Increased hepatocyte growth factor level in cerebrospinal fluid in Alzheimer's disease

BACKGROUND & OBJECTIVE: Hepatocyte growth factor (HGF), also known as the scatter factor, is a potent mitogen for mature hepatocytes, and also has multifunctional effects on some cells in various organs. Recently, we have found expression and localization of HGF in white matter astrocytes in human brain tissues. Furthermore, immunohistochemistry using anti-HGF antibody revealed more intense immunolabeling in Alzheimer's disease (AD) than control brains. The aim of the study is to investigate the level of HGF in cerebrospinal fluid (CSF) from patients with AD. MATERIAL AND METHODS: We examined the level of HGF in CSF from 34 AD and 15 age-matched disease control patients by highly sensitive enzyme-linked immunoabsorbent assay (ELISA) system. RESULTS: Consistent with the immunohistochemical data, a significantly higher concentration of HGF in AD CSF was found as compared with controls. A significant correlation was also seen between CSF HGF levels and white matter high-signal foci determined on brain magnetic resonance imaging (MRI) in AD patients. CONCLUSION: These results indicate that CSF HGF levels correspond with the white matter damage in AD brain.     

Increased levels of neuronal thread protein in cerebrospinal fluid of patients with Alzheimer's disease

Neuronal thread protein is a recently characterized, ～20-kd protein that accumulates in brains with Alzheimer's disease (AD) lesions. This study examined whether concentrations of neuronal thread protein (NTP) were also increased in the cerebrospinal fluid (CSF) of individuals with probable (clinically diagnosed) and definite (histopathologically proved) AD. Using a highly sensitive three-site monoclonal antibody–based immunoradiometric assay, we measured NTP concentrations in CSF from 84 patients with probable AD and mild dementia (duration, 4.05 ± 0.36 years), 45 with Parkinson's disease and minimal or no dementia (duration, 4.73 ± 0.78 years), 73 with multiple sclerosis, and 73 nondemented control subjects. NTP concentrations were also measured in postmortem ventricular fluid and temporal lobe neocortex extracts from 31 subjects with histopathologically proved AD and 14 age-matched control subjects. The mean concentration of NTP in the CSF was higher in AD (4.15 ± 0.25 ng/ml; 95% confidence interval [CI] limits, 3.65–4.65) than in Parkinson's disease (1.96 ± 0.16 ng/ml; 95% CI, 1.65–2.27), multiple sclerosis (1.6 0.14 ng/ml; 95% CI limits, 1.33–1.88), or control subjects (1.27 ± 0.06 ng/ml; 95% CI limits, 1.15–1.40) (p < 0.001). In addition, 70% of the patients with probable AD had concentrations of NTP in CSF that were higher than 2.5 ng/ml (> upper 99% CI limit in the control group), compared with 23%of Parkinson's disease patients, 11% of multiple sclerosis patients, and 40% of control subjects. The mean concentrations of NTP in the ventricular fluid and brain tissue from individuals with documented AD and end-stage dementia were threefold higher than the levels detected in the CSF from the remaining patients with probable AD and mild dementia. Moreover, of 9 patients with AD, postmortem brain and CSF manifested 5- to 50-fold higher levels of NTP compared with the CSF samples obtained an average of 6 years earlier. These findings demonstrate that NTP levels are elevated in the CSF of individuals with AD and that NTP levels in the CSF increase strikingly with progression of dementia and neuronal degeneration.     

