A case of polyneuropathy associated with increased levels of vascular endotherial growth factor (VEGF) insera]

A 54-year-old woman began to notice numbness and motor weakness in the lower extremities in July 1999. These symptoms rapidly progressed and she could not walk any more. When she admitted to our hospital, she showed peripherally dominant, moderate motor weakness, drop foot and loss of superficial and deep sensation in the lower extremities, but only slight weakness in the hands. Cranial nerves were intact. Deep tendon reflexes were all absent. Nerve conduction velocities were reduced and cerebrospinal fluid protein was elevated. VEGF was greatly increased in serum (1,850 pg/ml), which has been found to be increased exclusively in patients with Crow-Fukase syndrome. Many characteristic manifestations of the syndrome except polyneuropathy are well explained to be resulted from the abnormal production of VEGF. She did not, however, exhibit any constellation of Crow-Fukase syndrome such as edema, skin change, organomegaly, bone lesions or M-proteinemia. Steroid therapy improved her symptoms and lessened the levels of serum VEGF and cerebrospinal fluid protein. This case indicated that overproduction of VEGF could induce polyneuropathy rather than the other symptoms of Crow-Fukase syndrome, and that a polyneuropathy associated with increased VEGF might exist.     

Low plasma vascular endothelial growth factor (VEGF) associated with completed suicide

Abstract

Objectives. Immunological differences have previously been associated with depression and suicidal behaviour. Several cytokines have been identified as potentially important in understanding the pathophysiology of mood disorders and suicidality. Here we aimed to identify new inflammatory biomarkers for suicide prediction. Methods. Plasma concentrations of interleukin (IL) 1-a , IL1-b, IL-2, IL-4, IL-6, IL-8, IL-10, interferon-gamma (IFNG), tumor necrosis factor-a (TNF-a), monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF), and vascular endothelial growth factor (VEGF) were measured in 58 suicide attempters with a high throughput automated biochip immunoassay system. Patients were evaluated using the Montgomery–Åsberg Depression Rating Scale (MADRS) and the Suicide Intent Scale (SIS). All patients were followed up for cause of death. Results. We found significantly lower levels of VEGF in the seven patients who upon a mean follow-up of 13 years were found to have completed suicide. VEGF also showed a trend for negative correlation with the planning subscale of SIS. A trend could be shown for lower IL-2 and for higher IFNG levels in suicide victims. Conclusions. Our study provides further support for a role of inflammation in the pathophysiology of suicidality. VEGF may be related with suicide risk.     

Increased vascular endothelial growth factor (VEGF) is causative in Crow-Fukase syndrome]

Crow-Fukase syndrome is a rare multisystem disorder characterized by polyneuropathy, organomegaly, endocrinopathy, skin changes and M-protein. We have examined levels of vascular endothelial growth factor/vascular permeability factor (VEGF) in serum with Crow-Fukase patients. Serum VEGF levels in Crow-Fukase syndrome were about 15 to 30 times higher than control and other neurological disorders. Most of the characteristic manifestations may be well explainable by the biological function of VEGF except polyneuropathy. We examined the direct effects of VEGF on blood nerve barrier function using blood brain barrier model of rat and intraneural injection of recombinant VEGF. As the result, VEGF affected blood nerve barrier and increased microvascular permeability, thereby inducing endoneurial edema. After increasing the permeability of the blood nerve barrier by VEGF, serum components toxic to nerves such as complements and thrombins may induce nerve damage. Our results suggest that overproduction of VEGF plays an important role in the pathogenesis of Crow-Fukase syndrome.     

Enhancement of sciatic nerve regeneration after vascular endothelial growth factor (VEGF) gene therapy

