Brain-derived Neurotrophic Factor Antisense Research Articles

E2F1 Mediates Traumatic Brain Injury and Regulates BDNF-AS to Promote the Progression of Alzheimer's Disease.

Traumatic brain injury (TBI) is one of the important risk factors for the development of Alzheimer's disease (AD). However, the molecular mechanism by which TBI promotes the progression of AD is not elucidated. In this study, we showed that the abnormal production of E2F1 is a major factor in promoting the neuropathological and cognitive deterioration of AD post-TBI. We found that repeated mild TBI can aggravate the neuropathology of AD in APP/PS1 mice. At the same time, the co-expression of E2F1 and beta-site APP cleaving enzyme 1 (BACE1) was upregulated when the mouse hippocampus was dissected. BACE1 is recognized as a rate-limiting enzyme for the production of Aβ. Here, we speculate that E2F1 may play a role in promoting BACE1 expression in AD. Therefore, we collected peripheral blood from patients with AD. Interestingly, there is a positive correlation between E2F1 and brain-derived neurotrophic factor-antisense (BDNF-AS), whereas BDNF-AS in AD can promote the expression of BACE1 and exhibit a neurotoxic effect. We established a cell model and found a regulatory relationship between E2F1 and BDNF-AS. Therefore, based on our results, we concluded that E2F1 regulates BDNF-AS, promotes the expression of BACE1, and affects the progression of AD. Furthermore, E2F1 mediates the TBI-induced neurotoxicity of AD.

The long non-coding RNA BDNF-AS induces neuronal cell apoptosis by targeting miR-125b-5p in Alzheimer's disease models.

At least 55 million individuals suffer from dementia globally, of which Alzheimer's disease (AD) accounts for 60-70% of cases. Alzheimer's disease is the only major cause of death that is still growing. However, the molecular mechanisms are largely unknown in the progress of AD. The goal of the study was to assess whether lncRNA brain-derived neurotrophic factor antisense (BDNF-AS) could affect processes underlying the regulation of neuronal cell apoptosis in rat and cellular models of AD by directing the expression of miR-125b-5p. The amyloid-β (Aβ)1-42-induced rat and cellular models of AD were established. Changes in learning and memory in rats were detected with the use of the Morris water maze. Cell viability and apoptosis were determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) test and flow cytometry. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was applied to detect the expression of lncRNA BDNF-AS and miR-125b-5p, and western blotting was utilized to examine proteins. The correlations between lncRNA BDNF-AS and miR-125b-5p were demonstrated using dual-luciferase reporter gene assays. Our results showed that BDNF-AS was upregulated and miR-125b-5p was downregulated in the rat and cellular AD models. The addition of si-BDNF-AS and miR-125b-5p mimics shortened the escape latency and swimming distance in the rat model. Furthermore, the knockdown of BDNF-AS or the administration of miR-125b-5p mimic significantly suppressed cell apoptosis, cell inflammatory, and inflammatory pathway-related proteins, while these cellular activities were promoted in rat and cellular models of AD. Additionally, miR-125b-5p was found to be a BDNF-AS target gene that was linked negatively with BDNF-AS in AD. Through regulation of miR-125b-5p, lncRNA BDNF-AS suppressed cell death, inflammation and inflammatory pathway-related proteins in AD models, which provides a potential biomarker and therapeutic target in the clinical treatment of AD.

