BDNF In Group Research Articles

The regulation of adipokines related to obesity and diabetes is sensitive to BDNF levels and adipose tissue location.

The role of BDNF in adipose tissue metabolism is poorly understood. We investigated the effects of decreased levels of BDNF on the expression of major adipokines in different fat depots (e.g., subcutaneous and epididymal) of mouse groups fed three different diet protocols. BDNF heterozygous (+ / -) mice were used to evaluate the effect of reduced BDNF levels. Six groups of C57BL/6J breed wild type (WT) and BDNF (+ / -) mice were formed. These groups were fed, respectively, a control diet (CD), a high-fat diet (HFD), and a high-sucrose diet (HSD) for 4months. Serum samples and adipose tissues were used for biochemical assays. The serum concentrations and tissue expression levels of leptin, adiponectin, and resistin were measured. Compared to the CD-fed WT group (control group), serum leptin and leptin expression levels were found to be higher in all experimental groups. Serum adiponectin levels were lower in the BDNF (+ / -) groups and HFD-fed WT group than in the control group. Epididymal adiponectin expression was found to be lower in the HFD-fed BDNF (+ / -) group and higher in HSD-fed groups than in the control group. Compared to the control group, adiponectin expression increased in the WT groups in subcutaneous adipose tissue. Serum resistin levels were elevated in the HFD-fed groups. Resistin expression in epididymal adipose tissue was lower in the CD-fed and HFD-fed groups than in the control group. BDNF levels and diet differentially affect the expression of adipokines in different fat tissues in the body. BDNF may play a protective role in obesity and diabetes.

BDNF eksikliği ve endoplazmik retikulum stresinin GABAerjik sistem üzerindeki etkileri

Purpose: Protective pathways against endoplasmic reticulum stress in neurons are activated via brain-derived neurotrophic factor. However, it is not known how the inhibitory intermediate neuron types expressing the different Ca2+-binding proteins of GABAergic system will be affected with changes in Ca2+ homeostasis, in conditions of chronic reduction of brain-derived neurotrophic factor and endoplasmic reticulum stress. The study was planned to reveal the interaction of these factors. Materials and methods: 6-8 months old (30-40 g), wild-type (WT) and brain-derived neurotrophic factor heterozygous (BDNF(+/-)) male mice were used and 4 groups were formed. Groups 3 and 4 were treated with a single dose of tunicamycin to induce endoplasmic reticulum stress. On the 3rd day of tunicamycin injection, animals were sacrificed and blood and brain tissues were taken. In serum samples BDNF, in tissue homogenates GRP78, CHOP, Caspase-12, parvalbumin, calretinin, calbindin, GAD65 and GAD67 levels were investigated by ELISA method. One-way ANOVA and Tukey post-hoc tests were used for statistical evaluation. Results: Serum BDNF levels were significantly lower in BDNF(+/-) and tunicamycin-treated BDNF(+/-) groups. Caspase-12 and CHOP levels significantly increased with tunicamycin injection. Calbindin level decreased significantly with endoplasmic reticulum stress. GAD65 and GAD67 levels were similar in WT and BDNF(+/-) groups. However, GAD65 level was significantly decreased during endoplasmic reticulum stress in WT and BDNF(+/-) groups. Conclusion: Endoplasmic reticulum stress caused a significant decrease in glutamic acid decarboxylase GAD65 isoform and caldindin levels. This result indicates that the sensitivity of varied intermediate neurons in GABAergic system to endoplasmic reticulum stress may be different.

