OBJECTIVETo investigate the growth and development of brain derived neurophic factor(BDNF)-positive neurons in the frontal lobe of human fetus.

METHODSThe expression of the BDNF-positive neurons in the frontal lobe of human fetus in the 2(nd),3(rd),and 4(th) month of gestation were observed with the streptavidin-biotin-complex/immunoperoxidase(SABC)method.

RESULTSBy the second month of gestation,BDNF-positive neurons were seen in the subventricular layer of the frontal lobe of cerebellum.By the third month of gestation,BDNF-positive neurons in the central layer were in various shapes,with big nucleus,less cytoplasm,and small processes.By the fourth month of gestation,BDNF-positive neurons in the central layer grew larger in size,cytoplasm increased,the BDNF-positive expression was enhanced with deeper dyeing,and the nerve fibers and particles were distributed between neurons;also,the BDNF-positive neurons were seen in the marginal layer of the frontal lobe of cerebrum.

CONCLUSIONBDNF-positive neurons may participate in the early development of the frontal lobe of cerebrum of human fetus.

Brain-Derived Neurotrophic Factor ; metabolism ; Fetus ; metabolism ; Frontal Lobe ; embryology ; Humans ; Neurons ; cytology ; metabolism

This commentary highlights the recently published study by Jeon and Ha (Environ Health Prev Med 22:27, 2017) examining the effects of exercise intensity and brain-derived neurotrophic factor (BDNF) on memory in adolescents. This 12-week training study elicited increases in BDNF and improvements in working memory during moderate- and high-intensity exercise, which may have been achieved through improved brain tissue oxygenation, nutrient delivery, and BDNF mRNA expression. These improvements highlight the positive neuroendocrinological effects of BDNF and its role as a potential candidate molecule, as a mediator of synaptic plasticity. In this commentary, we aim to highlight the strengths and potential areas of consideration of Jeon and Ha (Environ Health Prev Med 22:27, 2017). We also offer insight into the clinical implications of this study, such as advocating for exercise in healthy children and as adjunctive therapy in pathological states. This study is promising and further highlights the importance of cardiorespiratory exercise in improving physiological health and cognitive functioning in youth through the phenomenon of neuroplasticity.
Adolescent ; Brain-Derived Neurotrophic Factor ; metabolism ; Exercise ; physiology ; Humans ; Memory ; physiology

Danzhi Xiaoyao Powder is a classical prescription for anxiety. This study aims to analyze the effect of this medicine on mitochondrial morphology and function of anxiety rats and explore the mechanism of it against anxiety. Specifically, uncertain empty bottle drinking water stimulation(21 days) was employed to induce anxiety in rats. The elevated plus-maze test and open field test were respectively performed on the 7 th, the 14 th, and the 21 st days of the stimulation, so as to detect the anxiety-related protein index brain-derived neurotrophic factor(BDNF) and evaluate the anxiety level of animals. On this basis, the effect of this prescription on anxiety rats was preliminarily evaluated. After the behavioral test on the 21 st day, rats were killed and the brain tissues were separated for the observation of the mitochondrial morphology and the determination of mitochondrial function-related indicators and the adenosine 5'-monophosphate-activated protein kinase(AMPK) level. The results showed that Danzhi Xiaoxiao Powder could alleviate the anxiety-like behavior of rats, significantly increase the percentage of time in open arm in elevated plus-maze test and the ration of activity time in the central area of the field, dose-dependently raise the activity levels of respiratory chain complex Ⅰ,Ⅱ,Ⅲ and Ⅳ and the adenosine triphosphate(ATP) content, and elevate the levels of BDNF and phosphorylated AMPK(p-AMPK). Clear structure and intact morphology of mitochondrial cristae in medial prefrontal cortex cells and amygdala were observed in the Danzhi Xiaoyao Powder group. In summary, Danzhi Xiaoyao Powder exerts therapeutic effect on anxiety, and the mechanism is the likelihood that p-AMPK protects the structure and maintains the function of mitochondria.
Rats ; Animals ; Brain-Derived Neurotrophic Factor/metabolism* ; Powders ; AMP-Activated Protein Kinases ; Anxiety/drug therapy* ; Mitochondria

