多发性硬化、视神经脊髓炎患者血清及脑脊液中脑源性神经营养因子与胶质细胞源性神经营养因子水平

目的 探讨多发性硬化(MS)、视神经脊髓炎(NMO)患者血清及脑脊液中脑源性神经营养因子(BDNF)、胶质细胞源性神经营养因子(GDNF)水平及其神经保护作用.方法 对62例MS、NMO患者及21例对照者进行研究,患者组复发期进行扩展残疾状态量表(EDSS)评分、MRI检查及寡克隆带测定,液相芯片分析技术检测血清及脑脊液BDNF、GDNF浓度.结果 MS、NMO患者复发期血清及脑脊液BDNF(μg/L,MS患者:5.616±0.650、0.186±0.012;NMO患者6.584±0.929、0.176±0.006)、GDNF浓度(μg/L,MS患者:0.039、0.080;NMO患者0.029、0.050)与对照组(μg/L,血清:4.374±0.501、0.040;脑脊液:0.152±0.011、0.065)比较差异无统计学意义;脑脊液BDNF与GDNF浓度水平呈正相关(r=0.756,P=0.000),血清BDNF与GDNF浓度水平呈负相关(r=-0.329,P=0.018).血清及脑脊液BDNF、GDNF浓度与EDSS评分、血脑屏障指数、Delpech指数及Tourtellotte合成率无明显相关性.有或无脑萎缩的MS、NMO患者血清及腩脊液BDNF、GDNF浓度差异无统计学意义.结论 MS、NMO患者体内BDNF与GDNF水平相关,二者可能具有协同的神经保护作用.BDNF及GDNF与NMO、MS患者血脑屏障破坏及中枢神经系统内IgG合成无关,与神经功能残疾及脑萎缩的关系仍需研究.     

男性慢性精神分裂症患者血清脑源性神经营养因子和胶质源性神经营养因子水平及认知功能的对照研究

目的:探讨慢性精神分裂症患者血清脑源性神经营养因子(BDNF)、胶质源性神经营养因子水平(GDNF)和神经认知功能的变化及它们之间关系。方法:入组慢性精神分裂症患者57例和正常对照39名。采用阳性与阴性症状量表(PANSS)评估患者的精神症状。使用酶联免疫吸附法检测血清BDNF、GDNF蛋白水平,采用数字划消测验、连线测验(TMT)、WMS-III空间广度测验(WMS-III SST)、定步调连续加法任务测验(PASAT)、Stroop测验、木块图评估神经认知功能。结果:患者组血清BDNF水平低于对照组,差异有统计学意义(t=9.112,P0.01),患者组血清GDNF与对照组相比差异无统计学意义(t=1.513,P0.05)。患者组数字划消测验、TMT-A、TMT-B、Stroop测验、木块图、WMS-III SST逆行分、PASAT成绩均差于对照组(P0.05)。患者组血清BDNF水平与PANSS阳性症状分、数字划消测验中的错误个数呈负相关(分别为r=-0.295,P=0.026;r=-0.262,P=0.049),血清GDNF水平与Stroop色词干扰测验分呈正相关(r=0.263,P=0.048)。结论:慢性稳定期的精神分裂症患者仍存在广泛的神经认知损害。BDNF可能是精神分裂症的一种素质性标记,可能参与了患者的注意障碍。     

Adenoviral gene transfer of GDNF,BDNF and TGF beta 2, but not CNTF,cardiotrophin-1 or IGF1, protects injured adult motoneurons after facial nerve avulsion

We examined neuroprotective effects of recombinant adenoviral vectors encoding glial cell line-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), cardiotrophin-1 (CT1), insulin-like growth factor-1 (IGF1), and transforming growth factor-beta2 (TGFbeta2) on lesioned adult rat facial motoneurons. The right facial nerves of adult Fischer 344 male rats were avulsed and removed from the stylomastoid foramen, and adenoviral vectors were injected into the facial canal. Animals avulsed and treated with adenovirus encoding GDNF, BDNF, CNTF, CT1, IGF1 and TGFbeta2 showed intense immunolabeling for these factors in lesioned facial motoneurons, respectively, indicating adenoviral induction of the neurotrophic factors in these neurons. The treatment with adenovirus encoding GDNF, BDNF, or TGFbeta2 after avulsion significantly prevented the loss of lesioned facial motoneurons, improved choline acetyltransferase immunoreactivity and prevented the induction of nitric oxide synthase activity in these neurons. The treatment with adenovirus encoding CNTF, CT1 or IGF1, however, failed to protect these neurons after avulsion. These results indicate that the gene transfer of GDNF and BDNF and TGFbeta2 but not CNTF, CT1 or IGF1 may prevent the degeneration of motoneurons in adult humans with motoneuron injury and motor neuron diseases.     