BDNF Augments NMDA‐signaling and Reduces GABAA‐signaling in the Paraventricular Nucleus of the Hypothalamus (PVN) to Elevate Blood Pressure

PVN presympathetic neurons, projecting to the rostral ventrolateral medulla (RVLM) or the spinal cord, play a critical role in the regulation of blood pressure. BDNF is a neurotrophic factor known to be upregulated in the PVN in response to hypertensive stimuli such as stress. However, the mechanisms by which BDNF modulates cardiovascular regulation in the PVN remains unclear. BDNF alters glutamatergic and GABAergic signaling, as well as neuronal morphology broadly in the central nervous system. Within the PVN, glutamatergic synaptic input and NMDA‐signaling are elevated, while GABAergic inhibition is reduced in hypertensive models. We tested the hypothesis that increased BDNF expression in the PVN elevates blood pressure by enhancing NMDA‐signaling, diminishing GABAA‐signaling and altering morphology of RVLM‐projecting PVN neurons. To simulate stress‐related upregulation of BDNF in the PVN, an AAV2 viral vector expressing BDNF was bilaterally injected into the PVN of Sprague Dawley rats, while control rats received AAV2‐GFP injections. Three weeks later, blood pressure and heart rate responses to PVN injections of NMDA and GABAA agonists and antagonists were recorded under anesthesia. Our results showed that inhibition of NMDA receptors with AP5 induced significantly larger decreases in blood pressure and heart rate in the BDNF group (−23±4 mmHg and −56±17 BPM) compared with the GFP group [5±1 mmHg (p<0.01) and −5±1 BPM (p<0.05)]. In contrast, activation of NMDA receptors with NMDA induced similar cardiovascular responses in GFP and BDNF animals. Inhibition of GABAA receptors with gabazine induced significantly smaller blood pressure increases in the BDNF group (32±6 mmHg) compared to GFP (61±11 mmHg, p<0.05), but heart rate responses were similar in the two groups. Activation of GABAA receptors with muscimol caused significantly reduced hypotensive responses in the BDNF group (−14±2 mmHg) compared to GFP (−23±4 mmHg, p<0.05), while changes in heart rate were similar. Quantitative RT‐PCR from PVN brain punches indicated that expression of NMDAR1 or GABAA‐Δ was unaffected by BDNF overexpression. However, immunofluorescence imaging in PVN brain sections demonstrated that BDNF significantly increased the soma size of RVLM‐projecting PVN neurons. In summary, our findings indicate that BDNF augments glutamate signaling in the PVN, primarily by increasing presynaptic glutamate release, and reduces GABA inhibition possibly through postsynaptic mechanisms. Finally, BDNF may also affect the balance of excitatory/inhibitory synaptic balance and regulation of blood pressure by increasing the soma size of PVN‐RVLM neurons.Support or Funding InformationR01 HL133211‐01A1.

The Effect of Intranasal Administration of ACTH Analogue Toward Neural Progenitor/Stem Cells Proliferation after Traumatic Brain Injury

Traumatic brain injury (TBI) is a major health problem because of its high mortality and long-term disability worldwide. Neural progenitor/stem cells (NPSCs) that survive in certain parts of the brain, enable brain to produce new neurons and glia. ACTH4-10Pro8-Gly9-Pro10 has a modulation effect on the expression and activation of the BDNF/TrkB system in the hippocampus area. The BDNF/TrkB pathway system is a potential therapeutic target toward NPSCs proliferation after TBI. Thirty male Sprague-Dawley rats were divided into three groups, i.e A=sham-operated controls; B=TBI; C=TBI+intranasal ACTH4-10Pro8-Gly9-Pro10 administration. After 24 h, rats’ brains were immunohistochemically processed, to observe the number of cells expressing mBDNF, TrkB, and SOX2 in the subgranular zone(SGZ) of the hippocampus dentate gyrus(DG). Data were analyzed with SPSS 17, ANOVA, Post Hoc Tukey HSD test, with p value < 0,05. Mean expression of BDNF group C=16.33 ± 2.83 increased significantly compared to group A=8.33 ± 1.32(p=0.0001) and group B=5.89 ±1.69(p=0.0001). Mean expression of TrkB group C=17.00 ± 1.58 increased significantly compared to group A=4.33 ± 1.73(p=0.0001) and group B=5.89 ± 2.47(p=0.0001), TrkB expression in group B increased insignificantly compared to group A (p= 0.234). Mean expression of SOX2 in group C=12.56 ± 2.07 increased significantly compared to group B = 8.89 ±2.318(p=0.0001) and group A=4.89 ± 2.42(p=0.0001). ACTH4-10Pro8-Gly9-Pro10 can increase the expression of BDNF and TrkB, and the proliferation of NPSCs in the subgranular zone (SGZ) of the hippocampus dentate gyrus (DG).