F. R. Pereira Lopes, B. C. G. Lisboa, F. Frattini, F. M. Almeida, M. A. Tomaz, P. K. Matsumoto, F. Langone, S. Lora, P. A. Melo, R. Borojevic, S. W. Han and A. M. B. Martinez (2011) Neuropathology and Applied Neurobiology 37, 600–612 Enhancement of sciatic nerve regeneration after vascular endothelial growth factor (VEGF) gene therapy Aims: Recent studies have emphasized the beneficial effects of the vascular endothelial growth factor (VEGF) on neurone survival and Schwann cell proliferation. VEGF is a potent angiogenic factor, and angiogenesis has long been recognized as an important and necessary step during tissue repair. Here, we investigated the effects of VEGF on sciatic nerve regeneration. Methods: Using light and electron microscopy, we evaluated sciatic nerve regeneration after transection and VEGF gene therapy. We examined the survival of the neurones in the dorsal root ganglia and in lumbar 4 segment of spinal cord. We also evaluated the functional recovery using the sciatic functional index and gastrocnemius muscle weight. In addition, we evaluated the VEGF expression by immunohistochemistry. Results: Fluorescein isothiocyanate‐dextran (FITC‐dextran) fluorescence of nerves and muscles revealed intense staining in the VEGF‐treated group. Quantitative analysis showed that the numbers of myelinated fibres and blood vessels were significantly higher in VEGF‐treated animals. VEGF also increased the survival of neurone cell bodies in dorsal root ganglia and in spinal cord. The sciatic functional index and gastrocnemius muscle weight reached significantly higher values in VEGF‐treated animals. Conclusion: We demonstrate a positive relationship between increased vascularization and enhanced nerve regeneration, indicating that VEGF administration can support and enhance the growth of regenerating nerve fibres, probably through a combination of angiogenic, neurotrophic and neuroprotective effects.     

Possible gender-dependent association of vascular endothelial growth factor (VEGF) gene and ALS

Individuals homozygous for haplotypes -2578-A/-1154-A/-634-G or -2578-A/-1154-G/-634-G in the promoter/5'UTR of the VEGF gene have a 1.8-fold increased risk of ALS in several European populations. We did not observe any significant association with single markers, or haplotype pairs, in a German sample of 580 sporadic ALS patients and 628 controls. However, the promoter SNP-1154 (rs1570360) was associated with affection status in women (p = 0.036), suggesting that the VEGF effect may be dependent on the sex ratio of the sample.     

Association of cerebral microbleeds in acute ischemic stroke with high serum levels of vascular endothelial growth factor

OBJECTIVE To determine whether vascular endothelial growth factor (VEGF) levels are associated with the presence of cerebral microbleeds (CMBs) in patients after acute ischemic stroke. DESIGN A cross-sectional study that used blood samples obtained within 24 hours of symptom onset from patients who experienced acute stroke to measure VEGF levels by enzyme immunoassay. A validated CMB rating scale was used to analyze acutely acquired magnetic resonance images, with the rater blind to clinical details and VEGF levels. SETTING Accident and Emergency Department at University College Hospital, London, England. PATIENTS Twenty patients who experienced acute ischemic stroke. MAIN OUTCOME MEASURES Presence of CMBs and serum level of VEGF. RESULTS Five of the 20 patients with acute ischemic stroke (25%) had CMBs. The median VEGF level in the CMB group was significantly higher than that in the group without CMBs (P?=?.003). CONCLUSION An increase in vascular permeability secondary to a raised VEGF level may have a role in the genesis of CMBs in patients with acute ischemic stroke.     

Immunohistochemical detection of vascular endothelial growth factor (VEGF) in the vasculature of oligodendrogliomas

C. Christov, H. Adle-Biassette, C. Le Guerinel, S. Natchev and R. K. Gherardi (1998) Neuropathology and Applied Neurobiology 24, 29–35 Immunohistochemical detection of vascular endothelial growth factor (VEGF) in the vasculature of oligodendrogliomas Vascular endothelial growth factor (VEGF) appears to be implicated in tumour angiogenesis. In the present study immunohistochemical expression of VEGF was evaluated in 34 oligodendrogliomas (13 grade II, 21 grade III [WHO]). VEGF immunoreactivity was found in 31 of 34 cases. Expression of VEGF was observed in endothelial cells and some vascular smooth muscle cells, but not in neoplastic oligodendrocytes. Vessel counts, percentages of VEGF-positive vessels and vessels with vascular endothelial proliferation were assessed. The degree of VEGF labelling and vascular-endothelial proliferation in each vessel were evaluated using a 3 degree intensity score. Expression of VEGF was higher in grade III than in grade II oligodendrogliomas as assessed by percentage of VEGF positive vessels (55.8 ± 29.2% vs 17.0 ± 19.0% [P < 0.001]) and by VEGF immunostaining intensity (1.90 ± 0.60 vs 0.90 ± 0.40 [P < 0.001]). VEGF expression did not correlate with vessel density. Intensity of VEGF expression correlated positively with that of vascular-endothelial proliferation in grade III tumours (r=+0.47 [P < 0.05]). The percentage of VEGF positive vessels showed some degree of positive correlation with the percentage of vessels showing vascular-endothelial proliferation (r=+408 [P < 0.10]). Within individual grade III tumours 67.5 ± 29.6% of all vessels with vascular-endothelial proliferation were VEGF-positive and 31.0 ± 20.5% of all VEGF-positive vessels showed no evidence of vascular-endothelial proliferation. We conclude that (i) expression of VEGF is observed in the vasculature of oligodendrogliomas; (ii) marked expression of VEGF is observed in grade III oligodendrogliomas; (iii) VEGF may be one of the interrelated causative stimuli acting in concert to induce vascular-endothelial proliferation.     

