Ida-Yonemochi, Hiroko; Yamada, Yurie; Yoshikawa, Hiroyuki
Brain-derived neurotrophic factor (BDNF), which is released due to nerve injury, is known to promote the natural healing of injured nerves. It is often observed that damage of mandibular canal induces local sclerotic changes in alveolar bone. We reported that peripheral nerve injury promotes the local production of BDNF; therefore, it was possible to hypothesize that peripheral nerve injury affects sclerotic changes in the alveolar bone. This study aimed to evaluate the effect of BDNF on osteogenesis using in vitro osteoblast-lineage cell culture and an in vivo rat osteotomy model. MC3T3-E1 cells were cultured with BDNF and were examined for cell proliferative activity, chemotaxis and mRNA expression levels of osteoblast differentiation markers. For in vivo study, inferior alveolar nerve (IAN) injury experiments and mandibular cortical osteotomy were performed using a rat model. In the osteotomy model, exogenous BDNF was applied to bone surfaces after corticotomy of the mandible, and we morphologically analyzed the new bone formation. As a result, mRNA expression of osteoblast differentiation marker, osteocalcin, was significantly increased by BDNF, although cell proliferation and migration were not affected. In the in vivo study, osteopontin-positive new bone formation was significantly accelerated in the BDNF-grafted groups, and active bone remodeling, involving trkB-positive osteoblasts and osteocytes, continued after 28 days. In conclusion, BDNF stimulated the differentiation of MC3T3-E1 cells and it promoted new bone formation and maturation. These results suggested that local BDNF produced by peripheral nerve injury contributes to accelerating sclerotic changes in the alveolar bone. PMID:28072837
Rodier, Marion; Prigent-Tessier, Anne; Béjot, Yannick; Jacquin, Agnès; Mossiat, Claude; Marie, Christine; Garnier, Philippe
Brain-derived neurotrophic factor (BDNF) through TrkB activation is central for brain functioning. Since the demonstration that plasmin is able to process pro-BDNF to mature BDNF and that these two forms have opposite effects on neuronal survival and plasticity, a particular attention has been paid to the link between tissue plasminogen activator (tPA)/plasmin system and BDNF metabolism. However, t-PA via its action on different N-methyl-D-aspartate (NMDA) receptor subunits is also considered as a neuromodulator of glutamatergic transmission. In this context, the aim of our study was to investigate the effect of recombinant (r)t-PA administration on brain BDNF metabolism in rats. In the hippocampus, we found that rt-PA (10 mg/kg) administration induced a progressive increase in mature BDNF levels associated with TrkB activation. In order to delineate the mechanistic involved, plasmin activity was assessed and its inhibition was attempted using tranexamic acid (30 or 300 mg/kg, i.v.) while NMDA receptors were antagonized with MK801 (0.3 or 3 mg/kg, i.p.) in combination with rt-PA treatment. Our results showed that despite a rise in rt-PA activity, rt-PA administration failed to increase hippocampal plasmin activity suggesting that the plasminogen/plasmin system is not involved whereas MK801 abrogated the augmentation in mature BDNF levels observed after rt-PA administration. All together, our results show that rt-PA administration induces increase in hippocampal mature BDNF expression and suggests that rt-PA contributes to the control of brain BDNF synthesis through a plasmin-independent potentiation of NMDA receptors signaling.
Mackowiak, Marzena; O'Neill, Michael J; Hicks, Caroline A; Bleakman, David; Skolnick, Phil
AMPA receptor activation has been demonstrated to increase the neuronal expression of brain derived neurotrophic factor (BDNF). In the present study, we investigated the effect of a novel AMPA receptor potentiator (LY404187) and its active isomer (LY451646) on the expression of BDNF protein and mRNA, as well as TrkB mRNA in rat hippocampus. LY404187 administered for 7 days (1 mg/kg) significantly increased the number of BDNF immunopositive cells in the dentate gyrus, but not other hippocampal subfields. Chronic treatment (7 days) with LY451646 (0.5 mg/kg, comparable to 1 mg/kg of LY404187) increased the level of both BDNF and TrkB mRNA expression in the dentate gyrus, CA3 and CA4 of the hippocampus. However, chronic treatment with lower doses of LY451646 (0.125 and 0.25 mg/kg) decreased the level of BDNF and TrkB mRNA in hippocampus, whilst the highest used dose of LY451646 (1 mg/kg) had no effect on BDNF and TrkB mRNA in hippocampus. In contrast, acute treatment with LY451646 produced an increase in BDNF mRNA levels at doses of 0.125 and 0.25 mg/kg in the hippocampus (CA4, CA3 and dentate gyrus, but not in CA1). LY451646 at 0.5 mg/kg had no effect, but at 1.0 mg/kg decreased the level of BDNF mRNA in hippocampus. Acute treatment with LY451646 did not affect the TrkB receptor mRNA levels in hippocampus. Our results demonstrate that biarylpropylsulfonamide AMPA receptor potentiators are capable of modulating the expression of BDNF and TrkB mRNA in a dose- and time-dependent manner. The increase in both BDNF protein and mRNA expression in the dentate gyrus but not in CA1 indicates a specific role of AMPA receptors in the regulation of BDNF expression in this hippocampal subfield. The regulation of BDNF expression by biarylpropylsulfonamids such as LY451646 may have important therapeutical implications for this class of molecule in the treatment of depression and other CNS disorders.