Cytokines and chemokines in cerebrospinal fluid and serum of adult patients with acute disseminated encephalomyelitis

Cytokines and chemokines contribute to the pathogenesis of acute disseminated encephalomyelitis (ADEM). Using a multiplex immunochemiluminescence ELISA, we measured 8 Th1/Th2 cytokines and 18 chemokines in the cerebrospinal fluid (CSF) and serum of 17 ADEM patients, 14 multiple sclerosis (MS) patients, and 7 healthy controls (HCs). Relative to HCs, ADEM patients had significantly high mean CSF concentrations of chemokines with attractant/activating properties towards neutrophils (CXCL1 and CXCL7), monocytes/T cells (CCL3 and CCL5), Th1 cells (CXCL10), and Th2 cells (CCL1, CCL22, and CCL17). Mean CSF concentrations of CXCL7, CCL1, CCL22, and CCL17 were higher in ADEM than in MS, whereas those of CCL11 were lower in MS than in ADEM and HCs. CSF pleocytosis correlated with CSF concentrations of CXCL1, CXCL10, CCL1, CCL17, and CCL22. Most of the functionally homologous chemokines correlated with each other. CSF Th1/Th2 cytokines were not detectable in most samples. Their mean concentrations did not differ in the three groups, and the same held for serum cytokines and chemokines. Our data suggest that the upregulation of chemokines active on neutrophils and Th2 cells differentiates ADEM from MS inflammation, and that both Th1 and Th2 chemokines might be produced in ADEM. Chemokines upregulated in ADEM could become CSF biomarkers after a posteriori evaluations in unselected case series.     

Tau protein concentrations in the cerebrospinal fluid of children with acute disseminated encephalomyelitis

Background: Acute disseminated encephalomyelitis (ADEM) is clinically characterized by the acute onset of neurological symptoms after a viral infection or immunization, and is thought to represent an autoimmune disease directed against myelin. Tau protein is a phosphorylated microtubule-associated protein, primarily located in neuronal axons. Increased levels of tau protein in cerebrospinal fluid (CSF) are found in various pathological conditions. Methods: We used tau protein as a marker of axonal damage and examined its concentration in the CSF of 27 children with ADEM. Results: CSF tau protein concentration in children with ADEM was significantly higher than that in the CSF of control subjects (P = 0.008). There were no significant differences in CSF tau protein concentrations in the ADEM patients with and without encephalopathy. The CSF tau protein concentration in patients with partial lesion resolution in follow-up brain MRI was significantly higher than in patients with complete lesion resolution (P = 0.014). Conclusions: In conclusion, we demonstrated that CSF tau protein concentration was significantly increased in ADEM patients. Our findings suggest that axonal damage may occur in addition to demyelination in children with ADEM.     

Patterns of cerebrospinal fluid catechols support increased central noradrenergic responsiveness in aging and Alzheimer's disease.

BACKGROUND: High cerebrospinal fluid (CSF) norepinephrine (NE) concentrations in aging and Alzheimer's disease (AD) could reflect decreased NE clearance from central nervous system (CNS) extracellular fluid or increased release of NE into CNS extracellular fluid. Measuring CSF concentrations of the intraneuronal NE metabolite dihydroxyphenylglycol (DHPG), an estimate of NE clearance, and the NE precursor dihydroxyphenylacetic acid (DOPA), an estimate of NE biosynthesis, can help differentiate these mechanisms. METHODS: NE, DHPG, and DOPA were determined by HPLC in CSF and plasma obtained following yohimbine, clonidine, and placebo. Ten AD, 10 older, and 11 young subjects were studied. RESULTS: CSF DOPA following yohimbine was higher in older and AD than in young subjects. CSF DHPG did not differ among groups. Plasma DOPA following yohimbine was higher in AD than in young subjects. CONCLUSIONS: During alpha-2 adrenoreceptor blockade in both aging and AD, there are increased responses of CNS NE biosynthesis and release with unchanged CNS NE clearance. This pattern is consistent with partial loss of CNS noradrenergic neurons with compensatory activation of remaining CNS noradrenergic neurons. Given the marked loss of locus coeruleus (LC) noradrenergic neurons in AD, achievement of high CSF NE suggests particularly prominent compensatory activation of remaining LC neurons in this disorder.     