Dopamine D3 receptor-preferring agonists induce neurotrophic effects on mesencephalic dopamine neurons

Anti-parkinsonian agents, pramipexole (PPX) and ropinirole (ROP), have been reported to possess neuroprotective properties, both in vitro and in vivo. The mechanisms underlying neuroprotection afforded by the D3-preferring receptor agonists remain poorly understood. The present study demonstrates that incubation of primary mesencephalic cultures with PPX and ROP or the conditioned medium from PPX- or ROP-treated primary cultures induced a marked increase in the number of dopamine (DA) neurons in the cultures. Similar effects can be observed after incubating with the conditioned medium derived from PPX- and ROP-treated substantia nigra astroglia. Meanwhile, PPX and ROP can protect the primary cells from insult of 1-methyl-4-phenylpyridinium (MPP+), the active metabolite of the neurotoxin 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP). Furthermore, the neurotrophic effects of PPX and ROP on mesencephalic dopamine neurons could be significantly blocked by D3 receptor antagonist, but not by D2 receptor antagonist. Moreover, we found that the levels of glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) in the conditioned medium of mesencephalic cultures treated with PPX and ROP were significantly increased. Blocking GDNF and BDNF with the neutralizing antibodies, the neurotrophic effects of PPX and ROP were greatly diminished. These results suggest that D3 dopamine receptor-preferring agonists, PPX and ROP, exert neurotrophic effects on cultured DA neurons by modulating the production of endogenous GDNF and BDNF, which may participate in their neuroprotection.     

Immunosuppressive (FK506) and non-immunosuppressive (GPI1046) immunophilin ligands activate neurotrophic factors in the mouse brain

Based on the fact that several recent reports have indicated that non-immunosuppressive immunophilin ligands (IPLs) can activate neurite outgrowth or nerve regeneration, we investigated the neurotrophic factor-activating abilities of IPLs in vivo in order to clarify the molecular basis of neurotrophic-like activity. Both FK506 (an immunosuppressive IPL) and GPI1046 (a non-immunosuppressive IPL) significantly increased glial cell line-derived neurotrophic factor (GDNF) content in the substantia nigra. In addition, FK506 increased striatal brain-derived neurotrophic factor (BDNF) content significantly. Thus, our present results suggest that the molecular basis of IPL-induced neurotrophic-like activity may be dependent on GDNF and/or BDNF activation.     

Peripheral nerve avulsion injuries as experimental models for adult motoneuron degeneration

We have used adult rat peripheral nerve avulsion models to evaluate the effects of neuroprotective molecules on motoneuron degeneration. The right facial nerves of adult Fischer 344 male rats were avulsed and adenoviral vectors encoding glial cell line‐derived neurotrophic factor (GDNF), brain‐derived neurotrophic factor (BDNF), transforming growth factor‐β2 (TGFβ2), and growth inhibitory factor (GIF) were injected into the facial canal. The treatment with the vectors significantly prevented the loss of lesioned facial motoneurons, improved choline acetyltransferase (ChAT) immunoreactivity and suppressed the induction of nitric oxide synthase activity in these neurons. In separate experiments, animals were orally administered a solution of a neuroprotective compound T‐588 after avulsion. Both free oral administration and oral tube administration of T‐588 improved the survival of injured motoneurons and ameliorated their ChAT immunoreactivity. These results indicate that the gene transfer of GDNF, BDNF, TGFβ2, and GIF and oral administration of T‐588 may prevent the degeneration of motoneurons in adult humans with motoneuron injury and motor neuron diseases.     