Articulation recovery in ALS patients after lineage-negative adjuvant cell therapy - preliminary report.

Background: Amyotrophic lateral sclerosis (ALS) is one of the most frequently occurring neurodegenerative diseases affecting speech and swallowing. This preliminary study aimed to investigate whether an autologous lineage-negative stem/progenitor cell therapy applied to ALS patients affects the level of selected trophic and proinflammatory factors, and subsequently improves the articulation.Methods: We enrolled 12 patients with sporadic ALS, who underwent autologous bone marrow-derived lineage negative (LIN-) cells administration into cerebrospinal fluid (CSF). We evaluated patients' articulation using the Frenchay Dysarthria Assessment on days 0 and 28 following the LIN- cells administration. Concentrations of various factors (BDNF, NGF, ANGP-2, VEGF, PDGF-AA, PEDF, COMP-FH, CRP, C3, C4) in CSF were quantified by multiplex fluorescent bead-based immunoassays in the samples collected on the day of LIN- cells administration and 28 days later. On top of this, we assessed levels of BDNF and NGF in the patients' plasma on the day of the injection, three, seven days and three months after the treatment.Results: Of the 12 patients who received the LIN- cell therapy 8 showed short-termed improvement in articulatory functions (group I), which was particularly noticeable in better phonation time, lips and soft palate performance, swallowing reflex and voice loudness. Four patients (group II) did not show substantial improvement. CSF concentrations of BDNF, ANGP-2 and PDGF-AA in group I decreased significantly 28 days after LIN- cells administration. The highest concentration levels of BDNF in group II and NGF in both groups in blood plasma were observed on day 3 following the injection.Conclusions: The outcomes of the LIN- cell application in ALS treatment of articulatory organs are promising. The procedure proved to be safe and feasible. A short-lasting trophic effect of autologous LIN- administration could encourage repeated cell's application in order to sustain their beneficial effects, however this approach needs further investigation.

Effect and mechanism of suberoylanilide hydroxamic acid on fear extinction in mice with chronic social defeat stress

Objective To investigate the effect and mechanism of suberoylanilide hydroxamic acid(SAHA) on the fear extinction in mice with chronic social defeat stress (SD). Methods Fifty-six male C57BL/6J mice aged 7-8 weeks were randomly divided into control group, social defeat group, control-SAHA group and social defeat-SAHA group to investigate the effect of SAHA and social defeat group, social defeat-AAV BDNF group and social defeat-AAV blank group to investigate the effect of BDNF. Fear extinction in mice was evaluated by fear conditioning test (FC). The levels of BDNF and HDAC2 in mice hippocampus were detected by Western blot (WB). The expression of BDNF-overexpressing virus in hippocampus of mice was detected by immunofluorescence assay. Results (1)Compared with control group, fear extinction in the social defeat group was significantly decreased (P<0.05). Compared with control group, the level of HDAC2(0.50±0.02)in the social defeat group was significantly increased (P<0.001), while the level of BDNF(0.16±0.03)was significantly decreased (P<0.001) in the social defeat group. (2)After using SAHA, fear extinction of mice significantly improved (P<0.05). Compared with control group, the level of HDAC2 (0.26±0.02) in the control-SAHA group was significantly decreased(P<0.001), and the level of BDNF (0.40±0.03) was significantly increased (P<0.001). Compared with social defeat group, the level of HDAC2 (0.39±0.03) in the social defeat-SAHA group was significantly decreased (P<0.001), and the level of BDNF (0.28±0.01) was significantly increased (P<0.001). (3)After injection BDNF-overexpressing virus, fear extinction was significantly improved(P<0.05). Conclusion SAHA can enhance fear extinction in mice with chronic social defeat stress and its mechanism may be related to the up-regulation of BDNF expression in hippocampus by inhibiting HDAC2 in hippocampal. Key words: Suberoylanilide hydroxamic acid, histone deacetylases inhibitor; Brain-derived neurotrophic factor; Chronic stress; Fear extinction; Social defeat