Interleukin-6 and oligoclonal IgG synthesis in children with acute disseminated encephalomyelitis

Interleukin-6 (IL-6) has a number of roles including recruitment of T lymphocytes and differentiation of B lymphocytes into IgG-secreting plasma cells. Furthermore, IL-6 is a neuropoietic cytokine with effects on neuronal differentiation, function and survival. We studied IL-6 concentrations in children with acute disseminated encephalomyelitis (ADEM; n = 14), and compared the values with those obtained from control patients with other inflammatory (OIND; n = 13) and non-inflammatory (NIND; n = 10) neurological disorders. Patients with ADEM had a significantly increased CSF IL-6 concentration compared with both OIND and NIND groups ( P < 0.01). Serum IL-6 was also increased in the ADEM group compared with the OIND group ( P < 0.05). CSF: serum IL-6 ratios were significantly increased in the ADEM group compared with the NIND group ( P < 0.05), suggesting an intrathecal production of IL-6 rather than its passive transfer across the blood-brain barrier alone. In ADEM, there was a significant correlation between an increased CSF IL-6 and an identical pattern of oligoclonal IgG synthesis in both serum and CSF ( P < 0.05). These results would suggest a role for IL-6 in the pathology of ADEM, and a possible direct link between an increased IL-6 and a proliferation of B lymphocytes with consequent IgG production.     

Elevated CSF prostaglandin E2 levels in patients with probable AD.

OBJECTIVE: To determine CSF eicosanoid concentrations and brain cyclo-oxygenase activity in AD patients and age-matched control subjects. BACKGROUND: Nonsteroidal anti-inflammatory drugs may benefit AD patients by inhibiting cyclo-oxygenases and thereby reducing prostaglandin (PG) production or oxidant stress in the CNS. METHODS: CSF eicosanoid and F2-isoprostane (IsoP) levels were determined in seven probable AD patients and seven age-matched control subjects. Cyclo-oxygenase activity was determined in microsomes prepared from the hippocampus of 10 definite AD patients and 8 age-matched control subjects. All measurements were made using gas chromatography/mass spectrometry. RESULTS: CSF concentrations of prostaglandin (PG) E2 were increased fivefold (p < 0.01) and 6-keto-PGF1alpha was decreased fourfold (p < 0.01) in probable AD patients. There was no change in total CSF eicosanoid concentration in probable AD patients. CSF F2-IsoP, a quantitative marker of lipid peroxidation in vivo, was increased in probable AD patients (p < 0.05). Cyclo-oxygenase activity in the hippocampus from definite AD patients was not different from age-matched control subjects. CONCLUSIONS: These data suggest that cyclo-oxygenase activity may not contribute significantly to CNS oxidative damage in AD. Increased CSF PGE2 concentration in probable AD patients suggest that cyclo-oxygenase inhibitors may benefit AD patients by limiting PG production.     

Elevated cerebrospinal fluid level of ciliary neurotrophic factor in acute disseminated encephalomyelitis

We investigated the concentrations of ciliary neurotrophic factor (CNTF) in cerebrospinal fluid (CSF) from children with inflammatory diseases of the central nervous system. We studied 6 children with acute disseminated encephalomyelitis (ADEM), 14 with acute encephalitis/encephalopathy, 17 with bacterial meningitis, and 24 with aseptic meningitis. We found that CNTF was undetectable in the CSF of all children with acute encephalitis/encephalopathy during the acute and convalescent stages, those with aseptic meningitis, and the 25 control subjects. In children with ADEM, CNTF was undetectable during the acute stage, but its concentration was elevated in all six at the convalescent stage. In children with bacterial meningitis, the CNTF concentration was slightly elevated in two of the 17 during the acute stage and another two at the convalescent stage. Our results suggest that CNTF is part of the regulatory system for oligodendrocyte functions, such as remyelination, in ADEM.     