Brachial plexus avulsion (BPA) is a combined injury involving the central and peripheral nervous systems. Patients with BPA often experience severe neuropathic pain (NP) in the affected limb. NP is insensitive to the existing treatments, which makes it a challenge to researchers and clinicians. Accumulated evidence shows that a BPA-induced pain state is often accompanied by sympathetic nervous dysfunction, which suggests that the excitation state of the sympathetic nervous system is correlated with the existence of NP. However, the mechanism of how somatosensory neural crosstalk with the sympathetic nerve at the peripheral level remains unclear. In this study, through using a novel BPA C7 root avulsion mouse model, we found that the expression of BDNF and its receptor TrκB in the DRGs of the BPA mice increased, and the markers of sympathetic nervous system activity including α1 and α2 adrenergic receptors (α1-AR and α2-AR) also increased after BPA. The phenomenon of superexcitation of the sympathetic nervous system, including hypothermia and edema of the affected extremity, was also observed in BPA mice by using CatWalk gait analysis, an infrared thermometer, and an edema evaluation. Genetic knockdown of BDNF in DRGs not only reversed the mechanical allodynia but also alleviated the hypothermia and edema of the affected extremity in BPA mice. Further, intraperitoneal injection of adrenergic receptor inhibitors decreased neuronal excitability in patch clamp recording and reversed the mechanical allodynia of BPA mice. In another branch experiment, we also found the elevated expression of BDNF, TrκB, TH, α1-AR, and α2-AR in DRG tissues from BPA patients compared with normal human DRGs through western blot and immunohistochemistry. Our results revealed that peripheral BDNF is a key molecule in the regulation of somatosensory-sympathetic coupling in BPA-induced NP. This study also opens a novel analgesic target (BDNF) in the treatment of this pain with fewer complications, which has great potential for clinical transformation.
Humans ; Mice ; Animals ; Hyperalgesia/metabolism* ; Brain-Derived Neurotrophic Factor/metabolism* ; Hypothermia/metabolism* ; Neuralgia ; Brachial Plexus/injuries* ; Edema/metabolism*

Chronic stress is generally accepted as the main risk factor in the development of cognitive decline; however, the underlying mechanisms remain unclear. Previous data have demonstrated that the levels of homocysteine (Hcy) are significantly elevated in the plasma of stressed animals, which suggests that Hcy is associated with stress and cognitive decline. To test this hypothesis, we analyzed the cognitive function, plasma concentrations of Hcy, and brain-derived neurotropic factor (BDNF) levels in rats undergoing chronic unpredicted mild stress (CUMS). The results showed that decreased cognitive behavioral performance and decreased BDNF transcription and protein expression were correlated with hyperhomocysteinemia (HHcy) levels in stressed rats. Diet-induced HHcy mimicked the cognitive decline and BDNF downregulation in the same manner as CUMS, while Hcy reduction (by means of vitamin B complex supplements) alleviated the cognitive deficits and BDNF reduction in CUMS rats. Furthermore, we also found that both stress and HHcy disturbed the DNA methylation process in the brain and induced DNA hypermethylation in the BDNF promoter. In contrast, control of Hcy blocked BDNF promoter methylation and upregulated BDNF levels in the brain. These results imply the possibility of a causal role of Hcy in stress-induced cognitive decline. We also used ten-eleven translocation (TET1), an enzyme that induces DNA demethylation, to verify the involvement of Hcy and DNA methylation in the regulation of BDNF expression and the development of stress-related cognitive decline. The data showed that TET1-expressing viral injection into the hippocampus inhibited BDNF promoter methylation and significantly mitigated the cognitive decline in HHcy rats. Taken together, novel evidence from the present study suggests that Hcy is likely involved in chronic stress-induced BDNF reduction and related cognitive deficits. In addition, the negative side-effects of HHcy may be associated with Hcy-induced DNA hypermethylation in the BDNF promoter. The results also suggest the possibility of Hcy as a target for therapy and the potential value of vitamin B intake in preventing stress-induced cognitive decline.
Animals ; Brain-Derived Neurotrophic Factor/metabolism* ; Cognitive Dysfunction/complications* ; DNA Methylation ; Homocysteine/metabolism* ; Hyperhomocysteinemia/metabolism* ; Rats ; Stress, Psychological/physiopathology*