BDNF shifts excitatory‐inhibitory balance in the paraventricular nucleus of the hypothalamus (PVN) to elevate blood pressure

The PVN is an important cardiovascular and autonomic center involved in sympathetic nerve activity and blood pressure (BP) regulation. Stimulation of PVN presympathetic neurons elevate sympathetic activity and BP via excitatory glutamatergic projections to the rostral ventrolateral medulla and the intermediolateral cell column of the spinal cord. Presympathetic neuronal activity is regulated by the balance of excitatory glutamatergic and inhibitory GABA‐ and noradrenergic signaling. BDNF is a neurotrophic factor capable of modulating glutamatergic, GABAergic and catecholaminergic (CA‐ergic) signaling in the CNS by changing expression and membrane trafficking of neurotransmitter receptors and transporters and by increasing the soma size of neurons. Within the PVN, BDNF expression is upregulated in response to physical and psychological stressors; therefore, BDNF may play a significant role in mediating stress‐induced changes in autonomic regulation of BP. Thus, we set out to examine the long‐term effects of BDNF overexpression within the PVN on NMDA‐, GABAA‐ and adrenergic receptor‐mediated BP mechanisms and its effect on PVN neuronal soma size. To test this, Sprague Dawley (SD) rats received bilateral PVN injections of AAV2 viral vectors expressing either GFP or BDNF. Three weeks later, BP and heart rate (HR) responses to PVN injections of AP5 (10 mM), an NMDA antagonist, gabazine (2 mM), a GABAA receptor antagonist, and isoprenaline (250 μM), a non‐selective β‐adrenergic agonist, were recorded under alpha chloralosed‐urethane anesthesia. To test if BDNF alters the soma size of PVN neurons, fixed PVN brain sections were analyzed in ImageJ to quantify the soma size of BDNF or GFP expressing neurons. Our results showed that in the BDNF group, peak decreases in BP and HR in response to AP5 were −21±4 mmHg and − 38±13 BPM, compared with −2±1 mmHg (p&lt;0.0001) and −3±1 BPM (p&lt;0.0001) in the GFP group. In response to gabazine, peak increases in BP and HR in the BDNF group were 52±3 mmHg and 85±19 BPM, compared with 91±6 mmHg (p&lt;0.01) and 20±3 BPM (p=0.06, n.s.) in the GFP group. In response to isoprenaline, peak decreases in BP and HR in the BDNF group were −8±1 mmHg and −19±12 BPM, compared with −35±2 mmHg (p&lt;0.001) and −34±9 BPM (p=0.39, n.s.) in the GFP group. Analysis of PVN neuronal dimensions showed that the BDNF treated group had a significantly larger average soma size of 220±11 μm2 compared to the GFP group of 122±6 μm2 (p&lt;0.0001). In summary, our findings indicate BDNF may alter the excitatory‐inhibitory balance in the PVN by enhancing glutamatergic and diminishing GABAergic and CA‐ergic signaling mechanisms within the PVN. In addition, BDNF‐induced increases in the volume and membrane surface area of PVN neurons could also contribute to long‐term changes in BP regulatory mechanisms.Support or Funding InformationSupported by R01 HL133211‐01A1 and UVM start‐up funds.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Effect of a high sucrose and high fat diet in BDNF (+/-) mice on oxidative stress markers in adipose tissues

