Neuron-specific enolase and S-100 protein levels in cerebrospinal fluid of patients with various neurological diseases

Blood cell superoxide dismutase and enolase activities as markers of alcoholic and nonalcoholic liver diseases

Monitoring of chronic alcoholism would be facilitated by using sensitive biochemical markers in blood cells, mainly to detect differences between alcoholic subjects with or without liver injury. We propose two types of markers: the first one is superoxide dismutase (SOD) activity involved in the conversion of superoxide radicals (O2-.) formed during acetaldehyde oxidation by xanthine oxidase after chronic alcohol consumption; the second one is enolase activity with both isoenzyme forms: nonneuronal enolase (NNE) and neuron specific enolase (NSE) which has been shown to be modified in many injuries related to the glycolytic pathways. For SOD activity we found a significant increase in alcoholic patients with liver injury and mainly in cirrhotic patients with ascitis. Both enolase activities were also found to be significantly increased in alcoholic patients with liver injury but NNE activity was also increased in alcoholics without apparent liver disease. Our results suggest that increased activity of SOD and NSE in blood cells may be related to liver injury mainly in alcoholism while increased NNE activity may also be a marker of alcohol abuse without liver injury.

Cerebrospinal fluid neuron-specific enolase is decreased in multi-infarct dementia, but unchanged in Alzheimer's disease

Cerebrospinal fluid (CSF) levels of neuron-specific enolase (NSE) were measured in 22 patients with probable Alzheimer's disease and in 35 patients with multi-infarct dementia, and in 15 controls. CSF NSE in patients with Alzheimer's disease did not differ from those in controls. In patients with multi-infarct dementia without recent vascular events CSF NSE was lower than in controls or in Alzheimer patients. This finding is in accord with the prevailing opinion that vascular dementia is caused by multiple infarcts and not by continuous neuronal ischaemia.

Preparation and purification of gamma gamma enolase (neuron-specific enolase) using high performance anion exchange chromatography

A simple and rapid method, using only two chromatographic steps, is described for the purification and preparation of gamma gamma enolase isoenzymes from human and beef brain extracts. In the first step, a crude gamma gamma enolase was obtained by chromatography on Q-Sepharose Fast Flow column. The crude fraction was then purified by high performance anion exchange chromatography on a Mono-Q column. gamma gamma enolase obtained in this manner was shown to be homogeneous by two dimensional polyacrylamide gel electrophoresis and by high performance gel permeation chromatography. The yield of gamma gamma enolase by this method was 7-8 mg of pure enzyme per 100 g of brain.

High neuron-specific enolase level of cerebrospinal fluid in the early stage of Creutzfeldt-Jakob disease

The measurement of neuron-specific enolase level in serum and cerebrospinal fluid was conducted time-sequentially in an autopsy confirmed patient with Creutzfeld-Jakob disease. The level was markedly high in the early stage of the disease at which time the brain CT showed no or minimal abnormalities, while falling into the normal range in the advanced stage. This is the first report of the elevated level of neuron-specific enolase in Creutzfeldt-Jakob disease.

S-100 proteins

S-100 is a group of closely related, small, acidic Ca2+-binding proteins (S-100a0, S-100a and S-100b, which are alpha alpha, alpha beta, and beta beta in composition, respectively). S-100 is structurally related to calmodulin and other Ca2+-binding proteins. S-100 is abundant in the brain and is contained in well defined cell types of both neuroectodermal and non-neuroectodermal origin, as well as in their neoplastic counterparts. In the mammalian brain, S-100a and S-100b are confined to glial cells, while S-100a0 is neuronal in localization. Single S-100 isoforms bind Ca2+ with nearly the same affinity. K+ antagonizes the binding of Ca2+ to high affinity sites on S-100. S-100 binds Zn2+ with high affinity. S-100 is found in a soluble and a membrane-bound form and has the ability to interact with artificial and natural membranes. S-100 has no enzymatic activity. S-100 has been involved in several activities including memory processes, regulation of diffusion of monovalent cations across membranes, modulation of the physical state of membranes, regulation of the phosphorylation of several proteins, control of the assembly-disassembly of microtubules. Some of these effects are strictly Ca2+-dependent, while other are not. S-100 is being secreted or released to the extracellular space. In some cases, this event is hormonally regulated. Several S-100 binding proteins are being described.