Reduced CSF PLTP activity in Alzheimer's disease and other neurologic diseases; PLTP induces ApoE secretion in primary human astrocytes in vitro

Phospholipid transfer protein (PLTP) plays a pivotal role in cellular lipid efflux and modulation of lipoprotein metabolism. PLTP is distributed widely in the central nervous system (CNS), is synthesized by glia and neurons, and is active in cerebrospinal fluid (CSF). The aims of this study were to test the hypothesis that patients with Alzheimer's disease (AD) have altered PLTP-mediated phospholipid transfer activity in CSF, and to examine the potential relationship between PLTP activity and apolipoprotein E (apoE) levels in CSF. We assessed PLTP activity and apoE concentration in CSF of patients with probable AD (n = 50), multiple sclerosis (MS; n = 9), other neurologic diseases (n = 21), and neurologically healthy controls (n = 40). PLTP activity in AD was reduced compared to that in controls (P < 0.001), with approximately half of the AD patients with PLTP activity values below all controls. Patients with MS had lower PLTP activity than AD patients (P < 0.001). PLTP activity was highly correlated with PLTP mass, as estimated by Western blot (r = 0.006; P < 0.01). CSF PLTP activity positively correlated with apoE concentration in AD (R = 0.435; P = 0.002) and controls (R = 0.456; P = 0.003). Anti-apoE immunoaffinity chromatography and Western blot analyses indicated that some CSF PLTP is associated with apoE-containing lipoproteins. Exogenous addition of recombinant PLTP to primary human astrocytes significantly increased apoE secretion to the conditioned medium. The findings of reduced PLTP activity in AD CSF, and the observation that PLTP can influence apoE secretion in astrocytes suggest a potential link between alterations in the brain lipid metabolism and AD pathogenesis.     

Cerebrospinal hepatocyte growth factor levels correlate negatively with disease activity in multiple sclerosis

The hepatocyte growth factor (HGF) is a pleiotropic cytokine with neuroprotective and anti-inflammatory properties. Additionally, it enhances axonal outgrowth and oligodendroglial maturation. We studied the expression of HGF by cells derived from cerebrospinal fluid (CSF), quantified HGF in CSF samples and investigated the glial expression of HGF in vitro. We found decreased expression of HGF in CSF cells as well as reduced CSF but not plasma HGF protein levels in MS. MS patients with active disease had lower HGF CSF levels than inactive MS patients, and treatment with Natalizumab correlated with increased CSF concentration of HGF. In vitro, glial production of HGF was reduced by CSF from MS patients in comparison with CSF from controls. CSF levels of CCL2, a known inducer of HGF, also correlated strongly with HGF levels. We conclude that the expression of HGF within the CNS is reflective of disease activity in MS and this may be due to decreased induction of HGF by CCL2. Furthermore, the decreased HGF associated with active disease may potentially contribute to reduced stimulation for remyelination and the occurrence of shadow plaques frequently seen in MS patients. Our results merit further validation to establish whether CSF HGF is a biomarker for MS disease activity.     

24S-hydroxycholesterol in cerebrospinal fluid is elevated in early stages of dementia.

The brain is the most cholesterol-rich organ in the human body. Accumulation of excess cholesterol in hippocampal neurons promotes the cleavage of the amyloid precursor protein (APP) into amyloidogenic components with the consequence of the acceleration of neuronal degeneration. Conversion of cholesterol to 24S-hydroxycholesterol mediated by cholesterol 24S-hydroxylase (CYP46) is the major pathway for the elimination of brain cholesterol and the maintenance of brain cholesterol homeostasis. We examined whether cerebrospinal fluid (CSF) 24S-hydroxycholesterol levels differ between patients with dementia, patients with mild cognitive impairment (MCI), and cognitively intact control subjects. Plasma and CSF concentrations of 24S-hydroxycholesterol and cholesterol in 32 patients with Alzheimer's disease (AD), 11 patients with vascular dementia, seven patients with MCI, and seven cognitively intact control subjects were measured by combined gas-chromatography/mass spectrometry. We show elevated concentrations of 24S-hydroxycholesterol in the CSF of AD patients and we interpret this finding as a consequence of increased cholesterol turnover in the central nervous system during neurodegeneration. The observed influence of the apolipoprotein E epsilon4 (APOE4) allele on CSF 24S-hydroxycholesterol concentrations with a gene-dosage effect suggests the existence of a link between the AD risk factor APOE4 and CNS cholesterol metabolism. The elevation of CSF 24S-hydroxycholesterol appears to occur early in the disease process, since patients with mild cognitive impairment had also increased CSF concentrations of this compound. We believe that the CSF concentration of 24S-hydroxycholesterol is altered in AD-related neurodegeneration and thus, CSF 24S-hydroxycholesterol may be a marker for monitoring the onset and progression of the disease.     