Ji, Qing; Lu, Jufei; Chao, Qing; Zhang, Yan; Zhang, Meijing; Gu, Minghong; Xu, Mingliang
The rice indica/japonica hybrid shows strong heterosis. However, such inter-subspecific hybrid can't be directly used in rice production due to its low spikelet fertility. The S5 locus was proved to be associated with fertility of indica/japonica hybrid and its S5n allele from wide-compatibility variety (WCV) is capable to overcome fertility barrier. In the present study, we reported the causal sites in the S5 locus responsible for compatibility of indica/japonica hybrid. Fine-mapping of the S5 locus using the 11 test-cross families pinpoints a candidate S5 locus encoding aspartic protease (Asp). Intragenic recombination within the Asp gene happened in a number of recombinants, resulting in chimeric S5j-S5n alleles. Just like S5n, the chimeric S5j-S5n allele displayed higher spikelet fertility when combined with the S5i allele. In the complementary test, however, the S5n allele from WCVs failed to enhance fertilities of the indica/japonica hybrids. Compared to both indica and japonica varieties, all nine WCVs from different resources are characterized with a 136 bp deletion in the Asp N-terminus, which probably renders the S5n allele non-functional. Furthermore, an A/C polymorphic site is detected 1,233 bp downstream of the Asp start codon. The heterozygous A/C site of the Asp gene in indica/japonica hybrid is believed to be the casual factor to cause partial sterility. The functional makers based on the two polymorphic sites will be broadly used in developing wide-compatibility rice varieties.
Blockade of Cannabinoid CB1 receptor attenuates the acquisition of morphine-induced conditioned place preference along with a downregulation of ERK, CREB phosphorylation, and BDNF expression in the nucleus accumbens and hippocampus.
Zhang, Jianbo; Wang, Na; Chen, Bo; Wang, Yi'nan; He, Jing; Cai, Xintong; Zhang, Hongbo; Wei, Shuguang; Li, Shengbin
Cannabinoid CB1 receptor (CB1R) is highly expressed in the mesocorticolimbic system and associated with drug craving and relapse. Clinical trials suggest that CB1R antagonists may represent new therapies for drug addiction. However, the downstream signaling of CB1R is not fully elucidated. In the present study, we investigated the relationship between CB1R and the extracellular signal-regulated kinase (ERK), cAMP response element-binding protein (CREB), brain-derived neurotrophic factor (BDNF) signaling in the nucleus accumbens (NAc) and hippocampus in morphine-induced conditioned place preference (CPP), which is used to assess the morphine-induced reward memory. The protein level of CB1R, ERK, CREB, and BDNF were detected by western blotting. Additionally, a CB1R antagonist, AM251, was used to study whether blockade of CB1R altered the CPP and above-mentioned molecules. We found an increase of CB1R expression in the NAc and hippocampus of the mice following morphine CPP, but not those after repeated morphine in home cage without context exposure (NO-CPP). Both morphine CPP and NO-CPP induced an upregulation of ERK, CREB phosphorylation and BDNF expression. Furthermore, pretreatment with AM251 before morphine attenuated the CPP acquisition and CB1R expression as well as the activation of ERK-CREB-BDNF cascade. Collectively, these findings demonstrate that (1) Repeated morphine with context exposures but not merely the pharmacological effects of morphine increased CB1R expression both in the NAc and hippocampus. (2) CB1R antagonist mediated blockade of ERK-CREB-BDNF signaling activation in the NAc and hippocampus may be an important mechanism underlying the attenuation of morphine CPP.
Sakata, Kazuko; Woo, Newton H; Martinowich, Keri; Greene, Joshua S; Schloesser, Robert J; Shen, Liya; Lu, Bai
Transcription of Bdnf is controlled by multiple promoters, which drive expression of multiple transcripts encoding for the same protein. Promoter IV contributes significantly to activity-dependent brain-derived neurotrophic factor (BDNF) transcription. We have generated promoter IV mutant mice (BDNF-KIV) by inserting a GFP-STOP cassette within the Bdnf exon IV locus. This genetic manipulation results in disruption of promoter IV-mediated Bdnf expression. BDNF-KIV animals exhibited significant deficits in GABAergic interneurons in the prefrontal cortex (PFC), particularly those expressing parvalbumin, a subtype implicated in executive function and schizophrenia. Moreover, disruption of promoter IV-driven Bdnf transcription impaired inhibitory but not excitatory synaptic transmission recorded from layer V pyramidal neurons in the PFC. The attenuation of GABAergic inputs resulted in an aberrant appearance of spike-timing-dependent synaptic potentiation (STDP) in PFC slices derived from BDNF-KIV, but not wild-type littermates. These results demonstrate the importance of promoter IV-dependent Bdnf transcription in GABAergic function and reveal an unexpected regulation of STDP in the PFC by BDNF.
LIU Zhaohui; MA Dongliang; FENG Gaifeng; MA Yanbing; HU Haitao
The human brain-derived neurotrophic factor (hBDNF) gene was cloned by polymerase chain reaction and the recombinant adeno-associated viral vector inserted with hBDNF gene (AAV-hBDNF) was constructed. Cultured rat hippocampal neurons were treated with Aβ25-35 and serued as the experimental Aβ-induced neuronal damage model (AD model), and the AD model was infected with AAV-hBDNF to explore neuroprotective effects of expression of BDNF. Cell viability was assayed by MTT. The expression of bcl-2 anti-apoptosis protein was detected by immunocytochemical staining. The change of intracellular free Ca ion ([Ca2+]i) was measured by laser scanning confocal microscopy. The results showed that BDNF had protective effects against Aβ-induced neuronal damage. The expression of the bcl-2 anti-apoptosis protein was raised significantly and the balance of [Ca2+]i was maintained in the AAV-hBDNF treatment group as compared with AD model group. These data suggested that recombinant AAV mediated a stable expression of hBDNF in cultured hippocampal neurons and resulted in significant neuron protective effects in AD model. The BDNF may reduce neuron apoptosis through increasing the expression of the bcl-2 anti-apoptosis protein and inhibiting intracellular calcium overload. The viral vector-mediated gene expression of BDNF may pave the way of a novel therapeutic strategy for the treatment of neurodegenerative diseases such as Alzheimer's disease.