Increased plasma levels of BDNF and inflammatory markers in Alzheimer's disease

Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Neurotrophic factors and inflammatory markers may play considerable roles in AD. In this study we measured, through Enzyme-Linked Immunosorbent Assay, the plasma levels of brain derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF) and neuronal growth factor (NGF), as well as tumor necrosis factor-alpha soluble receptors, sTNFR1 and sTNFR2, and soluble intercellular adhesion molecule 1 (sICAM-1), in 50 AD patients, 37 patients with mild cognitive impairment (MCI) and 56 healthy elderly controls. BDNF levels, expressed as median and interquartile range, were higher for AD patients (2545.3, 1497.4–4153.4 pg/ml) compared to controls (1503.8, 802.3–2378.4 pg/ml), P < 0.001. sICAM-1 was also higher in AD patients. sTNFR1 levels were increased in AD when compared to controls and also to MCI. GDNF, NGF and sTNFR2 levels showed no significant differences among the studied groups. The increase in BDNF might reflect a compensatory mechanism against early neurodegeneration and seems to be related to inflammation. sTNFR1 appears to mark not only the inflammatory state but also differentiates between MCI and AD, which may be an additional tool for differentiating degrees of cognitive impairment.     

Bone mesenchymal stromal cells stimulate neurite outgrowth of spinal neurons by secreting neurotrophic factors

Abstract

It has been demonstrated that bone mesenchymal stromal cells (BMSCs) stimulate neurite outgrowth from dorsal root ganglion (DRG) neurons. The present in vitro study tested the hypothesis that BMSCs stimulate the neurite outgrowth from spinal neurons by secreting neurotrophic factors. Spinal neurons were cocultured with BMSCs, fibroblasts and control medium in a non-contact system. Neurite outgrowth of spinal neurons cocultured with BMSCs was significantly greater than the neurite outgrowth observed in neurons cultured with control medium or with fibroblasts. In addition, BMSC-conditioned medium increased the length of neurites from spinal neurons compared to those of neurons cultured in the control medium or in the fibroblasts-conditioned medium. BMSCs expressed brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF). The concentrations of BDNF and GDNF in BMSC-conditioned medium were 132±12 and 70±6 pg ml^?1, respectively. The addition of anti-BDNF and anti-GDNF antibodies to BMSC-conditioned medium partially blocked the neurite-promoting effect of the BMSC-conditioned medium. In conclusion, our results demonstrate that BMSCs promote neurite outgrowth in spinal neurons by secreting soluble factors. The neurite-promoting effect of BMSCs is partially mediated by BDNF and GDNF.     

Altered serum levels of vascular endothelial growth factor and glial-derived neurotrophic factor but not fibroblast growth factor-2 in treatment-naive children with attention deficit/hyperactivity disorder

Abstract

Background and aim: Recent evidence suggests that growth factors might be involved in the pathophysiology of attention deficit hyperactivity disorder (ADHD). The aim of this study was to determine whether serum levels of brain-derived neurotrophic factor (BDNF), glial-derived neurotrophic factor (GDNF), neurotrophin-3 (NT-3), nerve growth factor (NGF), fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF) were altered in children with ADHD.

Methods: Serum levels of BDNF, GDNF, NT-3, NGF, VEGF and FGF-2 were analyzed in 49 treatment- naive children with ADHD and age, gender matched 36 healthy controls using enzyme-linked immunosorbent assay. ADHD symptoms were scored by Du Paul ADHD Rating Scale and Strengths and Difficulties Questionnaire.

Results: We found that serum VEGF levels were significantly lower (p?<?0.001) and GDNF levels were significantly higher in ADHD group compared to control group (p?=?0.003). However, we found no correlations between ADHD symptoms and serum VEGF or GDNF levels. Furthermore, we observed no significant alterations in serum BDNF, NT-3, NGF, FGF-2 levels in children with ADHD.

Conclusion: To our knowledge, the present study is the first to examine serum VEGF and FGF-2 levels in children with ADHD. Our results indicate that VEGF and GDNF might be involved in the etiology of ADHD. Further studies are required to determine the role of growth factors in the etiology and consequently in the treatment of ADHD.     