Association between chronic tinnitus and brain-derived neurotrophic factor antisense RNA polymorphisms linked to the Val66Met polymorphism in BDNF

Tinnitus is the sound heard in the ear or head of a person in the absence of external stimuli. Its etiopathogenesis is still not fully understood and the etiological causes responsible for tinnitus are quite variable. Brain-derived neurotrophic factor (BDNF) is one of the key neurotrophic factors in the growth, differentiation, and survival of neurons and in the developing auditory pathway, including the inner ear sensory epithelium. The regulation of BDNF gene is known to be managed by BDNF antisense (BDNF-AS) gene. BDNF-AS is located downstream of the BDNF gene and transcribes a long non-coding RNA. Inhibition of BDNF-AS upregulates BDNF mRNA, which increases protein levels and stimulates neuronal development and differentiation. Thus, BDNF and BDNF-AS both may play roles in the auditory pathway. Polymorphisms in both genes may have impact on hearing performance. A link was suggested between tinnitus and BDNF Val66Met polymorphism. However, there is no study questioning the relationship of tinnitus with BDNF-AS polymorphisms linked with BDNF Val66Met polymorphism. Therefore, this study aimed to scrutinize the role of BDNF-AS polymorphisms showing linkage with the BDNF Val66Met polymorphism in the course of tinnitus pathophysiology. Six BDNF-AS polymorphisms were analyzed on the tinnitus patients (n = 85) and the control subjects (n = 60) by Fluidigm Real-Time PCR using the Fluidigm Biomark microfluidic platform. When BDNF-AS polymorphisms were compared between the groups in terms of genotype and gender distribution, statistically significant differences were detected in rs925946, rs1519480, and rs10767658, polymorphisms (p less than 0.05). When the polymorphisms were compared by the duration of tinnitus, significant differences were found in rs925946, rs1488830, rs1519480, and rs10767658 polymorphisms (p less than 0.05). According to genetic inheritance model analysis, 2.33 and 1.53-fold risks were found for the rs10767658 polymorphism in the recessive and the additive models, respectively. For the rs1519480 polymorphism, a 2.25 fold risk was observed in the additive model. For the rs925946 polymorphism, 2.44 fold protective effect in dominant model, and 0.62 fold risk was found in the additive model. In conclusion, four of the polymorphisms in BDNF-AS gene (rs955946, rs1488830, rs1519480, and rs10767658) are potential gene loci that may play a role in the auditory pathway and affect auditory performance.

Lithium alleviated spinal cord injury (SCI)-induced apoptosis and inflammation in rats via BDNF-AS/miR-9-5p axis.

Spinal cord injury (SCI) is a major cause of paralysis, disability and even death in severe cases. Lithium has neuroprotective effects on SCI, while the underlying mechanisms remain obscure. In the present study, we established a SCI rat model, which subsequently received lithium treatment. Results displayed that lithium treatment improved the locomotor function recovery and reduced apoptosis by increasing anti-apoptotic molecule expression and decreasing pro-apoptotic factor expression in SCI rats. Furthermore, lithium treatment alleviated the inflammatory response by inactivating the nuclear factor-kappa B (NF-κB) pathway and inhibited the expression of lncRNA brain-derived neurotrophic factor antisense (BDNF-AS) in SCI rats. Subsequent researches indicated that miR-9-5p was targeted and regulated by BDNF-AS. Lithium treatment rescued the upregulation of BDNF-AS expression and downregulation of miR-9-5p expression induced by H2O2 in SH-SY5Y cells. BDNF-AS overexpression or miR-9-5p interference attenuated the anti-apoptotic and anti-inflammatory effects of lithium chloride in SH-SY5Y cells that was damaged by H2O2 induction, revealing that lithium might act through the BDNF-AS/miR-9-5p axis. In vivo studies showed that the injection of BDNF-AS adenovirus vector or miR-9-5p inhibitor reversed the effects of lithium on the histologic morphology of spinal cord, motor function, inflammatory reaction and apoptosis in SCI rats, which was consistent with the results of in vitro studies. In conclusion, our data demonstrated that lithium reduced SCI-induced apoptosis and inflammation in rats via the BDNF-AS/miR-9-5p axis.