Glutamine synthetase in cerebrospinal fluid, serum, and brain: a diagnostic marker for Alzheimer disease?

OBJECTIVES: To determine whether the glutamine synthetase (GS) level in cerebrospinal fluid (CSF) is a useful biochemical marker in the diagnosis of Alzheimer disease (AD), and to assess the source of GS (brain vs. blood derived) in CSF. METHODS: Sandwich enzyme immunoassay and immunoblotting were applied to detect GS in CSF and in serum from neurologically healthy control subjects and patients with neurodegenerative diseases, including AD. The origin of GS was estimated by the concentration gradients of CSF to serum and ventricular to lumbar CSF. In addition, postmortem brain tissue from controls and patients with AD was analyzed using immunohistochemistry for expression of GS. RESULTS: Levels of GS were significantly increased in lumbar CSF from patients with AD (20+/-12 pg/mL; P = .01) and to a lesser extent in patients with vascular dementia and amyotrophic lateral sclerosis. In CSF of controls, GS levels were 4+/-3 pg/mL. The GS concentration gradients were less than 1:10 for CSF to serum and 2:1 for ventricular to lumbar CSF. Immunoreactivity of GS was most prominent in astrocytes from temporal neocortex of patients with AD, suggesting a relationship between astrocyte reactions and increased GS levels in CSF. CONCLUSIONS: Level of GS in lumbar CSF of patients with AD is increased significantly but nonspecifically, probably related to the strong astrogliosis in brain. Glutamine synthetase in lumbar CSF is mainly brain derived.     

Acute disseminated encephalomyelitis: study of factors involved in a possible development towards multiple sclerosis

Acute disseminated encephalomyelitis (ADEM) is an uncommon disease characterized by inflammation and demyelination of the central nervous system (CNS). It typically occurs after a viral infection or vaccination and is more frequent in children. Its immediate and longterm prognosis is expected to be good (20% of cases with sequelae). Although ADEM is typically monophasic, occasional relapses may occur. Differential diagnosis, mostly in the early phases, is established with multiple sclerosis (MS), a chronic inflammatory demyelinating disease of the CNS that may have worse prognosis. Traditionally it has been believed that 10% of ADEM patients develop MS. However, this percentage could be higher according to several recently published clinical series. Some clinical and paraclinical patterns are considered to confer risk of developing MS when present in ADEM patients. Our study has aimed to: a) describe a series of 29 patients (22 children and 9 adults) admitted in our hospital and diagnosed of ADEM between 1990 and 2005; b) study those patients considered to have risk patterns of developing MS, and c) compare the child and adult populations of our series. After a median 55 month follow-up, 6 children (27%) and no adults developed MS. In our series, risk patterns for developing MS predicted conversion to MS more accurately in children than in adults. Eight patients (6 children and 2 adults) had sequelae, cognitive in 6 of them. Our work supports that also observed in recent publications: that both conversion to MS or presence of sequelae after an episode of ADEM are more frequent than traditionally considered.     