Brain-derived neurotrophic factor-mediated effects on mitochondrial respiratory coupling and neuroprotection share the same molecular signalling pathways

Intracerebral injection of ibotenate into mouse pups induced grey matter lesions and white matter cysts; co-administration of brain-derived neurotrophic factor (BDNF) produced a dose-dependent reduction in these lesions. In contrast, glial cell line-derived neurotrophic factor (GDNF) had no significant effect, whereas nerve growth factor (NGF) or interleukin-1β (IL-1β) resulted in dose-dependent exacerbation. The neuroprotective effects of BDNF were abolished by co-administration of anti-BDNF antibody or MEK inhibitors, or ABT-737, a BH3 mimetic and Bcl-2 antagonist. The actions of BDNF, GDNF and NGF were measured in a parallel in vitro study on the oxidative metabolism of mouse brain mitochondria. BDNF produced a concentration-dependent increase in the respiratory control index (RCI, a measure of respiratory coupling efficiency, ATP synthesis, and organelle integrity) when co-incubated with synaptosomes containing signal transduction pathways; but GDNF failed to modify RCI, and NGF had only weak effects. BDNF had no effect on pure mitochondria, and enhanced oxidation only when complex I substrates were used. The effect of BDNF was inhibited by anti-BDNF antibody, MEK inhibitors or ABT-737, and also by IL-1β, indicating that the mitochondrial effects are mediated via the same MEK-Bcl-2 pathway as the neuroprotection. The complex I inhibitor rotenone, a compound implicated in the aetiology of Parkinson's disease, inhibited both the in vitro mitochondrial and in vivo neuroprotective effects of BDNF. The ability of BDNF to modify brain metabolism and the efficiency of oxygen utilization via a MEK-Bcl-2 pathway may be an important component of the neuroprotective action observed with this neurotrophin.     

Hydrophobic dipeptide Leu-Ile protects against neuronal death by inducing brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor synthesis

We investigated whether certain hydrophobic dipeptides, Leu-Ile, Leu-Pro, and Pro-Ile, which partially resemble the site on FK506 that binds to immunophilin, could stimulate glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) synthesis in cultured neurons and found only Leu-Ile to be an active dipeptide. Leu-Ile protected against the death of mesencephalic neurons from wild-type mice but not from mice lacking the BDNF or GDNF gene. Next, we examined the effects of i.p. or i.c.v. administration of Leu-Ile on BDNF and GDNF contents. Both types of administration increased the contents of BDNF and GDNF in the striatum of mice. Also, peripheral administration of Leu-Ile inhibited dopaminergic (DA) denervation caused by unilateral injection of 6-hydroxydopamine (6-OHDA) into the striatum of mice. The number of rotations following a methamphetamine challenge was lower in the Leu-Ile-treated group than in the nontreated group. Next, we compared the calcineurin activity and immunosuppressant activity of Leu-Ile with those of FK506. Leu-Ile was not inhibitory toward calcineurin cellular activity in cultured neuronal cells. Furthermore, Leu-Ile did not suppress concanavalin A (ConA)-induced synthesis/secretion of interleukin-2 by cultured spleen cells, suggesting that the immunosuppressant activity of Leu-Ile may be negligible when used as a therapeutic tool for neurodegenerative diseases.     

抑郁发作自杀未遂患者脑源性神经营养因子水平及其相关因素研究

目的 探讨脑源性神经营养因子(BDNF)在抑郁发作自杀未遂者中的可能作用.方法 对抑郁发作自杀未遂患者(自杀未遂组,23例)和抑郁发作无自杀行为患者(无自杀组,24例)采用汉密尔顿抑郁量表(24项,HAMD24)、Beck绝望量表(BHS)和自杀意念自评量表(SIOSS)评定抑郁严重程度、绝望程度及自杀意图的强烈程度;采用酶联免疫吸附法测定其血清BDNF浓度,并与正常对照者(对照组,30名)比较;对自杀未遂组的血清BDNF浓度与各相关因素进行Pearson相关分析.结果 (1)自杀未遂组的HAMD24[(37.8±8.7)分]、BHS[(13.0±3.8)分]及SIOSS评分[(18.1±3.9)分]均高于无自杀组[分别为(26.0±6.0)分、(7.5±4.3)分、(12.0±4.0)分;P<0.01].(2)自杀未遂组的BDNF平均浓度[(57 ±16)ng/L]低于无自杀组[(75 ±28)ng/L;P<0.05],无自杀组的BDNF平均浓度亦低于正常对照组[(111±39)ng/L;P<0.01].(3)自杀未遂组的血清BDNF浓度与抑郁发作的病程(r=-0.541)、BHS总分(r=-0.494)、SIOSS总分(r=-0.754)呈负相关(P<0.01-0.05).结论 低水平的BDNF可能是抑郁发作自杀未遂的一个危险因素.     

