Evaluation of Apo A IV and Haptoglobin as Potential CSF Markers in Patients with Guillain-Barre´ Syndrome: A Cross-Sectional Study.

BACKGROUND: Brain- and blood-derived protein analysis in the cerebro-spinal fluid (CSF) in various studies performed abroad found that some proteins and their isoforms were altered significantly in Guillain-Barre´ syndrome (GBS) patients in comparison to controls. However, data are lacking in India with respect to the blood- or brain-derived proteins in patients of GBS. OBJECTIVE: This study aimed to identify the role of apolipoprotein A IV (Apo A IV) and haptoglobin as potential protein markers in CSF of patients with GBS in our population. MATERIALS AND METHODS: The study comprised 28 participants where 12 confirmed cases of GBS and 16 control subjects admitted for non-infectious neurological disorders were recruited after obtaining approval from the Institutional Ethics Committee. CSF glucose, protein, and adenosine deaminase were analyzed using an autoanalyzer. The concentrations of Apo A IV and haptoglobin were estimated with enzyme-linked immuno-sorbent assay (ELISA) kits. RESULTS: The CSF protein concentrations of cases were higher as compared to controls. The concentrations of haptoglobin and Apo A IV were higher in the confirmed cases of GBS as compared to the control subjects, and this difference was found to be significant. The receiver operating characteristic curve analysis for haptoglobin revealed that the area under the curve (AUC) was 0.867 (95% CI: 0.732-1.001), with a sensitivity of 83.8% and a specificity of 63.3%. The AUC for Apo A IV was 0.883 (95% CI: 0.758-1.009), with a sensitivity of 91.7% and a specificity of 73.3%. CONCLUSIONS: Haptoglobin along with Apo A IV can emerge as a potential biochemical marker in CSF for the diagnosis of GBS.

Differential cerebro spinal fluid proteome investigation of Leber hereditary optic neuropathy (LHON) and multiple sclerosis.

Leber's hereditary optic neuropathy (LHON) is a genetic disease leading to the loss of central vision and optic nerve atrophy. The existence of occasional cases of LHON patients developing a Multiple Sclerosis (MS)-like illness and the hypothesis that mtDNA variants may be involved in MS suggest the possibility of some common molecular mechanisms linking the two diseases. We have pursued a comparative proteomics approach on cerebrospinal fluid (CSF) samples from LHON and MS patients, as well as healthy donors by employing 2-DE gel separations coupled to MALDI-TOF-MS and nLC-MS/MS investigations. 7 protein spots showed significant differential distribution among the three groups. Both CSF of LHON or MS patients are characterized by lower level of transthyretin dimer adduct while a specific up regulation of Apo A-IV was detected in LHON CSF.

Suppression of food intake by apolipoprotein A-IV is mediated through the central nervous system in rats.

The aim of this experiment was to investigate whether the anorectic effect of apolipoprotein A-IV (apo A-IV) after lipid feeding is mediated via the central nervous system. Infusion of 0.5 micrograms of apo A-IV into the third ventricle failed to suppress food intake. Higher doses (1 micrograms or higher) of apo A-IV infused into the third ventricle inhibited food intake in a dose-dependent manner. In contrast, when apo A-I was infused into the third ventricle it had no effect on food intake. To further test the hypothesis that apo A-IV is an important factor controlling food intake, we administered goat anti-rat apo A-IV serum into the third ventricle of rats that were allowed food and water and lib. In all rats tested, this treatment resulted in enhanced food intake. In contrast, infusion of goat anti-rat apo A-IV serum failed to elicit such a response. Lastly, we determined the apo A-IV concentration in plasma and cerebrospinal fluid before and during active lipid absorption. Apo A-IV concentration in cerebrospinal fluid was about 1/20 that of plasma. Both serum and cerebrospinal fluid apo A-IV increased markedly as a result of feeding of lipid. In conclusion, we propose that apo A-IV may act centrally to control food intake.

Proteomic identification of potential protein markers in cerebrospinal fluid of GBS patients.

Increased protein level in the cerebrospinal fluid (CSF) is a characteristic of patients with Guillain-Barré syndrome (GBS), an acute inflammatory autoimmune disorder in the peripheral nervous system (PNS). However, the molecular mechanisms underlying the disease remain poorly understood and so far no reliable disease-related markers are available. By comparing the CSF proteome of GBS patients with control subjects suffering from other neurological disorders, it may be possible to identify proteins that involve in the disease process and thus to study the pathogenesis of GBS. We used two-dimensional difference gel electrophoresis (2D DIGE) technique, in combination with matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS), to determine the abnormal CSF proteins in GBS patients. Our data showed that the levels of six proteins and their isoforms in CSF were significantly altered in GBS patients compared with controls. Haptoglobin, apolipoprotein A-IV and PRO2044 (unnamed protein) were considerably increased in the CSF of GBS patients, whereas transthyretin, apolipoprotein E and fibrinogen were considerably decreased. We concluded that these six proteins may be involved in the pathogenesis of GBS and call for further studying the role of these proteins in the pathogenesis of the disease.