Frias, Bárbara; Santos, João; Morgado, Marlene; Sousa, Mónica Mendes; Gray, Susannah M Y; McCloskey, Karen D; Allen, Shelley; Cruz, Francisco; Cruz, Célia Duarte
Neurogenic detrusor overactivity (NDO) is a well known consequence of spinal cord injury (SCI), recognizable after spinal shock, during which the bladder is areflexic. NDO emergence and maintenance depend on profound plastic changes of the spinal neuronal pathways regulating bladder function. It is well known that neurotrophins (NTs) are major regulators of such changes. NGF is the best-studied NT in the bladder and its role in NDO has already been established. Another very abundant neurotrophin is BDNF. Despite being shown that, acting at the spinal cord level, BDNF is a key mediator of bladder dysfunction and pain during cystitis, it is presently unclear if it is also important for NDO. This study aimed to clarify this issue. Results obtained pinpoint BDNF as an important regulator of NDO appearance and maintenance. Spinal BDNF expression increased in a time-dependent manner together with NDO emergence. In chronic SCI rats, BDNF sequestration improved bladder function, indicating that, at later stages, BDNF contributes NDO maintenance. During spinal shock, BDNF sequestration resulted in early development of bladder hyperactivity, accompanied by increased axonal growth of calcitonin gene-related peptide-labeled fibers in the dorsal horn. Chronic BDNF administration inhibited the emergence of NDO, together with reduction of axonal growth, suggesting that BDNF may have a crucial role in bladder function after SCI via inhibition of neuronal sprouting. These findings highlight the role of BDNF in NDO and may provide a significant contribution to create more efficient therapies to manage SCI patients.
Giampà, Carmela; Montagna, Elena; Dato, Clemente; Melone, Mariarosa A B; Bernardi, Giorgio; Fusco, Francesca Romana
Loss of huntingtin-mediated BDNF gene transcription has been shown to occur in HD and thus contribute to the degeneration of the striatum. Several studies have indicated that an increase in BDNF levels is associated with neuroprotection and amelioration of neurological signs in animal models of HD. In a recent study, an increase in BDNF mRNA and protein levels was recorded in mice administered recombinant BDNF peripherally. Chronic, indwelling osmotic mini-pumps containing either recombinant BDNF or saline were surgically placed in R6/2 or wild-type mice from 4 weeks of age until euthanasia. Neurological evaluation (paw clasping, rotarod performance, locomotor activity in an open field) was performed. After transcardial perfusion, histological and immunohistochemical studies were performed. We found that BDNF- treated R6/2 mice survived longer and displayed less severe signs of neurological dysfunction than the vehicle treated ones. Primary outcome measures such as brain volume, striatal atrophy, size and morphology of striatal neurons, neuronal intranuclear inclusions and microglial reaction confirmed a neuroprotective effect of the compound. BDNF was effective in increasing significantly the levels of activated CREB and of BDNF the striatal spiny neurons. Moreover, systemically administered BDNF increased the synthesis of BDNF as demonstrated by RT-PCR, and this might account for the beneficial effects observed in this model.
Gómez-Palacio-Schjetnan, Andrea; Escobar, Martha L
Brain-derived neurotrophic factor (BDNF) has been proposed as a key regulator and mediator of long-term synaptic modifications related to learning and memory maintenance. Our previous studies show that application of high-frequency stimulation (HFS) sufficient to elicit LTP at the dentate gyrus (DG)-CA3 pathway produces mossy fiber structural modifications 7 days after tetanic stimulation. In the present study, we show that acute intrahippocampal microinfusion of BDNF induces a lasting potentiation of synaptic efficacy in the DG-CA3 projection of anesthetized adult rats. Furthermore, we show that BDNF functional modifications in synaptic efficacy are accompanied by a presynaptic structural long-lasting reorganization at the hippocampal mossy fiber pathway. These findings support the idea that BDNF plays an important role as synaptic messenger of activity-dependent synaptic plasticity in the adult mammalian brain, in vivo.
Hui YU; Zhe-yu CHEN
Depression is one of the most prevalent and life-threatening forms of mental illnesses and the neural circuitry underlying depression remains incompletely understood. Most attention in the field has focused on hippocampal and frontal cortical regions for their roles in depression and antidepressant action. While these regions no doubt play important roles in the mental illness, there is compelling evi-dence that other brain regions are also involved. Brain-derived neurotrophic factor (BDNF) is broadly expressed in the developing and adult mammalian brain and has been implicated in development, neural regeneration, synaptic transmission, synaptic plasticity and neurogenesis. Recently BDNF has been shown to play an important role in the pathophysiology of depression, however there are con-troversial reports about the effects of BDNF on depression. Here, we present an overview of the current knowledge concerning BDNF actions and associated intracellular signaling in hippocampus, prefrontal cortex, nucleus accumbens (NAc) and amygdala as their rela-tion to depression.