Intrathecal injection of GDNF and BDNF induces immediate early gene expression in rat spinal dorsal horn

Glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) are potent trophic factors for dorsal root ganglion cells. In addition, these factors are produced in subsets of dorsal root ganglion cells and transported anterogradely to their terminals in the superficial dorsal horn of the spinal cord, where they constitute the only source of GDNF and BDNF. We investigated the effect of 10 mug GDNF and BDNF injected by lumbar puncture on the expression of the immediate early gene (IEG) products c-Fos, c-Jun, and Krox-24 in the adult rat dorsal horn. In the dorsal horn of S1 spinal segments, GDNF and BDNF induced a strong increase in IEG expression, which was most pronounced in laminae I and II (2.9- to 4.5-fold). More distal from the injection site, in the dorsal horn of L1/L2 spinal segments, the increase in IEG expression was less pronounced, suggesting a concentration-dependent effect. In order to explain the effects of intrathecally injected GDNF, we investigated whether lumbo-sacral dorsal horn neurons expressed RET protein, the signal-transducing element of the receptor complex for GDNF. It was found that several of these neurons contained RET immunoreactivity and that some of the RET-labeled neurons had the appearance of nociceptive-specific cells, confirming their presumed role in pain transmission. Additionally, using double-labeling immunofluorescence combined with confocal microscopy, it was found that after intrathecal GDNF injection 35% of c-Fos-labeled cells were also labeled for RET. These results demonstrate that intrathecally administered GDNF and BDNF induce IEG expression in dorsal horn neurons in the adult rat, supposedly by way of their cognate receptors, which are present on these neurons. We further suggest that the endogenous release of GDNF and BDNF, triggered by nociceptive stimuli, is involved in the induction of changes in spinal nociceptive transmission as in various pain states.     

慢性失眠患者血清神经营养因子改变及其与睡眠质量和认知功能的关系

目的探讨慢性失眠患者血清脑源性神经营养因子(BDNF)和胶质源性神经营养因子(GDNF)水平的变化及其与睡眠质量和认知功能间的关系。方法纳入2017年5月至2018年7月安徽医科大学附属巢湖医院睡眠障碍科就诊的慢性失眠患者57例,以同期本院健康体检中心的30名健康体检者作为对照。采用匹兹堡睡眠质量指数(PSQI)评估受试者的失眠程度(部分慢性失眠患者接受整夜多导睡眠监测),采用蒙特利尔认知评估量表(MoCA)评估总体认知功能,采用九盒迷宫评估特殊记忆功能,ELISA检测受试者的血清BDNF和GDNF水平。结果慢性失眠患者的PSQI得分显著高于对照组[慢性失眠组(14.0±2.2)分,对照组(3.9±1.1)分;t=28.093,P<0.01],MoCA评分显著低于对照组[慢性失眠组(24.5±3.6)分,对照组(26.5±0.9)分;t=-2.985,P<0.01],同时物体工作[慢性失眠组1.0(0,1.0),对照组0(0,0.3)]、空间工作[慢性失眠组3.0(2.0,4.0),对照组1.0(1.0,2.0)]、物体再认记忆[慢性失眠组0(0,0),对照组0(0,0)]错误数高于对照组(Z=-2.896、-5.007、-2.306,均P<0.05)。慢性失眠患者血清BDNF[慢性失眠组(19.48±7.50)ng/ml,对照组(46.49±13.33)ng/ml]和GDNF[慢性失眠组(32.76±14.04)pg/ml,对照组(59.63±20.30)pg/ml]水平显著低于对照组(t=-10.274、-7.240,均P<0.01),与PSQI得分呈负相关(r=-0.293、-0.320,均P<0.05),与MoCA评分呈正相关(r=0.331、0.295,均P<0.05)。BDNF还与病程和空间工作记忆错误数呈负相关(r=-0.319、-0.393,均P<0.05),GDNF与多导睡眠监测中总睡眠时间呈正相关(r=0.520,P<0.05)。结论慢性失眠患者的血清BDNF和GDNF水平较正常人降低,并与其睡眠质量和认知功能损害相关。     