Expression of vascular endothelial growth factor (VEGF) in rat brain after subarachnoid haemorrhage and endothelin receptor blockage with BQ-123

Cerebral vasospasm is one of the most severe complications of subarachnoid haemorrhage (SAH), leading to pathological changes in the vessel wall itself and in the nervous tissue, due to ischaemia of endothelial cells and neurones. Amongst the known substances inducing vasospasm, the most potent spasmogenic effect is exerted by endothelin-1 (ET1). The constriction of cerebral arteries and obliteration of capillaries highly stimulates the secretion of growth factors by endothelial cells and induces compensatory formation of collateral circulation in response to brain ischaemia. Expression of vascular endothelial growth factor (VEGF), the main factor responsible for angiogenesis and vascular permeability, was found to be increased in hypoxic cells (irrespective of the cause of hypoxia) as well as in neoplastic cells in the brain. The aim of the study was to determine whether chronic vasospasm and hypoxia of endothelial cells stimulate expression of VEGF, and whether blockage of the endothelin receptor ET(A) reduces this expression. The SAH was induced experimentally in male Wistar rats and the ET(A) receptor antagonist--BQ-123 was administered into the cisterna magna. After 48 hours the brain was removed and expression of VEGF studied immunohistochemically on paraffin sections. We found that hypoxia of endothelial cells, induced by chronic vasospasm after SAH, caused increased expression of VEGF in brain vessels and neurones of the cerebral hemispheres, brain stem and cerebellum. After administration of the endothelin receptor antagonist BQ-123, no changes in VEGF expression in the brain were found.     

Vascular endothelial growth factor (VEGF) modulates vascular permeability and inflammation in rat brain.

Vascular endothelial growth factor (VEGF) is an angiogenic growth factor that also induces vascular permeability and macrophage migration. VEGF expression is weak in normal adult brain, but is strongly upregulated in glioma cells and reactive astrocytes, suggesting that chronic overexpression of VEGF in the brain contributes to blood-brain barrier (BBB) breakdown. We examined the effects of chronic VEGF overexposure on the integrity of the BBB using the following approaches: 1) continuous intracerebral infusion of VEGF via miniosmotic pump; and 2) intracerebral injection of an adenoviral vector encoding the VEGF165 gene (AdCMV.VEGF). After 6 days both treatments produced approximately 10-fold breakdown of the BBB (as measured by transport of 14C-aminoisobutyric acid (AIB) from blood into brain) compared with the respective controls (albumin infusion or AdCMV.beta gal virus). BBB disruption in AdCMV.VEGF-treated brains was accompanied by a severe inflammatory response not observed in brains receiving AdCMV.beta gal or VEGF protein infusion, indicating that neither VEGF nor viral particles alone were responsible for the inflammatory response. However, injection of AdCMV.beta gal followed by VEGF infusion to the same site also elicited inflammation. Chronic overexposure of normal brain to VEGF also increased intercellular adhesion molecule-1 (ICAM-1) and major histocompatibility complex (MHC) class I and II expression. Although VEGF itself is not inflammatory, VEGF may modulate immune responses in the central nervous system (CNS) by opening the BBB, altering the immunoprivileged status of the brain, and allowing contact between normally sequestered CNS antigens and blood-borne immune mediators.     

急性脑梗死患者血清血管内皮生长因子的测定

目的　探讨急性脑梗死与血管内皮生长因子 (VEGF)的关系。方法　对 3 0例急性脑梗死患者和 40例健康人血清血管内皮生长因子含量进行测定。患者采血时间为病后第 2天或第 3、4天 ,取均数与对照组比较。结果　 3 0例急性脑梗死患者血清 VEGF含量为 (2 95 .0 4± 3 5 .73 ) pg/ ml,对照组为 (13 7.71± 11.5 3 ) pg/ m l,两组比较差异显著。结论　急性脑梗死患者血清 VEGF升高 ,提示 VEGF是脑梗死急性期的自我保护机制之一。     

Modulation of vascular endothelial growth factor (VEGF) expression in motor neurons and its electrophysiological effects

Previous studies have shown that VEGF expression in forebrain increases after experimental manipulations that increase neuronal activity. One question is whether this also occurs in motor neurons. If so, it could be potentially advantageous from a therapeutic perspective, because VEGF prevents motor neuron degeneration. Therefore, we asked whether endogenous VEGF expression in motor neurons could be modulated. We also asked how VEGF exposure would influence motor neurons using electrophysiology.