OBJECTIVE: To investigate whether meranzin hydrate (MH) can alleviate depression-like behavior and hypomotility similar to Chaihu Shugan Powder (CSP), and further explore the potential common mechanisms. METHODS: Totally 120 Spraque-Dawley rats were randomly divided into 5-8 groups including sham, vehicle, fluoxetine (20 mg/kg), mosapride (10 mg/kg), CSP (30 g/kg), MH (9.18 mg/kg), [D-Lys3]-GHRP-6 (Dlys, 0.5 mg/kg), and MH+Dlys groups by a random number table, 8 rats in each group. And 32 mice were randomly divided into wild-type, MH (18 mg/kg), growth hormone secretagogue receptor-knockout (GHSR-KO), and GHSR+MH groups, 8 mice in each group. The forced swimming test (FST), open field test (OFT), tail suspension test (TST), gastric emptying (GE) test, and intestinal transit (IT) test were used to assess antidepressant and prokinetic (AP) effects after drug single administration for 30 min with absorbable identification in rats and mice, respectively. The protein expression levels of brain-derived neurotrophic factor (BDNF) and phosphorylated mammalian target of rapamycin (p-mTOR) in the hippocampus of rats were evaluated by Western blot. The differences in functional brain changes were determined via 7.0 T functional magnetic resonance imaging-blood oxygen level-dependent (fMRI-BOLD). RESULTS: MH treatment improved depression-like behavior (FST, OFT) and hypomotility (GE, IT) in the acute forced swimming (FS) rats (all P<0.05), and the effects are similar to the parent formula CSP. The ghrelin antagonist [D-Lys3]-GHRP-6 inhibited the effect of MH on FST and GE (P<0.05). Similarly, MH treatment also alleviated depression-like behavior (FST, TST) in the wild-type mice, however, no effects were found in the GHSR KO mice. Additionally, administration of MH significantly stimulated BDNF and p-mTOR protein expressions in the hippocampus (both P<0.01), which were also prevented by [D-Lys3]-GHRP-6 (P<0.01). Besides, 3 main BOLD foci following acute FS rats implicated activity in hippocampus-thalamus-basal ganglia (HTB) circuits. The [D-Lys3]-GHRP-6 synchronously inhibited BOLD HTB foci. As expected, prokinetic mosapride only had effects on the thalamus and basal ganglia, but not on the hippocampus. Within the HTB, the hippocampus is implicated in depression and FD. CONCLUSIONS MH accounts for part of AP effects of parent formula CSP in acute FS rats, mainly via ghrelin-related shared regulation coupled to BOLD signals in brain areas. This novel functionally connection of HTB following acute stress, treatment, and regulation highlights anti-depression unified theory.
Rats ; Mice ; Animals ; Brain-Derived Neurotrophic Factor/metabolism* ; Ghrelin/metabolism* ; Antidepressive Agents/therapeutic use* ; Hippocampus ; Stress, Psychological ; Mammals/metabolism*

Suicide is a complex phenomenon resulting from interactions between individual vulnerabilities and socio-environmental factors. The current review primarily focuses on research into the serotonin system, hypothalamic-pituitary-adrenal axis, neurotrophic factors, lipid metabolism, and functional neuroimaging studies. It has been found that dysfunctions in the serotonin system, hypothalamic-pituitary-adrenal axis abnormalities, and low brain-derived neurotrophic factor and cholesterol levels may be linked to suicide. Additionally, recent neuroimaging studies have suggested that structural and functional abnormalities in brain areas related to cognitive and emotional regulation may be associated with suicide. More research incorporating advanced methodological approaches may shed further light on the neurobiological basis of suicide.
Brain ; Brain-Derived Neurotrophic Factor ; Cholesterol ; Functional Neuroimaging ; Lipid Metabolism ; Nerve Growth Factors ; Neurobiology ; Neuroimaging ; Pituitary-Adrenal System ; Serotonin ; Suicide