Berzi, Angela; Ayata, C Korcan; Cavalcante, Paola; Falcone, Chiara; Candiago, Elisabetta; Motta, Teresio; Bernasconi, Pia; Hohlfeld, Reinhard; Mantegazza, Renato; Meinl, Edgar; Farina, Cinthia
Here we show that in myasthenic thymus several cell types, including thymic epithelial cells (TEC) and immune cells, were the source and the target of the neurotrophic factor brain-derived growth factor (BDNF). Interestingly, many actively proliferating medullary thymocytes expressed the receptor TrkB in vivo in involuted thymus, while this population was lost in hyperplastic or neoplastic thymuses. Furthermore, in hyperplastic thymuses the robust coordinated expression of BDNF in the germinal centers together with the receptor p75NTR on all proliferating B cells strongly suggests that this factor regulates germinal center reaction. Finally, all TEC dying of apoptosis expressed BDNF receptors, indicating that this neurotrophin is involved in TEC turnover. In thymomas both BDNF production and receptor expression in TEC were strongly hindered. This may represent an attempt of tumour escape from cell death.
Rutherford, L C; Nelson, S B; Turrigiano, G G
Recently, we have identified a novel form of synaptic plasticity that acts to stabilize neocortical firing rates by scaling the quantal amplitude of AMPA-mediated synaptic inputs up or down as a function of neuronal activity. Here, we show that the effects of activity blockade on quantal amplitude are mediated through the neurotrophin brain-derived neurotrophic factor (BDNF). Exogenous BDNF prevented, and a TrkB-IgG fusion protein reproduced, the effects of activity blockade on pyramidal quantal amplitude. BDNF had opposite effects on pyramidal neuron and interneuron quantal amplitudes and modified the ratio of pyramidal neuron to interneuron firing rates. These data demonstrate a novel role for BDNF in the homeostatic regulation of excitatory synaptic strengths and in the maintenance of the balance of cortical excitation and inhibition.
Quirié, Aurore; Hervieu, Marie; Garnier, Philippe; Demougeot, Céline; Mossiat, Claude; Bertrand, Nathalie; Martin, Alain; Marie, Christine; Prigent-Tessier, Anne
Physical exercise constitutes an innovative strategy to treat deficits associated with stroke through the promotion of BDNF-dependent neuroplasticity. However, there is no consensus on the optimal intensity/duration of exercise. In addition, whether previous stroke changes the effect of exercise on the brain is not known. Therefore, the present study compared the effects of a clinically-relevant form of exercise on cerebral BDNF levels and localization in control versus stroke rats. For this ...
Yannick Béjot; Claude Mossiat; Maurice Giroud; Anne Prigent-Tessier; Christine Marie
BACKGROUND: Whereas brain-derived neurotrophic factor (BDNF) levels are measured in the brain in animal models of stroke, neurotrophin levels in stroke patients are measured in plasma or serum samples. The present study was designed to investigate the meaning of circulating BDNF levels in stroke patients. METHODS AND RESULTS: Unilateral ischemic stroke was induced in rats by the injection of various numbers of microspheres into the carotid circulation in order to mimic the different degrees o...
Islam, Andi Asadul
- The neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) is a family of polypeptides that play critical role during neuronal development, appear to mediate protective role on neurorepair in ischemic stroke. Naturally in adult brain neurorepair process consist of: angiogenesis, neurogenesis, and neuronal plasticity, it can also be stimulated by endogenous neurorepair. In this study we observed correlation between NGF and BDNF ischemic stroke patient's onset...
The neurotrophin brain-derived neurotrophic factor (BDNF) is a potent regulator of inhibitory synaptic transmission, although the locus of this effect and the underlying mechanisms are controversial. We explored a potential interaction between BDNF and endogenous cannabinoid (endocannabinoid) signaling because activation of type 1 cannabinoid (CB1) receptors potently regulates γ-aminobutyric acid (GABA) release and both trkB tyrosine kinase receptors and CB1 receptors are highly expressed at ...
Turner, Brian A.; Sparrow, Janet; Cai, Bolin; Monroe, Julie; Mikawa, Takashi; Hempstead, Barbara L.
Neurotrophins, via activation of Trk receptor tyrosine kinases, serve as mitogens, survival factors and regulators of arborization during retinal development. Brain-derived neurotrophic factor (BDNF) and TrkB regulate neuronal arborization and survival in late retinal development. However, TrkB is expressed during early retinal developmet where its functions are unclear. To assess TrkB/BDNF actions in the early chick retina, replication-incompetent retroviruses were utilized to over-express a...
Massey, Kerri A; Zago, Wagner M.; Berg, Darwin K.
In the hippocampus, brain-derived neurotrophic factor (BDNF) regulates a number of synaptic components. Among these are nicotinic acetylcholine receptors containing α7 subunits (α7-nAChRs), which are interesting because of their relative abundance in the hippocampus and their high relative calcium permeability. We show here that BDNF elevates surface and intracellular pools of α7-nAChRs on cultured hippocampal neurons and that glutamatergic activity is both necessary and sufficient for the ef...