Increased GFAp levels in CSF as a marker of organicity in patients with Alzheimer's disease and other types of irreversible chronic organic brain syndrome

Glial fibrillary acidic protein (GFAp), an astrocyte-specific protein, was determined in cerebrospinal fluid (CSF) of adults and children with global cognitive dysfunction. In children CSF-GFAp values were not closely associated with organic brain disease. However, GFAp values in CSF were increased in 65 of 121 samples of adults with dementia, independent of its cause. GFAp values were not correlated with the severity of the dementia. Increased levels in the CSF are believed to indicate reactive gliosis in most patients with dementia, whereas GFAp levels in encephalitic patients normalize after clinical recovery.

Determination in human cerebrospinal fluid of glial fibrillary acidic protein, S-100 and myelin basic protein as indices of non-specific or specific central nervous tissue pathology

The nervous system specific proteins glial fibrillary acidic protein (GFAp), S-100 and myelin basic protein (MBP) were determined in 535 human cerebrospinal fluid (CSF) samples. The level of all three proteins was increased in CSF of patients with nonselective destructive central nervous tissue disease such as encephalitis, cerebrovascular disease or tumoural compression. The increases in GFAp were more constant, making it a better marker of CNS pathology. Increases in MBP in CSF of patients with acute demyelinating disease were confirmed. S-100 did not seem to give more information as GFAp. Isolated increases of GFAp could be demonstrated in patients with dementia (Alzheimer type or multi-infarct dementia) or syringomyelia. Since CNS of these patients is very rich in fibrillary astrocytes, containing large amounts of GFAp, it is suggested that GFAp is to be considered as a specific marker of fibrillary gliosis in CSF and can be used as a diagnostic tool in dementia and syringomyelia.

S-100 protein and calmodulin levels in cerebrospinal fluid after subarachnoid hemorrhage

The levels of two calcium-binding proteins, S-100 protein and calmodulin, were measured serially in the cerebrospinal fluid (CSF) of patients after subarachnoid hemorrhage (SAH) and aneurysm surgery. These two proteins have a similar molecular structure and are highly concentrated in the central nervous system (CNS). The levels of S-100 protein found in the earliest postoperative CSF samples correlated with the preoperative SAH grades. High S-100 protein levels in the CSF were found in patients with poor SAH grades. Moreover, the prognosis of the patients correlated with the S-100 protein levels in the CSF samples taken during the immediate postoperative period and with the daily changes of the S-100 protein levels. Severe diffuse cerebral vasospasm was followed by a sharp S-100 protein increase. These results suggest that S-100 protein levels in the CSF provide a useful index of organic damage in the CNS, and furthermore that S-100 protein levels and their changes may have prognostic value for patients after SAH. On the other hand, there was a lack of correlation between the calmodulin levels and the preoperative grade or outcome. It would be inappropriate, however, to speculate from the results of this study that these calcium-binding proteins in the CSF play any causative role in pathological processes such as cerebral vasospasm or brain ischemia after SAH, since changes in the levels of these proteins followed the onset of clinical signs of deterioration.