LncRNA BDNF-AS promotes autophagy and apoptosis in MPTP-induced Parkinson’s disease via ablating microRNA-125b-5p

BackgroundsRecently, extensive evidence has indicated that the biological role of long non-coding RNAs (lncRNAs) in neurodegenerative diseases is becoming increasingly evident. The lncRNA brain-derived neurotrophic factor anti-sense (BDNF-AS) has been found to be dysregulated in Huntington’s Disease. However, the function of BDNF-AS in Parkinson's disease (PD) remains unknown. The purpose of this present study was to explore the effect of BDNF-AS on PD and its underlying molecular mechanisms. MethodsThe MPTP-induced mouse model of PD and MPP+-induced SH-SY5Y cell model were established. Immunofluorescence was performed to determine the number of TH + positive cells. Mice behavioral changes were detected by pole and rota-rod test. SH-SY5Y cells viability, apoptosis was detected by MTT assay and flow cytometry. The number of autophagosome was measured by transmission electron microscopy. Dopamine content was tested by high performance liquid chromatography. Dual-luciferase reporter gene assay was utilized to verify the correlation between BDNF-AS and miR-125b-5p. qRT-PCR and western blot were used to detect gene expression levels. ResultsOur results showed that BDNF-AS was up-regulated in MPTP-induced PD model and dopamine neurons, and MPP + treated SH-SY5Y cells, while miR-125b-5p was down-regulated. The expression of BDNF-AS was positively related with the MPP + concentration. BDNF-AS knockdown could significantly promote cell proliferation, while inhibit apoptosis and autophagy in SH-SY5Y cells treated by MPP + . Silencing BDNF-AS could also increase TH positive neurons and significantly suppress the autophagy of PD mice. Additionally, miR-125b-5p, a putative target gene of BDNF-AS, was involved in the effects of BDNF-AS on SH-SY5Y cell apoptosis and autophagy. ConclusionsOur study demonstrated that knockdown of BDNF-AS could elevate SH-SY5Y cell viability, inhibit autophagy and apoptosis in MPTP-induced PD models through regulating miR-125b-5p, suggesting that BDNF-AS might act as a potential therapeutic target for PD.

PABPC1-induced stabilization of BDNF-AS inhibits malignant progression of glioblastoma cells through STAU1-mediated decay

Glioblastoma is the most common and malignant form of primary central nervous tumor in adults. Long noncoding RNAs (lncRNAs) have been reported to play a pivotal role in modulating gene expression and regulating human tumor’s malignant behaviors. In this study, we confirmed that lncRNA brain-derived neurotrophic factor antisense (BDNF-AS) was downregulated in glioblastoma tissues and cells, interacted and stabilized by polyadenylate-binding protein cytoplasmic 1 (PABPC1). Overexpression of BDNF-AS inhibited the proliferation, migration, and invasion, as well as induced the apoptosis of glioblastoma cells. In the in vivo study, PABPC1 overexpression combined with BDNF-AS overexpression produced the smallest tumor and the longest survival. Moreover, BDNF-AS could elicit retina and anterior neural fold homeobox 2 (RAX2) mRNA decay through STAU1-mediated decay (SMD), and thereby regulated the malignant behaviors glioblastoma cells. Knockdown of RAX2 produced tumor-suppressive function in glioblastoma cells and increased the expression of discs large homolog 5 (DLG5), leading to the activation of the Hippo pathway. In general, this study elucidated that the PABPC1-BDNF-AS-RAX2-DLG5 mechanism may contribute to the anticancer potential of glioma cells and may provide potential therapeutic targets for human glioma.

LncRNA BDNF-AS suppresses colorectal cancer cell proliferation and migration by epigenetically repressing GSK-3β expression.