Patterns of levels of biological metals in CSF differ among neurodegenerative diseases

We measured the levels of some biological metals: copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), and zinc (Zn) in the cerebrospinal fluid (CSF) in patients with neurodegenerative diseases (52 patients with amyotrophic lateral sclerosis (ALS)), 21 patients with Alzheimer's disease (AD), and 20 patients with Parkinson's disease (PD) by inductively coupled plasma mass spectrometry (ICP-MS). The diagnoses were additionally supported by neuroimaging techniques for AD and PD. In ALS, the levels of Mg (p<0.01 significant difference), Fe, Cu (p<0.05), and Zn (p<0.10) in CSF were higher than those in controls. Some patients showed very high levels of Cu and Zn before the critical deterioration of the disease. In AD, the levels of Cu and Zn in CSF were significantly higher in patients with late-onset AD (p<0.01). In PD, we found significantly increased levels of especially Cu and Zn in particular (p<0.01) and Mn (p<0.05) in CSF. A multiple comparison test suggested that the increased level of Mg in ALS and that of Mn in PD were the pathognomonic features. These findings suggest that Cu and Zn in particular play important roles in the onset and/or progression of ALS, AD, and PD. Therefore, Cu-chelating agents and modulators of Cu and Zn such as metallothionein (MT) can be new candidates for the treatment of ALS, AD, and PD.     

Cerebrospinal fluid endothelin-1 in Alzheimer's disease and senile dementia of Alzheimer type.

We have measured the endothelin-1 concentrations in the cerebrospinal fluid samples from 5 patients with Alzheimer's disease (AD), 6 patients with senile dementia of Alzheimer type (SDAT) and 7 patients with other diseases without dementia (disease control: DC). The cerebrospinal fluid endothelin-1 level was significantly lower in AD than in DC. No correlation was observed between cerebrospinal fluid endothelin-1 concentration and any other factors such as age, duration from onset, systolic blood pressure, cerebrospinal fluid protein level or plasma endothelin-1 concentration in AD or SDAT. These results suggest a possible alteration of the endothelin-1 system in the central nervous system in Alzheimer's disease.     

等电聚焦电泳联合免疫印迹法检测寡克隆区带诊断神经系统炎性脱髓鞘疾病

目的 探讨等电聚焦电泳(IEF)联合免疫印迹法检测寡克隆区带(OB)在神经系统炎性脱髓鞘疾病(IDD)中的应用.方法 IEF联合免疫印迹法检测112例IDD及24例神经系统非炎性疾病(NIND)患者血清和脑脊液中OB,并进行对比分析.结果 与视神经脊髓炎(5/21,23.8%,x2=32.679)、急性播散性脑脊髓炎(1/4,Fisher精确检验)、系统性自身免疫病继发中枢神经系统IDD(3/19,15.8%,x2=37.425)、周围神经系统IDD(0,x2=51.944)和NIND(0,x2=51.944)患者比较,多发性硬化(MS)患者脑脊液OB阳性率(44/46,91.7%)显著升高(P＜0.01).IEF联合免疫印迹法检测OB诊断MS的敏感度为91.7%,特异度为89.8%,高于其他检测方法.2例急性播散性脑脊髓炎患者和1例MS患者血清和脑脊液OB有相同条带,呈"镜像分布".结论 IEF联合免疫印迹法检测OB在MS诊断中具有一定的临床价值.

Abstract：

Objective To explore the diagnostic value of oligoclonal band (OB) detected by isoelectric focusing (IEF) with immunoblotting in inflammatory demyelinating diseases (IDD) in nervous system.Methods Serum and cerebrospinal fluid (CSF) OB was detected by IEF with immunoblotting in 112 patients with IDD ( multiple sclerosis ( MS):n = 48;neuromyelitis optica ( NMO):n = 21:acute disseminated encephalomyelitis ( ADEM):n = 4;secondary IDD from systemic autoimmune diseases:n = 19;peripheral nervous system IDD:n =20) and 24 patients with non-inflammatory neurological disease (NIND).Results CSF-restricted OB was detected in 91.7% (44/48) of MS patients,23.8% (5/21) of NMO patients(x2nmO vs MS= 32.679),1/4 of ADEM patients (Fisher' s excact test),15.8% (3/19) of secondary IDD patients (x2secondary IDD vs MS = 37.425 ),0 of peripheral nervous system IDD patients (x2peripheral nervous system IDD vs MS =37.425) and 0 of NIND patients (x2NIND vs MS =37.425).MS patients had significantly higher percentage of patients with CSF-restricted OB ( all P ＜0.01),compared with NIND and other IDD patients.The sensitivity and specificity of OB detected by IEF with immunoblotting for MS were 91.7% and 89.8%,which were higher than that of OB detected by other methods.Identical serum and CSF OB ( "mirror pattern" ) was detected in 2 of 4 ADEM patients and 1 of 48 MS patients.Conclusion IEF with immunoblotting to detect OB is a reliable method of diagnosis for MS.     