Immunocytochemistry showed that motor neuron VEGF expression increased after a stimulus that increases neuronal and motor activity, i.e., convulsive seizures. The increase in VEGF immunoreactivity occurred in all motor neuron populations that were examined 24 h later. This effect was unlikely to be due to seizure-induced toxicity, because silver degeneration stain did not show the typical appearance of a dying or dead neuron.

To address the effects of VEGF on motor neuron function, VEGF was applied directly to motor neurons while recording intracellularly, using a brainstem slice preparation. Exposure to exogenous VEGF (200 ng/ml) in normal conditions depressed stimulus-evoked depolarization of hypoglossal motor neurons. There was no detectable effect of VEGF on membrane properties or firing behavior. We suggest that VEGF is upregulated in neurons when they are strongly activated, and VEGF depresses neuronal excitation as a compensatory mechanism. Failure of this mechanism may contribute to diseases that involve a dysregulation of VEGF, excessive excitation of motor neurons, and motor neuron loss, such as amyotrophic lateral sclerosis (ALS).     

A case of anti-GM1 antibody positive HTLV-I associated myelopathy (HAM) with polyneuropathy]

We report a case of HTLV-I associated myelopathy (HAM) with polyneuropathy. A 59-year old man suffering from progressive paraparesis associated with subclinical polyneuropathy was admitted to our hospital. HTLV-I antibodies in the serum and CSF were positive, and a diagnosis of HAM was made. His laboratory investigation revealed elevated serum IgG and IgM anti GM-1 antibodies. The nerve conduction study showed a mild reduction in motor and sensory conduction velocity in all extremities. A sural nerve biopsy revealed active demyelination and globule-like changes, which are specific for HAM neuropathy. Anti-GM1 antibodies are frequently present in autoimmune motor neuropathy. They are thought to inflict a damage on both the myelin and axons of the peripheral nerves. Ours is believed to be the first case of HAM associated with anti-GM1 antibodies, although polyneuropathy is often associated with HAM. While it is not clear whether the lesion observed in HAM neuropathy results from the direct cytopathic effect of the virus or from the immune response, some immune-mediated reactions are thought to play an important role. This case suggests that a case of HAM with polyneuropathy should be examined for the presence of the anti-ganglioside antibodies. More investigations are needed to fully understand the mechanism of the HAM neuropathy.     

颈动脉粥样硬化性狭窄患者血管内皮生长因子检测及意义

目的探讨颈动脉粥样硬化性狭窄(CAS)患者血管内皮生长因子(VEGF)水平变化。方法用酶联免疫法测定73例颈动脉粥样硬化性狭窄(CAS)患者和40例正常对照组血清中VEGF的水平。结果CAS组VEGF水平均高于正常对照组(P<0.05)。结论颈动脉粥样硬化性狭窄患者的血清VEGF水平明显升高。血清VEGF高水平可能成为CAS出现及以后发展为缺血性脑卒中的预测因素和危险因素之一。     

Rapid antidepressant changes with sleep deprivation in major depressive disorder are associated with changes in vascular endothelial growth factor (VEGF): a pilot study

While conventional antidepressants benefit many patients with major depressive disorder (MDD), as much as eight to 12 weeks can elapse before significant improvements in depressive symptoms are seen. Treatments that act more rapidly in MDD are urgently needed. Sleep deprivation (SD) has been shown to produce a rapid antidepressant response within one day in 50-60% of patients with MDD; thus, identifying its antidepressant mechanism may contribute to the development of antidepressants that act more rapidly. The present study evaluated the effects of 39 h of SD on mood, as well as on plasma levels of brain derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) in patients with MDD. After a drug-free period of at least two weeks, 11 patients (6 males, 5 females; ages 25-62) who met DSM-IV criteria for MDD underwent total SD. Plasma samples for BDNF and VEGF assays were collected on Days 1 (baseline) and 2. The six-item Hamilton Rating Scale for Depression (HAMD-6) was the primary outcome measure. HAMD-6 scores decreased significantly after SD (Day 2). SD was negatively correlated with change in HAMD-6 score and change in VEGF levels, indicating that as depression scores decreased following SD, VEGF plasma levels increased. In contrast, SD did not alter plasma BDNF concentrations, nor was an association found between BDNF levels and clinical improvement on the HAMD-6. These results suggest that SD is associated with mood-related changes in plasma VEGF levels, but not plasma BDNF levels. Further studies using larger sample sizes are needed to confirm these preliminary findings.     