The purpose of this study was to investigate the effects of a high fat and a high sucrosediet in wild type and BDNF (+/-) mice on oxidative stress in epididymal and subcutaneousadipose tissues by measuring different markers of oxidative stress and antioxidant enzymes. Wild type (WT) and BDNF (+/-) male mice were divided into six groups receiving fed control diet (CD), high sucrose diet (HSD), or high fat diet (HFD) for four months. Levels of 3-nitrotyrosine (3-NT) increased in the HFD-fed BDNF (+/-) mice, while 4-hydroxynonenal (4-HNE) levels increased in the CD and HFD-fed BDNF (+/-) groups. Malondialdehyde (MDA) levels decreased in subcutaneous tissue compared to epididymal adipose tissue, independently of diet type. Superoxide dismutase (SOD) activity was reduced by HFD (p < 0.05), butglutathione peroxidase (GSH-Px) activity was increased by HSD in epididymal adipose tissuein BDNF (+/-) mice (p < 0.05). GSH-Px activities was increased by CD and HFD in subcutaneous adipose tissue of BDNF (+/-) (p < 0.05). SOD2 and GSH-Px3 expressions were only decreased by HSD in epididymal and subcutaneous adipose tissues of BDNF (+/-) mice (p < 0.05). In conclusion, reduced BDNF may increase OS in epididymal adipose tissue, but not in subcutaneous adipose tissue following HSD and HFD.

Combined use of NGF/BDNF/bFGF promotes proliferation and differentiation of neural stem cells in vitro

Neurotrophic factors can promote the proliferation and differentiation of neural stem cells (NSCs). Here we report that the possibility of using bFGF in combination with BDNF and NGF to promote proliferation and differentiation of NSCs in vitro. C57BL/6 mouse NSCs were cultured, passaged and stained by immunofluorescence for nestin and GFP. According to different neurotrophic factors added to NSCs, seven experiment groups (NGF, BDNF, bFGF, bFGF+NGF, bFGF+BDNF, NGF+BDNF and NGF+BDNF+bFGF) and a blank control group were established. One week after induction and differentiation, results showed that there was significant difference in the percentage of NSCs differentiating into neurons among the experiment groups. The percentage in the multi-factor groups was significantly higher than that in the single-factor groups (p<0.05), among which the percentage was the highest in NGF+BDNF+bFGF group. In the two-factor groups, the percentage in bFGF+NGF and bFGF+BDNF groups was significantly higher than that in NGF+BDNF group (p<0.05). The NSCs growth curves showed that cells proliferated continuously with the time of culture prolonging, but there was significant difference between the group containing bFGF and that without bFGF. Our results demonstrate that combined use of NGF/BDNF/bFGF significantly improved the ability of NSCs proliferation and differentiation.

Brain‐derived neurotrophic factor overexpression in the paraventricular nucleus increases blood pressure via angiotensin type‐1 receptor‐mediated mechanisms (686.3)

BDNF expression increases in the PVN during hypertensive stimuli including stress and hyperosmolarity, and we have shown previously that overexpression of BDNF in the PVN leads to significant increases in mean arterial blood pressure (MAP). Here, we tested the hypothesis that BDNF‐induced pressor responses are mediated by angiotensin signaling in the central nervous system. MAP was recorded in male Sprague‐Dawley rats using telemetry. At 11wks of age, adeno‐associated viral vectors (AAV2‐GFP or AAV2‐BDNF) were injected bilaterally into the PVN, and losartan (Los; 15µg/ 0.5µL/ hour) or saline was infused icv for 4 wks using osmotic pumps. During the 4 wks after vector injections, MAP remained unchanged in the GFP+saline (dMAP=2.5±0.4 mmHg) and GFP+Los (dMAP=2.6±1.2 mmHg) groups. MAP increased markedly in both BDNF groups, but the increase was significantly reduced in BDNF+Los (dMAP=15.0±3.2 mmHg) compared with BDNF+saline (dMAP=28.7±2.2 mmHg, p&lt;0.05). RT‐PCR from PVN tissue samples of AAV2‐GFP and AAV2‐BDNF‐injected rats indicated that BDNF significantly upregulated AT1R mRNA (2‐ddCt was 1.1±0.2 in GFP and 2.0±0.4 in BDNF rats using 18s as internal control, p&lt;0.05). In contrast, mRNA levels of angiotensinogen, angiotensin converting enzyme (ACE), ACE2 and AT2R were unaffected by BDNF. We conclude that the BDNF‐induced MAP increase is partially mediated by AT1R, which is upregulated by BDNF within the PVN.Grant Funding Source: Supported by AHA 11SDG7560022, an AFAR research grant, and by NIH #HL76807, #HL93186.