This study was designed to investigate the molecular mechanism and biological roles of long non-coding RNA (lncRNA) brain-derived neurotrophic factor antisense (BDNF-AS) in colorectal cancer (CRC). The quantitative real-time PCR (qRT-PCR) and western blotting were performed to detect the expressions of lncRNA BDNF-AS and glycogen synthase kinase-3β (GSK-3β) in human CRC tissues and cell lines. The cell proliferation, transwell migration, and invasion assays were carried out to evaluate the effect of lncRNA BDNF-AS on the growth of CRC cells. RNA pull-down and RNA immunoprecipitation (RIP) assays were conducted to confirm the interaction between lncRNA BDNF-AS and enhancer of Zeste Homologue 2 (EZH2). Chromatin immunoprecipitation (ChIP) assay was used to verify the enrichment of EZH2 and histone H3 lysine 27 trimethylation (H3K27me3) in the promoter region of GSK-3β in CRC cells. LncRNA BDNF-AS expression was significantly decreased, while GSK-3β was highly expressed in human CRC tissues and cell lines. Moreover, lncRNA BDNF-AS induced inhibition of proliferation, migration, and invasion of CRC cells via inhibiting GSK-3β expression. Mechanistically, BDNF-AS led to GSK-3β promoter silencing in CRC cells through recruitment of EZH2. In conclusion, lncRNA BDNF-AS functioned as an oncogene in CRC and shed new light on lncRNA-directed therapeutics in CRC. SIGNIFICANCE OF THE STUDY: LncRNA BDNF-AS is recently reported to be remarkably downregulated in a variety of tumours and served as a tumour suppressor. However, the functions and underlying mechanism of lncRNA BDNF-AS in CRC pathogenesis have not been reported yet. Our study is the first to demonstrate the effect of lncRNA BDNF-AS in CRC and revealed that lncRNA BDNF-AS expression is negatively correlated with the aggressive biological behaviour of CRC. Further investigation demonstrated that lncRNA BDNF-AS functioned as a tumour suppressor in CRC progression by suppressing GSK-3β expression through binding to EZH2 and H3K27me3 with the GSK-3β promoter, shedding light on the diagnosis and therapy for CRC.

The lncRNA BDNF-AS is an epigenetic regulator in the human amygdala in early onset alcohol use disorders

Adolescent alcohol drinking is known to contribute to the development and severity of alcohol use disorders (AUDs) later in adulthood. Recent studies have shown that long non-coding RNAs (lncRNAs) are critical for brain development and synaptic plasticity. One such lncRNA is natural occurring brain-derived neurotrophic factor antisense (BDNF-AS) that has been shown to regulate BDNF expression. The role of BDNF-AS lncRNA in the molecular mechanisms of AUD is unknown. Here, we evaluated the expression and functional role of BDNF-AS in postmortem amygdala of either early onset or late onset alcoholics (individuals who began drinking before or after 21 years of age, respectively) and age-matched control subjects. BDNF-AS expression is increased in early onset but not in late onset AUD amygdala and appears to be regulated epitranscriptomically via decreased N6-methyladenosine on BDNF-AS. Upregulation of BDNF-AS is associated with a significant decrease in BDNF expression and increased recruitment of EZH2, which deposits repressive H3K27 trimethylation (H3K27me3) at regulatory regions in the BDNF gene in the early onset AUD group. Drinking during adolescence also contributed to significant decreases in activity-regulated cytoskeleton-associated protein (ARC) expression which also appeared to be mediated by increased EZH2 deposition of repressive H3K27me3 at the ARC synaptic activity response element. These results suggest an important role for BDNF-AS in the regulation of synaptic plasticity via epigenetic reprogramming in the amygdala of AUD subjects who began drinking during adolescence.

LncRNA BDNF-AS is associated with the malignant status and regulates cell proliferation and apoptosis in osteosarcoma.

Long non-coding RNA (LncRNA) brain-derived neurotrophic factor antisense (BDNF-AS) has been found to be down-regulated and function in a tumor suppressive role in human cancers. However, the expression status and function of BDNF-AS is still unknown in osteosarcoma (OS). In our study, BDNF-AS expression was found to be decreased in OS tissues and cells. Moreover, BDNF-AS low expression was correlated with advanced Enneking stage, large tumor size and poor prognosis in OS patients. The multivariate analysis suggested low expression of BDNF-AS was an independent unfavorable prognostic factor for overall survival in OS patients. The in vitro studies indicated that BDNF-AS overexpression inhibits OS cell proliferation and promotes cell apoptosis through regulating cleaved caspase-3. In conclusion, BDNF-AS serves as a tumor suppressive lncRNA in OS.