Elizabeth E Manning
Full Text Available Brain-derived neurotrophic factor (BDNF has been implicated in the pathophysiology of schizophrenia, yet its role in the development of specific symptoms is unclear. Methamphetamine (METH users have an increased risk of psychosis and schizophrenia, and METH-treated animals have been used extensively as a model to study the positive symptoms of schizophrenia. We investigated whether METH treatment in BDNF heterozygous mutant mice (HET has cumulative effects on sensorimotor gating, including the disruptive effects of psychotropic drugs. BDNF HETs and WT littermates were treated during young-adulthood with METH and, following a two-week break, prepulse inhibition (PPI was examined. At baseline, BDNF HETs showed reduced PPI compared to WT mice irrespective of METH pre-treatment. An acute challenge with amphetamine (AMPH disrupted PPI but male BDNF HETs were more sensitive to this effect, irrespective of METH pre-treatment. In contrast, female mice treated with METH were less sensitive to the disruptive effects of AMPH, and there were no effects of BDNF genotype. Similar changes were not observed in the response to an acute apomorphine or MK-801 challenge. These results show that genetically-induced reduction of BDNF caused changes in a behavioural endophenotype relevant to the positive symptoms of schizophrenia. However, major sex differences were observed in the effects of a psychotropic drug challenge on this behaviour. These findings suggest sex differences in the effects of BDNF depletion and METH treatment on the monoamine signaling pathways that regulate PPI. Given that these same pathways are thought to contribute to the expression of positive symptoms in schizophrenia, this work suggests that there may be significant sex differences in the pathophysiology underlying these symptoms. Elucidating these sex differences may be important for our understanding of the neurobiology of schizophrenia and developing better treatments strategies for the
Gourley, Shannon L.; Howell, Jessica L.; Rios, Maribel; DiLeone, Ralph J.; Taylor, Jane R
Anatomically selective medial prefrontal cortical projections regulate the extinction of stimulus–reinforcement associations, but the mechanisms underlying extinction of an instrumental response for reward are less well-defined and may involve structures that regulate goal-directed action. We show brain-derived neurotrophic factor (bdnf) knock-down in the prelimbic, but not orbitofrontal, cortex accelerates the initial extinction of instrumental responding for food and reduces striatal BDNF p...
Zheng, Fei; Luo, Yongneng; Wang, Hongbing
The induction of the immediate early gene Arc is strongly implicated in synaptic plasticity. Although the role of ERK was demonstrated, the regulation of Arc expression is largely unknown. In this study, we investigated the major signaling pathways underlying brain-derived neurotrophic factor (BDNF)-mediated Arc transcription in cultured cortical neurons. The BDNF-stimulated Arc transcription was solely regulated by the Ras-Raf-MAPK signaling through ERK, but not by phosphoinositide 3-kinase ...
Chen, Jia; Li, Cheng-Ren; Yang, Heng; Liu, Juan; Zhang, Tao; Jiao, Shu-Sheng; Wang, Yan-Jiang; Xu, Zhi-Qiang
Mature brain-derived neurotrophic factor has shown promotive effect on neural cells in rodents, including neural proliferation, differentiation, survival, and synaptic formation. Conversely, the precursor of brain-derived neurotrophic factor (proBDNF) has been emerging as a differing protein against its mature form, for its critical role in aging process and neurodegenerative diseases. In the present study, we investigated the role of proBDNF in neurogenesis in the hippocampal dentate gyrus of aged mice and examined the changes in mice learning and memory functions. The results showed that the newborn cells in the hippocampus revealed a significant decline in proBDNF-treated group compared with bovine serum albumin group, but an elevated level in anti-proBDNF group. During the maturation period, no significant change was observed in the proportions of phenotype of the newborn cells among the three groups. In water maze, proBDNF-treated mice had poorer scores in place navigation test and probe test, compared with those from any other group. Thus, we conclude that proBDNF attenuates neurogenesis in the hippocampus and induces the deficits in learning and memory functions of aged mice.
Full Text Available Introduction: It has shown that listening to Mozart music can potentiate spatial tasks in human; and reduce seizure attacks in epileptic patients. A few studies have reported the effects of prenatal plus postpartum exposure of mice to the Mozart music on brain-drived neurotrophic factor (BDNF in the hippocampus. Here we investigated the effect of postpartum exposure to The Mozart music on BDNF concentration in the hippocampus of rat.Methods: Thirty male one day old newborn Wistar rats divided randomly in two equal experimental and control groups. Experimental group exposed to slow rhythm Mozart music (Mozart Sonata for two pianos KV 448, 6 hour per day; sound pressure levels, between 80 and 100 dB for 60 successive days. The control group was kept in separate room with housing conditions like experimental group except music exposure. After 60 days the rats were euthanized and hippocampuses extracted; then the content of BDNF protein was measured using ELISA sandwich method. Results: Data analysis revealed that rats exposed to Mozart Sonata music had significantly increased BDNF content in the hippocampus as compared to control rats (P±0.01. The concentrations of BDNF were 86.30±2.26 and 94.60 ±6.22 ng/g wet weight in control and music exposure groups respectively.Discussion: Exposure to the Mozart music early in life can increase the BDNF concentration in the hippocampus in rats.
Khabour, Omar F; Alzoubi, Karem H; Alomari, Mahmoud A; Alzubi, Mohammad A
Substantial data suggest that cognitive function can be influenced by many lifestyle activities associated with changes in energy metabolism such as exercise and diet. In the current study, we investigated the combined effects of voluntary exercise (access to running wheels) and dietary restriction (every other day fasting, EODF) on spatial memory formation and on the levels of brain-derived neurotrophic factor (BDNF) in the hippocampus of Wistar male rats. Spatial learning and memory formation was assessed using the radial arm water maze (RAWM) paradigm, while BDNF protein was measured using ELISA test. Voluntary exercise and/or EODF were instituted for 6 weeks. Voluntary exercise alone significantly enhanced short-term, intermediate-term, and long-term memory formation, and increased BDNF protein levels in the hippocampus. EODF enhanced mean running wheel activity by approximately twofold. However, EODF did not modulate the effects of exercise on memory formation and expression of BDNF. In addition, EODF alone had no effect on memory and BDNF protein in the hippocampus. In conclusion, results of this study indicate that exercise enhanced while EODF had neutral effect on both spatial memory formation and hippocampus BDNF levels.