Effects of tyrosine kinase receptor B-brain-derived neurotrophic factor signal pathway on the secretion of vascular endothelial growth factor and matrix metalloproteinase-9 of neuroblastoma

Objective To study the effects of tyrosine kinase receptor B-brain-derived neurotrophic factor (TrkB-BDNF) signal pathway on the secretion of vascular endothelial growth factor (VEGF) and matrix metalloproteinases-9(MMP-9) of neuroblastoma.Methods We used all-trans retinoic acid (ATRA) to induce the high expression of TrkB in the SH-SY5Y cell line,and then added the ectogenid BDNF to activate the TrkB-BDNF and its three downstream signal pathways.TrkB-BDNF signal pathway was inhibited by specific tyrosine kinase inhibitor K252a.The three downstream signal pathway was respectively inhibited by LY294002 (the phosphatidylinositol 3-hydroxy kinase (PI3 K) pathway inhibitor)、U73122 (the phospholipase C pathway inhibitor) 、U0126(the mitogen activated protein kinase pathway inhibitor).Enzyme linked immunosorbent assay was used to detect the concentration of VEGF and MMP-9 protein in the SY5Y cell culture supernatants.Results VEGF [(485.89 ± 109.99) pg/ml] and MMP-9 [(15.73 ± 1.72) pg/ml] protein levels in neuroblastoma cells cultured in serum-free media in the group of ATRA + BDNF were significantly higher than that of the control group and ATRA alone group(P ＜0.05).VEGF [(272.42 ±86.33) pg/ml]and MMP-9 [(5.25 ± 1.44) pg/ml] protein levels in the group of ATRA + BDNF + K252a were significantly lower than those of the ATRA + BDNF group(P ＜ 0.05) and had no significant difference compared with the control group and the ATRA alone group(P ＞0.05).VEGF [(314.12 ±24.68) pg/ml] and MMP-9 [(4.91 ± 1.08) pg/ml] protein levels in the group of ATRA + BDNF + LY294002 were significantly lower than those of the ATRA + BDNF group(P ＜ 0.05) and had no significant difference compared with the control group and the ATRA alone group(P ＞0.05).VEGF [(444.08 ±64.49) pg/ml] and MMP-9 [(13.28 ±3.38) pg/ml] protein levels in neuroblastoma cells cultured in serum-free media in the group of ATRA +BDNF + U73122 had no significant difference compared with the ATRA + BDNF group(P ＞ 0.05).VEGF [(429.97 ± 19.95) pg/ml] and MMP-9 [(13.96 ± 4.45) pg/ml] protein levels in neuroblastoma cells cultured in serum-free media in the group of ATRA + BDNF + U0126 had no significant difference compared with the ATRA + BDNF group(P ＞ 0.05).Conclusion Activation of TrkB-BDNF signal pathway can increase the synthesis and secretion of VEGF and MMP-9 in human neuroblastoma cells.TrkB-BDNF signal pathway may be through activating its downstream PI3K pathway to increase the synthesis and secretion of VEGF and MMP-9 in human neuroblastoma cells.The synthesis and secretion of VEGF and MMP-9 can be inhibited by blocking the TrkB-BDNF signal pathway with K252a or blocking its downstream signal pathway PI3 K with LY294002. Key words: Neuroblastoma; TrkB-BDNF signal pathway; K252a; LY294002; Vascular endothelial growth factor; Matrix metalloproteinases-9