Vascular endothelial growth factor (VEGF) is increased in serum, but not in cerebrospinal fluid in HIV associated CNS diseases

Vascular endothelial growth factor (VEGF) is a potent angiogenic and mitogenic peptide, which also induces several mediators that may play a role in HIV induced CNS damage. VEGF levels were determined in cerebrospinal fluid (CSF) and serum samples from patients with (n = 8) and without (n = 19) directly HIV associated CNS disorders and HIV negative control patients (n = 18). VEGF serum but not CSF levels were significantly increased in HIV infected patients with (381.1 (78.9) pg/ml) HIV associated CNS diseases compared with those without (120.8 (13.1) pg/ml) and HIV negative control patients (133.1(14.8) pg/ml). Serum samples from patients with untreated HIV associated encephalopathy (HIVE, n = 3) contained the highest VEGF levels (583.9 (71.5) pg/ml). In two patients VEGF serum levels were reduced during antiretroviral therapy. However, regardless of effective viral suppression, patients with HIVE still had higher levels compared with HIV infected patients without HIVE. A relevant increase of serum VEGF was not observed in patients without HIVE though high HI viral load. We conclude that HIVE is associated with increased serum VEGF levels. Further studies are warranted to elucidate the role of VEGF in HIVE.     

急性脑梗死患者血清VEGF与bFGF水平的动态变化

目的探讨急性脑梗死患者血清血管内皮生长因子(VEGF)与碱性成纤维细胞生长因子(bFGF)水平的动态变化及其临床意义。方法应用ELISA法检测120例急性脑梗死患者(脑梗死组)发病2 d内、7 d、14d和60例健康体检者(对照组)血清VEGF和bFGF水平,利用头部CT或MRI测量梗死灶最大直径,3个月后用改良的Rankin量表评分(mRS)评估患者预后。结果 (1)急性脑梗死组患者于发病后2 d内、7 d、14 d的血清VEGF和bFGF水平明显高于对照组(P0.01),且在急性期VEGF水平持续升高,高峰发生在7 d,以后逐渐下降,至14 d仍维持在较高水平;血清bFGF水平在发病后2 d内达高峰,发病7 d呈逐渐下降趋势,14 d仍高于正常。(2)血清VEGF和bFGF水平与脑梗死面积有关,血清VEGF和bFGF水平愈高,脑梗死面积愈大(P0.01)。(3)VEGF和bFGF水平与脑梗死的预后有关,VEGF和bFGF越高,预后越好(P0.01)。结论急性脑梗死患者血清VEGF和bFGF浓度的变化与病程、梗死面积大小及脑神经功能恢复情况具有一定的相关性,提示VEGF和bFGF浓度与脑梗死后新血管形成关系密切,二者可作为判断梗死面积与预后的新外周指标。     

Expression of vascular endothelial growth factor by reactive astrocytes and associated neoangiogenesis

Injury to the central nervous system (CNS) invokes a reparative response known as astrogliosis, characterized largely by hypertrophy, proliferation and increased expression of glial fibrillary acidic protein (GFAP), resulting in reactive astrocytosis. Based on our prior observation that peritumoral reactive astrocytes express Vascular Endothelial Growth Factor (VEGF), a highly potent and specific angiogenic growth factor, we have hypothesized that reactive astrocytosis also contributes to the neovascularization associated with astrogliosis. To evaluate this hypothesis we evaluated human surgical/autopsy specimens from a variety of CNS disorders that induce astrogliosis and an experimental CNS needle injury model in wild type and GFAP:Green Fluorescent Protein (GFP) transgenic mice. Using computer image semi-quantitative analysis we evaluated the number of GFAP-positive reactive astrocytes, degree of VEGF expression by these astrocytes, associated Factor VIII-positive microvascular density (MVD) and Ki-67 proliferating endothelial cells. The degree of reactive astrocytosis correlated to levels of VEGF immunoreactivity and MVD in the neuropathological specimens. The mouse-needle-stick brain injury model demonstrated this correlation was temporally and spatially related and maximal after 1 week. These results, involving both human pathology specimens augmented by experimental animal data, supports our hypothesis that the neoangiogenesis associated with reactive astrogliosis is correlated to increased reactive astrocytosis and associated VEGF expression.