Intracerebroventricular administration of an endothelin ETB receptor agonist increases expressions of GDNF and BDNF in rat brain

Endothelins (ETs) are suggested to be involved in functional alterations of astrocytes after brain injury, including proliferation, hypertrophy and production of neurotrophic factors. In this study, effects of Ala1,3,11,15-endothelin-1 (Ala1,3,11,15-ET-1), an ETB receptor selective agonist, on neurotrophic factor production were examined in rat brain. A continuous intracerebroventricular administration of Ala1,3,11,15-ET-1 (500 pmol/day for 7 days) increased the numbers of GFAP- and vimentin-positive astrocytes in the hippocampus, caudate putamen and cerebrum. Ala1,3,11,15-ET-1 did not induce neuronal degeneration and activation of microglia/macrophage in these brain regions. The intracerebroventricular administration of Ala1,3,11,15-ET-1 for 7 days caused two- to three-fold increases in glial cell line-derived neurotrophic factors (GDNF) mRNA in the hippocampus and cerebrum. The mRNA levels of brain-derived neurotrophic factors (BDNF) in caudate putamen were increased by Ala1,3,11,15-ET-1. Expressions of nerve growth factor (NGF) and basic fibroblast growth factor (bFGF) mRNA in these regions were not largely affected by Ala1,3,11,15-ET-1, except cerebral NGF mRNA level was increased. The Ala1,3,11,15-ET-1-induced increases in GDNF and BDNF mRNA levels were accompanied by increases in immunoreactive GDNF and BDNF. Immunohistochemical observations showed that GFAP-positive astrocytes expressed GDNF and BDNF in the brain regions of Ala1,3,11,15-ET-1-infused rats. In cultured rat astrocytes, Ala1,3,11,15-ET-1 (100 nm) increased mRNA levels of GDNF and BDNF. These results suggest that activation of brain ETB receptors induced GDNF and BDNF expression in astrocytes.     

Reduced serum levels of brain-derived neurotrophic factor in adult male patients with autism

BACKGROUND: The precise mechanisms underlying the pathophysiology of autism are currently unknown. Given the key role of brain-derived neurotrophic factor (BDNF) in brain development, we hypothesized that BDNF may play a role in the pathophysiology of autism. In this study, we studied whether serum levels of BDNF are altered in patients with autism. METHODS: We measured serum levels of BDNF in 18 adult male patients with autism and 18 age-matched healthy male control subjects. RESULTS: The serum levels of BDNF in patients with autism (25.6+/-2.15 ng/ml (mean+/-S.D.)) were significantly (z = -4.42, p < 0.001) lower than those of normal controls (61.6+/-10.9 ng/ml (mean+/-S.D.)). Nevertheless, we found no correlations between BDNF levels and clinical variables in autistic patients. CONCLUSIONS: This study suggests that reduced BDNF levels may play a role in the pathophysiology of autism.     

Growth responses of different subpopulations of adult sensory neurons to neurotrophic factors in vitro

Different subpopulations of adult primary sensory neurons in the dorsal root ganglia express receptors for different trophic factors, and are therefore potentially responsive to distinct trophic signals. We have compared the effect of the neurotrophins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and NT-3, and of glial cell line-derived neurotrophic factor (GDNF) on neurite outgrowth in dissociated cultures of sensory neurons from the lumbar ganglia of young adult rats, and attempted to establish subset-specific effects of these trophic factors. We analysed three parameters of neurite growth (percentage of process-bearing neurons, length of longest neurite and total neurite length), which may correlate with particular types of axon growth in vivo, and may therefore respond differently to trophic factor presence. Our results showed that percentage of process-bearing neurons and total neurite length were influenced by trophic factors, whilst the length of the longest neurite was trophic factor independent. Only NGF and GDNF were found to enhance significantly the proportion of process-bearing neurons in vitro. GDNF was more effective than NGF on small, IB4- neurons, which are known to develop GDNF responsiveness early in postnatal development. NGF, and to a much lesser extent GDNF, enhanced the total length of the neurites produced by neurons in culture. BDNF exerted an inhibitory effect on growth, and both BDNF and NT-3 could partially block some of the growth-promoting effects of NGF on specific neuronal subpopulations.     