Knockdown of lncRNA BDNF-AS suppresses neuronal cell apoptosis via downregulating miR-130b-5p target gene PRDM5 in acute spinal cord injury

ABSTRACTObjective: The present study was designed to investigate the molecular mechanism and biological roles of lncRNA brain-derived neurotrophic factor antisense (lncRNA BDNF-AS) in acute spinal cord injury (ASCI). Methods: The rat model of ASCI and hypoxic cellular model were established to detect the expression of BDNF-AS, miR-130b-5p, PR (PRDI-BF1 and RIZ) domain protein 5 (PRDM5) and cleaved caspase 3 (c-caspase 3) using qRT-PCR and western blot. Basso, Beattie and Bresnahan (BBB) score was carried out to assess neurological function. Flow cytometry was used to determine the apoptosis of neuronal cells. The association among BDNF-AS, miR-130b-5p and PRDM5 were disclosed by RNA immunoprecipitation (RIP) assay, RNA pull-down assay and dual-luciferase reporter assay. Results: BDNF-AS, PRDM5 and c-caspase 3 expression were significantly upregulated, while miR-130b-5p was suppressed in the ASCI group and neuronal cells following hypoxia treatment. BDNF-AS knockdown inhibited neuronal cell apoptosis. Further studies indicated that BDNF-AS functioned as a competing endogenous RNA (ceRNA) by sponging miR-130b-5p in neuronal cells. Further investigations demonstrated that PRDM5 was a target of miR-130b-5p and BDNF-AS knockdown exerted anti-apoptotic effects via miR-130b-5p/PRDM5 axis. Conclusion: The lncRNA BDNF-AS/miR-130b-5p/PRDM5 axis might be a promising therapeutic target for ASCI.

Silencing of LncRNA BDNF-AS attenuates Aβ25-35-induced neurotoxicity in PC12 cells by suppressing cell apoptosis and oxidative stress

ABSTRACTObjective: To explore the effects of long non-coding RNA (lncRNA) brain-derived neurotrophic factor anti-sense (BDNF-AS) on the Aβ25-35-induced neurotoxicity in PC12 cells.Methods: PC12 cells were induced by Aβ25-35 to construct cell injury models of Alzheimer’s disease (AD), and then transfected with siRNA-BDNF-AS. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to detect the expressions of BDNF-AS and BDNF. Besides, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Hoechst33342 staining were utilized to analyze the cell viability and apoptosis, respectively, Western blotting to evaluate the protein expressions, immunofluorescence to assess the Cytochrome C (Cyt C) release, and Rhodamine 123 (Rh123) to measure the mitochondrial membrane potential (MMP).The evaluation of oxidative stress was conducted via the determination of the levels of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT).Results: Aβ25-35 apparently increased BDNF-AS but decreased BDNF in PC12 cells, which also reduced viability and induced apoptosis of PC12 cells. Silencing of BDNF-AS could significantly up-regulate BDNF in Aβ25-35-induced PC12 cells, with the elevated cell viability. Moreover, silencing BDNF-AS inhibited the apoptosis of Aβ25-35-induced PC12 cells, suppressed the release of Cyt C, reduced the expression of cleaved caspase-3 and Bax, and lowered the mean fluorescence intensity (MFI) of Rh123, but it elevated the expression of Bcl-2. Besides, silencing BDNF-AS also reduced ROS intensity and MDA content, but enhanced the activities of SOD and CAT.Conclusion: Silencing BDNF-AS exerts protective functions to increase the viability, inhibit the apoptosis and oxidative stress of Aβ25-35-induced PC12 cells by negative regulation of BDNF.Abbreviations: Aβ25–35: amyloid beta peptide 25–35; AD: Alzheimer’s disease; LncRNA BDNF–AS: long non–coding RNA brain–derived neurotrophic factor anti-sense; OS: Oxidative stress.