Review: Tau in biofluids – relation to pathology,imaging and clinical features

Tau is a microtubule‐binding protein that is important for the stability of neuronal axons. It is normally expressed within neurons and is also secreted into the brain interstitial fluid that communicates freely with cerebrospinal fluid (CSF) and, in a more restricted manner, blood via the glymphatic clearance system of the brain. In Alzheimer's disease (AD), neuroaxonal degeneration results in increased release of tau from neurons. Furthermore, tau is truncated and phosphorylated, which leads to aggregation of tau in neurofibrillary tangles of the proximal axoplasm. Neuroaxonal degeneration and tangle formation are reflected by increased concentrations of total tau (T‐tau, measured using assays that detect most forms of tau) and phospho‐tau (P‐tau, measured using assays with antibodies specific to phosphorylated forms of tau). In AD CSF, both T‐tau and P‐tau concentrations are increased. In stroke and other CNS disorders with neuroaxonal injury but without tangles, T‐tau is selectively increased, whereas P‐tau concentration often stays normal. In tauopathies (diseases with both neurodegeneration and neurofibrillary tangles) other than AD, CSF T‐tau and P‐tau concentrations are typically unaltered, which is a puzzling result that warrants further investigation. In the current review, I discuss the association of T‐tau and P‐tau concentrations in body fluids with neuropathological changes, imaging findings and clinical features in AD and other CNS diseases.     

Cerebrospinal fluid markers in dementia with lewy bodies compared with Alzheimer disease

BACKGROUND: Most patients with dementia with Lewy bodies (DLB) exhibit diffuse plaque-only pathology with rare neocortical neurofibrillary tangles (NFTs), as opposed to the widespread cortical neurofibrillary-tau involvement in Alzheimer disease (AD). Another pathological difference is the astrocytic and microglial inflammatory responses, including release of interleukins (ILs), around the neuritic plaques and NFTs in AD brains that are absent or much lower in DLB. We analyzed cerebrospinal fluid (CSF) markers that reflect the pathological differences between AD and DLB. OBJECTIVE: To determine CSF concentrations of tau, beta-amyloid, IL-1beta, and IL-6 as potential diagnostic clues to distinguish between AD and DLB. METHODS: We measured total tau, beta-amyloid1-42, IL-1beta, and IL-6 levels in CSF samples of 33 patients with probable AD without parkinsonism, 25 patients with all the core features of DLB, and 46 age-matched controls. RESULTS: Patients with AD had significantly higher levels of tau protein than patients with DLB and controls (P<.001). The most efficient cutoff value provided 76% specificity to distinguish AD and DLB cases. Patients with AD and DLB had lower, but not significantly so, beta-amyloid levels than controls. The combination of tau and beta-amyloid levels provided the best sensitivity (84%) and specificity (79%) to differentiate AD vs controls but was worse than tau values alone in discriminating between AD and DLB. Beta-amyloid levels had the best correlation with disease progression in both AD and DLB (P =.01). There were no significant differences in IL-1beta levels among patients with AD, patients with DLB, and controls. Patients with AD and DLB showed slightly, but not significantly, higher IL-6 levels than controls. CONCLUSIONS: The tau levels in CSF may contribute to the clinical distinction between AD and DLB. Beta-amyloid CSF levels are similar in both dementia disorders and reflect disease progression better than tau levels. Interleukin CSF concentrations do not distinguish between AD and DLB.     