Cografted Wharton’s Jelly Cells-derived Neurospheres and BDNF Promote Functional Recovery After Rat Spinal Cord Transection

An animal model of transected spinal cord injury (SCI) was used to test the hypothesis that cografted human umbilical mesenchymal stem cells-derived neurospheres (HUMSC-NSs) and BDNF can promote morphologic and functional recoveries of injured spinal cord. In vitro, HUMSC-NSs terminally differentiated into higher percentages of cells expressing neuronal markers: beta-tubulin III and MAP2ab by the supplement with BDNF. Following grafted into injured spinal cord, very few grafted cells survived in the HUMSC-NSs + BDNF-treated (<3%) and HUMSC-NSs-treated (<1%) groups. The survived cells were differentiated into various cells, which were confirmed by double staining of BrdU and neural or glia markers. In comparison, more grafted cells in the HUMSC-NSs + BDNF group transformed into mature neural-like cells, while more grafted cells in the HUMSC-NSs group transformed into oligodendrocyte-like cells. HUMSC-NSs + BDNF-treated group had more greatly improved BBB scores, compared with HUMSC-NSs-treated and medium-treated groups. Additionally, axonal regeneration showed significant improvement in rats receiving HUMSC-NSs + BDNF, compared with HUMSC-NSs-treated and medium-treated groups, as demonstrated by the NF-200-positive staining and Fluorogold (FG) retrograde tracing study. Lastly, a significant reduction in the percentage cavitation was seen in the two cell-treated groups compared with medium control group. These results means BDNF could promote the neural differentiation of HUMSC-NSs in vitro and in vivo. However, cellular replacement is unlikely to explain the improvement in functional outcome. The functional recovery might more rely on the axonal regeneration and neuroprotective action that active by the grafted cells. Cografted HUMSCs and BDNF is a potential therapy for SCI.

Regeneration of spinal cord with cell and gene therapy

Transplantation of fetal spinal cord cells (FSCC) can promote regeneration of injured spinal cord, while Schwann cells (SC) and some growth factors have a similar effect. However, the synergistic effects and optimal combination of these modalities have not yet been evaluated. In the current study, the efficiency of cell therapy of FSCC and/or SC, with/without growth factors (nerve growth factor [NGF] and brain-derived neurotrophic factor [BDNF]) was examined, with the aim of establishing an optimized protocol for spinal cord injury. One hundred and twenty adult rats were randomly divided into six groups with 20 rats in each group. One week after the thoracic spinal cord injury model had been created, the rats were treated with different therapeutic modalities: Dulbecco's modified Eagles medium (DMEM) in Group I, FSCC in Group II, FSCC plus SC in Group III, FSCC plus SC over-expressing NGF in Group IV, FSCC plus SC over-expressing BDNF in Group V, and FSCC plus SC over-expressing both NGF and BDNF in Group VI. Subsequently, the rats were subjected to behavioral tests once a week after injury, while histology, immunohistochemistry and electron microscopy were performed at one and three month post-operation. Both SC and FSCC promoted regeneration of spinal cord injury when used separately, while a combination of the two types of cell resulted in better recovery than either alone. Both growth factors (NGF and BDNF) enhanced the outcomes of cell therapy, while synergistic effects meant that a combination of each individual component (group VI) achieved the best results according to locomotion scale, histology and immunoreactivity in the injured cords. SC, NGF and BDNF can enhance the outcome of FSCC therapy, while the combination of FSC with SC, NGF and BDNF is possibly the optimal protocol for clinical treatment of acute spinal cord injury.