Long noncoding RNA BDNF-AS inversely regulated BDNF and modulated high-glucose induced apoptosis in human retinal pigment epithelial cells.

In this study, we characterized the functional role of long noncoding RNA (lncRNA), brain derived neurotrophic factor anti-sense (BDNF-AS) in regulating D-glucose-induced (DGI) apoptosis in human retinal pigment epithelial (RPE) cells. Human RPE cell line, ARPE-19 cells were cultured in vitro and treated with various concentrations of D-glucose for 24 h. A TUNEL assay was applied with immunohistochemical and quantitative approaches to assess the apoptotic effect of D-glucose. Under the condition of 50 mM D-glucose, qPCR was used to assess gene expression of BDNF and BDNF-AS in ARPE-19 cells. Using siRNA transfection, BDNF-AS was endogenously knocked down in ARPE-19 cells. The effects of BDNF-AS downregulation on DGI apoptosis and BDNF expression were assessed by TUNEL assay, qPCR, and Western blot, respectively. Furthermore, in BDNF-AS-downregulated ARPE-19 cells, secondary siRNA transfection was conducted to knock down endogenous BDNF expression. Its effect on BDNF-AS-associated apoptotic regulation was further evaluated. High concentrations of D-glucose induced significant apoptosis in ARPE-19 cells in vitro. With treatment of 50 mM D-glucose, BDNF was markedly downregulated whereas BDNF-AS upregulated in ARPE-19 cells. SiRNA-mediated BDNF-AS downregulation ameliorated DGI apoptosis and upregulated BDNF in ARPE-19 cells. In addition, inhibiting BDNF reversed the protective effect of BDNF-AS downregulation on DGI apoptosis. Our results suggest that BDNF-AS, through inverse regulation of BDNF, might play a critical role in the process of DGI apoptosis in diabetic retinopathy.

Long noncoding nature brain-derived neurotrophic factor antisense is associated with poor prognosis and functional regulation in non-small cell lung caner.

In this study, we evaluated the prognostic potential and functional regulation of human nature antisense, brain-derived neurotrophic factor antisense, in non-small cell lung cancer. Non-small cell lung cancer carcinoma and adjacent non-carcinoma lung tissues were extracted from 151 patients. Their endogenous brain-derived neurotrophic factor antisense expression levels were compared by quantitative reverse transcription polymerase chain reaction. Clinical relevance between endogenous brain-derived neurotrophic factor antisense expression level and patients' clinicopathological variances or overall survival was analyzed. The potential of brain-derived neurotrophic factor antisense being an independent prognostic factor in non-small cell lung cancer was also evaluated. In in vitro non-small cell lung cancer cell lines, brain-derived neurotrophic factor antisense was upregulated through forced overexpression. The effects of brain-derived neurotrophic factor antisense upregulation on non-small cell lung cancer in vitro survival, proliferation, and migration were evaluated by viability, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, and transwell assays. Brain-derived neurotrophic factor antisense is lowly expressed in non-small cell lung cancer carcinoma tissues and further downregulated in late-stage carcinomas. Brain-derived neurotrophic factor antisense downregulation was closely associated with non-small cell lung cancer patients' advanced tumor, lymph node, metastasis stage, and positive status of lymph node metastasis, and confirmed to be an independent prognostic factor for patients' poor overall survival. In non-small cell lung cancer A549 and H226 cell lines, forced overexpression of brain-derived neurotrophic factor antisense did not alter cancer cell viability but had significantly tumor suppressive effect in inhibiting in vitro non-small cell lung cancer proliferation and migration. Endogenous brain-derived neurotrophic factor antisense in non-small cell lung cancer carcinoma could be a potential biomarker for predicting patients' prognosis. Overexpressing brain-derived neurotrophic factor antisense may also have a therapeutic potential in inhibiting non-small cell lung cancer tumor growth.