Li, Xiaohong; Chen, Chong; Yang, Xiping; Wang, Jingjing; Zhao, Ming-liang; Sun, Hongtao
How to promote neural repair following traumatic brain injury (TBI) has long been an intractable problem. Although acupuncture has been demonstrated to facilitate the neurological recovery, the underlying mechanism is elusive. Brain-derived neurotrophic factor (BDNF) exerts substantial protective effects for neurological disorders. In this study, we found that the level of BDNF and tropomyosin receptor kinase B (TrkB) was elevated spontaneously after TBI and reached up to the peak at 12 h. Nevertheless, this enhancement is quickly declined to the normal at 48 h. After combined stimulation at the acupoints of Baihui, Renzhong, Hegu, and Zusanli, we found that BDNF and TrkB were still significantly elevated at 168 h. We also observed that the downstream molecular p-Akt and p-Erk1/2 were significantly increased, suggesting that acupuncture could persistently activate the BDNF/TrkB pathway. To further verify that acupuncture improved recovery through activating BDNF/TrkB pathway, K252a (specific inhibitor of TrkB) was treated by injection stereotaxically into lateral ventricle. We observed that K252a could significantly prevent the acupuncture-induced amelioration of motor, sensation, cognition, and synaptic plasticity. These data indicated that acupuncture promoted the recovery of neurological impairment after TBI by activating BDNF/TrkB signaling pathway, providing new molecular mechanism for understanding traditional therapy of acupuncture. PMID:28243312
Javeri, Sita; Rodi, Michael; Tary-Lehmann, Magdalena; Lehmann, Paul V; Addicks, Klaus; Kuerten, Stefanie
The role of brain-derived neurotrophic factor (BDNF) in multiple sclerosis and experimental autoimmune encephalomyelitis (EAE) is still unclear. Here we investigate the clinical course, CNS histopathology and peripheral antigen-specific immunity in MP4-induced EAE of BDNF (-/+) mice. We demonstrate that these mice displayed less severe disease compared to BDNF (+/+) mice, reflected by decreased inflammation and demyelination. In correspondence to diminished frequencies of T and B cells in CNS infiltrates, the peripheral MP4-specific T(H)1/T(H)17 response was attenuated in BDNF (-/+), but not in wild-type animals. In contrast, immunization with ovalbumin triggered similar frequencies of IFN-γ- and IL-17-secreting T cells in both groups. The cytokine secretion and proliferative activity upon mitogen stimulation did not reveal any global defect of T cell function in BDNF (-/+) mice. By influencing the antigen-specific immune response in autoimmune encephalomyelitis, BDNF may support and maintain the disease in ways that go beyond its alleged neuroprotective role.
Yamamoto, Tetsu; Hirayama, Akihiko; Hosoe, Nobuo; Furube, Masaru; Hirano, Shusuke
Our previous study showed that mice fed a soft diet after weaning had reduced synaptic connections in the hippocampal formation and impaired spatial learning ability after 3 months of age. We hypothesized that soft-diet feeding during development reduced levels of brain-derived neurotrophic factor (BDNF) protein in the hippocampus, resulting in lower synaptic densities in this region. Male pups of C57BL/6 mice were fed either a solid (hard-diet group) or powdered diet (soft-diet group), starting at weaning. Expression of BDNF protein in the hippocampus and cerebral cortex was evaluated quantitatively with enzyme-linked immunosorbent assay (ELISA) at 1, 3 and 6 months of age. Reduction in BDNF protein levels due to soft diet was detected markedly in the hippocampus of 3- and 6-month-old mice. On the other hand, a soft diet showed no significant effect on BDNF content in the cerebral cortex throughout the ages investigated. Immunohistochemistry of hippocampal formation in 3-month-old mice revealed that intensities of BDNF immunoreactivity in the dentate gyrus granule cell layer and CA1 and CA3 pyramidal cell layers appeared diminished in mice fed the soft diet compared with mice fed the hard diet. These results indicate that insufficient mastication activity during development reduces BDNF protein levels in the hippocampus and influences synaptic plasticity in this region.
Xu, Xuting; Ji, Huihui; Liu, Guili; Wang, Qinwen; Liu, Huifen; Shen, Wenwen; Li, Longhui; Xie, Xiaohu; Zhou, Wenhua; Duan, Shiwei
As a member of the neurotrophic factor family, brain derived neurotrophic factor (BDNF) plays an important role in the survival and differentiation of neurons. The aim of our work was to evaluate the role of BDNF promoter methylation in drug addiction. A total of 60 drug abusers (30 heroin and 30 methylamphetamine addicts) and 52 healthy age- and gender-matched controls were recruited for the current case control study. Bisulfite pyrosequencing technology was used to determine the methylation levels of five CpGs (CpG1-5) on the BDNF promoter. Among the five CpGs, CpG5 methylation was significantly lower in drug abusers than controls. Moreover, significant associations were found between CpG5 methylation and addictive phenotypes including tension-anxiety, anger-hostility, fatigue-inertia, and depression-dejection. In addition, luciferase assay showed that the DNA fragment of BDNF promoter played a key role in the regulation of gene expression. Our results suggest that BDNF promoter methylation is associated with drug addiction, although further studies are needed to understand the mechanisms by which BDNF promoter methylation contributes to the pathophysiology of drug addiction.
Griffin, Éadaoin W; Mullally, Sinéad; Foley, Carole; Warmington, Stuart A; O'Mara, Shane M; Kelly, Aine M
Physical activity has been reported to improve cognitive function in humans and rodents, possibly via a brain-derived neurotrophic factor (BDNF)-regulated mechanism. In this study of human subjects, we have assessed the effects of acute and chronic exercise on performance of a face-name matching task, which recruits the hippocampus and associated structures of the medial temporal lobe, and the Stroop word-colour task, which does not, and have assessed circulating concentrations of BDNF and IGF-1 in parallel. The results show that a short period of high-intensity cycling results in enhancements in performance of the face-name matching, but not the Stroop, task. These changes in cognitive function were paralleled by increased concentration of BDNF, but not IGF-1, in the serum of exercising subjects. 3 weeks of cycling training had no effect on cardiovascular fitness, as assessed by VO2 scores, cognitive function, or serum BDNF concentration. Increases in fitness, cognitive function and serum BDNF response to acute exercise were observed following 5 weeks of aerobic training. These data indicate that both acute and chronic exercise improve medial temporal lobe function concomitant with increased concentrations of BDNF in the serum, suggesting a possible functional role for this neurotrophic factor in exercise-induced cognitive enhancement in humans.