Gelatin–tricalcium phosphate membranes immobilized with NGF, BDNF, or IGF‐1 for peripheral nerve repair: An in vitro and in vivo study

In the present study, NGF, BNDF from the neurotrophin family and IGF-1 were covalently immobilized on gelatin-tricalcium phosphate (GTG) membrane using carbodiimide. We investigated the effects of these growth factors released from the GTG composites on cultured PC12 cells and sciatic nerve regeneration across a 10-mm-long gap in rats. In PC12 cell culture, the total protein content and MTT assay indicated more cell attachment on the composites modified with growth factors. The IGF-1 group showed a higher survival promotion effect on PC12 cells than did BDNF and NGF groups. On the other hand, NGF released from the composite showed the highest level of neuritogenesis for PC12 cells in neurite outgrowth assay. In the animal study, the GTG conduits modified with various growth factors were well tolerated by the host tissue. In the regenerated nerves, the number of the axons per unit area of the BDNF group was significantly higher than that of NGF and GTG groups but similar to that of IGF-1 group. However, the average axon size was the largest in NGF group. This result was in concordance with the neurite outgrowth assay in which NGF showed the highest neuritogenic potential. In the assessment of motor and sensory recovery after nerve repair, conduits modified with various neurotrophic factors showed a more favorable outcome in compound muscle action potential. The BDNF group had a better gastrocnemic muscle weight ratio than blank GTG repair. Nevertheless, the different effects of GTG conduits modified with various neurotrophic factors on functional recovery cannot be simply illustrated in the sciatic function index.

Methionine-free brain-derived neurotrophic factor in wobbler mouse motor neuron disease: dose-related effects and comparison with the methionyl form

We compared the clinical and pharmacodynamic effects of N-terminal methionine brain-derived neurotrophic factor (met-BDNF) and endogenous met-free BDNF in wobbler mouse motor neuron disease (MND). Met- or met-free BDNF at 5 or 20 mg/kg was subcutaneously injected daily, six times/week for 4 weeks. At 20 mg/kg, grip strength ( P<0.05, met-free BDNF; P<0.01, met-BDNF) and running speed ( P<0.01 for both groups) improved compared to vehicle. At 5 mg/kg, the beneficial effect was more modest. Plasma BDNF levels after the final injection were dose-dependent and did not differ between BDNF groups. Endogenous met-free BDNF exerts effects similar to met-BDNF in wobbler MND.

BDNF atelocollagen mini-pellet accelerates facial nerve regeneration

We investigated the effect of BDNF mini-pellet on the GAP-43 mRNA expression and functional status of facial nerve in a rat model of facial nerve transection and immediate repair. The facial function started to recover at 17 days in the placebo group and 14 days in the BDNF group. BDNF group had shorter period of increased GAP-43 mRNA expression than the placebo group. Topically applied BDNF may accelerate the facial nerve regeneration.

Rat fetal ventral mesencephalon grown as solid tissue cultures: influence of culture time and BDNF treatment on dopamine neuron survival and function

Free-floating roller tube (FFRT) cultures of fetal rat and human nigral tissue are a means for tissue storage prior to grafting in experimental Parkinson's disease. In the present study, FFRT cultures prepared from embryonic-day-14 rat ventral mesencephalon were maintained for 4, 8, 12, or 16 days in vitro (DIV) in the presence or absence (controls) of BDNF [100 ng/ml]. The dopamine content in the culture medium, analyzed by HPLC, was significantly higher (4–5 fold) in the BDNF group at DIV 8 and DIV 12 compared to the corresponding control levels (40 pg/ml). The number of tyrosine hydroxylase immunoreactive neurons was significantly higher for BDNF treated cultures (2729±300) at DIV 8, as compared to controls (1679±217). At DIV 12, the culture volume was significantly increased by BDNF (1.05±0.12 vs. 0.71±0.04 mm 3). Similar results were obtained for total protein. Western blot analysis demonstrated increasing signals for GFAP with increasing time in culture, but levels for control and BDNF treated cultures did not differ at any time-point investigated. In conclusion, it is suggested that the time window for effective storage of dopaminergic tissue prior to grafting can be extended by using the FFRT culture technique and that the in vitro storage may be further prolonged by treatment with BDNF.