Long noncoding RNA BDNF-AS is a potential biomarker and regulates cancer development in human retinoblastoma

BackgroundLong non-coding RNAs (lncRNA) have been shown to play important roles in human cancer. We examined expression, prognostic potential and functional roles of lncRNA, brain-derived neurotrophic factor antisense (BDNF-AS) in human retinoblastoma (RB). MethodsBDNF-AS expression in RB tumors was characterized according to the clinicopathological parameters of patients. BDNF-AS mRNA level was compared between RB tumors and normal retinas, as well as RB cell lines and normal retinal epithelial cells. RB patients' overall survival was compared between those with low and high BDNF-AS tumor expressions. Statistical analysis was performed to examine the independence of BDNF-AS being cancer biomarker in RB. In Y79 and WERI-Rb-1 cells, BDNF-AS was upregulated. It's effect on cancer proliferation, migration and cell-cycle transition were assessed. ResultsBDNF-AS is downregulated in RB tumors and cell lines. Low BDNF-AS expression in RB tumors is correlated with patients' advanced clinical stage and tumor differentiation status. Low BDNF-AS expression is associated with shorter overall survival and may be acting as an independent marker in RB. In Y79 and WERI-Rb-1 cells, forced overexpression of BDNF-AS inhibited cancer proliferation and migration. It also induced cell-cycle arrest at G0/G1 phase by downregulating CDC42, Cyclin E and BDNF. ConclusionBDNF-AS is lowly expressed, and may be used as a prognostic biomarker in RB. Upregulating BDNF-AS has inhibitory effect on RB development, probably through the suppression of cell-cycle transition.

Long noncoding RNA BDNF-AS regulates ketamine-induced neurotoxicity in neural stem cell derived neurons.

Ketamine is an anesthetic commonly used in both humans and animals. Emerging evidence has demonstrated that ketamine may induce neurotoxicity in neural stem cell-derived neurons. In this work, we investigated whether long noncoding RNA (lncRNA) Brain derived neurotrophic factor antisense (BDNF-AS) was involved in ketamine-induced neurotoxicity in differentiation of mouse embryonic neural stem cells. Mouse embryonic neural stem cells were differentiated in vitro, and treated with ketamine. The corresponding change in gene expression levels of BDNF and BDNF-AS were assessed by qRT-PCR. BDNF-AS was subsequently downregulated by siRNA. And its effect on protecting neuronal apoptosis, promoting neurite regrowth, and activating TrkB signaling pathways were assessed by TUNEL assay, neurite outgrowth assay, and western blot assay, respectively. In ketamine-injured mouse embryonic neural stem cell-derived neurons, BDNF was downregulated, whereas BDNF-AS was upregulated in dose-dependent manner. SiRNA-mediated BDNF-AS downregulation ameliorated neuronal apoptosis, induced neurite outgrowth, and phosphorylated TrkB signaling pathway after ketamine-induce neurotoxicity in mouse embryonic neural stem cell-derived neurons. Inhibition of BDNF-AS is a novel method to protect ketamine-induced neurotoxicity in mouse embryonic neural stem cell-derived neurons, very likely through the activation of TrkB signaling pathway.