Decreased galanin serum levels are associated with alcohol-craving during withdrawal

Background

The hypothalamic galanin expression has been associated with increased intake of carbohydrates and fats in preclinical studies. The appetite stimulating effect of galanin is thought to underlie the positive association between alcohol consumption and hypothalamic galanin expression observed in preclinical studies.

Methods

In this pilot study we investigated alterations in galanin serum levels (33 male patients) in alcohol-dependent patients during alcohol withdrawal (days 1, 7 and 14) in comparison to healthy controls (19 male controls). In order to assess the putative association between appetite regulation, galanin serum levels and alcohol consumption we additionally investigated the serum levels of insulin, glucose and triglycerides.

Results

The galanin serum levels on day 1 of alcohol withdrawal were significantly reduced in the alcohol-dependent patients (T = − 3.302, p = 0.002) and increased significantly from day 1 to day 14 of alcohol withdrawal (F = 6.437, p = 0.002). We found a significant negative association between the galanin serum levels and alcohol craving measured by the Obsessive Compulsive Drinking Scale (OCDS) (r=−0.449, p=0.009) and the obsessive subscale of the OCDS (r = − 0.521, p = 0.002) on day 1 of alcohol withdrawal. There was no association between the galanin serum levels and the parameters of energy homeostasis (triglycerides, cholesterol, insulin, and glucose) investigated.

Conclusions

Acute alcohol withdrawal was associated with decreased galanin serum levels in this pilot study. There was no association between the galanin serum levels and the parameters of energy homeostasis. Further research of galanin serum levels in active drinkers will be necessary to clarify the putative association between galanin serum levels, appetite regulation and alcohol consumption.     

Role of BDNF and GDNF in drug reward and relapse: A review

Brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) are neurotrophic factors that are critical for the growth, survival, and differentiation of developing neurons. These neurotrophic factors also play important roles in the survival and function of adult neurons, learning and memory, and synaptic plasticity. Since the mid-1990s, investigators have studied the role of BDNF and GDNF in the behavioral effects of abused drugs and in the neuroadaptations induced by repeated exposure to drugs in the mesocorticolimbic dopamine system. Here, we review rodent studies on the role of BDNF and GDNF in drug reward, as assessed in the drug self-administration and the conditioned place preference procedures, and in drug relapse, as assessed in extinction and reinstatement procedures. Our main conclusion is that whether BDNF or GDNF would facilitate or inhibit drug-taking behaviors depends on the drug type, the brain site, the addiction phase (initiation, maintenance, or abstinence/relapse), and the time interval between site-specific BDNF or GDNF injections and the reward- and relapse-related behavioral assessments.     

Increased expression of glial cell line-derived neurotrophic factor mRNA in muscle biopsies from patients with amyotrophic lateral sclerosis

The expression of glial cell line-derived neurotrophic factor (GDNF) mRNA and brain-derived neurotrophic factor (BDNF) mRNA were studied in muscle biopsies from five patients with amyotrophic lateral sclerosis (ALS), six patients with other neuromuscular diseases and eight healthy control persons. All five patients with ALS had higher GDNF mRNA expressions in their biopsies than the healthy control group (almost a three fold increase). Among the other patients only one, who had a rapidly progressing toxic polyneuropathy, showed a GDNF mRNA expression above those of the controls. The BDNF mRNA expressions in the biopsies from the ALS patients were in the same range as those from the healthy controls, although the mean value of the ALS patients was higher. The only biopsy that showed a markedly higher BDNF mRNA expression was taken from one patient with progressive muscular atrophy. These results suggest that increased GDNF mRNA expression in muscle is an unspecific response to ongoing denervation and that this response is maintained in ALS, at least temporarily. If increased GDNF mRNA in muscle proves to be a constant finding in ALS the rationale for the use of GDNF as a therapeutic agent in ALS must be questioned.