Full Text Available In the recent years the perirhinal cortex (PRh has been identified as a crucial brain area in fear learning. Since the neurotrophin BDNF (brain-derived neurotrophic factor is an important mediator of synaptic plasticity and also crucially involved in memory consolidation of several learning paradigms, we analyzed now whether fear conditioning influences the expression of BDNF protein in the PRh. Here we observed a specific increase of BDNF protein 120 minutes after fear conditioning training. In order to test whether this increase of BDNF protein level is also required for the consolidation of the fear memory, we locally applied the Trk receptor inhibitor k252a into the PRh during this time window in a second series of experiments. By interfering with BDNF-TrkB-signaling during this critical time window, the formation of a long-term fear memory was completely blocked, indicated by a complete lack of fear potentiated startle one day later. In conclusion the present study further emphasizes the important role of the PRh in cued fear learning and identified BDNF as an important mediator for fear memory consolidation in the PRh.
Tauber, Simone C; Stadelmann, Christine; Spreer, Annette; Brück, Wolfgang; Nau, Roland; Gerber, Joachim
Proliferation and differentiation of neural progenitor cells is increased after bacterial meningitis. To identify endogenous factors involved in neurogenesis, expression of brain-derived neurotrophic factor (BDNF), TrkB, nerve growth factor (NGF), and glial cell line-derived neurotrophic factor (GDNF) was investigated. C57BL/6 mice were infected by intracerebral injection of Streptococcus pneumoniae. Mice were killed 30 hours later or treated with ceftriaxone and killed 4 days after infection. Hippocampal BDNF mRNA levels were increased 2.4-fold 4 days after infection (p = 0.026). Similarly, BDNF protein levels in the hippocampal formation were higher in infected mice than in control animals (p = 0.0003). This was accompanied by an elevated proliferation of dentate granule cells (p = 0.0002). BDNF protein was located predominantly in the hippocampal CA3/4 area and the hilus of the dentate gyrus. The density of dentate granule cells expressing the BDNF receptor TrkB as well as mRNA levels of TrkB in the hippocampal formation were increased 4 days after infection (p = 0.027 and 0.0048, respectively). Conversely, NGF mRNA levels at 30 hours after infection were reduced by approximately 50% (p = 0.004). No significant changes in GDNF expression were observed. In conclusion, increased synthesis of BDNF and TrkB suggests a contribution of this neurotrophic factor to neurogenesis after bacterial meningitis.
Ding, You-Quan; Li, Xuan-Yang; Xia, Guan-Nan; Ren, Hong-Yi; Zhou, Xin-Fu; Su, Bing-Yin; Qi, Jian-Guo
Schwann cell migration, including collective migration and chemotaxis, is essential for the formation of coordinate interactions between Schwann cells and axons during peripheral nerve development and regeneration. Moreover, limited migration of Schwann cells imposed a serious obstacle on Schwann cell-astrocytes intermingling and spinal cord repair after Schwann cell transplantation into injured spinal cords. Recent studies have shown that mature brain-derived neurotrophic factor, a member of the neurotrophin family, inhibits Schwann cell migration. The precursor form of brain-derived neurotrophic factor, proBDNF, was expressed in the developing or degenerating peripheral nerves and the injured spinal cords. Since "the yin and yang of neurotrophin action" has been established as a common sense, proBDNF would be expected to promote Schwann cell migration. However, we found, in the present study, that exogenous proBDNF also inhibited in vitro collective migration and chemotaxis of RSC 96 cells, a spontaneously immortalized rat Schwann cell line. Moreover, proBDNF suppressed adhesion and spreading of those cells. At molecular level, proBDNF inhibits F-actin polymerization and focal adhesion dynamics in cultured RSC 96 cells. Therefore, our results suggested a special case against the classical opinion of "the yin and yang of neurotrophin action" and implied that proBDNF might modulate peripheral nerve development or regeneration and spinal cord repair through perturbing native or transplanted Schwann cell migration.
Frontera, Jimena Laura; Cervino, Ailen Soledad; Jungblut, Lucas David; Paz, Dante Agustín
Olfactory epithelium has the capability to continuously regenerate olfactory receptor neurons throughout life. Adult neurogenesis results from proliferation and differentiation of neural stem cells, and consequently, olfactory neuroepithelium offers an excellent opportunity to study neural regeneration and the factors involved in the maintenance and regeneration of all their cell types. We analyzed the expression of BDNF in the olfactory system under normal physiological conditions as well as during a massive regeneration induced by chemical destruction of the olfactory epithelium in Xenopus laevis larvae. We described the expression and presence of BDNF in the olfactory epithelium and bulb. In normal physiological conditions, sustentacular (glial) cells and a few scattered basal (stem) cells express BDNF in the olfactory epithelium as well as the granular cells in the olfactory bulb. Moreover, during massive regeneration, we demonstrated a drastic increase in basal cells expressing BDNF as well as an increase in BDNF in the olfactory bulb and nerve. Together these results suggest an important role of BDNF in the maintenance and regeneration of the olfactory system.