OBJECTIVE: To investigate the inhibitory effect of ANA-12 that blocks brain-derived neurotrophic factor (BDNF)/ tropomyosin receptor kinase B (TrkB) signaling on inflammatory pain in rats and explore the underlying mechanism. METHODS: Forty-two adult SD rats were randomized into BDNF-induced acute pain group (n=24) and CFA-induced chronic pain group. The former group were randomly divided into 4 subgroups, including a control group, ANA-12 treatment group, BDNF treatment group, and BDNF+ANA-12 treatment group; the latter group were subgrouped into control group, CFA treatment group (CFA) and CFA + ANA-12 treatment group. The effects of ANA-12 treatment on pain behaviors of the rats with BDNF-induced acute pain and CFA-induced chronic inflammatory pain were observed. Western blotting was used to examine TrkB signaling and expressions of microglia marker protein Iba1 and TNF-α in the spinal cord of the rats. RESULTS: BDNF injection into the subarachnoid space significantly increased the number of spontaneous paw withdrawal of the rats (P < 0.05), which was obviously reduced by ANA-12 treatment (P < 0.05). The rats with intraplantar injection of CFA, showed significantly increased ipsilateral mechanical stimulation sensitivity (P < 0.05), and ANA-12 treatment obviously increased the ipsilateral foot withdrawal threshold (P < 0.05). Treatment with either BDNF or CFA significantly increased the phosphorylation level of TrkB (Y705) in the spinal cord of the rats (P < 0.05), which was significantly lowered by ANA-12 treatment (P < 0.05). Treatment with BDNF and CFA both significantly up-regulated the expressions of Iba1 and TNF-α in the spinal cord (P < 0.05), but ANA-12 significantly reduced their expression levels (P < 0.05). CONCLUSION ANA-12 can reduce spinal cord inflammation and relieve acute and chronic pain in rats by targeted blocking of BDNF/TrkB signaling.
Animals ; Brain-Derived Neurotrophic Factor/metabolism* ; Chronic Pain/drug therapy* ; Inflammation ; Rats ; Rats, Sprague-Dawley ; Receptor, trkB/metabolism*

Animals ; Brain-Derived Neurotrophic Factor ; metabolism ; Hypothalamus ; metabolism ; Male ; Physical Conditioning, Animal ; physiology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo observe the effects of electroacupuncture (EA) combined with Compound Salviae Miltiorrhizae Tablet (CSMT) on the expressions of brain derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) in hippocampus CA1 of chronic cerebral ischemia (CCI) rats.

METHODSTotally 50 Sprague-Dawley rats were randomly divided into the normal control group, the model group, the CSMT group, the EA group, and the EA +CSMT groups, 10 in each group. The CCI model was prepared by permanent bilateral common carotid arteries occlusion. One week after modeling, CSMT at 0.75 g/kg was given to rats in the EA + CSMT group and the CSMT group by gastrogavage, once daily, for 5 successive weeks. EA at Baihui (DU20) and Dazhui (DU14) was performed to rats in the EA group and the EA + CSMT group, lasting for 30 min, once daily, for 5 successive weeks. The expressions of BDNF and VEGF in the hippocampus CA1 area were detected by immunohistochemical assay and image analysis.

RESULTSCompared with the normal control group, the number of positively expressed BDNF and VEGF neurons and their expression intensity in the hippocampus CA1 of the model group obviously decreased (P < 0.01). Compared with the model group, the number of positively expressed BDNF and VEGF neurons and their expression intensity in the hippocampus CA1 of the CSMT group, the EA group, and the EA + CSMT groups obviously increased (P < 0.01, P < 0.05). The number of positively expressed BDNF and VEGF neurons and their expression intensity were obviously higher in the EA + CSMT group than those of the CSMT group and the EA group (P < 0.01).

CONCLUSIONSEA combined with CSMT could significantly increase the expressions of BDNF and VEGF in the hippocampus CA1 of CCl rats. Besides, their effects were significantly higher than those of the CSMT group or the EA group.

Animals ; Brain Ischemia ; metabolism ; therapy ; Brain-Derived Neurotrophic Factor ; metabolism ; CA1 Region, Hippocampal ; metabolism ; Electroacupuncture ; Male ; Rats ; Rats, Sprague-Dawley ; Salvia miltiorrhiza ; Vascular Endothelial Growth Factor A ; metabolism