Activin A concentrations in human cerebrospinal fluid are age-dependent and elevated in meningitis

OBJECTIVE: Activin A, and its binding protein, follistatin (FS), are expressed in the central nervous system (CNS). We have previously shown elevated concentrations of FS in the cerebrospinal fluid (CSF) of patients with meningitis and increased concentrations of activin A in the CSF of rabbits with bacterial meningitis. METHODS: We measured CSF and serum concentrations of activin A and FS in normal subjects and in patients with various neurological diseases using previously validated immunoassays specific for activin A or FS. RESULTS: In healthy persons, serum concentrations of both activin A and FS were age-dependent. In CSF, concentrations of activin A ranged from 0.03 to 0.33 ng/ml and were strongly correlated with age in both sexes, whereas FS CSF concentrations were below the assay detection limit in most of the patients. Activin A concentrations in CSF of patients with various neurological diseases, including meningitis, chronic inflammatory CNS diseases, neurodegenerative diseases, tumors in the CNS, cerebral ischemia, intracerebral/subarachnoid hemorrhages, subdural hemorrhages and epileptic seizures, were compared with age- and sex-matched control patients. The comparisons revealed significantly elevated concentrations of activin A in patients with meningitis (P=0.017). Serum concentrations of activin A or FS were not affected by any of the neurological diseases examined. CONCLUSIONS: Our results show for the first time that in normal subjects concentrations of activin A in CSF are correlated with age, and furthermore, that activin A CSF concentrations are elevated in patients with meningitis. The latter underlines a role for activin A in acute inflammatory processes within the CNS.     

中重度阿尔茨海默病与血管性痴呆患者脑脊液tau蛋白的预研究

背景：阿尔茨海默病（Alzheimer’s disease,AD）患病率高、医疗费用高、照料困难,已成为老龄化社会面临的严重社会、经济问题。迄今,AD的诊断尚无可靠的客观诊断指标。近年来,国内外对AD患者脑脊液生物学标志物的研究甚多,AD患者脑脊液T-tau、P-tau升高已是不争的事实。但是,这些标志物与痴呆严重程度以及随病程进展的关系还有待进一步深入研究。
　　目标：比较中重度阿尔茨海默病（Alzheimer’s dis-ease,AD）与血管性痴呆（vascular demenita,VD）患者脑脊液（cerebrospinal lfuid,CSF）总tau蛋白（total tau,T-tau）和第231位苏氨酸磷酸化tau蛋白（P-tau231）的基线浓度,随访6个月,观察它们在AD患者与对照组之间的差异以及随病程进展的变化。
　　方法：基线期中度AD患者11例（10≤ MMSE ≤20）,重度AD患者10例（MMSE ≤9）以及年龄匹配的重度VD患者7例,其中7例AD与6例VD完成了6个月的随访。用双抗体夹心ELISA检测脑脊液T-tau, P-tau231的浓度。
　　结果：基线期AD组与VD组患者CSF T-tau的浓度分别为470.08（263.58）pg/mL、208.76(42.24）pg/mL,差异有统计学意义（Z=-3.369,p <0.001）;CSF P-tau231的浓度分别为90.94(49.86）pg/mL、42.96（13.10） pg/mL,差异有统计学意义（Z=-3.237,p<0.001）。重度AD与重度VD相比,CSF T-tau（Z=-2.830,p =0.005）、CSF P-tau231（Z =-2.392,p=0.017）的浓度仍有统计学差异,重度AD患者 CSF T-tau、CSF P-tau231的浓度比重度VD患者高。中度AD患者CSF P-tau231（Z=-2.605, p=0.009）的浓度显著高于重度AD患者。6个月随访期间,两组患者脑脊液T-tau、P-tau231浓度的变化均无统计学意义。
　　结论：AD患者脑脊液T-tau、P-tau231与VD相比显著升高。中度AD患者CSF P-tau231显著高于重度AD患者。6个月随访期间两组患者脑脊液T-tau、P-tau231浓度的变化均无统计学意义。