Eugene V Gasanov
Full Text Available BDNF and its specialized receptor TrkB are expressed in the developing lateral line system of zebrafish, but their role in this organ is unknown. To tackle this problem in vivo, we used transgenic animals expressing fluorescent markers in different cell types of the lateral line and combined a BDNF gain-of-function approach by BDNF mRNA overexpression and by soaking embryos in a solution of BDNF, with a loss-of-function approach by injecting the antisence ntrk2b-morpholino and treating embryos with the specific Trk inhibitor K252a. Subsequent analysis demonstrated that the BDNF-TrkB axis regulates migration of the lateral line primordium. In particular, BDNF-TrkB influences the expression level of components of chemokine signaling including Cxcr4b, and the generation of progenitors of mechanoreceptors, at the level of expression of Atoh1a-Atp2b1a.
Pang, Petti T; Teng, Henry K; Zaitsev, Eugene; Woo, Newton T; Sakata, Kazuko; Zhen, Shushuang; Teng, Kenneth K; Yung, Wing-Ho; Hempstead, Barbara L; Lu, Bai
Long-term memory is thought to be mediated by protein synthesis-dependent, late-phase long-term potentiation (L-LTP). Two secretory proteins, tissue plasminogen activator (tPA) and brain-derived neurotrophic factor (BDNF), have been implicated in this process, but their relationship is unclear. Here we report that tPA, by activating the extracellular protease plasmin, converts the precursor proBDNF to the mature BDNF (mBDNF), and that such conversion is critical for L-LTP expression in mouse hippocampus. Moreover, application of mBDNF is sufficient to rescue L-LTP when protein synthesis is inhibited, which suggests that mBDNF is a key protein synthesis product for L-LTP expression.
Full Text Available We investigated the influences of putative candidate genes for psychosis on premorbid social adjustment and on premorbid schizoid-schizotypal traits. A family-based sample was used including 177 patients with schizophrenia or bipolar I disorder with a history of psychotic symptoms, 86 of their unaffected relatives, and 116 unrelated healthy controls. Association analyses on the combined sample were conducted using the Statistical Analysis for Genetic Epidemiology software (SAGE and adjusting for age, sex, clinical group, and the family-based nature of the data. The COMT Val158Met and BDNF Val66Met polymorphisms showed no evidence of association with either phenotype. The SNP rs221533 of the NRG1 gene was significantly associated with premorbid adjustment in adolescence with TT homozygous subjects having a poorer performance than C allele carriers. In the context of neurodevelopmental disorders such as schizophrenia and other psychoses, this finding is plausible; however, it is preliminary and requires replication in an independent sample. In a broader sense, the use of intermediate quantitative phenotypes such as the ones presented in this study may be of help to understand the mechanism of action of genetic risk factors.
Apostol, Barbara L; Simmons, Danielle A; Zuccato, Chiara; Illes, Katalin; Pallos, Judit; Casale, Malcolm; Conforti, Paola; Ramos, Catarina; Roarke, Margaret; Kathuria, Satish; Cattaneo, Elena; Marsh, J Lawrence; Thompson, Leslie Michels
Huntington's disease (HD) is a devastating neurodegenerative disorder caused by an expanded polyglutamine repeat within the protein Huntingtin (Htt). We previously reported that mutant Htt expression activates the ERK1/2 and JNK pathways [Apostol, B.L., Illes, K., Pallos, J., Bodai, L., Wu, J., Strand, A., Schweitzer, E.S., Olson, J.M., Kazantsev, A., Marsh, J.L., Thompson, L.M., 2006. Mutant huntingtin alters MAPK signaling pathways in PC12 and striatal cells: ERK1/2 protects against mutant huntingtin-associated toxicity. Hum. Mol. Genet. 15, 273-285]. Chemical and genetic modulation of these pathways promotes cell survival and death, respectively. Here we test the ability of two closely related compounds, CEP-11004 and CEP-1347, which inhibit Mixed Lineage Kinases (MLKs) and are neuroprotective, to suppress mutant Htt-mediated pathogenesis in multiple model systems. CEP-11004/CEP-1347 treatment significantly decreased toxicity in mutant Htt-expressing cells that evoke a strong JNK response. However, suppression of cellular dysfunction in cell lines that exhibit only mild Htt-associated toxicity and little JNK activation was associated with activation of ERK1/2. These compounds also reduced neurotoxicity in immortalized striatal neurons from mutant knock-in mice and Drosophila expressing a mutant Htt fragment. Finally, CEP-1347 improved motor performance in R6/2 mice and restored expression of BDNF, a critical neurotrophic factor that is reduced in HD. These studies suggest a novel therapeutic approach for a currently untreatable neurodegenerative disease, HD, via CEP-1347 up-regulation of BDNF.
Jose Luis Nieto-Gonzalez; Kimmo Jensen
In addition to their classical roles in neuronal growth, survival and differentiation, neurotrophins are also rapid regulators of excitability, synaptic transmission and activity-dependent synaptic plasticity. We have recently shown that mature BDNF (Brain Derived Neurotrophic Factor), but not proBDNF, modulates the excitability of interneurons in dentate gyrus within minutes. Here, we used brain slice patch-clamp recordings to study the mechanisms through which BDNF modulates the firing of i...
Trajkovska, V.; Vinberg, M.; Aznar, S.
and protected against affective disorder. Whole blood assessed for BDNF concentrations and correlated to risk status, neuroticism, and number of stressful life events. RESULTS: Between the groups, we found no significant difference in whole blood BDNF levels. Women at high-risk for depression who had...... neuroticism scores and two or less recent stressful events were associated with decreased whole blood BDNF levels (n=50, p