Mammalian endoneurial fluid: collection and protein analysis from normal and crushed nerves

An elution procedure was developed for the extraction of endoneurial fluid from desheathed, rat sciatic nerves. The endoneurial fluid elutions (EFE) from normal and crushed nerves were evaluated for extracellular proteins by sodium dodecyl sulphate-pore gradient electrophoresis (SDS-PGE) after silver stain and after immune overlay following electrophoretic transfer to nitrocellulose using antisera to albumin (ALB), neuron specific enolase (NSE), and the major myelin glycoprotein (P0). After removal of the epineurium/perineurium, the EFE protein accounted for 3.6% (34-37 micrograms) of the total endoneurial protein which did not change with intra-arterial perfusion. The endoneurium was further fractionated to obtain an aqueous supernatant (S-I), an SDS-solubilized supernatant (S-II), and an SDS-insoluble fraction. SDS-PGE analysis revealed that the EFE has a distinctive protein composition relative to the other endoneurial fractions. A predominant band with Mr of 64,600; 4 major bands with Mr of 86,200, 61,000, 54,500 and 46,900; and several other minor bands were observed. The predominant band at 64,600 co-migrates with ALB and was demonstrated by immune overlay to be ALB, which was also the major protein in the S-I fraction. The uniqueness of the EFE was established by the absence of NSE, an enzyme marker for the cytoplasmic fraction of axons which was found to be present only in S-I (subunit Mr = 49,600), the absence of P0, and the distinctive protein profiles as determined by silver stain. Crush injury resulted in a progressive increase in the amount of protein found in the EFE as well as the S-I with a corresponding decrease in S-II protein as a function of time after crush (1, 2, 5, 10, 24, 48, 96, 168 h). Dramatic alterations in the protein profile were demonstrated in the EFE from crushed nerves after SDS-PGE indicating substantial changes in the endoneurium as a result of the axonal degeneration, demyelination, and breakdown of the blood-nerve barrier. Alterations in EFE proteins after crush were also observed by lectin overlay experiments after SDS-PGE. Analysis of EFE collected after crush for NSE and P0 were negative. It is concluded that the distinctive pattern of EFE proteins identified from normal nerve will permit their further characterization as a separate endoneurial protein compartment. Such an elution procedure for collection of endoneurial fluid can readily be adapted to human sural nerve biopsies from patients with peripheral neuropathy for characterization of the appearance of new proteins which may be used as markers of disease activity.

Preparation and characterization of monoclonal antibodies to human neuron-specific enolase

Neuron-specific enolase (NSE) has been increasingly recognized as a marker for neuroendocrine tumors including small cell carcinoma of the lung (SCCL). To prepare monoclonal antibodies (MAbs) specific for human NSE, we first developed a simple method of purifying NSE by direct chromatofocusing of a crude extract of human brain tissue. BALB/c mice were then immunized with our preparation of NSE, and MAbs against NSE were generated utilizing a hybridoma technique. The antibodies were screened against both NSE and non-neuronal enolase (NNE) by a solid-phase radioimmunoassay (SPRIA). After cloning and subcloning of hybridomas, two groups of anti-NSE MAbs were identified by SPRIA. One group reacted specifically with NSE but not with its isoenzyme NNE, irrespective of whether antigens were glutaraldehyde fixed or unfixed. A second group reacted with both NSE and NNE when the latter were glutaraldehyde fixed, but surprisingly with neither antigen in the absence of fixation. Group I antibodies were further characterized by immunoblotting, and by immunocytochemistry of normal brain and liver sections and sections of SCCL. The results further supported the specificity of group I antibodies for NSE. These MAbs have potential utility in the diagnosis and management of neuroendocrine tumors, and in further understanding the biology of NSE.

Serum muscle-specific enolase in progressive muscular dystrophy and other neuromuscular diseases

Serum muscle-specific enolase ( MSE , beta beta and alpha beta enolases) levels were determined in 162 patients with progressive muscular dystrophy (PMD) and other neuromuscular diseases by means of an enzyme immunoassay method. The relationships were examined between serum MSE , creatine kinase (CK) and other markers of muscle disease. Serum MSE was strikingly increased in Duchenne muscular dystrophy, and this elevation was more prominent in younger patients. Serum MSE was also increased in other types of PMD and certain other diseases. Serum MSE showed the highest correlation with CK. In the PMD group, the frequency of cases with elevated MSE was the same as in CK. These results indicated that serum MSE may well be a specific marker of muscle disease on a par with CK.