Cerebrospinal fluid and plasma apolipoproteins in patients with multiple sclerosis.

Apolipoprotein (apo) E is synthesized by cells of the central and peripheral nervous systems, and its synthesis and secretion in the peripheral nervous systems, and its synthesis and secretion in the peripheral nervous system of animals are greatly stimulated following Wallerian degeneration. It has been suggested that apo E functions in the metabolism of myelin lipids, but its physiologic role in nervous tissue has not been elucidated. To determine if apo E might play a role in demyelinating neuropathy, the concentrations were examined of apos E and A-1 in the cerebrospinal fluid (CSF) and plasma of patients with multiple sclerosis during clinical remission, and in patients with no neurologic disease. Serum and CSF albumin concentrations were measured to account for the possible influences of serum apo E concentration and/or altered blood-brain barrier permeability on the CSF apo E pool. A CSF index for apo E and apo A-1 was calculated in the same manner presently used for calculation of immunoglobulin G (IgG) production in the nervous system of patients with multiple sclerosis (MS). The results showed that the concentrations of apo E, apo Al, and albumin in the CSF of the MS patients were not significantly altered. The concentration of apo E in the serum, however, was significantly (p less than 0.001) decreased by 44 percent in the MS patients. The difference was relatively specific for serum apo E because the serum apo Al and albumin concentrations were unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased prothrombin, apolipoprotein A-IV, and haptoglobin in the cerebrospinal fluid of patients with Huntington's disease.

Huntington's disease (HD) is a progressive neurodegenerative disease caused by an unstable CAG trinucleotide repeat expansion. The need for biomarkers of onset and progression in HD is imperative, since currently reliable outcome measures are lacking. We used two-dimensional electrophoresis and mass spectrometry to analyze the proteome profiles in cerebrospinal fluid (CSF) of 6 pairs of HD patients and controls. Prothrombin, apolipoprotein A-IV (Apo A-IV) and haptoglobin were elevated in CSF of the HD patients in comparison with the controls. We used western blot as a semi-quantified measurement for prothrombin and Apo A-IV, as well as enzyme linked immunosorbent assay (ELISA) for measurement of haptoglobin, in 9 HD patients and 9 controls. The albumin quotient (Qalb), a marker of blood-brain barrier (BBB) function, was not different between the HD patients and the controls. The ratios of CSF prothrombin/albumin (prothrombin/Alb) and Apo A-IV/albumin (Apo A-IV/Alb), and haptoglobin level were significantly elevated in HD. The ratio of CSF prothrombin/Alb significantly correlated with the disease severity assessed by Unified Huntington's Disease Rating Scale (UHDRS). The results implicate that increased CSF prothrombin, Apo A-IV, and haptoglobin may be involved in pathogenesis of HD and may serve as potential biomarkers for HD.

Comparative proteomics analysis of cerebrospinal fluid of patients with Guillain-Barré syndrome.

To better understand the pathophysiologic mechanisms underlying Guillain-Barré syndrome (GBS), Comparative proteomic analysis of cerebrospinal fluid (CSF) between patients with GBS (the experiment group) and control subjects suffering from other neurological disorders (the control group) was carried out using two-dimensional gel electrophoresis (2-DE) technique, in combination with matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) and database searching to determine abnormal CSF proteins in GBS patients. Image analysis of 2-DE gels silver stained revealed that 10 protein spots showed significant differential expression between the two groups of CSF samples. The expression of cystatin C, transthyretin, apolipoprotein E and heat shock protein 70 were decreased. However, haptoglobin, alpha-1-antitrypsin, apolipoprotein A-IV and neurofilaments were elevated. The subsequent ELISA measured the concentration of cystatin C and confirmed the result of the proteomic analysis. These identified proteins may be involved in the pathophysiological process of GBS and call for further studying the role of these proteins in the pathogenesis of the disease.

Proteomic analysis of the cerebrospinal fluid of patients with schizophrenia.

We applied proteomics technologies to analyze the cerebrospinal fluid of patients with schizophrenia. Such an analysis can result in the identification of proteins, which may play a role in the disease progress and thus lead to the discovery of clues of the etiology of schizophrenia. Cerebrospinal fluid from patients and controls was analyzed by two-dimensional gels and the proteins were identified by matrix-assisted laser desorption ionization mass spectrometry (MS) in the MS and MS/MS mode. 54 different gene products were identified, which were mainly plasma proteins. The level of apolipoprotein A-IV was significantly decreased in the schizophrenic patients compared to that in the controls. Little is known about the function of this apolipoprotein in the central nervous system. The levels of certain other proteins, like haptoglobin, fibrinogen, complement component 3, and Gc-globulin, were altered in the disease group as well, however, the changes did not reach a statistical significance.