Screening for Small-Molecule Modulators of Long Noncoding RNA-Protein Interactions Using AlphaScreen

Long non–protein coding RNAs (lncRNAs) are an important class of molecules that help orchestrate key cellular events. Although their functional roles in cells are not well understood, thousands of lncRNAs and a number of possible mechanisms by which they act have been reported. LncRNAs can exert their regulatory function in cells by interacting with epigenetic enzymes. In this study, we developed a tool to study lncRNA-protein interactions for high-throughput screening of small-molecule modulators using AlphaScreen technology. We tested the interaction of two lncRNAs: brain-derived neurotrophic factor antisense (BDNF-AS) and Hox transcript antisense RNA (HOTAIR), with Enhancer of zeste homolog 2 (EZH2), a histone methyltransferase against a phytochemical library, to look for small-molecule inhibitors that can alter the expression of downstream target genes. We identified ellipticine, a compound that up-regulates BDNF transcription. Our study shows the feasibility of using high-throughput screening to identify modulators of lncRNA-protein interactions and paves the road for targeting lncRNAs that are dysregulated in human disorders using small-molecule therapies.

Central and Medial Amygdaloid Brain-Derived Neurotrophic Factor Signaling Plays a Critical Role in Alcohol-Drinking and Anxiety-Like Behaviors

Brain-derived neurotrophic factor (BDNF) is a member of the nerve growth factor family of neurotrophins and plays a vital role in synaptic plasticity. This study investigated the involvement of the amygdaloid BDNF system in molecular mechanisms underlying anxiety and alcohol-drinking behaviors. Male Sprague Dawley rats were cannulated targeting central amygdala (CeA), medial amygdala (MeA), or basolateral amygdala (BLA), and BDNF expression was manipulated using an antisense oligodeoxynucleotide (ODN) strategy. Anxiety-like and alcohol-drinking behaviors were measured after infusion of BDNF sense and antisense ODNs with or without BDNF coinfusion, using the elevated plus-maze test and two-bottle free-choice paradigm, respectively. Here we report that BDNF antisense ODN infusions into the CeA and MeA, but not BLA, provoked anxiety-like behaviors in rats, which were rescued by BDNF coinfusion. The levels of BDNF, p-ERK1/2 (phosphorylated extracellular signal-regulated kinases 1/2), and p-CREB (phosphorylated cAMP responsive-element binding protein) were decreased by BDNF antisense, but not by sense, ODN infusions, which were restored to normal after BDNF coinfusions. Furthermore, BDNF antisense ODN infusions into the CeA or MeA, but not into BLA, increased alcohol intake, which was attenuated by BDNF coinfusions. These novel results suggest that decreased BDNF levels in the CeA and MeA, but not in the BLA, are crucial in regulating alcohol-drinking and anxiety-like behaviors in rats.

Brain-derived neurotrophic factor delays hippocampal kindling in the rat

Epileptic seizures increase the expression of brain-derived neurotrophic factor in the hippocampus. Since this neurotrophin exerts modulatory effects on neuronal excitability in this structure, it may play an important role in hippocampal epileptogenesis. This question was addressed by studying the effects of chronic infusions of recombinant brain-derived neurotrophic factor and brain-derived neurotrophic factor antisense in the hippocampus during the first seven days of hippocampal kindling. Infusion with brain-derived neurotrophic factor (6–24 μg/day) significantly delayed the progression of standard hippocampal kindling and strongly suppressed seizures induced by rapid hippocampal kindling. These suppressive effects were dose dependent, long lasting, not secondary to neuronal toxicity and specific to this neurotrophin, as nerve growth factor accelerated hippocampal kindling progression. They also appeared to be specific to the hippocampus, as infusion of brain-derived neurotrophic factor (48 μg/day) in the amygdala only resulted in a slight and transient delay of amygdala kindling. Conversely to the protective effects of exogenous brain-derived neurotrophic factor, chronic hippocampal infusion of antisense oligodeoxynucleotides (12 nmol/day), resulting in reduced expression of endogenous brain-derived neurotrophic factor in the hippocampus, aggravated seizures during hippocampal kindling. Taken together, our results lead us to suggest that the seizure-induced increase in brain-derived neurotrophic factor expression in the hippocampus may constitute an endogenous regulatory mechanism able to restrain hippocampal epileptogenesis.